LETTERI NST I T U TE FOR A DVA NCED R ESE A RCHMarch 2021 Vol. 19

Special Interview

Investigating the origin of the Universe‒ Research about formation of structures in the Universe

from Big Bang to present ‒ Naoshi Sugiyama
Research Highlights

Restoration of Lost Music
Chihiro Inose

Cosmic Evolution of Galaxies and Baryons in the Universe
Daichi Kashino

Writing History in Late Antique Rome: A Study of Ammianus Marcellinus
Shunsuke Kosaka

Surviving in Seasonally Fluctuating Environments: How Animals Anticipate and Adapt
Tomoya Nakayama

Central Visual System of Fish-How Do Fish Look at the World?
Hanako Hagio

Archival Explorations of Extreme Solar Eruptions in the Past
Hisashi Hayakawa

Evolution of Bioluminescence in the Ocean
Manabu Bessho-Uehara

Non-holomorphic Modular Forms and Modular Knots
Toshiki Matsusaka-`XTWZM6M_8Pa[QK[_Q\P*MTTMϏ-`XMZQUMV\I\\PM1V\MV[Q\a.ZWV\QMZ
Qi-Dong Zhou

Toward Further Academic Advancementin the COVID-19 Era“If it be judged useful by those inquirers who desire an exact knowledge of the past as an aid to theinterpretation of the future, which in the course of human things resemble if it does not reflect it, I shallbe content.” So envisaged Thucydides the value of his great historiography written more than 2400
years ago. It is now certain that he was definitely right. In early 2020, his vivid description of thedisastrous situation of plague-ridden Athens in 431 BCE was suddenly translated into reality for all of
us who had never seriously dreamt of the ever-threatening menace of pandemic.
Concerning the activities of our institute, an ominous sign was the postponement of UBIAS
Directors' Meeting in March 2020 at Marseille. With the start of a new academic year in April (anacademic year in Japan starts in April and ends in March), other activities of our institute were also
suspended or obliged to be held online. One of the most important events of our institute, the Nagoya
University Lecture, which was scheduled to be held on November 14, was cancelled at the last minutebecause of the confirmed cases inside the university campus. We must admit that the coronavirus
pandemic is provoking serious problems in our daily and academic life, and now we fully realize the true
value of face-to-face communication and especially lively conversations over drinks after conferences.
But it must also be true that we should regard the current circumstance as a great and precious challenge
to change our traditional and conservative way of thinking.
The year 2020 marked the 10th anniversary of the UBIAS consortium, which has successfully
developed close collaboration of leading Institutes of Advanced Study (IAS) around the world. On thisoccasion, we, together with Nanjing IAS, proposed “Dialogue” as the Topic of the Year (ToY) for 2020.
Although confusions and difficulties caused by COVID-19 seem to continue well into 2021, it isbeyond doubt that dialogue remains essential to conducting interdisciplinary research and cutting-edge
scientific explorations. It is thus our great pleasure to confirm that the UBIAS steering committee
unanimously agreed to adopt “Dialogue” as ToY for 2021 as well. The importance of dialogue will
never be shaken even after the pandemic. On the contrary, dialogue will become more multifaceted as
we begin to experience it now online thanks to the development of information technolog y. We
sincerely hope that dialogue may further strengthen the partnerships among the UBIAS members andother institutes of leading research universities in order to promote more brilliant academic
advancement in the COVID-19 era.

Yoshiyuki SUTO
Director, Institute for Advanced Research

Director

SUTO, Yoshiyuki

19March 2021

LETTERI N S T I T U T E F O R A DVA N C E D R E S E A RC H

CON TEN TS
03

Special interview
Investigating the origin of the Universe ‒ Research about formation of
structures in the Universe from Big Bang to present ‒Naoshi SUGIYAMA

07

Research Highlights
Restoration of Lost Music
Chihiro INOSE
Cosmic Evolution of Galaxies and Baryons in the Universe
Daichi KASHINO
Writing History in Late Antique Rome: A Study of Ammianus Marcellinus
Shunsuke KOSAKA
Surviving in Seasonally Fluctuating Environments:
How Animals Anticipate and Adapt
Tomoya NAKAYAMA
Central Visual System of Fish-How Do Fish Look at the World?
Hanako HAGIO
Archival Explorations of Extreme Solar Eruptions in the Past
Hisashi HAYAKAWA
Evolution of Bioluminescence in the Ocean
Manabu BESSHO-UEHARA
Non-holomorphic Modular Forms and Modular Knots
Toshiki MATSUSAKA-`XTWZM6M_8Pa[QK[_Q\P*MTTMϏ-`XMZQUMV\I\\PM1V\MV[Q\a.ZWV\QMZ
Qi-Dong ZHOU

25

IAR People

33

IAR Information

Cover Picture :Deep sky image taken by the Hyper Suprime-Cam mounted on the Subaru
Telescope at the Mauna Kea mountain summit on the Island of Hawai’i.
(Photograph of Daichi Kashino, YLC Assistant Professor. See page 09.)

Special
Interview

NaoshiSugiyama
Dr. Sugiyama was born in 1961 in Germany.
He is a professor at the Graduate School of Science. He also has been provost of Nagoya University since 2019 and served as atrustee of the Tokai National Higher Education and Research System since 2020. As a cosmologist and a leader of the world
project with telescopes, Dr. Sugiyama is working to elucidate the dark matter and the universe's origin. He received his
doctorate (in science) from Hiroshima University in 1989. He designated an Assistant professor at the University of Tokyo in
1991, and an Associate Professor at the Graduate School of Science, Kyoto University in 1996, a professor at the National
Astronomical Observatory of Japan in 2000 before taking on his current positions in 2006. Since April 2020, Dr. Sugiyama has
been the Director of Nagoya University Institute for Advanced Study (NAIAS).

Investigating the origin of the Universe‒ Research about formation of structures in the Universe
from Big Bang to present ‒̶̶ Dr. Sugiyama, you are a cosmologist, a Trustee of theTokai National Higher Education and Research System,and the Provost in charge of Supervision and Research at
Nagoya University. In this interview, we would like to ask
you questions about your career as a researcher in the firsthalf and about university administration in the second half.
First of all, how did you first come to think of becoming a
research scientist?
SUGIYAMA: I was born in 1961 in Germany, where my father had
been a research fellow in the university, and I grew up in KunitachiCity, Tokyo, and Kawasaki City. As a child, I was a serious bookworm, the kind who would check out every single book from thelibrary. I also enjoyed playing the piano and the flute. While reading
scientific books, I came to think that physics, in which one studies

03 | IAR LETTER | March 2021

the principles of nature, would be an interesting way to try to understand this world. I had the audacity to write for my middle school’s
graduation essay collection “I will be a physicist and win the Nobel
Prize” (laughs).

̶̶ You first entered the Department of Physics in the
Faculty of Science and Engineering at Waseda University.
SUGIYAMA: Yes. In my senior year, I joined Prof. Mikio Namiki’s
research unit on elementary particles. He was a lofty scientist who
didn’t flock. He taught us not to imitate others or follow fads inresearch. I continued to graduate school. That was exactly the time
when physicists had begun talking about how dark matter formed
structures in the Universe. I became interested in understanding the
Universe, in particular, the formation of a variety of structures in theUniverse. This interest originated from my research about dark
matter particles from the perspective of elementary particle physics.
Unfortunately, there were no professors specializing in the subject at
Waseda, and in those days it was virtually impossible to transfer toanother university at the doctoral level. So I was at a loss what to do
for a while until I learned by chance that there was a vacancy for adoctorate student in cosmology at the Research Institute for Theoretical Physics of Hiroshima University. I was allowed to take theexam to transfer.

̶̶ Could you explain to us briefly the cosmology thatyou started in the doctoral course?
SUGIYAMA: It is a discipline that studies the origin and history of
the Universe as a whole. In this discipline you focus persistently on
the Universe as a whole, not on individual celestial objects such as
galaxies and stars. When I look back on my life as a researcher,encounter with people has played an enormously important role. At
Hiroshima University, I had the good fortune of meeting Profs.
Hidekazu Nariai and Kenji Tomita, who were doing highly original
research in cosmology. Moreover, almost at the same time as mytransfer to Hiroshima, a very talented young researcher named Misao
Sasaki arrived there. He and Kenji Tomita, both Associate Professors
at that time, gave me a research theme, which was to study the formation of structures in the Universe through fluctuations, that is, bumps
and wiggles of densities that were made during the early phase of the
Universe. It is understood that those fluctuations have developed
into galaxies and other structures, held together by gravity over a
period of 13.8 billion years. In the Universe, there are essentially dark
matter, light, and ordinary matter, which interact with each other toform structures. Dark matter is invisible, but it forms and supports
visible structures in the Universe, such as galaxies and galaxy clusters.
The visible parts of galaxies and galaxy clusters are composed of ordinary matter, that is, elements. Elements have been attracted to thegravity of dark matter and formed stars, galaxies, and galaxy clusters.
In the Universe, light also interacted with matter through scatteringand by gravity until approximately 380,000 years after the Big Bang.
My research involves theoretically predicting how this light has since
split to be observed today and what information can be drawn from
that. The light that we can observe today is called cosmic microwave
background (CMB) radiation.

̶̶ So we can say that your main research interest is thestudy of CMB.
SUGIYAMA: CMB is a microwave emission that is observed almost
isotropically from all directions in the sky. A microwave is a type ofshort-wavelength radio wave, that is, an electromagnetic wave, a formof light. As I have said, this light formed “bumps and wiggles”
together with elements and dark matter for about 380,000 years
following the birth of the Universe. Until this epoch, light stronglyinteracted with electrons and protons, which formed atoms. At thatpoint, light was separated from other components and has freely traveled in the Universe. This is to say, CMB has carried informationfrom the time of the Big Bang directly to us. In other word, we cansay CMB is the fossil of the Big Bang. The existence of this radiation
was confirmed in 1965. But the bumps and wiggles, which should bein the radiation since they come from the same origin as structures in
the Universe, were not found. When I was a graduate student, I
thought that they would be found one day for sure because, intheory, they absolutely exist. So I decided to do research to thoroughly predict what could be learned when they were discovered. For
example, the type of dark matter should change the pattern of bumps
and wiggles. I realized that, at the time when nobody believed that
there was dark energy in the Universe, by incorporating it into theory
it was possible to make predictions about structures and the age of
the Universe with no contradictions from observed results. I was
deeply moved at that time.

̶̶ And sure enough, fluctuations were really observed…
SUGIYAMA: I obtained my doctorate in 1989, and that was a time
when space observation began to progress really rapidly. The Hubble
Space Telescope was launched in 1990. In 1992, I was working as a
postdoc assistant in Prof. Katsuhiko Sato’s laboratory at the University of Tokyo, when NASA’s COBE (COsmic Background Explorer)found fluctuations in the cosmic microwave background for the firsttime. I was ecstatic when I realized that what I had predicted reallyexisted. We were very proud that our paper on constraints on cosmology, which we wrote using COBE’s results, was published before they
were published in the same scientific journal. We managed this featbecause we wrote up our paper in a few days after obtaining a
preprint of the results by fax, as it was done in those days, and sent
the paper in immediately. The principal COBE researchers received
the Nobel Prize for their achievements in the COBE project in 2006.
After this, I went to UC Berkeley to continue my research with
Prof. Joseph Silk and his graduate students and postdoc researchers
there, examining what can be systematically understood from thepattern of fluctuations in observation results. Since COBE’s results,
theoretical research has progressed remarkably, resulting in a succession of satellite project proposals. The United States launched the
WMAP (Wilkinson Microwave Anisotropy Probe) in 2001, and theEuropean Space Agency launched Planck in 2009. I will never forgetthe moment when the detailed spatial pattern of fluctuations released
by WMAP around 2003 perfectly matched our prediction. Exactcorrespondence between the data observed by the satellite and our
prediction with adjusted theoretical parameters was a major triumphfor us.

̶̶ What lessons did you take away from your years abroad?
SUGIYAMA: I made a huge progress in my research while I was
abroad because I had a lot of time to spend solely for research. This
experience drove home to me that for young researchers, time
secured exclusively for research is far more important than researchfunds, for example. In natural sciences, it’s usually the case that you
produce good research results when you are young. You wouldn’t beable to continue as a researcher, however, if you didn’t solidify the

March 2021 | IAR LETTER | 04

core of your research while still young. I also learned the importanceof the environment. UC Berkeley was a special place. You would beworking in the computer room, and the person seated behind hecould be a Nobel laureate. During a seminar, a discussion would
suddenly begin, and you could recognize the persons speaking up
from your college textbooks. I remember Prof. Silk having coffee atan outdoor café every afternoon, discussing research with postdocs
and visitors from all over the world. There were many researchers on
the campus, and the atmosphere there really encouraged us to interact with one another.
Changing your environment, which is not just limited to goingabroad, has a positive impact on researchers because something
different begins in a new environment.

̶̶ Upon returning to Japan, you worked as an Associate
Professor at Kyoto University and then a Professor at the
National Astronomical Observatory of Japan before arriving at Nagoya University in 2006. What are your current
research themes?
SUGIYAMA: At present, my research group is mainly involved inthree projects. One project is theoretical research as the main Japanese participant in an international project called SKA. This project
involves building radio interferometer telescopes that fill a site ofabout one square kilometer in Australia and South Africa to find out
how the first stars were made and how stars and galaxies are formedin the Universe.
The second project involves the Subaru Telescope in Hawaii. We
use a new ultra-wide-field camera to precisely measure the shapes ofgalaxies in order to examine, among other things, the distribution ofdark matter, which deforms the shapes of galaxies due to the lensing
effect. We also use data mining and other technologies.
The third project is also about the early universe. We are studying cosmic inflation, how the Big Bang occurred, and how various
events in the early universe have affected the results of present-day
observations.
At the moment, we’re using competitive funds to actively hire
many young people to work in the group. We are a unit of about 10
academic faculty members and postdoc researchers and some 20
students. It’s a large research unit for cosmology by international
standards.

̶̶ It seems that not only your research but laboratory
administration is going very well.
SUGIYAMA: I have been most strongly inspired by the Berkeley
style: only a few tenured professors but many postdocs who areamong the world’s best. It is best to get young researchers heavily
involved, getting them to do quality projects and write papers at theappropriate time. I also encourage postdocs, and designated faculties
of our group to work with graduate students. When one gets
students to work with, one can’t be unclear about anything because
students keep asking about everything. So one has to work harder,
which broadens and deepens one’s understanding. Naturally, thisfurther stimulates the students. This is the best way to foster bothstudents and postdocs, I believe.

05 | IAR LETTER | March 2021

̶̶ Now that you have touched on managing yourresearch group, we wonder why you have come to get
involved in university administration while you are quite
enthusiastic about your research.
SUGIYAMA: The turning point came in around 2008, when our
research unit at Nagoya University in the domain of elementary
particles and astrophysics applied for designation as a global COE(Center of Excellence) as part of a national project. I was the representative applicant for our unit, whose research theme was the exploration of fundamental principles of the Universe. I wrote up a
rock-solid Q&A script with all the questions that I anticipated thescreening jury would likely ask. As a result, our project was adopted.
That was for 5 years’ project whose annual budget was approximately
200 million yen. You see, I work in cosmology, which sounds like a
dream-like domain, but I’m also a very realistic person (laughs). For
this project, I also concretized my idea of leadership. I put a reliable
person at the head of each section and let them take the lead on a
day-to-day basis, but I make sure to meet with the leaders regularly sothat I can manage the overall affair while taking full responsibility.
Things went very well this way. Looking back now, I think it’s exactly
a method of shared governance.
Through this project, I got to know the executive division of
the University, which led me to serve as an Advisor to the President.
As I made various proposals about where Nagoya University could be
improved, how it needed a branding strateg y, and so on, I was
appointed representative of the national project called “Program for
Leading Graduate Schools,” which is aimed at training young leading
researchers regardless of whether they are humanities or scientificmajors. I also served as the Deputy Director of the Institute ofAdvanced Research of Nagoya University. At around that time, I
began to have less time for research, but on the other hand, I havecome to realize how important and meaningful university administration is by learning from seminars for candidate university administrators from all over Japan through the university design workshop
organized by National Graduate Institute for Policy Study. After
working as the Dean of the Graduate School of Science, I have been a
Trustee of Nagoya University and the Tokai National Higher Education and Research System since 2019.

̶̶ What are the goals that Nagoya University is currently
working towards?
SUGIYAMA: We want Nagoya University to be among the top 100
universities in the world in terms of research within the next 10 years.
To achieve this, it is absolutely necessary that Nagoya be always at theSpecial Interview | Naoshi SUGI YA M A

world’s highest level in particle physics, space sciences, organic chemistry, and automotive engineering, among other fields of research. We
also want to contribute to industry and manufacturing to enhancesocial innovation. In this area, we have Toyota and many other related companies working for car manufacturing. It is time, however forthis region to create next big industires after car manufacturing,which is one of missiongs of Nagoya University, I believe. I would
love to see research develop in ways that lead to innovation, particularly in engineering and agriculture.

̶̶ With regard to university administration, Nagoya andGifu Universities established the Tokai National Higher Education and Research System (THERS) as the first Japanesenational universities to integrate their operating corporations
into an umbrella system that runs multiple national universities.
SUGIYAMA: We have undertaken something that enables us to dowhat a single university could not do otherwise due to Japan’s declining birth rate. Nagoya University has the country’s ninth largest
student body, approximately 16,000 students. The THERS is thethird largest, with a little over 23,000 students. The integration has
brought us merits of scale in terms of budget and importance for thenational government. We are envisaging a strong alliance between the
two universities, including the integration of the administrative divisions, the schools of agricultural science, and more.
I want the two universities to reinforce each other’s strengths
and make up for each other’s weaknesses. For example, Gifu University has a research center focusing on glycan, or, sugar chains. Nagoya
University has many researchers working in the same field. They havejoined Gifu’s research center, and a new larger research center has
emerged. The Japanese government highly evaluates the proposal of
the new research center, the human glycome project, and has selected
it for the MEXT’s major research project called Road Map 2020.
Collaboration in the field of aerospace technology also began toshow positive results. A mechanism which allows one university tobenefit from the other’s educational contents and research achievements is coming into shape. We have established an organization
called Academic Central, and preparation is already under way forthe two universities to jointly organize undergraduate, especiallyliberal arts education.
It’s not clear yet where the THERS will eventually land. Personally, I think it would be ideal if a third university and a fourth university join us, stimulating all universities to fully demonstrate theirrespective characteristics and add value to the overall presence.

uate students to come only when strictly necessary. Eventually, webegan to obtain sufficient evidence to suppose that with correct measures infection would not spread in classrooms and laboratories. So
now we pursue education and research normally, with careful anti-infection measures.
At the same time, this crisis has brought us some positive changes. For example, online platforms have made communication among
university personnel closer and more frequent. Webinars haveallowed many members of the academic faculties and administrative
staff of Nagoya and Gifu Universities to discuss education, research,governance, international affairs, and many other topics and allowed
the President and students to engage in direct discussions. This issomething we were unable to do before. We still have problems tosolve, such as how to expand these communication channels internationally. But for the moment, we are hoping to respond flexibly while
taking maximum care to prevent infection and gathering everyone’s
wisdom to deal with education, research, and all else in theliving-with-coronavirus mode.

̶̶ Would you like to send a message to the students,
including those who are preparing for admission to Nagoya
University amid the pandemic?
SUGIYAMA: I am sure many of you are feeling quite lost, not being
able to go to college as you would like to, due to the COVID-19 pandemic. For first-year students, in particular, I sympathize with yourdisappointment at the beginning of your new student life, which hasseriously been upset. It was a good thing that we were able to organize
classes online from the very beginning, although I don’t think thatthe condition of online communication has always been completely
problem-free, with some instructors having to grope their way. Still, I
must say that, regardless of the public health situation, online classes
make up an essential component of the digital university concept that
we aspire to realize, and the current crisis has made us, on the side ofuniversity administration, become resolute in moving forward in that
direction. As for the student side, I would like to see you continue
tackling challenges, turning this crisis into a positive experience, withthe unyielding spirit of courageous learned persons we all would liketo be, persons with a solid base capable of bravely confronting all situations. The University will spare no effort in supporting you in thisprocess. Let’s overcome this corona crisis together!

̶̶ The COVID-19 pandemic has put universities in avery difficult and complex situation. What responses are
you making in this regard?
SUGIYAMA: When the infection began to spread in early March
2020, the executive division led by those in charge of educational
affairs made the decision to switch to online classes immediately
because the academic year begins in April in Japan. At present, online
materials are always made available, even for face-to-face courses, incase there are students who prefer to attend classes online. For aperiod, we stopped everything, including research, banning undergraduates from coming to the campus in principle and allowing grad-Interview with Dr. Sugiyama was done by Nagoya IAR faculties and C. Ashihara(Chunichi Shimbun Co., Ltd). This interview article was written by C. Ashihara andtranslated to English under the responsibility of Nagoya IAR.

March 2021 | IAR LETTER | 06

Research Highlights _ 01

Restoration of Lost Music

This is score for biwa from the 14 century possessed by Kunaicho (Imperial Household Agency). First, the method of tuning is described, and then the name of the music and thescore are described.

Chihiro INOSE
Designated Assistant Professor of Young Leaders Cultivation Program
Graduate School of Humanities / Institute for Advanced Research, Nagoya University
E-mail: inose.chihiro@e.mbox.nagoya-u.ac.jp

Fujiwara no Moronaga was a great musician of the late 12th century. He transcribed various songs using Biwa score, which had been passed down by word of
mouth in those days. I clarify the actual condition of transcription at that time and restore the lost music based on the scores written by Moronaga.

INTRODUCTION
My research theme is to find out how people in the past passed on their
voices. Music vanishes from the moment it is played. We can hear neither thevoices of the ancients nor the sounds they play. Goshirakawa-in, who devoted
himself to imayō (popular songs of the time), wrote the following famous
saying in “Ryojin Hisho Kuden shu” in the latter half of the 12th century:
The sad thing of the voice is, after I have collapsed, nothing of them remains.

07 | IAR LETTER | March 2021

He lamented that the sound and melody of imayō do not remain after
his death. However, it is also true that through various methods, such asmusical scores and oral instruction, some people tried to hand down theirintangible music to posterity.
I examine the movement in the latter half of the 12th century in thispaper, focusing particularly on Shōmyō (Buddhist chanting of Buddhist
hymns) and its musical scores.

Chihiro INOSE
1. About Fujiwara no Moronaga
Fujiwara no Moronaga was the greatest person who recorded suchintangible music. It is said that Moronaga tried to preserve various kinds ofmusic as music scores as follows:Moronaga, Grand minister of state, made imayō (popular songs) on thescore of biwa, and later learned all the great songs.
“Ryojin Hisho Kuden shu”
Moronaga is known to have written the Biwa score “Sango Youroku” (12Volumes) and the Koto-score “Jinchi Youroku” (12 Volumes). On the other
hand, recent research has revealed that there are various scores transcribed byMoronaga.

“Monjusan.” It is a poem to praise Manjushri. The famous poet BAI Juyi is anincarnation of Manjushri, and this “Monjusan” is thought to be a poem
praising BAI Juyi as well. Waka is a quotation from “Takigi San,” which
describes the Buddha's previous life. Scripture originated in India, Chinese
poetry in China, and Waka in Japan. Different languages are unified under
Buddhist music.
It can be seen that each of the main elements of the court culture had astatement to praise Buddhism as described above and that this Buddhist
music was transcribed by Moronaga. Moronaga included these songs in his
Biwa score either because of the characteristics of the melody or because these
Shōmyō scores were sung in many Buddhist rituals.

2. Moronaga’s scoring method
Moronaga scored according to the Biwa score. Biwa and Hakase scores
were the main musical scores recorded in this period. The Biwa scorecomprises musical score with lyrics written on the left-hand side or theright-hand side. Each character of the musical score constitutes a chord(arpeggio), and the highest note of this chord becomes a basic melody. On theother hand, a horizontal line is written on the left-hand side and theright-hand side of the lyrics in the Hakase score, and the melody comprises
the starting point and the angle of the horizontal line. It is characterized by its
ability to express subtle heights by using wavy lines and curves. The Biwa
score was largely created by nobles and the Hakase score by monks.

Left-hand side figure: Biwa score / Right-hand side figure: Hakase score

3. About “Shōmyō no Fu”
Moronaga also transcribed Waka and Fuzoku (a popular song in easternJapan at the time) using this method. Among them, musical scores for
Shōmyō are attracting attention. Shōmyō is a kind of Buddhist music and ischaracterized by its unique melodies. A score called “Shōmyō no Fu” isavailable in the Kunaichō.
There are three songs in this score: Buddhist scriptures, Kanshi (Chinese
poetry), and Waka poems. The scriptures are quoted from “Lotus Sutra,”which is the most widely known sutra in Japan. Kanshi is a quotation fromMarch 2021 | IAR LETTER | 08

Research Highlights _ 02

Cosmic Evolution of Galaxies and Baryons
in the Universe

Figure 1. Deep sky image taken by the Hyper Suprime-Cam mounted on the Subaru Telescope at the Mauna Kea mountain summit on the Island of Hawai’i.

Daichi KASHINO
Designated Assistant Professor of Young Leaders Cultivation Program
Graduate School of Science / Institute for Advanced Research, Nagoya University
E-mail: daichi@nagoya-u.jp

he present-day universe is a rich world containing various elements, which have assembled into stars, galaxies, and living organisms. How have these elements

T and their composite matters evolved through cosmic time? Heavy elements are produced by fusion reactions inside stars, and stars form inside galaxies.
Galaxies thus play key roles in the evolution of materials in the universe. Recently, I have become interested in understanding cosmic reionization, which is a major
event that matter re-ionized after the end of the cosmic dark ages. We are carrying out dedicated observations using the world’s largest telescopes, such as the Subaru
Telescope, ALMA, and the James Webb Space Telescope. Herein I describe our ongoing projects and present our first result.

INTRODUCTION
The earliest stars and galaxies are thought to have formed in the first
hundreds of millions of years after the birth of the universe. The period
before the first objects formed is called the dark ages. After this period, theintergalactic gas (mainly composed of neutral hydrogen) filling the universe
was gradually reionized by radiation from ancient astronomical objects. This
process, called cosmic reionization, was the last major phase transition of baryons (i.e., ordinary matter) in cosmic history, and is thought to have been
almost complete when the universe (currently 13.8 billion years old) reached
an age of one billion years. Over the last decades, the technologies for astronomical observations have remarkably progressed, and the history of the
09 | IAR LETTER | March 2021

universe is now largely understood. As one of the last remaining mysteries,
reionization is among the most exciting frontiers of modern astronomy andcosmology.
To elucidate the process(es) of reionization, we must understand theproperties of ionizing sources (stars, galaxies, and/or active galactic nuclei),the physical conditions of the intergalactic medium, and the interactions
between galaxies and the circumgalactic gas. Reionization occurs when theradiation from nascent galaxies contacts the surrounding gas. The absorption
features in the spectra of background distant quasars1 are useful for probing
the physical conditions of the foreground cosmic gas. Near the Epoch ofReionization, the remaining neutral hydrogen atoms absorb Lyα photons

Daichi KASHINO(121.6 nm) and give rise to deep Lyα troughs in the spectra of the quasars,
from which the opacity (or optical depth) of the universe can be measured.
Interestingly, accumulated measurements of the effective Lyα optical depth
have shown that spatial fluctuations in the opacity of the cosmic gas (i.e., thecolumn density of the residual neutral hydrogen) increase dramatically near
the Epoch of Reionization. The origin of these fluctuations, however, remains
highly uncertain. The observations have been explained by different theoretical models, which must be verified by further observations.

Figure 2. Image of the James Webb Space Telescope. Copyright: spacecraft
image NASA; background image ESA/Gaia/DPAC, CC BY-SA 3.0 IGO

galaxy survey with the Subaru Telescope, which is focused on exploring theorigin of the opacity fluctuations. In the following, I introduce this projectand present its first result.

CONSTR AINT OF REIONIZATION SCENARIOS BY
SUBARU/HSC GALAXY SURVEYS
Figure 1 shows a real image of our observing program using the Hyper
Suprime-Cam (HSC) mounted on the Subaru Telescope. Our program wasdesigned to test competing models of the origin of large spatial variations in
the Lyα optical depth of the intergalactic medium at the tail end of reionization. These models explain the observations by different “recipes”, and predict
different spatial correlations between the optical depth of the gas and theunderlying number density of galaxies. Therefore, the models can be distinguished in principle by surveying galaxies along the lines of sight toward background quasars with the Lyα opacity information.
In the first quasar field, we have already associated a significant
underdensity of galaxies to a region containing abundant amounts of residual neutral hydrogen (Kashino et al. 2020). Figure 3 shows the distributionof distant galaxies identified in our observations. This image is centered ona background quasar whose spectrum presents a remarkably large andopaque (i.e., high optical depth) absorption feature, where the galaxies areunder-dense (the paucity of galaxies manifests as a dark hole at the image
center). Our result is consistent with scenarios in which large opacity variations arise from enhanced fluctuations in the ultraviolet background radiation field or residual neutral islands, which remained until almost 2×108
years later than previously thought. Our program will observe six additional quasar fields, from which more conclusive statements will be drawn.

Furthermore, the absorption lines of metals (or heavy elements such as
C, O, Mg, and Fe2) ejected by galaxies appear in the spectra of backgroundquasars. The wavelengths of these absorption lines correspond to energy
transitions of the elements. Measurements of the incidence rates and strengthsof metal absorption lines have constrained the cosmic evolution of themetal-ion content in the universe. However, the gaseous processes occurringaround the earliest galaxies remain largely unknown, as only very few hostgalaxies associated with metal absorbers have been identified.
The launch of the next-generation space telescope, the James Webb
Space Telescope (JWST; Figure 2), will finally enable the spectroscopy ofgalaxies during the Epoch of Reionization. The exceptional high-sensitivity near-infrared spectrographs installed on JWST will obtain rest-frame
optical spectra of very distant galaxies. From these spectra, we will investigate the star formation activities in these galaxies and the physical conditions of their interstellar gas. The advent of JWST and other forthcoming
instruments is expected to revolutionize our understanding of reionizationin the next decade.

RESEARCH OBJECTIVES AND OUR PROJECTSWe are attempting to comprehensively understand the evolution ofgalaxies and the cosmic gas in and near the Epoch of Reionization. To thisend, we will combine the spectral data of distant quasars (which provide
information on the gaseous components) with deep observations of ancientgalaxies. In particular, we hope to elucidate 1) the origin of the spatial fluctuations in the optical depth of the intergalactic medium, 2) the evolution of
metals in the intergalactic gas and the interactions between galaxies and thesurrounding gas, and 3) the nature and evolution of nascent galaxies. Collectively, these studies will provide a global picture of reionization.
To achieve these goals, our team is planning a dedicated galaxy survey
with JWST in the sky regions towards known bright quasars with high-quality existing spectral data. The project will perform deep and wide slitless spectroscopy and imaging using the Near-InfraRed Camera (NIRCam), and will
provide a sample of approximately 500 galaxies in and near the Epoch ofReionization. From these data, we will investigate the relation between galaxies and the intergalactic gas. The data collection will begin in around Marchof 2022, roughly half a year after the launch (which is expected in October of2021).
The JWST data will be combined with our current and forthcoming
complementary observations in these and additional quasar fields, thereby
realizing a unique collaborative dataset. Specially, I am leading a ground-based

Figure 3. HSC sky image centered on the quasar J0148+0600. Shown are
the distribution of target galaxies at the tail end of reionization (circles) andthe surface density calculated from the number densities of those galaxies.
The surface density (from low [dark] to high [bright]) was smoothed by afixed aperture of 8 arcmin in radius.

Acknowledgements
The result presented here is based on data collected at the Subaru Telescope operated by
the National Astronomical Observatory of Japan.

References[1] Kashino D. et al., “Evidence for a Highly Opaque Large-scale Galaxy Void at theEnd of Reionization,” The Astrophysical Journal, 888, 6 (2020).
1
A quasar is an extremely luminous active galactic nucleus, in which a supermassive blackhole is surrounded by a gaseous accretion disk.
2
Astrophysicist refer all the chemical elements heavier than hydrogen and helium as
heavy elements or “metals” .

March 2021 | IAR LETTER | 10

Research Highlights _ 03

Writing History in Late Antique Rome:
A Study of Ammianus Marcellinus

Figure 1. Photograph of the author's bookshelf. The upper: Series of Japanese translations of Greek and Latin classics (Seiyo-koten-sosho). The lower: edited texts, commentaries,
translations, and, modern researches relating to Ammianus Marcellinus and the late antique city of Rome.

Shunsuke KOSAKA
Designated Assistant Professor of Young Leaders Cultivation Program
Graduate School of Humanities / Institute for Advanced Research, Nagoya University
E-mail: kosaka.shunsuke@b.mbox.nagoya-u.ac.jp

uring so-called Late Antiquity (c. 250–700 CE) in European history, a variety of historical narratives were produced. They are important sources of

D information about the past but, given their diverse forms and subjects, their characteristics remain poorly understood. The purpose of this study is toelucidate the characteristics of Ammianus Marcellinus’s historical narrative, the Res Gestae, by analyzing it within the political and social context of its
composition in late fourth-century Rome. Based on the time and place at which it was written, my research seeks to reveal what Ammianus’s contemporaries
would have felt when reading his Res Gestae. To achieve this objective, this study compares the words of Ammianus with the results of current research in late
antique studies, thus deciphering the meaning of his text and the historical significance of his work.

INTRODUCTION
Historiography is a useful source of information about the past, providing us not only with historical facts but also insight into belief and ideology.
In this regard, European Late Antiquity is very interesting because in thisperiod various kinds of historiography were produced from the interaction of
Greek and Roman traditions with new elements, most notably Christianity.

11 | IAR LETTER | March 2021

Since the 1970s, historians have revealed various aspects of late antiquesocieties. At first, they tended to use historiographical texts simply as depositories of information on historical events. Relatively little attention was given
to inherent problems in the late antique historiographies themselves. However, scholars gradually noticed that these texts were not simple intermediariesof the past, but specific products reflecting a given author’s attitudes andShunsuke KOSAKA
the political and social context. Recent scholarship has recognizedthat understanding the social background of each text leads to the expansionof our knowledge on Late Antiquity.
Nevertheless, because of its detailed and vivid descriptions of lateRoman society and politics, Ammianus’s work is regarded as one of the great
Latin classics. Edward Gibbon, the author of The History of the Decline andFall of the Roman Empire, a classical work of the eighteenth century, offeredhigh praise of Ammianus: “an accurate and faithful guide, who has composed
the history of his own times, without indulging the prejudices and passions,which usually affect the mind of a contemporary”[1]. Thereafter Ammianus
was counted among the most significant historiographers by historians inmodern times. The Roman Empire of Ammianus by J. Matthews [2] relies
largely on Ammianus for historical information and has become the standard
text on the later Roman Empire and its society.
Since the end of the last century, however, historians have given more
attention to rhetorical technique. Doubting the credibility of Ammianus’s
words as a historical source, one historian even asserted that “his Res Gestae
exhibit the creative and imaginative powers of a novelist” [3]. This opinion
inspired subsequent researchers to investigate the text of Ammianus not interms of historical accuracy but of literary method.
Although this approach has certainly achieved significant results, little
consideration seems to have been given to the fact that Ammianus lived in thecity of Rome. His texts must have reflected the political and social situation oflate antique Rome.

inscriptions and their appearance. I have already surveyed twenty buildings in
the city of Rome that are mentioned in the Res Gestae. Additional surveys areneeded for sites in the Vatican and the suburbs of Rome.
To elucidate the meaning of Ammianus’s narrative for his contemporaries in Rome, my study compares his texts with writings and inscriptions left bypeople mentioned in his work, and with the architecture and urban landscapeof the time. In the process, I examine what is included in Ammianus’s text andwhat is not. I determine whether it is intentional or unintentional throughclose reading of the narrative and rhetoric of the text itself. I then investigate
the significance of what Ammianus wrote or did not write relative to thehistorical facts (political and social context) that were prerequisite knowledge
among contemporary readers.

THE CITY OF ROME IN LATE ANTIQUITY
Recent research has significantly improved our knowledge of late
antique Rome. Over the last two decades researchers started to examine thecity in Late Antiquity, especially the fourth century. In the historical narrativeof the “decline of the Roman world,” the city of Rome had been considered asymbol of downfall. Research on the city had remained undeveloped apartfrom a few works on the Christianization of Rome. However, the emergenceof the concept of Late Antiquity in the 1970s encouraged new perspectives
on the old capital of the empire. Researchers revisited historical sources
including Ammianus. Combined with the rapid progress of archaeologicalresearch in Rome and the publication of a new edition of Latin and Greek
inscriptions from the city, this has brought a wealth of fascinating data to ourattention. We are now able to portray a lively, powerful image of society inlate antique Rome, and possess adequate data to compare with the text ofAmmianus.

RESEARCH FOCUS
In light of the research progress mentioned above, a new way to interpret
Ammianus’s historiography emerges. On reading his text, we sometimes findthat the author omits information we might expect him to narrate. It is
improbable that he had simply forgotten to mention it since, as recent
research has shown, Ammianus carefully constructed his narrative. Furthermore, because he and his contemporary readers had a shared knowledge ofRome’s history, they should have easily noticed intentional silences in the
narrative. Therefore, an examination of why Ammianus preferred silence may
help to unravel his hidden agenda.

SOURCES AND METHODSThe texts of Ammianus have been transmitted to us through manuscripts of the ninth century, which have been revised and published by classicists. The best known of these is Seyfarth’s edition [4], which the present
study largely relies upon. However, the accumulation of subsequent studies ofAmmianus has identified occasional errors. With that in mind, I have strived
to achieve a more accurate interpretation of the text.
For epigraphic texts, the emended and annotated collection of Latin
inscriptions is useful. However, for the most recent excavations and revisions,
it is necessary to review academic journals and research reports. Field surveys
of relevant sites have been carried out to confirm the original location ofReferences[1] E. Gibbon, The History of the Decline and Fall of the Roman Empire, 1776–1788,
chap. 26, part 4.
[2] J. Matthews, The Roman Empire of Ammianus, London: Duckworth, 1989 (reviseded., Ann Arbor: Michigan University Press 2007).
[3] T. D. Barnes, Ammianus Marcellinus and the Representation of Historical Reality,
Ithaca and London: Cornell University Press, 1998, p. 198.
[4] W. Seyfarth, Ammiani Marcellini rerum gestarum libri qui supersunt (in 2 vols.),
Leipzig: Teubner, 1978.

March 2021 | IAR LETTER | 12

Research Highlights _ 04

Surviving in Seasonally Fluctuating Environments:
How Animals Anticipate and Adapt

Japanese medaka (Oryzias latipes) with cherry blossoms, “sakura” in Japanese, one of the most famous symbols of spring in Japan.

Tomoya NAKAYAMA
Designated Assistant Professor of Young Leaders Cultivation Program
Graduate School of Bioagricultural Sciences / Institute for Advanced Research, Nagoya University
E-mail: tomoya@agr.nagoya-u.ac.jp

n most regions with a temperate climate, four seasons—spring, summer, autumn, and winter—cycle through the year. Since seasonal changes significantly
affect environmental conditions, animals living in these regions need to anticipate and adapt to these seasonal changes. It has been known animals change
their physiology and behavior between seasons to cope with environmental fluctuations. In addition, some seasonal activities are controlled by the endogenous
annual clock, which are known as circannual clock, in some animals. However, the molecular mechanisms underlying seasonal adaptive strategies remain unclear.
Japanese medaka (Oryzias latipes) (Top picture) is a good model to study seasonal adaptation because of its clear seasonality and suitability for molecular analysis.
Using this model, we recently demonstrated the molecular basis of seasonal changes in color perception and stress response behavior. We are now trying tounderstand the molecular mechanisms of circannual clock using this small fish.

I

INTRODUCTION
When you look out over the world, you will notice there are regionswith different climates. Although these regions have different environmental conditions, animals and plants have evolved and adapted to each condition. For example, the polar region or the desert environment is far too
harsh for most organisms due to their extreme temperature and food scarcity ; some organisms can still sur vive in these environments. On the
13 | IAR LETTER | March 2021

other hand, in a temperate climate zone, whose environmental conditions
are moderate compared to these harsh regions, dynamic fluctuations occur
during seasonal changes (Fig. 1). Since the environmental fluctuations
repeat every year, animals living in temperate regions need to predict andprepare for the next season. But how do organisms living in these regions
anticipate and adapt to impending environmental variations?

Tomoya NAKAYAMASURVIVAL STRATEGIES IN THE TEMPERATE ZONE
Animals undergo seasonal alterations in physiology and behavior tocope with the dynamic environmental changes. For example, there are seasonal changes in animal reproduction, growth, metabolism, immune function,and hibernation. Although the mechanism regulating seasonal reproduction
has been uncovered recently (1), the molecular mechanisms underlying otherseasonal activities remain unelucidated.

JAPANESE MEDAKA IS A GOOD MODEL TO STUDY SEASONAL ADAPTATION
Investigations using mice, Drosophila, and zebrafish have made significant contributions to life science research for many years. However, theseanimals lack seasonality because they originate in regional environments withlittle seasonal variation. Therefore, we have chosen a small fish, Japanese
medaka (Oryzias latipes), as a model for studying seasonal adaptation becauseof its highly sophisticated seasonal responses, availability of genomic information, and compatibility with the existing genome editing tools.

SEASONAL CHANGES IN COLOR PERCEPTION
Medaka alter their behavior between seasons. In winter, medaka are lessactive and stop breeding. However, from spring to summer, they become very
active and breed almost every day. Also, we found that medaka showedseasonal changes in light sensitivity. Because medakas’ body color becomesbrilliant in a show of nuptial coloration during the breeding season, we
hypothesized that the perception of nuptial coloration also varies between
seasons. We used virtual fish created with computer graphics to test medakas’
preference. Only summer medaka exhibited a preference for the virtual fishwith nuptial coloration, suggesting their color perception undergoes seasonalchanges. Although the changes in photosensitivity have been reported insome other species, their physiological and ecological significance had notbeen elucidated.
We utilized genome-wide expression analysis and genome editing techniques to study these molecular mechanisms and their functional significance.
By studying the change in the genome-wide gene expression in the eye of
medaka from winter to summer, we identified many genes involved in thephototransduction were induced in summer. Genome edited medaka lacking
the photopigment gene showed a reduced light sensitivity and a weakerpreference for virtual fish with nuptial coloration under summer conditions.
These results suggest that plasticity in color perception is crucial for the emergence of seasonally regulated behaviors (2).

LONG NON-CODING RNA, LDAIR, REGULATES STRESSRESPONSE BEHAVIOR
During the breeding season, animals need to increase their activity tofind their mating partners and produce offspring. Although these behavioral changes are advantageous to breeding, they simultaneously expose theanimal to environmental dangers, such as predation, interspecific competition, and intraspecific competition. As a result, many animals undergostress responses, such as self-protective and escape behavior, to decrease
these risks during the breeding season (3). However, the molecular basis ofseasonal chang es in stress response remains to be understood. By
genome-wide expression analysis of the brain, we found that uncharacterized long non-coding RNA (lncRNA), LDAIR, is strongly induced by thelong-day stimulus, which mimics the breeding season. We next performed
a genome-wide expression analysis of the genome edited, LDAIR knockout
fish to uncover the LDAIR’s function. We found that the LDAIR locus
regulates the corticotropin-releasing hormone receptor 2 (CRHR2), one of
the genes involved in stress response. The behavioral analysis of LDAIR
knockout fish revealed that LDAIR affected the fish’s self-protective behaviors under long-day conditions. Therefore, we propose that the photoperiodic regulation of CRHR2 by LDAIR modulates adaptive behaviors toseasonal environmental changes (4). Interestingly, while most of lncRNAs’
functions are still unknown, it has been reported that lncRNAs exist in
similar numbers to protein in mammals. Because lncRNAs are involved inseasonal adaptation in plants, we propose that lncRNAs may also regulate
environmental adaptation in animals.

INTERNAL CLOCK FOR ADAPTING TO THE ANNUAL
SEASONAL CYCLE
Organisms living on earth experience two fundamental periodicities,
daily and annual, generated according to the earth’s rotation and orbit.
Organisms have evolved internal biological clocks, i.e., the circadian clock andcircannual clock, to anticipate these cyclical changes. The circadian clock
generates a 24 -hour rhythmicity in many biological processes for adapting today-night cycles. The molecular mechanisms controlling the circadian rhythm
remained unknown until the early 1980s. Since then, three American scientists have discovered this mechanism and received the Nobel Prize in Physiology or Medicine for their work in 2017. The circannual clock drives annual
rhythmicity in several biological activities for the adaptation to seasonal
cycles. Pengelley and Fisher first demonstrated ground squirrels show endogenous annual rhythmicity in body weight, food consumption, and hibernationin the mid-twentieth century (5). Since then, many other organisms havebeen reported to show circannual rhythm in seasonal activities, such as reproduction, growth, and hibernation. However, the molecular mechanism of
circannual rhythms is still an enigma. In our previous study, we found thatmedaka exhibited annual rhythmicity in reproduction. A genome-expression
analysis of time-series samples from different seasons revealed several thousand transcripts that exhibited an annual oscillation. Currently, we are investigating how these genes generate annual rhythmicity.

Figure 1. Seasonal variations in day length, amount of solar radiation andwater temperature (Unpublished data).

Acknowledgements
I would like to express my sincere appreciation of Prof. Takashi Yoshimura for his
continual support for my research and comments on the manuscript.

References[1] Nakane and Yoshimura. Universality and diversity in the signal transduction
pathway that regulates seasonal reproduction in vertebrates. Frontiers in Neuroscience 8,115 (2014).
[2] Shimmura*, Nakayama*, et al. Dynamic plasticity in phototransduction regulatesseasonal changes in color perception. Nature Communications 8, 412 (2017). *Equal
contribution.
[3] Romero. Seasonal changes in plasma glucocorticoid concentrations in free-living
vertebrates. Gen. Comp. Endocrinol 128, 1–24 (2002).
[4] Nakayama*, Shimmura*, et al. Seasonal regulation of the lncRNA LDAIR modulates
self-protective behaviours during the breeding season. Nature Ecology & Evolution 3,
845–852 (2019). *Equal contribution.
[5] Pengelley and Fisher. Onset and cessation of hibernation under constanttemperature and light in the golden-mantled ground squirrel (Citellus lateralis). Nature
180, 1371–1372 (1957).

March 2021 | IAR LETTER | 14

Research Highlights _ 05

Central Visual System of Fish
‒ How do Fish Look at the World? ‒Figure 1. The brain of a transgenic zebrafish in which green fluorescent protein (GFP) is expressed in neurons of the visual relay nucleus (a nucleus of preglomerular complex[PG]) in the diencephalon. GFP-positive neurons extend axons to the telencephalon (especially to the lateral part of dorsal telencephalic area [Dl]). TeO, optic tectum. Orientation:r, rostral; c, caudal; d, dorsal; v, ventral. Scale bar = 500 μm. [From Bloch & Hagio et al., 2020, eLife]

Hanako HAGIO
Designated Assistant Professor of the Young Leaders Cultivation Program
Graduate School of Bioagricultural Sciences / Institute for Advanced Research, Nagoya University
E-mail: hagio.hanako@i.mbox.nagoya-u.ac.jp

wo ascending visual pathways to the telencephalon are present in most vertebrates. However, some species of fish possess only one visual pathway, although

T others have two. Our studies suggest that the common ancestor of actinopterygians possessed two pathways, and later, one of them was lost in the common
ancestor of acanthopterygians, which includes most species for fisheries. We also found that the visual pathway in goby fish has a topographic organization.
Furthermore, we investigated a gene specifically expressed in the diencephalic visual relay nucleus. In the future, we aim to elucidate functions of visual pathways
using genome editing and microscopic live imaging analyses on visually-evoked neural activities.

INTRODUCTION
Most vertebrates, including fish, recognize food and predators forsurvival as well as individuals of the opposite sex for reproduction using sensory systems. The visual sensory system is especially important for many vertebrate species. While it has been recognized that elucidation of vision in fish isextremely important in the academic field as well as the fisheries industry, the15 | IAR LETTER | March 2021

visual system of fish is poorly understood with only fragmental studies available. To understand vision of fish, revealing the visual pathways from theretina to the telencephalon is a necessary first step.
Mammals possess two ascending visual pathways from the retina to thetelencephalon (pallium/cerebral cortex). One of the two visual pathways inmammals is called the geniculate system in which retinal input is sent to theHanako HAGIO
primary visual cortex after relay in the lateral geniculate nucleus in the diencephalon. The other pathway is called the extrageniculate system, whereretinofugal information reaches the higher-order visual cortex via the superior
colliculus in the mesencephalon and then the lateral posterior nucleus-pulvinar complex in the diencephalon. Similarly, two visual pathways arepresent in birds, reptiles, amphibians, and cartilaginous fishes. Two visual
pathways also appear to be present in bichirs and sturgeons, which are non-teleosts and represent early branches of actinopterygian radiation. In teleosts,
the goldfish and carp possess two visual pathways to the telencephalon; however, the squirrelfish, which is an acanthopterygian fish, possesses only one
visual pathway or extrageniculate-like pathway.

EVOLUTION OF THE VISUAL PATHWAYS IN FISH
Knowledge on the visual pathways in fish is limited only to a handful of
species, despite the diversity of fishes, with more than 30,000 species. Therefore, we investigated visual pathways in the yellowfin goby, Acanthogobius
flavimanus, that appeared later than squirrelfish. We revealed that the yellowfin goby possesses only an extrageniculate-like pathway in which retinal inputs
reach the dorsal telencephalon via the optic tectum in the mesencephalon andthen the nucleus prethalamicus (PTh) in the diencephalon [1, 2]. Our studies
suggest that the common ancestor of actinopterygians possessed two pathways, and later, the geniculate-like pathway was lost in the common ancestorof acanthopterygians, which includes many species for fisheries (Figure 2). We
continue studies on the visual pathways in several fish species.

Figure 2. Evolution of the visual pathways from the retina to the telencephalon in fish (green circle: geniculate-like pathway; blue circle: extrageniculate-like pathway).

VISUAL RELAY NUCLEUS IN DIENCEPHALON OF FISH
We also found that the PTh of yellowfin goby or the visual relay nucleus
in the diencephalon is composed of two subnuclei (medial and lateral: PTh-m
and PTh-l, respectively) [3]. It is known that retinal projections to the optic

tectum are organized topographically; however, studies on the possible topographic projections of the tectum to the diencephalic visual relay nucleus
remained to be studied. We injected neural tracers into different tectal
regions. Our study revealed that the medial tectum projects to the PTh-m
and a ventromedial zone of PTh-l, and the lateral tectum projects only to adorsolateral zone of PTh-l. Therefore, the mediolateral axis of the tectum isdirectly projected upon the mediolateral axis of PTh-l, suggesting the topographical organization of tecto-prethalamic projections, as in mammals(Figure 3).

AIMING AT HIGHER VISUAL FUNCTIONS IN FISH
Larvae of the zebrafish are used as a model for fluorescence imaging
studies to visualize neuronal activities. Many neuroscientists observed
real-time neuronal activities in the optic tectum by visual stimulation using
fluorescent Ca 2+ indicator and DNA-encoded Ca 2+ indicators, such as
GCaMPs. Although visual information reaches the diencephalon mediated by
the optic tectum, much information is lacking regarding the neuronal activities in the diencephalic nucleus, since the knowledge on the diencephalicvisual center in zebrafish remains undetermined. Therefore, we have identified the visual relay nucleus in the diencephalon, which receives projections of
the optic tectum and sends axons to the telencephalon. We searched for transgenic zebrafish in which green fluorescent protein (GFP) is expressed inneurons of the visual relay nucleus and identified a gene specifically expressedin the nucleus (Figure 1) [4]. Thus, analyses on visually-evoked neuronal
activities may be possible in the diencephalic relay nucleus, a higher-ordervisual center than the optic tectum, using Ca2+ indicators.
It is necessary to investigate the telencephalic visual circuits and processing of visual information that reaches the telencephalon. We constructed anatlas of the telencephalon based on cytoarchitecture, neurochemical markers,
and gene expressions in Rhinogobius flumineus [5]. We are in the process ofobtaining data regarding intratelencephalic connections in some species ofteleosts, and in the future, we aim to elucidate functions using transgenic fish
and imaging analyses on visually-evoked neural activities.
We have collaborated with other neuroscientists to understand functional systems other than vision, such as the spinal cord and the cerebellum [6, 7].
We are collaborating with several researchers in Japan and Norway for theadvancement of research and education for aquaculture. In the future, wewould like to identify attractive visual stimuli for fishes and utilize their characteristics for the improvement of fishing gear and the like, to contribute not
only to the academic field but also to the fisheries industry.

Acknowledgements
I appreciate Dr. Naoyuki Yamamoto and Dr. Masahiko Hibi for their continued support,
and all the collaborators. Studies referred to in this article have been sported by Japan
Society for the Promotion of Science KAKENHI Grant Number 16J03625 and
20K15597 and by Nagoya University.

References

Figure 3. Topographic organization of the retino-tecto-prethalamic pathway(red: Information from the dorsal visual filed; blue: Information from theventral visual field) and a schematic illustration of the extrageniculate-likepathway in yellowfin goby from the retina to the telencephalon (bottom left).

[1] Hagio H et al., 2018. An ascending visual pathway to the dorsal telencephalon
through the optic tectum and nucleus prethalamicus in the yellowfin goby Acanthogobius…, J. Comp. Neurol., 526, 1733-1746.
[2] Miyazaki T, ... , Hagio H, et al., 2019. J. Morphol., 280, 526-533.
[3] Hagio H et al., 2021. Afferent and efferent connections of the nucleus prethalamicus in the yellowfin goby…, J. Comp. Neurol., 529, 87–110.
[4] Bloch S§, Hagio H§ et al., 2020. Non-thalamic origin of zebrafish sensory nuclei
implies convergent evolution of visual pathways in amniotes and teleosts, eLife, 9:
e54945, (§ co-first author).
[5] Kawaguchi M§, Hagio H§ et al., 2019. J. Comp. Neurol., 527, 874-900, (§ co-firstauthor).
[6] Yamamoto N, Nakayama T, Hagio H, 2017. Develop. Growth Differ., 59, 188-193.
[7] Nimura T, Itoh T, Hagio H, et al., 2019. Dev. Biol., 455, 393-408.

March 2021 | IAR LETTER | 16

Research Highlights _ 06

Archival Explorations of Extreme Solar
Eruptions in the Past

Figure 1. Reconstructed auroral visibility during the Carrington storm in 1859. The blue dots had been already known by the date of Hayakawa et al. (2019) and the red dots havebeen added in Hayakawa et al. (2020c).

Hisashi HAYAKAWA
Designated Assistant Professor of Young Leaders Cultivation Program
Institute for Space-Earth Environmental Research / Institute for Advanced Research, Nagoya University
E-mail: hisashi@nagoya-u.jp

isashi Hayakawa analyzes past solar eruptions and their terrestrial impacts using contemporary analog records. He analyzes sequences ranging from solar

H flares to geomagnetic storms in the analog records of past solar observations, geomagnetic measurements, and auroral sightings, quantitatively scaling theirintensities and reconstructing their time series. The existing databases of extreme solar flares and geomagnetic storms can then be chronologically extended for
centuries from less than one century to several centuries. By analyzing historical chronicles and diaries, Hayakawa and his colleagues hope to further extend ourexisting databases to millennial time scales for comparison with proxy data from natural archives. Based on historical observations of sunspots and solar coronae, he
intends to quantitatively improve and reconstruct long-term solar variabilities such as the Maunder Minimum and the Dalton Minimum. As such, they arecontextualizing modern solar storms and solar variability to longer time scales for comparisons with extreme cases.

INTRODUCTION
Although the Sun supports all terrestrial life, it occasionally erupts, flooding the near-Earth space environments with plasmas, radiations, and particles.
Solar flares from significant sunspots typically launch interplanetary coronalmass ejections (ICMEs). When sufficiently geo-effective, these ICMEs cause
geomagnetic storms in the terrestrial magnetic field and extend the auroral
oval equatorward. With its increasing dependence on technology-based infrastructures, modern civilization is becoming increasingly vulnerable to disruptive solar eruptions. In March 1989, the greatest geomagnetic storm in thespace age caused serious blackouts in Quebec, along with significant economic

17 | IAR LETTER | March 2021

impacts (Riley et al., 2018). The most intense geomagnetic storm ever recorded often is considered as the “Carrington storm” in September of 1859 (with amaximum -Dst of ~900 nT), which caused extreme geomagnetic disturbanceeven in India, and auroral observations down to the Caribbean coasts (Cliverand Dietrich, 2013). In modern analyses, the consequence of this event wasestimated as catastrophic and the aftermath was diminished only after years ofrecovery (Baker et al., 2008). Therefore, understanding these hazards is necessary for mitigating their potential economic and social impacts in future.
Fortunately or unfortunately, such superstorms are fairly rare. The Dst
index, which evaluates the intensity of mid-latitude geomagnetic disturbanc-Hisashi HAYAKAWA
es, has captured only one superstorm (the March 1989 event) during its
chronological coverage since 1957 (Riley et al., 2018). Bridging the gap
between the existing indices and the historical superstorm records (including
the September 1859 event) is of significant interest.

INVESTIGATIONS OF HISTORICAL ARCHIVES
To understand historical storms before the space age, we must consult
analog observational records of those events, which are sometimes publishedin yearbooks, journals, and other scientific publications. Additional records
are preserved in the archives of major observatories and libraries. Records in
non-scientific documents such as diaries and chronicles should also be
consulted, especially in qualitative narratives. Based on these records, we canreconstruct the time series of solar eruptions (solar flares) and terrestrial
impacts (geomagnetic storms and low-latitude aurorae). The equatorialboundary of the auroral oval is known to be empirically correlated with theintensity of a geomagnetic storm.

UNDERSTANDING THE CARRINGTON STORM
We first analyzed the terrestrial impacts of the Carrington storm, abenchmark of severe space-weather events. We know that aurorae triggered bythis event were observed at the Caribbean coasts, but the extant investigations
are geographically concentrated in North America and Western Europe.
Therefore, we extended our surveys to East Asia, Russia, Ireland, and Iberia in
the Northern Hemisphere (Hayakawa et al., 2019), and to South America
and Oceania in the Southern Hemisphere (Hayakawa et al., 2020c). Throughour investigations, the equatorial boundary of the auroral oval was updated to
an invariant latitude (ILAT) of ~|25.1|° (Hayakawa et al., 2020c).

weak solar cycle (SC14). After investigating four historical magnetograms, wereconstructed the maximum intensity of this event as -Dst ~ 531 nT (Figure2). This intensity was slightly below that of the most extreme geomagnetic
storm in the space age, but far exceeded the second-most extreme storm in thespace age. Moreover, this case report warns us that geomagnetic superstorms
can occur even near the minima of weak solar cycles (Hayakawa et al., 2020a).
We further analyzed the sequence of extreme solar flares and extreme geomagnetic storms in March 1946. We located evidence of an intense solar flare at
the Tashkent Observatory in Uzbekistan (see Figure 3). Based on four
mid-latitude magnetograms, we reconstructed the maximum intensity of theresultant geomagnetic storm as -Dst > 512 nT.

Figure 3: Time series of an intense solar flare recorded at Tashkent
Observatory (Hayakawa et al., 2020b), courtesy of Ulugh Beg AstronomicalInstitute (UBAI) of the Uzbekistan Academy of Sciences.

SUMMARY AND FUTURE WORKS
We have reconstructed the historical time series of intense solar eruptions and geomagnetic superstorms. However, several storms have not been
quantitatively examined. Applying the above analyses to these events would
chronologically extend the intensity estimates of historical storms. Moreover,
our analyses are potentially extendible to the period beyond the onset of theregular geomagnetic measurements began in the 1840s, using auroral records
as the primary references.

COMPARISON WITH OTHER SUPERSTORMSThe Carrington storm was not likely unique. We examined the auroral
records of the great storms in February 1872 and May 1921, and reconstructed their equatorial boundaries. The auroral ovals in the 1872 and 1921 eventswere found at |24.2|° and |27.1|° ILAT, respectively (Hayakawa et al., 2018,2019). These equatorial auroral extensions well agreed with that of the
Carrington storm (Hayakawa et al., 2019), and with reconstructions of thegeomagnetic measurements, in which the intensity of the May 1921 storm
was maximized at –Dst = 907 ± 132 nT (Love et al., 2019).

Acknowledgements
Hisashi Hayakawa thanks all his collaborators for fruitful discussions and valuable
contributions to the above analyses. He also thanks the Ulugh Beg AstronomicalInstitute (UBAI) of the Uzbekistan Academy of Sciences for kindly permitting use of the
Tashkent flare observations.

References

Figure 2: Reconstructions of the historical superstorm in October/Novemberof 1903 (Hayakawa et al., 2020a)

RECONSTRUCTIONS OF HISTORICAL SUPERSTORMS
The above reconstructions were extended to other historical superstorms. Thus far, we have identified at least seven superstorms post-1850,
occurring on September 1859, February 1872, October/November 1903,
September 1909, May 1921, March 1946, and March 1989. Especially, theOctober/November superstorm in 1903 occurred just after the minimum of a[1] Cliver, E. W., Dietrich, W. F., The 1859 space weather event revisited: limits ofextreme activity, Journal of Space Weather and Space Climate, 3, A31 (2013).
[2] Hayakawa, H., et al., The Great Space Weather Event during 1872 February Recorded in East Asia, The Astrophysical Journal, 862, 15 (2018).
[3] Hayakawa, H., et al., Temporal and Spatial Evolutions of a Large Sunspot Group andGreat Auroral Storms around the Carrington Event in 1859, Space Weather, 17,1553–1569 (2019).
[4] Hayakawa, H., et al., The Extreme Space Weather Event in 1903 October/November: An Outburst from the Quiet Sun, The Astrophysical Journal Letters, 897, L10(2020a).
[5] Hayakawa, H., et al., Intensity and time series of extreme solar-terrestrial storm in
March 1946, Monthly Notices of the Royal Astronomical Society, 497, 5507–5517(2020b).
[6] Hayakawa, H., et al., South American auroral reports during the Carrington storm,
Earth, Planets and Space, 72, 122 (2020c).
[7] Love, J. J., Hayakawa, H., Cliver, E. W., Intensity and impact of the New York
Railroad superstorm of May 1921, Space Weather, 17, 1281–1292 (2019).
[8] Riley, P., et al., Extreme Space Weather Events: From Cradle to Grave, Space Science
Reviews, 214, 21 (2018).

March 2021 | IAR LETTER | 18

Research Highlights _ 07

Evolution of Bioluminescence in the Ocean

Figure 1. Deep-sea coral Funiculina sp. collected at 1,000 m below sea level emits green light. Under natural conditions, blue bioluminescence is generated by coelenterazine andluciferase and is then converted to green by the green fluorescent protein.

Manabu BESSHO-UEHARA
Designated AssistantProfessor of Young Leaders Cultivation Program
Graduate School of Bioagricultural Sciences / Graduate School of Science / Institute for Advanced Research, Nagoya University
E-mail: bessho@bio.nagoya-u.ac.jp

ioluminescence is one of the most common characteristics of living organisms on the planet, especially considering that most animals that inhabit the ocean
are luminous. Although it is estimated that bioluminescence evolved independently more than 80 times across the tree of life, only a handful of luminous
animals have been chemically studied. Poor knowledge concerning its molecular mechanisms limits our understanding of the evolution of bioluminescence. To
understand bioluminescence evolution, I studied the biochemical mechanism of the light-producing reaction in unexplored animal groups, such as fishes, corals,
and many other deep-sea animals. In this article, I introduce my research by focusing on two recent works on the origin of bioluminescence in deep-sea corals andkleptoprotein bioluminescence in fish.

B

EARTH IS FULL OF BIOLUMINESCENCE
Bioluminescence is light produced by a biochemical reaction in aliving organism. On land, only a couple of animals are bioluminescent(e.g., fireflies and luminous mushrooms), but in the ocean, the majorityof animals from the surface down to the ocean floor can emit light.
Luminous organisms are found across a variety of taxa such as bacteria,
Ctenophora (comb jelly), Cnidaria ( jellyfish and coral), Arthropoda(shrimp and krill), and Vertebrata (tunicate and fish). A video camera
observation using a submarine found that 76% of macroscopic animals
are luminous [1]. This number represents the ecological significance of
bioluminescence in the ocean, indicating that natural selection prefers
bioluminescence evolution. In fact, a recent study reported that biolumi-

19 | IAR LETTER | March 2021

nescence evolved independently more than 80 times [2].
The bioluminescent reaction is the oxidation of the luciferin molecule catalyzed by luciferase protein with or without cofactors. The independent evolution of bioluminescence resulted in several unique luciferins and luciferases. Animals that have different evolutionary origins havedifferent luciferin and luciferase structures. A comparison of the chemistry of bioluminescence provides a clue to its evolution. However, thebiochemistry of bioluminescence has only been studied in a handful ofanimal groups. Here, I introduce my recent studies: a natural history of
luminous anthozoans; and a bioluminescent fish stealing luciferase fromits ostracod prey.

Manabu BESSHO-UEHARA
ANCIENT GLOW IN THE DEEP-SEA
Class Anthozoa, composed of hard and soft corals, sea anemones, andsea pens, is a large group containing approximately 7,500 species belonging to
the phylum Cnidaria. Luminous species are taxonomically sparsely reported
from 2 families in subclass Hexacorallia and 15 families in subclass Octocorallia. The distant relationship of several luminous groups in Anthozoa indicatedmultiple origins of bioluminescence. However, a poorly resolved Anthozoa
phylogeny limits our understanding of bioluminescence evolution.
Most of the previous studies on luminous anthozoans were descriptive,
lacked chemical analyses, and mainly focused on shallow-water species. The
sea pansy Renilla reniformes (Renillidae, Pennatulacea, Octocorallia) is the
only well-studied luminous anthozoan. Renilla emits blue light upon stimuli
using coelenterazine (luciferin), Renilla luciferase, and oxygen without cofactors. Coelenterazine is a common luciferin among marine luminous organisms, and Renilla luciferase is similar to bacterial hydrolase but is not comparable to any other known luciferases. Thus, revealing the origin of Renilla-type luciferase would lead to the elucidation of bioluminescence origin in
Anthozoa.
As a part of the Monterey Bay Aquarium Research Institute (MBARI)
project lead by senior scientist Dr. Steven Haddock, I explored the deep-sea
floor of Monterey Bay using a remotely operated vehicle (ROV). A superhigh-sensitivity camera mounted on the ROV enabled me to test the bioluminescence of deep-sea corals at 4,000m below sea level. During the expedition,
I discovered that one hexacoral sea anemone and three octocorals were luminous; these organisms are the first reported luminous specimens in theirrespective families. Chemical analysis showed that their molecular mechanisms were similar. Coelenterazine and coelenterazine-dependent luciferases
were detected in all of the anthozoans. Western blotting analysis using theanti-Renilla luciferase antibody suggested the homology of luciferase among
all the luminous octocorals tested. This result suggests that all the luminous
octocorals inherited light production abilities from a common ancestor in the
Silurian era [3]. Imagine the night ocean ~450 million years ago, there aremany ancient corals in front of you. A coral you touch suddenly emits green
light (Figure 1). Another coral displays a blue light wave propagating from thepoint you pinched. This might just be a dream, or reality in the ancient
deep-sea environment.
Out of 3,000 species in Octocorallia, why are only a few dozen octocorals known to be luminous? This study suggests that there are perhaps
hundreds or even thousands of octocorals that could be luminous species. Just
as trees in a forest that provide structural complexity to harbor biodiversity,
corals make up the base of the ecosystem that supports biodiversity in theocean. Although the ecological role of bioluminescence in corals is not understood, bioluminescence certainly has some function as a signal for communication with other animals. Human activities, such as deep-sea mining tocollect rare metals, have resulted in the resuspension of sediments over theyears, ruining bioluminescent communication and likely destroying ocean
biodiversity.

Figure 2. Luminous ostracods produce light using vargulin and luciferase.
Parapriacanthus ransonneti prey on ostracods and sequester both vargulin
and luciferase protein for light emission. (inset) Ventral view of P. ransonneti
bioluminescence.

KLEPTOPROTEIN BIOLUMINESCENCE
The golden sweeper Parapriacanthus ransonneti is a nocturnal coastal
fish that has two light organs (thoracic and anal) connected to the digestive
tract. A previous study showed that Parapriacanthus uses vargulin as luciferin,
but the luciferase protein and its encoding gene were unknown. To reveal theluciferase of Parapriacanthus, I purified the luciferase protein from the lightorgan using chromatography techniques based on luminescent activity. The
isolated fish luciferase was identical to the luciferase of the luminous ostracod
Cypridina noctiluca (Figure 2). The existence of Cypridina luciferase wasfurther confirmed by western blotting and observations with immunohistochemistry using the anti-Cypridina luciferase antibody. This finding was
unexpected because ingested proteins are generally digested and broken into
small peptide fragments and amino acid molecules, which retain no original
enzymatic activity. However, the luciferase protein in Cypridina retained thestructure and light-producing activity in the specific cells of the Parapriacanthus light organs, which are located after the stomach and digestive tract.
Stealing protein from prey is new to science and is also a novel process of
evolving a trait that already exists in another organism. This trait resembles
kleptoplasty, one example of which Sacoglossa sea slugs sequestering chloroplasts of algal prey for photosynthesis, and kleptocnidism, examples of which
nudibranchs, comb jellies, and flatworms sequestering stinging cells of cnidarian jellyfish or corals for defensive use. We named the protein sequesteringfound in the fish ‘kleptoprotein’ after those intriguing phenomena. Unlike
kleptoplastids and kleptocnidids, scientists have overlooked kleptoproteinsbecause exogenous proteins cannot be distinguished by microscopic observation. Recent advancements in mass spectrometry technology and multi-omics
research may lead the discovery of more kleptoproteins, allowing for further
elucidation of the complex connectivity of our lives in the Earth’s diverse
ecosystem.

LUMINOUS FISH
Fish are a diverse group and have evolved various ways to produce anduse light. Anglerfish and flashlight fish are popular fishes that rely on
symbiotic bacteria for their luminescence. On the other hand, other fishes
emit light without the aid of symbionts. Interestingly, some fishes use luciferin molecules, which is identical to other luminous creatures. For example, the ostracod Cypridina noctiluca, a sesame seed-sized crustacean, uses
vargulin as its luciferin. Vargulin has been detected in some luminous
fishes such as a sweeper Parapriacanthus, a cardinal fish Jaydia, and a midshipman fish Porichthys (three fishes belonging to different families!).
Scientists thought the fishes could obtain small luciferin molecules by
eating ostracods, similar to us obtaining vitamins from fruits, and could
produce light using its own luciferase. Although there are more than 800
species of luminous fishes that do not rely on symbionts for their luminescence, no luciferase has been identified, limiting our understanding of
bioluminescence evolution in fish.
In the course of identif ying the luciferase enzyme in fish in myresearch, I found a surprising phenomenon that has never been reported inany organism before [4].

Acknowledgements
I thank S. Okubo and T. Satonaka (Shima Maineland aquarium) and S. Abe (Yokohama
Hakkeijima Sea Paradise aquarium) for providing fish samples. I thank ROV pilots in
MBARI to collect deep-sea coral specimens.

References[1] Haddock SHD, Moline MA, Case JF., Bioluminescence in the sea. Annu. Rev. Mar.
Sci. 2, 443–493 (2010).
[2] Lau ES, Oakley TH., Multi-level convergence of complex traits and the evolution of
bioluminescence. Biol. Rev. (2020).
[3] Bessho-Uehara M, Francis WR, Haddock SHD. Biochemical characterization ofdiverse deep-sea anthozoan bioluminescence systems. Mar. Biol. 167, 1–9 (2020).
[4] Bessho-Uehara M, Yamamoto N, Shigenobu S, Mori H, Kuwata K, Oba Y.
Kleptoprotein bioluminescence: Parapriacanthus fish obtain luciferase from ostracod
prey. Sci. Adv. 6, eaax4942 (2020).

March 2021 | IAR LETTER | 20

Research Highlights _ 08

Non-Holomorphic Modular Forms andModular Knots

52（747 299 （in the homogeneous space SL ( ) ＼ SL ( ) . [4] Jos Leys.

Figure 1: The modular knot associated to a hyperbolic γ=

22

Toshiki MATSUSAKA
Designated Assistant Professor of the Young Leaders Cultivation Program
Graduate School of Mathematics / Institute for Advanced Research, Nagoya University
E-mail: matsusaka.toshiki@math.nagoya-u.ac.jp

odular forms are vital objects in classical and modern mathematics. This theory plays a crucial role as a bridge between number theory, topology,

M harmonic analysis, arithmetic geometry, combinatorics, representation theory, mathematical physics, etc. My research interest is investigating the rolesof its generalization called “non ‐ holomorphic modular forms” in this wide range of fields. In particular, I have been working on it from the viewpoints ofnumber theory and knot theory.

IN MATHEMATICS, the act of counting something has been a fundamental problem since ancient times. It has been solved using the theory of modular forms. We begin by giving an exciting connection between partitions andmodular forms to let the readers know the modular forms’ charm. A partition
function p(n) is a classical arithmetic function, which counts the number ofall partitions of a positive integer n. For example, the partitions of n = 3 and n= 4 are3 = 2 + 1 = 1 + 1 + 1,
4 = 3 + 1 = 2 + 2 = 2 + 1 + 1 = 1 + 1 + 1 + 1,

21 | IAR LETTER | March 2021

and so p(3) = 3 and p(4) = 5. We can easily obtain p(1) = 1, p(2) = 2, p(5) = 7,
and so on. Then, can we count the number p(n) for a given large number n?
For instance, what is p(200)? One hundred years ago, MacMahon computed
the value p(200) = 3,972,999,029,388. Of course, he did not count them one
by one, but he used a special function called a modular form. Let us now
consider the infinite product∞II 1 ‒1q = (1 + q + q + … ) (1 + q + q + … ) (1+ q + q + … ) …
n=1

n

2

2

4

3

6

Toshiki MATSUSAKA
and expand brackets as = 1 + q + 2q2 + 3q3 +5q4 +7q5 + …. We then observethat the coefficient of q4 corresponds to the number of partitions p(4) =5. All
partition functions are obtained by a relatively simple (one-line) sum-productformula
∞

∞

Σ

n=0

p n）qn =
（

II
n=1

1
=
1 ‒ qn∞3n2 + n
n
q 2
（‒ 1）

（Σ

n=‒ ∞

‒1

（

What is this infinite product? Let P(q) denote the product. In harmonic
analysis, the function P(q) is characterized by the Cauchy-Riemann differential equation and a certain symmetry, that is, P(q) is a (holomorphic) modular
form. In this example, the arithmetic question “Compute the value p(200)” issolved using the modular form P(q).

modular forms appear. The proof consists of two parts. The first part is the
topological relation between the linking number and the Rademacher
symbol. The second part is a closed explicit formula for the Rademacher
symbol shown by Dedekind in 1892. Further, Ghys put a simple question on
the linking number of two modular knots.
A DECADE LATER, Duke-Imamoglu-Tóth [1] suggested an answer to hisquestion. First, they constructed a suitable analog of the Rademacher symbol.
They showed that this Rademacher symbol gives the number of intersectionsof a modular knot and the Seifert surface for another modular knot using
Birkhoff ’s theorem. Here, a Seifert surface is a surface whose boundary is agiven knot. Therefore, we observe that this is the linking number of two modular knots, which answers Ghys’ question.

HARMONIC MAASS FORMS are “non-holomorphic” generalization ofclassical modular forms. The theory of harmonic Maass forms has been studied extensively since the discovery by Zwegers in 2002. The function is alsocharacterized by the same symmetry and another differential equation.
Though this new theory is generally more complicated than the classical one,it also has quite rich applications in number theory, topology, and mathematical physics. In my previous works [5, 6], I introduced a far broader generalization named “polyharmonic weak Maass forms,” and investigated them fromthe viewpoint of number theory.
IN THIS ARTICLE, we introduce my recent work [7] on a relation between
non-holomorphic modular forms and modular knots in topology. At the2006 International Congress of Mathematicians, Ghys [2] presented a talktitled “Knots and dynamics,” and asserted that “Isotopy classes of Lorenz
knots and modular knots coincide.” A knot is a loop made by connecting bothends of one piece of string in 3-dimensional space. Thus, a Lorenz knot is aperiodic orbit appearing in the Lorenz attractor.

Figure 3: An example of the Seifert surface for a knot (denoted by 7_4 in
the classification table of knots).

Does the above result allow us to count the linking number of two modular
knots? The answer is no. To do so, we need an arithmetic formula for theiranalog of the Rademacher symbol. In my work [7], we studied anothernon-holomorphic modular form named the “hyperbolic Eisenstein series” andgave a simple explicit formula for the Rademacher symbol. This result is acounterpart of Dedekind’s classical result. Recently, I obtained another generalization of Ghys’ result in collaboration with J. Ueki. Amazingly (or as we
imagined), a new type of non-holomorphic modular form has an importantrole there. In closing, I want to end with the conference’s title held at the
MPIM in 2017. “Modular forms are everywhere.”

Figure 2: The Lorenz attractor defined by the system of differential
equationsdx/dt = 10(y−x),dy/dt = 28x − y − xz,dz/dt = xy − (8/3)z,
and a Lorenz knot (white curve) [3].
a bOn the other hand, modular knots are defined for a matrix
with integer（c d （coefficients, ad − bc =1, and a + d > 2. To be precise, the modular knot isdefined in the homogeneous space SL2( )＼SL2( ), which is diffeomorphic to
the knot complement of a trefoil knot in S 3 . Figure 1 shows an example ofmodular knots (green curve) with the trefoil knot (yellow curve). These twoclasses of knots have entirely different origins. Ghys proposed that any Lorenzknot is realized as a modular knot. The figure shows that the green knot andyellow knot are tangled up. The green knot twines around the yellow knot
149 times. This winding number is called a linking number of two knots.
Thus, the counting problem occurs again. Is it possible to count the linking
number for a given modular knot? To solve this problem, Ghys establishedthat “the linking number equals the Rademacher symbol” defined for the
non-holomorphic modular form logΔ(τ). Thus, it is computable. Again,

Acknowledgements
I would like to express my gratitude to Jos Leys for providing a beautiful imagery ofmodular knots. I also thank Herbert Gangl for giving me a lovely metallic Seifert surface.
This work was supported by JSPS KAKENHI Grant Number JP20K14292.

References[1] W. Duke, Ö. Imamoglu, Á. Tóth, Modular cocycles and linking numbers, Duke
Math. J. 166 (2017), no. 6, 1179--1210.
[2] É. Ghys, Knots and dynamics, International Congress of Math., Vol. I, 247--277, Eur.
Math. Soc., Zürich, 2007.
[3] É. Ghys, J. Leys, Lorenz and modular flows: a visual introduction, A tangled talelinking lattices, knots, templates, and strange attractors, http://www.josleys.com/articles/ams_article/Lorenz3.htm.
[4] J. Leys, Mathematical Imagery, http://www.josleys.com.
[5] T. Matsusaka, Traces of CM values and cycle integrals of polyharmonic Maass forms,
Research in Number Theory 5:8 (2019), 1--25.
[6] T. Matsusaka, Polyharmonic weak Maass forms of higher depth for SL_2(Z), The
Ramanujan Journal, 51 (1) (2020), 19--42.
[7] T. Matsusaka, A hyperbolic analogue of the Rademacher symbol, arXiv:2003.12354.

March 2021 | IAR LETTER | 22

Research Highlights _ 09

Explore New Physics with Belle II Experimentat the Intensity Frontier

Event display of the particle detection in the Belle II experiment. The particles are generated by the collision of electrons and positrons.

Qi-Dong ZHOUDesignated Assistant Professor of Young Leaders Cultivation Program
Kobayashi-Maskawa Institute / Institute for Advanced Research, Nagoya University
E-mail: qzhou@hepl.phys.nagoya-u.ac.jp

ark matter, the dominance of matter in the universe, and many other phenomena still cannot be explained by the current framework of theories that

D comprise the Standard Model (SM) of particle physics. One useful approach to exploring new physics beyond the SM is to create an environment just likethe one that existed during the beginning of our universe using a colliding-beam accelerator and then precisely measure the decay reactions under these conditions.
Observing the quantum effect of new particles on the decay transformations of particles shows what we assume to be new physics. We have succeeded in collecting
data by operating the Belle II detector and superKEKB accelerator since April 2018. The detector upgrade and data analysis are being performed in parallel. In the
coming years, these data will help us understand the origins of matter and the universe.

INTRODUCTION
Quarks and leptons are the elementary particles that constitute thematter of our universe. Gauge bosons, such as photons, are defined asforce carriers, and the Higg s boson (the so -called “God particle”)
explains where the mass of these particles originates from. The proper23 | IAR LETTER | March 2021

ties and physical behavior of these elementary particles are describedthrough the theory called the Standard Model (SM) of particle physics.
Although the SM is believed to be theoretically self-consistent and has
demonstrated huge successes, it still leaves some phenomena unexplained, for example, dark matter and material dominance in theQi-Dong ZHOU
universe. To explore new physics beyond the SM, one useful approach is
to create an environment that imitates the environment that existed
when the universe began and then precisely measure the particle decay
under these conditions. If there are new particles involved beyond thosein the SM theory and they participate in the particle decays, their quantum effect could be measured as a small difference from the results that
the SM theory would predict. Belle II is an experiment dedicated to
exploring new physics beyond the SM in the flavor sector at the beam
intensity frontier by measuring the decay products from electron andpositron collisions in the SuperKEKB accelerator. The SuperKEKB
accelerator is located at KEK, Tsukuba, Japan. It is designed to achieve
the world’s highest instantaneous luminosity (6.5 × 10 35 cm −2 s −1 ) bycolliding electrons (7 GeV ) and positrons (4 GeV ). Belle II aims tocollect 50 ab −1 integrated luminosity (~60 billion B meson pairs) in an
operational span of 10 years. This massive amount of data allows theprecise measurement of rare heavy flavor decays, such as B meson decays.

(DAQ) system to handle the data flow with transmission speeds from 1 to
10 Gbps. Corresponding hardware and software developments have beennearly accomplished, the current system would be replaced by the beginning of 2021. The new system will be sufficiently capable of handling thedata flow for the rest of Belle II’ s operation time even if it achieves luminosity 40 times greater than the current record.

B ANOMALY
Lepton universality is an idea predicted by the SM. According to thistheory, all three types of charged lepton particles (electron, muon, and tau)should interact in the same manner with other particles. In the decays of
B→D (*)eν, B→D(*)μν, B→D(*)τν, all three types of decay transformations shouldbe created at an equal rate once differences in their mass are accounted for.
Moreover, the new particles appearing in the model beyond SM should besensitive to the heavy particles. In other words, the decay rate of B→D (*)τν
should be larger than B→D(*)eν and B→D(*)μν. Figure 1 shows the ratio of

Figure 2. Instantaneous luminosity of SuperKEKB measured from October
2019 to June 2020 [2].

DATA ANALYSIS
Belle II is still at the beginning of its operation. First, we are attempting
to analyze the data and to understand the detector. For example, we haveconducted a study to correct the momentum bias of the charged particles
reconstructed by the Belle II detector [3]. Momentum bias can directly affectthe detection of all particle decays involved in charged particles. When we
accumulate more data, the systematic uncertainties will become more criticalthan the statistical uncertainties. Simultaneously, we also established theanalysis framework to reconstruct the B→D(*)lν decays. The first measurementof the B→D (*) lν branching fraction using the Full Event Interpretation
algorithm based on 34.6 fb‒1 of Belle II data has been accomplished [4], andthe result is
Br(B→D(*)lν) = (4.51 ± 0.41stat ± 0.27syst ± 0.45)%
Here, 0.41 and 0.27 are the statistical and systematic uncertainties, respectively. This is lower than but in agreement with the current world average value.

REMARKS AND FUTURE PROPECTS

Figure 1. Ratio value of R(D) and R(D*) [1]. Marker is the prediction of SM,and each color region shows measurement results with uncertainties. The
red circle represents the average value of results from all the measurements.
The average measurement result is 3σ (standard deviation) away from the
SM prediction.

R(D(*)) = Br(B→D(*)τν) / Br(B→D(*)lν), l = e, μ, and Br((B→D(*)τν) denotes thebranch fraction of B→D(*)τν. The red circle represents the average value of
measurement results that slightly deviate from the theoretical prediction of
SM with an uncertainty of 3σ (standard deviation) but still below the 5σ,
which would be needed to claim that this difference indicates a discovery.
This evidence of deviation is called a “B anomaly” in the particle physics field.
To place this anomaly in context, it is necessary to collect much more data to
reduce the statistical fluctuation and improve the systematic uncertainties.

OPERATION AND UPGRADE OF THE BELLE II DAQSYSTEM
The Belle II experiment began collecting data in April 2018. It recorded 74.10 fb−1 data with data taking efficiency of 84.2% during the last run
period from March 2020 to June 2020. At 20:34 on June 15, 2020, theSuperKEKB accelerator achieved the world’ s highest instantaneous luminosity for a colliding-beam accelerator. As shown in Figure 2, the current
record of 2.40 × 1034 cm−2s−1 was obtained at 00:53 JST on June 21, 2020[2]. SuperKEKB is planning to increase the luminosity to approximately
40 times of the new record in the coming years. At the same time, Belle IIneeds to record the data without any leaking under these conditions.
Currently, there is an attempt to upgrade the Belle II data acquisition

The operation of the Belle II detector and superKEKB accelerator isproceeding smoothly. We believe that we can accumulate 1 ab−1 data that iscompatible with Belle’s full data by the end of 2021. Belle is Belle II’s predecessor. If 5 ab‒1 data can be accumulated by the end of 2023, that should be
sufficient to let us settle the “B anomaly.” At the same time, Belle II is exploring the new physics using many different decay channels in parallel [5]. There
will be more new results emerging in the forthcoming years.

Acknowledgements
This work was supported by Grants-in-Aid for Scientific Research, KAKENHI-JSPS
International Research Fellow Grants No. 18F18324.

References[1] Y.Amhis et al., (Heavy Flavor Averaging Group) Averages of b-hadron, c-hadron,and tau-lepton properties as of summer 2018, arXiv:1909,12524 (2019).
[ 2 ] S u p e r K E K B c o l l i d e r a c h i e v e s t h e w o r l d ’ s h i g h e s t l u m i n o s i t y,
https://www.kek.jp/en/newsroom/2020/06/26/1400/[3] Q. D. Zhou, Correction for tracking momentum bias based on invariant mass peakstudies, BELLE2-NOTE-PH-2020-030[4] Belle II Collaboration, Measurement of the semileptonic anti-B0→D＊+l-ν branching
fraction with fully reconstructed B meson decays and 34.6 fb -1 of Belle II data,
arXiv:2008.07198 (2020).
[5] Belle II Collaboration, Search for an Invisibly Decaying Z’ Boson at Belle II in e+e‒→μ+ ‒ ± ±μ (e μ ) Plus Missing Energy Final States, Phys. Rev. Lett. 124, 141801 (2020)

March 2021 | IAR LETTER | 24

IAR Core FacultyCommittee

The IAR Core Faculty Committee is composed of the Institute Director, Deputy
Directors, Full-Time Faculty Members, and member of the clerical staff, who promote
the Institute’s activities, and make proposals to the IAR Committee.

Affiliation : Director of Nagoya IAR / Professor of the Graduate School of Humanities
Research Field : Ancient Greek History

Yoshiyuki
SUTO
Director

Research Interests
My research interests include Aegean Archaeology, Ancient Greek History, and especially the study of contact
and interaction between Greek and Eg yptian culture in the Hellenistic period. As a member of Akoris
Archaeological Project I have been working in Middle Egypt for the purpose of elucidating the history of local
society under the Ptolemaic rule.

Affiliation : Deputy Director of Nagoya IAR / Professor of the Graduate School of Bioagricultural Sciences
Research Field : Molecular Plant Physiology, Phytohormone

Hitoshi
SAKAKIBARA
Deputy Director

Research Interests
My research interest is to understand how plants manage their growth and development under abiotic stressconditions, uch as nitrogen limitation. Plant orchestrates a number of cues including phytohormone actions
and metabolic responses to coordinate its development and metabolism at a whole-body level. I am studying
molecular basis of this topic with focusing on nitrogen-dependent regulation of phytohormone biosynthesis
and signaling.

IAR PEOPLE | IAR Core Faculty Committee 2020

Affiliation : Deputy Director of Nagoya IAR / Professor of the Graduate School of Science
Research Field : condensed matter physics (experiment)

IchiroTERASAKI
Deputy Director

Research Interests
Ichiro Terasaki synthesizes new materials, investigates their transport and magnetic properties, and develops
functions hidden there. His major research activity has been devoted to the thermoelectric properties oftransition-metal oxides including the layered cobalt oxides, and recently extended to giant nonlinear
conduction in strongly correlated systems such as conducting organic salts and layered ruthenates. His recent
interest extends to exotic magnetic materials such as room-temperature ferromagnetic semiconductors andspin-liquid candidates.

Affiliation : Deputy Director of Nagoya IAR / Professor of the Centre for Asian Legal Exchange
Research Field : Political Sociology, Politics
Research Interests

HirokoTAKEDA
Deputy Director

My research can be mapped out in an intersection of the following three major elements; political sociology,
gender and Japan / UK. Political Sociology is my disciplinary background. In particular, I developed a keeninterest in the studies on governmentality. As for gender, I have long been interested in gender issues and thecore of academic questions that I have continuously explored in my extant work--the ways in which the world of
the everyday life is linked with the state system --was formulated as an outcome of my effort to examine genderissues with reference to governmentality. Finally, Japan has been my primary source of case studies and recently,
I also started to explore the British cases.

Affiliation : Associate Professor at Nagoya IAR
Research Field : Egyptian Archaeology, Pyramid, 3D Survey
Research Interests

Yukinori
KAWAE
Full-Time Faculty

My research interests lie in the field of Egyptian archaeology, particularly in 3D surveys of ancient megalithic
structures and excavations of ancient settlements. My academic career started the excavation of the Lost City of
the Pyramids at Giza. Soon after the introduction of 3D technolog y in Eg yptian archaeolog y, I began
conducting an interdisciplinary research project to complete 3D surveys of pyramids. Recently, I expanded thecollaborative research to include a television production company as Open Innovation Project. My use of 3D
data challenges the unprecedented empirical analysis approach to understanding the mystery of the pyramids’
construction.

Affiliation : Associate Professor at Nagoya IAR
Research Field : Plant Physiology, Plant nutrients

SatomiKANNO
Full-Time Faculty

25 | IAR LETTER | March 2021

Research Interests
My research interest is understanding plant growth adaptation mechanisms according to environmental
nutrients conditions. Plant senses internal and external ion level and controls the ion transport system tooptimize their growth. I am working on these mechanisms focusing on phosphate, one of the macronutrientsfor plant growth, by using molecular biology technics and imaging technologies to trace ions in the living
plants.

Affiliation : Designated Lecturer at Nagoya IAR
Research Field : Observational Cosmology, Astronomy

Atsushi
J. NISHIZAWA
Full-Time Faculty

IAR
Steering Committee

Research Interests
My research interest ranges from theoretical aspects of cosmological model that explains accelerating expansionof the Universe, to the theory of galaxy formation. To reveal such problems in the Universe, large astronomical
data obtained by telescope is used. Recently I am working on the photometric redshift that determines the
distance to galaxies. The redshift of galaxies are of particular importance for doing both cosmology andastronomy. I am also interested in the methods of data analysis including machine learning.

The I A R Steering Committee plan, discuss, and decide on the Institute’s
academic activities.

Affiliation : Vise President of Nagoya University / Director of NAIAS / Professor of the Graduate School of Science
Research Field : Cosmology, Astrophysics, Structure Formation in the Universe
Research Interests

NaoshiSUGIYAMA

Affiliation : Professor of the Graduate School of Mathematics
Research Field : Partial differential equations

Mitsuru
SUGIMOTO
Steering Committee

Research Interests
Various phenomena of nature can be treated mathematically by describing them in the language of partial
differential equations (PDE). Through the analysis, I aim to extract new principles which comprehend concrete
phenomena. As a methodology of PDE, many properties of the solutions to PDE can be deduced from theircharacteristics, and I employ this idea to investigate quantitative properties of solutions like size, regularity, and soon. Simultaneously I proceed with the study of Fourier analysis as an important tool for such analysis.

Affiliation : Professor of the Graduate School of Medicine
Research Field : Biochemistry, Glycobiology

Tetsuya
OKAJIMA
Steering Committee

Research Interests
My research has focused on biochemical and biological analyses of O-glycan modification on glycoproteins.
Previous studies revealed that unique glycans such as O-fucose and O-GlcNAc regulate Notch signaling andNotch-dependent biological processes. Currently, I am investigating how O-glycan modification is coordinated tofine-tune Notch signal strength essential for developmental control and homeostasis. Given that Notch signaling
pathway is associated with many human diseases, elucidation of molecular mechanisms how O-glycans control
Notch activity will be of great pharmaceutical interest.

Affiliation : Professor of the Graduate School of Engineering / Director of Center for the Studies of Higher Education
Research Field : Photoresponsive polymer thin films

Takahiro
SEKI
Steering Committee

Research Interests
Photoresponsive organic and polymeric materials are attracting much attention due to great potential in
next-generation photonics technologies. My major research interest is to study photoresponsive (mostly
photochromic) thin films of polymeric liquid crystals. The alignment control of liquid crystal that is essential inliquid crystal photonics can be achieved by irradiation with linearly polarized light to the surface photoresponisve
layer on a substrate or a free surface. Based on this phenomenon, we are extending the possibilities ofphotoalignment process for orientation control of various functional materials.

Affiliation : Professor of the Graduate School of Engineering / Director of Institute of Nano-Life-Systems
Research Field : nanobioscience, biomedical engineering

Yoshinobu
BABA
Steering Committee

Research Interests
The research efforts in my laboratory have been focused on the development of nanobiodevices for biomedical
applications and healthcare, including single cancer cell diagnosis for cancer metastasis, circulating tumor cell (CTC)
detection by microfluidic devices, nanopillar devices for ultrafast analysis of genomic DNA and microRNA,
nanopore devices for single DNA and microRNA sequencing , nanowire devices for exosome analysis,
single-molecular epigenetic analysis, AI-powered nano-IoT sensors, quantum switching intra vital imaging of iPS cells
and stem cells, and quantum technology-based cancer theranostics.

March 2021 | IAR LETTER | 26

IAR PEOPLE | IAR Core Faculty Committee / IAR Steering Committee 2020

Steering Committee

I am working in the field of cosmology to understand dark components in the Universe. The Universe is
known to consist of various components including atoms, photons, dark matter and dark energy. The ultimate
goal of modern cosmology is to understand the nature of dark matter and dark energy. Since dark matter plays
an essential role for the formation of structure through gravity, and dark energy controls expansion of the
Universe itself, both have significant impact on structure formation in the Universe. Utilizing the observation
data of structure of the Universe, including galaxies, clusters of galaxies, large-scale structure of the Universe,
and temperature fluctuations of cosmic microwave background radiation, which is a fossil of big bang in thevery early Universe, I try to reveal the nature of dark matter and dark energy.

Affiliation : Professor of the Graduate School of Economics
Research Field : History of Science and Technology

SayakaOKI
Steering Committee

Research Interests
History of Science in the 17-18th century of France, especially on the relationship between the government andacademic institutions of science; Concept of "Economy" and its relationship with natural sciences in the latter
half of the 18th century

IAR
Visiting Professor & Designated Professor

TakahoANDO

IAR PEOPLE | IAR Steering Committee / IAR Visiting Professor / YLC Program Faculty 2020

Visiting Professor

Affiliation : Visiting Professor at Nagoya IAR / Professor at Chubu University
Research Field : History of Social Thoughts

Research Interests
Research on History of Social Thoughts, especially on French Enlightenment and Liberalism.

Affiliation : Visiting Professor at Nagoya IAR
Research Field : Medieval Japanese Culture and Texts

YasuroABE
Visiting Professor

Research Interests
My research focuses on the religious texts of medieval Japan, emphasizing their context as objects of religious
cultural heritage. I have strived to demonstrate how religious texts, images, and other objects have been used,transmitted, and understood from the Middle Ages through the present day. Through the analysis of concrete
examples—such as the cult of Prince Shōtoku, and various conceptions of the "sacred" in medieval Japan—I
have demonstrated that these texts mutually interact not only with each other, but also with external works ofliterature, performative arts, and iconography.

Affiliation : Visiting Professor at Nagoya IAR / Professor at Nanzan University
Research Field : International Economics

DapengCAI
Visiting Professor

Research Interests
An increasing number of challenges facing humanity today, such as the reduction of the emission of thegreenhouse gases, or the protection of global commons, all require intensive cooperation by many countries. My
research aims at analyzing the international negotiation processes that are underlying the formation of theneeded international cooperation. Besides the issue of emission reductions, I also examine other issues that
require international negotiations-in particular, those between the North and the South-such as the protectionof intellectual property rights, as well as the setting of investment rules or production standards.

Affiliation : Visiting Associate Professor at Nagoya IAR
Research Field : Plant Physiology, Zinc Biology

Miki
KAWACHIVisiting Associate
Professor

YLC
Program Faculty

Tomohiro
ABE
Young Leaders
Cultivation Program
Faculty(YLC)

27 | IAR LETTER | March 2021

Research Interests
My research mainly concerns the transport of micro-nutrients in living organisms. All organisms need elements
like zinc or manganese in very minute amounts, however, even a small excesses can be harmful. Specialized
transport proteins are the principal means of nutrient movement within and between cells. I am interested in
the structure of those proteins and how structural differences might affect their function. I am working withdiverse model organisms ranging from microbes to all the way to fruit trees.

YLC Faculty members are promising young researchers recruited under the
Nagoya University Young Leaders Cultivation Program (YLC Program).

Affiliation : Designated Assistant Professor at Nagoya IAR and Graduate School of
Kobayashi Maskawa Institute (KMI)
Research Field : elementary particle physics
Research Interests
My interest lies in physics beyond the standard model of elementary particles. One of my current research topics
is dark matter. I have been revisiting a calculation of the dark matter energy density in models widely studied in
the particle physics community. I found that dark matter-Higgs coupling should be much larger than the value
obtained in the previous works. This result is testable by studying the decay process of the Higgs boson into
dark matter particles. I have also been working on physics on the Higgs boson(s) with focusing
on various ongoing and planned experiments in the future.

Masaru
TAKEUCHI
Young Leaders
Cultivation Program
Faculty(YLC)

Kazuhide
SATO
Young Leaders
Cultivation Program
Faculty(YLC)

Affiliation : Designated Assistant Professor at Nagoya IAR and Graduate School of Engineering
Research Field : Micro-nano manipulation
Research Interests
My research interests are micro-nano manipulation, microfluidics and optoelectronic devices for biologicalapplications. Especially, developments of small devices for three dimensional assembly of cell structures using
self-assembly process has been conducted. Micromanipulation devices using solid-liquid phase change were also
developed to handle single cells, or actuate small amount of liquid. The assembled 3D cell structures by thedeveloped devices will be used as in vitro models of our organs.

Affiliation : Designated Assistant Professor at Nagoya IAR and Graduate School of Medicine
Research Field : Respiratory Medicine, Oncology
Research Interests
Lung cancer is the most common cause of cancer-related deaths, and the cure rate of lung cancer is still under
20%, therefore, there is urgent need for new treatments. I aim to develop new innovative cancer therapy with aconcept "less toxic, more anti-tumor effect". Along with different approaches from conventional cancer
therapies, I have been studying about photo-activated cancer therapy in order to destroy only cancer cells
inside body. I would like to develop new technologies that could cause effects only on the cancers with amultidisciplined approach.

Affiliation : Designated Assistant Professor at Nagoya IAR and Graduate School of Science
Research Field : Particle Physics, Astrophysics

Young Leaders
Cultivation Program
Faculty(YLC)

Research Interests
A fundamental particle "neutrino" is a key for revealing the origin of the matter dominated universe. I havecarried out accelerator based neutrino experiments with nuclear emulsion detector. So far we provided the final
evidence of nu_mu -> nu_tau neutrino oscillation with tau neutrino appearance in a muon neutrino beam from
CERN in the OPERA experiment. Then I have established and am promoting a new experimental project(NINJA Experiment) to measure neutrino interactions precisely at J-PARC as the PI. Precise measurement of
neutrino-nucleus interactions is essential for observing the neutrino-CP violation which is an important hint
for matter-antimatter asymmetry in our universe.

Affiliation : Designated Assistant Professor at Nagoya IAR and Graduate School of Science
Research Field : Astropysics, Planetary Science

Yuri
FUJII
Young Leaders
Cultivation Program
Faculty(YLC)

Hidenori
TAKEUCHI
Young Leaders
Cultivation Program
Faculty(YLC)

Research Interests
I am working on the formation theory of planets and satellites in our solar system and also in extrasolar systems.
Planets form in gaseous disks called protoplanetary disks, which are the leftover of star formation. Recent
observations show wide variety of structures in protoplanetary disks including the clue of ongoing planet
formation. I perform magneto-/radiation hydrodynamic simulations to investigate the dynamics ofprotoplanetary disks and the manner of the gas flow onto a planet in the disk. These simulations provide theformation environments for planets and satellites. I am also interested in chemical evolution of protoplanetarydisks, modeling of circumplanetary disks, and orbital evolution of satellites.

Affiliation : Designated Assistant Professor at Nagoya IAR and Institute ofTransformative Bio-Molecules (ITbM)
Research Field : Molecular biology in plant reproduction
Research Interests
Fertilization between male and female gametes of the same species is fundamental for seed production andspecies maintenance in higher plants. My research interests are in species-specific male-female recognition
mechanisms, including prezygotic pollen tube guidance and postzygotic chromosome maintenance. I will
especially try to identify key factors involved in these processes. I finally aim to understand the species-specificmechanisms in plant reproduction, which could lead to technologies for generating useful hybrid plants.

Affiliation : Designated Assistant Professor at Nagoya IAR and Graduate School of Science
Research Field : Cosmology, Weak Gravitational Lensing

Hironao
MIYATAKE
Young Leaders
Cultivation Program
Faculty(YLC)

Research Interests
My research interests lie in observational cosmology. Cosmic acceleration discovered in the late 1990s is one of
the most mysterious phenomena in physics and astronomy, which indicates the existence of dark energy or themodification to general relativity. I have been working on exploiting weak lensing observables, the subtle
distortion in the shapes of distant galaxies due to massive foreground structures, to extract the nature of cosmic
acceleration from big imaging data taken by Hyper Suprime-Cam (HSC) at the Subaru Telescope. I am also
involved in upcoming international galaxy surveys such as Large Synoptic Survey Telescope (LSST) andNASA's Wide Field Infrared Survey Telescope (WFIRST).

March 2021 | IAR LETTER | 28

IAR PEOPLE | YLC Program Faculty 2020

Tsutomu
FUKUDA

Affiliation : Designated Assistant Professor at Nagoya IAR and Kobayashi-Maskawa Institute (KMI)
Research Field : Particle Physics, Astroparticle Physics

ShingoKAZAMA
Young Leaders
Cultivation Program
Faculty(YLC)

TeppeiKITAHARA
Young Leaders
Cultivation Program
Faculty(YLC)

IAR PEOPLE | YLC Program Faculty 2020

Yuki
SATO
Young Leaders
Cultivation Program
Faculty(YLC)

Natsuki
TAKADATANAKA
Young Leaders
Cultivation Program
Faculty(YLC)

Research Interests
Despite the overwhelming evidence for dark matter from astronomical and cosmological indications at various
scales, a clear evidence of a particle which explains these observations remains absent. I'm involved in the
XENON project to search for the low-energy interactions of galactic dark matter with nuclei. The XENON
collaboration has built the XENON1T detector, the most sensitive detector ever built, but no clear evidencesof dark matter have been found. We are currently upgrading the XENON1T detector by enlarging the target
xenon mass from 2 to 6 tonnes. The new experiment will start its operation in 2019, and this will allows us to
explore promising parameter spaces towards a first discovery.

Affiliation : Designated Assistant Professor at Nagoya IAR and Kobayashi-Maskawa Institute (KMI)
Research Field : High energy physics, Flavor physics
Research Interests
I am interested in searching for physics beyond the standard model through precision measurements of theproperties of standard model particles, and especially my main focus is on flavor physics. I am going to improve
the standard model predictions of B-meson decays and also investigate CP violation in rare kaon decays. I am
broadly interested in testable physics of various experiments, and I hope to stimulate interactions between
theory and experiment.

Affiliation : Designated Assistant Professor at Nagoya IAR and Graduate School of Science
Research Field : Quantum gravity
Research Interests
Modern physics incorporates Einstein's general relativity and quantum mechanics. The former associates gravity
with the bending of spacetime, and the latter explains characteristic properties of matters at short distances.
According to general relativity, the spacetime curves due to the existence of matters, and matters indicate
quantum characteristics at short distances. Therefore, gravity is supposed to show quantum mechanical effects,
and those effects would become important around the Planck scale. The theory that describes quantum effects ofgravity, quantum gravity, is my field of research. I mainly study discrete approaches to quantum gravity.

Affiliation : Designated Assistant Professor at Nagoya IAR and Graduate School of Bioagricultural Sciences
Research Field : Plant Molecular Physiology, Biochemistry
Research Interests
Plants live in a frequently changing environment from which they cannot escape and have signaling mechanisms
to adapt to new conditions. Calcium, lipid and protein are involved in the signaling pathways. However,limited information on signal transduction between different signaling systems is available. I focus on a new
type signal transducer PCaP1 which can convert Ca2+ signal to phospholipid signal on plasma membrane.
Thus I investigate PCaP1-related physiological processes, such as stomata closure and root hydrotropism, toreveal a novel mechanism to adapt a new environmental conditions.

Affiliation : Designated Assistant Professor at Nagoya IAR and Graduate School of Humanities
Research Field : International Relations in 17-19th century East Asia

Yongchao
CHENG
Young Leaders
Cultivation Program
Faculty(YLC)

Hiroki
FUJINO
Young Leaders
Cultivation Program
Faculty(YLC)

29 | IAR LETTER | March 2021

Research Interests
By putting Joseon Korea as a mediator between Tokugawa Japan and Ming-Qing China, which have notestablished formal diplomatic relation in 17-19th centuries, I demonstrate and empirically analyze, that China
and Japan had mediated political connections, aiming to rebuild the history of East Asia by using the approachof global history. Instead of just adding up of several bilateral relations, such as Japan-Korea and Korea-China, I
am putting the historical pieces scattered in Chinese, Japanese, Korean documents together and confronting
simultaneously the trilateral relation of countries, to illuminate the entanglements and interactions among
early-modern East Asian countries.

Affiliation : Designated Assistant Professor at Nagoya IAR and Graduate School of Mathematics
Research Field : complex analysis, function theory
Research Interests
My research topic is on the global properties of the infinite dimensional Teichmuller spaces. In particular, I am
mainly interested in degeneration phenomena of Riemann surfaces on the boundaries of the Teichmuller spaces.
The Teichmuller space is a space which parametrizes all quasiconformal deformations of a given surface. If thegiven surface is of finite type, the degenerations to nodal surfaces appear as a dense subset of the boundary.
However, in the case of infinite type surfaces, various degeneration phenomena are obtained besides thedegenerations to nodal surfaces.

Soon-Ki
HAN
Young Leaders
Cultivation Program
Faculty(YLC)

Affiliation : Designated Assistant Professor at Nagoya IAR and Institute of Transformative
Bio-Molecules (ITbM)
Research Field : Plant stomata development
Research Interests
Plant stomata are cellular valves surrounded by a pair of guard cells that impact plant growth, sustenance, andatmospheric environment. Stomatal stem cells are produced and transiently amplified on the leaf surface, andtheir stem cell activity is terminated before differentiation. I aim to understand the direct roles of transcription
factors in a dynamic alteration of gene expression that is responsible for stomatal differentiation especially inmaintenance and termination of stomatal lineage stem cells.

Affiliation : Designated Assistant professor at Nagoya IAR and Graduate School of Environmental Studies
Research Field : Human Geography, Areal Studies

Ai
SUGIE
Young Leaders
Cultivation Program
Faculty(YLC)

Young Leaders
Cultivation Program
Faculty(YLC)

KazuyaFUJIMOTO
Young Leaders
Cultivation Program
Faculty(YLC)

Yoko
MIZUTA
Young Leaders
Cultivation Program
Faculty(YLC)

Koji
MURATA
Young Leaders
Cultivation Program
Faculty(YLC)

Affiliation : Designated Assistant professor at Nagoya IAR and Division for Integrated Studies,
Institute for Space-Earth Environmental Research
Research Field : Solar Physics, Space Weather
Research Interests
Solar eruptions, such as "solar flares" and ''coronal mass ejections (CMEs)" are sometimes impact to spaceenvironment around the Earth. However, onset mechanisms and propagation processes of those phenomena are
not yet revealed. Therefore, our ability of "space weather forecast", which predict disturbances of spaceenvironment near the Earth, does not satisfy requirements from modern society, which rapidly promote spacedevelopment. I aim to understand the onset and propagation processes of solar eruptions by comparison ofvarious observational data and numerical modelings.

Affiliation : Designated Assistant professor at Nagoya IAR and Department of Applied Physics,
Graduate School of Engineering
Research Field : Condensed matter physics (theory)
Research Interests
Non-equilibrium phenomena emerge in various length-scales ranging from small atomic and molecular clusters
to fluid dynamics in our daily life. I have been interested in universal aspects of non-equilibrium phenomena,and have recently studied relaxation dynamics, wave and vortex turbulence, and chaos in ultracold quantum
gases. The system is a vapor of several atomic species at very low temperature, and is recognized as one of thepromising playgrounds for studying such non-equilibrium phenomena in quantum many-body systems.

Affiliation : Designated Assistant professor at Nagoya IAR and Institute of Transformative
Bio-Molecules (ITbM), Nagoya University
Research Field : Molecular biology, Plant reproduction
Research Interests
In the flowering plants, sexual reproduction occurs in a flower. In the flower, pollen lands on the female tissue,
and pollen germinates pollen tube and deliver the sperm to the egg cell. After that, fertilization occurs. During
this process, it is necessary to fertilize without waste both males (pollen tubes) and females (ovules) to produce
more seeds in nature, but the whole picture of such precise plant fertilization mechanism is unclear. To
understand this mechanism, two-photon imaging, expression and phylogenic analyses will be performed. I
developed deep-and live-imaging technics using two-photon microscopy. The pollen tube mediated genemodification technology is also developed.

Affiliation : Designated Assistant professor at Nagoya IAR and Institute for Advanced Research /Graduate School of Humanities
Research Field : History, Byzantine Studies, Diplomatics
Research Interests
I am interested in various subjects related to Byzantium, the Medieval Roman Empire (ca. 4th Century to1453). My current research explores social functions of byzantine documents issued by emperors and state
officials in the 13th and 14th centuries. In particular I am investigating to what extent written documents were
utilized to regulate relationships between Byzantium and other polities.

March 2021 | IAR LETTER | 30

IAR PEOPLE | YLC Program Faculty 2020

Yumi
BAMBA

Research Interests
Bangladeshi Migrants in Saudi Arabia and transnational networks of Islamic Revival. This study explores thesocio-spatial structure and socio-economic backgrounds of Bangladeshi migrants in Makkha and examines theirsocial-cultural impacts on Islamic revival movements in the city and their hometowns in Bangladesh. Research
2: Pluralistic economy and alternative development. This study discusses the possibility of an alternative
development based on a pluralistic economic system that reciprocity among people and between human andnature are prioritised over market economy success. Research 3: Water resources problems in Rohingya refugee
camp areas in Bangladesh.

AaronCHAN

Affiliation : Designated Assistant professor at Nagoya IAR and Graduate School of Mathematics
Research Field : Representation theory, category theory
Research Interests

Young Leaders
Cultivation Program
Faculty(YLC)

I research in the representation theory of algebras and related structures, which originates from theapproximating (i.e. `representing') abstract mathematical objects using linear algebra. I am particularlyinterested in tilting theory. This studies different methods in modifying a category of representations in a waythat preserves homological properties. I am also involved in a similar theory-cluster-tilting theory-which is atheory in the algebraic analogue of resolution of singularities.

Claudia
MARTINEZCALEDERON

Affiliation : Designated Assistant professor at Nagoya IAR and Institute for Space–Earth Environmental Research
Research Field : Magnetosphere and Space Plasma Physics

Young Leaders
Cultivation Program
Faculty(YLC)

IAR PEOPLE | YLC Program Faculty 2020

AngelaMENESESGUTIERREZ
Young Leaders
Cultivation Program
Faculty(YLC)

Chihiro
INOSE
Young Leaders
Cultivation Program
Faculty(YLC)

Research Interests
My research project focuses on VLF/ELF emissions, their physical properties, generation and propagation.
Currently my focus is on ground and satellite simultaenous and conjugated VLF events. I'm also an active
member of the VERSIM workshop group and co-founder of their Journal Club.

Affiliation : Designated Assistant professor at Nagoya IAR and Disaster Mitigation Research Center
Research Field : Crustal deformation
Research Interests
I study crustal deformation through geodetic observations (Global Navigation Satellite Systems (GNSS),
Interferometric Synthetic Aperture Radar (InSAR), etc.), focusing on the analysis of earthquake-related
processes. I am interested in distinguishing strain accumulation due to elastic processes in the Earth, released in
the form of large earthquakes, from inelastic processes which are irreversible and cause strain to accumulate overgeological time.

Affiliation : Designated Assistant professor at Nagoya IAR and Graduate School of Humanities
Research Field : History and Culture of Japan

Research Interests
My main research object is Japanese culture from the 12 century to the 15 century. I'm particularly interested inmusic performed in rituals. Many old Japanese music is not played now. However, musical scores still remain.
The purpose of my research is to reconstruct music from these scores and to clarify the characteristics between
music and rituals.

Affiliation : Designated Assistant professor at Nagoya IAR and Graduate School of Science
Research Field : Astrophysics

DaichiKASHINO
Young Leaders
Cultivation Program
Faculty(YLC)

Shunsuke
KOSAKA
Young Leaders
Cultivation Program
Faculty(YLC)

31 | IAR LETTER | March 2021

Research Interests
The present-day Universe contains a variety of elements and is a rich world in which stars, galaxies, and life
exist. I aim to understand the material evolution in the Universe. We are especially paying attention to aphenomenon called cosmic reionization that completed until about 1 billion years after the Big Bang. Cosmic
reionization is a phenomenon in which the Universe, which was initially filled with electrically neutralhydrogen gas, was ionized by the ultraviolet rays emitted by stars and galaxies born in the early Universe, and is
the first step in material evolution. We are carrying out various observations using large telescopes tounderstand the physical process of reionization.

Affiliation : Designated Assistant professor at Nagoya IAR and Graduate School of Humanities
Research Field : History, Ancient Roman, Late Antiquity
Research Interests
I am studying the history of the Roman Empire in Late Antiquity (c. 3rd to 8th centuries CE). My researchsubject is a historiographical work written by Ammianus Marcellinus (late 4th century) and the city of Rome,
where the author lived and composed his writings. I am trying to clarify the social and political background of
the text as well as the author’s view against them.

Tomoya
NAKAYAMA
Young Leaders
Cultivation Program
Faculty(YLC)

Affiliation : Designated Assistant professor at Nagoya IAR and Graduate School of Bioagricultural Sciences
Research Field : Animal physiology, Molecular biology
Research Interests
In temperate zones of the earth, dynamic environmental fluctuations occur at the annual seasonal cycle. To copewith these seasonal changes, many animals adapt their physiology and behavior. Although some of theseseasonal activities, such as reproduction, growth and hibernation are known to be controlled by endogenous
annual rhythmicity, which is called circannual rhythm, in some animals, the molecular mechanism is still
unknown. We use medaka fish as a model to understand this mechanism.

Affiliation : Designated Assistant professor at Nagoya IAR and Graduate School of Bioagricultural Sciences
Research Field : Fish Neuroscience

HanakoHAGIOYoung Leaders
Cultivation Program
Faculty(YLC)

Research Interests
Two ascending visual pathways to the telencephalon are present in mammals. However, some species of fish
possess two visual pathways, while others one pathway. Our studies in several fish species suggest that thecommon ancestor of actinopterygians possessed two pathways, and later one pathway was lost in the common
ancestor of acanthopterygians, which include many fishes for fisheries. We try to elucidate functions of visual
pathways using genome editing and microscopic live imaging analyses on visually-evoked neural activities. We
would like to find visual stimuli attractive for fishes and utilize its characteristics in fishing gear to contribute to
the academic field and fisheries industry.

Affiliation : Designated Assistant professor at Nagoya IAR and Institute for Space-Earth Environmental Research
Research Field : Space Weather, History, Solar Activity

Young Leaders
Cultivation Program
Faculty(YLC)

ManabuBESSHOUEHARA
Young Leaders
Cultivation Program
Faculty(YLC)

Toshiki
MATSUSAKA
Young Leaders
Cultivation Program
Faculty(YLC)

Research Interests
Hisashi Hayakawa is working on historical space weather events and long-term solar activity based on thecontemporary analog records. He consults analog records for sunspots, solar flares, geomagnetic measurements,
and auroral sightings to reconstruct chronology and intensity of the space weather events, namely sequence of
solar flares, interplanetary coronal mass ejections, geomagnetic storms, and auroral displays. He also analyses
historical sunspot records to quantitatively reconstruct and improve long-term solar variability. Thus hechronologically extends the time series of the existing scientific databases for centuries and quantitatively
contextualises the modern data into longer time series.

Affiliation : Designated Assistant professor at Nagoya IAR and Graduate School of Science
Research Field : Biology, Evolution, Bioluminescence
Research Interests
Bioluminescence, light production by living organisms, is one of the most common traits of the animals on the
Earth (75-90% of macroscopic individuals in the ocean can emit light). Bioluminescence evolved among diverse
taxa independently, which is the best model to study evolution. The molecular mechanisms involved in thelight emission are poorly understood except for a few well-studied animals. In addition, I recently discovered
kleptoprotein, stealing protein from the prey, for bioluminescence. I study the molecular mechanisms involvedin the luminescent reaction, luciferin and luciferase, to understand extreme convergent evolution of
bioluminescence.

Affiliation : Designated Assistant professor at Nagoya IAR and Graduate School of Mathematics
Research Field : Number theory
Research Interests
Modular forms are vital objects in classical and modern mathematics. This theory plays a crucial role as a bridge
between number theory, topology, harmonic analysis, arithmetic geometry, combinatorics, representation
theory, mathematical physics, etc. My research interest is investigating the roles of its generalization called“non-holomorphic modular forms” in this wide range of fields. In particular, I have been working on it from theviewpoints of number theory and knot theory.

Affiliation : Designated Assistant professor at Nagoya IAR and Graduate School of Science
Research Field : Particle physics and astrophysics

QidongZHOU
Young Leaders
Cultivation Program
Faculty(YLC)

Research Interests
Dark matter, matter dominance universe, there are phenomena still could not be explained by the current
framework of theory in particle physics, the standard model (SM). To explore the new physics beyond standard
model, it is a useful approach to precisely measure the decay reactions under the environment just like thebeginning of our universe which is created by colliding-beam accelerator. Belle II is an experiment dedicated to
explore new physics beyond SM based on this approach. It has already started collecting data since April 2018. I
am preforming the detector upgrade and data analysis in parallel. In coming years, these data will help us tounderstand the origins of matter and the universe.

March 2021 | IAR LETTER | 32

IAR PEOPLE | YLC Program Faculty 2020

Hisashi
HAYAKAWAI
INFORMATION
Owing to COVID-19 concerns, most annual plans havebeen canceled or postponed. However, Nagoya University's
Institute of Advanced Research (IAR) has launched several
online seminars in 2020.

IAR Symposium
IAR Symposiums are aimed at communicating theestablished, novel, and cutting-edge research of Nagoya
University to all of its members. Usually, we focus on two
different fields: literature and social science, and natural scienceand engineering. June 6, 2020, IAR and the Institute of
Innovation for Future Society jointly hosted a special online
symposium, titled “Look into the Future—How Do Researchers
Overcome the COVID-19 Crisis.” Six professors were selected as
faculty representatives to give lectures on their respective
specialties, practical problems, and experiences during the
lockdown.The second symposium of this series, which centeraround literature and social science, held on January 22, 2021.
The title of this symposium is “Worth and Contribution of
Academic Discipline—Impacts of the Research and Dialogs.” We
had guest speaker Dr. Susumu ANNAKA from the Waseda
Institute for Advanced Study (WIAS). Three researchers from
Nagoya University gave talks.

Activities & News
“Dialogue.” Directors presented their activities for UBIAS andengaged in active discussions.

2020 Young Leaders Cultivation Program
The Young Leaders Cultivation (YLC) Program is a strategic
program of Nagoya IAR based on the premise that it is crucial
to secure an appropriate quantity and quality of young
re s e a rc h e rs i n o rd e r to s u sta i n t h e d e ve l o p m e nt o foutstanding education and research in the future. Nagoya IAR
recruits and trains young faculty members regularly andsystematically. In the academic year 2020, Dr. Chihiro INOSE(Graduate School of Humanities), Dr. Daichi KASHINO(Graduate School of Science), Dr. Shunsuke KOSAKA (Graduate
School of Humanities), Dr. Tomoya NAKAYAMA (Graduate
School of Bioagricultural Sciences), Dr. Hanako HAGIO(Graduate School of Bioagricultural Sciences), Dr. Hisashi
HAYAKAWA (Institute for Space-Earth Environmental
Research), Dr. Manabu BESSHO-UEHARA (Graduate School of
Bioagricultural Sciences), Dr. Toshiki MATSUSAKA (Graduate
S c h o o l o f M a t h e m a t i c s ) , a n d D r. Q i d o n g Z H O U(Kobayashi-Maskawa Institute for the Origin of Particles andUniverse) were newly employed as designated assistantprofessors of the YLC program.

YLC Seminar

UBIAS Directors' Pre-Conference 2020
On October 12–14, 2020, University-Based Institutes for
Advanced Study's (UBIAS's) online conference participated bydirectors worldwide was held. The University of São Paulo and
The University of Western Australia organized the meeting.
Nagoya IAR has played a central role as a steering committee of
UBIAS. Dr. Suto, Director of Nagoya IAR, gave a talk on the Topicof the Year for 2020 and 2021. The UBIAS member institutes
decided that the Topic of the Year for 2020 and 2021 was

33 | IAR LETTER | March 2021

The YLC seminar is aimed at providing members with
opportunities to understand each other's research interests toassist interdisciplinary collaboration research. The 22nd YLC
Seminar was held on October 27 2020. Dr. Hiroki Fujino (YLC
Assistant Professor of Nagoya IAR/Graduate School ofMathematics) discussed “How to make complicated Surfaces?”and Dr. Yongchao Cheng (Associate Professor of Tohoku
University/ Former YLC Faculty) talked about “Japan’s diplomaticnegotiation with Ming China via Tsushima Domain and Joseon
Dynasty in the first half of the seventeenth century.” The 23rd
YLC Seminar was held on December 22 2020. Dr. Yoko Mizuta( Y LC A s s i sta n t P ro fe s s o r o f N a g o ya I A R / I n st i t u te o f
Transformative Bio-Molecules) discussed “Colorful Imaging of
the Secret Life of Plants,” whereas Dr. Hironao Miyatake (YLC
Assistant Professor of Nagoya IAR/Graduate School of Science)talked about “Shedding Light on Dark Sector of the Universe by
Weak Gravitational Lensing.” The 24th YLC Seminar was held on
March 23 2021. Dr. Hisashi Hayakawa (YLC Assistant Professor of
Nagoya IAR/Institute for Space-Earth Environmental Research)
discussed “Tentative reconstructions of extreme space weather
events using historical archival records,” and Dr. Manabu
Bessho-Uehara (YLC Assistant Professor of Nagoya IAR/Graduate

I.A.R. INFORMATION

School of Science) talked about “How a fish steals a light fromits prey.” Active discussions took place.

6. “How to Use Contemporary Economics,”
by Professor Jiro Nemoto（Graduate School of Economics）
7. “Visualize—Science About the Blessing of Nature,”by Professor Ryo Kohsaka（Graduate School of Environmental Studies）

8. “Analyze Democracy,”by Professor Hiroko Takeda（Graduate School of Law and Deputy Director of Nagoya IAR）

9. “Fascination with an Introduction to the History of Thought,”
by Professor Takaho Ando（Chuo University/Sixth Director of Nagoya IAR）
10.“Next-Generation Bio-imaging,”by Professor Shigehiro Yamaguchi（Graduate School of Science and Institute of Transformative Bio-Molecules）

11. “Genome Breeding to Solve the Food Crisis,”by Professor Makoto Matsuoka（Graduate School of Bioagricultural Sciences）
´$UH&KHPLFDOO\5HDFWLQJ0ROHFXOHV¶9LVLEOH·"µby Professor Akiyoshi Hishikawa（Research Center for Material Scienc）
13.“Chemistry of Anthocyanin—Make It Bloom the Blue Roses,”by Professor Kumi Yoshida（Graduate School of Informatics）
´+RZ,VWKH%UDLQ)RUPHG"5HVHDUFKRQ&HOO'HYHORSPHQWµby Professor Takaki Miyata（Graduate School of Medicine）

YLC Collaborative Research Grant
The YLC collaborative research grant was launched in2018 to support interdisciplinary collaboration between YLC
faculty. YLC faculty voluntarily organized the grant contents,
schedule, and selection process. YLC selected two researchgroups for a year. One of the chosen groups was represented
by Dr. Yuri Fujii (YLC Assistant Professor of Nagoya IAR/
Graduate School of Science); the project title was“Astronomical Phenomena in Historical Literature.” The othergroup was represented by Dr. Hisashi Hayakawa; the project
title was “Feasibility Researchers on the Quantitative
Environmental History: a Case Study for the Crisis of the 17th
Century and Its Comparison with Other Historical Crises.”

IAR Freshmen Lecture Series
Targeting first-year students of the Nagoya University,
this lecture series includes lectures delivered by members of
the IAR Academy, IAR Faculty members, IAR Fellows, andNagoya University researchers. The series was aimed atcommunicating the fun of academic research. In the academic
year 2020, the following 14 lectures took place online:

Foreign PI Fellowship Program
The Foreign Principal Investigator (PI) Fellowship Programis a program that invites excellent researchers from foreigncountries with outstanding research achievements for 3 to 4
months' fellowship to promote the University's academic
research. In the academic year 2020, Dr. Olga Riklikiene (Professor of Lithuanian University of Health Sciences) and Dr. Yi-Fang
Tsay (Distinguished Research Fellow of Academia Sinica) wereselected for this fellowship. While they were visiting Nagoya
University, they discussed collaborative research with PIs at
Nagoya University.
They also contributed to the educationof young researchers by giving advice
Dr. Yi-Fang Tsay
Dr. Olga Riklikiene
and lectures.

Awards

1. “Science Started from Observation,”

D r. H i t o s h i S a k a k i b a r a (P r o f e s s o r o f G r a d u a t e S c h o o l o f
Bioagricultural/Deputy Director of Nagoya IAR) received the Enid
MacRobbie Corresponding Membership Award (American Society ofPlant Biologists) (July 2020) and was recognized by Clarivate Analytics as
one of its Highly Cited Researchers (November 2020).

2. “The Research History of Particle Physics,”
by Professor Makoto Kobayashi

Dr. Kazuhide Sato (YLC Assistant Professor of Nagoya IAR/Graduate

by Professor Sumio Iijima（Guest Professor of Nagoya University and Professor of Meijo University）（Director of the Kobayashi Maskawa Institute and 2008 Nobel Laureate in Physics）

3. “The Dark Matter of the Universe,”

by Professor Naoshi Sugiyama（Graduate School of Science, Director of NAIAS and Vise-President of Nagoya university）

4.“Material Science—Fun and Useful,”
by Professor Ichiro Terasaki（Graduate School of Science and Deputy Director of Nagoya IAR）

5. “The Present in Historical Studies: Excavate the Hellenism Civilization,”by Professor Yoshiyuki Suto（Graduate School of Humanities, Director of Nagoya IAR）

School of Medicine) won the 47th Hyper Interdisciplinary Conference
Research Award (April 2020), the Japanese Society of Chemotherapy's
5th Uehara Infection and Chemotherapy Research Award (September2020), T he Young Inves ti gator Awards of the Japanese C ancer
Association (Clinical) (October 2020), The 7th Young Investigator Awardsof the Japan Society of Infrared Science and Technology (October 2020),
and Mycosis Forum 2020 B es t Present ation Award (Novemb er2020).uate School of Science) won the Konica Minolta Photographic
Science Encouragement Award (Jul. 2019).

March 2021 | IAR LETTER | 34

INSTITUTE FOR ADVANCED RESEARCH, NAGOYA UNIVERSITY
Telephone. +81-52-788-6051 Facsimile. +81-52-788-6151 E-mail. nu-iar@adm.nagoya-u.ac.jp
http://www.iar.nagoya-u.ac.jp/