bluuebunny/crossref_metadata_2025 huggingface dataset:
Ionization and acceleration of multiply charged gold ions in solid film irradiated by high intensity laser
Authors: Kawahito D. , Kishimoto Y.
Published: March 2020

In this paper, we present the mechanisms of ionization of a thin gold film irradiated by a high-intensity, short-pulse laser in the range of I=1020−22 W/cm2 and the associated acceleration of multiply charged gold ions. A numerical one-dimensional simulation using an extended particle-in-cell code, which includes atomic and collisional relaxation processes, indicates that two types of acceleration, hole-boring radiation pressure acceleration (RPA) and target normal sheath acceleration (TNSA), contribute to the generation of highly charged ions with kinetic energies on the order of 10 MeV/u. In each acceleration, a longitudinal electrostatic field excited by different mechanisms dominantly ionizes atoms to higher charge states and accelerates them to the vacuum region from the rear surface, which is opposite the front surface irradiated by the laser field. The field ionization process dominantly ionizes high energy ions to the high charge state, while a large number of ions with energy <1 MeV/u are ionized by an electron impact ionization process. In TNSA, a multiply charged ion generated at the rear surface is accelerated to the maximum energy although the ion with the highest charge state is generated at the front surface in RPA. However, the existence of contamination, such as water vapor, suppresses the ion energy of TNSA to less than that of RPA since the sheath field readily accelerates the protons and oxygen prior to the acceleration of the gold ions. Our derived theoretical scaling describes the maximum ion energy for each charge state in the cases with and without contamination using the relationship between the longitudinal electrostatic field profile near the rear surface and the classical tunnel field ionization model.
Snell's law for spin waves at a 90° magnetic domain wall
Authors: Hioki Tomosato , Tsuboi Rei , Johansen Tom H. , Hashimoto Yusuke , Saitoh Eiji
Published: March 2020

We report the experimental observation of the refraction and reflection of propagating magnetostatic spin waves crossing a 90° domain wall (DW). Time-resolved magneto-optical imaging was used to observe the propagation dynamics of magnetostatic spin waves. Due to the magnetization rotation across such a DW, the dispersion relation of magnetostatic spin waves rotates by 90°. This results in a change in the propagation dynamics of spin waves on both sides of the DW. We observed the refraction and reflection of magnetostatic spin waves at the DW and reveal their characteristics that include negative refraction. The incident-angle dependence of the refraction angle is explained by the wavenumber conservation along the DW, quite similar to the case of Snell's law for light.
Epitaxial growth and orientation-dependent anomalous Hall effect of noncollinear antiferromagnetic Mn3Ni0.35Cu0.65N films
Authors: Miki R. , Zhao K. , Hajiri T. , Gegenwart P. , Asano H.
Published: March 2020

We report the growth of noncollinear antiferromagnetic (AFM) Mn3Ni0.35Cu0.65N films and the orientation-dependent anomalous Hall effect (AHE) of (001) and (111) films due to the nonzero Berry curvature. We found that post-annealing at 500 °C can significantly improve the AHE signals, though using the appropriate post-annealing conditions is important. The AHE and magnetization loops show sharp flipping at the coercive field in (111) films, while (001) films are hard to saturate by a magnetic field. The anomalous Hall conductivity of (111) films is an order of magnitude larger than that of (001) films. The present results provide not only a better understanding of the AHE in Mn3XN systems but also further opportunities to study the unique phenomena related to noncollinear AFM.
The effect of a multi-fracture compression airflow arc-extinguishing structure interrupting the power frequency follow current
Authors: Huang Shangshi , Wang Jufeng , Xu Yuheng , Li Zijian , Yan Renbao , Zhang Qixing
Published: March 2020

To reduce the damage from the power frequency follow current of distribution lines, a multi-fracture compression airflow arc-extinguishing structure is studied. The structure is mainly composed of a compression tube, a metal electrode, and metal connection fittings, and the multi-fracture compression airflow arc-extinguishing body is formed by the combination of packaging and insulation fittings. The body and the air gap are parallel to both ends of the insulator. When lightning strikes, the internal short gap of the main body and the air gap break down, and the lightning arc enters the arc-extinguishing body through the breakdown channel. In the structure, the arc is compressed by force to form internal and external gradients of temperature and to produce jet airflow. The jet airflow acts on the subsequent power frequency follow current arc, which is suppressed and extinguished. In this paper, a model coupling an arc and a compressed jet airflow in a multi-fracture compression airflow arc-extinguishing structure is established theoretically and simulated by simulation software. Finally, a power frequency follow current interruption test is carried out. The simulation results show that a high-speed airflow of 600 m/s is formed around the fracture at approximately 0.99 ms, and the airflow is proportional to the rate of temperature variation. The test results show that the power frequency follow current of 1.289 kA is cut off within approximately 3 ms without a reburning phenomenon. The effect of power frequency follow current interruption is obvious in the structure.
Integrating a pharmacist into the perioperative setting
Authors: Forrester Tori G. , Sullivan Sara , Snoswell Centaine L. , Pillans Peter , Barras Michael , Sturgess David
Published: March 2020

This paper describes the integration of a pharmacist into a perioperative environment and the ensuing quality and economic benefits. Deficiencies were identified in medication management in operating theatres (OT) at a large tertiary hospital. A perioperative pharmacist was employed for a 6-month pilot period, with permanent funding dependent on demonstration of agreed economic benefits. A multidisciplinary committee set goals, drove strategic initiatives and was accountable for delivery of outcomes. Pharmaceutical expenditure was analysed and high expenditure items targeted. Cost savings and staff satisfaction were measured at 6 months. Savings of A$63 884 were achieved during the pilot period, resulting from optimised pharmaceutical unit pricing, OT medication stock on hand (imprest) review and redesigned medication management strategies. Improvements in medication management included better access to medications in the OT, rationalising available products to minimise wastage and implementation of guidelines and protocols for high-cost and high-risk medications. At 6 months, 97% of theatre staff supported continuation of the role; the project was extended with demonstrated cost savings of A$157 265 at 12 months. The integration of a perioperative pharmacist resulted in cost savings and medication management improvements in the OT setting. A permanent position was funded. What is known about the topic? Medication use in OTs involves high volumes of high-risk and high-cost medications. Historically, there has been little pharmacist involvement in OTs, even though evidence has shown that hospital pharmacists can reduce medication errors, improve patient safety and reduce costs. What does this paper add? This paper provides an overview of the process of establishing a perioperative pharmacist role in an adult tertiary hospital. It takes readers through the journey from pre-implementation audit to trial development, stakeholder consultation and specific medication and process targets. What are the implications for practitioners? Hospitals and practitioners are faced with the challenge of improving service delivery within the constraints of a finite budget. This paper allows readers to learn from our experience and apply these learnings to their local hospital setting, ultimately improving both patient care and staff satisfaction through the development of a perioperative pharmacist service.
O-GlcNAcylation regulates the methionine cycle to promote pluripotency of stem cells
Authors: Zhu Qiang , Cheng Xuejun , Cheng Yaxian , Chen Junchen , Xu Huan , Gao Yuntao , Duan Xiaotao , Ji Junfeng , Li Xuekun , Yi Wen
Published: March 2020

Methionine metabolism is critical for the maintenance of embryonic stem cells (ESCs) and induced pluripotent stem cells (iPSCs) pluripotency. However, little is known about the regulation of the methionine cycle to sustain ESC pluripotency. Here, we show that adenosylhomocysteinase (AHCY), an important enzyme in the methionine cycle, is critical for the maintenance and differentiation of mouse embryonic stem cells (mESCs). We show that mESCs exhibit high levels of methionine metabolism, whereas decreasing methionine metabolism via depletion of AHCY promotes mESCs to differentiate into the three germ layers. AHCY is posttranslationally modified with an O-linked β-
N
-acetylglucosamine sugar (O-GlcNAcylation), which is rapidly removed upon differentiation. O-GlcNAcylation of threonine 136 on AHCY increases its activity and is important for the maintenance of trimethylation of histone H3 lysine 4 (H3K4me3) to sustain mESC pluripotency. Blocking glycosylation of AHCY decreases the ratio of S-adenosylmethionine versus S-adenosylhomocysteine (SAM/SAH), reduces the level of H3K4me3, and poises mESC for differentiation. In addition, blocking glycosylation of AHCY reduces somatic cell reprogramming. Thus, our findings reveal a critical role of AHCY and a mechanistic understanding of O-glycosylation in regulating ESC pluripotency and differentiation.
A cullin-RING ubiquitin ligase promotes thermotolerance as part of the intracellular pathogen response in
Caenorhabditis elegans
Authors: Panek Johan , Gang Spencer S. , Reddy Kirthi C. , Luallen Robert J. , Fulzele Amitkumar , Bennett Eric J. , Troemel Emily R.
Published: March 2020

Intracellular pathogen infection leads to proteotoxic stress in host organisms. Previously we described a physiological program in the nematode
Caenorhabditis elegans
called the intracellular pathogen response (IPR), which promotes resistance to proteotoxic stress and appears to be distinct from canonical proteostasis pathways. The IPR is controlled by PALS-22 and PALS-25, proteins of unknown biochemical function, which regulate expression of genes induced by natural intracellular pathogens. We previously showed that PALS-22 and PALS-25 regulate the mRNA expression of the predicted ubiquitin ligase component cullin
cul-6
, which promotes thermotolerance in
pals-22
mutants. However, it was unclear whether CUL-6 acted alone, or together with other cullin-ring ubiquitin ligase components, which comprise a greatly expanded gene family in
C. elegans
. Here we use coimmunoprecipitation studies paired with genetic analysis to define the cullin-RING ligase components that act together with CUL-6 to promote thermotolerance. First, we identify a previously uncharacterized RING domain protein in the TRIM family we named RCS-1, which acts as a core component with CUL-6 to promote thermotolerance. Next, we show that the Skp-related proteins SKR-3, SKR-4, and SKR-5 act redundantly to promote thermotolerance with CUL-6. Finally, we screened F-box proteins that coimmunoprecipitate with CUL-6 and find that FBXA-158 and FBXA-75 promote thermotolerance. In summary, we have defined the three core components and two F-box adaptors of a cullin-RING ligase complex that promotes thermotolerance as part of the IPR in
C. elegans
, which adds to our understanding of how organisms cope with proteotoxic stress.
Design as externalization
Authors: Davis Stephen Boyd , Vane Olivia
Published: March 2020

The article is concerned with a central contribution of designing to information visualization in the digital humanities. The activity is characterized as one of externalization, instantiation in visible or tangible form of ideas. A spectrum of different interpretations of this process in the existing literature is discussed. The arguments are illustrated with recent practical examples from the authors’ own work in designing with a range of cultural organizations. The article concludes with reflections on how projects may best benefit from this work of design, empowering the designer as a co-researcher, alongside the historian, curator or other humanities scholar.
Designing bowel preparation patient instructions to improve colon cancer detection
Authors: Noël Guillermina , Frascara Jorge , Wong Clarence
Published: March 2020

Medical personnel usually write and design documents that inform physicians or patients about procedures or therapies. Document design, however, requires skills that are not normally applied, resulting in information that is often not used properly. This article describes a project developed by the Alberta Colorectal Cancer Screening Program. The goal was to help patients better prepare for their colonoscopies. The process started with an analysis of the existing documents, and the development of performance specifications based on the literature on legibility, reading comprehension, memorization and use of information, plain language, visual perception, page layout, and image use. The project included an iterative process of prototyping and testing that resulted in 23 design criteria. Each iteration was tested with users to ensure ease of use, completeness of information, and accuracy and clarity to facilitate adoption. The project helped reduce practice variation regarding bowel preparation in the province of Alberta, Canada. This project illustrates how information design can help healthcare organizations provide patient-centred care. Information design helps patients engage in their own caring process, by providing information that people can use, understand and apply. After 15 months of use, the document has been downloaded more than 48,000 times, suggesting a good physician reception.
Repeated readings and Chinese immersion students’ reading fluency, comprehension and character
recognition
Authors: Knell Ellen , Fame Kao Shin Chi
Published: March 2020

Although reading fluency instruction has been identified as an important literacy focus for English proficient
students, little research has examined its role in foreign language settings, and it has not been studied in Chinese immersion
education. The current research compared two seventh grade Chinese immersion classes. One class did repeated timed readings in
student pairs, while the other class spent more time on comprehension activities. Both groups increased their correct Chinese
characters per minute rates over the treatment period, but the repeated readings group outperformed the other group on reading
fluency, character recognition, and reading comprehension measures. In addition, the students who engaged in repeated readings
were better able to generalize reading fluency gains to new, but related, reading materials; they also reported more confidence
and enjoyment when reading Chinese. Suggestions for integrating peer reading fluency procedures into language arts instruction are
proposed.
From burden to threat
Authors: Brookes Gavin , Wright David
Published: March 2020

This chapter focuses on the ways in which non-native English
speakers living in Britain are represented in the British press, and in particular on
how these representations have changed between 2005 and 2017. Using a corpus-assisted
approach to Critical Discourse Analysis, collocation patterns of the phrase
speak English reveal that migrants are represented in different ways
across the 13-year period, which sees the levels of blame, threat and exclusion levelled
at migrants increase and change shape over the years. This chapter builds on previous
work by the authors, and emphasizes the importance of re-visiting and adding to corpora
when analyzing dynamic discourses, and identifies two different ways in which change can
manifest in collocation analysis: through the identification of occasional ‘seasonal’
collocates, and via consistent collocates being part of different representational
patterns.
Two sides of the same coin?
Authors: Blanco-Suárez Zeltia
Published: March 2020

This chapter presents a corpus-based study on the origin and
development of two death-related intensifiers: the adjectives and adverbs
deadly and mortal. The historical sources consulted
reveal that these forms have progressively adopted more general meanings, that is, they
have come to be grammaticalized as intensifiers over time. Two semantic variables, type
of meaning (descriptive, affective, or intensifying, along the lines of Adamson 2000) and semantic prosody (Stubbs 1995), were central to the collocational
diachronic analysis undertaken here. The study focuses on British English and covers the
history of deadly and mortal from their origins in Old
English and Middle English, respectively, to the 20th century.
Changes in transitivity and reflexive uses of sit
(me/myself down) in Early and Late Modern
English
Authors: Vartiainen Turo , Höglund Mikko
Published: March 2020

This chapter seeks to establish if the Transitivity Hypothesis
(Hopper & Thompson 1980) can explain
the variation in the use of two reflexive strategies with the verb sit
in Early Modern English (e.g. I sat me down/I sat myself down) and the
verb’s subsequent transitivization (e.g. he sat me down). By studying
data from large historical corpora, we will re-evaluate the results of earlier research
and establish why sit continued to be used with the simple reflexive
strategy (i.e. with object pronouns) until the Late Modern period. In our analysis of
the transitivization of sit (down), we focus on both micro-level
semantic and syntactic factors and more general developments that have supported the
transitivization of verbs in Late Modern English.
The Linguistics of Name Translation: Preferred Personal and Business Names in English, Korean, and Chinese
Authors: Kim Jong-mi
Published: March 2020

This research examines personal and business names and their translations among typologically contrastive languages: English, Korean, and Chinese. A linguistic framework is proposed that predicts and tests whether and how ideal translations will be based on sound or meaning, as defined by the phonetic or semantic features of the given orthography. Two separate surveys (online in the US and onsite in Korea) were taken about preferred translations of names from and to the three languages. The linguistic prediction was borne out by the survey results: sound translation is preferred from and to English, meaning translation from and to Chinese, and preference is mixed from and to Korean. An additional finding was that translation preference was sound-based for personal names but meaning-based for business names. The full list of 118 original names and 302 translation choices in the three languages investigated in this study is provided in the appendix.
Persistent current formation in double-ring geometries
Authors: Bland T , Marolleau Q , Comaron P , Malomed B A , Proukakis N P
Published: March 2020

Quenching an ultracold bosonic gas in a ring across the Bose–Einstein condensation phase transition is known, and has been experimentally observed, to lead to the spontaneous emergence of persistent currents. The present work examines how these phenomena generalize to a system of two experimentally accessible explicitly two-dimensional co-planar rings with a common interface, or to the related lemniscate geometry, and demonstrates an emerging independence of winding numbers across the rings, which can exhibit flow both in the same and in opposite directions. The observed persistence of such findings in the presence of dissipative coupled evolution due to the local character of the domain formation across the phase transition and topological protection of the randomly emerging winding numbers should be within current experimental reach.
Biharmonic wave maps: local wellposedness in high regularity
Authors: Herr Sebastian , Lamm Tobias , Schmid Tobias , Schnaubelt Roland
Published: March 2020

We show the local wellposedness of biharmonic wave maps with initial data of sufficiently high Sobolev regularity and a blow-up criterion in the sup-norm of the gradient of the solutions. In contrast to the wave maps equation we use a vanishing viscosity argument and an appropriate parabolic regularization in order to obtain the existence result. The geometric nature of the equation is exploited to prove convergence of approximate solutions, uniqueness of the limit, and continuous dependence on initial data.
Reactive dynamics and spectroscopy of hydrogen transfer from neural network-based reactive potential energy surfaces
Authors: Käser Silvan , Unke Oliver T , Meuwly Markus
Published: March 2020

The ‘in silico’ exploration of chemical, physical and biological systems requires accurate and efficient energy functions to follow their nuclear dynamics at a molecular and atomistic level. Recently, machine learning tools have gained a lot of attention in the field of molecular sciences and simulations and are increasingly used to investigate the dynamics of such systems. Among the various approaches, artificial neural networks (NNs) are one promising tool to learn a representation of potential energy surfaces. This is done by formulating the problem as a mapping from a set of atomic positions x and nuclear charges Z

i
to a potential energy V(x). Here, a fully-dimensional, reactive neural network representation for malonaldehyde (MA), acetoacetaldehyde (AAA) and acetylacetone (AcAc) is learned. It is used to run finite-temperature molecular dynamics simulations, and to determine the infrared spectra and the hydrogen transfer rates for the three molecules. The finite-temperature infrared spectrum for MA based on the NN learned on MP2 reference data provides a realistic representation of the low-frequency modes and the H-transfer band whereas the CH vibrations are somewhat too high in frequency. For AAA it is demonstrated that the IR spectroscopy is sensitive to the position of the transferring hydrogen at either the OCH- or OCCH3 end of the molecule. For the hydrogen transfer rates it is demonstrated that the O–O vibration (at ∼250 cm−1) is a gating mode and largely determines the rate at which the hydrogen is transferred between the donor and acceptor. Finally, possibilities to further improve such NN-based potential energy surfaces are explored. They include the transferability of an NN-learned energy function across chemical species (here methylation) and transfer learning from a lower level of reference data (MP2) to a higher level of theory (pair natural orbital-LCCSD(T)).
Scale-invariant spin dynamics and the quantum limits of field sensing
Authors: Mitchell Morgan W
Published: March 2020

We describe quantum limits to field sensing that relate noise, geometry and measurement duration to fundamental constants, with no reference to particle number. We cast the Tesche and Clarke (TC) bound on dc-SQUID sensitivity as such a limit, and find analogous limits for volumetric spin-precession magnetometers. We describe how randomly-arrayed spins, coupled to an external magnetic field of interest and to each other by the magnetic dipole–dipole interaction, execute a spin dynamics that depolarizes the spin ensemble even in the absence of coupling to an external reservoir. We show the resulting spin dynamics are scale invariant, with a depolarization rate proportional to spin number density and thus a number-independent quantum limit on the energy resolution per bandwidth E
R. Numerically, we find E
R ⩾ αℏ, α ∼ 1, in agreement with the TC limit, for paradigmatic spin-based measurements of static and oscillating magnetic fields.
Towards all-optical atom chips based on optical waveguides
Authors: Ovchinnikov Yuri B , Ayi-Yovo Folly Eli
Published: March 2020

Coherent guiding of atoms in two-colour evanescent light fields of two fundamental modes of suspended optical rib waveguides is investigated theoretically. Special attention is paid to waveguides of widths larger than the wavelength of light, which provide better lateral stability of the surface traps and waveguides, and can be used in coherent Bragg beam splitters for matter waves, based on optical gratings formed by interference of evanescent light waves of two crossed optical waveguides. A single-mode regime for evanescent-wave waveguides for atoms is investigated. The general structure and key elements of all-optical atom chips are discussed.
Epitaxial graphene gas sensors on SiC substrate with high sensitivity
Authors: Yu Cui , Liu Qingbin , He Zezhao , Gao Xuedong , Wu Enxiu , Guo Jianchao , Zhou Chuangjie , Feng Zhihong
Published: March 2020

2D material of graphene has inspired huge interest in fabricating of solid state gas sensors. In this work, epitaxial graphene, quasi-free-standing graphene, and CVD epitaxial graphene samples on SiC substrates are used to fabricate gas sensors. Defects are introduced into graphene using SF6 plasma treatment to improve the performance of the gas sensors. The epitaxial graphene shows high sensitivity to NO2 with response of 105.1% to 4 ppm NO2 and detection limit of 1 ppb. The higher sensitivity of epitaxial graphene compared to quasi-free-standing graphene, and CVD epitaxial graphene was found to be related to the different doping types of the samples.
High wall-plug efficiency 808-nm laser diodes with a power up to 30.1 W
Authors: Ren Zhanqiang , Li Qingmin , Li Bo , Song Kechang
Published: March 2020

A very highly efficient InGaAlAs/AlGaAs quantum-well structure was designed for 808 nm emission, and laser diode chips 390-μm-wide aperture and 2-mm-long cavity length were fabricated. Special pretreatment and passivation for the chip facets were performed to achieve improved reliability performance. The laser chips were p-side-down mounted on the AlN sub-mount, and then tested at continuous wave (CW) operation with the heat-sink temperature setting to 25 °C using a thermoelectric cooler (TEC). As high as 60.5% of the wall-plug efficiency (WPE) was achieved at the injection current of 11 A. The maximum output power of 30.1 W was obtained at 29.5 A when the TEC temperature was set to 12 °C. Accelerated life-time test showed that the laser diodes had lifetimes of over 62 111 h operating at rated power of 10 W.
Effect of thermorheological properties on tribological behaviors of lubricating grease
Authors: Jiabao Pan , Guangxin Yang , Jianping Wang
Published: March 2020

Lubricating grease has increased thermorheological properties during heating, which may affect the lubrication of the friction pair. And a friction pair usually heats up in the working process. This study explored the effect of surface temperature of the friction pair on the lubrication performance under lubrication conditions. The thermorheological properties of lubricating grease were analyzed using a rotational rheometer, and the variations and mechanisms of the thermo- rheological properties were explored. The friction-wear test on lubrication was conducted at different temperatures to examine the effects of thermorheological properties on the tribological behaviors of lubricating grease. Wear scar morphology, composition change, and friction-lubrication mechanisms at different temperatures were probed through SEM and X-ray spectrometer analysis. The results showed that lubricating grease has significant thermorheological properties. Moreover, its soap fiber entanglement decreases with rising temperature, and the entanglement properties are slowly lost at high temperature. The soap fiber structure of lubricating grease plays a vital role in lubrication. As temperature rises, the soap fiber entanglement of lubricating grease decreases and the base oil is more easily released under shear, exhibiting a trend of friction coefficient decreasing with the rising temperature. High temperatures weaken the soap fiber entanglement of lubricating grease, the film-forming property, and the surface friction-abrasion resistance of the friction pair and even cause oxidative wear.
Non-conserving zero-range processes with extensive rates under resetting
Authors: Grange Pascal
Published: March 2020

We consider a non-conserving zero-range process with hopping rate proportional to the number of particles at each site. Particles are added to the system with a site-dependent creation rate, and vanish with a uniform annihilation rate. On a fully-connected lattice with a large number of sites, the mean-field geometry leads to a negative binomial law for the number of particles at each site, with parameters depending on the hopping, creation and annihilation rates. This model can be mapped to population dynamics (if the creation rates are reproductive fitnesses in a haploid population, and the hopping rate is the mutation rate). It can also be mapped to a Bianconi–Barabási model of a growing network with random rewiring of links (if creation rates are the rates of acquisition of links by nodes, and the hopping rate is the rewiring rate). The steady state has recently been worked out and gives rise to occupation numbers that reproduce Kingman’s house-of-cards model of selection and mutation. In this paper we solve the master equation using a functional method, which yields integral equations satisfied by the occupation numbers. The occupation numbers are shown to forget initial conditions at an exponential rate that decreases linearly with the fitness level. Moreover, they can be computed exactly in the Laplace domain, which allows to obtain the steady state of the system under resetting. The result modifies the house-of-cards result by simply adding a skewed version of the initial conditions, and by adding the resetting rate to the hopping rate.
Objective identification of potentially damaging tropical cyclones over the Western North Pacific
Authors: Befort D J , Kruschke T , Leckebusch G C
Published: March 2020

An impact-oriented objective windstorm identification algorithm (WiTRACK), originally developed and well established for studies on extra-tropical storms, is further developed to identify damage and loss related Tropical Cyclones (TC) over the Western North Pacific. Results based on JRA-55 reanalysis data reveal that WiTRACK is able to detect the majority of strong events with hitrates of about 77%/90%/98% for TCs of the three most severe categories. Using economic loss data for China, it is found that especially events with large losses are associated with a windstorm event identified by WiTRACK. Past loss events successfully tracked by WiTRACK are associated with substantially higher losses than those events, not identified by WiTRACK. Thus, even though less skilful than traditional detection schemes if evaluated for the totality of TC events, WiTRACK is a powerful tool to identify severe, damage and loss-related TC events which additionally benefits from its simplicity and minimal input data demands. The latter may allow to apply WiTRACK to datasets not meeting the data requirements of more complex TC detection schemes.
Large area few-layer TMD film growths and their applications
Authors: Mandyam Srinivas V , Kim Hyong M , Drndić Marija
Published: March 2020

Research on 2D materials is one of the core themes of modern condensed matter physics. Prompted by the experimental isolation of graphene, much attention has been given to the unique optical, electronic, and structural properties of these materials. In the past few years, semiconducting transition metal dichalcogenides (TMDs) have attracted increasing interest due to properties such as direct band gaps and intrinsically broken inversion symmetry. Practical utilization of these properties demands large-area synthesis. While films of graphene have been by now synthesized on the order of square meters, analogous achievements are difficult for TMDs given the complexity of their growth kinetics. This article provides an overview of methods used to synthesize films of mono- and few-layer TMDs, comparing spatial and time scales for the different growth strategies. A special emphasis is placed on the unique applications enabled by such large-scale realization, in fields such as electronics and optics.
Effect of NOCOLOK® flux dry-off temperature on mechanical properties of brazed joint for automotive aluminum-based heat exchangers
Authors: Hashemi Milani Seyyed Ali Akbar , Tavangar Reza , Azadbeh Maziyar
Published: March 2020

The drying temperature of the flux at a normal atmosphere has a crucial role in brazing quality in automotive aluminum-based heat exchangers. Throughout this research, NOCOLOK® flux consists of two phases of K2AlF5.H2O and KAlF4 with a melting point around 580 °C was used. A flux slurry was applied on the base metal and dried at 220, 300 and 380 °C in air. The mechanical assessment revealed that when flux dried at 300 °C, the joint withstand maximum shear stress of 44 MPa with complete bonding. At 220 °C and 380 °C, joint shear stresses are 34 MPa, 30 MPa respectively. 380 °C dry-off temperature under nitrogen gas improved shear strength to 39 MPa. Taking dry-off temperature as 300 °C the number of defective heat exchangers was reduced from 3.2% to 0.6% every week.
Koszul duality for Iwasawa algebras modulo 𝑝
Authors: Sorensen Claus
Published: March 2020

In this article we establish a version of Koszul duality for filtered rings arising from

p
p

-adic Lie groups. Our precise setup is the following. We let

G
G

be a uniform pro-

p
p

group and consider its completed group algebra

\Omega =k\lBrack G\rBrack with coefficients in a finite field

k
k

of characteristic

p
p

. It is known that

Ω
\Omega

carries a natural filtration and

gr
Ω
=
S
(

g

)

\text {gr} \Omega =S(\frak {g})

where

g

\frak {g}

is the (abelian) Lie algebra of

G
G

over

k
k

. One of our main results in this paper is that the Koszul dual

gr

Ω
!

=
⋀

g

∨

\text {gr} \Omega ^!=\bigwedge \frak {g}^{\vee }

can be promoted to an

A

∞

A_{\infty }

-algebra in such a way that the derived category of pseudocompact

Ω
\Omega

-modules

D
(
Ω
)

D(\Omega )

becomes equivalent to the derived category of strictly unital

A

∞

A_{\infty }

-modules

D

∞

(
⋀

g

∨

)

D_{\infty }(\bigwedge \frak {g}^{\vee })

. In the case where

G
G

is an abelian group we prove that the

A

∞

A_{\infty }

-structure is trivial and deduce an equivalence between

D
(
Ω
)

D(\Omega )

and the derived category of differential graded modules over

⋀

g

∨

\bigwedge \frak {g}^{\vee }

which generalizes a result of Schneider for

Z

p

\Bbb {Z}_p

.
Occupational Exposure and Ventilation Assessment in New York City Nail Salons
Authors: Harrichandra Amelia , Roelofs Cora , Pavilonis Brian
Published: March 2020

In 2015, New York State enacted new ventilation regulations to protect employees and clients from exposure to chemicals used in nail salons. This study measured common air pollutants found in nail salons and assessed compliance with ventilation requirements. Area sampling was conducted in 12 nail salons located in New York City for three consecutive days (Thursday, Friday, and Saturday) to measure total volatile organic compounds (TVOCs), methyl methacrylate, toluene, and ethyl acetate concentrations and estimate ventilation rates. Salon characteristics were determined through a walkthrough inspection and survey administered to the manager. The average daily concentration of carbon dioxide and TVOCs across all salons was 1070 ppm [standard deviation (SD) = 440 ppm] and 29 ppm (SD = 25 ppm), respectively. Chemical-specific air sampling showed low to non-detectable levels of the three measured chemicals. Seventy-five percent of the nail salons did not meet general minimum outdoor airflow requirements. Little temporal variation was observed in day-to-day average concentrations of contaminants within salons, indicating uniform exposure during high customer count days. Salons that met the outdoor airflow requirements had twice the average daily customers (83 versus 42) and half the TVOC concentrations compared with salons that did not (33 versus 16 ppm). Nail salons not meeting ventilation requirements tended to have fewer customers and managers that did not understand the essential components of the ventilation system. Data from this study can be used as evidence of reduction in exposure due to compliance with the ventilation requirements.
Mortality Among Firefighters in Spain: 10 Years of Follow-up
Authors: Zhao Guanlan , Erazo Boris , Ronda Elena , Brocal Francisco , Regidor Enrique
Published: March 2020

Objectives

The objective of this study was to compare mortality rates for the main causes of death and the most frequent sites of cancer in firefighters and all other occupations.

Methods

Mortality was calculated from a longitudinal study conducted between 2001 and 2011 following a total of 9.5 million men aged 20–64 years old who were in employment in 2001. The age-standardized mortality rate for firefighters was calculated for cancer and other causes of death and compared with that for all other occupations using the mortality rate ratio (MRR).

Results

No differences were observed between firefighters and all other occupations for overall mortality [MRR = 0.99, 95% confidence interval (CI): 0.91–1.07] or for mortality from cancer in general (MRR = 1.00, 95% CI: 0.89–1.12). No significant differences were observed in mortality by site of cancer, except for mortality from cancer of larynx (MRR = 1.77, 95% CI: 1.01–3.09) and hypopharynx (MRR = 2.96, 95% CI: 1.31–6.69), which presented a higher magnitude in firefighters. Neither was any significant differences observed between the two groups in mortality due to cardiovascular, respiratory, or digestive diseases or in mortality due to external causes.

Conclusions

Exposure to carcinogens combined with a possible failure to use respiratory protection when fighting fires may be responsible for excess mortality from laryngeal and hypopharyngeal cancer in firefighters. In the future, more research is needed on the health of firefighters and strengthening preventive policies for these workers.
Comparison of the mitochondrial phylogeographical structure of a generalist and two specialist frog species reveals contrasting patterns in the Eastern and Western Cape provinces of South Africa
Authors: Kushata Judith N T , Conradie Werner , Cherry Michael I , Daniels Savel R
Published: March 2020

In this study, we examined the phylogeographical structure of three frog species (Anhydrophryne rattrayi, Arthroleptis wageri and Cacosternum nanum) in the Eastern and Western Cape provinces of South Africa. The first two species are forest dwelling and exhibit direct development, whereas the last species is a habitat generalist, breeding in open freshwater bodies and exhibiting rapid metamorphosis. Evolutionary relationships were inferred using combined mitochondrial DNA (mtDNA) sequence data [16S rRNA and cytochrome b (Cytb)]. Divergence times were estimated for each species using the combined mtDNA dataset, and population genetic structuring was inferred using haplotype networks and analysis of molecular variance using the rapidly evolving Cytb locus. The two forest-dwelling species (Anhydrophryne rattrayi and Arthroleptis wageri) each revealed two statistically well-supported clades and were characterized by marked genetic differentiation and the general absence of shared maternal haplotypes, indicating no maternal gene flow between conspecific populations; a result corroborated by moderate values of pairwise genetic distance. In contrast, for the generalist species C. nanum, two shallow clades were observed and several haplotypes were shared between localities, indicating moderate maternal gene flow. Diversification in the two forest-dwelling species occurred during the Plio-Pleistocene climatic oscillations and was associated with increased xeric conditions, whereas in C. nanum a recent, Holocene divergence was inferred. Ancient climatic factors thought to be causal in the divergences within each of the three species are discussed. The marked mtDNA differentiation in the two forest specialist species suggests the presence of distinct management units that should be considered in future conservation management decisions.
Beyond forests in the Amazon: biogeography and floristic relationships of the Amazonian savannas
Authors: Devecchi Marcelo F , Lovo Juliana , Moro Marcelo F , Andrino Caroline O , Barbosa-Silva Rafael G , Viana Pedro L , Giulietti Ana Maria , Antar Guilherme , Watanabe Maurício T C , Zappi Daniela C
Published: March 2020

Open habitats such as grasslands occupy < 5% of the Amazon and are currently grouped under the broad term Amazonian savanna, covering an area of c. 267 000 km2, mostly in Brazil and Bolivia. These habitats are found isolated within an extensive rainforest matrix, having a distinct flora from the latter. The lower Amazon River is home to several patches of savanna that occupy both south and north banks of the river, in Santarém, Alenquer and Monte Alegre. Although having an abundance of herbaceous plants, most studies on these open areas focus only on tree species, ignoring the relevant non-woody component of the vegetation. Our objectives were to provide new surveys of seed plants for two Amazonian savanna sites and to take the opportunity to revisit the biogeographical links between Amazonian savanna, Amazonian canga vegetation and the central Brazilian cerrado (CBC) and caatinga, analysing woody and herbaceous plants. We created a floristic database that includes sites of Amazonian savannas, including campinarana, coastal scrub (restinga), CBC and Amazonian campos rupestres (on canga or other substrate). We compared those sites using multivariate analyses to find out the degree of floristic resemblance between sites. We prepared a new list of 406 species of seed plants [336 in Parque Estadual de Monte Alegre (PEMA) and 117 in Serra do Itauajuri (SI)], including 23 new records for the state of Pará and some putative new species for science. The Amazonian savannas form three loosely arranged groups, whereas the Amazonian canga formed a cohesive assemblage. Both groups were contrasted against cerrado and caatinga sites and had a distinctive flora from both. Sites from north-western Pará (Alter do Chão, PEMA and SI) were grouped with their northern counterparts in Roraima. An improved representation of the flora of these sites is provided, with more insight into the relationship between the Amazonian savanna sites and other vegetation types. It is worrying that recent changes of the Brazilian legislation place open environments, such as PEMA, in the path of vulnerability to disturbance and destruction.
COVID-19 Transmission Within a Family Cluster by Presymptomatic Carriers in China
Authors: Qian Guoqing , Yang Naibin , Ma Ada Hoi Yan , Wang Liping , Li Guoxiang , Chen Xueqin , Chen Xiaomin
Published: March 2020

We report a family cluster of coronavirus disease 2019 (COVID-19) caused by a presymptomatic case. There were 9 family members, including 8 laboratory-confirmed with COVID-19, and a 6-year-old child had no evidence of infection. Among the 8 patients, 1 adult and a 13-month-old infant were asymptomatic, and 1 adult was diagnosed as having severe pneumonia.
The Treaty as to Commercial Relations of 1903: China and Extraterritoriality
Authors: Soffe Raphaëlle P
Published: March 2020

The history of United States and Chinese intellectual property relations formally began with the signing of the Treaty as to Commercial Relations in 1903. The next three years saw the Chinese government frequently present revised versions of the 1903 Treaty’s implementation terms, with the 1905 Shangpu Draft responding to foreign merchant requests by removing its commitment to extraterritoriality—a regime whereby Western citizens in China were subject solely to the laws of their own country and not to Chinese laws. In this article, I document the intellectual property violations by Americans and Europeans in China, and how the legal case made by China for the removal of extraterritoriality, specifically for intellectual property violations, was a sign in itself that China was increasingly attentive to the mechanisms and constraints involved in legal reform. The collapse of the negotiations in 1906 would serve as a critical juncture in the commitment and interest of China to pursue intellectual property reform, with the US and China not signing another treaty concerning copyright until 1946. The refusal by the US to compromise on extraterritoriality contributed, in part, to the ‘four decades of inaction’ in intellectual property affairs.
Effect of altitude on mortality of end-stage renal disease patients on hemodialysis in Peru
Authors: Bravo-Jaimes Katia , Loescher Viky Y , Canelo-Aybar Carlos , Rojas-Camayo Jose , Mejia Christian R , Schult Sandra , Nieto Ruben , Singh Kyra , Messing Susan , Hinostroza Juana
Published: March 2020

Background

In Latin America, the prevalence of end-stage kidney disease (ESKD) has risen tremendously during the last decade. Previous studies have suggested that receiving dialysis at high altitude confers mortality benefits; however, this effect has not been demonstrated at >2000 m above sea level (masl) or in developing countries.

Methods

This historical cohort study analyzed medical records from six Peruvian hemodialysis (HD) centers located at altitudes ranging from 44 to 3827 masl. Adult ESKD patients who started maintenance HD between 2000 and 2010 were included. Patients were classified into two strata based on the elevation above sea level of their city of residence: low altitude (<2000 masl) and high altitude (≥2000 masl). Death from any cause was collected from national registries and Cox proportional hazards models were built.

Results

A total of 720 patients were enrolled and 163 (22.6%) resided at high altitude. The low-altitude group was significantly younger, more likely to have diabetes or glomerulonephritis as the cause of ESKD and higher hemoglobin. The all-cause mortality rate was 84.3 per 1000 person-years. In the unadjusted Cox model, no mortality difference was found between the high- and low-altitude groups {hazard ratio [HR] 1.20 [95% confidence interval (CI) 0.89–1.62]}. After multivariable adjustment, receiving HD at high altitude was not significantly associated with higher mortality, but those with diabetes as the cause of ESKD had significantly higher mortality [HR 2.50 (95% CI 1.36–4.59)].

Conclusions

In Peru, patients receiving HD at high altitudes do not have mortality benefits.
Larval density affects phenotype and surrounding bacterial community without altering gut microbiota in Drosophila melanogaster
Authors: Henry Y , Tarapacki P , Colinet H
Published: March 2020

Larval crowding represents a complex stressful situation arising from inter-individual competition for time- and space-limited resources. The foraging of a large number of individuals may alter the chemical and bacterial composition of food and in turn affect individual's traits. Here we used Drosophila melanogaster to explore these assumptions. First, we used a wide larval density gradient to investigate the impact of crowding on phenotypical traits. We confirmed that high densities increased development time and pupation height, and decreased viability and body mass. Next, we measured concentrations of common metabolic wastes (ammonia, uric acid) and characterized bacterial communities, both in food and in larvae, for three contrasting larval densities (low, medium and high). Ammonia concentration increased in food from medium and high larval densities, but remained low in larvae regardless of the larval density. Uric acid did not accumulate in food but was detected in larvae. Surprisingly, bacterial composition remained stable in guts of larvae whatever their rearing density, although it drastically changed in the food. Overall, these results indicate that crowding deeply affects individuals, and also their abiotic and biotic surroundings. Environmental bacterial communities likely adapt to altered nutritional situations resulting from crowding, putatively acting as scavengers of larval metabolic wastes.