bluuebunny/crossref_metadata_2025 huggingface dataset:
Spatial‐temporal response capability probabilistic evaluation method of electric vehicle aggregator based on trip characteristics modelling
Authors: Xu Xiangchu , Mi Zengqiang , Yu Shiyuan , Zhan Zewei , Ji Ling
Published: February 2023

Accurately evaluating the response capability of electric vehicles (EVs) is very important for an EV aggregator (EVA) to formulate reasonable bidding strategies in ancillary service markets. Most of the methods proposed in the existing literature only evaluate EVs’ temporal response capability while ignoring their spatial distribution. In addition, the evaluation results provided by the existing methods are typically deterministic, which fails to characterize the uncertainty of EV trip. The above two issues pose high risk of economic loss for the EVA. To this end, a probabilistic evaluation method of spatial‐temporal response capability for EVA is proposed in this paper. The gravity model is adopted to calculate a spatial transfer probability matrix describing EV owners’ trip characteristics between different areas at each time in a region which is divided into several different areas according to the evaluation requirements. Then, the trip chains of EVs are modelled based on the spatial transfer probability matrix, and the states of charge (SOCs) of EVs are tracked in the process. The spatial‐temporal response capability of EVA is evaluated based on charging–discharging states and states of charge of EVs, and the probabilistic evaluation results of response capability are obtained by multiple Monte Carlo simulations. The effectiveness of the proposed method is verified on a real dataset from San Francisco, CA, USA.
CO(2−1) survey at 9 pc resolution in the Small Magellanic Cloud
Authors: Saldaño H. P. , Rubio M. , Bolatto A. D. , Verdugo C. , Jameson K. E. , Leroy A. K.
Published: February 2023

Context. The Small Magellanic Cloud (SMC) is the closest low-metallicity galaxy to the Milky Way where the dynamical state of molecular clouds can be analyzed.

Aims. Our aim is to present a CO(2−1) survey at ~9 pc resolution obtained with the Atacama Pathfinder Experiment telescope in an extensive region (~0.4kpc2) of the SMC and uniformly characterize the properties of the SMC clouds.

Methods. We used the CPROPS algorithm to identify the molecular clouds and estimate their main CO properties. We analyzed the characteristics of the SMC clouds by studying the scaling relations between the radii, velocity dispersions, luminosities, and virial masses. We also analyzed the mass spectrum of the SMC through the cumulative mass distribution. We used the dust-based total gas masses of SMC clouds presented in the literature to analyze the stability of the molecular clouds and also to estimate the CO-to-H2 conversion factor for the SMC. We used young stellar objects (YSOs) and HII region catalogs in the literature and IR observations in public databases to inspect the star-forming regions in the SMC.

Results. We identified 177 molecular clouds within the SMC, of which 124 clouds are fully resolved with signal-to-noise ratios ≳5. We found that the CO luminosity of the identified clouds is (1.3 ± 0.2) × 105 K kms−1 pc2 (representing at least 70% of the total CO luminosity of the region) and the corresponding gas mass from virial determination is Mgas = (1.5 ± 0.5) × 106 M⊙. The scaling relationships show that the SMC clouds are (on average) less turbulent and less luminous than their inner Milky Way counterparts of similar size by a factor of approximately two and three, respectively, while for a fixed linewidth, the SMC clouds are overluminous by a factor of approximately 3.5. We found that the mass spectra of the SMC based on both the luminous mass and the virial mass are steeper than dN/dM ∝ M−2, suggesting that most of the molecular mass of the SMC is contained in low-mass clouds. Using the virial masses of the SMC CO clouds identified by CPROPS, we derived a CO-to-H2 conversion factor of αCOvir = 10.5 ± 5 M⊙ (K km s−1 pc2)−1, adopting the measured SMC CO(2−1)/CO(1−0) ratio of one. Regarding the dust clouds for which we had identified the corresponding CO emission, we determined an upper limit of the dust-based conversion factor for the SMC of αCOdust = 28 ± 15 M⊙ (Kkm s−1 pc2)−1 at 12 pc resolution. These conversion factors, determined by two alternative methods, are about 2.5 and 6.5 times larger than the canonical Galactic conversion factor. For molecular clouds where there is both a dust and a virial mass, we found that the clouds appear to be in approximate gravitational virial equilibrium. Finally, we found that about half of the clouds identified by CPROPS are associated with ongoing star formation, either YSOs or HII regions, but also that close to half the clouds are not. Most of the YSOs in the clouds are in their first evolutive stages.
The X-ray synchrotron rims in Cassiopeia A narrow with energy
Authors: Picquenot A. , Williams B. J. , Acero F. , Guest B. T.
Published: February 2023

Context. Some young supernova remnants exhibit thin filaments of X-ray synchrotron radiation coinciding with the forward shock due to accelerated electrons interacting with the local magnetic field. The two main models accounting for the radial brightness evolution of these filaments differ in their prediction of the narrowing (or not) of the filaments with increasing photon energy.

Aims. In this paper, we report our observation of such a narrowing of the synchrotron filaments in Cassiopeia A at X-ray energies, and how this finding could inform our understanding of the mechanisms at stake in their formation.

Methods. We used a new blind-source-separation method on the 1 Ms Chandra observation of Cassiopeia A in order to obtain detailed and unpolluted images of the synchrotron emission in three energy bands. We then extracted the profiles of several filaments at the forward shock and the reverse shock to estimate and compare their widths.

Results. We find that there is indeed a narrowing with energy of the synchrotron filaments both at the forward and at the reverse shocks in Cassiopeia A. The energy dependency of this narrowing seems stronger at high energy, which is indicative of a damping effect that is also suggested by radio observations.
Discovering strongly lensed quasar candidates with catalogue-based methods from DESI Legacy Surveys
Authors: He Zizhao , Li Nan , Cao Xiaoyue , Li Rui , Zou Hu , Dye Simon
Published: February 2023

Context. The Hubble tension, revealed by a ~5σ discrepancy between measurements of the Hubble-Lemaitre constant among observations of the early and local Universe, is one of the most significant problems in modern cosmology. In order to better understand the origin of this mismatch, independent techniques to measure H0, such as strong lensing time delays, are required. Notably, the sample size of such systems is key to minimising the statistical uncertainties and cosmic variance, which can be improved by exploring the datasets of large-scale sky surveys such as Dark Energy Spectroscopic Instrument (DESI).

Aims. We identify possible strong lensing time-delay systems within DESI by selecting candidate multiply imaged lensed quasars from a catalogue of 24 440 816 candidate QSOs contained in the ninth data release of the DESI Legacy Imaging Surveys (DESI-LS).

Methods. Using a friend-of-friends-like algorithm on spatial co-ordinates, our method generates an initial list of compact quasar groups. This list is subsequently filtered using a measure of the similarity of colours among a group’s members and the likelihood that they are quasars. A visual inspection finally selects candidate strong lensing systems based on the spatial configuration of the group members.

Results. We identified 620 new candidate multiply imaged lensed quasars (101 grade-A, 214 grade-B, 305 grade-C). This number excludes 53 known spectroscopically confirmed systems and existing candidate systems identified in other similar catalogues. When available, these new candidates will be further checked by combining the spectroscopic and photometric data from DESI.
The CARMENES search for exoplanets around M dwarfs
Authors: Lafarga M. , Ribas I. , Zechmeister M. , Reiners A. , López-Gallifa Á. , Montes D. , Quirrenbach A. , Amado P. J. , Caballero J. A. , Azzaro M. , Béjar V. J. S. , Hatzes A. P. , Henning Th. , Jeffers S. V. , Kaminski A. , Kürster M. , Schöfer P. , Schweitzer A. , Tabernero H. M. , Osorio M. R. Zapatero
Published: February 2023

Context. Radial velocities (RVs) measured from high-resolution stellar spectra are routinely used to detect and characterise orbiting exoplanet companions. The different lines present in stellar spectra are created by several species, which are non-uniformly affected by stellar variability features such as spots or faculae. Stellar variability distorts the shape of the spectral absorption lines from which precise RVs are measured, posing one of the main problems in the study of exoplanets.

Aims. In this work we aim to study how the spectral lines present in M dwarfs are independently impacted by stellar activity.

Methods. We used CARMENES optical spectra of six active early- and mid-type M dwarfs to compute line-by-line RVs and study their correlation with several well-studied proxies of stellar activity.

Results. We are able to classify spectral lines based on their sensitivity to activity in five M dwarfs displaying high levels of stellar activity. We further used this line classification to compute RVs with activity-sensitive lines and less sensitive lines, enhancing or mitigating stellar activity effects in the RV time series. For specific sets of the least activity-sensitive lines, the RV scatter decreases by ~2 to 5 times the initial one, depending on the star. Finally, we compare these lines in the different stars analysed, finding the sensitivity to activity to vary from star to star.

Conclusions. Despite the high density of lines and blends present in M dwarf stellar spectra, we find that a line-by-line approach is able to deliver precise RVs. Line-by-line RVs are also sensitive to stellar activity effects, and they allow for an accurate selection of activity-insensitive lines to mitigate activity effects in RV. However, we find stellar activity effects to vary in the same insensitive lines from star to star.
Key Techniques of the Digital Energy Internet Park: An Example of State Grid Energy Internet Rongchuang Park in Lanzhou
Authors: Zhang Xu , Zhao Bo , Cui Ajun , Li Chunliang , Wang Gang , Li Zhipeng , Li Fupeng , Guo Mingkang
Published: February 2023

The construction of the digital energy internet is of great significance to the formation of the global energy internet. This paper uses the Rongchuang park of state grid Lanzhou power supply company as an example. Particularly, the key techniques from “source, grid, load, and storage” were summarized. It is key for the building of the energy internet Rongchuang park to increase the proportion of clean energy production and consumption, improve the intelligent level of the power grid, fully tap the potential of load side energy conservation and peak shaving regulation, and promote the system flexibility by energy storage techniques. This work supports the technological development and breakthrough of the energy internet park.
Structured Reporting in Cross-Sectional Imaging of the Heart: Reporting Templates for CMR Imaging of Ischemia and Myocardial Viability and for Cardiac CT Imaging of Coronary Heart Disease and TAVI Planning
Authors: Soschynski Martin , Bunck Alexander Christian , Beer Meinrad , Kloempken Steffen , Schlett Christopher L , Baeßler Bettina , Kröger Jan Robert , Persigehl Thorsten , Pinto dos Santos Daniel , Steinmetz Michael , Niehaus Adelheid , Bamberg Fabian , Ley Sebastian , Tiemann Klaus , Beerbaum Philipp , Lotz Joachim , Maintz David , Kloth Christopher , Brunner Horst , Ritter Christian O
Published: February 2023

Background Structured reporting allows a high grade of standardization and thus a safe and unequivocal report communication. In the past years, the radiological societies have started several initiatives to base radiological reports on structured reporting rather than free text reporting.

Methods Upon invitation of the working group for Cardiovascular Imaging of the German Society of Radiology, in 2018 an interdisciplinary group of Radiologists, Cardiologists, Pediatric Cardiologists and Cardiothoracic surgeons -all experts on the field of cardiovascular MR and CT imaging- met for interdisciplinary consensus meetings at the University Hospital Cologne. The aim of these meetings was to develop and consent templates for structured reporting in cardiac MR and CT of various cardiovascular diseases.

Results Two templates for structured reporting of CMR in ischemia imaging and vitality imaging and two templates for structured reporting of CT imaging for planning Transcatheter Aortic Valve Implantation (TAVI; pre-TAVI-CT) and coronary CT were discussed, consented and transferred to a HTML 5/IHR MRRT compatible format. The templates were made available for free use on the website www.befundung.drg.de.

Conclusion This paper suggests consented templates in German language for the structured reporting of cross-sectional CMR imaging of ischemia and vitality as well as reporting of CT imaging pre-TAVI and coronary CT. The implementation of these templates is aimed at providing a constant level of high reporting quality and increasing the efficiency of report generation as well as a clinically based communication of imaging results.

Key points: 

Zitierweise
Zwischen Wunsch und Wirklichkeit: Mehr Effizienz durch Ambulantisierung von Eingriffen in der Kinderurologie
Authors: Hofmann Aybike , Badelt Gregor , Rösch Wolfgang H.
Published: February 2023

Die „Ambulantisierung“ von Eingriffen und Leistungen gewinnt derzeit zunehmend an
Interesse. Zukünftig sollen gemäß IGES-Gutachten mehr als 2000 Eingriffe in den Katalog für
ambulantes Operieren aufgenommen werden. Dies bedeutet auch für den (kinder-)urologischen
Bereich eine deutliche Zunahme ambulant durchführbarer Eingriffe. Allerdings hängt die
Umsetzbarkeit, insbesondere in der Kinderurologie, von vielen spezifischen personellen,
organisatorischen und strukturellen Voraussetzungen ab.
Comparison of the efficacy of pioglitazone and metformin on
ultrasound grade and liver enzymes level in patients with non-alcoholic fatty
liver disease: A randomized controlled clinical trial
Authors: Khoshbaten Manouchehr , Beheshtirouy Samineh , Shayanrad Shahrzad , Gharekhani Afshin , Rezaee Haleh
Published: February 2023

Background This study aimed to evaluate the effectiveness of metformin and
pioglitazone in combination with vitamin E on sonography grade and liver enzymes
level in patients with non-alcoholic fatty liver disease.

Methods A randomized controlled clinical trial was designed with 68
patients diagnosed with non-alcoholic fatty liver disease by sonography and
clinical examinations. Sixty-eight patients were randomly divided into two
groups; 34 were assigned to receive 15 mg of pioglitazone per day and 34
were assigned to receive 1000 mg of metformin per day for 6 months. All
of the patients received vitamin E at a dose of 800 IU daily for six months. The
sonography grade of fatty liver and the levels of alanine aminotransferase and
aspartate aminotransferase of patients were evaluated at baseline, and within
three and six months after initiation of the intervention.

Results The use of metformin or pioglitazone in combination with vitamin E
decreased the sonography grade of non-alcoholic fatty liver disease patients
after 6 months of treatment (p-value<0.05); however, patients in
metformin group benefit more compared to pioglitazone group. Patients who
received metformin and vitamin E had a significant reduction in the levels of
alanine aminotransferase and aspartate aminotransferase (p-value<0.05).
There were no significant changes in the liver enzymes level of the patients who
received pioglitazone and vitamin E (p-value>0.05).

Major conclusion The concomitant use of metformin and vitamin E
significantly improves the sonography grade of fatty liver and the level of
liver enzymes in patients with non-alcoholic fatty liver disease.
Psychische Belastungen bei Angehörigen von Menschen mit
psychischen Erkrankungen während der COVID-19 Pandemie
Authors: Jahn Ina , Jelinek Lena , Moritz Steffen , Stengler Katarina
Published: February 2023

Anliegen Die COVID-19 Pandemie stellt für die meisten
Menschen eine Belastung dar – insbesondere jedoch für psychisch
Erkrankte und deren Angehörige. Ziel der vorliegenden Studie war es,
spezifische Belastungen sowie Bewältigungsstrategien bei
Angehörigen von Menschen mit psychischen Erkrankungen zu
untersuchen.

Methoden  Für die Studie wurde ein
Fragebogen zur Erfassung Corona-Pandemie-bedingter Einflüsse auf
Belastungen von Angehörigen von Menschen mit psychischen Erkrankungen
entwickelt. Insgesamt nahmen 228 Angehörige nahmen zwischen März
bis Juni 2021 an der Befragung teil.

Ergebnisse  Mehr als
87% der Angehörigen berichteten, dass sie von der psychischen
Erkrankung ihrer erkrankten Angehörigen belastet seien. Viele der
Befragten beschrieben subjektiv hilfreiche Bewältigungsstrategien wie
Wertschätzung gesunder Anteile.

Schlussfolgerung
 Für Angehörige von Menschen mit psychischen
Erkrankungen sollten in Krisenzeiten, wie die der COVID-19 Pandemie
Versorgungsstrukturen und Unterstützungsangebote sensibel ausgerichtet
und kontinuierlich vorgehalten werden.
Papillary Thyroid Microcarcinoma: Insights from a Cohort of 257
Thyroidectomized Patients
Authors: Scherer Henrique Cabral , Fernandes Paula Martins , Scheffel Rafael Selbach , Zanella André Borsatto , Maia Ana Luiza , Dora Jose Miguel
Published: February 2023

Papillary thyroid microcarcinoma management evolved, and less aggressive
strategies are now considered. Questions, however, remain on these
tumors’ behavior, particularly on developing countries' real
ground healthcare scenarios. Our aim is to gather insights on the natural
history of papillary thyroid microcarcinoma on patients treated with
thyroidectomy in Brazil. Consecutive patients diagnosed with papillary thyroid
microcarcinoma had their clinical characteristics, interventions, and outcomes
described. Patients were classified as incidental or nonincidental based on the
diagnosis after or before surgery, respectively. A sum of 257 patients were
included, 84.0% of which were women, and the mean age was of
48.3±13.5 years. The mean tumor size was of
0.68±0.26 cm, 30.4% were multifocal, 24.5% had
cervical metastasis, and 0.4% distant metastasis. The nonincidental and
incidental tumors differed in tumor size (0.72±0.24 and
0.60±0.28 cm, respectively, p=0.003) and in presence of
cervical metastasis (31.3% and 11.9%, respectively,
p<0.001). Male sex, nonincidental diagnosis, and younger age were
independent predictors of cervical metastasis. After 5.5 years (P25–75
2.5–9.7) of follow-up, only 3.8% of patients had persistent
structural disease (3.4% cervical). Predictors of persistent disease at
multivariate analysis included cervical metastasis and multicentricity. In
conclusion, incidental and nonincidental papillary thyroid microcarcinoma
patients of the population studied displayed excellent outcomes. Cervical
metastasis and multicentricity were frequent findings and prognostic factors for
persistent disease.
Electrochemical Difunctionalization of Alkenes
Authors: Qin Jing-Hao , Li Jin-Heng , Nan Ning
Published: February 2023

The electrochemical alkene difunctionalization reaction has become a powerful and sustainable tool for the efficient construction of vicinal difunctionalized structures in organic synthesis. Since only electrons are used as the redox agents, electrochemical alkene difunctionalization avoids the need for additional redox catalysts, metal catalysts, or chemical oxidants and does not generate chemical waste. Herein we summarize the latest contributions in the electrochemical difunctionalization of alkenes over the last 3–4 years. We discuss in detail the reaction features, scope, limitations, and mechanistic rationalizations of three categories of alkene difunctionalization methods: (1) electrochemical alkene difunctionalization terminated by nucleophiles, (2) electrochemical difunctionalization of alkenes terminated by radicals, and (3) electrochemical alkene difunctionalization terminated by functionality migration.

1 Introduction

2 Electrochemical Alkene Difunctionalization Terminated by Nucleophiles

2.1 Sulfonylative Difunctionalization of Alkenes

2.2 Sulfurizative/Sulfoxidative Difunctionalization of Alkenes

2.3 Azidotetrazolation of Alkenes

2.4 Trifluoromethylative Difunctionalization of Alkenes

2.5 Diarylation of Alkenes

3 Electrochemical Difunctionalization of Alkenes Terminated by Radicals

3.1 Direct Radical-Coupling-Enabled Alkene Difunctionalization

3.2 Metal-Mediated Radical Transfer Coupling Enabled Alkene Difunctionalization

3.3 Metalloid-Mediated Radical Transfer Coupling Enabled Alkene Difunctionalization

4 Electrochemical Alkene Difunctionalization Terminated by Functionality Migration

5 Summary and Outlook
How active are right-wing party members? Portuguese right-wing delegates, from a comparative and a General Incentives Model (GIM) perspective
Authors: do Espírito Santo Paula , Ferreira Ana Paula
Published: February 2023

This contribution explores the role of the incentives and benefits of party affiliation, along with the ideological reasons for being politically active, in particular as a party delegate. The rational for party affiliation and for activism has developed over recent decades, ranging from individual to collective reasons. The incentives that explain activism have been an essential part of the discussion on the reasons for becoming a party member, particularly following the seminal study on the General Incentives Model (GIM)’s, Seyd and Whiteley (1992). Later developments from Whiteley et al. (2019) provided evidence on the activism of radical political forces, as is the case of UKIP in the United Kingdom. Following the GIM framework, this study explores these themes within a Portuguese context, and from a comparative perspective. To date, investigations in this field have rarely focused on Portugal. The research question is: how do delegates view their party’s incentives and benefits, and how is this influenced by their ideological self-positioning on the left–right scale? We argue that the larger the party, the lower the members’ assessment will be of the incentives and benefits achieved. In methodological terms, this study is based on the MAPP project and surveys, applied to Portuguese political party members, including delegates from right-wing parties. The relevance of this article lies in the application of the GIM to delegates of right-wing political parties, in a comparative perspective, considering a downward trend and a Southern European country that has, to date, been little explored in this context (Sierens et al. 2022). The goal is to find evidence of how right-wing party members and delegates view the incentives and benefits that play a role in party activism.
Bakry–Émery Ricci curvature, X-minimal hypersurfaces, and near horizon geometries
Authors: Moore Kenneth , Woolgar Eric
Published: February 2023

Motivated by the extreme black hole near horizon geometry equation and the Ellis–Ehlers equation of mathematical cosmology, we prove a Bakry–Émery generalization of a theorem of Frankel that closed minimal hypersurfaces in a complete manifold with a suitable curvature bound must intersect. We do not assume that the Bakry–Émery vector field is of gradient type. We also present splitting theorems of warped product type for manifolds bounded by hypersurfaces obeying Bakry–Émery curvature bounds.
Francium ion source with novel methods of target heating and beam characterization
Authors: Ozawa N. , Nagahama H. , Sakemi Y.
Published: February 2023

We have developed a novel ion source and beam diagnostic system for the production and detection of radioactive francium (Fr) isotopes. The Fr ions are produced using a fusion–evaporation reaction at the RIKEN Nishina Center, Japan. The installation of an infrared heater has enabled a precise and rapid control of the target temperature, and the newly developed diagnostic system allows for a quantitative characterization of the extracted ion beam. With the new system, an analysis of the Fr208−211 isotopes has been performed. Additionally, the flux of Fr210 ions has been estimated as 6.7 × 106 s−1 corresponding to an extraction efficiency of 24.5% and a beam purity of 1.6 × 10−5.
Improved and Always Improving: Reference Formulations for Thermophysical Properties of Water
Authors: Harvey Allan H. , Hrubý Jan , Meier Karsten
Published: February 2023

This Review presents the state of knowledge of the thermophysical properties of water in all its phases and the reference formulations that provide standardized, recommended values of these properties for science and industry. The main focus is the standard formulations adopted by the International Association for the Properties of Water and Steam (IAPWS), but some properties are covered for which IAPWS has not yet adopted recommendations. It is emphasized that, despite many advances over the last 100 years, there is room for further improvement, and current weaknesses and opportunities for advancing knowledge are discussed. Particular attention is given to the formulation for thermodynamic properties of fluid water known as IAPWS-95, which is planned to be replaced in the coming years. Additional topics include properties of heavy water and seawater and the growing ability of molecular modeling to provide properties at conditions where experimental measurements are difficult or inaccurate.
ZnO-6LiF/polystyrene composite scintillator for thermal neutron radiation detection
Authors: Sahani R. M. , Pandya Arun , Dixit Ambesh
Published: February 2023

We report the preparation of the ZnO-6LiF composite with a polystyrene (PS) polymer as a host using the solution mixing process. 6LiF acts as a converter material that absorbs a thermal neutron and produces alpha particles, which excites ZnO micro-particles, resulting in UV–vis photons’ emission. The free-standing ZnO-6LiF/PS composite film is coupled to a photomultiplier tube (PMT). 241Am-Be (1Ci) is used as the neutron radiation source for measuring the response. We compared the response of the composite scintillator consisting of (i) natural LiF and (ii) 95% 6Li enriched LiF (6LiF). The increased pulse heights are recorded for 95% 6Li enriched, i.e., 6LiF converter. It confirms the generation of alpha particles after the absorption of a neutron in 6LiF. Furthermore, ZnO and 6LiF are considered in different weight proportions, 2:1, 1:1, and 1:2, keeping the total loading 50% (w/w) of polystyrene. The ZnO:6LiF (1:1)/PS composite showed higher scintillation pulse heights than the other two composites. Repetitive measurements are performed for the ZnO-6LiF(1:1)/PS composite, showing ±5% variation in respective responses. We also investigated the impact of different counting times and source-to-detector responses for the ZnO-6LiF(1:1)/PS composite. The response increases linearly with neutron dose, exhibiting a sensitivity of ∼203 counts/μSv. Neutron measurement counts at different source-to-detector distances have a similar trend as that of neutron dose measured by using a neutron dosimeter. Thus, this work demonstrated the potential of the ZnO-6LiF/PS composite, coupled to PMT for detecting thermal neutron radiation.
Invited article: X-ray phase contrast imaging in inertial confinement fusion and high energy density research
Authors: Montgomery David S.
Published: February 2023

X-ray phase contrast imaging (XPCI) provides enhanced image contrast beyond absorption-based x-ray imaging alone due to refraction and diffraction from gradients in the object material density. It is sensitive to small variations in density, such as internal voids, cracks, grains, defects, and material flow, as well as to stronger density variations such as from a shock wave. Beyond its initial use in biology and materials science, XPCI is now routinely used in inertial confinement fusion (ICF) and high energy density (HED) research, first to characterize ICF capsules and targets, and later applied in dynamic experiments, where coherent x-ray sources, ultrafast x-ray pulses, and high temporal and spatial resolution are required. In this Review article, XPCI image formation theory is presented, its diverse use in ICF and HED research is discussed, the unique requirements for ultrafast XPCI imaging are given, as well as current challenges and issues in its use.
Flow under vertical sluice gates: Flow stability at large gate opening and disambiguation of partial dam-break multiple solutions
Authors: Lazzarin Tommaso , Viero Daniele Pietro , Defina Andrea , Cozzolino Luca
Published: February 2023

The present paper deals with two open issues concerning the free orifice flow under vertical sluice gates, namely, the flow stability at large gate openings and the disambiguation of multiple solutions in the case of partial dam-break. The study of these problems, which are mutually connected, is based on ad hoc laboratory experiments and numerical simulations with a computational fluid dynamics model tracking the free surface with the two-phase volume of fluid method. A series of quasi-steady states is used to assess the threshold of relative gate openings that determines the passage from orifice flow to non-interacting flow; in addition, a set of dam-break experiments with partial gate opening (i.e., lower than the initial upstream water level) is performed to find reliable criteria to disambiguate multiple exact solutions supplied by the one-dimensional shallow water theory. It is found that the dependence of contraction and discharge coefficients on the relative gate opening has a dramatic impact on the stability of orifice flow at large gate openings.
Transition to hyperchaos and rare large-intensity pulses in Zeeman laser
Authors: Leo Kingston S. , Balcerzak Marek , Dana Syamal K. , Kapitaniak Tomasz
Published: February 2023

A discontinuous transition to hyperchaos is observed at discrete critical parameters in the Zeeman laser model for three well known nonlinear sources of instabilities, namely, quasiperiodic breakdown to chaos followed by interior crisis, quasiperiodic intermittency, and Pomeau–Manneville intermittency. Hyperchaos appears with a sudden expansion of the attractor of the system at a critical parameter for each case and it coincides with triggering of occasional and recurrent large-intensity pulses. The transition to hyperchaos from a periodic orbit via Pomeau–Manneville intermittency shows hysteresis at the critical point, while no hysteresis is recorded during the other two processes. The recurrent large-intensity pulses show characteristic features of extremes with their height larger than a threshold and the probability of a rare occurrence. The phenomenon is robust to weak noise although the critical parameter of transition to hyperchaos shifts with noise strength. This phenomenon appears as common in many low dimensional systems as reported earlier by Chowdhury et al. [Phys. Rep. 966, 1–52 (2022)], there the emergent large-intensity events or extreme events dynamics have been recognized simply as chaotic in nature although the temporal dynamics shows occasional large deviations from the original chaotic state in many examples. We need a new metric, in the future, that would be able to classify such significantly different dynamics and distinguish from chaos.
Fast and flexible control of beam longitudinal phase space for high-repetition-rate x-ray free-electron lasers
Authors: Zhang Zhen , Snively Emma , Dolgashev Valery , Huang Zhirong
Published: February 2023

The wide-ranging requirements for the photon properties from multiple beamlines in superconducting based free-electron lasers (FELs) demand more challenging beam manipulation techniques. Shot-by-shot control of electron beam bunch length and peak current at high repetition rate up to megahertz is highly desired. In this paper, we present a comprehensive study of a method based on a 2-m-long normal conducting radio-frequency cavity to achieve fast and flexible control of beam compression and realize the full potential of the facility, including theoretical analysis, beam dynamics simulations, and conceptual cavity design for the Linac Coherent Light Source II and its high-energy upgrade. We illustrate the physical mechanism of the chirping cavity on the control of the final beam compression and propose methods to lower the requirements for the cavity parameters. The application of this method will allow tailored photon properties of individual beamlines to optimize their performance and drastically improve the multiplexing capabilities of a high-repetition rate FEL facility.
Long-range interactions of aromatic molecules with alkali-metal and alkaline-earth-metal atoms
Authors: Shirkov Leonid , Tomza Michał
Published: February 2023

The isotropic and anisotropic coefficients Cnl,m of the long-range spherical expansion ∼1/Rn (R—the intermolecular distance) of the dispersion and induction intermolecular energies are calculated using the first principles for the complexes containing an aromatic molecule (benzene, pyridine, furan, and pyrrole) and alkali-metal (Li, Na, K, Rb, and Cs) or alkaline-earth-metal (Be, Mg, Ca, Sr, and Ba) atoms in their electronic ground states. The values of the first- and second-order properties of the aromatic molecules are calculated using the response theory with the asymptotically corrected LPBE0 functional. The second-order properties of the closed-shell alkaline-earth-metal atoms are obtained using the expectation-value coupled cluster theory and of the open-shell alkali-metal atoms using analytical wavefunctions. These properties are used for the calculation of the dispersion Cn,displ,m and induction Cn,indl,m coefficients (Cnl,m=Cn,displ,m+Cn,indl,m) with n up to 12 using the available implemented analytical formulas. It is shown that the inclusion of the coefficients with n > 6 is important for reproducing the interaction energy in the van der Waals region at R ≈ 6 Å. The reported long-range potentials should be useful for constructing the analytical potentials valid for the whole intermolecular interaction range, which are needed for spectroscopic and scattering studies.
Magnetostress and multicaloric effect in Ni44.1Co5.0Mn36.1In13.4Cu1.4 polycrystalline alloy
Authors: Liu Jian , Fan Ze-Ming , Qian Han-Yang , Yan Hai-Le
Published: February 2023

In this Letter, we report on a large magnetic field-induced stress of 14.4 MPa/T and a low stress hysteresis of 50 MPa in a polycrystalline Ni44.1Co5.0Mn36.1In13.4Cu1.4 alloy, rendering it as a promising candidate for high-energy output and high-efficient actuators. The large magnetostress mainly originates from the large transformation entropy change of 15.4 J/(kg K) and the high sensitivity of phase transformation temperature to the magnetic field of −9.2 K/T. Furthermore, we have explored the possibility by adopting multicaloric strategy to enhance the transformation reversibility and widen the cooling temperature window. Unexpectedly, the application of the magnetic field has little impact on the elastocaloric temperature change, which might be ascribed to the large magnetization character of ferromagnetic austenite phase and the non-synergic spin-lattice transformation behavior in the Ni44.1Co5.0Mn36.1In13.4Cu1.4 alloy.
A neural network potential with self-trained atomic fingerprints: A test with the mW water potential
Authors: Guidarelli Mattioli Francesco , Sciortino Francesco , Russo John
Published: February 2023

We present a neural network (NN) potential based on a new set of atomic fingerprints built upon two- and three-body contributions that probe distances and local orientational order, respectively. Compared with the existing NN potentials, the atomic fingerprints depend on a small set of tunable parameters that are trained together with the NN weights. In addition to simplifying the selection of the atomic fingerprints, this strategy can also considerably increase the overall accuracy of the network representation. To tackle the simultaneous training of the atomic fingerprint parameters and NN weights, we adopt an annealing protocol that progressively cycles the learning rate, significantly improving the accuracy of the NN potential. We test the performance of the network potential against the mW model of water, which is a classical three-body potential that well captures the anomalies of the liquid phase. Trained on just three state points, the NN potential is able to reproduce the mW model in a very wide range of densities and temperatures, from negative pressures to several GPa, capturing the transition from an open random tetrahedral network to a dense interpenetrated network. The NN potential also reproduces very well properties for which it was not explicitly trained, such as dynamical properties and the structure of the stable crystalline phases of mW.
Flow control of an elastically mounted square cylinder by using an attached flexible plate
Authors: Shao Jiang Yan , Wen Jia Dong , Zhang Lu
Published: February 2023

This work numerically investigates the flow control of an elastically mounted square cylinder by using an attached plate placing downstream. The flow control effect by using a long solid/flexible plate for a circular cylinder has been widely discussed. However, the effect of a short plate is not clear. In addition, few knowledge is known for VIV (vortex-induced vibration) suppression effect for a square cylinder by using a solid/flexible plate. The present work systematically studies the influence of plate length and flexibility on VIV suppression for an elastically mounted square cylinder at Reynolds number 150. First, the effect of a solid plate with non-dimensional length varying in a wide range 0.5≤L*≤3.0 is analyzed. Significant VIV suppression can be achieved by using an attached solid plate, even with a plate at a short length. The influence of flexibility is more complex. A short flexible plate is less effective than a solid plate with the same length. On the other hand, a long flexible plate with medium flexibility can further enhance VIV suppression. A maximum 96% reduction in the vibration amplitude can be achieved by using a long flexible plate with optimal flexibility. Additionally, two VIV suppression mechanisms for an elastically mounted square cylinder with an attached plate are concluded, and the influence of flexibility for both short and long plates is also analyzed.
Representation and conservation of angular momentum in the Born–Oppenheimer theory of polyatomic molecules
Authors: Littlejohn Robert , Rawlinson Jonathan , Subotnik Joseph
Published: February 2023

This paper concerns the representation of angular momentum operators in the Born–Oppenheimer theory of polyatomic molecules and the various forms of the associated conservation laws. Topics addressed include the question of whether these conservation laws are exactly equivalent or only to some order of the Born–Oppenheimer parameter κ = (m/M)1/4 and what the correlation is between angular momentum quantum numbers in the various representations. These questions are addressed in both problems involving a single potential energy surface and those with multiple, strongly coupled surfaces and in both the electrostatic model and those for which fine structure and electron spin are important. The analysis leads to an examination of the transformation laws under rotations of the electronic Hamiltonian; of the basis states, both adiabatic and diabatic, along with their phase conventions; of the potential energy matrix; and of the derivative couplings. These transformation laws are placed in the geometrical context of the structures in the nuclear configuration space that are induced by rotations, which include the rotational orbits or fibers, the surfaces upon which the orientation of the molecule changes but not its shape, and the section, an initial value surface that cuts transversally through the fibers. Finally, it is suggested that the usual Born–Oppenheimer approximation can be replaced by a dressing transformation, that is, a sequence of unitary transformations that block-diagonalize the Hamiltonian. When the dressing transformation is carried out, we find that the angular momentum operator does not change. This is a part of a system of exact equivalences among various representations of angular momentum operators in Born–Oppenheimer theory. Our analysis accommodates large-amplitude motions and is not dependent on small-amplitude expansions about an equilibrium position. Our analysis applies to noncollinear configurations of a polyatomic molecule; this covers all but a subset of measure zero (the collinear configurations) in the nuclear configuration space.
lncRNA
BREA2
promotes metastasis by disrupting the WWP2-mediated ubiquitination of Notch1
Authors: Zhang Zhen , Lu Yun-xin , Liu Fangzhou , Sang Lingjie , Shi Chengyu , Xie Shaofang , Bian Weixiang , Yang Jie-cheng , Yang Zuozhen , Qu Lei , Chen Shi-yi , Li Jun , Yang Lu , Yan Qingfeng , Wang Wenqi , Fu Peifen , Shao Jianzhong , Li Xu , Lin Aifu
Published: February 2023

Notch has been implicated in human cancers and is a putative therapeutic target. However, the regulation of Notch activation in the nucleus remains largely uncharacterized. Therefore, characterizing the detailed mechanisms governing Notch degradation will identify attractive strategies for treating Notch-activated cancers. Here, we report that the long noncoding RNA (lncRNA)
BREA2
drives breast cancer metastasis by stabilizing the Notch1 intracellular domain (NICD1). Moreover, we reveal WW domain containing E3 ubiquitin protein ligase 2 (WWP2) as an E3 ligase for NICD1 at K1821 and a suppressor of breast cancer metastasis. Mechanistically,
BREA2
impairs WWP2–NICD1 complex formation and in turn stabilizes NICD1, leading to Notch signaling activation and lung metastasis.
BREA2
loss sensitizes breast cancer cells to inhibition of Notch signaling and suppresses the growth of breast cancer patient-derived xenograft tumors, highlighting its therapeutic potential in breast cancer. Taken together, these results reveal the lncRNA
BREA2
as a putative regulator of Notch signaling and an oncogenic player driving breast cancer metastasis.
Cspg4
high

microglia contribute to microgliosis during neurodegeneration
Authors: Liu Ya-jing , Ding Yu , Yin Yan-qing , Xiao Hui , Hu Gang , Zhou Jia-wei
Published: February 2023

Microglia play a critical role in the pathogenic process of neurodegenerative diseases, such as Parkinson’s disease (PD) and Alzheimer’s disease (AD). Upon pathological stimulation, microglia are converted from a surveillant to an overactivated phenotype. However, the molecular characters of proliferating microglia and their contributions to the pathogenesis of neurodegeneration remain unclear. Here, we identify chondroitin sulfate proteoglycan 4 (
Cspg4,
also known as neural/glial antigen 2)-expressing microglia as a specific subset of microglia with proliferative capability during neurodegeneration. We found that the percentage of

Cspg4
+

microglia was increased in mouse models of PD. The transcriptomic analysis of

Cspg4
+

microglia revealed that the subcluster

Cspg4
high

microglia displayed a unique transcriptomic signature, which was characterized by the enrichment of orthologous cell cycle genes and a lower expression of genes responsible for neuroinflammation and phagocytosis. Their gene signatures were also distinct from that of known disease-associated microglia. The proliferation of quiescent

Cspg4
high

microglia was evoked by pathological α-synuclein. Following the transplantation in the adult brain with the depletion of endogenous microglia,

Cspg4
high

microglia grafts showed higher survival rates than their
Cspg4
−
 counterparts. Consistently,

Cspg4
high

microglia were detected in the brain of AD patients and displayed the expansion in animal models of AD. These findings suggest that

Cspg4
high

microglia are one of the origins of microgliosis during neurodegeneration and may open up a avenue for the treatment of neurodegenerative diseases.
Directing smartphone use through the self-nudge app one sec
Authors: Grüning David J. , Riedel Frederik , Lorenz-Spreen Philipp
Published: February 2023

Research suggests various associations of smartphone use with a range of physical, psychological, and performance dimensions. Here, we test one sec, a self-nudging app that is installed by the user in order to reduce the mindless use of selected target apps on the smartphone. When users attempt to open a target app of their choice, one sec interferes with a pop-up, which combines a deliberation message, friction by a short waiting time, and the option to dismiss opening the target app. In a field-experiment, we collected behavioral user data from 280 participants over 6 wk, and conducted two surveys before and after the intervention span. one sec reduced the usage of target apps in two ways. First, on average 36% of the times participants attempted opening a target app, they closed that app again after one sec interfered. Second, over the course of 6 wk, users attempted to open target apps 37% less than in the first week. In sum, one sec decreased users’ actual opening of target apps by 57% after six consecutive weeks. Afterward, participants also reported spending less time with their apps and indicated increased satisfaction with their consumption. To disentangle one sec’s effects, we tested its three psychological features in a preregistered online experiment (N = 500) that measured the consumption of real and viral social media video clips. We found that providing the additional option to dismiss the consumption attempt had the strongest effect. While the friction by time delay also reduced consumption instances, the deliberation message was not effective.
The RecA-directed recombination pathway of natural transformation initiates at chromosomal replication forks in the pneumococcus
Authors: Johnston Calum H. G. , Hope Rachel , Soulet Anne-Lise , Dewailly Marie , De Lemos David , Polard Patrice
Published: February 2023

Homologous recombination (HR) is a crucial mechanism of DNA strand exchange that promotes genetic repair and diversity in all kingdoms of life. Bacterial HR is driven by the universal recombinase RecA, assisted in the early steps by dedicated mediators that promote its polymerization on single-stranded DNA (ssDNA). In bacteria, natural transformation is a prominent HR-driven mechanism of horizontal gene transfer specifically dependent on the conserved DprA recombination mediator. Transformation involves internalization of exogenous DNA as ssDNA, followed by its integration into the chromosome by RecA-directed HR. How DprA-mediated RecA filamentation on transforming ssDNA is spatiotemporally coordinated with other cellular processes remains unknown. Here, we tracked the localization of fluorescent fusions to DprA and RecA in
Streptococcus pneumoniae
and revealed that both accumulate in an interdependent manner with internalized ssDNA at replication forks. In addition, dynamic RecA filaments were observed emanating from replication forks, even with heterologous transforming DNA, which probably represent chromosomal homology search. In conclusion, this unveiled interaction between HR transformation and replication machineries highlights an unprecedented role for replisomes as landing pads for chromosomal access of tDNA, which would define a pivotal early HR step for its chromosomal integration.
Recovery and facets for deformation twins in minerals and metals
Authors: Hirth John P. , Xie Dongyue , Hirth Greg , Wang Jian
Published: February 2023

Type II and IV twins with irrational twin boundaries are studied by high-resolution transmission electron microscopy in two plagioclase crystals. The twin boundaries in these and in NiTi are found to relax to form rational facets separated by disconnections. The topological model (TM), amending the classical model, is required for a precise theoretical prediction of the orientation of the Type II/IV twin plane. Theoretical predictions also are presented for types I, III, V, and VI twins. The relaxation process that forms a faceted structure entails a separate prediction from the TM. Hence, faceting provides a difficult test for the TM. Analysis of the faceting by the TM is in excellent agreement with the observations.