bluuebunny/crossref_metadata_2025 huggingface dataset:
Matching with semi-bandits
Authors: Kasy Maximilian , Teytelboym Alexander
Published: September 2022

We consider an experimental setting in which a matching of resources to participants has to be chosen repeatedly and returns from the individual chosen matches are unknown, but can be learned. Our setting covers two-sided and one-sided matching with (potentially complex) capacity constraints, such as refugee resettlement, social housing allocation, and foster care. We propose a variant of the Thompson sampling algorithm to solve such adaptive combinatorial allocation problems. We give a tight, prior-independent, finite-sample bound on the expected regret for this algorithm. Although the number of allocations grows exponentially in the number of matches, our bound does not. In simulations based on refugee resettlement data using a Bayesian hierarchical model, we find that the algorithm achieves half of the employment gains (relative to the status quo) that could be obtained in an optimal matching based on perfect knowledge of employment probabilities.
Study on antibacterial effect of halicin (SU3327) against Enterococcus faecalis and Enterococcus faecium
Authors: Hussain Zubair , Pengfei She , Yimin Li , Shasha Liu , Zehao Li , Yifan Yang , Linhui Li , Linying Zhou , Yong Wu
Published: September 2022

Enterococci are important pathogens of nosocomial infections and are increasingly difficult to treat due to their intrinsic and acquired resistance to a range of antibiotics. Therefore, there is an urgent need to develop novel antibacterial agents, while drug repurposing is a promising approach to address this issue. Our study aimed to determine the antimicrobial efficacy of halicin against enterococci and found that the minimum inhibitory concentrations (MIC) of halicin against different strains of Enterococcus faecalis and Enterococcus faecium ranged from 4 to 8 μg/ml. In addition, the synergistic antibacterial effect between halicin and doxycycline (DOX) against Enterococcus was observed through the checkerboard method, and it was observed that halicin and DOX could significantly synergistically inhibit biofilm formation and eradicate preformed biofilms at sub-MICs. Moreover, the electron microscope results revealed that halicin could also disrupt the bacterial cell membrane at high concentrations. Furthermore, it is also confirmed that the combination of halicin and DOX has no significant cytotoxic effect on erythrocytes and other human-derived cells. In addition, the mouse subcutaneous model and H&E staining showed that the combination of halicin and DOX could effectively reduce the bacterial load and inflammatory infiltration without obvious side effects. In nutshell, these results demonstrate the potential of halicin in combination with DOX as a novel therapy against infections by Enterococcus.
Lateral Relations in World Politics: Rethinking Interactions and Change among Fields, Systems, and Sectors
Authors: Peña Alejandro M , Davies Thomas
Published: September 2022

Scholarship drawing from a wide array of perspectives including field theoretical and functional differentiation approaches has shed increasing light on the sectoral dimensions of world politics. In contrast to dominant approaches emphasizing hierarchy and power in relations between global fields, this article offers a novel interpretive framework for understanding how diverse fields, systems, or sectors may interact and facilitate change in world politics beyond the operation of established hierarchies and power dynamics. Taking forward the previously underutilized concept of symbolically generalized media of communication, this article elucidates two processes of international political change by which different fields, systems, or sectors may transform world politics. The first process, lateral retreat, is illustrated with reference to the case study of the Protestant Reformation, in which internal changes in the religious field facilitated the development of an increasingly autonomous political domain. The second process, lateral penetration, is illustrated with reference to the international political response to the climate change and Covid-19 crises, in which the scientific sector contributed toward transformed political priorities and associated hierarchies, at least in the short term. These diverse cases are used to indicate the broad potential scope of application of the concept of symbolically generalized media of communication to enrich relational theorizing in the study of international relations, and to improve understanding of diverse dynamics of international political change missed in traditional power- (and anarchy-) centric accounts.
What's in a Norm? Centering the Study of Moral Values in Scholarship on Norm Interactions
Authors: Quissell Kathryn
Published: September 2022

Some norms go through long contested periods, resulting in norm change, rejection, or persisting conflict. Others are adopted quite quickly, with little resistance across diverse societies. An underlying and unanswered theoretical question is why? A foundational characteristic of a norm as a concept, and a key aspect of constructivist scholarship on norms, is the role of values and moral principles in giving norms meaning and in motivating global policy change. For a field placing significant emphasis on the importance of ideas, the limited theorizing around the value-based content of these ideas is a notable shortcoming. Emphasizing the importance of moral values as among the most deeply held beliefs, I outline a theory of how moral values and moral distance can help explain why certain normative processes and outcomes occur. Building from constructivist work on norms and social psychology scholarship on morality, I propose that moral distance, the degree of alignment, overlap, or separation in moral values between actors can help to explain the type of contestation, the intensity and duration of contestation, and what processes or outcomes are more likely to transpire. The shorter the moral distance, the more likely persuasion or adaptations will occur, leading to the eventual adoption of a norm. The greater the moral distance, the more likely prolonged and heated contestation will occur, leading to rejection or enduring contestation. I argue that centering the analysis of moral values and moral distance in research on normative agreement and disagreement can therefore contribute to understanding why or under what circumstances conflict is more or less likely to happen.
Apps for Covid-19 in Germany: assessment using the German Mobile App Rating Scale
Authors: Holl Felix , Flemisch Fabian , Swoboda Walter , Schobel Johannes
Published: September 2022

Objective

The purpose of this study is to provide an overview of apps to help control the spread of Covid-19 in Germany and rate them according to standardized instruments.

Materials and methods

The Apple App Store and Google Play Store were systematically searched to identify apps dealing with Covid-19 in Germany. The German Mobile App Rating Scale (MARS-G) was used to independently assess app quality by 2 trained reviewers.

Results

Overall, the quality of the 6 rated apps was good with a mean score of 4.15 (3.88–4.34). The best-rated apps were NINA app (4.34) and Corona Health App (4.29). The best-rated sections were functionality (4.40), aesthetic (4.25), and information (4.25). In contrast, the worst-rated section was engagement (3.63). Even though some of the apps were used by more people than others, there was no correlation between the MARS-G rating and app store rating. In addition, the MARS-G proved to be effective even with rating apps, which have different goals and methods to achieve them.

Conclusions

To our knowledge, this is the first study that identified and evaluated German Covid-19 mobile health apps available in the German app stores. The review shows that despite the excellent quality in aspects like information and functionality, there is still a gap in the engagement section. To motivate more people to use the Covid-19 apps, new ideas are needed, besides more information and education about the functionality of the apps, to gain trust in app developers and raise the number of downloads.
Molecular Identification of Newly Recorded Louse Columbicola tschulyschman Eichler (Phthiraptera: Philopteridae) From Saudi Arabia With a Note on Genus Columbicola spp. Phylogeny
Authors: Alotaibi Noura J , Al-Turaiki Isra M , Alajmi Reem , Fouzi Boulkenafet , Amjad Bashir Muhammad , Almusawi Zainab , Metwally Dina M , Alzarzor Alajami Mais A , Alajmi Fatemah E , Nasser Mohamed G
Published: September 2022

Chewing lice comprise a large group of ectoparasites that colonize and adversely affect several domestic and wild birds including pigeons. In Saudi Arabia, there is a lack of studies describing such ectoparasites and their infestation rates. Through this work, a new record, Columbicola, tschulyschman Eichler (C. tschulyschman Eichler) was collected from domestic pigeons (Columba livia domestica, Linnaeus). The collected C. tschulyschman Eichler was morphologically identified based on specific taxonomic keys. Mitochondrial (COI) and nuclear (EF-1α) gene fragments were used for molecular identification and phylogenetic reconstruction. In this study, the C. tschulyschman Eichler accounted for around 69.40%. To our knowledge, this is the first report of C. tschulyschman Eichler in Riyadh, Saudi Arabia. To improve the tree topology and differentiate between genera, further studies should utilize the 16s rRNA.
Standard Terms
Authors: Schwenzer Ingeborg , Muñoz Edgardo
Published: September 2022

This chapter expounds on the standard terms. The notion of ‘standard terms’ has traditionally focused on the intention of using pre-drafted terms for an indefinite number of contracts of a certain nature. The matter also implies how these terms have not been individually negotiated. The main purposes of standard terms have been to facilitate the negotiation and performance of the contract and allocate contractual risks to the benefit of the party introducing the respective standard terms. However, modern contract types do not abide by these traditional rules. The chapter then notes the specific rules and incorporation of standard terms. It mentions the significance of transparency as well.
Pre-Contractual Liability
Authors: Schwenzer Ingeborg , Muñoz Edgardo
Published: September 2022

This chapter focuses on the basis of pre-contractual liability. Violating parties’ pre-contractual duties may give rise to liability for damages. There are three possibilities to classify such as contractual by nature, from tort law, or being in an independent category. The practical relevance of determining the dogmatic basis for liability of pre-contractual duties becomes apparent concerning legal systems that display marked differences between contract and tort laws. The chapter notes how comparative analysis reveals how the extent of liability, in general, depends on the scope of the breached pre-contractual duty. It mentions the possibility of loss in line with pre-contractual liability.
Conformity of the Goods
Authors: Schwenzer Ingeborg , Muñoz Edgardo
Published: September 2022

This chapter expounds on the conformity of goods. The distinction between cases of non-conformity and cases of non-delivery is of great practical importance as all legal consequences differ depending on the classification of the case. It highlights the contractual requirements wherein quantity, quality, nature, description, and packaging are considered. Additionally, the chapter notes the domestic approach and uniform approach used to tackle immaterial discrepancies. It also includes the burden of proof in the hands of the seller. All legal systems recognize that the knowledge of the buyer to any purported non-conformity given significance is in line with the seller’s liability.
Avoidance
Authors: Schwenzer Ingeborg , Muñoz Edgardo
Published: September 2022

This chapter notes the notion of avoidance, which represents the most severe interference with the contractual relationship established between the parties. The conceptual guidelines of the CISG are used to remedy the avoidance of contracts. The ambiguity of the term ‘avoidance’ also pervades at the international level. The grounds for avoidance vary from impossibility, delay, non-conformity, and legal defects. The chapter covers the extent of the Nachfrist approach and Fundamental Breach approach. It clarifies the difference between avoidance and rescission as well. Moreover, exercising the right to avoid the contract might result in the impossibility to make restitution.
Veteran Postpartum Health: VA Care Team Perspectives on Care Coordination, Health Equity, and Trauma-Informed Care
Authors: Gopisetty Deepti Divya , Shaw Jonathan G , Gray Caroline , Frayne Susan , Phibbs Ciaran , Shankar Megha
Published: September 2022

Introduction

A growing number of veterans are having children, and pregnancy is an opportunity to engage with health care. Within the Veterans Health Administration (VA), the VA maternity care coordination program supports veterans before, during, and after pregnancy, which are periods that inherently involve transitions between clinicians and risk care fragmentation. Postpartum transitions in care are known to be especially tenuous, with low rates of primary care reengagement. The objective of this study is to better understand this transition from the perspectives of the VA care teams.

Materials and Methods

Eight semi-structured qualitative interviews with VA team members who work in maternity care were conducted at a single VA center’s regional network. Interviews explored the transition from maternity care to primary care to understand the care team’s perspective at three levels: patient, clinician, and systems. Rapid qualitative analysis was used to identify emergent themes.

Results

Participants identified facilitators and opportunities for improvement in the postpartum transition of care. Patient–clinician trust is a key facilitator in the transition from maternity to primary care for veterans, and the breadth of VA services emerged as a key system-level facilitator to success. Interviewees also highlighted opportunities for improvement, including more trauma-informed practices for nonbinary veterans, increased care coordination between VA and community staff, and the need for training in postpartum health with an emphasis on health equity for primary care clinicians.

Conclusions

The Department of Veterans Affairs Healthcare System care team perspectives may inform practice changes to support the transition from maternity to primary care for veterans. To move toward health equity, a system-level approach to policy and programming is necessary to reduce barriers to primary care reengagement. This study was limited in terms of sample size, and future research should explore veteran perspectives on VA postpartum care transitions.
Towards solar measurements of nuclear reaction rates
Authors: Bellinger Earl Patrick , Christensen-Dalsgaard Jørgen
Published: September 2022

Nuclear reaction rates are a fundamental yet uncertain ingredient in stellar evolution models. The astrophysical S-factor pertaining to the initial reaction in the proton–proton (pp) chain is uncertain at the 1 per cent level, which contributes a systematic but generally unpropagated error of similar order in the theoretical ages of stars. In this work, we study the prospect of improving the measurement of this and other reaction rates in the pp chain and CNO cycle using helioseismology and solar neutrinos. We show that when other aspects of the solar model are improved, then it shall be possible using current solar data to improve the precision of this measurement by nearly an order of magnitude and hence the corresponding uncertainty on the ages of low-mass stars by a similar amount.
Dwarf AGNs from variability for the origins of seeds (DAVOS): Intermediate-mass black hole demographics from optical synoptic surveys
Authors: Burke Colin J , Shen Yue , Liu Xin , Natarajan Priyamvada , Caplar Neven , Bellovary Jillian M , Wang Z Franklin
Published: September 2022

We present a phenomenological forward Monte Carlo model for forecasting the population of active galactic nuclei (AGNs) in dwarf galaxies observable via their optical variability. Our model accounts for expected changes in the spectral energy distribution of AGNs in the intermediate-mass black hole (IMBH) mass range and uses observational constraints on optical variability as a function of black hole (BH) mass to generate mock light curves. Adopting several different models for the BH occupation function, including one for off-nuclear IMBHs, we quantify differences in the predicted local AGN mass and luminosity functions in dwarf galaxies. As a result, we are able to model the fraction of variable AGNs as a function of important galaxy host properties, such as host galaxy stellar mass, in the presence of selection effects. We find that our adopted occupation fractions for the ‘heavy’ and ‘light’ initial BH seeding scenarios can be distinguished with variability at the 2–3σ level for galaxy host stellar masses below ∼108M⊙ with data from the upcoming Vera C. Rubin Observatory. We also demonstrate the prevalence of a selection bias whereby recovered IMBH masses fall, on average, above the predicted value from the local host galaxy–BH mass scaling relation with the strength of this bias dependent on the survey sensitivity. Our methodology can be used more broadly to calibrate AGN demographic studies in synoptic surveys. Finally, we show that a targeted ∼ hourly cadence program over a few nights with the Rubin Observatory can provide strong constraints on IMBH masses given their expected rapid variability time-scales.
The Cosmic Ultraviolet Baryon Survey (CUBS) V: on the thermodynamic properties of the cool circumgalactic medium at z ≲ 1
Authors: Qu Zhijie , Chen Hsiao-Wen , Rudie Gwen C , Zahedy Fakhri S , Johnson Sean D , Boettcher Erin , Cantalupo Sebastiano , Chen Mandy C , Cooksey Kathy L , DePalma David , Faucher-Giguère Claude-André , Rauch Michael , Schaye Joop , Simcoe Robert A
Published: September 2022

This paper presents a systematic study of the photoionization and thermodynamic properties of the cool circumgalactic medium (CGM) as traced by rest-frame ultraviolet absorption lines around 26 galaxies at redshift z ≲ 1. The study utilizes both high-quality far-ultraviolet and optical spectra of background QSOs and deep galaxy redshift surveys to characterize the gas density, temperature, and pressure of individual absorbing components and to resolve their internal non-thermal motions. The derived gas density spans more than three decades, from $\log (n_{\rm H}/{{\rm cm^{-3}}}) \approx -4$ to −1, while the temperature of the gas is confined in a narrow range of log (T/K) ≈ 4.3 ± 0.3. In addition, a weak anticorrelation between gas density and temperature is observed, consistent with the expectation of the gas being in photoionization equilibrium. Furthermore, decomposing the observed line widths into thermal and non-thermal contributions reveals that more than 30 per cent of the components at z ≲ 1 exhibit line widths driven by non-thermal motions, in comparison to <20 per cent found at z ≈ 2–3. Attributing the observed non-thermal line widths to intra-clump turbulence, we find that massive quenched galaxies on average exhibit higher non-thermal broadening/turbulent energy in their CGM compared to star-forming galaxies at z ≲ 1. Finally, strong absorption features from multiple ions covering a wide range of ionization energy (e.g. from Mg ii to O iv) can be present simultaneously in a single absorption system with kinematically aligned component structure, but the inferred pressure in different phases may differ by a factor of ≈10.
Double detonations: variations in Type Ia supernovae due to different core and He shell masses – II. Synthetic observables
Authors: Collins Christine E , Gronow Sabrina , Sim Stuart A , Röpke Friedrich K
Published: September 2022

Double detonations of sub-Chandrasekhar mass white dwarfs are a promising explosion scenario for Type Ia supernovae, whereby a detonation in a surface helium shell triggers a secondary detonation in a carbon-oxygen core. Recent work has shown that low-mass helium shell models reproduce observations of normal SNe Ia. We present 3D radiative transfer simulations for a suite of 3D simulations of the double detonation explosion scenario for a range of shell and core masses. We find light curves broadly able to reproduce the faint end of the width–luminosity relation shown by SNe Ia, however, we find that all of our models show extremely red colours, not observed in normal SNe Ia. This includes our lowest mass helium shell model. We find clear Ti ii absorption features in the model spectra, which would lead to classification as peculiar SNe Ia, as well as line blanketing in some lines of sight by singly ionized Cr and Fe-peak elements. Our radiative transfer simulations show that these explosion models remain promising to explain peculiar SNe Ia. Future full non-LTE simulations may improve the agreement of these explosion models with observations of normal SNe Ia.
Dipolar dark matter simulations on galaxy scales with the ramses code
Authors: Stahl Clément , Famaey Benoit , Thomas Guillaume , Dubois Yohan , Ibata Rodrigo
Published: September 2022

We numerically explore on galaxy scales the dipolar dark matter (DM) model based on the concept of gravitational polarization. This DM model has been proposed as a natural way to reproduce observed tight galactic scaling relations such as the baryonic Tully–Fisher relation and the Radial Acceleration Relation. We present a customized version of the RAMSES code including for the first time the dynamics of this Dipolar DM in N-body simulations. As a first application of this code, we check that we recover an equilibrium configuration that had been found analytically, where a low density Dipolar DM halo is at rest with respect to its central galaxy, recovering the aforementioned scaling relations. A characteristic signature of this equilibrium model is that it harbours a dynamical instability with a characteristic time depending on the Dipolar DM halo density, which we recover numerically. This represents a first step towards more involved simulations needed to test this framework, ranging from galaxy interactions to structure formation.
The nuclear transient AT 2017gge: a tidal disruption event in a dusty and gas-rich environment and the awakening of a dormant SMBH
Authors: Onori F , Cannizzaro G , Jonker P G , Kim M , Nicholl M , Mattila S , Reynolds T M , Fraser M , Wevers T , Brocato E , Anderson J P , Carini R , Charalampopoulos P , Clark P , Gromadzki M , Gutiérrez C P , Ihanec N , Inserra C , Lawrence A , Leloudas G , Lundqvist P , Müller-Bravo T E , Piranomonte S , Pursiainen M , Rybicki K A , Somero A , Young D R , Chambers K C , Gao H , de Boer T J L , Magnier E A
Published: September 2022

We present the results from a dense multwavelength [optical/UV, near-infrared (IR), and X-ray] follow-up campaign of the nuclear transient AT 2017gge, covering a total of 1698 d from the transient’s discovery. The bolometric light curve, the blackbody temperature and radius, the broad H and He i λ5876 emission lines and their evolution with time, are all consistent with a tidal disruption event (TDE) nature. A soft X-ray flare is detected with a delay of ∼200 d with respect to the optical/UV peak and it is rapidly followed by the emergence of a broad He ii λ4686 and by a number of long-lasting high ionization coronal emission lines. This indicate a clear connection between a TDE flare and the appearance of extreme coronal line emission (ECLEs). An IR echo, resulting from dust re-radiation of the optical/UV TDE light is observed after the X-ray flare and the associated near-IR spectra show a transient broad feature in correspondence of the He i λ10830 and, for the first time in a TDE, a transient high-ionization coronal NIR line (the [Fe xiii] λ10798) is also detected. The data are well explained by a scenario in which a TDE occurs in a gas-and-dust rich environment and its optical/UV, soft X-ray, and IR emission have different origins and locations. The optical emission may be produced by stellar debris stream collisions prior to the accretion disc formation, which is instead responsible for the soft X-ray flare, emitted after the end of the circularization process.
Controlling outlier contamination in multimessenger time-domain searches for supermasssive binary black holes
Authors: Wang Qiaohong , Taylor Stephen R
Published: September 2022

Time-domain data sets of many varieties can be prone to statistical outliers that result from instrumental or astrophysical anomalies. These can impair searches for signals within the time series and lead to biased parameter estimation. Versatile outlier mitigation methods tuned toward multimessenger time-domain searches for supermassive binary black holes have yet to be fully explored. In an effort to perform robust outlier isolation with low computational costs, we propose a Gibbs sampling scheme. This provides structural simplicity to outlier modelling and isolation, as it requires minimal modifications to adapt to time-domain modelling scenarios with pulsar-timing array or photometric data. We robustly diagnose outliers present in simulated pulsar-timing data sets, and then further apply our methods to pulsar J1909−3744 from the NANOGrav 9-year Data set. We also explore the periodic binary-AGN candidate PG1302−102 using data sets from the Catalina Real-time Transient Survey, All-Sky Automated Survey for Supernovae, and the Lincoln Near-Earth Asteroid Research. We present our findings and outline future work that could improve outlier modelling and isolation for multimessenger time-domain searches.
ASymba: H i global profile asymmetries in the simba simulation
Authors: Glowacki M , Deg N , Blyth S-L , Hank N , Davé R , Elson E , Spekkens K
Published: September 2022

Asymmetry in the spatially integrated, 1D H i global profiles of galaxies can inform us on both internal (e.g. outflows) and external (e.g. mergers, tidal interactions, and ram pressure stripping) processes that shape galaxy evolution. Understanding which of these primarily drive H i profile asymmetry is of particular interest. In the lead-up to SKA pathfinder and SKA H i emission surveys, hydrodynamical simulations have proved to be a useful resource for such studies. Here, we present the methodology behind, as well as first results, of ASymba: Asymmetries in H i of Simba galaxies, the first time this simulation suite has been used for this type of study. We generate mock observations of the H i content of these galaxies and calculate the profile asymmetries using three different methods. We find that $M_{\rm H\, {\small I}}$ has the strongest correlation with all asymmetry measures, with weaker correlations also found with the number of mergers a galaxy has undergone, and gas and galaxy rotation. We also find good agreement with the xGASS sample, in which galaxies with highly asymmetric profiles tend to have lower H i gas fractions than galaxies with symmetric profiles, and additionally find the same holds in sSFR parameter space. For low H i mass galaxies, it is difficult to distinguish between asymmetric and symmetric galaxies, but this becomes achievable in the high H i mass population. These results showcase the potential of ASymba and provide the groundwork for further studies, including comparison to upcoming large H i emission surveys.
A gravitational and dynamical framework of star formation: the Orion nebula
Authors: Kounkel Marina , Stassun Keivan G , Covey Kevin , Hartmann Lee
Published: September 2022

The Orion Nebula Cluster (ONC) is the most massive region of active star formation within a kpc of the Sun. Using Gaia DR3 parallaxes and proper motions, we examine the bulk motions of stars radially and tangentially relative to the cluster centre. We find an age gradient with distance to the stars in the ONC, from 385 pc for the oldest stars, to 395 pc for the younger stars, indicating that the star-forming front is propagating into the cloud. We find an organized signature of rotation of the central cluster, but it is present only in stars younger than 2 Myr. We also observe a net infall of young stars into the centre of the ONC’s deep gravitational potential well. The infalling sources lie preferentially along the filament; on the other hand, outflowing sources are distributed spherically around the cluster, and they have larger velocity dispersion. We further propose a solution to a long-standing question of why the ONC shows a weak signature of expansion even though the cluster is likely bound: much of this expansion may be driven by unstable N-body interactions among stars, resulting in low-velocity ejections. Though analysing signatures imprinted on stellar dynamics across different spatial scales, these observation shed new light on the signatures of formation and evolution of young clusters.
Electron attachment to interstellar grains
Authors: Flower D R
Published: September 2022

We have performed quantum mechanical calculations of cross-sections and rate coefficients for electron attachment to small, neutral, and positively charged grains. In addition to the polarization potential and – for charged grains – the Coulomb potential, we considered the influence of the interaction between the charge of the electron and a possible permanent electric dipole on the grain. We found large discrepancies between the predictions of classical and quantal models of electron scattering on neutral grains at low energies (temperatures) in the absence of a permanent dipole moment, but much closer agreement when a dipole moment was present. The presence of the long-range Coulomb potential also leads to better agreement between classical and quantal models.
Infrared radiation feedback does not regulate star cluster formation
Authors: Menon Shyam H , Federrath Christoph , Krumholz Mark R
Published: September 2022

We present 3D radiation-hydrodynamical (RHD) simulations of star cluster formation and evolution in massive, self-gravitating clouds, whose dust columns are optically thick to infrared (IR) photons. We use VETTAM – a recently developed, novel RHD algorithm, which uses the Variable Eddington Tensor closure – to model the IR radiation transport through the cloud. We also use realistic temperature (T) dependent IR opacities (κ) in our simulations, improving upon earlier works in this area, which used either constant IR opacities or simplified power laws (κ ∝ T2). We investigate the impact of the radiation pressure of these IR photons on the star formation efficiency of the cloud, and its potential to drive dusty winds. We find that IR radiation pressure is unable to regulate star formation or prevent accretion on to the star clusters, even for very high gas surface densities ($\Sigma \gt 10^5 \, \mathrm{M}_{\odot } \, \mathrm{pc}^{-2}$), contrary to recent semi-analytic predictions and simulation results using simplified treatments of the dust opacity. We find that the commonly adopted simplifications of κ ∝ T2 or constant κ for the IR dust opacities leads to this discrepancy, as those approximations overestimate the radiation force. By contrast, with realistic opacities that take into account the microphysics of the dust, we find that the impact of IR radiation pressure on star formation is very mild, even at significantly high dust-to-gas ratios (∼3 times solar), suggesting that it is unlikely to be an important feedback mechanism in controlling star formation in the ISM.
Stability of axially symmetric magnetic fields in stars
Authors: Becerra Laura , Reisenegger Andreas , Valdivia Juan Alejandro , Gusakov Mikhail
Published: September 2022

The magnetic fields observed in Ap stars, white dwarfs, and neutron stars are known to be stable for long times. However, the physical conditions inside the stellar interiors that allow these states are still a matter of research. It has been formally demonstrated that both purely toroidal and purely poloidal magnetic fields develop instabilities at some point in the star. On the other hand, numerical simulations have proved the stability of roughly axisymmetric magnetic field configurations inside stably stratified stars. These configurations consist of mutually stabilizing toroidal and poloidal components in a twisted torus shape. Previous studies have proposed rough upper and lower bounds on the ratio of the magnetic energy in the toroidal and poloidal components of the magnetic field. With the purpose of mapping out the parameter space under which such configurations remain stable, we used the Pencil Code to perform 3D magnetohydrodynamic simulations of the evolution of the magnetic field in non-rotating, non-degenerate stars in which viscosity is the only dissipation mechanism, both for stars with a uniform (barotropic) and radially increasing (stably stratified) specific entropy. Furthermore, we considered different conditions regarding the degree of stable stratification and the magnetic energy in each component, roughly confirming the previously suggested stability boundaries for the magnetic field.
7Be detection in the 2021 outburst of RS Oph
Authors: Molaro P , Izzo L , Selvelli P , Bonifacio P , Aydi E , Cescutti G , Guido E , Harvey E J , Hernanz M , Della Valle M
Published: September 2022

The recurrent nova RS Oph underwent a new outburst on 2021 August 8, reaching a visible brightness of V = 4.8 mag. Observations of the 2021 outburst made with the high-resolution UVES spectrograph at the Kueyen-UT2 telescope at ESO-VLT in Paranal enabled detection of the possible presence of 7Be newly made in the thermonuclear runaway reactions. The 7Be yields can be estimated at N(7Be)/N(H)  = 5.7 × 10−6, which are close to the lowest yields measured in classical novae so far. 7Be is short-lived and decays only into 7Li. By means of a spectrum taken during the nebular phase we estimated an ejected mass of ≈ 1.1 × 10−5 M⊙, providing an amount of ≈ 4.4 × 10−10 M⊙ of 7Li created in the 2021 event. Recurrent novae of the RS Oph type may synthesize slightly lower amounts of 7Li per event than classical novae, but occur 103 times more frequently. The recurrent novae fraction is in the range of 10–30 per cent and they could have contributed to the making of the 7Li that we observe today. The detection of 7Be in RS Oph provides further support to the recent suggestion that novae are the most effective source of 7Li in the Galaxy.
The imprint of gas on gravitational waves from LISA intermediate-mass black hole binaries
Authors: Garg Mudit , Derdzinski Andrea , Zwick Lorenz , Capelo Pedro R , Mayer Lucio
Published: September 2022

We study the effect of torques on circular inspirals of intermediate-mass black hole binaries (IMBHBs) embedded in gas discs, wherein both BH masses are in the range 102–105 M⊙, up to redshift z = 10. We focus on how torques impact the detected gravitational wave (GW) waveform in the LISA frequency band when the binary separation is within a few hundred Schwarzschild radii. For a sub-Eddington accretion disc with a viscosity coefficient α = 0.01, surface density Σ ≈ 105 g cm−2, and Mach number $\mathcal {M}_{\rm {a}}\approx 80$, a gap, or a cavity, opens when the binary is in the LISA band. Depending on the torque’s strength, LISA will observe dephasing in the IMBHB’s GW signal up to either z ∼ 5 for high mass ratios (q ≈ 0.1) or to z ∼ 7 for q ≈ 10−3. We study the dependence of the measurable dephasing on variations of BH masses, redshift, and accretion rates. Our results suggest that phase shift is detectable even in high-redshift (z = 10) binaries if they experience super-Eddington accretion episodes. We investigate if the disc-driven torques can result in an observable ‘time-dependent’ chirp mass with a simplified Fisher formalism, finding that, at the expected signal-to-noise ratio, the gas-induced variation of the chirp mass is too small to be detected. This work shows how gas-induced perturbations of vacuum waveforms should be strong enough to be detected by LISA for the IMBHB in the early inspiral phase. These perturbations encode precious information on accretion discs and galactic nuclei astrophysics. High-accuracy waveform models which incorporate these effects will be needed to extract such information.
SWIFT J0503.7-2819: a nearly synchronous intermediate polar below the period gap?
Authors: Rawat Nikita , Pandey J C , Joshi Arti , Scaringi Simone , Yadava Umesh
Published: September 2022

Based on the X-ray observations from XMM–Newton and Swift, and optical observations from Transiting Exoplanet Survey Satellite (TESS) and AAVSO, we present temporal and spectral properties of probable intermediate polar SWIFT J0503.7-2819. The X-ray light curve shows two distinctive features, where possibly the second pole seems to be active during the middle of the XMM–Newton observations. Present analysis confirms and also refines the previously reported orbital period of SWIFT J0503.7-2819 as 81.65 ± 0.04 min. The X-ray and optical variations of this target have been found to occur at the period of ∼65 min, which we propose as the spin period of the white dwarf. The energy-dependent modulation at this period, which are due to the photoelectric absorption in the accretion flow, also assures this conjecture. Two-temperature thermal plasma model well explains the X-ray spectra with temperatures of ∼150 eV and ∼18.5 keV, which is absorbed by a dense material with an average equivalent hydrogen column density of 3.8 × 1022 cm−2 that partially covers ∼27 per cent of the X-ray source. An attempt is made to understand the accretion flow in this system using the present data of SWIFT J0503.7-2819. If the proposed spin period is indeed the actual period, then SWIFT J0503.7-2819 could be the first nearly synchronous intermediate polar below the period gap.
tidy tree: A New Layout for Phylogenetic Trees
Authors: Penel Simon , de Vienne Damien M
Published: September 2022

Many layouts exist for visualizing phylogenetic trees, allowing to display the same information (evolutionary relationships) in different ways. For large phylogenies, the choice of the layout is a key element, because the printable area is limited, and because interactive on-screen visualizers can lead to unreadable phylogenetic relationships at high zoom levels. A visual inspection of available layouts for rooted trees reveals large empty areas that one may want to fill in order to use less drawing space and eventually gain readability. This can be achieved by using the nonlayered tidy tree layout algorithm that was proposed earlier but was never used in a phylogenetic context so far. Here, we present its implementation, and we demonstrate its advantages on simulated and biological data (the measles virus phylogeny). Our results call for the integration of this new layout in phylogenetic software. We implemented the nonlayered tidy tree layout in R language as a stand-alone function (available at https://github.com/damiendevienne/non-layered-tidy-trees), as an option in the tree plotting function of the R package ape, and in the recent tool for visualizing reconciled phylogenetic trees thirdkind (https://github.com/simonpenel/thirdkind/wiki).
Recurrent but Short-Lived Duplications of Centromeric Proteins in HolocentricCaenorhabditisSpecies
Authors: Caro Lews , Raman Pravrutha , Steiner Florian A , Ailion Michael , Malik Harmit S
Published: September 2022

Centromeric histones (CenH3s) are essential for chromosome inheritance during cell division in most eukaryotes. CenH3 genes have rapidly evolved and undergone repeated gene duplications and diversification in many plant and animal species. In Caenorhabditis species, two independent duplications of CenH3 (named hcp-3 for HoloCentric chromosome-binding Protein 3) were previously identified in C. elegans and C. remanei. Using phylogenomic analyses in 32 Caenorhabditis species, we find strict retention of the ancestral hcp-3 gene and 10 independent duplications. Most hcp-3L (hcp-3-like) paralogs are only found in 1–2 species, are expressed in both males and females/hermaphrodites, and encode histone fold domains with 69–100% identity to ancestral hcp-3. We identified novel N-terminal protein motifs, including putative kinetochore protein-interacting motifs and a potential separase cleavage site, which are well conserved across Caenorhabditis HCP-3 proteins. Other N-terminal motifs vary in their retention across paralogs or species, revealing potential subfunctionalization or functional loss following duplication. An N-terminal extension in the hcp-3L gene of C. afra revealed an unprecedented protein fusion, where hcp-3L fused to duplicated segments from hcp-4 (nematode CENP-C). By extending our analyses beyond CenH3, we found gene duplications of six inner and outer kinetochore genes in Caenorhabditis, which appear to have been retained independent of hcp-3 duplications. Our findings suggest that centromeric protein duplications occur frequently in Caenorhabditis nematodes, are selectively retained for short evolutionary periods, then degenerate or are lost entirely. We hypothesize that unique challenges associated with holocentricity in Caenorhabditis may lead to this rapid “revolving door” of kinetochore protein paralogs.
A massively parallel reporter assay reveals focused and broadly encoded RNA localization signals in neurons
Authors: Mikl Martin , Eletto Davide , Nijim Malak , Lee Minkyoung , Lafzi Atefeh , Mhamedi Farah , David Orit , Sain Simona Baghai , Handler Kristina , Moor Andreas E
Published: September 2022

Asymmetric subcellular mRNA localization allows spatial regulation of gene expression and functional compartmentalization. In neurons, localization of specific mRNAs to neurites is essential for cellular functioning. However, it is largely unknown how transcript sorting works in a sequence-specific manner. Here, we combined subcellular transcriptomics and massively parallel reporter assays and tested ∼50 000 sequences for their ability to localize to neurites. Mapping the localization potential of >300 genes revealed two ways neurite targeting can be achieved: focused localization motifs and broadly encoded localization potential. We characterized the interplay between RNA stability and localization and identified motifs able to bias localization towards neurite or soma as well as the trans-acting factors required for their action. Based on our data, we devised machine learning models that were able to predict the localization behavior of novel reporter sequences. Testing this predictor on native mRNA sequencing data showed good agreement between predicted and observed localization potential, suggesting that the rules uncovered by our MPRA also apply to the localization of native full-length transcripts.
Sampling via the aggregation value for data-driven manufacturing
Authors: Liu Xu , Chen Gengxiang , Li Yingguang , Chen Lu , Meng Qinglu , Mehdi-Souzani Charyar
Published: September 2022

Data-driven modelling has shown promising potential in many industrial applications, while the expensive and time-consuming labelling of experimental and simulation data restricts its further development. Preparing a more informative but smaller dataset to reduce labelling efforts has been a vital research problem. Although existing techniques can assess the value of individual data samples, how to represent the value of a sample set remains an open problem. In this research, the aggregation value is defined using a novel representation for the value of a sample set by modelling the invisible redundant information as the overlaps of neighbouring values. The sampling problem is hence converted to the maximisation of the submodular function over the aggregation value. The comprehensive analysis of several manufacturing datasets demonstrates that the proposed method can provide sample sets with superior and stable performance compared with state-of-the-art methods. The research outcome also indicates its appealing potential to reduce labelling efforts for more data-scarcity scenarios.
The Alteration of Tomato Chloroplast Vesiculation Positively Affects Whole-Plant Source–Sink Relations and Fruit Metabolism under Stress Conditions
Authors: Ahouvi Yoav , Haber Zechariah , Zach Yair Yehoshua , Rosental Leah , Toubiana David , Sharma Davinder , Alseekh Saleh , Tajima Hiromi , Fernie Alisdair R , Brotman Yariv , Blumwald Eduardo , Sade Nir
Published: September 2022

Changes in climate conditions can negatively affect the productivity of crop plants. They can induce chloroplast degradation (senescence), which leads to decreased source capacity, as well as decreased whole-plant carbon/nitrogen assimilation and allocation. The importance, contribution and mechanisms of action regulating source-tissue capacity under stress conditions in tomato (Solanum lycopersicum) are not well understood. We hypothesized that delaying chloroplast degradation by altering the activity of the tomato chloroplast vesiculation (CV) under stress would lead to more efficient use of carbon and nitrogen and to higher yields. Tomato CV is upregulated under stress conditions. Specific induction of CV in leaves at the fruit development stage resulted in stress-induced senescence and negatively affected fruit yield, without any positive effects on fruit quality. Clustered Regularly Interspaced Short Palindromic Repeats/CRISPR-associated protein 9 (CRISPR/CAS9) knockout CV plants, generated using a near-isogenic tomato line with enhanced sink capacity, exhibited stress tolerance at both the vegetative and the reproductive stages, leading to enhanced fruit quantity, quality and harvest index. Detailed metabolic and transcriptomic network analysis of sink tissue revealed that the l-glutamine and l-arginine biosynthesis pathways are associated with stress-response conditions and also identified putative novel genes involved in tomato fruit quality under stress. Our results are the first to demonstrate the feasibility of delayed stress-induced senescence as a stress-tolerance trait in a fleshy fruit crop, to highlight the involvement of the CV pathway in the regulation of source strength under stress and to identify genes and metabolic pathways involved in increased tomato sink capacity under stress conditions.
Synergistic chemo-/photothermal therapy based on supercritical technology-assisted chitosan–indocyanine green/luteolin nanocomposites for wound healing
Authors: Xu Pei-Yao , Kankala Ranjith Kumar , Li Yue-Wei , Wang Shi-Bin , Chen Ai-Zheng
Published: September 2022

Despite the success, it is highly challenging to battle against pathogenic biofilms-based chronic bacterial infections by conventional antibiotic therapy. Herein, we report a near-infrared (NIR)/acid-induced nanoplatform based on chitosan (CS)-coated indocyanine green (ICG, photosensitizer)/luteolin (LUT, a natural quorum sensing inhibitor) nanocomposites (ICG/LUT-CS) as antibacterial and antibiofilm agents for skin wound healing. Initially, the ICG/LUT nanoplatforms are prepared by the supercritical antisolvent technology and coated with the CS layer. The obtained ICG/LUT-CS with ultra-high encapsulation efficiency exhibited more favorable photothermal conversion effects and improved NIR laser/acid dual-induced drug release behavior than individual modalities, achieving exceptional bacteria-killing and biofilm elimination effects. Moreover, the ICG/LUT-CS realized the synergetic effects of chemotherapy and photothermal therapy outcomes for wound healing. Together, our findings provided an appealing strategy for the rapid preparation and future translational application of ICG/LUT-CS as an ideal agent for fighting against biofilm infections.