bluuebunny/crossref_metadata_2025 huggingface dataset:
Sperm physiology and in vitro fertilising ability rely on basal metabolic activity: insights from the pig model
Authors: Mateo-Otero Yentel , Madrid-Gambin Francisco , Llavanera Marc , Gomez-Gomez Alex , Haro Noemí , Pozo Oscar J. , Yeste Marc
Published: March 2023

Whether basal metabolic activity in sperm has any influence on their fertilising capacity has not been explored. Using the pig as a model, the present study investigated the relationship of energetic metabolism with sperm quality and function (assessed through computer-assisted sperm analysis and flow cytometry), and fertility (in vitro fertilisation (IVF) outcomes). In semen samples from 16 boars, levels of metabolites related to glycolysis, ketogenesis and Krebs cycle were determined through a targeted metabolomics approach using liquid chromatography-tandem mass spectrometry. High-quality sperm are associated to greater levels of glycolysis-derived metabolites, and oocyte fertilisation and embryo development are conditioned by the sperm metabolic status. Interestingly, glycolysis appears to be the preferred catabolic pathway of the sperm giving rise to greater percentages of embryos at day 6. In conclusion, this study shows that the basal metabolic activity of sperm influences their function, even beyond fertilisation.
Fluorescence “ON–OFF–ON” response in the formation of a tetrahedral anionocage and encapsulation of halogenated hydrocarbons
Authors: Zhao Jie , Zhang Wenyao , Zheng Yayun , Wang Yue , Yang Dong
Published: March 2023

A three-model fluorescence “ON–OFF–ON” system, from a tris-bis(urea) anion ligand (LMe) to anionocage 1Me and then to the host–guest complex, in response to anion coordination and halogenated hydrocarbon encapsulation, was established.
Improved modeling of anharmonicity for furan microsolvation
Authors: Kopp Wassja A. , Mödden Matthias L. , Viswanathan Narasimhan , Rath Gabriel , Leonhard Kai
Published: March 2023

1D-hindered rotor profiles are corrected for coupled cluster energies at stationary points. Probability density functions at each energy level allow to resolve different conformations within the scan.
Single-bonded nitrogen chain and porous nitrogen layer via Ce–N compounds
Authors: Ding Chi , Yuan Jianan , Wang Xiaomeng , Huang Tianheng , Wang Yunlong , Sun Jian
Published: March 2023

We explored the phase diagram of Ce–N compounds, and identified several interesting poly-nitrogen species, including the infinite helical chain, and porous poly-nitrogen layer.
Compositional gradient engineering and applications in halide perovskites
Authors: Li Junyu , Han Zeyao , Liu Jiaxin , Zou Yousheng , Xu Xiaobao
Published: March 2023

The compositional gradient engineering of halide perovskites is summarized, where carrier extraction can be promoted in optoelectronic devices and the multiple components on one device facilitate multi-spectral detection/emission applications.
Lab free protein-based moisture electric generators with a high electric output
Authors: Zhu Renbo , Zhu Yanzhe , Hu Long , Guan Peiyuan , Su Dawei , Zhang Shuo , Liu Chao , Feng Ziheng , Hu Guangyu , Chen Fandi , Wan Tao , Guan Xinwei , Wu Tom , Joshi Rakesh , Li Mengyao , Cazorla Claudio , Lu Yuerui , Han Zhaojun , Xu Haolan , Chu Dewei
Published: March 2023

Illustration of protein-based MEG generating electricity by absorbing water from moisture.
Asteroseismic age constraints on the open cluster NGC 2477 using oscillating stars identified with TESS FFI
Authors: Palakkatharappil D. B. , Creevey O. L.
Published: March 2023

Context. Asteroseismology is one of the few methods to derive ages of individual stars due to the high precision of their observations. Isochrone fitting is a powerful alternative method for deriving ages by studying clusters of stars. Pulsating stars in clusters should therefore allow for detailed studies of the stellar models.

Aims. Our objectives are to exploit the NASA TESS data along with ESA Gaia data to search for and detect oscillations in cluster member stars. We analyse the intermediate-age open cluster NGC 2477, known to suffer from differential extinction, to explore if asteroseismology and cluster characteristics can help us understand the metallicity and extinction, as well as result in better age determinations than isochrone-fitting alone.

Methods. We combined a multitude of recent observations from Gaia, high-resolution spectroscopy, and extinction maps to analyse the cluster and then search for and detect variability in the member stars using TESS full frame images (FFIs) data. To interpret all of these data, we used stellar structure, evolution and oscillation codes.

Results. We conducted an in-depth analysis of the extinction and metallicity of NGC 2477, using the most recent spectroscopic, photometric, and extinction observations for the cluster. Analysis of dust and extinction maps confirmed that the differential extinction in the direction of the cluster is not due to the background. The cluster’s metallicity from high-resolution spectroscopy varies from 0.06 to 0.16 dex. We performed an isochrone fitting to the cluster using publically available isochrones (BASTI, MIST, and PARSEC), which provides a cluster age of between 0.6 to 1.1 Ga. Then using TESS FFI, we analysed the time dimension of the members of this cluster. We created optimised pixel light curves using the tessipack package which allows us to consider possible contamination by nearby stars. Using these light curves, we identified many interesting levels of variability of stars in this cluster, including binaries and oscillating stars. For the asteroseismic analysis, we selected a few uncontaminated A–F type oscillating stars and used the MESA and GYRE codes to interpret the frequency signals. By comparing the theoretical and the observed spectra, we identified frequency separations, Δν, for four stars. Then using the identified Δν and imposing that the best matched theoretical models have the same age, metallicity, and background extinction, we constrained the cluster’s age to 1.0 ± 0.1 Ga.

Conclusions. We conclude that using the TESS FFI data, we can identify oscillating stars in clusters and constrain the age of the cluster using asteroseismology.
Modification of some scalarization approaches for multiobjective optimization
Authors: Khorasani Vahid Amiri , Khorram Esmaile
Published: March 2023

In this paper, we propose revisions of two existing scalarization approaches, namely the feasible-value constraint and the weighted constraint. These methods do not easily provide results on proper efficient solutions of a general multiobjective optimization problem. By proposing some novel modifications for these methods, we derive some interesting results concerning proper efficient solutions. These scalarization approaches need no convexity assumption of the objective functions. We also demonstrate the efficiency of the proposed method using numerical experiments. In particular, a rocket injector design problem involving four objective functions illustrates the performance of the proposed method.
Biopsy Diagnosis of Hirschsprung's Disease Using a Single Excisional Biopsy Based on the Anorectal Line
Authors: Takeda Masahiro , Ochi Takanori , Koga Hiroyuki , Tsuboi Koichi , Arakawa Atsushi , Lane Geoffrey J. , Yamataka Atsuyuki
Published: March 2023

Introduction A biopsy protocol for diagnosing Hirschsprung's disease (HD) in children using the anorectal line (ARL).

Materials and Methods The ARL was adopted for diagnosing HD in 2016 using two excisional submucosal rectal biopsies performed at different levels, sequentially; the first just above the ARL and the second, further proximal (2-ARL). Currently, only the first-level biopsy is performed (1-ARL) and examined intraoperatively. Management was observation if normoganglionic, pull-through if aganglionic, and a second-level biopsy if hypoganglionic. Hypoganglionosis was considered physiologic if the second-level biopsy was normoganglionic and pathologic if hypoganglionic. Colon caliber change and bowel obstructive symptoms reflect the severity of hypoganglionosis.

Results For 2-ARL (n = 54), results were: normoganglionosis (n = 31/54; 57.4%), aganglionosis (n = 19/54; 35.2%), and hypoganglionosis (n = 4/54; 7.4%); physiologic (n = 3/54; 5.6%) and pathologic (n = 1/54; 1.9%). Normoganglionosis and aganglionosis were always duplicated in 2-ARL (kappa = 1.0). For 1-ARL (n = 36), results were: normoganglionosis (n = 17/36; 47.2%), aganglionosis (n = 17/36; 47.2%), and hypoganglionosis (n = 2/36; 5.6%). Second-level biopsies were normoganglionic (physiologic: n = 1) and hypoganglionic (pathologic: n = 1). All normoganglionic cases, except one, resolved conservatively. All aganglionic cases had pull-through with HD confirmed on histopathology. Both pathologic hypoganglionic cases had caliber change and severe obstructive symptoms as definitive indications for pull-through with hypoganglionosis of the entire rectum confirmed on histopathology. Physiologic hypoganglionic cases were observed and currently have regular defecation.

Conclusion Because the ARL is an objective functional, neurologic, and anatomic demarcation, normoganglionosis and aganglionosis can be diagnosed accurately with a single excisional biopsy. Only hypoganglionosis requires a second-level biopsy.
Effects of the COVID-19 Pandemic on Access to Education and Social Participation in Children and Adolescents with Duchenne Muscular Dystrophy in Switzerland
Authors: Henzi Bettina C. , Baumann Dominique , Erni Sarah J. , Lötscher Nadine , Tscherter Anne , Klein Andrea ,   on behalf of the Swiss-Reg-NMD Group
Published: March 2023

Two-thirds of patients with Duchenne muscular dystrophy (DMD) have cognitive and neuropsychiatric problems. Concerning their quality of life, negative factors are the lack of qualifying education and social participation in sporting and leisure activities. Adapted assistance in education and participation in social life are thus important. During the coronavirus disease 2019 (COVID-19) pandemic, the pediatric population was less severely impacted by the disease, but by the restrictions associated. The aim of this study was to evaluate the impact of the COVID-19 pandemic regarding access to education and social participation for young patients with DMD in Switzerland. We conducted a survey study from May to August 2021 assessing the impact of the COVID-19 pandemic on access to education and social participation in 8 to 18 years old patients with DMD in Switzerland. Of 60 sent surveys, 40 were returned and included. Mean age of participants was 13.5 years (±3.1 standard deviation); 23/40 of the participants were wheelchair bound, 21/40 attended a special school, and 19/40 a regular school. Of the 22/40 participants receiving assistance at school, 7/40 reported a change caused by the pandemic: for 5/7, the assistance was paused. Of the 12 boys and adolescents attending sporting activities, 10 had to suspend these. Nine attended other leisure activities; for 3/9, these activities were paused. The COVID-19 pandemic had direct effects on school assistance, sporting, and leisure activities in young patients with DMD in Switzerland. It is important to ensure that school assistance and leisure activities are rapidly resumed.
Exact relationships between the GW approximation and equation-of-motion coupled-cluster theories through the quasi-boson formalism
Authors: Tölle Johannes , Kin-Lic Chan Garnet
Published: March 2023

We describe the relationship between the GW approximation and various equation-of-motion (EOM) coupled-cluster (CC) theories. We demonstrate the exact equivalence of the G0W0 approximation and the propagator theory for an electron–boson problem in a particular excitation basis. From there, we establish equivalence within the quasi-boson picture to the IP+EA-EOM unitary CC propagator. We analyze the incomplete description of screening provided by the standard similarity-transformed IP+EA-EOM-CC and the recently introduced G0W0 Tamm–Dancoff approximation. We further consider the approximate decoupling of IP and EA sectors in EOM-CC treatments and devise the analogous particle–hole decoupling approach for the G0W0 approximation. Finally, we numerically demonstrate the exact relationships and magnitude of the approximations in the calculations of a set of molecular ionization potentials and electron affinities.
Hydrodynamic interactions in ion transport—Theory and simulation
Authors: Diddens Diddo , Heuer Andreas
Published: March 2023

We present a hydrodynamic theory describing pair diffusion in systems with periodic boundary conditions, thereby generalizing earlier work on self-diffusion [B. Dünweg and K. Kremer, J. Chem. Phys. 99, 6983–6997 (1993) and I.-C. Yeh and G. Hummer, J. Phys. Chem. B 108, 15873–15879 (2004)]. Its predictions are compared with Molecular Dynamics simulations for a liquid carbonate electrolyte and two ionic liquids, for which we characterize the correlated motion between distinct ions. Overall, we observe good agreement between theory and simulation data, highlighting that hydrodynamic interactions universally dictate ion correlations. However, when summing over all ion pairs in the system to obtain the cross-contributions to the total cationic or anionic conductivity, the hydrodynamic interactions between ions with like and unlike charges largely cancel. Consequently, significant conductivity contributions only arise from deviations from a hydrodynamic flow field of an ideal fluid, which is from the local electrolyte structure as well as the relaxation processes in the subdiffusive regime. In the case of ionic liquids, the momentum-conservation constraint additionally is vital, which we study by employing different ionic masses in the simulations. Our formalism will likely also be helpful to estimate finite-size effects of the conductivity or of Maxwell-Stefan diffusivities in simulations.
Comparative enteric-methane emissions of dairy farms in northern Victoria, Australia
Authors: Munidasa Sineka , Cullen Brendan , Eckard Richard , Talukder Saranika , Barnes Lachlan , Cheng Long
Published: March 2023

Context Enteric methane (CH4) is a source of greenhouse gas (GHG) in agriculture, which needs to be reduced. A variety of feeding systems for dairy production is being used in south-eastern Australia, but there are few studies that compare CH4 emissions and emission intensity (EI) of milk production across these systems. Aims The objective was to estimate the lactating cows’ enteric-CH4 emissions, EI and their seasonal changes, across different feeding systems in northern Victoria, Australia. Methods A Tier 2 inventory methodology was used to estimate the enteric-CH4 emissions and EI. Four case-study farms were selected to represent a range of feeding systems, Farms A, B, C and D were categorised as System 4–5 (hybrid–total mixed ration system), System 4 (hybrid system), System 2 (moderate–high bail system) and System 2 respectively. Monthly feed, animal and production data were sourced from June 2019 to May 2020. Key results Average enteric-CH4 emissions of Farms A and B (13.1 and 12.9 kg CO2e/head.day respectively) were greater than those of Farms C and D (11.7 and 11.6 kg CO2e/head.day respectively). Furthermore, CH4 EI was greater in Farms C and D (0.49 and 0.48 CO2-e kg/kg fat- and protein-corrected milk (FPCM) respectively) and it was lower in both Farms A and B (0.46 CO2-e kg/kg FPCM). Overall, Farms A and B using Feeding-system 4–5 with greater-producing cows produced more CH4 but with less CH4 EI than did the Farms C and D, which are mainly pasture-based. Conclusions These findings suggest that to reduce CH4 EI requires a move towards Feeding-system 4–5. However, on the basis of the results of the current study, pasture-based systems have an advantage over hybrid/total mixed ration feeding systems, as these farms have lower absolute CH4 emissions, which helps address climate change. Implications Estimation of CH4 emissions, EI and seasonal changes in them gives farmers the opportunity to identify the mitigation strategies and plan specific strategies that fit the particular feeding system and season. However, more research needs to be conducted to check the feasibility of doing this.
Wide and deep neural networks achieve consistency for classification
Authors: Radhakrishnan Adityanarayanan , Belkin Mikhail , Uhler Caroline
Published: March 2023

While neural networks are used for classification tasks across domains, a long-standing open problem in machine learning is determining whether neural networks trained using standard procedures are consistent for classification, i.e., whether such models minimize the probability of misclassification for arbitrary data distributions. In this work, we identify and construct an explicit set of neural network classifiers that are consistent. Since effective neural networks in practice are typically both wide and deep, we analyze infinitely wide networks that are also infinitely deep. In particular, using the recent connection between infinitely wide neural networks and neural tangent kernels, we provide explicit activation functions that can be used to construct networks that achieve consistency. Interestingly, these activation functions are simple and easy to implement, yet differ from commonly used activations such as ReLU or sigmoid. More generally, we create a taxonomy of infinitely wide and deep networks and show that these models implement one of three well-known classifiers depending on the activation function used: 1) 1-nearest neighbor (model predictions are given by the label of the nearest training example); 2) majority vote (model predictions are given by the label of the class with the greatest representation in the training set); or 3) singular kernel classifiers (a set of classifiers containing those that achieve consistency). Our results highlight the benefit of using deep networks for classification tasks, in contrast to regression tasks, where excessive depth is harmful.
Oceanographic connectivity explains the intra-specific diversity of mangrove forests at global scales
Authors: Gouvêa Lidiane P. , Fragkopoulou Eliza , Cavanaugh Kyle , Serrão Ester A. , Araújo Miguel B. , Costello Mark John , Westergerling E. H. Taraneh , Assis Jorge
Published: March 2023

The distribution of mangrove intra-specific biodiversity can be structured by historical demographic processes that enhance or limit effective population sizes. Oceanographic connectivity (OC) may further structure intra-specific biodiversity by preserving or diluting the genetic signatures of historical changes. Despite its relevance for biogeography and evolution, the role of oceanographic connectivity in structuring the distribution of mangrove’s genetic diversity has not been addressed at global scale. Here we ask whether connectivity mediated by ocean currents explains the intra-specific diversity of mangroves. A comprehensive dataset of population genetic differentiation was compiled from the literature. Multigenerational connectivity and population centrality indices were estimated with biophysical modeling coupled with network analyses. The variability explained in genetic differentiation was tested with competitive regression models built upon classical isolation-by-distance (IBD) models considering geographic distance. We show that oceanographic connectivity can explain the genetic differentiation of mangrove populations regardless of the species, region, and genetic marker (significant regression models in 95% of cases, with an average R-square of 0.44 ± 0.23 and Person’s correlation of 0.65 ± 0.17), systematically improving IBD models. Centrality indices, providing information on important stepping-stone sites between biogeographic regions, were also important in explaining differentiation (R-square improvement of 0.06 ± 0.07, up to 0.42). We further show that ocean currents produce skewed dispersal kernels for mangroves, highlighting the role of rare long-distance dispersal events responsible for historical settlements. Overall, we demonstrate the role of oceanographic connectivity in structuring mangrove intra-specific diversity. Our findings are critical for mangroves’ biogeography and evolution, but also for management strategies considering climate change and genetic biodiversity conservation.
Neuronal activity-induced, equilibrative nucleoside transporter-dependent, somatodendritic adenosine release revealed by a GRAB sensor
Authors: Wu Zhaofa , Cui Yuting , Wang Huan , Wu Hao , Wan Yi , Li Bohan , Wang Lei , Pan Sunlei , Peng Wanling , Dong Ao , Yuan Zhengwei , Jing Miao , Xu Min , Luo Minmin , Li Yulong
Published: March 2023

The purinergic signaling molecule adenosine (Ado) modulates many physiological and pathological functions in the brain. However, the exact source of extracellular Ado remains controversial. Here, utilizing a newly optimized genetically encoded GPCR-Activation-Based Ado fluorescent sensor (GRAB
Ado
), we discovered that the neuronal activity–induced extracellular Ado elevation is due to direct Ado release from somatodendritic compartments of neurons, rather than from the axonal terminals, in the hippocampus. Pharmacological and genetic manipulations reveal that the Ado release depends on equilibrative nucleoside transporters but not the conventional vesicular release mechanisms. Compared with the fast-vesicular glutamate release, the Ado release is slow (~40 s) and requires calcium influx through L-type calcium channels. Thus, this study reveals an activity-dependent second-to-minute local Ado release from the somatodendritic compartments of neurons, potentially serving modulatory functions as a retrograde signal.
Regulating the reduction reaction pathways via manipulating the solvation shell and donor number of the solvent in Li-CO
2
chemistry
Authors: Zhang Wenchao , Zhang Fangli , Liu Sailin , Pang Wei Kong , Lin Zhang , Guo Zaiping , Chai Liyuan
Published: March 2023

Transforming CO
2
into valuable chemicals is an inevitable trend in our current society. Among the viable end-uses of CO
2
, fixing CO
2
as carbon or carbonates via Li-CO
2
chemistry could be an efficient approach, and promising achievements have been obtained in catalyst design in the past. Even so, the critical role of anions/solvents in the formation of a robust solid electrolyte interphase (SEI) layer on cathodes and the solvation structure have never been investigated. Herein, lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) in two common solvents with various donor numbers (DN) have been introduced as ideal examples. The results indicate that the cells in dimethyl sulfoxide (DMSO)-based electrolytes with high DN possess a low proportion of solvent-separated ion pairs and contact ion pairs in electrolyte configuration, which are responsible for fast ion diffusion, high ionic conductivity, and small polarization. The 3 M DMSO cell delivered the lowest polarization of 1.3 V compared to all the tetraethylene glycol dimethyl ether (TEGDME)-based cells (about 1.7 V). In addition, the coordination of the O in the TFSI
−
anion to the central solvated Li
+
ion was located at around 2 Å in the concentrated DMSO-based electrolytes, indicating that TFSI
−
anions could access the primary solvation sheath to form an LiF-rich SEI layer. This deeper understanding of the electrolyte solvent property for SEI formation and buried interface side reactions provides beneficial clues for future Li-CO
2
battery development and electrolyte design.
A DNA damage–induced phosphorylation circuit enhances Mec1
ATR
Ddc2
ATRIP
recruitment to Replication Protein A
Authors: Yates Luke A. , Tannous Elias A. , Morgan R. Marc , Burgers Peter M. , Zhang Xiaodong
Published: March 2023

The cell cycle checkpoint kinase Mec1
ATR
and its integral partner Ddc2
ATRIP
are vital for the DNA damage and replication stress response. Mec1–Ddc2 “senses” single-stranded DNA (ssDNA) by being recruited to the ssDNA binding Replication Protein A (RPA) via Ddc2. In this study, we show that a DNA damage–induced phosphorylation circuit modulates checkpoint recruitment and function. We demonstrate that Ddc2–RPA interactions modulate the association between RPA and ssDNA and that Rfa1-phosphorylation aids in the further recruitment of Mec1–Ddc2. We also uncover an underappreciated role for Ddc2 phosphorylation that enhances its recruitment to RPA-ssDNA that is important for the DNA damage checkpoint in yeast. The crystal structure of a phosphorylated Ddc2 peptide in complex with its RPA interaction domain provides molecular details of how checkpoint recruitment is enhanced, which involves Zn
2+
. Using electron microscopy and structural modeling approaches, we propose that Mec1–Ddc2 complexes can form higher order assemblies with RPA when Ddc2 is phosphorylated. Together, our results provide insight into Mec1 recruitment and suggest that formation of supramolecular complexes of RPA and Mec1–Ddc2, modulated by phosphorylation, would allow for rapid clustering of damage foci to promote checkpoint signaling.
Retrotransposon-mediated evolutionary rewiring of a pathogen response orchestrates a resistance phenotype in an insect host
Authors: Guo Zhaojiang , Guo Le , Bai Yang , Kang Shi , Sun Dan , Qin Jianying , Ye Fan , Wang Shaoli , Wu Qingjun , Xie Wen , Yang Xin , Crickmore Neil , Zhou Xuguo , Zhang Youjun
Published: March 2023

Ongoing host–pathogen interactions can trigger a coevolutionary arms race, while genetic diversity within the host can facilitate its adaptation to pathogens. Here, we used the diamondback moth (
Plutella xylostella
) and its pathogen

Bacillus thuringiensis

(Bt) as a model for exploring an adaptive evolutionary mechanism. We found that insect host adaptation to the primary Bt virulence factors was tightly associated with a short interspersed nuclear element (SINE - named SE2) insertion into the promoter of the transcriptionally activated
MAP4
K4
gene. This retrotransposon insertion coopts and potentiates the effect of the transcription factor forkhead box O (FOXO) in inducing a hormone-modulated Mitogen-activated protein kinase (MAPK) signaling cascade, leading to an enhancement of a host defense mechanism against the pathogen. This work demonstrates that reconstructing a
cis
–
trans
interaction can escalate a host response mechanism into a more stringent resistance phenotype to resist pathogen infection, providing a new insight into the coevolutionary mechanism of host organisms and their microbial pathogens.
New Englishes and Conversation Analysis
Authors: Neumaier Theresa
Published: March 2023

This study assesses the potential of using conversation analytic methodology to investigate syntactic variation in New Englishes. It analyses transcripts and audio files of face-to-face interactions between speakers of Caribbean and Southeast Asian Englishes and illustrates how syntax provides essential clues allowing interactants to project upcoming places of speaker change. Current speakers might adapt their turns underway to avoid transition to a next speaker, but speaker groups differ when it comes to which syntactic constructions they prefer in this context. As these interactional preferences seem to correlate with linguistic preferences (such as a high frequency of topicalization), the present study suggests that they constitute a case of emergent grammar, and hence should be considered a factor in investigating syntactic variation.
Femtosecond Fiber Laser Based on BiSbTeSe2 Quaternary Material Saturable Absorber
Authors: Xiao Yue-Jia , Xing Xiao-Wei , Cui Wen-Wen , Chen Yue-Qian , Zhou Qin , Liu Wen-Jun
Published: March 2023

Topological insulator materials, including Bi2Te3, Sb2Te3, Sb2Te3, and Bi2Se3, have attracted some attention due to their narrow band gaps, high carrier mobility, wide spectral absorption ranges and other characteristics. We report a new multi-compound topological insulator material BiSbTeSe2 that, compared with the traditional topological insulator composed of two elements, can integrate the physical advantages of each element, helpful to build an experimental platform with rich physical properties. The nonlinear optical characteristics of the quaternary material BiSbTeSe2 is obtained in the erbium-doped fiber laser. Using the BiSbTeSe2 as a saturable absorber material, the passive Q-switched and mode-locked fiber lasers are achieved. The pulse duration and signal-to-noise ratio (SNR) of the Q-switched fiber laser are 854 ns and 70 dB, respectively. Meanwhile, the pulse duration and SNR of the mode-locked fiber laser are 259 fs and 87.75 dB, respectively. This work proves that the BiSbTeSe2 has a considerable application prospect as a saturable absorber in fiber lasers, and provides a new reference for selection of high-performance saturable absorber materials.
Quantum process tomography of the single-shot entangling gate with superconducting qubits
Authors: Sakhouf Hamid , Daoud Mohammed , Ahl Laamara Rachid
Published: March 2023

A single-shot entangling gate plays a crucial role in quantum information processing due to its high fidelity. This operation gate is fast to create a maximally entangled state and forms a universal gate set for quantum computing. Currently, the preparation and demonstration of multi-qubit entanglement are achieved based on sequences of single- and two-qubit operations, yielding lower fidelity and requiring longer execution time. Here, we demonstrate by numerically simulating the use of quantum process tomography to fully characterize the performance of a single-shot three-qubit entangling gate. This gate is used to create a Greenberger–Horne–Zeilinger entangled state in Sakhouf et al (2021 J. Phys. B: At. Mol. Opt. Phys.
54 175501), directly generated by three transmon-type superconducting qubits which are mediated by a resonator with the assistance of a microwave field. Comparing ideal and simulated quantum process tomography, we characterize the entangling gate performance by calculating the mean fidelity achieving a high value

≻

0.93

.
Local dielectric function of hBN-encapsulated WS2 flakes grown by chemical vapor deposition
Authors: Ferrera Marzia , Sharma Apoorva , Milekhin Ilya , Pan Yang , Convertino Domenica , Pace Simona , Orlandini Giorgio , Peci Ermes , Ramò Lorenzo , Magnozzi Michele , Coletti Camilla , Salvan Georgeta , Zahn Dietrich R T , Canepa Maurizio , Bisio Francesco
Published: March 2023

Hexagonal boron nitride (hBN), sometimes referred to as white graphene, receives growing interest in the scientific community, especially when combined into van der Waals (vdW) homo- and heterostacks, in which novel and interesting phenomena may arise. hBN is also commonly used in combination with two-dimensional (2D) semiconducting transition metal dichalcogenides (TMDCs). The realization of hBN-encapsulated TMDC homo- and heterostacks can indeed offer opportunities to investigate and compare TMDC excitonic properties in various stacking configurations. In this work, we investigate the optical response at the micrometric scale of mono- and homo-bilayer WS2 grown by chemical vapor deposition and encapsulated between two single layers of hBN. Imaging spectroscopic ellipsometry is exploited to extract the local dielectric functions across one single WS2 flake and detect the evolution of excitonic spectral features from monolayer to bilayer regions. Exciton energies undergo a redshift by passing from hBN-encapsulated single layer to homo-bilayer WS2, as also confirmed by photoluminescence spectra. Our results can provide a reference for the study of the dielectric properties of more complex systems where hBN is combined with other 2D vdW materials into heterostructures and are stimulating towards the investigation of the optical response of other technologically-relevant heterostacks.
Time evolution of electron distributions to bimodal steady states for electrons dilutely dispersed in theinert gases Ar, Kr, and Xe with deep Ramsauer Townsend minima in themomentum transfer cross section
Authors: Huang Yin , Shizgal Bernard
Published: March 2023

The current paper considers the thermalization of an ensemble of electrons under the influence of an external electric field and dilutely dispersed in one of the inert gas moderators, Argon, Krypton or Xenon for which the electron momentum transfer cross sections have deep Ramsauer-Townsend minima. As a consequence, the steady state electron distribution functions are bimodal over a small range of external electric field strengths. The current work is directed towards the time evolution of the electron distribution function determined from the numerical solution of the Fokker-Planck equation. The kinetic theory of electrons dilutely dispersed in a heat bath of atoms at temperature T

b
has a very long history. The solution of the Fokker-Planck equation can be expressed as a sum of exponentials of the form

e

−

λ

n

t

where λ

n
are the eigenvalues of the Fokker-Planck operator. Alternatively, a finite difference algorithm is used to solve the time dependent Fokker-Planck equation to give the time dependent electron energy distribution function. We demonstrate the evolution of the initial Maxwellian into a nonequilibrium bimodal distribution which cannot be rationalized with either the Gibbs-Boltzmann entropy or the Tsallis nonextensive entropy. Instead, the time dependent approach of an initial Maxwellian to the bimodal distribution is described in terms of the Kullback-Leibler entropy. We also demonstrate the inapplicability of the Boltzmann entropy nor the Tsallis entropy for a model system with a power law momentum transfer cross section of the form, σ(x) = σ
0/x

p
, where

x
=

m

e

v

2

/

2

k

B

T

b

is the reduced speed. This model with p = 2 is also employed to demonstrate a steady-state Kappa distribution which features prominently in space physics and other fields. For p > 2, we show distribution functions that increase without bound analogous to runaway electrons. The steady nonequilibrium distributions are interpreted as solutions of a Pearson ordinary differential equation.
Existence of hidden attractors in nonlinear hydro-turbine governing systems and its stability analysis
Authors: Zhao 赵 Peng-Chong 鹏翀 , Wei 卫 Hao-Juan 皓娟 , Xu 徐 Zhen-Kun 振坤 , Chen 陈 Di-Yi 帝伊 , Xu 许 Bei-Bei 贝贝 , Wang 王 Yu-Meng 雨萌
Published: March 2023

This work studies the stability and hidden dynamics of the nonlinear hydro-turbine governing system with an output limiting link, and propose a new six-dimensional system, which exhibits some hidden attractors. The parameter switching algorithm is used to numerically study the dynamic behaviors of the system. Moreover, it is investigated that for some parameters the system with a stable equilibrium point can generate strange hidden attractors. A self-excited attractor with the change of its parameters is also recognized. In addition, numerical simulations are carried out to analyze the dynamic behaviors of the proposed system by using the Lyapunov exponent spectra, Lyapunov dimensions, bifurcation diagrams, phase space orbits, and basins of attraction. Consequently, the findings in this work show that the basins of hidden attractors are tiny for which the standard computational procedure for localization is unavailable. These simulation results are conducive to better understanding of hidden chaotic attractors in higher-dimensional dynamical systems, and are also of great significance in revealing chaotic oscillations such as uncontrolled speed adjustment in the operation of hydropower station due to small changes of initial values.
W-boson mass anomaly from a general SU(2)
L
scalar multiplet*
Authors: Wu Jiajun , Huang Da , Geng Chao-Qiang
Published: March 2023

We explain the W-boson mass anomaly by introducing an

scalar multiplet with general isospin and hypercharge {in the case without its vacuum expectation value}. It is shown that the dominant contribution from the scalar multiplet to the W-boson mass arises at the one-loop level, which can be expressed in terms of the electroweak (EW) oblique parameters T and S at leading order. We first rederive the general formulae of T and S induced by a scalar multiplet of EW charges, confirming the results in literature. We then study several specific examples of great phenomenological interest by applying these general expressions. As a result, it is found that the model with a scalar multiplet in an

real representation with

cannot generate the required

correction because it leads to vanishing values of T and S. However, the cases with scalars in a complex representation under

with a general hypercharge can explain the

excess observed by CDF-II owing to nonzero T and S. We further consider the strong constraints from the perturbativity and EW global fit of the precision data and vary the isospin representation and hypercharge of the additional scalar multiplet to assess the extent of the model to solve the W-boson mass anomaly. It turns out that these constraints play important roles in setting limits on the model parameter space. We also briefly describe the collider signatures of the extra scalar multiplet, especially when it contains long-lived, heavy, highly charged states.
Speckle-interferometric Study of Close Visual Binary System HIP 11253 (HD 14874) using Gaia (DR2 and EDR3)
Authors: Aljboor Hussam , Taani Ali
Published: March 2023

We present a comprehensive set of physical and geometrical parameters for each of the components of the close visual binary system HIP 11253 (HD 14874). We present an analysis for the binary and multiple stellar systems with the aim to obtain a match between the overall observational spectral energy distribution of the system and the spectral synthesis created from model atmospheres using Al-Wardat's method for analyzing binary and multiple stellar systems. The epoch positions are used to determine the orbital parameters and the total mass. The parameters of both components are derived as:

T

eff

a

=
6025

,

T

eff

b

=
4710

, logga = 4.55, loggb = 4.60, R
a = 1.125 R
⊙, R
b = 0.88 R
⊙, L
a = 1.849 L
⊙, L
b = 0.342 L
⊙. Our analysis shows that the spectral types of the components are F9 and K3. By combining the orbital solution with the parallax measurements of Gaia DR2 and EDR3, we estimate the individual masses using the H-R diagram as M
a = 1.09 M
⊙ and M
b = 0.59 M
⊙ for using Gaia DR2 parallax and M
a = 1.10 M
⊙ and M
b = 0.61 M
⊙ for using Gaia EDR3 parallax. Finally, the location of both system's components on the stellar evolutionary tracks is presented.
Leggett–Garg inequality in Markovian quantum dynamics: role of temporal sequencing of coupling to bath
Authors: Ghosh Sayan , Varma Anant V , Das Sourin
Published: March 2023

We study Leggett–Garg inequalities (LGIs) for a two level system (TLS) undergoing Markovian dynamics described by unital maps. We first find the analytic expression of LG parameter K
3 (simplest variant of LGIs) in terms of the parameters of two distinct unital maps representing time evolution for intervals: t
1 to t
2 and t
2 to t
3. We then show that the maximum violation of LGI for all possible unital maps can never exceed well known Lüders bound of

K

3

L

u
¨

d
e
r
s

=
3

/

2

over the full parameter space. We further show that if the map for the time interval t
1 to t
2 is non-unitary unital then irrespective of the choice of the map for interval t
2 to t
3 we can never reach Lüders bound. On the other hand, if the measurement operator eigenstates remain pure upon evolution from t
1 to t
2, then depending on the degree of decoherence induced by the unital map for the interval t
2 to t
3 we may or may not obtain Lüders bound. Specifically, we find that if the unital map for interval t
2 to t
3 leads to the shrinking of the Bloch vector beyond half of its unit length, then achieving the bound

K

3

L

u
¨

d
e
r
s

is not possible. Hence our findings not only establish a threshold for decoherence which will allow for

K

3

=

K

3

L

u
¨

d
e
r
s

, but also demonstrate the importance of temporal sequencing of the exposure of a TLS to Markovian baths in obtaining Lüders bound.
Corrugated versus smooth uniqueness and stability of negatively curved isometric immersions
Authors: Christoforou Cleopatra
Published: March 2023

We prove uniqueness of smooth isometric immersions within the class of negatively curved corrugated two-dimensional immersions embedded into

R

3

\mathbb {R}^3

. The main tool we use is the relative entropy method employed in the setting of differential geometry for the Gauss-Codazzi system. The result allows us to compare also two solutions to the Gauss-Codazzi system that correspond to a smooth and a

C

1
,
1

C^{1,1}

isometric immersion of not necessarily the same metric and prove continuous dependence of their second fundamental forms in terms of the metric and initial data in

L
2

L^2

.
Eight-year longitudinal falls trajectories and associations with modifiable risk factors: evidence from The Irish Longitudinal Study on Ageing (TILDA)
Authors: Hartley Peter , Forsyth Faye , O’Halloran Aisling , Kenny Rose Anne , Romero-Ortuno Roman
Published: March 2023

Background

The label ‘faller’ and the associated stigma may reduce healthcare-seeking behaviours. However, falls are not inevitably progressive and many drivers are modifiable. This observational study described the 8-year longitudinal trajectories of self-reported falls in The Irish Longitudinal Study on Ageing (TILDA) and studied associations with factors, including mobility, cognition, orthostatic hypotension (OH), fear of falling (FOF) and use of antihypertensive and antidepressant medications.

Methods

Participants aged ≥50 years at each wave were categorised by whether they averaged ≥2 falls in the previous year (recurrent fallers) or not (≤1 fall). Next-wave transition probabilities were estimated with multi-state models.

Results

8,157 (54.2% female) participants were included, of whom 586 reported ≥2 falls at Wave 1. Those reporting ≥2 falls in the past year had a 63% probability of moving to the more favourable state of ≤1 fall. Those reporting ≤1 fall had a 2% probability of transitioning to ≥2 falls. Besides older age and higher number of chronic conditions, factors that increased the risk of transitioning from ≤1 fall to ≥2 falls were lower Montreal Cognitive Assessment score, FOF and taking antidepressants. Conversely, male sex, higher timed up and go time, the presence of OH and being on antidepressants reduced the probability of improving from ≥2 falls to ≤1 fall.

Conclusion

The majority of recurrent fallers experienced favourable transitions. Improvements in cognitive and psychological status, psychotropic prescribing, mobility and OH may help improve trajectories. Findings may help combat stigma associated with falling and promote preventative healthcare-seeking behaviours.
Mass migration, population genetics and historical population expansion in the Neotropical butterflyKricogonia lyside(Lepidoptera: Pieridae)
Authors: Pfeiler Edward
Published: March 2023

Little is known of the migratory ecology and population genetics of the lyside sulphur butterfly Kricogonia lyside (Godart) (Pieridae: Coliadinae). Mass migrations involving huge numbers of these butterflies have long been known to occur in the southern USA, Mexico and Greater Antilles, but these reports have been based mainly on chance encounters. A review of the limited literature on migrations of K. lyside in North America is presented here, together with results from field observations of a recent mass migration in north-western Mexico. Overall, these data confirm that migrations of K. lyside are often unidirectional, but can change direction over relatively short time periods, and are most probably ‘triggered’ by substantial rainfall following a prolonged dry period. Several important questions on these enigmatic migrations, however, including, but not limited to, location of source populations, ultimate destinations, numbers of individuals involved and purpose, remain to be answered. Analysis of mitochondrial DNA barcodes revealed that genetic diversity of the cytochrome c oxidase subunit I (COI) gene is much higher in K. lyside than that seen in the long-distance migrating nymphalid butterflies, the monarch (Danaus plexippus) and painted lady (Vanessa cardui), and that a large historical population expansion occurred during the mid-Pleistocene.
B-cell lymphoma extra-large (Bcl-xL) is a promising drug target in Merkel cell carcinoma
Authors: Fan Kaiji , Srinivas Nalini , Kubat Linda , Gravemeyer Jan , Sucker Antje , Schadendorf Dirk , Gambichler Thilo , Becker Jürgen C
Published: March 2023

Background

Merkel cell carcinoma (MCC) is an aggressive skin tumor with neuroendocrine differentiation. Immunotherapies are very effective in the treatment of advanced stage MCC patients, but for patients whose tumor cannot be controlled by the immune system, alternative approaches are urgently needed.

Objective

To identify overexpressed oncogenes as potential drug targets for MCC.

Methods

NanoString platform, digital droplet PCR (ddPCR) and FISH assays were used to determine copy number variations (CNVs); BCL2L1 and PARP1 mRNA expression levels were determined by qRT-PCR, Bcl-xl and PARP1 protein by immunoblot. Specific Bcl-xL inhibitors and PARP1 inhibitor was used alone or in combination to test their antitumor effect.

Results

Screening for CNVs in 13 classic virus-positive and -negative MCC cell lines revealed BCL2L1 gains and amplifications, which were confirmed by ddPCR in 10 cell lines. By ddPCR and FISH we demonstrated that BCL2L1 gains are already present in tumor tissues. BCL2L1 copy number gains were associated with increased Bcl-xL mRNA and protein expression. However, high Bcl-xL expression was not restricted to MCC cells harboring a BCL2L1 gain/amplification, suggesting additional epigenetic means regulation. The functional relevance of Bcl-xL in MCC cells was demonstrated by the fact that specific Bcl-xL inhibitors (A1331852 and WEHI-539) led to the induction of apoptosis. Due to the strong expression and activation of PARP1 in MCC cell lines, we next tested the combination of Bcl-xL inhibitors with the PARP1 inhibitor olaparib, which indeed showed synergistic anti-tumour effects.

Conclusions

Bcl-xL, which is highly expressed in MCC, appears to be an attractive therapeutic target for the treatment of this tumor; especially since the effect of specific Bcl-xL inhibitors is synergistically enhanced by simultaneous PARP inhibition.
Comment on ‘Onset of epidermolysis bullosa acquisita under therapy with ustekinumab for the treatment of Crohn disease’
Authors: Martora Fabrizio , Battista Teresa , Potestio Luca , Scalvenzi Massimiliano , Nappa Paola , Megna Matteo
Published: March 2023

This is a comment on ‘Onset of epidermolysis bullosa acquisita under therapy with ustekinumab for the treatment of Crohn disease’.
Athena: Speciality Certificate Examination case for general dermatology and dermatology in primary health care
Authors: Punchihewa Nisal , Tandon Smriti , Poon Flora , Pawlowski Rhonda , Chan Yuen , Mar Adrian
Published: March 2023

This Athena case describes possible differential diagnoses in a 76-year-old woman who presented with an 8-month history of multiple painful ulcers on her lower abdominal wall and right anterior thigh.