bluuebunny/crossref_metadata_2025 huggingface dataset:
SPACE: Spatially variable gene clustering adjusting for cell type effect for improved spatial domain detection
Authors: Das Adhikari Sikta , Steele Nina G. , Theisen Brian , Wang Jianrong , Cui Yuehua
Published: August 2024

Recent advances in spatial transcriptomics have significantly deepened our understanding of biology. A primary focus has been identifying spatially variable genes (SVGs) which are crucial for downstream tasks like spatial domain detection. Traditional methods often use all or a set number of top SVGs for this purpose. However, in diverse datasets with many SVGs, this approach may not ensure accurate results. Instead, grouping SVGs by expression patterns and using all SVG groups in downstream analysis can improve accuracy. Furthermore, classifying SVGs in this manner is akin to identifying cell type marker genes, offering valuable biological insights. The challenge lies in accurately categorizing SVGs into relevant clusters, aggravated by the absence of prior knowledge regarding the number and spectrum of spatial gene patterns. Addressing this challenge, we propose SPACE, SPatially variable gene clustering Adjusting for Cell type Effect, a framework that classifies SVGs based on their spatial patterns by adjusting for confounding effects caused by shared cell types, to improve spatial domain detection. This method does not require prior knowledge of gene cluster numbers, spatial patterns, or cell type information. Our comprehensive simulations and real data analyses demonstrate that SPACE is an efficient and promising tool for spatial transcriptomics analysis.

Key Points

SPACE eliminates the need for prior knowledge about the number of gene clusters, known cell types, or the quantity of SVGs to identify clusters for downstream analysis.

SPACE offers a method to effectively leverage SVGs for low-dimensional embedding within each cluster to improve the accuracy of spatial domain detection.

The efficiency and utility of the SPACE algorithm have been validated across multiple datasets and simulations, demonstrating its effectiveness in producing meaningful and interpretable results.
Natural History, Phenotype Spectrum and Clinical Outcomes of Desmin (DES)-Associated Cardiomyopathy
Authors: Asatryan Babken , Rieder Marina , Murray Brittney , Muller Steven A. , Tichnell Crystal , Gasperetti Alessio , Carrick Richard T. , Joseph Emily , Leung Doris G. , te Riele Anneline S.J.M. , Zimmerman Stefan L. , Calkins Hugh , James Cynthia A. , Barth Andreas S.
Published: August 2024

Background

Pathogenic/likely pathogenic (P/LP) desmin (DES) variants cause heterogeneous cardiomyopathy and/or skeletal myopathy phenotypes. Limited data suggest a high incidence of major adverse cardiac events (MACE), including cardiac conduction disease (CCD), sustained ventricular arrhythmias (VA), and heart failure (HF) events (HF hospitalization, LVAD/cardiac transplant, HF-related death), in patients with P/LPDESvariants. However, pleiotropic presentation and small cohort sizes have limited clinical phenotype and outcome characterization.

Objectives

We aimed to describe the natural history, phenotype spectrum, familial penetrance and outcomes in patients with P/LPDESvariants through a systematic review and individual patient data meta-analysis using published reports.

Methods

We searched Medline (PubMed) and Embase for studies that evaluated cardiac phenotypes in patients with P/LPDESvariants. Cardiomyopathy diagnosis or occurrence of MACE were considered evidence of cardiac involvement/penetrance. Lifetime event-free survival from CCD, sustained VA, HF events, and composite MACE was assessed.

Results

Out of 4,212 screened publications, 71 met the inclusion criteria. A total of 230 patients were included (52.6% male, 52.2% probands, median age: 31 years [22.0; 42.8] at first evaluation, median follow-up: 3 years [0; 11.0]). Overall, 124 (53.9%) patients were diagnosed with cardiomyopathy, predominantly dilated cardiomyopathy (14.8%), followed by restrictive cardiomyopathy (13.5%), whereas other forms were less common: arrhythmogenic cardiomyopathy (7.0%), hypertrophic cardiomyopathy (6.1%), arrhythmogenic right ventricular cardiomyopathy (5.2%), and other forms (7.4%). Overall, 132 (57.4%) patients developed MACE, with 96 [41.7%] having CCD, 36 [15.7%] sustained VA, and 43 [18.7%] HF events. Familial penetrance of cardiac disease was 63.6% among relatives with P/LPDESvariants. Male sex was associated with increased risk of sustained VA (HR 2.28, p=0.02) and HF events (HR 2.45, p=0.008).

Conclusions

DEScardiomyopathy exhibits heterogeneous phenotypes and distinct natural history, characterized by high familial penetrance and substantial MACE burden. Male patients face higher risk of sustained VA events.
Predicting Walking Capacity Outcomes After Moderate to High Intensity Locomotor Training in Chronic Stroke
Authors: Garrity Christina , Reisman Darcy S , Billinger Sandra A , Butera Katie A , Boyne Pierce
Published: August 2024

Purpose: Moderate-to-high intensity locomotor training (M-HIT) is strongly recommended in stroke rehabilitation but outcomes are variable. This study aimed to identify baseline clinical characteristics that predict change in walking capacity following M-HIT in chronic stroke. Methods: This analysis used data from the HIT-Stroke Trial (N=55), which involved up to 36 sessions of either moderate or high intensity locomotor training. A prespecified model assessed how well baseline motor impairment (Fugl-Meyer lower limb motor scale [FM-LL]), comfortable gait speed (CGS), and balance confidence (Activities Balance Confidence scale [ABC]), independently explain changes in 6-minute walk distance (Δ6MWD), while controlling for treatment group. Exploratory analysis tested additional baseline covariates using the all-possible regressions procedure. The prognostic value of each potential covariate was assessed by its average contribution to the explained variance in Δ6MWD (Δ pseudo-R2). Results: With the prespecified model, 8-week Δ6MWD was significantly associated with baseline FM-LL (β=5.0 [95% CI: 1.4, 8.6]) and ABC (β=0.7 [0.0, 1.4]), but not CGS (β=-44.6 [-104.7, 15.6]). The exploratory analysis revealed the top 7 covariates with the highest mean Δ pseudo-R2were: FM-LL, pain-limited walking duration, ABC, the use of an assistive device, fatigue, depression, and recent walking exercise history >2 days per week. Conclusions: On average, participants with less motor impairment and higher balance confidence have greater walking capacity improvements after M-HIT in chronic stroke. Additional negative prognostic factors may include pain-limited walking duration, use of an assistive device, fatigue, depression, and recent walking exercise but these exploratory findings need to be confirmed in future studies.
New insights into the structure of cellulose in plant cell walls
Authors: Cresswell Rosalie , Deralia Parveen Kumar , Yoshimi Yoshihisa , Brown Steven P. , Dupree Ray , Dupree Paul
Published: August 2024

The structure of native plant cellulose, despite its abundance and utility in industry, remains elusive. The cellulose structure of several species was studied using 2D solid-state Nuclear Magnetic Resonance (NMR) of13C labelled plants. Six major glucose environments were resolved which are common to the cellulose of poplar wood, spruce wood and grasses. The cellulose structure was maintained in isolated holo-cellulose nanofibrils, allowing more detailed characterisation. There are just two glucose environments within the fibril core which have the same NMR13C chemical shifts as tunicate cellulose Iβ. The third major glucose site with a carbon 4 shift near 89 ppm, previously assigned to the fibril interior, is one of four surface glucose environments. These advances allowed us to obtain a more accurate measure of the interior to surface ratio for poplar wood fibrils of 0.5, consistent with an 18 chain microfibril structure having 6 core and 12 surface chains.
msiFlow: Automated Workflows for Reproducible and Scalable Multimodal Mass Spectrometry Imaging and Immunofluorescence Microscopy Data Processing and Analysis
Authors: Spangenberg Philippa , Bessler Sebastian , Widera Lars , Bottek Jenny , Richter Mathis , Thiebes Stephanie , Siemes Devon , Krauß Sascha D. , Migas Lukasz G. , Kasarla Siva Swapna , Phapale Prasad , Kleesiek Jens , Führer Dagmar , Moeller Lars C. , Heuer Heike , Van de Plas Raf , Gunzer Matthias , Soehnlein Oliver , Soltwisch Jens , Shevchuk Olga , Dreisewerd Klaus , Engel Daniel R.
Published: August 2024

Multimodal imaging by matrix-assisted laser desorption ionisation mass spectrometry imaging (MALDI MSI) and immunofluorescence microscopy holds great potential for understanding pathological mechanisms by mapping molecular signatures from the tissue microenvironment to specific cell populations. However, existing open-source software solutions for analysis of MALDI MSI data are incomplete, require programming skills and contain laborious manual steps, hindering broadly applicable, reproducible, and high-throughput analysis to generate impactful biological discoveries across interdisciplinary research fields. Here we present msiFlow, an accessible open-source, platform-independent and vendor-neutral software for end-to-end, high-throughput, transparent and reproducible analysis of multimodal imaging data. msiFlow integrates all necessary steps from import and pre-processing of raw MALDI MSI data to visual analysis output, as well as registration, along with state-of-the-art and newly developed algorithms, into automated workflows. Using msiFlow, we unravel the molecular heterogeneity of leukocytes in infected tissues by spatial regulation of ether-linked phospholipids containing arachidonic acid. We anticipate that msiFlow will facilitate the broad applicability of MSI in the emerging field of multimodal imaging to uncover context-dependent cellular regulations in disease states.
Sodium Chloride Promotes the Growth of Bacterial Soil Isolate and Antimicrobial Activity of Polymixin B
Authors: Singh Diwakar Kumar
Published: August 2024

The decomposition of organic matter in the soil, soil salinity, and soil acidity are influenced by soil microbiology, which also controls the recycling and processing of nutrients in the soil. These factors affect soil fertility and ecological stability. This manuscript is focused on the isolation of seven gram-negative bacteria found in the agricultural soil of The Neotia University campus, West Bengal, India. These isolates have been found to be mesophilic based on their study of their growth profiles, which revealed that under the same incubation conditions, the isolates displayed rising development patterns between 24 and 120 hours. The presence of sodium and potassium chloride modulates the growth and development of bacterial strains (DNI1, DNI2, DNI3, DNI4, DNI5, DNI6, and DNI7) during laboratory set up. The sodium and potassium chloride composition of culture media that effectively regulates the development of bacterial isolates has been determined using the combinational method of salt treatment. The ideal physical factor required for the growth and development of microorganisms has been demonstrated by the pH and temperature titration during this study. The powerful antibiotics known as polymyxin B, which are nonribosomal lipopeptides produced byPaenibacillus polymyxa, are especially effective against Gram-negative bacteria. Because multidrug-resistant Gram-negative bacteria have few other choices for treating infections, the use of polymyxins in clinical settings has increased despite their toxicity in the past. This study offers an update on the most current findings about the bioactivity of soil isolates and their significant relationships to temperature, pH, salt, and polymixin B sensitivity. The toxicity impact may be reduced by enhancing polymixin B’s antibacterial activity with salt treatment in clinical research.
A LINK BETWEEN AGING AND PERSISTENCE
Authors: Proenca A. M. , Rang C. U. , Chao L.
Published: August 2024

ABSRACT

Despite the various strategies that microorganisms have evolved to resist antibiotic treatments, most chronic infections are caused by subpopulations of susceptible bacteria in a transient state of dormancy. This phenotype, known as bacterial persistence, arises due to a natural and ubiquitous heterogeneity of growth states in bacterial populations. Nonetheless, the unifying mechanism of persistence remains unknown, with several pathways being able to trigger the phenotype. Here, we show that asymmetric damage partitioning, a form of cellular aging, produces the underlying phenotypic heterogeneity upon which persistence is triggered. Using single-cell microscopy and microfluidic devices, we demonstrate that deterministic asymmetry in exponential phase populations leads to a state of growth stability, which prevents the spontaneous formation of persisters. However, as populations approach stationary phase, aging bacteria — those inheriting more damage upon division — exhibit a sharper growth rate decline, increased probability of growth arrest, and higher persistence rates. These results indicate that persistence triggers are biased by bacterial asymmetry, thus acting upon the deterministic heterogeneity produced by cellular aging. This work suggests unifying mechanisms for persistence and offers new perspectives on the treatment of recalcitrant infections.

IMPORTANCE

Whenever bacterial cultures are treated with antibiotics, a fraction of the population survives despite exhibiting no active resistance mechanisms. These “persisters” are cells in a state of slow growth or dormancy, already present in the population prior to antibiotic exposure. Although various stressors or mutations increase persistence rates, a unifying persistence mechanism has not been established. Here, we show that cellular aging can represent such a mechanism. Bacteria age through the inheritance of intracellular damage, which occurs even in unstressed populations. As populations approach stationary phase, agingEscherichia colihave a steeper decline in elongation rates and earlier division arrest compared to younger cells. Upon antibiotic treatment, aging bacteria have higher persistence rates. These results show that stationary phase, a well-established persistence trigger, operates on the phenotypic heterogeneity produced by cellular aging. Because aging is a deterministic and ubiquitous process, it could represent a fundamental mechanism for the formation of persisters.
A Unified Atlas of T cell Glycophysiology
Authors: Izzati Fauzia N. , Choksi Hani , Giuliana Paolo , Abd-Rabbo Diala , Elsaesser Heidi , Blundell Aled , Affe Vanessa , Kannen Vinicius , Jame-Chenarboo Zeinab , Schmidt Edward , Kuypers Meggie , Avila David B. , Chiu Eric S. Y. , Badmaev Dzhangar , Cui Haissi , Matthews Jason , Mallevaey Thierry , Macauley Matthew S. , Brooks David G. , Edgar Landon J.
Published: August 2024

Glycans are emerging as important regulators of T cell function but remain poorly characterized across the functionally distinct populations that existin vivo. Here, we couple single-cell analysis technologies with soluble lectins and chemical probes to interrogate glycosylation patterns on major T cell populations across multiple mouse and human tissues. Our analysis focused on terminal glycan epitopes with immunomodulatory functions, including sialoglycan ligands for Siglecs. We demonstrate that glycosylation patterns are diverse across the resting murine T cell repertoire and dynamically remodelled in response to antigen-specific stimulation. Surprisingly, we find that human T cell populations do not share the same glycoprofiles or glycan remodelling dynamics as their murine counterparts. We show that these differences can be explained by divergent regulation of glycan biosynthesis pathways between the species. These results highlight fundamental glycophysiological differences between mouse and human T cells and reveal features that are critical to consider for glycan-targeted therapies.
Effects of lambda-cyhalothrin on gut microbiota and related bile acid metabolism in mice
Authors: Zheng Weijia , Xu Lingyuan , Jin Maojun , Wang Jing , Rietjens Ivonne M.C.M.
Published: August 2024

Background

Since the gut microbiota plays a crucial role in host metabolism and homeostasis, its alterations induced by xenobiotics, such as pesticides, could pose a risk to host health. Our previous in vitro fermentation study showed that pyrethroid pesticides could affect the mouse bacterial community and related bile acid profiles. Hence in the present study, the effects of the selected pyrethroid lambda-cyhalothrin on the intestinal microbial community and its related bile acid metabolism were evaluated in male and female mice.

Results

The total amount of bile acids in plasma and fecal samples from lambda-cyhalothrin treated mice markedly increased compared to controls, which could be mainly ascribed to the significantly raised proportions of taurine conjugated bile acids in plasma, and the increase in fecal secondary bile acids. In gut microbial profiles, a significantly increased richness ofPrevotellaceaand a depletion ofLachnospiraceaewere found at the family level upon the treatment with lambda-cyhalothrin.

Conclusion

Treatment of mice with lambda-cyhalothrin affected the gut microbiota with accompanying changes in bile acid homeostasis. The effects on fecal bile acid profiles were in line with those previously observed in our in vitro study and corroborate that pyrethroid pesticides could affect gut microbiota and related bile acid profiles.
A foggy minefield: Experiences of regulation among developers of AI and other medical software in the UK, survey and focus group study
Authors: Potts Henry WW , Bondaronek Paulina , Neves Ana Luísa , Bolotov Alex , Burgess Lucie , Shehu Jona , Spinelli Gabriella , Volpi Emanuela , El-Osta Austen
Published: August 2024

Introduction

Regulation is important for medical software, but advances in software, notably developments in artificial intelligence (AI), are developing quickly. There are concerns that regulatory processes are not keeping up and that there is a need for more pro-innovation approaches.

Methods

We conducted a survey (n = 34) and four focus groups to discuss experiences of regulation among UK-based developers.

Results

In the survey, 35% agreed/strongly agreed that they were confident in their knowledge of relevant regulation, while 50% agreed/strongly agreed that poor regulation was allowing bad products to come to market. The focus groups identified 10 themes around challenges with current processes: the process of obtaining regulatory approval is uncertain; lack of knowledge about regulatory approval; difficulties in obtaining reliable advice; complexity and slow pace of approvals; difficult to get NHS clinician involvement; process is costly and difficult to fund; implications for competition; international differences; incentives to develop lower classification products; and lack of harmonisation between NHS and MHRA. Respondents’ suggestions for solutions to improve processes fell under four themes: financial and structural support; regulatory collaboration and commissioner involvement; process efficiency and adaptability; and education and guidance.

Discussion

Developers are unhappy with the process of regulation for medical software in the UK, finding it confusing and expensive. They feel systems compare poorly to international comparators. Integration between the MHRA system and NHS commissioning is considered poor.
Does hospital overload increase the risk of death when infected by SARS-CoV-2?
Authors: Glemain Benjamin , Assaad Charles , Ghosn Walid , Moulaire Paul , de Lamballerie Xavier , Zins Marie , Severi Gianluca , Touvier Mathilde , Deleuze Jean-François ,   SAPRIS-SERO study group, Lapidus Nathanaël , Carrat Fabrice
Published: August 2024

Several studies found an association between the risk of death for COVID-19 patients and hospital overload during the first pandemic wave. We studied this association across the French departments using 82,467 serological samples and a hierarchical Bayesian model. In high-incidence areas, we hypothesized that hospital overload would increase infection fatality rate (IFR) without increasing infection hospitalization rate (IHR). We found that increasing departmental incidence from 3% to 9% rose IFR from 0.42% to 1.14%, and IHR from 1.66% to 3.61%. An increase in incidence from 6% to 12% in people under 60 was associated with an increase in the proportion of people over 60 among those infected, from 11.6% to 17.4%. Higher incidence did increase the risk of death for infected persons, probably due to an older infected population in high-incidence areas rather than hospital overload.
Extraction and Quantification of Phenolic Compounds in Maize
Authors: Gomez Lina , Jiang Nan , Grotewold Erich
Published: August 2024

Plants accumulate hundreds of thousands of specialized metabolites that participate in their interactions with the environment. Among these compounds, phenolics represent a large class, and they play important physiological roles, such as providing a first barrier against pathogens, cues to pollinators, and radiation protection. Maize is one of the most important crops worldwide for food, animal feed, and biofuels, and it has the potential to accumulate different phenolics in vegetative tissues as well as in seeds. Recent studies have identified a large number of phenolic compounds—with a diversity of chemical decorations—in different maize tissues, but these likely represent just a fraction of the metabolic diversity of maize. In this protocol, we describe a specific method for the extraction and quantification of maize phenolic compounds by ultra-high-pressure liquid chromatography–tandem multiple reaction monitoring mass spectrometry (UHPLC-MRM-MS/MS) analysis. We provide detailed instructions for the extraction of phenolics using acidic methanol, and for the quantification of 33 different compounds in maize stems, including flavonoids, phenolic acids, and lignin precursors.
Extraction and Quantification of Total Anthocyanins, Determination of Anthocyanidin Core Structures, and Characterization of Specific Anthocyanins from Maize
Authors: Jiang Nan , Gomez Lina , Grotewold Erich
Published: August 2024

Anthocyanins are flavonoid pigments that accumulate in fruits and flowers that serve as attractants for pollinators and seed-dispersing organisms. Anthocyanins exhibit diverse chemical structures, characterized both by different anthocyanidin core structures and numerous chemical modifications of the anthocyanidin core. Here, we describe a protocol for the extraction and quantification of total anthocyanins, as well as for the characterization of anthocyanidin core structures and specific anthocyanins, using a spectrophotometer, high-performance liquid chromatography (HPLC), and ultra-high-performance liquid chromatography–two-dimensional mass spectrometry (UHPLC-MS/MS). The method involves anthocyanin extraction using acidic methanol, anthocyanin quantification using a spectrophotometer, determination of anthocyanidin core structure from hydrolyzed anthocyanin extracts using UHPLC-MS/MS, separation of different anthocyanins using HPLC, and characterization of specific anthocyanins using UHPLC-MS/MS. As an example, we describe how we have used this protocol to extract and quantify total anthocyanins from maize leaves, identify cyanidin as the core anthocyanidin structure, and characterize three specific anthocyanins that accumulate in maize leaves, each having a cyanidin core with decorations of a hexose group, and a malonyl or coumaroyl moiety.
Thermodynamic properties of a relativistic Bose gas under rigid rotation
Authors: Siri E. , Sadooghi N.
Published: August 2024

We study the thermodynamic properties of a rigidly rotating relativistic Bose gas. First, we derive the solution of the equation of motion corresponding to a rotating complex Klein-Gordon field and determine the free propagator of this model utilizing the Fock-Schwinger proper-time method. Using this propagator, we then obtain the thermodynamic potential of this model in the zeroth and first perturbative level. In addition, we compute the nonperturbative ring contribution to this potential. Our focus is on the dependence of these expressions on the angular velocity, which effectively acts as a chemical potential. Using this thermodynamic potential, we calculate several quantities, including the pressure, angular momentum and entropy densities, heat capacity, speed of sound, and moment of inertia of this rigidly rotating Bose gas as functions of temperature (T), angular velocity (Ω), and the coupling constant (α). We show that certain thermodynamic instabilities appear at high temperatures and large couplings. They are manifested as zero and negative values of the above quantities, particularly the moment of inertia and heat capacity. Zero moment of inertia leads to the phenomenon of supervorticity at certain T or α. Supervortical temperatures (couplings) decrease with increasing coupling (temperature). We also observe superluminal sound velocities at high T and for large α.

Published by the American Physical Society
2024
Physics-informed machine-learning solution to log-layer mismatch in wall-modeled large-eddy simulation
Authors: Maejima Soju , Tanino Kazuki , Kawai Soshi
Published: August 2024

This study proposes a physics-informed machine learning to enable using the erroneous flow data at near-wall grid points as the input to the wall model in a wall-modeled large-eddy simulation (LES). The proposed neural network predicts the amount of numerical error in the near-wall grid-point data and inputs the physically correct flow variables into the wall model by correcting the near-wall error. The input and output features of the neural networks are selected based on the physical relations of the turbulent boundary layer for robustness against various Reynolds and Mach number conditions. The proposed neural networks allow the wall model to accurately predict the wall shear stress from the erroneous near-wall information and yields accurate predictions of the turbulence statistics. Additionally, the proposed physics-informed machine-learning approach reproduces the asymmetry in the probability density functions of the predicted wall shear stress observed in direct numerical simulations, while the conventional wall model with input away from the wall does not. The results suggest that using the near-wall information for wall modeling may increase the fidelity of the wall-modeled LES.

Published by the American Physical Society
2024
Programmable Photonic Quantum Circuits with Ultrafast Time-Bin Encoding
Authors: Bouchard Frédéric , Fenwick Kate , Bonsma-Fisher Kent , England Duncan , Bustard Philip J. , Heshami Khabat , Sussman Benjamin
Published: August 2024

We propose a quantum information processing platform that utilizes the ultrafast time-bin encoding of photons. This approach offers a pathway to scalability by leveraging the inherent phase stability of collinear temporal interferometric networks at the femtosecond-to-picosecond timescale. The proposed architecture encodes information in ultrafast temporal bins processed using optically induced nonlinearities and birefringent materials while keeping photons in a single spatial mode. We demonstrate the potential for scalable photonic quantum information processing through two independent experiments that showcase the platform’s programmability and scalability, respectively. The scheme’s programmability is demonstrated in the first experiment, where we successfully program 362 different unitary transformations in up to eight dimensions in a temporal circuit. In the second experiment, we show the scalability of ultrafast time-bin encoding by building a passive optical network, with increasing circuit depth, of up to 36 optical modes. In each experiment, fidelities exceed 97%, while the interferometric phase remains passively stable for several days.

Published by the American Physical Society
2024
Investigating the superconducting state of
2H−NbS2
as seen by the vortex lattice
Authors: Alshemi A. , Campillo E. , Forgan E. M. , Cubitt R. , Abdel-Hafiez M. , Blackburn E.
Published: August 2024

2H−NbS2 is a classic example of an anisotropic multiband superconductor, with significant recent work focusing on the interesting responses seen when high magnetic fields are applied precisely parallel to the hexagonal niobium planes. It is often contrasted with its sister compound 2H−NbSe2 because they have similar onset temperatures for superconductivity, but 2H−NbS2 has no charge density wave whereas in 2H−NbSe2 the charge density wave order couples strongly to the superconductivity. Using small-angle neutron scattering, a bulk-sensitive probe, we have studied the vortex lattice and how it responds to the underlying superconducting anisotropy. This is done by controlling the orientation of the field with respect to the Nb planes. The superconducting anisotropy, Γac=7.07±0.2, is found to be field independent over the range measured (0.15 to 1.25 T), and the magnetic field distribution as a function of the applied magnetic field is found to be in excellent quantitative agreement with anisotropic London theory modified with a core-size cutoff correction, providing the first complete validation of this model. We find values of λab=141.9±1.5 nm for the in-plane London penetration depth, and λc∼1µm for the out-of-plane response. The field-independence indicates that we are primarily sampling the larger of the two gaps generating the superconductivity in this material.

Published by the American Physical Society
2024
Phases and dynamics of few fermionic impurities immersed in two-dimensional boson droplets
Authors: Pelayo Jose Carlos , Fogarty Thomás , Busch Thomas , Mistakidis Simeon I.
Published: August 2024

We unravel the ground state properties and emergent nonequilibrium dynamics of a mixture consisting of a few spin-polarized fermions embedded in a two-dimensional bosonic quantum droplet. For an increasingly attractive droplet-fermion interaction we find a transition from a spatially delocalized fermion configuration to a state where the fermions are highly localized and isolated. This process is accompanied by the rise of induced fermion-fermion interactions mediated by the droplet. Additionally, for increasing attractive droplet-fermion coupling, undulations in the droplet density occur in the vicinity of the fermions manifesting the back-action of the latter. Following interaction quenches from strong to weaker attractive droplet-fermion couplings reveals the spontaneous nucleation of complex excitation patterns in the fermion density such as ring- and cross-shaped structures. These stem from the enhanced interference of the fermions that remain trapped within the droplet, which emulates, to a good degree, an effective potential for the fermions. The non-negligible back-action of the droplet manifests itself in the fact that the effective potential predictions are less accurate at the level of the many-body wave function. Our results provide a paradigm for physics beyond the reduced single-component droplet model, unveiling the role of back-action in droplets and the effect of induced mediated interactions.

Published by the American Physical Society
2024
Noise-Aware Variational Eigensolvers: A Dissipative Route for Lattice Gauge Theories
Authors: Cobos Jesús , Locher David F. , Bermudez Alejandro , Müller Markus , Rico Enrique
Published: August 2024

We propose a novel variational ansatz for the ground-state preparation of the Z2 lattice gauge theory (LGT) in quantum simulators. It combines dissipative and unitary operations in a completely deterministic scheme with a circuit depth that does not scale with the size of the considered lattice. We find that, with very few variational parameters, the ansatz can achieve >99% precision in energy in both the confined and deconfined phase of the Z2 LGT. We benchmark our proposal against the unitary Hamiltonian variational ansatz showing a reduction in the required number of variational layers to achieve a target precision. After performing a finite-size scaling analysis, we show that our dissipative variational ansatz can predict accurate critical exponents without requiring a number of layers that scales with the system size, which is the standard situation for unitary ansätze. Furthermore, we investigate the performance of this variational eigensolver subject to circuit-level noise, determining variational error thresholds that fix the error rate below which it would be beneficial to increase the number of layers. In light of these quantities and for typical gate errors p in current quantum processors, we provide a detailed assessment of the prospects of our scheme to explore the

Z

2

LGT on near-term devices.

Published by the American Physical Society
2024
The impact of individual, scientific and organizational factors on the adoption of AR in university education
Authors: Ronaghi Marzieh , Ronaghi Mohammad Hossein , Boskabadi Elahe
Published: August 2024

Purpose

Augmented reality (AR) is an advanced version of the dynamic physical space that is perceived and received via visual, audio, digital and other sensory stimuli. The capabilities of virtual technologies change the field of university and education considerably. The necessity of using virtual technologies in the education field was revealed more in unforeseen disasters such as the COVID-19 pandemic. The adoption of a technology by its users is an important factor in the successful implementation of the technology. The present study evaluates several factors affecting the adoption of AR technology in the realm of tertiary education.

Design/methodology/approach

This study is applied in nature, and the necessary data were gathered through a survey questionnaire. The opinions of 621 students were investigated using a simple random sampling method. The multinomial logit test was used in this research.

Findings

It was found that individual and social factors such as age, education level, major and economic characteristics such as one’s income in a month, expenses of a person in a month, the level of access to high-speed internet and access to a laptop or smartphone are effective in AR technology adoption in the field of academic education.

Originality/value

The theoretical contribution of this study is to identify the key factors that influence the adoption of AR technology and develop a model specifically applicable to the educational field. The results of this research can be used by university managers and educational policymakers for the efficient and effective use of this technology.
Effect of the countersunk rivet head dimensions on fatigue behavior of riveted specimens of 2024-T3 alloy
Authors: Lv Guocheng , Jia Dawei , Li Changyou , Zhao Chunyu , Zhang Xiulu , Yan Feng , Zhang Hongzhuang , Li Bing
Published: August 2024

Purpose

This study aims to investigate the effect of countersunk rivet head dimensions on the fatigue performance of the riveted specimens of 2024-T3 alloy.

Design/methodology/approach

The relationship between rivet head dimensions and fatigue behavior was investigated by finite element method and fatigue test. The fatigue fracture of the specimens was analyzed by scanning electron microscopy.

Findings

A change of the rivet head dimensions will cause a change in the stress concentration and residual normal stress, the stress concentration near the rivet hole causes the fatigue crack source to be located on the straight section of the countersunk rivet hole and the residual normal stress can effectively restrain the initiation and expansion of fatigue cracks. The fatigue cycle will cause the rivet holes to produce different degrees of surface wear.

Originality/value

The fatigue life of the specimens with the height of the rivet head of 2.28 mm and 2.00 mm are similar, but the specimens with the height of the rivet head of 1.72 mm were far higher than the other specimens.
Managerial ability, digital transformation and innovation efficiency: empirical evidence from Chinese manufacturing listed companies
Authors: Shan Hui , Ko Daeyoung , Wang Lan , Wang Gang
Published: August 2024

Purpose

This study aims to examine the relationship between managerial ability and innovation efficiency, the mediating effect of digital transformation and the moderating effect of internal control.

Design/methodology/approach

This study collected A-share manufacturing listed companies in China from 2008 to 2019 and analyzed the data by means of multiple regression analysis, mediating effect test, moderating effect test and heterogeneity test. Finally, the authors conducted robustness test by remeasuring key variables and adding control variables.

Findings

The empirical results show that the higher managerial ability can improve innovation efficiency, internal control has a positive moderating effect and digital transformation plays a partial mediating effect on the relationship between managerial ability and innovation efficiency. Specially, it is found that the mediating effect of digital transformation is not significant in non-state-owned firms.

Practical implications

This study suggests that it is necessary to focus on the managerial ability in terms of both cultivation and supervision, to further deepen the digital transformation from the aspects of firms, government and society, especially to support the digital transformation of non-state-owned firms, and to make efforts to improve the corporate governance mechanism and internal control system, so as to better comprehensively realize the improvement of enterprise innovation efficiency.

Originality/value

Based on the mediating effect analysis of digital transformation and the moderating effect analysis of internal control, this study explores the role of managerial ability on innovation efficiency from a new perspective, expanding the related theoretical framework and research boundaries.
On-load magnetic field calculation for linear permanent-magnet actuators using hybrid 2-D finite-element method and Maxwell–Fourier analysis
Authors: Ladghem-Chikouche Brahim , Roubache Lazhar , Boughrara Kamel , Dubas Frédéric , Djelloul-Khedda Zakarya , Ibtiouen Rachid
Published: August 2024

Purpose

The purpose of this study is to present a novel extended hybrid analytical method (HAM) that leverages a two-dimensional (2-D) coupling between the semi-analytical Maxwell–Fourier analysis and the finite element method (FEM) in Cartesian coordinates.

Design/methodology/approach

The proposed model is applied to flat permanent-magnet linear electrical machines with rotor-dual. The magnetic field solution across the entire machine is established by coupling an exact analytical model (AM), designed for regions with relative magnetic permeability equal to unity, with a FEM in ferromagnetic regions. The coupling between AM and FEM occurs bidirectionally (x, y) along the edges separating teeth regions and their adjacent regions through applied boundary conditions.

Findings

The developed HAM yields accurate results concerning the magnetic flux density distribution, cogging force and induced voltage under various operating conditions, including magnetic or geometric parameters. A comparison with hybrid finite-difference and hybrid reluctance network methods demonstrates very satisfactory agreement with 2-D FEM.

Originality/value

The original contribution of this paper lies in establishing a direct coupling between the semi-analytical Maxwell–Fourier analysis and the FEM, particularly at the interface between adjacent regions with differing magnetic parameters.
Integrating facets of information technology governance at a professional council in South Africa
Authors: Chauke Tshepo Arnold , Ngoepe Mpho
Published: August 2024

Purpose

The purpose of the study is to explore the integration of facets of information technology (IT) governance at a professional council in South Africa with the view to develop a framework.

Design/methodology/approach

This critical emancipatory study used the Information Governance Initiative pinwheel to explore the architecture facet of information governance at the professional council, with a view to developing a framework for entrenching a culture of good corporate governance. Qualitative data was collected through interviews and document analysis. The study was a participatory action research project that involved collaboration between the researcher and study participants in defining and solving the problem through a needs assessment exercise.

Findings

The key findings report on the processes taken by a professional council in identifying and implementing the facets of information governance, that is, records management, IT, content management, data governance, information security, data privacy, risk management, regulatory compliance, long-term digital preservation and, even, business intelligence.

Research limitations/implications

The study was a participatory action research project that involved collaboration between the researcher and study participants in defining and solving the problem through a needs assessment exercise.

Practical implications

The study’s findings suggest that, with the right information governance policy in place, adopting the facets of information governance can be used to address concerns related to information integrity in the short and medium terms. As a long-term option for retaining data and information, it would have various drawbacks and would not, however, ensure the initial dependability of the information.

Originality/value

A framework for information governance to ensure that the professional organisation and board members adopt a tailored governance system is suggested.
Process improvement strategy (PIS) and employee productivity amid COVID-19 pandemic among bank employees
Authors: Sulaimon Abdul-Hameed Adeola , Ametepe Paul Kojo
Published: August 2024

Purpose

This study aims to examine process improvement strategy (PIS) (proxied by remote work, workforce training, and technological innovation), and employee productivity amid the COVID-19 pandemic among bank employees.

Design/methodology/approach

The study employed cross-sectional and descriptive design by applying multistage sampling techniques using convenience sampling to select the study organization and stratified and simple random sampling to select 900 respondents for the study. Data were collected by using validated measures of the study variables designed into a questionnaire. Pearson’s correlation and simple regression analysis were employed to establish relationships and causal effects among variables respectively.

Findings

Results showed significant relationships between the PIS (work-from-home, workplace training, and technological innovation) and the outcome variable (employee productivity); and predictive capabilities between the PIS and the outcome variables (employee productivity). The study revealed that remote work accounted for the highest variability (R2 = 0.775) in employee productivity, followed by workplace training (R2 = 0.499), and finally investment in technological innovation (R2 = 0.486)] and as such PIS fosters employee productivity and may, therefore, be applied when faced with a similar pandemic in the future.

Originality/value

The study was recognized for its significance in examining how PIS supports enhancing employee productivity in banks and, by extension, other organizations during a pandemic. The research has proven to be crucial in providing insights into bank management in emerging economies and other organizations worldwide that have previously gone unnoticed during a pandemic. It has aided in the extension of existing literature on PIS and employee productivity by carefully developing a framework, thus covering practical knowledge gaps.
The effect of political environment on security and privacy of contact tracing apps evaluation
Authors: Alnsour Yazan , Juma’h Ahmad H.
Published: August 2024

Purpose

Contact tracing apps have emerged to collect data and mitigate the spread of infectious diseases. However, privacy and security concerns have caused individuals to hesitate to adopt these solutions. Our objective is to evaluate the role of the political environment, information privacy, security and users’ intentions to use contact tracing apps.

Design/methodology/approach

We scraped the digital app store and collected 399 relevant reviews and other data from 21 contact tracing apps in the USA. A semi-supervised machine learning model was developed to extract information on privacy and security aspects from the reviews.

Findings

Our findings show a positive connection between security controls and user adoption, as reflected in star ratings. Users residing in states with blue political environments tend to assign higher ratings to apps, especially when robust security controls are in place. These findings confirm the influence of the political environment on the adoption of contact tracing apps. In times of a pandemic, our findings suggest that users prioritize security over privacy concerns, emphasizing the critical role of strong security features in promoting app acceptance.

Originality/value

This paper emphasizes the political environment of the state offering the app intersects with concerns about security and privacy as well as the effectiveness of security and privacy measures, influencing the app’s ratings. Also, it shows the importance of understanding and addressing the role of the political environment when designing and promoting such public health tools, regardless of the specific disease or outbreak.
What do medical students know about sustainable development?
Authors: Borlu Arda , Coşkun Aslan Tuğba , Durmus Hasan , Öner Neslihan , Tat Ayşe Nur
Published: August 2024

Purpose

The purpose of this study is to evaluate the level of sustainability consciousness (SC) and sustainable development (SD) awareness of medical students, as well as to identify the factors associated with them.

Design/methodology/approach

This cross-sectional and descriptive study was conducted among 1,435 medical students. The socio-demographic questionnaire and the sustainability consciousness questionnaire (SCQ-L) were the data collection instruments.

Findings

A significant proportion of medical students had not heard of the concept of SD (63.6%), only 7.9% of the participants reported that they could define the SD concept. Female gender and good economic status were associated with significantly higher median SCQ-L total score (p = 0.001). Although all SD goals are closely related to health, almost half of the medical students reported no impact on SD. Besides, 47.8% of the medical students reported that physicians could have an active role in achieving SD.

Social implications

As the realization of SD and health services are closely linked, it is important to examine the sustainability knowledge, attitude and behavior of health professionals.

Originality/value

This study examined the SD awareness and SC knowledge, attitude and behavior among medical students, the leading health-care professionals of the future.