bluuebunny/crossref_metadata_2025 huggingface dataset:
Optimizing growth chamber conditions for maintaining Arcticlichen‐dominatedbiocrusts
Authors: Ficko Sarah A. , McClymont Alexandra , Haughland Diane L. , Naeth M. Anne
Published: February 2023

Optimizing growth chamber conditions for Arctic lichen biocrusts will create new opportunities to assess and prioritize reclamation techniques given the challenges associated with conducting arctic field work. Our study is the first to examine growth chamber conditions for optimizing survival and growth of Arctic lichen biocrusts, as measured by changes in lichen cover. We assessed effects of substrate crossed with substrate depth, substrate sterilization, lichen inoculation and community composition, and watering frequency in four concurrent experiments over 6 weeks on survival of arctic biocrusts collected from Diavik Diamond Mine Inc., Northwest Territories, Canada. Mixed species declined less thanFlavocetraria cucullata, and substrate affectedF. cucullatasurvival over time. Live lichen cover declined least with a 3‐day watering frequency and substrate depth of 1 cm. Sterilization did not affect lichen survival, and no contamination was observed over 6 weeks. Our results highlight the challenges of maintaining and growing lichens under controlled conditions, as only a few treatments showed increases in cover. Our research shows that even short‐term growth chamber experiments have potential to screen reclamation treatments prior to field assessments, permitting reclamation scientists to optimize limited time and resources while in the field.
Preference‐Aligned Fertility Management as a Person‐Centered Alternative to Contraceptive Use‐Focused Measures
Authors: Holt Kelsey , Galavotti Christine , Omoluabi Elizabeth , Challa Sneha , Waiswa Peter , Liu Jenny
Published: February 2023

Equating contraceptive use with programmatic success is fundamentally flawed in failing to account for whether individuals desire contraceptive use; this is problematic because nonuse can reflect empowered decision‐making and use may reflect an individual's inability to refuse or discontinue a method. A rights‐based approach demands respect for individuals’ freedom to weigh options and choose how their desire for pregnancy prevention can be accommodated by available methods and within the context of their own personal, social, and material constraints. We offer an alternative construct, preference‐aligned fertility management (PFM), that provides a more holistic indicator of whether one's contraceptive needs are met. PFM is more person‐centered and informative for programming than status quo measures of unmet need, demand satisfied, and contraceptive use which define a positive outcome in relation to pregnancy risk rather than one's stated preferences. The PFM approach goes beyond other recent proposals for modifying the concept of unmet need by refraining from judgment of legitimate reasons for nonuse of contraception and offers a straightforward way to capture whether people act in line with their preferences. We conclude with discussion of how we plan to measure PFM in the Innovations for Choice and Autonomy (ICAN) study in Nigeria and Uganda.
Near ambient pressure–x-ray photoelectron spectroscopy spectra of lithium bis(trifluoromethane-sulfonyl) imide in propylene carbonate
Authors: Dietrich Paul M. , Gerlein Lydia , Maibach Julia , Thissen Andreas
Published: February 2023

Near ambient pressure–x-ray photoelectron spectroscopy (NAP-XPS) is a less traditional form of XPS that allows samples to be analyzed at relatively high pressures, i.e., at greater than 5000 Pa. NAP-XPS can probe moderately volatile liquids, biological samples, porous materials, and/or polymeric materials that outgas significantly. In this submission, we show the survey, Li 1s, S 2p, C 1s, N 1s, O 1s, and F 1s NAP-XPS spectra of a Li-based electrolyte solution, which is a material that would be difficult to analyze by conventional XPS. The measurements were performed at 200 Pa in ambient gas atmosphere to compensate for surface charging. Peak fits of the C 1s, O 1s, and F 1s narrow scans are presented.
Body Composition Asymmetry in University Rugby Players: Influence of Sex, Position, and Injury
Authors: Cohen Tamara R. , Rosenstein Brent , Rizk Amanda , Frenette Stephane , Fortin Maryse
Published: February 2023

Context: Measures of side-to-side asymmetry in body composition may help identify players who are predisposed to lower limb injuries (LLI) or lower back pain (LBP). This study aimed to examine (1) side-to-side asymmetry in college rugby players according to sex and position and (2) whether side-to-side asymmetry is associated with LBP or LLI. Design: Cross-sectional study. Methods: Thirty-six rugby players (61% female) underwent a dual-energy X-ray absorptiometry assessment for total and regional (appendicular, truncal) outcomes of fat mass, lean mass, and bone mass. A subsample (n = 23) of players had a second dual-energy X-ray absorptiometry assessment 2 months postbaseline. Two-way analysis of variance was used to assess the effect of position (forward and backs) and sex on body composition asymmetry. Student paired t tests were used to assess side-to-side difference in body composition and compare baseline and follow-up measures. Logistic regression was used to assess possible associations between LLI, LBP, and the degree of side-to-side asymmetry in body composition. Results: Male players had greater asymmetry in arm bone mass compared with female players (P = .026), and trunk fat mass asymmetry was greater in forwards as compared with backs (P = .017). Forwards had significantly greater fat mass (P = .004) and percentage of fat (P = .048) on the right leg compared with the left. Backs had significantly greater bone mass in the right arm compared with the left (P = .015). From baseline to postseason, forwards had a significant increase in side-to-side asymmetry in arm lean mass (P = .006) and a significant decrease in side-to-side asymmetry in leg fat mass (P = .032). In backs, side-to-side asymmetry at baseline compared with postseason was significantly different (P = .011) for trunk fat mass. There were no significant associations between body composition asymmetry, LLI, or LBP by sex or position. Conclusion: Our results revealed the presence of side-to-side asymmetries in body composition in university rugby players between sex and position. The amount of asymmetry, however, was not associated with LBP and LLI.
A spatiotemporal complexity architecture of human brain activity
Authors: Krohn Stephan , von Schwanenflug Nina , Waschke Leonhard , Romanello Amy , Gell Martin , Garrett Douglas D. , Finke Carsten
Published: February 2023

The human brain operates in large-scale functional networks. These networks are an expression of temporally correlated activity across brain regions, but how global network properties relate to the neural dynamics of individual regions remains incompletely understood. Here, we show that the brain’s network architecture is tightly linked to critical episodes of neural regularity, visible as spontaneous “complexity drops” in functional magnetic resonance imaging signals. These episodes closely explain functional connectivity strength between regions, subserve the propagation of neural activity patterns, and reflect interindividual differences in age and behavior. Furthermore, complexity drops define neural activity states that dynamically shape the connectivity strength, topological configuration, and hierarchy of brain networks and comprehensively explain known structure-function relationships within the brain. These findings delineate a principled complexity architecture of neural activity—a human “complexome” that underpins the brain’s functional network organization.
Postglacial adaptations enabled colonization and quasi-clonal dispersal of ammonia-oxidizing archaea in modern European large lakes
Authors: Ngugi David Kamanda , Salcher Michaela M. , Andrei Adrian-Stefan , Ghai Rohit , Klotz Franziska , Chiriac Maria-Cecilia , Ionescu Danny , Büsing Petra , Grossart Hans-Peter , Xing Peng , Priscu John C. , Alymkulov Salmor , Pester Michael
Published: February 2023

Ammonia-oxidizing archaea (AOA) play a key role in the aquatic nitrogen cycle. Their genetic diversity is viewed as the outcome of evolutionary processes that shaped ancestral transition from terrestrial to marine habitats. However, current genome-wide insights into AOA evolution rarely consider brackish and freshwater representatives or provide their divergence timeline in lacustrine systems. An unbiased global assessment of lacustrine AOA diversity is critical for understanding their origins, dispersal mechanisms, and ecosystem roles. Here, we leveraged continental-scale metagenomics to document that AOA species diversity in freshwater systems is remarkably low compared to marine environments. We show that the uncultured freshwater AOA, “CandidatusNitrosopumilus limneticus,” is ubiquitous and genotypically static in various large European lakes where it evolved 13 million years ago. We find that extensive proteome remodeling was a key innovation for freshwater colonization of AOA. These findings reveal the genetic diversity and adaptive mechanisms of a keystone species that has survived clonally in lakes for millennia.
Zebra-inspired stretchable, biodegradable radiation modulator for all-day sustainable energy harvesters
Authors: Han Won Bae , Heo Se-Yeon , Kim Donghak , Yang Seung Min , Ko Gwan-Jin , Lee Gil Ju , Kim Dong-Je , Rajaram Kaveti , Lee Joong Hoon , Shin Jeong-Woong , Jang Tae-Min , Han Sungkeun , Kang Heeseok , Lim Jun Hyeon , Kim Do Hyeon , Kim Soo Hyun , Song Young Min , Hwang Suk-Won
Published: February 2023

Recent advances in passive radiative cooling systems describe a variety of strategies to enhance cooling efficiency, while the integration of such technology with a bioinspired design using biodegradable materials can offer a research opportunity to generate energy in a sustainable manner, favorable for the temperature/climate system of the planet. Here, we introduce stretchable and ecoresorbable radiative cooling/heating systems engineered with zebra stripe–like patterns that enable the generation of a large in-plane temperature gradient for thermoelectric generation. A comprehensive study of materials with theoretical evaluations validates the ability to accomplish the target performances even under external mechanical strains, while all systems eventually disappear under physiological conditions. Use of the zebra print for selective radiative heating demonstrates an unexpected level of temperature difference compared to use of radiative cooling emitters alone, which enables producing energy through resorbable silicon-based thermoelectric devices. The overall result suggests the potential of scalable, ecofriendly renewable energy systems.
Epigenetic modification of
CSDE1
locus dictates immune recognition of nascent tumorigenic cells
Authors: Lv Jiadi , Zhou Yabo , Zhou Nannan , Wang Zhenfeng , Chen Jie , Chen Haoran , Wang Dianheng , Zhou Li , Wei Keke , Zhang Huafeng , Tang Ke , Ma Jingwei , Liu Yuying , Wan Yonghong , Zhang Yi , Zhang Haizeng , Huang Bo
Published: February 2023

Weak immunogenicity of tumor cells is a root cause for the ultimate failure of immunosurveillance and immunotherapy. Although tumor evolution can be shaped by immunoediting toward a less immunogenic phenotype, mechanisms governing the initial immunogenicity of primordial tumor cells or original cancer stem cells remain obscure. Here, using a single tumor-repopulating cell (TRC) to form tumors in immunodeficient or immunocompetent mice, we demonstrated that immunogenic heterogeneity is an inherent trait of tumorigenic cells defined by the activation status of signal transducer and activator of transcription 1 (STAT1) protein in the absence of immune pressure. Subsequent investigation identified that the RNA binding protein cold shock domain–containing protein E1 (CSDE1) can promote STAT1 dephosphorylation by stabilizing T cell protein tyrosine phosphatase (TCPTP). A methyltransferase SET and MYN domain–containing 3 (SMYD3) was further identified to mediate H3K4 trimethylation of
CSDE1
locus, which was under the regulation of mechanotransduction by cell-matrix and cell-cell contacts. Thus, owing to the differential epigenetic modification and subsequent differential expression of CSDE1, nascent tumorigenic cells may exhibit either a high or low immunogenicity. This identified SMYD3-CSDE1 pathway represents a potential prognostic marker for cancer immunotherapy effectiveness that requires further investigation.
Supplemental Material: Sea-level fluctuations control the distribution of highly liquefaction-prone layers on volcanic-carbonate slopes
Authors: Sultan Nabil , al. et
Published: February 2023

Age model and the details of the probability of liquefaction calculations. 
Prognostic significance ofKMT2A-PTD in patients with acute myeloid leukaemia: a systematic review and meta-analysis
Authors: Ye Wu , Ma Mingzhu , Wu Xia , Deng Jili , Liu Xiaoyan , Zheng Xue , Gong Yuping
Published: February 2023

Objectives

WhetherKMT2A-PTD has a prognostic impact on patients with acute myeloid leukaemia (AML) is controversial. Therefore, we conducted a meta-analysis to assess the prognostic value ofKMT2A-PTD in patients with AML.

Methods

Eligibility criteria: we included studies concerning the prognostic value ofKMT2A-PTD in patients with AML.

Information sources: Eligible studies were identified from PubMed, Embase, Medline, Web of Science, Cochrane Library and Chinese Biomedical Database. The systematic search date was 19 December 2020.

Risk of bias: Sensitivity analysis was used to evaluate the stability and reliability of the combined results. Begg’s and Egger’s tests were used to assess the publication biases of studies.

Synthesis of results: We calculated the pooled HRs and their 95% CIs for overall survival (OS) and event-free survival (EFS) by Stata V.12 software.

Results

Included studies: 18 studies covering 6499 patients were included.

Synthesis of results:KMT2A-PTD conferred shorter OS in total population (HR=1.30, 95% CI 1.09 to 1.51). In the subgroup analysis,KMT2A-PTD also resulted in shorter OS in karyotypically normal AML patients (HR=2.72, 95% CI 1.83 to 3.61) and old AML patients (HR=1.93, 95% CI 1.44 to 2.42).KMT2A-PTD indicated no prognostic impact on EFS in total population (HR=1.26, 95% CI 0.86 to 1.66). However, in the sensitivity analysis,KMT2A-PTD resulted in poor EFS (HR=1.34, 95% CI 1.04 to 1.64) when deleting the study with a relatively obvious effect on the combined HR. In the subgroup analysis,KMT2A-PTD was associated with poor EFS in old AML patients (HR=1.64, 95% CI 1.25 to 2.03).

Conclusion

The findings indicated thatKMT2A-PTD had an adverse impact on the prognosis of patients with AML in the total population, and the conclusion can also be applied to some subgroups including karyotypically normal AML and old AML patients.KMT2A-PTD may be a promising genetic biomarker in patients with AML in the future.

Trial registration number

CRD42021227185.
Handling of missing data with multiple imputation in observational studies that address causal questions: protocol for a scoping review
Authors: Mainzer Rheanna , Moreno-Betancur Margarita , Nguyen Cattram , Simpson Julie , Carlin John , Lee Katherine
Published: February 2023

Introduction

Observational studies in health-related research often aim to answer causal questions. Missing data are common in these studies and often occur in multiple variables, such as the exposure, outcome and/or variables used to control for confounding. The standard classification of missing data as missing completely at random, missing at random (MAR) or missing not at random does not allow for a clear assessment of missingness assumptions when missingness arises in more than one variable. This presents challenges for selecting an analytic approach and determining when a sensitivity analysis under plausible alternative missing data assumptions is required. This is particularly pertinent with multiple imputation (MI), which is often justified by assuming data are MAR. The objective of this scoping review is to examine the use of MI in observational studies that address causal questions, with a focus on if and how (a) missingness assumptions are expressed and assessed, (b) missingness assumptions are used to justify the choice of a complete case analysis and/or MI for handling missing data and (c) sensitivity analyses under alternative plausible assumptions about the missingness mechanism are conducted.

Methods and analysis

We will review observational studies that aim to answer causal questions and use MI, published between January 2019 and December 2021 in five top general epidemiology journals. Studies will be identified using a full text search for the term ‘multiple imputation’ and then assessed for eligibility. Information extracted will include details about the study characteristics, missing data, missingness assumptions and MI implementation. Data will be summarised using descriptive statistics.

Ethics and dissemination

Ethics approval is not required for this review because data will be collected only from published studies. The results will be disseminated through a peer reviewed publication and conference presentations.

Trial registration number

This protocol is registered on figshare (https://doi.org/10.6084/m9.figshare.20010497.v1).
Health-related quality of life associated with sensory impairment in Chinese middle-aged and older adults: a cohort study
Authors: Ding Yue , Yan Yuhan , Tian Yong , Du Wei , Fan Lijun
Published: February 2023

Background

The impact of sensory impairment (SI) on individual multidimensional health has not been adequately explored in developing countries. This study examined the association of hearing or/and visual impairment with health-related quality of life (HRQoL) in the Chinese middle-aged and older population, and further explored potential discrepancies in associations by gender and rural–urban residence.

Methods

This cohort study used four-wave data during 2011–2018 from the China Health and Retirement Longitudinal Study, and enrolled 13 342 community-dwelling adults aged 45 years or older. We employed linear mixed effects models to estimate the longitudinal associations between SI and HRQoL, and conducted interaction tests to assess gender or rural–urban differences in above associations.

Results

Hearing impairment (HI) and visual impairment (VI) were separately and jointly associated with deteriorated overall HRQoL and decreased physical/mental component of HRQoL (all β<0, all p<0.05), and in particular, dual sensory impairment (DSI) exhibited greater impacts on HRQoL than either HI or VI alone. The impacts of SI on HRQoL were more evident among women or rural population than their counterparts (all p for interaction<0.05).

Conclusion

This study observed decreased HRQoL in association with SI. The greater impact of DSI underlines the need for integrated care for comorbid sensory conditions. Our findings also indicate the necessity to reduce the burden of SI among more vulnerable populations such as females and rural adults.
Risk factors and predictors of intracranial hemorrhage after mechanical thrombectomy in acute ischemic stroke: insights from the Stroke Thrombectomy and Aneurysm Registry (STAR)
Authors: Ironside Natasha , Chen Ching-Jen , Chalhoub Reda M , Wludyka Peter , Kellogg Ryan T , Al Kasab Sami , Ding Dale , Maier Ilko , Rai Ansaar , Jabbour Pascal , Kim Joon-tae , Wolfe Stacey Q , Starke Robert M , Psychogios Marios-Nikos , Shaban Amir , Arthur Adam S , Yoshimura Shinichi , Grossberg Jonathan A , Alawieh Ali , Fragata Isabel , Polifka Adam J , Mascitelli Justin R , Osbun Joshua W , Matouk Charles , Levitt Michael R , Dumont Travis M , Cuellar-Saenz Hugo H , Williamson Richard , Romano Daniele G , Crosa Roberto Javier , Gory Benjamin , Mokin Maxim , Moss Mark , Limaye Kaustubh , Kan Peter , Spiotta Alejandro M , Park Min S
Published: February 2023

Background

Reducing intracranial hemorrhage (ICH) can improve patient outcome in acute ischemic stroke (AIS) intervention. We sought to identify ICH risk factors after AIS thrombectomy.

Methods

This is a retrospective review of the Stroke Thrombectomy and Aneurysm Registry (STAR) database. All patients who underwent AIS thrombectomy with available ICH data were included. Multivariable regression models were developed to identify predictors of ICH after thrombectomy. Subgroup analyses were performed stratified by symptom status and European Cooperative Acute Stroke Study (ECASS) grade.

Results

The study cohort comprised 6860 patients. Any ICH and symptomatic ICH (sICH) occurred in 25% and 7% of patients, respectively. Hemorrhagic infarction 1 (HI1) occurred in 36%, HI2 in 24%, parenchymal hemorrhage 1 (PH1) in 22%, and PH2 in 17% of patients classified by ECASS grade. Intraprocedural complications independently predicted any ICH (OR 3.8083, P<0.0001), PH1 (OR 1.9053, P=0.0195), and PH2 (OR 2.7347, P=0.0004). Race also independently predicted any ICH (black: OR 0.5180, P=0.0017; Hispanic: OR 0.4615, P=0.0148), sICH (non-white: OR 0.4349, P=0.0107), PH1 (non-white: OR 3.1668, P<0.0001), and PH2 (non-white: OR 1.8689, P=0.0176), with white as the reference. Primary mechanical thrombectomy technique also independently predicted ICH. ADAPT (A Direct Aspiration First Pass Technique) was a negative predictor of sICH (OR 0.2501, P<0.0001), with stent retriever as the reference.

Conclusions

This study identified ICH risk factors after AIS thrombectomy using real-world data. There was a propensity towards a reduced sICH risk with direct aspiration. Procedural complications and ethnicity were predictors congruent between categories of any ICH, sICH, PH1, and PH2. Further investigation of technique and ethnicity effects on ICH and outcomes after AIS thrombectomy is warranted.
Characterising airway obstructive, dysanaptic and PRISm phenotypes of prematurity-associated lung disease
Authors: Cousins Michael , Hart Kylie , Kotecha Sarah J , Henderson A John , Watkins W John , Bush Andrew , Kotecha Sailesh
Published: February 2023

Introduction

Although obstructive airway disease has been shown to be associated with prematurity, other spirometry phenotypes are less well described.

Objectives

We characterised abnormal spirometry phenotypes in preterm-born children, including prematurity-associated obstructive lung disease (POLD, forced expiratory volume in 1 s (FEV1)<lower limit of normal (LLN), FEV1/forced vital capacity (FVC)<LLN), prematurity-associated preserved ratio of impaired spirometry (pPRISm, FEV1<LLN, FEV1/FVC≥LLN) and prematurity-associated dysanapsis (pDysanapsis, FEV1≥LLN, FEV1/FVC<LLN), and associated them with early life factors, bronchodilator responsiveness and fractional exhaled nitric oxide (FENO).

Methods

768 children, aged 7–12 years, underwent FENOmeasurements and spirometry before and after salbutamol. Groups were compared using parametric tests; multinomial regression was used.

Results

22.6% of 544 preterm-born (mean gestation: 31 weeks) and 9.2% of 195 term-born children, with satisfactory data available, were classified into one of four abnormal spirometry groups. Each phenotype was generally more prevalent in preterm-born children than in the term-born children. For the preterm group, POLD-reversible (4.4%) was associated with increased FENO, bronchopulmonary dysplasia (BPD) and intrauterine growth restriction. POLD-fixed group (3.3%) did not have increased FENObut was associated with BPD. 41% of the pDysanapsis group (5.9%) had bronchodilator response, 31% had increased FENOand was associated with postnatal weight gain. In the pPRISm group (9%), 13% responded to bronchodilators, FENOwas not increased and was non-significantly associated with body mass index (p=0.064).

Conclusions

Further to airway obstruction, we describe airway dysanapsis and pPRISm spirometry phenotypes in survivors of prematurity, both of which have poor outlook in other disease groups. By identifying specific phenotypes, targeted therapy can be developed to improve long-term outcomes.
Early relaparotomy following pediatric living-donor liver transplantation: experience in an Indonesian national referral hospital
Authors: Rahayatri Tri Hening , Soeratman Alif Rizqy , Muhammad Amin Rusdah Binti , Margiadi Dalia Benchamas , Tamba Riana Pauline , Kasahara Mureo
Published: February 2023

Background

Living donor liver transplantation (LDLT) remains the only curative treatment for children with end-stage liver disease; however, complications of the procedure are associated with indications for early relaparotomy. Several risk factors associated with early relaparotomy after liver transplantation include pediatric end-stage liver disease (PELD) score, warm ischemia time (WIT), and cold ischemia time (CIT). Our study investigated the incidence and indications of early relaparotomy in postoperative pediatric LDLT recipients and compared the outcomes with patients who did not require relaparotomy.

Methods

A retrospective cohort study of pediatric LDLT recipients from Cipto Mangunkusumo Hospital, Jakarta, Indonesia, was collected from 2010 to August 2022. Indications for early relaparotomy were investigated. Factors analyzed in the early relaparotomy group compared with the nonrelaparotomy group included intraoperative blood loss, surgery duration, CIT, WIT, and PELD score.

Results

The highest indication for early relaparotomy was biliary leakage. Most patients who underwent early relaparotomy only had one incidence of relaparotomy (60%). The surgery duration in subjects with early relaparotomy was longer by a median of 3 hours compared with those without early relaparotomy (p=0.289). Intraoperative blood loss was greater in early relaparotomy subjects than in subjects without early relaparotomy (95 vs 77 mL/kg, p=0.552). Other factors, such as PELD score, CIT, and WIT, also showed no significant difference between the two groups.

Conclusion

Biliary leakage was the most common indication for early relaparotomy in our center. There were no preoperative or intraoperative factors that significantly influenced the incidence of early relaparotomy due to the limited sample size and the early advancement of our liver transplant center.
Vacuum birefringence at one-loop in a supercritical magnetic field superposed with a weak electric field and application to pulsar magnetosphere
Authors: Kim Chul Min , Kim Sang Pyo
Published: February 2023

Recent ultra-intense lasers of subcritical fields and proposed X-ray polarimetry for highly magnetized neutron stars of supercritical fields have attracted attention to vacuum birefringence, a unique feature of the nonlinear vacuum under strong electromagnetic fields. We propose a formulation of the vacuum birefringence in a strong magnetic field ($${\textbf{B}}$$
B
) and a weak electric field ($${\textbf{E}}$$
E
), including the effect of electromagnetic wrench ($$G \equiv -{\textbf{E}}\cdot {\textbf{B}}\ne 0$$

G
≡
-
E
·
B
≠
0

). To do so, we derive a closed expression of the one-loop effective Lagrangian for the combined magnetic and electric fields by using the formula of the one-loop effective Lagrangian for an arbitrarily strong magnetic field. We then employ the expression to derive the polarization and magnetization of the vacuum, from which we obtain the permittivity and permeability for a weak probe field. Specifically, we find the refractive indices and the associated polarization vectors of the probe field for the case of parallel magnetic and electric fields. The proposed formulation reproduces the known results for pure magnetic fields in the proper limit. Finally, we apply the formulation to the Goldreich–Julian pulsar model. Our formulation reveals the importance of the electromagnetic wrench in vacuum birefringence: it can reduce the difference between refractive indices and rotate polarization vectors to a significant degree. Such a quantitative understanding is crucial to the X-ray polarimetry for magnetized neutron stars or magnetars, which will demonstrate the fundamental feature of the strongly-modified quantum vacuum and estimate the extreme fields surrounding those astrophysical bodies.
Scale invariant Einstein–Cartan theory in three dimensions
Authors: Adak Muzaffer , Ozdemir Nese , Sert Ozcan
Published: February 2023

We retreat the well-known Einstein–Cartan theory by slightly modifying the covariant derivative of spinor field by investigating double cover of the Lorentz group. We first write the Lagrangian consisting of the Einstein–Hilbert term, Dirac term and a scalar field term in a non-Riemannian spacetime with curvature and torsion. Then by solving the affine connection analytically we reformulate the theory in the Riemannian spacetime in a self-consistent way. Finally we discuss our results and give future perspectives on the subject.
Black holes surrounded by Einstein clusters as models of dark matter fluid
Authors: Jusufi Kimet
Published: February 2023

We construct a novel class of spherically symmetric and asymptotically flat black holes and naked singularities surrounded by anisotropic dark matter fluid with the equation of state (EoS) of the form $$P_t=\omega \rho $$

P
t

=
ω
ρ

. We assume that dark matter is made of weakly interacting particles orbiting around the supermassive black hole in the galactic center and the dark matter halo is formed by means of Einstein clusters having only tangential pressure. In the large distance from the black hole we obtain the constant flat curve with the upper bound for the dark matter state parameter $$\omega \lesssim 10^{-7}$$

ω
≲

10

-
7

. To this end, we also check the energy conditions of the dark matter fluid outside the black hole/naked singularity, the deflection of light by the galaxy, and the shadow images of the Sgr A$$^\star $$

⋆

black hole using the rotating and radiating particles. For the black hole case, we find that the effect of dark matter fluid on the shadow radius is small, in particular the angular radius of the black hole is shown to increase by the order $$10^{-4}\, \upmu $$

10

-
4

μ

arcsec compared to the vacuum solution. For the naked singularity we obtain significantly smaller shadow radius compared to the black hole case. Finally, we study the stability of the S2 star orbit around Sgr A$$^\star $$

⋆

black hole under dark matter effects. It is argued that the motion of S2 star orbit is stable for values $$\omega \lesssim 10^{-7}$$

ω
≲

10

-
7

, however further increase of $$\omega $$
ω
leads to unstable orbits. Using the observational result for the shadow images of the Sgr A$$^\star $$

⋆

reported by the EHT along with the tightest constraint for $$\omega $$
ω
found from the constant flat curve, we show that the black hole model is consistent with the data while the naked singularity in our model can be ruled out.
Molecular dynamics simulation of surface phenomena due to high electronic excitation ion irradiation in amorphous silica
Authors: Prada Alejandro , Sánchez-Pérez Francisco , Bailly-Grandvaux Mathieu , Bringa Eduardo , Caturla María José , Perlado José Manuel , Kohanoff Jorge , Peña-Rodríguez Ovidio , Rivera Antonio
Published: February 2023

We studied by means of an atomistic model based on molecular dynamics the thermal evolution of surface atoms in amorphous silica under high electronic excitation produced by irradiation with swift heavy ions. The model was validated with the total and differential yields measured in sputtering experiments with different ions and ion energies showing a very good quantitative prediction capability. Three mechanisms are behind the evolution of the surface region: (1) an ejection mechanism of atoms and clusters with kinetic energy exceeding their binding energy to the sample surface, which explains the experimentally observed angular distributions of emitted atoms, and the correlation of the total sputtering yield with the electronic stopping power and the incidence angle. (2) A collective mechanism of the atoms in the ion track originated by the initial atom motion outwards the track region subsequently followed by the return to the resulting low-density region in the track center. The collective mechanism describes the energy dissipation of bulk atoms and the changes in density, residual stress, defect formation and optical properties. (3) A flow mechanism resulting from the accumulation and subsequent evolution of surface atoms unable to escape. This mechanism is responsible for the crater rim formation.

Graphic Abstract
Significance of thermal conductivity and heat transfer mechanism through copper nanofluid with convective condition via heated Riga plate
Authors: Kumar Pardeep , Poonia Hemant , Gandhi Rishu , Sombir  , Ali Liaqat
Published: February 2023

This study investigates the heat and mass transfer of magnetohydrodynamic nanofluids via the Riga plate subjected to convective boundary conditions, including the thermal radiation parameter. Utilizing variable thermal conductivity and mixed convection effects, the heat transfer process is investigated. The peculiarity of the flow model enables us to investigate the importance of thermophoresis and Brownian motion to the kinetics of Newtonian fluids. The governing partial differential equations are converted into non-dimensional ordinary differential equations using proper similarity transformations and numerically solved using bvp4c in Matlab. The graphs explore the effects of pertinent parameters on the transference of heat, mass and velocity profiles. As the Biot number [Formula: see text] increases, so does the thermal boundary layer. The Nusselt number intensifies with radiation parameter but decreases with intensifying magnetic field parameter [Formula: see text], Eckert number [Formula: see text] and Brownian motion parameter [Formula: see text]. The influence of several physical quantities is illustrated and displayed through graphs and tables. Furthermore, it is observed that the thickness of the temperature profile is increased by combining the Biot number, the thermal radiation parameter, the thermal conductivity parameter and the modified Hartmann number.
Correlation in momentum space of Tonks–Girardeau gas
Authors: Hao Yajiang , Liu Yiwang , Yin Xiangguo
Published: February 2023

In momentum space, we investigate the correlation properties of the ground state of Tonks–Girardeau gases. With Bose–Fermi mapping method, the exact ground state wavefunction in coordinate space can be obtained based on the wavefunction of spin-polarized Fermions. By Fourier transformation we obtain the ground state wavefunction in momentum space, and therefore the pair correlation and the reduced one-body density matrix (ROBDM) in momentum space, whose diagonal part is the momentum distribution. The ROBDM in momentum space is the Fourier transformation of the ROBDM in coordinate space and the pair correlation in momentum space is the Fourier transformation of the reduced two-body density matrix in coordinate space. The correlations in momentum space display larger values only in small momentum region and vanish in most other regions. The lowest natural orbital and occupation distribution in momentum space are also obtained.
A GENERALIZED FRACTIONAL ORDER MODEL FOR COV-2 WITH VACCINATION EFFECT USING REAL DATA
Authors: JEELANI MOHAMMADI BEGUM , ALNAHDI ABEER S. , ABDO MOHAMMED S. , ALMALAHI MOHAMMED A. , ALHARTHI NADIYAH HUSSAIN , SHAH KAMAL
Published: February 2023

This work is devoted to studying the transmission dynamics of CoV-2 under the effect of vaccination. The aforesaid model is considered under fractional derivative with variable order of nonsingular kernel type known as Atangan–Baleanue–Caputo (ABC). Fundamental properties of the proposed model including equilibrium points and [Formula: see text] are obtained by using nonlinear analysis. The existence and uniqueness of solution to the considered model are investigated via fixed point theorems due to Banach and Krasnoselskii. Also, the Ulam–Hyers (UH) approach of stability is used for the said model. Further numerical analysis is investigated by using fundamental theorems of AB fractional calculus and the iterative numerical techniques due to Adams–Bashforth. Numerical simulations are performed by using different values of fractional-variable order [Formula: see text] for the model. The respective results are demonstrated by using real data from Saudi Arabia for graphical presentation.
Distributed ℋ
2
-Matrices for Boundary Element Methods
Authors: Börm Steffen
Published: February 2023

Standard discretization techniques for boundary integral equations, e.g., the Galerkin boundary element method, lead to large densely populated matrices that require fast and efficient compression techniques like the fast multipole method or hierarchical matrices. If the underlying mesh is very large, running the corresponding algorithms on a distributed computer is attractive, e.g., since distributed computers frequently are cost-effective and offer a high accumulated memory bandwidth.

Compared to the closely related particle methods, for which distributed algorithms are well-established, the Galerkin discretization poses a challenge, since the supports of the basis functions influence the block structure of the matrix and therefore the flow of data in the corresponding algorithms. This article introduces distributed ℋ
2
-matrices, a class of hierarchical matrices that is closely related to fast multipole methods and particularly well-suited for distributed computing. While earlier efforts required the global tree structure of the ℋ
2
-matrix to be stored in every node of the distributed system, the new approach needs only local multilevel information that can be obtained via a simple distributed algorithm, allowing us to scale to significantly larger systems. Experiments show that this approach can handle very large meshes with more than 130 million triangles efficiently.
Client-Specific Upgrade Compatibility Checking via Knowledge-Guided Discovery
Authors: Zhu Chenguang , Zhang Mengshi , Wu Xiuheng , Xu Xiufeng , Li Yi
Published: February 2023

Modern software systems are complex, and they heavily rely on external libraries developed by different teams and organizations. Such systems suffer from higher instability due to incompatibility issues caused by library upgrades. In this article, we address the problem by investigating the impact of a library upgrade on the behaviors of its clients. We developed
CompCheck
, an automated upgrade compatibility checking framework that generates incompatibility-revealing tests based on previous examples.
CompCheck
first establishes an offline knowledge base of incompatibility issues by mining from open source projects and their upgrades. It then discovers incompatibilities for a specific client project, by searching for similar library usages in the knowledge base and generating tests to reveal the problems. We evaluated
CompCheck
on 202 call sites of 37 open source projects and the results show that
CompCheck
successfully revealed incompatibility issues on 76 call sites, 72.7% and 94.9% more than two existing techniques, confirming
CompCheck
’s applicability and effectiveness.
Code-line-level Bugginess Identification: How Far have We Come, and How Far have We Yet to Go?
Authors: Guo Zhaoqiang , Liu Shiran , Liu Xutong , Lai Wei , Ma Mingliang , Zhang Xu , Ni Chao , Yang Yibiao , Li Yanhui , Chen Lin , Zhou Guoqiang , Zhou Yuming
Published: February 2023

Background.
Code-line-level bugginess identification (CLBI) is a vital technique that can facilitate developers to identify buggy lines without expending a large amount of human effort. Most of the existing studies tried to mine the characteristics of source codes to train supervised prediction models, which have been reported to be able to discriminate buggy code lines amongst others in a target program.

Problem.
However, several simple and clear code characteristics, such as complexity of code lines, have been disregarded in the current literature. Such characteristics can be acquired and applied easily in an unsupervised way to conduct more accurate CLBI, which also can decrease the application cost of existing CLBI approaches by a large margin.

Objective.
We aim at investigating the status quo in the field of CLBI from the perspective of (1) how far we have really come in the literature, and (2) how far we have yet to go in the industry, by analyzing the performance of state-of-the-art (SOTA) CLBI approaches and tools, respectively.

Method.
We propose a simple heuristic baseline solution GLANCE (aimin
G
at contro
L
-
AN
d
C
ompl
E
x-statements) with three implementations (i.e., GLANCE-MD, GLANCE-EA, and GLANCE-LR). GLANCE is a two-stage CLBI framework: first, use a simple model to predict the potentially defective files; second, leverage simple code characteristics to identify buggy code lines in the predicted defective files. We use GLANCE as the baseline to investigate the effectiveness of the SOTA CLBI approaches, including natural language processing (NLP) based, model interpretation techniques (MIT) based, and popular static analysis tools (SAT).

Result.
Based on 19 open-source projects with 142 different releases, the experimental results show that GLANCE framework has a prediction performance comparable or even superior to the existing SOTA CLBI approaches and tools in terms of 8 different performance indicators.

Conclusion.
The results caution us that, if the identification performance is the goal, the real progress in CLBI is not being achieved as it might have been envisaged in the literature and there is still a long way to go to really promote the effectiveness of static analysis tools in industry. In addition, we suggest using GLANCE as a baseline in future studies to demonstrate the usefulness of any newly proposed CLBI approach.
An Ethnographic Study of Multiple Factors Influencing Perceptions, Attitudes, and Observance of COVID-19 Preventive Measures among Rural and Urban Slum Dwellers in Ghana
Authors: Aberese-Ako Matilda , Immurana Mustapha , Dalaba Maxwell Ayindenaba , Anumu Fidelis E. Y. , Ofosu Anthony , Gyapong Margaret
Published: February 2023

Background. The COVID-19 pandemic and government-led interventions to tackle it have had life-changing effects on vulnerable populations, especially rural and urban slum dwellers in developing countries. This ethnographic study explored how the Ghanaian government’s management of COVID-19, socio-cultural factors, infrastructural challenges, and poverty influenced community perceptions, attitudes, and observance of COVID-19 prevention measures in Ghana. Methods. The study employed focused ethnography using in-depth interviews (IDIs), focus group discussions (FGDs), and nonparticipant observations to collect data from an urban slum and a rural community as well as from government officials, from October 2020 to January 2021. The data were triangulated and analyzed thematically with the support of qualitative software NVivo 12. All ethical procedures were followed. Results. The Ghanaian government’s strategy of communicating COVID-19-related information to the public, health-related factors such as health facilities failing to follow standard procedures in testing and tracing persons who came into contact with COVID-19-positive cases, poverty, and lack of social amenities contributed to the poor observance of COVID-19 preventive measures. In addition, the government’s relaxation of COVID-19 restrictions, community and family values, beliefs, and misconceptions contributed to the poor observance of COVID-19 preventive measures. Nevertheless, some aspects of the government’s intervention measures and support to communities with COVID-19 prevention items, support from nongovernmental organizations (NGOs), and high knowledge of COVID-19 and its devastating effects contributed to positive attitudes and observance of COVID-19 preventive measures. Conclusion. There is a need for the government to use the existing community structures to engage vulnerable communities so that their concerns are factored into interventions to ensure that appropriate interventions are designed to suit the context. Moreover, the government needs to invest in social amenities in deprived communities. Finally, the government has to be consistent with the information it shares with the public to enhance trust relations.
The Burden and In-Hospital Mortality of Stroke Admissions at a Tertiary Level Hospital in Namibia: A Retrospective Cohort Study
Authors: Neshuku Saara Ndinelago , Kirchner-Frankle Jessica , Nangolo Maria , Moses Maria , Einbeck Chalese Olivia , Kumire Percy , Zatjirua Vaja , Banda Justor
Published: February 2023

Background. Despite stroke being a leading cause of morbidity and mortality globally, there is a dearth of information on the burden and outcomes of stroke in sub-Saharan Africa and Namibia in particular. Methods. A hospital-based, retrospective cohort study was conducted to analyse non-electronic medical records of all consecutive stroke patients who were admitted to one of the highest tertiary-level hospitals in Namibia for 12 months (2019-2020). The primary outcome of the study was to establish the in-hospital mortality, stroke subtypes, and associated complications. Results. In total, 220 patients were included in the study, their mean age was 53 (SD13.8) years, and 55.5% were males. 61.0% had an ischaemic stroke (IS), and 39.0% had a haemorrhagic stroke (HS). The mean age was significantly lower in patients with HS vs. IS (

48.2
±
12.2

vs.

56.1
±
13.3

,

p
<
0.001

). Of the IS patients, the majority (29.0%) had total anterior circulation infarct (TACI), while in the HS group, 34.0% had basal ganglia haemorrhage with or without intraventricular extension. Hypertension (

p
=
0.015

), dyslipidaemia (

p
=
0.001

), alcohol consumption (

p
=
0.022

), and other cardiovascular diseases (

p
=
0.007

) were more prevalent in patients with IS compared to those with HS. The prevalence rate of intravenous thrombolysis was 2.2% in IS and use of intravenous antihypertensives in 25.9% of patients with HS than IS. The in-hospital mortality was 26.4% with complications such as raised ICP, aspiration pneumonia, hydrocephalus, and sepsis significantly high in those that died. Aspiration pneumonia (OR 2.79, 95% CI 1.63-4.76,

p
<
0.001

) and increased ICP (OR 0.30, 95% CI 0.16-057,

p
<
0.001

) were independent predictors of in-hospital mortality on the multivariate analysis. Conclusion. Our findings showed a younger mean age for stroke and mortality rate comparable to other low- to middle-income countries (LMICs). Hypertension and alcohol consumption were the main risk factors for both stroke subtypes, while aspiration pneumonia and raised intracranial pressure predicted in-hospital mortality.