bluuebunny/crossref_metadata_2025 huggingface dataset:
Prevalence and Predictors of Preterm Delivery among Mothers at the Tamale Teaching Hospital in the Tamale Metropolis of Ghana
Authors: Agyemang George Sarpong , Gmanyami Jonathan Mawutor , Appiah Elvis Angelo , Bosoka Samuel Adolf , Gohoho Mawuli , Alorwu James , Sorengmen Amos Ziema , Haruna Umar , Amoakoh Michael Yaw , Kweku Margaret
Published: June 2024

Background

Preterm delivery (PTD) remains a global public health challenge. It is estimated that 15 million babies are born prematurely. Developing countries account for 18.3% of PTD. This study assessed the prevalence and risk factors associated with PTD deliveries in the Tamale Metropolis.

Methods

A cross-sectional study accessed the birth records and interviewed 318 participants who delivered at the Tamale Teaching Hospital between January to December 2021. Univariate and multivariate regression models predicted the risk factors of PTD.

Results

The prevalence of preterm delivery was 18.5%. Women with multiple pregnancies who had a caesarean section and large household size were 4.28, 7.31 and 6.88, times more likely to have preterm delivery [AOR = 4.28 (95% CI: 1.75-24.23)], [AOR = 7.31 (95% CI: 2.59-36.14)] and [AOR = 6.88 (95% CI: 1.56-30.38)] respectively. Women who had normal haemoglobin concentration levels at 36 weeks and those who had pipe-borne water as the source of drinking water were 90% and 78% less likely to have preterm delivery [AOR = 0.10 (95% CI: 0.03-0.33)] and [AOR = 0.22 (95% CI: 0.06-0.78)] respectively.

Conclusion

There is a high prevalence of preterm delivery in the Tamale Metropolis. Having multiple pregnancies, caesarean sections and large household size are risk factors of preterm birth. Whilst maintaining a normal haemoglobin at 36 weeks and drinking pipe-borne water are protective factors against preterm delivery in the Tamale metropolis.
Prompting is all you need: LLMs for systematic review screening
Authors: Cao Christian , Sang Jason , Arora Rohit , Kloosterman Robbie , Cecere Matt , Gorla Jaswanth , Saleh Richard , Chen David , Drennan Ian , Teja Bijan , Fehlings Michael , Ronksley Paul , Leung Alexander A , Weisz Dany E , Ware Harriet , Whelan Mairead , Emerson David B , Arora Rahul , Bobrovitz Niklas
Published: June 2024

Systematic reviews (SRs) are the highest standard of evidence, shaping clinical practice guidelines, policy decisions, and research priorities. However, their labor-intensive nature, including an initial rigorous article screen by at least two investigators, delays access to reliable information synthesis. Here, we demonstrate that large language models (LLMs) with intentional prompting can match human screening performance. We introduce Framework Chain-of-Thought, a novel prompting approach that directs LLMs to systematically reason against predefined frameworks. We evaluated our prompts across ten SRs covering four common types of SR questions (i.e., prevalence, intervention benefits, diagnostic test accuracy, prognosis), achieving a mean accuracy of 93.6% (range: 83.3-99.6%) and sensitivity of 97.5% (89.7-100%) in full-text screening. Compared to experienced reviewers (mean accuracy 92.4% [76.8-97.8%], mean sensitivity 75.1% [44.1-100%]), our full-text prompt demonstrated significantly higher sensitivity in four reviews (p<0.05), significantly higher accuracy in one review (p<0.05), and comparable accuracy in two of five reviews (p>0.05). While traditional human screening for an SR of 7000 articles required 530 hours and $10,000 USD, our approach completed screening in one day for $430 USD. Our results establish that LLMs can perform SR screening with performance matching human experts, setting the foundation for end-to-end automated SRs.
Race-dependent variability in the human tumor mycobiome
Authors: Coster Dan , Margalit Thomy , Boursi Ben , Shamir Ron
Published: June 2024

Introduction

Recently, Narunsky-Haziza et. al. showed that fungi species identified in a variety of cancer types may have prognostic and diagnostic signficane. We used that data in order to better understand the effects of demographic factors (age, sex, BMI, and race) on the intratumor mycobiome composition.

Materials and Methods

We first tested the data in view of recent critiques of microbiome data processing procedures, and concluded that the batch correction and transformation used on it may produce false signals. Instead, we explored 14 combinations of data transformation and batch correction methods on data of 224 fungal species across 13 cancer types. Propensity scores were utilized to adjust for potential confounders such as histological type and tumor stage. To minimize false outcomes, we identified as positive results only those fungi species that showed significant difference in abundance across a demographic factor within a particular cancer type, using data normalized according to all 14 combinations.

Results and Discussion

We observed significant differences in fungal species abundance within tumors for certain demographic characteristics. Most differences were among races in specific cancers. The findings indicate that there are intricate interactions among the mycobiome, cancer types, and patient demographics. Our study highlights the need for accounting for potential confounders in order to further understanding of the mycobiome’s role in cancer, and underscores the importance of data processing techniques.
The safety and efficacy of using age-adjusted D-dimers in hospitalised patients in a diverse urban centre: a real-world data study
Authors: Gallier S. , Evison F. , Hodson J. , Khosla R. , Ranasinghe T. , Rickard L. , Atkin C. , Reddy-Kolanu V. , Nirantharakumar K. , Lester W. , Holloway B. , Sapey E.
Published: June 2024

Objective

Despite recommendations, age adjusted thresholds (AAT) for D Dimers are not routinely used as part of venous thromboembolism (VTE) screening in many healthcare settings due to concerns about missing cases, especially in older and co-morbid adults. The National Institute for Health and Care Excellence in the UK has highlighted that evidence to support AAT is not plentiful. This study assessed the real-world use of AAT D-dimers for VTE in a large cohort of acutely hospitalised patients.

Methods

This retrospective data study included all adult patients attending a large hospital with a suspected VTE between January 2017 to December 2021. The predictive accuracy of D-dimer was assessed against gold standard imaging. Outcomes of false negative (with AAT) and false positives (with standard thresholds) cases were assessed.

Results

27,526 suspected VTE attendances were included, with a 4.3% confirmed VTE diagnosis rate. The ST D-dimer exhibited high sensitivity (91.1%) but modest specificity (65.2%). The AAT demonstrated slightly lower sensitivity (87.0%) but higher specificity (71.7%, p<0.001). The performance of ST thresholds declined with age, with false positive rates increasing from 17.4% to 80.0% in people aged < 50 years and > 90 years respectively. The AAT accurately identified 1,700 true negatives misclassified as false positives by the ST. 14 patients in this group were admitted with a bleed within 30 days. AAT misdiagnosed 24 cases as false negatives, with most being small sub-segmental pulmonary emboli or non-occlusive DVTs. Using AAT thresholds could have avoided 64 scans per 1,000 attendances, saving approximately £235,310 of imaging costs in this cohort.

Conclusion

The age-adjusted D-dimer threshold enhances diagnostic precision and could decrease unnecessary imaging and anticoagulation, reducing investigations with time and cost savings with no significant safety signal.
Mapping the Brain Network of Conduct Disorder: Heterogeneous fMRI findings converge on a Common Brain Circuit
Authors: Dugre Jules R , Potvin Stephane
Published: June 2024

Conduct disorder (CD) is among the most prevalent and burdensome disorders in early adolescence. Over the past decade, there has been growing interest in identifying reliable and localized neurobiological markers of conduct disorder (CD). However, recent meta-analyses have highlighted the weak reliability of these so-called markers, thereby limiting the ability to draw firm conclusions. Using normative network mapping (598 healthy subjects), we rather sought to investigate whether the heterogeneous findings across studies may map unto a common brain network. A meta-analysis of 38 fMRI studies involving adolescents with a CD (932 cases, 975 controls) was first conducted and showed only a very weak spatial convergence in brain activity alterations in the anterior temporal lobe (5 out of 38 studies). In turn, network mapping revealed that findings across studies show a consistent connectivity pattern across the whole brain, with regional overlap reaching up to 94.7% (36 out of 38 studies). This network was primarily driven by functional connectivity of brainstem nuclei, subcortical structures (i.e., thalamus, ventral striatum), cingulate cortex (i.e., anterior to posterior midcingulate), superior temporal sulcus, and visual cortices. We further describe the neurochemicals and genetic markers of this CD-Network with emphasis on midbrain serotoninergic, dopaminergic and cholinergic projections. Our findings suggest that our understanding of the neurobiological markers of CD could be enhanced by viewing the brain as a complex interconnected system rather than reducing its complexity to a limited number of brain structures. More importantly, this CD-Network may serve as evidence that the various theories of CD can be reconciled rather than seen as conflicting.
Association of sexual orientation with substance use in Colombian adults experiencing homelessness
Authors: Campo-Arias Adalberto , Pineda-Roa Carlos Alejandro , Herazo Edwin
Published: June 2024

The study’s objective was to quantify the association of sexual orientation with substance use among Colombian adults experiencing homelessness. A secondary analysis of the Census of Street Inhabitants - CHC-2020 was completed. Three thousand five hundred forty-seven participants between 18 and 75 years participated, and 3.16% reported lesbian, gay, or bisexual (LGB) sexual orientation. LGB sexual orientation was associated with alcohol consumption (OR = 2.14, 95%CI 1.46 - 3.14]), cigarettes (OR = 1.70, 95%CI 1.12 - 2.56), cannabis (OR = 1.58, 95%CI 1.07 - 2.33), cocaine (OR = 2.13, 95%CI 1.30 - 3.50) and benzodiazepines (OR = 2.15, 95%CI 1.19-3.89). In conclusion, Colombian adults experiencing homelessness with gay or lesbian sexual orientation have twice the risk of consuming alcohol, cigarettes, cannabis, cocaine, and benzodiazepines than heterosexuals. More studies are needed on this population.
Dengue Virus Surveillance in Nepal Yields the First On-Site Whole Genome Sequences of Isolates from the 2022 Outbreak
Authors: Napit Rajindra , Ngono Annie Elong , Mihindukulasuriya Kathie A. , Pradhan Aunji , Khadka Binod , Shrestha Smita , Droit Lindsay , Paredes Anne , Karki Lata , Khatiwada Ravindra , Tamang Mamata , Chalise Bimal Sharma , Rawal Manisha , Jha Bimlesh , Wang David , Handley Scott A. , Shresta Sujan , Manandhar Krishna Das
Published: June 2024

Background

The 4 serotypes of dengue virus (DENV1-4) can each cause potentially deadly dengue disease, and are spreading globally from tropical and subtropical areas to more temperate ones. Nepal provides a microcosm of this global phenomenon, having met each of these grim benchmarks. To better understand DENV transmission dynamics and spread into new areas, we chose to study dengue in Nepal and, in so doing, to build the onsite infrastructure needed to manage future, larger studies.

Methods and Results

During the 2022 dengue season, we enrolled 384 patients presenting at a hospital in Kathmandu with dengue-like symptoms; 79% of the study participants had active or recent DENV infection (NS1 antigen and IgM). To identify circulating serotypes, we screened serum from 50 of the NS1+participants by RT-PCR and identified DENV1, 2, and 3 – with DENV1 and 3 codominant. We also performed whole-genome sequencing of DENV, for the first time in Nepal, using our new on-site capacity. Sequencing analysis demonstrated the DENV1 and 3 genomes clustered with sequences reported from India in 2019, and the DENV2 genome clustered with a sequence reported from China in 2018.

Conclusion

These findings highlight DENV’s geographic expansion from neighboring countries, identify China and India as the likely origin of the 2022 DENV cases in Nepal, and demonstrate the feasibility of building onsite capacity for more rapid genomic surveillance of circulating DENV. These ongoing efforts promise to protect populations in Nepal and beyond by informing the development and deployment of DENV drugs and vaccines in real time.
TGFβ determines morphology and key cellular processes of activated CD4+T cells
Authors: Eizenberg-Magar Inbal , Rimer Jacob , Miller Stav , Elyahu Yehezqel , Mark Michal , Porat Ziv , Reich-Zeliger Shlomit , Monsonego Alon , Antebi Yaron E , Friedman Nir
Published: June 2024

During an immune response, cells are simultaneously exposed to multiple cytokine signals that collectively determine their phenotype. Transforming growth factor β (TGFβ) is a pleiotropic cytokine acting as a key regulator of T-cell differentiation with activating and suppressive effects on their immune function. Here we identify and analyze the cellular responses of CD4+T cells to TGFβ across signaling contexts by analyzing the responses of T cells to multiple cytokine mixtures in the presence or absence of TGFβ. We found that TGFβ had a profound dominant effect independent of the presence of other cytokines, modulating the expression of more than 4,000 genes. In the presence of TGFβ, cells exhibit lower expression of translation-related and apoptosis-related genes, accompanied by increased survival of activated T cells. Notably, cells cultured in the presence of TGFβ were smaller in size while preserving their proliferative ability. Accordingly, we identified a dense network of transcription factors that were modulated by TGFβ, suggesting a core gene set connecting TGFβ signaling to the regulation of T-cell size. We found N-Myc to be at the center of this network, and we directly show that TGFβ regulates its gene expression level, protein level, and nuclear localization. Our work provides a system to study cell size control and demonstrate the profound effect of TGFβ in the modulation and regulation of T-cell properties, expanding its role beyond guiding their phenotype.
P-cadherin mechanoactivates tumor–mesothelium metabolic coupling to promote ovarian cancer metastasis
Authors: Ma Jing , To Sally K. Y. , Fung Katie S. W. , Wang Kun , Zhang Jiangwen , Ngan Alfonso H. W. , Yung Susan , Chan Tak-Mao , Wong Carmen C. L. , Ip Philip P. C. , Peng Ling , Guo Hong-Yan , Chan Chi Bun , Wong Alice S.T.
Published: June 2024

Peritoneal metastasis exacerbates the prognosis of ovarian cancer patients. Adhesion of cancer cells to mesothelium is a rate-limiting prerequisite for this process. How metastatic cells sense and respond to the dynamic biomechanical microenvironment at the mesothelial niche to initiate metastatic lesions remains unclear. Here, the study demonstrates that highly metastatic (HM), but not non-metastatic (NM) ovarian cancer cells, selectively activate the peritoneal mesothelium. Atomic force microscopy reveals that HM cells exert increased adhesive force on mesothelial cells via P-cadherin, a cell-cell adhesion molecule abundant in late-stage tumors. Transcriptomic and molecular analyses show that mechanical induction of P-cadherin enhances lipogenic gene expression and lipid content in HM cells by SREBP1. P-cadherin activation does not affect lipogenic activity but induces glycolysis in the interacting mesothelium. Targeted lipidomic analysis reveals that lactate produced by the glycolytic mesothelium facilitates metastatic outgrowth as a direct substrate forde novolipogenesis. Inhibiting lactate shuttling via nanodelivery of siRNA targeting P-cadherin or MCT1/4 transporters significantly suppresses metastasis in mice. The association of high fatty acid synthase in patient metastatic samples and increased P-cadherin expression supports enhancedde novolipogenesis in the metastatic niche. The study reveals P-cadherin-mediated mechano-metabolic coupling as a promising target to restrain peritoneal metastasis.
Antibiotic self-medication in Otuke district, northern Uganda: Prevalence and associated factors
Authors: Adoko Denis Diko , Nakaziba Rebecca
Published: June 2024

Antibiotic self-medication is a form of irrational drug use that contributes to antimicrobial resistance, which results in increasing health care costs and morbidity and mortality rates in the population. The misuse of antimicrobial agents is highly linked with the growing problem of antimicrobial resistance within the population globally. Unless addressed, antibiotic self-medication will drive the world back to the pre-antibiotic era, with people dying helplessly due to infectious diseases. This study aimed to investigate the prevalence of antibiotic self-medication and its associated factors in the Otuke District, Northern Uganda. A community-based cross-sectional study was conducted in the Otuke Town Council, Otuke district. The data of adults aged 18 years and above were collected using a semi-structured questionnaire, and the data were coded and entered into SPSS software version 26. The data were descriptively analyzed for frequencies and percentages. Bivariant and multivariant analyses were performed to determine associations between the variables. Out of 385 participants, 68% self-medicated with antibiotics in the past 12 months. Freedom from drug use (AOR: 3.071; 95% CI: 1.203, 7.876) and unregulated use of antibiotics (AOR at 95% CI: 8.288 (2.815, 24.397)) were more likely to lead to ASM (p value <0.001). Other significant factors included knowledge of antibiotics, previous symptom experience, previous successful treatment, long waiting hours and poor staff attitudes (p value <0.05). The most common self-medicated antibiotics were amoxicillin, Ampiclox and metronidazole.

Antibiotic self-medication in the Otuke district is very high due to the availability of medicines and lack of functional drug use regulatory frameworks. The district and government of Uganda should design and implement measures to mitigate this widespread antimicrobial misuse to prevent the development of antimicrobial resistance.
Less is more: selection from a small set of options improves BCI velocity control
Authors: Alcolea Pedro , Ma Xuan , Bodkin Kevin , Miller Lee E. , Danziger Zachary C.
Published: June 2024

We designed the discrete direction selection (DDS) decoder for intracortical brain computer interface (iBCI) cursor control and showed that it outperformed currently used decoders in a human-operated real-time iBCI simulator and in monkey iBCI use. Unlike virtually all existing decoders that map between neural activity and continuous velocity commands, DDS uses neural activity to select among a small menu of preset cursor velocities. We compared closed-loop cursor control across four visits by each of 48 naïve, able-bodied human subjects using either DDS or one of three common continuous velocity decoders: direct regression with assist (an affine map from neural activity to cursor velocity), ReFIT, and the velocity Kalman Filter. DDS outperformed all three by a substantial margin. Subsequently, a monkey using an iBCI also had substantially better performance with DDS than with the Wiener filter decoder (direct regression decoder that includes time history). Discretizing the decoded velocity with DDS effectively traded high resolution velocity commands for less tortuous and lower noise trajectories, highlighting the potential benefits of simplifying online iBCI control.
PandemicVibrio parahaemolyticuswave succession by gene loss
Authors: Yang Chao , Qiu Hongling , Svensson Sarah L. , Ni Chengpei , Gao Song , Jia Zhizhou , Wen Huiqi , Xie Li , Xu Wenxuan , Qin Yujiao , Lin Shuzhu , Wang Jiancheng , Zhang Yiquan , Li Yinghui , Jiang Min , Shi Xiaolu , Hu Qinghua , Zhou Zhemin , Chao Yanjie , Yang Ruifu , Cui Yujun , Martinez-Urtaza Jaime , Wang Hui , Falush Daniel
Published: June 2024

While the importance of spontaneous mutation and gene acquisition in the emergence and adaptive evolution of microbial pathogens is well recognized, the role of gene loss remains underexplored. Here, by large-scale phylogenomic analysis of 8,684 global isolates, we reconstructed the origin and evolutionary dynamics of the pandemic clone (PC) ofVibrio parahaemolyticus, the leading cause of seafood-associated infections worldwide. As has also been observed for the pandemic lineage ofV. cholerae, there was an ‘explosive’ burst of gene and genomic island acquisition during the emergence of the clone followed by divergence into distinct, successive sublineages mediating independent waves of cross-country transmission. InV. parahaemolyticus,a recent global wave succession event has been driven by gene-loss in the putrescine utilization (Puu) pathway, which confers phenotypic advantages related to environmental adaptation (enhanced biofilms) and human transmission (increased cell adhesion and intestinal colonization, reduced virulence in an animal model and milder clinical symptoms in humans), aligning with the trade-off hypothesis of pathogen virulence evolution. We identify similar lineage-specific Puu-gene-loss across multiple bacterial genera, with effects on biofilm and adhesion replicated inV. choleraeandE. coli, suggesting convergent evolution and universal mechanisms across bacteria. Our findings provide a paradigm of adaptative evolution by gene loss in a pandemic pathogen.
Chemical signatures delineate heterogeneous amyloid plaque populations across the Alzheimer’s disease spectrum
Authors: Koutarapu Srinivas , Ge Junyue , Dulewicz Maciej , Srikrishna Meera , Szadziewska Alicja , Wood Jack , Blennow Kaj , Zetterberg Henrik , Michno Wojciech , Ryan Natalie S , Lashley Tammaryn , Savas Jeffrey , Schöll Michael , Hanrieder Jörg
Published: June 2024

Amyloid plaque deposition is recognized as the primary pathological hallmark of Alzheimer’s disease(AD) that precedes other pathological events and cognitive symptoms. Plaque pathology represents itself with an immense polymorphic variety comprising plaques with different stages of amyloid fibrillization ranging from diffuse to fibrillar, mature plaques. The association of polymorphic Aβ plaque pathology with AD pathogenesis, clinical symptoms and disease progression remains unclear. Advanced chemical imaging tools, such as functional amyloid microscopy combined with MALDI mass spectrometry imaging (MSI), are now enhanced by deep learning algorithms. This integration allows for precise delineation of polymorphic plaque structures and detailed identification of their associated Aβ compositions. We here set out to make use of these tools to interrogate heterogenic plaque types and their associated biochemical architecture. Our findings reveal distinct Aβ signatures that differentiate diffuse plaques from fibrilized ones, with the latter showing substantially higher levels of Aβx-40. Notably, within the fibrilized category, we identified a distinct subtype known as coarse-grain plaques. Both in sAD and fAD brain tissue, coarse grain plaques contained more Aβx-40 and less Aβx-42 compared with cored plaques. The coarse grain plaques in both sAD and fAD also showed higher levels of neuritic content including paired helical filaments (PHF-1)/phosphorylated phospho Tau-immunopositive neurites. Finally, the Aβ peptide content in coarse grain plaques resembled that of vascular Aβ deposits (CAA) though with relatively higher levels of Aβ1-42 and pyroglutamated Aβx-40 and Aβx-42 species in coarse grain plaques. This is the first of its kind study on spatialin situbiochemical characterization of different plaque morphotypes demonstrating the potential of the correlative imaging techniques used that further increase the understanding of heterogeneous AD pathology. Linking the biochemical characteristics of amyloid plaque polymorphisms with various AD etiologies and toxicity mechanisms is crucial. Understanding the connection between plaque structure and disease pathogenesis can enhance our insights. This knowledge is particularly valuable for developing and advancing novel, amyloid-targeting therapeutics.
Small molecule NS11021 promotes BK channel activation by increasing inner pore hydration
Authors: Nordquist Erik B. , Jia Zhiguang , Chen Jianhan
Published: June 2024

The Ca2+and voltage-gated big potassium (BK) channels are implicated in various diseases including heart disease, asthma, epilepsy and cancer, but remains an elusive drug target. A class of negatively charged activators (NCAs) have been demonstrated to promote the activation of several potassium channels including BK channels by binding to the hydrophobic inner pore; yet the underlying molecular mechanism of action remains poorly understood. In this work, we analyze the binding mode and potential activation mechanism of a specific NCA named NS11021 using atomistic simulations. The results show that NS11021 binding to the pore in deactivated BK channels is nonspecific and dynamic. The binding free energy of -8.3±0.7 kcal/mol (KD= 0.3-3.1 μM) calculated using umbrella sampling agrees quantitatively with the experimental EC50 range of 0.4-2.1 μM. The bound NS11021 remains dynamic and is distal from the filter to significantly impact its conformation. Instead, NS11021 binding significantly enhances the pore hydration due to the charged tetrazol-phenyl group, thereby promoting the opening of the hydrophobic gate. We further show that the free energy barrier to K+permeation is reduced by ∼3 kcal/mol regardless of the binding pose, which could explain the ∼62-fold increase in the intrinsic opening of BK channels measured experimentally. Taken together, these results support that the molecular mechanism of NS11021 derives from increasing the hydration level of the conformationally closed pore, which does not depend on specific binding and likely explains the ability of NCAs to activate multiple K+channels.
Stability and causality of rest frame modes in second-order spin hydrodynamics
Authors: Daher Asaad , Florkowski Wojciech , Ryblewski Radoslaw , Taghinavaz Farid
Published: June 2024

We analyze the low- and high-momentum rest frame modes in the second-order spin hydrodynamics and check the asymptotic causality of the theory. A truncation scheme of the Israel-Stewart formalism derived in our earlier work is proposed that extends the minimal causal formulation. It consists of altogether 40 interconnected relaxation-type dynamical equations—16 (24) of them correspond to the independent components of the energy-momentum (spin) tensor. Similarly to previous studies, we find that the stability of the perturbations and asymptotic causality require using the spin equation of state that satisfies the generalized Frenkel condition demanding that the “electric” and “magnetic” components of the spin density tensor have opposite signs. For low-momentum modes this behavior is similar to that found earlier for the first-order (Navier-Stokes) spin hydrodynamics.

Published by the American Physical Society
2024
Constraints on variation of the weak scale from big bang nucleosynthesis
Authors: Burns Anne-Katherine , Keus Venus , Sher Marc , Tait Tim M. P.
Published: June 2024

Recently, the EMPRESS Collaboration has included new data in the extraction of the primordial He4 abundance from big bang nucleosynthesis (BBN), resulting in a determination that differs from the previous value and from theoretical expectations. There have been several studies attempting to explain this anomaly which involve variation of fundamental constants between the time of BBN and the present. Since the Higgs vacuum expectation value (vev) is the only dimensionful parameter in the Standard Model and it is already known to vary during the electroweak phase transition, we consider the possibility that the vev is slightly different during BBN compared to its present value. A modification of the vev changes not only particle masses but also affects, through mass thresholds, the QCD confinement scale. We use the recently developed yordial program to study this variation and its impact on the He4 and deuterium abundances. We find that bounds on |δv/v| are approximately 0.01, and that the EMPRESS result can be explained within 2σ if 0.008<δv/v<0.02, but at the cost of worsening the current 2σ discrepancy in the deuterium abundance to over 3σ.

Published by the American Physical Society
2024
Spinor-helicity representations of particles of any mass in
dS4
and
AdS4
spacetimes
Authors: Basile Thomas , Joung Euihun , Mkrtchyan Karapet , Mojaza Matin
Published: June 2024

The spinor-helicity representations of massive and (partially) massless particles in four-dimensional (anti–)de Sitter (A)dS spacetime are studied within the framework of the dual pair correspondence. We show that the dual groups (also known as “little groups”) of the anti–de Sitter and de Sitter groups are, respectively, O(2N) and O*(2N). For N=1, the generator of the dual algebra so(2)≅so*(2)≅u(1) corresponds to the helicity operator, and the spinor-helicity representation describes massless particles in (A)dS4. For N=2, the dual algebra is composed of two ideals, s and mΛ. The former ideal s≅so(3) fixes the spin of the particle, while the mass is determined by the latter ideal mΛ, which is isomorphic to so(2,1), iso(2), or so(3) depending on the cosmological constant being positive, zero, or negative. In the case of a positive cosmological constant, namely dS4, the spinor-helicity representation contains all massive particles corresponding to the principal series representations and the partially massless particles corresponding to the discrete series representations leaving out only the light massive particles corresponding to the complementary series representations. The zero and negative cosmological constant cases, which had been addressed in earlier references, are also discussed briefly. Finally, we consider the multilinear form of helicity spinors invariant under (A)dS group, which can serve as the (A)dS counterpart of the scattering amplitude, and discuss technical differences and difficulties of the (A)dS cases compared to the flat spacetime case.

Published by the American Physical Society
2024
Coupled cluster method tailored with quantum computing
Authors: Erhart Luca , Yoshida Yuichiro , Khinevich Viktor , Mizukami Wataru
Published: June 2024

Introducing an active space approximation is inevitable for the quantum computations of chemical systems. However, this approximation ignores the electron correlations related to nonactive orbitals. Here, we propose a computational method for correcting quantum computing results using a well-established classical theory called coupled cluster theory. Our approach efficiently extracts the quantum state from a quantum device by computational basis tomography. The extracted expansion coefficients of the quantum state are embedded into the coupled cluster ansatz within the framework of the tailored coupled cluster method. We demonstrate the performance of our method by verifying the potential energy curves of LiH, H2O, and N2 with a correlation-energy correction scheme. Our method demonstrates reasonable potential energy curves even when the standard coupled cluster fails. The sufficient numbers of measurements for tomography were also investigated. Furthermore, this method successfully estimated the activation energy of the Cope rearrangement reaction of 1,5-hexadiene together with perturbative triples correction. These demonstrations suggest that our approach has the potential for practical quantum chemical calculations using quantum computers.

Published by the American Physical Society
2024
Probing molecular spectral functions and unconventional pairing using Raman spectroscopy
Authors: Diessel Oriana K. , von Milczewski Jonas , Christianen Arthur , Schmidt Richard
Published: June 2024

An impurity interacting with an ultracold Fermi gas can form either a polaron state or a dressed molecular state, the molaron, in which the impurity forms a bound state with one gas particle. This molaron state features rich physics, including a negative effective mass around unitarity and a first-order transition to the polaron state. However, these features have remained so far experimentally inaccessible. In this work we show theoretically how the molaron state can be directly prepared experimentally even in its excited states using Raman spectroscopy techniques. Initializing the system in the ultrastrong coupling limit, where the binding energy of the molaron is much larger than the Fermi energy, our protocol maps out the momentum-dependent spectral function of the molecule. Using a diagrammatic approach we furthermore show that the molecular spectral function serves as a direct precursor of the elusive Fulde-Ferell-Larkin-Ovchinnikov phase, which is realized for a finite density of fermionic impurity particles. Our results pave the way to a systematic understanding of how composite particles form in quantum many-body environments and provide a basis to develop new schemes for the observation of exotic phases of quantum many-body systems.

Published by the American Physical Society
2024
180 °-twisted bilayer
ReSe2
as an artificial noncentrosymmetric semiconductor
Authors: Akatsuka S. , Sakano M. , Yamamoto T. , Nomoto T. , Arita R. , Murata R. , Sasagawa T. , Watanabe K. , Taniguchi T. , Mitsuishi N. , Kitamura M. , Horiba K. , Sugawara K. , Souma S. , Sato T. , Kumigashira H. , Shinokita K. , Wang H. , Matsuda K. , Masubuchi S. , Machida T. , Ishizaka K.
Published: June 2024

We have fabricated a 180 °-twisted bilayer ReSe2 by stacking two centrosymmetric monolayer ReSe2 flakes in opposite directions, which is expected to cause the loss of spatial inversion symmetry. We successfully observed spatial inversion-symmetry breaking, in contrast to the monolayer and natural bilayer ReSe2 by the second harmonic generation. ARPES measurements further revealed emergent band dispersions in the 180 °-twisted bilayer ReSe2, distinct from those of the monolayer ReSe2 used in its fabrication. The band calculation shows the finite lifting of spin degeneracy (∼50 meV) distinct from natural monolayer and bilayer ReSe2, which demonstrates that the spin-momentum locked state leading to Berry curvature related phenomena can be realized even with the stacking of centrosymmetric monolayers.

Published by the American Physical Society
2024
Asymptotic generalization errors in the online learning of random feature models
Authors: Worschech Roman , Rosenow Bernd
Published: June 2024

Deep neural networks are widely used prediction algorithms whose performance often improves as the number of weights increases, leading to over-parametrization. We consider a two-layered neural network whose first layer is frozen while the last layer is trainable, known as the random feature model. We study over-parametrization in the context of a student-teacher framework by deriving a set of differential equations for the learning dynamics. For any finite ratio of hidden layer size and input dimension, the student cannot generalize perfectly, and we compute the non-zero asymptotic generalization error. Only when the student's hidden layer size is exponentially larger than the input dimension, an approach to perfect generalization is possible.

Published by the American Physical Society
2024
Electronic bonding transitions in oxide glass above two megabar pressures
Authors: Kim Yong-Hyun , Chow Paul , Xiao Yuming , Shen Guoyin , Lee Sung Keun
Published: June 2024

Inelastic x-ray scattering (IXS) of B2O3 glass up to ∼2.2 Mbar reveals electronic bonding transitions in oxide glasses. B -edge IXS identifies the high-energy feature above ∼1.4 Mbar and a gradual increase in its intensity toward ∼2.2 Mbar, indicating the formation of hypervalent boron via electron polarization to oxygen atoms. The pressure-driven high energy shifts in O -edge IXS indicate pronounced electronic dispersion that increases upon densification of amorphous oxides above ∼2 Mbar. The extent of the energy shifts and enhanced polarization correlate with increasing atomic radius of cation in oxide glass, establishing the role of cation radius in electronic structures of amorphous oxides under compression. The results elucidate the electronic mechanisms behind the structural transformation in low- oxide glasses, where transitions to highly coordinated cations are hindered well above 1 Mbar, providing the origin of incompressibility of low- amorphous oxide under multi-Mbar compression.

Published by the American Physical Society
2024
Somebody's watching me: boundary turbulence and its impact on employee engagement
Authors: Lemon Laura L. , Bawole Claudia , Brinson Nancy H. , Amini Bahareh
Published: June 2024

Purpose

The purpose of this paper is to use the concept of boundary turbulence from Communication Privacy Management (CPM) theory to better understand how employee monitoring impacts employee engagement. This study is one of the first in corporate communication to combine the frameworks of CPM and employee engagement to better understand employee experiences.

Design/methodology/approach

To answer the research question, we conducted an online, open-ended survey that asked 633 participants to provide feedback regarding being monitored at work and how these experiences impacted their engagement with their employer.

Findings

This study sought to understand how boundary turbulence occurs in relation to employee engagement when employees are monitored at work. In total, four examples of boundary turbulence were illustrated in the data: employer monitoring creates distrust; employees find ways to resist being monitored; monitoring doesn’t accurately capture employee engagement; and monitoring leads to disengagement.

Originality/value

The findings from this study lead to important conclusions regarding what happens when employees experience boundary turbulence, and how it relates to employee engagement. This study illustrates how employee monitoring is interpreted as an attempt to control employees, which can lead to distrust and negatively impact employee engagement. Furthermore, boundary turbulence can threaten psychological safety and presence, which can cultivate employee disengagement. Therefore, employees may seek out ways to actively resist, which reiterates that internal publics are distinctive, active, and agentic audiences that cannot be forgotten or assumed.
An optimal threshold for over-indebtedness: a study on the discrepancy between subjective and objective debt burdens
Authors: Bialowolski Piotr , Kowalski Ryszard , Wałęga Agnieszka , Wałęga Grzegorz
Published: June 2024

Purpose

The study aims to explore the discrepancy between the subjective and objective debt burdens across various household socio-demographic and debt characteristics. Additionally, it seeks to establish an optimal debt service-to-income ratio (DSTI) threshold for identifying over-indebtedness.

Design/methodology/approach

This study utilized a sample of 1,004 respondents from a nationwide survey conducted among Polish indebted households. A discrepancy ratio (DR) measure was proposed to evaluate the divergence between subjective and objective over-indebtedness. Binary logistic regression was employed to estimate the probability of being subjectively and objectively over-indebted, as well as the discrepancy between the two measures of over-indebtedness. The study also employed numerical simulations to determine the optimal DSTI threshold for identifying over-indebted households in general and based on their socio-economic characteristics.

Findings

The study established a debt service-to-income ratio (DSTI) threshold of 20% to minimize the discrepancy between subjective and objective debt burden, which is lower than thresholds found in other studies aimed at identifying over-indebted households. Age, number of loans, self-perceived needs satisfaction and type of debt were identified as significant socio-economic and debt-related determinants of over-indebtedness. Household socio-economic and debt-related characteristics significantly influence the threshold for identifying over-indebtedness using DSTI. It can vary widely, ranging from as low as 11% for well-educated women with multiple loan commitments to 43.7% for young males with vocational education, high incomes and originating from households with four or more members.

Originality/value

The paper proposes a more comprehensive approach to debt burden analysis by introducing a new methodology for determining a debt service-to-income (DSTI) threshold that could serve as a measure of over-indebtedness based on the discrepancy between subjective and objective over-indebtedness. It also emphasizes the significance of socio-economic and debt-related factors in evaluating subjective and objective over-indebtedness.
Land tenure conflicts in forest areas: obstacles to rejuvenation of small-scale oil palm plantations in Indonesia
Authors: Mustofa Riyadi , Syahza Almasdi , Manurung Gulat Mendali Emas , Nasrul Besri , Afrino Rino , Siallagan Eko Jaya
Published: June 2024

Purpose

This study aims to investigate the problems small-scale oil palm plantations in Indonesia’s forest areas face and the government policies addressing them.

Design/methodology/approach

Survey and data collection were used to determine the socioeconomic, environmental, legal and governance problems related to the development of smallholder plantations. Information was obtained from the respondents via a rapid rural appraisal approach.

Findings

The potential land for potential participants in the community oil palm rejuvenation programme is a forest area of 1,628,749.60 ha. Owing to its legal dimensions and unsustainable land management, the rejuvenation regulatory programme has not reached independent farmers.

Research limitations/implications

The use of plantation space beyond its designation hinders the government’s goal of accelerating the rejuvenation programme. The problems regarding the accumulation of forest area result in low achievement of the annual rejuvenation target in Riau Province (21%–25%). The authors present solutions to resolve land ownership conflicts and implement strategic policies to ensure the sustainable development of such plantations.

Originality/value

The authors introduce a conflict–resolution model for small-scale smallholder oil palm plantations to resolve the problems of forest area claims unaddressed in the Indonesian Job Creation Law. Land conflict resolution is categorised into five typologies: oil palm plantations with business permits; those without a forestry permit and subject to administrative sanctions; business activities in forest areas without forestry permits; resolving non-conformities in the progress of land or management controlled and used in forest areas prior to their designation by removing land parcels through modifying the forest area boundaries; and the settlement for farmers without cultivation registration certificates but have established plantations and whose land tenure can be proven.
The morphology of urban tourism space (case: Malioboro Main Street as cosmological Axis of Yogyakarta city, Indonesia)
Authors: Ayudya Diana , Nuryanti Wiendu , Roychansyah Muhammad Sani
Published: June 2024

Purpose

This study aims to analyze the morphological landscape of the urban tourism spaces in the Malioboro Main Street area to predict its future development and to assist in creating effective regional planning policies.

Design/methodology/approach

This study uses qualitative grounded theory, typo morphological analysis and place-centered mapping techniques.

Findings

From the observation, it was found that each element of the city image area has different components of the urban tourism space’s morphology. The urban tourism spaces in Malioboro Main Street are distributed in a centered, linear and scattered pattern, with zones dedicated to shopping, cultural experiences and cuisine. The specific elements of each zone, such as attractions, accommodations or amenities, determine the type of tourism offered, such as cultural, shopping and culinary tourism.

Research limitations/implications

The study presented here may serve as a helpful guide for regulating and organizing policies that can form a sound basis for policy formulation. It mainly pertains to planning and structuring the Malioboro Main Street area, which currently needs a well-conceived urban tourism landscape development concept.

Practical implications

This study will have practical implications in projecting tourism development in the area through planning and structuring. The study can also be used as a basis and guideline for controlling, organizing and determining regulations and policies, ultimately serving as a wise foundation for policy formulation, particularly in planning and structuring the Cosmological Axis area, especially the Malioboro area.

Originality/value

The discussion of morphology is mainly limited to macro or micro scales, while the discussion of tourism space is generally limited to conceptual development. Conversely, this study aims to explore the unique landscape morphology of the Malioboro Main Street area, which serves as evidence of a productive space for urban tourism by typomorphological analysis through the approach of urban landscape elements, tourism elements and its activities. Thus, it may complement previous studies in urban areas dominated by tourism.
Influence of operating parameters on the silt erosion performance of bare and coated SS304 steel
Authors: Kumar Rajesh , Kumar Satish , Mudgal Deepa
Published: June 2024

Purpose

The purpose of this paper is to investigate the silt erosion performance of Bare, 75%Cr2O3 + 25%Al2O3 and 85%Cr2O3 + 15Al2O3-coated SS304 under various control parameters such as rotation speed, concentration of silt and particle size of silt used for making slurry. This can provide insight for using chromia and alumina-based coatings for hydro-turbines.

Design/methodology/approach

Taguchi approach was used to identify the effect of three input parameters on the bare and coated alloys. L16 orthogonal array is used for determining the signal-to-noise (S/N) ratio for each process parameter. For each level of parameters taken into consideration about the erosion wear, the arithmetic mean of the S/N ratio is calculated. On the essence of the results of S/N ratios, it is possible to determine the effect of the most dominating parameters of the erosion wear.

Findings

Results show that the erosion increases with an increase in silt concentration (Wt.%). It has been analyzed that the rotational speed has the most significant effect followed by the particle size and concentration on erosion wear for all uncoated and coated SS-304 samples. Maximum resistance to erosion is provided by 85%Cr2O3 + 15%Al2O3. The least erosion wear for process parameters has occurred at the optimal parametric combination of rotational speed (N) = 415 rev/min, concentration (C) = 15 Wt.% and particle size range as <53 µm for uncoated and coated stainless steel.

Originality/value

The study clearly shows the silt erosion performance of chromia and alumina coatings of different compositions at different input parameters.

Peer review

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-01-2024-0028/