bluuebunny/crossref_metadata_2025 huggingface dataset:
Dementia risk factors in former contact sports participants: prospective cohort study
Authors: Batty G. David , Bell Steven , Kujala Urho M. , Sarna Seppo J. , Kaprio Jaakko
Published: January 2024

Background

The elevated dementia incidence in retired contact sport participants might be explained by a higher prevalence of established risk factors for the disease relative to the general population.

Methods

In this cohort study, former elite participants active between 1920 and 1965 in soccer (N=303), boxing (N=281), and wrestling (N=318) were recruited using sports yearbooks and records of sports associations. Men in a population control group were identified using records from a compulsory medical examination (N=1712). All study members were linked to hospital registers (1970-2015) and self-completion questionnaires were circulated (1985, 1995) from which we captured data on nine established risk factors for dementia: hypertension and diabetes status, alcohol intake, loneliness, depressive symptoms, cigarette smoking, body weight, educational attainment, and physical activity.

Results

There was little suggestion that former participants in contact sports had a higher prevalence of dementia risk factors relative to the general population. Rather, the balance of evidence was for more favourable risk factor levels in former athletes, as was particularly evident for ever having smoked cigarettes (range in odds ratios [95% confidence interval]: 0.32 [0.21, 0.48] for wrestling to 0.52 [0.36, 0.75] for soccer) and leisure-time physical activity (range in beta coefficients [95% confidence interval]: 1.34 [0.66, 2.02] for soccer to 1.80 [1.07, 2.52] for boxing).

Conclusions

The increased dementia rates in retired contact sport participants evident in epidemiological studies is unlikely to be explained by the risk factors examined here. This implicates other characteristics of contact sports, including a history of repeated head impact.
Beyond Hypertension: Examining Variable Blood Pressure’s Role in Cognition and Brain Structure
Authors: Morrison Cassandra , Oliver Michael D. , Kamal Farooq , Dadar Mahsa ,   the Alzheimer’s Disease Neuroimaging Initiative
Published: January 2024

Structured Abstract

Importance

Hypertension is a known risk factor for cognitive decline and structural brain changes in aging and dementia. In addition to high blood pressure (BP), individuals may also experience variable BP, meaning that their BP fluctuates between normal and high. It is currently unclear what the effects of variable BP are on cognition and brain structure.

Objective

To investigate the influence of BP on cognition and brain structure in older adults.

Design, Setting, and Participants

This longitudinal cohort study included data from the Rush Alzheimer’s Disease Center Research Resource Sharing Hub (RUSH) and the Alzheimer’s Disease Neuroimaging Initiative (ADNI). Participants from the two studies were included if they had BP measurements and either cognitive scores or MRI scans from at least one visit.

Main Outcomes and Measures

Longitudinal gray matter, white matter, white matter hyperintensity volumes, postmortem neuropathology information, as well as cognitive test scores.

Results

A total of 4606 participants (3429 females, mean age = 76.8) with 32776 follow-ups (mean = 7 years) from RUSH and 2114 participants (1132 females, mean age = 73.3) with 9827 follow-ups (mean = 3 years) from ADNI were included in this study. Participants were divided into one of three groups: 1) normal BP, high BP, or variable BP. Older adults with variable BP exhibited the highest rate of cognitive decline followed by high BP and then normal BP. Increased GM volume loss and WMH burden was also observed in variable BP compared to high and normal BP. With respect to post-mortem neuropathology, both variable and high BP had increased severities compared to normal BP. Importantly, results were consistent across the RUSH and ADNI participants, supporting the generalizability of the findings.

Conclusion and Relevance

Limited research has examined the long-term impact of variable BP on cognition and brain structure. These findings show the importance that both high and variable BP have on cognitive decline and structural brain changes. Structural damages caused by variable BP may reduce resilience to future dementia-related pathology and increased risk of dementia. Improved treatment and management of variable BP may help reduce cognitive decline in the older adult population.
Temporal and spatial dynamics within the fungal microbiome of grape fermentation
Authors: Onetto Cristobal A. , Ward Chris M. , Van Den Heuvel Steven , Hale Laura , Cuijvers Kathleen , Borneman Anthony R.
Published: January 2024

Wine fermentation is a highly complex and competitive environment, imposing harsh selective pressures on fungal community ecology and diversity. The composition of fungal communities inhabiting the surface of grapes will directly impact fermentation progression, wine quality, and contribute to the distinctiveness between wines from different geographical regions. Despite this, the extent of microbial community diversity between geographies, termed ‘microbial terroir,’ remains highly debated. We amassed a large survey of grape spontaneous ferments over six years, encompassing 3105 fungal microbiomes across 14 geographically separated grape-growing regions, and nine grape cultivars. Investigation into the biodiversity of these ferments identified that few high abundance genera form the core of the initial grape microbiome. In line with previous studies, various consistent taxa were linked to specific geographical locations and grape varieties. However, these taxa accounted for a small portion of the overall diversity in the dataset. Through unsupervised clustering, we identified three distinct community types in the grape fungal microbiome, each exhibiting variations in the abundance of key genera. Analysing ferments across temporal and spatial scales revealed significant differences in species richness and compositional heterogeneity between wineries and grape growing regions. However, microbial communities were transient between years in the same winery, regularly transitioning between the three broad community types. We then investigated microbial community composition throughout the fermentative process and observed that initial microbial community composition is predictive of the diversity during the early stages of fermentation, withHanseniaspora uvarumdetected as the main non-Saccharomycesspecies within this large cohort of samples. Our results help to formulate a clear understanding of the spatial and temporal characteristics of the grape juice fungal microbiome and suggest that these communities are mainly defined by the grape niche and in a minor way shaped by local environmental conditions.
Sox9links biliary maturation to branching morphogenesis
Authors: Hrncir Hannah R , Bombin Sergei , Goodloe Brianna , Hogan Connor B , Jadi Othmane , Gracz Adam D
Published: January 2024

Branching morphogenesis couples cellular differentiation with development of tissue architecture. Intrahepatic bile duct (IHBD) morphogenesis is initiated with biliary epithelial cell (BEC) specification and eventually forms a heterogeneous network of large ducts and small ductules. Here, we show thatSox9is required for developmental establishment of small ductules. IHBDs emerge as a webbed structure by E15.5 and undergo morphological maturation through 2 weeks of age. Developmental knockout ofSox9leads to decreased postnatal branching morphogenesis, manifesting as loss of ductules in adult livers. In the absence ofSox9, BECs fail to mature and exhibit elevated TGF-β signaling and Activin A. Activin A induces developmental gene expression and morphological defects in BEC organoids and represses ductule formation in postnatal livers. Our data demonstrate that adult IHBD morphology and BEC maturation is regulated by theSox9-dependent formation of precursors to ductules during development, mediated in part by downregulation of Activin A.
Gaze and Arrows: does the Gaze Following Patch in the posterior temporal cortex differentiate social and symbolic spatial cues?
Authors: Görner Marius , Ramzanpour Hamidreza , Dicke Peter , Thier Peter
Published: January 2024

TheGaze Following Patch(GFP) is located in the posterior temporal cortex and has been described as a cortical module dedicated to processing other people’s gaze direction in a domain-specific manner. Thus, it appears to be the neural correlate of Baron-Cohen’s Eye-Direction Detector (EDD) which is one of the core modules in hisMindreading System- a neurocognitive model for theTheory of Mindconcept. Inspired by Jerry Fodor’s ideas on the modularity of the mind, Baron-Cohen proposed that, among other things, the individual modules are domain-specific. In the case of the EDD this means that it exclusively processes eye-like stimuli to extract gaze direction and that other stimuli, that may carry directional information as well, are processed elsewhere. If the GFP is indeed EDD’s neural correlate it must meet this expectation. To test this, we compared the GFP’s BOLD activity during gaze-direction following with the activity during arrow-direction following. Contrary to the expectation based on the assumption of domain specificity we did not find a differentiation between gaze and arrow-direction following. In fact, we were not able to reproduce the GFP as presented in previous studies. A possible explanation is that in the present study – unlike previous work –, the gaze stimuli did not contain an obvious change of direction that represented a visual motion. Hence, the critical stimulus component responsible for the identification of the GFP in previous experiments might have been visual motion.
Inflamed Natural Killer cells with adhesion defects are associated with a poor prognosis in Multiple Myeloma
Authors: Blanquart Eve , Ekren Rüçhan , Rigaud Bineta , Joubert Marie-Véronique , Baylot Virginie , Daunes Hélène , Cuisinier Marine , Villard Marine , Carrié Nadège , Mazzotti Céline , Baylot Virginie , Lucca Liliana E. , Perrot Aurore , Corre Jill , Walzer Thierry , Avet-Loiseau Hervé , Axisa Pierre-Paul , Martinet Ludovic
Published: January 2024

The promising results obtained with immunotherapeutic approaches for multiple myeloma (MM) call for a better stratification of patients based on immune components. The most pressing being cytotoxic lymphocytes such as Natural Killer (NK) cells that are mandatory for MM surveillance and therapy. In this study, we performed a single cell RNA sequencing analysis of NK cells from 10 MM patients and 10 age/sex matched healthy donors (HD) that revealed important transcriptomic changes in NK cell landscape affecting both the bone marrow and peripheral blood compartment. The frequency of mature cytotoxic “CD56dim” NK cell subsets was reduced in MM patients at the advantage of late-stage NK cell subsets expressing NFκB and IFN-I inflammatory signatures. These NK cell subsets accumulating in MM patients were characterized by a low CD16 and CD226 expression and poor cytotoxic functions. MM CD16/CD226loNK cells also had adhesion defects with reduced LFA-1 integrin activation and actin polymerization that may account for their limited effector functionsin vitro. Finally, analysis of BM infiltrating NK cells in a retrospective cohort of 177 MM patients from the IFM 2009 trial demonstrated that a high frequency of NK cells and their low CD16 and CD226 expression were associated with a shorter overall survival. Thus, CD16/CD226loNK cells with reduced effector functions accumulate along MM development and negatively impact patients’ clinical outcome. Given the growing interest in harnessing NK cells to treat myeloma, this improved knowledge around MM-associated NK cell dysfunction will stimulate the development of more efficient immunotherapeutic drugs against MM.

Scientific category:Lymphoid Neoplasia; Immunobiology and Immunotherapy.

KEY POINTS

MM patients have increased CD16/CD226lowNK cell subsets characterized by “inflammatory” signatures and reduced effector functions.

The frequency of CD16/CD226lowNK cells correlate with MM patient clinical outcome
DORA: an interactive map for the visualization and analysis of ancient human DNA and associated data
Authors: Harris Keith D. , Greenbaum Gili
Published: January 2024

The ability to sequence ancient genomes has revolutionized the way in which we study evolutionary history by providing access to the most important aspect of evolution — time. Until recently, studying human demography, ecology, biology, and history using population genomic inference relied on contemporary genomic datasets. Over the past decade, the availability of human ancient DNA (aDNA) has increased rapidly, almost doubling every year, opening the way for spatiotemporal studies of ancient human populations. However, the multidimensionality of aDNA, with genotypes having temporal, spatial and genomic coordinates, and the need to integrate multiple sources of data, poses a challenge for developing meta-analyses pipelines. To address this challenge, we developed a publicly-available interactive tool,DORA, which integrates multiple data types, genomic and non-genomic, in a unified interface. This web-based tool allows users to browse sample metadata along with additional layers of information, such as population structure, climatic data, and unpublished samples. Users can then perform analyses on genotypes of these samples, or export sample subsets for external analyses.DORAintegrates analyses and visualizations in a single intuitive interface, resolving the technical issues of combining datasets from different sources and formats, and allowing researchers to focus on analysis and the scientific questions that can be addressed through analysis of aDNA datasets.
A human papillomavirus 16 E2-TopBP1 dependent SIRT1-p300 acetylation switch regulates mitotic viral and human protein levels
Authors: Prabhakar Apurva T. , James Claire D. , Youssef Aya H. , Hossain Reafa A. , Hill Ronald D. , Bristol Molly L. , Wang Xu , Dubey Aanchal , Morgan Iain M.
Published: January 2024

An interaction between human papillomavirus 16 (HPV16) E2 and the cellular proteins TopBP1 and BRD4 is required for E2 plasmid segregation function. The E2-TopBP1 interaction promotes increased mitotic E2 protein levels in U2OS and N/Tert-1 cells, as well as in human foreskin keratinocytes immortalized by HPV16 (HFK+HPV16). SIRT1 deacetylation reduces E2 protein stability and here we demonstrate that increased E2 acetylation occurs during mitosis in a TopBP1 interacting dependent manner, promoting E2 mitotic stabilization. p300 mediates E2 acetylation and acetylation is increased due to E2 switching off SIRT1 function during mitosis in a TopBP1 interacting dependent manner, confirmed by increased p53 stability and acetylation on lysine 382, a known target for SIRT1 deacetylation. SIRT1 can complex with E2 in growing cells but is unable to do so during mitosis due to the E2-TopBP1 interaction; SIRT1 is also unable to complex with p53 in mitotic E2 wild type cells but can complex with p53 outside of mitosis. E2 lysines 111 and 112 are highly conserved residues across all E2 proteins and we demonstrate that K111 hyper-acetylation occurs during mitosis, promoting E2 interaction with Topoisomerase 1 (Top1). We also demonstrate that K112 ubiquitination promotes E2 proteasomal degradation during mitosis. The results present a model in which the E2-TopBP1 complex inactivates SIRT1 during mitosis and E2 acetylation on K111 by p300 increases, promoting interaction with Top1 that protects K112 from ubiquitination and therefore E2 proteasomal degradation.

Importance

Human papillomaviruses are causative agents in around 5% of all human cancers. While there are prophylactic vaccines that will significantly alleviate HPV disease burden on future generations, there are currently no anti-viral strategies available for the treatment of HPV cancers. To generate such reagents, we must understand more about the HPV life cycle, and in particular about viral-host interactions. Here we describe a novel mitotic complex generated by the HPV16 E2 protein interacting with the host protein TopBP1 that controls the function of the deacetylase SIRT1. The E2-TopBP1 interaction disrupts SIRT1 function during mitosis in order to enhance acetylation and stability of viral and host proteins. This novel complex is essential for the HPV16 life cycle and represents a novel anti-viral therapeutic target.
Elucidating ATP’s Role as Solubilizer of Biomolecular Aggregate
Authors: Sarkar Susmita , Gupta Saurabh , Mahato Chiranjit , Das Dibyendu , Mondal Jagannath
Published: January 2024

Proteins occurring in significantly high concentrations in cellular environments (over 100 mg/mL) and functioning in crowded cytoplasm, often face the prodigious challenges of aggregation which are the pathological hallmark of aging and are critically responsible for a wide spectrum of rising human diseases. Here we combine a joint-venture of complementary wet-lab experiment and molecular simulation to discern the potential ability of adenosine triphosphate (ATP) as solubilizer of protein aggregates. We show that ATP prevents both condensation of aggregation-prone intrinsically disordered protein Aβ40 and promotes dissolution of pre-formed aggregates. Computer simulation links ATP’s solubilizing role to its ability to modulate protein’s structural plasticity by unwinding protein conformation. We show that ATP is positioned as a superior biological solubilizer of protein aggregates over traditional chemical hydrotropes, potentially holding promises in therapeutic interventions in protein-aggregation related diseases. Going beyond its conventional activity as energy currency, the amphiphilic nature of ATP enables its protein-specific interaction that would enhance ATP’s efficiency in cellular processes.
Structural Basis of How MGME1 Processes DNA 5′ Ends to Maintain Mitochondrial Genome Integrity
Authors: Mao Eric Y.C. , Yen Han-Yi , Wu Chyuan-Chuan
Published: January 2024

Mitochondrial genome maintenance exonuclease 1 (MGME1) helps to ensure mitochondrial DNA (mtDNA) integrity by serving as an ancillary 5′ exonuclease for DNA polymerase γ. Curiously, MGME1 exhibits unique bidirectionalityin vitro, being capable of degrading DNA from either the 5′ or 3′ end. The structural basis of this bidirectionally and, particularly, how it processes DNA from the 5′ end to assist in mtDNA maintenance remains unclear. Here, we present a crystal structure of human MGME1 in complex with a 5′-overhang DNA, revealing that MGME1 functions as a rigid DNA clamp equipped with a single-strand-(ss)-selective arch, allowing it to slide on single-stranded DNA in either the 5′-to-3′ or 3′-to-5′ direction. Using a nuclease activity assay, we have dissected the structural basis of MGME1-derived DNA cleavage patterns in which the arch serves as a ruler to determine the cleavage site. We also reveal that MGME1 displays partial DNA-unwinding ability that helps it to better resolve 5′-DNA flaps, providing insights into MGME1-mediated 5′-end processing of nascent mtDNA. Our study builds on previously solved MGME1-DNA complex structures, finally providing the comprehensive functional mechanism of this bidirectional, ss-specific exonuclease.
Spatiotemporal visualization of DNA replication by click chemistry reveals bubbling of viral DNA in virion formation
Authors: Gomez-Gonzalez Alfonso , Burkhardt Patricia , Bauer Michael , Loehr Morten O. , Luedtke Nathan W. , Greber Urs F.
Published: January 2024

The organisation of human chromosomes reversibly changes in cell division, and irreversibly in apoptosis or erythropoiesis by DNA condensation and fragmentation processes. Yet, how viral replication in the nucleus affects host and viral chromatin organisation remains poorly understood. Here we used dual-color click chemistry to image human adenovirus DNA replication, demonstrating host chromatin compaction during active expansion of the viral replication compartment (VRC). Early-replicated viral DNA (vDNA) segregated from VRC and lost phospho-serine5-RNA Pol-II and viral DNA-binding protein (DBP), while late-replicated vDNA retained active RNA Pol-II, besides viral RNA-splicing and DNA-packaging proteins. Depending on replication and the assembly protein 52K, the late-stage VRCs gave rise to progeny by droplet formation of vDNA with GFP-tagged virion protein V into 52K biomolecular condensates. The study reveals distinct functions of early and late-replicated vDNA and provides insight into active and passive liquid phase separated zones conducive to selective genome packaging of nascent virions.
Long-horizon associative learning explains human sensitivity to statistical and network structures in auditory sequences
Authors: Benjamin Lucas , Sablé-Meyer Mathias , Fló Ana , Dehaene-Lambertz Ghislaine , Roumi Fosca Al
Published: January 2024

Networks are a useful mathematical tool for capturing the complexity of the world. In a previous behavioral study, we showed that human adults were sensitive to the high-level network structure underlying auditory sequences, even when presented with incomplete information. Their performance was best explained by a mathematical model compatible with associative learning principles, based on the integration of the transition probabilities between adjacent and non-adjacent elements with a memory decay. In the present study, we explored the neural correlates of this hypothesis via magnetoencephalography (MEG). Participants passively listened to sequences of tones organized in a sparse community network structure comprising two communities. An early difference (~150 ms) was observed in the brain responses to tone transitions with similar transition probability but occurring either within or between communities. This result implies a rapid and automatic encoding of the sequence structure. Using time-resolved decoding, we estimated the duration and overlap of the representation of each tone. The decoding performance exhibited exponential decay, resulting in a significant overlap between the representations of successive tones. Based on this extended decay profile, we estimated a long-horizon associative learning novelty index for each transition and found a correlation of this measure with the MEG signal. Overall, our study sheds light on the neural mechanisms underlying human sensitivity to network structures and highlights the potential role of Hebbian-like mechanisms in supporting learning at various temporal scales.
Critical states and anomalous mobility edges in two-dimensional diagonal quasicrystals
Authors: Duncan Callum W.
Published: January 2024

We study the single-particle properties of two-dimensional quasicrystals where the underlying geometry of the tight-binding lattice is crystalline but the on-site potential is quasicrystalline. We will focus on the two-dimensional (2D) generalized Aubry-André model which has a varying form to its quasiperiodic potential, through a deformation parameter and varied irrational periods of cosine terms, which allows a continuous family of on-site quasicrystalline models to be studied. We show that the 2D generalized Aubry-André model exhibits many single-particle mobility edges which we confirm for finite systems and supports critical states across large parameter regions. Critical states are neither fully localized nor extended. We observe that diagonal quasicrystalline models can support many energy intervals of critical states in the spectrum while stabilizing both localized and extended states in other energy intervals; we refer to these as anomalous mobility edges. We show that critical states are present independent of system size through a scaling analysis of the inverse participation ratio and that they are present in spectra that also contain extended and localized states, confirming that at least one anomalous mobility edge is present. Due to this, these models exhibit anomalous diffusion of initially localized states across the majority of parameter regions, including deep in the normally localized regime. The presence of critical states in large parameter regimes and throughout the spectrum will have consequences for the many-body properties of quasicrystals, including the formation of the Bose glass and the potential to host a many-body localized phase.

Published by the American Physical Society
2024
Rejection-free quantum Monte Carlo in continuous time from transition path sampling
Authors: Causer Luke , Sfairopoulos Konstantinos , Mair Jamie F. , Garrahan Juan P.
Published: January 2024

Continuous-time quantum Monte Carlo refers to a class of algorithms designed to sample the thermal distribution of a quantum Hamiltonian through exact expansions of the Boltzmann exponential in terms of stochastic trajectories which are periodic in imaginary time. Here, we show that for (sign-problem-free) quantum many-body systems with discrete degrees of freedom—such as spins on a lattice—this sampling can be done in a rejection-free manner using transition path sampling (TPS). The key idea is to converge the trajectory ensemble through updates where one individual degree of freedom is modified across all time while the remaining unaltered ones provide a time-dependent background. The ensuing single-body dynamics provides a way to generate trajectory updates exactly, allowing one to obtain the target ensemble efficiently via rejection-free TPS. We demonstrate our method on the transverse field Ising model in one and two dimensions, and on the quantum triangular plaquette (or Newman-Moore) model. We show that despite large autocorrelation times, our method is able to efficiently recover the respective quantum phase transition of each model. We also discuss the connection to rare event sampling in continuous-time Markov dynamics.

Published by the American Physical Society
2024
Tailoring energy barriers of Bloch-point-mediated transitions between topological spin textures
Authors: Li Yu , Zang Yuzhe , Chen Runze , Moutafis Christoforos
Published: January 2024

Magnetic skyrmions are nanoscale spin textures whose thermal stability originates from the nontrivial topology in nature. Recently, a plethora of topological spin textures have been theoretically predicted or experimentally observed, enriching the diversity of the skyrmionic family. In this work, we theoretically demonstrate the stabilities of various topological spin textures against homochiral states in chiral magnets, including chiral bobbers, dipole strings, and skyrmion tubes. They can be effectively classified by the associated topological Hall signals. Multiple transition paths are found among these textures, mediated by Bloch-point singularities, and the topological protection property here can be manifested by a finite energy barrier with the saddle point corresponding to the Bloch-point creation/destruction. By carefully modulating the local property of a surface, such as interfacial Dzyaloshinskii-Moriya interaction induced by breaking the structural symmetry, the energy landscape of a magnetic system can be tailored decisively. Significantly, the proposed scenario also enables the manipulation of stabilities and transition barriers of these textures, even accompanied by the discovery of ground-state chiral bobbers. This study may raise great expectations on the coexistence of topological spin textures as spintronics-based information carriers for future applications.

Published by the American Physical Society
2024
Electron-positron, parton-parton, and photon-photon production of
τ
-lepton pairs: Anomalous magnetic and electric dipole moments spin effects
Authors: Banerjee Sw. , Korchin A. Yu. , Richter-Was E. , Was Z.
Published: January 2024

Anomalous contributions to the electric and magnetic dipole moments of the τ lepton from new physics scenarios have brought renewed interest in the development of new charge-parity violating signatures in τ-pair production at Belle II energies, and also at higher energies of the Large Hadron Collider and the Future Circular Collider. In this paper, we discuss the effects of spin correlations, including transverse degrees of freedom, in the τ-pair production and decay. These studies include calculating analytical formulas, obtaining numerical results, and building semirealistic observables sensitive to the transverse spin correlations induced by the dipole moments of the τ lepton. The effects of such anomalous contributions to the dipole moments are introduced on top of precision simulations of e−e+→τ−τ+, qq¯→τ−τ+ and γγ→τ−τ+ processes, involving multibody final states. The τ decays are simulated along with radiative corrections, in particular electroweak box contributions of WW and ZZ exchanges are taken into account. Respective extensions of the Standard Model amplitudes and the reweighting algorithms are implemented into the Monte Carlo, which is used to simulate τ-pair production in e−e+ collisions, and the aupinner program, which is used to reweight events with τ pair produced in pp collisions.

Published by the American Physical Society
2024
Spatial imaging of proton via leading-twist nonskewed GPDs with basis light-front quantization
Authors: Kaur Satvir , Xu Siqi , Mondal Chandan , Zhao Xingbo , Vary James P. ,   BLFQ Collaboration
Published: January 2024

The internal image of the proton is unveiled by examining the generalized parton distributions (GPDs) at zero skewness, within the basis light-front quantized environment. Several distributions emerge when a quark is sampled with different currents depending upon the helicity arrangements of the active quark and the proton target. We investigate six of the eight leading-twist proton GPDs of the valence quarks, the helicity conserving distributions (H,E,H˜) and the helicity nonconserving (HT,ET,H˜T) distributions at skewness set to zero (ζ=0). We consider purely transverse momentum transfer and, hence, obtain results describe only the proton’s two-dimensional structure in the transverse plane. We present the Mellin moments of these distribution functions, where the first moment produces a form factor and the second Mellin moments help extract the information on partonic contributions to the hadronic angular momentum. We compare our results for the Mellin moments with those from lattice QCD and other approaches where available. We also present the GPDs in transverse position space.

Published by the American Physical Society
2024
Semantic segmentation of anomalous diffusion using deep convolutional networks
Authors: Qu Xiang , Hu Yi , Cai Wenjie , Xu Yang , Ke Hu , Zhu Guolong , Huang Zihan
Published: January 2024

Heterogeneous dynamics commonly emerges in anomalous diffusion with intermittent transitions of diffusion states but proves challenging to identify using conventional statistical methods. To effectively capture these transient changes of diffusion states, we propose a deep learning model (U-AnDi) for the semantic segmentation of anomalous diffusion trajectories. This model is developed with the dilated causal convolution (DCC), gated activation unit (GAU), and U-Net architecture. The study addresses two key subtasks related to trajectory segmentation and changepoint detection, concentrating on variations in diffusion exponents and dynamic models. Additionally, extended analyses are conducted on the segmentation of single-model trajectories, multistate biological trajectories, and anomalous diffusion with added correlation functions. By rationally designing comparative models and evaluating the performance of U-AnDi against these models, we discover that U-AnDi consistently outperforms other models across all segmentation tasks, thereby affirming its superiority in the field. This performance edge also sheds light on the interpretability of U-AnDi's core components: DCC, GAU, and U-Net. The clarity with which these components contribute to U-AnDi's success underscores their congruence with the intrinsic physics underlying anomalous diffusion. Furthermore, our model is examined using real-world anomalous diffusion data: the diffusion of transmembrane proteins on cell membrane surfaces, and the segmentation results are highly consistent with experimental observations. Our findings could offer a heuristic deep learning solution for the detection of heterogeneous dynamics in single-molecule/particle tracking experiments, and have the potential to be generalized as a universal scheme for time-series segmentation.

Published by the American Physical Society
2024
Revealing the Bonding Nature and Electronic Structure of Early-Transition-Metal Dihydrides
Authors: Kalha Curran , Ratcliff Laura E. , Colombi Giorgio , Schlueter Christoph , Dam Bernard , Gloskovskii Andrei , Lee Tien-Lin , Thakur Pardeep K. , Bhatt Prajna , Zhu Yujiang , Osterwalder Jürg , Offi Francesco , Panaccione Giancarlo , Regoutz Anna
Published: January 2024

Metal hydrides are potential candidates for applications in hydrogen-related technologies, such as energy storage, hydrogen compression, and hydrogen sensing, to name just a few. However, understanding the electronic structure and chemical environment of hydrogen within them remains a key challenge. This work presents a new analytical pathway to explore these aspects in technologically relevant systems using hard x-ray photoelectron spectroscopy (HAXPES) on thin films of two prototypical metal dihydrides: YH2−δ and TiH2−δ. By taking advantage of the tunability of synchrotron radiation, a nondestructive depth profile of the chemical states is obtained using core-level spectra. Combining experimental valence-band (VB) spectra collected at varying photon energies with theoretical insights from density functional theory (DFT) calculations, a description of the bonding nature and the role of d versus sp contributions to states near the Fermi energy are provided. Moreover, a reliable determination of the enthalpy of formation is proposed by using experimental values of the energy position of metal s-band features close to the Fermi energy in the HAXPES VB spectra.

Published by the American Physical Society
2024
How do green intellectual and co-creational capitals drive artificial intelligence innovation and green innovation in start-ups?
Authors: Almansour Mohammed
Published: January 2024

Purpose

This research examines the relationship between the green version of intellectual capital (IC) (measured through green versions of human, structural and relational capitals (GHC, GSC and GRC)), co-creational capital (CC), green innovation (GI), technological innovation (TI) (measured through artificial intelligence) and start-up competitive advantage (SCA).

Design/methodology/approach

An online questionnaire collected data from 275 participants. To test the hypotheses, the data were analyzed using SmartPLS.

Findings

The results confirmed the positive influence of GSC and CC on TI and GI, GRC with GI and that of GI and TI with SCA. The results also reveal that IC can influence innovation and describe how innovation can drive the competitive advantage (CA) of start-ups.

Research limitations/implications

This self-report study examines the associations by collecting data at one point in time, which results in methodological limitations regarding the generalization of the results. The second limitation is that the findings are limited to start-ups.

Originality/value

This research work examined a model that combined three components of green IC, customer capital, two forms of innovation and CA. These associations have not been previously examined yet can provide useful insight into what drives green and TIs and how they further influence competitiveness. This study provides unique inferences that improve the value of the literature on IC and innovation, using start-ups as context.
Mediating effect of absorptive capacity on the relationship between knowledge sharing and entrepreneurial orientation and the moderating role of opportunity recognition
Authors: Makhloufi Lahcene , Laghouag Abderrazak Ahmed , Ali Sahli Alhussain
Published: January 2024

Purpose

Knowledge sharing enables a firm’s absorptive capacity to reconfigure its dynamic capabilities to sense, track and recognise embryonic business opportunities. Entrepreneurial opportunity recognition triggers entrepreneurs to invest in and upgrade their knowledge practices to improve entrepreneurial performance. This study aims to examine the relationship between knowledge sharing and absorptive capacity on entrepreneurial orientation as well as the moderating effect of opportunity recognition and the mediating effect of absorptive capacity.

Design/methodology/approach

A quantitative cross-sectional research design was applied to data from Algerian small and medium-sized enterprise managers in middle- to top-management positions. The final analysis using smart PLS included 246 respondents.

Findings

Knowledge sharing positively influenced entrepreneurial orientation and absorptive capacity. In addition, the findings reveal that entrepreneurial orientation positively influences entrepreneurial performance, and opportunity recognition strengthens the relationship between entrepreneurial orientation and entrepreneurial performance. Entrepreneurial orientation and absorptive capacity have partial mediating effects.

Practical implications

This study focuses on how firms create and share developed knowledge to enable absorptive capacity to fit a level of entrepreneurial orientation. This study validates the vital impact of opportunity recognition as a leading motivation for entrepreneurial orientation. The results highlight an important area of research and suggest that firms should focus on knowledge sharing to boost entrepreneurial outcomes.

Originality/value

The notions of entrepreneurship, absorptive capacity and knowledge sharing are extended by building on dynamic capability theory. Knowledge sharing increases absorptive capacity, which drives superior entrepreneurial orientation outcomes.
Relationship building through informal gatherings and technology integrations: a case study
Authors: Gala Bhakti , Reyes Vanessa , Seifi Leili , Lamba Manika
Published: January 2024

Purpose

This case study aims to explore how to provide an informal space to connect members socially, informally and with peers, to provide opportunities for collaboration and informal conversation. The purpose is to analyze the use of technology to promote collaborations and networking within online professional settings.

Design/methodology/approach

In this case study, the authors particularly examine the initiatives as they contribute to the organization, which allows us to understand the interactions between information technology-related tools and online communication.

Findings

Successful engagement in informal gatherings was initiated through the planning and implementation with a focus on the following: thematic meetings, time management and participation.

Originality/value

The case study presents an analysis of the use of technology integration into the planning processes that were undertaken by a group of members to enhance informal gatherings for relationship building within a global community of members during the COVID-19 pandemic. The authors suggest ways of engaging users that could be used as a model for organizations alike.
Research across disciplines: influence of human resource management practices
Authors: Martín-Alcázar Fernando , Ruiz-Martínez Marta , Sánchez-Gardey Gonzalo
Published: January 2024

Purpose

This study aims to examine the connection between scholars' research performance and the multidisciplinary nature of their collaborative research. Furthermore, in response to mixed results regarding the effects of multidisciplinarity on research performance, this study explores how human resource management (HRM) practices may moderate this link.

Design/methodology/approach

The authors built a model based on the theoretical arguments and empirical evidence found in the review of diversity and HRM literature. The authors also performed a quantitative study based on a sample of scholars in the field of management. Different econometric estimations were used to test the proposed model.

Findings

The results of this empirical analysis suggest that multidisciplinary research has a non-linear effect on research performance. Certain HRM practices, such as development and collaboration, moderated the curvilinear relationship between multidisciplinarity and performance, displacing the optimum to allow higher performance at higher levels of multidisciplinary research.

Originality/value

The paper provides advances on previous works studying the curvilinear relationship between multidisciplinarity and the researchers' performance, confirming that multidisciplinarity is beneficial up to a threshold beyond which these benefits are attenuated. In addition, the findings shed light on important issues related to team-oriented HRM practices associated with the outcomes of multidisciplinary research.
Management learning in public healthcare during pandemics
Authors: Rosenbäck Ritva , Svensson Ann
Published: January 2024

Purpose

This study aims to explore the management learning during a long-term crisis like a pandemic. The paper addresses both what health-care managers have learnt during the COVID-19 pandemic and how the management learning is characterized.

Design/methodology/approach

The paper is based on a qualitative case study carried out during the COVID-19 pandemic at two different public hospitals in Sweden. The study, conducted with semi-structured interviews, applies a combination of within-case analysis and cross-case comparison. The data were analyzed using thematic deductive analysis with the themes, i.e. sensemaking, decision-making and meaning-making.

Findings

The COVID-19 pandemic was characterized by uncertainty and a need for continuous learning among the managers at the case hospitals. The learning process that arose was circular in nature, wherein trust played a crucial role in facilitating the flow of information and enabling the managers to get a good sense of the situation. This, in turn, allowed the managers to make decisions meaningful for the organization, which improved the trust for the managers. This circular process was iterated with higher frequency than usual and was a prerequisite for the managers’ learning. The practical implications are that a combined management with hierarchical and distributed management that uses the normal decision routes seems to be the most successful management method in a prolonged crisis as a pandemic.

Practical implications

The gained knowledge can benefit hospital organizations, be used in crisis education and to develop regional contingency plans for pandemics.

Originality/value

This study has explored learning during the COVID-19 pandemic and found a circular process, “the management learning wheel,” which supports management learning in prolonged crises.
Connect with care: informal knowledge protection practices to enhance knowledge sharing in networks of organizations
Authors: Thalmann Stefan , Maier Ronald , Remus Ulrich , Manhart Markus
Published: January 2024

Purpose

This paper aims to clarify how organizations manage their participation in networks to share and jointly create knowledge but also risk unwanted knowledge spillovers at the same time. As formal governance, trust and observation are less applicable in informal networks, the authors need to understand how members address the need to protect knowledge by informal practices. The study aims to investigate how the application of knowledge protection practices affects knowledge sharing in networks. The insights are relevant for organizational and network management to control knowledge risks but harvest the benefits of network engagement.

Design/methodology/approach

The authors opted for an exploratory study based on 60 semi-structured interviews with members of 10 networks. In two rounds, network managers, representatives and members of the networks were interviewed. The second round of interviews was used to validate the intermediate findings. The data were complemented by documentary analysis, including network descriptions.

Findings

Through analyzing and building on the theory of psychological contracts, two informal practices of knowledge protection were found in networks of organizations: exclude crucial topics and share on selected topics and exclude details and share a selected level of detail. The authors explored how these two practices are enacted in networks of organizations with psychological contracts.

Originality/value

Counter to intuition that the protection of knowledge can be strengthened only at the expense of knowledge sharing and vice versa, networks benefitted from more focused and increased knowledge sharing while reducing the risk of losing competitive knowledge by performing these knowledge protection practices.
Impact of emotional intelligence on knowledge hiding behaviour of teachers: a moderated mediation analysis
Authors: Shailja Shailja , Kumari Patiraj , Singla Himanshu
Published: January 2024

Purpose

Given the scarcity of research exploring the influence of emotional dimensions on knowledge hiding (KH), this paper aims to examine how various facets of emotional intelligence (EI) affect teachers’ tendencies to hide knowledge. Additionally, the study delves into the mediating influence of organizational cynicism (OC) and explores the moderating role of servant leadership (SL) in this context.

Design/methodology/approach

The non-probability sampling method was used to gather data from 542 university teachers teaching in India. Structural equation modelling using Smart-PLS has been used to test the hypothesis.

Findings

The study revealed that EI negatively influences KH. Additionally, OC mediates the relationship between EI and KH. Furthermore, SL moderates the relationship between OC and KH.

Originality/value

As per the authors’ knowledge, the present study makes an additional contribution by investigating the mediating role of OC in the relationship between EI and KH. Moreover, it also investigates the moderating role of SL in the relationship between OC and KH.
Contested ‘commune rurales’: Decentralisation and the (violent) struggle for public authority in the Democratic Republic of Congo
Authors: Büscher Karen , Perazzone Stephanie , Cuvelier Jeroen , Lumbu Stephane , Rwakira Espoir , Bulambo Paul , Mvano Yabauma Chrispin , Muzalia Godefroid
Published: January 2024

This article explores how decentralisation policy and specifically the establishment of communes rurales in DR Congo turned into a profoundly destabilising juncture, shaking existing governance arrangements. In particular, we examine how this has led to a reshuffle of power and a renegotiation of public authoritiy. By analysing the impact of decentralisation on the construction of and competition over public authority in three Congolese towns – Rubaya, Minembwe and Fungurume – we demonstrate how decentralisation is deeply politicised, with conflicting governance actors mobilising their power in an attempt to secure their claim to public authority. We argue that the establishment of communes rurales in eastern and southeastern DRC should be therefore understood as a strongly destabilising moment, changing the access of governance actors to resources and repertoires from which they build and legitimise their public authority. Depending on the specific context of the local political arena and its entanglements with larger struggles for power and control, this destabilising moment bears the potential for (violent) conflict. As such, we conclude that decentralisation has failed to live up to its promises of stability and peace while generating new sets of political fault lines and a re‐activation of (violent) conflict.