bluuebunny/crossref_metadata_2025 huggingface dataset:
Photoreceptor-induced LHL4 protects photosystem II inChlamydomonas reinhardtii
Authors: Dannay Marie , Bertin Chloé , Cavallari Eva , Albanese Pascal , Tolleter Dimitri , Giustini Cécile , Menneteau Mathilde , Brugière Sabine , Couté Yohann , Finazzi Giovanni , Demarsy Emilie , Ulm Roman , Allorent Guillaume
Published: February 2024

Photosynthesis, the fundamental process using light energy to convert CO2to organic matter, is vital for life on Earth. It relies on capturing light through light-harvesting complexes in evolutionarily well-conserved photosystems (PS) I and II and on the conversion of light energy into chemical energy. Composition and organization of both photosystem core complexes are well conserved across evolution. PSII is particularly sensitive to photodamage but benefits from a large diversity of photoprotective mechanisms, finely tuned for the specific light conditions. Light Harvesting Complex protein family members (LHC and LHC-like families) have acquired a dual function during evolution. Members of the LHC antenna complexes of photosystems capture light energy whereas others dissipate excess energy that cannot be harnessed for photosynthesis. This process mainly occurs through non photochemical quenching (NPQ). In this work, we focus on the LHL4 protein, which is a LHC-like protein induced by UV-B and blue light photoreceptor signaling pathways in the model green microalgaeChlamydomonas reinhardtii. We demonstrate that alongside established NPQ effectors, LHL4 plays a key role in photoprotection, preventing singlet oxygen accumulation in PSII and promoting cell survival upon light stress. LHL4 protective function is distinct from that of NPQ-related proteins, as it specifically and uniquely binds to the transient monomeric form of the core PSII complex, safeguarding its integrity. LHL4 characterization expands our understanding of the interplay between light harvesting and photoprotection mechanisms upon light stress in photosynthetic microalgae.
Evaluation of Bayesian Linear Regression Models for Gene Set Prioritization in Complex Diseases
Authors: Gholipourshahraki Tahereh , Bai Zhonghao , Shrestha Merina , Hjelholt Astrid , Kjølby Mads , Rohde Palle Duun , Sørensen Peter
Published: February 2024

Genome-wide association studies (GWAS) provide valuable insights into the genetic architecture of complex traits, yet interpreting their results remains challenging due to the polygenic nature of most traits. Gene set analysis offers a solution by aggregating genetic variants into biologically relevant pathways, enhancing the detection of coordinated effects across multiple genes. In this study, we present and evaluate a gene set prioritization approach utilizing Bayesian Linear Regression (BLR) models to uncover shared genetic components among different phenotypes and facilitate biological interpretation. Through extensive simulations and analyses of real traits, we demonstrate the efficacy of the BLR model in prioritizing pathways for complex traits. Simulation studies reveal insights into the model’s performance under various scenarios, highlighting the impact of factors such as the number of causal genes, proportions of causal variants, heritability, and disease prevalence. Application of both single-trait and multi-trait BLR models to real data, specifically GWAS summary data for type 2 diabetes (T2D) and related phenotypes, identifies significant associations with T2D-related pathways. Furthermore, comparison between single- and multi-trait BLR analyses highlights the superior performance of the multi-trait approach in identifying associated pathways, showcasing increased statistical power when analyzing multiple traits jointly. Additionally, enrichment analysis with integrated data from various public resources supports our results, confirming significant enrichment of diabetes-related genes within the top T2D pathways resulting from the multi-trait analysis. The BLR model’s ability to handle diverse genomic features, perform regularization, conduct variable selection, and integrate information from multiple traits, genders, and ancestries demonstrates its utility in understanding the genetic architecture of complex traits. Our study provides insights into the potential of the BLR model to prioritize gene sets, offering a flexible framework applicable to various datasets. This model presents opportunities for advancing personalized medicine by exploring the genetic underpinnings of multifactorial traits, potentially leading to tailored therapeutic interventions.
Mitochondrial origins of the pressure to sleep
Authors: Sarnataro Raffaele , Velasco Cecilia D. , Monaco Nicholas , Kempf Anissa , Miesenböck Gero
Published: February 2024

The neural control of sleep requires that sleep need is sensed during waking and discharged during sleep. To obtain a comprehensive, unbiased view of molecular changes in the brain that may underpin these processes, we have characterized the transcriptomes of single cells isolated from rested and sleep-deprived flies. Transcripts upregulated after sleep deprivation, in sleep-control neurons projecting to the dorsal fan-shaped body (dFBNs) but not ubiquitously in the brain, encode almost exclusively proteins with roles in mitochondrial respiration and ATP synthesis. These gene expression changes are accompanied by mitochondrial fragmentation, enhanced mitophagy, and an increase in the number of contacts between mitochondria and the endoplasmic reticulum, creating conduits for the replenishment of peroxidized lipids. The morphological changes are reversible after recovery sleep and blunted by the installation of an electron overflow in the respiratory chain. Inducing or preventing mitochondrial fission or fusion in dFBNs alters sleep and the electrical properties of sleep-control cells in opposite directions: hyperfused mitochondria increase, whereas fragmented mitochondria decrease, neuronal excitability and sleep. ATP levels in dFBNs rise after enforced waking because of diminished ATP consumption during the arousal-mediated inhibition of these neurons, which predisposes them to heightened oxidative stress. Consistent with this view, uncoupling electron flux from ATP synthesis relieves the pressure to sleep, while exacerbating mismatches between electron supply and ATP demand (by powering ATP synthesis with a light-driven proton pump) promotes sleep. Sleep, like ageing, may be an inescapable consequence of aerobic metabolism.
Is myeloid-derived growth factor a ligand of the sphingosine-1-phosphate receptor 2?
Authors: Zheng Yong-Shan , Liu Ya-Li , Xu Zeng-Guang , He Cheng , Guo Zhan-Yun
Published: February 2024

Secretory myeloid-derived growth factor (MYDGF) exerts beneficial effects on organ repair, probably via a plasma membrane receptor; however, the identity of the expected receptor has remained elusive. In a recent study, MYDGF was reported as an agonist of the sphingosine-1-phosphate receptor 2 (S1PR2), an A-class G protein-coupled receptor that mediates the functions of the signaling lipid, sphingosine-1-phosphate (S1P). In the present study, we conducted living cell-based functional assays to test whether S1PR2 is a receptor for MYDGF. In the NanoLuc Binary Technology (NanoBiT)-based β-arrestin recruitment assay and the cAMP-response element (CRE)-controlled NanoLuc reporter assay, S1P could efficiently activate human S1PR2 overexpressed in human embryonic kidney (HEK) 293T cells; however, recombinant human MYDGF, overexpressed either fromEscherichia colior HEK293 cells, had no detectable effect. Thus, the results demonstrated that human MYDGF is not a ligand of human S1PR2. Considering the high conservation of MYDGF and S1PR2 in evolution, MYDGF is also probably not a ligand of S1PR2 in other vertebrates.
Genetic evolution analysis of hemagglutinin and neuraminidase genes of H9N2 avian influenza virus in external environment of some areas of Yunnan Province, China from 2020 to 2023
Authors: Liu Zhaosheng , Fu Xiaoqing , Chen Yaoyao , Sun Yanhong , Zhang Meiling , Han Xiaoyu , Zhao Xiaonan , Zhou Jienan
Published: February 2024

Objective

To understand the molecular characteristics and genetic variation of hemagglutinin (HA) and neuraminidase (NA) genes of H9N2 subtype avian influenza virus (AIV) in the external environment of Yunnan Province, and to provide evidence for the prevention and control of H9N2 subtype AIV in this area.

Results

The HA and NA genes of 20 isolates belonged to Y280-like sub-branch. The nucleotide and amino acid homology of HA gene were 88.46%-99.81% and 89.08% -99.61%, respectively. The nucleotide and amino acid homology of NA gene were 88.85%-100% and 90.09%-100%, respectively. The HA protein cleavage site of 20 isolates was PSRSSRGLF, which was consistent with the molecular characteristics of low pathogenic avian influenza virus. The 226 th and 228 th positions of the receptor binding site are all L and G, which have the ability to bind to the mammalian sialic acid α-2,6 sialic acid receptor; HA protein had 7-8 glycosylation sites, and the main variation was the deletion of one site at 218 and the addition of one glycosylation site at 313 and 491. The main antigenic sites were G90E, S/T145D, D/N153G, A/S/F168N/E, T200R, N/D201G/T mutations. The NA protein neck of 20 isolates lacked 3 amino acids (TEI), which had the molecular characteristics of highly pathogenic avian influenza. NA protein had 6-8 glycosylation sites. The main variation was that two isolates increased a new glycosylation site NPTQ at the 2nd position, and one isolate increased a new glycosylation site NTTI at the 67th position. All isolates lost one site at the 402nd position, and some isolates lost at the 83rd and 365th positions. The amino acids at the active site and key site of NA protease were not mutated, and the isolates did not produce resistance to neuraminidase inhibitors.

Conclusion

The HA and NA genes of H9N2 subtype avian influenza virus in Yunnan Province have evolved continuously, but they still belong to the Y280 branch of the Eurasian lineage. Mutations in key sites may cause increased infectivity and transmission. The monitoring of H9N2 subtype avian influenza virus should be strengthened to prevent it from breaking the interspecies barrier and spreading to humans and lower mammals, so as to prevent the outbreak of H9N2 subtype avian influenza.
Mesencephalic projections to the nucleus accumbens shell modulate value updating during probabilistic reversal learning
Authors: Zühlsdorff Katharina , Piller Sammy , Sala-Bayo Júlia , Zhukovsky Peter , Lamla Thorsten , Nissen Wiebke , von Heimendahl Moritz , Deiana Serena , Nicholson Janet R. , Robbins Trevor W. , Alsiö Johan , Dalley Jeffrey W.
Published: February 2024

Cognitive flexibility, the capacity to adapt behaviour to changes in the environment, is impaired in a range of brain disorders, including substance use disorder and Parkinson’s disease. Putative neural substrates of cognitive flexibility include mesencephalic pathways to the ventral striatum (VS) and dorsomedial striatum (DMS), hypothesised to encode learning signals needed to maximize rewarded outcomes during decision-making. However, it is unclear whether mesencephalic projections to the ventral and dorsal striatum are distinct in their contribution to flexible reward-related learning. Here, rats acquired a two-choice spatial probabilistic reversal learning (PRL) task, reinforced on an 80%:20% basis, that assessed the flexibility of behaviour to repeated reversals of response-outcome contingencies. We report that optogenetic stimulation of projections from the ventral tegmental area (VTA) to the nucleus accumbens shell (NAcbS) in the VS significantly impaired reversal learning when optical stimulation was temporally aligned with negative feedback (i.e., reward omission). Moreover, the exploitation-exploration parameter,β, was increased (indicating greater exploitation of information) when this pathway was optogenetically stimulated after a spurious loss (i.e. an incorrect (20%) response at the 80% reinforrced location) compared to after a spurious win (i.e. a correct (20%) response at the 20% reinforced location). VTA → NAcbS stimulation during other phases of the behavioural task was without effect. Optogenetic stimulation of projection neurons from the substantia nigra (SN) to the DMS, aligned either with reward receipt or omission or prior to making a choice, had no effect on reversal learning. These findings are consistent with the notion that enhanced activity in VTA → NAcbS projections leads to maladaptive perseveration as a consequence of an inappropriate bias to exploitationviapositive reinforcement.
Efficient 3ʹ-end tailing of RNA with modified adenosine for nanopore direct total RNA sequencing
Authors: Yuan Yinan , Arneson Reed , Burke Emma , Apostle Alexander
Published: February 2024

Direct sequencing of total cellular RNA enables a better understanding of a broad spectrum of RNA species controlling cellular processes and organismal function. Current nanopore direct RNA sequencing method, however, only captures polyadenylated RNA for sequencing. To address this issue, we developed a unique 3’-end RNA tailing method to capture total RNA for nanopore direct RNA sequencing. Due to the distinct electrical signature of the added tail on nanopore, this method allows simultaneous detection of both non-polyadenylated and polyadenylated RNAs. We demonstrated the effectiveness of this method in capturing the dynamics of transcription and polyadenylation of chloroplast RNAs in plant cell. With its high efficiency in retaining total RNA on nanopore, this method has the potential to be broadly applied to RNA metabolism and functional genomics studies.
Developmentally stable representations of naturalistic image structure in macaque visual cortex
Authors: Lee Gerick M. , Rodríguez-Deliz C. L. , Bushnell Brittany N. , Majaj Najib J. , Movshon J. Anthony , Kiorpes Lynne
Published: February 2024

We studied visual development in macaque monkeys using texture stimuli, matched in local spectral content but varying in “naturalistic” structure. In adult monkeys, naturalistic textures preferentially drive neurons in areas V2 and V4, but not V1. We paired behavioral measurements of naturalness sensitivity with separately-obtained neuronal population recordings from neurons in areas V1, V2, V4, and inferotemporal cortex (IT). We made behavioral measurements from 16 weeks of age and physiological measurements as early as 20 weeks, and continued through 56 weeks. Behavioral sensitivity reached half of maximum at roughly 25 weeks of age. Neural sensitivities remained stable from the earliest ages tested. As in adults, neural sensitivity to naturalistic structure increased from V1 to V2 to V4. While sensitivities in V2 and IT were similar, the dimensionality of the IT representation was more similar to V4’s than to V2’s.
Simultaneous circulation and coinfection of Dengue clades and serotypes in Southern Brazil
Authors: Bermann Thales , Baethgen Ludmila Fiorenzano , Gregianini Tatiana Schäffer , Godinho Fernanda , Barcellos Regina Bones , Ruivo Amanda Pellenz , Bauerman Milena , Selayaran Taina Machado , dos Santos Franciellen Machado , Schoerer Julio Augusto , Möllmann Érica Bortoli , Martiny Fernanda Letícia , Lagranha Valeska Lizzi , de Oliveira Luiz Felipe Valter , da Veiga Ana Gorini , Zolet Andreia Carina Turchetto , Wallau Gabriel Luz , Salvato Richard Steiner
Published: February 2024

Dengue is an arthropod-borne virus with worldwide urban transmission mediated by anthropophilic vectors of the genusAedes. Currently, there is a substantial genotype diversity that belongs to at least four known serotypes. Tropical regions, where several serotypes cocirculate in the population, are hyperendemic, driving multiple outbreaks with variable disease manifestations. Notably, the Dengue virus burden is increasing in subtropical and temperate regions of the globe due to climatic changes associated with new outbreaks in naive and previously unaffected human populations. The introduction and endemic transmission of different clades and serotypes in these regions is highly concerning due to the known and still unknown consequences of Dengue infection on populations with diverse genetic backgrounds. Here, we characterized the coinfection of different Dengue clades and serotypes in Rio Grande do Sul, Brazil’s southernmost and subtropical state, by combining serotype-specific RT-PCR and deep sequencing. We found five coinfected patients in four municipalities where these clades and serotypes circulated simultaneously. Our data suggests that coinfection events account for a minority of total cases, but these findings may reflect the early transmission phases of some Dengue clades. Hence, close monitoring is warranted to evaluate coinfection rates and associated clinical consequences as clade prevalence changes.
A comprehensive analysis of non-pharmaceutical interventions and vaccination on Ebolavirus disease outbreak: Stochastic modeling approach
Authors: Ko Youngsuk , Lee Jacob , Seo Yubin , Jung Eunok
Published: February 2024

Ebolavirus disease (EVD) outbreaks have intermittently occurred since the first documented case in the 1970s. Due to its transmission characteristics, large outbreaks have not been observed outside Africa. However, within the continent, significant outbreaks have been attributed to factors such as endemic diseases with similar symptoms and inadequate medical infrastructure, which complicate timely diagnosis. In this study, we employed a stochastic modeling approach to analyze the spread of EVD during the early stages of an outbreak, with an emphasis on inherent risks. We developed a model that considers medical staff and unreported cases, and assessed the effect of non-pharmaceutical interventions (NPIs) using actual data. Our results indicate that the implementation of NPIs led to a decrease in the transmission rate and infectious period by 30% and 40% respectively, following the declaration of the outbreak. We also investigated the risks associated with delayed outbreak recognition. Our simulations suggest that, when accounting for NPIs and recognition delays, prompt detection could have resulted in a similar outbreak scale, with approximately 50% of the baseline NPIs effect. Finally, we discussed the potential effects of a vaccination strategy as a follow-up measure after the outbreak declaration. Our findings suggest that a vaccination strategy can reduce both the burden of NPIs and the scale of the outbreak.

Author summary

Our research employs a stochastic model to analyze the early-stage spread of Ebolavirus Disease. We incorporated factors such as medical staffs and unreported cases, and utilized real data to evaluate the impact of non-pharmaceutical interventions on disease transmission. Our findings indicate that rapid outbreak recognition could effectively control disease spread with reduced efforts. Furthermore, we explored the potential implementation of a vaccination strategy following an outbreak declaration. Our results suggest that such a strategy could mitigate both the scale of the outbreak and the necessity for additional interventions.
Diverse Relationships Between Antibiotic Resistance and Host Age: A Meta-Analysis Across Antibiotic Classes and Bacterial Genera
Authors: Binsted Lucy E. , McNally Luke
Published: February 2024

Antimicrobial resistance (AMR) poses an urgent public health challenge. To improve patient outcomes and design interventions we must identify patient characteristics which predict the presence of AMR pathogens. One potential and commonly collected patient characteristic is host age, consensus remains elusive regarding its impact on the probability of infecting pathogens being resistant to antimicrobials. Here, we employ a meta-analysis to consolidate and compare these previous studies and examine the relationship between antibiotic resistance and host age across bacteria and antibiotics. We show that although the probability that infecting bacteria are antimicrobial resistant increases with host age on average, diverse patterns exist across antibiotic classes and bacterial genera, including negative, humped, and U-shaped relationships. We further illustrate, using a compartmental epidemiological model, that this variation is likely driven by differences in antibiotic consumption or incidence of bacterial infection/carriage between age groups, combined with age assortative transmission. These findings imply that empirical antibiotic therapy could be improved by considering age-specific local resistance levels (compared with overall local resistance levels), resulting in improved treatment success and reduced spread of antibiotic resistance. They additionally display consequences of assuming population homogeneity in epidemiological models. Finally, they indicate that the landscape of the already severe resistance crisis is likely to change as the age distribution of the human population shifts.
Attentional inhibition by alpha power is modulated by faster theta rhythm and audio-visual congruency during natural speech perception
Authors: Byczynski Gabriel , Park Hyojin
Published: February 2024

Audio-visual processing is an essential aspect of human communication, however the mechanisms that underlie attention and processing in the auditory and visual domains are still limited. In order to understand how the brain attends to and processes information while ignoring irrelevant information, we employed a complex audio-visual paradigm to understand how the brain monitors and integrates audio-visual information in congruent and incongruent conditions. In three conditions, participants watched a Ted Talk presentation while listening to 1) congruent audio in both ears, 2) congruent audio in one ear and incongruent in the other (attending to congruent) or 3) congruent audio in one ear and incongruent audio in the other (attending to the incongruent). In order to investigate correlates of attention and audio-visual processing, we developed a novel method of detecting audio-visual congruency in the fluctuation rhythms of alpha power during each condition. Employing this method, we found that higher frequency alpha power fluctuation, falling in the delta-theta range, corresponded regionally to the side of attention, suggesting a novel mechanism of processing in that alpha-band activity may act as a temporal filter or attentional mechanism during audio-visual attention.
Sand flies and Toscana virus: intra-vector infection dynamics and impact onPhlebotomus perniciosuslife-history traits
Authors: Laroche Lison , Bañuls Anne-Laure , Charrel Rémi , Fontaine Albin , Ayhan Nazli , Prudhomme Jorian
Published: February 2024

Toscana virus (TOSV) is a leading cause of summer viral meningitis in central Italy and south of France, and can cause severe neurological cases. Within the Mediterranean basin, it is transmitted by hematophagous sand flies belonging to thePhlebotomusgenus. Despite the identification of the primary TOSV vectors, the virus’s developmental cycle in vector species remains largely unknown. Limited research has been conducted on transmission dynamics and the vectorial competence and capacity of the principal TOSV vector,Phlebotomus perniciosus. In this context, we investigated the intra-vector TOSV infection dynamics inPh. perniciosus, as well as its impact on the vector’s life history traits. Female sand flies were experimentally infected with TOSV though an artificial blood meal. Systemic dissemination of the virus was observed approximately three days post-infection, potentially resulting in a shorter extrinsic incubation period. Moreover, the study revealed a longer hatching time for eggs laid by infected females. This research not only confirmed the vector competence ofPh. perniciosusbut also provided the first insight into TOSV’s developmental cycle and its impact on the vector. These findings prompt further exploration of TOSV transmission dynamics, raise new hypotheses on the virus transmission and highlight the importance of follow-up studies.

Author summary

Toscana virus (TOSV) is a reemerging sandfly-borne virus causing neuroinvasive infections in humans. This virus is endemic in the Mediterranean basin, with a potential risk of introduction in northern Europe and Asia. Despite decades of research, few studies have focused on the development cycle of TOSV in sand flies and the dynamics of transmission. Here, we provide a comprehensive study of the intra-vector dynamics of TOSV infection and its impact on both vector biology and transmission. Through experimental infections of the major vectorPhlebotomus perniciosus, we not only confirmed vector competence but also provided the first insight into the TOSV developmental cycle in the vector by estimating the extrinsic incubation period at six days. Our study reveals an impact of TOSV infection on vector hatching time leading to a delayed emergence of infected sand flies, with a potential impact on transmission. Our findings encourage further exploration of transmission dynamics, raise new hypotheses on alternative transmission pathways, and emphasize the importance of follow-up studies.
The energy metabolism ofCupriavidus necatorin different trophic conditions
Authors: Jahn Michael , Crang Nick , Gynnå Arvid H. , Kabova Deria , Frielingsdorf Stefan , Lenz Oliver , Charpentier Emmanuelle , Hudson Elton P.
Published: February 2024

The ‘knallgas’ bacteriumCupriavidus necatoris attracting interest for biotechnological applications due to its extremely versatile metabolism.C. necatorcan use hydrogen or formic acid as an energy source, fixes CO2viathe Calvin-Benson-Bassham (CBB) cycle, and also grows well on various other organic acids and sugars. Its tri-partite genome is notable for its size and manifold duplications of key genes (CBB cycle, hydrogenases, nitrate reductases). Comparatively little is known about which of these (iso-) enzymes and their cofactors are actually utilized for growth on different energy sources.

Here, we investigated the energy metabolism ofC. necatorH16 by growing a barcoded transposon knockout library on various substrates including succinate, fructose, hydrogen (H2/CO2) and formic acid. The fitness contribution of each gene was determined from enrichment or depletion of the corresponding mutants. Fitness analysis revealed that 1) some, but not all, molybdenum cofactor biosynthesis genes were essential for growth on formate and nitrate respiration. 2) Soluble formate dehydrogenase (FDH) was the dominant enzyme for formate oxidation, not membrane-bound FDH. 3) For hydrogenases, both soluble and membrane-bound enzymes were beneficial for lithoautotrophic growth. 4) Of the six terminal respiratory complexes inC. necatorH16, only some are utilized and utilization depends on the energy source. 5) Deletion of hydrogenase-related genes boosted heterotrophic growth, and we show that the relief from associated protein cost is responsible for this phenomenon.

This study evaluates the contribution of each ofC. necator’s genes to fitness in biotechnologically relevant growth regimes. Our results illustrate the genomic redundancy of this generalist bacterium, and may inspire future strategies for strain engineering.

Graphical Abstract

Highlights

a barcoded transposon library was used to assess gene fitness for hydrogenase, formate dehydrogenase and electron transport chain complexes

the utilization of terminal respiratory complexes is substrate specific

soluble formate dehydrogenase is more important than the membrane-bound enzyme

soluble hydrogenase and membrane-bound hydrogenase are equally utilized

inactivation of hydrogenase and its accessory genes leads to faster heterotrophic growth

we demonstrate that faster growth is caused by the relief of protein synthesis burden

fitness data is available in an interactive app athttps://m-jahn.shinyapps.io/ShinyLib/
rf and thermal design studies of a 704.4 MHz,
β≈0.2
, continuous-wave rf quadrupole accelerator for frequency jump
Authors: Zhou Bowen , Zhang Chuan
Published: February 2024

The radio-frequency quadrupole (RFQ) linac is often used as the first radio-frequency (rf) structure for both bunching and preaccelerating proton or heavy ion beams directly behind an ion source or a low-energy beam transport section. Typically, RFQ linacs operate at frequencies below 450 MHz and beam velocity ranges from β=0.01–0.08. Taking the MYRRHA project as an example, a 704.4 MHz continuous-wave (cw) RFQ linac has been recently proposed to realize an efficient fourfold frequency jump at β≈0.2. Due to its high frequency, small dimensions, and cw operation mode, careful design studies for the RFQ cavity structure including the water-cooling channels have been further performed, integrating the idea of using additive manufacturing technology for future construction. Systematic rf and thermal simulations and analysis demonstrated the reliability of the 704.4 MHz RFQ linac at cw operation and the frequency tuning ability via water-speed adjustments. This investigation shows that it could be a highly promising solution to perform an efficient frequency jump with a high-frequency RFQ accelerator at β≈0.2 for large-scale hadron linacs, which could potentially shorten the low- and medium-β parts of the whole facility.

Published by the American Physical Society
2024
Towards a high-intensity muon source
Authors: Cai Han-Jie , He Yuan , Liu Shuhui , Jia Huan , Qin Yuanshuai , Wang Zhijun , Wang Fengfeng , Zhao Lixia , Pu Neng , Niu Jianwei , Chen Liangwen , Sun Zhiyu , Zhao Hongwei , Zhan Wenlong
Published: February 2024

A high-intensity muon source driven by a continuous-wave superconducting linac holds the potential to significantly advance the intensity frontier of muon sources. Alongside advancements in accelerator technologies, breakthroughs in muon production target and collection schemes are essential. After a brief introduction to the development of the accelerator-driven system superconducting linac, a novel muon production target is proposed, utilizing a free-surface liquid lithium jet capable of handling the heat power generated by a proton beam with an energy of 600 MeV and a current of 5 mA. It is predicted by our simulation studies that the lithium target is more efficient in surface muon production compared to the rotating graphite target. The parameter space of the front end consisting of a lithium target and a large-aperture capture solenoid is explored, from the perspective of production efficiency, capture efficiency, and characteristics of the surface muon beam.

Published by the American Physical Society
2024
First simultaneous global QCD analysis of dihadron fragmentation functions and transversity parton distribution functions
Authors: Cocuzza C. , Metz A. , Pitonyak D. , Prokudin A. , Sato N. , Seidl R. ,   Jefferson Lab Angular Momentum (JAM) Collaboration
Published: February 2024

We perform a comprehensive study within quantum chromodynamics (QCD) of dihadron observables in electron-positron annihilation, semi-inclusive deep-inelastic scattering, and proton-proton collisions, including recent cross section data from Belle and azimuthal asymmetries from STAR. We extract simultaneously for the first time π+π− dihadron fragmentation functions (DiFFs) and the nucleon transversity distributions for up and down quarks as well as antiquarks. For the transversity distributions we impose their small-x asymptotic behavior and the Soffer bound. In addition, we utilize a new definition of DiFFs that has a number density interpretation to then calculate expectation values for the dihadron invariant mass and momentum fraction. Furthermore, we investigate the compatibility of our transversity results with those from single-hadron fragmentation (from a transverse momentum dependent/collinear twist-3 framework) and the nucleon tensor charges computed in lattice QCD. We find a universal nature to all of this available information. Future measurements of dihadron production can significantly further this research, especially, as we show, those that are sensitive to the region of large parton momentum fractions.

Published by the American Physical Society
2024
Sublattice scars and beyond in two-dimensional
U(1)
quantum link lattice gauge theories
Authors: Sau Indrajit , Stornati Paolo , Banerjee Debasish , Sen Arnab
Published: February 2024

In this article, we elucidate the structure and properties of a class of anomalous high-energy states of matter-free U(1) quantum link gauge theory Hamiltonians using numerical and analytical methods. Such anomalous states, known as quantum many-body scars in the literature, have generated a lot of interest due to their athermal nature. Our starting Hamiltonian is H=Okin+λOpot, where λ is a real-valued coupling, and Okin (Opot) are summed local off-diagonal (diagonal) operators in the electric flux basis acting on the elementary plaquette □. The spectrum of the model in its spin-12 representation on Lx×Ly lattices reveal the existence of sublattice scars, |ψs⟩, which satisfy Opot,□|ψs⟩=|ψs⟩ for all elementary plaquettes on one sublattice and Opot,□|ψs⟩=0 on the other, while being simultaneous zero modes or nonzero integer-valued eigenstates of Okin. We demonstrate a “triangle relation” connecting the sublattice scars with nonzero integer eigenvalues of Okin to particular sublattice scars with Okin=0 eigenvalues. A fraction of the sublattice scars have a simple description in terms of emergent short singlets, on which we place analytic bounds. We further construct a long-ranged parent Hamiltonian for which all sublattice scars in the null space of Okin become unique ground states and elucidate some of the properties of its spectrum. In particular, zero energy states of this parent Hamiltonian turn out to be exact scars of another U(1) quantum link model with a staggered short-ranged diagonal term.

Published by the American Physical Society
2024
Top Yukawa coupling determination at high energy muon collider
Authors: Liu Zhen , Lyu Kun-Feng , Mahbub Ishmam , Wang Lian-Tao
Published: February 2024

The Top Yukawa coupling profoundly influences several core mysteries linked to the electroweak scale and the Higgs boson. We study the feasibility of measuring the Top Yukawa coupling at high energy muon colliders by examining the high energy dynamics of the weak boson fusion to top quark pair processes. A deviation of the Top Yukawa coupling from the Standard Model would lead to a modified VV→tt¯ process, violating unitarity at high energy. Our analysis reveals that utilizing a muon collider with a center-of-mass energy of 10 TeV and an integrated luminosity of 10  ab−1 allows us to investigate the Top Yukawa coupling with a precision surpassing 1.5%, more than one order of magnitude better than the precision from tt¯h channel at muon colliders. This precision represents a notable enhancement compared to the anticipated sensitivities of the High-Luminosity LHC (3.4%) and those at muon colliders derived from the tt¯H process.

Published by the American Physical Society
2024
Holographic odderon at TOTEM?
Authors: Hechenberger Florian , Mamo Kiminad A. , Zahed Ismail
Published: February 2024

We consider the contribution of the Odderon to diffractive pp and pp¯ elastic scattering at large center of mass energy. We identify the Odderon and Pomeron with the Reggeized 1±− and 2++ glueballs in the bulk, respectively. We use for the gravity dual description the repulsive wall model, to account for the proper Gribov diffusion for off-forward scattering. The eikonalized and unitarized amplitudes exhibit a vanishingly small rho-parameter, and a slope parameter fixed by twice the closed string slope. The results for the differential and total cross sections are compared to the empirical results reported recently by the TOTEM collaboration.

Published by the American Physical Society
2024
Strain-engineered magnon states in two-dimensional ferromagnetic monolayers
Authors: Wei Bin , Zhu Jia-Ji , Song Yun , Chang Kai
Published: February 2024

We systematically investigate the strain-engineered magnon states in two-dimensional (2D) ferromagnetic monolayers. By suitable engineering of an inhomogeneous strain, we demonstrate the emergence of magnon Landau levels and magnon snake states in 2D ferromagnetic monolayers. We show a magnon valley Hall effect and valley filter without relying on any external fields. Our proposal offers us another way to manipulate magnon valley transport and construct different types of flexible spintronic devices, and is experimentally feasible for 2D ferromagnetic materials by using state-of-art techniques.

Published by the American Physical Society
2024
Estimating many properties of a quantum state via quantum reservoir processing
Authors: Li Yinfei , Ghosh Sanjib , Shang Jiangwei , Xiong Qihua , Zhang Xiangdong
Published: February 2024

Estimating properties of a quantum state is an indispensable task in various applications of quantum information processing. To predict properties in the postprocessing stage, it is inherent to first perceive the quantum state with a measurement protocol and store the information acquired. In this paper, we propose a general framework for constructing classical approximations of arbitrary quantum states with quantum reservoirs. A key advantage of our method is that only a single local measurement setting is required for estimating arbitrary properties, while most of the previous methods need an exponentially increasing number of measurement settings. To estimate M properties simultaneously, the size of the classical approximation scales as lnM. Moreover, this estimation scheme is extendable to higher-dimensional systems and hybrid systems with nonidentical local dimensions, which makes it exceptionally generic. We support our theoretical findings with extensive numerical simulations.

Published by the American Physical Society
2024
Board structure and risk-taking behavior: evidence from the financial sector of Pakistan
Authors: Javed Maryam , Mehmood Kashif , Ghafoor Abdul , Parveen Asma
Published: February 2024

Purpose

The board structure (BS) is pivotal in modern corporate governance (CG). This study aims to investigate BS variables (BSIZE, BIND and chief executive officer [CEO] duality) and their correlation with risk-taking behavior indicators, enriching the understanding of how CG shapes financial institutions’ (FIs) decision-making in Pakistan.

Design/methodology/approach

By scrutinizing data from 67 financial entities listed on the Stock Exchange of Pakistan spanning from 2011 to 2022 through panel data regression techniques, the research emphasizes that BS holds a substantial influence over the risk tendencies exhibited by these firms.

Findings

Key findings suggest that board size has a positive influence, aligned with previous CG research. Smaller boards perform better and avoid excessive risk-taking, contrasting some negative relationship claims. More independent directors are recommended to curtail risk and financial disruption. Holding both CEO and chair roles reduces risk exposure, resonating with reputational and employment risk theory. It is essential to recognize that BS’s impact on risk-taking is nuanced and context-dependent.

Practical implications

Policymakers, scholars, practitioners and investors working in the market for financial companies might greatly benefit from the empirical findings of this study. Imposing mandates on FIs to uphold adequate capital reserves functions as a safeguard against unforeseen losses, thereby diminishing the probability of unwarranted risk-taking.

Originality/value

Prior studies in this domain predominantly focus on nonfinancial sectors. In addition, existing research often explores the relationship between BS and firm risk-taking solely within the banking sector, overlooking other FIs. This study contributes by using a comprehensive data set encompassing all types of FIs, thus extending the existing literature.
A review of the current state and future trends in modern methods of construction research
Authors: Doan Dat Tien , Mai Tuyet Phuoc Anh , GhaffarianHoseini Ali , Ghaffarianhoseini Amirhosein , Naismith Nicola
Published: February 2024

Purpose

This study aims to identify the primary research areas of modern methods of construction (MMC) along with its current trends and developments.

Design/methodology/approach

A combination of bibliometric and qualitative analysis is adopted to examine 1,957 MMC articles in the Scopus database. With the support of CiteSpace 6.1.R6, the clusters, leading authors, journals, institutions and countries in the field of MMC are examined.

Findings

Offsite construction, inter-modular connections, augmenting output, prefabricated concrete beams and earthquake-resilient prefabricated beam–column steel joints are the top five research areas in MMC. Among them, offsite construction and inter-modular connections are significantly focused, with many research articles. The potential for collaboration, among prominent authors such as Wang, J., Liu, Y. and Wang, Y., explains the recent rapid growth of the MMC field of research. With a total of 225 articles, Engineering Structures is the journal that has published the most articles on MMC. China is the leading country in this field, and the Ministry of Education China is the top institution in MMC.

Originality/value

The findings of this study bear significant implications for stakeholders in academia and industry alike. In academia, these insights allow researchers to identify research gaps and foster collaboration, steering efforts toward innovative and impactful outcomes. For industries using MMC practices, the clarity provided on MMC techniques facilitates the efficient adoption of best practices, thereby promoting collaboration, innovation and global problem-solving within the construction field.
Industry 4.0: how digital transformation affects stock prices of Chinese and American companies
Authors: Fedorova Elena , Aleshina Daria , Demin Igor
Published: February 2024

Purpose

The goal of this work is to evaluate how digital transformation disclosure in corporate news and press releases affects stock prices. We examine American and Chinese companies from the energy and industry sectors for two periods: pre-COVID-19 and during the COVID-19 pandemic.

Design/methodology/approach

To estimate the effects of disclosure of information related to digital transformation, we applied the bag-of-words (BOW) method. As the benchmark dictionary, we used Kindermann et al. (2021), with the addition of original dictionaries created via Latent Dirichlet allocation (LDA) analysis. We also employed panel regression analysis and random forest.

Findings

For USA energy sector, all aspects of digital transformation were insignificant in pre-COVID-19 period, while sustainability topics became significant during the pandemic. As for the Chinese energy sector, digital strategy implementation was significant in pre-pandemic period, while digital technologies adoption and business model innovation became relevant in COVID-19 period. The results show the greater significance of digital transformation aspects for industrials sectors compared to the energy sector. The result of random forest analysis proves the efficiency of the authors’ dictionary which could be applied in practice. The developed methodology can be considered relevant.

Originality/value

The research contributes to the existing literature in theoretical, empirical and methodological ways. It applies signaling and information asymmetry theories to the financial markets, digital transformation being used as an instrument. The methodological contribution of this article can be described in several ways. Firstly, our data collection process differs from that in previous papers, as the data are gathered “from investor’s point of view”, i.e. we use all public information published by the company. Secondly, in addition to the use of existing dictionaries based on Kindermann et al. (2021), with our own modifications, we apply the original methodology based on LDA analysis. The empirical contribution of this research is the following. Unlike past works, we do not focus on particular technologies (Hong et al., 2023) connected with digital transformation, but try to cover all multi-dimensional aspects of the transformational process and aim to discover the most significant one.
Police misconduct and social media: perceptions of aspiring future police officers
Authors: Turner James , Rogers Colin , Pepper Ian
Published: February 2024

Purpose

The research aimed to explore the perceptions of aspiring future police officers studying at a university in relation to the actions to be taken with regards to typical posts on social media by a fictitious off and on-duty police officer. This in turn would inform future police workforce requirements.

Design/methodology/approach

Policing students who expressed their aspirations as future police officers were recruited. A total of 99 students studying the College of Policing licensed Professional Policing Degree at the University of South Wales, took part in Hydra Immersive Simulations to ascertain their perception of social media posts by a fictitious serving police officer. The students were asked to rate the appropriateness of the social media posts as groups, and as individuals.

Findings

The findings suggest that, whilst the majority of students identified misconduct issues in the social media posts, the response to how the fictitious police officer should be dealt with varied. In addition, it would appear that there may be a need for those involved in policing education to reinforce, in an ongoing basis, knowledge of the College of Policing Code of Ethics, misconduct rules, regulations and increase awareness of unacceptable social media posts.

Research limitations/implications

The research was conducted with professional policing degree (PPD) students from one university.

Practical implications

It is important to reinforce The College of Policing Code of Ethics, expected professional standards and an understanding of what constitutes unacceptable social media posts throughout the education of aspiring police officers. As this has the potential, if recruited, to impact on the service.

Originality/value

Limited research has been conducted in relation to the College of Policing licensed higher education programme, the PPD, equipping aspiring police officers to successfully join the service and influence the cultural change.