bluuebunny/crossref_metadata_2025 huggingface dataset:
Self-organized emergence of modularity, hierarchy, and mirror reversals from competitive synaptic growth in a developmental model of the visual pathway
Authors: Chandra Sarthak , Khona Mikail , Konkle Talia , Fiete Ila R.
Published: January 2024

A hallmark of the primate visual system is itsarchitectural organizationconsisting of multiple distinct (modular) areas that connect hierarchically. These areas exhibit specificspatial organizationon the cortical sheet, with primary visual cortex at the center and subsequent regions in the hierarchy encircling the earlier one, and detailedtopological organization, with retinotopy in each area but striking mirror reversals across area boundaries. The developmental rules that drive the simultaneous formation of these architectural, spatial, and topographic aspects of organization are unknown. Here we demonstrate that a simple synaptic growth rule driven by spontaneous activity and heterosynaptic competition generates a detailed connectome of the visual pathway, with emergence of all three types of organization. We identify a theoretical principle — local greedy wiring minimization via spontaneous drive (GWM-S) — implemented by the mechanism, and use this insight to propose biologically distinct growth rules that predict similar endpoints but testably distinguishable developmental trajectories. The same rules predict how input geometry and cortical geometry together drive emergence of hierarchical, convolution-like, spatially and topographically organized sensory processing pathways for different modalities and species, providing a possible explanation for the observed pluripotency of cortical structure formation. We find that the few parameters governing structure emergence in the growth rule constitute simple knobs for rich control, that could (potentially genetically) encode a projection neuron-like connectivity patterns and interneuron-like ones. In all, the presented rules provide a parsimonious mechanistic model for the organization of sensory cortical hierarchies even without detailed genetic cues for features like map reversal, and provide numerous predictions for experiment during normal and perturbed development.
Diverse bacteriohemerythrin genes ofMethylomonas denitrificansFJG1 provide insight into the survival and activity of proteobacterial methanotrophs under hypoxia
Authors: Weiblen Cerrise , Sauvageau Dominic , Stein Lisa Y.
Published: January 2024

Proteobacterial methanotrophic bacteria are dependent on the oxidation of methane and methanol for the assimilation of carbon. Interestingly, these types of methanotrophs can thrive in oxygen-depleted zones of lakes and other aquatic ecosystems despite the fact they are considered obligate aerobes. Bacteriohemerythrin (Bhr), a homologue of eukaryotic hemerythrin, is a protein associated with oxygen binding. The model gammaproteobacterial methanotrophic strain,Methylomonas denitrificansFJG1, oxidizes methane at the expense of nitrate reduction under extreme hypoxia and upregulatesbhrgenes, yet this strain encodes 10 homologues ofbhrin its genome. UsingM. denitrificansFJG1 as a model, this study examined the prevalence and phylogeny of each of its 10bhrhomologues in other methanotroph and general bacterial genomes. One gene copy denoted as “bhr-00” was found to be methanotroph-specific, was upregulated under hypoxia inM. denitrificansFJG1, and was predicted to have a structure nearly identical to the crystalized, oxygen-scavenging, Bhr-Bath protein from,Methylococcus capsulatusBath. Other upregulatedbhrgenes from hypoxic cultures of nitrate-grownM. denitrificansFJG1 included those with gene neighborhoods related to oxygen sensing, denitrification and chemotaxis. Together, this study uncovered multifunctional roles of bacteriohemerythrin proteins encoded and expressed by methanotrophs that likely enable their survival in hypoxic ecosystems.

Importance

Aerobic gammaproteobacterial methanotrophs encoding bacteriohemerythrin (bhr) genes are reported to have an enhanced ability to survive and grow in oxygen-limited environments. The methanotrophic bacterium,Methylomonas denitrificansFJG1, encodes 10 copies ofbhrgenes, of which 7 are expressed under oxygen depleted and denitrifying conditions. Comparing these 10bhrgene homologues fromM. denitrificansFJG1 with those from other prokaryotic genomes revealed that copy “bhr-00” is nearly exclusive to methanotrophs. Gene neighbourhoods surrounding conservedbhrgene sequences in methanotroph genomes suggest a range of potential functions including oxygen sensing and delivery, chemotaxis, and nitrate reduction. The results from this study illuminate a previously undescribed diversity of the structure and function ofbhrgenes inM. denitrificansFJG1 and related methanotrophic bacteria and pinpoints roles of Bhr that likely promote survival of methanotrophs in hypoxic ecosystems.
The concept of the gain curve
Authors: Burd Martin
Published: January 2024

Gain curves were introduced to explain how hermaphrodites could displace a dioecious population, and to account for sexual allocation in hermaphrodites. Terms for gamete production employed for the first purpose were transformed for the second into male and female gain curves that ostensibly defined fitness outcomes. These gain curves pose a conceptual challenge if they are specified separately because fitness at the population level cannot occur through one sex function independently of success through the other. If gain curves truly represent fitness outcomes, anomalies can arise, such as inequality of total male and female fitness in a population. Gain curves were originally used in a mathematical framework that treated the ostensible gain functions as inputs of male and female actors to a mating arena rather than as mating outcomes from that arena. I present a model of sex allocation that incorporates power functions to describe both gamete production and fitness gain in a manner that explicitly separates these two roles. In this formulation, the gamete production functions have the identical effect on optimal sex allocation originally attributed to gain curves while the true fitness gain curves lose nearly all effect on the optimum. Thus, despite the label, gain curves were implicitly describing inputs rather than outcomes. Because gain curves have been a staple of evolutionary ecology for decades, the implication is that much of our understanding of sexual allocation in hermaphrodites needs to be revisited. I outline some directions such an effort might take.
Self-reactive B cells traverse a perfect storm of somatic mutagenesis to cause a virus-induced autoimmune disease
Authors: Young Clara , Singh Mandeep , Jackson Katherine JL , Field Matt A , Peters Timothy J , Angioletti-Uberti Stefano , Frenkel Daan , Ravishankar Shyamsundar , Gupta Money , Wang Jing J , Agapiou David , Faulks Megan L , Al-Eryani Ghamdan , Luciani Fabio , Gordon Tom P , Reed Joanne H , Danta Mark , Carr Andrew , Kelleher Anthony D , Dore Gregory J , Matthews Gail , Brink Robert , Bull Rowena A , Suan Daniel , Goodnow Christopher C
Published: January 2024

The unexplained association between infection and autoimmune disease is strongest for hepatitis C virus-induced cryoglobulinemic vasculitis (HCV-CV). We traced the evolution of the pathogenic rheumatoid factor (RhF) autoantibodies in four HCV-CV patients by deep single cell multi-omic analysis, revealing three sources of B cell somatic mutation converged to drive accumulation of a large disease causing clone. A sensitive method for quantifying low affinity binding revealed three recurring heavy/light chain combinations created byV(D)Jrecombination bound self IgG but not viral E2 antigen. Whole genome sequencing revealed accumulation of thousands of somatic mutations, at levels comparable to CLL and normal memory B cells, but with 1-2 corresponding to driver mutations found recurrently in B cell leukemia/lymphoma.V(D)Jhypermutation created autoantibodies with compromised solubility. In this virus-induced autoimmune disease, infection promotes a perfect storm of somatic mutagenesis in the descendants of a single B cell.
Multiple DNA repair pathways prevent acetaldehyde-induced mutagenesis in yeast
Authors: Porcher Latarsha , Vijayraghavan Sriram , McCollum James , Mieczkowski Piotr A , Saini Natalie
Published: January 2024

Acetaldehyde is the primary metabolite of alcohol and is present in many environmental sources including tobacco smoke. Acetaldehyde is genotoxic, whereby it can form DNA adducts and lead to mutagenesis. Individuals with defects in acetaldehyde clearance pathways have increased susceptibility to alcohol-associated cancers. Moreover, a mutation signature specific to acetaldehyde exposure is widespread in alcohol and smoking-associated cancers. However, the pathways that repair acetaldehyde-induced DNA damage and thus prevent mutagenesis are vaguely understood. Here, we usedSaccharomyces cerevisiaeto systematically delete genes in each of the major DNA repair pathways to identify those that alter acetaldehyde-induced mutagenesis. We found that deletion of the nucleotide excision repair (NER) genes,RAD1orRAD14, led to an increase in mutagenesis upon acetaldehyde exposure. Acetaldehyde-induced mutations were dependent on translesion synthesis as well as DNA inter-strand crosslink (ICL) repair inΔrad1strains. Moreover, whole genome sequencing of the mutated isolates demonstrated an increase in C→A changes coupled with an enrichment of gCn→A changes in the acetaldehyde-treatedΔrad1isolates. The gCn→A mutation signature has been shown to be diagnostic of acetaldehyde exposure in yeast and in human cancers. We also demonstrated that the deletion of the two DNA-protein crosslink (DPC) repair proteases,WSS1andDDI1, also led to increased acetaldehyde-induced mutagenesis. Defects in base excision repair (BER) led to a mild increase in mutagenesis, while defects in mismatch repair (MMR), homologous recombination repair (HR) and post replicative repair pathways did not impact mutagenesis upon acetaldehyde exposure. Our results in yeast were further corroborated upon analysis of whole exome sequenced liver cancers, wherein, tumors with defects in ERCC1 and ERCC4 (NER), FANCD2 (ICL repair) or SPRTN (DPC repair) carried a higher gCn→A mutation load than tumors with no deleterious mutations in these genes. Our findings demonstrate that multiple DNA repair pathways protect against acetaldehyde-induced mutagenesis.
Investigation of Zur-regulated metal transport systems reveals an unexpected role of pyochelin in zinc homeostasis
Authors: Secli Valerio , Michetti Emma , Pacello Francesca , Iacovelli Federico , Falconi Mattia , Astolfi Maria Luisa , Visaggio Daniela , Visca Paolo , Ammendola Serena , Battistoni Andrea
Published: January 2024

Limiting the availability of transition metals at infection sites serves as a critical defense mechanism employed by the innate immune system to combat microbial infections.Pseudomonas aeruginosaexhibits a remarkable ability to thrive in zinc-deficient environments, which is facilitated by intricate cellular responses governed by numerous genes regulated by the zinc-responsive transcription factor Zur. Many of these genes have unknown functions, including those within the predictedPA2911-PA2914andPA4063-PA4066operons. A bioinformatic analysis revealed thatPA2911-PA2914comprises a TonB-dependent outer membrane receptor and an inner membrane ABC-permease responsible for importing metal-chelating molecules, whereasPA4063-PA4066contains genes encoding a MacB transporter, likely involved in the export of large molecules. Molecular genetics and biochemical experiments, feeding assays, and intracellular metal content measurements demonstrated thatPA2911-PA2914andPA4063-PA4066are engaged in the import and export of the pyochelin-cobalt complex, respectively. Notably, cobalt can reduce zinc demand and promote the growth ofP. aeruginosastrains unable to import zinc, highlighting pyochelin-mediated cobalt import as a novel bacterial strategy to counteract zinc deficiency. These results unveil an unexpected role for pyochelin in zinc homeostasis and challenge the traditional view of this metallophore exclusively as an iron transporter.
K48- and K63-linked ubiquitin chain interactome reveals branch- and chain length-specific ubiquitin interactors
Authors: Waltho Anita , Popp Oliver , Lenz Christopher , Pluska Lukas , Dötsch Volker , Mertins Phillip , Sommer Thomas
Published: January 2024

The ubiquitin (Ub) code denotes the complex Ub architectures, including Ub chains of different length, linkage-type and linkage combinations, which enable ubiquitination to control a wide range of protein fates. Although many linkage-specific interactors have been described, how interactors are able to decode more complex architectures is not fully understood. We conducted a Ub interactor screen, in humans and yeast, using Ub chains of varying length, as well as, homotypic and heterotypic branched chains of the two most abundant linkage types – K48- and K63-linked Ub. We identified some of the first K48/K63 branch-specific Ub interactors, including histone ADP-ribosyltransferase PARP10/ARTD10, E3 ligase UBR4 and huntingtin-interacting protein HIP1. Furthermore, we revealed the importance of chain length by identifying interactors with a preference for Ub3 over Ub2 chains, including Ub-directed endoprotease DDI2, autophagy receptor CCDC50 and p97-adaptor FAF1. Crucially, we compared datasets collected using two common DUB inhibitors – Chloroacetamide and N-ethylmaleimide. This revealed inhibitor-dependent interactors, highlighting the importance of inhibitor consideration during pulldown studies. This dataset is a key resource for understanding how the Ub code is read.
The suprapyramidal and infrapyramidal blades of the dentate gyrus exhibit different GluN subunit content and dissimilar frequency-dependent synaptic plasticity in vivo
Authors: Strauch Christina , Böge Juliane , Shchyglo Olena , Dubovyk Valentyna , Manahan-Vaughan Denise
Published: January 2024

The entorhinal cortex sends afferent information to the hippocampus by means of the perforant path(PP), whereby the medial PP (MPP) is believed to convey information about spatial context and the lateral PP (LPP) may convey information about item identity. This information is encoded by means of synaptic plasticity. The PP input to the dentate gyrus(DG) terminates in the suprapyramidal (upper/inner) and infrapyramidal (lower/outer) blades. To what extent frequency-dependent synaptic plasticity in these blades differs is unclear. Here, we compared MPP-DG responses in the supra- (sDG) and infrapyramidal blades (iDG) of freely behaving adult rats and found that synaptic plasticity in the sDG is broadly frequency-dependent whereby long-term depression (LTD, >24h) is induced with stimulation at 1Hz, short-term depression (<2h) is triggered by 5 or 10Hz and long-term potentiation (LTP) of increasing magnitudes is induced by 200 and 400 Hz stimulation, respectively. By contrast, although the iDG expresses STD following 5 or 10Hz stimulation, LTD induced by 1Hz is weaker, LTP is not induced by 200Hz and LTP induced by 400Hz stimulation is significantly smaller in magnitude and is less persistent (<4h) compared to LTP in sDG. Furthermore, the stimulus-response relationship of the iDG is suppressed compared to sDG. Patch clamp recordings, in vitro, revealed reduced firing frequencies in response to high currents, and different action potential thresholds in iDG compared to sDG. Assessment of the expression of GluN subunits revealed significantly lower expression levels of GluN1, GluN2A and GluN2B in iDG compared to sDG. Taken together, these data indicate that synaptic plasticity in the infrapyramidal blade of the dentate gyrus is weaker, less persistent and less responsive to afferent frequencies than synaptic plasticity in sDG. Effects may be mediated by weaker NMDA receptor expression in iDG. These characteristics may explain reported differences in experience-dependent information processing in sDG versus iDG.
The role of conscious attention in statistical learning: evidence from patients with impaired consciousness
Authors: Benjamin Lucas , Zang Di , Fló Ana , Qi Zengxin , Su Pengpeng , Zhou Wenya , Wang Liping , Wu Xuehai , Gui Peng , Dehaene-Lambertz Ghislaine
Published: January 2024

The debate over whether conscious attention is necessary for statistical learning has produced mixed and conflicting results. Testing individuals with impaired consciousness may provide some insight, but very few studies have been conducted due to the difficulties associated with testing such patients. In this study, we examined the ability of patients with varying levels of consciousness disorders (DOC), including coma, unresponsive wakefulness syndrome, minimally conscious patients, and emergence from minimally conscious state patients, to extract statistical regularities from an artificial language composed of four randomly concatenated pseudowords. We used a methodology based on frequency tagging in EEG, which was developed in our previous studies on speech segmentation in sleeping neonates. Our study had two main objectives: firstly, to assess the automaticity of the segmentation process and explore correlations between the level of covert consciousness and the abilities to extract statistical regularities, second, to explore a potential new diagnostic indicator to aid in patient management by examining the correlation between successful statistical learning markers and consciousness level. We observed that segmentation abilities were preserved in some minimally conscious patients, suggesting that statistical learning is an inherently automatic low-level process. Due to significant inter-individual variability, word segmentation may not be a sufficiently robust candidate for clinical use, unlike temporal accuracy of auditory syllable responses, which correlates strongly with coma severity. Therefore, we propose that frequency tagging of an auditory stimulus train, a simple and robust measure, should be further investigated as a possible metric candidate for DOC diagnosis.
Effect of RNA m6A methyltransferase activation by a low molecular weight compound on anxiety- and depression-related behaviours, monoamine neurochemistry and striatal gene expression in the rat
Authors: Kanarik Margus , Liiver Kristi , Školnaja Marianna , Teino Indrek , Org Tõnis , Laugus Karita , Shimmo Ruth , Karelson Mati , Saarma Mart , Harro Jaanus
Published: January 2024

Modification of mRNA by methylation is involved in post-transcriptional regulation of gene expression by affecting the splicing, transport, stability and translation of mRNA. Methylation of adenosine at N6(m6A) is the most common and most important cellular modification occurring in the mRNA of eukaryotes. Evidence that m6A mRNA methylation is involved in regulation of stress response and that its dysregulation may contribute to the pathogenesis of neuropsychiatric disorders is accumulating. We have examined the acute and subchronic (up to 18 days once per day intraperitoneally) effect of the first METTL3/METTL14 activator compound CHMA1004 (methyl-piperazine-2-carboxylate) at two doses (1 and 5 mg/kg) in male and female rats. CHMA1004 had a profound locomotor activating and anxiolytic-like profile in open field and elevated zero-maze tests. In female rats sucrose consumption and swimming in Porsolt’s test were increased. Nevertheless, CHMA1004 did not exhibit strong psychostimulant-like properties: CHMA1004 had no effect on 50-kHz ultrasonic vocalizations except that it reduced the baseline difference between male and female animals, and acute drug treatment had no effect on extracellular dopamine levels in striatum. Subchronic CHMA1004 alteredex vivocatecholamine levels in several brain regions. RNA sequencing of female rat striata after subchronic CHMA1004 treatment revealed changes in the expression of a number of genes linked to dopamine neuron viability, neurodegeneration, depression, anxiety and stress response. Conclusively, the first-in-class METTL3/METTL14 activator compound CHMA1004 increased locomotor activity and elicited anxiolytic-like effects after systemic administration, demonstrating tha pharmacological activation of RNA m6A methylation has potential for neuropsychiatric drug development.
Development of a 3D vascular network visualization platform for one-dimensional hemodynamic simulation
Authors: Chen Yan , Kobayashi Masaharu , Yuhn Changyoung , Oshima Marie
Published: January 2024

Recent advancements in computational performance and medical simulation technology, have made significant strides, particularly in predictive diagnosis. This study focuses on the blood flow simulation reduced-order models, which provide swift and cost-effective solutions for complex vascular systems, positioning them as practical alternatives to 3D simulations in resource-limited medical settings. The paper introduces a visualization platform for patient-specific and image-based 1D-0D simulations. This platform covers the entire workflow, from modeling to dynamic 3D visualization of simulation results. Two case studies on respectively carotid stenosis and arterial remodeling demonstrate its utility in surgical planning and preventing complications like cerebral hyperperfusion syndrome.
Changes in enclosure use and basking behaviour associated with pair housing in Tokay geckos (Gekko gecko)
Authors: Szabo Birgit
Published: January 2024

Due to often insufficient information reptiles suffer welfare issues and increased mortality in captivity. In particular, the impact of the social environment remains poorly understood, despite evidence suggesting its’ importance for welfare in a wide range social animals. The current study investigated how pair housing changes enclosure use, basking and hiding behaviour in tokay geckos (Gekko gecko). While the captive conditions and husbandry procedures employed in this study align with existing literature recommendations, they have not been previously evaluated for their suitability for this particular species. The results show that, when socially deprived, lizards were more likely to move and hide before feeding. Furthermore, males were more likely to be found at the front than females during pair housing but not during single housing. Finally, contrary to single housing, enclosure temperature had no effect on the probability to move and hide behind a shelter during pair housing. Consistently, however, lizards were more likely to bask after feeding across housing conditions and females were more likely to bask before their first clutch. Together, pair housing decreases movement and hiding in relation to human presence (feeding) which might indicate that pair housing improves tokay gecko welfare and suggest that the presence of a conspecific should be considered to improve welfare policies in social reptiles. This study serves as a baseline for future research into how enclosure furnishings, husbandry techniques, and enrichment practices impact the welfare of tokay geckos which will be crucial for refining our understanding of and improving on the welfare of reptiles in captivity.
Bioinformatic analysis of sulfotransferases from an unexplored gut microbe,Sutterella wadsworthensis 3_1_45B: Possible roles towards detoxification via sulfation by the members of the human gut microbiome
Authors: Langford Lauryn , Shah Dhara D.
Published: January 2024

Sulfation, primarily facilitated by sulfotransferases, plays a crucial role in the detoxification pathways of both endogenous substances and xenobiotics, enhancing their water solubility and promoting metabolism and elimination. Traditionally, this bioconversion has been attributed to a family of human cytosolic sulfotransferases (hSULTs) known for their high sequence similarity and dependence on 3’-phosphoadenosine 5’-phosphosulfate (PAPS) as a sulfate donor. However, recent studies have revealed the presence of PAPS-dependent sulfotransferases within gut commensals, indicating that the gut microbiome may harbor a diverse array of sulfotransferase enzymes and may contribute to detoxification processes via sulfation. In this study, we investigated the prevalence of sulfotransferases in the members of the human gut microbiome. Interestingly, we stumbled upon a different class of sulfotransferases, known as aryl-sulfate sulfotransferases (ASSTs). ASSTs have been characterized from a few different prokaryotes includingE. coli. ASSTs do not utilize PAPS which is the default sulfate donor for the human sulfotransferases. Our bioinformatics analyses revealed that the gut microbial genusSutterellapossesses a significant number ofasstgenes, possibly encoding multiple ASST enzymes. Fluctuations in the microbes of the genusSutterellahave been associated with various health conditions. For this reason, we characterized 17 different ASSTs fromSutterella wadsworthensis 3_1_45Bwith bioinformatics. Our findings reveal thatSwASSTs share similarities withE. coliASST but also exhibit significant structural variations and sequence diversity. These differences might drive potential functional diversification and likely reflect an evolutionary divergence from their PAPS-dependent counterparts.
Calculation of space-charge tune shift in a cylindrical chamber for bunched beams employing Green’s function formalism
Authors: Shobuda Yoshihiro
Published: January 2024

When computing the space-charge tune shift for a relativistic bunched beam within a cylindrical chamber, mirror currents for a coasting beam, initially introduced to replace the chamber wall, are employed. Subsequently, the obtained result is extended to encompass the bunched beam, taking into account the bunching factor which quantifies the distribution of bunches around the accelerator ring. In the process of derivation, the terms that characterize the bunch length are intuitively integrated into the formula. As a result, the validity of this approach has never been established. This study provides the derivation of the space-charge tune shift formula for both relativistic and nonrelativistic bunched beams right from the outset, employing the Green function formalism. Subsequently, it is compared with the earlier formula derived using mirror currents.

Published by the American Physical Society
2024
Charmless
B→PPP
decays: The fully antisymmetric final state
Authors: Bhattacharya Bhubanjyoti , Fines-Neuschild Mirjam , Houck Andrea , Imbeault Maxime , Jean Alexandre , London David
Published: January 2024

Under flavor SU(3) symmetry (SU(3)F), the final-state particles in B→PPP decays (P is a pseudoscalar meson) are treated as identical, and the PPP must be in a fully-symmetric (FS) state, a fully-antisymmetric (FA) state, or in one of four mixed states. In this paper, we present the formalism for the FA states. We write the amplitudes for the

22

B

→

P

P

P

decays that can be in an FA state in terms of both the SU(3)F reduced matrix elements and diagrams. This shows the equivalence of diagrams and SU(3)F. We also give 15 relations among the amplitudes in the SU(3)F limit as well as the additional four that appear when the diagrams E/A/PA are neglected. We present sets of B→PPP decays that can be used to extract γ using the FA amplitudes. The value(s) of γ found in this way can be compared with the value(s) found using the FS states.

Published by the American Physical Society
2024
Single phonon detection for dark matter via quantum evaporation and sensing of
He3
Authors: Lyon S. A. , Castoria Kyle , Kleinbaum Ethan , Qin Zhihao , Persaud Arun , Schenkel Thomas , Zurek Kathryn M.
Published: January 2024

Dark matter is five times more abundant than ordinary visible matter in our Universe. While laboratory searches hunting for dark matter have traditionally focused on the electroweak scale, theories of low mass hidden sectors motivate new detection techniques. Extending these searches to lower mass ranges, well below 1  GeV/c2, poses new challenges as rare interactions with standard model matter transfer progressively less energy to electrons and nuclei in detectors. Here, we propose an approach based on phonon-assisted quantum evaporation combined with quantum sensors for detection of desorption events via tracking of spin coherence. The intent of our proposed dark matter sensors is to extend the parameter space to energy transfers in rare interactions to as low as a few meV for detection of dark matter particles in the keV/c2 mass range.

Published by the American Physical Society
2024
Finite-key analysis for coherent one-way quantum key distribution
Authors: Li Ming-Yang , Cao Xiao-Yu , Xie Yuan-Mei , Yin Hua-Lei , Chen Zeng-Bing
Published: January 2024

Coherent-one-way (COW) quantum key distribution (QKD) is a significant communication protocol that has been implemented experimentally and deployed in practical products due to its simple equipment requirements. However, existing security analyses of COW-QKD either provide a short transmission distance or lack immunity against coherent attacks in the finite-key regime. In this paper, we present a tight finite-key security analysis within the universally composable framework for a variant of COW-QKD, which has been proven to extend the secure transmission distance in the asymptotic case. We combine the quantum leftover hash lemma and entropic uncertainty relation to derive the key rate formula. When estimating statistical parameters, we use the recently proposed Kato's inequality to ensure security against coherent attacks and achieve a higher key rate. Our paper confirms the security and feasibility of COW-QKD for practical application and lays the foundation for further theoretical study and experimental implementation.

Published by the American Physical Society
2024
Investigation on laser absorption and x-ray radiation in microstructured titanium targets heated by short-pulse relativistic laser pulses
Authors: Pan X. , Šmíd M. , Huang L. G. , Kluge T. , Bagnoud V. , Brambrink E. , Cowan T. E. , Colgan J. , Ebert T. , Hartnagel D. , Hesse M. , Hornung J. , Kleinschmidt A. , Perez-Martin P. , Neukirch A. , Philipp K. , Sander S. , Schaumann G. , Tebartz A. , Zielbauer B. , Roth M. , Falk K.
Published: January 2024

The enhancement effect of a microstructured surface on laser absorption and characteristic Kα emission has been investigated by measuring K-shell emission from titanium (Ti) targets irradiated with high-intensity (∼1020Wcm−2), subpicosecond (500 fs) laser pulses. The experimental results indicate a modest enhancement (1.6×) of Kα emission from microstructured targets compared to flat foils, but with a similar intensity and profile of Heα and Li-like satellites. Particle-in-cell (PIC) simulations are implemented to further understand the underlying physical processes in the laser interaction with both targets, interpreting the mechanisms responsible for the Kα enhancement. The reasons for the lower-than-expected enhancement of Kα emission are discussed. The rapid heating of the bulk plasma might result in the premature shutdown of Kα emission before the thermalization of hot electrons or even the end of laser pulses, suggesting that the use of

K

α

emission as a diagnostic of the hot-electron yield or relaxation could lead to a misinterpretation.

Published by the American Physical Society
2024
Telecom Networking with a Diamond Quantum Memory
Authors: Bersin Eric , Sutula Madison , Huan Yan Qi , Suleymanzade Aziza , Assumpcao Daniel R. , Wei Yan-Cheng , Stas Pieter-Jan , Knaut Can M. , Knall Erik N. , Langrock Carsten , Sinclair Neil , Murphy Ryan , Riedinger Ralf , Yeh Matthew , Xin C.J. , Bandyopadhyay Saumil , Sukachev Denis D. , Machielse Bartholomeus , Levonian David S. , Bhaskar Mihir K. , Hamilton Scott , Park Hongkun , Lončar Marko , Fejer Martin M. , Dixon P. Benjamin , Englund Dirk R. , Lukin Mikhail D.
Published: January 2024

Practical quantum networks require interfacing quantum memories with existing channels and systems that operate in the telecom band. Here we demonstrate low-noise, bidirectional quantum frequency conversion that enables a solid-state quantum memory to directly interface with telecom-band systems. In particular, we demonstrate conversion of visible-band single photons emitted from a silicon-vacancy (SiV) center in diamond to the telecom O band, maintaining low noise (g2(0)<0.1) and high indistinguishability (

V

=

89

±

8

%

). We further demonstrate the utility of this system for quantum networking by converting telecom-band time-bin pulses, sent across a lossy and noisy 50-km deployed fiber link, to the visible band and entangling them with a diamond quantum memory with fidelity F≥87±2.5%. These results demonstrate the viability of SiV quantum memories integrated with telecom-band systems for scalable quantum networking applications.

Published by the American Physical Society
2024
Aero-spike and aero-disk effects of on wave drag reduction of supersonic flow past over blunt body
Authors: Balusamy Kathiravan , A. Vinothraj , V. Suresh
Published: January 2024

Purpose

The purpose of this study is to explore the effects of aerospike and hemispherical aerodisks on flow characteristics and drag reduction in supersonic flow over a blunt body. Specifically, the study aims to analyze the impact of varying the length of the cylindrical rod in the aerospike (ranging from 0.5 to 2.0 times the diameter of the blunt body) and the diameter of the hemispherical disk (ranging from 0.25 to 0.75 times the blunt body diameter). CFD simulations were conducted at a supersonic Mach number of 2 and a Reynolds number of 2.79 × 106.

Design/methodology/approach

ICEM CFD and ANSYS CFX solver were used to generate the three-dimensional flow along with its structures. The flow structure and drag coefficient were computed using Reynolds-averaged Navier–Stokes equation model. The drag reduction mechanism was also explained using the idea of dividing streamline and density contour. The performance of the aero spike length and the effect of aero disk size on the drag are investigated.

Findings

The separating shock is located in front of the blunt body, forming an effective conical shape that reduces the pressure drag acting on the blunt body. It was observed that extending the length of the spike beyond a specific critical point did not impact the flow field characteristics and had no further influence on the enhanced performance. The optimal combination of disk and spike length was determined, resulting in a substantial reduction in drag through the introduction of the aerospike and disk.

Research limitations/implications

To predict the accurate results of drag and to reduce the simulation time, a hexa grid with finer mesh structure was adopted in the simulation.

Practical implications

The blunt nose structures are primarily employed in the design of rockets, missiles, and re-entry capsules to withstand higher aerodynamic loads and aerodynamic heating.

Originality/value

For the optimized size of the aero spike, aero disk is also optimized to use the benefits of both.
Technological competitiveness of China's internet platformers: comparison of Google and Baidu by using patent text information
Authors: Motohashi Kazuyuki , Zhu Chen
Published: January 2024

Purpose

This study aims to assess the technological capability of Chinese internet platforms (BAT: Baidu, Alibaba, Tencent) compared to US ones (GAFA: Google, Amazon, Facebook, Apple). More specifically, this study explores Baidu’s technological catching-up process with Google by analyzing their patent textual information.

Design/methodology/approach

The authors retrieved 26,383 Google patents and 6,695 Baidu patents from PATSTAT 2019 Spring version. The collected patent documents were vectorized using the Word2Vec model first, and then K-means clustering was applied to visualize the technological space of two firms. Finally, novel indicators were proposed to capture the technological catching-up process between Baidu and Google.

Findings

The results show that Baidu follows a trend of US rather than Chinese technology which suggests Baidu is aggressively seeking to catch up with US players in the process of its technological development. At the same time, the impact index of Baidu patents increases over time, reflecting its upgrading of technological competitiveness.

Originality/value

This study proposed a new method to analyze technology mapping and evolution based on patent text information. As both US and China are crucial players in the internet industry, it is vital for policymakers in third countries to understand the technological capacity and competitiveness of both countries to develop strategic partnerships effectively.
Development of a project complexity measurement model for metro rail projects
Authors: Sruthilaya Dara , Vilventhan Aneetha , Gopal P.R.C.
Published: January 2024

Purpose

The purpose of this research is to develop a project complexity index (PCI) model using the best and worst method (BWM) to quantitatively analyze the impact of project complexities on the performance of metro rail projects.

Design/methodology/approach

This study employed a two-phase research methodology. The first phase identifies complexities through a literature review and expert discussions and categorizes different types of complexities in metro rail projects. In the second phase, BWM, a robust multi-criteria decision-making (MCDM) technique, was used to prioritize key complexities, and a PCI model was developed. Further, the developed PCI was validated through case studies, and sensitivity analysis was performed to check the accuracy and applicability of the developed PCI model.

Findings

The analysis revealed that location complexity exerted the most substantial influence on project performance, followed by environmental, organizational, technological and contractual complexities. Sensitivity analysis revealed the varying impacts of complexity indices on the overall project complexity.

Practical implications

The study's findings offer a novel approach for measuring project complexity's impact on metro rail projects. This allows stakeholders to make informed decisions, allocate resources efficiently and plan strategically.

Originality/value

The existing studies on project complexity identification and quantification were limited to megaprojects other than metro rail projects. Efforts to quantitatively study and analyze the impact of project complexity on metro rail projects are left unattended. The developed PCI model and its validation contribute to the field by providing a definite method to measure and manage complexity in metro rail projects.
Numerical simulation of entropy generation in thermo-magnetic convection in an inverted T-shaped porous enclosure under thermal radiation
Authors: Kumar Sumant , Rathish Kumar B.V. , Krishna Murthy S.V.S.S.N.V.G. , Parmar Deepika
Published: January 2024

Purpose

Thermo-magnetic convective flow analysis under the impact of thermal radiation for heat and entropy generation phenomena is an active research field for understanding the efficiency of thermodynamic systems in various engineering sectors. This study aims to examine the characteristics of convective heat transport and entropy generation within an inverted T-shaped porous enclosure saturated with a hybrid nanofluid under the influence of thermal radiation and magnetic field.

Design/methodology/approach

The mathematical model incorporates the Darcy-Forchheimer-Brinkmann model and considers thermal radiation in the energy balance equation. The complete mathematical model has been numerically simulated through the penalty finite element approach at varying values of flow parameters, such as Rayleigh number (Ra), Hartmann number (Ha), Darcy number (Da), radiation parameter (Rd) and porosity value (e). Furthermore, the graphical results for energy variation have been monitored through the energy-flux vector, whereas the entropy generation along with its individual components, namely, entropy generation due to heat transfer, fluid friction and magnetic field, are also presented. Furthermore, the results of the Bejan number for each component are also discussed in detail. Additionally, the concept of ecological coefficient of performance (ECOP) has also been included to analyse the thermal efficiency of the model.

Findings

The graphical analysis of results indicates that higher values of Ra, Da, e and Rd enhance the convective heat transport and entropy generation phenomena more rapidly. However, increasing Ha values have a detrimental effect due to the increasing impact of magnetic forces. Furthermore, the ECOP result suggests that the rising value of Da, e and Rd at smaller Ra show a maximum thermal efficiency of the mathematical model, which further declines as the Ra increases. Conversely, the thermal efficiency of the model improves with increasing Ha value, showing an opposite trend in ECOP.

Practical implications

Such complex porous enclosures have practical applications in engineering and science, including areas like solar power collectors, heat exchangers and electronic equipment. Furthermore, the present study of entropy generation would play a vital role in optimizing system performance, improving energy efficiency and promoting sustainable engineering practices during the natural convection process.

Originality/value

To the best of the authors’ knowledge, this study is the first ever attempted detailed investigation of heat transfer and entropy generation phenomena flow parameter ranges in an inverted T-shaped porous enclosure under a uniform magnetic field and thermal radiation.
Magnetotactic bacteria and Fe3O4–water in a wavy walled cavity
Authors: Pekmen Geridonmez Bengisen , Oztop Hakan
Published: January 2024

Purpose

The purpose of this study is to investigate the interaction between magnetotactic bacteria and Fe3O4–water nanofluid (NF) in a wavy enclosure in the presence of 2D natural convection flow.

Design/methodology/approach

Uniform magnetic field (MF), Brownian and thermophoresis effects are also contemplated. The dimensionless, time-dependent equations are governed by stream function, vorticity, energy, nanoparticle concentration and number of bacteria. Radial basis function-based finite difference method for the space derivatives and the second-order backward differentiation formula for the time derivatives are performed. Numerical outputs in view of isolines as well as average Nusselt number, average Sherwood number and flux density of microorganisms are presented.

Findings

Convective mass transfer rises if any of Lewis number, Peclet number, Rayleigh number, bioconvection Rayleigh number and Brownian motion parameter increases, and the flux density of microorganisms is an increasing function of Rayleigh number, bioconvection Rayleigh number, Peclet number, Brownian and thermophoresis parameters. The rise in buoyancy ratio parameter between 0.1 and 1 and the rise in Hartmann number between 0 and 50 reduce all outputs average Nusselt, average Sherwood numbers and flux density of microorganisms.

Research limitations/implications

This study implies the importance of the presence of magnetotactic bacteria and magnetite nanoparticles inside a host fluid in view of heat transfer and fluid flow. The limitation is to check the efficiency on numerical aspect. Experimental observations would be more effective.

Practical implications

In practical point of view, in a heat transfer and fluid flow system involving magnetite nanoparticles, the inclusion of magnetotactic bacteria and MF effect provide control over fluid flow and heat transfer.

Social implications

This is a scientific study. However, this idea may be extended to sustainable energy or biofuel studies, too. This means that a better world may create better social environment between people.

Originality/value

The presence of magnetotactic bacteria inside a Fe3O4–water NF under the effect of a MF is a good controller on fluid flow and heat transfer. Since the magnetotactic bacteria is fed by nanoparticles Fe3O4 which has strong magnetic property, varying nanoparticle concentration and Brownian and thermophoresis effects are first considered.
The impact of institutional pressures on corporate social responsibility and green marketing adoption: an empirical approach in Vietnam banking industry
Authors: Huynh Anh-Tuan , Knápková Adriana , Bui Tat-Dat , Nguyen Tran-Thai-Ha
Published: January 2024

Purpose

Institutional pressure and corporate social responsibility (CSR) are gaining increasing recognition in scholarly works; however, there is an apparent and unsettled relationship between these concepts and the concept of green marketing adoption (GMA) that influences efforts to gain a relative competitive advantage (RCA). This study is aimed at examining the roles of institutional pressure and CSR on GMA and RCA and proposes recommendations for promoting green marketing management and CSC in the banking industry in Vietnam.

Design/methodology/approach

In this study, partial least squares structural equation modeling is utilized to investigate the evolution of the structural model, while the hypotheses are evaluated using structural equation modeling (SEM). The data are scrutinized from 288 banking employees through an online survey.

Findings

The results show that the components of institutional pressure exert a significant impact on GMA and RCA, but the level and type of this impact differ. Additionally, the mediating role of the CSR variable in this relationship is revealed. Under the influence of institutional pressure, companies tend to increase their implementation of CSR activities, thereby promoting their GMA and RCA.

Originality/value

This study offers both theoretical and practical implications. Theoretically, this study adds to the extant evidence concerning the significance of CSR integration and institutional pressure to the advancement of GMA. In addition, maintaining a focus on fostering holistic GMA practices has enabled the banking industry in Vietnam to achieve an RCA.
Brand portfolio extension of international hotel chains: a perspective on consumer confusion and consumer decision-making process
Authors: Kim Jinkyung Jenny
Published: January 2024

Purpose

This study aims to pay attention to the brand portfolio extension of international hotel chains, and explores the double-edged sword effect of consumer confusion in hotel brands on the purchase decision process.

Design/methodology/approach

Four representative international hotel chains (Marriott, Accor, Wyndham and Hyatt) were selected, and this study adopted consumer confusion from both formative and reflective perspectives. First, the authors dealt with stimuli-causing consumer confusion and evaluated similarity, overload and ambiguity confusion about the brand portfolio of these major hotel companies. Second, the authors examined the influence of consumer confusion on the decision-making process, which is rooted in the awareness–interest–desire–action model.

Findings

Among the source of consumer confusion, similarity confusion was critical for Marriott, Accor and Hyatt, whereas ambiguity confusion was severe for Wyndham. Awareness was positively affected by overload confusion, but negatively affected by ambiguity confusion. Furthermore, the link between interest and desire was moderated by the consequences of consumer confusion.

Practical implications

Based on both positive and negative roles of consumer confusion, this study provides implications for enhancing brand strategy and communications of international chain hotels.

Originality/value

This present study differs from previous studies, in that it deals with consumer confusion associated with brand portfolio expansion, which produces a double-edged sword effect in the hotel context.