bluuebunny/crossref_metadata_2025 huggingface dataset:
Technical Aspects of Eliciting Trigeminocervical and Trigeminospinal Reflexes in Humans: A Scoping Review
Authors: Melo Denise Lima Medeiros de , Comerlato Enio Alberto , Pinheiro Denise Spinola , Manzano Gilberto Mastrocola
Published: February 2024

This scoping review aims to summarize the technical strategies for obtaining trigeminocervical reflex (TCR) and trigeminospinal reflex (TSR) responses. Studies published on TCR or TSR elicitation in humans through electrical stimulation of trigeminal nerve branches were eligible for this scoping review. The data of interest included stimulation parameters, site of stimulation, recording parameters, and the feasibility of TCR and TSR elicitation, in healthy participants. Short-latency TCR responses were regularly obtained in both anterior and posterior neck muscles after electrical stimulation of the supraorbital and infraorbital nerves under voluntary muscle activation. However, without voluntary muscle activation, we found evidence of elicitation of short-latency TCR components only in the posterior neck muscles after supraorbital or infraorbital nerve stimulation. Long-latency TCR responses were regularly obtained in the anterior and posterior neck muscles in studies that evaluated this technique, regardless of the trigeminal branch stimulation or muscle activation status. Short-latency TSR components were not obtained in the included studies, whereas long-latency TSR responses were regularly recorded in proximal upper limb muscles. This scoping review revealed key heterogeneity in the techniques used for TCR and TSR elicitation. By summarizing all the methodological procedures used for TCR and TSR elicitation, this scoping review can guide researchers in defining optimized technical approaches for different research and clinical scenarios.
Real-Time Seizure Detection Using Behind-the-Ear Wearable System
Authors: Lehnen Jamie , Venkatesh Pooja , Yao Zhuoran , Aziz Abdul , Nguyen Phuc V.P. , Harvey Jay , Alick-Lindstrom Sasha , Doyle Alex , Podkorytova Irina , Perven Ghazala , Hays Ryan , Zepeda Rodrigo , Das Rohit R. , Ding Kan
Published: February 2024

Introduction:

This study examines the usability and comfort of a behind-the-ear seizure detection device called brain seizure detection (BrainSD) that captures ictal electroencephalogram (EEG) data using four scalp electrodes.

Methods:

This is a feasibility study. Thirty-two patients admitted to a level 4 Epilepsy Monitoring Unit were enrolled. The subjects wore BrainSD and the standard 21-channel video-EEG simultaneously. Epileptologists analyzed the EEG signals collected by BrainSD and validated it using video-EEG data to confirm its accuracy. A poststudy survey was completed by each participant to evaluate the comfort and usability of the device. In addition, a focus group of UT Southwestern epileptologists was held to discuss the features they would like to see in a home EEG-based seizure detection device such as BrainSD.

Results:

In total, BrainSD captured 11 of the 14 seizures that occurred while the device was being worn. All 11 seizures captured on BrainSD had focal onset, with three becoming bilateral tonic-clonic and one seizure being of subclinical status. The device was worn for an average of 41 hours. The poststudy survey showed that most users found the device comfortable, easy-to-use, and stated they would be interested in using BrainSD. Epileptologists in the focus group expressed a similar interest in BrainSD.

Conclusions:

Brain seizure detection is able to detect EEG signals using four behind-the-ear electrodes. Its comfort, ease-of-use, and ability to detect numerous types of seizures make BrainSD an acceptable at-home EEG detection device from both the patient and provider perspective.
The long and short of it: benchmarking viromics using Illumina, Nanopore and PacBio sequencing technologies
Authors: Cook Ryan , Brown Nathan , Rihtman Branko , Michniewski Slawomir , Redgwell Tamsin , Clokie Martha , Stekel Dov J. , Chen Yin , Scanlan David J. , Hobman Jon L. , Nelson Andrew , Jones Michael A. , Smith Darren , Millard Andrew
Published: February 2024

Viral metagenomics has fuelled a rapid change in our understanding of global viral diversity and ecology. Long-read sequencing and hybrid assembly approaches that combine long- and short-read technologies are now being widely implemented in bacterial genomics and metagenomics. However, the use of long-read sequencing to investigate viral communities is still in its infancy. While Nanopore and PacBio technologies have been applied to viral metagenomics, it is not known to what extent different technologies will impact the reconstruction of the viral community. Thus, we constructed a mock bacteriophage community of previously sequenced phage genomes and sequenced them using Illumina, Nanopore and PacBio sequencing technologies and tested a number of different assembly approaches. When using a single sequencing technology, Illumina assemblies were the best at recovering phage genomes. Nanopore- and PacBio-only assemblies performed poorly in comparison to Illumina in both genome recovery and error rates, which both varied with the assembler used. The best Nanopore assembly had errors that manifested as SNPs and INDELs at frequencies 41 and 157 % higher than found in Illumina only assemblies, respectively. While the best PacBio assemblies had SNPs at frequencies 12 and 78 % higher than found in Illumina-only assemblies, respectively. Despite high-read coverage, long-read-only assemblies recovered a maximum of one complete genome from any assembly, unless reads were down-sampled prior to assembly. Overall the best approach was assembly by a combination of Illumina and Nanopore reads, which reduced error rates to levels comparable with short-read-only assemblies. When using a single technology, Illumina only was the best approach. The differences in genome recovery and error rates between technology and assembler had downstream impacts on gene prediction, viral prediction, and subsequent estimates of diversity within a sample. These findings will provide a starting point for others in the choice of reads and assembly algorithms for the analysis of viromes.
A validated pangenome-scale metabolic model for the Klebsiella pneumoniae species complex
Authors: Cooper Helena B. , Vezina Ben , Hawkey Jane , Passet Virginie , López-Fernández Sebastián , Monk Jonathan M. , Brisse Sylvain , Holt Kathryn E. , Wyres Kelly L.
Published: February 2024

The Klebsiella pneumoniae species complex (KpSC) is a major source of nosocomial infections globally with high rates of resistance to antimicrobials. Consequently, there is growing interest in understanding virulence factors and their association with cellular metabolic processes for developing novel anti-KpSC therapeutics. Phenotypic assays have revealed metabolic diversity within the KpSC, but metabolism research has been neglected due to experiments being difficult and cost-intensive. Genome-scale metabolic models (GSMMs) represent a rapid and scalable in silico approach for exploring metabolic diversity, which compile genomic and biochemical data to reconstruct the metabolic network of an organism. Here we use a diverse collection of 507 KpSC isolates, including representatives of globally distributed clinically relevant lineages, to construct the most comprehensive KpSC pan-metabolic model to date, KpSC pan v2. Candidate metabolic reactions were identified using gene orthology to known metabolic genes, prior to manual curation via extensive literature and database searches. The final model comprised a total of 3550 reactions, 2403 genes and can simulate growth on 360 unique substrates. We used KpSC pan v2 as a reference to derive strain-specific GSMMs for all 507 KpSC isolates, and compared these to GSMMs generated using a prior KpSC pan-reference (KpSC pan v1) and two single-strain references. We show that KpSC pan v2 includes a greater proportion of accessory reactions (8.8 %) than KpSC pan v1 (2.5 %). GSMMs derived from KpSC pan v2 also generate more accurate growth predictions, with high median accuracies of 95.4 % (aerobic, n=37 isolates) and 78.8 % (anaerobic, n=36 isolates) for 124 matched carbon substrates. KpSC pan v2 is freely available at https://github.com/kelwyres/KpSC-pan-metabolic-model, representing a valuable resource for the scientific community, both as a source of curated metabolic information and as a reference to derive accurate strain-specific GSMMs. The latter can be used to investigate the relationship between KpSC metabolism and traits of interest, such as reservoirs, epidemiology, drug resistance or virulence, and ultimately to inform novel KpSC control strategies.
Robust SARS-CoV-2 Neutralizing Antibodies Sustained through Three Months Post XBB.1.5 mRNA Vaccine Booster
Authors: Wang Qian , Mellis Ian A , Guo Yicheng , Gherasim Carmen , Valdez Riccardo , Gordon Aubree , Liu Lihong , Ho David D
Published: February 2024

SARS-CoV-2-neutralizing antibodies were substantially expanded one month after a shot of XBB.1.5 monovalent mRNA vaccine (XBB.1.5 MV) booster, but the durability of this response remained unknown. Here, we addressed this question by performing neutralization assays on four viral variants (D614G, BA.5, XBB.1.5, and JN.1) using sera from 39 adult participants obtained at ~1 month and ~3 months post an XBB.1.5 MV booster. Our findings indicate that the resultant neutralizing antibody titers were robust and generally maintained at stable levels for the study period, similar to those following XBB infection. Importantly, this durability of neutralizing antibody titers contrasts with the decline observed after a booster of the original monovalent or BA.5 bivalent mRNA vaccine. Our results are in line with the recent national data from the Centers for Disease Control and Prevention, showing the efficacy against symptomatic SARS-CoV-2 infection is sustained for up to 4 months after an XBB.1.5 MV booster.
A genome-wide arrayed CRISPR screen identifies PLSCR1 as an intrinsic barrier to SARS-CoV-2 entry that recent virus variants have evolved to resist
Authors: Le Pen Jérémie , Paniccia Gabrielle , Kinast Volker , Moncada-Velez Marcela , Ashbrook Alison W. , Bauer Michael , Hoffmann H.-Heinrich , Pinharanda Ana , Ricardo-Lax Inna , Stenzel Ansgar F. , Rosado-Olivieri Edwin A. , Dinnon Kenneth H. , Doyle William C. , Freije Catherine A. , Hong Seon-Hui , Lee Danyel , Lewy Tyler , Luna Joseph M. , Peace Avery , Schmidt Carltin , Schneider William M. , Winkler Roni , Yip Elaine Z. , Larson Chloe , McGinn Timothy , Menezes Miriam-Rose , Ramos-Espiritu Lavoisier , Banerjee Priyam , Poirier John T. , Sànchez-Rivera Francisco J. , Cobat Aurélie , Zhang Qian , Casanova Jean-Laurent , Carroll Thomas S. , Glickman J. Fraser , Michailidis Eleftherios , Razooky Brandon , MacDonald Margaret R. , Rice Charles M.
Published: February 2024

Interferons (IFNs) play a crucial role in the regulation and evolution of host-virus interactions. Here, we conducted a genome-wide arrayed CRISPR knockout screen in the presence and absence of IFN to identify human genes that influence SARS-CoV-2 infection. We then performed an integrated analysis of genes interacting with SARS-CoV-2, drawing from a selection of 67 large-scale studies, including our own. We identified 28 genes of high relevance in both human genetic studies of COVID-19 patients and functional genetic screens in cell culture, with many related to the IFN pathway. Among these was the IFN-stimulated genePLSCR1. PLSCR1 did not require IFN induction to restrict SARS-CoV-2 and did not contribute to IFN signaling. Instead, PLSCR1 specifically restricted spike-mediated SARS-CoV-2 entry. The PLSCR1-mediated restriction was alleviated by TMPRSS2 over-expression, suggesting that PLSCR1 primarily restricts the endocytic entry route. In addition, recent SARS-CoV-2 variants have adapted to circumvent the PLSCR1 barrier via currently undetermined mechanisms. Finally, we investigate the functional effects of PLSCR1 variants present in humans and discuss an association between PLSCR1 and severe COVID-19 reported recently.
Warfarin analogs target disulfide bond-forming enzymes and suggest a residue important for quinone and coumarin binding
Authors: Chavez Dariana , Amarquaye Gwendolyn Nita , Mejia-Santana Adrian , Dyotima  , Ryan Kayley , Zeng Lifan , Landeta Cristina
Published: February 2024

Disulfide bond formation has a central role in protein folding of both eukaryotes and prokaryotes. DsbB and VKOR enzymes catalyze the oxidation of the oxidoreductase partner and the formation of de novo disulfide bonds using quinone as cofactor. We have used E. coli and a family of warfarin analogs to study de novo disulfide bond formation. We found that human VKORc1 can function in E. coli by removing two positive residues, allowing the search for novel anticoagulants. One analog was capable of inhibiting both bacterial DsbB and VKOR, and a second one antagonized only the mammalian enzymes. We identified the two amino acid residues responsible for binding. One of these is also essential for quinone binding in both DsbB and VKOR. Our studies highlight a conserved role of this residue in de novo disulfide-generating enzymes and enable the design of novel anticoagulants or antibacterials using coumarin as a scaffold.
Journey to the center of the phage; revealing the ejectosome of Pectobacterium bacteriophage ΦM1
Authors: Eruera Alice-Roza , Hodgkinson-Bean James , Rutter Georgia L , Hills Francesca R , Kumaran Rosheny , Crowe Alexander J.M. , Jadav Nickhil , McJarrow-Keller Klemens Leo , Jorge Fatima Esperanca , Hyun Jaekyung , Kim Hyejin , Ryu Bumhan , Bostina Mihnea
Published: February 2024

Podophages that infect gram-negative bacteria, such as Pectobacterium pathogen PhiM1, encode tail assemblies too short to extend across the complex gram-negative cell wall. To overcome this, podophages encode a large protein complex (ejectosome) packaged inside the viral capsid and correspondingly ejected during infection to form a transient channel that spans the periplasmic space. Here we describe the ejectosome of bacteriophage PhiM1 to a resolution of 3.32 angstroms by single particle cryo-EM. The core consists of tetrameric and octameric ejection proteins which form a ~1.5 MDa ejectosome that must transition through the ~30 angstrom aperture created by the short tail nozzle assembly that acts as the conduit for the passage of DNA during infection. The ejectosome forms several grooves into which coils of genomic DNA are fit before the DNA sharply turns and goes down the tunnel and into the portal. In addition, we reconstructed the icosahedral capsid and hybrid tail apparatus to resolutions between 3.04 angstroms and 3.23 angstroms, and note an uncommon fold adopted by the dimerised decoration proteins which further emphasize the structural diversity of podophages. These reconstructions have allowed the generation of a complete atomic model of the PhiM1 particle, uncovering two distinct decoration proteins and highlighting the exquisite structural diversity of tailed bacteriophages.
tRNA hypomodification facilitates 5-fluorocytosine resistance via cross-pathway control system activation inAspergillus fumigatus
Authors: Bruch Alexander , Lazarova Valentina , Berg Maximilian , Krüger Thomas , Schäuble Sascha , Kelani Abdulrahman A. , Mertens Birte , Lehenberger Pamela , Kniemeyer Olaf , Kaiser Stefanie , Panagiotou Gianni , Gsaller Fabio , Blango Matthew G.
Published: February 2024

Increasing antifungal drug resistance is a major concern associated with human fungal pathogens likeAspergillus fumigatus. Genetic mutation and epimutation mechanisms clearly drive resistance, yet the epitranscriptome remains relatively untested. Here, deletion of theA. fumigatustRNA-modifying isopentenyl transferase ortholog, Mod5, led to altered stress response and unexpected resistance against the antifungal drug 5-fluorocytosine (5-FC). After confirming the canonical isopentenylation activity of Mod5 by LC-MS/MS and Nano-tRNAseq, we performed simultaneous profiling of transcriptomes and proteomes to reveal a comparable overall response to 5-FC stress; however, a premature activation of cross-pathway control (CPC) genes in the knockout was further increased after antifungal treatment. We identified several orthologues of theA. nidulansMajor Facilitator Superfamily (MFS) transporternmeAas specific CPC-client genes inA. fumigatus. Overexpression of Mod5-target tRNATyrGΨAin the Δmod5strain rescued select phenotypes but failed to reverse 5-FC resistance, whereas deletion ofnmeAlargely, but incompletely, reverted the resistance phenotype, implying additional relevant exporters. In conclusion, 5-FC resistance in the absence of Mod5 and i6A likely originates from multifaceted transcriptional and translational changes that skew the fungus towards premature CPC-dependent activation of antifungal toxic-intermediate exporternmeA, offering a potential mechanism reliant on RNA modification to facilitate transient antifungal resistance.
Structural basis of Ebola virus nucleocapsid assembly and functions
Authors: Fujita-Fujiharu Yoko , Hu Shangfan , Hirabayashi Ai , Takamatsu Yuki , Ng Yen Ni , Houri Kazuya , Muramoto Yukiko , Nakano Masahiro , Sugita Yukihiko , Noda Takeshi
Published: February 2024

The Ebola virus, a member of the Filoviridae family, causes severe hemorrhagic fever in humans. Filamentous virions contain a helical nucleocapsid responsible for genome transcription, replication, and packaging into progeny virions. The nucleocapsid consists of a helical nucleoprotein (NP)-viral genomic RNA complex forming the core structure, to which VP24 and VP35 bind externally. Two NPs, each paired with a VP24 molecule, constitute a repeating unit. However, the detailed nucleocapsid structure remains unclear. Here, we determined the nucleocapsid-like structure within virus-like particles at 4.6 Angstrom resolution using single-particle cryo-electron microscopy. Mutational analysis identified specific interactions between the two NPs and two VP24s and demonstrated that each of the two VP24s in different orientations distinctively regulates nucleocapsid assembly, viral RNA synthesis, and intracellular transport of the nucleocapsid. Our findings highlight the sophisticated mechanisms underlying the assembly and functional regulation of the nucleocapsid and provide insights into antiviral development.
Allele-level visualization of transcription and chromatin by high-throughput imaging
Authors: Almansour Faisal , Keikhosravi Adib , Pegoraro Gianluca , Misteli Tom
Published: February 2024

The spatial arrangement of the genome within the nucleus is a pivotal aspect of cellular organization and function with implications for gene expression and regulation. While all genome organization features, such as loops, domains, and radial positioning, are non-random, they are characterized by a high degree of single-cell variability. Imaging approaches are ideally suited to visualize, measure, and study single-cell heterogeneity in genome organization. Here, we describe two methods for the detection of DNA and RNA of individual gene alleles by fluorescence in situ hybridization (FISH) in a high-throughput format. We have optimized combined DNA/RNA FISH approaches either using simultaneous or sequential detection. These optimized DNA and RNA FISH protocols, implemented in a 384-well plate format alongside automated image and data analysis, enable accurate detection of chromatin loci and their gene expression status across a large cell population with allele-level resolution. We successfully visualized MYC and EGFR DNA and RNA in multiple cell types, and we determined the radial position of active and inactive MYC and EGFR alleles. These optimized DNA/RNA detection approaches are versatile and sensitive tools for mapping of chromatin features and gene activity at the single-allele level and at high throughput.
State-space trajectories and traveling waves following distraction
Authors: Batabyal Tamal , Brincat Scott L , Donoghue Jacob A. , Lundqvist Mikael , Mahnke Meredith K. , Miller Earl K
Published: February 2024

Cortical activity shows the ability to recover from distractions. We analyzed neural activity from the prefrontal cortex (PFC) of monkeys performing working memory tasks with mid-memory-delay distractions (a cued gaze shift or an irrelevant visual input). After distraction there were state-space rotational dynamics that returned spiking to population patterns similar to those pre-disruption. In fact, rotations were fuller when the task was performed correctly versus when errors were made. We found a correspondence between state-space rotations and traveling waves across the surface of the PFC. This suggests a role for emergent dynamics like state-space rotations and traveling waves in recovery from distractions.
Rydberg-atom-based single-photon detection for haloscope axion searches
Authors: Graham Eleanor , Ghosh Sumita , Zhu Yuqi , Bai Xiran , Cahn Sidney B. , Durcan Elsa , Jewell Michael J. , Speller Danielle H. , Zacarias Sabrina M. , Zhou Laura T. , Maruyama Reina H.
Published: February 2024

We propose a Rydberg-atom-based single-photon detector for signal readout in dark matter haloscope experiments between 40  μeV and 200  μeV (10 GHz and 50 GHz). At these frequencies, standard haloscope readout using linear amplifiers is limited by quantum measurement noise, which can be avoided by using a single-photon detector. Our single-photon detection scheme can offer scan rate enhancements up to a factor of 104 over traditional linear amplifier readout, and is compatible with many different haloscope cavities. We identify multiple haloscope designs that could use our Rydberg-atom-based single-photon detector to search for QCD axions with masses above 40  μeV (10 GHz), currently a minimally explored parameter space.

Published by the American Physical Society
2024
Standard model and the lattice
Authors: Creutz Michael
Published: February 2024

The SU(3)⊗SU(2)⊗U(1) standard model maps smoothly onto a conventional lattice gauge formulation, including the parity violation of the weak interactions. The formulation makes use of the pseudoreality of the weak group and requires the inclusion a full generation of both leptons and quarks. As in continuum discussions, chiral eigenstates of the Dirac operator generate known anomalies, although with rough gauge configurations these are no longer exact zero modes of the Dirac operator.

Published by the American Physical Society
2024
Dark photon effects with the kinetic and mass mixing in
Z
-boson decay processes
Authors: Sun Jin , Xing Zhi-Peng
Published: February 2024

Motivated by the most recent measurement of tau polarization in Z→τ+τ− by CMS, we have introduced a new U(1)X gauge boson field X, which can have renormalizable kinetic mixing with the standard model U(1)Y gauge boson field Y. In addition to the kinetic mixing of the dark photon, denoted as

σ

, there may also be mass mixing introduced by the additional Higgs doublet with a vacuum expectation value participating in U(1)X and electroweak symmetry breaking simultaneously. The interaction of the Z boson with the SM leptons is modified by the introduction of the mixing ratio parameter ε, which quantifies the magnitude of both the mass and kinetic mixing of the dark photon. Initially, we use the tau lepton as an example to explore the Z-boson phenomenology of the dark photon model with both kinetic and mass mixing. The goal is to determine the allowed parameter regions by taking into account constraints from the vector and axial-vector couplings gV,Aτ, the decay branching ratio Br(Z→τ−τ+) and tau-lepton polarization in Z→τ−τ+. We found that the mixing ratio plays important role in the Z-boson features by choosing different ε values. Furthermore, we aim to generalize our analysis from the tau-lepton case to include all fermions by conducting global fits. This allows us to identify viable regions by incorporating relevant fermion constraints and the W/Z mass ratio. Correspondingly, we obtain the fit results with the kinetic mixing parameter σ=0.074±0.021, mixing ratio ε=−1.37±0.46, and dark photon mass mX=275±39  GeV. Our global analysis indicates a preference for a dark photon mass larger than mZ.

Published by the American Physical Society
2024
Λb→Λc*
at
1/mc2
heavy quark mass order
Authors: Di Risi Vigilante , Iacobacci Davide , Sannino Francesco
Published: February 2024

We systematically compute the Λb(p,sb)→Λc(2595)+ and Λb(p,sb)→Λc(2625)+ form factors within the heavy quark effective theory (HQET) framework including O(1/mc2). Besides taking into account the Standard Model–like vector and axial contributions, we further determine tensor and pseudotensor form factors. Our work constitutes a step forward with respect to previous analyses allowing for a comprehensive study of the matrix element parametrization stemming from the HQET formalism. Finally, we demonstrate that the resulting form factors agree well with lattice quantum chromodynamics determinations stressing the need and relevance of the newly derived 1/mc2 corrections.

Published by the American Physical Society
2024
New observables for testing Bell inequalities in
W
boson pair production
Authors: Bi Qi , Cao Qing-Hong , Cheng Kun , Zhang Hao
Published: February 2024

We show that testing Bell inequalities in W± pair systems by measuring their angular correlation suffers from the ambiguity in kinetical reconstruction of the dilepton decay mode. We further propose a new set of Bell observables based on the measurement of the linear polarization of the W bosons that can be used in the semileptonic decay mode of W± pair, and we analyze the prospects of testing the violation of Bell inequalities at e+e− colliders.

Published by the American Physical Society
2024
Collective neutrino-antineutrino oscillations in dense neutrino environments?
Authors: Fiorillo Damiano F. G. , Raffelt Georg G. , Sigl Günter
Published: February 2024

The paradigm-changing possibility of collective neutrino-antineutrino oscillations was recently advanced in analogy to collective flavor oscillations. However, the amplitude for the backward scattering process νp1ν¯p2→νp2ν¯p1 is helicity suppressed and vanishes for massless neutrinos, implying that there is no off-diagonal refractive index between ν and ν¯ of a single flavor of massless neutrinos. For a nonvanishing mass, collective helicity oscillations are possible, representing de facto ν−ν¯ oscillations in the Majorana case. However, such phenomena are suppressed by the smallness of neutrino masses as discussed in the previous literature.

Published by the American Physical Society
2024
Optimum filter-based analysis for the characterization of a high-resolution magnetic microcalorimeter
Authors: Toschi Francesco , Maier Benedikt , Heine Greta , Ferber Torben , Kempf Sebastian , Klute Markus , von Krosigk Belina
Published: February 2024

Ultrasensitive cryogenic calorimeters have become a favored technology with widespread application where eV-scale energy resolutions are needed. In this article, we characterize the performance of an x-ray magnetic microcalorimeter (MMC) using a Fe55 source. Employing an optimum filter-based amplitude estimation and energy reconstruction, we demonstrate that a full-width half-maximum (FWHM) resolution of ΔEFWHM=(1.25±0.17(stat)−0.07+0.05(syst))  eV can be achieved, leading to an unprecedented energy resolving power E/ΔEFWHM∼4700 among existing energy-dispersive detectors for soft and tender x-rays. We also derive the best possible resolution and discuss limiting factors affecting the measurement. The analysis pipeline for the MMC data developed in this paper is furthermore an important step for the realization of the proposed superfluid helium-based experiment DELight, which will search for direct interaction of dark matter particles with masses below 100  MeV/c2.

Published by the American Physical Society
2024
Stability and causality criteria in linear mode analysis: Stability means causality
Authors: Wang Dong-Lin , Pu Shi
Published: February 2024

Causality and stability are fundamental requirements for the differential equations describing predictable relativistic many-body systems. In this work, we investigate the stability and causality criteria in linear mode analysis. We discuss the updated stability criterion in 3+1-dimensional systems and introduce the improved sufficient criterion for causality. Our findings clearly demonstrate that stability implies causality in linear mode analysis. Furthermore, based on the theorems present in this work, we conclude that if updated stability criterion and improved causality criterion are fulfilled in one inertial frame of reference (IFR), they hold for all IFR.

Published by the American Physical Society
2024
Tidal effects and renormalization at fourth post-Minkowskian order
Authors: Jakobsen Gustav Uhre , Mogull Gustav , Plefka Jan , Sauer Benjamin
Published: February 2024

We determine the adiabatic tidal contributions to the radiation reacted momentum impulse Δpiμ and scattering angle θ between two scattered massive bodies (neutron stars) at next-to-next-to-leading post-Minkowskian order. The state-of-the-art three-loop (fourth post-Mikowskian order) worldline quantum field theory toolkit using dimensional regularization is employed to establish the classical observables. We encounter divergent terms in the gravitoelectric and gravitomagnetic quadrupolar sectors necessitating the addition of postadiabatic counterterms in this classical theory. This leads us to include also the leading postadiabatic tidal contributions to the observables. The resulting renormalization group flow of the associated postadiabatic Love numbers is established and shown to agree with a recent gravitoelectric third post-Newtonian analysis in the nonrelativistic limit.

Published by the American Physical Society
2024
When an active bath behaves as an equilibrium one
Authors: Khali Shubhendu Shekhar , Peruani Fernando , Chaudhuri Debasish
Published: February 2024

Active scalar baths consisting of active Brownian particles are characterized by a non-Gaussian velocity distribution, a kinetic temperature, and a diffusion coefficient that scale with the square of the active velocity v0. While these results hold in overdamped active systems, inertial effects lead to normal velocity distributions, with kinetic temperature and diffusion coefficient increasing as ∼v0α with 1<α<2. Remarkably, the late-time diffusivity and mobility decrease with mass. Moreover, we show that the equilibrium Einstein relation is asymptotically recovered with inertia. In summary, the inertial mass restores an equilibriumlike behavior.

Published by the American Physical Society
2024
Footprints of the QCD Crossover on Cosmological Gravitational Waves at Pulsar Timing Arrays
Authors: Franciolini Gabriele , Racco Davide , Rompineve Fabrizio
Published: February 2024

Pulsar timing arrays (PTAs) have reported evidence for a stochastic gravitational wave (GW) background at nanohertz frequencies, possibly originating in the early Universe. We show that the spectral shape of the low-frequency (causality) tail of GW signals sourced at temperatures around T≳1  GeV is distinctively affected by confinement of strong interactions (QCD), due to the corresponding sharp decrease in the number of relativistic species, and significantly deviates from ∼f3 commonly adopted in the literature. Bayesian analyses in the NANOGrav 15 years and the previous international PTA datasets reveal a significant improvement in the fit with respect to cubic power-law spectra, previously employed for the causality tail. While no conclusion on the nature of the signal can be drawn at the moment, our results show that the inclusion of standard model effects on cosmological GWs can have a decisive impact on model selection.

Published by the American Physical Society
2024
Inferring attracting basins of power system with machine learning
Authors: Du Yao , Li Qing , Fan Huawei , Zhan Meng , Xiao Jinghua , Wang Xingang
Published: February 2024

Power systems dominated by renewable energy encounter frequently large, random disturbances, and a critical challenge faced in power-system management is how to anticipate accurately whether the perturbed systems will return to the functional state after the transient or collapse. Whereas model-based studies show that the key to addressing the challenge lies in the attracting basins of the functional and dysfunctional states in the phase space, the finding of the attracting basins for realistic power systems remains a challenge, as accurate models describing the system dynamics are generally unavailable. Here we propose a new machine-learning technique, namely balanced reservoir computing, to infer the attracting basins of a typical power system based on measured data. Specifically, trained by the time series of a handful of perturbation events, we demonstrate that the trained machine can predict accurately whether the system will return to the functional state in response to a large, random perturbation, thereby reconstructing the attracting basin of the functional state. The working mechanism of the new machine is analyzed, and it is revealed that the success of the new machine is attributed to the new objective function adopted in optimizing the machine hyperparameters, which keeps a good balance between the echo and fading properties of the reservoir network; the effect of noisy signals on the prediction performance is also investigated, and it is found that the machine performance is improved by introducing a certain amount of noise. Finally, we demonstrate that the new technique can also be utilized to infer the attracting basins of coexisting attractors in typical chaotic systems.

Published by the American Physical Society
2024
Analog Simulation of High-Harmonic Generation in Atoms
Authors: Argüello-Luengo Javier , Rivera-Dean Javier , Stammer Philipp , Maxwell Andrew S. , Weld David M. , Ciappina Marcelo F. , Lewenstein Maciej
Published: February 2024

The demanding experimental access to the ultrafast dynamics of materials challenges our understanding of their electronic response to applied strong laser fields. For this purpose, trapped ultracold atoms with highly controllable potentials have become an enabling tool to describe phenomena in a scenario in which some effects are more easily accessible and 12 orders of magnitude slower. In this work, we introduce a mapping between the parameters of attoscience platforms and atomic cloud simulators and propose an experimental protocol to access the emission spectrum of high-harmonic generation, a regime that has so far been elusive to cold-atom simulation. As we illustrate, the benchmark offered by these simulators can provide new insights into the conversion efficiency of extended and short nuclear potentials, as well as the response to applied elliptical polarized fields or ultrashort few-cycle pulses.

Published by the American Physical Society
2024
Persistence of atoms in molecules: there is room beyond electron densities
Authors: Menéndez-Herrero María , Martín Pendás Ángel
Published: February 2024

Evidence that the electronic structure of atoms persists in molecules to a much greater extent than has been usually admitted is presented. This is achieved by resorting to N-electron real-space descriptors instead of one- or at most two-particle projections like the electron or exchange-correlation densities. Here, the 3N-dimensional maxima of the square of the wavefunction, the so-called Born maxima, are used. Since this technique is relatively unknown to the crystallographic community, a case-based approach is taken, revisiting first the Born maxima of atoms in their ground state and then some of their excited states. It is shown how they survive in molecules and that, beyond any doubt, the distribution of electrons around an atom in a molecule can be recognized as that of its isolated, in many cases excited, counterpart, relating this fact with the concept of energetic promotion. Several other cases that exemplify the applicability of the technique to solve chemical bonding conflicts and to introduce predictability in real-space analyses are also examined.
Crystal structures of sulfonamide protected bicyclic guanidines: (S)-8-{[(tert-butyldimethylsilyl)oxy]methyl}-1-[(2,2,4,6,7-pentamethyl-2,3-dihydrobenzofuran-5-yl)sulfonyl]-1,3,4,6,7,8-hexahydro-2H-pyrimido[1,2-a]pyrimidin-1-ium trifluoromethanesulfonate and (S)-8-(iodomethyl)-1-tosyl-1,3,4,6,7,8-hexahydro-2H-pyrimido[1,2-a]pyrimidin-1-ium iodide
Authors: Alaboosh Jamal M. H. , Hill Steven P. , Kariuki Benson M. , Redman James E.
Published: February 2024

Two compounds, (S)-8-{[(tert-butyldimethylsilyl)oxy]methyl}-1-[(2,2,4,6,7-pentamethyl-2,3-dihydrobenzofuran-5-yl)sulfonyl]-1,3,4,6,7,8-hexahydro-2H-pyrimido[1,2-a]pyrimidin-1-ium trifluoromethanesulfonate, C27H46N3O4SSi+·CF3O3S−, (1) and (S)-8-(iodomethyl)-1-tosyl-1,3,4,6,7,8-hexahydro-2H-pyrimido[1,2-a]pyrimidin-1-ium iodide, C15H21IN3O2S+·I−, (2), have been synthesized and characterized. They are bicyclic guanidinium salts and were synthesized from N-(tert-butoxycarbonyl)-L-methionine (Boc-L-Met-OH). The guanidine is protected by a 2,2,4,6,7-pentamethyldihydrobenzofuran-5-sulfonyl (Pbf, 1) or a tosyl (2) group. In the crystals of both compounds, the guanidinium group is almost planar and the N–H forms an intramolecular hydrogen bond in a six-membered ring to the oxygen atom of the sulfonamide protecting group.
Crystal structure and Hirshfeld surface analysis of 3-phenyl-1-{3-[(3-phenylquinoxalin-2-yl)oxy]propyl}-1,2-dihydroquinoxalin-2-one
Authors: Abad Nadeem , Mague Joel T. , Alsubari Abdulsalam , Essassi El Mokhtar , Alzahrani Abdullah Yahya Abdullah , Ramli Youssef
Published: February 2024

In the title compound, C31H24N4O2, the quinoxaline units are distinctly non-planar and twisted end-to-end. In the crystal, C—H...O and C—H...N hydrogen bonds link the molecules into chains extending along the a-axis direction. The chains are linked through π-stacking interactions between inversion-related quinoxaline moieties.
Helicopter airfoil aerodynamic characteristics and rotor trim in sandy environments
Authors: Huang Zejian , Cao Yihua , Wang Yanyang
Published: February 2024

Purpose

The sandy environment is one of the typical environments in which helicopters operate. Air-sand two-phase flow in sandy environments may be an important factor affecting flight safety. Taking a typical example, this paper aims to investigate the aerodynamic and rotor trim characteristics of the UH-60 helicopter in sandy environments.

Design/methodology/approach

A computational study is conducted to simulate the air-sand flow over airfoils based on the Euler–Lagrange framework. The simulation uses the S-A turbulence model and the two-way momentum coupling methodology. Additionally, the trim characteristics of the UH-60 rotor are calculated based on the isolated rotor trim algorithm.

Findings

The simulation results show that air-sand flow significantly affects the aerodynamic characteristics of the SC1095 airfoil and the SC1094R8 airfoil. The presence of sand particles leads to a decrease in lift and an increase in drag. The calculation results of the UH-60 helicopter rotor indicate that the thrust decreases and the torque increases in the sandy environment. To maintain a steady forward flight in sandy environments, it is necessary to increase the collective pitch and the longitudinal cyclic pitch.

Originality/value

In this paper, the aerodynamic characteristics of airfoils and the trim characteristics in the air-sand flow of the UH-60 helicopter are discussed, which might be a new view to analyse the impact of sandy environments on helicopter safety and manoeuvring.
Impact of self-efficacy on construction labor productivity: the mediating role of work motivation
Authors: Van Tam Nguyen
Published: February 2024

Purpose

Though widely recognized as essential for improving work performance across various domains, self-efficacy’s specific role in managing construction workforces remains understudied. This knowledge gap restricts our ability to uncover new factors that enhance workforce management effectiveness and ultimately boost construction labor productivity (CLP). To address this, our study proposes and tests a novel model. This model explores the impact mechanism of self-efficacy on CLP by investigating the mediating role of work motivation. By delving into this crucial yet underexplored area, we aim to provide valuable insights for construction project managers and researchers alike, paving the way for more effective workforce management strategies and consequently, improved CLP.

Design/methodology/approach

This study utilizes a mixed-method approach, incorporating both qualitative and quantitative methodologies. Data from 112 rebar workers at five construction sites in Vietnam underwent analysis using Cronbach’s alpha, exploratory factor analysis (EFA), confirmatory factor analysis (CFA) and structural equation modeling (SEM) to examine the novel research model.

Findings

The results indicate a positive and significant association between self-efficacy and CLP. Additionally, work motivation emerged as a full mediator in the relationship between self-efficacy and CLP. Specifically, individuals with higher self-efficacy set ambitious goals and invest more effort in their pursuit, leading to increased work motivation and, ultimately, heightened productivity levels.

Practical implications

The significant implications of the current study extend to construction managers and policymakers alike. Construction managers can leverage the findings to devise targeted interventions aimed at enhancing the self-efficacy and work motivation of their workforce, potentially resulting in noteworthy enhancements in CLP. Policymakers, too, can benefit from these findings by formulating policies that actively support the cultivation of self-efficacy and work motivation among construction workers. Such policies have the potential to foster a more productive and efficient construction industry, aligning with the broader goals of workforce development and industry enhancement.

Originality/value

This study expands existing knowledge by identifying the important role of self-efficacy in work performance enhancement and the mediating role of work motivation in terms of these relationships.
Assessing the drivers to share the content on social media in tourism: the empirical evidence on a world heritage city
Authors: García-Haro María Ángeles , Ruiz-Palomino Pablo , Martínez-Cañas Ricardo , Martínez-Ruiz María Pilar
Published: February 2024

Purpose

This study seeks to provide a greater understanding of the variables that influence travellers’ intention to participate in social media, paying special attention to (1) the direct impact of perceived usefulness (PU) of social media and (2) the moderating impact of tourists’ altruism and self-interest.

Design/methodology/approach

The proposed conceptual model was empirically tested using an online questionnaire distributed to a sample of 394 tourists visiting a World Heritage city.

Findings

The findings show that perceived social media usefulness has a significant effect on users’ intention to share experiences. Additionally, self-interest appears to moderate the relationship between perceived social media usefulness and users’ sharing intention, but the results do not support the moderating effect of altruism.

Originality/value

Despite scholars’ growing interest in social networks as sources of tourist information, little is known about the aspects that encourage users’ participation in these platforms. This paper offers key contributions to the relevant literature in this field and offers compelling recommendations for tour operators' management of social networks.
Optimal bidding strategy for integrated CHP system by modified heuristic algorithm considering CO2 emission in energy and reserve markets
Authors: Nazari Mohammad Esmaeil , Assari Zahra
Published: February 2024

Purpose

This study aims to solve optimal pricing and power bidding strategy problem for integrated combined heat and power (CHP) system by using a modified heuristic optimization algorithm.

Design/methodology/approach

In electricity markets, generation companies compete according to their bidding parameters; therefore, optimal pricing and bidding strategy are solved. Recently, CHP units are significantly operated by generation companies to meet power and heat, simultaneously.

Findings

For validation, it is shown that profit is improved by 0.04%–48.02% for single and 0.02%–31.30% for double-sided auctions. As heat price curve is extracted, the simulation results show that when CHP system is integrated with other units results in profit increase and emission decrease by 3.04%–3.18% and 2.23%–4.13%, respectively. Also, CHP units significantly affect bidding parameters.

Originality/value

The novelties are pricing and bidding strategy of integrated CHP system is solved; local heat selling is considered in pricing and bidding strategy problem and heat price curve is extracted; the effects of CHP utilization on bidding parameters are investigated; a modified heuristic and deterministic optimization algorithm is presented.
Assessing the nonlinear impact of economic growth and renewable energy consumption on CO2 emissions in India: recent evidence from smooth transition autoregression model
Authors: Ganie Anam Ul Haq , Ahmad Masroor
Published: February 2024

Purpose

The purpose of this study is to investigate the nonlinear effects of renewable energy (RE) consumption and economic growth on per capita CO2 emissions during the time span from 1980 to 2020.

Design/methodology/approach

The study uses the logistic smooth transition autoregression (STAR) model to decipher the nonlinear relationship between RE consumption, economic growth and CO2 emissions in the Indian economy.

Findings

The estimated results confirm a nonlinear relationship between India’s economic growth, RE consumption and CO2 emissions. The authors found that economic growth positively impacts CO2 emissions until it reaches a specific threshold of 1.81 (per capita growth). Beyond this point, further economic growth leads to a reduction in CO2 emissions. Similarly, RE consumption positively affects CO2 emissions until economic growth reaches the same threshold level, after which an increase in RE consumption negatively impacts CO2 emissions.

Research limitations/implications

The study suggests that India should optimize the balance between economic growth and RE consumption to mitigate CO2 emissions. Policymakers should prioritize the adoption of RE during the early stages of economic growth. As economic growth reaches the specific threshold of 1.81 per capita, the economy should shift to more sustainable and energy-efficient practices to limit the effect of further CO2 emissions on further economic growth.

Originality/value

To the best of the authors’ knowledge, this study represents the first-ever endeavor to reexamine the nonlinear relationship between RE consumption, economic growth and CO2 emissions in India, using the STAR model.