bluuebunny/crossref_metadata_2025 huggingface dataset:
Is increasing the effective leg length of a human runner metabolically beneficial?
Authors: Bertschy Montgomery , Lino Herlandt , Healey Laura , Hoogkamer Wouter
Published: January 2025

The purpose of this study was to understand if footwear midsole thickness can decrease the metabolic cost of running by increasing the effective leg length of a runner. We also sought to understand the role of midsole compliance on these measures.

Participants (n = 16) ran on a treadmill at 14 km h-1in four mass-matched shoe conditions: 30, 40, and 60 mm thickness of a firm midsole foam and 60 mm thickness of a compliant midsole foam. Over two testing sessions, we measured metabolic cost (two 5-minute trials in each condition) and biomechanical measures (one 2-minute trial in each condition).

Increasing thickness in the firm midsole conditions increased effective leg length during early, mid, and late stance (all p < 0.001). However, metabolic cost increased (p = 0.031). Changing material from firm to compliant decreased effective leg length during midstance (p < 0.001), but not during early or late stance, and decreased metabolic cost (p < 0.001).

Results suggest that increasing midsole thickness can increase the effective leg length of a runner, but this isolated effect leads to increasing in metabolic cost. On the other hand, increasing midsole compliance leads to reductions in metabolic cost, agreeing with previous literature.

We suggest that the performance benefits seen in advanced footwear technology with increased midsole thickness are likely due to increased capacity to return mechanical energy, not due increases in effective leg length.

Summary Statement

Increased midsole compliance, not increased effective leg length, is responsible for decreased metabolic cost in running.
Highly efficient organ-targeting transport through the ventral midline interstitial channels injection: a new development of interstitium
Authors: Song Xiaojing , Gu Xin , Xiong Feng , Jia Shuyong , Wang Shuyou , Wang Guangjun , Wang Yanpin , Zhang Weibo
Published: January 2025

How to improve the drugs bioavailability has always been a hot and difficult topic. Conventional drug delivery methods, such as oral administration and the blood circulation system, suffer from issues such as low targeting efficiency, low bioavailability, and high side effects. Recently, interstitium has gradually been recognized as an important new organ. Interstitial injection allows small molecules to move through interstitial channels with interstitial fluid flow and be transported to organs, providing new possibilities for drug delivery. In this study, using fluorescein sodium as a drug model, we systematically investigated the distribution of the fluorescein sodium in organs and body surface of the rats after ventral midline interstitial channels injection. In addition, we observed the microstructure of the ventral midline interstitial channels of abdominal wall and the effects of channels ligation on fluorescein sodium delivery and target organs, to explore the mechanism of interstitial injection. We found that fluorescein sodium can be efficiently transported to the uterus and ovaries along the ventral midline interstitial channels, and the parallel fibers and interconnected interstitial spaces of the channels facilitate long-distance transport of solutes. Additionally, the blockage of the transmission through those channels had results in a significant decrease in targeted transport efficiency over long distances, a decrease in oestrogen levels, organ coefficients, and body weights in female rats. Therefore, the ventral midline interstitial channels with free fluid flow may be a potential communication pathway between body surface and organs. These findings have significant value in the development of drug delivery.
Small Hands, Big Ideas: Exploring Nurturing Care Through Beatrice Alemagna’s “What is a Child?”
Authors: Ravaldi Claudia , Vannacci Alfredo
Published: January 2025

This study examines the use of Beatrice Alemagna’s picture book "What is a Child?" as a tool for understanding and implementing nurturing care principles in perinatal healthcare settings. Through mixed-methods analysis of forum discussions among 42 perinatal professionals, including psychologists, midwives, physicians, nurses, pharmacists and early childhood educators, we explored how engagement with the book’s metaphorical and visual elements facilitated professional reflection and development. Qualitative analysis revealed four primary themes: the power of metaphors in conveying complex caregiving concepts, the importance of collective care and community support, understanding the temporality of care, and fostering transformative dialogue. Quantitative analysis demonstrated significant differences in thematic engagement across professional groups, with medical professionals emphasizing physical health (20.8%) and nutrition (32.1%), while psychologists focused more on early learning opportunities (28.3%) and responsive caregiving (21.0%). However, the picture book’s narrative framework encouraged professionals to transcend their domain-specific perspectives, fostering a more holistic appreciation of nurturing care principles. These findings suggest that carefully selected picture books can serve as sophisticated tools for professional development in perinatal care, particularly in translating abstract theoretical concepts into actionable insights while honoring different professional perspectives and expertise.
Understanding the United States Black-White Life Expectancy Gap, 2007-2018
Authors: Wetzler Harry
Published: January 2025

Background

Life expectancy is a critical measure of population health. In the U.S., Black Americans have historically experienced lower life expectancy than White Americans due to factors such as health insurance inequities, socioeconomic disparities, and systemic barriers. Though the Black-White life expectancy gap narrowed after 1990, it has fluctuated in recent years, influenced by socioeconomic changes and the COVID-19 pandemic.

Objective

This study examines how national-level differences in education and income contributed to the Black-White life expectancy gap in the United States from 2007 to 2018.

Methods

Data were analyzed from the National Health and Nutrition Examination Survey (2007–2018) and its Linked Mortality File. Using 3 survival models, this study assessed life expectancy at age 20 for Non-Hispanic Black (NHB) and Non-Hispanic White (NHW) populations. Covariates included education and income.

Results

The unadjusted life expectancy gap at age 20 between NHB and NHW individuals averaged 3 years. Adjusting for education using a flexible parametric survival model reduced the gap by 50%, while adjusting for income reduced the gap by 75%. When both factors were adjusted simultaneously, two survival models indicated that NHB life expectancy slightly exceeded NHW life expectancy. Income disparities persisted across educational levels, signifying unequal economic returns to education.

Conclusions

Addressing income disparities is essential for reducing racial inequities in life expectancy. Policies promoting both equitable education access and income equivalence are critical for achieving health equity and improving population health.
Transcriptional responses to prolonged oxidative stress require cholinergic activation of G-protein-coupled receptor signaling
Authors: Biswas Kasturi , Moore Caroline , Rogers Hannah , Wani Khursheed A , Pukkila-Worley Read , Higgins Daniel P , Walker Amy K , Rand James B , Francis Michael M
Published: January 2025

Organisms have evolved protective strategies that are geared toward limiting cellular damage and enhancing organismal survival in the face of environmental stresses, but how these protective mechanisms are coordinated remains unclear. Here, we define a requirement for neural activity in mobilizing the antioxidant defenses of the nematodeCaenorhabditis elegansboth during prolonged oxidative stress and prior to its onset. We show that acetylcholine-deficient mutants are particularly vulnerable to prolonged oxidative stress. We find that prolonged oxidative stress mobilizes a broad transcriptional response which is strongly dependent on both cholinergic signaling and activation of the muscarinic G-protein acetylcholine coupled receptor (mAChR) GAR-3. Gene enrichment analysis revealed a lack of upregulation of proteasomal proteolysis machinery in both cholinergic-deficient andgar-3mAChR mutants, suggesting that muscarinic activation is critical for stress-responsive upregulation of protein degradation pathways. Further, we find that GAR-3 overexpression in cholinergic motor neurons prolongs survival during prolonged oxidative stress. Our studies demonstrate neuronal modulation of antioxidant defenses through cholinergic activation of G protein-coupled receptor signaling pathways, defining new potential links between cholinergic signaling, oxidative damage, and neurodegenerative disease.
FAXC and Metaxin Proteins of Fungi and Bacteria: Distinct Categories of Proteins with Shared Structural Features
Authors: Adolph Kenneth W.
Published: January 2025

FAXC (failed axon connections) proteins are shown to be present in fungi and bacteria and to have structural homology to metaxin proteins of vertebrates and invertebrates. Fungal and bacterial FAXC proteins also share structural features with the metaxin-like proteins of plants and protists. But the FAXC and metaxin proteins are different categories of proteins, as seen in the low percentages of identical amino acids in pairwise sequence alignments. The metaxin-like structural features include the conserved protein domains that are characteristic of metaxin proteins. These are the GST_N_Metaxin, GST_C_Metaxin, and Tom37 domains. Another metaxin-like structural feature is a conserved pattern of α-helical and β-strand secondary structure. The FAXC proteins of both fungi and bacteria share this pattern of secondary structure with vertebrate and invertebrate metaxin proteins. The predicted 3D structures of fungal and bacterial FAXC proteins revealed a characteristic 4-stranded, β-sheet motif that was also found to characterize metaxin proteins. Phylogenetic analysis demonstrated that fungal and bacterial FAXC proteins are related by evolution to vertebrate metaxin proteins, though more closely related to vertebrate FAXC proteins. The neighboring genes of the FAXC genes of fungi are different than the neighboring genes of vertebrate FAXC and metaxin genes. A high level of protein sequence homology was found for the multiple predicted FAXC proteins of fungi that have multiple FAXC genes, and in comparing the FAXC proteins of different species of bacteria of the same genus.
Rhythms of Early Life: Gut Microbiota Rhythmicity and Circadian Maturation in infants
Authors: Mühlematter Christophe , Nielsen Dennis S. , Castro-Mejía Josue L. , Walser Jean-Claude , Schoch Sarah F. , Kurth Salome
Published: January 2025

Background

The human gut microbiota undergoes daily fluctuations, yet its interaction with sleep-wake patterns during infancy remains largely uncharted. This study aims to elucidate the relationship between gut microbiota rhythmicity and the development of sleep patterns in infants over the first year of life. We continuously monitored 162 healthy infants across multiple days at 3, 6, and 12 months of age using ankle actigraphy and 24-hour diaries. The Circadian Function Index (CFI) was computed as a proxy for sleep-wake rhythm maturation. Stool samples were collected to profile gut microbiota composition via 16S rRNA gene amplicon sequencing, and microbial oscillations were assessed through sine and cosine fitting to detect 24-hour patterns.

Results

Our findings revealed that the abundance of bacterial taxa exhibited rhythmic patterns, with 26 zOTUs (1.74%) following a sine pattern and 100 zOTUs (6.69%) displaying cosine rhythmicity. Cosine rhythmicity became more pronounced with age, showing strong maturation: 7 zOTUs at 3 months, 2 zOTUs at 6 months, and 86 zOTUs at 12 months. Notably, 105 zOTUs (7.02%) were associated with CFI, demonstrating a significant relationship between gut microbiota rhythms and sleep development. Among these, 27 zOTUs with sine dynamics and 96 zOTUs with cosine dynamics were linked to CFI, with this association strengthening as infants aged.

Conclusions

These results highlight the increasing synchronization between gut microbiota rhythmicity and sleep-wake cycles during infancy, pointing to a critical window for potential health interventions. This novel observation, previously reported in rodents and adults, underscores the role of gut microbiota in early human development, offering new avenues for enhancing developmental outcomes through targeted interventions.
Mirror effect of genomic deletions and duplications on cognitive ability across the human cerebral cortex
Authors: Kumar Kuldeep , Kazem Sayeh , Huguet Guillaume , Renne Thomas , Engchuan Worrawat , Jean-Louis Martineau , Kopal Jakub , Saci Zohra , Thiruvahindrapuram Bhooma , MacDonald Jeffrey R. , Mollon Josephine , Schultz Laura M. , Knowles Emma E.M. , Porteous David , Davies Gail , Redmond Paul , Harris Sarah E. , Cox Simon R. , Schumann Gunter , Pausova Zdenka , Greenwood Celia M. T. , Paus Tomas , Scherer Stephen W. , Almasy Laura , Sebat Jonathan , Glahn David , Dumas Guillaume , Jacquemont Sebastien
Published: January 2025

Regulation of gene expression shapes the interaction between brain networks which in turn supports psychological processes such as cognitive ability. How changes in the level of gene expression across the cerebral cortex influence cognitive ability remains unknown. Here, we tackle this by leveraging genomic deletions and duplications - copy number variants (CNVs) that fully encompass one or more genes expressed in the human cortex - which lead to large effects on gene expression levels. We assigned genes to 180 regions of the human cerebral cortex based on their preferential expression across the cortex computed using data from the Allen Human Brain Atlas. We aggregated CNVs in cortical regions, and ran a burden association analysis to compute the mean effect size of genes on general cognitive ability for each of the 180 regions. When affected by CNVs, most of the regional gene-sets were associated with lower cognitive ability. The spatial patterns of effect sizes across the cortex were correlated negatively between deletions and duplications. The largest effect sizes for deletions and duplications were observed for gene-sets with high expression in sensorimotor and association regions, respectively. These two opposing patterns of effect sizes were not influenced by intolerance to loss of function, demonstrating orthogonality to dosage-sensitivity scores. The same mirror patterns were also observed after stratifying genes based on cell types and developmental epoch markers. These results suggest that the effect size of gene dosage on cognitive ability follows a cortical gradient. The same brain region and corresponding gene set may show different effects on cognition depending on whether variants increase or decrease transcription. The latter has major implications for the association of brain networks with phenotypes.
Regulation of eye movements and pupil size in natural scenes
Authors: Hahn Alexander , Brielmann Aenne , Tabandeh Niloufar , Spitschan Manuel
Published: January 2025

The visual diet of humans is complex in space, time, spectrum, and consequently the activation of the retinal photoreceptors. While analyses of natural scenes have yielded valuable insights, the naturalistic natural stimulus on the retina is not very well understood. In the present study, we performed eye tracking in naturalistic indoor and outdoor real-world scenes. We recorded pupil size, several saccade and fixation metrics, as well as subjective scene perception ratings derived from subjective questionnaires. For the first five seconds of eye tracking, the descriptive data analysis revealed significantly increased average saccade frequency (p =.0025), amplitude (p =.0049), peak velocity (p =.0072), as well as pupil size (p = 1.307e-09) in the indoor environments. After this initial phase, these differences vanished, except for pupil size. Using an exploratory analysis on the whole 4-minute measurement, we found that saccade and fixation metrics, along with scene ratings, showed significantly different correlations between indoor and outdoor conditions. Despite the inherent constraints of such a naturalistic study (reduced ability to exert control over the precise task and the environmental conditions), we contend that the dataset holds substantial value for the field of eye movement research, as it has effectively minimized confounding factors that have been prevalent in previous eye tracking studies.
Securin and cyclin B1-CDK1, but not SGO2, regulate separase activity during meiosis I in mouse oocytes
Authors: Wetherall Benjamin , Bulmer David , Sarginson Alexandra , Thomas Christopher , Madgwick Suzanne
Published: January 2025

During meiosis I in oocytes, anaphase is triggered by deactivation of cyclin B1-CDK1 and activation of separase. Active separase plays an essential role in cleaving cohesin rings that hold homologous chromosomes together. Critically, separase must be inhibited until all chromosomes are aligned and the cell is prepared for anaphase I. Inhibition can be mediated through the binding of separase to either securin or cyclin B1-CDK1. The relative contribution of each inhibitory pathway varies depending on cell type. Recently, shugoshin-2 (SGO2) has also been shown to inhibit separase in mitotic cells. Here, we used a separase biosensor and perturbed the three inhibitory pathways during meiosis I in mouse oocytes. We show that inhibition mediated by either securin or cyclin B1-CDK1, but not SGO2, is independently sufficient to suppress separase activity. However, when both the securin and cyclin B1-CDK1 inhibitory pathways are perturbed together, separase activity begins prematurely, resulting in gross segregation defects. Furthermore, we characterised shugoshin-2 destruction dynamics and conclude that it is not an essential separase inhibitor in mouse oocytes. The existence of multiple separase inhibitory pathways highlights the critical importance of tightly regulated separase activity during this unique and challenging cell division.
Complex roles for proliferating cell nuclear antigen in human cytomegalovirus replication
Authors: Longmire Pierce , Daigle Olivia , Zeltzer Sebastian , Lee Matias , Svoboda Marek , Padilla-Rodriguez Marco , Bobak Carly , Bosco Giovanni , Goodrum Felicia
Published: January 2025

DNA viruses at once elicit and commandeer host pathways, including DNA repair pathways for virus replication. Despite encoding its own DNA polymerase and processivity factor, human cytomegalovirus (HCMV) recruits the cellular processivity factor, proliferating cell nuclear antigen (PCNA) and specialized host DNA polymerases involved in translesion synthesis (TLS) to replication compartments (RCs) where viral DNA (vDNA) is synthesized. While the recruitment of TLS polymerases is important for viral genome stability, the role of PCNA is poorly understood. PCNA function in DNA repair is regulated by monoubiquitination (mUb) or SUMOylation of PCNA at lysine 164 (K164). We find that mUb-PCNA increases over the course of infection, and modification of K164 is required for PCNA-mediated restriction of virus replication. mUb-PCNA plays important known roles in recruiting TLS polymerases to DNA, which we have shown are important for viral genome integrity and diversity, represented by novel junctions and single nucleotide variants (SNVs), respectively. We find that PCNA drives SNVs on vDNA similar to Y-family TLS polymerases, but that this did not require modification at K164. Unlike TLS polymerases, PCNA was dispensable for preventing large scale rearrangements on vDNA. These striking results suggest separable PCNA-dependent and -independent functions of TLS polymerases on vDNA. By extension, these results imply roles for TLS polymerase beyond their canonical function in TLS in host biology. These findings highlight PCNA as a complex restriction factor for HCMV infection, likely with multiple distinct roles, and provides new insights into the PCNA-mediated regulation of DNA synthesis and repair in viral infection.
Topography of scene memory and perception activity in posterior cortex – a publicly available resource
Authors: Steel Adam , Prasad Deepa , Garcia Brenda D. , Robertson Caroline E.
Published: January 2025

Adaptive behavior in complex environments requires integrating visual perception with memory of our spatial environment. Recent work has implicated three brain areas in posterior cerebral cortex — the place memory areas (PMAs) that are anterior to the three visual scene perception areas (SPAs) – in this function. However, PMAs’ relationship to the broader cortical hierarchy remains unclear due to limited group-level characterization. Here, we examined the PMA and SPA locations across three fMRI datasets (44 participants, 29 female). SPAs were identified using a standard visual localizer where participants viewed scenes versus faces. PMAs were identified by contrasting activity when participants recalled personally familiar places versus familiar faces (Datasets 1-2) or places versus multiple categories (familiar faces, bodies, and objects, and famous faces; Dataset 3). Across datasets, the PMAs were located anterior to the SPAs on the ventral and lateral cortical surfaces. The anterior displacement between PMAs and SPAs was highly reproducible. Compared to public atlases, the PMAs fell at the boundary between externally-oriented networks (dorsal attention) and internally-oriented networks (default mode). Additionally, while SPAs overlapped with retinotopic maps, the PMAs were consistently located anterior to mapped visual cortex. These results establish the anatomical position of the PMAs at inflection points along the cortical hierarchy between unimodal sensory and transmodal, apical regions, which informs broader theories of how the brain integrates perception and memory for scenes. We have released probabilistic parcels of these regions to facilitate future research into their roles in spatial cognition.

Significance statement

Complex behavior requires the dynamic interplay between mnemonic and perceptual information. For example, navigation requires representation of the current visual scene and its relationship to the surrounding visuospatial context. We have suggested that the place memory areas, three brain areas located anterior to the scene perception areas in visual cortex, are well-positioned to serve this role. Here, in a large group of participants, we show that the place memory areas are robustly localizable, and that their position at the interface of multiple distributed brain networks is uniquely suited to mnemonic-perceptual integration. We have released probabilistic regions-of-interest and localization procedure so that others can identify these areas in their own participants.
Engineering surface electrostatics affords control over morphological preference, synergy, and activity in polymer degrading enzymes
Authors: Oliveira Liliana , Rudge Elaine M. , Zahn Michael , Bemmer Victoria , Green Kerry R. , Pickford Andrew R. , Lichtenstein Bruce R.
Published: January 2025

The biocatalytic recycling of plastics, such as polyethylene terephthalate (PET), promises a sustainable alternative to our present open-loop cycles. Engineering of PET-hydrolases for this purpose has focused on improving activity near the glass-transition temperature of the polymer by increasing their thermostability, neglecting other features of the protein-polymer system that affect enzymatic activity. Here, we isolate the effect of electrostatics on the activity of a thermophilic PETase by rationally redesigning its surface charge, while preserving its thermodynamic properties. The enzyme variant,SfInv, shows orders of magnitude improvements in binding affinity and in activity towards untreated plastic films, with inverted morphological preference. When combined, the wildtype enzyme andSfInv act synergistically, revealing an entirely new mechanism for cooperative activities driven by complimentary electrostatic interactions at the PET surface. These findings highlight unexplored avenues in improving PETase function through the control of morphological preference or introduction of protein cooperativity by exploiting protein electrostatics.
Chemical shift and relaxation regularisation improve the accuracy of1H MR spectroscopy analysis
Authors: Wilson Martin
Published: January 2025

Purpose

Accurate analysis of metabolite levels from1H MRS data is a significant challenge, typically requiring the estimation of approximately 100 parameters from a single spectrum. Signal overlap, spectral noise and common artefacts further complicate analysis, leading to instability and reports of poor agreement between different analysis approaches. One inconsistently used method to improve analysis stability is known as regularisation, where poorly determined parameters are partially constrained to take a predefined value. In this study we examine how regularisation of frequency and linewidth parameters influences analysis accuracy.

Methods

The accuracy of three MRS analysis methods was compaired: 1) ABfit, 2) ABfit-reg and 3) LCModel, where ABfit-reg is a modified version of ABfit incorporating regularisation. Accuracy was assessed on synthetic MRS data generated with random variability in the frequency shift and linewidth parameters applied to each basis signal. Spectra (N=1000) were generated across a range of SNR values (10, 30, 60, 100) to evaluate the impact of variable data quality.

Results

Comparison between ABfit and ABfit-reg demonstrates a statistically significant (p <0.0005) improvement in accuracy associated with regularisation for each SNR regime. An approximately 10% reduction in the mean squared metabolite errors were found for ABfit-reg compared to LCModel for SNR>10 (p <0.0005). Furthermore, Bland-Altman analysis shows that incorporating regularisation into ABfit enhances its agreement with LCModel.

Conclusion

Regularisation is beneficial for MRS fitting and accurate characterisation of the frequency and linewidth variabilityin vivomay yield further improvements.
In vivomeasurements of receptor tyrosine kinase activity reveal feedback regulation of a developmental gradient
Authors: Ho Emily K. , Kim-Yip Rebecca P. , Simpkins Alison G. , Farahani Payam E. , Oatman Harrison R. , Posfai Eszter , Shvartsman Stanislav Y. , Toettcher Jared E.
Published: January 2025

A lack of tools for detecting receptor activityin vivohas limited our ability to fully explore receptor-level control of developmental patterning. Here, we extend a new class of biosensors for receptor tyrosine kinase (RTK) activity, the pYtag system, to visualize endogenous RTK activity inDrosophila. We build biosensors for threeDrosophilaRTKs that function across developmental stages and tissues. By characterizing Torso::pYtag during terminal patterning in the early embryo, we find that Torso activity differs from downstream ERK activity in two surprising ways: Torso activity is narrowly restricted to the poles but produces a broader gradient of ERK, and Torso activity decreases over developmental time while ERK activity is sustained. This decrease in Torso activity is driven by ERK pathway-dependent negative feedback. Our results suggest an updated model of terminal patterning where a narrow domain of Torso activity, tuned in amplitude by negative feedback, locally activates signaling effectors which diffuse through the syncytial embryo to form the ERK gradient. Altogether, this work highlights the usefulness of pYtags for investigating receptor-level regulation of developmental patterning.
Using magnetoencephalography to track the propagation of 40 Hz invisible spectral flicker
Authors: Henney Mark Alexander , Spaak Eelke , Hansen Henrik Enggaard , Carstensen Marcus , Madsen Kristoffer Hougaard , Oostenveld Robert
Published: January 2025

Brain stimulation with novel 40 Hz invisible spectral flicker (ISF) has been proposed as a therapy for Alzheimer’s disease, with leading hypotheses suggesting local promotion of glymphatic clearance of amyloid as the mechanism of action. Neural signals in the gamma range and their spatial propagation over the brain can be tracked using magnetoencephalography (MEG) with high temporal and good spatial detail. However, stimulation with 40 Hz ISF requires specialised hardware which causes electromagnetic interference (EMI) with MEG equipment.

MEG measures the tiny magnetic fields of the brain, which are easily distorted by external magnetic fields. Using MEG to track the propagation of 40 Hz ISF requires multiple modifications to the experimental setup. These include, at least 1) an experimental design that promotes modulation of the neural signal, but not the artifact, 2) removal of all electronics not strictly necessary for light production from the stimulators, and 3) signal processing for 40 Hz EMI artifact suppression.

Here, we present an MEG study on the cortical propagation of 40 Hz ISF. In two experiments, we investigate the modulation that visual and non-visual cognitive tasks have on the power and propagation of cortical activity induced by 40 Hz ISF.

With the chosen experimental setup and design, the 40 Hz EMI artifact could not be entirely disentangled from the neural signal of interest, thus rendering inference on the spatial propagation of the 40 Hz signal impossible. Further improvements need to be implemented in a follow-up experimental design. We present potential solutions to allow for future investigation of 40 Hz ISF with MEG.
Quantum sensing from gravity as a universal dephasing channel for qubits
Authors: Balatsky Alexander V. , Roushan Pedram , Schaltegger Joris , Wong Patrick J.
Published: January 2025

We investigate the interaction of a transmon qubit with a classical gravitational field. Exploiting the generic phenomena of the gravitational redshift and Aharonov-Bohm phase, we show that entangled quantum states dephase with a universal rate. The gravitational phase shift is expressed in terms of a quantum computing noise channel. We give a measurement protocol based on a modified phase estimation algorithm which is linear in the phase drift, which is optimal for measuring the small phase that is acquired from the gravitation channel. Additionally, we propose qubit-based platforms as quantum sensors for precision gravitometers and mechanical strain gauges as an example of this phenomenon's utility. We estimate a sensitivity for measuring the local gravitational acceleration to be δg/g∼10−7. This paper demonstrates that classical gravitation has a nontrivial influence on quantum computing hardware and provides an illustration of how quantum computing hardware may be utilized for purposes other than computation. While we focus on superconducting qubits, we point to the universal nature of gravitational phase effects for all quantum platforms.

Published by the American Physical Society
2025
Quantum correlations, mixed states, and bistability at the onset of lasing
Authors: Papoff Francesco , Carroll Mark Anthony , Lippi Gian Luca , Oppo Gian-Luca , D'Alessandro Giampaolo
Published: January 2025

We derive a model for a single-mode laser that includes all two-particle quantum correlations between photons and electrons. In contrast to the predictions of semiclassical models, we find that lasing takes place in the presence of quantum bistability between a nonlasing and a nonclassical coherent state. The coherent state is characterized by a central frequency and a finite linewidth and emerges with finite amplitude from a saddle-node bifurcation together with an unstable coherent state. Hence coherent emission in nanolasers originates through a mixing of lasing and nonlasing states. In the limit of a macrolaser with a large number of emitters and nonresonant modes, the laser threshold approaches the prediction of the semiclassical theory, but with the important difference that lasing can be achieved only in the presence of finite-size perturbations.

Published by the American Physical Society
2025
Power loss analysis for the optical cavity of an x-ray laser oscillator
Authors: Tiwari Ganesh , Yu Li Hua , Yang Xi , Shaftan Timur , Smaluk Victor
Published: January 2025

We investigate properties of optical elements in the optical cavity of an x-ray laser oscillator with emphasis on the power loss of a monochromatic Gaussian radiation beam upon passing through them using analytical and numerical approaches. Here we assume the optical cavity comprises of refractive lenses and Bragg crystals exploiting symmetric Bragg scattering. For the lens, we include focusing and curvature effects while we include angular filtering due to finite Darwin width of the Bragg crystal. Our results indicate the feasibility of x-ray power out-coupling in the range of 0.5%–28% with intracavity reflectivity of 67%–95% at 10.321 keV for nominal (≥65% reflectivity) cases. We also show the possibility of achieving high out-coupling of 35%–80% while restricting the intracavity reflectivity in the 19%–62% by adopting lossy cavities with 10–20  μm thin crystals.

Published by the American Physical Society
2025
Electron and light hyperbolicity correlation in
α−CaGe2
Authors: Gao Han , Zhang Xuejin , Ding Chao , Wang Mingzheng , Wang Juan , Yang Bo , Zhao Mingwen
Published: January 2025

Hyperbolic materials, characterized by their hyperbolic dispersion relations of waves, have attracted significant attention due to their distinct equifrequency contours. This study establishes a correlation between electron hyperbolicity and light hyperbolicity, unveiling fascinating scenarios resulting from their interplay. The transition of electron hyperbolicity from type-I to type-II, induced by varying the chemical potential of electrons, also triggers a similar transition in light hyperbolicity. Through first-principles calculations, α−CaGe2 is identified as a promising material for achieving this transition. The tunable optical responses in α−CaGe2 under different doping conditions allow for the creation of heterostructures, resulting in the emergence of unique optical phenomena such as negative refraction and negative reflection. The distinctive electronic states proposed in this study not only pave the way for further exploration of hyperbolic materials but also lay the groundwork for designing innovative optoelectronic devices that expand the functional possibilities of these intriguing materials.

Published by the American Physical Society
2025
Enhanced signal response through synchronization competition in a ring of four bistable systems
Authors: Liang Xiaoming
Published: January 2025

Recent research indicates that small-world networks can enhance weak signals through a phenomenon called topological resonance. However, the underlying mechanism of this effect remains unclear. In this study, we examine a ring of four bistable oscillators to analyze how it responds to an external subthreshold signal. Our findings reveal that the ring amplifies the signal via synchronization competition, where two desynchronized oscillators compete to synchronize with the other two, leading to increased oscillation and improved response to the subthreshold signal. Additionally, we find that synchronization competition is influenced by both the initial states of the oscillators and the characteristics of the subthreshold signal. We identify three synchronization transitions during signal amplification and propose three feedforward motifs to analyze the signal response of the ring. Finally, we apply the synchronization competition mechanism to explain the topological resonance of small-world networks.

Published by the American Physical Society
2025
Machine-learning approach to understanding ultrafast carrier dynamics in the three-dimensional Brillouin zone of
PtBi2
Authors: Majchrzak Paulina , Sanders Charlotte , Zhang Yu , Kuibarov Andrii , Suvorov Oleksandr , Springate Emma , Kovalchuk Iryna , Aswartham Saicharan , Shipunov Grigory , Büchner Bernd , Yaresko Alexander , Borisenko Sergey , Hofmann Philip
Published: January 2025

Using time- and angle-resolved photoemission spectroscopy, we examine the unoccupied electronic structure and electron dynamics of the type-I Weyl semimetal PtBi2. Using the ability to change the probe photon energy over a wide range, we identify the predicted Weyl points in the unoccupied three-dimensional band structure and we discuss the effect of k⊥ broadening in the normally unoccupied states. We characterize the electron dynamics close to the Weyl points and in other parts of three-dimensional Brillouin zone using k-means, an unsupervised machine-learning technique. This reveals distinct differences—in particular, that the electron dynamics close to the Weyl points are slower than in Brillouin zone regions close to the bulk Fermi surface.

Published by the American Physical Society
2025
Crystal structure, Hirshfeld surface analysis and crystal voids of 4-nitrobenzo[c][1,2,5]selenadiazole
Authors: Gurbanov Atash V. , Hökelek Tuncer , Mammadova Gunay Z. , Hasanov Khudayar I. , Javadzade Tahir A. , Belay Alebel N.
Published: January 2025

The title molecule, C6H3N3O2Se, is almost planar. In the crystal, intermolecular C—H...O hydrogen bonds link the molecules into a network structure, enclosing R
2
2(7) and R
3
3(8) ring motifs, parallel to the bc plane. There are π–π interactions present with centroid-to-centroid distances of 3.746 (3) and 3.697 (3) Å. A Hirshfeld surface analysis of the crystal structure indicates that the most important contributions for the crystal packing are from H...O/O...H (19.6%), H...N/N...H (11.0%), H...Se/Se...H (8.5%), O...Se/Se...O (8.2%), H...H (7.4%), C...N/N...C (7.3%) and N...Se/Se...N (7.2%) interactions. Hydrogen bonding and van der Waals interactions are the dominant interactions in the crystal packing. The volume of the crystal voids and the percentage of free space were calculated to be 25.60 Å3 and 3.73%, showing that there is no large cavity in the crystal.
Negative emotions’ impact on consumer satisfaction and loyalty due to failures in financial services: application of the affective-cognitive model
Authors: Sottolichio Alejandro J. , Ponce Hector R. , Rojas Cabezas Germán
Published: January 2025

Purpose

We examine negative emotions’ influence on consumer satisfaction and loyalty when repurchasing a product or service after experiencing failures in the financial services sector.

Design/methodology/approach

The sample comprised 735 valid surveys of customers who encountered such service failures. An initial model incorporating 14 negative emotions was narrowed down to the most robust one, comprising three emotions, after data collection and statistical validation.

Findings

Consumer dissatisfaction is explained by affective (pleasure) rather than cognitive factors (disconfirmation) in the financial services context. Loyalty is influenced only by affective (pleasure and activation) rather than cognitive elements (disconfirmation) in the dissatisfaction generation process, indicating that loyalty is not a cognitive but an affective one. Finally, an affective judgment (activation) rather than a cognitive one (disconfirmation) explains consumer’s recommendation of a product or service despite encountering failures.

Originality/value

This is the first study to focus exclusively on negative emotions, revealing that the pleasure dimension is a significant antecedent of dissatisfaction. By demonstrating that emotional factors rather than cognitive assessments dominate both satisfaction and loyalty responses, this study offers a unique contribution to understanding consumer behavior after service failures in financial services, with practical implications for service recovery strategies.
Role of supply chain resources capabilities on enhancing innovation-based supply chain risk management
Authors: Huma Sehrish , Siddiqui Danish Ahmed
Published: January 2025

Purpose

The purpose of this study is to investigate the roles of potential absorptive capacity (PACAP) and realized absorptive capacity (RACAP) in driving different types of innovation practices, including process, product, marketing and organizational innovation with in the supply chain (SC). Furthermore, this study also seeks to examine the previously unexplored relationship between these SC innovation practices and supply chain risk management (SCRM).

Design/methodology/approach

Data were collected from 267 SC professionals working in the export manufacturing industry for hypotheses testing via structural equation modeling.

Findings

The results have found that both PACAP and RACAP positively and significantly impact on each practice of SC innovation. The results also show that each SC innovation practices such as product innovation, process innovation and marketing innovation have a positive and significant impact on SCRM except organizational innovation.

Originality/value

This study makes a notable contribution to the broader SC management literature, with a specific focus on absorptive capacity, innovation management and SCRM, areas where empirical research is still emerging. This study reveals that organizations trying to manage SC risk must implement sufficient SC innovation practices by enhancing their PACAP and RACAP for quick response and recovery from SC disruptions.
Yuvashakti: where passion meets profession
Authors: Bapat Gautam Surendra , Sane Anjali Ajit
Published: January 2025

Learning outcomes

This case study aims to study cost benefit analysis, economic evaluation and its types, study and understand different costs involved in logistics and to identify the role of dynamic leadership in nonstructured organization.
The impact of the pandemic on management in public sector organisations
Authors: Meierdirk Charlotte , Fleischer Stephanie
Published: January 2025

Purpose

This study investigates management challenges, communication plans and crisis decision-making during the COVID-19 pandemic, plus highlights management excellence for future operations. Using Deloitte Consultancy’s (2015) time frames of organisational crisis management strategies: response, recovery and readiness, this article explores management approaches of the UK’s public sector organisations (PSO) during the COVID-19 pandemic.

Design/methodology/approach

A mixed-method approach consisting of a quantitative survey followed by semi-structured interviews was used. About 33 part-time master’s degree students on a business administration (MBA) course, who were also full-time managers in the UK’s healthcare, education and other PSOs, completed the survey. The survey responses were subsequently used to select nine participants for follow-up semi-structured online interviews.

Findings

Qualitative data showed the importance of speedy decisions and clarity of communication during the pandemic. Teamwork was seen as paramount to successful decision-making despite many changing job roles. On reflection, managers gained confidence in future crisis decision-making with the importance of sharing ideas between departments, but further reflection was needed to prepare for future challenges.

Research limitations/implications

One of the limitations to this research is that the participants are all part-time MBA students, and although they were all full-time managers in PSOs, they may be more critical of the status quo.

Practical implications

Practically, organisations would benefit from reflecting on their reaction to the pandemic and what can be learnt. It is clear the majority of the managers interviewed felt that after the pandemic the organisations just moved on and there was no in-depth reflection on what had happened; the last stage of Deloitte’s (2015) model was never fully realised. The post-pandemic phase is an area that would benefit from further research, as it has now been over four years since the beginning of the pandemic, and some of the positives, such as teamwork and a sense of belonging, seem to have been lost. The pandemic has left organisations with staff absences and long-term illnesses; last year alone workplace absences cost the UK economy £32.7bn (Nolsoe, 2014). To survive, organisations have to be resilient, responsive and flexible. The next challenge will emerge from navigating times of austerity and the need for PSOs to restructure post-pandemic, an area that would benefit from further research.

Originality/value

The COVID-19 pandemic was a crisis that impacted all organisations, including their goals, operations and employees. It was clear that the amount of planning was vast, but as soon as the pandemic was over, quite a few of the organisations went back to the status quo and the “readiness stage” did not happen. The smaller organisations were more likely to reflect and improve than the larger ones.
Exploring the nexus between tourist characteristics and social media’s impact on decision-making: a PLS-MGA based study of Indian tourists
Authors: Gulati Shruti , Kumar Suneel
Published: January 2025

Purpose

This study aims to explore the nexus between tourist’s characteristics and the changing intensity of social media’s impact on tourist decision-making among Indian tourists. A group-based comparison is done in this exploratory study; the basis of groups is the tourist’s characteristics which signifies their different types such as social media type, user type, traveller type and destination type. India, which is a huge market for tourists and social media users, is explored for this study.

Design/methodology/approach

This study adopts an exploratory design where an attempt is made to analyse if the intensity of social media impact on their decision-making changes with different types of tourists. For this purpose, primary data analysis using Partial Least Squares Regression based Multi Group Analysis (PLS-MGA) is performed on 488 Indian Tourists which was collected using a structured online questionnaire. The groups have been divided according to tourist characteristics signifying different types like social media type, user type, traveller type and destination type.

Findings

Social media usage frequency and travel frequency have no moderating effect on social media’s impact on tourist decision-making. But social media type partially moderates decision-making with changing impact on the need recognition, information search and post purchase behaviour stages. Destination type also partially moderates with an impact on post purchase behaviour stage of tourist decision-making. Thus, it can be said that different types of tourists are impacted differently by social media across various stages of decision-making.

Originality/value

This is a novel study that for the first time explores the changes in the impact of social media on tourist decision-making through changes in their own personal characteristics. Also, it provides real-time insights for tourism marketing for Indian market which has huge potential due to Indians being avid travellers and users of social media.