bluuebunny/crossref_metadata_2025 huggingface dataset:
Imaging high-frequency voltage dynamics in multiple neuron classes of behaving mammals
Authors: Haziza Simon , Chrapkiewicz Radoslaw , Zhang Yanping , Kruzhilin Vasily , Li Jane , Li Jizhou , Delamare Geoffroy , Swanson Rachel , Buzsaki Gyorgy , Kannan Madhuvanthi , Vasan Ganesh , Lin Michael Z. , Zeng Hongkui , Daigle Tanya L. , Schnitzer Mark J.
Published: August 2024

Fluorescent genetically encoded voltage indicators report transmembrane potentials of targeted cell-types. However, voltage-imaging instrumentation has lacked the sensitivity to track spontaneous or evoked high-frequency voltage oscillations in neural populations. Here we describe two complementary TEMPO voltage-sensing technologies that capture neural oscillations up to ~100 Hz. Fiber-optic TEMPO achieves ~10-fold greater sensitivity than prior photometry systems, allows hour-long recordings, and monitors two neuron-classes per fiber-optic probe in freely moving mice. With it, we uncovered cross-frequency-coupled theta- and gamma-range oscillations and characterized excitatory-inhibitory neural dynamics during hippocampal ripples and visual cortical processing. The TEMPO mesoscope images voltage activity in two cell-classes across a ~8-mm-wide field-of-view in head-fixed animals. In awake mice, it revealed sensory-evoked excitatory-inhibitory neural interactions and traveling gamma and 3-7 Hz waves in the visual cortex, and previously unreported propagation directions for hippocampal theta and beta waves. These technologies have widespread applications probing diverse oscillations and neuron-type interactions in healthy and diseased brains.
Differences in isotopic compositions of individual grains and aggregated seed samples affect interpretation of ancient plant cultivation practices
Authors: James Nathaniel F. , Winter-Schuh Christine , Kenoyer J. Mark , Guedes Jade D’Alpoim , Makarewicz Cheryl A.
Published: August 2024

The stable carbon (δ13C) and nitrogen (δ15N) isotope analysis of charred archaeological grains provides a remarkably precise scale of information: the growing conditions under which a plant was cultivated in a single field and season. Here we investigate how the measurement of single individual grains or aggregate ‘bulk’ samples for carbon and nitrogen isotopes impacts how we characterize variation and, consequently, our interpretations of ancient cultivation practices. Using experimentally grown barley (Hordeum vulgarevar.nudum), this work investigates δ13C and δ15N intra-panicle variation between both uncharred and charred individual grains from four plants. We found limited intra- and inter-panicle isotopic variation in single grain isotope values, ca. 0.5‰ in δ13C and ca. 1‰ in δ15N, reemphasizing the degree to which grains are representative of their local growing conditions. To explore the interpretive impact of aggregate versus single-grain isotopic sampling, we measured charred barley recovered from a single storage context excavated from Trench 42 (ca. 1900 BCE) at Harappa. Aggregate samples of a random selection of Trench 42 barley demonstrated remarkable inter-sample homogeneity, with a less than 0.5‰ difference in δ13C and δ15N values, reinforcing the ability of aggregate samples to capture a representative isotopic average of a single depositional context. However, the measurement of single-grains revealed moderate 2–3‰ variation in δ13C, and an outstandingly wide isotopic variation of ca. 8‰ in δ15N values, indicating the degree to which cultivation practices varied beyond what the bulk samples indicated. These results highlight how decisions in the selection and measurement of archaeological grains for isotopic analysis impact data resolution, with profound consequences for understanding past agricultural diversity.
Investigation of cell mechanics and migration on DDR2-expressing neuroblastoma cell line
Authors: Vessella Theadora , Rozen Esteban , Shohet Jason , Wen Qi , Zhou Hong Susan
Published: August 2024

Neuroblastoma is a devastating disease accounting for ~15% of all childhood cancer deaths. Collagen content and fiber association within the tumor stroma influence tumor progression and metastasis. High expression levels of collagen receptor kinase, Discoidin domain receptor II (DDR2), are associated with poor survival of neuroblastoma patients. Additionally, cancer cells generate and sustain mechanical forces within their enviroment as a part of their normal physiology. Despite this, whether collagen activated DDR2 signaling dysregulate these migration forces is still elusive. To address these questions, a shRNA DDR2 knockdown neuroblastoma cell line (SH-SY5Y) was engineered to evaluate the consequence of DDR2 on cellular mechanics. Atomic force microscopy and traction force microscopy were utlizing to unveil the biophysical altercations. DDR2 down-regulation was found to significantly reduce proliferation, cell stiffness, and cellular elongation. Aditionally, DDR2 down-regulated cells had decreased traction forces when plated on collagen coated elastic substrates. Together, these results highlight the important role that DDR2 has in reducing migration mechanics in neuroblastoma and might be a promising target for future therapies.
Novel high-content and open-source image analysis tools for profiling mitochondrial morphology in neurological cell models
Authors: Chin Marcus Y. , Joy David A. , Samaddar Madhuja , Rana Anil , Chow Johann , Miyamoto Takashi , Calvert Meredith
Published: August 2024

Mitochondria undergo dynamic morphological changes depending on cellular cues, stress, genetic factors, or disease. The structural complexity and disease-relevance of mitochondria have stimulated efforts to generate image analysis tools for describing mitochondrial morphology for therapeutic development. Using high-content analysis, we measured multiple morphological parameters and employed unbiased feature clustering to identify the most robust pair of texture metrics that described mitochondrial state. Here, we introduce a novel image analysis pipeline to enable rapid and accurate profiling of mitochondrial morphology in various cell types and pharmacological perturbations. We applied a high-content adapted implementation of our tool, MitoProfilerHC, to quantify mitochondrial morphology changes in i) a mammalian cell dose response study and ii) compartment-specific drug effects in primary neurons. Next, we expanded the usability of our pipeline by using napari, a Python-powered image analysis tool, to build an open-source version of MitoProfiler and validated its performance and applicability. In conclusion, we introduce MitoProfiler as both a high-content-based and an open-source method to accurately quantify mitochondrial morphology in cells, which we anticipate to greatly facilitate mechanistic discoveries in mitochondrial biology and disease.
Allosteric Regulation of Pyruvate Kinase Enables Efficient and Robust Gluconeogenesis by Preventing Metabolic Conflicts and Carbon Overflow
Authors: She Fukang , Anderson Brent W. , Khana Daven B. , Zhang Shenwei , Steinchen Wieland , Fung Danny K. , Lucas Lauren N. , Lesser Nathalie G. , Stevenson David M. , Astmann Theresa J. , Bange Gert , van Pijkeren Jan-Peter , Amador-Noguez Daniel , Wang Jue D.
Published: August 2024

Glycolysis and gluconeogenesis are reciprocal metabolic pathways that utilize different carbon sources. Pyruvate kinase catalyzes the irreversible final step of glycolysis, yet the physiological function of its regulation is poorly understood. Through metabolomics and enzyme kinetics studies, we discovered that pyruvate kinase activity is inhibited during gluconeogenesis in the soil bacteriumBacillus subtilis. This regulation involves an extra C-terminal domain (ECTD) of pyruvate kinase, which is essential for autoinhibition and regulation by metabolic effectors. Introducing a pyruvate kinase mutant lacking the ECTD intoB. subtilisresulted in defects specifically under gluconeogenic conditions, including inefficient carbon utilization, slower growth, and decreased resistance to the herbicide glyphosate. These defects are not caused by the phosphoenolpyruvate-pyruvate-oxaloacetate futile cycle. Instead, we identified two significant metabolic consequences of pyruvate kinase dysregulation during gluconeogenesis: increased carbon overflow into the medium and failure to expand glycolytic intermediates such as phosphoenolpyruvate (PEP). In silico analysis revealed that in wild-type cells, an expanded PEP pool enabled by pyruvate kinase regulation is critical for the thermodynamic feasibility of gluconeogenesis. Our findings underscore the importance of allosteric regulation during gluconeogenesis in coordinating metabolic flux, efficient energy utilization, and antimicrobial resistance.
RAF inhibitors activate the integrated stress response by direct activation of GCN2
Authors: Gilley Rebecca , Kidger Andrew M. , Neill Graham , Severson Paul , Byrne Dominic P. , Kenneth Niall S. , Bollag Gideon , Zhang Chao , de Oliveira Taiana Maia , Eyers Patrick A. , Bayliss Richard , Masson Glenn R. , Cook Simon J.
Published: August 2024

Paradoxical RAF activation by chemical RAF inhibitors (RAFi) is a well-understood ‘on-target’ biological and clinical response. In this study, we show that a range of RAFi drive ERK1/2-independent activation of the Unfolded Protein Response (UPR), including expression of ATF4 and CHOP, that required the translation initiation factor eIF2α. RAFi-induced ATF4 and CHOP expression was not reversed by inhibition of PERK, a known upstream activator of the eIF2α-dependent Integrated Stress Response (ISR). Rather, we found that RAFi exposure activated GCN2, an alternate eIF2α kinase, leading to eIF2α-dependent (and ERK1/2-independent) ATF4 and CHOP expression. The GCN2 kinase inhibitor A-92, GCN2 RNAi, GCN2 knock-out or ISRIB (an eIF2α antagonist) all reversed RAFi-induced expression of ATF4 and CHOP indicating that RAFi require GCN2 to activate the ISR. RAFi also activated full-length recombinant GCN2in vitroand in cells, generating a characteristic ‘bell-shaped’ concentration-response curve, reminiscent of RAFi-driven paradoxical activation of WT RAF dimers. Activation of the ISR by RAFi was abolished by GCN2 kinase dead mutations and M802A or M802G gatekeeper mutations, suggesting that RAFi bind directly to the GCN2 kinase domain; this was supported by mechanistic structural models of RAFi interaction with GCN2. Since the ISR is a critical pathway for determining cell survival or death, our observations may be relevant to the clinical use of RAFi, where paradoxical GCN2 activation may be a previously unappreciated off-target effect that may modulate tumour cell responses.
Failure to resolve inflammation contributes to juvenile onset cardiac damage in a mouse model of Duchenne Muscular Dystrophy
Authors: Novak James S. , Lischin Amy , Uapinyoying Prech , Hindupur Ravi , Moon Young Jae , Bhattacharya Surajit , Tiufekchiev Sarah , Barone Victoria , Mázala Davi A. G. , Gamu Iteoluwakishi H. , Walters Gabriela , Jaiswal Jyoti K.
Published: August 2024

Absence of dystrophin protein causes cardiac dysfunction in patients with Duchenne muscular dystrophy (DMD). Unlike boys with DMD, the common mouse model of DMD (B10-mdx) does not manifest cardiac deficits until late adulthood. This has limited our understanding of the mechanism and therapeutic approaches to target the pediatric onset of cardiac pathology in DMD. Here we show that themdxmouse model on the DBA/2J genetic background (D2-mdx) displays juvenile-onset cardiac degeneration. Molecular and histological analysis revealed that cardiac damage in this model is linked to increased leukocyte chemotactic signaling and an inability to resolve inflammation. These deficiencies result in chronic inflammation and fibrotic conversion of the extracellular matrix (ECM) in the juvenile D2-mdx heart. To address these pathologies, we tested the utility of pro-resolution therapy to clear chronic cardiac inflammation. Use of an N-formyl peptide receptor (FPR) agonist helped physiologically resolve inflammation and mitigate the downstream events that lead to fibrotic degeneration of cardiomyocytes, preventing juvenile onset cardiac muscle loss. These results establish the utility of D2-mdxmodel to study events associated with pediatric-onset cardiac damage and demonstrates pro-resolution therapy as an alternate to anti-inflammatory therapy for treating cardiac degenerative pathology responsible for cardiomyopathy in DMD patients.
Ubiquitination mediates protein localization in RNA virus-infected cells
Authors: Shi Shihua , Iesmantavicius Vytautas , Sabu Amit Santhu , Soneson Charlotte , Kohler Hubertus , Sanchez Jacint , Ghosh Sucheta , Cao Chun , Huang Yong , Matthias Gabriele , Yamauchi Yohei , Matthias Patrick , Wang Longlong
Published: August 2024

Viruses trigger monocytes’ proinflammatory and antiviral responses. Ubiquitination, a post-translational modification primarily marking proteins for degradation, regulates cellular responses to virus infection. However, a comprehensive analysis of virus-induced ubiquitination in monocytes is lacking. Here we identified a widespread increase of ubiquitination under viral RNA challenge or influenza infection in monocytes. Systematic proteome studies revealed that influenza infection elicits dynamic ubiquitinome alterations, with a notable transition from early to late stage. Most of this increased ubiquitination is not proteolytic and targets proteins involved in subcellular localization, such as the mitochondrial protein COA7 which, when ubiquitinated during infection, translocates to the nucleus and inhibits stress granules formation and TNF-α expression. Blocking ubiquitination halts viral ribonucleoprotein’s nuclear export, highlighting ubiquitination’s importance for protein localization during virus infection.
Semi-Automatic Segmentation ofPseudomonas koreensisandEscherichia colifor Bacterial Growth Characterization
Authors: Alvarado-Ruiz Diana A. , Ordaz-Hernández Keny , Díaz-Jiménez Lourdes , Lara-Cadena Grecia L. , González-López Roberto , Vargas-Gutiérrez Gregorio , Castelán Mario
Published: August 2024

Bacterial characterization is a crucial discipline within microbiology. Given the manual and labor-intensive nature of this task, our aim is to introduce a semi-automatic segmentation method that enhances efficiency while preserving the rich details of bacterial colonies. We propose using the k-means clusterization algorithm to analyze and segment images of bacterial cultures, specifically those ofPseudomonas koreensisandEscherichia coli. Unlike existing methods that focus primarily on colony counting, our approach emphasizes morphological characterization. In some bacterial cultures, colonies are not well-defined, making manual counting or other automated counting methods unfeasible; i.e. the bacterial growth area is not easily identifiable, thus precise growth tracking is not feasible. Our method enables bacterial growth characterization even in these cases. Our computer vision system identifies and quantifies the diverse morphologies withinP. koreensisandE. colicultures, determining their relative occupancy in an image. Our approach provides valuable insights into the composition, growth patterns, and developmental stages of bacterial colonies, designed to assist both novice and expert microbiologists in bacterial analysis.
Annotation of piRNA source loci in the genome of non-model insects
Authors: Halbach Rebecca , van Rij Ronald P.
Published: August 2024

The PIWI-interacting RNA (piRNA) pathway plays a crucial role in the defense of metazoan genomes against parasitic transposable elements. The major source of piRNAs in the model organismDrosophila melanogasterare defective transposon copies located in piRNA clusters – genomic regions with a high piRNA density that are thought to serve as an immunological memory of past invasion by those elements. Different approaches have been used to annotate piRNA clusters in model organisms like flies, mice and rats, and software such as proTRAC or piClust are available for piRNA cluster annotation. However, these software often make assumptions based on current knowledge of piRNA clusters from (mostly vertebrate) model organisms, which do not necessarily hold true for non-model insects in which the piRNA pathway is less understood. Here we describe a simple piRNA cluster annotation approach that utilizes very little assumptions on the biology of the piRNA pathway. The pipeline has been validated on mosquito genomes but can be easily used for other non-model insect species as well.
Calcium transfer from the ER to other organelles for optimal signaling inToxoplasma gondii
Authors: Li Zhu-Hong , Asady Beejan , Chang Le , Hortua Triana Miryam Andrea , Li Catherine , Coppens Isabelle , Moreno Silvia N.J.
Published: August 2024

Ca2+signaling in cells begins with the opening of Ca2+channels in either the plasma membrane (PM) or the endoplasmic reticulum (ER) and results in a dramatic increase in the physiologically low (<100 nM) cytosolic Ca2+level. The temporal and spatial Ca2+levels are well regulated to enable precise and specific activation of critical biological processes. Ca2+signaling regulates pathogenic features of apicomplexan parasites likeToxoplasma gondiiwhich infects approximately one-third of the world’s population.T. gondiirelies on Ca2+signals to stimulate traits of its infection cycle and several Ca2+signaling elements play essential roles in its parasitic cycle. Active egress, an essential step for the infection cycle ofT. gondiiis preceded by a large increase in cytosolic Ca2+most likely by release from intracellular stores. Intracellular parasites take up Ca2+from the host cell during host Ca2+signaling events to replenish intracellular stores. In this work, we investigated the mechanism by which intracellular stores are replenished with Ca2+and demonstrated a central role for the SERCA-Ca2+-ATPase in keeping not only the ER filled with Ca2+but also other stores. We show mitochondrial Ca2+uptake, by transfer of Ca2+from the ER likely through membrane contact sites. We propose a central role for the ER in sequestering and redistributing calcium to other intracellular organelles following influx at the PM.

HIGHLIGHTS

TheT. gondiiER efficiently takes up Ca2+that enters the cytosol from the extracellular milieu.

Filling of acidic stores inT. gondiiappears to be dependent on the filling of the ER

The mitochondrion ofT. gondiihas no direct access to extracellular calcium but is able to take up Ca2+by transfer from the ER and/or acidic stores
PhOxi-seq detects enzyme-dependent m2G in multiple RNA types
Authors: Klimontova Marie , Kim Chung Kimberley Chung , Zhang Han , Kouzarides Tony , Bannister Andrew J , Hili Ryan
Published: August 2024

In recent years, RNA-modifying enzymes have gained significant attention due to their impact on critical RNA-based processes, and consequently human pathology. However, identifying sites of modifications throughout the transcriptome remains challenging largely due to the lack of accurate and sensitive detection technologies. Recently, we described PhOxi-seq as a method capable of confirming known sites of m2G within abundant classes of RNA, namely purified rRNA and purified tRNA. Here, we further explore the selectivity of PhOxi-seq and describe an optimised PhOxi-seq workflow, coupled to a novel bioinformatic pipeline, that is capable of detecting enzyme-dependent m2G sites throughout the transcriptome, including low abundant mRNAs. In this way, we generated the first database of high confidence sites of THUMPD3-dependent m2G in multiple RNA classes within a human cancer cell line and further identify non-THUMPD3 controlled sites throughout the transcriptome.
The ubiquitin-proteasome system regulates the formation of specialized ribosomes during high salt stress in yeast
Authors: Yang Yoon-Mo , Karbstein Katrin
Published: August 2024

Rps26-deficient ribosomes are a physiologically relevant ribosome population which arises during osmotic stress to support the translation of mRNAs involved in the response to high salt in yeast. They are formed by binding of the chaperone Tsr2 to fully assembled ribosomes to release Rps26 when intracellular Na+concentrations rise. Tsr2-mediated Rps26 release is reversible, enabling a rapid response that conserves ribosomes. However, because the concentration of Tsr2 relative to ribosomes is low, how the released Rps26•Tsr2 complex is managed to allow for accumulation of Rps26-deficient ribosomes to nearly 50% of all ribosomes remains unclear. Here we show that released Rps26 is degraded via the Pro/N-degron pathway, enabling the accumulation of Rps26-deficient ribosomes. Substitution of the N-terminal proline of Rps26 to serine increases the stability of free Rps26, limits the accumulation of Rps26-deficient ribosomes and renders yeast sensitive to high salt. The GID-complex, an E3 ubiquitin ligase, and its adaptor Gid4, mediate polyubiquitination of Rps26 at Lys66 and Lys70. Moreover, this ubiquitination event is required for Rps26 degradation, the accumulation of Rps26-deficient ribosomes and the high salt stress resistance. Together, the data show that targeted degradation of released Rps26 from the Rps26•Tsr2 complex allows Tsr2 to be recycled, thus facilitating multiple rounds of Rps26 release.
EmergingClostridioides difficileribotypes have divergent metabolic phenotypes
Authors: Midani Firas S. , Danhof Heather A. , Mathew Nathanael , Ardis Colleen K. , Garey Kevin W. , Spinler Jennifer K. , Britton Robert A.
Published: August 2024

Clostridioides difficileis a gram-positive spore-forming pathogen that commonly causes diarrheal infections in the developed world. AlthoughC. difficileis a genetically diverse species, certain ribotypes are overrepresented in human infections. It is unknown if metabolic adaptations are essential for the emergence of these epidemic ribotypes. Here, we tested carbon substrate utilization by 88C. difficileisolates and looked for differences in growth between 22 ribotypes. By profiling clinical isolates, we assert thatC. difficileis a generalist species capable of growing on a variety of carbon substrates. Further,C. difficilestrains clustered by phylogenetic relationship and displayed ribotype-specific and clade-specific metabolic capabilities. Surprisingly, we observed that two emerging lineages, ribotypes 023 and 255, have divergent metabolic phenotypes. In addition, althoughC. difficileClade 5 is the most evolutionary distant clade and often detected in animals, it displayed more robust growth on simple dietary sugars than Clades 1-4. Altogether, our results corroborate the generalist metabolic strategy ofC. difficileand demonstrate lineage-specific metabolic capabilities. In addition, our approach can be adapted to the study of additional pathogens to ascertain their metabolic niches in the gut.

IMPORTANCE

The gut pathogenClostridioides difficileutilizes a wide range of carbon sources. Microbial communities can be rationally designed to combatC. difficileby depleting its preferred nutrients in the gut. However,C. difficileis genetically diverse with hundreds of identified ribotypes and most of its metabolic studies were performed with lab-adapted strains. Here, we profiled carbon metabolism by a myriad ofC. difficileclinical isolates. While the metabolic capabilities of these isolates clustered by their genetic lineage, we observed surprising metabolic divergence between two emerging lineages. We also found that the most genetically distant clade grew robustly on simple dietary sugars, posing intriguing questions about the adaptation ofC. difficileto the human gut. Altogether, our results underscore the importance of considering the metabolic diversity of pathogens in the study of their evolution and the rational design of therapeutic interventions.
Human-derived microRNA 21 regulates indole and L-tryptophan biosynthesis transcripts in a prominent gut symbiont
Authors: Flanagan Kayla , Gassner Kirsten , Lang Michaela , Ozelyte Jurgita , Hausmann Bela , Crepaz Daniel , Pjevac Petra , Gasche Christoph , Berry David , Vesely Cornelia , Pereira Fatima C.
Published: August 2024

In the gut, microRNAs (miRNAs) produced by intestinal epithelial cells are secreted into the lumen and can shape the composition and function of the gut microbiome. Crosstalk between gut microbes and the host plays a key role in irritable bowel syndrome (IBS) and inflammatory bowel diseases, yet little is known about how the miRNA-gut microbiome axis contributes to the pathogenesis of these conditions. In this study, we aimed to explore the ability of miR-21, a miRNA that we found decreased in stool samples from IBS patients, to associate with and regulate gut microbiome function. Incubation of human faecal microbiota with miR-21 revealed a rapid association with microbial cells, reproducible across multiple donor samples. Fluorescence-activated cell sorting and sequencing of microbial cells incubated with fluorescently-labelled miR-21 identified organisms belonging to the generaBacteroides,Limosilactobacillus,Ruminococcus, orCoprococcuswhich predominantly interacted with miR-21. Surprisingly, these and other genera also interacted with a miRNA scramble control, suggesting that physical interaction and/or uptake of these miRNAs by gut microbiota is not sequence-dependent. Nevertheless, transcriptomic analysis of the gut commensalBacteroides thetaiotaomicronrevealed a miRNA sequence-specific effect on bacterial transcript levels. Supplementation of miR-21, but not of small RNA controls resulted in significantly altered levels of many cellular transcripts and increased transcription of a biosynthetic operon for indole and L-tryptophan, metabolites known to regulate host inflammation and colonic motility. Our study identifies a novel putative miR-21-dependent pathway of regulation of intestinal function through the gut microbiome with implications for gastrointestinal conditions.
Sequence action representations contextualize during rapid skill learning
Authors: Dash Debadatta , Iwane Fumiaki , Hayward William , Salamanca-Giron Roberto , Bonstrup Marlene , Buch Ethan , Cohen Leonardo G
Published: August 2024

Activities of daily living rely on our ability to acquire new motor skills composed of precise action sequences. Early learning of a new sequential skill is characterized by steep performance improvements that develop predominantly during rest intervals interspersed with practice, a form of rapid consolidation. Here, we ask if the millisecond level neural representation of an action performed at different locations within a skill sequence contextually differentiates or remains stable as learning evolves. Optimization of machine learning decoders to classify sequence-embedded finger movements from MEG activity reached approximately 94% accuracy. The representation manifolds of the same action performed in different sequence contexts progressively differentiated during rest periods of early learning, predicting skill gains. We conclude that sequence action representations contextually differentiate during early skill learning, an issue relevant to brain-computer interface applications in neurorehabilitation.
Four loop renormalization in six dimensions using forcer
Authors: Gracey J. A.
Published: August 2024

We employ the algorithm to renormalize a variety of six dimensional field theories to four loops. In order to achieve this we construct the master integrals in six dimensions from their four dimensional counterparts by using the Tarasov method. The ε expansion of the six dimensional masters are determined up to weight 9 where d=6−2ε. By applying the routine the four loop MS¯ renormalization of ϕ3 theory is reproduced before gauge theories are considered. The renormalization of these theories is also determined in the MOM˜ scheme. For instance the absence of ζ4 and ζ6 is confirmed to five loops in the MOM˜ renormalization of ϕ3 theory. We also evaluate the three loop β-function of the gauge coupling in six dimensional QCD.

Published by the American Physical Society
2024
Compton Amplitude for Rotating Black Hole from QFT
Authors: Cangemi Lucile , Chiodaroli Marco , Johansson Henrik , Ochirov Alexander , Pichini Paolo , Skvortsov Evgeny
Published: August 2024

We construct a candidate tree-level gravitational Compton amplitude for a rotating Kerr black hole, for any quantum spin s=0,1/2,1,…,∞, from which we extract the corresponding classical amplitude to all orders in the spin vector Sμ. We use multiple insights from massive higher-spin quantum field theory, such as massive gauge invariance and improved behavior in the massless limit. A chiral-field approach is particularly helpful in ensuring correct degrees of freedom, and for writing down compact off-shell interactions for general spin. The simplicity of the interactions is echoed in the structure of the spin-s Compton amplitude, for which we use homogeneous symmetric polynomials of the spin variables. Where possible, we compare to the general-relativity results in the literature, available up to eighth order in spin.

Published by the American Physical Society
2024
Controllable suppression of the unconventional superconductivity in bulk and thin-film
Sr2RuO4
via high-energy electron irradiation
Authors: Ruf Jacob P. , Noad Hilary M. L. , Grasset Romain , Miao Ludi , Zhakina Elina , McGuinness Philippa H. , Nair Hari P. , Schreiber Nathaniel J. , Kikugawa Naoki , Sokolov Dmitry , Konczykowski Marcin , Schlom Darrell G. , Shen Kyle M. , Mackenzie Andrew P.
Published: August 2024

In bulk Sr2RuO4, the strong sensitivity of the superconducting transition temperature Tc to nonmagnetic impurities provides robust evidence for a superconducting order parameter that changes sign around the Fermi surface. In superconducting epitaxial thin-film Sr2RuO4, the relationship between Tc and the residual resistivity ρ0, which in bulk samples is taken to be a proxy for the low-temperature elastic scattering rate, is far less clear. Using high-energy electron irradiation to controllably introduce point disorder into bulk single-crystal and thin-film Sr2RuO4, we show that Tc is suppressed in both systems at nearly identical rates. This suggests that part of ρ0 in films comes from defects that do not contribute to superconducting pairbreaking and establishes a quantitative link between the superconductivity of bulk and thin-film samples.

Published by the American Physical Society
2024
Does psychological empowerment transmit the effects of organizational justice on employees' knowledge sharing? A study on the Indian hospitality industry
Authors: Srivastava Shalini , Singh Anupriya , Bali Shivani
Published: August 2024

Purpose

This paper aims to investigate the associations between organizational justice dimensions and employees' knowledge sharing (KS) while studying the mediating role of psychological empowerment (PE) in context of the Indian hospitality industry. It is also aimed to investigate the association between KS and innovative work behavior (IWB).

Design/methodology/approach

A mediation model was verified utilizing three-wave survey data from 293 employees working in hotels situated in northern India. Hypotheses were tested using AMOS and PROCESS Model 4.

Findings

There are significant associations between justice dimensions and KS, and PE mediates these relationships. Additionally, employees' KS has a positive effect on their IWB.

Practical implications

Organizations must promote justice and psychologically empower their employees to facilitate KS. Our study also highlights the significance of employees' KS in encouraging their IWBs. HR leaders and managers have an important role in facilitating the right work environment, in which employees experience fairness and empowerment.

Originality/value

This paper is the first to investigate linkages between justice dimensions, PE, KS and IWB in context of the Indian hospitality industry. Furthermore, this study has made the maiden attempt of asserting the mediating role of PE in the relationship between justice dimensions and KS.
Drivers of platform ecosystem adoption: does innovation capability translate these drivers into improved firm performance
Authors: Sun Xinbo , Abdullahi Usman Magaji
Published: August 2024

Purpose

Building on the theory of resource-based view (RBV), this paper is determined to explore the key drivers that drive platform ecosystem adoption by small businesses and mediation mechanisms that facilitate the translation of these drivers into improved firm financial and nonfinancial performance.

Design/methodology/approach

In this study, structural equation modeling is used to analyze the data. A survey questionnaire was taken from 430 small businesses operating their businesses on various digital platform ecosystems in China to investigate the links between parameters by testing hypotheses. Digital startups operating their businesses on popular Chinese platform ecosystems, including Alibaba, Taobao, Jingdong, Maituan and HelloChe, were chosen.

Findings

The finding deciphers a nuanced interplay of the adoption drivers, with innovation capability emerging as a mediation mechanism translating these drivers into improved financial and non-financial performance.

Research limitations/implications

The acknowledgment of potential drawbacks, such as the focus on specific drivers of platform ecosystem adoption, highlights the need for future research to explore additional factors that may influence adoption decisions. By examining institutional factors, market conditions or external shocks like the COVID-19 pandemic, researchers can provide a more comprehensive understanding of the complexities surrounding platform ecosystem dynamics and offer insights into adaptive strategies for businesses facing uncertainty.

Practical implications

The outcome benefits policymakers and ecosystem designers by creating and overseeing platform ecosystems that support the highlighted drivers. This study further serves as a roadmap for both platform owners and prospective small enterprises as they map their path toward the digital frontier.

Social implications

The findings from the research indicate that small enterprises that embrace platform ecosystems can experience improved financial and non-financial performance, which in turn promotes economic development and the generation of jobs. By utilizing innovative strategies and maximizing their strategic advantages, these enterprises can not only prosper but also make significant contributions to community development and help alleviate joblessness. This highlights the significance of assisting with the incorporation of digital technology in small businesses to achieve wider societal advantages.

Originality/value

Research originality lies in bridging the gap between strategic inputs and measurable outcomes, stressing the vital function of a firm’s innovation in turning ecosystem-driven opportunities into enhanced performance. This means the pivotal role of this study lies in exploring platform ecosystem adoption drivers based on the theory of RBV and the way innovation capability of platform ecosystems facilitates the translation of these drivers into improved financial and nonfinancial performance.
Overall fairness perception and organizational citizenship behaviour: understanding the moderating and mediating factors
Authors: Kyei-Poku Ivy
Published: August 2024

Purpose

Synthesizing theories of leadership, organizational fairness and organizational citizenship behaviour (OCB). This study explores how overall organizational fairness affects OCB by considering the mediating role of organization-based self-esteem (OBSE) and the moderating role of authentic leadership.

Design/methodology/approach

In two phases, survey data were collected from 79 job incumbents at a financial company.

Findings

The findings suggest that authentic leadership significantly affects the relationship between overall fairness perceptions and OCB. Moreover, OBSE was found to act as a mediator in this relationship.

Research limitations/implications

Authentic leadership and organizational self-esteem play crucial roles in fostering a fair work environment that encourages employees to engage in citizenship behaviour. These findings underscore the importance of authentic leadership and OBSE in creating a fair work environment. These findings have implications for human resource management practices and leadership development programs.

Originality/value

Scholars in organizational behaviour have posited that fairness in the workplace is critical to facilitating effective leadership. However, more research is needed to investigate the interplay and mediating effects of fairness and leadership. The present study offers novel insights into the mediating mechanism of OBSE and its critical role in explaining the positive impact of overall fairness on employees’ OCB.
“A pleasant walk on the Pakihi”: ecological orientations in mid-century nature study
Authors: Kelly Frances Jennifer
Published: August 2024

Purpose

A recent United Nations (2021) report stated that education needs to be concerned with enhancing human relationships with the natural world if we are to work toward building a sustainable future. This paper proposes that educational practices underpinned by an ecological orientation in mid-century Aotearoa offer insights for educators looking to enhance human connection with nature. It also argues that ecological thinking has implications for how research in the history of education might be carried out.

Design/methodology/approach

The article responds to recent calls in history of education for researchers to attend to the intertwined ecologies of living and material worlds in research approaches by Maria Tamboukou (2020) and Karin Priem (2022). It conducts a close analysis of a 1952 nature diary, encountered in the national archive, written by a 9-year-old pupil on the West Coast of the South Island. The analysis attends to the human–nature interactions the diary records, and to the resonance of the text in the context of post-war curriculum changes.

Findings

Post-war nature study in Aotearoa New Zealand built on an aim to nurture children’s connections with nature and to place. Analysis of an entry from the 1952 nature diary highlights these connections and demonstrates the possibilities for a reframing of human–nature relationships that emerge with an ecological orientation in education. These findings speak to urgent contemporary concerns with environmental sustainability and human–nature relationships.

Originality/value

The paper draws on educational philosophy and theory (Fesmire, 2012; Nicol, 2014) alongside recent conversations in the history of education (Priem, 2022; Grosvenor and Priem, 2022; Tamboukou, 2020) to consider human–nature relationality at the heart of ecological thought. It outlines an approach to archival research that is ecologically oriented, generating openness and receptivity to the material world.
The internationalization of digital platform firms: the platform-OLI (P-OLI) framework
Authors: Surana Ankit , Chavan Meena , Kumar Vikas , Chirico Francesco
Published: August 2024

Purpose

The aim of this paper is to explore the internationalization of digital platform firms, specifically to investigate the advantages digital platform firms build during the internationalization journey, which helps them overcome the liability of foreignness. More importantly, drawing on network theory and Luo’s framework of new OLI advantages, a new framework of Platform OLI (P-OLI) advantages is developed for digital platform firms.

Design/methodology/approach

This study adopts a multi-case method to empirically understand the internationalization phenomenon of digital platform firms in the emerging economy of India, which is a less researched area. Twenty semi-structured interviews from top executives of 12 Indian headquartered digital platform firms were inductively analyzed based on Gioia’s method, and a cross-case examination was conducted to explore the respondent firm’s internationalization journey.

Findings

Several novel open resource and linkage advantages were identified for digital platform firms that are not covered by the new OLI advantages proposed by Luo. Furthermore, a new “I” advantage, which is information and knowledge advantage, has evolved from the data. This resulted in enhancing the scope of the new OLI framework and network theory and further enabled us to develop the P-OLI framework, a new framework for digital platform firms that reflects the specific advantages a digital platform firm builds during internationalization.

Originality/value

This is the first study which evaluates the new OLI framework from the perspective of a digital platform firm to develop a novel framework, P-OLI. Further, this study is among the few studies with an Indian digital platform firm focus and relies on primary interview data to study digital platform firms’ internationalization phenomenon.
Shaping the future: discursive practices in promoting public relations education at UK universities
Authors: Zeler Ileana , Bridgen Elizabeth
Published: August 2024

Purpose

This study aims to provide a comprehensive analysis of how discursive practices shape the promotion of public relations undergraduate programmes in the context of market-driven UK higher education.

Design/methodology/approach

Research combines a descriptive analysis of the UK universities offering public relations undergraduate degrees and a critical discourse analysis of the online prospectus entries of 25 public relations undergraduate programmes (often called “courses” in the UK), focussing on the course/programme overview and career path sections.

Findings

This wide-ranging review of UK universities’ communication of their public relations provision demonstrates that although the student as consumer has choice, the presentation of the programmes is sometimes “headline grabbing” and often positions public relations as a tactical subject, emphasising promotion and practical skills. Overall, public relations is taught alongside subjects such as marketing, journalism and advertising, and these subjects are foregrounded in promotional material when discussing teaching and potential career paths. Public relations is a difficult subject to explain within the confines of a university prospectus, with the result that it is frequently presented as a promotional practice with little connection to management, leadership or academic research.

Originality/value

To the best authors' knowledge, this is the first study exploring the discursive practices that shape the promotion of public relations undergraduate programmes in UK universities.
When does entrepreneurial leadership enhance supply chain resilience? A three-way interaction analysis
Authors: Al-Swidi Abdullah Kaid , Al-Hakimi Mohammed A. , Al-Hosam Asma , Al Koliby Ibraheem Saleh
Published: August 2024

Purpose

The research on entrepreneurial leadership (EL) and supply chain resilience (SCR) relationship is still in its exploration stage. Previous research indicates that EL is important for enhancing supply chain performance, including its resilience. However, the conditions through which EL affects SCR remain unclear. The purpose of this study is to examine the effect of EL on SCR in the context of SMEs, in addition to explore the combined moderating effects of big data analytics capability (BDAC) and environmental dynamism (ED) in the EL–SCR relationship.

Design/methodology/approach

Hierarchical regression analysis via PROCESS Macro was used to analyze the data collected from manufacturing SMEs in India.

Findings

The findings reveal that EL positively and significantly affects SCR. Importantly, BDAC actually positively moderates the EL–SCR relationship regardless of the level of dynamism of the business environment.

Originality/value

This research expands the existing body of knowledge on EL and SCR within the context of developing countries. The findings offer useful insights for SME managers and decision-makers, who are anticipated to consider the adoption of BDAC in their firms. This has implications that with BDAC adoption, it is anticipated that SMEs will be able to take advantage of the full potential of EL to enhance their SCR regardless of the level of dynamism of the business environment.
Nurses’ actions for Covid-19 patients' transitioning from hospital to home: a scoping review
Authors: Lanzoni Gabriela Marcellino de Melo , Cechinel-Peiter Caroline , Wachholz Laísa Fischer , Backman Chantal , Costa Maria Fernanda Baeta Neves Alonso da , Santos José Luis Guedes dos , Schaefer Ferreira de Mello Ana Lúcia
Published: August 2024

Purpose

To map nurses’ actions performed during the care transitions from hospital to home of Covid-19 patients.

Design/methodology/approach

A scoping review based on the Joanna Briggs Institute guidelines was carried out. We searched in seven databases: PubMed/MEDLINE, BDENF, LILACS, SciELO, Embase, Scopus, Web of Science and Google Scholar. A two-step screening process and data extraction was performed independently by two reviewers. The findings were summarized and analyzed using a content analysis technique.

Findings

Of the total 5,618 studies screened, 21 were included. The analysis revealed nurses’ actions before and after patient’ discharge, sometimes planned and developed with the interprofessional team. The nurses’ actions included to plan and support patients’ discharge, to adapt the care plan, to use screening tools and monitor patients’ clinical status and needs, to provide health orientation to patients and caregivers, home care and face-to-face visiting, to communicate with patients, caregivers and other health professionals with phone calls and virtual tools, to provide rehabilitation procedures, to make referrals and to orient patients and families to navigate in the health system.

Practical implications

The results provide a broader understanding of the actions taken and challenges faced by nurses to ensure a safe care transition for Covid-19 patients from hospital to home. The interprofessional integration to discharge planning and the clinical nursing leadership in post-discharge monitoring were highlighted.

Originality/value

The nurses’ actions for Covid-19 patients performed during care transitions focused on coordination and discharge planning tailored to the needs of patients and caregivers at the home setting. Nurses monitored patients, with an emphasis on providing guidance and checking clinical status using telehealth tools.