bluuebunny/crossref_metadata_2025 huggingface dataset:
Bursts of rapid diversification, dispersals out of southern Africa, and two origins of dioecy punctuate the evolution ofAsparagus
Authors: Bentz Philip C. , Burrows John E. , Burrows Sandra M. , Mizrachi Eshchar , Liu Zhengjie , Yang Jun-Bo , Mao Zichao , Popecki Margot , Seberg Ole , Petersen Gitte , Leebens-Mack Jim
Published: July 2024

The genusAsparagusarose approximately 9–15 million years ago (Ma) and transitions from hermaphroditism to dioecy (separate sexes) occurred ∼3–4 Ma. Roughly 27% of extantAsparagusspecies are dioecious, while the remaining are bisexual with monoclinous flowers. As such,Asparagusis an ideal model taxon for studying early stages of dioecy and sex chromosome evolution in plants. Until now, however, understanding of diversification and shifts from hermaphroditism to dioecy inAsparagushas been hampered by the lack of robust species tree estimates for the genus. In this study, a genus-wide phylogenomic analysis including 1726 nuclear loci and comprehensive species sampling supports two independent origins of dioecy inAsparagus—first in a widely distributed Eurasian clade, then again in a clade restricted to the Mediterranean Basin. Modeling of ancestral biogeography indicates that both dioecy origins were associated with range expansion out of southern Africa. Our findings also revealed several bursts of diversification across the phylogeny, including an initial radiation in southern Africa that gave rise to 12 major clades in the genus, and more recent radiations that have resulted in paraphyly and polyphyly among closely related species, as expected given active speciation processes. Lastly, we report that the geographic origin of domesticated garden asparagus (Asparagus officinalisL.) was likely in western Asia near the Mediterranean Sea. The presented phylogenomic framework forAsparagusis foundational for ongoing genomic investigations of diversification and functional trait evolution in the genus and contributes to its utility for understanding the origin and early evolution of dioecy and sex chromosomes.

Significance Statement

Asparagusis an important model system for studying dioecy (separate sexes) evolution in plants.Asparagustaxonomy has been challenging, likely due to rapid species diversifications leading to highly variable species with complicated relationships that are impossible to resolve with limited DNA-sequence data. Using phylogenomics and the largest species sampling to date, we show that allAsparaguslineages originated from an initial radiation in southern Africa and that separate range expansions out of southern Africa set the stage for two distinct origins of dioecy inAsparagus. Our findings provide a deeper understanding of species diversification and the role of long-distance dispersals in the evolution of dioecy. This study also illustrates the utility of phylogenomics for elucidating past and present speciation processes.
Evaluation of AlphaFold3 for the fatty acids docking to human fatty acid-binding proteins
Authors: Nam Ki Hyun
Published: July 2024

Human fatty acid-binding proteins (FABPs) are involved in many aspects of lipid metabolism, such as the uptake, transport, and storage of lipophilic molecules, as well as cellular functions. Understanding how FABPs recognize fatty acids (FAs) is crucial for identifying FABP function and applications, such as in inhibitor design or biomarker development. The recently developed AlphaFold3 (AF3) demonstrates significantly higher accuracy than other prediction tools, particularly in predicting protein–ligand interactions with state-of-the-art docking tools. Studies on whether AF3 can be used to identify the FAs of FABP are lacking. To assess the accuracy of FA docking to FABPs using AF3, models of FA docked into FABP generated using AF3 were compared with experimentally determined FA-bound FABP structures. FA ligands in AF3 structures docked reliably into the FA-binding pocket of FABPs; however, the detailed binding configuration of most FA ligands docked into FABPs and the interaction between FA and FABP determined using AF3 and experimentally differed. These results will aid in understanding FA docking to FABPs and other FA-binding proteins using AF3.
History-dependent spiking facilitates efficient encoding of polarization angles in neurons of the central complex
Authors: Rother Lisa , Stöckl Anna , Pfeiffer Keram
Published: July 2024

Many insects use the polarization pattern of the sky for spatial orientation. Since flying insects perform rapid maneuvers, including saccadic yaw turns which alternate with translational flight, they perceive highly dynamic polarization input to their navigation system. The tuning of compass-neurons in the central complex of insects, however, has been mostly investigated with polarized-light stimuli that rotated at slow and constant velocities, and thus were lacking these natural dynamics. Here we investigated the dynamic response properties of compass-neurons, using intracellular recordings in the central complex of bumblebees. We generated naturalistic stimuli by rotating a polarizer either according to a sequence of head orientations that have been reported from freely flying bumblebees, or at constant velocities between 30°/s and 1920°/s, spanning almost the entire range of naturally occurring rotation velocities. We found that compass neurons responded reliably across the entire range of the presented stimuli. In their responses, we observed a dependency on spiking history. We further investigated this dependency using a rate code model taking spiking history into account. Extending the model to a neuronal population with different polarization tuning, which mirrored the neuronal architecture of the central complex, suggests that spiking history has a directly impact on the overall population activity, which has two effects: First, it facilitates faster responses to stimulus changes during highly dynamic flight maneuvers, and increases sensitivity for course deviations during straight flight. Second, population activity during phases of constant polarization input is reduced, which might conserve energy during straight flight.

Significance Statement

Many insects use the pattern of polarized light, which arises from scattering of sunlight, for spatial orientation. Neurons in the central complex, a brain structure, which governs spatial orientation, encode the orientation of the insect’s head with respect to polarized light. To investigate the dynamic properties of these neurons, we recorded intracellularly in the central complex of bumblebees and stimulated with naturalistic polarized-light stimuli. We found that neuronal activity was not only dictated by the angle of polarization, but also by the amount of previous activity. Using a modelling approach we show, that this dependency on spiking history can facilitate faster adjustment of the heading signal and leads to reduced overall activity and therefore reduced energy consumption during straight flight.
The evolutionary fate of Neanderthal DNA in 30,780 admixed genomes with recent African-like ancestry
Authors: Pfennig Aaron , Lachance Joseph
Published: July 2024

Following introgression, Neanderthal DNA was initially purged from non-African genomes, but the evolutionary fate of remaining introgressed DNA has not been explored yet. To fill this gap, we analyzed 30,780 admixed genomes with African-like ancestry from the All of Us research program, in which Neanderthal alleles encountered novel genetic backgrounds during the last 15 generations. Observed amounts of Neanderthal DNA approximately match expectations based on ancestry proportions, suggesting neutral evolution. Nevertheless, we identified genomic regions that have significantly less or more Neanderthal ancestry than expected and are associated with spermatogenesis, innate immunity, and other biological processes. We also identified three novel introgression desert-like regions in recently admixed genomes, whose genetic features are compatible with hybrid incompatibilities and intrinsic negative selection. Overall, we find that much of the remaining Neanderthal DNA in human genomes is not under strong selection, and complex evolutionary dynamics have shaped introgression landscapes in our species.
Chromatin Remodeling by the Histone Methyltransferase SETD2 Drives Lipotoxic Injury in Cardiometabolic Heart Failure with Preserved Ejection Fraction
Authors: Ambrosini Samuele , Costantino Sarah , Mohammed Shafeeq A. , Gorica Era , Herwig Melissa , van Heerebeek Loek , Mengozzi Alessandro , Karsai Gergely , Hornemann Thorsten , Dzemali Omer , Ruschitzka Frank , Hamdani Nazha , Paneni Francesco
Published: July 2024

Background

Cardiometabolic heart failure with preserved ejection fraction (cHFpEF) is highly prevalent and associates with a poor outcome. Pathological gene expression in heart failure is accompanied by changes in active histone marks without major alterations in DNA methylation. Histone 3 trimethylation at lysine 36 (H3k36me3) - a chromatin signature induced by the histone methyltransferase SETD2 - strongly correlates with changes in gene expression in human failing hearts; however, its role is poorly understood. Here we investigate the role of SETD2 in cHFpEF.

Methods

Mice with cardiomyocyte-specific deletion of SETD2 (c-SETD2-/-) were generated and subjected to high fat diet feeding and L-NAME treatment for 15 weeks to induce cHFpEF. Cardiac function and exercise tolerance were assessed by echocardiography and Treadmill exhaustion test. Chromatin immunoprecipitation assays (ChIP) were performed to investigate SETD2/H3k36me3 enrichment on gene promoters. SETD2 gain- and loss-of-function experiments were performed in cultured cardiomyocytes (CMs) exposed to palmitic acid (PA). SETD2 expression was also investigated in left ventricular (LV) myocardial specimens from patients with cHFpEF and control donors.

Results

SETD2 was upregulated in cHFpEF mouse hearts and its chromatin mark H3k36me3 was enriched on the promoter of sterol regulatory element-binding transcription factor 1 (SREBP1) gene. SETD2 activation in cHFpEF led to SREBP1 upregulation, triglyceride accumulation and lipotoxic damage. Of note, cardiomyocyte-specific deletion of SETD2 in mice prevented HFpEF-related hypertrophy, diastolic dysfunction and lung congestion while improving exercise tolerance. SETD2 deletion blunted H3K36me3 enrichment on SREBP1 promoter thus leading to a marked rewiring of the cardiac lipidome and restoration of autophagic flux. SETD2 depletion in PA-treated CMs prevented SREBP1 upregulation, whereas SETD2 overexpression recapitulated lipotoxic damage. Finally, SETD2 was upregulated in LV specimens from cHFpEF patients and its pharmacological inhibition by EZM0414 attenuated CM stiffness.

Conclusions

Therapeutic modulation of SETD2/H3k36me3 axis might prevent lipotoxic injury and cardiac dysfunction in cHFpEF.
Engineering anti-amyloid antibodies with transferrin receptor targeting improves brain biodistribution and mitigates ARIA
Authors: Pizzo Michelle E. , Plowey Edward D. , Khoury Nathalie , Kwan Wanda , Abettan Jordan , DeVos Sarah L. , Discenza Claire B. , Earr Timothy , Joy David , Lye-Barthel Ming , Roche Elysia , Chan Darren , Dugas Jason C. , Gadkar Kapil , Meisner René , Sebalusky Jennifer , Amaral Ana Claudia Silva , Becerra Isabel , Chau Roni , Chow Johann , Clemens Allisa J. , Dennis Mark S. , Duque Joseph , Fusaro Laura , Getz Jennifer A. , Kariolis Mihalis S. , Kim Do Jin , Leung Amy Wing-Sze , Nguyen Hoang N. , Thomsen Elliot R. , Sanchez Pascal E. , Shan Lu , Silverman Adam P. , Solanoy Hilda , Tong Raymond , Calvert Meredith E. , Watts Ryan J. , Thorne Robert G. , Weinreb Paul H. , Walsh Dominic M. , Lewcock Joseph , Bussiere Thierry , Zuchero Y. Joy Yu
Published: July 2024

Although the first generation of immunotherapies for Alzheimer’s disease (AD) are now clinically approved, amyloid-related imaging abnormalities (ARIA) remain a major safety problem for this class of drugs. Here, we report an antibody transport vehicle (ATV) targeting the transferrin receptor (TfR) for brain delivery of amyloid beta (Aý) antibodies that significantly reduced ARIA-like lesions and improved plaque target engagement in a mouse model of amyloid deposition. Asymmetrical Fc mutations (ATVcisLALA) allowed the molecule to selectively retain effector function only when bound to Aý while mitigating TfR-related hematology liabilities. Mice treated with ATVcisLALA:Aý exhibited broad brain parenchymal antibody distribution; in contrast, anti-Aý IgG was highly enriched at arterial perivascular spaces where vascular Aý localizes and likely plays a role in induction of ARIA. Importantly, ATVcisLALA: Aý almost completely eliminated ARIA-like lesions and vascular inflammation associated with anti-Aý treatment. Taken together, ATVcisLALAhas the potential to significantly improve both safety and efficacy of Aý immunotherapy through enhanced biodistribution mediated by transport across the blood-brain barrier.
Contrast-dependent response modulation in convolutional neural networks captures behavioral and neural signatures of visual adaptation
Authors: Brands Amber Marijn , Oz Zilan , Vukšić Nikolina , Ortiz Paulo , Groen Iris Isabelle Anna
Published: July 2024

Human perception remains robust under challenging viewing conditions. Robust perception is thought to be facilitated by nonlinear response properties, including temporal adaptation (reduced responses to re-peated stimuli) and contrast gain (shift in the contrast response function with pre-exposure to a stimulus). Temporal adaptation and contrast gain have both been shown to aid object recognition, however, their joint effect on perceptual and neural responses remains unclear. Here, we collected behavioural measurements and electrocorticography (EEG) data while human participants (both sexes) classified objects embedded within temporally repeated noise patterns, whereby object contrast was varied. Our findings reveal an in-teraction effect, with increased categorization performance as a result of temporal adaptation for higher but not lower contrast stimuli. This increase in behavioral performance after adaptation is associated with more pronounced contrast-dependent modulation of evoked neural responses, as well as better decoding of object information from EEG activity. To elucidate the neural computations underlying these effects, we endowed deep convolutional neural networks (DCNN) with various temporal adaptation mechanisms, including intrinsic suppression and temporal divisive normalisation. We demonstrate that incorporating a biologically-inspired contrast response function to modify temporal adaptation helps DCNNs to accurately capture human behaviour and neural activation profiles. Moreover, we find that networks with multiplicative temporal adaptation mechanisms, such as divisive normalization, show higher robustness against spatial shifts in the inputs compared to DCNNs employing additive mechanisms. Overall, we reveal how interaction effects between nonlinear response properties influence human perception in challenging viewing contexts and investigate potential computations that mediate these effects.

Significance statement

Humans are able to perceive the environment even when viewing conditions are suboptimal. This robust perception has been linked to nonlinear neural processing of incoming visual information. Here, we examine the joint impact of two neural response properties, temporal adaptation and contrast gain, during object recognition, demonstrating interaction effects on categorization performance and in evoked neural responses. Using convolutional neural networks, we investigate various temporal adaptation mechanisms mediating the neural responses and perception, demonstrating that introducing contrast-dependent modulation of the unit activations captures human behaviour and neural object representations. Our findings shed light on how neural response properties give rise to robust perception and offer a framework to study the underlying neural dynamics and their impact on perception.
Plasma proteome profiling for AKI biomarker candidates associated with first-line ART in people living with HIV in South Africa
Authors: Mokoena Rethabile J , Nabeemeeah Firdaus , Variava Ebrahim , Fanucchi Sylvia , Martinson Neil , Govender Ireshyn S , Naicker Previn
Published: July 2024

With the highest global burden of HIV, South Africa initiates HIV treatment using first line antiretroviral therapy (AR ) regimens in newly diagnosed patients. Antiretroviral (ARV) associated nephrotoxicity has been observed in 10% of South African patients newly receiving first line AR , as well as in patients who have extensively received TDF-based ART regimens, and this can progress to acute kidney injury (A I). o identify potential biomarkers that will improve the detection of ARV associated nephrotoxicity, proteomic analysis was performed using the sequential window acquisition of all theoretical mass spectra (SWATH MS) data acquisition method on the plasma of the case group (AKI) and the control group (non AKI). Data are available via ProteomeXchange with identifier PXD054218. Evaluation of the results identified thirty four proteins that showed a significant change in abundance, with three proteins showing increased abundance, while thirty one proteins showed decreased abundance between the A I and non A I groups. Machine learning was also used to evaluate the results and showed twenty ranked proteins that contributed to distinguishing between the AKI and non AKI groups. The majority of the proteins of significant differential abundance and those ranked by the machine learning model participate in enriched biological processes that correspond to known pathophysiological and cellular mechanisms that contribute to AKI, suggesting that those proteins can serve as potential biomarkers to be further verified and validated for AKI diagnosis. Comparison of the plasma and previously generated urinary proteome profiles showed five proteins with significant differences in abundance that overlapped both proteomes providing evidence for the renal physiological dynamics of these proteins in renal injury and disease. Significance: Improving the detection of ARV associated nephrotoxicity is challenging because current serum creatinine (srCr) based equations used to estimate the glomerular filtration rate (eGFR) for assessing kidney function have been reported to overestimate the eGFR in the South African population and changes in srCr measurements also reflect a delayed response to the initial structural injury of the kidney. his hinders the timeous detection of ARV associated nephrotoxicity which can lead to irreversible renal damage and can compromise the continuation of treatment in P HIV, thus emphasising the need to introduce novel AI biomarkers to mitigate ARV associated nephrotoxicity in at risk P HIV in South Africa.
CD6 Regulates CD4 T Follicular Helper Cell Differentiation and Humoral Immunity During Murine Coronavirus Infection
Authors: Cardani-Boulton Amber , Lin Feng , Bergmann Cornelia C
Published: July 2024

During activation the T cell transmembrane receptor CD6 becomes incorporated into the T cell immunological synapse where it can exert both co-stimulatory and co-inhibitory functions. Given the ability of CD6 to carry out opposing functions, this study sought to determine how CD6 regulates early T cell activation in response to viral infection. Infection of CD6 deficient mice with a neurotropic murine coronavirus resulted in greater activation and expansion of CD4 T cells in the draining lymph nodes. Further analysis demonstrated that there was also preferential differentiation of CD4 T cells into T follicular helper cells, resulting in accelerated germinal center responses and emergence of high affinity virus specific antibodies. Given that CD6 conversely supports CD4 T cell activation in many autoimmune models, we probed potential mechanisms of CD6 mediated suppression of CD4 T cell activation during viral infection. Analysis of CD6 binding proteins revealed that infection induced upregulation ofUbash3a,a negative regulator of T cell receptor signaling, was hindered in CD6 deficient lymph nodes. Consistent with greater T cell activation and reduced UBASH3a activity, the T cell receptor signal strength was intensified in CD6 deficient CD4 T cells. These results reveal a novel immunoregulatory role for CD6 in limiting CD4 T cell activation and deterring CD4 T follicular helper cell differentiation, thereby attenuating antiviral humoral immunity.

Importance

CD6 monoclonal blocking antibodies are being therapeutically administered to inhibit T cell activation in autoimmune disorders. However, the multifaceted nature of CD6 allows for multiple and even opposing functions under different circumstances of T cell activation. We therefore sought to characterize how CD6 regulates T cell activation in the context viral infections using anin vivomurine coronavirus model. In contrast to its role in autoimmunity, but consistent with its function in the presence of superantigens, we found that CD6 deficiency enhances CD4 T cell activation and CD4 T cell help to germinal center dependent antiviral humoral responses. Finally, we provide evidence that CD6 regulates transcription of its intracellular binding partner UBASH3a, which suppresses T cell receptor signaling and consequently T cell activation. These findings highlight the context dependent flexibility of CD6 in regulatingin vivoadaptive immune responses, which may be targeted to enhance anti-viral immunity.
MitoMAMMAL: a genome scale model of mammalian mitochondria predicts cardiac and BAT metabolism
Authors: Chapman Stephen P. , Brunet Theo , Mourier Arnaud , Habermann Bianca H.
Published: July 2024

Mitochondria perform several essential functions in order to maintain cellular homeostasis and mitochondrial metabolism is inherently flexible to allow correct function in a wide range of tissues. Dysregulated mitochondrial metabolism can therefore affect different tissues in different ways which presents experimental challenges in understanding the pathology of mitochondrial diseases. System-level metabolic modelling is therefore useful in gaining in-depth insights into tissue-specific mitochondrial metabolism, yet despite the mouse being a common model organism used in research, there is currently no mouse specific mitochondrial metabolic model available. In this work, building upon the similarity between human and mouse mitochondrial metabolism, we have created mitoMammal, a genome-scale metabolic model that contains human and mouse specific gene-product reaction rules. MitoMammal is therefore able to model mouse and human mitochondrial metabolism. To demonstrate this feature, using an adapted E-Flux2 algorithm, we first integrated proteomic data extracted from mitochondria of isolated mouse cardiomyocytes and mouse brown adipocyte tissue. We then integrated transcriptomic data fromin vitrodifferentiated human brown adipose cells and modelled the context specific metabolism using flux balance analysis. In all three simulations, mitoMammal made mostly accurate, and some novel predictions relating to energy metabolism in the context of cardiomyocytes and brown adipocytes. This demonstrates its usefulness in research relating to cardiac disease and diabetes in both mouse and human contexts.
Dynamics of influenza transmission in vampire bats revealed by longitudinal monitoring and a large-scale anthropogenic perturbation
Authors: Griffiths Megan E , Broos Alice , Morales Juan , Tu I-Ting , Bergner Laura , Behdenna Abdelkader , Valderrama William , Tello Carlos , Carrera Jorge E , Recuenco Sergio , Streicker Daniel G , Viana Mafalda
Published: July 2024

Interrupting pathogen transmission between species is a priority strategy to mitigate zoonotic threats. However, avoiding counterproductive interventions requires knowing animal reservoirs of infection and the dynamics of transmission within them, neither of which are easily ascertained from the cross-sectional surveys which currently dominate investigations into newly discovered viruses. We used biobanked sera and metagenomic data to reconstruct the transmission of recently discovered bat-associated influenza virus (BIV) over 12 years in three zones of Peru. Mechanistic models fit under a Bayesian framework, which enabled joint inference from serological and molecular data, showed that common vampire bats maintain BIV independently of the currently assumed fruit bat reservoir through immune waning and seasonal transmission pulses. A large-scale vampire bat cull targeting rabies incidentally halved BIV transmission, confirming vampire bats as maintenance hosts. Our results show how combining field studies, perturbation responses and multi-data type models can elucidate pathogen dynamics in nature and reveal pathogen-dependent effects of interventions.
A fast and simple approach tok-mer decomposition
Authors: Kunzmann Patrick
Published: July 2024

Alignment searches are fast heuristic methods to identify similar regions between two sequences. This group of algorithms is ubiquitously used in a myriad of software to find homologous sequences or to map sequence reads to genomes. Often the first step in alignment searches isk-mer decomposition: listing all overlapping subsequences of lengthk. This article presents a simple integer representation ofk-mers and shows how a sequence can be quickly decomposed intok-mers in constant time with respect tok.
Molecular mimicry of a pathogen virulence target by a plant immune receptor
Authors: Gómez De La Cruz Diana , Zdrzałek Rafał , Banfield Mark J. , Talbot Nicholas J. , Moscou Matthew J.
Published: July 2024

Plants and animals respond to pathogen attack by mounting innate immune responses that require intracellular nucleotide binding leucine-rich repeat (NLR) proteins. These immune receptors detect pathogen infection by sensing virulence effector proteins. However, the mechanisms by which receptors evolve new recognition specificities remain poorly understood. Here we report that a plant NLR has evolved the capacity to bind to a pathogen effector by acting as a molecular mimic of a virulence target of the effector, thereby triggering an immune response. The barley NLR Mildew Locus A 3 (MLA3) confers resistance to the blast fungusMagnaporthe oryzaeby recognizing the effector Pwl2. Using structural analysis, we show that MLA3 has acquired the capacity to bind and respond to Pwl2 through molecular mimicry of the effector host target HIPP43. We demonstrate that the amino acids at the binding interface of MLA3 and Pwl2 are highly conserved in interface of HIPP43 with Pwl2, and are required to trigger an immune response. We used this discovery to bioengineer SR50—an MLA ortholog in rye that confers resistance to wheat stem rust—by introducing the Pwl2 binding interface of MLA3. This chimeric receptor has dual recognition activities, binding and responding to effectors from two major cereal pathogens. Collectively, these results provide evidence that plant immune receptors have evolved sophisticated mimicry strategies to counteract pathogen attack.
Activation of the influenza B M2 proton channel (BM2)
Authors: Yue Zhi , Wu Jiangbo , Teng Da , Wang Zhi , Voth Gregory A
Published: July 2024

Influenza B viruses have co-circulated during most seasonal flu epidemics and can cause significant human morbidity and mortality due to their rapid mutation, emerging drug resistance, and severe impact on vulnerable populations. The influenza B M2 proton channel (BM2) plays an essential role in viral replication, but the mechanisms behind its symmetric proton conductance and the involvement of a second histidine (His27) cluster remain unclear. Here we perform the membrane- enabled continuous constant-pH molecular dynamics simulations on wildtype BM2 and a key H27A mutant to explore its pH-dependent conformational switch. Simulations capture the activation as the first histidine (His19) protonates and reveal the transition at lower pH values compared to AM2 is a result of electrostatic repulsions between His19 and pre-protonated His27. Crucially, we provide an atomic-level understanding of the symmetric proton conduction by identifying pre-activating channel hydration in the C-terminal portion. This research advances our understanding of the function of BM2 function and lays the groundwork for further chemically reactive modeling of the explicit proton transport process as well as possible anti-flu drug design efforts.
A second X chromosome improves cognition in aging male and female mice
Authors: Marino Francesca , Wang Dan , Merrihew Gennifer E. , MacCoss Michael J. , Dubal Dena B.
Published: July 2024

Women show resilience to cognitive aging, in the absence of dementia, in many populations. To dissect sex differences, we utilized the FCG and XY*mouse models. Female gonads and sex chromosomes improved cognition in aging mice of both sexes. Further, presence of a second X in male and female mice conferred cognitive resilience while its absence in females blocked it. In the hippocampal proteome of aging female mice, the second X increased proteins involved in synaptogenesis signaling – a potential pathway to improved cognition.
Identifying an
X(3872)
tetraquark state versus a molecular state by formation time, velocity, and temperature in relativistic nuclear collisions
Authors: She Zhi-Lei , Lei An-Ke , Yan Yu-Liang , Zhou Dai-Mei , Zhang Wen-Chao , Zheng Hua , Zheng Liang , Xie Yi-Long , Chen Gang , Sa Ben-Hao
Published: July 2024

The production of exotic hadron X(3872) in pp collisions at s=2.76TeV is investigated by the parton and hadron cascade model PACIAE in this work. In the simulation the final partonic state (quark matter, QM) and the final hadronic state (hadron matter, HM) are continuously processed and recorded. The X(3872) compact tetraquark state and loose molecular state are, respectively, coalesced and recombined in the QM and HM with the quantum statistical mechanics inspired dynamically constrained phase-space coalescence model. The formation time, velocity, and temperature of QM (tetraquark state) and HM (molecular state) are proposed as identifying criteria between the two states. Our results in transverse momentum spectrum and rapidity distribution, etc. show a significant discrepancy between the two states and confirm that they are also valuable criteria identifying the X(3872) compact tetraquark state or molecular state.

Published by the American Physical Society
2024
Dual chiral density wave induced oscillating Casimir effect
Authors: Fujii Daisuke , Nakayama Katsumasa , Suzuki Kei
Published: July 2024

The Casimir effect is known to be induced from photon fields confined by a small volume, and also its fermionic counterpart has been predicted in a wide range of quantum systems. Here, we investigate what types of Casimir effects can occur from quark fields in dense and thin quark matter. In particular, in the dual chiral density wave, which is a possible ground state of dense quark matter, we find that the Casimir energy oscillates as a function of the thickness of matter. This oscillating Casimir effect is regarded as an analog of that in Weyl semimetals and is attributed to the Weyl points in the momentum space of quark fields. In addition, we show that an oscillation is also induced from the quark Fermi sea, and the total Casimir energy is composed of multiple oscillations.

Published by the American Physical Society
2024
Collapse of neutrino wave functions under Penrose gravitational reduction
Authors: Jones B. J. P. , Seidel O. H.
Published: July 2024

Models of spontaneous wave function collapse have been postulated to address the measurement problem in quantum mechanics. Their primary function is to convert coherent quantum superpositions into incoherent ones, with the result that macroscopic objects cannot be placed into widely separated superpositions for observably prolonged times. Many of these processes will also lead to loss of coherence in neutrino oscillations, producing observable signatures in the flavor profile of neutrinos at long travel distances. The majority of studies of neutrino oscillation coherence to date have focused on variants of the continuous state localization model, whereby an effective decoherence strength parameter is used to model the rate of coherence loss with an assumed energy dependence. Another class of collapse models that have been proposed posit connections to the configuration of gravitational field accompanying the mass distribution associated with each wave function that is in the superposition. A particularly interesting and prescriptive model is Penrose’s description of gravitational collapse which proposes a decoherence time τ determined through Egτ∼ℏ, where Eg is a calculable function of the Newtonian gravitational potential. Here we explore application of the Penrose collapse model to neutrino oscillations, reinterpreting previous experimental limits on neutrino decoherence in terms of this model. We identify effects associated with both spatial collapse and momentum diffusion, finding that the latter is ruled out in data from the IceCube South Pole Neutrino Observatory so long as the neutrino wave packet width at production is σν,x≤2×10−12  m.

Published by the American Physical Society
2024
BarkB2B: growing the business-to-business (B2B) marketing sector
Authors: El Kolaly Hoda , Khatcherian Arpi
Published: July 2024

Learning outcomes

After completion of the case study, students will be able to enumerate the unique characteristics of business-to-business (B2B) versus business-to-consumer marketing, explore strategic positioning and how niche marketing can create a competitive advantage, deduce the significance of core values in corporate culture and decision-making, explore innovative partnership and talent acquisition models, infer the role of educational marketing in sectors where clients are not fully aware of their needs and apply strategic decision-making to balance short- and long-term goals in terms of profitability and growth.

Case overview/synopsis

This case study tells the story of BarkB2B, a boutique marketing firm specialized exclusively in B2B marketing. Founded in Egypt in 2018, BarkB2B focused on creating long-lasting partnerships with clients in industries such as IT, logistics, construction and renewable energy. The case explores the critical aspects of BarkB2B’s business model and offers a comprehensive view of real-world challenges and opportunities in the B2B marketing landscape. It helps learners understand strategic positioning, core values in decision-making, innovative partnership-based business models, the role of educational marketing and the complexities associated with growth. It concludes by highlighting the dilemma faced by BarkB2B’s founder and managing director Naela Sakr as she reflects on the challenge of maintaining the company’s positioning while achieving greater profitability and growth.

Complexity academic level

The case study is intended for undergraduate and graduate students in marketing, strategic marketing, consumer behavior and entrepreneurship courses. It is also beneficial for marketing professionals, entrepreneurs, corporate training and executive education programs.

Supplementary materials

Teaching notes are available for educators only.

Subject code

CSS 8: Marketing.
Assessing perceived usability of Google Drive using cloud usability model: a mixed method study
Authors: Taqi Farwa , Arshad Alia , Batool Syeda Hina
Published: July 2024

Purpose

This study aims to evaluate the usability of Google Drive (GD) in addition to measuring the effectiveness of GD and the challenges faced while using this cloud storage application among public library users of Lahore.

Design/methodology/approach

The study adopted a sequential explanatory mixed method design comprising the quantitative (QUAN) and qualitative (QUAL) parts. For the QUAN phase, a questionnaire survey was conducted among 384 users of public libraries through purposive sampling. For the QUAL phase, the think aloud technique was performed on several tasks during experiments and verbalized their thoughts and experiences while interacting with the system. The cloud usability model (CUM) was used to measure the “usability” of GD.

Findings

Findings indicated that most users were satisfied with GD's obvious features and inherent functions. QUAL results indicated that respondents did most tasks easily, whereas only some could complete the task.

Research limitations/implications

The study is valuable as it is the first time used CUM to measure the perceived usability of GD. Second, the study used a mixed method study to get insights into perceived usability, effectiveness and challenges while using GD. The findings might be helpful for cloud support teams, including GD, as they can enhance certain features of usability, which lead to increased usage among users.

Originality/value

This research work is based on MPhil thesis.
Investigating the mediating role of self-efficacy between digital leadership capability, intercultural competence, and employability among working undergraduates
Authors: Zhan Hui , Cheng Kin Meng , Wijaya Lianna , Zhang Songcun
Published: July 2024

Purpose

Utilizing the Social Cognitive Theory framework, this research aims to illuminate how self-efficacy acts as a mediating factor, enhancing employability among working university students by fostering essential capabilities in digital leadership and intercultural competence.

Design/methodology/approach

Quantitative study with 206 working undergraduates from an Indonesian university. Questionnaires and structural equation modeling (SEM) with SPSS and SmartPLS were used.

Findings

Findings showed that working undergraduate students possess a high level of digital leadership capability and intercultural competence and tend to display increased confidence in their ability to perform challenging tasks and attain anticipated outcomes, thereby enhancing their employability. The integration of these skills, coupled with a solid self-efficacy belief, emerges as a powerful combination in the modern employment landscape in the digital transformation and Artificial Intelligence age.

Research limitations/implications

This research is conducted in one university in Indonesia, potentially limiting its generalizability. Future studies could expand its regions to multiple universities across different countries for a more comprehensive implication.

Practical implications

This research answered the call for strategies from the university level on enhancing the development of essential competencies for working undergraduate students’ employability. It further highlights the necessity for shaping the curriculum to prioritize digital leadership capability, intercultural competence, and the cultivation of self-efficacy among working students.

Social implications

This insight of the research has profound social implications, indicating that educational institutions must adapt their curricula to prioritize these competencies. By doing so, universities can better prepare students to navigate the complexities of the modern workplace, thereby contributing to a workforce that is not only technologically proficient but also culturally adept and resilient in the face of challenges. This adaptation is essential for fostering a generation of graduates who are well-equipped to contribute positively to a diverse and rapidly evolving labor market, ultimately benefiting both the individuals and the wider society by promoting economic development and cultural understanding.

Originality/value

Adopting a quantitative approach, this research offers a data-driven lens of employability determinants, deepening the understanding of how intertwined competencies shape employment outcomes in the AI age.
The role of institutional factors in shaping the relationship between economic policy uncertainty and energy consumption in Gulf countries: an empirical analysis
Authors: Hnainia Hadil , Mensi Sami
Published: July 2024

Purpose

This research investigates the complex relationship between economic policy uncertainty (EPU), energy consumption and institutional factors in the Gulf region. The purpose of this study is to examine how institutional factors moderate the impact of EPU on energy consumption in Gulf countries.

Design/methodology/approach

This paper uses the dynamic panel autoregressive distributed lag (PARDL) method, over a period stretching from 1996 to 2021 in the Gulf countries.

Findings

The results show that, only in the long term, EPU has a positive and significant impact on energy consumption, suggesting that increased EPU leads to increased energy use. Furthermore, this study found that, only in the long term, government effectiveness and regulatory quality have positive and significant effect on energy consumption. Accordingly, the two institutional factors play a moderating role in the EPU−energy consumption nexus.

Research limitations/implications

This study highlights the importance of considering the time dimension when formulating energy and economic policies in Gulf countries. Policymakers should take into consideration the nature of these relationships to make informed decisions that promote energy efficiency and economic stability in the region.

Originality/value

To the best of the authors’ knowledge, this is the first study examining the relationship between EPU and energy consumption in the Gulf countries while incorporating the role of institutional factors as potential mediators.
How nostalgia in advertising increases brand love: a cross-country study
Authors: Grappi Silvia , Pauwels Veronique , Pedeliento Giuseppe , Zarantonello Lia
Published: July 2024

Purpose

This paper aims to investigate the extent to which nostalgic advertising can foster brand love. It examines the effects of two common forms of nostalgia in advertising – that is, personal and historical nostalgia – on consumers’ love towards a brand in both a developed (the UK) and a developing country (India).

Design/methodology/approach

A pre-test and post-test quasi-experimental study was conducted with two representative samples of consumers (i.e. 277 British and 255 Indian). Respondents were randomly exposed to one ad evoking either personal or historical nostalgia, or a non-nostalgic ad.

Findings

The results indicate that the use of nostalgia in advertising increases brand love in both countries. However, the effectiveness of each type of nostalgia varies depending on the country considered. In the UK, personal nostalgia increases brand love more than historical nostalgia, whereas, in India, historical nostalgia was found to be more significantly related to brand love than personal nostalgia.

Practical implications

The primary implication for marketers is to consider nostalgic advertising as a critical lever to building longer-term value for a brand (i.e. brand love) whilst being mindful of the country-specific differences regarding how such a lever should be executed to achieve effectiveness be effective.

Originality/value

The paper contributes to the advancement of the brand love literature by clarifying whether, and under what circumstances, the use of specific types of nostalgia in advertising increases consumers’ love towards a brand.
Toward a satisfactory sustainable education for international students: a qualitative framework for international accounting students
Authors: Arianpoor Arash , Dheyab Al-Ani Saba Sabah , Khayoon Hameed Mohsin
Published: July 2024

Purpose

This study aims to provide a qualitative framework for satisfactory sustainable education for international accounting students using a meta-synthetic approach.

Design/methodology/approach

To determine the components and indicators of satisfactory sustainable education for international accounting students, a meta-synthesis allows for the attainment of the objectives of study. In the first phase of study, international related literature was reviewed (n = 2,176). After several screenings for measuring the quality of the related literature including Critical Appraisals Skills Program (CASP), the total number of selected papers was 48, and 2,128 were excluded.

Findings

The present research proposed a comprehensive conceptual model for sustainable education and international accounting students’ satisfaction, with seven components and 63 indicators. To assess the credibility of phases, the indicators were presented to five experts independently. The reliability of the proposed conceptual model was tested using Cohen’s Kappa coefficient and analyzed in SPSS. Kappa’s coefficient showed that the agreement level was high and the reliability was high too.

Originality/value

Sustainable education and student satisfaction are crucial for maintaining a competitive international education market. There are ongoing debates about accounting education, particularly accreditation challenges and the need for clear regulations on academic interaction with practice. Accounting education has also been criticized for being outdated, promoting surface-level learning and neglecting the development of broader skills in university graduates. Therefore, it is important to understand sustainable education for international accounting students. The present study aims to identify the aspects of accounting educational services that international accounting students perceive important for increasing satisfaction. This research provides empirical evidence and suggests potential avenues for future research in other countries.
Scrutiny of Police Institutions and the Spectre of Culture
Authors: Feilzer Martina , Loftus Bethan
Published: July 2024

This article revisits the concept of police culture and its explanatory value in understanding the recent scandals that have rocked policing in England and Wales. It focusses on concerns around the prevalence of sexism and violence against women and girls (VAWG) within policing and explores whether an increase in the diversity of police officers has pushed aspects of police culture into specific specialist and less visible areas of policing. The article suggests that any attempts at substantive police reform need to consider radical organisational and structural change, including a new narrative for British policing. Such a narrative needs political and social support and will require wider engagement beyond internally focussed police discussions.
The point of no return: Crisis management lessons from US adults' infectious disease risk (IDR) perception and response to the Flu‐and‐COVID dual threat
Authors: Seo Youngji , Choi Sung In , Ko Youngjee , Jin Yan
Published: July 2024

Crisis learning is essential for improving crisis management. Looking back at how public health crises were managed, crisis scholars and practitioners can garner important future crisis readiness insight in managing critical risks and crises threatening public health and safety. Among existing crisis research examining infectious disease risks (IDRs) and IDR‐triggered health crises, few studies have examined how co‐existing particular infectious diseases influence individuals' risk perception and crisis responses. To address this gap, the current study provides lessons learned from an online survey, using a nationally representative US adult sample (N = 517), conducted during the early stages of the Coronavirus [COVID‐19] outbreak, before the World Health Organization (WHO) declared the COVID‐19 global pandemic. The unique timing of the online survey allows us to examine: (1) how US adults perceived individual health risks associated with COVID‐19 and influenza [the flu], two infectious diseases concurrently discussed and compared by the news media and health experts; and (2) how perceived IDR influences their subsequent behavioral response. Key findings include, first, that the less novel IDR (i.e., the flu) led to higher perceived susceptibility, while the more novel IDR (i.e., COVID‐19), at the point of data collection, led to higher perceived severity. Second, IDR susceptibility and severity predicted intention to preventive action when confronted by the flu or COVID‐19. Third, individuals' trust in the government moderated risk response by IDR type. These findings have theoretical and practical implications for effective IDR communication in the process of ongoing public crisis management.