bluuebunny/crossref_metadata_2025 huggingface dataset:
Integrative transcriptomics and electrophysiological profiling of hiPSC-derived neurons identifies novel druggable pathways in Koolen-de Vries Syndrome
Authors: Verboven A.H.A. , Puvogel S. , Kolsters N. , Latour B. , Linda K. , Lewerissa E.I. , Mijdam R. , Dyke E. , Duineveld D. , Zoodsma M. , Claassen W.J.J. , Oudakker A. , Schoenmaker C. , Koolen D.A. , de Vries B.B.A. , ’t Hoen P.A.C. , Kasri N. Nadif
Published: August 2024

Koolen-de Vries Syndrome (KdVS) is a neurodevelopmental disorder (NDD) with no treatment options due to a lack of understanding of its underlying pathophysiology. To investigate neuronal activity in KdVS, human induced pluripotent stem cell (hiPSC)-derived neurons from KdVS and control subjects were cultured on microelectrode arrays (MEAs). Our study identified reduced network burst rates, indicating disorganized network activity in KdVS neurons. To bridge molecular and functional aspects of the syndrome, we developed an experimental framework, MEA-seq, that integrates network activity measurements with high-throughput transcriptome profiling. This approach identified a negative correlation between the expression of the NDD-associated geneCLCN4and the network burst rate. Consequently, knockdown ofCLCN4in KdVS neurons restored the activity to control level, confirming a causal relationship between increasedCLCN4expression and reduced network burst rate. Additionally, we identified a positive correlation between mitochondrial gene expression and the network burst rate, and identified impaired mitochondrial function in KdVS hiPSC-derived neurons. The transcriptomic signature of KdVS neurons was then used for computational screening against drug perturbation signatures of the LINCS Consortium database, predicting other drug targets and compounds capable of reversing the expression of affected genes in KdVS neurons. We selected 10 compounds for experimental validation, identifying the antioxidant phloretin and the Rho-kinase inhibitor fasudil as potential candidates for restoring the network activity dysfunction in KdVS. We conclude that the integrative molecular and electrophysiological of hiPSC-derived neurons with MEA-seq has excellent potential for identifying novel drugs and druggable pathways for KdVS and other NDDs.
Metagenomic analyses of the plastisphere reveals a common functional potential across oceans
Authors: Lips Stefan , Schmitt-Jansen Mechthild , Borchert Erik
Published: August 2024

Trillions of plastic particles have accumulated in the oceans, covered by microbial biofilms (termed the 'plastisphere') whose functional potential remains unexplored. We evaluated genome-resolved bacterial metagenomes of the plastisphere from the North Atlantic and North Pacific garbage patches and compared their structure and functional potential to ambient plankton. Our data revealed a characteristic genetic potential of the plastisphere with functionally equivalent taxonomic units across both oceans. We found fewer coding genes, smaller genome sizes and lower GC-content in plankton in comparison to the plastisphere, despite residing in the same environment, reflecting a greater nutrient demand in the plastisphere. A functional gene analysis confirmed that the plastisphere consists of microorganisms with a higher potential to control their nutrient supply, metabolize a wider range of carbon sources, attenuate free radicals and use alternative energy sources like anoxygenic photosynthesis. Our results suggest that the overriding factor for the high functional similarity of the plastisphere in both oceans is the habitat for biofilm formation with the potential to support mutualism and nutrient sharing making genomic streamlining as found in plankton, unnecessary. Consequently, increasing plastic pollution promotes the expansion of new functional units within oligotrophic oceans, with the potential to impact biogeochemical cycles.
Emergent metabolic interactions in resistance toClostridioides difficileinvasion
Authors: Ambat Achuthan , van den Berg Naomi Iris , Zorrilla Francisco , Menon Shruti , Maji Abhijit , Basile Arianna , Ghimire Sudeep , Kalmar Lajos , Patil Kiran R. , Scaria Joy
Published: August 2024

Commensal gut bacteria are key contributors to the resilience against pathogen invasion. This is exemplified by the success of fecal microbiota transplantation in treating recurrentClostridioides difficileinfection. Yet, characteristics of communities that can confer colonization resistance and the underlying mechanisms remain largely unknown. Here we use a synthetic community of 14 commensal gut bacteria to uncover inter-species interactions and metabolic pathways underpinning the emergent resilience againstC. difficileinvasion. We challenged this synthetic community as well as fecal-matter-derived communities with antibiotic treatment andC. difficilein a continuous flow bioreactor. Using generalized Lotka-Volterra and genome-scale metabolic modelling, we identified interactions betweenEscherichia coliandBacteroides/Phocaeicolasp. as key to the pathogen’s suppression. Metabolomics analysis further revealed that fructooligosaccharide metabolism, vitamin B3 biosynthesis, and competition for Stickland metabolism precursors contribute to suppression. Analysis of metagenomics data from patient cohorts and clinical trials attested thein vivorelevance of the identified metabolic pathways and the ratio betweenBacteroidesandEscherichiain successful colonization resistance. The latter was found to be a much stronger discriminator than commonly used alpha diversity metrics. Our study uncovers emergent microbial interactions in pathogen resistance with implications for rational design of bacteriotherapies.
Palatability of Insecticides and Protein in Sugar Solutions to Argentine Ants
Authors: Wagner Thomas , Vorjans Moana , Garsi Elias , Werneke Cosmina , Czaczkes Tomer J.
Published: August 2024

Invasive ant species likeLinepithema humilecause significant ecological and economic harm, making effective control strategies essential. Insecticide baits are currently the most effective approach for controlling ants. Therefore, quantifying how palatable or unpalatable baits, bait additives, or toxicants are, is critical for developing effective control methods. It has recently been demonstrated that in the comparative evaluation of foods, animals that are aware of both a test food and a comparator food exhibit greatly increased sensitivity when detecting the unpalatability of liquid baits. Here, we deploy a newly developed comparative evaluation methodology to examine the palatability toL. humileworkers of three toxicants used in invasive ant control: Fipronil, spinosad, and imidacloprid, as well as egg white protein.

Ants showed no significant preference between pure sucrose and sucrose-toxicant solutions, indicating that they either cannot detect the toxicants or that they do not find them distasteful. Survival tests confirmed that the toxicant concentrations used were lethal, with a survival rate of 50% or below after 72 hours. However, ants found egg protein additive unpalatable, significantly preferring pure sucrose to a sucrose-egg protein mix.

These findings confirm that three major toxicants are suitable for use in baits, and that reported abandonment or avoidance of toxic baits is not due to the unpalatability of these toxicants. However, the addition of egg protein to sucrose baits, even at ratios which optimise colony growth, is likely counterproductive. Future research should investigate the relative preference of invasive ants for various bait matrixes over naturally available food, ensuring more effective pest management strategies.
Patients with peripheral artery disease demonstrate altered expression of soluble and membrane-bound immune checkpoints by peripheral blood immune cells
Authors: Reitsema R.D. , Kurt S. , Rangel I. , Hjelmqvist H. , Dreifaldt M. , Sirsjö A. , Kumawat A.K.
Published: August 2024

Cardiovascular events seem to occur more frequently after treatment with immune checkpoint inhibitors. This suggests a possible role of immune checkpoints in accelerating atherosclerosis formation. We therefore aimed to assess the expression of soluble and membrane-bound immune checkpoints in patients with peripheral artery disease (PAD).

We assessed the levels of 14 soluble immune checkpoints in fasting blood plasma of PAD patients (intermittent claudication, n= 37) and healthy controls (HCs, n=39) by Multiplex protein assay. We measured the levels of T-cell immunoglobulin and mucin domain 3 (TIM-3), programmed cell death 1 ligand 1 and 2 (PD-L1/2), B-and T-lymphocyte attenuator (BTLA), programmed cell death 1 (PD-1), glucocorticoid-induced TNRF-related protein (GITR), herpesvirus entry mediator (HVEM), cytotoxic T-lymphocyte associated protein 4 (CTLA-4), indoleamine 2,3-dioxygenase (IDO), CD28, CD27, CD80, CD137 and lymphocyte-activation gene 3 (LAG-3). The surface expression of CD28, PD-L2, PD-1, GITR, LAG-3, TIM-3 and BTLA on peripheral blood immune cells was determined by flow cytometry. Cytokine production capacity was measured by flow cytometry in TIM-3+ T cells to determine immune exhaustion.

Soluble levels of PD-L2 were decreased in PAD patients, but only in females, whereas soluble levels of TIM-3 showed a trend towards increased concentration in female PAD patients. All monocyte subsets had increased frequencies of PD-L2+ cells in PAD patients. CD4+ T cells had increased frequencies of TIM-3+ cells, which showed little overlap with other immune exhaustion markers. TIM-3+ CD4+ T cells appeared to have a low capacity to produce pro-inflammatory cytokines, but a higher capacity to produce IL-10 compared to TIM-3-CD4+ T cells.

We found that PAD patients show differences in expression of both membrane-bound and soluble immune checkpoints. Some of these differences might be caused by prolonged immune activation, although immune exhaustion markers did not always overlap.
Genomically recodedEscherichia coliwith optimized functional phenotypes
Authors: Hemez Colin , Mohler Kyle , Radford Felix , Moen Jack , Rinehart Jesse , Isaacs Farren J.
Published: August 2024

Genomically recoded organisms hold promise for many biotechnological applications, but they may exhibit substantial fitness defects relative to their non-recoded counterparts. We used targeted metabolic screens, genetic analysis, and proteomics to identify the origins of fitness impairment in a model recoded organism,Escherichia coliC321.ΔA. We found that defects in isoleucine biosynthesis and release factor activity, caused by mutations extant in all K-12 lineage strains, elicited profound fitness impairments in C321.ΔA, suggesting that genome recoding exacerbates suboptimal traits present in precursor strains. By correcting these and other C321.ΔA-specific mutations, we engineered C321.ΔA strains with doubling time reductions of 17% and 42% in rich and minimal medium, respectively, compared to ancestral C321. Strains with improved growth kinetics also demonstrated enhanced ribosomal non-standard amino acid incorporation capabilities. Proteomic analysis indicated that C321.ΔA lacks the ability to regulate essential amino acid and nucleotide biosynthesis pathways, and that targeted mutation reversion restored regulatory capabilities. Our work outlines a strategy for the rapid and precise phenotypic optimization of genomically recoded organisms and other engineered microbes.
Otoacoustic emissions but not behavioral measurements predict cochlear-nerve frequency tuning in an avian vocal-communication specialist
Authors: Karosas Diana M. , Gonzales Leslie , Wang Yingxuan , Bergevin Christopher , Carney Laurel H. , Henry Kenneth S.
Published: August 2024

Frequency analysis by the cochlea forms a key foundation for all subsequent auditory processing. Stimulus-frequency otoacoustic emissions (SFOAEs) are a potentially powerful alternative to traditional behavioral experiments for estimating cochlear tuning without invasive testing, as is necessary in humans. Which methods accurately predict cochlear tuning remains controversial due to only a single animal study comparing SFOAE-based, behavioral, and cochlear frequency tuning in the same species. The budgerigar (Melopsittacus undulatus) is a parakeet species with human-like behavioral sensitivity to many sounds and the capacity to mimic speech. Intriguingly, previous studies of critical bands, psychophysical tuning curves, and critical ratios in budgerigars show that behavioral tuning sharpness increases dramatically with increasing frequency from 1-3.5 kHz, doubling once per octave with peak tuning sharpness from 3.5-4 kHz. The pattern contrasts with slower monotonic growth of behavioral tuning sharpness with increasing frequency in other animals, including most avian species, suggesting a possible auditory specialization in budgerigars. We measured SFOAE-based and cochlear-afferent tuning in budgerigars, for comparison to previously reported behavioral results. SFOAE-based and cochlear-afferent tuning sharpness both increased monotonically and relatively slowly for higher frequencies, in contrast to the behavioral pattern. SFOAE-based tuning in budgerigars accurately predicted cochlear frequency tuning, and both measures aligned with typical patterns of cochlear tuning in other species. Divergent behavioral tuning in budgerigars is unlikely attributable to the periphery and could reflect specializations for central processing of masked signals. Our findings highlight the value of SFOAEs for estimating cochlear tuning and caution against direct inference of cochlear tuning from behavioral critical bands, psychophysical tuning curves, and critical ratios.
Amputation Triggers Long-Range Epidermal Permeability Changes in Evolutionarily Distant Regenerative Organisms
Authors: Dooling Kelly E. , Kim Ryan T. , Kim Elane M. , Chen Erica , Abouelela Adnan , Tajer Benjamin J. , Lopez Noah J. , Paoli Julia C. , Powell Connor J. , Luong Anna G. , Wu S.Y. Celeste , Thornton Kara N. , Singer Hani D. , Savage Aaron M. , Bateman Joel , DiTommaso Tia , Payzin-Dogru Duygu , Whited Jessica L.
Published: August 2024

Previous studies have reported that amputation invokes body-wide responses in regenerative organisms, but most have not examined the implications of these changes beyond the region of tissue regrowth. Specifically, long-range epidermal responses to amputation are largely uncharacterized, with research on amputation-induced epidermal responses in regenerative organisms traditionally being restricted to the wound site. Here, we investigate the effect of amputation on long-range epidermal permeability in two evolutionarily distant, regenerative organisms: axolotls and planarians. We find that amputation triggers a long-range increase in epidermal permeability in axolotls, accompanied by a long-range epidermal downregulation in MAPK signaling. Additionally, we provide functional evidence that pharmacologically inhibiting MAPK signaling in regenerating planarians increases long-range epidermal permeability. These findings advance our knowledge of body-wide changes due to amputation in regenerative organisms and warrant further study on whether epidermal permeability dysregulation in the context of amputation may lead to pathology in both regenerative and non-regenerative organisms.

GRAPHICAL ABSTRACT
Improving Type II Diabetes Care in West Africa: A Scoping Review of Barriers, Facilitators and the Way Forward
Authors: Abdul-Samed Abdul-Basit , Jahan Yasmin , Reichenberger Veronika , Peprah Ellen Barnie , Agyekum Mary Pomaa , Lawson Henry , Balabanova Dina , Mirzoev Tolib , Agyepong Irene
Published: August 2024

Background

The prevalence of diabetes is rising rapidly across West Africa, posing a significant public health challenge. Effective diabetes management through accessible and quality primary healthcare is crucial, yet multiple barriers persist. This review aimed to synthesise the available evidence on factors influencing access, utilisation, and quality of diabetes primary care in West Africa.

Methods

Our scoping review followed Arksey and O’Malley’s methodology and PRISMA-ScR guidelines. We comprehensively searched electronic databases and grey literature for studies covering 2000-2023 that reported factors related to diabetes primary care in West African countries. Data was extracted and analysed through a framework synthesis approach integrating the World Health Organisation Operational Framework for Primary Health Care, the Social Determinants of Health model, and the Innovative Care for Chronic Conditions model.

Results

Twelve studies were included from Nigeria (n=7), Ghana (n=4), and Senegal (n=1). Key barriers to access, utilisation, and quality were identified as health system deficiencies, including lack of infrastructure, workforce shortages, supply gaps, fragmented care coordination, absence of standardised guidelines, high costs of care, and limited governance for chronic disease management. Broader determinants of health, such as poverty, gender, cultural beliefs, reliance on traditional medicine, and health policy gaps, were found to influence access to and utilisation of care significantly. Individual-level barriers like psychological distress and delays in care-seeking were also significant. However, family/social support systems emerged as potential facilitators of accessing and utilising PHC services.

Conclusions

Our review indicates a complex interplay between health system deficiencies, deeply rooted cultural beliefs, and lived experiences shaping diabetes care in West Africa. The region’s unique challenges demand a paradigm shift from conventional chronic care models to context-specific, adaptive models. Crucially, the gendered aspects of care and the integration of traditional healing practices emerge as pivotal yet often overlooked factors in diabetes management. Furthermore, addressing the bidirectional relationship between mental health and diabetes offers a promising avenue for improving outcomes. Future strategies must transcend the biomedical model, embracing a sociocultural approach that leverages community assets and addresses structural inequities.
Getting to the bottom of social learning: Chimpanzees copy arbitrary behavior from conspecifics
Authors: van Leeuwen Edwin J. C. , Bryon Emile , Rogers Alex , Balaran Aurore , Motsch Peggy , Brooker Jake S.
Published: August 2024

Studying animal culture has been crucial for understanding the complexities of knowledge transmission and tracing human culture’s evolutionary origins1. Defined as the use of tools to provide clear practical benefits to individuals, well-documented examples of material culture include nut-cracking2and termite fishing3in chimpanzees. Additionally, there is growing interest in animal social traditions, which appear crucial for social interaction and group cohesion. We have previously documented such a tradition, in which chimpanzees copied inserting blades of grass in their ears from one persistent inventor4. Now, over a decade later, we have observed an unrelated group of chimpanzees where 5/8 individuals began wearing grass in their ears and 6/8 from their rectums. As of 2024, one newly introduced chimpanzee has adopted the grass-in-ear behavior. Given that the behaviors were not observed in seven other groups in the same sanctuary (N=148), we conclude that social learning of arbitrary behavior occurred and discuss our findings considering the larger scope of animal culture.
Less, but more: new insights from appendicularians on chordateFgfevolution and the divergence of tunicate lifestyles
Authors: Sánchez-Serna Gaspar , Badia-Ramentol Jordi , Bujosa Paula , Ferrández-Roldán Alfonso , Torres-Águila Nuria P. , Fabregà-Torrus Marc , Wibisana Johannes N. , Mansfield Michael J. , Plessy Charles , Luscombe Nicholas M. , Albalat Ricard , Cañestro Cristian
Published: August 2024

The impact of gene loss on the divergence of taxa and the generation of evolutionary innovations is a fundamental aspect of Evolutionary Biology that remains unclear. Here, using the evolution of the Fibroblast Growth Factors (FGFs) in appendicularians as a case study, we investigate how gene losses have influenced the evolution of chordates, especially the divergence among tunicates. Our work reveals an unprecedented case of massive losses of allFgfgene subfamilies, except for theFgf9/16/20andFgf11/12/13/14, which in turn suffered two bursts of gene duplications. Phylogenetic inferences and genomic analyses of gene synteny conservation, gene architecture, alternative splicing and protein 3D-structure have allowed us to reconstruct the history of appendicularianFgfgenes in the context of chordate evolution, providing compelling evidence supporting the paracrine secreting functions and the intracellular functions of theFgf9/16/20andFgf11/12/13/14subfamilies, respectively. Exhaustive analysis of developmentalFgfexpression inOikopleura dioicaas a model for appendicularians reveals a paradigmatic case of what could be referred as “less, but more”, providing a conceptual evolutionary framework characterized by four associated evolutionary patterns: conservation of ancestralFgfexpression domains; function shuffling between paralogs upon gene loss; innovation of new expression domains after the bursts ofFgfduplications; and the extinction ofFgffunctions linked to gene losses. The findings of this work allow us to formulate novel hypotheses about the potential impact of losses and duplications ofFgfgenes on the transition from an ancestral ascidian-like biphasic lifestyle to a fully free-living style of appendicularians. These hypotheses include the massive co-option ofFgfgenes for the patterning of the oikoblast responsible of the house architecture, and for the development of the tail fin; the recruitment ofFgf11/12/13/14genes into the evolution of a new mouth, and their role modulating neuronal excitability; the evolutionary innovation of an “anterior tail” FGF signaling mesodermal source upon the loss of retinoic acid signaling; and the potential link between the loss ofFgf7/10/22andFgf8/17/18and the loss of drastic metamorphosis, mesenchymal cells and lack of tail absorption in appendicularians, in contrast to ascidians.
Estrus-Tracking Cortical Neurons Integrate Social cues and Reproductive states to Adaptively Control Sexually Dimorphic Sociosexual Behaviors
Authors: Wang Yuping , Song Xinli , Chen Xiangmao , Zhou Ying , Ma Jihao , Zhang Fang , Wei Liqiang , Qi Guoxu , Yadav Nakul , Miao Benjie , Yan Yiming , Yuan Guohua , Mi Da , Rajasethupathy Priyamvada , Ibañez-Tallon Ines , Jia Xiaoxuan , Heintz Nathaniel , Li Kun
Published: August 2024

Female sociosexual behaviors, essential for survival and reproduction, are adaptively modulated by ovarian hormones. However, the neural mechanisms integrating internal hormonal states with external social cues to guide these behaviors remain poorly understood. Here we identified primary estrous-sensitiveCacna1h-expressing medial prefrontal (mPFCCacna1h+) neurons that orchestrate adaptive sociosexual behaviors. Bidirectional manipulation of mPFCCacna1h+neurons drives opposite-sex-directed behavioral shifts between estrus and diestrus females. In males, these neurons serve opposite functions compared to estrus females, mediating sexually dimorphic effects via anterior hypothalamic outputs. Miniscope imaging reveals mixed-representation of self-estrous states and social target sex in distinct mPFCCacna1h+subpopulations, with biased-encoding of opposite-sex social cues in estrus females and males. Mechanistically, ovarian hormone-driven upregulation ofCacna1h-encoded T-type calcium channels underlies estrus-specific activity changes and sexual-dimorphic function of mPFCCacna1h+neurons. These findings uncover a prefrontal circuit that integrates internal hormonal states and target-sex information to exert sexually bivalent top-down control over adaptive social behaviors.
Spin asymmetries for
C
-even quarkonium production as a probe of gluon distributions
Authors: Kato Nanako , Maxia Luca , Pisano Cristian
Published: August 2024

Within the framework of transverse momentum dependent factorization in combination with nonrelativistic quantum chromodynamics (QCD), we study charmonium and bottomonium production in hadronic collisions. We focus on quarkonium states with even charge conjugation, for which the color-singlet production mechanism is expected to be also dominant in the small transverse momentum region, qT2≪4Mc,b2. It is shown that the distributions of linearly polarized gluons inside unpolarized, longitudinally, and transversely polarized protons contribute to the cross sections for scalar and pseudoscalar quarkonia in a very distinctive, parity-dependent way, whereas their effects on higher angular momentum states are strongly suppressed. We derive analytical expressions for single and double spin asymmetries, which would allow for the direct extraction of the gluon transverse momentum dependent distributions, mirroring the phenomenological studies of the Drell-Yan processes aimed at the extraction of their quark counterparts. By adopting Gaussian models for the gluon transverse momentum dependent distributions, which fulfill without saturating everywhere their positivity bounds, we provide numerical predictions for the transverse single-spin asymmetries. These observables could be measured at LHCSpin, the fixed target experiment planned at the LHC.

Published by the American Physical Society
2024
Tricriticality in 4D U(1) lattice gauge theory
Authors: Torres Rafael C. , Cardoso Nuno , Bicudo Pedro , Ribeiro Pedro , McClarty Paul
Published: August 2024

The 4D compact U(1) gauge theory has a well-established phase transition between a confining and a Coulomb phase. In this paper, we revisit this model using state-of-the-art Monte Carlo simulations on anisotropic lattices. We map out the coupling-temperature phase diagram, and determine the location of the tricritical point, T/K0≃0.19, below which the first-order transition is observed. We find the critical exponents of the high-temperature second-order transition to be compatible with those of the 3-dimensional O(2) model. Our results at higher temperatures can be compared with literature results and are consistent with them. Surprisingly, below T/K0≃0.05 we find strong indications of a second tricritical point where the first-order transition becomes continuous. These results suggest an unexpected second-order phase transition extending down to zero temperature, contrary to the prevailing consensus. If confirmed, these findings reopen the question of the detailed characterization of the transition including a suitable field theory description.

Published by the American Physical Society
2024
Cosmology of self-replicating universes in the interior of black holes formed by dark matter-seeded stellar collapse
Authors: Bramante Joseph , Raj Nirmal
Published: August 2024

We show that dark matter with certain minimal properties can convert the majority of baryons in galaxies to black holes over hundred trillion year timescales. We argue that this has implications for cosmologies which propose that new universes are created in black hole interiors. We focus on the paradigm of cosmological natural selection, which connects black hole production to a universe’s likelihood for existing. Further, we propose that the Universe’s timescale for entropy production could be dynamically linked to black hole production in a naturally selected universe. Our Universe would fit this scenario for models of particle dark matter that convert helium white dwarfs to black holes in around a hundred trillion years, where the dominant source of entropy in our Universe is the helium white dwarfs’ stellar progenitors, which cease forming and burning also in around a hundred trillion years. Much of this dark matter could be discovered at ongoing experiments.

Published by the American Physical Society
2024
Celestial Dual for Maximal Helicity Violating Amplitudes
Authors: Melton Walker , Sharma Atul , Strominger Andrew , Wang Tianli
Published: August 2024

It is shown that a 2D conformal field theory consisting of a central charge c Liouville theory, a chiral level one, rank N Kac-Moody algebra, and a weight −3/2 free fermion holographically generate 4D maximal helicity violating tree-level scattering amplitudes. The correlators of this 2D conformal field theory give directly the 4D leaf amplitudes associated to a single hyperbolic slice of flat space. The 4D celestial amplitudes arise in a large-N and semiclassical large-c limit, according to the holographic dictionary, as a translationally invariant combination of leaf amplitudes. A step in the demonstration is showing that the semiclassical limit of Liouville correlators are given by contact 3D anti–de Sitter Witten diagrams.

Published by the American Physical Society
2024
Maximally efficient exchange in thin flow cells using density gradients
Authors: Mitchell Megan E. , Majkrzak Charles F. , Hoogerheide David P.
Published: August 2024

Flow cells are ubiquitous in laboratories and automated instrumentation, and are crucial for ease of sample preparation, analyte addition and buffer exchange. The assumption that the fluids have exchanged completely in a flow cell is often critical to data interpretation. This article describes the buoyancy effects on the exchange of fluids with differing densities or viscosities in thin, circular flow cells. Depending on the flow direction, fluid exchange varies from highly efficient to drastically incomplete, even after a large excess of exchange volume. Numerical solutions to the Navier–Stokes and Cahn–Hilliard equations match well with experimental observations. This leads to quantitative predictions of the conditions where buoyancy forces in thin flow cells are significant. A novel method is introduced for exchanging fluid cells by accounting for and utilizing buoyancy effects that can be essential to obtain accurate results from measurements performed within closed-volume fluid environments.
Powder-diffraction-based structural comparison for crystal structure prediction without prior indexing
Authors: Otero-de-la-Roza Alberto
Published: August 2024

The objective of crystal structure prediction (CSP) is to predict computationally the thermodynamically stable crystal structure of a compound from its stoichiometry or its molecular diagram. Crystal similarity indices measure the degree of similarity between two crystal structures and are essential in CSP because they are used to identify duplicates. Powder-based indices, which are based on comparing X-ray diffraction patterns, allow the use of experimental X-ray powder diffraction data to inform the CSP search. Powder-assisted CSP presents two unique difficulties: (i) the experimental and computational structures are not entirely comparable because the former is subject to thermal expansion from lattice vibrations, and (ii) experimental patterns present features (noise, background contribution, varying peak shapes etc.) that are not easily predictable computationally. This work presents a powder-based similarity index (GPWDF) based on a modification of the index introduced by de Gelder, Wehrens & Hageman [J. Comput. Chem. (2001), 22, 273–289] using cross-correlation functions that can be calculated analytically. Based on GPWDF, a variable-cell similarity index (VC-GPWDF) is also proposed that assigns a high similarity score to structures that differ only by a lattice deformation and which takes advantage of the analytical derivatives of GPWDF with respect to the lattice parameters. VC-GPWDF can be used to identify similarity between two computational structures generated using different methods, between a computational and an experimental structure, and between two experimental structures measured under different conditions (e.g. different temperature and pressure). VC-GPWDF can also be used to compare crystal structures with experimental patterns in combination with an automatic pre-processing step. The proposed similarity indices are simple, efficient and fully automatic. They do not require indexing of the experimental pattern or a guess of the space group, they account for deformations caused by varying experimental conditions, they give meaningful results even when the experimental pattern is of very poor quality, and their computational cost does not increase with the flexibility of the molecular motif.
Three-dimensional alkaline earth metal–organic framework poly[[μ-aqua-aquabis(μ3-carbamoylcyanonitrosomethanido)barium] monohydrate] and its thermal decomposition
Authors: Domasevitch Kostiantyn V. , Senchyk Ganna A. , Ponomarova Vira V. , Lysenko Andrey B. , Krautscheid Harald
Published: August 2024

In the structure of the title salt, {[Ba(μ3-C3H2N3O2)2(μ-H2O)(H2O)]·H2O}
n
, the barium ion and all three oxygen atoms of the water molecules reside on a mirror plane. The hydrogen atoms of the bridging water and the solvate water molecules are arranged across a mirror plane whereas all atoms of the monodentate aqua ligand are situated on this mirror plane. The distorted ninefold coordination of the Ba ions is completed with four nitroso-, two carbonyl- and three aqua-O atoms at the distances of 2.763 (3)–2.961 (4) Å and it is best described as tricapped trigonal prism. The three-dimensional framework structure is formed by face-sharing of the trigonal prisms, via μ-nitroso- and μ-aqua-O atoms, and also by the bridging coordination of the anions via carbonyl-O atoms occupying two out of the three cap positions. The solvate water molecules populate the crystal channels and facilitate a set of four directional hydrogen bonds. The principal Ba–carbamoylcyanonitrosomethanido linkage reveals a rare example of the inherently polar binodal six- and three-coordinated bipartite topology (three-letter notation sit). It suggests that small resonance-stabilized cyanonitroso anions can be utilized as bridging ligands for the supramolecular synthesis of MOF solids. Such an outcome may be anticipated for a broader range of hard Lewis acidic alkaline earth metal ions, which perfectly match the coordination preferences of highly nucleophilic nitroso-O atoms. Thermal analysis reveals two-stage dehydration of the title compound (383 and 473 K) followed by decomposition with release of CO2, HCN and H2O at 558 K.
Responding to employee-based race inequalities in National Health Service (England): accountability and the Workforce Race Equality Standard
Authors: Dhanani Alpa , Chaidali Penny , Sharma Nina , Varoutsa Evangelia
Published: August 2024

Purpose

This paper examines the efforts of National Health Service (England) (NHSE) to respond to employee-based racial inequalities via its Workforce Race Equality Standard (WRES). The WRES constitutes a hybridised accountability initiative with characteristics of the moral and imposed regimes of accountability.

Design/methodology/approach

The study conceptualises the notion of responsive race accountability with recourse to Favotto et al.’s (2022) moral accountability model and critical race theory (CRT), and through it, examines the enactment of WRES at 40 NHSE trusts using qualitative content analysis.

Findings

Despite the progressive nature of the WRES that seeks to nurture corrective actions, results suggest that trusts tend to adopt an instrumental approach to the exercise. Whilst there is some evidence of good practice, the instrumental approach prevails across both the metric reporting that trusts engage in to guide their actions, and the planned actions for progress. These planned actions not only often fail to coalesce with the trust-specific data but also include generic NHSE or equality, diversity and inclusion initiatives and mimetic adoptions of best practice guidance that only superficially address racial concerns.

Social implications

Whilst the WRES is a laudable voluntary achievement, its moral imperative does not appear to have translated into a moral accountability within individual trusts.

Originality/value

Responding to calls for more research at the accounting-race nexus, this study uniquely draws on CRT to conceptualise and examine race accountability.
When virtual others are with me: exploring the influence of social presence in virtual reality wine tourism experiences
Authors: Deng Demi Shenrui , Seo Soobin , Harrington Robert James , Martin David
Published: August 2024

Purpose

The purpose of this study is to examine the role of social presence in enhancing positive behaviors in the virtual reality (VR)-based wine tourism context through an innovative approach.

Design/methodology/approach

Two sequential experimental studies were conducted to test proposed hypotheses using Web and head-mounted display (HMD) VR formats. Specifically, Study 1 probed the influence of social presence on mental imagery, which subsequently impacted destination visit intention, drinking intent and memorable experience. Study 2 used a field experiment to explore the boundary effects of environmental cues (nature versus social) on social presence and a series of behavioral intentions using an HMD format.

Findings

The findings represent one of the first efforts to unravel the influence of social presence on positive behaviors through mental imagery and the moderating role of environmental cues.

Research limitations/implications

This research enhances the understanding of wine tourism, drawing upon social presence theory and stimulus-organism-response framework.

Practical implications

The outcomes provide valuable insights for wine tourism marketers in developing innovative marketing strategies by addressing the usage of social presence and environmental cues in a VR setting.

Originality/value

To the best of the authors’ knowledge, this study is the first to enrich the existing knowledge of wine tourism by exploring the role of social presence and environmental cues in both Web and HMD VR formats.
Sustainability challenges of last-mile logistics and transition to online grocery retailing in sparsely populated areas
Authors: Wu Yong , Wang Bill , Huo Baofeng
Published: August 2024

Purpose

This paper focuses on the last-mile logistics (LML) operations in fulfilling online grocery orders and the related sustainability considerations in sparsely populated areas like Australia. It aims to examine how online groceries in sparsely populated areas can benefit from online business. Specifically, this study seeks to investigate whether a centralized order fulfillment approach is better than the existing approach which fulfills online orders from local grocery stores.

Design/methodology/approach

A multi-method approach is employed to conduct a high level of cost and emission analysis between the existing and the proposed approaches to illustrate the ratios between the two approaches in terms of cost and carbon emissions. Mathematical models are developed with support from the literature. The model is empirically validated with a case study of grocery distribution in the city of Gold Coast, Australia.

Findings

It finds that the centralized order fulfillment approach in sparsely populated areas can achieve LML sustainability with low cost, high efficiency and less double handling. Meanwhile, the separation of in-store and online retailing processes improves the in-store shopping experience and online shopping visibility, jointly improves customer satisfaction, and consequently achieves a positive effect on long-term sustainability. Additionally, the possibility of automating order picking and dispatching at a central place can make the processes more efficient and help build more sustainable grocery retailing supply chains by using more environmentally friendly systems.

Originality/value

This paper offers analytical and empirical insights into the sustainability of multi-channel grocery retailing supply chains. The high-level model developed first incorporates the concept of online shopping adoption rates and can serve as a decision-making tool for practitioners to improve supply chain sustainability in LML.
Exploring the stock market development and sustainable development nexus: insights from emerging market economies
Authors: Bayar Yilmaz , Toader Valentin , Gavriletea Marius Dan , Yelkesen Oguzhan
Published: August 2024

Purpose

Sustainable development is considered a key factor in addressing environmental issues, global inequalities and poverty. This study aims to investigate the impact of stock market indicators on sustainable development across 16 emerging markets from 2003 to 2020.

Design/methodology/approach

The research uses causality and cointegration analyses to explore the relationships between stock market indicators and sustainable development.

Findings

Univariate causality analysis reveals a bidirectional causal relationship between the stock market turnover ratio and sustainable development, as well as a unidirectional relationship from sustainable development to stock market capitalization and total value traded. Panel-level cointegration analysis suggests that only stock market capitalization has a weak positive influence on sustainable development. However, the impact of stock market indicators on sustainable development varies significantly among countries, as revealed by country-level cointegration analysis.

Research limitations/implications

While this study provides valuable insights, it is not without limitations. The findings are limited to the selected emerging markets and the specified timeframe (2003–2020). The complexity of factors influencing sustainable development suggests the need for further exploration in diverse contexts.

Practical implications

Understanding the nuanced relationships between stock market indicators and sustainable development can offer valuable insights for policymakers, investors and stakeholders.

Originality/value

This research contributes to the existing literature by examining the multifaceted connections between stock market indicators and sustainable development, focusing on country-specific causality relationships. The study highlights the reciprocal nature of this relationship, where financial market development can both influence and be influenced by a country's progress toward sustainability. This approach provides a more nuanced understanding of the complex interaction between stock market maturity and sustainability goals.
Unpacking the relationship between export coopetition activities and export sales performance
Authors: Crick James M. , Crick Dave
Published: August 2024

Purpose

While coopetition (cooperation among competitors) has been widely researched in domestic settings, relatively less work has evaluated how small exporters engage in these business-to-business (B2B) marketing strategies. Therefore, export coopetition activities could have different performance outcomes (and boundary conditions) to these B2B marketing practices in domestic arenas. Consequently, underpinned by resource-based theory (and focusing on smaller-sized and internationalised, businesses), the purpose of this paper is to unpack the relationship between export coopetition activities and export sales performance by accounting for key quadratic and moderating effects.

Design/methodology/approach

Survey responses were obtained from 107 small, and export-oriented, wine producers in South Africa. After refining the measurement scales, the quantitative data passed all major assessments of reliability, validity and common method variance. Subsequently, the elements of the conceptual model were tested through a hierarchical regression analysis. Moreover, a post-hoc test was undertaken to delve deeper into the nuances of the statistical results – and offer additional insights concerning how these B2B marketing strategies operate (and manifest) in export markets.

Findings

A significant non-linear (inverted U-shaped) relationship was found between export coopetition activities and export sales performance. No support was found for the moderators, namely, export geographical scope, export intensity or the interaction between these forms of internationalisation. An interesting issue to emerge from the post-hoc test was that export geographical scope yielded a quadratic link with export sales performance, for which the export coopetition activities construct did not moderate this connection (a non-significant interaction effect). These findings offer new insights that help inform the concentration versus spreading debate related to target market strategies.

Originality/value

New evidence emerges on the internationalisation of the coopetition construct, regarding how smaller-sized companies collaborate with their competitors within their export markets. Likewise, stronger insights arise concerning the dark sides of export coopetition activities via circumstances where they are harmful to internationalised firms. Moreover, improved claims are made about how resource-based theory serves as a useful tool to conceptualise the nuances of export coopetition activities and how they impact export sales performance. Collectively, this investigation not only responds to calls for research to evaluate coopetition in export markets but also embraces the complexities of these B2B marketing strategies.
Attitudes toward the adoption of accounting analytics technology in the digital transformation landscape
Authors: Al-Okaily Manaf
Published: August 2024

Purpose

The main purpose of this study is to determine the accounting analytics technology (AAT) adoption among manufacturing small and medium-sized enterprises (SMEs) based on the extended technology acceptance model (TAM).

Design/methodology/approach

The quantitative research approach with online surveys was used to collect data from 219 accounting managers among manufacturing SMEs in Jordan. To test the suggested research model, partial least squares structural equation modeling was used.

Findings

The findings indicated that all direct paths were found to be significant in the hypothesized directions. Ultimately, the results also revealed that perceived usefulness has mediated the relationship between perceived ease of use and intention to use AAT, and hence all direct and indirect hypotheses were accepted.

Originality/value

This research has successfully extended the TAM model in the context of AAT adoption among Jordanian manufacturing SMEs by including new factors along with the original factors of the TAM model, particularly in the postpandemic era.
Negotiating neutrality and activism in Norwegian public libraries: the case of environmental sustainability
Authors: Solum Espen Eigil Barratt-Due
Published: August 2024

Purpose

This article explores how Norwegian public libraries negotiate neutrality and activism in response to national policy implementing the United Nations (UN) goals for sustainable development.

Design/methodology/approach

Informed by the ongoing academic debate on library neutrality and activism, this article presents an analysis of 30 qualitative interviews with librarians and directors in four public libraries. Through comparative case study design, the analysis explores the negotiations of neutrality and activism in the organisational response to the sustainable development goals (SDGs), in public events connected with environmental sustainability and in the engagement of librarians with various higher education backgrounds and competencies.

Findings

The neutrality of Norwegian public libraries is tied to the libraries’ function as a social meeting place and arena for public debate. While the agenda for sustainable development is perceived as neutral by many of the interview participants, there are ongoing negotiations on how politically charged initiatives should be and whether public conversations on environmental and climate issues need to represent a balance of opinions. The case libraries have developed different strategies, and while non-traditional collections and events centred on sustainability may provide a middle ground, the negotiations of neutrality and activism are influenced both by competencies and personal engagement.

Originality/value

This article shows how neutrality is negotiated in public libraries, with the strategies to build a sustainable society through both conventional means and activism.