bluuebunny/crossref_metadata_2025 huggingface dataset:
Silencing of a raspberry homologue ofVRN1is associated with disruption of dormancy induction and misregulation of subsets of dormancy-associated genes
Authors: Mateos Brezo , Preedy Katharine , Milne Linda , Morris Jenny , Hedley Pete E. , Simpson Craig , Hancock Robert D. , Graham Julie
Published: February 2024

Winter dormancy is a key process in the phenology of temperate perennials. The changing climate is severely impacting its course leading to economic losses in agriculture. A better understanding of the underlying mechanisms, as well as the genetic basis of the different responses, are necessary for the development of climate-resilient cultivars. This study aims to provide an insight into winter dormancy in red raspberry (Rubus idaeusL).

We report the transcriptomic profiles during dormancy in two raspberry cultivars with contrasting responses. The cultivar ‘Glen Ample’ showed a typical perennial phenology, whereas ‘Glen Dee’ registered consistent dormancy dysregulation, exhibiting active growth and flowering out of season. RNA-seq combined with weighted gene co-expression network analysis (WGCNA) highlighted gene clusters in both genotypes that exhibited time-dependent expression profiles, Functional analysis of ‘Glen Ample’ gene clusters highlighted the significance of the cell and structural development prior to dormancy entry as well the role of genetic and epigenetic processes such as RNAi and DNA methylation in regulating gene expression. On the contrary, dormancy release in ‘Glen Ample’ was associated with upregulation of transcripts associated with the resumption of metabolism, nucleic acid biogenesis and processing signal response pathways.

Many of the processes occurring in ‘Glen Ample’ were dysregulated in ‘Glen Dee’ and twenty-eight transcripts exhibiting time-dependent expression in ‘Ample’ that also had an Arabidopsis homologue were not found in all samples from ‘Glen Dee’. These included a gene with homology to ArabidopsisVRN1(RiVRN1.1) that exhibited a sharp decline in expression following dormancy induction in Glen Ample. Characterisation of the gene region in the ‘Glen Dee’ genome revealed two large insertions upstream of the ATG start codon. We propose that non-expression of a specific VRN1 homologue in ‘Glen Dee’ causes dormancy misregulation as a result of inappropriate expression of a subset of genes that are directly or indirectly regulated byRiVRN1.1.

HIGHLIGHT

The raspberry cultivar Glen Dee exhibits aberrant winter dormancy status associated with insertions in the upstream promoter region of aVRN1(RiVRN1.1) homologue that silence expression, allowing the identification of dormancy-associated genetic modules that are regulated byRiVRN1.1.
Potent pollen gene regulation by DNA glycosylases in maize
Authors: Zeng Yibing , Somers Julian , Bell Harrison S. , Vejlupkova Zuzana , Dawe R. Kelly , Fowler John E. , Nelms Brad , Gent Jonathan I.
Published: February 2024

Although DNA methylation primarily represses TEs, it also represses select genes that are methylated in plant body tissues but demethylated by DNA glycosylases (DNGs) in endosperm or pollen. Activity of either one of two DNGs, MDR1 or DNG102, is essential for pollen viability in maize. Using single-pollen mRNA sequencing on pollen segregating mutations in both genes, we identified 58 candidate DNG target genes that account for 11.1% of the wild-type transcriptome but are silent or barely detectable in the plant body (sporophyte). They are unusual in their tendency to lack introns but even more so in their having TE-like methylation in their CDS. The majority have predicted functions in cell wall modification, and they likely support the rapid tip growth characteristic of pollen tubes. These results suggest a critical role for DNA methylation and demethylation in regulating maize genes with potential for extremely high expression in pollen but constitutive silencing elsewhere.
COVID-19 vaccination-infection status and immunological profile from India: a case study for prioritizing at risk population for targeted immunization
Authors: Gujjarlapudi Deepika , Mittal Ankit , Gajapathi Raju Vidyavathi Devi , Veturi Sadhana Yelamanchili , Talukdar Rupjyoti , Banerjee Rupa , Jagtap Nitin , Krishnaiah Sannapaneni , Veeraiah Namburu , Duvvur Nageshwar Reddy
Published: February 2024

Background

The COVID-19 pandemic’s global impact was mitigated through rapid vaccine development, leading to a mix of natural and vaccination-derived immunity. Immunological proﬁle in hybrid immunity remains less studies, especially in regions where non-mRNA vaccines were used. This study focuses on the immunological proﬁles and predictors of immune response in one such population.

Methods

This was a cross-sectional study to assess their humoral and cellular immune responses based on vaccination and infection history. Immunological assays were performed to measure antispike protein and neutralizing antibodies as well as interferon-γ release assay. Multivariable linear regression model was used to estimate predictors of immune response.

Results

The study revealed signiﬁcant differences in immune response among participants based on their hybrid immunity status, vaccination, and infection history. Higher antibody titres and cellular responses were observed in individuals with hybrid immunity, especially those with dual pre-Omicron and Omicron infections (3326 BAU/ml, IQR: 770.25-5678.25 and 4.92 IU of IFN-γ/mL, IQR:3.74-16.98 respectively, p <0.001). Age and comorbidities such as diabetes and hypertension were associated with lower antibody levels and cellular response, while vaccination and hybrid immunity correlated with higher immune responses.

Conclusion

The prevalence of hybrid immunity was high, yet a substantial portion of the population lacks it, indicating the necessity for targeted immunization strategies. The ﬁndings underscore the importance of prioritizing high-risk individuals, such as elderly and individuals with comorbidities, for booster vaccinations to enhance community-level protection against COVID-19.
Anti-capsule human monoclonal antibodies protect against hypervirulent and pandrug-resistantKlebsiella pneumoniae
Authors: Roscioli Emanuele , Galli Fonseca Vittoria Zucconi , Bosch Soraya Soledad , Paciello Ida , Maccari Giuseppe , Batani Giampiero , Stazzoni Samuele , Cardinali Giulia , Tiseo Giusy , Giordano Cesira , Shen Yuwei , Capoccia Laura , Ridelfi Matteo , Troisi Marco , Manganaro Noemi , Mugnaini Chiara , Cardamone Dario , Santi Concetta De , Ciabattini Annalisa , Cerofolini Linda , Fragai Marco , Licastro Danilo , Nicolau David P. , Abdelraouf Kamilia , Barnini Simona , Menichetti Francesco , Falcone Marco , Sala Claudia , Kabanova Anna , Rappuoli Rino
Published: February 2024

The silent pandemic caused by antimicrobial resistance (AMR) requires innovative therapeutic approaches. Human monoclonal antibodies (mAbs), which are among the most transformative, safe and effective drugs in oncology and autoimmunity, are rarely used for infectious diseases and not yet used for AMR. Here we applied an antigen-agnostic strategy to isolate extremely potent human mAbs againstKlebsiella pneumoniae(Kp) sequence type 147 (ST147), a hypervirulent and pandrug-resistant clonotype which is spreading globally. Isolated mAbs target the bacterial capsule and the O-antigen. Surprisingly, although both capsule- and O-antigen-specific mAbs displayed bactericidal activity in the picomolar rangein vitro, only the capsule-specific mAbs were protective against fulminant ST147 bloodstream infection. Protection correlated within vitrobacterial uptake by macrophages and enchained bacterial growth. Our study describes the only drug able to protect against pandrug-resistant Kp and provides a strategy to isolate mAbs and identify correlates of protection against AMR bacteria.
Neural Circuit Revision in Retinal Remodeling, A Pathoconnectomics Approach
Authors: Pfeiffer Rebecca L , Dahal Jeebika , Sigulinsky Crystal L , Anderson James R , Barrera Isabel A , Yang Jia-Hui , Haddadin Olivia , Houser Alexis , Garcia Jessica C , Jones Bryan W
Published: February 2024

The Aii glycinergic amacrine cell (Aii) plays a central role in bridging rod pathways with cone pathways, enabling an increased dynamic range of vision from scotopic to photopic ranges. The Aii integrates scotopic signals via chemical synapses from rod bipolar cells (RodBCs) onto the arboreal processes of Aii ACs, injecting signals into ON-cone bipolar cells (CBbs) via gap junctions with Aiis on the arboreal processes and the waist of the Aii ACs. The CBbs then carry this information to ON and OFF ganglion cell classes. In addition, the Aii is involved in the surround inhibition of OFF cone bipolar cells (CBas) through glycinergic chemical synapses from Aii ACs onto CBas. We have previously shown changes in RodBC connectivity as a consequence of rod photoreceptor degeneration in a pathoconnectome of early retinal degeneration: RPC1. Here, we evaluated the impact of rod photoreceptor degeneration on the connectivity of the Aii to determine the impacts of photoreceptor degeneration on the downstream network of the neural retina and its suitability for integrating therapeutic interventions as rod photoreceptors are lost. Previously, we reported that in early retinal degeneration, prior to photoreceptor cell loss, Rod BCs make pathological gap junctions with Aiis. Here, we further characterize this altered connectivity and additional shifts in both the excitatory drive and gap junctional coupling of Aiis in retinal degeneration, along with discussion of the broader impact of altered connectivity networks. New findings reported here demonstrate that Aiis make additional gap junctions with CBas increasing the number of BC classes that make pathological gap junctional connectivity with Aiis in degenerating retina. In this study, we also report that the Aii, a tertiary retinal neuron alters their synaptic contacts early in photoreceptor degeneration, indicating that rewiring occurs in more distant members of the retinal network earlier in degeneration than was previously predicted. This rewiring impacts retinal processing, presumably acuity, and ultimately its ability to support therapeutics designed to restore image-forming vision. Finally, these Aii alterations may be the cellular network level finding that explains one of the first clinical complaints from human patients with retinal degenerative disease, an inability to adapt back and forth from photopic to scotopic conditions.
Exact centriole counts are critical for B cell development but not function
Authors: Schapfl Marina A. , LoMastro Gina M. , Braun Vincent Z. , Hirai Maretoshi , Levine Michelle S. , Kiermaier Eva , Labi Verena , Holland Andrew J. , Villunger Andreas
Published: February 2024

Centrioles define centrosome structure and function. Deregulation of centriole numbers can cause developmental defects and foster malignant disease. The p53 tumor suppressor limits the growth of cells lacking or harboring additional centrioles and can be engaged by the “mitotic surveillance” or the “PIDDosome pathway”, respectively. Here, we show that early B cell progenitors frequently present extra centrioles that are rapidly lost during maturation. Increasing centriole counts beyond physiological levels by Polo-like kinase 4 (PLK4) overexpression induces apoptosis, suggesting clearance of such cells during development. Remarkably, this apoptotic response is independent of PIDD1 or p53, but can be blocked by excess BCL2. In contrast, loss of centrosomes uponPlk4deletion arrests B cell development at the pro B cell stage. This defect can be rescued by co-deletion ofUsp28, a critical component of the mitotic surveillance pathway that restores cell number and function in the absence of centrioles. In both scenarios, too many and too few centrosomes, mitochondrial apoptosis is engaged to kill B cells with abnormal centriole counts during their development with progenitor B cells being intolerant to centriole loss but permissive to centriole amplification. Unexpectedly, our findings show that centrioles are dispensable for mounting an effective humoral immune response.
Presynaptic Nrxn3 is essential for ribbon-synapse assembly in hair cells
Authors: Jukic Alma , Lei Zhengchang , Cebul Elizabeth R. , Pinter Katherine , Mosqueda Natalie , David Sandeep , Tarchini Basile , Kindt Katie
Published: February 2024

Hair cells of the inner ear rely on specialized ribbon synapses to transmit sensory information to the central nervous system. The molecules required to assemble these synapses are not fully understood. We show that Nrxn3, a presynaptic adhesion molecule, is critical for ribbon-synapse assembly in hair cells. In both mouse and zebrafish models, loss of Nrxn3 results in significantly fewer intact ribbon synapses. In zebrafish we demonstrate that a 60% loss of synapses innrxn3mutants dramatically reduces both presynaptic responses in hair cells and postsynaptic responses in afferent neurons. Despite a reduction in synapse function in this model, we find no deficits in the acoustic startle response, a behavior reliant on these synapses. Overall, this work demonstrates that Nrxn3 is a critical and conserved molecule required to assemble ribbon synapses. Understanding how ribbon synapses assemble is a key step towards generating novel therapies to treat forms of age-related and noise-induced hearing loss that occur due to loss of ribbon synapses.

Summary Statement

Hearing and balance depend on specialized ribbon synapses that transmit sensory stimuli between hair cells and afferent neurons. We identify Nrxn3 as a key molecular player in ribbon-synapse assembly in hair cells.
High-throughput investigation of genetic design constraints in domesticated Influenza A Virus for transient gene delivery
Authors: Sychla Adam , Stach Christopher S , Roach Shanley N , Hayward Amanda N , Langlois Ryan A , Smanski Michael J
Published: February 2024

Replication-incompetent single cycle infectious Influenza A Virus (sciIAV) has demonstrated utility as a research and vaccination platform. Protein-based therapeutics are increasingly attractive due to their high selectivity and potent efficacy but still suffer from low bioavailability and high manufacturing cost. Transient RNA-mediated delivery is a safe alternative that allows for expression of protein-based therapeutics within the target cells or tissues but is limited by delivery efficiency. Here, we develop recombinant sciIAV as a platform for transient gene deliveryin vivoandin vitrofor therapeutic, research, and manufacturing applications (in vivoantimicrobial production, cell culture contamination clearance, and production of antiviral proteinsin vitro). While adapting the system to deliver new protein cargo we discovered expression differences presumably resulting from genetic context effects. We applied a high-throughput screen to map these within the 3′-untranslated and coding regions of the hemagglutinin-encoding segment 4. This screen revealed permissible mutations in the 3′-UTR and depletion of RNA level motifs in the N-terminal coding region.
Paired metagenomic and chemical evaluation of an aflatoxin contaminated dog kibble
Authors: Ottesen Andrea , Kocurek Brandon , Reed Elizabeth , Commichaux Seth , Mammel Mark , Ramachandran Padmini , McDermott Patrick , Flannery Brenna M. , Strain Errol
Published: February 2024

Identification of chemical toxins from complex or highly processed foods can present ‘needle in the haystack’ challenges for chemists. Metagenomic data can guide chemical toxicity evaluations with DNA-based description of the wholistic composition (bacterial, eukaryotic, protozoal, viral, and antimicrobial resistance) of any food suspected to harbor toxins, allergens, or pathogens. This approach can focus chemistry-based diagnostics, improve risk assessment, and address data gaps. There is increasing recognition that simultaneously co-occurring mycotoxins, either from single or multiple species, can impact dietary toxicity. Here we evaluate an aflatoxin contaminated kibble with known levels of specific mycotoxins and demonstrate that the abundance of DNA from putative aflatoxigenicAspergillusspp. correlated with levels of aflatoxin quantified by Liquid Chromatography Mass Spectrometry (LCMS). Metagenomic data also identified an expansive range of co-occurring fungal taxa which may produce additional mycotoxins. Metagenomic data paired with chemical data provides a novel modality to address current data gaps pertaining to mycotoxin toxicity exposures, toxigenic fungal taxonomy, and mycotoxins of emerging concern.
Maramycin, a cytotoxic isoquinolinequinone terpenoid produced through heterologous expression of a bifunctional indole prenyltransferase /tryptophan indole-lyase inS. albidoflavus
Authors: Maleckis Matiss , Wibowo Mario , Williams Sam E. , Gotfredsen Charlotte H. , Sigrist Renata , Souza Luciano D.O. , Cowled Michael S. , Charusanti Pep , Gren Tetiana , Saha Subhasish , Moreira José M. A. , Weber Tilmann , Ding Ling
Published: February 2024

Isoquinolinequinones represent an important family of natural alkaloids with profound biological activities. Heterologous expression of a rare bifunctional indole prenyltransferase /tryptophan indole-lyase enzyme fromStreptomyces mirabilisP8-A2 inS. albidoflavusJ1074 led to the activation of a putative isoquinolinequinone biosynthetic gene cluster and production of a novel isoquinolinequinone alkaloid, named maramycin (1). The structure of maramycin was determined by analysis of spectroscopic (1D/2D NMR) and MS spectrometric data. The prevalence of this bifunctional biosynthetic enzyme was explored and found to be a recent evolutionary event with only a few representatives in Nature. Maramycin exhibited moderate cytotoxicity against human prostate cancer cell lines, LNCaP and C4-2B. The discovery of maramycin (1) enriched the chemical diversity of natural isoquinolinequinones and also provided new insights into crosstalk between the host biosynthetic genes and the heterologous biosynthetic genes in generating new chemical scaffolds.
Virus-free CRISPR knock-in of a chimeric antigen receptor intoKLRC1generates potent GD2-specific natural killer cells
Authors: Shankar Keerthana , Zingler-Hoslet Isabella , Shi Lei , Katta Varun , Russell Brittany E. , Tsai Shengdar Q. , Capitini Christian M. , Saha Krishanu
Published: February 2024

Natural killer (NK) cells are an appealing off-the-shelf, allogeneic cellular therapy due to their cytotoxic profile. However, their activity against solid tumors remains suboptimal in part due to the upregulation of NK-inhibitory ligands, such as HLA-E, within the tumor microenvironment. Here, we utilize CRISPR-Cas9 to disrupt theKLRC1gene (encoding the HLA-E-binding NKG2A receptor) and perform non-viral insertion of a GD2-targeting chimeric antigen receptor (CAR) within NK cells isolated from human peripheral blood. Genome editing with CRISPR/Cas9 ribonucleoprotein complexes yields efficient genomic disruption of theKLRC1gene with 98% knockout efficiency and specific knock-in of the GD2 CAR transgene as high as 23%, with minimal off-target activity as shown by CHANGE-Seq, in-out PCR, and next generation sequencing.KLRC1-GD2 CAR NK cells display high viability and proliferation, as well as precise cellular targeting and potency against GD2+human melanoma cells. Notably,KLRC1-GD2 CAR NK cells overcome HLA-E-based inhibition by HLA-E-expressing, GD2+melanoma cells. Using a single-step, virus-free genome editing workflow, this study demonstrates the feasibility of precisely disrupting inhibitory signaling within NK cells via CRISPR/Cas9 while expressing a CAR to generate potent allogeneic cell therapies against HLA-E+solid tumors.
Addressing Artemisinin Resistance in Malaria Treatment: A Novel Ferrous ACT (FACT) Formulation
Authors: Wang Yuliang , Tang Kexuan
Published: February 2024

Malaria is the worldwide infectious disease causing significant losses of human lives every year. The deployment of artemisinin-based combination therapies (ACTs) has helped to reduce the losses caused by malaria. However, resistance to ACTs evolved especially by Plasmodium falciparum occurs and becomes more and more threats for human lives. Up to now, there is no effective way to solve this drug-resistance problem. Here we propose a new ACT, which contains traditional ACT plus iron supplement, so-called ferrous ACT (FACT). The FACT is promising to become a safe and effective new formulation to combat ACT resistance malaria, helping WHO reach its 2030's Malaria Control Goal.
Motif Interactions Affect Post-Hoc Interpretability of Genomic Convolutional Neural Networks
Authors: Lemanczyk Marta S. , Bartoszewicz Jakub M. , Renard Bernhard Y.
Published: February 2024

Post-hoc interpretability methods are commonly used to understand decisions of genomic deep learning models and reveal new biological insights. However, interactions between sequence regions (e.g. regulatory elements) impact the learning process as well as interpretability methods that are sensitive to dependencies between features. Since deep learning models learn correlations between the data and output that do not necessarily represent a causal relationship, it is difficult to say how well interacting motif sets are fully captured. Here, we investigate how genomic motif interactions influence model learning and interpretability methods by formalizing possible scenarios where interaction effects appear. This includes the choice of negative data and non-additive effects on the outcome. We generate synthetic data containing interactions for those scenarios and evaluate how they affect the performance of motif detection. We show that post-hoc interpretability methods can miss motifs if interactions are present depending on how negative data is defined. Furthermore, we observe differences in interpretability between additive and non-additive effects as well as between post-hoc interpretability methods.
Long-range chemical signallingin vivois regulated by mechanical signals
Authors: Pillai Eva K. , Mukherjee Sudipta , Gampl Niklas , McGinn Ross J. , Mooslehner Katrin A. , Becker Julia M. , Winkel Alex , Thompson Amelia J. , Franze Kristian
Published: February 2024

Biological processes are regulated by chemical and mechanical signals, yet the interaction between these signalling modalities remains poorly understood. Using the developingXenopus laevisbrain as a model system, we identified a critical crosstalk between tissue stiffness and long-range chemical signallingin vivo. Targeted knockdown of the mechanosensitive ion channel Piezo1 in retinal ganglion cells (RGCs) led to pathfinding errorsin vivo.However, pathfinding errors were also observed in RGCs expressing Piezo1, when Piezo1 was downregulated in the surrounding brain tissue. Depleting Piezo1 in the brain parenchyma led to a decrease in the expression of the long-range chemical guidance cues Semaphorin3A (Sema3A) and Slit1, which instruct turning responses in distant cells. Furthermore, Piezo1 knockdown markedly reduced tissue stiffness. This tissue softening was independent of Sema3A depletion, and was caused by a decrease in the cell-cell adhesion proteins NCAM1 and N-Cadherin. Downregulating NCAM1 and N-Cadherin was sufficient to reduce tissue stiffness and Sema3A expression. Conversely, increasing environmental stiffnessex vivoresulted in enhanced tissue-level force generation and an increase in Slit1 and Sema3A expression. Moreover, stiffening soft brain regionsin vivoinduced ectopic Sema3A production via a Piezo1-dependent mechanism. Hence, tissue mechanics can locally modulate the availability of diffusive, long-range chemical signals, thus influencing cell function at sites distant from the mechanical cue. Such indirect regulatory mechanisms of cell function through mechanical signals are likely widespread across biological systems.
A ratiometric ER calcium sensor for quantitative comparisons across cell types and subcellular regions
Authors: Farrell Ryan J. , Bredvik Kirsten G. , Hoppa Michael B. , Hennigan S. Thomas , Brown Timothy A. , Ryan Timothy A.
Published: February 2024

The endoplasmic reticulum (ER) is an important regulator of Ca2+in cells and dysregulation of ER calcium homeostasis can lead to numerous pathologies. Understanding how various pharmacological and genetic perturbations of ER Ca2+homeostasis impacts cellular physiology would likely be facilitated by more quantitative measurements of ER Ca2+levels that allow easier comparisons across conditions. Here, we developed a ratiometric version of our original ER-GCaMP probe that allows for more quantitative comparisons of the concentration of Ca2+in the ER across cell types and sub-cellular compartments. Using this approach we show that the resting concentration of ER Ca2+ in primary dissociated neurons is substantially lower than that in measured in embryonic fibroblasts.
Multifunctional polymerization domains determine the onset of epigenetic silencing in Arabidopsis
Authors: Schulten Anna , Jang Geng-Jen , Payne-Dwyer Alex , Fiedler Marc , Nielsen Mathias L , Bienz Mariann , Leake Mark C , Dean Caroline
Published: February 2024

Cold-induced epigenetic silencing of Arabidopsis FLOWERING LOCUS C (FLC) requires the Polycomb Repressive Complex 2 and accessory proteins VIN3 and VRN5. VIN3 and VRN5 interact via head-to-tail VEL polymerization domains, but how these functionally contribute to the switch to an epigenetically silenced state remains poorly understood. Here, we determine that VIN3 VEL polymerization involves higher order nuclear VIN3 assemblies in vivo, promotes strong chromatin association and efficient H3K27me3 nucleation. However, we also show that the polymerization domains of VIN3 and VRN5 are not equivalent: VRN5 VEL domain is not required for silencing despite its role in physically connecting VIN3 with the PRC2 complex and VRN5 VEL is unable to functionally replace VIN3 VEL in vivo. Both VIN3 and VRN5 homologs are present throughout angiosperm species, suggesting a functional requirement for maintaining different polymerization modalities. This work reveals distinct roles for multifunctional polymerization domains of Polycomb accessory proteins underpinning the onset of epigenetic silencing.
Microwave power harvesting using resonator-coupled double quantum dot photodiode
Authors: Haldar Subhomoy , Zenelaj Drilon , Potts Patrick P. , Havir Harald , Lehmann Sebastian , Dick Kimberly A. , Samuelsson Peter , Maisi Ville F.
Published: February 2024

We demonstrate a microwave power-to-electrical energy conversion in a resonator-coupled double quantum dot. The system, operated as a photodiode, converts individual microwave photons to electrons tunneling through the double dot, resulting in an electrical current flowing against the applied voltage bias at input powers down to 1 fW. The device attains a maximum power harvesting efficiency of 2%, with the photon-to-electron conversion efficiency reaching 12% in the single-photon absorption regime. We find that the power conversion depends on thermal effects showing that thermodynamics plays a crucial role in the single-photon energy conversion.

Published by the American Physical Society
2024
Bounds on quartic gauge couplings in HEFT from electroweak gauge boson pair production at the LHC
Authors: Éboli O. J. P. , Gonzalez-Garcia M. C. , Martines Matheus
Published: February 2024

Precision measurements of anomalous quartic couplings of electroweak gauge bosons allow us to search for deviations of the Standard Model predictions and signals of new physics. Here, we obtain the constraints on anomalous quartic gauge couplings using the presently available data on the production of gauge-boson pairs via vector boson fusion. We work in the Higgs effective theory framework and obtain the present bounds on the operator’s Wilson coefficients. We show that the combination of different datasets breaks the degeneracies in analysis with more than one nonvanishing Wilson coefficient. Anomalous quartic gauge boson couplings lead to rapidly growing cross sections and we discuss the impact of a unitarization procedure on the attainable limits.

Published by the American Physical Society
2024
Finite system size correction to the effective coupling in
ϕ4
scattering
Authors: Horowitz W. A. , Plessis J. F. Du
Published: February 2024

We compute and explore numerically the finite system size correction to next-to-leading-order 2→2 scattering in massive scalar ϕ4 theory. The derivation uses “denominator regularization” (instead of the usual dimensional regularization) on a spacetime with spatial directions compactified to a torus, with characteristic lengths not necessarily of equal size. We determine a useful analytic continuation of the generalized Epstein zeta function to isolate the usual UV divergence. Self-consistently, the renormalized finite system size correction reduces to zero as the system size goes to infinity and, further, satisfies the optical theorem. One of our checks of unitarity leads to a generalization of a number-theoretic result from Hardy and Ramanujan. Precise numerical exploration of the finite system size correction to the amplitude and coupling when two spatial dimensions are finite requires the exploitation of the analytic structure of the finite system size result via a dispersion relation. We find that the finite system size scattering amplitude exhibits “geometric” bound states. Even away from these bound states, the finite system size correction to the effective coupling can be large.

Published by the American Physical Society
2024
Nonlocal Electrodynamics in Ultrapure
PdCoO2
Authors: Baker Graham , Branch Timothy W. , Bobowski J. S. , Day James , Valentinis Davide , Oudah Mohamed , McGuinness Philippa , Khim Seunghyun , Surówka Piotr , Maeno Yoshiteru , Scaffidi Thomas , Moessner Roderich , Schmalian Jörg , Mackenzie Andrew P. , Bonn D. A.
Published: February 2024

The motion of electrons in the vast majority of conductors is diffusive, obeying Ohm’s law. However, the recent discovery and growth of high-purity materials with extremely long electronic mean free paths has sparked interest in non-Ohmic alternatives, including viscous and ballistic flow. Although non-Ohmic transport regimes have been discovered across a range of materials—including two-dimensional electron gases, graphene, topological semimetals, and the delafossite metals—determining their nature has proved to be challenging. Here, we report on a new approach to the problem, employing broadband microwave spectroscopy of the delafossite metal PdCoO2 in three distinct sample geometries that would be identical for diffusive transport. The observed differences, which go as far as differing power laws, take advantage of the hexagonal symmetry of the conducting Pd planes of PdCoO2. This permits a particularly elegant symmetry-based diagnostic for nonlocal electrodynamics, with the result favoring predominantly ballistic over strictly hydrodynamic flow. Furthermore, it uncovers a new effect for ballistic electron flow, owing to the highly faceted shape of the hexagonal Fermi surface. We combine our extensive data set with an analysis of the Boltzmann equation to characterize the nonlocal regime in PdCoO2, and we include out-of-plane impurity scattering as a source of apparent momentum-conserving scattering at low temperatures. More broadly, our results highlight the potential of broadband microwave spectroscopy to play a central role in investigating exotic transport regimes in the new generation of ultrahigh-conductivity materials.

Published by the American Physical Society
2024
Isostructural behaviour in ammonium and potassium salt forms of sulfonated azo dyes
Authors: Kennedy Alan R. , Kirkhouse Jennifer B. A. , McCarney Karen M. , Puissegur Olivier
Published: February 2024

The structures of five ammonium salt forms of monosulfonated azo dyes, derivatives of 4-(2-phenyldiazen-1-yl)benzenesulfonate, with the general formula [NH4][O3S(C6H4)NN(C6H3)RR′]·XH2O [R = OH, NH2 or N(C2H4OH)2; R′ = H or OH] are presented. All form simple layered structures with alternating hydrophobic (organic) and hydrophilic (cation, solvent and polar groups) layers. To assess for isostructural behaviour of the ammonium cation with M
+ ions, the packing of these structures is compared with literature examples. To aid this comparison, the corresponding structures of four potassium salt forms of the monosulfonated azo dyes are also presented herein. Of the five ammonium salts it is found that three have isostructural equivalents. In two cases this equivalent is a potassium salt form and in one case it is a rubidium salt form. The isostructurality of ion packing and of unit-cell symmetry and dimensions tolerates cases where the ammonium ions form somewhat different interaction types with coformer species than do the potassium or rubidium ions. No sodium salt forms are found to be isostructural with any ammonium equivalent. However, similarities in the anion packing within a single hydrophobic layer are found for a group that consists of the ammonium and rubidium salt forms of one azo anion species and the sodium and silver salt forms of a different azo species.
Mapping the intellectual structure and knowledge base of food literacy research: a bibliometric analysis
Authors: McManus Sarah , Pendergast Donna , Kanasa Harry
Published: February 2024

Purpose

Food literacy is a multidimensional concept that prioritises the aspects individuals require to navigate the contemporary foodscape successfully. The study aims to map the knowledge base and intellectual structure of the concept of food literacy to assess if the most cited definitions reflect these constructs.

Design/methodology/approach

The inclusion criteria of full-text, peer-reviewed articles or conference papers, in English, using “food literacy” within the title, abstract, keywords or linked to the research focus produced 538 articles from the Scopus database from its inception until January 31, 2023. Articles were analysed according to exponential growth, geolocations, authors, articles, research areas and keywords using VOSviewer, CiteSpace and Excel.

Findings

Food literacy research grew exponentially between 2012 and 2022 at a rate of 50% and spanned 62 research areas, with nutrition and dietetics being the most common. Vidgen and Gallegos were the most cited authors of the most cited article, and Australia was the most influential food literacy research geolocation. Research originating from developing countries within Asia, the Middle East, Africa and South America was underrepresented, and COVID-19 impacted research trends between 2020 and 2023.

Practical implications

It is recommended to link “food literacy” to appropriate publications to increase its visibility and that food literacy be redefined and conceptualised to better reflect its intellectual structure. To complete this task, further research guided by keyword clustering can enhance conceptual understanding.

Originality/value

This study provides new insight into the knowledge base and intellectual structure of food literacy and provides scope for future research to develop the concept further.
To integrate or not? Understanding knowledge integration of target firm
Authors: Varshney Mayank
Published: February 2024

Purpose

Technology acquisition is a common phenomenon of acquiring external knowledge, but we have a limited understanding of conditions in which the acquirer integrates the target or not. On one hand, the acquirer may have a policy to integrate the target to benefit from its prior knowledge. On the other hand, the target may face challenges in continuing its knowledge creation and the acquirer may want to provide it autonomy to not disrupt it. This paper aims to identify conditions in which targets tend to be less integrated after acquisitions, allowing them to maintain more autonomy and contribute more to knowledge creation.

Design/methodology/approach

We test our arguments in the empirical setting of the global biopharmaceutical industry using a difference-in-difference approach on a longitudinal dataset of matched patents. We examine self-cites received by patents belonging to acquirers and the targets before and after the acquisitions.

Findings

We find that, on average, the targets’ prior patents do not receive more self-cites after the acquisition. We conclude that this is because their R&D activities are disrupted, suggesting a higher level of post-acquisition integration. However, more nuanced findings reveal that it may not be the case all the time. When the target has more research experience, is international or is specialized in complementary technologies, prior patents of targets continue to receive more self-cites after the acquisition. It indicates that the targets in such conditions continue knowledge creation, suggesting a lower level of post-acquisition integration.

Originality/value

Our findings contribute to post-acquisition integration research. While post-acquisition integration downside is common, we present conditions in which such a downside may be less likely. We highlight that the context of an acquisition may be an important determinant of the extent of integration of the target. Moreover, we supplement the integration research (cultural, structural and human resource and leadership perspectives of integration) by adding a knowledge-based perspective to it. Such dynamics have important implications for acquirers and targets in deriving value from the acquisition.
We need bigger mirrors: the importance of fat fiction for young readers
Authors: Foos Kristen A.
Published: February 2024

Purpose

This paper aims to investigate how narrative is constructed to create connections with fat readers, how books function to envision spaces of fat liberation for young readers and to highlight the incredible importance of providing bigger mirrors (Bishop, 1990) for fat representation in children’s literature.

Design/methodology/approach

This paper analyzes and reflects on two texts that contain counternarratives of fatness: The (Other) F Word: A celebration of the fat and fierce edited by Angie Manfredi (2019) and Big by Vashti Harrison (2023) to interrogate how these two narratives intentionally disrupt anti-fat bias.

Findings

Body size and fatness are identities that need to be included in diversity efforts within education. Books like The (Other) F Word: A celebration of the fat and fierce (Manfredi, 2019) and Big (Harrison, 2023) offer positive representations of fatness, disrupt biases around body size and provide spaces that allow fat students to find joy, hope, connection and, more than anything, imagine a way toward liberation.

Research limitations/implications

This paper highlights the need to include more narratives of positive fat representation within children’s literature and calls for educators to interrogate their own anti-fat biases and practices.

Originality/value

There is a lack of research on fat representation specifically within children and young adult literature. This paper provides an analysis of two pieces of literature with fat representation that brings attention to the need for this type of future research.
Gender and entrepreneurial intention in low-income countries: the relative roles played by anticipated financial returns versus perceived barriers for university students in Sierra Leone
Authors: Bradley Wendy A. , Fry Caroline
Published: February 2024

Purpose

The purpose of the present study is to investigate the extent to which female and male university students from low-income countries express different entrepreneurial intentions. Specifically, the study empirically tests whether the anticipated financial returns to entrepreneurship versus salaried employment, or the perceived barriers to entrepreneurship exert a stronger influence on the relationship between gender and entrepreneurial intentions.

Design/methodology/approach

To test the relationship of anticipated rewards versus barriers to entrepreneurship on gender and entrepreneurial intention, the study uses new data from a field survey in Sierra Leone and employs multiple mediation analyses.

Findings

The authors find that the relationship between gender and entrepreneurial intentions operates through the mediator of perceptions of the financial returns to entrepreneurship but not perceived barriers to entrepreneurship.

Research limitations/implications

The authors study intent, not behavior, acknowledging that cognitive intent is a powerful predictor of later behavior. Implications for future research on entrepreneurship in the African context are discussed.

Practical implications

The results from this study can be applied to both pedagogic and business settings in the field of entrepreneurship, with concrete implications for policymakers.

Originality/value

Results suggest that the gender gap in entrepreneurial intentions (EI) for science, technology, engineering and mathematics (STEM)- and business-educated students in Sierra Leone is predominantly influenced by anticipated financial returns to occupational choices, as opposed to perceived barriers to entrepreneurship, a more frequently studied antecedent to EI.
Mapping the landscape: a bibliometric analysis of ISO 31000
Authors: Widianti Tri , Firdaus Himma , Rakhmawati Tri
Published: February 2024

Purpose

This study aims to evaluate performance and map the science of research on International Organization for Standardization (ISO) 31000 standard through published articles. Specifically, this study determines the current state of the art, identifies research gaps and guides future studies related to ISO 31000.

Design/methodology/approach

This work investigates and examines the research papers acquired from the Scopus and Web of Science databases. Inclusion and exclusion criteria were applied to obtain relevant papers. Bibliometric analysis using Biblioshiny was conducted to answer the research objectives.

Findings

The results show growing interest in ISO 31000 research but limited interconnectivity among articles. Influential journals have emerged, highlighting key research trends in risk management's (RM) practical application and its significance in organizational decision-making. Key research areas include risk assessment (RA) methods, enterprise RM and system integration, endorsing ISO 31000 as a valuable tool. Future research should prioritize longitudinal studies to track ISO 31000's impact, study effective risk communication strategies, explore sector-specific RM practices and assess ISO 31000's application in emerging technologies.

Research limitations/implications

This research reveals key themes and diverse methods that aid practitioners in customizing industry risk strategies, adapting to emerging trends, engaging global collaboration and improving risk communication. Nevertheless, the study might overlook non-English contributions, urging broader language inclusion for ISO 31000's profundity.

Originality/value

This paper's originality lies in its comprehensive bibliometric analysis of ISO 31000 research, providing valuable insights into the standard's growing significance and global impact. The study identifies key research themes and influential authors, guiding future research and improving RM practices.
Do selected board governance mechanisms strengthen the link between institutional and macroeconomic variables and the financial flexibility of corporations? Empirical evidence from an emerging economy
Authors: Wijerathna Harshani Shashikala , Anuradha Niluka , Ajward Roshan
Published: February 2024

Purpose

This study aims to explore the relationship between institutional and macroeconomic factors and corporate financial flexibility while also investigating the moderating impact of selected board governance mechanisms on this relationship.

Design/methodology/approach

The sample of the study comprises 174 firms listed on the Colombo Stock Exchange for a period of eight years, from 2014 to 2021. Data were collected from secondary sources, and both descriptive and inferential statistical techniques were used for analyses.

Findings

Corporate financial flexibility is notably affected by profitability as an institutional factor and by gross domestic product growth rate and banking sector development as macroeconomic factors. Furthermore, the relationship between a company’s profitability and corporate financial flexibility is found to be moderated by selected board governance mechanisms. However, these governance mechanisms do not influence the relationship between corporate financial flexibility and other institutional factors (i.e. other than profitability) and macroeconomic factors considered in this study.

Originality/value

This study adds a fresh perspective to the existing body of knowledge in the field of corporate finance by emphasizing the interaction effect of board governance mechanisms on the association between macroeconomic and institutional variables and financial flexibility of firms. The findings are expected to be useful for business decision-makers in managing their corporate financial flexibility effectively and maximizing the use of their financial resources.
Adoption of distributed ledger technology for construction projects: a study of the challenges in a developing country
Authors: Oke Ayodeji Emmanuel , Aliu John , Ehiosun Lydia Uyi , Kineber Ahmed Farouk , Stephen Seyi Segun
Published: February 2024

Purpose

The construction industry in Nigeria, like many others worldwide, grapples with increasing demands for enhanced efficiency, transparency and security. While distributed ledger technology (DLT) offers substantial potential in tackling these issues, its implementation faces numerous obstacles. This study aims to investigate the challenges hindering the adoption of DLT within the Nigerian construction sector, capitalizing on a recognized research gap in this field.

Design/methodology/approach

A comprehensive literature review identified 20 challenges to DLT adoption. A structured questionnaire was developed and distributed to 98 construction professionals selected from a pool of 5,330 members using purposive and snowball sampling. Background information was assessed using frequency and percentage, data normality with the Shapiro–Wilk test and nonparametric data compared using the Kruskal–Wallis H-test. Factor analysis was then used to reduce the challenges into a more coherent set.

Findings

Findings revealed the top five challenges: power supply issues, data privacy and compliance, an uncertain legal framework, insufficient training and education and a lack of skilled workforce. Further analysis revealed four clusters of challenges, namely, technical and infrastructure barriers, organizational and cultural challenges, financial and economic challenges and regulatory and legal challenges.

Practical implications

Through the evaluation of challenges and potential strategies to overcome them, this study aims to lay a foundation that assists construction entities in effectively harnessing the benefits of DLT while navigating the obstacles inherent in its adoption.

Originality/value

This study contributes to the existing body of knowledge by offering insights into the challenges surrounding the adoption of DLT, specifically within the Nigerian construction sector. By juxtaposing the findings from this study with existing research conducted in other countries such as India, South Africa and the USA, a more comprehensive understanding of the challenges unique to the Nigerian context can be gained.