bluuebunny/crossref_metadata_2025 huggingface dataset:
Kinesin-II motors differentially impact biogenesis of distinct extracellular vesicle subpopulations shed fromC. eleganssensory cilia
Authors: Clupper Michael , Gill Rachael , Elsayyid Malek , Touroutine Denis , Caplan Jeffrey L. , Tanis Jessica E.
Published: December 2021

Extracellular vesicles (EVs) are bioactive lipid-bilayer enclosed particles released from nearly all cells. One specialized site for EV shedding is the primary cilium, a conserved signaling organelle. The mechanisms underlying cargo enrichment and biogenesis of heterogeneous EVs shed from cilia are unclear. Here we discover the conserved ion channel CLHM-1 as a new ciliary EV cargo. Using super-resolution microscopy, we imaged EVs released into the environment from sensory neuron cilia ofC. elegansexpressing fluorescently-tagged CLHM-1 and TRP polycystin-2 channel PKD-2 EV cargoes at endogenous levels. We find that these proteins are enriched in distinct EV subpopulations that are differentially shed in response to availability of hermaphrodite mating partners. Both CLHM-1 and PKD-2 localize to the ciliary base and middle segment of the cilium proper, but PKD-2 alone is present in the cilium distal tip and EVs shed from this site. CLHM-1 EVs released into the environment bud from a secondary site, the periciliary membrane compartment at the ciliary base. We show that individual heterotrimeric and homomeric kinesin-II motors have discrete impacts on the colocalization of PKD-2 and CLHM-1 in both cilia and EVs. Total loss of kinesin-II activity significantly decreases shedding of PKD-2 but not CLHM-1 EVs. Our data demonstrate that anterograde kinesin-II-dependent intraflagellar transport is required for selective enrichment of specific protein cargoes into heterogeneous EVs with different signaling potentials.
mRNA-1273 and BNT162b2 mRNA vaccines have reduced neutralizing activity against the SARS-CoV-2 Omicron variant
Authors: Edara Venkata-Viswanadh , Manning Kelly E. , Ellis Madison , Lai Lilin , Moore Kathryn M. , Foster Stephanie L. , Floyd Katharine , Davis-Gardner Meredith E. , Mantus Grace , Nyhoff Lindsay E. , Bechnak Sarah , Alaaeddine Ghina , Naji Amal , Samaha Hady , Lee Matthew , Bristow Laurel , Hussaini Laila , Ciric Caroline Rose , Nguyen Phuong-Vi , Gagne Matthew , Roberts-Torres Jesmine , Henry Amy R. , Godbole Sucheta , Grakoui Arash , Sexton Marybeth , Piantadosi Anne , Waggoner Jesse J. , Douek Daniel C. , Anderson Evan J. , Rouphael Nadine , Wrammert Jens , Suthar Mehul S.
Published: December 2021

The BNT162b2 (Pfizer-BioNTech) and mRNA-1273 (Moderna) vaccines generate potent neutralizing antibodies against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). However, the global emergence of SARS-CoV-2 variants with mutations in the spike protein, the principal antigenic target of these vaccines, has raised concerns over the neutralizing activity of vaccine-induced antibody responses. The Omicron variant, which emerged in November 2021, consists of over 30 mutations within the spike protein. Here, we used an authentic live virus neutralization assay to examine the neutralizing activity of the SARS-CoV-2 Omicron variant against mRNA vaccine-induced antibody responses. Following the 2nd dose, we observed a 30-fold reduction in neutralizing activity against the omicron variant. Through six months after the 2nd dose, none of the sera from naïve vaccinated subjects showed neutralizing activity against the Omicron variant. In contrast, recovered vaccinated individuals showed a 22-fold reduction with more than half of the subjects retaining neutralizing antibody responses. Following a booster shot (3rd dose), we observed a 14-fold reduction in neutralizing activity against the omicron variant and over 90% of boosted subjects showed neutralizing activity against the omicron variant. These findings show that a 3rd dose is required to provide robust neutralizing antibody responses against the Omicron variant.
Efficacy of antiviral drugs against the omicron variant of SARS-CoV-2
Authors: Dabrowska Agnieszka , Szczepanski Artur , Botwina Paweł , Mazur-Panasiuk Natalia , Jiřincová Helena , Rabalski Lukasz , Zajic Tomas , Popowicz Grzegorz , Pyrc Krzysztof
Published: December 2021

The Omicron variant of the SARS-CoV-2 virus was first detected in South Africa in November 2021. The analysis of the sequence data in the context of earlier variants suggested that it may show very different characteristics, including immune evasion and increased transmission. These assumptions were partially confirmed, and the reduction in protection in convalescent patients and vaccinated individuals have been confirmed. Here, we have evaluated the efficacy of antivirals against SARS-CoV-2 variants, Omicron, Delta, and the early 2020 isolate.
THEMIS is a priming substrate of non-receptor tyrosine phosphatase PTPN6/SHP1 and plays dual roles during T cell development
Authors: Zhang Jiali , Zuo Erwei , Song Minfang , Chen Li , Jiang Zhenzhou , Chen Shengmiao , Xiong Xuexue , Wang Yuetong , Hao Piliang , Horng Tiffany , Zhuang Min , Zhang Liye , Wang Haopeng , Fan Gaofeng
Published: December 2021

THEMIS plays an indispensable role in T cells, but its mechanism of action is highly controversial. Using the systematic proximity labeling methodology PEPSI, we identified THEMIS as an uncharacterized substrate for the phosphatase SHP1. Saturated mutagenesis analysis revealed that THEMIS phosphorylation at the evolutionally conserved Tyr34 residue was oppositely regulated by SHP1 and the kinase LCK. Like THEMIS-/-mice, THEMISY34F/Y34Fknock-in mice showed a significant decrease in CD4 thymocytes and mature CD4 T cells, but a normal thymic development and peripheral homeostasis of CD8 T cells. Mechanistically, phosphorylated THEMIS induced by TCR activation acts as a “priming substrate” to bind SHP1 and convert its phosphatase activity from basal level to nearly fully activated level, ensuring an appropriate negative regulation of TCR signaling. However, cytokine signaling in CD8 T cells failed to elicit THEMIS Y34 phosphorylation, revealing both phosphorylation-dependent and -independent roles of THEMIS in controlling T cell maturation and expansion.
The C-terminal tail of polycystin-1 suppresses cystic disease in a mitochondrial enzyme-dependent fashion
Authors: Onuchic Laura , Padovano Valeria , Schena Giorgia , Rajendran Vanathy , Dong Ke , Gresko Nikolay P. , Shi Xiaojian , Shen Hongying , Somlo Stefan , Caplan Michael J.
Published: December 2021

Autosomal dominant polycystic kidney disease (ADPKD) is the most prevalent potentially lethal monogenic disorder. Approximately 78% of cases are caused by mutations in the PKD1 gene, which encodes polycystin-1 (PC1). PC1 is a large 462-kDa protein that undergoes cleavage in its N and C-terminal domains. C-terminal cleavage produces fragments that translocate to mitochondria. We show that transgenic expression of a protein corresponding to the final 200 amino acid residues of PC1 in a Pkd1-KO orthologous murine model of ADPKD dramatically suppresses cystic phenotype and preserves renal function. This suppression depends upon an interaction between the C-terminal tail of PC1 and the mitochondrial enzyme Nicotinamide Nucleotide Transhydrogenase. This interaction modulates tubular/cyst cell proliferation, the metabolic profile, mitochondrial function and the redox state. Together, these results suggest that a short fragment of PC1 is sufficient to suppress cystic phenotype and open the door to the exploration of gene therapy strategies for ADPKD.
Liquid-liquid phase separation facilitates the biogenesis of secretory storage granules
Authors: Parchure Anup , Tian Meng , Boyer Cierra K , Bearrows Shelby C , Rohli Kristen E , Zhang Jianchao , Ramazanov Bulat R , Wang Yanzhuang , Stephens Samuel B , von Blume Julia
Published: December 2021

Insulin is a key regulator of human metabolism, and its dysfunction leads to diseases such as type 2 diabetes. It remains unknown how proinsulin is targeted from the trans-Golgi network (TGN) to secretory storage granules as no cargo receptor has been identified. Chromogranin proteins (CGs) are central regulators of granule biosynthesis, and it was proposed that their aggregation is critical for this process. However, the molecular mechanism by which these molecules facilitate sorting at the TGN is poorly understood. Here, we show that CGs undergo liquid–liquid phase separation (LLPS) at low pH independently of divalent cations, such as calcium. Liquid CG condensates, but not aggregates, recruit and sort proinsulin and other granule-destined cargo molecules towards secretory granules. Cargo selectivity is independent of sequence or structural elements but is based on the size and concentration of the client molecules at the TGN. Finally, electrostatic interactions and the N-terminal intrinsically disordered domain of chromogranin B facilitate LLPS and are critical for granule formation. We propose that phase-separated CGs act as a “cargo sponge” within the TGN lumen, gathering soluble client proteins into the condensate independently of specific sequence or structural elements, facilitating receptor-independent sorting. These findings challenge the canonical TGN sorting models and provide insights into granule biosynthesis in insulin-secreting β-cells.

One sentence summary

Liquid Chromogranin condensates recruit cargo molecules at the TGN for their delivery to secretory storage granules.
Live-cell microscopy or fluorescence anisotropy with budded baculoviruses - which way to go with measuring ligand binding to M4 muscarinic receptors?
Authors: Tahk Maris-Johanna , Torp Jane , Ali Mohammed A.S. , Fishman Dmytro , Parts Leopold , Grätz Lukas , Müller Christoph , Keller Max , Veiksina Santa , Laasfeld Tõnis , Rinken Ago
Published: December 2021

M4 muscarinic receptor is a G protein-coupled receptor that has been associated with alcohol and cocaine abuse, Alzheimer’s disease and schizophrenia which makes it an interesting drug target. For many G protein-coupled receptors, the development of high-affinity fluorescence ligands has expanded the options for high throughput screening of drug candidates and serve as useful tools in fundamental receptor research. So far, the lack of suitable fluorescence ligands has limited studying M4 receptor ligand binding. Here, we explored the possibilities of using fluorescence-based methods for studying binding affinity and kinetics to M4 receptor of both labeled and unlabeled ligands. We used two TAMRA-labeled fluorescence ligands, UR-MK342 and UR-CG072, for assay development. Using budded baculovirus particles as M4 receptor preparation and fluorescence anisotropy method, we determined the affinities and binding kinetics of both fluorescence ligands. The fluorescence ligands could also be used as reported probes for determining binding affinities of a set of unlabeled ligands. Based on these results, we took a step further towards a more natural signaling system and developed a method using live CHO-K1-hM4R cells and automated fluorescence microscopy suitable for routine determination of unlabeled ligand affinities. For quantitative image analysis, we developed random forest and deep learning-based pipelines for cell segmentation. The pipelines were integrated into the user-friendly open-source Aparecium software. Both developed methods were suitable for measuring fluorescence ligand saturation binding, association and dissociation kinetics as well as for screening binding affinities of unlabeled ligands.

Abstract Figure
Preserving protein homeostasis prevents motor impairment in DNA Damage Response-compromised C. elegans
Authors: Huiting Wouter , Duque-Jaramillo Alejandra , Seinstra Renée I. , Kampinga Harm. H. , Nollen Ellen A.A. , Bergink Steven
Published: December 2021

To maintain genome integrity, cells rely on a complex system of DNA repair pathways and cell cycle checkpoints, together referred to as the DNA damage response (DDR). Impairments in DDR pathways are linked to cancer, but also to a wide range of degenerative processes, frequently including progressive neuropathy and accelerated aging. How defects in mechanistically distinct DDR pathways can drive similar degenerative phenotypes is not understood. Here we show that defects in various DDR components are linked to a loss of protein homeostasis in Caenorhabditis elegans. Prolonged silencing of atm-1, brc-1 or ung-1, central components in respectively checkpoint signaling, double strand break repair and base excision repair enhances the global aggregation of proteins occurring in adult animals, and accelerates polyglutamine protein aggregation in a model for neurodegenerative diseases. Overexpression of the molecular chaperone HSP-16.2 prevents enhanced protein aggregation in atm-1, brc-1 or ung-1-compromised animals. Strikingly, rebalancing protein homeostasis with HSP-16.2 almost completely rescues age-associated impaired motor function in these animals as well. This reveals that the consequences of a loss of atm-1, brc-1 or ung-1 converge on an impaired protein homeostasis to cause degeneration. These findings indicate that a loss of protein homeostasis is a crucial downstream consequence of DNA repair defects, and thereby provide an attractive novel framework for understanding the broad link between DDR defects and degenerative processes.
A novel zebrafish model of SPEG-related centronuclear myopathy (CNM): characterization and comparison with other CNM model zebrafish
Authors: Espinosa Karla G. , Geissah Salma , Groom Linda , Volaptti Jonathan , Scott Ian C. , Dirksen Robert T. , Zhao Mo , Dowling James J.
Published: December 2021

Centronuclear myopathy (CNM) is a congenital neuromuscular disorder caused by pathogenic variation in genes associated with membrane trafficking and excitation-contraction coupling (ECC). Bi-allelic autosomal recessive mutations in striated muscle enriched protein kinase (SPEG) account for a subset of CNM patients. Previous research has been limited by the perinatal lethality of Speg knockout mice. Thus, the precise biological role of SPEG in skeletal muscle remains unknown. To address this issue, we generated zebrafish spega, spegb, and spega/spegb (speg-DKO) mutant lines. We demonstrate that speg-DKO zebrafish faithfully recapitulate multiple phenotypes associated with human CNM, including disruption of the ECC protein machinery, dysregulation of calcium homeostasis during ECC, and impairment of muscle performance. Taking advantage of the availability of zebrafish models of multiple CNM genetic subtypes, we compared novel and known disease markers in speg-DKO with mtm1-KO and DNM2-S619L transgenic zebrafish. We observed desmin (DES) accumulation common to all CNM subtypes, and DNM2 upregulation in muscle of both speg-DKO and mtm1-KO zebrafish. In all, we establish a new model of SPEG-related CNM, and identify abnormalities in this model suitable for defining disease pathomechanisms and evaluating potential therapies.

Summary Statement

We created a novel zebrafish speg mutant model of centronuclear myopathy that recapitulates key features of the human disorder and provides insight into pathomechanisms of the disease.
Sexual and individual signatures are encoded in the temporal rate of Cape gannet display calls
Authors: Bowmaker-Falconer Kezia , Thiebault Andrea , Connan Maёlle , Aubin Thierry , Charrier Isabelle , Pistorius Pierre
Published: December 2021

1.

Abstract/Summary

Vocalisations play a vital role in animal communication, as they are involved in many biological functions. Seabirds often breed in large and dense colonies, making successful recognition between mates or between parents -and offspring crucial for reproductive success. Most seabird species, including Cape gannets (Morus capensis), are monomorphic and likely rely on acoustic signals for mate selection and mate recognition. This study aimed to better understand the use of vocalisations for sex and individual recognition in Cape gannets by describing the acoustic structure of their display calls at the nest. Vocalisations of nesting Cape gannets were recorded and acoustic measurements were extracted in both temporal and frequency domains. Values of the fundamental frequency and the average of Inter-Onset-Interval appeared to be the most important acoustic variables for sex determination. Both temporal and frequency parameters showed a potential for individual identity coding, with the average units’ Inter-Onset-Interval being the most important variable for individual identification for both sexes. This study provides the first evidence of sex-specific and individual vocal signatures in adult breeding Cape gannets. From an applied perspective, identified sex specific differences could potentially be used as a non-invasive method for field-based sex-determination in research and monitoring projects on Cape gannets.
New cell biological explanations for kinesin-linked axon degeneration
Authors: Liew Yu-Ting , Voelzmann André , Pinho-Correia Liliana M. , Murphy Thomas , Tortoishell Haydn , Parkin Jill , Bailey David M.D. , Landgraf Matthias , Prokop Andreas
Published: December 2021

Axons are the slender, up to meter-long projections of neurons that form the biological cables wiring our bodies. Most of these delicate structures must survive for an organism’s lifetime, meaning up to a century in humans. Axon maintenance requires life-sustaining motor protein-driven transport distributing materials and organelles from the distant cell body. It seems logic that impairing this transport causes systemic deprivation linking to axon degeneration. But the key steps underlying these pathological processes are little understood. To investigate mechanisms triggered by motor protein aberrations, we studied more than 40 loss- and gain-of-function conditions of motor proteins, cargo linkers or further genes involved in related processes of cellular physiology. We used one standardisedDrosophilaprimary neuron system and focussed on the organisation of axonal microtubule bundles as an easy to assess readout reflecting axon integrity. We found that bundle disintegration into curled microtubules is caused by the losses of Dynein heavy chain and the Kif1 and Kif5 homologues Unc-104 and Kinesin heavy chain (Khc). Using point mutations of Khc and functional loss of its linker proteins, we studied which of Khc’s sub-functions might link to microtubule curling. One cause was emergence of harmful reactive oxygen species through loss of Milton/Miro-mediated mitochondrial transport. In contrast, loss of the Kinesin light chain linker caused microtubule curling through an entirely different mechanism appearing to involve increased mechanical challenge to microtubule bundles through de-inhibition of Khc. The wider implications of our findings for the understanding of axon maintenance and pathology are discussed.
Functional design of bacterial superoxide:quinone oxidoreductase
Authors: Abou-Hamdan Abbas , Mahler Roman , Grossenbacher Philipp , Biner Olivier , Sjöstrand Dan , Lochner Martin , Högbom Martin , von Ballmoos Christoph
Published: December 2021

The superoxide anion - molecular oxygen reduced by a single electron - is produced in large amounts by enzymatic and adventitious reactions and can perform a range of cellular functions, including bacterial warfare and iron uptake, signalling and host immune response in eukaryotes. However, it also serves as precursor for more deleterious species such as the hydroxyl anion or peroxynitrite and therefore, cellular defense mechanisms for superoxide neutralization have evolved. In addition to the soluble proteins superoxide dismutase and superoxide reductase, recently the membrane embedded diheme cytochrome b561(CybB) from E. coli has been proposed to act as a superoxide:quinone oxidoreductase. Here, we confirm superoxide and cellular ubiquinones or menaquinones as natural substrates and show that quinone binding to the enzyme accelerates the reaction with superoxide. The reactivity of the substrates is in accordance with the here determined midpoint potential of the two b hemes (+48 and -23 mV / NHE). Our data suggest that the enzyme can work near the diffusion limit in the forward direction and can also catalyse the reverse reaction efficiently under physiological conditions. The data is discussed in context of described cytochrome b561 proteins and potential physiological roles of CybB.
Mechanism of stepwise electron transfer in six-transmembrane epithelial antigen of the prostate (STEAP) 1 and 2
Authors: Chen Kehan , Wang Lie , Shen Jiemin , Tsai Ah-lim , Zhou Ming , Wu Gang
Published: December 2021

Six transmembrane epithelial antigen of the prostate (STEAP) is a family of membrane-embedded hemoproteins with four members, STEAP1-4, all of which have a transmembrane domain (TMD) that chelates a heme prosthetic group. STEAP2-4, but not STEAP1, have an intracellular oxidoreductase domain (OxRD) so that an electron transfer chain composed of NADPH, FAD, and heme is established to mediate electron transfer across cell membranes. However, it is not known whether STEAP1 can establish a physiologically relevant electron transfer chain. Here we show that reduced FAD binds to STEAP1 and enables reduction of the heme. We also show that a soluble cytochromeb5reductase can dock on STEAP1 and serve as a surrogate OxRD to reduce the heme. These results provide the first evidence that STEAP1 can support a cross-membrane electron transfer chain. It is not clear whether FAD, which relays electrons from NADPH to heme and interacts with both OxRD and TMD, remains constantly bound to the STEAPs. We found that FAD reduced by STEAP2 can be utilized by STEAP1, supporting the hypothesis that FAD is diffusible rather than staying bound to STEAP2. We determined the structure of human STEAP2 in complex with NADP+and FAD to an overall resolution of 3.2 Å by cryo-electron microscopy. The structure of STEAP2 shows that the two cofactors bind similarly to those in the STEAP4 structure and thus a diffusible FAD is likely a general feature of the electron transfer mechanism in the STEAPs. The structure of STEAP2 also shows that its extracellular regions are less structured than those of STEAP4 or STEAP1, and further experiments show that STEAP2 reduces Fe3+-NTA with a rate significantly slower than STEAP1. These results establish a solid foundation for understanding the function and mechanisms of STEAP family of proteins.
Limited allele-specific gene expression in highly polyploid sugarcane
Authors: Margarido Gabriel Rodrigues Alves , Correr Fernando Henrique , Furtado Agnelo , Botha Frederik C. , Henry Robert James
Published: December 2021

Polyploidy is widespread in plants, allowing the different copies of genes to be expressed differently in a tissue-specific or developmentally specific way. This allele-specific expression (ASE) has been widely reported, but the proportion and nature of genes showing this characteristic have not been well defined. We now report an analysis of the frequency and patterns of ASE at the whole-genome level in the highly polyploid sugarcane genome. Very high depth whole-genome sequencing and RNA sequencing revealed strong correlations between allelic proportions in the genome and in expressed sequences. This level of sequencing allowed discrimination of each of the possible allele doses in this 12-ploid genome. Most genes were expressed in direct proportion to the frequency of the allele in the genome with examples of polymorphisms being found with every possible discrete level of dose from 1:11 for single-copy alleles to 12:0 for monomorphic sites. The rarer cases of ASE were more frequent in the expression of defense-response genes, as well as in some processes related to the biosynthesis of cell walls. ASE was more common in genes with variants that resulted in significant disruption of function. The low level of ASE may reflect the recent origin of polyploid hybrid sugarcane. Much of the ASE present can be attributed to strong selection for resistance to diseases in both nature and domestication.
The Euler characteristic as a basis for teaching topology concepts to crystallographers
Authors: Naskręcki Bartosz , Jaskolski Mariusz , Dauter Zbigniew
Published: December 2021

The simple Euler polyhedral formula, expressed as an alternating count of the bounding faces, edges and vertices of any polyhedron, V − E + F = 2, is a fundamental concept in several branches of mathematics. Obviously, it is important in geometry, but it is also well known in topology, where a similar telescoping sum is known as the Euler characteristic χ of any finite space. The value of χ can also be computed for the unit polyhedra (such as the unit cell, the asymmetric unit or Dirichlet domain) which build, in a symmetric fashion, the infinite crystal lattices in all space groups. In this application χ has a modified form (χm) and value because the addends have to be weighted according to their symmetry. Although derived in geometry (in fact in crystallography), χm has an elegant topological interpretation through the concept of orbifolds. Alternatively, χm can be illustrated using the theorems of Harriot and Descartes, which predate the discovery made by Euler. Those historical theorems, which focus on angular defects of polyhedra, are beautifully expressed in the formula of de Gua de Malves. In a still more general interpretation, the theorem of Gauss–Bonnet links the Euler characteristic with the general curvature of any closed space. This article presents an overview of these interesting aspects of mathematics with Euler's formula as the leitmotif. Finally, a game is designed, allowing readers to absorb the concept of the Euler characteristic in an entertaining way.
Real-time X-ray imaging of mouse cerebral microvessels in vivo using a pixel temporal averaging method
Authors: Yu Fucheng , Wang Feixiang , Li Ke , Du Guohao , Deng Biao , Xie Honglan , Yang Guoyuan , Xiao Tiqiao
Published: December 2021

Rodents are used extensively as animal models for the preclinical investigation of microvascular-related diseases. However, motion artifacts in currently available imaging methods preclude real-time observation of microvessels in vivo. In this paper, a pixel temporal averaging (PTA) method that enables real-time imaging of microvessels in the mouse brain in vivo is described. Experiments using live mice demonstrated that PTA efficiently eliminated motion artifacts and random noise, resulting in significant improvements in contrast-to-noise ratio. The time needed for image reconstruction using PTA with a normal computer was 250 ms, highlighting the capability of the PTA method for real-time angiography. In addition, experiments with less than one-quarter of photon flux in conventional angiography verified that motion artifacts and random noise were suppressed and microvessels were successfully identified using PTA, whereas conventional temporal subtraction and averaging methods were ineffective. Experiments performed with an X-ray tube verified that the PTA method could also be successfully applied to microvessel imaging of the mouse brain using a laboratory X-ray source. In conclusion, the proposed PTA method may facilitate the real-time investigation of cerebral microvascular-related diseases using small animal models.
Crystal structure and molecular docking study of diethyl 2,2′-({[(1E,1′E)-(hydrazine-1,2-diylidene)bis(methanylylidene)]bis(4,1-phenylene)}bis(oxy))diacetate
Authors: Daoui Said , Kansiz Sevgi , Aktas Feyzi Alkim , Dege Necmi , Saif Eiad , Benchat Noureddine , Karrouchi Khalid
Published: December 2021

The title Schiff base, C22H24N2O6, adopts anEconfiguration. The molecule is planar, the mean planes of the phenyl ring system (r.m.s deviation = 0.0059 Å) forms a dihedral angle of 0.96 (4)° with the mean plane of the phenyl ring moiety (r.m.s deviation = 0.0076 Å). In the crystal, molecules are linked by weak intermolecular C—H...O and C—H...N hydrogen bonds into chains extending along thec-axis andb-axis directions, respectively. A molecular docking study between the title molecule and 5-HT2C, which is a G protein receptor and ligand-gated ion channels found in nervous systems (PDB ID: 6BQH) was executed. The experiment shows that it is a good potential agent because of its affinity and ability to stick to the active sites of the receptor.
Does a retailer's performance depend on CSR practices? A stakeholder theory perspective from developing economy
Authors: Kumar Anil , Singh Rohit Kr
Published: December 2021

Purpose

The study aims to examine the relationship between retailer's performance and corporate social responsibility (CSR) practices in Indian context. The article introduces a new conceptual model considering the parameters as per the stakeholder theory perspective.

Design/methodology/approach

The authors conducted empirical research with CSR practices (CSRP) and other parameters to evaluate the retailers' performance using stakeholder theory. The authors present the results from 292 valid responses from the Indian retailers. The study used structured equation modeling (SEM) to present the analysis and the results.

Findings

Findings indicate that CSRP along with additional constructs loyalty (L), reputation (R), customer satisfaction (CS) and competitive advantage (CA) have positive and significant impact on organizational performance (OP).

Practical implications

The framework will serve as a guiding tool to the management of the retail outlets to examine carefully the link among CSRP with other variables presented in the study and subsequently to the retail outlet performance. The retailers must be more focused on the expectations and demands of the customers concerning products and services for better growth of the firms.

Originality/value

The uniqueness of the study lies in “CSR practices enabled integrated model” to examine the performance of the organizations. The proposed theoretical model would add value to the existing literature to help the retailers in process of their performance improvement.
A design science approach to developing and evaluating items for the assessment of transversal professional competences
Authors: Fahrenbach Florian
Published: December 2021

Purpose

Relying on a design science paradigm, the purpose of this paper is to describe the development and evaluation of items for an ICT artefact that supports the assessment of transversal professional competences within the validation of prior learning (VPL). To do so, the authors build a conceptual bridge between the Occupational Information Network (O*NET) and the European Qualifications Framework (EQF).

Design/methodology/approach

Design science research paradigm, in particular the participatory development of candidate items and their evaluation in a multi-stakeholder approach.

Findings

The authors find that a self-assessment of professional competences should be comprised of 160 items in order to cover the breadth and depth of the O*NET in the hierarchical taxonomy. Such quantity of items sufficiently builds a conceptual bridge between the O*NET and the; EQF.

Practical implications

When designing procedures for the VPL, it is imperative to bear in mind the purpose of the validation procedure, in order to determine relevant stakeholders and their needs in advance as well as the; required language proficiency of the assessment instrument.

Social implications

The innovative value of this approach lies in the combination of an underlying hierarchical taxonomy with assessment items that are developed based on the qualification standards of different Austrian professions. Together with specific verbs that were adapted for each particular item, an innovative self-assessment is proposed. Thereby the authors aim to account for some of the mentioned shortcomings of the EQF.

Originality/value

This paper applies a design science paradigm to develop an ICT artefact that should support the VPL. By reflecting on the design process, the authors introduce a theoretical bridge between the O*NET and the EQF. Thereby the authors aim to account for some of the mentioned shortcomings of the EQF.
Evaluating the sustainable use of mobile payment contactless technologies within and beyond the COVID-19 pandemic using a hybrid SEM-ANN approach
Authors: Al-Sharafi Mohammed A. , Al-Qaysi Noor , Iahad Noorminshah A. , Al-Emran Mostafa
Published: December 2021

Purpose

While there is an abundant amount of literature studies on mobile payment adoption, there is a scarce of knowledge concerning the sustainable use of mobile payment contactless technologies. As those technologies are mainly concerned with security and users' trust, the question of how security factors and trust can influence the sustainable use of those technologies within and beyond the COVID-19 pandemic is still unanswered. This research thus develops a theoretical model based on integrating the protection motivation theory (PMT) and the expectation-confirmation model (ECM), extended with perceived trust (PT) to explore the sustainable use of mobile payment contactless technologies.

Design/methodology/approach

The developed model is evaluated based on data collected through a web-based survey from 523 users who used contactless payment technologies. Unlike the existing literature, the collected data were analyzed using a hybrid structural equation modeling-artificial neural network (SEM-ANN) technique.

Findings

The data analysis results reinforced all the proposed relationships in the developed model. The sensitivity analysis results showed that PT has the largest impact on the sustainable use of mobile payment contactless technologies with 97.2% normalized importance, followed by self-efficacy (SE) (77%), satisfaction (72.1%), perceived vulnerability (PV) (48.9%), perceived usefulness (PU) (48.2%), perceived severity (PS) (40.7%), response efficacy (RE) (28.7%) and response costs (RCs) (24.1%).

Originality/value

The originality of this research lies behind the development of an integrated model based on PMT and ECM to understand the sustainable use of mobile payment contactless technologies. The study provides several managerial implications for decision-makers, policy-makers and service providers to ensure the sustainability of those contactless technologies within and beyond the COVID-19 pandemic.
Artificial intelligent chatbots as brand promoters: a two-stage structural equation modeling-artificial neural network approach
Authors: Lee Crystal T. , Pan Ling-Yen , Hsieh Sara H.
Published: December 2021

Purpose

This study investigates the determinants of effective human and artificial intelligence (AI) relationship-building strategies for brands. It explores the antecedents and consequences of consumers' interactant satisfaction with communication and identifies ways to enhance consumer purchase intention via AI chatbot promotion.

Design/methodology/approach

Microsoft Xiaoice served as the focal AI chatbot, and 331 valid samples were obtained. A two-stage structural equation modeling-artificial neural network approach was adopted to verify the proposed theoretical model.

Findings

Regarding the IQ (intelligence quotient) and EQ (emotional quotient) of AI chatbots, the multi-dimensional social support model helps explain consumers' interactant satisfaction with communication, which facilitates affective attachment and purchase intention. The results also show that chatbots should emphasize emotional and esteem social support more than informational support.

Practical implications

Brands should focus more on AI chatbots' emotional and empathetic responses than functional aspects when designing dialogue content for human–AI interactions. Well-designed AI chatbots can help marketers develop effective brand promotion strategies.

Originality/value

This research enriches the human–AI interaction literature by adopting a multi-dimensional social support theoretical lens that can enhance the interactant satisfaction with communication, affective attachment and purchase intention of AI chatbot users.
Artificial intelligence in agricultural value chain: review and future directions
Authors: Ganeshkumar C. , Jena Sanjay Kumar , Sivakumar A. , Nambirajan T.
Published: December 2021

Purpose

This paper is a literature review on use of artificial intelligence (AI) among agricultural value chain (AVC) actors, and it brings out gaps in research in this area and provides directions for future research.

Design/methodology/approach

The authors systematically collected literature from several databases covering 25 years (1994–2020). They classified literature based on AVC actors present in different stages of AVC. The literature was analysed using Nvivo 12 (qualitative software) for descriptive and content analysis.

Findings

Fifty percent of the reviewed studies were empirical, and 35% were conceptual. The review showed that AI adoption in AVC could increase agriculture income, enhance competitiveness and reduce cost. Among the AVC stages, AI research related to agricultural processing and consumer sector was very low compared to input, production and quality testing. Most AVC actors widely used deep learning algorithm of artificial neural networks in various aspects such as water resource management, yield prediction, price/demand forecasting, energy efficiency, optimalization of fertilizer/pesticide usage, crop planning, personalized advisement and predicting consumer behaviour.

Research limitations/implications

The authors have considered only AI in the AVC, AI use in any other sector and not related to value chain actors were not included in the study.

Originality/value

Earlier studies focussed on AI use in specific areas and actors in the AVC such as inputs, farming, processing, distribution and so on. There were no studies focussed on the entire AVC and the use of AI. This review has filled that literature gap.
ISM-MICMAC approach for analysis of project-based learning barriers
Authors: Kundu Goutam Kumar , Perwez Syed Khalid
Published: December 2021

Purpose

This paper aims to identify and model the key barriers to implementation of project-based learning (PjBL) in higher educational institution.

Design/methodology/approach

Using the interpretive structural modelling (ISM) technique, the study has developed a hierarchical-based model, depicting the mutual relationships amongst the key barriers to implementation of PjBL. Additionally, the paper has performed Matrice d’ Impacts Croises Multiplication Appliqué an Classement (MICMAC) analysis to categorize the barriers in terms of their driving and dependence power.

Findings

The study has identified the key barriers to implementation of PjBL and presented an integrated model using ISM. Higher educational institutions need to pay attention to diagnose and overcome these hindrances for effective implementation of PjBL in their programmes.

Research limitations/implications

The study adopts a systematic way to model the relevant barriers to implementation of PjBL. The ISM-based model would help higher education institutions to prioritize the issues as the barriers are hierarchically structured. As the input to model development is based on the experts’ opinions, it may be biased, influencing the final output of the structural model.

Originality/value

The presentation of PjBL implementation barriers in the form of an ISM-based model is a new effort. The model would be useful to understand the barriers and overcome these for the successful implementation of PjBL in higher educational institutions.
Can labor productivity growth reduce carbon emission? Evidence from OECD countries and China
Authors: Chen Xueli , Ma Wanshu , Valdmanis Vivian
Published: December 2021

Purpose

The purpose of this study is to examine the challenges involved in the trade-offs of labor productivity and per capita carbon dioxide (CO2) emission.

Design/methodology/approach

In this research, we used a balanced dataset of 36 OECD countries and China between 1990 and 2018. We examined the relationship between labor productivity and per capita CO2 emission for OECD countries and China based on an Environmental Kuznets Curve (EKC) hypothesis. Further, the fixed effects model of estimation was employed to examine the impact of variables during the sample period and explore the relationship between predictor and outcome variables within an entity while controlling for all time-invariant differences.

Findings

This study confirmed the existence of the N-shape EKC hypothesis in 36 OECD countries and China. This implies that at the initial development stage, per capita CO2 emission increased with labor productivity; however, after reaching certain threshold, per capita CO2 emission began to fall with rising labor productivity. Then the per capita CO2 emission rises again when labor productivity continually increases.

Originality/value

In this study, we explored the dynamic association between labor productivity and per capita CO2 emissions for 36 OECD countries and China under the EKC framework from 1990 to 2018 by using the labor productivity and per capita CO2 emission as economic and environmental indicators of one country respectively. This study’s contribution showed the following: first, the empirical findings confirmed the N-shape relationship between labor productivity and per capita CO2 emissions for 36 OECD countries and China; second, the findings demonstrated that the association among the underlying variables by testing through the fixed effect model.
Analyzing complexities in the Brazilian soybean supply chain: a systems thinking and modeling approach
Authors: Filassi Monique , Oliveira Andréa Leda Ramos de , Elias Arun Abraham , Braga Marsola Karina
Published: December 2021

Purpose

This study aims to analyze the complexities of the Brazilian soybean supply chain (SSC) and develop strategic interventions to improve the origin system’s performance.

Design/methodology/approach

This study used stakeholder interviews to identify the SSC bottlenecks and determine and assess drivers of competitiveness. A methodological framework based on the systems thinking approach for developing long-term structural changes was used. The problem was structured using behavior over time graph and causal loop modeling to propose three investment strategies to solve the logistics problem in SSC.

Findings

This study highlights the gaps in coordination between stakeholders and the public sector regarding the public policy for infrastructure investment. Three strategic interventions were developed to address the agro-industrial logistical problem, namely, investment in storage, multimodal transport systems and improvements in existing transport infrastructure. To overcome transport and storage logistics limitations, the authors suggest different forms of partnerships, including public-private partnerships.

Research limitations/implications

This research is limited to evaluating an agricultural commodity (soybean) and does not include its by-products. The sample of stakeholders was limited and the boundary of analysis was Brazil. Nevertheless, the study showed how strategic interventions could be developed following a holistic analysis.

Practical implications

The proposed integrated approach illustrates the development of three strategic initiatives. It can be implemented by stakeholders, including the public sector, which is the basis for providing assertive long-term investments in Brazilian logistics.

Social implications

The SSC analysis could promote the implementation of systemically determined interventions and strategies. It could significantly improve the performance of agricultural systems and help the formulation of public policies aimed at rural development.

Originality/value

The use of system dynamics to identify intervention points is an essential contribution to mitigating the SSC’s hindrances. Moreover, the combining methodologies resulted in comprehensive intervention strategies.
Moderating role of power distance in the relationship between leader-leader exchange (LLX) and knowledge sharing: is feedback-seeking behavior a missing link?
Authors: Farooq Rayees , Tripathi Nachiketa
Published: December 2021

Purpose

This study aims to investigate the effect of leader-leader exchange (LLX) on knowledge sharing through feedback-seeking behavior. The study also explores the moderating role of power distance.

Design/methodology/approach

A cross-sectional data of 290 knowledge workers from manufacturing and service firms in India were taken as a sample of the study. The hypotheses were tested using confirmatory factor analysis, structural equation modeling and hierarchical regression.

Findings

The results showed that LLX positively affects knowledge sharing and feedback-seeking behavior mediates the relationship between LLX and knowledge sharing. Moreover, power distance does not moderate the relationship between LLX and knowledge sharing.

Originality/value

The present study one of its kind explores the relationship between LLX, feedback-seeking behavior, knowledge sharing and power distance.
A trade‐off between growth and hydraulic resilience against freezing leads to divergent adaptations among temperate tree species
Authors: Yin Xiao‐Han , Hao Guang‐You , Sterck Frank
Published: December 2021

In humid temperate forests, the occurrence of frequent freeze–thaw cycles (FTC) is a main factor limiting tree growth, as xylem embolism induced by FTC poses a serious threat to the hydraulic integrity of trees. A high resilience to hydraulic dysfunction involves the enhancement of embolism resistance and/or extra non‐structural carbohydrate (NSC) inputs for restoration of an impaired hydraulic system. However, potentially negative implications of such NSC allocation on tree growth have not yet been explored.

At a temperate forest site of northeast China, we studied xylem hydraulics and NSC contents in relation to winter embolism resilience in 15 sympatric broadleaf tree species belonging to three genera with relatively high species richness, but having distinct strategies in maintaining hydraulic integrity over the winter, that is, Acer species that generate positive stem and root pressures contributing to winter embolism refilling, Betula species that only generate root pressure and Populus species that do not generate positive pressure.

Acer and Betula species had higher soluble sugar contents in the dormant season and indeed had higher hydraulic resilience to FTC‐induced embolism but slower stem growth. Populus species had higher NSC contents during the growing season and their faster stem growth was also consistent with higher hydraulic efficiency and leaf photosynthetic rate. The positive correlation between tree trunk radial growth rate and hydraulic conductivity suggests that xylem water transport efficiency can be a fundamental basis for tree productivity due to a significant hydraulic‐photosynthetic coordination. The negative correlation between soluble sugar concentration in the dormant season and stem growth rate indicates that metabolic carbon costs for enhancing hydraulic resilience may compromise tree growth during the growing season.

Comparisons among Acer, Betula and Populus and the correlation analyses based on phylogenetic independent contrasts strongly support the existence of a trade‐off between hydraulic resilience against FTC‐induced embolism and growth rate among sympatric tree species under humid temperate climate conditions. This trade‐off has likely contributed to the sorting of temperate tree species and genera to different niches along environmental gradients with respect to freezing stress and interspecific competition.

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