bluuebunny/crossref_metadata_2025 huggingface dataset:
Human senataxin is a bona fide R-loop resolving enzyme and transcription termination factor
Authors: Hasanova Zdenka , Klapstova Veronika , Porrua Odil , Stefl Richard , Sebesta Marek
Published: August 2022

Prolonged pausing of the transcription machinery may lead to the formation of three-stranded nucleic acid structures, called R-loops, typically resulting from the annealing of the nascent RNA with the template DNA. Unscheduled persistence of R-loops and RNA polymerases may interfere with transcription itself and other essential processes such as DNA replication and repair. Senataxin (SETX) is a putative helicase, mutated in two neurodegenerative disorders, which has been implicated in the control of R-loop accumulation and in transcription termination. However, understanding the precise role of SETX in these processes has been precluded by the absence of a direct characterisation of SETX biochemical activities. Here, we purify and characterise the helicase domain of SETX in parallel with its yeast orthologue, Sen1. Importantly, we show that SETX is a bona fide helicase with the ability to resolve R-loops. Furthermore, SETX has retained the transcription termination activity of Sen1 but functions in a species-specific manner. Finally, subsequent characterisation of two SETX variants harbouring disease-associated mutations shed light into the effect of such mutations on SETX folding and biochemical properties. Altogether, these results broaden our understanding of SETX function in gene expression and the maintenance of genome integrity and provide clues to elucidate the molecular basis of SETX-associated neurodegenerative diseases.
Modeling tissue co-regulation to estimate tissue-specific contributions to disease
Authors: Amariuta Tiffany , Siewert-Rocks Katherine , Price Alkes L.
Published: August 2022

Integrative analyses of genome-wide association studies (GWAS) and gene expression data across diverse tissues and cell types have enabled the identification of putative disease-critical tissues. However, co-regulation of genetic effects on gene expression across tissues makes it difficult to distinguish biologically causal tissues from tagging tissues. While previous work emphasized the potential of accounting for tissue co-regulation, tissue-specific disease effects have not previously been formally modeled. Here, we introduce a new method, tissue co-regulation score regression (TCSC), that disentangles causal tissues from tagging tissues and partitions disease heritability (or covariance) into tissue-specific components. TCSC leverages gene-disease association statistics across tissues from transcriptome-wide association studies (TWAS), which implicate both causal and tagging genes and tissues. TCSC regresses TWAS chi-square statistics (or products of z-scores) on tissue co-regulation scores reflecting correlations of predicted gene expression across genes and tissues. In simulations, TCSC distinguishes causal tissues from tagging tissues while controlling type I error. We applied TCSC to GWAS summary statistics for 78 diseases and complex traits (averageN= 302K) and gene expression prediction models for 48 GTEx tissues. TCSC identified 21 causal tissue-trait pairs at 5% FDR, including well-established findings, biologically plausible novel findings (e.g. aorta artery and glaucoma), and increased specificity of known tissue-trait associations (e.g. subcutaneous adipose, but not visceral adipose, and HDL). TCSC also identified 17 causal tissue-trait covariance pairs at 5% FDR. For the positive genetic covariance between BMI and red blood cell count, brain substantia nigra contributed positive covariance while pancreas contributed negative covariance; this suggests that genetic covariance may reflect distinct tissue-specific contributions. Overall, TCSC is a precise method for distinguishing causal tissues from tagging tissues, improving our understanding of disease and complex trait biology.
A survey of patient and public perceptions and awareness of SARS-CoV-2-related risks among participants in India and South Africa
Authors: Mbamalu Oluchi , Surendran Surya , Nampoothiri Vrinda , Bonaconsa Candice , Edathadathil Fabia , Zhu Nina , Carter Vanessa , Lambert Helen , Tarrant Carolyn , Ahmad Raheelah , Brink Adrian , Steenkamp Ebrahim , Holmes Alison , Singh Sanjeev , Charani Esmita , Mendelson Marc
Published: August 2022

A cross-sectional survey was performed among the adult population of participating countries, India and South Africa. The purpose of this study was to explore perceptions and awareness of SARS-CoV-2-related risks in the relevant countries. The main outcome measures were the proportion of participants aware of SARS-CoV-2, and their perception of infection risks.

Self-administered questionnaires were used to collect data via a web- and paper-based survey over three months. For data capturing, Microsoft Excel was employed, and descriptive statistics used for presenting data. Pearson’s Chi-squared test was used to assess relationships between variables, and a p-value less than 0.05 was considered significant.

There were 844 respondents (India: n=660, South Africa: n=184; response rate 87.6%), with a 61.1% vs 38.3% female to male ratio. Post-high-school or university education was the lowest qualification reported by most respondents in India (77.3%) and South Africa (79.3%). Sources of information about the pandemic were usually media and journal publications (73.2%), social media (64.6%), family and friends (47.7%) and government websites (46.2%). Most respondents correctly identified infection prevention measures (such as physical distancing, mask use), with 90.0% reporting improved hand hygiene practices since the pandemic. Hesitancy or refusal to accept the SARS-CoV-2 vaccine was reported among 17.9% and 50.9% of respondents in India and South Africa, respectively. Reasons cited included rushed vaccine development and the futility of vaccines for what respondents considered a self-limiting flu-like illness.

Respondents identified public health promotion measures for SARS-CoV-2. Reported hesitancy to the up-take of SARS-CoV-2 vaccines was much higher in South Africa. Vaccination campaigns should consider robust public engagement and contextually fit communication strategies with multimodal, participatory online and offline initiatives to address public concerns, specifically towards vaccines developed for this pandemic and general vaccine hesitancy.
Effects of stimulus timing on the acquisition of an olfactory working memory task in head-fixed mice
Authors: Reuschenbach Josefine , Reinert Janine K , Fukunaga Izumi
Published: August 2022

Knowing what factors affect the acquisition of a behavioural task is central to understanding the mechanisms of learning and memory. It also has practical implications, as animal behavioural experiments used to probe cognitive functions often require long training durations. Delayed Match (or Non-Match)-to-Sample (DMS/DNMS) tasks are relatively complex tasks used to study working memory and sensory perception, but their use in the mouse remains hampered by the lengthy training involved. In this study, we assessed two aspects of stimulus timing on the acquisition of an olfactory DNMS task: how the sample-test odour delay durations and the reward timing affect the acquisition rate. We demonstrate that head-fixed mice learn to perform an olfactory DNMS task more quickly when the initial training uses a shorter sample-test odour delay without detectable loss of generalisability. Unexpectedly, we observed a slower task acquisition when the odour-reward interval was shorter. This effect was accompanied by a shortening of reaction times and more frequent sporadic licking. Analysis of this result using a drift-diffusion model indicated that a primary consequence of early reward delivery is a lower decision bound. Since an accurate performance with a lower decision bound requires greater discriminability in the sensory representations, this may underlie the slower learning rate with early reward arrival. Together, our results reflect the possible effects of stimulus timing on stimulus encoding and its consequence on the acquisition of a complex task.
Underreported in-water behaviours of the loggerhead sea turtle:Getting buried in the sand
Authors: Papafitsoros Kostas
Published: August 2022

In this short report, we provide a direct evidence that loggerhead sea turtlesCaretta carettaare capable of partially burying themselves in the sand by actively moving their front flippers and stirring the sea bottom sediment. In particular, we report the cases of three male loggerhead sea turtles from Zakynthos island, Greece, which, after obtaining a resting position on a sandy spot at the sea bottom, they actively performed digging and stirring movements with their front flippers, resulting to the sand getting raised at the sea column. When the sand settled back, the turtles ended up half-buried and camouflaged. To our current knowledge, this self-burying behaviour has not been described in the literature.
Fighting isn’t sexy in lekking Greater Sage-grouse (Centrocercus urophasianus)
Authors: Snow Samuel S. , Patricelli Gail L. , Butts Carter T. , Krakauer Alan H. , Perry Anna C. , Logsdon Ryane , Prum Richard O.
Published: August 2022

In lekking systems, females can observe both male courtship displays and fights. It has been theorized that male-male agonism may function as a display, giving females more information about mate quality. However, males in many species, such as Greater Sage-grouse, often fight when females are absent, and can even attack during copulation attempts in seeming conflict with females’ choices.

Traditional correlational approaches are inadequate to distinguish the underlying mechanisms of social interaction and can result in misleading associations between fighting and mating events. Using observations from a wild population, we posit a novel Relational Event Model that incorporates temporal dependencies of events among a network of individuals. We investigate how fighting among male sage-grouse predicts events such as future fights, copulation solicitations, and interrupted copulations.

Our analysis reveals that fighting’s primary function is not to impress females. Indeed, males are less likely to start and more likely to leave fights with females present, plausibly to avoid entanglement in conflict that reduces availability to mate. Moreover, being drawn into these latter viscous cycles of combat and retribution constitutes a significant risk associated with initiating attacks on other males. However, fighting serves other roles, e.g., to deter copulation interruptions and rebuff competitors. Our findings suggest that social systems that regulate conflict and promote females’ choice based on display are likely fundamental to the stable evolution of leks.
Movement data link phenotypic traits to individual fitness in a nocturnal predator
Authors: Becciu Paolo , Séchaud Robin , Schalcher Kim , Plancherel Céline , Roulin Alexandre
Published: August 2022

Recent biologging technology reveals hidden life and breeding strategies of nocturnal animals. Combining animal movement patterns with individual characteristics and landscape features can uncover meaningful behaviours that directly influence fitness. Consequently, defining the proximate mechanisms and adaptive value of the identified behaviours is of paramount importance. Breeding female barn owls (Tyto alba), a colour-polymorphic species, recurrently visit other nest boxes at night. We described and quantified this behaviour for the first time, linking it with possible drivers, and individual fitness. We GPS-equipped 178 breeding pairs of barn owls from 2016 to 2020 in western Switzerland during the chick rearing phase. We observed that 65% of breeding females tracked were (re)visiting nest boxes while still carrying out their first brood. We modelled their prospecting parameters as a function of partner-, individual- and brood-related variables, and found that female feather eumelanism predicted the emergence of prospecting behaviour (less melanic females are usually prospecting), while increasing male parental investment increased female exploratory efforts. Ultimately, females would revisit a nest more often if they had used it in the past and were more likely to lay a second clutch afterwards, consequently having higher annual fecundity than non-prospecting females. Despite these apparent immediate benefits, they did not fledge more chicks. We highlight how phenotypic traits can be related to movement patterns and individual fitness through biologging associated with long-term field monitoring.
Dynamic modelling and analysis of autophagy in the clearance of aggregated α-synuclein in Parkinson’s disease
Authors: Yang Bojie , Yang Zhuoqin , Liu Heng
Published: August 2022

The widely-accepted hallmark pathology of Parkinson’s disease (PD) is the presence of Lewy bodies (LB) with characteristic abnormal aggregated α-synuclein (αSyn). Growing physiological evidences suggest that there is a pivotal role for the autophagy-lysosome pathway in the clearance of misfolded αSyn (αSyn*) for maintaining homeostasis and neural cell function. In this work, we establish a new mathematical model for αSyn* degradation through the autophagy pathway. The qualitative simulations discover the tri-stability phenomena and dynamical behaviors of αSyn*, i.e., the coexistence of three stable steady states, in which the lower, medium and upper steady states correspond to the healthy, critical and diseased stages of pathological mechanism of PD, respectively. Diverse analyses on codimension-1 and -2 bifurcations suggest that autophagy can control the switches among the stable steady states for the aggregation of αSyn*. It is also found that the double negative crosstalk feedback between autophagy and apoptosis is important to the robustness of tri-stability of αSyn* for this biodynamic system. Our novel results may be valuable for making further therapeutic strategies in prevention and treatment for PD.

Author summary

αSyn* is one of the most and primary remarkable targets for the universal neurodegenerative disease of PD. Efficient clearance mechanism of autophagy, contains a lot of molecular components to maintain the cellular homeostasis and cell renewal, could be the possible therapy for PD. Understand the complexity of autophagy in degrading αSyn* requires the integration of both theoretical and experimental points of view. Here, we have proposed a novel mathematical model that analyses the temporal and dynamic behaviors of the biosystem for autophagy degrades αSyn* to access PD states. The model explains that the tri-stability is of particularly relevance to this biosystem that switch among the healthy, critical and disease states, and captures that the critical intermedium state exits for preventing the system transform healthy to disease state directly, and further illustrates that the molecular signaling feedback loops of autophagy may be important for the robustness of tri-stability. Our work deepens the researches of PD by uncovering the important buffering medium state and providing promising potential therapeutic insights.
Myosin-dependent partitioning of junctional Prickle2 toward the anterior vertex during planar polarization of Xenopus neuroectoderm
Authors: Chu Chih-Wen , Davidson Lance A.
Published: August 2022

Planar cell polarity (PCP) of tissues is established by mutually exclusive partitioning of transmembrane proteins Frizzled and Vangl with their respective binding partners, Dishevelled and Prickle. While the amplification and maintenance of this pattern have been well studied, it remains unclear how the anterior-biased protein localization is initiated. Moreover, PCP protein complexes are located at adherens junctions and their polarization requires the activity of non-muscle myosin II (NMII), but how NMII contributes to PCP is not fully understood. Here we analyze time-lapse images of mNeonGreen-tagged Prickle2 (Pk2) in mid-gastrula stage Xenopus presumptive neuroectoderm and demonstrate that Pk2 puncta move along bicellular apical junctions in a biased manner toward the anterior vertex, where the Vangl-Pk complexes are normally enriched. In addition, length changes of bicellular junction segments flanking each Pk2 punctum are often different from each other, and appear more dynamic near the vertices, suggesting that Pk2 movement is driven by intrinsic junction heterogeneity. Reducing NMII activity eliminates the anterior movement, and surprisingly, increases the motility of Pk2 punta. By assessing the correlation between Pk2 movement and the relative positioning of each Pk2 punctum along apical junctions, we uncovered that NMII activity is required for the anterior Pk2 movement by maintaining the elongation of posterior junction segment while inhibiting Pk2 movement toward both vertices flanking the junctions. Our findings provide the first evidence of biased partitioning of junctional PCP proteins toward the anterior vertex and support the hypothesis that NMII activity facilitates Pk2 polarization not via a direct transport but by regulating intrinsic dynamics of the bicellular junction.
Higher in vitro mucin degradation, but no increased paracellular permeability by faecal water from Crohn’s disease patients
Authors: Becker Heike E.F. , Kameli Nader , Rustichelli Alice , Heijnens Britt A.M. , Stassen Frank , Penders John , Jonkers Daisy M.A.E.
Published: August 2022

Background

Crohn’s disease (CD) is a chronic inflammatory gastro-intestinal condition with variable disease course. Impaired barrier function and microbial dysbiosis are associated with disease onset and exacerbations. We hypothesized that perturbed microbial activity may contribute to the impaired barrier function in CD. Therefore, this study aimed to examine the impact of faecal bacterial products of active and remissive CD patients, and healthy controls (HC) on mucin degradation and epithelial barrier function in vitro.

Methods

Six HC and twelve CD patients were included. Disease activity was determined by endoscopy. Fecal water (FW) and bacterial membrane vesicles (MVs) from fresh fecal samples were applied on mucin agar to determine mucin degradation and on differentiated Caco-2 cell monolayers to assess transepithelial electrical resistance (TEER) and paracellular junction stability. Relative abundances of fecal bacterial genera, which may be associated mucin degradation, were evaluated using 16S rRNA gene amplicon sequencing.

Results

FW-induced mucin degradation was higher in CD samples as compared to HC (p<0.01), but was not linked to specific bacterial relative abundances. FW resulted in 78-87% decrease of TEER in three of the remissive (p<0.001) but not the active CD or HC samples. MVs did not induce mucin degradation or epithelial barrier disruption.

Conclusion

The higher mucin degradation capacity of CD-derived FW might indicate contributions of microbial products to CD pathophysiology and warrants further investigation. Moreover, the altered epithelial resistance in some individuals is not due to paracellular disruption.

Key Messages

What is already known? Intestinal microbial dysbiosis and mucosal barrier dysfunction are important contributors to Crohn’s disease aetiology and disease exacerbations.

What is new here? The faecal microbial secretome of Crohn’s disease patients has a higher mucin degradation capacity as compared to the secretome of healthy subjects.

How can this study help patient care? The increased mucin degradation based on the microbial secretome may be a new target for the development of complementary, microbiome-based therapy in Crohn’s disease.

Microbial dysbiosis and intestinal barrier dysfunction can impact Crohn’s disease course. This translational study found higher mucin degradation, but no epithelial barrier disruption, by the faecal microbial secretome of (active) Crohn’s disease patients, as compared to healthy controls.
Track-by-Day: A standardized approach to estrous cycle monitoring in biobehavioral research
Authors: Raimondi Gianna M. , Eng Ashley K. , Kenny Murphy P. , Britting Madison A. , Ostroff Linnaea E.
Published: August 2022

Despite known sex differences in brain function and incidence of neurological disorders, female subjects are routinely excluded from preclinical neuroscience research, particularly behavioral studies in rats. A common rationale for excluding females is that the hormone fluctuations of the estrous cycle will increase variability in experimental data. Accounting for the estrous cycle as an experimental variable requires expert knowledge of cycle tracking methods, which presents a barrier to widespread inclusion of female subjects. Conventional tracking relies on qualitative interpretation of vaginal cytology smears, and the subjective nature of this approach combined with a lack of reporting standards likely underlies the conflicting literature on estrous cycle effects on behavior. The estrous cycle is traditionally divided into stages based on cytology, but most stages do not directly reflect hormonal events and are therefore of limited relevance to neuroscience experiments. Here we present a simple, streamlined approach to estrous cycle monitoring in rats that eliminates subjective staging. Our method instead indexes the days of the estrous cycle to the one event that is unambiguously reflected in vaginal cytology – the pre-ovulatory surge in 17β-estradiol and subsequent epithelial cornification. With this tracking method, we demonstrate that cycle length is robustly regular across conditions. We quantified long-term memory in a Pavlovian fear conditioning experiment and uterine histology in a large cohort of rats, and found that grouping subjects by day was more sensitive in detecting cycle effects than grouping by traditional cytology staging. We present several datasets demonstrating the logic and applicability of our method, and show that, in the Track-by-Day framework, the cycle is highly regular and predictable in the vast majority of rats across a range of experimental conditions.
Variability in training unlocks generalization in visual perceptual learning through invariant representations
Authors: Manenti Giorgio L. , Dizaji Aslan Satary , Schwiedrzik Caspar M.
Published: August 2022

Stimulus and location specificity are long considered hallmarks of visual perceptual learning. This renders visual perceptual learning distinct from other forms of learning, where generalization can be more easily attained, and unsuitable for practical applications, where generalization is key. Based on hypotheses derived from the structure of the visual system, we test here whether stimulus variability can unlock generalization in perceptual learning. We train subjects in orientation discrimination, while we vary the amount of variability in a task-irrelevant feature, spatial frequency. We find that independently of task difficulty, this manipulation enables generalization of learning to new stimuli and locations, while not negatively affecting the overall amount of learning on the task. We then use deep neural networks to investigate how variability unlocks generalization. We find that networks develop invariance to the task-irrelevant feature when trained with variable inputs. The degree of learned invariance strongly predicts generalization. A reliance on invariant representations can explain variability-induced generalization in visual perceptual learning, suggests new targets for understanding the neural basis of perceptual learning in high-order visual cortex, and presents an easy to implement modification of common training paradigms that may benefit practical applications.
Detection and typing of plasmids in Acinetobacter baumannii using rep genes encoding replication initiation proteins
Authors: Lam Margaret M.C. , Koong Jonathan , Holt Kathryn E. , Hall Ruth M. , Hamidian Mehrad
Published: August 2022

Plasmids found in Acinetobacter species contribute to the spread of antibiotic resistance genes. They appear to be largely confined to this genus and cannot be typed with available tools and databases. Here, a method for distinguishing and typing these plasmids was developed using a curated, non-redundant set of 621 complete sequences of plasmids from Acinetobacter baumannii. Plasmids were separated into three groups based on the Pfam domains of the encoded replication initiation (Rep) protein and a fourth group that lack an identifiable Rep protein. The rep genes of each Rep-encoding group (n=13 Rep_1, n=107 RepPriCT_1, n=351 Rep_3) were then clustered using a threshold of >95% nucleotide identity to define 80 distinct types. Five Rep_1 subgroups, designated R1_T1 to R1-T5, were identified and a sixth reported recently was added. Each R1 type corresponded to a conserved small plasmid sequence. The RepPriCT_1 plasmids fell into 5 subgroups, designated RP-T1 to RP-T5 and the Rep_3 plasmids comprised 69 distinct types (R3-T1 to R3-T69). Three R1, 2 RP and 32 R3 types are represented by only a single plasmid. Over half of the plasmids belong to the four most abundant types: the RP-T1 plasmids (n=97), which include conjugation genes and are often associated with various acquired antibiotic resistance genes, and R3-T1, R3-T2 and R3-T3 (n=95, 30 and 45, respectively). To facilitate typing and the identification of plasmids in draft genomes using this framework, we established the Acinetobacter Typing database containing representative nucleotide and protein sequences of the type markers (https://github.com/MehradHamidian/AcinetobacterPlasmidTyping).

IMPORTANCE

Though they contribute to the dissemination of genes that confer resistance to clinically important carbapenem and aminoglycoside antibiotics used to treat life-threatening Acinetobacter baumannii infections, plasmids found in Acinetobacter species have not been well studied. As these plasmids do not resemble those found in other Gram-negative pathogens, available typing systems are unsuitable. The plasmid typing system developed for A. baumannii plasmids with an identifiable rep gene will facilitate the classification and tracking of sequenced plasmids. It will also enable the detection of plasmid-derived contigs present in draft genomes that are widely ignored currently. Hence, it will assist in the tracking of resistance genes and other genes that affect survival in the environment, as they spread through the population. As identical or similar plasmids have been found in other Acinetobacter species, the typing system will also be broadly applicable in identifying plasmids in other members of the genus.
Effects of interspecies interactions on marine community ecosystem function
Authors: Daniels Michael , Stubbusch Astrid K.M. , Held Noelle A. , Schubert Olga T. , Ackermann Martin
Published: August 2022

Microbial communities perform key ecosystem processes collectively. One such process is the degradation of carbohydrate polymers, which are the dominant pool of organic carbon in natural environments. Carbohydrate polymers are often degraded in a stepwise manner. Individual steps are performed by different microbial species, which form trophic cascades with carbon polymers at the bottom and fully oxidised carbon at the top. It is widely believed that these trophic cascades are hierarchically organised, where organisms at each level rely on organisms at the levels below. However, whether and how the higher-level organisms can also affect processes at the lower levels is not well understood. Here we studied how carbohydrate polymer degradation mediated by secreted enzymes is affected by species at higher trophic levels, i.e., species that cannot produce the enzymes for polymer degradation but can grow in presence of the polymer degraders. We used growth and enzyme assays in combination with transcriptomics to study how chitin degradation by a number of Vibrio strains is affected by the presence of different cross-feeders that consume metabolic by-products. We found that interactions between the degraders and cross-feeders influence the rate of chitin degradation by the community. Furthermore, we show that this is a result of changes in chitinase expression by degraders. Overall, our results demonstrate that interactions between species can influence key ecosystem functions performed by individuals within microbial communities. These results challenge the perspective that trophic cascades based on metabolically coupled microbial communities are unidirectional and provide mechanistic insights into these downstream interactions.
Structural analysis unravels the functional promiscuity of Quinolone synthase-mediated polyketide biosynthesis in Aegle marmelos Correa
Authors: Vijayanathan Mallika , Abhinav KV , Bandyopadhyay Debashree , Mahendran Kozhinjampara R , Sharaf Abdoallah , Pillai M Radhakrishna , Soniya EV
Published: August 2022

Quinolone synthase from Aegle marmelos (AmQNS) is a type III polyketide synthase that yields therapeutically effective quinolone and acridone compounds. Based on the high-resolution protein structure of AmQNS, this study provided a mechanistic explanation of the structure to synthetic selectivity. Additionally, it displays the comparatively wide active site entry that allows the catalytic pocket to accommodate bulky substrates, which affects the enzyme catalysis. We also develop a model framework for comprehending the structural constraints on ketide insertion, and postulate that AmQNS synthetic diversity is owing to its steric and electrostatic selectivity, which allows it to bind to a variety of core substrates. We further establish that AmQNS is structurally biased toward quinolone synthesis and only synthesizes acridone when malonyl-CoA concentrations are significantly high. In a nutshell, we anticipate that addressing the structural and molecular underpinnings of AmQNS–substrate interaction in terms of its high selectivity and specificity can aid in the development of numerous novel compounds. Besides, the approaches can also be expanded to other potential enzymes, which will help the pharmaceutical sector by expanding the pool of potential medication leads.
Oligomeric polymorphism of HIV-1 Vpu protein in lipid environment and in solution
Authors: Majeed Saman , Adetuyi Oluwatosin , Islam Md Majharul , Zhao Bo , Georgieva Elka R.
Published: August 2022

The HIV-1 encoded protein Vpu forms an oligomeric ion channel/pore in membranes and interacts with multiple host proteins to support virus lifecycle. However, Vpu molecular mechanisms are currently not well understood. The structures of full-length Vpu in its monomeric and oligomeric forms are unknown, although both the monomer and oligomer are deemed important. Here, we report on the diversity of Vpu oligomeric structures and how the environment affects the Vpu oligomer formation. We produced a uniquely designed MBP-Vpu chimera protein in E. coli in soluble form. We subjected this protein to analytical size exclusion chromatography (SEC) and negative staining electron microscopy (nsEM). Strikingly, we found that MBP-Vpu forms stable oligomers in solution, presumably driven by Vpu transmembrane domain self-association. Our coarse modeling suggests that these oligomers are pentamers, in agreement with the pentameric membrane-bound Vpu. To the best of our knowledge, this is the first observation of Vpu self-association out of lipid membrane environment. We further found that MBP-Vpu oligomer stability decreases when the protein was reconstituted in lipid membrane mimetics, such as β-DDM, and mixtures of lyso PC/PG or DHPC/DHPG—In these cases significant oligomer heterogeneity was observed with oligomeric order lesser than that of MBP-Vpu oligomer in solution, but larger oligomers were observed as well. Importantly, we found that in lyso PC/PG, above certain protein concentration, MBP-Vpu forms linear array-like structures, which is also novel. Thus, our studies provide unique information about Vpu protein quaternary organization by capturing multiple Vpu oligomeric structures, which we believe are physiologically relevant.
Bis[3,5-difluoro-2-(pyridin-2-yl)phenyl](4,4′-dimethoxy-2,2′-bipyridine)iridium(III) hexafluoridophosphate
Authors: Shevlin Madelyn R. , Stumbo Emily E. , McMillen Colin D. , Pienkos Jared A.
Published: August 2022

The title cyclometalated distorted octahedral iridium complex, [Ir(C11H6F2N)2(C12H12N2O2)]PF6, exhibits elongated Ir—N bonds to the dimethoxy bipyridine ligand [2.128 (3) and 2.136 (3) Å] where these nitrogen atoms are trans to the Ir—C bonds of the two cyclometalating difluorophenylpyridine ligands. The angles between the mean planes of the phenyl and pyridyl fragments within the individual ligands range from 3.5 (2) to 11.4 (2)° to deviate slightly from coplanarity.
Critical factors in awakening the slumbering collections: a study based on XGBoost
Authors: Zhang Xiaoxiao , Shi Guoliang , Jin Qiupan
Published: August 2022

Purpose

The purpose is to explore the essential reasons for the differences between book awakening phenomena, to develop the critical factors in awakening the slumbering collections and to provide a reliable basis for maximizing book value and optimizing collection allocation.

Design/methodology/approach

The research employs the integrated learning algorithm XGBoost to measure driving factors. In the process of book circulation, the characteristics of collections and readers are worthy of attention. Therefore, this study also carries out feature selection and model construction from the two dimensions of books and readers.

Findings

The results show that reader features have a stronger impetus for the collection awakening phenomenon than collection features. Among reader features, education level, gender and major subject are the main factors, which are followed closely by the activity level; among collection features, publication date and price are the main driving factors. The indicators of book popularity are not significant, whose effect on the phenomenon of collection awakening is almost negligible.

Originality/value

This study aims to augment the theory of zero circulation from the theoretical level and, for the first time, seeks to define the phenomenon of collection awakening. This study attempts to present novel ideas for research in the field of libraries and to provide references for optimizing collection and maximizing the value of books.
Toward a better understanding of the attitude–behavior gap in organic food conative loyalty: a moderation and moderated mediation analysis
Authors: Anisimova Tatiana , Weiss Jan
Published: August 2022

Purpose

Previous research has found mixed evidence of an attitude–behavior gap in organic food consumption. However, the complex mechanisms underlying this gap warrant further investigation. The purpose of this study is to examine the role of word-of-mouth (WOM), trust, and involvement in the relationship between consumer organic food attitudes and conative loyalty. The Theory of Planned Behavior (TPB) was used as underlying framework for modeling our conceptualized arguments.

Design/methodology/approach

A moderation and moderated mediation analysis was performed on a cross-sectional sample of 1,011 Australian organic food consumers.

Findings

The results support the TPB-inspired moderated-mediation model. Specifically, the authors found moderated mediation effects of WOM, trust, and involvement on conative loyalty via attitudes toward organics.

Research limitations/implications

The cross-sectional research design and the focus solely on Australian consumers constitute limitations of this study.

Practical implications

The authors' findings imply that an analysis of the attitude–behavior gap should go beyond the testing of contingent consistency hypotheses and instead combine moderation and mediation mechanisms to better model consumer decision-making leading to conative loyalty. Practitioners would face a resource challenge when targeting low-trust, low-involvement, and low-WOM consumers as developing conative loyalty of these segments would require a longer-term approach through building favorable attitudes toward organic foods.

Originality/value

This study is one of the first to demonstrate the potential of examining the attitude–behavior gap in the organic food context through a moderated mediation lens in explaining the dynamics of conative loyalty.
Gender roles or gendered goals? Women's return to rural family business
Authors: Gashi Nulleshi Shqipe , Kalonaityte Viktorija
Published: August 2022

Purpose

This paper aims to add to the theorization of the gender dynamic in rural areas by investigating the motives of women who join their family firm (or their spouse's family firm) and thereby defy the demographic trend of rural flight. The context of this study is the depopulation of rural areas with the closing of basic services and relocation of the younger population, and educated women in particular, to urban areas. Consequently, rural family businesses risk failing to find successors and suffering forced closure or relocation. The empirical site of the study is rural family firms in Sweden, a context characterized by a high level of gender equality in legislation and culture but gender-conservative business structures in rural regions.

Design/methodology/approach

The empirical case in this paper builds on a qualitative study of nine (9) life course narratives of women entrepreneurs in a rural region of Southern Sweden who have returned to rural areas to join their family business. The authors follow the view established by gender scholars that women are active agents in navigating their lives, and their life story narratives offer insight into the considerations that inform their choice to stay or return to rural locations. In Sweden, the setting for the study, gender equality is widely supported by legislation, policy and institutional frameworks and popular understanding of gender relations. In contrast to the gender-progressive policies of Sweden at large, women's entrepreneurship in rural regions of Sweden tends to follow traditional gender hierarchies and face similar constraints as in rural areas of other countries. The juxtaposition of these competing sets of ideals makes Sweden an important and interesting place to study and draw insights from the experiences of women entrepreneurs.

Findings

The findings reveal that women who choose to join rural family firms view them primarily in a positive light and see this choice as aligned with their need for professional flexibility and assertiveness, rewarding relationships, and a calm, secure, well-balanced life. Theoretically, the study implies that women choosing to engage in rural family firms seek non-material benefits, such as work–life balance and social support, and may be driven in part by a sense of psychological ownership that extends to the rural community.

Originality/value

The findings provide novel insights on women as active agents in navigating their lives and the intrinsic (e.g. alignment of personal values) and extrinsic (e.g. community support) motives that inform their decisions. The study also raises questions regarding how women perceive themselves as “fitting in” to rural settings and to what extent the sense of security within these settings that the women describe may be contingent upon factors such as their families' embeddedness within the community as well as their conformity to the local social norms.
Would you share that? How the intensity of violent and sexual humor, gender and audience diversity affect sharing intentions for online advertisements
Authors: Freeman Richard , Marder Ben , Gorton Matthew , Angell Rob
Published: August 2022

Purpose

The purpose of this study is to understand the effect of increasing the intensity of sexual or violent content on consumer responses to online video advertisements, with a particular emphasis on sharing intentions.

Design/methodology/approach

The paper uses a between-subjects experimental design across two studies using new to the world online video advertisements as stimuli.

Findings

Study 1 finds that increasing the intensity of sexual and violent humor improves advertisement effectiveness amongst men but leads to significantly more negative attitudes toward the advertisement and brand amongst women. Study 2 identifies gender and humor type as moderators for sharing intentions in the presence of audience diversity. While men are more likely to publicly share sexual and violent humor advertisements, social anxiety mediates intentions to share sexual humor advertisements in the presence of greater audience diversity.

Practical implications

The paper offers insights to practitioners regarding the use of risqué forms of humor as part of a digital marketing strategy.

Originality/value

Drawing on and extending benign violation theory, the paper introduces and verifies a theoretical model for understanding consumer responses to the use of risqué forms of humor in online advertisements. It identifies how audience diversity affects sharing intentions for sexual and violent humor-based advertisements on social media.
Knowledge ecosystem of financial markets: a new perspective on alleviating the supply-demand contradiction of the rural finance in the post-COVID-19 era
Authors: Yang Yimin , Su Yuefeng , Yang Lulu , Zeng Xiongwang
Published: August 2022

Purpose

This paper aims to establish a systematic cognition to alleviate the supply–demand contradiction in rural financial markets from an integrated perspective of knowledge management and proposes the concept of rural financial knowledge ecosystem (RFKE) to encourage multifaceted solutions.

Design/methodology/approach

The authors qualitatively describe the process that the knowledge management dilemmas cause the supply–demand contradiction in the rural finance and further summarize a systematic methodology from three dimensions: the knowledge subject, the knowledge environment and the knowledge ecology.

Findings

The authors list four types of knowledge management dilemmas leading to the supply–demand contradiction in the rural finance, i.e. the weak knowledge sharing, the poor knowledge flow, the slow knowledge updating and the imperfect knowledge environment. Meanwhile, the RFKE model consisting of the ecological subject, the ecological environment and the ecological regulation is also presented.

Research limitations/implications

The role of knowledge management in improving the allocation of financial resources to various rural financial market participants (government, rural financial institutions, farmers, agricultural enterprises, etc.).

Originality/value

The authors creatively give the RFKE model, which complements and enriches the theory of knowledge management. Meanwhile, relevant management practices are urgently needed under the macro circumstance of the COVID-19 pandemic and the rural revitalization in China.
Why and how targets’ negative workplace gossip exhort knowledge hiding? Shedding light on organizational justice
Authors: Khan Abdul Gaffar , Li Yan , Akram Zubair , Akram Umair
Published: August 2022

Purpose

Extant scholars identified negative workplace gossip as a social stressor that negatively influences employees’ behavior and attitude. Despite the burgeoning interest in workplace stressors, limited studies have explored how the detrimental consequences of targets’ perceived negative workplace gossip spur their emotions and behaviors. Grounding on conservation of resources and ego depletion theories, this study aims to investigate why and how targets’ negative workplace gossip may contribute to trigger knowledge hiding. Specifically, the authors explore the underlying mechanism of personal ego depletion and boundary conditions of organizational justice to shed new light on the above process.

Design/methodology/approach

Using two time-wave survey, the authors collected 340 sample data from employees working in high-tech companies of China. Hierarchical regression analysis was used to examine hypothesized relationships of moderated mediation model.

Findings

The empirical results revealed that negative workplace gossip exacerbates knowledge hiding by increasing personal ego depletion. Furthermore, through testing moderated mediation model, the results showed that organizational justice (i.e. distributive and procedural justice) with the low presence moderates the stronger strength of the linkage between negative workplace gossip and personal ego depletion, and likewise, it also moderates the stronger effect of negative workplace gossip on knowledge hiding via personal ego depletion.

Practical implications

This study recommends several guidelines for managers and practitioners to mitigate negative gossip by strengthening organizational justice.

Originality/value

This study first enriches novel understanding in the literature between negative workplace gossip and knowledge hiding by using a new emotional mechanism (i.e. personal ego depletion). This research also contributes new insights by incorporating contextual boundary conditions (i.e. organizational justice) that have not been yet researched on negative gossip and knowledge hiding linkage.
Hiring for gender diversity in tech
Authors: Ly-Le Tuong-Minh
Published: August 2022

Purpose

Gender diversity, or in-diversity, has long been a problem in the tech industry. Until now, significant gaps and barriers still exist. This paper examines how recruitment practices within the technology sector can contribute to gender inequality and how recruitment practices can be improved to support a gender-diverse organization.

Design/methodology/approach

This paper adopted library research and case study as papers' methodologies.

Findings

There are many benefits of gender diversity, including better performance, better financial returns, and lower volatility. However, most tech companies do not make diversity a priority, and usually display conscious or unconscious gender biases. Some of the recommendations to overcome this diversity issue are to make diversity a goal, offer unconscious bias training, and expand recruitment efforts.

Practical implications

The findings imply that companies not pursuing a diverse workforce are in danger of experiencing lags in innovation and could be left behind. The findings also show that a technology company can increase the diversity of the company's workforce by applying practices that have already proven to be successful.

Originality/value

This paper confirms that gender parity is not just a social mission nor is gender parity solely a public relations initiative to improve a company's image. Technology companies must be continually innovating to thrive in companies' highly competitive and rapidly changing industry.