bluuebunny/crossref_metadata_2025 huggingface dataset:
Operating principles of circular toggle polygons
Authors: Hati Souvadra , Duddu Atchuta Srinivas , Jolly Mohit Kumar
Published: November 2020

Decoding the dynamics of cellular decision-making and cell differentiation is a central question in cell and developmental biology. A common network motif involved in many cell-fate decisions is a mutually inhibitory feedback loop between two self-activating ‘master regulators’ A and B, also called as toggle switch. Typically, it can allow for three stable states – (high A, low B), (low A, high B) and (medium A, medium B). A toggle triad – three mutually repressing regulators A, B and C, i.e. three toggle switches arranged circularly (between A and B, between B and C, and between A and C) – can allow for six stable states: three ‘single positive’ and three ‘double positive’ ones. However, the operating principles of larger toggle polygons, i.e. toggle switches arranged circularly to form a polygon, remain unclear. Here, we simulate using both discrete and continuous methods the dynamics of different sized toggle polygons. We observed a pattern in their steady state frequency depending on whether the polygon was an even or odd numbered one. The even-numbered toggle polygons result in two dominant states with consecutive components of the network expressing alternating high and low levels. The odd-numbered toggle polygons, on the other hand, enable more number of states, usually twice the number of components with the states that follow ‘circular permutation’ patterns in their composition. Incorporating self-activations preserved these trends while increasing the frequency of multistability in the corresponding network. Our results offer insights into design principles of circular arrangement of regulatory units involved in cell-fate decision making, and can offer design strategies for synthesizing genetic circuits.
Genome Wide Association Studies on 7 Yield-related Traits of 183 Rice Varieties in Bangladesh
Authors: Roy Nilanjan , Kabir Acramul Haque , Zahan Nourin , Mouna Shahba Tasmiya , Chakravarty Sakshar , Rahman Atif Hasan , Bayzid Md. Shamsuzzoha
Published: November 2020

Motivation

Rice genetic diversity is regulated by multiple genes and is largely dependent on various environmental factors. Uncovering the genetic variations associated with the diversity in rice populations is the key to breed stable and high yielding rice varieties.

Results

We performed Genome Wide Association Studies (GWAS) on 7 rice yielding traits (grain length, grain width, grain weight, panicle length, leaf length, leaf width and leaf angle) based on a population of 183 rice landraces of Bangladesh. Our GWA studies reveal various chromosomal regions and candidate genes that are associated with different traits in Bangladeshi rice varieties. Noteworthy was the recurrent implication of chromosome 10 in all three grain shape related traits (grain length, grain width, and grain weight), indicating its pivotal role in shaping rice grain morphology. Our study also underscores the involvement of transposon gene families across these three traits. For leaf related traits, chromosome 10 was found to harbor regions that are significantly associated with leaf length and leaf width. The results of these association studies support previous findings as well as provide additional insights into the genetic diversity of rice.

Conclusions

This is the first known GWAS study on various yield-related traits in the varieties ofOryza sativaavailable in Bangladesh – the fourth largest rice-producing country. We believe this study will accelerate rice genetics research and breeding stable high-yielding rice in Bangladesh.
A probabilistic model for indel evolution: differentiating insertions from deletions
Authors: Loewenthal Gil , Rapoport Dana , Avram Oren , Moshe Asher , Itzkovitch Alon , Israeli Omer , Azouri Dana , Cartwright Reed A. , Mayrose Itay , Pupko Tal
Published: November 2020

Insertions and deletions (indels) are common molecular evolutionary events. However, probabilistic models for indel evolution are under-developed due to their computational complexity. Here we introduce several improvements to indel modeling: (1) while previous models for indel evolution assumed that the rates and length distributions of insertions and deletions are equal, here, we propose a richer model that explicitly distinguishes between the two; (2) We introduce numerous summary statistics that allow Approximate Bayesian Computation (ABC) based parameter estimation; (3) We develop a neural-network model-selection scheme to test whether the richer model better fits biological data compared to the simpler model. Our analyses suggest that both our inference scheme and the model-selection procedure achieve high accuracy on simulated data. We further demonstrate that our proposed indel model better fits a large number of empirical datasets and that, for the majority of these datasets, the deletion rate is higher than the insertion rate. Finally, we demonstrate that indel rates are negatively correlated to the effective population size across various phylogenomic clades.
Identification of new marker genes from plant single-cell RNA-seq data using interpretable machine learning methods
Authors: Yan Haidong , Lee Jiyoung , Song Qi , Li Qi , Schiefelbein John , Zhao Bingyu , Li Song
Published: November 2020

An essential step in the analysis of single-cell RNA sequencing data is to classify specific cell types with marker genes. In this study, we have developed a machine learning pipeline called Single cell Predictive markers (SPmarker) to identify novel cell-type marker genes in the Arabidopsis root.

Unlike traditional approaches, our method uses interpretable machine learning methods to select marker genes. We have demonstrated that our method can (1) assign cell types based on cells that were labeled using published methods, (2) project cell types identified by trajectory analysis from one dataset to other datasets, and (3) assign cell types based on internal GFP markers.

Using SPmarker, we have identified hundreds of new marker genes that were not identified before. As compared to known marker genes, we have found more orthologous genes of these new marker genes in corresponding rice single cell clusters. We have also found 172 new marker genes for trichoblast in five non-Arabidopsis species, which expands number of marker genes for this cell type by 35-154%.

Our results represent a new approach to identify cell-type marker genes from scRNA-seq data and pave the way for cross-species mapping of scRNA-seq data in plants.
Language network connectivity increases in prodromal Alzheimer’s disease
Authors: Pistono A. , Senoussi M. , Guerrier L. , Rafiq M. , Gimeno M. , Péran P. , Jucla M. , Pariente J.
Published: November 2020

Language production deficits occur early in the course of Alzheimer’s disease (AD); however, only few studies have focused on language functional networks in prodromal AD. The current study aims to uncover the extent of language alteration at a prodromal stage, on a behavioral, structural and functional level, using univariate and multivariate analyses. Twenty-four AD participants and 24 matched healthy controls underwent a comprehensive language evaluation, a structural T1-3D MRI and resting-state fMRI. We performed seed-based analyses, using the left inferior frontal gyrus and left posterior temporal gyrus as seeds. Then, we analyzed connectivity between executive control networks and language network in each group. Finally, we used multivariate pattern analyses to test whether the two groups could be distinguished based on the pattern of atrophy within the language network; atrophy within the executive control networks, as well as the pattern of functional connectivity within the language network; and functional connectivity within executive control networks. AD participants had language impairment during standardized language tasks and connected-speech production. Univariate analyses were not able to discriminate participants at this stage, while multivariate pattern analyses could significantly predict the group membership of prodromal patients and healthy controls, both when classifying atrophy patterns or connectivity patterns of the language network. Language functional networks could discriminate AD participants better than executive control networks. Most notably, they revealed an increased connectivity at a prodromal stage. Multivariate analyses represent a useful tool for investigating the functional and structural (re-)organization of the neural bases of language.

Highlights

Language network connectivity discriminates prodromal AD from healthy controls

Language network connectivity increases in prodromal AD

Atrophy patterns in the language network do not correlate with connectivity patterns in AD
ER bodies are induced byPseudomonas syringaeand negatively regulate immunity
Authors: Rufián José S. , Elmore James M. , Bejarano Eduardo R. , Beuzon Carmen R. , Coaker Gitta L.
Published: November 2020

ER bodies are endoplasmic reticulum-derived organelles present in plants belonging to theBrassicalesorder. InArabidopsis thaliana, ER bodies are ubiquitous in cotyledons and roots, and present only in certain cell types in rosette leaves. However, both wounding and jasmonic acid treatment induce the formation of ER bodies in leaves. Formation of this structure is dependent on the transcription factorNAI1. The main components of the ER bodies are β-glucosidases (BGLUs), enzymes that hydrolyze specialized compounds. InArabidopsis, PYK10 (BGLU23) and BGLU18 are the most abundant ER body proteins. In this work, we found that ER bodies are downregulated as a consequence of the immune responses induced by bacterial flagellin perception.Arabidopsismutants defective in ER body formation show enhanced responses upon flagellin perception and enhanced resistance to bacterial infections. Furthermore, the bacterial toxin coronatine induces the formation ofde novoER bodies in leaves and its virulence function is partially dependent on this structure. Finally, we show that performance of the polyphagous beet armyworm herbivore,Spodoptera exigua, increases in plants lacking ER bodies. Altogether, we provide new evidence for the role of the ER bodies in plant immune responses.
Uncovering transposable element variants and their potential adaptive impact in urban populations of the malaria vectorAnopheles coluzzii
Authors: Vargas-Chavez Carlos , Longo Pendy Neil Michel , Nsango Sandrine E. , Aguilera Laura , Ayala Diego , González Josefa
Published: November 2020

Abstract

Background

Anopheles coluzziiis one of the primary vectors of human malaria in sub-Saharan Africa. Recently, it has colonized the main cities of Central Africa threatening vector control programs. The adaptation ofAn. coluzziito urban environments is partly due to an increased tolerance to organic pollution and insecticides. While some of the molecular mechanisms for ecological adaptation, including chromosome rearrangements and introgressions, are known, the role of transposable elements (TEs) in the adaptive processes of this species has not been studied yet. To assess the role of TEs in rapid urban adaptation, the first step is to accurately annotate TE insertions in the genomes of natural populations collected in urban settings.

Results

We sequenced using long-reads sixAn. coluzziigenomes from natural breeding sites in two major Central Africa cities. Wede novoannotated the complete set of TEs in these genomes and in an additional high-qualityAn. coluzziigenome available and identified 64 previously undescribed TE families. TEs were non-randomly distributed throughout the genome with significant differences in the number of insertions of several superfamilies across the studied genomes. We identified seven putatively active families with insertions near genes with functions related to vectorial capacity. Moreover, we identified several TE insertions providing promoter and transcription factor binding sites to insecticide resistance and immune-related genes.

Conclusions

The analysis of multiple genomes sequenced using long-read technologies allowed us to generate the most comprehensive TE annotations in this species to date. We identified several TE insertions that could potentially impact both genome architecture and the regulation of functionally relevant genes inAn. coluzzii. These results provide a basis for future studies of the impact of TEs on the biology ofAn. coluzzii.
Inhibition of Biofilm Formation by Modified Oxylipins from the Shipworm SymbiontTeredinibacter turnerae
Authors: Lacerna Noel M. , V. Ramones Cydee Marie , D. Robes Jose Miguel , D. Picart Myra Ruth , O. Tun Jortan , Miller Bailey W. , Haygood Margo G. , Schmidt Eric W. , Salvador-Reyes Lilibeth A. , Concepcion Gisela P.
Published: November 2020

Bioactivity-guided purification of the culture broth of the shipworm endosymbiontTeredinibacter turnerae991H.S.0a.06 yielded a new fatty acid, turneroic acid (1), and two previously described oxylipins (2-3). Turneroic acid (1) is an 18-carbon fatty acid decorated by a hydroxy group and an epoxide ring. Compounds1-3inhibited bacterial biofilm formation inStaphylococcus epidermidis, while only3showed antimicrobial activity against planktonicS. epidermidis. Comparison of the bioactivity of1-3with structurally related compounds indicated the importance of the epoxide moiety for selective and potent biofilm inhibition.

Abstract Figure
Vaccine-induced, but not natural immunity, against the Streptococcal Inhibitor of Complement protects against invasive disease
Authors: Tan Lionel K. K. , Reglinski Mark , Teo Daryl , Reza Nada , Lamb Lucy E. M. , Nageshwaran Vaitehi , Turner Claire E. , Wikstrom Mats , Frick Inga-Maria , Bjorck Lars , Sriskandan Shiranee
Published: November 2020

Highly pathogenicemm1 Streptococcus pyogenesstrains secrete the multidomain Streptococcal inhibitor of complement (SIC) that binds and inactivates components of the innate immune response. We aimed to determine if naturally occurring or vaccine-induced antibodies to SIC are protective against invasiveS. pyogenesinfection. Immunisation with full length SIC protected mice against systemic bacterial dissemination following intranasal or intramuscular infection withemm1 S. pyogenes.Vaccine-induced rabbit anti-SIC antibodies, but not naturally occurring human anti-SIC antibodies, enhanced bacterial clearance in an ex vivo whole blood assay. SIC vaccination of both mice and rabbits resulted in antibody recognition of all domains of SIC, whereas naturally occurring human anti-SIC antibodies recognised the proline-rich region of SIC only. We therefore propose a model whereby natural infection withS. pyogenesgenerates non-protective antibodies against the proline-rich region of SIC, while vaccination with full length SIC permits development of protective antibodies against all SIC domains.
Operation of a TCA cycle subnetwork in the mammalian nucleus
Authors: Kafkia Eleni , Andres-Pons Amparo , Ganter Kerstin , Seiler Markus , Jouhten Paula , Pereira Filipa , Zaugg Judith B , Lancrin Christophe , Beck Martin , Patil Kiran Raosaheb
Published: November 2020

Nucleic acid and histone modifications critically depend on central metabolism for substrates and co-factors. Although a few enzymes related to the formation of these required metabolites have been reported in the nucleus, the corresponding metabolic pathways are considered to function elsewhere in the cell. Here we show that a substantial part of the mitochondrial tricarboxylic acid (TCA) cycle, the biosynthetic hub of epigenetic modification factors, is operational also in the nucleus. Using13C-tracer analysis, we identified activity of glutamine-to-fumarate, citrate-to-succinate, and glutamine-to-aspartate routes in the nuclei ofHeLacells. Proximity labeling mass-spectrometry revealed a spatial vicinity of the involved enzymes with core nuclear proteins, supporting their nuclear location. We further show nuclear localization of aconitase 2 and 2-oxoglutarate dehydrogenase in mouse embryonic stem cells. Together, our results demonstrate operation of an extended metabolic pathway in the nucleus warranting a revision of the canonical view on metabolic compartmentalization and gene expression regulation.
Principles of 3D Compartmentalization of the Human Genome
Authors: Nichols Michael H. , Corces Victor G.
Published: November 2020

Chromatin is organized in the nucleus by CTCF loops and compartmental domains, the latter of which contain sequences bound by proteins capable of mediating interactions among themselves. While compartmental domains are one of the most prominent features of genome 3D organization at the chromosome scale, we lack a nuanced understanding of the different types of compartmental domains present in chromosomes and a mechanistic knowledge of the forces responsible for their formation. In this study, we compared different cell types to identify distinct paradigms of compartmental domain formation in human tissues. We identified and quantified compartmental forces correlated with histone modifications characteristic of transcriptional activity as well as previously underappreciated roles for compartmental domains correlated with the presence of H3K9me3, H3K27me3, or none of these histone modifications. We present a simple computer simulation model capable of predicting compartmental organization based on the biochemical characteristics of independent chromatin features. Using this computational model, we show that the underlying forces responsible for compartmental domain formation in human cells are conserved and that the diverse compartmentalization patterns seen across cells are due to differences in chromatin features. We extend these findings to Drosophila to suggest that the same fundamental forces are at work beyond humans. These results offer mechanistic insights into the fundamental forces driving the 3D organization of the genome.
Mitochondrial respiration contributes to the interferon gamma response in antigen presenting cells
Authors: Kiritsy Michael C. , Mott Daniel , Behar Samuel M. , Sassetti Christopher M. , Olive Andrew J.
Published: November 2020

The immunological synapse allows antigen presenting cells (APC) to convey a wide array of functionally distinct signals to T cells, which ultimately shape the immune response. The relative effect of stimulatory and inhibitory signals is influenced by the activation state of the APC, which is determined by an interplay between signal transduction and metabolic pathways. While toll-like receptor ligation relies on glycolytic metabolism for the proper expression of inflammatory mediators, little is known about the metabolic dependencies of other critical signals such as interferon gamma (IFNγ). Using CRISPR-Cas9, we performed a series of genome-wide knockout screens in macrophages to identify the regulators of IFNγ-inducible T cell stimulatory or inhibitory proteins MHCII, CD40, and PD-L1. Our multi-screen approach enabled us to identify novel pathways that control these functionally distinct markers. Further integration of these screening data implicated complex I of the mitochondrial respiratory chain in the expression of all three markers, and by extension the IFNγ signaling pathway. We report that the IFNγ response requires mitochondrial respiration, and APCs are unable to activate T cells upon genetic or chemical inhibition of complex I. These findings suggest a dichotomous metabolic dependency between IFNγ and toll-like receptor signaling, implicating mitochondrial function as a fulcrum of innate immunity.
Antagonistic modules, SIB1 and LSD1, regulate photosynthesis-associated nuclear genes via GOLDEN2-LIKE transcription factors in Arabidopsis
Authors: Li Mengping , Lee Keun Pyo , Liu Tong , Vivek Dogra , Duan Jianli , Li Mengshuang , Xing Weiman , Kim Chanhong
Published: November 2020

GOLDEN2-LIKE (GLK) transcription factors drive the expression of photosynthesis-associated nuclear genes (PhANGs), indispensable for chloroplast biogenesis. We previously demonstrated that the salicylic acid (SA)-induced SIGMA FACTOR-BINDING PROTEIN 1 (SIB1), a transcription coregulator and positive regulator of cell death, interacts with GLK1 and GLK2 to reinforce their activities. The SIB1-GLK interaction raises the level of light-harvesting antenna proteins in photosystem II, aggravating photoinhibition and singlet oxygen (1O2) burst.1O2then contributes to SA-induced cell death via EXECUTER 1 (EX1,1O2sensor protein)-mediated retrograde signaling upon reaching a critical level. We now reveal that LESION-SIMULATING DISEASE 1 (LSD1), a transcription coregulator and negative regulator of SA-primed cell death, interacts with GLK1/2 to repress their activities. Consistently, the overexpression of LSD1 represses GLK target genes including PhANGs, whereas the loss of LSD1 increases their expression. Remarkably, LSD1 overexpression inhibits chloroplast biogenesis, resembling the characteristicglk1glk2double mutant phenotype. The subsequent chromatin immunoprecipitation analysis coupled with quantitative PCR further reveals that LSD1 inhibits the DNA-binding activity of GLK1 towards its target promoters. The SA-induced nuclear-targeted SIB1 appears to counteractively interact with GLK1/2, leading to the activation of EX1-mediated1O2signaling. Taken together, we provide a working model that SIB1 and LSD1, mutually exclusive SA-signaling components, antagonistically regulate GLK1/2 to fine-tune the expression of PhANGs, thereby modulating1O2homeostasis and related stress responses.
Low prevalence of naturalWolbachiain major malarial vectorsAnopheles culicifaciess.l., andAnopheles stephensi:a first report
Authors: Sankar S. Gowri , Sundari T. Mowna , Anand A. Alwin Prem
Published: November 2020

Wolbachiais an alpha-proteobacteria present in several arthropods. The present study focussed on the identification ofWolbachiainAnopheles culicifaciess.l., andAnopheles stephensi, which are wild malarial vector mosquitoes in India. A total of four hundred and eighty seven adult female mosquito samples were collected using taxonomic keys and confirmed by molecular analysis where 48.25% wasAnopheles culicifaciess.l., and 51.75% wasAnopheles stephensi. The presence ofWolbachiawas identified using16SrRNA,wspandFtsZgenes, where nested PCR of16SrRNA alone was successful and sequenced. Only seven mosquitoes (1.4%) were positive forWolbachia. In silicoand restriction digestion of16SrRNA gene product using RsaI enzyme showed that the identifiedWolbachiabelongs to supergroup B, which is further supported by phylogenetic analysis. Low prevalence rate of naturalWolbachiawas observed inAn. culicifaciess.l. (1.7%) andAn. stephensi(1.2%). This is the first report on the presence ofWolbachiainAnopheles culicifaciess.l. andAnopheles stephensi.
Nuclear Morphology Optimized Deep Hybrid Learning (NUMODRIL): A novel architecture for accurate diagnosis/prognosis of Ovarian Cancer
Authors: Sengupta Duhita , Ali Sk Nishan , Bhattacharya Aditya , Mustafi Joy , Mukhopadhyay Asima , Sengupta Kaushik
Published: November 2020

Nuclear morphological features are potent determining factors for clinical diagnostic approaches adopted by pathologists to analyse the malignant potential of cancer cells. Considering the structural alteration of nucleus in cancer cells, various groups have developed machine learning techniques based on variation in nuclear morphometric information like nuclear shape, size, nucleus-cytoplasm ratio and various non-parametric methods like deep learning have also been tested for analysing immunohistochemistry images of tissue samples for diagnosing various cancers. Our aim is to study the morphometric distribution of nuclear lamin proteins as a specific parameter in ovarian cancer tissues. Besides being the principal mechanical component of the nucleus, lamins also present a platform for binding of proteins and chromatin thereby serving a wide range of nuclear functions like maintenance of genome stability, chromatin regulation. Altered expression of lamins in different subtypes of cancer is now evident from data across the world. It has already been elucidated that in ovarian cancer, extent of alteration in nuclear shape and morphology can determine degree of genetic changes and thus can be utilized to predict the outcome of low to high form of serous carcinoma. In this work, we have performed exhaustive imaging of ovarian cancer versus normal tissue and introduced a novel Deep Hybrid Learning approach on the basis of the distribution of lamin proteins. Although developed with ovarian cancer datasets in view, this architecture would be of immense importance in accurate and fast diagnosis and prognosis of all types of cancer associated with lamin induced morphological changes and would perform across small/medium to large datasets with equal efficiency.

Significance Statement

We have developed a novel Deep Hybrid Learning approach based on nuclear morphology to classify normal and ovarian cancer tissues with highest possible accuracy and speed. Ovarian cancer cells can be easily distinguished from their enlarged nuclear morphology as is evident from lamin A & B distribution pattern. This is the first report to invoke specific nuclear markers like lamin A & B instead of classical haematoxylin-eosin staining in an effort to build parametric datasets. Our approach has been shown to outperform the existing deep learning techniques in training and validation of datasets over a wide range. Therefore this method could be used as a robust model to predict malignant transformations of benign nuclei and thus be implemented in the diagnosis and prognosis of ovarian cancer in future. Most importantly, this method can be perceived as a generalized approach in the diagnosis for all types of cancer.
Diurnal transcript profiling of the diatomSeminavis robustareveals adaptations to a benthic lifestyle
Authors: Bilcke Gust , Osuna-Cruz Cristina Maria , Silva Marta Santana , Poulsen Nicole , D’hondt Sofie , Bulankova Petra , Vyverman Wim , De Veylder Lieven , Vandepoele Klaas
Published: November 2020

1

Coastal regions contribute an estimated 20% of annual gross primary production in the oceans, despite occupying only 0.03% of their surface area. Diatoms frequently dominate coastal sediments, where they experience large variations in light regime resulting from the interplay of diurnal and tidal cycles. Here, we report on an extensive diurnal transcript profiling experiment of the motile benthic diatomSeminavis robusta. Nearly 90% (23,328) of expressed protein-coding genes and 66.9% (1124) of expressed long intergenic non-coding RNAs (lincRNAs) showed significant expression oscillations and are predominantly phasing at night with a periodicity of 24h. Phylostratigraphic analysis found that rhythmic genes are enriched in deeply conserved genes, while diatom-specific genes are predominantly associated with midnight expression. Integration of genetic and physiological cell cycle markers with silica depletion data revealed potential new silica cell wall associated gene families specific to diatoms. Additionally, we observed 1752 genes with a remarkable semidiurnal (12-h) periodicity, while the expansion of putative circadian transcription factors may reflect adaptations to cope with highly unpredictable external conditions. Taken together, our results provide new insights into the adaptations of diatoms to the benthic environment and serve as a valuable resource for diurnal regulation in photosynthetic eukaryotes.
Self-generation and sound intensity interactively modulate perceptual bias, but not perceptual sensitivity
Authors: Paraskevoudi Nadia , SanMiguel Iria
Published: November 2020

The ability to distinguish self-generated stimuli from those caused by external sources is critical for all behaving organisms. Although many studies point to a sensory attenuation of self-generated stimuli, recent evidence suggests that motor actions can result in either attenuated or enhanced perceptual processing depending on the environmental context (i.e., stimulus intensity). The present study employed 2-AFC sound detection and loudness discrimination tasks to test whether sound source (self- or externally-generated) and stimulus intensity (supra- or near-threshold) interactively modulate detection ability and loudness perception. Self-generation did not affect detection and discrimination sensitivity (i.e., detection thresholds and Just Noticeable Difference, respectively). However, in the discrimination task, we observed a significant interaction between self-generation and intensity on perceptual bias (i.e. Point of Subjective Equality). Supra-threshold self-generated sounds were perceived softer than externally-generated ones, while at near-threshold intensities self-generated sounds were perceived louder than externally-generated ones. Our findings provide empirical support to recent theories on how predictions and signal intensity modulate perceptual processing, pointing to interactive effects of intensity and self-generation that seem to be driven by a biased estimate of perceived loudness, rather by changes in detection and discrimination sensitivity.

Highlights

Self-generation and stimulus intensity interactively shape auditory perception.

Supra-threshold self-generated sounds are perceptually attenuated.

When near-threshold, perceived intensity is enhanced for self-generated sounds.

Self-generation and intensity modulate perceptual bias, rather than sensitivity.

Surprise-driven attentional mechanisms may underlie these perceptual shifts.
A meta-analysis of the factors affecting eWOM providing behaviour
Authors: Ismagilova Elvira , Rana Nripendra P. , Slade Emma L. , Dwivedi Yogesh K.
Published: November 2020

Purpose

Numerous studies have examined factors influencing electronic word of mouth (eWOM) providing behaviour. The volume of extant research and inconsistency in some of the findings makes it useful to develop an all-encompassing model synthesising results. Therefore, the purpose of this study is to synthesise findings from existing studies on eWOM by using meta-analysis, which will help to reconcile conflicting findings of factors affecting consumers’ intention to engage in eWOM communications.

Design/methodology/approach

The findings from 51 studies were used for meta-analysis, which was undertaken using comprehensive meta-analysis software.

Findings

Factors affecting eWOM providing behaviour were divided into four groups: personal conditions, social conditions, perceptual conditions and consumption-based conditions. The results of the meta-analysis showed that out of 20 identified relationships, 16 were found to be significant (opinion seeking, information usefulness, trust in web eWOM services, economic incentive, customer satisfaction, loyalty, brand attitude, altruism, affective commitment, normative commitment, opinion leadership, self-enhancement, information influence, tie strength, homophily and community identity).

Research limitations/implications

One of the limitations of this study is that the studies for this research were collected the only form from Web of Science, Scopus and Business Source such as databases, which result in a limited number of studies available for weight and meta-analysis. A wider range of databases should be used by future research. Also, this study only considered quantitative studies and excluded qualitative studies. Thus, future studies could include both types of studies in the meta-analysis.

Practical implications

By focussing on the best predictors of intention to provide eWOM communications (e.g. self-enhancement and trust in web eWOM services) managers can improve reader engagement and information assimilation. Knowing motivations to engage in eWOM helps platform operators design their service in a more customer-oriented way. By better understanding motivations to engage in eWOM communications marketers and researchers can influence individuals’ online information assimilation which can affect consumer purchase decisions, customer loyalty and consumer commitment to the community.

Originality/value

Applying meta-analysis helped the reconciliation of conflicting findings, enabled investigation of the strengths of the relationships between motivations and eWOM providing behaviour and offered a consolidated view. The results of this study facilitate the advancement of current knowledge of information dissemination on the internet, which can influence consumer purchase intention and loyalty.
Social media use and its impact on intrinsic motivation in Generation Z: a case study from Poland
Authors: Król Karol , Zdonek Dariusz
Published: November 2020

Purpose

Activities on social platforms affect the audience. They may impact brand perception, purchasing decisions or motivation to act. Motivation makes people behave in certain ways. The purpose of this paper is to analyse the use of social media and its impact on intrinsic motivation, with a focus on Generation Z users (born between 1994 and 2002).

Design/methodology/approach

The authors conducted multifaceted survey research among full-time and part-time students of one of the largest universities in Poland. The survey was carried out on students of three major fields of study. The analysis involved 427 questionnaires. The data was analysed both with unidimensional and two-dimensional statistical analysis.

Findings

Although the respondents indicated some “motivational aspects” of social media usage, most of them were characterised by a passive attitude and infrequent activity on such websites. Not many of the respondents published actively. The respondents expected valuable content but were not inclined to disseminate it.

Originality/value

Publishing of own content and ability to view others’ content in social media may not be enough to increase the user base of a social platform. One way to do this may be narrowing down or diversification of the array of additional services and functionalities that induce users to increase the use rate.
Hand-arm vibration management: an operational health and safety strategy framework
Authors: Edwards David John , Martek Igor , Ejohwomu Obuks , Aigbavboa Clinton , Hosseini M. Reza
Published: November 2020

Purpose

Human vibration exposure from hand-operated equipment emissions can lead to irreparable and debilitating hand-arm vibration syndrome (HAVS). While work-place health and well-being (H&WB) policies, strategies and procedures have been extensively researched and documented, little has been done to develop a specific strategic framework tailored to the management of hand-arm vibration (HAV). This study fills that gap.

Design/methodology/approach

A mixed philosophical approach of interpretivism and critical realism is adopted within a case study of a utilities contractor. Within this overarching epistemological design, action research approach is implemented via a three-stage investigation, namely, relevant company H&WB documents and procedures were examined, leading to the formulation of semi-structured interview questioning of the H&WB team. Their responses informed the next line of questions, delivered to middle-management responsible for overseeing H&S.

Findings

The findings are instructive in revealing that while substantial documentation management (augmented with protocols and checks) was in place, the system fell short of implementation within the workforce and thus failed to preserve worker H&WB. The investigation generated recommendations for shoring up H&WB deficiencies observed and developed a theoretical model to represent these. Though these recommendations were developed in response to a specific case, they form the core of a HAV operational H&WB strategy framework with applicability over a broader context.

Originality/value

This research provides unique insight into contemporary industry practices employed to manage HAV in the workplace and represents an invaluable opportunity to learn from prevailing practices and rectify deficiencies observed.
Current scenario of wind power in India, government policies, initiatives, status and challenges
Authors: Satpute Anand Vijay , Kumar E. Vijay
Published: November 2020

Purpose

This paper aims to review the role of government initiatives for the development of wind power industries in India, to provide better and benevolent policies in the production of wind energy density and to maximize the use of the renewable source of energy which permits to reduce carbon emission from the coal-based power plant and to curtail tackle need of society and mitigate poverty.

Design/methodology/approach

The present study is carried out on the current position of wind power generation in India. Government policies for promoting clean energy and associated problems are also analysed herein detail. However, secondary approaches are opted in terms of alertness of caring for the environment hazardous and reduced the major economies aspects by fulfilling the schema of Kyoto Protocol and Paris Agreement, United Nations Framework Convention on Climate Change.

Findings

The prospective of wind energy generation is huge, as an ancient source of energy, wind can be used both as a source of electricity and for agricultural, irrigation uses. The study of wind turbine blades and its features showed how it can be properly fabricated and used to extract the maximum power, even at variable and low wind speeds.

Research limitations/implications

Although India has achieved a remarkable advancement in wind power sectors, it needs to eradicate all the loopholes to evolve as super power in wind energy sector leaving behind its rivalry China. To do this, it is required to develop in many fields such as skilled manpower, advancement in research and development, grid and turbine installation, proper distribution, smooth land acquisition, modern infrastructure, high investment and above all industry friendly government policy.

Practical implications

The present study finds out effects of wind power energy as a source of renewable energy to mitigate energy crisis.

Social implications

As a source of renewable energy and cost effectiveness, wind power can be evolved as a potential means enhance social life.

Originality/value

The present paper caries out critical analysis for the active use of renewable energy in the present and forthcoming days. Such unique analysis must help India as a developing nation to balance its energy crisis.
Basic psychological needs satisfaction and student engagement: the importance of novelty satisfaction
Authors: Benlahcene Abderrahim , Kaur Amrita , Awang-Hashim Rosna
Published: November 2020

Purpose

The purpose of this paper is to examine the associations between students' basic psychological needs satisfaction, including novelty satisfaction, and the four aspects of student engagement.

Design/methodology/approach

Data were collected from a total sample of 743 undergraduate students from three public universities in northern Malaysia. Structural equation modelling (SEM) was used to analyse the data.

Findings

Competence and relatedness were positively related to the four aspects of student engagement, while autonomy satisfaction was found to relate to agentic engagement. Novelty satisfaction, on the other hand, is related positively with behavioural, emotional and cognitive engagement.

Research limitations/implications

The results provide a new understanding on the importance of novelty satisfaction alongside existing needs in self-determination theory (SDT) in enhancing student engagement.

Practical implications

Educators are encouraged to develop strategies to provide novelty support and facilitate students' basic needs satisfaction in order to establish a motivational learning environment that vitalises students' engagement.

Originality/value

This study breaks new ground by testing the unique relationships of novelty satisfaction along with the psychological needs for autonomy, competence and relatedness, with the four aspects of student engagement in higher education.
How bracing and heating regimes influence the fire performance of composite frames
Authors: Bahr Oliver
Published: November 2020

Purpose

Unbraced one-bay composite frames are an interesting load-bearing structure for buildings with up to three storeys. However, their fire design is demanding given the lack of simplified design methods. This paper aims to deepen the understanding of the load-bearing behaviour of both unbraced and braced frames when exposed to fire.

Design/methodology/approach

In a previous paper, a numerical model for the fire design of these frames was established and validated with good agreement against fire tests. In the current paper, this model was used to compare the typical differences between braced, semi-braced and unbraced composite frames under fire conditions. Further studies addressed the effect of different heating regimes, i.e. partial fire exposure of the columns in the frames and varying location of the ISO standard fire.

Findings

Numerical investigations showed that it is necessary to take local failure and deformation limits of the fire-exposed frames into account. On this basis, unbraced composite frames can compete with braced frames as they have to endure less thermal restraints than braced frames.

Originality/value

In contrast to other investigations on frames, the numerical model is able to take into account the shear failure, which is especially important within the frame corners. Using this model, it is shown that limited sway is reasonable to reduce thermal restraints and hence local stresses. In this regard, the concept of semi-rigid composite joints with a distinct amount of reinforcement has proven to be very rational in fire design.
Sustainable procurement initiatives and their risk-related costs: a framework and a case study application
Authors: Hald Kim Sundtoft , Wiik Sofia , Larssen Anton
Published: November 2020

Purpose

The purpose of this paper is to contribute to a better understanding of the economic consequences of aiming for sustainable procurement. The authors develop and apply a framework designed to identify and measure the risk-related cost trade-offs inherent in initiatives designed to improve sustainability in procurement.

Design/methodology/approach

The research uses a combined conceptual and case-based research method. A model is developed from theory; subsequently, it is applied using an action research approach and its limitations in use are identified.

Findings

Specifically, the authors develop and exemplify a framework designed to measure the risk-related cost impact of initiatives to improve sustainability in procurement and develop an initial list of difficulties and constraints when in use.

Research limitations/implications

This research presents one instance of a model that is applied in one single setting. The purpose is not to generalize, but to provide a deeper understanding of the interconnectedness between sustainability initiatives, risk mitigation and their economic effect. The framework and its calculation methods have to be further developed and refined using more case studies.

Practical implications

The model can provide initial inspiration and a starting point for firms with the ambition to develop business case models to assess initiatives to improve sustainability in procurement. Its main strength is to demonstrate the multiple cause–effect relationships as well as trade-offs involved in accounting for the risk related effect of a sustainable procurement initiative.

Originality/value

The presented research contributes to the existing literature by conceptually developing a framework with the potential of outlining the risk-related cost implications of investments initiatives designed to improve sustainability in procurement.
Effect of crosslinking agents on the strength characteristics of cellulosic fabrics using 23 32 mixed level factorial
Authors: Naeem Farhana , Asim Fareha , Tufail Muhammad
Published: November 2020

Purpose

Low pilling and wrinkle-free appearance of cellulosic fabrics are always demanded. Resin finishes are applied to improve these properties, but there is an adverse effect of the resin finish as it tends to reduce the strength of the fabrics. Therefore, the effect of the two most important finishes; anti-pilling and resin finish, on the strength characteristics of 100% viscose and 50:50 Viscose/cotton plain and satin fabrics were investigated in this paper. The purpose of this study is to identify significant factors affecting the strength of fabrics finished with crosslinking agents [non-ionic acrylate copolymer and (dimethyloldihydroxyethyleneurea)].

Design/methodology/approach

A statistical model of 23 32 mixed level factorial design was used for the study. Appratan N9211 (A) and Arkofix NF (B) were tested at three concentrations, whereas three factors fabric; weave (C), blend ratio (D) and curing method (E) were tested at two levels. The performance of the finish was evaluated by two response variables, which were tensile and tear strength.

Findings

The various conditions of high strength values of the fabrics were presented in this paper. It was found that the tear strength of the fabrics increased after finishing except for 50:50 viscose/cotton plain fabric, whereas the tensile strength of plain fabrics is better at shock cure and for a satin normal cure is better. The model adequacy plots exhibit that the assumptions of normality and independence are not desecrated. Moreover, the values of “predicted R2” are in reasonable agreement with the “adjusted R2,” which confirms that models have been accounted for most of the inconsistency.

Originality/value

This paper is a part of my PhD dissertation. Unlike the previous studies, this paper investigated the effect of two crosslinking agents, Appretan N9211 as anti-pilling and Arkofix NF as wrinkle resistant agents on 100% viscose and 50:50 viscose/cotton plain and satin. Three different concentrations of both the crosslinking agents were used. Also, fixation of the finishes was carried out at a normal cure and shock cure.
Polyaniline dispersed by Kevlar fiber for uptake of organic dye
Authors: Liu Yi , Wu Fanhua , Tian Xinwei , Hu Xiaoyang , Liu Yongfeng , Zhao Xiandong , Qu Rongjun , Ji Chunnuan , Niu Yuzhong
Published: November 2020

Purpose

This paper aims to focus on the preparation of Kevlar fiber (KF) and alkaline hydrolyzed KF (KF-H) to improve the dispersed condition of polyaniline (PAn), as the aggregation of PAn would lead to some adsorption sites buried. And then the materials were used to enrich anionic dye Congo red (CR) from aqueous solution.

Design/methodology/approach

The materials (KF@PAn and KF-H@PAn) were designed by means of “diffusion-interfacial-polymerization” under mild condition as high affinity due to the structural properties of PAn, KF and KF-H. The dispersed degree of PAn on the surface of KF and KF-H was validated according to adsorption efficiency for CR.

Findings

The content of PAn introduced was not beyond 20 wt.%, while adsorption capacity for CR was significantly enhanced by 4–8 times (on the basis of kinetic data) according to the calculation only by the content of PAn due to KF and alkaline hydrolyzed KF exhibited almost no adsorption for CR, indicating dispersed situation of PAn coating was greatly enhanced and more active sites exposed, which was favorable for the adsorption process. Presence of NaCl would exhibit a more or less positive effect on CR uptake, suggesting the materials could be used for high salt environment.

Research limitations/implications

The investigated means of dispersed degree of PAn on the surface of KF and KF-H are the further and future investigation.

Practical implications

This study will provide a method to improve the dispersed situation of PAn and a theoretical support to treat anionic dyes from aqueous solution especially for salt environment.

Originality/value

The results showed that the dispersed condition of PAn on the surface of KF and KF-H was greatly improved. According to the adsorption capacities for CR, it can be concluded that part of adsorption sites were buried due to the aggregation of PAn, and introduction of KF and KF-H, buried adsorption sites decreased greatly. This study will provide a method to decrease buried adsorption sites of PAn and a contribution for their convenient application in wastewater treatment especially for high salt environment.