bluuebunny/crossref_metadata_2025 huggingface dataset:
Immunological factors, but not clinical features, predict visceral leishmaniasis relapse in patients co-infected with HIV
Authors: Takele Yegnasew , Mulaw Tadele , Adem Emebet , Shaw Caroline Jayne , Franssen Susanne Ursula , Womersley Rebecca , Kaforou Myrsini , Taylor Graham Philip , Levin Michael , Müller Ingrid , Cotton James Anthony , Kropf Pascale
Published: March 2021

Visceral leishmaniasis (VL) has emerged as a clinically important opportunistic infection in HIV patients, as VL/HIV co-infected patients suffer from frequent VL relapse. Here, we followed cohorts of VL patients with or without HIV co-infections in Ethiopia and collected detailed clinical and immunological data during 12 months of follow-up. By the end of the study 78.1% of VL/HIV patients, but none of the VL only patients, had relapsed. Despite clinically defined cure, VL/HIV patients maintained high parasite loads, low BMI, hepatosplenomegaly and pancytopenia throughout follow-up. During detailed immunological study throughout the follow-up period, we identified three markers associated with VL relapse: i) failure to restore antigen-specific production of IFNγ, ii) persistently low CD4+T cell counts, and iii) high expression of PD1 on CD4+T cells. We show that these three markers combine well in predicting VL relapse, and that all three measurements are needed for optimal predictive power. These three immunological markers can be measured in primary hospital settings in Ethiopia and can predict VL relapse after anti-leishmanial therapy. The use of our prediction model has the potential to improve disease management and patient care.
Acitretin mitigates uroporphyrin-induced bone defects in congenital erythropoietic porphyria models
Authors: Cunha Juliana Bragazzi , Elenbaas Jared S , Maitra Dhiman , Kuo Ning , Azuero-Dajud Rodrigo , Ferguson Allison C , Griffin Megan S , Lentz Stephen I , Shavit Jordan A , Omary M Bishr
Published: March 2021

Congenital erythropoietic porphyria (CEP) is a rare genetic disorder leading to accumulation of uro/coproporphyrin-I in tissues due to inhibition of uroporphyrinogen-III synthase. Clinical manifestations of CEP include bone fragility, severe photosensitivity and photomutilation. Currently there is no specific treatment for CEP, except bone marrow transplantation, and there is an unmet need for treating this orphan disease. Fluorescent porphyrins cause protein aggregation, which led us to hypothesize that uroporphyrin-I accumulation leads to protein aggregation and CEP-related bone phenotype. We developed a zebrafish model that phenocopies features of CEP. As in human patients, uroporphyrin-I accumulated in the bones of zebrafish, leading to impaired bone development. Furthermore, in an osteoblast-like cell line, uroporphyrin-I decreased mineralization, aggregated bone matrix proteins, activated endoplasmic reticulum stress and disrupted autophagy. Using high-throughput drug screening, we identified acitretin, a second-generation retinoid, and showed that it reduced uroporphyrin-I accumulation and its deleterious effects on bones. Our findings provide a new CEP experimental model and a potential repurposed therapeutic.
Evolution of the insect PPK gene family
Authors: Latorre-Estivalis Jose Manuel , Almeida Francisca Cunha , Pontes Gina , Dopazo Hernán , Barrozo Romina , Lorenzo Marcelo Gustavo
Published: March 2021

InsectPickpocket(PPK) receptors mediate the detection of stimuli of diverse sensory modalities, therefore having a relevant role for environmental sounding. Notwithstanding their relevance, studies on their evolution are scarce. We have analyzed the genomes of 26 species belonging to 8 insect orders (Blattodea, Orthoptera, Hemiptera, Phthiraptera, Hymenoptera, Lepidoptera, Coleoptera, and Diptera) to identify their PPK repertoires and study the evolution of this gene family. PPKs were detected in all genomes analyzed, with a total of 578 genes identified that distributed in 7 subfamilies. Our phylogenetic analysis allowed clarifying that theppk17gene appears to be the most divergent family member, composing a new group designed as subfamily VII. According to our analysis, PPKs evolved under a birth-and-death model that generated lineage-specific expansions usually located in clusters and the effect of strong purifying selection was seen for several orthogroups. Subfamily V was the largest one, presenting half of all PPKs studied, including a mosquito-specific expansion that can be considered a new target for pest control. Consistently with their sensory role, PPKs present a high gene turnover that generated considerable variation in the size of insect repertoires:Musca domestica(59),Blattella germanica(41),Culex quinquefasciatus(48), andAedes albopictus(51) presented the largest PPK repertoires, whilePediculus humanus(onlyppk17), bees and ants (6-9) had the smallest ones. The expansions identified inM. domesticaandBl. germanicaalso show promise as specific targets for controlling these nuisance insects. Our phylogenetic analysis revealed a subset of prevalent PPKs across insect genomes, suggesting a very conserved function that resembles the case ofantennalionotropic receptors. Finally, we identified new highly conserved residues in the second transmembrane domain that may be key for receptor function. Besides, more than a hundred PPK sequences presented calmodulin binding motifs, suggesting that at least some members of this family may amplify sensory responses as previously proposed forD. melanogaster ppk25. Overall, our study is a first attempt to characterize the evolutionary history of this family of sensory receptors, revealing relevant unknown features and clade-specific expansions.
A stochastic model of hippocampal synaptic plasticity with geometrical readout of enzyme dynamics
Authors: Rodrigues Yuri Elias , Tigaret Cezar , Marie Hélène , O’Donnell Cian , Veltz Romain
Published: March 2021

Discovering the rules of synaptic plasticity is an important step for understanding brain learning. Existing plasticity models are either 1) top-down and interpretable, but not flexible enough to account for experimental data, or 2) bottom-up and biologically realistic, but too intricate to interpret and hard to fit to data. To avoid the shortcomings of these approaches, we present a new plasticity rule based on a geometrical readout mechanism that flexibly maps synaptic enzyme dynamics to predict plasticity outcomes. We apply this readout to a multi-timescale model of hippocampal synaptic plasticity induction that includes electrical dynamics, calcium, CaMKII and calcineurin, and accurate representation of intrinsic noise sources. Using a single set of model parameters, we demonstrate the robustness of this plasticity rule by reproducing nine publishedex vivoexperiments covering various spike-timing and frequency-dependent plasticity induction protocols, animal ages, and experimental conditions. Our model also predicts thatin vivo-like spike timing irregularity strongly shapes plasticity outcome. This geometrical readout modelling approach can be readily applied to other excitatory or inhibitory synapses to discover their synaptic plasticity rules.
Can good broiler flock welfare prevent colonization byCampylobacter?
Authors: Rawson Thomas , Colles Frances M. , Smith Adrian L. , Dawkins Marian Stamp , Bonsall Michael B.
Published: March 2021

Using data on rearing and welfare metrics of multiple commercial broiler flocks from the last ten years, we investigate how welfare measures such as hock burn, mortality, weight, and pododermatitis, among others, impact the likelihood of a flock becoming colonized byCampylobacter. Using both logistic regression and Bayesian networks, we show that, while some welfare metrics were weakly related toCampylobactercolonization, evidence could not be found to suggest that these metrics actively exacerbatedCampylobactercolonization, rather that they were both symptoms of the same underlying cause. Instead, observed dependency on the management of the flock suggested that yet-undiscovered differences in rearing practise were the principal cause of both poor bird welfare and increased risk ofCampylobacter, suggesting that action can be taken to improve both these factors simultaneously.
Plant Metabolic Network: A multi-species resource of plant metabolic information
Authors: Hawkins Charles , Ginzburg Daniel , Zhao Kangmei , Dwyer William , Xue Bo , Xu Angela , Rice Selena , Cole Benjamin , Paley Suzanne , Karp Peter , Rhee Seung Yon
Published: March 2021

Plant metabolism is a pillar of our ecosystem, food security, and economy. To understand and engineer plant metabolism, we first need a comprehensive and accurate annotation of all metabolic information across plant species. As a step towards this goal, we previously created the Plant Metabolic Network (PMN), an online resource of curated and computationally predicted information about the enzymes, compounds, reactions, and pathways that make up plant metabolism. Here we report PMN 15, which contains genome-scale metabolic pathway databases of 126 algal and plant genomes, ranging from model organisms to crops to medicinal plants, and new tools for analyzing and viewing metabolism information across species and integrating omics data in a metabolic context. We systematically evaluated the quality of the databases, which revealed that our semi-automated validation pipeline dramatically improves the quality. We then compared the metabolic content across the 126 organisms using multiple correspondence analysis and found that Brassicaceae, Poaceae, and Chlorophyta appeared as metabolically distinct groups. To demonstrate the utility of this resource, we used recently published sorghum transcriptomics data to discover previously unreported trends of metabolism underlying drought tolerance. We also used single-cell transcriptomics data from theArabidopsisroot to infer cell-type specific metabolic pathways. This work shows the continued growth and refinement of the PMN resource and demonstrates its wide-ranging utility in integrating metabolism with other areas of plant biology.

One-sentence Summary

The Plant Metabolic Network is a collection of databases containing experimentally-supported and predicted information about plant metabolism spanning many species.
Arrayed multicycle drug screens identify broadly acting chemical inhibitors for repurposing against SARS-CoV-2
Authors: Murer Luca , Volle Romain , Andriasyan Vardan , Meili Nicole , Yang Liliane , Sequeira Daniela , Gomez-Gonzalez Afonso , Petkidis Anthony , Olszewski Dominik , Bauer Michael , Suomalainen Maarit , Kuttler Fabien , Turcatti Gerardo , Greber Urs F.
Published: March 2021

Coronaviruses (CoVs) circulate in humans and animals, and expand their host range by zoonotic and anthroponotic transmissions. Endemic human CoVs, such as 229E and OC43 cause limited respiratory disease, and elicit short term anti-viral immunity favoring recurrent infections. Yet, severe acute respir-atory syndrome (SARS)-CoV-2 spreads across the globe with unprecedented impact on societies and economics. The world lacks broadly effective and affordable anti-viral agents to fight the pandemic and reduce the death toll. Here, we developed an image-based multicycle replication assay for focus for-mation of α-coronavirus hCoV-229E-eGFP infected cells for screening with a chemical library of 5440 compounds arrayed in 384 well format. The library contained about 39% clinically used compounds, 26% in phase I, II or III clinical trials, and 34% in preclinical development. Hits were counter-selected against toxicity, and challenged with hCoV-OC43 and SARS-CoV-2 in tissue culture and human bronchial and nasal epithelial explant cultures from healthy donors. Fifty three compounds inhibited hCoV-229E-GFP, 39 of which at 50% effective concentrations (EC50) < 2μM, and were at least 2-fold separated from toxicity. Thirty nine of the 53 compounds inhibited the replication of hCoV-OC43, while SARS-CoV-2 was inhibited by 11 compounds in at least two of four tested cell lines. Six of the 11 compounds are FDA-approved, one of which is used in mouth wash formulations, and five are systemic and orally available. Here, we demonstrate that methylene blue (MB) and mycophenolic acid (MPA), two broadly available low cost compounds, strongly inhibited shedding of infectious SARS-CoV-2 at the apical side of the cultures, in either pre- or post-exposure regimens, with somewhat weaker effects on viral RNA release indicated by RT-qPCR measurements. Our study illustrates the power of full cycle screens in repurposing clinical compounds against SARS-CoV-2. Importantly, both MB and MPA reportedly act as immunosuppressants, making them interesting candidates to counteract the cytokine storms affecting COVID-19 patients.
The long non-coding RNAMaTAR20promotes mammary tumor growth by regulating angiogenesis pathways
Authors: Diermeier Sarah D. , Chang Kung-Chi , Frewen Ashleigh , Taaffe Padraig , Grans Joke C. , Xiong Haoyu , Benz Brian A. , Russo Suzanne , Nowak Dawid , Hearn Stephen , Yu Allen , Wilkinson John E. , Rigo Frank , Spector David L.
Published: March 2021

Long non-coding RNAs (lncRNAs) are an emerging class of regulatory molecules that have been shown to play important roles in tumorigenesis and cancer progression. Here, we studied the recently identified lncRNAMammary Tumor Associated RNA 20(MaTAR20) in mammary cancer progression. A CRISPR/Cas9 knockout ofMaTAR20in the metastatic 4T1 cell line led to reduced cancer cell proliferation and increased cell surface adhesion compared to control cells. Consistent with these knockout results antisense oligonucleotide (ASO) mediated knockdown ofMaTAR20resulted in reduced growth and invasion in 4T1 cells, and in primary mammary tumor organoids derived from the MMTV-PyMT mouse model of breast cancer. Injection ofMaTAR20-specific ASOs subcutaneously into tumor bearing MMTV-PyMT mice resulted in smaller and highly necrotic tumors in comparison to mice injected with a scrambled control ASO. To investigate the molecular mechanism by whichMaTAR20acts to advance mammary tumor progression, we applied a combination of RNA-sequencing and RNA-pulldown coupled to DNA-sequencing. These analyses demonstrated that the nuclear retained lncRNA is associated with several essential cancer signaling pathways such as VEGF signaling. In particular,MaTAR20directly binds to and regulates the expression ofTnfsf15. Our results indicate thatMaTAR20is an important driver of mammary tumor progression and represents a promising new therapeutic target.
Novel insights in the pathophysiology of α-synuclein dysregulation on D2 receptor activity contributing to the vulnerability of dopamine neurons
Authors: Dagra Abeer , Miller Douglas R. , Shaerzadeh Fatemeh , Lin Min , Gopinath Adithya , Harris Sharonda , Sorrentino Zachary A. , Velasco Sophia , Alonge Adetola R , Azar Janelle , Lebowitz Joe J , Ulm Brittany , Bu Anthea-Mengfei , Hansen Carissa A. , Urs Nikhil , Giasson Benoit I. , Khoshbouei Habibeh
Published: March 2021

Pathophysiological damages and loss of function of dopamine neurons precedes their demise and contributes to the early phases of Parkinson’s disease. The presence of aberrant intercellular pathological inclusions of the protein α-synuclein within ventral midbrain dopaminergic neurons is one of the cardinal features of Parkinson’s disease. We employed multiple complementary approaches in molecular biology, electrophysiology, and live-cell imaging to investigate how excessive α-synuclein levels alters multiple characteristics of dopaminergic neuronal dynamics and dopamine transmission prior to neuronal demise. These studies demonstrate that α-synuclein dysregulation of D2 receptor autoinhibition contributes to the vulnerability of dopaminergic neurons, and that modulation thereof can ameliorate the resulting pathophysiology. These novel findings provide mechanistic insights in the insidious loss of dopaminergic function and neurons that characterize Parkinson’s disease progression with significant therapeutic implications.
Dopamine facilitates fear memory formation in the human amygdala
Authors: Frick Andreas , Björkstrand Johannes , Lubberink Mark , Eriksson Allison , Fredrikson Mats , Åhs Fredrik
Published: March 2021

Learning which environmental cues that predict danger is crucial for survival and accomplished through Pavlovian fear conditioning. In humans and rodents alike, fear conditioning is amygdala-dependent and rests on similar neurocircuitry. Rodent studies have implicated a causative role for dopamine in the amygdala during fear memory formation, but the role of dopamine in aversive learning in humans is unclear. Here, we show dopamine release in the amygdala and striatum during fear learning in humans. Using simultaneous positron emission tomography and functional magnetic resonance imaging, we demonstrate that the amount of dopamine release is linked to strength of conditioned fear responses and linearly coupled to learning-induced memory trace activity in the amygdala. Thus, like in rodents, formation of amygdala-dependent fear memories in humans seems to be facilitated by endogenous dopamine release, supporting an evolutionary conserved neurochemical mechanism for aversive memory formation.
Estimating smooth and sparse neural receptive fields with a flexible spline basis
Authors: Huang Ziwei , Ran Yanli , Euler Thomas , Berens Philipp
Published: March 2021

Spatio-temporal receptive field (STRF) models are frequently used to approximate the computation implemented by a sensory neuron. Typically, such STRFs are assumed to be smooth and sparse. Current state-of-the-art approaches for estimating STRFs based empirical Bayes estimation encode such prior knowledge into a prior covariance matrix, whose hyperparameters are learned from the data, and thus provide STRF estimates with the desired properties even with little or noisy data. However, empirical Bayes methods are often not computationally efficient in high-dimensional settings, as encountered in sensory neuroscience. Here we pursued an alternative approach and encode prior knowledge for estimation of STRFs by choosing a set of basis function with the desired properties: a natural cubic spline basis. Our method is computationally efficient, and can be easily applied to Linear-Gaussian and Linear-Nonlinear-Poisson models as well as more complicated Linear-Nonlinear-Linear-Nonlinear cascade model or spike-triggered clustering methods. We compared the performance of spline-based methods to no-spline ones on simulated and experimental data, showing that spline-based methods consistently outperformed the no-spline versions. We provide a Python toolbox for all suggested methods (https://github.com/berenslab/RFEst/).
Perceptual and Semantic Representations at Encoding Contribute to True and False Recognition of Objects
Authors: Naspi Loris , Hoffman Paul , Devereux Barry , Morcom Alexa
Published: March 2021

When encoding new episodic memories, visual and semantic processing are proposed to make distinct contributions to accurate memory and memory distortions. Here, we used functional magnetic resonance imaging (fMRI) and representational similarity analysis to uncover the representations that predict true and false recognition of unfamiliar objects. Two semantic models captured coarse-grained taxonomic categories and specific object features, respectively, while two perceptual models embodied low-level visual properties. Twenty-eight female and male participants encoded images of objects during fMRI scanning, and later had to discriminate studied objects from similar lures and novel objects in a recognition memory test. Both perceptual and semantic models predicted true memory. When studied objects were later identified correctly, neural patterns corresponded to low-level visual representations of these object images in the early visual cortex, lingual, and fusiform gyri. In a similar fashion, alignment of neural patterns with fine-grained semantic feature representations in the fusiform gyrus also predicted true recognition. However, emphasis on coarser taxonomic representations predicted forgetting more anteriorly in ventral anterior temporal lobe, left perirhinal cortex, and left inferior frontal gyrus. In contrast, false recognition of similar lure objects was associated with weaker visual analysis posteriorly in early visual and left occipitotemporal cortex. The results implicate multiple perceptual and semantic representations in successful memory encoding and suggest that fine-grained semantic as well as visual analysis contributes to accurate later recognition, while processing visual image detail is critical for avoiding false recognition errors.

Significance Statement

People are able to store detailed memories of many similar objects. We offer new insights into the encoding of these specific memories by combining fMRI with explicit models of how image properties and object knowledge are represented in the brain. When people processed fine-grained visual properties in occipital and inferior temporal cortex, they were more likely to be recognize the objects later, and less likely to falsely recognize similar objects. In contrast, while object-specific feature representations in fusiform predicted accurate memory, coarse-grained categorical representations in frontal and temporal regions predicted forgetting. The data provide the first direct tests of theoretical assumptions about encoding true and false memories, suggesting that semantic representations contribute to specific memories as well as errors.
An ammonium transporter is a non-canonical olfactory receptor for ammonia
Authors: Vulpe Alina , Kim Hyong S. , Ballou Sydney , Wu Shiuan-Tze , Grabe Veit , Gonzales Cesar Nava , Sachse Silke , Jeanne James M , Su Chih-Ying , Menuz Karen
Published: March 2021

Two families of ligand-gated ion channels function as olfactory receptors in insects. Here, we show that these canonical olfactory receptors are not necessary for responses to ammonia, a key ecological odor that is attractive to many insects including disease vectors and agricultural pests. Instead, we show that a member of the ancient electrogenic ammonium transporter family, Amt, is a new type of olfactory receptor. We report two hitherto unidentified olfactory neuron populations that mediate neuronal and behavioral responses to ammonia. Their endogenous ammonia responses are Amt-dependent, and ectopic expression of eitherDrosophilaorAnophelesAmt confers ammonia sensitivity. Amt is the first transporter known to function as an olfactory receptor in animals, and its role may be conserved across insect species.
NeuriteNet: A Convolutional Neural Network for determining morphological differences in neurite growth
Authors: Vecchi Joseph , Mullan Sean , Lopez Josue , Hansen Marlan R. , Sonka Milan , Lee Amy
Published: March 2021

Background

During development or regeneration, neurons extend processes (i.e., neurites) via mechanisms that can be readily analyzed in culture. However, defining the impact of a drug or genetic manipulation on such mechanisms can be challenging due to the complex arborization and heterogeneous patterns of neurite growthin vitro.

New Method

NeuriteNet is a Convolutional Neural Network (CNN) sorting model that uses a novel adaptation of the XRAI saliency map overlay, which is a region-based attribution method. NeuriteNet compares neuronal populations based on differences in neurite growth patterns, sorts them into respective groups, and overlays a saliency map indicating which areas differentiated the image for the sorting procedure.

Results

In this study, we demonstrate that NeuriteNet effectively sorts images corresponding to dissociated neurons into control and treatment groups according to known morphological differences. Furthermore, the saliency map overlay highlights the distinguishing features of the neuron when sorting the images into treatment groups. NeuriteNet also identifies novel morphological differences in neurites of neurons cultured from control and genetically modified mouse strains.

Comparison with Existing Methods

Unlike other neurite analysis platforms, NeuriteNet does not require manual manipulations, such as segmentation of neurites prior to analysis, and is more accurate than experienced researchers for categorizing neurons according to their pattern of neurite growth.

Conclusions

NeuriteNet can be used to effectively screen for morphological differences in a heterogeneous group of neurons and to provide feedback on the key features distinguishing those groups via the saliency map overlay.

Highlights

NeuriteNet is a machine learning model developed to identify differences in control and experimental groups of cultured neurons based on morphological criteria.

NeuriteNet’s saliency map highlights the features of the image that associate the neuron with a particular group.

NeuriteNet outperforms trained researchers in assigning neurons to control or experimental groups with a known morphological difference as well as those with no previously described difference.
DiaThor: R package for computing diatom metrics and biotic indices
Authors: Nicolosi Gelis M.M. , Sathicq M.B. , Jupke J. , Cochero J.
Published: March 2021

Diatoms are widely used to detect changes in water quality due to their specific sensibility to a variety of environmental conditions. Among the different diatom-based tools to measure water quality, the biotic indices, ecological and morphological traits are the most commonly used.

DiaThor, contains 18 functions that provide morphological data of the samples (number and shape of chloroplasts, total biovolume), ecological data (species richness, evenness, diversity, size classes, ecological guilds, ecological preferences) and biotic indices (Descy Index, EPID Index, Indice Diatomique Artois-Picardie, Swiss Diatom Index, Pampean Diatom Index, ILM index, Specific Pollution sensitivity Index, Lobo Index, Sládecek index, SPEARherbicidesindex and the Trophic index). A web application (in Shiny) was also developed to provide access to the package for those users not familiar with the R environment.

The structure of the package, how it functions and the structure of the input and output data are explained. To demonstrate the most common use ofDiaThor, an example of the package performance is also provided.

TheDiaThorpackage aims to contribute to the water quality assessment based on diatom assemblages, while also providing researchers with an open platform to suggest new statistics and functionalities to be integrated into future builds.
A holistic model for Global Industry 4.0 readiness assessment
Authors: Tripathi Shubham , Gupta Manish
Published: March 2021

Purpose

Transformation to Industry 4.0 has become crucial for nations, and a coherent transformation strategy requires a comprehensive picture of current status and future vision. This study presents a comprehensive model for readiness assessment of nations based on rigorous analysis of several global indices and academic Industry 4.0 literature.

Design/methodology/approach

A holistic approach is taken considering overall socioeconomic development along with industrial innovation and seven readiness dimensions: enabling environment, human resource, infrastructure, ecological sustainability, innovation capability, cybersecurity and consumers. The indicators used for evaluation are standard metrics for which data are collected from reputed sources such as World Bank, United Nations Educational Scientific and Cultural Organization (UNESCO), World Economic Forum (WEF) and International Organization for Standardization (ISO), and hence internationally acceptable.

Findings

The formulated model is used to evaluate Industry 4.0 readiness of 126 economies that account for 98.25% of world’s gross national income. Observations show poor scores of most economies on innovation capability and cybersecurity dimension as compared to other 5 dimensions. In 75% countries, I4.0 readiness score is below 0.5 on a scale of 0–1(completely ready), highest being 0.65 for Denmark.

Originality/value

A systematic literature review revealed lack of assessment models discussing a nation's current status or readiness for Industry 4.0. This academic study is first of its kind.
Automatic recognition and 3D modeling of the neck-shoulder human shape based on 2D images
Authors: Wang Ting , Gu Bingfei
Published: March 2021

Purpose

This study focused on how to realize automatic recognition of young women's neck-shoulder shape based on the front and side images.

Design/methodology/approach

The reverse engineering software was used to measure the body sizes of the neck-shoulder part based on the young women's three-dimensional (3D) point cloud data, and the important parameters closely related to the neck-shoulder shape were determined. The neck-shoulder shape of the subjects was classified to establish the classification rules. Then, based on the front and side images, the human body contour was extracted by Matlab, and the data required for neck-shoulder shape classification were obtained by identifying the feature points.

Findings

Through the cluster analysis based on the shoulder angle, back angle, shoulder depth/width ratio and armpit depth/width ratio, young women's neck-shoulder shape was divided into four categories, namely round wide shoulder, flat narrow shoulder, round drop shoulder and hunchback flat shoulder. The neck-shoulder shape could be automatically recognized based on the established classification rules and two-dimensional (2D) body measurement method, with an accuracy rate of 90%. The neck-shoulder shape automatic recognition system constructed based on this method is effective.

Originality/value

This study proposed a simple neck-shoulder automatic recognition method based on the 2D body images. This approach can be extended to other group of human body or other parts of the body.
Entrepreneurial orientation during adversity: differences across ownership categories
Authors: Mondal Arindam , Chakrabarti Amit Baran
Published: March 2021

Purpose

This study seeks to highlight the dynamic nature of entrepreneurial orientation (EO) by investigating how firms respond to adversity, i.e. performance below aspiration levels through pertinent changes in EO, and if some of these changes can be accounted for based on the ownership of the firm.

Design/methodology/approach

This study adopts a multiple regression using an ordinary least square methodology on a sample of 13,333 Indian firms within the period 2005–2016 to test its hypothesis.

Findings

This research sheds light on performance feedback as an antecedent to EO as also on the effect of ownership moderating this relationship, with diversity in resource configuration and governance arrangement being the key drivers.

Research limitations/implications

This is a single country study; hence, there is a possibility of a country-specific bias. This study uses a secondary measure of EO and thus is unable to capture the entrepreneurial intentions and opinions of managers.

Practical implications

The study establishes a nuanced understanding of how ownership impacts the entrepreneurial behaviour of firms during times of adversity.

Social implications

This study may help policymakers draft appropriate policy interventions for firms at the time of adversity, so that they can improve their entrepreneurial spree.

Originality/value

This rare study from an emerging market establishes performance feedback as an important antecedent of EO. It further highlights the vital role of ownership in supporting/constraining EO.
Measuring the efficiency of the healthcare sector in Poland – a window-DEA evaluation
Authors: Miszczynska Katarzyna , Miszczyński Piotr Marek
Published: March 2021

Purpose

The main aim of the study was to measure and assess the efficiency of the healthcare system in Poland.

Design/methodology/approach

An output-oriented Data Envelopment Analysis model with a 2-years window analysis extension was used between 2013 and 2018. The analysis was completed with a determination of the sources of productivity changes (between the first and last year of the study period) and factors that influence efficiency.

Findings

Efficient regions have been identified and the spatial diversity in their efficiency was confirmed. The study identified individual efficiency trends together with “all-windows” best and worst performers. Using panel modeling, it was confirmed that the efficiency of health protection is influenced by, among others, accreditation certificates, the length of the waiting list or the number of medical personnel.

Research limitations/implications

Although the analysis was conducted at the voivodeship level (NUTS2), which was fully justified, it would be equally important to analyze data with a lower aggregation level. It would be extremely valuable from the perspective of difficulties faced by the healthcare system in Poland.

Practical implications

The identification of areas and problems affecting the efficiency of the healthcare system in Poland may also be a hint for other countries with similar system solutions that also struggle with the same problems.

Originality/value

The paper explains the efficiency of the country's healthcare system while also paying attention to changes in its level, factors influencing it, spatial diversity and impact on the sector functioning.
Performance measure of maintenance practices for F-16 fighter jets by data envelopment analysis
Authors: Hur Mansik , Joo Seong-Jong , Cho Jaeyoung
Published: March 2021

Purpose

The purpose of this study is to provide the benchmarking guideline to improve managing maintenance man-hour in producing sorties of fighter jet aircraft in the Korean Air Force by measuring relative efficiency of aircraft in a fleet.

Design/methodology/approach

Using actual operational data from 2014 to 2018, this paper measures the relative efficiencies of aircraft by data envelopment analysis (DEA) model. To analyze the efficiencies across different operational units and among aircraft with different attributes, non-parametric statistical techniques and tobit regression are employed.

Findings

The overall management of maintenance man-hour turns out to be 63.2% efficient compared to the best practice. Operational unit possessing aircraft with different configurations shows the poorest performance implying efficiency depends on the complexity of job processes. Identification of aircraft on the best-practice frontier indicates the efficiency is closely related with the reliability of components and the age of aircraft.

Practical implications

Performance of aircraft maintenance has a tremendous impact on military readiness, utilization of work force, and the quality and safety of flight operations. This study confirmed there exists plenty of room for performance enhancement and presents a reference to find a balance in the performances of maintenance practices across different installations as well as among different types of aircraft.

Originality/value

Application of DEA to engineering systems has been limited in literature, especially in military operations. Thus, this study presents meaningful guidelines to which fleet manager can refer to when establishing strategic maintenance plans to balance the utilization of manpower.
From fun-lovers to institutionalists: uncovering pluralism in IT occupational culture
Authors: Cranefield Jocelyn , Gordon Mary Ellen , Palvia Prashant , Serenko Alexander , Jacks Tim
Published: March 2021

Purpose

The study aims to explore whether there is diversity of occupational culture among IT workers. Prior work conceptualizes IT occupational culture (ITOC) as based around six distinctive values (ASPIRE) but has not explored whether there is variation in ITOC.

Design/methodology/approach

Survey data from 496 New Zealand IT workers was used to create factors representing IT occupational values based on the ASPIRE tool. Hierarchical cluster analysis and discriminant analysis were applied to identify distinctive segments of ITOC.

Findings

Four ITOC segments were identified: fun-lovers, innovators, independents and institutionalists. These differed in the relative emphasis ascribed to the ITOC values with each segment being distinguished by 1–2 dominant values. Segment membership varied according to level of responsibility and birth country. Institutionalists and innovators had higher concern about organizational and IT issues than fun-lovers and independents. Job satisfaction was lowest among innovators and highest along institutionalists.

Research limitations/implications

This study challenges the concept of a unified ITOC, suggesting that ITOC is pluralistic. It also theorizes about interactions between ITOC, individual motivation and values and national culture.

Practical implications

Management needs to be cognizant of the fact that IT occupational culture is not homogeneous and different IT occupational segments require unique management approaches, and that their own values may not match those of others in IT work. By understanding ITOC segments, managers can tailor support, assign tasks appropriately and design teams to optimize synergies and avoid conflict.

Originality/value

This study reveals the existence of ITOC segments and theorizes about the relationship of these to innovation-orientation, job satisfaction, individual motivation, work styles and national culture. The combination of cluster and discriminant analysis is a valuable replicable inductive method that is underrepresented in Information Systems (IS) research.
Museum engagement visits with a universal game-based blended museum learning service for different age groups
Authors: Hsu Tien-Yu , Liang Hsin-Yi
Published: March 2021

Purpose

This study develops a universal game-based blended museum learning service (UGBMLS) to engage museum visitors of different ages and promote their return visits. This study aims to provide a single service with flexible learning content matching the diverse needs and preferences for different ages. The contextual influences are considered to promote participatory experiences and meaningful social interactions. An experiment is conducted herein to understand how visitors of different ages experience the museum's services as well as to address the design issues in aiming to satisfy the different age groups' needs.

Design/methodology/approach

A UGBMLS, which includes a real-world adventure game system with flexible learning content and various types of learning support, was provided for different age groups. To investigate how the visitors of different ages evaluate their experiences with the UGBMLS, a mixed-method study was conducted. In total, two questionnaires were employed to examine the visitors' museum experiences and subjective measurements of cognitive load. In addition, observation and group interviews were used to explain the quantitative results.

Findings

The results show that the UGBMLS can engage diverse visitors of different ages in museum visits and promote their revisit motivations. However, there are significant differences among different age groups. The design issues in seeking to satisfy the diverse needs of different age groups are noted.

Practical implications

This study provides a feasible and cost-effective approach to support diverse visitors of different ages learning in museums.

Originality/value

This study provides an effective solution for engaging diverse visitors of different ages with a unified service. The results can be used to better understand the needs of different age groups and to effectively improve their museum experiences, thereby boosting their motivation regarding return visits. This study provides a feasible and cost-effective approach to support diverse visitors' learning in museums.
IPO underpricing and long-term performance in China: the perspective of price limit policy
Authors: Wang Yuxin , Wang Guanying
Published: March 2021

Purpose

The purpose of this paper is to explore how the price limit policy implemented in 2014 affects initial public offering (IPO) underpricing and long-term performance in China.

Design/methodology/approach

The data are the IPOs from Shanghai Stock Exchange (SSE) and Shenzhen Stock Exchange (SZSE) between 2004 and 2018. The data are firstly divided into the IPOs before the price limit policy and the IPOs after the price limit policy according to the time of issuance. Then the two groups are divided into 4 subsamples according to the market blocks and the P/E ratio. The authors use multiple regression models to explore the effect of price limit policy in each subsample.

Findings

The first-day price limit system for IPOs is similar to the upward fuse mechanism, the purpose of which is to suppress IPO underpricing. However, this study finds that the policy does not suppress IPO underpricing, but increases the underpricing rate in all subsamples. Besides, the long-term performance in each subsample is different from each other. Main Board stocks’ long-term performance is worse after the policy. The policy makes Small and Medium Enterprise Board (SME Board) and Growth Enterprise Market Board (GEM Board) stocks with high P/E ratios perform better in the long term. For SME Board and GEM Board stocks with low P/E ratios, the policy makes no significant effect.

Practical implications

Good policy intentions may sometimes lead to counterproductive effects. However, since the long-term performance of each subsample is different, it is difficult to judge whether the policy should continue to be implemented or cancelled. Implementing different policies for different subsamples may be a better way to solve this problem.

Originality/value

This paper contributes to the study of IPO underpricing and long-term performance from the perspective of price limit policy.
An empirical investigation on the impact of capital structure on firm performance: evidence from Malaysia
Authors: Ayaz Muhammad , Mohamed Zabri Shafie , Ahmad Kamilah
Published: March 2021

Purpose

The purpose of this study is to examine the relationships between leverage and firm’s performance in Malaysia by framing the relationship under the tradeoff theory and agency cost theory.

Design/methodology/approach

Based on insights drawn from the existing literature, we opted for fixed effects and system two-steps GMM models to establish the hypothesized relationship between leverage and performance. We analyzed 528 nonfinancial firms listed on the Bursa Malaysia Stock exchange for the period of 12 years (2005–2016).

Findings

The outcomes show that the leverage ratio improves the firm performance, consistent with leverage serving as an effective strategy in constraining managers from building their personal empire, revealing a proportionately greater benefit for Malaysian firms than the cost to debt financing. The authors also find that a positive relationship between leverage and firm performance switch to the negative when the level of leverage reaches beyond the optimal level. Consequently, switching from positive to negative indicates that debt has a twofold (nonlinear) impact on firm performance.

Practical implications

Our research provides several implications to potential stakeholders. For investors, firms having lower leverage ratios could achieve superior performance, thus investing in corporations pursuing higher performance. Managers should therefore strive for achieving higher performance to meet the needs of investors and shareholders. From the researcher’s perspective, our research suggests the need to go away from the searching linear association between leverage and firm performance and the relevance of nonlinear correlation. Moreover, our research can help managers to understand how their lender relates to their debt to assets ratios. Thus, they can design an optimal level of leverage that not only improves the firm’s performance but also reduce the associated costs.

Originality/value

To the best of the author’s knowledge, this is the initial attempt in the context of Malaysia that documents evidence indicating that the lower leverage is likely to create value for shareholders while a higher debt ratio reduces firm profitability.
Alleviating state boredom through search for meaning and affirmation of workplace heroes
Authors: Dharani Babar , Giannaros Margaux , April Kurt
Published: March 2021

Purpose

Employee boredom is of concern to organizations because of its impact on employees’ quality of work life and productivity. This study aims to test the regulation of workplace boredom through meaning in life by workplace heroes to contribute to theory by examining the relationships between the variables and to practice by uncovering the potential of workplace heroes in alleviating state boredom.

Design/methodology/approach

Using online surveys and structured interviews for a mixed-method study, data were collected for state boredom, meaning in life and hero affirmation at work for a quantitative study, and data from the open-ended questions provided further insights regarding hero affirmation at work for a qualitative study.

Findings

Spearman rank-order correlations concluded correlations between state boredom and meaning in life. However, unlike personal heroes that influence meaning in life, workplace heroes were found not to. The qualitative analysis revealed three prime differences between workplace and personal heroes: proximity, symbolic representation of ideologies and qualities admired in the heroes. These reasons entailed that state boredom was not regulated by workplace heroes.

Originality/value

The model of Coughlan et al. (2019) explored trait boredom regulation through meaning in life by personal heroes. This study tested for the regulation of state boredom through meaning in life by workplace heroes; thus, contributing to theory through a nuanced model with enhanced usefulness in practice. The study also further dissects the concept of heroes by uncovering differences between workplace and personal heroes that perpetrated the differences in the findings.
Decision-making, leadership and performance links in private education institutes
Authors: Torlak Nuri Gökhan , Demir Ahmet , Budur Taylan
Published: March 2021

Purpose

This paper aims to investigate the relationships between participative decision-making, ethical leadership and leadership performance, which might make school leaders quit autocratic behavior and enhance their performance at private K12 schools in Iraq.

Design/methodology/approach

The researchers collected data through a questionnaire using a stratified sampling methodology from 207 educators of 10 institutions. The research methodology included demographic analysis, factor analysis, structural equation modeling and mediation analysis.

Findings

The participative decision-making affected moral, knowledge and attitude that contributed to leadership performance. Besides, the only attitude mediated the relationship between participative decision-making and leadership performance.

Research limitations/implications

The study is limited to private K12 schools in Iraq. Therefore, the findings cannot be generalized. It might guide educational institutes to change their management style.

Originality/value

The study delivers a unique insight into education in Iraq.