bluuebunny/crossref_metadata_2025 huggingface dataset:
ACE2 interaction networks in COVID-19: a physiological framework for prediction of outcome in patients with cardiovascular risk factors
Authors: Wicik Zofia , Eyileten Ceren , Jakubik Daniel , Simões Sérgio N , Martins David C , Pavão Rodrigo , Siller-Matula Jolanta M. , Postula Marek
Published: May 2020

(1)

Background

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection (coronavirus disease 2019; COVID-19) is associated with adverse outcomes in patients with cardiovascular disease (CVD). The aim of the study was to characterize the interaction between SARS-CoV-2 and Angiotensin-Converting Enzyme 2 (ACE2) functional networks with a focus on CVD.;

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Methods

Using the network medicine approach and publicly available datasets, we investigated ACE2 tissue expression and described ACE2 interaction networks which could be affected by SARS-CoV-2 infection in the heart, lungs and nervous system. We compared them with changes in ACE-2 networks following SARS-CoV-2 infection by analyzing public data of stem cell-derived cardiomyocytes (hiPSC-CMs). This analysis was performed using the NERI algorithm, which integrates protein-protein interaction with co-expression networks. We also performed miRNA-target predictions to identify which ones regulate ACE2-related networks and could play a role in the COVID19 outcome. Finally, we performed enrichment analysis for identifying the main COVID-19 risk groups.

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Results

We found similar ACE2 expression confidence levels in respiratory and cardiovascular systems, supporting that heart tissue is a potential target of SARS-CoV-2. Analysis of ACE2 interaction networks in infected hiPSC-CMs identified multiple hub genes with corrupted signalling which can be responsible for cardiovascular symptoms. The most affected genes were EGFR, FN1, TP53, HSP90AA1, and APP, while the most affected interactions were associated with MAST2 and CALM1. Enrichment analysis revealed multiple diseases associated with the interaction networks of ACE2, especially cancerous diseases, obesity, hypertensive disease, Alzheimer’s disease, non-insulin-dependent diabetes mellitus, and congestive heart failure. Among affected ACE2-network components connected with SARS-Cov-2 interactome, we identified AGT, CAT, DPP4, CCL2, TFRC and CAV1, associated with cardiovascular risk factors. We described for the first time miRNAs which were common regulators of ACE2 networks and virus-related proteins in all analyzed datasets. The top miRNAs were miR-27a-3p, miR-26b-5p, miR-10b-5p, miR-302c-5p, hsa-miR-587, hsa-miR-1305, hsa-miR-200b-3p, hsa-miR-124-3p, and hsa-miR-16-5p.;

(4)

Conclusion

Our study provides a complete mechanistic framework for investigating the ACE2 network which was validated by expression data. This framework predicted risk groups, including the established ones, thus providing reliable novel information regarding the complexity of signalling pathways affected by SARS-CoV-2. It also identified miR which could be used in personalized diagnosis in COVID-19.
Single cell analysis of the cellular heterogeneity and interactions in the injured mouse spinal cord
Authors: Milich Lindsay M , Choi James , Ryan Christine , Yahn Stephanie L , Tsoulfas Pantelis , Lee Jae K
Published: May 2020

The wound healing process that occurs after spinal cord injury is critical for maintaining tissue homeostasis and limiting tissue damage, but eventually results in a scar-like environment that is not conducive to regeneration and repair. A better understanding of this dichotomy is critical to developing effective therapeutics that target the appropriate pathobiology, but a major challenge has been the large cellular heterogeneity that results in immensely complex cellular interactions. In this study, we used single cell RNA sequencing to assess virtually all cell types that comprise the mouse spinal cord injury site. In addition to discovering novel subpopulations, we used expression values of receptor-ligand pairs to identify signaling pathways that potentially drive specific cellular interactions during angiogenesis, gliosis, and fibrosis. Our dataset is a valuable resource that provides novel mechanistic insight into the pathobiology of not only spinal cord injury, but also other traumatic disorders of the CNS.
Huge and variable diversity of episymbiotic CPR bacteria and DPANN archaea in groundwater ecosystems
Authors: He Christine , Keren Ray , Whittaker Michael , Farag Ibrahim F. , Doudna Jennifer , Cate Jamie H. D. , Banfield Jillian
Published: May 2020

Candidate Phyla Radiation (CPR) bacteria and DPANN archaea are uncultivated, small-celled symbionts often detected in groundwater. However, variations in CPR/DPANN organism abundance, distribution, taxonomic diversity, and degree/nature of host association with groundwater chemistry remain understudied. Here, we performed genome-resolved metagenomic characterization of one agriculturally-impacted and seven pristine groundwater microbial communities in California, recovering 746 dereplicated CPR and DPANN genomes. Our finding of up to 31% CPR bacteria and 4% DPANN archaea in the pristine sites, which serve as local sources of drinking water, may hold health relevance, given growing awareness of the presence of CPR/DPANN organisms in human microbiomes and their association with disease. There is little species-level genome overlap across groundwater sites, indicating that CPR and DPANN communities are highly differentiated according to host populations and physicochemical conditions. Cryo-TEM imaging and genomic analyses indicate that CPR growth may be stimulated by attachment to the surface of host cells, and identified CPR and DPANN lineages with particularly prevalent and/or resilient host cell attachment. These results establish the huge but site-specific diversity of CPR bacteria and DPANN archaea coexisting with diverse hosts in groundwater aquifers, and raise important questions about potential impacts on human health.
Kidney single-cell atlas reveals myeloid heterogeneity in progression and regression of kidney disease
Authors: Conway Bryan R , O’Sullivan Eoin D , Cairns Carolynn , O’Sullivan James , Simpson Daniel J. , Salzano Angela , Connor Katie , Ding Peng , Humphries Duncan , Stewart Kevin , Teenan Oliver , Henderson Neil C , Benezech Cecile , Ramachandran Prakash , Ferenbach David , Hughes Jeremy , Chandra Tamir , Denby Laura
Published: May 2020

The kidney has a limited capacity to repair following injury, however, the endogenous reparative pathways are not well understood. Here we employ integrated droplet- and plate-based scRNA-seq in the murine reversible unilateral ureteric obstruction model to dissect the transcriptomic landscape at the single cell level during renal injury and resolution of fibrosis. We generate a comprehensive catalogue of the changes induced during injury and repair, revealing significant myeloid cell heterogeneity, which would not have been identifiable by conventional flow cytometry. We identify new markers for the myeloid populations within the kidney as well as identification of novel subsets including anArg1+monocyte population specific to early injury and aMmp12+macrophage subset exclusive to repair. Finally, using paired blood exchange to track circulating immune cells, we confirm that monocytes are recruited to the kidney early after injury and are the source ofCcr2+macrophages that accumulate in late injury. Our data demonstrate the utility of complementary technologies to identify novel myeloid subtypes that may represent therapeutic targets to inhibit progression or promote regression of kidney disease.
Rapid diffusion of large TatA complexes detected using single particle tracking microscopy
Authors: Varadarajan Aravindan , Oswald Felix , Lill Holger , Peterman Erwin J.G. , Bollen Yves J. M.
Published: May 2020

The twin-arginine translocation (Tat) system transports folded proteins across the cytoplasmic membrane of most bacteria and archaea. TatA, which contains a single membrane-spanning helix, is believed to be responsible for the actual translocation. According to the prevalent model, multiple TatA subunits form a transient protein-conducting pore, which disassembles after each translocation event. An alternative model exists, in which TatA proteins locally weaken the lipid bilayer to translocate folded proteins. Here, we imaged eGFP-fused TatA expressed from the genome in liveE. colicells. Images showed TatA occuring both in highly mobile monomers or small oligomers and in large, stable complexes that do not dissociate. Single-particle tracking revealed that large TatA complexes switch between fast and slow diffusion. The fast diffusion is too fast for a transmembrane protein complex consisting of multiple TatA monomers. In line with recent data on rhomboid proteases, we propose that TatA complexes switch between a slowly diffusing transmembrane conformation and a rapidly diffusing membrane-disrupting state that enables folded proteins to cross the membrane, in accordance with the membrane-weakening model.
Growth factor receptor signaling inhibition prevents SARS-CoV-2 replication
Authors: Klann Kevin , Bojkova Denisa , Tascher Georg , Ciesek Sandra , Münch Christian , Cinatl Jindrich
Published: May 2020

SARS-CoV-2 infections are rapidly spreading around the globe. The rapid development of therapies is of major importance. However, our lack of understanding of the molecular processes and host cell signaling events underlying SARS-CoV-2 infection hinder therapy development. We employed a SARS-CoV-2 infection system in permissible human cells to study signaling changes by phospho-proteomics. We identified viral protein phosphorylation and defined phosphorylation-driven host cell signaling changes upon infection. Growth factor receptor (GFR) signaling and downstream pathways were activated. Drug-protein network analyses revealed GFR signaling as key pathway targetable by approved drugs. Inhibition of GFR downstream signaling by five compounds prevented SARS-CoV-2 replication in cells, assessed by cytopathic effect, viral dsRNA production, and viral RNA release into the supernatant. This study describes host cell signaling events upon SARS-CoV-2 infection and reveals GFR signaling as central pathway essential for SARS-CoV-2 replication. It provides with novel strategies for COVID-19 treatment.
DNN-Assisted Statistical Analysis of a Model of Local Cortical Circuits
Authors: Zhang Yaoyu , Young Lai-Sang
Published: May 2020

This paper is about the use of Deep Neural Networks (DNN) to assist in the statistical analysis of a network of a few hundred integrate-and-fire neurons intended to model local circuits in the cerebral cortex. Using training data produced by direct numerical simulations, our first task was to discover, with the aid of a DNN, the mapping that yields model response for each set of parameters and input values. After evaluating the performance of the DNN surrogate both in the accuracy of its outputs and in its performance in parameter tuning, we analyzed the outputs of the well-trained DNN to gain insight into local circuits as basic cortical computational units. Because the DNN surrogate computed with vastly higher speeds than actual simulations of the neuronal network, we were able to sample large sets of parameters and input values to produce a broad statistical picture of input-output relations. One of the aims of this paper is to demonstrate that statistical analyses of this kind can provide general theoretical information on model behavior as well as suggest cortical mechanisms. Among our results are the following: Through a derivative analysis of model responses we identified a certain dichotomy in the behavior of I-neurons, leading to a characterization of high gain states which in turn offered insight into mechanisms for surround suppression. A second-derivative analysis revealed limitations of models of integrate-and-fire neurons, namely their inability to replicate the nonlinearities in gain curves observed in real neurons.

Author summary

Local circuits are basic computational units of the cerebral cortex, and statistical analysis of detailed models of such circuits will shed light on cortical computation. Because analytical tools are either overly simplistic or not applicable, systematic numerical exploration of high-dimensional parameter space is not feasible and simulation-based arguments are seldom more than heuristic, we propose in this paper a data-driven DNN-assisted approach that falls into the general framework of surrogate-based modeling. We consider as a test case a network of integrate-and-fire neurons intended to model local circuits in cortex. With the help of an accurate yet extremely efficient DNN surrogate, we reveal the statistics of model response, providing a detailed picture of model behavior. The information obtained is both general and of a fundamental nature, with direct application to neuroscience. Our results suggest that the methodology proposed can be scaled up to larger and more complex neuronal models.
Potential mechanisms of action of celastrol against rheumatoid arthritis: transcriptomic and proteomic analysis
Authors: Song Xinqiang , Dai Erqin , Zhang Yu , Du Hongtao , Wang Lei , Yang Ningning
Published: May 2020

Background

The natural triterpene celastrol exhibits potential anti-inflammatory activity in inflammatory diseases such as rheumatoid arthritis (RA).

Methods

Here we explored through what proteins and processes celastrol may act in activated fibroblast-like synoviocytes (FLS) from RA patients. Differential expression of genes and proteins after celastrol treatment of FLS was examined using RNA sequencing, label-free relatively quantitative proteomics and molecular docking.

Results

Expression of 26,565 genes and 3,372 proteins was analyzed. Celastrol was associated with significant changes in genes that respond to oxidative stress and oxygen levels, as well as genes that stabilize or synthesize components of the extracellular matrix.

Conclusions

These results identify several potential mechanisms through which celastrol may inhibit inflammation in RA.
Iron Chelator-Mediated Anoxic Biotransformation of Lignin by Novel sp.,Tolumonas lignolyticaBRL6-1
Authors: Chaput Gina , Billings Andrew , DeDiego Lani , Orellana Roberto , Adkins Joshua N , Nicora Carrie , Chu Rosalie , Simmons Blake , DeAngelis Kristen M.
Published: May 2020

Lignin is the second most abundant carbon polymer on earth and despite having more fuel value than cellulose, it currently is considered a waste byproduct in many industrial lignocellulose applications. Valorization of lignin relies on effective and green methods of delignification, with a growing interest in the use of microbes. Here we investigate the physiology and lignin biotransformation mechanisms of the novel facultative anaerobic bacterium,Tolumonas lignolyticaBRL6-1, under anoxic conditions. Physiological and biochemical changes were compared between cells grown anaerobically in either lignin-amended or unamended conditions. In the presence of lignin, BRL6-1 had a higher biomass and shorter lag phase compared to unamended conditions, and 14% of the proteins determined to be significantly higher in abundance by log2fold-change of 2 or greater were related to Fe(II) transport in early exponential phase. Ferrozine assays of the supernatant (<10 kDa fraction) confirmed that Fe(III) was bound to lignin and reduced to Fe(II) only in the presence of BRL6-1, suggesting redox activity by the cells. LC-MS/MS analysis of the secretome showed an extra band at 20 kDa in lignin-amended conditions. Protein sequencing of this band identified a protein of unknown function with homology to enzymes in the radical SAM superfamily. Expression of this protein in lignin-amended conditions suggests its role in radical formation. From our findings, we suggest that BRL6-1 is using a protein in the radical SAM superfamily to interact with the Fe(III) bound to lignin and reducing it to Fe(II) for cellular use, increasing BRL6-1 yield under lignin-amended conditions. This interaction potentially generates organic free radicals and causes a radical cascade which could modify and depolymerize lignin. Further research should clarify the extent to which this mechanism is similar to previously described aerobic chelator-mediated Fenton chemistry or radical producing lignolytic enzymes, such as lignin peroxidases, but under anoxic conditions.
Microtubule re-organization during female meiosis inC. elegans
Authors: Lantzsch Ina , Yu Che-Hang , Chen Yu-Zen , Zimyanin Vitaly , Yazdkhasti Hossein , Lindow Norbert , Szentgyörgyi Erik , Pani Ariel , Prohaska Steffen , Srayko Martin , Fürthauer Sebastian , Redemann Stefanie
Published: May 2020

The female meiotic spindles of most animals are acentrosomal and undergo striking morphological changes while transitioning from metaphase to anaphase. The ultra-structure of acentrosomal spindles, and how changes to this structure correlate with such dramatic spindle rearrangements remains largely unknown.

To address this, we applied light microscopy, large-scale electron tomography and mathematical modeling of female meioticC. elegansspindles undergoing the transition from metaphase to anaphase. Combining these approaches, we find that meiotic spindles are dynamic arrays of short microtubules that turn over on second time scales. The results show that the transition from metaphase to anaphase correlates with an increase in the number of microtubules and a decrease in their average length. Detailed analysis of the tomographic data revealed that the length of microtubules changes significantly during the metaphase-to-anaphase transition. This effect is most pronounced for those microtubules located within 150 nm of the chromosome surface. To understand the mechanisms that drive this transition, we developed a mathematical model for the microtubule length distribution that considers microtubule growth, catastrophe, and severing. Using Bayesian inference to compare model predictions and data, we find that microtubule turn-over is the major driver of the observed large-scale reorganizations. Our data suggest that in metaphase only a minor fraction of microtubules, those that are closest to the chromosomes, are severed. The large majority of microtubules, which are not in close contact with chromosomes, do not undergo severing. Instead, their length distribution is fully explained by growth and catastrophe alone. In anaphase, even microtubules close to the chromosomes show no signs of cutting. This suggests that the most prominent drivers of spindle rearrangements from metaphase to anaphase are changes in nucleation and catastrophe rate. In addition, we provide evidence that microtubule severing is dependent on the presence of katanin.
Spatio-temporal patterning of living cells with extracellular DNA programs
Authors: Van Der Hofstadt Marc , Galas Jean-Christophe , Estevez-Torres André
Published: May 2020

Reactive extracellular media focus on engineering reaction networks outside the cell to control intracellular chemical composition across time and space. However, current implementations lack the feedback loops and out-of-equilibrium molecular dynamics for encoding spatio-temporal control. Here, we demonstrate that enzyme-DNA molecular programs combining these qualities are functional in an extracellular medium where human cells can grow. With this approach, we construct an internalization program that delivers fluorescent DNA inside living cells and remains functional for at least 48 h. Its non-equilibrium dynamics allows us to control both the time and position of cell internalization. In particular, a spatially inhomogeneous version of this program generates a tunable reaction-diffusion two-band pattern of cell internalization. This demonstrates that a synthetic extracellular program can provide temporal and positional information to living cells, emulating archetypal mechanisms observed during embryo development. We foresee that non-equilibrium reactive extracellular media could be advantageously applied toin vitrobiomolecular tracking, tissue engineering or smart bandages.
Cellular taxonomy and spatial organization of the ventral posterior hypothalamus reveals neuroanatomical parcellation of the mammillary bodies
Authors: Mickelsen Laura E. , Flynn William F. , Springer Kristen , Wilson Lydia , Beltrami Eric J. , Bolisetty Mohan , Robson Paul , Jackson Alexander C.
Published: May 2020

The ventral posterior hypothalamus (VPH) is an anatomically complex brain region implicated in arousal, reproduction, energy balance and memory processing. However, neuronal cell type diversity within the VPH is poorly understood, an impediment to deconstructing the roles of distinct VPH circuits in physiology and behavior. To address this question, we employed a droplet-based single cell RNA sequencing (scRNA-seq) approach to systematically classify molecularly distinct cell types in the mouse VPH. Analysis of >16,000 single cells revealed 20 neuronal and 18 non-neuronal cell populations, defined by suites of discriminatory markers. We validated differentially expressed genes in a selection of neuronal populations through fluorescencein situhybridization (FISH). Focusing on the mammillary bodies (MB), we discovered transcriptionally-distinct clusters that exhibit a surprising degree of segregation within neuroanatomical subdivisions of the MB, while genetically-defined MB cell types project topographically to the anterior thalamus. This single cell transcriptomic atlas of cell types in the VPH provides a detailed resource for interrogating the circuit-level mechanisms underlying the diverse functions of VPH circuits in health and disease.
Decreased cued fear discrimination learning in female rats as a function of estrous phase
Authors: Trask Sydney , Reis David S. , Ferrara Nicole C. , Helmstetter Fred J.
Published: May 2020

Relative to males, female rats can show enhanced contextual fear generalization (demonstrating a fear response in a safe or neutral context) dependent on estrogen receptor activation. The current experiment aimed to extend this finding to cued fear conditioning. Females in low-estrogen phases of the estrous cycle showed good discrimination, similar to males, between a conditional stimulus that predicted shock (CS+) and an equally familiar one that did not (CS−), while females in the proestrus (high estrogen) phase demonstrated similar levels of fear between the CS+ and CS−. These results demonstrate that cued fear generalization is similarly influenced by endogenous estrogens.
Computational model of the distributed representation of operant reward memory: combinatoric engagement of intrinsic and synaptic plasticity mechanisms
Authors: Costa Renan M. , Baxter Douglas A. , Byrne John H.
Published: May 2020

Operant reward learning of feeding behavior inAplysiaincreases the frequency and regularity of biting, as well as biases buccal motor patterns (BMPs) toward ingestion-like BMPs (iBMPs). The engram underlying this memory comprises cells that are part of a central pattern generating (CPG) circuit and includes increases in the intrinsic excitability of identified cells B30, B51, B63, and B65, and increases in B63–B30 and B63–B65 electrical synaptic coupling. To examine the ways in which sites of plasticity (individually and in combination) contribute to memory expression, a model of the CPG was developed. The model included conductance-based descriptions of cells CBI-2, B4, B8, B20, B30, B31, B34, B40, B51, B52, B63, B64, and B65, and their synaptic connections. The model generated patterned activity that resembled physiological BMPs, and implementation of the engram reproduced increases in frequency, regularity, and bias. Combined enhancement of B30, B63, and B65 excitabilities increased BMP frequency and regularity, but not bias toward iBMPs. Individually, B30 increased regularity and bias, B51 increased bias, B63 increased frequency, and B65 decreased all three BMP features. Combined synaptic plasticity contributed primarily to regularity, but also to frequency and bias. B63–B30 coupling contributed to regularity and bias, and B63–B65 coupling contributed to all BMP features. Each site of plasticity altered multiple BMP features simultaneously. Moreover, plasticity loci exhibited mutual dependence and synergism. These results indicate that the memory for operant reward learning emerged from the combinatoric engagement of multiple sites of plasticity.
Co-crystal structure, Hirshfeld surface analysis and DFT studies of 3,4-ethylenedioxythiophene solvated bis[1,3-bis(pentafluorophenyl)propane-1,3-dionato]copper(II)
Authors: Habuka Yusuke , Takeuchi Emily Ami , Hori Akiko
Published: May 2020

The title complex, Cu(L)2or [Cu(C15HF10O2)2], comprised of one copper ion and two fully fluorinated ligands (L−), was crystallized with 3,4-ethylenedioxythiophene (EDOT, C6H6O2S) as a guest molecule to give in a dichloromethane solution a unique co-crystal, Cu(L)2·3C6H6O2S. In the crystal, the oxygen of one guest molecule, EDOT-1, is coordinated to the metal to give an alternate linear arrangement, and the π-planes of the others, EDOT-2 and EDOT-3, interact weakly with the pentafluorophenyl groups of the complex through arene–perfluoroarene interactions. Head-to-tail columnar and head-to-head dimeric arrangements are observed for EDOT-2 and EDOT-3, respectively, in the crystal. The Hirshfeld surface analysis indicated that the most important contributions for the crystal packing are from the F...F (20.4%), F...H/H...F (24.5%) and F...C/C...F (9.6%) interactions. The density functional theory (DFT) optimized structure at the ωB97X-D 6–31G* level was compared with the experimentally determined molecular structure in the solid state.
An innovation management assessment framework
Authors: Lobo Stanislaus , Samaranayake Premaratne
Published: May 2020

Purpose

This paper proposes an integrated approach for assessing innovation management practices using an innovation management assessment framework, with the application of the innovation management assessment framework at the incubation and firm level.

Design/methodology/approach

Innovation management assessment framework is developed, based on the literature review. An innovation management assessment framework toolkit for training innovation practitioners is proposed as the basis for the framework implementation in the industry. The main approach is to make close alignment of the design for lean six sigma phases within broader innovation and stage-gate model in the innovation management assessment framework.

Findings

The operationalization of the innovation management assessment framework is enabled and supported by an assessment framework and a toolkit for managing innovation.

Practical implications

A roadmap for innovation management and assessment of performance at incubatee/firm level.

Social implications

It provides a tool for developing innovative products and services for incubatees in start-ups, thus fueling the economy. It also has applications for ongoing established businesses.

Originality/value

Innovation of new business development can be made through a well-designed and implemented innovation programme that is aligned with stage-gate and design for lean six sigma phases through the innovation management assessment framework.
The significance of grassroots and inclusive innovation in harnessing social entrepreneurship and urban regeneration
Authors: Duarte Alonso Abel , Kok Seng Kiat , O'Brien Seamus , O'Shea Michelle
Published: May 2020

Purpose

The purpose of this study is to examine the dimensions of inclusive and grassroots innovations operationalised by a social enterprise and the impact of these activities on urban regeneration. To this end, the case of Homebaked in Liverpool, UK, is presented and discussed.

Design/methodology/approach

Face-to-face interviews with members of Homebaked’s management, staff and volunteers were conducted; the interviews were complemented with on-site observations and review of archival information of the social enterprise.

Findings

The data gathered revealed the organisation’s involvement in both types of innovation as a means to achieve long-term urban regeneration related goals. For instance, innovative, strategic and human dimensions, together with the human dimension emerged as key ways of innovating. The impacts of innovative practices comprised encouraging inclusiveness among residents and non-residents, with approaches including hands-on training workshops, job and volunteering opportunities being predominant.

Originality/value

First, the study advances the theoretical and applied understanding of grassroots and inclusive innovation in the context of a social enterprise. For instance, an innovative/strategic and human dimension emerged as predominant ways in which grassroots and inclusive innovation elements were manifested. These dimensions were based on technology uptake, implementation of new product/service concepts or harnessing the skills of local and non-local individuals. Similarly, four dimensions associated with the impacts of these types of innovation were revealed. Second, the study addresses acknowledged gaps in the literature, particularly regarding the limited contributions illuminating processes and determinants of innovation among social enterprises.
Investigating the barriers to building information modeling (BIM) implementation within the Nigerian construction industry
Authors: Olanrewaju Oludolapo Ibrahim , Chileshe Nicholas , Babarinde Sunday Ajiboye , Sandanayake Malindu
Published: May 2020

Purpose

The purpose of this paper is to identify and assess the perceptions of constructional professionals on barriers to implementation of building information modeling (BIM) within the Nigerian construction industry.

Design/methodology/approach

A scoping literature review was conducted to identify the fourteen barriers to implementation of BIM, which were employed to design a questionnaire survey. Data collected were analyzed using descriptive statistics, mean score, Kruskal–Wallis test, analysis of variance and multivariate techniques such as factor analysis.

Findings

The descriptive and empirical analysis demonstrated a disparity of ranking of the 14 barriers factors among the groups; however no statistically significant differences among the 14 barriers to BIM. Based on the mean score ranking results, only three (out of 14) barriers are identified as critical (mean score greater than 3.5): few studies available on BIM and lack of knowledge, inexistence or inadequate government policies, and high cost of implementation. The results of the one-sample t-tests show that they were statistically significant differences in 10 out of 14 barriers as follows: few studies available on BIM and lack of knowledge, lack of demand for use and acceptance of BIM, inadequate contractual coordination, lack of specified standards, cost of data and information sharing, technological availability issues, reluctance of other stakeholders, business and cultural changes, data and intellectual property issues, and interoperability issues. The study, through factor analysis, categorized the fourteen barriers to BIM implementation into four principal factors. The factors are: technology and business-related barriers; training and people-related barriers; cost and standards-related barriers; and process and economic-related barriers.

Practical implications

The identification and assessment of the key barriers to BIM implementation would be useful for the construction professionals and other stakeholder of the construction industry with the view to advance BIM adoption in Nigeria. This could also be extended to other developing countries through considerations of the local economic conditions, given the status of BIM as being in the germinating stage of development in Africa.

Originality/value

The study provides insights on the barriers to BIM implementation across the Nigerian construction sector environments. The innovative aspect of the study is the identification of the ordered and grouped (composite) set of barriers to BIM which could be used to developing appropriate mitigating solutions.
Forty years of Employee Relations – The International Journal: a bibliometric overview
Authors: Kataria Aakanksha , Kumar Satish , Sureka Riya , Gupta Bindu
Published: May 2020

Purpose

This paper examines the leading trends for the journal Employee Relations from 1979 to 2018 upon its completion of 40 years of publication. Through conducting a bibliometric analysis, the article presents the journal's publication and citation structure, prominent themes, significant author keywords and leading articles, authors, institutions and countries since its formation.

Design/methodology/approach

The article focuses on the journal's evolution and subsequent growth patterns during this period. Using the Scopus database, the leading trends in authorship, institutions, countries as well as cited documents along with the articles citing it were analysed to provide an analytic overview of the journal over the period of 1979–2018. The paper presents a graphical visualization of the bibliographic data with bibliographic coupling and co-citation analysis using the visualization tools of similarity viewer software as well.

Findings

The results indicate that the journal is on a progressive trend both in terms of productivity as well as the level of influence in the areas for which it is indexed. The journal receives the maximum influence from the UK, including its most productive authors and institutions. The journal has published research on prominent topics in human resource management, employee relations and the field of industrial relations. It has also published 25 special issues on recent trends in the domain of Human Resource (HR).

Originality/value

This article offers the first comprehensive evaluation of the intellectual structure and research contributions of the journal over its lifespan. The findings of the article are useful for researchers and HR practitioners.
Structural breaks in the central government taxes in India, 1950-1951 to 2013-2014
Authors: Rath Anita
Published: May 2020

Purpose

The purpose of this paper is to find out the factors contributing to major shifts in the growth of tax revenue through the estimation of structural breaks and analysis of major tax regimes. Recent contributions to optimal tax theory and empirical literature on the Laffer curve effect, based on elasticity of taxable income, challenge the settled understanding on the rate-revenue relationship. In this backdrop, the objective of the paper is to find out the relative significance of changes in tax rate, tax base and administrative reforms in affecting the growth of tax revenue in India. The paper considers tax data spanning a period of six and half decades for five major components of direct and indirect taxes (corporation, personal income, customs, excise and service) of the central government of India.

Design/methodology/approach

Unknown break point(s) – single and multiple – in the tax structure are identified by using the Quandt-Andrews and Bai-Perron econometric tests. These tests were conducted for two models of growth of taxes (tax revenue and tax-NDP ratio) estimated using semi-log functions. A simulation exercise was conducted to find out the robustness of the results by varying the trimming parameter and number of breaks. An analytical framework is used to understand the factors associated with these breaks.

Findings

There is more than one break identified for every tax component as per the results of Bai–Perron test. The simulation exercise suggests that estimated breakpoints are mostly robust. Economic growth, structural changes in the economy, simplification and rationalization of tax structure, tax competition, policies such as liberalization have contributed to the changing tax regimes. Results of this study suggest that high tax rates have not been, in particular, detrimental to achieving growth in revenue and factors other than changes in tax rates have been more prominent in bringing about the shifts.

Originality/value

This is, perhaps, the first paper exploring the multiple structural breaks in the fiscal variables in India. It offers an understanding of the changing regimes of central government taxes and the underlying factors for the same.
Forty years review of upstream documents of the Islamic Republic of Iran's health sector on strategic purchasing of advanced-expensive medical equipment
Authors: Bastani Peivand , Tahernezhad Ali , Hakimzadeh Seyyed Mostafa
Published: May 2020

Purpose

According to the importance of strategic purchasing as an effective tool for resource allocation and service procurement, this study examines national laws, regulations and other related documents related to the strategic purchasing of health services related to the advanced medical equipment in Iran.

Design/methodolgy/approach

It was a national qualitative document analysis conducted in 2019 applying content analysis approach. The four-step Scott method was used to include the documents in terms of authenticity, credibility, representation and meaningfulness. After retrieving the related documents, they were coded with the implicit and explicit approach. MAXQDA10 was used for content analysis.

Findings

The findings show that according to the framework of effective factors on the strategic purchasing of health services, seven main factors are determined as the main essential factors in purchasing advanced medical equipment. These factors consist of health care providers, health service buyers, purchaser and service provider contracts, payment mechanisms, organization and management evaluation of health technology including expensive medical equipment and technology-related.

Research limitation/implication

The study had some limitations as follows: the proposed method should be tested and its feasibility has to be investigated through appropriate tools for Iranian insurance companies and those with the similar settings.

Practical implication

The results of this study can shed more light for policy makers affiliated in Ministry of Health as the main service provider, Ministry of Welfare and the insurance agencies as the main purchasers of health services on paying attention to these seven main themes extracted from the upstream documents and laws and regulations of the Islamic Republic of Iran.

Social implication

The strategic purchasing of expensive high technology-based medical equipment is a necessity for Iranian public health insurance organizations that is emphasized in national documents in the way of implementing this necessity.

Originality/value

This study examines all the laws and regulations and all related documents in the strategic purchasing of health services related to advanced medical equipment, giving an analysis of the most important challenges and requirements of implementing strategic purchasing in the health services provision sector with expensive medical equipment.
Obstacle-avoiding intelligent algorithm for quad wheel robot path navigation
Authors: Mukherjee Subhradip , Kumar R. , Borah Siddhanta
Published: May 2020

Purpose

The purpose of this work is to propose quad wheel robot with path navigation using an intelligent novel algorithm named as obstacle-avoiding intelligent algorithm (OAIA).

Design/methodology/approach

The paper proposes OAIA algorithm, which is used to minimize the path distance and elapsed time between source and goal.

Findings

The hardware implementation of the Quad Wheel Robot design includes a global positioning system (GPS) module for path navigation. An ultrasonic module (HC SR04) is mainly used as the sensing unit for the system. In the proposed scheme, the GPS locator (L80) is used to obtain the current location of the robot, and the ultrasonic sensor is utilized to avoid the obstacles. An ARM processor serves as the heart of the Quad Wheel Robot.

Practical implications

This paper includes real-time implementation of quad wheel robot for various coordinate values, and the movement of the robot is captured and analysed.

Originality/value

The proposed OAIA is capable of estimating the mobile robot position exactly under ideal circumstances. Simulation and hardware implementation are carried out to evaluate the performance of the proposed system.
Towards the creation of a searchable 3D smart city model
Authors: Lafioune Nawel , St-Jacques Michèle
Published: May 2020

Purpose

This paper aims to create a new searchable 3D city model to help managers improve their decision-making.

Design/methodology/approach

This paper identifies data management basics and the key elements used in the new model design; it further analyzes five-city models, presents its findings and proposes analytical trends for the new model. It discusses the concepts underlying existing models, explains the benefit brought by the proposed model and demonstrates its robustness.

Findings

City systems can be interconnected, thanks to data digitization and the integration of new technologies into different management processes. Although there are several 3D city models available, none of those identified in this research can be queried for several sectors.

Research limitations/implications

This model design can only be successfully realized in the presence of a public mandate. Potential limitations include information security risks and political non-acceptance.

Originality/value

The present work proposes a searchable and high performance model having the distinctive capacity to bring together city systems and perform real-time data analysis in order to extract important information needed to guide the city, and in the context of a global vision.
Robot-assisted 3D digital reconstruction of heritage artifacts: area similarity approach
Authors: Gothandaraman Rajkumar , Muthuswamy Sreekumar
Published: May 2020

Purpose

This paper aims to propose a system to acquire images automatically for digital reconstruction of heritage artifacts using a six-degree of freedom industrial manipulator.

Design/methodology/approach

A virtual environment is created using Robot Studio® software to integrate the trajectory and differential motion of the robot manipulator and the motion of camera while acquiring images. A new area similarity matrix method is proposed to reduce the number of images required for digital reconstruction using Autodesk Recap® software. Real-time experiments have been performed using objects such as minion, ultimaker robot and cube. Evaluation of the digital reconstruction is conducted using the contour area matching method.

Findings

The number of images required for reconstruction based on area similarity matrix method is reduced to 63 per cent when compared with the random selection method. Quality parameters such as surface area, volume, number of defect holes, vertices and faces are enhanced for the proposed method.

Research limitations/implications

Digital reconstruction of large-sized heritage artifacts cannot be performed in this setup. But this can be overcome by fixing the manipulator on a mobile platform or overhead crane. This paper does not discuss the reconstruction of partially damaged heritage artifacts, which could be accomplished based on deep learning techniques.

Practical implications

Using this approach, off-the-shelf heritage artifacts and large-scale objects can be reconstructed digitally with a minimum number of images and without compromising the quality of original models.

Originality/value

To the best of the authors’ knowledge, area similarity-based approach in 3D digital reconstruction by coupling the kinematics of an industrial manipulator and camera is proposed for the first time. A fully automated digital reconstruction technology to preserve valuable heritage artifacts has been developed. It also highlights the space constraints of the industrial manipulator in digital reconstruction.
Workspace analysis of Cartesian robot system for kiwifruit harvesting
Authors: Au ChiKit , Barnett Joshua , Lim Shen Hin , Duke Mike
Published: May 2020

Purpose

This paper aims to investigate if a Cartesian robot system for kiwifruit harvesting works more effectively and efficiently than an articulated robot system. The robot is a key component in agricultural automation. For instance, multiple robot arm system has been developed for kiwifruit harvesting recently because of the significant labor shortage issue. The industrial robots for factory automation usually have articulated configuration which is suitable for the tasks in the manufacturing and production environment. However, this articulated configuration may not fit for agricultural application due to the large outdoor environment.

Design/methodology/approach

The kiwifruit harvesting tasks are completed step by step so that the robot workspace covers the canopy completely. A two-arm, Cartesian kiwifruit harvesting robot system and several field experiments are developed for the investigation. The harvest cycle time of the Cartesian robot system is compared to that of an articulated robot system. The difference is analyzed based on the workspace geometries of these two robot configurations.

Findings

It is found that the kiwifruit harvesting productivity is increased by using a multiple robot system with Cartesian configuration owing to its regular workspace geometry.

Originality/value

An articulated robot is a common configuration for manufacturing because of its simple structure and the relatively static factory environment. Most of the agricultural robotics research studies use single articulated robot for their implementation. This paper pinpoints how the workspace of a multiple robot system affects the harvest cycle time for kiwifruit harvesting in a pergola style kiwifruit orchard.
Corruption in interaction: the role of social capital in private–public relationships
Authors: Bondeli Julia V. , Havenvid Malena I. , Solli-Sæther Hans
Published: May 2020

Purpose

This paper aims to explore corrupt exchange as a type of socioeconomic interaction in private–public relationships and its effects on material flow in connected private-private relationships.

Design/methodology/approach

The paper is based on a case study of a private–public network of an import firm in Russia. It focusses on corrupt exchange in routine interactions between the firm’s managers and officials in three regulatory authorities.

Findings

The study reveals how different types of corrupt exchange between firm managers, officials and intermediaries serve as a problem-solving tool that facilitates material flow through bureaucratic gates.

Research limitations/implications

The paper contributes to the industrial marketing and purchasing research by showing how the social capital concept is useful for explicating mechanisms of socioeconomic interaction in business networks and how the interaction context conditions actors’ roles and interdependencies.

Practical implications

The paper raises practitioners’ awareness of corrupt exchange in business networks and enables them to anticipate and manage upcoming challenges in bureaucratic procedures.

Social implications

The study shows how networks’ non-transparent and manipulative tendencies may provide favourable conditions for corruption in the business landscape.

Originality/value

The study provides a unique empirical insight into the socioeconomic mechanisms of corrupt exchange in business networks. It contributes theoretically by conceptualising corrupt officials as taking on the role of quasi-business actors in the personal possession of administrative authority as a resource and by using a novel conceptualisation of social capital to study private–public interaction in business networks.