bluuebunny/crossref_metadata_2025 huggingface dataset:
Bacillus velezensis stimulates resident rhizosphere Pseudomonas stutzeri for plant health through metabolic interactions
Authors: Sun Xinli , Xu Zhihui , Xie Jiyu , Thomsen Viktor H. , Tan Taimeng , Strube Mikael L. , Dragoš Anna , Shen Qirong , Zhang Ruifu , Kovács Ákos T.
Published: June 2021

Trophic interactions play a central role in driving microbial community assembly and function. In gut or soil ecosystems, successful inoculants are always facilitated by efficient colonization, however, the metabolite exchanges between inoculants and resident bacteria are rarely studied, particularly in the rhizosphere. Here, we used bioinformatic, genetic, transcriptomic and metabonomic analyses to uncover syntrophic cooperation between inoculant (Bacillus velezensis SQR9) and plant-beneficial indigenous Pseudomonas stutzeri in the cucumber rhizosphere. We found that the synergistic interaction of these two species is highly environmental dependent, the emergence of syntrophic cooperation was only evident in a static nutrient-rich niche, such as pellicle biofilm in addition to the rhizosphere. Our results identified branched-chain amino acids (BCAAs) biosynthesis pathway involved in syntrophic cooperation when forming coculture biofilms. Assaying the metabolome further demonstrated metabolic facilitation among the bacterial strains. In addition, biofilm matrix components from Bacillus were essential for the interaction. Importantly, the two-species consortium promoted plant growth and helped plants alleviate salt stress. In summary, we propose a mechanism in which synergic interactions between a biocontrol bacterium and a partner species promote plant health.
Hypoxia Tolerance Declines with Age in the Absence of Methi-onine Sulfoxide Reductase (MSR) in Drosophila melanogaster
Authors: Suthakaran Nirthieca , Chandran Sanjana , Iacobelli Michael , Binninger David
Published: June 2021

Unlike the mammalian brain, Drosophila melanogaster can tolerate several hours of hypoxia without any tissue injury by entering a protective coma known as spreading depression. However, when oxygen is reintroduced, there is an increased production of reactive oxygen species (ROS) that causes oxidative damage. Methionine sulfoxide reductase (MSR) acts to restore functionality to oxidized methionine residues. In the present study, we have characterized in vivo effects of MSR deficiency on hypoxia tolerance throughout the lifespan of Drosophila. Flies subjected to sudden hypoxia that lacked MSR activity exhibited a longer recovery time and a reduced ability to survive hypoxic stress as they approached senescence. However, when hypoxia was induced slowly, MSR deficient flies recovered significantly quicker throughout their entire adult lifespan. In addition, the wildtype and MSR deficient flies had nearly 100% survival rates throughout their lifespan. Neuro-protective signaling mediated by decreased apoptotic pathway activation, as well as gene reprogramming and metabolic downregulation are possible reasons for why MSR deficient flies have faster recovery time and a higher survival rate upon slow induction of spreading depression. Our data are the first to suggest important roles of MSR and longevity pathways in hypoxia tolerance exhibited by Drosophila.
Kinesin-binding protein remodels the kinesin motor to prevent microtubule-binding
Authors: Solon April L. , Tan Zhenyu , Schutt Katherine L. , Jepsen Lauren , Haynes Sarah E. , Nesvizhskii Alexey I. , Sept David , Stumpff Jason , Ohi Ryoma , Cianfrocco Michael A.
Published: June 2021

Kinesins are tightly regulated in space and time to control their activation in the absence of cargo-binding. Kinesin-binding protein (KIFBP) was recently discovered to bind the catalytic motor heads of 8 of the 45 known kinesin superfamily members and inhibit binding to microtubules. In humans, mutation of KIFBP gives rise to Goldberg-Shprintzen syndrome (GOSHS), but the kinesin(s) that is misregulated to produce clinical features of the disease is not known. Understanding the structural mechanism by which KIFBP selects its kinesin binding partners will be key to unlocking this knowledge. Using a combination of cryo-electron microscopy and crosslinking mass spectrometry, we determined structures of KIFBP alone and in complex with two mitotic kinesins, revealing regions of KIFBP that participate in complex formation. KIFBP adopts an alpha-helical solenoid structure composed of TPR repeats. We find that KIFBP uses a 2-pronged mechanism to remodel kinesin motors and block microtubule-binding. First, KIFBP engages the microtubule-binding interface and sterically blocks interaction with microtubules. Second, KIFBP induces allosteric conformational changes to the kinesin motor head that displace a key structural element in the kinesin motor head (α-helix 4) required for microtubule binding. We identified two regions of KIFBP necessary for in vitro kinesin-binding as well as cellular regulation during mitosis. Taken together, this work establishes the mechanism of kinesin inhibition by KIFBP and provides the first example of motor domain remodeling as a means to abrogate kinesin activity.
What most influences severity and death of COVID-19 patients in Brazil? Is it clinical, social, or demographic factors? An observational study
Authors: Mafra Ana Carolina C. N. , Vieira Régis Rodrigues , Monteiro Camila N. , Cavalcante Denise F. B. , Miraglia João L. , Bonfim Daiana , Palacio Danielle C. , Martins Alessandra C. F. , de Almeida Letícia Yamawaka , Neto João Peres
Published: June 2021

Objective

This study aimed to assess the space distribution and factors associated with the risk of severe acute respiratory syndrome (SARS) and death in COVID-19 patients, based on routine register data; and to develop and validate a predictive model of the risk of death from COVID-19.

Methods

A cross-sectional, epidemiological study of positive SARS-CoV-2 cases, reported in the south region of the city of São Paulo, SP, Brazil, from March 2020 to February 2021. Data were obtained from the official reporting databases of the Brazilian Ministry of Health for influenza-like illness (ILI) (esus-VE, in Portuguese) and for patients hospitalized for SARS (SIVEP-Gripe). The space distribution of cases is described by 2D kernel density. To assess potential factors associated with the outcomes of interest, generalized linear and additive logistic models were adjusted. To evaluate the discriminatory power of each variable studied as well as the final model, C-statistic was used (area under the receiver operating characteristics curve). Moreover, a predictive model for risk of death was developed and validated with accuracy measurements in the development, internal and temporal (March and April 2021) validation samples.

Results

A total of 16,061 patients with confirmed COVID-19 were enrolled. Morbidities associated with a higher risk of SARS were obesity (OR=25.32) and immunodepression (OR=12.15). Morbidities associated with a higher risk of death were renal disease (OR=11.8) and obesity (OR=8.49), and clinical and demographic data were more important than the territory per se. Based on the data, a calculator was developed to predict the risk of death from COVID-19, with 92.2% accuracy in the development sample, 92.3% in the internal validation sample, and 80.0% in the temporal validation sample.

Conclusions

The risk factors for SARS and death in COVID-19 patients seeking health care, in order of relevance, were age, comorbidities, and socioeconomic factors, considering each discriminatory power.
Cell atlas of the regenerating human liver after portal vein embolization
Authors: Brazovskaja Agnieska , Gomes Tomás , Körner Christiane , He Zhisong , Schaffer Theresa , Eckel Julian Connor , Hänsel René , Santel Malgorzata , Denecke Timm , Dannemann Michael , Brosch Mario , Hampe Jochen , Seehofer Daniel , Damm Georg , Camp J. Gray , Treutlein Barbara
Published: June 2021

The liver has the remarkable capacity to regenerate. In the clinic, this capacity can be induced by portal vein embolization (PVE), which redirects portal blood flow resulting in liver hypertrophy in locations with increased blood supply, and atrophy of embolized segments. Here we apply single-cell and single-nucleus transcriptomics on healthy, hypertrophied, and atrophied patient-derived liver samples to explore cell states in the liver during regeneration. We first establish an atlas of cell subtypes from the healthy human liver using fresh and frozen tissues, and then compare post-PVE samples with their reference counterparts. We find that PVE alters portal-central zonation of hepatocytes and endothelial cells. Embolization upregulates expression programs associated with development, cellular adhesion and inflammation across cell types. Analysis of interlineage crosstalk revealed key roles for immune cells in modulating regenerating tissue responses. Altogether, our data provides a rich resource for understanding homeostatic mechanisms arising during human liver regeneration and degeneration.
Transcription-coupled and epigenome-encoded mechanisms direct H3K4 methylation
Authors: Oya Satoyo , Takahashi Mayumi , Takashima Kazuya , Kakutani Tetsuji , Inagaki Soichi
Published: June 2021

Mono-, di-, and trimethylation of histone H3 lysine 4 (H3K4me1/2/3) are associated with transcription, yet it remains controversial whether H3K4me1/2/3 promote or result from transcription. Our previous characterizations of Arabidopsis H3K4 demethylases suggest roles for H3K4me1 in transcription. However, the control of H3K4me1 remains unexplored in Arabidopsis, in which no methylase for H3K4me1 has been identified. Here, we identified three Arabidopsis methylases that direct H3K4me1. Analyses of their genome-wide localization using ChIP-seq and machine learning revealed that one of the enzymes cooperates with the transcription machinery, while the other two are associated with specific histone modifications and DNA sequences. Importantly, these two types of localization patterns are also found for the other H3K4 methylases in Arabidopsis and mice. These results suggest that H3K4me1/2/3 are established and maintained via interplay with transcription as well as inputs from other chromatin features, presumably enabling elaborate gene control.
MutaFrame - an interpretative visualization framework for deleteriousness prediction of missense variants in the human exome
Authors: Ancien François , Pucci Fabrizio , Vranken Wim , Rooman Marianne
Published: June 2021

Motivation

High-throughput experiments are generating ever increasing amounts of various -omics data, so shedding new light on the link between human disorders, their genetic causes, and the related impact on protein behavior and structure. While numerous bioinformatics tools now exist that predict which variants in the human exome cause diseases, few tools predict the reasons why they might do so. Yet, understanding the impact of variants at the molecular level is a prerequisite for the rational development of targeted drugs or personalized therapies.

Results

We present the updated MutaFrame webserver, which aims to meet this need. It offers two deleteriousness prediction softwares, DEOGEN2 and SNPMuSiC, and is designed for bioinformaticians and medical researchers who want to gain insights into the origins of monogenic diseases. It contains information at two levels for each human protein: its amino acid sequence and its 3-dimensional structure; we used the experimental structures whenever available, and modeled structures otherwise. MutaFrame also includes higher-level information, such as protein essentiality and protein-protein interactions. It has a user-friendly interface for the interpretation of results and a convenient visualization system for protein structures, in which the variant positions introduced by the user and other structural information are shown. In this way, MutaFrame aids our understanding of the pathogenic processes caused by single-site mutations and their molecular and contextual interpretation.

Availability

Mutaframe webserver at http://mutaframe.com
Quantifying the effect of A. thaliana root on antibiotic production in the beneficial bacterium, B. subtilis
Authors: Maan Harsh , Gilhar Omri , Porat Ziv , Kolodkin-Gal Ilana
Published: June 2021

Beneficial and probiotic bacteria play an important role in conferring the immunity of their hosts against a wide range of bacterial, viral and fungal diseases. B. subtilis is a bacterium that protects the plant from various pathogens due to its capacity to produce an extensive repertoire of antibiotics. At the same time, the plant microbiome is a highly competitive niche, with multiple microbial species competing for space and resources, a competition that can be determined by the antagonistic potential of each microbiome member. Therefore, regulating antibiotic production in the rhizosphere is of great significance to eliminate pathogens and to establish beneficial host-associated communities.

In this work, we used Bacillus subtilis as a model to investigate the role of plant colonization in antibiotic production. Flow cytometry and Image-stream cytometry analysis supported the notion that A. thaliana specifically induced the transcription of the biosynthetic clusters for the non-ribosomal peptides surfactin, bacilysin and plipastatin and the polyketide bacillaene. This induction could be beneficial for the root as all clusters were shown to antagonize plant pathogens. Consistently, the root failed to induce PenP, a β-lactamase that increases only the fitness of the bacteria. Our results can be translated to improve the performance and competitiveness of beneficial members of the plant microbiome.
Fungal gasdermin-like proteins are controlled by proteolytic cleavage
Authors: Clavé Corinne , Dyrka Witold , Granger-Farbos Alexandra , Pinson Benoît , Saupe Sven J. , Daskalov Asen
Published: June 2021

Gasdermins are a family of pore-forming proteins controlling an inflammatory cell death reaction in the mammalian immune system. The pore-forming ability of the gasdermin proteins is released by proteolytic cleavage with the removal of their inhibitory C-terminal domain. Recently, gasdermin-like proteins have been discovered in fungi and characterized as cell death-inducing toxins in the context of conspecific non-self discrimination (allorecognition). Although functional analogies have been established between mammalian and fungal gasdermins, the molecular pathways regulating gasdermin activity in fungi remain largely unknown. Here, we characterize a gasdermin-based cell death reaction, controlled by the het-Q allorecognition genes in the filamentous fungus Podospora anserina. We show that the cytotoxic activity of the HET-Q1 gasdermin is controlled by proteolysis. HET-Q1 loses a ∼5 kDa C-terminal fragment during the cell death reaction in presence of a subtilisin-like serine protease, termed HET-Q2. Mutational analyses and successful reconstitution of the cell death reaction in a heterologous host (Saccharomyces cerevisiae) suggest that HET-Q2 directly cleaves HET-Q1 to induce cell death. By analysing the genomic landscape of het-Q1 homologs in fungi, we uncovered that the vast majority of the gasdermin genes are clustered with protease-encoding genes. These HET-Q2-like proteins carry either subtilisin-like or caspase-related proteases, which in some cases correspond to the N-terminal effector domain of NOD-like receptor proteins (NLRs). This study thus reveals the proteolytic regulation of gasdermins in fungi and establishes evolutionary parallels between fungal and mammalian gasdermin-dependent cell death pathways.

Significance

The recent discovery of gasdermin-like proteins in fungi have brought to light that this family of pore-forming proteins controls cell death in two of the major eukaryotic kingdoms, fungi and mammals. Yet, the regulation of cytotoxicity of the fungal gasdermins and their molecular pathways remain uncharacterized. Here, we describe the regulation through proteolytic cleavage of the fungal gasdermin HET-Q1 and uncover that majority of fungal gasdermins are genomically clustered with protease-encoding genes. Some of these genes encode proteins with caspase-related domains and/or are members of a family of immune receptors in mammals and plants. Overall, this work contributes towards our understanding of the evolution of gasdermin-dependent cell death, enlightening multiple evolutionary parallels between signaling pathways in mammals and fungi.
New fossils of Jurassic ophiurid brittle stars (Ophiuroidea; Ophiurida) provide evidence for early clade evolution in the deep sea
Authors: Thuy Ben , Numberger-Thuy Lea D. , Pineda-Einríquez Tania
Published: June 2021

1.

Understanding of the evolutionary history of the ophiuroids, or brittle stars, is hampered by a patchy knowledge of the fossil record. Especially the stem members of the living clades are poorly known, resulting in blurry concepts of the early clade evolution and imprecise estimates of divergence ages. Here, we describe new ophiuroid fossil from the Lower Jurassic of France, Luxembourg, and Austria and introduce the new taxaOphiogojira labadieigen. et sp. nov. from lower Pliensbachian shallow sublittoral deposits,Ophiogojira andreuigen. et sp. nov. from lower Toarcian shallow sublittoral deposits, andOphioduplantiera noctilucagen. et sp. nov. from late Sinemurian to lower Pliensbachian bathyal deposits. A Bayesian morphological phylogenetic analysis shows thatOphiogojiraholds a basal position within the order Ophiurida, whereasOphioduplantierahas a more crownward position within the ophiurid family Ophiuridae. The position ofOphioduplantierain the evolutionary tree suggests that family-level divergences within the Ophiurida must have occurred before the late Sinemurian, and that ancient slope environments played an important role in fostering early clade evolution.
Dual control of MAPK activities by AP2C1 and MKP1 MAPK phosphatases regulates defence responses in Arabidopsis
Authors: Ayatollahi Zahra , Kazanaviciute Vaiva , Shubchynskyy Volodymyr , Kvederaviciute Kotryna , Schwanninger Manfred , Rozhon Wilfried , Stumpe Michael , Mauch Felix , Bartels Sebastian , Ulm Roman , Balazadeh Salma , Mueller-Roeber Bernd , Meskiene Irute , Schweighofer Alois
Published: June 2021

Mitogen-activated protein kinase (MAPK) cascades transmit environmental signals and induce stress and defence responses in plants. These signalling cascades are negatively controlled by specific phosphatases of the type 2C Ser/Thr protein phosphatase (PP2C) and dual-specificity phosphatase (DSP) families that inactivate stress-induced MAPKs; however, the interplay between phosphatases of these different types has remained unknown. Our work reveals that different Arabidopsis MAPK phosphatases, the PP2C-type AP2C1 and the DSP-type MKP1, exhibit both specific and overlapping functions in plant stress responses. Each single mutant and ap2c1 mkp1 double mutant displayed enhanced wound-induced activation of MAPKs MPK3, MPK4, and MPK6, as well as induction of a set of transcription factors. Moreover, ap2c1 mkp1 double mutants show an autoimmune-like response, associated with elevated levels the stress hormones salicylic acid and ethylene, and of the phytoalexin camalexin. Interestingly, this phenotype is reduced in ap2c1 mkp1 mpk6 triple mutants, suggesting that the autoimmune-like response is due to MPK6 misregulation. We conclude that the evolutionarily distant MAPK phosphatases AP2C1 and MKP1 contribute crucially to the tight control of MPK6 activity, ensuring appropriately balanced stress signalling and suppression of autoimmune-like responses during plant growth and development.

Highlight

Double MAPK phosphatase mutant plants ap2c1 mkp1 exhibit constitutive, autoimmune-like stress responses, dependent on their substrate MAPK MPK6.
The 3D organisation of mitochondria in primate photoreceptors
Authors: Hayes Matthew J. , Tracey-White Dhani , Kam Jaimie Hoh , Powner Michael B. , Jeffery Glen
Published: June 2021

Vertebrate photoreceptors contain large numbers of closely-packed mitochondria which sustain the high metabolic demands of these cells. These mitochondria populations are dynamic and undergo fusion and fission events. This activity serves to maintain the population in a healthy state. In the event of mitochondrial damage, sub-domains, or indeed whole mitochondria, can be degraded and population homeostasis achieved. If this process is overwhelmed cell death may result. Death of photoreceptors contributes to loss of vision in aging individuals and is associated with many eye diseases. In this study we used serial block face scanning electron microscopy of adult (Macaca fascicularis) retinae to examine the 3D structure of mitochondria in rod and cone photoreceptors. Healthy-looking photoreceptors contain mitochondria with a range of shapes which are associated with different regions of the cell. In some photoreceptors we observe mitochondrial swelling and other changes we associate with stress or degeneration of the cell. In both rods and cones we identify elongated domains of mitochondria with densely-packed normal cristae associated with photoreceptor ciliary rootlet bundles. We observe mitochondrial fission and mitochondrion fragments localised to these domains. Swollen mitochondria with few intact cristae are located towards the periphery of the photoreceptor inner-segment in rods, whilst they are found throughout the cell in cones. Swollen mitochondria exhibit sites on the mitochondrial inner membrane which have undergone complex invagination resulting in membranous, electron-dense aggregates. Membrane contact occurs between the mitochondrion and the photoreceptor plasma membrane in the vicinity of these aggregates, and a series of subsequent membrane fusions results in expulsion of the mitochondrial aggregate from the photoreceptor. These events are primarily associated with rods, likely reflecting the ageing mechanism in primates where many rods die but cones do not. Possible consequences of this atypical mitochondrial degradation are discussed.
Identifying developing interneurons as a potential target for multiple genetic autism risk factors in human and rodent forebrain
Authors: Yang Yifei , Booker Sam A. , Clegg James M. , Urzainqui Idoia Quintana , Sumera Anna , Kozic Zrinko , Dando Owen , Lorenzo Sandra Martin , Herault Yann , Kind Peter C. , Price David J. , Pratt Thomas
Published: June 2021

Autism spectrum condition or ‘autism’ is associated with numerous monogenic and polygenic genetic risk factors including the polygenic 16p11.2 microdeletion. A central question is what neural cells are affected. To systematically investigate we analysed single cell transcriptomes from gestational week (GW) 8-26 human foetal prefrontal cortex and identified a subset of interneurons (INs) first appearing at GW23 with enriched expression of a disproportionately large fraction of risk factor transcripts. This suggests the hypothesis that these INs are disproportionately vulnerable to mutations causing autism. We investigated this in a rat model of the 16p11.2 microdeletion. We found no change in the numbers or position of either excitatory or inhibitory neurons in the somatosensory cortex or CA1 of 16p11.2+/- rats but found that CA1 Sst INs were hyperexcitable with an enlarged axon initial segment, which was not the case for CA1 pyramidal cells. This study prompts deeper investigation of IN development as a convergent target for autism genetic risk factors.
eggNOG-mapper v2: Functional Annotation, Orthology Assignments, and Domain Prediction at the Metagenomic Scale
Authors: Cantalapiedra Carlos P. , Hernández-Plaza Ana , Letunic Ivica , Bork Peer , Huerta-Cepas Jaime
Published: June 2021

Even though automated functional annotation of genes represents a fundamental step in most genomic and metagenomic workflows, it remains challenging at large scales. Here, we describe a major upgrade to eggNOG-mapper, a tool for functional annotation based on precomputed orthology assignments, now optimized for vast (meta)genomic data sets. Improvements in version 2 include a full update of both the genomes and functional databases to those from eggNOG v5, as well as several efficiency enhancements and new features. Most notably, eggNOG-mapper v2 now allows: (i) de novo gene prediction from raw contigs, (ii) built-in pairwise orthology prediction, (iii) fast protein domain discovery, and (iv) automated GFF decoration. eggNOG-mapper v2 is available as a standalone tool or as an online service at http://eggnog-mapper.embl.de.
X-Linked Histone H3K27 Demethylase Kdm6a Regulates Sexually Dimorphic Differentiation of Hypothalamic Neurons
Authors: Zapata Lucas E. Cabrera , Cisternas Carla D. , Sosa Camila , Arevalo Maria Angeles , Garcia-Segura Luis Miguel , Cambiasso María Julia
Published: June 2021

Several X-linked genes are involved in neuronal differentiation and may contribute to the generation of sex dimorphisms in brain. Previous results showed that XX hypothalamic neurons grow faster, have longer axons, and exhibit higher expression of the neuritogenic gene neurogenin 3 (Ngn3) than XY before perinatal masculinization. Here we evaluated the participation of candidate X-linked genes in the development of these sex differences, focusing mainly on Kdm6a, a gene encoding for an H3K27 demethylase with functions controlling gene expression genome-wide. We established hypothalamic neuronal cultures from wild-type or transgenic Four Core Genotypes mice, a model that allows evaluating the effect of sex chromosomes independently of gonadal type. X-linked genes Kdm6a, Eif2s3x and Ddx3x showed higher expression in XX compared to XY neurons, regardless of gonadal sex. Moreover, Kdm6a expression pattern with higher mRNA levels in XX than XY did not change with age at E14, P0, and P60 in hypothalamus or under 17β-estradiol treatment in culture. Kdm6a pharmacological blockade by GSK-J4 reduced the expression of neuritogenic genes Neurod1, Neurod2 and Cdk5r1 in both sexes equally, while a sex-specific effect was observed on Ngn3 levels, with a decrease in XX and an increase in XY neurons. Finally, both Kdm6a inhibition and its downregulation using siRNA reduced axonal length only in female neurons, abolishing the sex differences observed in control conditions. Altogether, these results point to Kdm6a as a key mediator of the higher axogenesis and Ngn3 expression observed in XX neurons before critical period of brain masculinization.
Taxonomic categories for commissioning and startup hot spot strategies
Authors: Mock Brant , O’Connor James
Published: June 2021

Purpose

The purpose of this study is to better understand distinct solution strategy types for common commissioning and startup problems (Hot Spots) in the construction of industrial facilities. The authors also sought to better understand which solution strategy types offer the best value for the effort required.

Design/methodology/approach

The authors used a method of qualitative coding of text-based data to identify themes, patterns and trends from a collection of 178 commissioning and startup (CSU) solution strategies for the CSU Hot Spots. Coding categories emerged after multiple iterations. The authors also mapped high-value, low-effort solution strategies across the categories. Chi-squared testing and analysis of proportion statistics help quantitatively justify this qualitative research.

Findings

The authors identified 12 distinct coding categories and showed that they follow a non-uniform distribution via statistical testing. Those strategy types which provide particularly good value for the effort required are identified (such as quality assurance and control strategies), as well as those strategy types that do not.

Research limitations/implications

Research is limited to CSU for the construction of industrial facilities. The findings are also limited to a subset of the most commonly problematic CSU activities. Many findings may be beneficial for heavy civil and commercial CSU as well.

Practical implications

Coding categories, definitions and descriptions provide a good overview of all 178 solution strategies for CSU project professionals. Implementing certain types of solutions or solution programs may allow CSU managers to prevent multiple Hot Spots from becoming problematic or to keep problems already occurring from becoming worse. Managers will also benefit from knowledge about which strategy types are more likely to give a higher value for lower effort.

Originality/value

Qualitative coding and analysis of solution strategies for common CSU problems have never been conducted so rigorously in any other CSU study. This method has yielded results distinct from other CSU studies which have used quantitative methods. Insights from findings have advanced the body of knowledge surrounding problem-solving in the commissioning and startup sub-discipline.
Incorporation of gradient-enhanced microplane damage model into isogeometric analysis
Authors: Han Jike , Yin Bo , Kaliske Michael , Tarada Kenjiro
Published: June 2021

Purpose

This study aims to develop a new analysis approach devised by incorporating a gradient-enhanced microplane damage model (GeMpDM) into isogeometric analysis (IGA), which shows computational stability and capability in accurately predicting crack propagations in structures with complex geometries.

Design/methodology/approach

For the non-local microplane damage modeling, the maximum modified von-Mises equivalent strain among all microplanes is regularized as a representative quantity. This characterization implies that only one additional governing equation is considered, which improves computational efficiency dramatically. By combined use of GeMpDM and IGA, quasi-static and dynamic numerical analyses are conducted to demonstrate the capability in predicting crack paths of complex geometries in comparison to FEM and experimental results.

Findings

The implicit scheme with the adopted damage model shows favorable numerical stability and the numerical results exhibit appropriate convergence characteristics concerning the mesh size. The damage evolution is successfully controlled by a tension-compression damage factor. Thanks to the advanced geometric design capability of IGA, the details of crack patterns can be predicted reliably, which are somewhat difficult to be acquired by FEM. Additionally, the damage distribution obtained in the dynamic analysis is in close agreement with experimental results.

Originality/value

The paper originally incorporates GeMpDM into IGA. Especially, only one non-local variable is considered besides the displacement field, which improves the computational efficiency and favorable convergence characteristics within the IGA framework. Also, enjoying the geometric design ability of IGA, the proposed analysis method is capable of accurately predicting crack paths reflecting the complex geometries of target structures.
Exploring the critical waste factors affecting construction projects
Authors: Bajjou Mohamed Saad , Chafi Anas
Published: June 2021

Purpose

Waste is typically encountered during the building's life cycle, from the design phase, through the construction phase, to modification and demolition. Most of these construction wastes are unnoticed or unattended by project managers, which lead to serious environmental problems. Effective waste reduction strategies will require a thorough and detailed understanding of the causes of construction waste. Hence, this paper aims to explore critical waste factors (CWFs) affecting the performance of construction projects.

Design/methodology/approach

An extensive literature review was carried out to determine these factors based on previous studies, from which a questionnaire was developed. Series of statistical analyses such as reliability analysis, Spearman Correlation, Kruskal–Wallis and factor analysis were performed on a total of 330 valid responses to identify latent factors responsible for wastes occurrence.

Findings

This study reveals 31 CWFs through evaluation of prior relevant studies carried out in several countries and then adjusted and validated through semistructured interviews. The significant differences in views within various groups of respondents with different organizational characteristics are highlighted. The results of factor analysis showed that there are six principal components extracted with 66.3% of variance explained (material-related factors; subcontractors and workers; planning, communication and coordination; people involvement and financial issues; people development strategies; and external factors).

Originality/value

This study differs from other studies in the literature by gathering all relevant waste factors including those related to nonphysical waste such as time, budget, workers and equipment. Furthermore, this paper will be of great interest to both practitioners and researchers since it brings various recommendations concerning the prevention/reduction of waste through lean construction for more sustainable construction projects.
New variational theory for coupled nonlinear fractal Schrödinger system
Authors: Wang KangLe
Published: June 2021

Purpose

The purpose of this paper is the coupled nonlinear fractal Schrödinger system is defined by using fractal derivative, and its variational principle is constructed by the fractal semi-inverse method. The approximate analytical solution of the coupled nonlinear fractal Schrödinger system is obtained by the fractal variational iteration transform method based on the proposed variational theory and fractal two-scales transform method. Finally, an example illustrates the proposed method is efficient to deal with complex nonlinear fractal systems.

Design/methodology/approach

The coupled nonlinear fractal Schrödinger system is described by using the fractal derivative, and its fractal variational principle is obtained by the fractal semi-inverse method. A novel approach is proposed to solve the fractal model based on the variational theory.

Findings

The fractal variational iteration transform method is an excellent method to solve the fractal differential equation system.

Originality/value

The author first presents the fractal variational iteration transform method to find the approximate analytical solution for fractal differential equation system. The example illustrates the accuracy and efficiency of the proposed approach.
Grain for Green Project in farmers’ minds: perceptions, aspirations and behaviours in eco-fragile region, Xinjiang, China
Authors: Duan Pei , Chen Shengdong , Zhang Heng , Zhang Fuchun
Published: June 2021

Purpose

This study aims to focus on the analysis of the internal mechanism of farmers’ ecological cognition and the behaviour of Grain for Green Project (GGP), and the further relationship between ecological cognition and ecological aspiration, proposing climate change strategies and management from the perspective of farmers.

Design/methodology/approach

Theory of planned behaviour and social exchange theory were used to construct a theoretical framework and an ecological cognition under the influence of external factors, the aspiration and the behaviour of GGP, using ecological fragile areas in Bazhou and Changji, Xinjiang of 618 peasant households’ survey data. The structural equation model and Heckman two-step model were applied to analyse the relationship between ecological cognition and ecological aspiration of farmers, the impact of peasant households’ ecological cognition and aspiration to the behaviour of GGP and the influence factors of GGP behaviour.

Findings

This research’s results show that the three characterizations of ecological cognitive variables, attitude towards the behaviour (AB), subjective norms (SN) and perceived behaviour control (PBC), have significant positive impact on farmers’ GGP ecological aspiration. The comprehensive impact path coefficients of ecological cognition are PBC (0.498) > SN (0.223) > AB (0.177). Also, income change is a moderating variable, which has a significant moderating effect on the influence of AB and SN on ecological aspiration. Further, farmers’ ecological cognition has an influence on the behaviour of GGP, and the change of farmers’ income has a significant positive effect on farmers’ choice of returning farmland to forests.

Practical implications

The ecological protection policy suggestions and countermeasures can be drawn from the research conclusions, adapted to China’s ecologically fragile regions and even similar regions in the world to response the climate change.

Originality/value

Combining the theory of planning behaviour and social exchange, this paper empirically analyses the path of farmers’ ecological cognition and ecological aspiration, as well as the influencing factors.
Developing IT-enabled performance monitoring system for green logistics: a case study
Authors: Chhabra Deepti , Singh Rajesh Kr , Kumar Vikas
Published: June 2021

Purpose

Logistics companies are compelled to improve their efficiency and the environmental performance by introducing the green concept in their operations. The main purpose of the paper is to have continuous monitoring and tracking of logistics operations to enhance the green performance.

Design/methodology/approach

This research uses a case study approach. It illustrates a monitoring system to digitize the logistics activities by sending real-time GPS data to the server and capture the surrounding pictures with the help of the internet of things (IoTs) based camera. Data generated through digitization is mathematically analyzed for ensuring a green logistic system. The alerts due to the halts, help in keeping a check on fuel consumption, carbon emissions and security of logistics. Performance indicators such as carbon emissions and the value of travel time saving (VTTS) are selected for the study.

Findings

The findings of the study show that the actual travel time and distances are higher than the estimated travel time and distances. It also reveals that actual travel routes with diversions involve a considerably higher amount of carbon emissions during all sample travels. The results indicate a considerable saving in terms of carbon emissions, time and cost savings by effective practices of Green Logistics in Monitoring system (MSGL). These findings can help the top management of logistics companies in formulating effective strategies for technology applications in logistic operations to ensure green performance.

Research limitations/implications

The study has been carried out under certain set of conditions, which may vary depending upon the organizations. Also certain more environmental dimensions for performance monitoring can be used as a future scope of study. Further studies also need to be carried out to widen the scope of the MSGL model at a global level rather than only at local level.

Originality/value

Any organization which deploys transportation as part of their activity can use this MSGL model and then do the mathematical analysis to reduce the CO2 emissions, reduce the time and extra cost. The value of this study lies in the fact that government is trying different methods and models to reduce pollution. This MSGL should be made compulsory by the government as a part of their policies for environment of the country.
E-tailers adaptation during early stages of “social distancing causing crises”: an exploratory study
Authors: Halan Deepak
Published: June 2021

Purpose

This paper studies the impact of social distancing causing crises (SDCC) such as pandemics in its early stages on e-tailers demand and supply side operations and provides a conceptual framework for adaptation.

Design/methodology/approach

A grounded theory-based approach has been used, wherein journal papers and news articles are the key data sources. Standard qualitative methodology, including open, axial and selective coding has been followed.

Findings

The study provides second order themes derived from first-order categories, the theoretical dimensions and their interrelationships on how e-tailers need to adapt to variations in online buying behaviour, manage manpower shortage and daily necessities inventory shortage, during SDCC. Panic buying emerges as a key disrupting factor as it has multiple repercussions on demand and supply side operations of e-tailers.

Research limitations/implications

Exploratory qualitative research such as this is helpful in early development of a research stream and paves the way for future quantitative studies.

Practical implications

This study makes a valuable contribution on e-tailers adaptation to SDCC with significant managerial implications. There are social, economic and policy implications too. For academicians, this study provides a conceptual framework and serves as a springboard for future research.

Originality/value

The study is unique as perhaps it is one of the first to study e-tailers adaptation to SDCC. It contributes to a body of the literature which is currently scarce but expected to grow exponentially in the coming years.
Fiscal reform: a computable general equilibrium (CGE) analysis for the Kingdom of Saudi Arabia
Authors: Roos Elizabeth Louisa , Adams Philip David
Published: June 2021

Purpose

This paper aims to provide a quantitative assessment of the broad economic effects of tax policy reform in the Kingdom of Saudi Arabia (KSA).

Design/methodology/approach

Using a dynamic computable general equilibrium (CGE) model of the KSA, three simulations are run. The first simulation is the baseline simulation, which generates growth paths of the Saudi economy in the absence of tax reform. In developing the baseline simulation, this study incorporates forecasts from the International Monetary Fund. The remaining simulations are policy simulations. A policy simulation deviates from the baseline simulation in response to a policy change. In the first policy simulation, this study introduces a value-added tax (VAT) that generates SAR 35bn. This study assumes budget neutrality with the additional tax revenue transferred to households via a lump sum payment. In the second policy simulation, this study introduces a corporate income tax that generates SAR 35bn. This study then calculates and compares the distortion these taxes introduce into the economy.

Findings

This study finds that although the introduction of new taxes increases government tax revenue, markets are distorted lowering efficiency and production. An introduction of VAT increases the cost of consumption relative to the cost of production. As a consequence, the real cost of labour increases lowering employment in the short run. Employment moves to the baseline, as wages adjust capital and real gross domestic product (GDP) is below base throughout the simulation period. The second simulation is an increase in the corporate tax rate with lowers the post-tax rates of return investors receive. This simulation shows that the negative impact on investment, capital and GDP is larger with the introduction of a corporate tax than with the VAT.

Research limitations/implications

Literature focusing on tax policy reform in the Gulf Cooperation Council and, specifically, Saudi Arabia is limited. This paper contributes to the literature by focusing on the following: understanding the impact and mechanisms through which changes in taxation impact the economy more generally; understanding the potential harm caused to allocative efficiency and production due to taxes; and ways in which fiscal reform might complement other reforms such as efforts to diversify the economy, labour market and energy price reforms. This improves the information base available to policymakers charged with designing an optimal tax system that meets all future requirements of a country such as the KSA.

Originality/value

The authors developed and applied a CGE model for the KSA to analyse the impact of VAT and corporate tax on the Saudi economy. To the best of the authors’ knowledge, there are no recent CGE models for Saudi Arabia that have been used for tax policy or quantifying the potential harm to the economy when new taxes are introduced.
Measuring burdening effect of Shariah knowledge on sales performance; does work experience matter? A multi-group analysis in the Islamic finance industry
Authors: Shamsudheen Shinaj Valangattil , Mahomed Ziyaad
Published: June 2021

Purpose

This study aims to examine the burdening effect of Shariah knowledge on the sales performance of the salesforce at Islamic financial institutions (IFIs) with special reference to addressing the heterogeneous effects of work experience.

Design/methodology/approach

A total of 335 samples were collected from the sales professionals of IFIs in Malaysia using a purposive sampling technique and the empirical analysis was conducted with the measures of model fit and bootstrapping technique using partial least square structural equation modeling and multi-group analysis.

Findings

Empirical results indicate that the burdening effect of Shariah knowledge is evident among salesforce and the magnitude of the impact remains consistent across the groups of salesforces with different levels of work experience.

Practical implications

Findings suggest respective authorities of IFIs intensify capacity building for their salesforce particularly in the area of Shariah knowledge and nature of underlying Islamic contracts used in the financial products. An insignificant heterogeneous effect of work experience suggests respective authorities that the actions and policy formulations are equally important among the entire salesforce regardless of the number of years of job tenure each salesforce holds.

Originality/value

As customer awareness and knowledge may be influenced by the information transferred via the IFI employees (especially salesforce in IFIs), any information overload (i.e. additional requirement of Shariah knowledge/features) on the IFI employees may, therefore, negatively influence customer patronage and reduce IFI market share. However, the increased information expectation (i.e. Shariah knowledge/features) on IFI employees and its impact on market share along with the heterogeneous effect of work experience has not been documented before. If a burdening effect of Shariah knowledge is identified, this may be a formidable reason for the slowing growth of Islamic finance.
The quadruple and quintuple helix in innovation environments (incubators and science and technology parks)
Authors: Mineiro Andrea Ap da Costa , Assis de Souza Thais , Carvalho de Castro Cleber
Published: June 2021

Purpose

The purpose of this paper is to investigate the literature on the representation of the quadruple and quintuple helix (QQH) in innovation environments such as incubators and science and technology parks (STPs).

Design/methodology/approach

The authors used the integrative review as a methodological approach and systematized studies regarding the main research objectives; theoretical approaches; methodology and study object; QQH representation, by identifying actor, performance and main results; and additional contributions to the QQH model.

Findings

As a result, the authors noticed a lack of standardization on the representation of the quadruple helix, but the example of associations and community centers as representatives of the civil society. The quintuple helix does not have an actor that represents the environment, but STPs foster sustainable actions, encourage the generation of green companies and stimulate sustainable practices among established companies.

Originality/value

Based on changes in the economic and social scenarios, new theoretical approaches emerge to explain the innovation process, such as the QQH. Incubators and STPs are favorable settings for interactions, according to the new models; however, there is a lack of studies addressing this topic in such environments. Hence, this study contributes to understanding the existence and performance of QQH, by showing how these new helices were identified, in addition to advancing the subject in innovation environments such as incubators and STPs.