bluuebunny/crossref_metadata_2025 huggingface dataset:
Dimension reduction and denoising of single-cell RNA sequencing data in the presence of observed confounding variables
Authors: Huang Mo , Zhang Zhaojun , Zhang Nancy R.
Published: August 2020

Confounding variation, such as batch effects, are a pervasive issue in single-cell RNA sequencing experiments. While methods exist for aligning cells across batches, it is yet unclear how to correct for other types of confounding variation which may be observed at the subject level, such as age and sex, and at the cell level, such as library size and other measures of cell quality. On the specific problem of batch alignment, many questions still persist despite recent advances: Existing methods can effectively align batches in low-dimensional representations of cells, yet their effectiveness in aligning the original gene expression matrices is unclear. Nor is it clear how batch correction can be performed alongside data denoising, the former treating technical biases due to experimental stratification while the latter treating technical variation due inherently to the random sampling that occurs during library construction and sequencing. Here, we propose SAVERCAT, a method for dimension reduction and denoising of single-cell gene expression data that can flexibly adjust for arbitrary observed covariates. We benchmark SAVERCAT against existing single-cell batch correction methods and show that while it matches the best of the field in low-dimensional cell alignment, it significantly improves upon existing methods on the task of batch correction in the high-dimensional expression matrix. We also demonstrate the ability of SAVERCAT to effectively integrate batch correction and denoising through a data down-sampling experiment. Finally, we apply SAVERCAT to a single cell study of Alzheimer’s disease where batch is confounded with the contrast of interest, and demonstrate how adjusting for covariates other than batch allows for more interpretable analysis.
Merkel cell polyomavirus in Merkel cell carcinoma: Integration sites and involvement of the KMT2D tumor suppressor gene
Authors: Arora Reety , Choi Jae Eun , Harms Paul W. , Chandrani Pratik
Published: August 2020

Merkel cell carcinoma (MCC) is an uncommon, lethal cancer of the skin caused by either Merkel cell polyomavirus (MCV) or UV-linked mutations. MCV is found integrated into MCC tumor genomes, accompanied by truncation mutations that render the MCV large T antigen replication incompetent. We used the open access HPV Detector/ Cancervirus Detector tool to determine the MCV integration sites in whole exome sequencing data from 5 MCC cases, thereby adding to the limited published MCV integration site junction data. We also systematically reviewed published data on integration for MCV in the human genome, presenting a collation of 123 MCC cases and their linked chromosomal sites. We confirm that there are no highly recurrent specific sites of integration. We found that, chromosome 5 is the chromosome most frequently involved by MCV integration and that integration sites are significantly enriched for genes with binding sites for oncogenic transcription factors such as LEF1 and ZEB1, suggesting the possibility of increased open chromatin in these gene sets. Additionally, in one case we found integration involving the tumor suppressor geneKMT2Dfor the first time, adding to previous reports of rare MCV integration into host tumor suppressor genes in MCC.
An organotypicin vitromodel of matured blood vessels
Authors: Lee Jaehyun , Lee Esak
Published: August 2020

Angiogenesis is a physiological process in which brand-new blood vessels are formed from pre-existing blood vessels. The angiogenic processes are achieved by multiple steps, including angiogenic vascular sprouting, lumen formation, mural cell (e.g., smooth muscle cells) recruitment, and vessel stabilization by the mural cell coverage of the neovessels. Especially, mural cell recruitment to and coverage of the newly formed endothelium is a fundamental process to provide fully matured, functional blood vessels. Although investigation of the mural cell interactions with endothelial cells is crucial not only for better understanding of vascular physiology, but also for treating numerous vascular diseases, there has been a lack of three-dimensional (3D)in vitromodels that recapitulate spontaneous processes of the vascular maturation. In this study, we describe an organotypicin vitromodel that represents multi-step, spontaneous vascular maturation processes, which includes angiogenic vessel sprouting, smooth muscle cell (SMC) recruitment, and the SMC coverage of the neovessels. Using the system, we could spatiotemporally control vessel sprouting and vessel stabilization/maturation; and revealed an optimal condition that could reconstitute SMC-covered, matured blood vessels in 3Din vitro. We may provide a new platform for future mechanism studies of vascular interactions to mural cells and vessel maturation; and for pre-clinical screening and validation of therapeutic agent candidates for treating vascular diseases.
Oxygen-independent chemogenetic protein tags for live-cell fluorescence microscopy
Authors: Iyer Aditya , Baranov Maxim , Foster Alexander J , Chordia Shreyans , Roelfes Gerard , van den Bogaart Geert , Poolman Bert
Published: August 2020

Fluorescent proteins enable targeted visualization of biomolecules in living cells, but their maturation is oxygen-dependent and they are susceptible to aggregation and/or suffer from poor photophysical properties. Organic fluorophores are oxygen-independent with superior photophysical properties, but targeting biomolecules in vivo is challenging. Here, we introduce two oxygen-independent chemogenetic protein (OICP) tags that impart fluorogenicity and fluorescence lifetime enhancement to bound organic dyes. We present a photo- and physicochemical characterization of thirty fluorophores interacting with two OICPs and conclude that aromatic planar structures bind with high specificity to the hydrophobic pockets of the proteins. The binding specificity of the tags and the superior photophysical properties of organic fluorophores enable microscopy of living bacterial and eukaryotic cells. The exchange of photobleached dye for unbleached fluorophore enables prolonged live-cell imaging. Our protein tags provide a general tool for investigating (sub)cellular protein localization and dynamics, protein-protein interactions, and microscopy applications under strictly oxygen-free conditions.
De novo design of picomolar SARS-CoV-2 miniprotein inhibitors
Authors: Cao Longxing , Goreshnik Inna , Coventry Brian , Case James Brett , Miller Lauren , Kozodoy Lisa , Chen Rita E. , Carter Lauren , Walls Lexi , Park Young-Jun , Stewart Lance , Diamond Michael , Veesler David , Baker David
Published: August 2020

We used two approaches to design proteins with shape and chemical complementarity to the receptor binding domain (RBD) of SARS-CoV-2 Spike protein near the binding site for the human ACE2 receptor. Scaffolds were built around an ACE2 helix that interacts with the RBD, or de novo designed scaffolds were docked against the RBD to identify new binding modes. In both cases, designed sequences were optimized first in silico and then experimentally for target binding, folding and stability. Nine designs bound the RBD with affinities ranging from 100pM to 10nM, and blocked bona fide SARS-CoV-2 infection of Vero E6 cells with IC50values ranging from 35 pM to 35 nM; the most potent of these — 56 and 64 residue hyperstable proteins made using the second approach — are roughly six times more potent on a per mass basis (IC50~ 0.23 ng/ml) than the best monoclonal antibodies reported thus far. Cryo-electron microscopy structures of the SARS-CoV-2 spike ectodomain trimer in complex with the two most potent minibinders show that the structures of the designs and their binding interactions with the RBD are nearly identical to the computational models, and that all three RBDs in a single Spike protein can be engaged simultaneously. These hyperstable minibinders provide promising starting points for new SARS-CoV-2 therapeutics, and illustrate the power of computational protein design for rapidly generating potential therapeutic candidates against pandemic threats.
Predation byBdellovibrio bacteriovorustransforms the landscape and community assembly of bacterial biofilms
Authors: Wucher Benjamin R. , Elsayed Mennat , Kadouri Daniel E. , Nadell Carey D.
Published: August 2020

The predatory bacteriumBdellovibrio bacteriovorusfollows a life cycle in which it attaches to the exterior of a Gram-negative prey cell, enters the periplasm, and harvests resources to replicate before lysing the host to find new prey. Predatory bacteria such as this are common in many natural environments, as are groups of matrix-bound clusters of prey cells, termed biofilms. Despite the ubiquity of both predatory bacteria and biofilm-dwelling prey, the interaction betweenB. bacteriovorusand prey cells inside biofilms has received little attention and has not yet been studied at the micrometer scale. Filling this knowledge is critical to understanding the nature of predator-prey interaction in nature. Here we show thatB. bacteriovorusis able to prey upon biofilms of the pathogenVibrio cholerae, but only up until a critical maturation threshold past which the prey biofilms are protected from their predators. We determine the contribution of matrix secretion and cell-cell packing of the prey biofilm toward this protection mechanism. Our results demonstrate thatB. bacteriovoruspredation in the context of this protection threshold fundamentally transforms the sub-millimeter scale landscape of biofilm growth, as well as the process of community assembly as new potential biofilm residents enter the system.
Allele Frequency Mismatches and Apparent Mismappings in UK Biobank SNP Data
Authors: Kunert-Graf James , Sakhanenko Nikita , Galas David
Published: August 2020

We report here some anomalies discovered in the minor allele frequencies (MAFs) and some likely mismappings found in our analyses of UK Biobank dataset (UKB) and several other databases. We compared the MAFs present in the UKB to those measured in two other UK studies, ALSPAC and TwinsUK, and found a large set of SNPs for which the UKB MAFs are inconsistent. Additionally, even after accounting for population structure effects and other possible causes of spurious correlations, we found many SNPs that appear to be in interchromosomal linkage. Analyzing these interchromosomal linkages carefully, we found that they are all associated with identical sequences on different chromosomes, implying that these SNPs are simply mismapped. Some (but certainly not all) of the MAF disagreements appear to be the result of these mismappings. Our results, including lists of SNPs with inconsistent MAFs and/or apparent interchromosomal linkage, are freely available to download at:http://kunertgraf.com/data/biobank.html
An unexpected bifurcation in the Pointed transcriptional effector network contributes specificity and robustness to retinal cell fate acquisition
Authors: Wu Chudong , Lachance Jean-François Boisclair , Ludwig Michael Z , Rebay Ilaria
Published: August 2020

Spatiotemporally specific and robust cell fate transitions are fundamental to the development of appropriately patterned tissues. In theDrosophilaretina, receptor tyrosine kinase / mitogen activated protein kinase (MAPK) signaling acts through the transcriptional effector Pointed (Pnt) to direct two distinct rounds of photoreceptor specification. A relay mechanism between two Pnt isoforms, a MAPK responsive form PntP2 and a constitutively active form PntP1, initiates and sustains the transcriptional response. Here, we report an unexpected bifurcation in the Pnt effector network. We show that PntP2 works redundantly with a closely related but previously uncharacterized isoform, PntP3, to activatepntP1during specification of first round photoreceptors. Intrinsic activity differences between PntP2 and PntP3, combined with positive and negative transcriptional auto- and cross-regulation, buffer first-round fates against conditions of low signaling. In contrast, in a mechanism that may be adaptive to the stronger signaling environment used to specify second round fates, PntP2 uniquely activatespntP1. We propose that differences in expression patterns, transcriptional activities and regulatory interactions between Pnt isoforms together facilitate context-appropriate cell fate specification in different signaling environments.
Rates of gene conversions betweenEscherichia coliribosomal operons
Authors: Gifford Isaac , Dasgupta Aurko , Barrick Jeffrey E.
Published: August 2020

Due to their universal presence and high sequence conservation, rRNA sequences are used widely in phylogenetics for inferring evolutionary relationships between microbes and in metagenomics for analyzing the composition of microbial communities. Most microbial genomes encode multiple copies of ribosomal RNA (rRNA) genes to supply cells with sufficient capacity for protein synthesis. These copies typically undergo concerted evolution that keeps their sequences identical, or nearly so, due to gene conversion, a type of intragenomic recombination that changes one copy of a homologous sequence to exactly match another. Widely varying rates of rRNA gene conversion have previously been estimated by comparative genomics methods and using genetic reporter assays. To more directly measure rates of rRNA intragenomic recombination, we sequenced the sevenEscherichia colirRNA operons in 15 lineages of cells that were evolved for ~13,750 generations with frequent single-cell bottlenecks that reduce the effects of selection. We identified 34 gene conversion events and estimate an overall rate of intragenomic recombination events between rRNA copies of 3.2 × 10−4per generation or 5.3 × 10−5per potential donor sequence. This rate varied only slightly from random expectations between different portions of the rRNA genes and between rRNA operons located at different locations in the genome. This accurate estimate of the rate of rRNA gene conversions fills a gap in our quantitative understanding of how ribosomal sequences and other multicopy elements diversify and homogenize during microbial genome evolution.
Quantification of cell behaviours and computational modelling show that cell directional behaviours drive zebrafish pectoral fin morphogenesis
Authors: Dokmegang Joel , Nguyen Hanh , Kardash Elena , Savy Thierry , Cavaliere Matteo , Peyriéras Nadine , Doursat René
Published: August 2020

Motivation

Understanding the mechanisms by which the zebrafish pectoral fin develops is expected to produce insights on how vertebrate limbs grow from a 2D cell layer to a 3D structure. Two mechanisms have been proposed to drive limb morphogenesis in tetrapods: a growth-based morphogenesis with a higher proliferation rate at the distal tip of the limb bud than at the proximal side, and directed cell behaviors that include elongation, division and migration in a nonrandom manner. Based on quantitative experimental biological data at the level of individual cells in the whole developing organ, we test the conditions for the dynamics of pectoral fin early morphogenesis.

Results

We found that during the development of the zebrafish pectoral fin, cells have a preferential elongation axis that gradually aligns along the proximodistal axis (PD) of the organ. Based on these quantitative observations, we build a center-based cell model enhanced with a polarity term and cell proliferation to simulate fin growth. Our simulations resulted in 3D fins similar in shape to the observed ones, suggesting that the existence of a preferential axis of cell polarization is essential to drive fin morphogenesis in zebrafish, as observed in the development of limbs in the mouse, but distal tip-based expansion is not.

Availability

Upon publication, biological data will be available athttp://bioemergences.eu/modelingFin, and code source athttps://github.com/guijoe/MaSoFin.

Contact

joel.dokmegang-kassap@stu.mmu.ac.uk,nadine.peyrieras@cnrs.frorrene.doursat@iscpif.fr

Supplementary information

Supplementary data are included in this manuscript.
Multi-scale modeling of macrophage – T cell interactions within the tumor microenvironment and impacts of macrophage-based immunotherapies
Authors: Cess Colin G. , Finley Stacey D.
Published: August 2020

Within the tumor microenvironment, macrophages exist in an immunosuppressive state, preventing T cells from eliminating the tumor. Due to this, research is focusing on immunotherapies that specifically target macrophages in order to reduce their immunosuppressive capabilities and promote T cell function. In this study, we develop an agent-based model consisting of the interactions between macrophages, T cells, and tumor cells to determine how the immune response changes due to three macrophage-based immunotherapeutic strategies: macrophage depletion, recruitment inhibition, and macrophage reeducation. We find that reeducation, which converts the macrophages into an immune promoting phenotype, is the most effective strategy and that the macrophage recruitment rate and tumor proliferation rate (tumor-specific properties) have large impacts on therapy efficacy. We also employ a novel method of using a neural network to reduce the computational complexity of an intracellular signaling mechanistic model.
SARS-CoV-2 antigens expressed in plants detect antibody responses in COVID-19 patients
Authors: Makatsa Mohau S. , Tincho Marius B. , Wendoh Jerome M. , Ismail Sherazaan D. , Nesamari Rofhiwa , Pera Francisco , Beer Scott de , David Anura , Jugwanth Sarika , Gededzha Maemu P. , Mampeule Nakampe , Sanne Ian , Stevens Wendy , Scott Lesley , Blackburn Jonathan , Mayne Elizabeth S. , Keeton Roanne S. , Burgers Wendy A.
Published: August 2020

Background

The SARS-CoV-2 pandemic has swept the world and poses a significant global threat to lives and livelihoods, with over 16 million confirmed cases and at least 650 000 deaths from COVID-19 in the first 7 months of the pandemic. Developing tools to measure seroprevalence and understand protective immunity to SARS-CoV-2 is a priority. We aimed to develop a serological assay using plant-derived recombinant viral proteins, which represent important tools in less-resourced settings.

Methods

We established an indirect enzyme-linked immunosorbent assay (ELISA) using the S1 and receptor-binding domain (RBD) portions of the spike protein from SARS-CoV-2, expressed in Nicotiana benthamiana. We measured antibody responses in sera from South African patients (n=77) who had tested positive by PCR for SARS-CoV-2. Samples were taken a median of six weeks after the diagnosis, and the majority of participants had mild and moderate COVID-19 disease. In addition, we tested the reactivity of pre-pandemic plasma (n=58) and compared the performance of our in-house ELISA with a commercial assay. We also determined whether our assay could detect SARS-CoV-2-specific IgG and IgA in saliva.

Results

We demonstrate that SARS-CoV-2-specific immunoglobulins are readily detectable using recombinant plant-derived viral proteins, in patients who tested positive for SARS-CoV-2 by PCR. Reactivity to S1 and RBD was detected in 51 (66%) and 48 (62%) of participants, respectively. Notably, we detected 100% of samples identified as having S1-specific antibodies by a validated, high sensitivity commercial ELISA, and OD values were strongly and significantly correlated between the two assays. For the pre-pandemic plasma, 1/58 (1.7%) of samples were positive, indicating a high specificity for SARS-CoV-2 in our ELISA. SARS-CoV-2-specific IgG correlated significantly with IgA and IgM responses. Endpoint titers of S1- and RBD-specific immunoglobulins ranged from 1:50 to 1:3200. S1-specific IgG and IgA were found in saliva samples from convalescent volunteers.

Conclusions

We demonstrate that recombinant SARS-CoV-2 proteins produced in plants enable robust detection of SARS-CoV-2 humoral responses. This assay can be used for seroepidemiological studies and to measure the strength and durability of antibody responses to SARS-CoV-2 in infected patients in our setting.
Mapping of internal audit research: a post-Enron structured literature review
Authors: Kotb Amr , Elbardan Hany , Halabi Hussein
Published: August 2020

Purpose

This paper reviews the field of internal auditing (IA) post-Enron to develop insights into how IA research has developed, offer a critique of the research to date and identify ways that future research can help to advance IA.

Design/methodology/approach

A structured literature review (SLR) was used to analyse 471 papers from 64 journals published between 2005 and 2018 based on a number of criteria, namely author, journal type, journal location, year, theme, theory, nature of research, research setting, regional focus, method and citations.

Findings

The IA literature has not significantly contributed to knowledge of the internal audit function (IAF), and one still knows relatively little about the factors that contribute to making the impact of IA practice effective and measurable. The IA literature is US-dominated (authors and journals), focussed on the American context (publicly listed companies), reliant on positivist analyses and largely makes no explicit reference to theory. Central regions (emerging economies) and key organisational settings (private SMEs and not-for-profit organisations) are largely absent in prior IA research. This paper evaluates and identifies avenues through which future research can help to advance IA in order to address emerging challenges in the field.

Originality/value

This is the first comprehensive review to analyse IA research in the post-Enron period (2005–2018). The findings are relevant to researchers who are looking for appropriate research outlets and emerging scholars who wish to identify their own research directions.
Regulating Macao's casino gaming: two decades of development and prospects
Authors: Wang Changbin
Published: August 2020

Purpose

The purpose of this paper is to review Macao's gaming regulation from 2001, when competition was introduced into the gaming market, to the present and discuss the potential methods to improve the regulatory system in the future.

Design/methodology/approach

This paper adopts the qualitative approach, investigating and studying the contents, changes and enforcement of the gaming legislations.

Findings

The gaming regulation in Macao has made great progress in the past two decades. Before 2001, the gaming market was monopolized, and the gaming regulation was merely a concession system. Law No. 16/2001, together with the other laws and regulations promulgated later, established a regulatory framework containing rules of suitability check, casino entry, competition, internal control, gaming promotion, credit gaming and antimoney laundering. The implementation of the rules has also drawn attention of the international community.

Originality/value

This paper reviews the gaming regulation in Macao in all its major aspects for the first time and argues that a framework of gaming regulation has been established in Macao although it needs to be improved.
How to increase social capital of organizations: identifying the role of informal learning behaviors
Authors: Joseph Nidheesh , Totawar Abhishek
Published: August 2020

Purpose

The purpose of this paper is to highlight the role of informal learning behaviors in increasing the social capital of organizations. The paper provides a brief overview of social capital and informal learning and proposes to interlink them for increasing knowledge capability of organizations.

Design/methodology/approach

Drawing on a review of social capital theory and informal learning behaviors, this article presents a conceptual approach for practitioners to deploy informal learning behaviors to increase social capital and subsequently, the knowledge capability of their organizations.

Findings

With the fast-changing global business scenario and limited availability of capital to invest in formal training behaviors, organizations continue to face difficulties in increasing their knowledge capability. This article suggests a simple, cost-effective and easy-to-deploy method of employing informal learning behaviors to build and sustain social capital and through it the knowledge capabilities of organizations.

Originality/value

There is currently limited research into the applicability of using informal learning behaviors in the field of social capital and knowledge capability building.
Quali health: creating access to quality healthcare for South Africa’s excluded majority
Authors: Saville Adrian David , Powell Philip , Ismail-Saville Tashmia , Mthombeni Morris
Published: August 2020

Learning outcomes

For discussion of social entrepreneurship in middle-income economies, emerging markets generally and Africa, specifically, Quali Health presents interesting questions about entrepreneurial funding, scaling and the interplay between social entrepreneurial activities and the informal sector.

Case overview/synopsis

South Africa’s primary health outcomes do not correspond to the country’s spending on public health, with South Africa ranking among the worst globally in the incidence of tuberculosis, HIV prevalence, infant mortality and life expectancy. In part, this poor outcome can be explained by high inequality in access to healthcare, which reflects South Africa’s grossly skewed income and wealth distributions, with the bulk of the country’s population reliant upon an underfunded, inefficient and poorly managed public health system. This substandard service for the working poor in South Africa’s townships with high population densities offered a profitable entrepreneurial opportunity to provide affordable and effective primary care with vast gains in quality and outcomes improved dignity for patients. After receiving her MBA, physician and entrepreneur Dr Nthabiseng Legoete self-funded the launch of Quali Health in 2017. The business model set out to disrupt healthcare delivery for South Africa’s poorest citizens. Drawing patients from the working poor in Diepsloot, Quali Health’s inaugural site was cash flow positive within five months when the facility hit only 30% of installed service capacity. With quick success, Dr Legoete faced the strategic question of how fast to scale and finance the expansion. She also considered a new micro-insurance product for her clientele.

Complexity academic level

For discussion of social entrepreneurship in middle-income economies, emerging markets generally and Africa, specifically, Quali Health presents interesting questions about entrepreneurial funding, scaling and the interplay between social entrepreneurial activities and the informal sector.

Supplementary materials

Teaching notes are available for educators only.

Subject code

CSS: 3 Entrepreneurship.
How effective are social engineering interventions? A meta-analysis
Authors: Bullee Jan-Willem , Junger Marianne
Published: August 2020

Purpose

Social engineering is a prominent aspect of online crime. Various interventions have been developed to reduce the success of this type of attacks. This paper aims to investigate if interventions can help to decrease the vulnerability to social engineering attacks. If they help, the authors investigate which forms of interventions and specific elements constitute success.

Design/methodology/approach

The authors selected studies which had an experimental design and rigorously tested at least one intervention that aimed to reduce the vulnerability to social engineering. The studies were primarily identified from querying the Scopus database. The authors identified 19 studies which lead to the identification of 37 effect sizes, based on a total sample of N = 23,146 subjects. The available training, intervention materials and effect sizes were analysed. The authors collected information on the context of the intervention, the characteristics of the intervention and the characteristics of the research methodology. All analyses were performed using random-effects models, and heterogeneity was quantified.

Findings

The authors find substantial differences in effect size for the different interventions. Some interventions are highly effective; others have no effect at all. Highly intensive interventions are more effective than those that are low on intensity. Furthermore, interventions with a narrow focus are more effective than those with a broad focus.

Practical implications

The results of this study show differences in effect for different elements of interventions. This allows practitioners to review their awareness campaigns and tailor them to increase their success.

Originality/value

The authors believe that this is the first study that compares the impact of social engineering interventions systematically.
Cooperative practices and non-financial performance of savings and credit cooperative societies
Authors: Kyazze Lawrence Musiitwa , Nsereko Isa , Nkote Isaac
Published: August 2020

Purpose

The purpose of this paper is to examine the relationship between cooperative practices of accountability, cooperative ownership, advanced communication and non-financial performance in savings and credit cooperative societies.

Design/methodology/approach

The study uses a cross-sectional research design and adopted a mixed methodological approach were hypotheses were statistically tested using structural equation modeling based on survey data (n= 220) and narratives from qualitative findings supported the quantitative findings from savings and credit cooperative societies.

Findings

The findings reveal that cooperative practices of accountability, cooperative ownership and advanced communication are significantly and positively associated with non-financial performance of savings and credit cooperative societies.

Originality/value

This study provides empirical evidence on the relationship between cooperative practices of accountability, cooperative ownership and advanced communication and non-financial performance in savings and credit cooperative societies in emerging economies like Uganda. To the best of the authors’ knowledge, there is limited or no study that has used the construct of agency theory in explaining the relationship between cooperative practices and non-financial performance in savings and credit cooperative societies.
Study on welded joints’ stress state grade of aluminum alloy EMU body
Authors: Xie Suming , Li Chunyun , Wang Jian , Li Wanpeng , Niu Chunliang
Published: August 2020

Purpose

Based on the DVS1608-2011 and IIW-2008 and BS EN15085-3 standards, the stress state grade of welded joints of aluminum alloy EMU (Electric Multiple Units) body was studied.

Design/methodology/approach

First, the calculation methods of the stress state grade of aluminum alloy welded joints analyzed by DVS1608-2011 and IIW-2008 standards were studied, and the two methods were programmed by the APDL language of ANSYS. Then, the finite element model of aluminum alloy EMU body was established; the static strength calculation result of the body was compared with the test result, and the error is basically within 10%. Finally, under the acceleration fatigue load provided by BS EN12663 standard, the fatigue analysis was carried out on the welded joint of the vehicle body, and the stress state of the welded joint of the vehicle body was studied according to IIW-2008 and DVS1608 standards, respectively.

Findings

The results show that the assessment method based on IIW-2008 standard is more rigorous, and the maximum stress factor of the longitudinal weld between the side beam and the side wall is 0.811; the position occurs in the area where the longitudinal weld of the side beam and the side wall is close to the lower door angle.

Originality/value

The stress state is medium, and the rest of the weld stress states are low.
Addressing the contamination issue in collaborative consumption of fashion: does ownership type of shared goods matter?
Authors: Kim Naeun Lauren , Jin Byoungho Ellie
Published: August 2020

Purpose

One of the major concerns in the emerging phenomenon of collaborative consumption (CC) is the issue of contamination (i.e. feeling “grossed out” when sharing items with others). Guided by the law of contagion and the consumer contamination effect theory, this research investigated the ways in which companies can manipulate in order to reduce the negative contamination when renting or purchasing used fashion items from others. Specifically, this research examines this issue of contamination through the ownership type of the shared goods (e.g. corporate-ownership or B2C exchange, and consumer-ownership or C2C exchange) and its effect on consumers' CC intentions in two distinct sharing contexts (i.e. rental and secondhand purchase).

Design/methodology/approach

A total of 181 American female consumers were assigned to an experimental CC scenario, and their rental/secondhand purchase intentions were compared through ANCOVA analysis.

Findings

In both rental and secondhand purchase contexts, consumers displayed greater intentions to shop in B2C setting (i.e. corporate-ownership) with no direct contact with the previous owner, than in C2C setting (i.e. consumer-ownership) with a greater association with the previous owner and the shared items. Such inclination was more prevalent when purchasing a shirt than a handbag, suggesting that consumers feel more grossed out when there is greater physical contact with the shared item.

Originality/value

The findings of the study suggest a possible solution to alleviate the contamination effect, and the discovery of the degree of contact as a moderator provides new insight into contamination research.
Knowledge management capability, environmental dynamism and innovation strategy in Malaysian firms
Authors: Taghizadeh Seyedeh Khadijeh , Karini Artan , Nadarajah Gunalan , Nikbin Davoud
Published: August 2020

Purpose

The objectives of this study is first to assess the effect of organizational antecedents on knowledge management capability and its effect on innovation strategy through the moderating effect of environmental dynamism.

Design/methodology/approach

The data were collected from SMEs in central region of Malaysia through a cross-sectional survey of 202 owners and analyzed through structural equation modeling using SmartPLS software.

Findings

The results show that while formal structure, selection policies, incentives and training and development policies have positive affect on knowledge management capability, there is no effect of innovation culture on knowledge management capability. Knowledge management capability has a positive and significant effect on innovation strategy. Interestingly, the findings show that environmental dynamism strengthens the positive effect of knowledge management capability on innovation strategy.

Practical implications

The findings of this study emphasize on the potential of collaboration among people for creating effective knowledge sharing in organizations and modalities in order to successfully design a collaborative knowledge-based work environment.

Originality/value

The model links organizational antecedents with knowledge management capability and the critical role of knowledge management capability on innovation strategy of SMEs considering environmental dynamism.
Couples’ experiences of using DemPower in everyday life
Authors: Bielsten Therése , Keady John , Kullberg Agneta , Lasrado Reena , Hellström Ingrid
Published: August 2020

Purpose

Interventions aimed at couples where one partner has dementia are often targeting burden, depression and cognitive function and do not focus on relationship and interpersonal issues. Furthermore, interventions within this population do not seem to have embraced a salutogenic and authentic dyadic approach where both partners’ experiences are considered. To address this gap, a self-management app, DemPower, which was piloted and tested among couples where one partner has dementia living at home, has been developed. This study explores couples‘ everyday experiences of engaging with the DemPower.

Design/methodology/approach

Semi-structured interviews with couples were analysed using thematic analysis.

Findings

The findings resulted in the following themes: growth of the relationship; we are not alone; and positive approach. The findings indicated that the experiences of a salutogenic and dyadic intervention can contribute to the feelings of empowerment, satisfaction of couples’ achievements and a sense of support through peers and with the intervention itself.

Originality/value

The findings of this study indicate that couples where one partner has dementia appreciate interventions that focuses on a salutogenic approach to their everyday life and relationship. The dyadic intervention contributed to feelings of empowerment, satisfaction of couples’ achievements and a sense of support through peers and through the intervention itself. Discussing, inventory and focus on strengths, resources and quality of life can therefore give couples insight in their growth of the relationship and their transitions during the dementia trajectory. Furthermore, this study can serve as an eye opener in health care for the type of support couples need and wishes to receive. This means that care for people with dementia and partners should adopt a more health-promoting approach.
The role of universities in times of crisis: a vice-chancellor's perspective
Authors: Dewar John
Published: August 2020

Purpose

University responses to crises range from providing practical support to affected students and staff; providing leadership to the community; contributing to the development of government policy; developing new knowledge; establishing new qualifications to reskill the workforce in areas of need; and working with industry partners to solve commercial and manufacturing problems.

Design/methodology/approach

Universities play a vital role in times of crisis. This undertaking is exemplified by the important contribution made by universities to the societal response to recent crisis events including bushfires and the COVID-19 pandemic. It is not surprising that universities play this role, however, because it is a natural extension of a modern university's mission of promoting sustainable development and making positive contributions to the communities which it serves. Importantly, the role of universities is multifaceted and encompasses both applied and theoretical elements.

Findings

Each of these responses demonstrates the way that modern universities have become permeable institutions that are responsive to society and the people around them.

Originality/value

This is an original opinions piece.
Income comparison and happiness: The role of fair income distribution
Authors: Chen Yongwei , Fu Dahai , Ye Xinyue
Published: August 2020

Relative income gap is one of the most popular approaches for explaining the income–happiness relationship. We argue in this article that when people compare their incomes, they care about distributional fairness more than relative income disparity. It is difficult for us to explain China's income–happiness paradox if we simply compare the income gap and do not explore the income‐generation process leading to income inequality. We therefore employ an approach based on a responsibility‐sensitive theory of justice that decomposes individual income into fair and unfair components. As a proxy for distributional unfairness, unfair income is considered the main source of unhappiness. Using data from the Chinese Household Income Project survey, we find strong support for the negative relationship between income unfairness and happiness. We also find a significantly positive relationship between the relative income gap and income unfairness, which leads us to consider the income comparison hypothesis as the explanation for the income–happiness paradox in a new light. Sensitivity analyses confirm the robustness of our results.
Local house price comovements
Authors: Fischer Marcel , Füss Roland , Stehle Simon
Published: August 2020

We study the microlevel evolution of residential house prices using data on repeat sales on Manhattan Island from 2004 to 2015. We document that price comovement, even within a ZIP code, is a highly local and persistent phenomenon. The strength of such comovements vanishes with both spatial and temporal distance. Local underperformance is more persistent than local overperformance, particularly when house prices on aggregate level increase.
Rib Variation at Multiple Locations and Implications for Histological Age Estimation*
Authors: Dominguez Victoria M. , Harden Angela L. , Wascher Matthew , Agnew Amanda M.
Published: August 2020

Existing histological age estimation methods using the rib were developed mainly from the midshaft; however, in forensic practice, uncertainty of sampling location often arises due to fragmented or previously sampled ribs. The potential for error increases when sampling location is uncertain and utilizing a section beyond the midshaft (either anterior or posterior) may result in erroneous age estimates. Additionally, there is debate within the field regarding the minimum number of sections needed for accurate age estimation. The aim of this research is to determine the importance of the midshaft distinction for age‐at‐death assessment and the necessity of analyzing serial sections by evaluating histological variables at sampling locations along the length of the rib. Three seriated histological sections at three sampling locations (anterior, midshaft, and posterior) were obtained from sixth ribs of ten postmortem human subjects. Cortical area (Ct.Ar) and osteon population density (OPD) were collected from each section (n = 90). Significant differences were determined in Ct.Ar between sampling locations, demonstrating the variation present along the length of the rib. A comparison of OPD at sampling locations revealed significant differences, suggesting that sampling site is critical to accurate age estimates. When sampling location is uncertain, a more anterior section should be taken. Analysis of serial sections within locations revealed no significant differences in OPD or Ct.Ar, supporting the practice of collecting data from one section for age estimation. While an age estimate can be achieved through the analysis of one section, best practice suggests reading two sections to capture intraindividual variation.
Nemo‐age: Spatially explicit simulations of eco‐evolutionary dynamics in stage‐structured populations under changing environments
Authors: Cotto Olivier , Schmid Max , Guillaume Frédéric
Published: August 2020

Anticipating and preparing for the effect of environmental changes on biodiversity requires to understand and predict both the ecological and evolutionary responses of populations. Tools and methods to efficiently integrate these complex processes are lacking.

We present the genetically and spatially explicit individual‐based simulation software Nemo‐age combining ecological and evolutionary processes. Nemo‐age has a strong emphasis on modelling complex life histories. We here provide a methodology to predict changes in species distribution for given climate projections using Nemo‐age.

Modelling complex life histories, spatial distribution and evolutionary processes unravel possible eco‐evolutionary mechanisms that have been previously overlooked when populations endure rapid environmental changes.

The interface of Nemo‐age is designed to integrate species' data from different fields, from demography to genetic architecture and spatial distributions, thus representing a versatile tool to model a variety of applied and theoretical scenarios.
Attenuation of epigenetic regulator SMARCA4 and ERK‐ETS signaling suppresses aging‐related dopaminergic degeneration
Authors: Sun Ling , Zhang Jie , Chen Wenfeng , Chen Yun , Zhang Xiaohui , Yang Mingjuan , Xiao Min , Ma Fujun , Yao Yizhou , Ye Meina , Zhang Zhenkun , Chen Kai , Chen Fei , Ren Yujun , Ni Shiwei , Zhang Xi , Yan Zhangming , Sun Zhi‐Rong , Zhou Hai‐Meng , Yang Hongqin , Xie Shusen , Haque M. Emdadul , Huang Kun , Yang Yufeng
Published: August 2020

How complex interactions of genetic, environmental factors and aging jointly contribute to dopaminergic degeneration in Parkinson's disease (PD) is largely unclear. Here, we applied frequent gene co‐expression analysis on human patient substantia nigra‐specific microarray datasets to identify potential novel disease‐related genes. In vivo Drosophila studies validated two of 32 candidate genes, a chromatin‐remodeling factor SMARCA4 and a biliverdin reductase BLVRA. Inhibition of SMARCA4 was able to prevent aging‐dependent dopaminergic degeneration not only caused by overexpression of BLVRA but also in four most common Drosophila PD models. Furthermore, down‐regulation of SMARCA4 specifically in the dopaminergic neurons prevented shortening of life span caused by α‐synuclein and LRRK2. Mechanistically, aberrant SMARCA4 and BLVRA converged on elevated ERK‐ETS activity, attenuation of which by either genetic or pharmacological manipulation effectively suppressed dopaminergic degeneration in Drosophila in vivo. Down‐regulation of SMARCA4 or drug inhibition of MEK/ERK also mitigated mitochondrial defects in PINK1 (a PD‐associated gene)‐deficient human cells. Our findings underscore the important role of epigenetic regulators and implicate a common signaling axis for therapeutic intervention in normal aging and a broad range of age‐related disorders including PD.
Cocaine memory reactivation induces functional adaptations within parvalbumin interneurons in the rat medial prefrontal cortex
Authors: Jorgensen Emily T. , Gonzalez Angela E. , Harkness John H. , Hegarty Deborah M. , Thakar Amit , Burchi Delta J. , Aadland Jake A. , Aicher Sue A. , Sorg Barbara A. , Brown Travis E.
Published: August 2020

Substance use disorder is a complex disease created in part by maladaptive learning and memory mechanisms following repeated drug use. Exposure to drug‐associated stimuli engages prefrontal cortex circuits, and dysfunction of the medial prefrontal cortex (mPFC) is thought to underlie drug‐seeking behaviors. Growing evidence supports a role for parvalbumin containing fast‐spiking interneurons (FSI) in modulating prefrontal cortical microcircuit activity by influencing the balance of excitation and inhibition, which can influence learning and memory processes. Most parvalbumin FSIs within layer V of the prelimbic mPFC are surrounded by specialized extracellular matrix structures called perineuronal nets (PNN). Previous work by our group found that cocaine exposure altered PNN‐surrounded FSI function, and pharmacological removal of PNNs reduced cocaine‐seeking behavior. However, the role of FSIs and associated constituents (parvalbumin and PNNs) in cocaine‐related memories was not previously explored and is still unknown. Here, we found that reactivation of a cocaine conditioned place preference memory produced changes in cortical PNN‐surrounded parvalbumin FSIs, including decreased parvalbumin intensity, increased parvalbumin cell axis diameter, decreased intrinsic excitability, and increased excitatory synaptic input. Further investigation of intrinsic properties revealed changes in the interspike interval, membrane capacitance, and afterhyperpolarization recovery time. Changes in these specific properties suggest an increase in potassium‐mediated currents, which was validated with additional electrophysiological analysis. Collectively, our results indicate that cocaine memory reactivation induces functional adaptations in PNN‐surrounded parvalbumin neurons, which likely alters cortical output to promote cocaine‐seeking behavior.