bluuebunny/crossref_metadata_2025_split huggingface dataset:
Lysosomal activity regulatesCaenorhabditis elegansmitochondrial dynamics through vitamin B12 metabolism
Authors: Wei Wei , Ruvkun Gary 
Published: April 2020

ABSTRACTMitochondrial fission and fusion are highly regulated by energy demand and physiological conditions to control the production, activity, and movement of these organelles. Mitochondria are arrayed in a periodic pattern inCaenorhabditis elegansmuscle, but this pattern is disrupted by mutations in the mitochondrial fission component dynamin. Here we show that the dramatically disorganized mitochondria caused by a mitochondrial fission-defective dynamin mutation is strongly suppressed to a more periodic pattern by a second mutation in lysosomal biogenesis or acidification. Vitamin B12 is normally imported from the bacterial diet via lysosomal degradation of B12-binding proteins and transport of vitamin B12 to the mitochondrion and cytoplasm. We show that the lysosomal dysfunction induced by gene inactivations of lysosomal biogenesis or acidification factors causes vitamin B12 deficiency. Growth of theC. elegansdynamin mutant on anE. colistrain with low vitamin B12 also strongly suppressed the mitochondrial fission defect. Of the twoC. elegansenzymes that require B12, gene inactivation of methionine synthase suppressed the mitochondrial fission defect of a dynamin mutation. We show that lysosomal dysfunction induced mitochondrial biogenesis which is mediated by vitamin B12 deficiency and methionine restriction. S-adenosylmethionine, the methyl donor of many methylation reactions, including histones, is synthesized from methionine by S-adenosylmethionine synthase; inactivation of thesams-1S-adenosylmethionine synthase also suppresses thedrp-1fission defect, suggesting that vitamin B12 regulates mitochondrial biogenesis and then affects mitochondrial fission via chromatin pathways.SIGNIFICANCE STATEMENTThe balance of mitochondrial fission and fusion, two aspects of mitochondrial dynamics, is important for mitochondrial function. Here we show thatCaenorhabditis eleganslysosomal activity regulates mitochondrial dynamics by affecting mitochondrial fission through interfering the metabolism of a micronutrient, vitamin B12. Vitamin B12 is exclusively obtained from diets in animals includingC. elegansand humans, and its uptake is mediated by the lysosome. We show that lysosomal dysfunction causes vitamin B12 deficiency that leads to reduction of methionine and S-adenosylmethionine to in turn increase mitochondrial biogenesis and fission. Our study provides an insight on the interactions between mitochondrial function and micronutrient metabolism.
Navigating the translational roadblock: Towards highly specific and effective all-optical interrogations of neural circuits
Authors: Fu Ting , Arnoux Isabelle , Döring Jan , Watari Hirofumi , Stasevicius Ignas , Stroh Albrecht 
Published: April 2020

AbstractTwo-photon (2-P) all-optical approaches combinein vivo2-P calcium imaging and 2-P optogenetic modulations and have the potential to build a framework for network-based therapies, e.g. for rebalancing maladaptive activity patterns in preclinical models of neurological disorders. Here, our goal was to tailor these approaches for this purpose: Firstly, we combinedin vivojuxtacellular recordings and GCaMP6f-based 2-P calcium imaging in layer II/III of mouse visual cortex to tune our detection algorithm towards a 100 % specific identification of AP-related calcium transients. False-positive-free detection was achieved at a sensitivity of approximately 73 %. To further increase specificity, secondly, we minimized photostimulation artifacts as a potential source for false-positives by using extended-wavelength-spectrum laser sources for optogenetic stimulation of the excitatory opsin C1V1. We achieved artifact-free all-optical experiments performing photostimulations at 1100 nm or higher and simultaneous calcium imaging at 920 nm in mouse visual cortexin vivo. Thirdly, we determined the spectral range for maximizing efficacy of optogenetic control by performing 2-P photostimulations of individual neurons with wavelengths up to 1300 nm. The rate of evoked transients in GCaMP6f/C1V1-co-expressing cortical neurons peaked already at 1100 nm. By refining spike detection and defining 1100 nm as the optimal wavelength for artifact-free and effective stimulations of C1V1 in GCaMP-based all-optical interrogations, we increased the translational value of these approaches, e.g. for the use in preclinical applications of network-based therapies.One Sentence SummaryWe maximize translational relevance of 2-P all-optical physiology by increasing specificity, minimizing artifacts and optimizing stimulation efficacy.
Generation of cardiac valve endocardial like cells from human pluripotent stem cells
Authors: Cheng LX , Song Y , Zhang YY , Geng YC , Xu WL , Wang Z , Wang L , Huang K , Dong NG , Sun YH 
Published: April 2020

AbstractThe cardiac valvular endothelial cells (VECs) are an ideal cell source that could be used for the fabrication of the next generation tissue-engineered cardiac valves (TEVs). However, few studies have been focused on the derivation of this important cell type. Here we describe a chemically defined xeno-free method for generating VEC-like cells from human pluripotent stem cells (hPSCs) through an intermediate endocardium stage. HPSCs were initially specified to KDR+/ISL1+multipotent cardiac progenitor cells (CPCs), followed by differentiation into endocardial progenitors under the combined treatment with VEGFA, BMP4 and bFGF. In the presence of VEGFA, BMP4 and TGFb, valve endocardial progenitor cells (VEPs) were efficiently derived from endocardial progenitors without a sorting step. Mechanistically, administration of TGFb and BMP4 may specify the VEP fate by facilitating the expression of key transcription factors ETV2 and NFATc1 at the immediate early stage and by activating Notch signaling at the later stage. Notch activation is likely an important part of VEP induction. HPSC-derived VEPs exhibited morphological, molecular and functional similarities to that of the primary VECs isolated from normal human aortic valves. When hPSC-derived VEPs were seeded onto the surface of the de-cellularized porcine aortic valve (DCV) matrix scaffolds, they exhibited higher proliferation and survival potential than the primary VECs. Our results suggest that hPSC-derived VEPs could serve as as a potential platform for the study of valve development, and as starting materials for the construction of the next generation TEVs.HighlightsValve endocardial progenitor cells (VEPs) could be efficiently derived from hPSCs without a sorting stepThe combined treatment with TGFb and BMP4 induce VEP fate by enhancing the expression ofETV2andNFATc1HPSC-derived VEPs resemble the isolated primary VECs molecularly, morphologically and functionallyHPSC-derived VEPs exhibit proliferative and functional potential similar to the primary VECs when seeded onto the DCVs
Aspect context aware sentiment classification of online consumer reviews
Authors: Bansal Barkha , Srivastava Sangeet 
Published: April 2020

PurposeAspect based sentiment classification is valuable for providing deeper insight into online consumer reviews (OCR). However, the majority of the previous studies explicitly determine the orientation of aspect related sentiment bearing word and overlook the aspect-context. Therefore, this paper aims to propose an aspect-context aware sentiment classification of OCR for deeper and more accurate insights.Design/methodology/approachIn the proposed methodology, first, aspect descriptions and sentiment bearing words are extracted. Then, the skip-gram model is used to extract the first set of features to capture contextual information. For the second category of features, cosine similarity is used between a pre-defined seed word list and aspects, to capture aspect context sensitive sentiments. The third set of features includes weighted word vectors using term frequency-inverse document frequency. After concatenating features, ensemble classifier is used using three base classifiers.FindingsExperimental results on two real-world data sets with variable lengths, acquired from Amazon.com and TripAdvisor.com, show that the advised ensemble approach significantly outperforms sentiment classification accuracy of state-of-the-art and baseline methods.Originality/valueThis method is capable of capturing the correct sentiment of ambiguous words and other special words by extracting aspect-context using word vector similarity instead of expensive lexical resources, and hence, shows superior performance in terms of accuracy as compared to other methods.
Two-stage incentives system for commercial banks based on centralized resource allocation model in DEA-R
Authors: Kamyab Parisa , Mozaffari Mohammad Reza , Gerami Javad , Wankei Peter F. 
Published: April 2020

PurposeIt is always of great importance for managers in organizations to evaluate their staff members and create incentive systems, using instruments such as Data Envelopment Analysis (DEA) and DEA-R (DEA models based on ratio analysis). The purpose of this paper is to propose a two-stage network incentives system for commercial banks.Design/methodology/approachCentralized Resource Allocation (CRA) models make it possible to project all decision-making units (DMUs) onto the efficient frontier by solving a single linear programming model. In this paper, we use our proposed DEA-R-based CRA models to evaluate commercial banks in a two-stage case when the only ratios available are the assets-to-costs and income-to-assets vectors.FindingsThirteen commercial banks modeled as two-stage networks were evaluated by the models proposed in two different cases of ratio data. Results suggest that the proposed methodology yields more accurate efficiency scores, thus allowing better discrimination among DMUs. Furthermore, evaluating the DMUs when they are structured as two-stage (or even three-stage) networks makes it possible to examine the incentives system in more detail. Therefore, the use of incentive systems by managers would allow a better focus on the priority activities of commercial banks and a faster movement toward the frontier of best practices.Originality/valueThe super-efficiency scores of a number of commercial banks are evaluated based on the CRA model, as a cornerstone criterion for the two-stage evaluation in DEA-R, thus allowing the rank of each commercial bank in terms of the incentives system rather on the performance of the productive process.
Assessing the moderating effect of subjective norm on luxury purchase intention: a study of Gen Y consumers in India
Authors: Jain Sheetal 
Published: April 2020

PurposeAlthough Generation Y consumers contribute significantly to the luxury market, still there is a limited amount of research conducted to explain their luxury consumption behavior, particularly in context of emerging markets like India. The main objectives of this study are to understand the key factors that affect luxury purchase intentions of Generation Y consumers using the theory of planned behavior (TPB) and to examine the moderating effect of subjective norm on other TPB variables, namely, attitude and perceived behavioral control.Design/methodology/approachPurposive sampling method was used to collect data from Generation Y luxury fashion consumers in New Delhi, India. Confirmatory factor analysis and structural equation modeling was employed to analyze the data.FindingsThe findings of this study revealed subjective norm and perceived behavioral control were positively related to luxury purchase intentions. Further, subjective norm was found to moderate the relationship between attitude and luxury purchase intentions.Originality/valueThis study will help consumer behavior researchers and practitioners to understand the core reason behind luxury purchase intentions of Generation Y consumers in India. It will enable luxury brand companies to create suitable marketing strategies which align with the mindset of this new demographic segment.
The relationship between Bitcoin returns, volatility and volume: asymmetric GARCH modeling
Authors: Sapuric Svetlana , Kokkinaki Angelika , Georgiou Ifigenia 
Published: April 2020

PurposeTo show that when volume of trades is taken into consideration, Bitcoin does not seem as volatile as it claimed. Further, to study the relationship between Bitcoin trading volume, volatility and returns, and the asymmetry in response to economic information for the period from July 2010 to November 2017.Design/methodology/approachComparison of Bitcoin price volatility with that of six currencies and gold. We repeat the analysis using returns divided by volume. We examine the relationship between volume, returns and volatility, and the asymmetry of the reaction of the volatility to economic news using asymmetric models (EGARCH) run for four meaningful distinct time periods/subsamples.FindingsPositive and significant relationship between (1) volume and volatility after 2013 (year Bitcoin became popular) and (2) volume and returns before the Mt. Gox hack. During the euphoric period, starting at the beginning of 2013 until the Mt. Gox hack, unexpected increases in Bitcoin returns increased Bitcoin volatility more than unexpected, equally sized decreases (asymmetry).Originality/valueWe take into consideration the volume of trades to show that Bitcoin volatility seems high because of the low volume of trades. We study an extended time period, not covered by other studies. We divide our sample into four meaningful time periods based on important events in Bitcoin market history. This is important for a new market such as the Bitcoin market; the relationships under study are very important in markets where participants rely on technical analysis in the absence of reliable fundamental methodology to measure the intrinsic value of the asset.
People with dementia and carers online discussing surveillance
Authors: Vermeer Yvette , van Santen Joeke , Charlesworth Georgina , Higgs Paul 
Published: April 2020

Purpose
This paper aims to interrogate online comments from consumers with dementia and family carers on surveillance technology products used by or for people with dementia.

Design/methodology/approach
A naturalistic, observational study of qualitative posts (N = 120) by people with dementia (n = 7) and family carers (n = 38) to discussion threads on surveillance technology (ST), hosted by an online dementia support forum in the Netherlands. Kozinet’s (2002) typology was used to describe respondent characteristics, and comments on features of ST products were analysed within a pre-existing framework.

Findings
Forum users were mainly “tourists” interested in ST, with some “insiders” interested in sharing experiences of ST use. They expressed a lack of trust in information from marketers and providers to the experience of being provided with poor information. Consumer-to-consumer comments on products triangulated with previous face-to-face qualitative studies. Carers prioritised “peace of mind” through location monitoring. In contrast, people with dementia prioritised user-friendliness (simple, with capability and compatible with daily routines).

Practical implications
Using online discussions of ST products provides a rapid approach to understanding current consumer needs and preferences in the ever-changing world of technology.

Originality/value
No previous study is known to have explored the views of carers and people with dementia in online discussions about ST.
Ethical practice in sharing and mining medical data
Authors: Watson Kevin , Payne Dinah M. 
Published: April 2020

Purpose
The purpose of this paper is to review current practice in sharing and mining medical data revealing benefits, costs and ethical issues. Based on stakeholder perspectives and values, the authors create an ethical code to regulate the sharing and mining of medical information.

Design/methodology/approach
The framework is based on a review of academic, practitioner and legal research.

Findings
Owing to the inability of current safeguards to protect consumers from risks related to the disclosure of medical information, the authors develop a framework for ethical sharing and mining of medical data, security, transparency, respect, accountability, community and quality (STRACQ), which espouses security, transparency, respect, accountability, community and quality as the basic tenets of ethical data sharing and mining practice.

Research limitations/implications
The STRACQ framework is an original, previously unpublished contribution that will require modification over time based on discussion and debate within and among the academy, medical community and public policymakers.

Social implications
The framework for sharing borrows from the Fair Credit Reporting Act, allowing the collection and dissemination of identified medical data but placing strict limitations on use. Following this framework, benefits of shared and mined medical data are freely available with appropriate safeguards for consumer privacy.

Originality/value
Mandates for adoption of electronic health-care records require an understanding of medical data mining. This paper presents a review of data mining techniques and reasons for engaging in the practice of identifying benefits, costs and ethical issues. The authors create an original framework, STRACQ, for ethical sharing and mining of medical information, allowing knowledge exploration while protecting consumer privacy.
Leader humility and employee organizational deviance: the role of sense of power and organizational identification
Authors: Qiuyun Guo , Liu Wenxing , Zhou Kong , Mao Jianghua 
Published: April 2020

PurposeThe authors examined the relationship between leader humility and employee organizational deviance. They also tested the mediating effects of personal sense of power and the moderating effects of organizational identification on this relationship.Design/methodology/approachThe authors tested their hypotheses using a sample of 186 employees from an information technology (IT) enterprise in China. They used hierarchical regression and bootstrapping analyses to test for direct and indirect relationships.FindingsSense of power mediated the effect of leader humility on organizational deviance and organizational identification moderated the effect of sense of power on organizational deviance. In addition, organizational identification mediated the indirect effect of leader humility on organizational deviance via sense of power. Thus, employees who demonstrate high organizational identification may not conduct organizational deviant behavior, even if they have a high sense of power.Practical implicationsOrganizations should explore and practice effective leader humility. Selection and training programs should be developed to choose humble leaders and teach them how to exhibit moderate humility.Originality/valueThe authors contribute to the literature by revealing the negative effects of leader humility in Chinese culture. They find support for their hypotheses that employee sense of power mediates the relationship between leader humility and employee organizational deviance and that this relationship is weaker when employee organizational identification is higher. This clarifies how and why leader humility stimulates employee organizational deviance.
Reverse logistics risk management: identification, clustering and risk mitigation strategies
Authors: Panjehfouladgaran Hamidreza , Lim Stanley Frederick W.T. 
Published: April 2020

PurposeReverse logistics (RL), an inseparable aspect of supply chain management, returns used products to recovery processes with the aim of reducing waste generation. Enterprises, however, seem reluctant to apply RL due to various types of risks which are perceived as posing an economic threat to businesses. This paper draws on a synthesis of supply chain and risk management literature to identify and cluster RL risk factors and to recommend risk mitigation strategies for reducing the negative impact of risks on RL implementation.Design/methodology/approachThe authors identify and cluster risk factors in RL by using risk management theory. Experts in RL and supply chain risk management validated the risk factors via a questionnaire. An unsupervised data mining method, self-organising map, is utilised to cluster RL risk factors into homogeneous categories.FindingsA total of 41 risk factors in the context of RL were identified and clustered into three different groups: strategic, tactical and operational. Risk mitigation strategies are recommended to mitigate the RL risk factors by drawing on supply chain risk management approaches.Originality/valueThis paper studies risks in RL and recommends risk management strategies to control and mitigate risk factors to implement RL successfully.
Competition's impact on research and development real activities earnings management
Authors: Barber Russell , Hollie Dana 
Published: April 2020

PurposeThe purpose of this study is twofold: (1) to examine the incremental contribution of product market fluidity (P_THREAT), another measure of competition from that of the Herfindahl index (H_COMP) and (2) to examine how a research and development (R&D) real activities earnings management strategy to meet an earnings target is influenced by competition.Design/methodology/approachUsing a linear probability model, we test whether P_THREAT is incremental to the H_COMP competition measure and whether it influences the likelihood of firms using abnormally low R&D real activities earnings management to meet an earnings target.FindingsWe find that P_THREAT is incrementally informative to the commonly used Herfindahl measure of competition in predicting abnormally low R&D real activities earnings management activities. This finding is consistent with the notion of examining P_THREAT because the Herfindahl index alone may be incomplete, depending on the product makeup of a company. The negative coefficient suggests that reducing discretionary spending on R&D in the short run could have a detrimental effect on long-term profits because bypassed R&D opportunities would put firms at a disadvantage with their competitors' R&D efforts. In contrast, we find that firms are more likely to use R&D activities earnings management as a mechanism to meet an earnings target when P_THREAT is high. This suggests that when high competitive pressure exists, firms are more likely to use abnormally low R&D as a mechanism to meet an earnings target.Originality/valueWe specifically focus on R&D activities earnings management because our primary competition measure, P_THREAT, captures changes in rival firms' products relative to the firm. Because R&D is primarily what drives product change, R&D is the type of real activities earnings management that is most relevant to our competition measure. Hence, this study contributes to the literature by examining how competition influences the likelihood of firms possibly engaging in R&D activities earnings management and meeting earnings targets in the presence of P_THREAT competition.