bluuebunny/crossref_metadata_2025_split huggingface dataset:
4-state model for simulating kinetic and steady-state voltagedependent gating of gap junctions
Authors: Snipas M. , Kraujalis T. , Maciunas K. , Kraujaliene L. , Gudaitis L. , Verselis V. K. 
Published: October 2019

AbstractGap junction (GJ) channels, formed of connexin (Cx) proteins, provide a direct pathway for metabolic and electrical cell-to-cell communication. These specialized channels are not just passive conduits for the passage of ions and metabolites, but have been shown to gate robustly in response to transjunctional voltage, Vj, the voltage difference between two coupled cells and are regulated by various chemical factors. Voltage gating of GJs may play a physiological role, particularly in excitable cells which can exhibit large transients in membrane potential during the generation of an action potential. We present a mathematical/computational model of GJ channel voltage gating to assess properties of GJ channels that takes into account contingent gating of two series hemichannels and the distribution of Vj across each hemichannel. From electrophysiological recordings in cell cultures transfected with Cx43 and Cx45, isoforms that are expressed in cardiac tissue, data sets were fit simultaneously using global optimization. The results showed that the model is capable of describing both steady-state and kinetic properties of homotypic and heterotypic GJ channels composed of these connexins. Moreover, mathematical analyses showed that the model can be simplified to a reversible two-state system and solved analytically, using a rapid equilibrium assumption. Given that excitable cells are arranged in interconnected networks, the equilibrium assumption allows for a substantial reduction in computation time, which is useful in simulations of large clusters of coupled cells. Overall, this model can serve not just as a modeling tool, but also to provide a means of testing GJ channel gating behavior.SignificanceGap junction (GJ) channels gate in response to transjunctional voltage which provides the capacity for dynamic regulation of intercellular coupling. Kinetic properties of GJs in modeling studies have been infrequently addressed and we present a computational model of voltage gating that can account for both kinetic and steady-state changes in junctional conductance, gj. Although GJs possess two gating mechanisms, our analysis indicates that changes in gj for each voltage polarity can be adequately described by a kinetic scheme describing a single mechanism in each of the hemichannels, suggesting functional dominance of one mechanism over a substantial voltage range. This property allowed for model simplification that can be applied for efficient simulation of sizeable cell clusters and analyses of electrophysiological data.
Antibody-Recruiting Protein-Catalyzed Capture Agents to Combat Antibiotic-Resistant Bacteria
Authors: Idso Matthew N. , Akhade Ajay Suresh , Arrieta-Ortiz Mario L. , Lai Bert T. , Srinivas Vivek , Hopkins James P. , Gomes Ana Oliveira , Subramanian Naeha , Baliga Nitin , Heath James R. 
Published: October 2019

AbstractAntibiotic resistant infections are projected to cause over 10 million deaths by 2050, yet the development of new antibiotics has slowed. This points to an urgent need for methodologies for the rapid development of antibiotics against emerging drug resistant pathogens. We report on a generalizable combined computational and synthetic approach, called antibody-recruiting protein-catalyzed capture agents (AR-PCCs), to address this challenge. We applied the combinatorial PCC technology to identify macrocyclic peptide ligands against highly conserved surface protein epitopes of carbapenem-resistant Klebsiella pneumoniae, an opportunistic gram-negative pathogen with drug resistant strains. Multi-omic data combined with bioinformatic analyses identified epitopes of the highly expressed MrkA surface protein of K. pneumoniae for targeting in PCC screens. The top-performing ligand exhibited high-affinity (EC50∼50 nM) to full-length MrkA, and selectively bound to MrkA-expressing K. pneumoniae, but not to other pathogenic bacterial species. AR-PCCs conjugated with immunogens promoted antibody recruitment to K. pneumoniae, leading to phagocytosis and phagocytic killing by macrophages. The rapid development of this highly targeted antibiotic implies that the integrated computational and synthetic toolkit described here can be used for the accelerated production of antibiotics against drug resistant bacteria.
NADPH and glutathione redox link TCA cycle activity to endoplasmic reticulum stress
Authors: Gansemer Erica R. , McCommis Kyle S. , Martino Michael , King-McAlpin Abdul Qaadir , Potthoff Matthew J. , Finck Brian N. , Taylor Eric B. , Rutkowski D. Thomas 
Published: October 2019

AbstractEndoplasmic reticulum (ER) stress is associated with dysregulated metabolism, but little is known about how the ER responds to metabolic activity. Here, working primarily in mouse hepatocytes, we show that decreasing the availability of substrate for the TCA cycle diminished NADPH production and attenuated ER stress in a manner that depended on glutathione oxidation. ER stress was also alleviated by impairing either TCA-dependent NADPH production or Glutathione Reductase. Conversely, stimulating TCA activity favored NADPH production, glutathione reduction, and ER stress. Validating these findings, we show that deletion of the mitochondrial pyruvate carrier, which is known to decrease TCA cycle activity and protect the liver from diet-induced injury, also diminished NADPH, elevated glutathione oxidation, and alleviated ER stress. These results provide independent genetic evidence that mitochondrial oxidative metabolism is linked to ER homeostasis. Our results demonstrate a novel pathway of communication between mitochondria and the ER, through relay of redox metabolites.
Self-assembly of multi-component mitochondrial nucleoids via phase separation
Authors: Feric Marina , Demarest Tyler G. , Tian Jane , Croteau Deborah L. , Bohr Vilhelm A. , Misteli Tom 
Published: October 2019

SummaryMitochondria contain an autonomous and spatially segregated genome. The organizational unit of their genome is the nucleoid, which consists of mitochondrial DNA (mtDNA) and associated architectural proteins. Here, we show that phase separation is the primary physical mechanism for assembly and size-control of the mitochondrial nucleoid. The major mtDNA-binding protein TFAM spontaneously phase separatesin vitrovia weak, multivalent interactions into viscoelastic droplets with slow internal dynamics. In combination, TFAM and mtDNA form multiphase, gel-like structuresin vitro, which recapitulate thein vivodynamic behavior of mt-nucleoids. Enlarged, phase-separated, yet transcriptionally active, nucleoids are present in mitochondria from patients with the premature aging disorder Hutchinson-Gilford Progeria Syndrome (HGPS) and are associated with mitochondrial dysfunction. These results point to phase separation as an evolutionarily conserved mechanism of genome organization.HighlightsMitochondrial genomes are organized by phase separation.The main packaging protein TFAM and mtDNA combine to form viscoelastic, multiphase dropletsin vitro.Mitochondrial nucleoids exhibit phase behaviorin vivo, including dynamic rearrangements and heterogenous organization.Coalescence and enlargement of mt-nucleoids occur upon loss of mitochondrial homeostasis as well as in prematurely aged cells and are associated with mitochondrial dysfunction.
The population and evolutionary dynamics of bacteriophage: Why be temperate revisited
Authors: Chaudhry Waqas , Vega Nicole , Govindan Adithi , Garcia Rodrigo , Lee Esther , McCall Ingrid , Levin Bruce 
Published: October 2019

AbstractBacteriophages are deemed either lytic (virulent) or temperate, respectively depending on whether their genomes are transmitted solely horizontally, or both horizontally and vertically. To elucidate the ecological and evolutionary conditions under which natural selection will favor the evolution and maintenance of lytic or temperate modes of phage replication and transmission, we use a comprehensive mathematical model of the dynamics of temperate and virulent phage in populations of bacteria sensitive and resistant to these viruses. For our numerical analysis of the properties of this model, we use parameters estimated with the temperate bacteriophage Lambda, λ, it’s clear and virulent mutants, andE. colisensitive and resistant - refractory to these phages. Using batch and serial transfer population dynamic and reconstruction experiments, we test the hypotheses generated from this theoretical analysis. Based on the results of this jointly theoretical and experimental study, we postulate the conditions under which natural selection will favor the evolution and maintenance of lytic and temperate modes of phage replication and transmission. A compelling and novel prediction thisin silico,in vitro, andin plasticostudy makes is lysogenic bacteria from natural populations will be resistant-refractory to the phage for which they are lysogenic as well as lytic phage sharing the same receptors as these temperate viruses.
An Improved Recombineering Toolset for Plants
Authors: Brumos Javier , Zhao Chengsong , Gong Yan , Soriano David , Patel Arjun P. , Perez-Amador Miguel A. , Stepanova Anna N. , Alonso Jose M. 
Published: October 2019

Abstract
Gene functional studies often rely on the expression of a gene of interest as transcriptional and translational fusions with specialized tags. Ideally, this is done in the native chromosomal contexts to avoid potential misexpression artifacts. Although recent improvements in genome editing have made it possible to directly modify the target genes in their native chromosomal locations, classical transgenesis is still the preferred experimental approach chosen in most gene tagging studies because of its time efficiency and accessibility. We have developed a recombineering-based tagging system that brings together the convenience of the classical transgenic approaches and the high degree of confidence in the results obtained by direct chromosomal tagging using genome-editing strategies. These simple, scalable, customizable recombineering toolsets and protocols allow a variety of genetic modifications to be generated. In addition, we developed a highly efficient recombinase-mediated cassette exchange system to facilitate the transfer of the desired sequences from a bacterial artificial chromosome clone to a transformation-compatible binary vector, expanding the use of the recombineering approaches beyond Arabidopsis (Arabidopsis thaliana). We demonstrated the utility of this system by generating more than 250 whole-gene translational fusions and 123 Arabidopsis transgenic lines corresponding to 62 auxin-related genes and characterizing the translational reporter expression patterns for 14 auxin biosynthesis genes.
Ethical work climate, organizational identification, leader-member-exchange (LMX) and organizational citizenship behavior (OCB)
Authors: Teng Chih-Ching , Lu Allan Cheng Chieh , Huang Zhi-Yang , Fang Chien-Hua 
Published: October 2019

PurposeThis paper aims to propose and test a moderated mediation model examining the relationships among ethical work climate, organizational identification, leader-member-exchange (LMX) and organizational citizenship behavior (OCB).Design/methodology/approachNumerous regression analyses were performed using PROCESS (version 2.13), a macro for SPSS developed by Hayes (2017) to test this moderated mediation model.FindingsThe analytical results showed that organizational identification mediates the positive relationship between an ethical work climate and OCB. The analytical results also showed that LMX moderates the direct effect of ethical work climate on organizational identification and that LMX also moderates the indirect effect of ethical work climate on OCB via organizational identification.Practical implicationsThis study provides numerous valuable implications for hotels to develop effective strategies to promote employees’ OCB and improve their organizational identification.Originality/valueThis study was the first attempt to propose and test a moderated mediation model that explores the relationships among ethical work climate, organizational identification, leader-member-exchange (LMX) and OCB.
Quality of work, economic crisis, and temporary employment
Authors: Bartoll Xavier , Ramos Raul 
Published: October 2019

Purpose
The purpose of this paper is to analyse the association between the type of contract (temporary vs permanent) and the quality of work and its different dimensions before and after the economic crisis among Spanish employees.

Design/methodology/approach
Structural equations techniques are used to analyse the association between the type of contract and the work quality and its different dimensions before and after the crisis. Data are drawn from the 2006/2007 and 2009/2010 waves of the Encuesta de Calidad de Vida en el Trabajo.

Findings
The results show that in the two considered periods there are no differences in quality of work among male involuntary temporary workers and those with permanent contracts. However, there is an adverse widening gap across all dimensions of work quality for women in involuntary temporary employment during the economic crisis. There is also a shift among men and women in involuntary temporary employment from valuing intrinsic job quality dimension in the pre-crisis period to valuing more the work environment dimension during the crisis period.

Research limitations/implications
The analysis is limited by the continuity of variables across years and the high proportion of missing values in some variables. The obtained results cannot be interpreted in terms of causality.

Originality/value
This is the first study to consider whether the deterioration in the Spanish labour market during the crisis has affected the relationship between the type of contract and the different dimensions of the quality of work.
Tribological properties of soft/hard hybrid surface of Babbitt alloy/steel
Authors: Ni Yuquan , Dong Guangneng , Liu Qi , Wang Wei , Li Yihong 
Published: October 2019

Purpose
Babbitt bush is easy to cause severe adhesive wear due to unexpected journal fall. This paper aims to improve wear resistance of Babbitt bush.

Design/methodology/approach
A soft/hard hybrid surface mircoprofile of Babbitt alloy/steel was fabricated by a technology of laser texture combined with hot-pressing. The friction and wear performances of bare steel (steel-h), Babbitt bush on steel (steel-s) and Babbitt filled in dimples of steel (steel-hs) were conducted on a ball-on-disc tester under dry and lubricated conditions.

Findings
The results showed that wettability of steel-hs was enhanced by forming soft/hard hybrid surface. Compared with steel-s, the stability of friction coefficient curve of steel-hs was improved without increasing coefficient friction. The wear resistance of steel-hs was remarkably enhanced under dry and lubricated conditions.

Originality/value
The originality of this paper is as following: to improve the tribological properties and to prolong service life of steel-s, soft/hard hybrid surface of Babbitt filled in dimples of steel substrate was successfully fabricated by laser texturing combined with hot-pressing. This paper showed that the lipophilicity of steel-hs was best among those of steel-s and steel-h. Babbitt alloy as a soft filler on dimples of steel substrate improved anti-wear of steel-s remarkably. It provides a new way to fabricate Babbitt as bushing on steel substrate.
Examining the efficiency of IT applications and bank performance
Authors: Owusu Kwateng Kwame , Agyei Joseph , Amanor Kofi 
Published: October 2019

Purpose
Banking institutions have vigorously pursued the integration of information and communication technology in modern banking services. Unfortunately, empirical support demonstrating the usefulness of this undertaking has largely been scanty. The purpose of this paper is to investigate causal links between the efficiency of information technology (IT) applications and bank performance using data envelopment analysis.

Design/methodology/approach
The study adopts the DEA approach to evaluate the bank level cost and IT efficiency. The Vector Error Correction Model Granger causality tests with the forecast error variance decomposition and impulse response functions were subsequently used to examine the causal relationship between the variables.

Findings
From the findings, the bank achieved an average level of 99.1 per cent cost efficiency for the sampled period. Also the periods where the bank obtained optimal cost efficiency were in 2005, 2006 and 2014. This culminated into inefficiency scores ranging from 0 to 2.9 per cent, with 2016 financial year as the period of worst cost performance. In addition, the study found that there are both short-run and long-run relationships between IT efficiency and cost performance.

Practical implications
Management should note that any improvement to IT applications may contribute significantly to overall IT performance but for the short period, specifically the first period, by the medium to long-run period, most improvement to overall IT performance emanates from cost performance of the bank.

Originality/value
Some studies have examined the effect of IT on banks in USA and Europe. However, such studies are rare in the African context. This study will contribute to extant literature by add a new dimension of IT and bank efficiency.
Improving occupational health and safety (OHS) in construction using Training-Within-Industry method
Authors: Mollo Lesiba George , Emuze Fidelis , Smallwood John 
Published: October 2019

Purpose
The manufacturing industry is a well-known source of interventions adapted to solve problems in the construction industry. The use of Training-Within-Industry (TWI) is one such intervention adopted in the construction industry to solve the construction problem relating to occupational health and safety (OHS). The objectives of TWI are to help the industry to transfer knowledge and skills from management to the employees. Therefore, the purpose of this paper was to investigate whether TWI can reduce OHS problems by promoting “learning by doing” on construction sites.

Design/methodology/approach
A case-based-research method was used to investigate the reported OHS problems in the construction industry in South Africa. The data were quantitative and qualitative in nature; the questionnaire survey, semi-structured interview and focus group interview techniques were used to collect data in the study.

Findings
The findings provide a better understanding of the human contributions influencing the behaviour of people causing accidents on construction sites. The data show that construction project leaders struggle to promote “learning by doing” because of inappropriate behaviour, lack of communication and inadequate training provided to new workers on construction sites. Also, there is significant scope for TWI deployment in construction because of the inability of supervisors or management to promote “learning by doing” on construction sites.

Practical implications
Based on the research findings, it is discovered that OHS is a serious concern in the construction industry. Therefore, the adoption of learning by doing on a construction site would help to improve OHS outcome.

Originality/value
The study highlights the need to introduce TWI on construction sites to reduce human failure causing accidents. TWI could lead to improving the knowledge- and skills-transfer programmes for construction workers in favour of better safety performance.
CSR disclosure in developing and developed countries: a comparative study
Authors: Bhatia Aparna , Makkar Binny 
Published: October 2019

PurposeThis paper aims to examine and compare the nature and extent of corporate social responsibility (CSR) reporting practices of companies in developing (BRICS [Brazil, Russia, India, China and South Africa]) and developed (the USA and the UK) countries.Design/methodology/approachContent analysis is conducted on the annual reports and websites of 325 companies listed on stock exchanges of developing markets and of developed markets (Brazil – IBrX 100, 46 companies; Russia – Broad Market Index, 50 companies; India – BSE 100, 50 companies; China – SSE 180, 29 companies; South Africa – FTSE/JSE All Share index, 50 companies; the USA – NYSE 100, 50 companies; the UK – FTSE 100, 50 companies). Descriptives are used to calculate company wise and item wise scores.T-test analysis is applied to check for significant differences between mean scores of developing and developed countries.FindingsThe findings of the study reflect that developed countries have higher CSR disclosure scores than developing countries. Overall, mean CSR disclosure score of developed countries is 53.5%, followed by that of the developing countries at 49.4%. Developed countries take lead in CSR disclosure for all the five categories, namely, human resources, community, environment, customer and product and others. The results of independent sampleT-test suggest that mean disclosure score of developing nations is significantly different from developed nations.Practical implicationsAs suggested by the results, the gap in the CSR disclosure scores between developing and developed group of countries is not an alarming one. However, developing countries should practice CSR in spirit and not just in letter. Focus should not be on just filling the pages in black and white, rather the essence of CSR should be attained for balanced development of the country. For instance, though developing country like India has high score of CSR disclosure in contrast to each of the developed country taken in the sample, yet the country is still battling with several issues such as poverty, over-population, corruption, poor standard of working conditions for the employees and environmental conservation. Sustenance should focus upon renewable sources of energy; efforts of employees should be acknowledged offering flexible working hours; consumer trust should be built by communicating authentic and accurate information about the product. As developing countries encounter several social and environmental problems, companies must endeavor to build a healthy nation keeping in mind the welfare of all stakeholders by practicing CSR.Originality/valueThis study overcomes the limitations of prior cross-country studies by taking a better representative sample with greater number of countries belonging to identifiable group of “developing” and “developed” nations and thus attempts to improve generalization and authenticity of results.