bluuebunny/crossref_metadata_2025_split huggingface dataset:
Protein Arginine Deiminase 4 Antagonizes Methylglyoxal-induced Histone Glycation
Authors: Zheng Qingfei , Osunsade Adewola , David Yael 
Published: November 2019

AbstractProtein arginine deiminase 4 (PAD4) facilitates the post-translational citrullination of the core histones H3 and H4. While the precise epigenetic function of this modification has not been resolved, it was shown to associate with general chromatin decompaction and to compete with arginine methylation. Recently, we showed that histones are subjected to methylglyoxal (MGO)-induced glycation on nucleophilic side chains, particularly arginines, under metabolic stress conditions. These non-enzymatic adducts change chromatin architecture and the epigenetic landscape by competing with enzymatic modifications. Here we report that PAD4 antagonizes histone MGO-glycation by protecting the reactive sites with oxygen substitution, as well as by converting already-glycated arginine residues into citrulline. Moreover, we show that similar to the deglycase DJ-1, PAD4 is overexpressed and histone citrullination is upregulated in breast cancer tumors, suggesting an additional mechanistic link to PAD4’s oncogenic properties.SignificanceMetabolic syndromes and diabetes increase the risk for certain diseases such as cancer. However, the mechanism behind this correlation is poorly understood. Methylglyoxal (MGO), a reactive dicarbonyl sugar metabolite found in cells under metabolic stress, can non-enzymatically modify arginine and lysine residues in histone proteins, making it a new epigenetic marker linking metabolism and disease. Histone MGO-glycation induces changes in chromatin architecture and the epigenetic landscape, and abrogates gene transcription. In this study, we found that protein arginine deiminase 4 (PAD4) exhibits dual functions to antagonize histone MGO-glycation: removing glycation adducts from arginines and converting the unmodified side chains into citrulline, which protects them from undergoing glycation. This unprecedented biochemical mechanism demonstrates a potential function of PAD4 in cancer cells.
Secondary metabolism in the gill microbiota of shipworms (Teredinidae) as revealed by comparison of metagenomes and nearly complete symbiont genomes
Authors: Altamia Marvin A. , Lin Zhenjian , Trindade-Silva Amaro E. , Uy Iris Diana , Shipway J. Reuben , Wilke Diego Veras , Concepcion Gisela P. , Distel Daniel L. , Schmidt Eric W. , Haygood Margo G. 
Published: November 2019

AbstractShipworms play critical roles in recycling wood in the sea. Symbiotic bacteria supply enzymes that the organisms need for nutrition and wood degradation. Some of these bacteria have been grown in pure culture and have the capacity to make many secondary metabolites. However, little is known about whether such secondary metabolite pathways are represented in the symbiont communities within their hosts. In addition, little has been reported about the patterns of host-symbiont co-occurrence. Here, we collected shipworms from the United States, the Philippines, and Brazil, and cultivated symbiotic bacteria from their gills. We analyzed sequences from 22 shipworm gill metagenomes from seven shipworm species and from 23 cultivated symbiont isolates. Using (meta)genome sequencing, we demonstrate that the cultivated isolates represent all the major bacterial symbiont species and strains in shipworm gills. We show that the bacterial symbionts are distributed among shipworm hosts in consistent, predictable patterns. The symbiotic bacteria encode many biosynthetic gene cluster families (GCFs) for bioactive secondary metabolites, only <5% of which match previously described biosynthetic pathways. Because we were able to cultivate the symbionts, and sequence their genomes, we can definitively enumerate the biosynthetic pathways in these symbiont communities, showing that ∼150 out of ∼200 total biosynthetic gene clusters (BGCs) present in the animal gill metagenomes are represented in our culture collection. Shipworm symbionts occur in suites that differ predictably across a wide taxonomic and geographic range of host species, and collectively constitute an immense resource for the discovery of new biosynthetic pathways to bioactive secondary metabolites.ImportanceWe define a system in which the major symbionts that are important to host biology and to the production of secondary metabolites can be cultivated. We show that symbiotic bacteria that are critical to host nutrition and lifestyle also have an immense capacity to produce a multitude of diverse and likely novel bioactive secondary metabolites that could lead to the discovery of drugs, and that these pathways are found within shipworm gills. We propose that, by shaping associated microbial communities within the host, the compounds support the ability of shipworms to degrade wood in marine environments. Because these symbionts can be cultivated and genetically manipulated, they provide a powerful model for understanding how secondary metabolism impacts microbial symbiosis.
Correction of missing-wedge artifacts in filamentous tomograms by template-based constrained deconvolution
Authors: Kovacs Julio , Song Jun Ha , Auer Manfred , He Jing , Wriggers Willy 
Published: November 2019

AbstractCryo-electron tomography maps often exhibit considerable noise and anisotropic resolution, due to the low-dose requirements and the missing wedge in Fourier space. These spurious features are visually unappealing and, more importantly, prevent an automated segmentation of geometric shapes, requiring a highly subjective, labor-intensive manual tracing. We developed a novel computational strategy for objectively denoising and correcting missing-wedge artifacts in the special but important case of repetitive basic shapes, such as filamentous structures. In this approach, we use the template and a non-negative “location map” to constrain the deconvolution scheme, allowing us to recover, to a considerable degree, the information lost in the missing wedge. We applied our method to data of actin-filament bundles of inner-ear stereocilia, which are critical in hearing transduction processes, and found a good overlap with the experimental map and with manual tracing. In addition, we demonstrate that our method can also be used for membrane detection.
Entorhinal and ventromedial prefrontal cortices abstract and generalise the structure of reinforcement learning problems
Authors: Baram Alon B , Muller Timothy H , Nili Hamed , Garvert Mona , Behrens Timothy E J 
Published: November 2019

AbstractKnowledge of the structure of a problem, such as relationships between stimuli, enables rapid learning and flexible inference. Humans and other animals can abstract this structural knowledge and generalise it to solve new problems. For example, in spatial reasoning, shortest-path inferences are immediate in new environments. Spatial structural transfer is mediated by grid cells in entorhinal and (in humans) medial prefrontal cortices, which maintain their structure across different environments. Here, using fMRI, we show that entorhinal and ventromedial prefrontal cortex (vmPFC) representations perform a much broader role in generalising the structure of problems. We introduce a task-remapping paradigm, where subjects solve multiple reinforcement learning (RL) problems differing in structural or sensory properties. We show that, as with space, entorhinal representations are preserved across different RL problems only if task structure is preserved. In vmPFC, representations of standard RL signals such as prediction error also vary as a function of task structure.
Regulation of apical constriction via microtubule- and Rab11-dependent apical transport during tissue invagination
Authors: Le Thao Phuong , Chung SeYeon 
Published: November 2019

AbstractThe formation of an epithelial tube is a fundamental process for organogenesis. DuringDrosophilaembryonic salivary gland (SG) invagination, Folded gastrulation (Fog)- dependent Rho-associated kinase (Rok) promotes contractile apical myosin formation to drive apical constriction. Microtubules (MTs) are also crucial for this process and are required for forming and maintaining apicomedial myosin. However, the underlying mechanism that coordinates actomyosin and MT networks still remains elusive. Here, we show that MT-dependent intracellular trafficking regulates apical constriction during SG invagination. Key components involved in protein trafficking, such as Rab11 and Nuclear fallout (Nuf), are apically enriched near the SG invagination pit in a MT-dependent manner. Disruption of the MT networks or knockdown ofRab11impairs apicomedial myosin formation and apical constriction. We show that MTs and Rab11 are required for apical enrichment of the Fog ligand and the continuous distribution of the apical determinant protein Crumbs (Crb) and the key adherens junction protein E-Cadherin (E-Cad) along junctions. Targeted knockdown ofcrborE-Cadin the SG disrupts apical myosin networks and results in apical constriction defects. Our data suggest a role of MT- and Rab11-dependent intracellular trafficking in regulating actomyosin networks and cell junctions, to coordinate cell behaviors during tubular organ formation.
Sleep promotes downward firing rate homeostasis
Authors: Pacheco Alejandro Torrado , Bottorff Juliet , Turrigiano Gina G. 
Published: November 2019

SUMMARYHomeostatic plasticity is hypothesized to regulate neuronal activity around a stable set point to compensate for learning-related plasticity. This regulation is predicted to be bidirectional but only upward firing rate homeostasis (FRH) has been demonstrated in vivo. We combined chronic electrophysiology in freely behaving animals with a protocol that induces robust plasticity in primary visual cortex (V1) to induce downward FRH and show that neurons bidirectionally regulate firing rates around an individual set point. Downward FRH did not require N-methyl-D-aspartate receptor (NMDAR) signaling and was associated with homeostatic scaling down of synaptic strengths. Like upward FRH, downward FRH was gated by vigilance state, but in the opposite direction: it occurred during sleep and not during wake. In contrast, FR changes associated with Hebbian plasticity happened independently of sleep and wake. Thus, we find that sleep’s impact on neuronal plasticity depends on the particular forms of plasticity that are engaged.
The utilisation of library spaces by postgraduate students at a university in an African country
Authors: Bangani Siviwe , Moyo Mathew , Mashiyane Dina Mokgadi 
Published: November 2019

Purpose
The purpose of this paper is to determine the use of library spaces by postgraduate students at the North-West University in South Africa.

Design/methodology/approach
A survey research methodology was used in which both online and print questionnaires were used to gather data.

Findings
The major findings of the study were that postgraduate students frequently visited the libraries to make use of the quite study spaces, which include the research commons and the study carrels. The study further found out that postgraduate students rarely visited the libraries for the purpose of consulting librarians regarding their studies. Challenges expressed by the students include insufficient workstations, poor internet and Wi-Fi connectivity and limited seating capacity. The benefit of the study is that it will help librarians and the university administrators to better understand the postgraduate students space needs, as well as the challenges being encountered.

Research limitations/implications
This biggest limitation of this study was a lack or low response rate by certain faculties, which mitigated against comparing the use of spaces by faculty.

Practical implications
The results of this study re-affirm the need for postgraduate spaces. University libraries that seek to build postgraduate spaces in the future need to ensure that an adequate number of computer workstations are supplied and Wi-Fi and bandwidth are improved. University libraries that already have postgraduate spaces should consider adding more workstations and improving bandwidth and Wi-Fi connectivity in those spaces. These results further point to a need for libraries in Africa and elsewhere to consider having more quiet study spaces for postgraduate students while reducing the number of group study spaces.

Social implications
The results of this study point to a need for libraries and university authorities to periodically review library spaces as a way to ensure their continued optimal usage. They also point to a need for more funds to further enhance the library spaces for postgraduate students’ use.

Originality/value
South African libraries are faced with challenges including the addition of 15 per cent value added tax to print and online resources. In this environment, libraries are expected by university authorities to demonstrate return on investment. This study, therefore, is located within the realm of determining return on investment for the funds spent by universities to build dedicated postgraduate library spaces. This study will further benefit librarians and the university administrators by helping them to better understand the postgraduate students space needs, as well as the challenges being encountered.
Structural change and technical efficiency: a study of Indian pulp and paper industry
Authors: Kathuria Vinish 
Published: November 2019

Purpose
The pulp and paper industry has been the focus of government policies ever since independence. This is the only industry where government plays a multi-dimensional role – not only as the regulator but also as the supplier of raw material and as the buyer. Despite the government's omnipotent role, there is evidence that industry is not very competitive, as it has very high energy and water intensity and poor productivity. A potent factor identified in the literature for the underperformance of the industry or for that matter any economy is the kind of technology used by the firms in the sector. This paper aims to look into the role of government policy in affecting the growth of the industry and what role embodied technology has played in influencing the efficiency of firms in Indian pulp and paper industry.

Design/methodology/approach
For the first question, the study uses 66 years of production data of the industry from 1951 to 2016 and tests for the structural break. For the second question, the study uses cross-section plant-level data for the year 2011-2012 of 160 paper manufacturing units to first estimate the stochastic production frontier (stochastic frontier analysis [SFA]) and then uses the output of SFA to find an association between embodied technology gap (TG) and technical efficiency. A methodological problem in earlier literature is the use of the productivity gap as a proxy for embodied TG. The present study uses technical parameters of papermaking – machine deckle and operating speed – to construct an index of TG.

Findings
The results show a structural break in the production trend occurring in 1999 with the delicensing in July 1997 as the possible cause. The SFA results show that the average technical inefficiency (TE) of the firms in the sector is 74 per cent with half of the firms having TE higher than 76 per cent. The study, however, does not find any impact of embodied TG on technical efficiency; rather it is the age, size, ownership and location that have an impact on it.

Originality/value
This is an original research, as the author has not come across any study in Indian context or elsewhere using technical parameters to construct TG variable.
One Belt One Road: will it increase the gravity between China and Eurasia
Authors: Rahman Nida , Rahman Mohd Nayyer 
Published: November 2019

Purpose
Globalisation has remained a subjective term as the magnitude unfolded. Every new decade witnesses new opportunities for global integration of the economies. One among such initiatives, it is argued, is the One Belt One Road initiative of the People’s Republic of China. It is assumed to be beneficial for the world and at least for the region, if not to say more. The world has witnessed efforts and trends of protectionism as well, but China comes up with new vigour. One Belt One Road has entered into consistent talks and deliberations at the world level. It is therefore imperative to identify the emerging linkages between the participant countries in One Belt One Road. This study aims to take up the task of enquiring about the effect of One Belt One Road on the gravity between China and the nations of Eurasia. This study looks for the realisation of the expected economic ties and internationalisation emerging from One Belt One Road and the evidence for the same. This will be identified in the present study. The paper also attempts to theorise a model for One Belt One Road.

Design/methodology/approach
This study takes up the task of enquiring about the effect of One Belt One Road on the gravity between China and the nations of Eurasia. The hypothesised economic ties and internationalisation will be a reality or not. And what are the evidences for the same. This will be identified in the proposed study. An attempt to theorise the model for One Belt One Road is also taken.

Findings
It is perceived that the mega project would fill the wedge between China and Eurasia and convergence will follow with the start of the One Belt One Road.

Originality/value
The emergence of China in the global world order as the initiator of mega deals and projects and its dominion in every realm of economic activity is a topic of scrutiny for the entire world. In this context, the One Belt One Road initiative offers huge potential for exploration. As the project is in its early stages of planning and execution, its prospects of tying entire Europe and Russia with China through two of the revived ancient routes are essential to the entire world.
Can employees perform well if they fear for their lives? Yes – if they have a passion for work
Authors: Haq Inam Ul , De Clercq Dirk , Azeem Muhammad Umer 
Published: November 2019

PurposeWith a basis in conservation of resources theory, the purpose of this paper is to investigate the mediating role of championing behaviour in the relationship between employees’ fear of terror and their job performance, as well as the buffering role of their passion for work, as a personal resource, in this process.Design/methodology/approachThe tests of the hypotheses rely on three-wave, time-lagged data collected from employees and their supervisors in Pakistan.FindingsAn important reason that concerns about terrorist attacks diminish performance is that employees refrain from championing their own entrepreneurial ideas. This mediating role of idea championing is less salient, however, to the extent that employees feel a strong passion for their work.Practical implicationsFor human resource managers, this study pinpoints a key mechanism – a reluctance to mobilize active support for entrepreneurial ideas – by which fears about terrorism attacks can spill over into the workplace and undermine employees’ ability to meet their performance requirements. It also reveals how this mechanism can be better contained by the presence of adequate personal resources.Originality/valueThis study adds to burgeoning research on the interplay between terrorism and organizational life by specifying how and when employees’ ruminations about terrorism threats might escalate into diminished performance outcomes at work.
Investment funds and underpricing of shares
Authors: Castilho Hitalo Alberto de Souza Faria , Resende Matheus Souza De , Montoro Eduardo Ramos de Oliveira Franco , Shotoko Vinicius Akio De Almeida , Jucá Michele Nascimento , Junior Eli Hadad 
Published: November 2019

Purpose
The purpose of this paper is to assess whether greater participation of venture capital/private equity (VC/PE) funds in the companies’ capital structure at the moment of initial public offering (IPO) contributes to the reduction in the underpricing of their shares.

Design/methodology/approach
Descriptive statistics, correlation analysis, mean difference test and cross-sectional regression were used. The final sample consisted of 89 companies making IPO in Brasil Bolsa Balcão between 2007 and 2017.

Findings
The participation of VC/PE funds was shown to mitigate the effect of information asymmetry on managers and shareholders, thus reducing the underpricing of companies at the moment of IPO (H1). However, the expectation that a greater participation of these funds promotes further reduction in a potential underpricing (H2) was not confirmed.

Research limitations/implications
One can highlight the small amount of IPOs during the sampling period due to the occurrence of international and national economic crises, as well as the difficulty in obtaining information on the participation of VC/PE funds in the companies’ capital structure.

Practical implications
It was observed that information asymmetry had a mitigating effect from the presence of these funds in the companies, which can improve the pricing of their shares, decrease the costs and make volume captions viable for investments, in addition to giving credibility to the market information effectiveness.

Originality/value
This study differs from others in that it assesses not only the influence of VC/PE funds on the reduction of the underpricing of IPO shares, but also the participation of these funds in the capital of these companies.
The relationship between TQM practices and organisational innovation outcomes
Authors: Abu Salim Taghreed , Sundarakani Balan , Lasrado Flevy 
Published: November 2019

PurposeThe purpose of this paper is to study the role of slack (both moderating and mediating) to stimulate the relationship between total quality management (TQM) factors and innovation outcomes relative to gaining competitive industry advantages.Design/methodology/approachThe research methodology includes a multi-item scale questionnaire completed in three waves between 2016 and 2017, and later analysed in 2018. A final response rate of 29.5 per cent was obtained, representing 190 organisations from both manufacturing and service industries in the United Arab Emirates (UAE). Partial least squares structural equation modelling was used to test the multi-collinearity, moderation and mediation analysis.FindingsAnalysis confirmed that factors such as continuous improvement (CI), human resource management (HRM) and information measurement (IM) were positively linked to innovation. However, when slack was introduced as a moderator, innovation outcomes were stimulated through HRM and IM. The results indicate that slack acts as a full mediator for management leadership but only partially mediates supplier quality, IM, CI, HRM and process management.Research limitations/implicationsIn terms of geographical coverage, research was limited to the UAE. Organisations striving for excellence through innovation may benefit from the outcomes, as they help in understanding the relationship between TQM and innovation moderated and/or mediated by slack. This could also lead businesses to develop new strategies that harmonise TQM policies with “rationale” slack policies, thus, promoting innovation.Originality/valueThis study is the first to examine the use of slack to stimulate the relationship between TQM factors and innovation outcomes. Using slack as a mediator can help in understanding when TQM might influence innovation, while slack as a moderator could invert the relationship between the two.