bluuebunny/crossref_metadata_2025_split huggingface dataset:
Trans-cinnamaldehyde attenuatesEnterococcus faecalisvirulence and inhibits biofilm formation
Authors: Ali Islam A. A. , Matinlinna Jukka P. , Lévesque Celine M. , Neelakantan Prasanna 
Published: March 2021

AbstractEnterococcus faecalisas an important nosocomial pathogen is critically implicated in the pathogenesis of endocarditis, urinary tract and surgical wound infections. Its major virulence attributes (biofilm formation, production of proteases and hemolytic toxins) enable it to cause extensive host tissue damage. With the alarming increase in enterococcal resistance to antibiotics, novel therapeutics are required to inhibitE. faecalisbiofilm formation and virulence.Trans-cinnamaldehyde (TC), the main phytochemical in cinnamon essential oils has demonstrated promising activity against a wide range of pathogens. Here, we comprehensively investigated the effect of TC on planktonic growth, biofilm formation, proteolytic and hemolytic activities, as well as gene regulation inE. faecalis. Our findings revealed that sub-inhibitory concentrations of TC reduced biofilm formation, biofilm exopolysaccharides as well as its proteolytic and hemolytic activities. Mechanistic studies revealed significant down regulation of the quorum sensingfsrlocus and downstreamgelE, which are major virulence regulators inE. faecalis. Taken together, our study highlights the potential of TC to inhibitE. faecalisbiofilm formation and its virulence.
Gα13 loss promotes tumor progression in the KPC transgenic mouse model of advanced pancreatic cancer
Authors: Shields Mario A. , Spaulding Christina , Khalafalla Mahmoud G. , Pham Thao N.D. , Munshi Hidayatullah G. 
Published: March 2021

SUMMARYGα13 transduces signals from G protein-coupled receptors. Gα13 is pro-tumorigenic in epithelial cancer cell lines, which contrasts with its tumor-suppressive function in transgenic mouse models of lymphomas. Here we show that while loss of Gα13 in pancreatic cell lines decreases tumor growthin vivo, Gα13 loss in the Kras-driven (KC) mouse model of pancreatic tumor initiation does not affect tumor development or survival. Instead, Gα13 loss in the Kras/Tp53 (KPC) transgenic mouse model of advanced pancreatic cancer promotes well-differentiated tumors with increased tumor burden and reduced survival. Mechanistically, Gα13 loss in the KPC mouse model enhances E-cadherin-mediated cell-cell junctions and mTOR signaling. Importantly, human pancreatic cancers with low Gα13 expression exhibit increased E-cadherin protein expression and mTOR signaling. This work establishes a context-dependent role of Gα13 in pancreatic tumorigenesis, demonstrating a tumor-suppressive role in transgenic mouse models of advanced pancreatic cancer.
DNA tension-modulated translocation and loop extrusion by SMC complexes revealed by molecular dynamics simulations
Authors: Nomidis Stefanos K. , Carlon Enrico , Gruber Stephan , Marko John F. 
Published: March 2021

ABSTRACTStructural Maintenance of Chromosomes (SMC) complexes play essential roles in genome organization across all domains of life. To determine how the activities of these large ( 50 nm) complexes are controlled by ATP binding and hydrolysis, we developed a molecular dynamics model that accounts for conformational motions of the SMC and DNA. The model combines DNA loop capture with an ATP-induced “power stroke” to translocate the SMC complex along DNA. This process is sensitive to DNA tension: at low tension (0.1 pN), the model makes loop-capture steps of average 60 nm and up to 200 nm along DNA (larger than the complex itself), while at higher tension, a distinct inchworm-like translocation mode appears. By tethering DNA to an experimentally-observed additional binding site (“safety belt”), the model SMC complex can perform loop extrusion (LE). The dependence of LE on DNA tension is distinct for fixed DNA tension vs. when fixed DNA end points: LE reversal occurs above 0.5 pN for fixed tension, while LE stalling without reversal occurs at about 2 pN for fixed end points. Our model matches recent experimental results for condensin and cohesin, and makes testable predictions for how specific structural variations affect SMC function.
Computational Design and Analysis of Modular Cells for Large Libraries of Exchangeable Product Synthesis Modules
Authors: Garcia Sergio , Trinh Cong T. 
Published: March 2021

AbstractMicrobial metabolism can be harnessed to produce a large library of useful chemicals from renewable resources such as plant biomass. However, it is laborious and expensive to create microbial biocatalysts to produce each new product. To tackle this challenge, we have recently developed modular cell (ModCell) design principles that enable rapid generation of production strains by assembling a modular (chassis) cell with exchangeable production modules to achieve overproduction of target molecules. Previous computational ModCell design methods are limited to analyze small libraries of around 20 products. In this study, we developed a new computational method, named ModCell-HPC, capable of designing modular cells for large libraries with hundredths of products with a highly-parallel and multi-objective evolutionary algorithm. We demonstrated ModCell-HPC to designEscherichia colimodular cells towards a library of 161 endogenous production modules. From these simulations, we identifiedE. colimodular cells with few genetic manipulations that can produce dozens of molecules in a growth-coupled manner under different carbons sources. These designs revealed key genetic manipulations at the chassis and module levels to accomplish versatile modular cells. Furthermore, we used ModCell-HPC to identify design features that allow an existing modular cell to be re-purposed towards production of new molecules. Overall, ModCell-HPC is a useful tool towards more efficient and generalizable design of modular cells to help reduce research and development cost in biocatalysis.
Morphological principles of neuronal mitochondria
Authors: Mendelsohn Rachel , Garcia Guadalupe C. , Bartol Thomas M. , Lee Christopher T. , Khandelwal P. , Liu Emily , Spencer Donald J. , Husar Adam , Bushong Eric A. , Phan Sebastien , Perkins Guy , Ellisman Mark H. , Skupin Alexander , Sejnowski Terrence J. , Rangamani Padmini 
Published: March 2021

AbstractIn the highly dynamic metabolic landscape of a neuron, mitochondrial membrane architectures can provide critical insight into the unique energy balance of the cell. Current theoretical calculations of functional outputs like ATP and heat often represent mitochondria as idealized geometries and therefore can miscalculate the metabolic fluxes. To analyze mitochondrial morphology in neurons of mouse cerebellum neuropil, 3D tracings of complete synaptic and axonal mitochondria were constructed using a database of serial TEM tomography images and converted to watertight meshes with minimal distortion of the original microscopy volumes with a granularity of 1.6 nanometer isotropic voxels. The resultingin silicorepresentations were subsequently quantified by differential geometry methods in terms of the mean and Gaussian curvatures, surface areas, volumes, and membrane motifs, all of which can alter the metabolic output of the organelle. Finally, we identify structural motifs that are present across this population of mitochondria; observations which may contribute to future modeling studies of mitochondrial physiology and metabolism in neurons.
Into the woods of corporate fairytales and environmental reporting
Authors: Morrison Leanne J. , Lowe Alan 
Published: March 2021

PurposeUsing a dialogic approach to narrative analysis through the lens of fairytale, this paper explores the shared construction of corporate environmental stories. The analysis provided aims to reveal the narrative messaging which is implicit in corporate reporting, to contrast corporate and stakeholder narratives and to bring attention to the ubiquity of storytelling in corporate communications.Design/methodology/approachThis paper examines a series of events in which a single case company plays the central role. The environmental section of the case company's sustainability report is examined through the lens of fairytale analysis. Next, two counter accounts are constructed which foreground multiple stakeholder accounts and retold as fairytales.FindingsThe dialogic nature of accounts plays a critical role in how stakeholders understand the environmental impacts of a company. Storytelling mechanisms have been used to shape the perspective and sympathies of the report reader in favour of the company. We use these same mechanisms to create two collective counter accounts which display different sympathies.Research limitations/implicationsThis research reveals how the narrative nature of corporate reports may be used to fabricate a particular perspective through storytelling. By doing so, it challenges the authority of the version of events provided by the company and gives voice to collective counter accounts which are shared by and can be disseminated to other stakeholders.Originality/valueThis paper provides a unique perspective to understanding corporate environmental reporting and the stories shared by and with external stakeholders by drawing from a novel link between fairytale, storytelling and counter accounting.
Imprecise abstract argumentation as a support for forensic engineering
Authors: Taillandier Franck , Baudrit Cédric , Carvajal Claudio , Delhomme Benjamin , Beullac Bruno 
Published: March 2021

PurposeCivil engineering structures are regularly confronted with failures that can lead to catastrophic consequences. It is important, after a failure, to be able to identify the origin and the sequence of factors that led to it. This failure analysis by experts, called forensic engineering investigation, generally leads to the drafting of an expert report. These reports do not inform on the processes that guided the experts to a conclusion and the uncertainties involved. This paper aims to propose a new methodological approach to formalize the opinions of experts in forensic engineering.Design/methodology/approachThe research consists in combining abstract argumentation with the theory of imprecise probabilities to take into account epistemic and stochastic uncertainties to support forensic engineering investigation.FindingsA model and a tool to support forensic analysis are presented. An application on the collapse of the Brumadinho dam highlights the interest of the chosen approach.Originality/valueThis work is the first use of the abstract argument framework in civil engineering, and so in forensic engineering. Furthermore, it provides an innovative model based on imprecise probability for AAF.
Revealing industry challenge and business response to Covid-19: a text mining approach
Authors: Yang Mu , Han Chunjia 
Published: March 2021

PurposeThis study aims to conduct a “real-time” investigation with user-generated content on Twitter to reveal industry challenges and business responses to the coronavirus (Covid-19) pandemic. Specifically, using the hospitality industry as an example, the study analyses how Covid-19 has impacted the industry, what are the challenges and how the industry has responded.Design/methodology/approachWith 94,340 tweets collected between October 2019 and May 2020 by a programmed Web scraper, unsupervised machine learning approaches such as structural topic modelling are applied.Originality/valueThis study contributes to the literature on business response during crises providing for the first time a study of using unstructured content on social media for industry-level analysis in the hospitality context.
Stewardship of noncommunicable diseases in Iran: a qualitative study
Authors: Nasiri Taha , Yazdani Shahram , Shams Lida , Takian Amirhossein 
Published: March 2021

PurposeNoncommunicable diseases (NCDs) count for over 80% of premature death worldwide. More than 76% of the total burden of diseases in Iran is devoted to NCDs. In line with the World Health Organization action plan, Iran has developed its national action plan that led to establishment of the National Committee for Prevention and Control of NCDs (INCDC), whose aim is 30% mortality reduction attributed to NCDs by 2030. The stewardship of health system is the cornerstone of performing and sustaining meaningful actions toward prevention and control of NCDs. The literature is tiny on how to materialize the stewardship and governance of health system. The purpose of this article is to report the findings of a national study that aimed to identity functions and subfunctions of stewardship of NCDs and its related risk factors in Iran.Design/methodology/approachThis is a qualitative study. The authors conducted interviews with 18 purposefully selected interviewees until the authors reached saturation. Thematic content analysis was used for analysis and MAXQDA 10 was employed for data management. The difficulty of coordinating with interviewers and health policymakers in the field slowed the process of research progress.FindingsThe authors identified seven themes and categorized them as main functions for appropriate stewardship of NCDs in Iran, including intelligence generation; strategic framework; evidence-based policies/decisions; system design; resource allocation/development; capacity-building and enforcement/alignment; and categorized them as important.Practical implicationsThe seven themes presented as stewardship functions include concepts and practical examples of the experiences and performance of leading countries in the field of NCDs control that can help policymakers and health managers for better descion-making.Originality/valueIran adopted its national action plan in 2015 and WHO selected Iran as a fast-track country in 2017. The study confirmed that to achieve the global targets, appropriate and contextual stewardship for any specific setting is fundamental. Iran needs to improve its stewardship for prevention and control of NCDs and implement its national action plan. Therefore, the functions and policies outlined in this article for the proper performance of NCDs can improve more meaningful practices in this area in Iran and many other countries.
Analysis of public hospital governance reforms: a case from a developing country
Authors: Lipunga Andrew Munthopa , Tchereni Betchani M.H. , Bakuwa Rhoda Cythia 
Published: March 2021

PurposeThe purpose of this paper is to explore the nature of governance reforms also called conceptual innovation for public hospitals in Malawi.Design/methodology/approachIt focuses on the reforms for central and district hospitals. It uses semi-structured interviews to collect data and thematic approach to analyse it.FindingsThe results show that the reforms for central hospitals are structurally well characterised as aimed at corporatisation though they are termed as automatisation. The terminological seems not to pose any harm on the direction of the reforms due to the thorough structural characterisation. On the other hand, reforms for district hospitals are vague as such implementation is retrogressive, in that, instead of progressively moving the hospitals towards greater autonomy the opposite is happening.Originality/valueThe paper highlights the significance of characterisation of the intended outcome on the direction of the reforms and proposes a framework to guide conceptual innovation for public hospitals in a devolution-mediated environment.
Dynamic risk-based optimization on cryptocurrencies
Authors: Nugroho Bayu Adi 
Published: March 2021

PurposeIt is crucial to find a better portfolio optimization strategy, considering the cryptocurrencies' asymmetric volatilities. Hence, this research aimed to present dynamic optimization on minimum variance (MVP), equal risk contribution (ERC) and most diversified portfolio (MDP).Design/methodology/approachThis study applied dynamic covariances from multivariate GARCH(1,1) with Student’s-t-distribution. This research also constructed static optimization from the conventional MVP, ERC and MDP as comparison. Moreover, the optimization involved transaction cost and out-of-sample analysis from the rolling windows method. The sample consisted of ten significant cryptocurrencies.FindingsDynamic optimization enhanced risk-adjusted return. Moreover, dynamic MDP and ERC could win the naïve strategy (1/N) under various estimation windows, and forecast lengths when the transaction cost ranging from 10 bps to 50 bps. The researcher also used another researcher's sample as a robustness test. Findings showed that dynamic optimization (MDP and ERC) outperformed the benchmark.Practical implicationsSophisticated investors may use the dynamic ERC and MDP to optimize cryptocurrencies portfolio.Originality/valueTo the best of the author’s knowledge, this is the first paper that studies the dynamic optimization on MVP, ERC and MDP using DCC and ADCC-GARCH with multivariate-t-distribution and rolling windows method.
Industry ties, entrepreneurs' employment experience and resource acquisition of new ventures in China
Authors: Zhao Wenhong , Zhang Wenwei , Shu Chengli 
Published: March 2021

PurposeSocial network theory emphasizes that, to acquire needed resources, new ventures should cultivate industrial connections (intra-industry ties and extra-industry ties). In the meanwhile human capital theory focuses on entrepreneurs' employment experience, especially with respect to its breadth and depth. This study examines ties and experience to determine whether, in combination, they have positive or negative effects on resource acquisition in new ventures.Design/methodology/approachThis study tests research hypotheses using questionnaire survey data with a sample of entrepreneurs in new ventures. Multivariate regression analysis is used to analyze the data.FindingsCombining intra-industry ties and experience breadth or extra-industry ties and experience depth affects resource acquisition positively, whereas combining intra-industry ties and experience depth or extra-industry ties and experience breadth affects resource acquisition negatively.Research limitations/implicationsConclusions may be constrained by the limited sample size and source. Rather, the impact of the study lies in its identification of the effects of interaction between network ties and entrepreneurs' experience on resource acquisition. Future research can explore the effects of interaction between other dimensions of network ties and a range of entrepreneurs' experience characteristics on resource acquisition.Practical implicationsEntrepreneurs are provided with effective strategies to make use of their ventures' network ties and their personal accumulated experience in the process of obtaining resources.Originality/valueThe findings enrich the entrepreneurship literature by providing a more nuanced understanding of how and when new ventures' industry ties and entrepreneurs' employment experience together influence resource acquisition.
Trans‐generational viral transmission and immune priming are dose‐dependent
Authors: Wilson Kenneth , Grzywacz David , Cory Jenny S. , Donkersley Philip , Graham Robert I. 
Published: March 2021

Abstract

It is becoming increasingly apparent that trans‐generational immune priming (i.e. the transfer of the parental immunological experience to its progeny resulting in offspring protection from pathogens that persist across generations) is a common phenomenon not only in vertebrates, but also invertebrates. Likewise, it is known that covert pathogenic infections may become ‘triggered’ into an overt infection by various stimuli, including exposure to heterologous infections. Yet, rarely have both phenomena been explored in parallel.

Using as a model system the African armyworm Spodoptera exempta, an eruptive agricultural pest and its endemic dsDNA virus (Spodoptera exempta nucleopolyhedrovirus, SpexNPV), the aim of this study was to explore the impact of parental inoculating‐dose on trans‐generational pathogen transmission and immune priming (in its broadest sense).

Larvae were orally challenged with one of five doses of SpexNPV and survivors from these treatments were mated and their offspring monitored for viral mortality. Offspring from parents challenged with low viral doses showed evidence of ‘immune priming’ (i.e. enhanced survival following SpexNPV challenge); in contrast, offspring from parents challenged with higher viral doses exhibited greater susceptibility to viral challenge.

Most offspring larvae died of the virus they were orally challenged with; in contrast, most offspring from parents that had been challenged with the highest doses were killed by the vertically transmitted virus (90%) and not the challenge virus.

These results demonstrate that the outcome of a potentially lethal virus challenge is critically dependent on the level of exposure to virus in the parental generation—either increasing resistance at very low parental viral doses (consistent with trans‐generational immune priming) or increasing susceptibility at higher parental doses (consistent with virus triggering).

We discuss the implications of these findings for understanding both natural epizootics of baculoviruses and for using them as biological control agents.
Fitness consequences of longer breeding seasons of a migratory passerine under changing climatic conditions
Authors: Halupka Lucyna , Borowiec Marta , Neubauer Grzegorz , Halupka Konrad 
Published: March 2021

AbstractNumerous studies have shown that climate change affects the timing of migration and bird laying dates, but the resulting changes in the duration of breeding seasons and their fitness consequences remain largely unknown.We compared breeding parameters of 343 individually marked female Eurasian reed warblers, a multi‐brooded migratory passerine, studied in the same area in 1980–1983 and 2005–2012. The latter period was warmer, with mean temperatures during the breeding season higher by 1.5°C on average. As, in recent years, birds arrive earlier from wintering areas and the breeding season of the population is longer, we hypothesized it should result in the increased re‐nesting opportunities of individual females.We found that breeding periods of individual females (from building of the first nest till the end of caring for last fledglings/last nest failure) in the current century have extended by 2 weeks compared to the 1980s. In the 2000s, females produced 75% more fledglings annually than females in the 1980s (2.8 vs. 1.6, respectively). The proportion of females raising second broods increased from 2.7% to 23.6% between the first and the second study period while the share of females that did not produce any young annually decreased from 48.1% to 15.5%. The higher offspring production in recent years was related to more successfully fledged broods and an earlier start of breeding, which secured more time to re‐nest.Higher female parental effort in recent years was not manifested in the reduction of the female apparent survival: it was almost identical in the two study periods (0.30 vs. 0.31).We conclude that prolonged reproductive seasons might be beneficial for some species. Identifying causes and consequences of changes in the duration of breeding seasons may be essential to predict demography of populations under changing climatic conditions.