bluuebunny/crossref_metadata_2025_split huggingface dataset:
Occupational challenges of health care workers during the COVID-19 pandemic. A qualitative study
Authors: Jeleff Maren , Traugott Marianna , Jirovsky-Platter Elena , Jordakieva Galateja , Kutalek Ruth 
Published: May 2021

AbstractBackgroundThe COVID-19 pandemic has placed a significant burden on health care systems worldwide with health care workers (HCWs) delivering care under unprecedented conditions. This study deals with HCWs’ physical, mental, emotional and professional challenges of working during the COVID-19 pandemic and seeks to understand structural determinants of those challenges.MethodsWe carried out an exploratory qualitative study in public and private hospitals in Vienna, Austria. HCWs such as medical doctors, qualified nursing staff, nurse assistants, technical and cleaning staff in direct and indirect contact with COVID-19 patients were included. Collected data was analyzed using content analysis.FindingsWe conducted 30 semi-structured interviews in person and per phone from June 2020 to January 2021. Three overall themes resulted as relevant: challenges due to lack of preparedness, structural conditions, and physical and mental health of HCWs. Lack of preparedness included missing or delayed infection prevention and control (IPC) guidelines, shortages of personal protective equipment (PPE) combined with structural conditions such as staff shortages and overworked personnel. Physical and mental strains resulted from being overworked and working permanently on alert. Further, working in PPE, facing medical uncertainties and the critical conditions of patients were challenging factors. HCWs lacked recognition on multiple levels and dealt with social stigma and avoidance behavior of colleagues, especially in the beginning of the pandemic.InterpretationTo mitigate HCWs’ occupational health risks and staff turnover, we propose the following context-specific recommendations: Required medical personnel in care of COVID-19 patients, especially nursing staff, should be carefully planned and increased to avert chronic work overload. Intensive training and education in palliative care, as well as in IPC for all HCWs is important. Providing supportive supervision is as essential as appropriate recognition by higher level management and the public.FundingThis article has received funding from The Vienna Science and Technology Fund (WWTF) COVID-19 Rapid Response Funding 2020. The funders did not play a role in the decision to publish the article.
Biofilm self-patterning: mechanical forces drive a reorientation cascade
Authors: Nijjer Japinder , Li Changhao , Zhang Qiuting , Lu Haoran , Zhang Sulin , Yan Jing 
Published: May 2021

AbstractIn growing active matter systems, a large collection of engineered or living autonomous units metabolize free energy and create order at different length scales as they proliferate and migrate collectively. One such example is bacterial biofilms, which are surface-attached aggregates of bacterial cells embedded in an extracellular matrix. However, how bacterial growth coordinates with cell-surface interactions to create distinctive, long-range order in biofilms remains elusive. Here we report a collective cell reorientation cascade in growingVibrio choleraebiofilms, leading to a differentially ordered, spatiotemporally coupled core-rim structure reminiscent of a blooming aster. Cell verticalization in the core generates differential growth that drives radial alignment of the cells in the rim, while the radially aligned rim in turn generates compressive stresses that expand the verticalized core. Such self-patterning disappears in adhesion-less mutants but can be restored through opto-manipulation of growth. Agent-based simulations and two-phase active nematic modeling reveal the strong interdependence of the driving forces for the differential ordering. Our findings provide insight into the collective cell patterning in bacterial communities and engineering of phenotypes and functions of living active matter.
Implicit Laplacian of Enhanced Edge: An Unguided Algorithm for Accurate and Automated Quantitative Analysis of Cytoskeletal Images
Authors: Li Pai , Zhang Ze , Tong Yiying , Foda Bardees M. , Day Brad 
Published: May 2021

AbstractThe eukaryotic cytoskeleton plays essential roles in cell signaling and trafficking, which is broadly associated with immunity and diseases of human and plants. To date, most analyses aiming at defining the temporal and spatial dynamics of the cytoskeleton have relied on qualitative and quantitative analysis of fluorescence images to describe cytoskeletal function. While state-of-the-art, these approaches have limitations: the diverse shape and brightness of the cytoskeleton cause considerable inaccuracy in both human-driven and automated approaches, and the widely adopted image projection process (3D to 2D) leads to bias and information loss. Here, we describe the development and application of Implicit Laplacian of Enhanced Edge (ILEE), an unguided approach that uses a 2D/3D-compatible local thresholding algorithm for the quantitative evaluation of cytoskeletal status and organization at high performance. Using ILEE, we constructed a Python library to enable automated cytoskeletal image analysis, providing numerous biologically-interpretable indices measuring the density, bundling, severing, branching, and directionality of the cytoskeleton. The data presented herein demonstrate that ILEE resolves the defects of classic cytoskeleton analysis approaches, enables the measurement of novel cytoskeletal features, and yields quantitatively descriptive data with superior accuracy, stability, and robustness. We released the ILEE algorithm as an open-source library and further developed a Google Colab interface as a community resource.
Structural basis for cell-type specific evolution of viral fitness by SARS-CoV-2
Authors: Gupta Kapil , Toelzer Christine , Williamson Maia Kavanagh , Shoemark Deborah K. , Oliveira A. Sofia F. , Matthews David A. , Almuqrin Abdulaziz , Staufer Oskar , Yadav Sathish K.N. , Borucu Ufuk , Garzoni Frederic , Fitzgerald Daniel , Spatz Joachim , Mulholland Adrian J. , Davidson Andrew D. , Schaffitzel Christiane , Berger Imre 
Published: May 2021

AbstractAs the global burden of SARS-CoV-2 infections escalates, so does the evolution of viral variants which is of particular concern due to their potential for increased transmissibility and pathology. In addition to this entrenched variant diversity in circulation, RNA viruses can also display genetic diversity within single infected hosts with co-existing viral variants evolving differently in distinct cell types. The BriSΔ variant, originally identified as a viral subpopulation by passaging SARS-CoV-2 isolate hCoV-19/England/02/2020, comprises in the spike glycoprotein an eight amino-acid deletion encompassing the furin recognition motif and S1/S2 cleavage site. Here, we elucidate the structure, function and molecular dynamics of this variant spike providing mechanistic insight into how the deletion correlates to viral cell tropism, ACE2 receptor binding and infectivity of this SARS-CoV-2 variant. Moreover, our study reveals long-range allosteric communication between functional regions within the spike that differ in wild-type and deletion variant. Our results support a view of SARS-CoV-2 probing multiple evolutionary trajectories in distinct cell types within the same infected host.
Distinct interhemispheric connectivity at the level of the olfactory bulb emerges during Xenopus laevis metamorphosis
Authors: Weiss Lukas , Arias Paola Segoviano , Offner Thomas , Hawkins Sara Joy , Hassenklöver Thomas , Manzini Ivan 
Published: May 2021

AbstractThe olfactory system of anuran tadpoles requires substantial restructuring to adapt to the lifestyle of the adult frogs. Xenopus laevis tadpoles have a single main olfactory epithelium in the principal nasal cavity associated with aquatic olfaction. After metamorphosis, this epithelial surface is transformed into the adult air-nose and a new epithelium, the adult water-nose, is present in the middle cavity. Impacts of this massive remodeling on odor processing, behavior and network structure are still unexplored.In the present study, we used neuronal tracings, calcium imaging and a behavioral assay to examine the functional connectivity between the epithelium and the main olfactory bulb during metamorphosis. In tadpoles, olfactory receptor neurons in the principal cavity epithelium project axons to glomeruli in the ventral main olfactory bulb. During metamorphosis, these projections are gradually replaced by receptor neuron axons emerging from the newly forming middle cavity epithelium. Despite this metamorphotic reorganization in the ventral bulb, two spatially and functionally segregated odor processing streams remain undisrupted. In line with this, metamorphotic rewiring does not alter behavioral responses to waterborne odorants. Contemporaneously, newly formed receptor neurons in the remodeling principal cavity epithelium project their axons to the dorsal part of the bulb. The emerging neuronal networks of the dorsal and ventral main olfactory bulb show substantial differences. Glomeruli around the midline of the dorsal bulb are innervated from the left and right nasal epithelia. In addition, postsynaptic projection neurons in the dorsal bulb predominantly have smaller tufts and connect to multiple glomeruli, while more than half of projection neurons in the ventral bulb have a single, bigger tuft.Our results show that during the metamorphotic reconstruction of the olfactory network the ‘water system’ remains functional. Differences of the neuronal network of the dorsal and ventral olfactory bulb imply that a higher degree of odor integration takes place in the dorsal main olfactory bulb. This is likely connected with the processing of different odorants, airborne vs. waterborne, in these two parts of the olfactory bulb.
Gut microbiota features associated withClostridioides difficilecolonization in dairy calves
Authors: Redding Laurel E. , Berry Alexander S. , Indugu Nagaraju , Huang Elizabeth , Beiting Daniel P. , Pitta Dipti 
Published: May 2021

AbstractDiarrheal disease, a major cause of morbidity and mortality in dairy calves, is strongly associated with the health and composition of the gut microbiome.Clostridioides difficileis an opportunistic pathogen that proliferates and can produce enterotoxins when the host experiences gut dysbiosis. However, even asymptomatic colonization withC. difficilecan be associated with differing degrees of microbiome disruption in a range of species, including people, swine, and dogs. Little is known about the interaction betweenC. difficileand the gut microbiome in dairy calves. In this study, we sought to define microbial features associated withC. difficilecolonization in pre-weaned dairy calves less than 2 weeks of age. We characterized the fecal microbiota of 80 calves from 23 different farms using 16S rRNA sequencing and compared the microbiota ofC. difficile-positive (n=24) andC. difficile-negative calves (n=56). Farm appeared to be the greatest source of variability in the gut microbiota. When controlling for calf age, diet, and farm location, there was no significant difference in Shannon alpha diversity (P= 0.50) or in weighted UniFrac beta diversity (P=0.19) betweenC. difficile-positive and –negative calves. However, there was a significant difference in beta diversity as assessed using Bray-Curtiss diversity (P=0.0077), andC. difficile-positive calves had significantly increased levels ofRuminococcus (gnavus group)(Adj. P=0.052), Lachnoclostridium(Adj. P=0.060), Butyricicoccus(Adj. P=0.060), andClostridium sensu stricto 2compared toC. difficile-negative calves. Additionally,C. difficile-positive calves had fewer microbial co-occurrences thanC. difficile–negative calves, indicating reduced bacterial synergies. Thus, whileC. difficilecolonization alone is not associated with dysbiosis and is therefore unlikely to result in an increased likelihood of diarrhea in dairy calves, it may be associated with a more disrupted microbiota.
The pitfalls of using Gaussian Process Regression for normative modeling
Authors: Xu Bohan , Kuplicki Rayus , Sen Sandip , Paulus Martin P. 
Published: May 2021

AbstractNormative modeling, a group of methods used to quantify an individual’s deviation from some expected trajectory relative to observed variability around that trajectory, has been used to characterize subject heterogeneity. Gaussian Processes Regression includes an estimate of variable uncertainty across the input domain, which at face value makes it an attractive method to normalize the cohort heterogeneity where the deviation between predicted value and true observation is divided by the derived uncertainty directly from Gaussian Processes Regression. However, we show that the uncertainty directly from Gaussian Processes Regression is irrelevant to the cohort heterogeneity in general.
Termites have developed wider thermal limits to cope with environmental conditions in savannas
Authors: Woon Joel S. , Atkinson David , Adu-Bredu Stephen , Eggleton Paul , Parr Catherine L. 
Published: May 2021

AbstractThe most diverse and abundant family of termites, the Termitidae, evolved in warm, wet African tropical forests. Since then, they have colonised grassy biomes such as savannas. These environments have more extreme temperatures than tropical forests, and greater temporal fluctuations (both annually and diurnally) that are challenging for soft-bodied ectotherms. We propose that that a likely mechanism that facilitated the expansion from forest to savanna was the widening of physiological limits of savanna termite species in order to cope with more extreme environmental conditions. We sampled termites directly from mound structures across an environmental gradient in Ghana, and recorded the thermal tolerance of individual termites, both critical thermal maximum (CTmax) and critical thermal minimum (CTmin). We estimated colony thermal tolerance by taking an average of each tested individual, and modelled these data against several environmental factors (canopy cover above the mound, rainfall and temperature). We found that savanna termite species had significantly higher CTmaxvalues, and significantly lower CTminvalues, than forest species. In addition, areas with high canopy cover were significantly associated with low CTmaxvalues, and areas with higher average daily rainfall were significantly associated with higher CTminvalues. Our results suggest that the widening of thermal tolerances has occurred in savanna termite species, probably in response to the more extreme temperatures found in those environments.
Antimicrobial Effects of Ibuprofen Combined with Standard of Care Antimicrobials against Cystic Fibrosis Pathogens
Authors: Chen Qingquan , Ilanga Marleini , Simbassa Sabona B. , Chirra Bhagath , Shah Kush N. , Cannon Carolyn L. 
Published: May 2021

AbstractCystic Fibrosis (CF) is a common fatal genetic disease caused by mutations happened to cystic fibrosis transmembrane conductance regulator (CFTR) gene. Lungs of CF patients are often colonized or infected with microorganisms. Drug resistant bacterial infection has been problematic in cystic fibrosis patient. The chronic bacterial infections and concomitant airway inflammation could damage the lung and lead to respiratory failure. Several clinical trials have demonstrated that high-dose ibuprofen reduces the rate of pulmonary function decline in CF patients. This beneficial effect has been attributed to the anti-inflammatory properties of ibuprofen. Previously, we have confirmed that high-dose ibuprofen demonstrated antimicrobial activity against P. aeruginosa in in vitro and in vivo. However, no study has examined the antimicrobial effect of combining ibuprofen with standard-of-care (SoC) antimicrobials. Here, we evaluated possible synergistic activity of combinations of common nonsteroidal anti-inflammatory drugs (NSAIDs), namely, aspirin, naproxen, and ibuprofen, with commonly used antibiotics for CF patients. The drug combinations were screened against different CF clinical isolates. Drugs that demonstrated efficacy in the presence of ibuprofen were further verified synergistic effects between these antimicrobials and NSAIDs. Finally, the survival analysis of an P. aeruginosa murine infection model was used to demonstrate the efficacy of synergistic combination. Our results suggest that combinations of ibuprofen with commonly used antibiotics demonstrate synergistic antimicrobial activity against drug resistant, clinical bacterial strains in in vitro. The efficacy of combination ceftazidime and ibuprofen was demonstrated in in vivo.
PIP2-dependent coupling of voltage sensor and pore domains in Kv7.2
Authors: Pant Shashank , Zhang Jiaren , Kim Eung Chang , Lam Kin , Chung Hee Jung , Tajkhorshid Emad 
Published: May 2021

AbstractPhosphatidylinositol-4,5-bisphosphate (PIP2) is a signaling lipid which regulates voltage-gated Kv7/KCNQ potassium channels. Altered PIP2 sensitivity of neuronal Kv7.2 channel is involved in KCNQ2 epileptic encephalopathy. However, the molecular action of PIP2 on Kv7.2 gating remains largely elusive. Here, we use molecular dynamics simulations and electrophysiology to characterize PIP2 binding sites in a human Kv7.2 channel. In the closed state, PIP2 localizes to the periphery of the voltage-sensing domain (VSD). In the open state, PIP2 binds to 4 distinct interfaces formed by the cytoplasmic ends of the VSD, the gate, intracellular helices A and B and their linkers. PIP2 binding induces bilayer-interacting conformation of helices A and B and the correlated motion of the VSD and the pore domain, whereas charge-neutralizing mutations block this coupling and reduce PIP2 sensitivity of Kv7.2 channels by disrupting PIP2 binding. These findings reveal the allosteric role of PIP2 in Kv7.2 channel activation.
Optimization of synthetic jet actuation by analytical modeling
Authors: Huber Max , Zienert Andreas , Weigel Perez , Schüller Martin , Berger Hans-Reinhard , Schuster Jörg , Otto Thomas 
Published: May 2021

Purpose
The purpose of this paper is to analyze and optimize synthetic jet actuators (SJAs) by means of a literature-known one-dimensional analytical model.

Design/methodology/approach
The model was fit to a wide range of experimental data from in-house built SJAs with different dimensions. A comprehensive parameter study was performed to identify coupling between parameters of the model and to find optimal dimensions of SJAs.

Findings
The coupling of two important parameters, the diaphragm resonance frequency and the cavity volume, can be described by a power law. Optimal orifice length and diameter can be calculated from cavity height in good agreement with literature. A transient oscillation correction is required to get correct simulation outcomes.

Originality/value
Based on these findings, SJA devices can be optimized for maximum jet velocity and, therefore, high performance.
Updates in service standards in hotels: how COVID-19 changed operations
Authors: Chan Janelle , Gao Yixing (Lisa) , McGinley Sean 
Published: May 2021

PurposeThe COVID-19 pandemic has tremendously affected the hospitality industry. With the experiences of severe acute respiratory syndrome in 2003 and commitments to ensure guests’ health and safety, many hotels in Asia have actively engaged in updating and implementing new service standards and measures. This study aims to investigate hotels’ service standard changes, processes of management decisions and preparations for the future.Design/methodology/approachUsing grounded theory methodology, this research interviews 24 hotel managers from mainland China and Hong Kong. It examines the differences among hotels with different operation types, classifications and locations, and analyzes the service standards in physical and social services cape.FindingsBuilding on the service marketing and crisis management literature, this research provides a synthesis that reflects how hotels have coped with the COVID-19 crisis. It depicts the service standard update process during the COVID-19.Research limitations/implicationsIn line with the literature in disaster management, hotels experienced the outbreak, response and recovery phases of the crisis management procedure. However, given the severity and scope of the COVID-19 pandemic, undertaking particular processes is necessary at every procedure such as following local guidelines and updating local standard operating procedures (LSOPs). This research also expands the literature on the process of adopting new technology in hotels during crisis management.Practical implicationsThe paper suggests that hotel managers should update and use well-thought-out standards on the bases of available scientific evidence. For example, hotels should use LSOPs according to the local situations. Hotels are also suggested to exert additional efforts and attention in service innovation, guest experience and enhancing hospitableness.Originality/valueTo the best of the authors’ knowledge, this paper is one of the first efforts to investigate the impact of COVID-19 on hotel operations. It offers empirical evidence from hotel operators who worked against the crisis during the pandemic and provides valuable theoretical contribution to the hospitality service literature as well as managerial implications for hotel operators globally.
Searching for a new perspective on institutional voids, networks and the internationalisation of SMEs in emerging economies: a systematic literature review
Authors: Dekel-Dachs Ofer , Najda-Janoszka Marta , Stokes Peter , Simba Amon , Tarba Shlomo 
Published: May 2021

PurposeThis study, a systematic review, focuses on the internationalisation of small and medium-sized enterprises (SMEs) originating in developing countries. It critically analyses, evaluates and synthesises studies featuring formal and informal institutions, embedded in social and business networks, as a marketing solution for institutional voids. The review shows that current international marketing studies downplay the role of informal institutions in the internationalisation of SMEs. Thus, the authors set a new research agenda for advancing the institutional theory to account for the impact of informal institutions and networks on firm internationalisation.Design/methodology/approachThis review followed five structured stages, including framing the research questions, identifying relevant studies, assessing their quality, summarising the evidence and interpreting the findings. Based on the systematic approach, 434 papers (374 from Web of Science, 60 from Scopus) were generated. Following that, the authors applied the qualitative inclusion/exclusion criteria, which yielded 63 papers. Their analysis involved three authors, with the fourth author focusing on ensuring quality in the analysis.FindingsThe study findings invite a different line of theorising market structures and processes focusing on the role of networks as an alternative to formal institutional systems. The outcome of our review suggests that there is scope for developing the institutional theory that account for the role of informal institutions and networks.Originality/valueBased on the analysis, we call for new theorisation, in the international marketing literature, which accounts for informal networking amongst internationalising SMEs in the light of institutional voids. Thus, the authors promote novel participatory, bottom to top understanding of relationship between institutions and enterprises.