Design of Polyurethane Fibers: Relation between the Spinning Technique and the Resulting Fiber Topology

International audienc

Learning and innovation of Chinese Firms along the paths of “Bring In” to “Go Global”

Over the past several decades, the “Bring In” and “Go Global” policies implemented in China have encouraged an unprecedented level of investment in and out of the country, creating unique opportunities for Chinese firms to learn and innovate along the paths of inward and outward internationalization. The international business (IB) literature has yet to satisfactorily explain what has been learnt by the Chinese firms and whether and how their learning and innovation have taken place over time. This special issue examines the specific content, nature, mechanisms, processes, and internal and external conditions and contexts of learning and innovation of Chinese firms during the course of inward and outward internationalization. We provide an overview of the “Bring In” and “Go Global” policies, assess the current state of the field, and explicate how the research articles in the special issue contribute to the understanding of learning and innovation of Chinese firms along the paths of inward and outward internationalization

International genome-wide meta-analysis identifies new primary biliary cirrhosis risk loci and targetable pathogenic pathways.

Primary biliary cirrhosis (PBC) is a classical autoimmune liver disease for which effective immunomodulatory therapy is lacking. Here we perform meta-analyses of discovery data sets from genome-wide association studies of European subjects (n=2,764 cases and 10,475 controls) followed by validation genotyping in an independent cohort (n=3,716 cases and 4,261 controls). We discover and validate six previously unknown risk loci for PBC (Pcombined<5 × 10(-8)) and used pathway analysis to identify JAK-STAT/IL12/IL27 signalling and cytokine-cytokine pathways, for which relevant therapies exist

A922 Sequential measurement of 1 hour creatinine clearance (1-CRCL) in critically ill patients at risk of acute kidney injury (AKI)

Meeting abstrac

COVID-19 symptoms at hospital admission vary with age and sex: results from the ISARIC prospective multinational observational study

Background: The ISARIC prospective multinational observational study is the largest cohort of hospitalized patients with COVID-19. We present relationships of age, sex, and nationality to presenting symptoms. Methods: International, prospective observational study of 60 109 hospitalized symptomatic patients with laboratory-confirmed COVID-19 recruited from 43 countries between 30 January and 3 August 2020. Logistic regression was performed to evaluate relationships of age and sex to published COVID-19 case definitions and the most commonly reported symptoms. Results: ‘Typical’ symptoms of fever (69%), cough (68%) and shortness of breath (66%) were the most commonly reported. 92% of patients experienced at least one of these. Prevalence of typical symptoms was greatest in 30- to 60-year-olds (respectively 80, 79, 69%; at least one 95%). They were reported less frequently in children (≤ 18 years: 69, 48, 23; 85%), older adults (≥ 70 years: 61, 62, 65; 90%), and women (66, 66, 64; 90%; vs. men 71, 70, 67; 93%, each P &lt; 0.001). The most common atypical presentations under 60 years of age were nausea and vomiting and abdominal pain, and over 60 years was confusion. Regression models showed significant differences in symptoms with sex, age and country. Interpretation: This international collaboration has allowed us to report reliable symptom data from the largest cohort of patients admitted to hospital with COVID-19. Adults over 60 and children admitted to hospital with COVID-19 are less likely to present with typical symptoms. Nausea and vomiting are common atypical presentations under 30 years. Confusion is a frequent atypical presentation of COVID-19 in adults over 60 years. Women are less likely to experience typical symptoms than men

Electrospun PMMA polymer blend nanofibrous membrane: electrospinability, surface morphology and mechanical response

The present work focuses on the electrospinning ability, the evaluation of resulting surface morphology and mechanical response of PMMA polymer blend nanofibrous membranes. For this purpose, electrospinning ability of PMMA polymer blend is firstly investigated by exploring various set of electrospinning parameters. From the evaluation of surface morphology of the resulting electrospun membranes, the optimum parameters are identified. Using these optimum parameters, tensile specimens are subsequently produced. Three deformation modes are considered: monotonic tensile test, cyclic test with increasing maximum strain and cyclic-relaxation test. Morphological analysis shows that the optimized tensile specimens are initially isotropic on the plane. The mechanical test results highlight the strong inelastic responses of the materials, which include inelastic strain and time-dependent behavior characterized by stress relaxation. Finally, in situ tensile test outcomes suggest that strain-induced fiber re-orientation took place

Poisson's ratio and volume change accompanying deformation of randomly oriented electrospun nanofibrous membranes

The present work focuses on the determination of volume change accompanying deformation and Poisson's ratio for electrospun nanofibrous membranes. For this purpose, polyurethane (PU) is considered for the fabrication of electrospun nanofibrous membranes. Three different sample thicknesses are fabricated. Following this, surface morphology analysis and fibre orientation analysis are conducted to investigate the variation of properties between electrospun PU membranes of different thicknesses. Subsequently, PU specimens are subjected to uniaxial extension test where the changes in sample width and thickness are recorded as a function of applied strain. Volume changes are computed while further analysis on the relationship between transverse strains and axial strain provided the values of Poisson's ratio. For all three electrospun PU samples investigated, significant volume changes are observed while the in-plane Poisson's ratio is found to be around 0.55. However, the out-of-plane Poisson's ratio of electrospun PU membranes are not classical and remains undetermined. © 2019, © 2019 Institute of Materials, Minerals and Mining Published by Taylor & Francis on behalf of the Institute

Design of Polyurethane Fibers: Relation between the Spinning Technique and the Resulting Fiber Topology

International audienc

Design of polyurethane fibers: Relation between the spinning technique and the resulting fiber topology

Properties or characteristics of fibers are affected by their topology. In fact, these topologies are found to have significant impacts in the functionalities of many applications. Hence, in this study, the relations between the spinning techniques and the topology of the resulting fibers are studied with the aim to provide a guideline for future reference where fibers with certain topology can be fabricated to suit specific applications. For this purpose, polyurethane is chosen to be the raw material to fabricate the fibers due to its versatility to be applied in various fields. The surface morphology, structures, and alignments of the fibers are studied. It is found that the polymer solution properties largely influence the mechanisms in the spinning process and can significantly affect the topology of the fibers. For instance, viscous solutions enable the spinning of coiled and smooth fibers, whereas conductive solutions encourage the splaying of the solution jet which results in the spinning of straight fibers. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47706. © 2019 Wiley Periodicals, Inc