19 research outputs found

    Fluctuating Elastic Rings: Statics and Dynamics

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    We study the effects of thermal fluctuations on elastic rings. Analytical expressions are derived for correlation functions of Euler angles, mean square distance between points on the ring contour, radius of gyration, and probability distribution of writhe fluctuations. Since fluctuation amplitudes diverge in the limit of vanishing twist rigidity, twist elasticity is essential for the description of fluctuating rings. We find a crossover from a small scale regime in which the filament behaves as a straight rod, to a large scale regime in which spontaneous curvature is important and twist rigidity affects the spatial configurations of the ring. The fluctuation-dissipation relation between correlation functions of Euler angles and response functions, is used to study the deformation of the ring by external forces. The effects of inertia and dissipation on the relaxation of temporal correlations of writhe fluctuations, are analyzed using Langevin dynamics.Comment: 43 pages, 9 Figure

    Geographical and temporal distribution of SARS-CoV-2 clades in the WHO European Region, January to June 2020

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    We show the distribution of SARS-CoV-2 genetic clades over time and between countries and outline potential genomic surveillance objectives. We applied three available genomic nomenclature systems for SARS-CoV-2 to all sequence data from the WHO European Region available during the COVID-19 pandemic until 10 July 2020. We highlight the importance of real-time sequencing and data dissemination in a pandemic situation. We provide a comparison of the nomenclatures and lay a foundation for future European genomic surveillance of SARS-CoV-2.Peer reviewe

    UBVRI Light curves of 44 Type Ia supernovae

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    We present UBVRI photometry of 44 Type la supernovae (SNe la) observed from 1997 to 2001 as part of a continuing monitoring campaign at the Fred Lawrence Whipple Observatory of the Harvard-Smithsonian Center for Astrophysics. The data set comprises 2190 observations and is the largest homogeneously observed and reduced sample of SNe la to date, nearly doubling the number of well-observed, nearby SNe la with published multicolor CCD light curves. The large sample of [U-band photometry is a unique addition, with important connections to SNe la observed at high redshift. The decline rate of SN la U-band light curves correlates well with the decline rate in other bands, as does the U - B color at maximum light. However, the U-band peak magnitudes show an increased dispersion relative to other bands even after accounting for extinction and decline rate, amounting to an additional ∼40% intrinsic scatter compared to the B band

    Steady-State Configuration of an Underwater Suspended Bipod Cable System

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    The usage, quality and relevance of information and communications technologies in patients with chronic urticaria: A UCARE study

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    Background: Chronic urticaria (CU) is characterized by itchy recurrent wheals, angioedema, or both for 6 weeks or longer. CU can greatly impact patients' physical and emotional quality of life. Patients with chronic conditions are increasingly seeking information from information and communications technologies (ICTs) to manage their health. The objective of this study was to assess the frequency of usage and preference of ICTs from the perspective of patients with CU. Methods: In this cross-sectional study, 1800 patients were recruited from primary healthcare centers, university hospitals or specialized clinics that form part of the UCARE (Urticaria Centers of Reference and Excellence) network throughout 16 countries. Patients were >12 years old and had physician-diagnosed chronic spontaneous urticaria (CSU) or chronic inducible urticaria (CIndU). Patients completed a 23-item questionnaire containing questions about ICT usage, including the type, frequency, preference, and quality, answers to which were recorded in a standardized database at each center. For analysis, ICTs were categorized into 3 groups as follows: one-to-one: SMS, WhatsApp, Skype, and email; one-to-many: YouTube, web browsers, and blogs or forums; many-to-many: Instagram, Twitter, Facebook, and LinkedIn. Results: Overall, 99.6% of CU patients had access to ICT platforms and 96.7% had internet access. Daily, 85.4% patients used one-to-one ICT platforms most often, followed by one-to-many ICTs (75.5%) and many-to-many ICTs (59.2%). The daily ICT usage was highest for web browsers (72.7%) and WhatsApp (70.0%). The general usage of ICT platforms increased in patients with higher levels of education. One-to-many was the preferred ICT category for obtaining general health information (78.3%) and for CU-related information (75.4%). A web browser (77.6%) was by far the most commonly used ICT to obtain general health information, followed by YouTube (25.8%) and Facebook (16.3%). Similarly, for CU-specific information, 3 out of 4 patients (74.6%) used a web browser, 20.9% used YouTube, and 13.6% used Facebook. One in 5 (21.6%) patients did not use any form of ICT for obtaining information on CU. The quality of the information obtained from one-to-many ICTs was rated much more often as very interesting and of good quality for general health information (53.5%) and CU-related information (51.5%) as compared to the other categories. Conclusions: Usage of ICTs for health and CU-specific information is extremely high in all countries analyzed, with web browsers being the preferred ICT platform. © 202

    The usage, quality and relevance of information and communications technologies in patients with chronic urticaria: a UCARE study

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    Background: Chronic urticaria (CU) is characterized by itchy recurrent wheals, angioedema, or both for 6 weeks or longer. CU can greatly impact patients' physical and emotional quality of life. Patients with chronic conditions are increasingly seeking information from information and communications technologies (ICTs) to manage their health. The objective of this study was to assess the frequency of usage and preference of ICTs from the perspective of patients with CU. Methods: In this cross-sectional study, 1800 patients were recruited from primary healthcare centers, university hospitals or specialized clinics that form part of the UCARE (Urticaria Centers of Reference and Excellence) network throughout 16 countries. Patients were >12 years old and had physician-diagnosed chronic spontaneous urticaria (CSU) or chronic inducible urticaria (CIndU). Patients completed a 23-item questionnaire containing questions about ICT usage, including the type, frequency, preference, and quality, answers to which were recorded in a standardized database at each center. For analysis, ICTs were categorized into 3 groups as follows: one-to-one: SMS, WhatsApp, Skype, and email; one-to-many: YouTube, web browsers, and blogs or forums; many-to-many: Instagram, Twitter, Facebook, and LinkedIn. Results: Overall, 99.6% of CU patients had access to ICT platforms and 96.7% had internet access. Daily, 85.4% patients used one-to-one ICT platforms most often, followed by one-to-many ICTs (75.5%) and many-to-many ICTs (59.2%). The daily ICT usage was highest for web browsers (72.7%) and WhatsApp (70.0%). The general usage of ICT platforms increased in patients with higher levels of education. One-to-many was the preferred ICT category for obtaining general health information (78.3%) and for CU-related information (75.4%). A web browser (77.6%) was by far the most commonly used ICT to obtain general health information, followed by YouTube (25.8%) and Facebook (16.3%). Similarly, for CU-specific information, 3 out of 4 patients (74.6%) used a web browser, 20.9% used YouTube, and 13.6% used Facebook. One in 5 (21.6%) patients did not use any form of ICT for obtaining information on CU. The quality of the information obtained from one-to-many ICTs was rated much more often as very interesting and of good quality for general health information (53.5%) and CU-related information (51.5%) as compared to the other categories. Conclusions: Usage of ICTs for health and CU-specific information is extremely high in all countries analyzed, with web browsers being the preferred ICT platform
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