1,972 research outputs found
Suppression of von K\'arm\'an vortex streets past porous rectangular cylinders
Although the stability properties of the wake past impervious bluff bodies
have been widely examined in the literature, similar analyses regarding the
flow around and through porous ones are still lacking. In this work, the effect
of the porosity and permeability on the wake patterns of porous rectangular
cylinders is numerically investigated at low to moderate Reynolds numbers in
the framework of direct numerical simulation combined with local and global
stability analyses. A modified Darcy-Brinkman formulation is employed here so
as to describe the flow behavior inside the porous media, where also the
convective terms are retained to correctly account for the inertial effects at
high values of permeability. Different aspect ratios of the cylinder are
considered, varying the thickness-to-height ratios, t/d, from 0.01 (flat plate)
to 1.0 (square cylinder). The results show that the permeability of the bodies
has a strong effect in modifying the characteristics of the wakes and of the
associated flow instabilities, while the porosity weakly affects the resulting
flow patterns. In particular, the fluid flows through the porous bodies and,
thus, as the permeability is progressively increased, the recirculation
regions, initially attached to the rear part of the bodies, at first detach
from the body and, eventually, disappear even in the near wakes. Global
stability analyses lead to the identification of critical values of the
permeability above which any linear instability is prevented. Moreover, a
different scaling of the non-dimensional permeability allows to identify a
general threshold for all the configurations here studied that ensures the
suppression of vortex shedding, at least in the considered parameter space.Comment: 31 pages and 17 figure
La situaciĂłn del sector vivienda en la RepĂşblica Argentina
Abstract not available.Resumen no disponible
Parameter estimation of binary black holes in the endpoint of the up-down instability
Black-hole binary spin precession admits equilibrium solutions corresponding
to systems with (anti-) aligned spins. Among these, binaries in the up-down
configuration, where the spin of the heavier (lighter) black hole is co-
(counter-) aligned with the orbital angular momentum, might be unstable to
small perturbations of the spin directions. The occurrence of the up-down
instability leads to gravitational-wave sources that formed with aligned spins
but are detected with precessing spins. We present a Bayesian procedure based
on the Savage-Dickey density ratio to test the up-down origin of
gravitational-wave events. This is applied to both simulated signals, which
indicate that achieving strong evidence is within the reach of current
experiments, and the LIGO/Virgo events released to date, which indicate that
current data are not informative enough
NAB2 is a novel immune stimulator of MDA-5 that promotes a strong type I interferon response
Novel adjuvants are needed to increase the efficacy of vaccine formulations and immune therapies for cancer and chronic infections. In particular, adjuvants that promote a strong type I IFN response are required, since this cytokine is crucial for the development of efficient anti-tumoral and anti-viral immunity. Nucleic acid band 2 (NAB2) is a double- stranded RNA molecule isolated from yeast and identified as an agonist of the pattern- recognition receptors TLR3 and MDA-5. We compared the ability of NAB2 to activate innate immunity with that of poly(I:C), a well-characterized TLR3 and MDA-5 agonist known for the induction of type I IFN. NAB2 promoted stronger IFN-α production and induced a higher activation state of both murine and human innate immune cells compared to poly(I:C). This correlated with a stronger activation of the signalling pathway downstream of MDA-5, and IFN-α induction was dependent on MDA-5. Upon injection, NAB2 induced higher levels of serum IFN-α in mice than poly(I:C). These results suggest that NAB2 has the potential to become an efficient adjuvant for the induction of type-I IFN responses in therapeutic immunization against cancer or infections
Glycemic Control in Type 1 Diabetes Mellitus During COVID-19 Quarantine and the Role of In-Home Physical Activity.
Background: To limit the spread of coronavirus disease 2019 (COVID-19), governments have ordered a series of restrictions that may affect glycemic control in individuals with type 1 diabetes mellitus (T1DM), since physical activity (PA) was not allowed outside home. Methods: We retrospectively evaluated glycemic control of individuals with T1DM using hybrid closed loop (HCL) system in the period before the SARS-CoV-2 outbreak in Italy (February 10-23, 2020-Time 1), when movements were only reduced (February 24-March 8, 2020-Time 2) and during complete lockdown (March 9-22, 2020-Time 3). Information about regular PA (at least 3 h per week) prior and during the quarantine was collected. Results: The study included 13 individuals with a median age of 14.2 years and a good glycemic control at baseline (glucose management indicator of 7%, time in range [TIR] of 68%, time below range [TBR] of 2%). All individuals continued to show good glycemic control throughout the study period. There was an increase in TIR during the study period (+3%) and TIR was significantly higher during Time 3 (72%) than during Time 2 (66%). TBR was significantly lower during Time 3 (1%) both compared with Time 1 and Time 2 (2%). A meaningful variance in TIR at Time 3 between individuals who performed or not PA during quarantine and a significant increase in TIR between Time 2 and Time 3 in individuals both doing PA at baseline and during quarantine was found. At logistic regression, only the presence of PA during quarantine significantly predicted a TIR >70%. Conclusions: Glycemic control of T1DM in adolescents using HCL system did not worsen during the restrictions due to COVID-19 pandemics and further improved in those who continued PA during the quarantine. Maintaining regular PA in a safe home environment is an essential strategy for young individuals with T1DM during the COVID-19 crisis
A rare urinary JC virus reactivation after long-term therapy with rituximab
Abstract The possible role of JC virus in determining urinary tract involvement has only recently been recognized. The case of a man with laboratory-confirmed JC virus replication in the urine after a maintenance schedule of rituximab administered for a lymphoproliferative disorder is reported herein. The patient developed severe renal and urinary tract impairment, characterized by the onset of nephropathy, bilateral ureteral strictures, and a serious reduction in vesical compliance, ultimately requiring an ileal neobladder configuration. The renal and urinary tract involvement was finally attributed to JC virus reactivation. This observation suggests that renal and urinary tract diseases related to JC virus might be associated with long-term rituximab treatment
Il ruolo degli indicatori ESG nel “Modello di Business Sostenibile”: un’analisi sistematica della letteratura
The definition of firm has always been outlined by the neoclassical theory with the idea that strategy is the core of a business model (Rumelt, 1997). External factors, such as social and environmental aspects of the activity, play the role of moderators in the relationship between strategy processes and organizational performance (Goll, Rasheed, 1997). Starting from this point of view, companies have a crucial role in shaping the future of society: is it always true that companies must ensure sustainability through sustainable business models? The most representative theoretical reference models agree that the implementation of Environmental, Social and Governance (ESG) indicators in the modern company represent the way to achieve a valid sustainable business model (Kocmanová, Dočekalová, 2012). This paper seeks to find, from the existing literature on ESG indicators, an answer to the initial general question and to create a literature framework about the sustainable business models. The first part of the work will outline, through a systematic analysis of the literature and its primary and secondary sources, the most important research contributions about ESG while the second part will analyse the collected data. Specific key words will be subsequently isolated, and their role and frequency will be studied through a word cloud analysis and the realization of a dendrogram.
The main results will point out a strong link between performance and ESG practices and will show the impact of such indicators in terms of stakeholders and investors relationship. Finally, some research ideas, linked with the identified critical issues of the literature, will be suggested for a future approach to the topic
Train-the-trainer booklet bioeconomy and the UrBioFuture experience
Objective of this training is to bring your attention, as educators, to the importance of the bioindustry and the opportunities that it creates for the young people. In this booklet we will share with you tailored made educational and multimedia materials so you can use it in your classes and become the Ambassadors of UrBioFuture Experience
EpiGEN: an epistasis simulation pipeline
Abstract
Summary
Simulated data are crucial for evaluating epistasis detection tools in genome-wide association studies. Existing simulators are limited, as they do not account for linkage disequilibrium (LD), support limited interaction models of single nucleotide polymorphisms (SNPs) and only dichotomous phenotypes or depend on proprietary software. In contrast, EpiGEN supports SNP interactions of arbitrary order, produces realistic LD patterns and generates both categorical and quantitative phenotypes.
Availability and implementation
EpiGEN is implemented in Python 3 and is freely available at https://github.com/baumbachlab/epigen.
Supplementary information
Supplementary data are available at Bioinformatics online
COVID-19 and Type 1 Diabetes: Concerns and Challenges
Due to the current COVID-19 pandemic, worldwide population's lifestyle has changed dramatically, causing psychosocialconsequences. Patients presenting a preexisting chronic condition, as Type 1 Diabetes (T1D), are the ones suffering the most from this situation. Moreover, people affected by diabetes are the ones with the worst prognosis, if infected by SARS-CoV-2. We analyzed why patients with T1D were poorly represented between the subjects hospitalized for COVID-19 and why the cases of diabetic ketoacidosis (DKA) were fewerand more severe compared with the past years. Furthermore, literature has showed howpatients of all ages with T1D did not experience a deterioration in their glucose control throughout the lockdown. Among other causes, this is also due tothe surging use of telemedicine. Finally, we tried to understand how the coronavirus tropism for endocrine tissues could influence the future epidemiology of T1D, focusing on the effects they have on pancreatic beta-cells
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