Search results for "SMIS"

Quantifying transmission fitness costs of multi-drug resistant tuberculosis.

2021

As multi-drug resistant tuberculosis (MDR-TB) continues to spread, investigating the transmission potential of different drug-resistant strains becomes an ever more pressing topic in public health. While phylogenetic and transmission tree inferences provide valuable insight into possible transmission chains, phylodynamic inference combines evolutionary and epidemiological analyses to estimate the parameters of the underlying epidemiological processes, allowing us to describe the overall dynamics of disease spread in the population. In this study, we introduce an approach to Mycobacterium tuberculosis (M. tuberculosis) phylodynamic analysis employing an existing computationally efficient mod…

Saprophytism of a fish pathogen as a transmission strategy

2009

Fish farming creates conditions where disease transmission is enhanced and antibiotic treatments are commonly used to cure bacterial diseases to prevent severe losses due to infections. Ability to persist in such an environment has been suggested to lead to the evolution of high virulence. Columnaris disease caused by Flavobacterium columnare is a growing problem in freshwater fish farming. Transmission of the disease is poorly known, and survival of F. columnare in the rearing environment has not been studied. This paper addresses both transmission of columnaris disease and survival strategy of F. columnare. Saprophytic activity of F. columnare was studied by infecting rainbow trout finger…

Co-circulation of SARS-CoV-2 Alpha and Gamma variants in Italy, February and March 2021

2022

Background Several SARS-CoV-2 variants of concern (VOC) have emerged through 2020 and 2021. There is need for tools to estimate the relative transmissibility of emerging variants of SARS-CoV-2 with respect to circulating strains. Aim We aimed to assess the prevalence of co-circulating VOC in Italy and estimate their relative transmissibility. Methods We conducted two genomic surveillance surveys on 18 February and 18 March 2021 across the whole Italian territory covering 3,243 clinical samples and developed a mathematical model that describes the dynamics of co-circulating strains. Results The Alpha variant was already dominant on 18 February in a majority of regions/autonomous provinces (…

Structure and composition heterogeneity of a FeAl alloy prepared by one-step synthesis and consolidation processing and their influence on grain size…

2006

Abstract This paper aims to characterize a bulk dense FeAl (47 at.%) alloy synthesized and consolidated by one-step current-activated pressure-assisted processing of nanocrystalline elemental powders. The end-product was analyzed using a combination of scanning (SEM) and transmission electron microscopies (TEM), electron back-scattering diffraction (EBSD) as well as electron probe microanalysis (EPMA). Special attention was paid to verify the grain size (32–89 nm) previously determined by X-ray diffraction peak profile analysis. It has been found that this material displays equiaxed grains (0.8–4 μm in size) and contains limited structural defects like subgrains and dislocations. The EPMA r…

Volatility transmission patterns and terrorist attacks

2009

The objective of this study is to analyze volatility transmission between the US and Eurozone stock markets considering the effects of the September 11, March 11 and July 7 financial crises. In order to do this, we use a multivariate GARCH model and take into account the asymmetric volatility phenomenon, the non-synchronous trading problem and the crises themselves. Moreover, a graphical analysis of the Asymmetric Volatility Impulse-Response Functions (AVIRF) is introduced, which takes into consideration the crisis effect. Results suggest that there is bidirectional and asymmetric volatility transmission and show the different impact that terrorist attacks had on both markets. El objetivo d…

El artículo 18 del estatuto de los trabajadores italiano a la luz de las últimas reformas laborales

2015

En las siguientes líneas se realizará un somero repaso sobre las principales las modificaciones de la disciplina italiana de los despidos individuales recogida en el artículo 18 del Estatuto de los Trabajadores italiano, introducidas por las últimas reformas laborales. En ellas se constará el impacto de dichas reformas en el cuadro legislativo de referencia, viéndose reducida la posibilidad de readmisión del trabajador en el caso de despido individual improcedente. Además se harán unos apuntes críticos sobre el concepto de flexsecurity, de cual se destaca una gran inflación en el presente contexto de crisis económica. This paper examines the amendments made to the Italian regulation of indi…

Orthogonal Multicarrier Transmission with Modal Channel Estimation

2009

A novel multi-carrier orthogonal transmission scheme is presented. While being simpler to implement, it has a spectral efficiency and design parameters similar to those of Orthogonal Frequency Division Multiplexing based on Offset Quadrature Amplitude Modulation (OFDM/OQAM). A parametric channel estimation technique is subsequently reported. The proposed technique is based on an algorithm obtained from classic Multiple Signal Classification (MUSIC) by relaxation of the hypothesis on the number of measurements with respect to the number of sensors. Numerical simulations show that our proposal outperforms previous works in this field.

2020

Vector-borne diseases such as malaria, dengue fever, West Nile virus, and so forth are some of the most prominent threats to human health. They are transmitted to the human population by infected insects or by direct transmission between humans. The epidemic process relies on suitable environmental and climatic conditions. Indeed, climatic factors affect the development of pathogens in vectors as well as the population dynamics of the vectors impacting significantly the incidence of disease in the human population. While the influence of the climatic conditions on Vector-borne diseases is well-documented, there is a strong need to design more realistic epidemiological models incorporating e…

Non-parametric probabilistic forecasting of academic performance in Spanish high school using an epidemiological modelling approach

2013

Academic underachievement is a concern of paramount importance in Europe, and particularly in Spain, where around of 30% of the students in the last two courses in high school do not achieve the minimum knowledge academic requirement. In order to analyse this problem, we propose a mathematical model via a system of ordinary differential equations to study the dynamics of the academic performance in Spain. Our approach is based on the idea that both, good and bad study habits, are a mixture of personal decisions and influence of classmates. Moreover, in order to consider the uncertainty in the estimation of model parameters, a bootstrapping approach is employed. This technique permits to for…

SY26-2ACETALDEHYDE ENDOCANNABINOIDS AND DOPAMINE: IS THIS –JUST- “A MENAGE A TROIS”?

2015

As ethanol, its first metabolite, acetaldehyde (ACD), enhances dopamine neurotransmission and exerts rewarding and motivational effects in animal models tailored for studying addictive-like behaviours. The endocannabinoid system fine-tuning dopamine cell activity, affects distinct drug-related behaviours and specific drug-induced effects. In light of this, it becomes urgent to investigate the implications of …