Search results for " Variation"

Recent Change—Terrestrial Cryosphere

2015

This chapter compiles and assesses information on recent and current change within the terrestrial cryosphere of the Baltic Sea drainage basin. Findings are based on long-term observations. Snow cover extent (SCE), duration and amount have shown a widespread decrease although there is large interannual and regional variation. Few data are available on changes in snow structural properties. There is no evidence for a recent change in the frequency or severity of snow-related extreme events. There has been a decrease in glacier coverage in Sweden and glacier ice thickness in inland Scandinavia. The European permafrost is warming, and there has been a northward retreat of the southern boundary…

Microbial succession of nitrate-reducing bacteria in the rhizosphere of Poa alpina across a glacier foreland in the Central Alps

2006

International audience; Changes in community structure and activity of the dissimilatory nitrate-reducing community were investigated across a glacier foreland in the Central Alps to gain insight into the successional pattern of this functional group and the driving environmental factors. Bulk soil and rhizosphere soil of Poa alpina was sampled in five replicates in August during the flowering stage and in September after the first snowfalls along a gradient from 25 to 129 years after deglaciation and at a reference site outside the glacier foreland (> 2000 years deglaciated). In a laboratory-based assay, nitrate reductase activity was determined colorimetrically after 24 h of anaerobic inc…

Norma y variación lingüística: paralelismos y divergencias entre el español y el catalán

2013

Este artículo analiza la presencia de la variación lingüística de carácter dialectal en la norma académica o modelo de lengua estándar del español y del catalán. Esta variación se manifiesta a través de la aceptación de alternativas normativas, también conocida como polimorfismo. El estudio se centra en la lengua escrita, concretamente en el nivel ortográfico, en el morfológico y en el sintáctico, y analiza los contenidos de las principales obras académicas de estas dos lenguas. El hecho de tratarse de lenguas con una situación sociolingüística diferente tiene consecuencias en la manera de concebir el posible polimorfismo y también en la forma de aplicarlo, ya que entra en conflicto la defe…

Balance equations-based properties of the Rabi Hamiltonian

2014

A stationary physical system satisfies peculiar balance conditions involving mean values of appropriate observables. In this paper we show how to deduce such quantitative links, named balance equations, demonstrating as well their usefulness in bringing to light physical properties of the system without solving the Schrodinger equation. The knowledge of such properties in the case of Rabi Hamiltonian is exploit to provide arguments to make easier the variational engineering of the ground state of this model.

Genetic Determinants in a Critical Domain of NS5A Correlate with Hepatocellular Carcinoma in Cirrhotic Patients Infected with HCV Genotype 1b

2021

HCV is an important cause of hepatocellular carcinoma (HCC). HCV NS5A domain-1 interacts with cellular proteins inducing pro-oncogenic pathways. Thus, we explore genetic variations in NS5A domain-1 and their association with HCC, by analyzing 188 NS5A sequences from HCV genotype-1b infected DAA-naïve cirrhotic patients: 34 with HCC and 154 without HCC. Specific NS5A mutations significantly correlate with HCC: S3T (8.8% vs. 1.3%, p = 0.01), T122M (8.8% vs. 0.0%, p &lt

A Novel Approach to Identify Candidate Prognostic Factors for Hepatitis C Treatment Response Integrating Clinical and Viral Genetic Data

2015

The combined therapy of pegylated interferon (IFN) plus ribavirin (RBV) has been for a long time the standard treatment for patients infected with hepatitis C virus (HCV). In the case of genotype 1, only 38%–48% of patients have a positive response to the combined treatment. In previous studies, viral genetic information has been occasionally included as a predictor. Here, we consider viral genetic variation in addition to 11 clinical and 19 viral populations and evolutionary parameters to identify candidate baseline prognostic factors that could be involved in the treatment outcome. We obtained potential prognostic models for HCV subtypes la and lb in combination as well as separately. We …

A systematic review of the literature on the human genetic variations in response to vaccination

2012

BACKGROUND: Vaccinomics is a term that refers to the investigation of heterogeneity of host genetic markers at the individual or population level that may result in variations of humoral, cell-mediated, and/or innate immune responses to vaccines. Studying genetic heterogeneity of human response to vaccines is supposed to both afford a better understanding of the way vaccine works, and help in developing future vaccines that are protective. With this premise in mind, we performed a systematic review of the literature on the studies concerning the association between human genetic variations in response to vaccination. METHODS: A detailed literature search on the case-control and cohort studi…

Numerical simulation of river-bed variations: Sensitivity analyses with respect of the initial hydraulic roughness

2020

Two elements affect the efficacy of the numerical models of mobile-bed evolution: the prediction of the hydraulic roughness, related with both sediment distribution on the bed and flow depth, and the prediction of the hydraulic sorting, when the distribution of sediments on the bed is not uniform. In this work the bed profile variation is simulated, by using a numerical model proposed in previous works, in function of the variation of the friction factor, that reflects the coarsening of median sediment diameter, due to armouring process, and the variation of flow conditions. The variation of grains-size distribution of the bed material is predicted by using a probabilistic approach and the …

Evolutionary ecology of complex life cycle parasites : from genotypes to species assemblages

2012

EPR DOSIMETRY IN A MIXED NEUTRON AND GAMMA RADIATION FIELD

2004

Suitability of Electron Paramagnetic Resonance (EPR) spectroscopy for criticality dosimetry was evaluated for tooth enamel, mannose and alanine pellets during the 'international intercomparison of criticality dosimetry techniques' at the SILENE reactor held in Valduc in June 2002, France. These three materials were irradiated in neutron and gamma-ray fields of various relative intensities and spectral distributions in order to evaluate their neutron sensitivity. The neutron response was found to be around 10% for tooth enamel, 45% for mannose and between 40 and 90% for alanine pellets according their type. According to the IAEA recommendations on the early estimate of criticality accident a…