Field studies in large numbers of subjects unselected for risk factors are needed to assess the true prevalence and health burden of hepatitis C virus (HCV) infection. We assessed the prevalence, virological characteristics, risk factors and evidence of liver disease in a population of healthy subjects from an urban area of Sardinia. Hepatitis B virus (HBV) markers were also studied. The prevalence of antibodies to HCV (anti-HCV) (recombinant immunoblot assay [RIBA]-confirmed positive results) was 3.19% in 3324 workers and 7.11% in 225 elderly subjects, with a cumulative anti-HCV prevalence of 2.70% (95% CI 2.17-3.24). Males were more frequently positive than females (P < 0.01). The age-specific prevalence of HCV infection increased progressively in females. It showed two peaks in males: one in the fourth decade, the other in the seventh decade. HCV RNA was detected in 63.16% of the RIBA-positive sera, in 10% of the RIBA indeterminates and in none of the RIBA-negative specimens. Only 1.75% of anti-HCV-positive subjects had elevated transaminases. The frequency of HCV genotype 1b was 32.79%; of 1a, 21.31%; of 3a, 19.67%; of 4, 13.11%; and of 2a, 13.11%. HBV markers were found in 28.03% of workers. On multivariate analysis, male gender and tattooing were significantly associated with HCV and HBV infections: transfusion and travel with HCV, and age over 40 with HBV. The age prevalence rates of HCV infection in the Cagliari area reflect different risk factors that have been operative at different times. In this urban area, the large majority of HCV infections run a subclinical course.
The CMS Data Acquisition System is designed to build and filter events originating from 476 detector data sources at a maximum trigger rate of 100 KHz. Different architectures and switch technologies have been evaluated to accomplish this purpose. Events will be built in two stages: the first stage will be a set of event builders called FED Builders. These will be based on Myrinet technology and will pre-assemble groups of about 8 data sources. The second stage will be a set of event builders called Readout Builders. These will perform the building of full events. A single Readout Builder will build events from 72 sources of 16 KB fragments at a rate of 12.5 KHz. In this paper we present the design of a Readout Builder based on TCP/IP over Gigabit Ethernet and the optimization that was required to achieve the design throughput. This optimization includes architecture of the Readout Builder, the setup of TCP/IP, and hardware selection.
Presented by Matteo Sani at IEEE NPSS Real Time 2007,
Question: Vegetation in the alpine and treeline ecotone faces changes in both climate and land use. Shrub encroachment is considered an effect of these changes, but it′s still unclear how this effect is mediated by environmental heterogeneity. Our goal is to determine which environmental factors shape the fine-scale spatial distribution and temporal trends of alpine dwarf shrub. Location: Three sites in the Central Apennine, Italy. Methods: We used a comprehensive set of environmental factors across a broad temporal span to model, at a fine-scale, both (1) the current spatial distribution and (2) the change in shrub cover over the past 60 years. Results: Our results show that dwarf shrubs have generally increased in our study sites over the past 60 years, yet their distribution is strongly shaped by the joint influence of the fine-scale topography, productivity, land use and micro-climate. In particular, shrubs have been locally favored in areas with harsher alpine environmental constraints and stronger resource limitation. Instead, contrary to expectations, at this fine scale, warmer temperatures and the decline in grazing have not favored shrub encroachment. Conclusion: Dwarf shrubs appear as a stress-tolerant, pioneer vegetation that is currently distributed mainly over areas that are otherwise sparsely vegetated. It appears that shrubs exhibit poor competitive ability to invade grasslands and, though they have increased overall, they remain restricted to the least productive areas. Fine-scale environmental heterogeneity may strongly influence future responses of dwarf shrubs in changing alpine ecosystems.
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