883 resultados para Project 2002-024-B : Team Collaboration in High Bandwidth Virtual Environments
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Neuronal proliferation, migration, and differentiation are regulated by the sequential expression of particular genes at specific stages of development. Such processes rely on differential gene expression modulated through second-messenger systems. Early postnatal mouse cerebellar granule cells migrate into the internal granular layer and acquire differentiated properties. The neurotransmitter glutamate has been shown to play an important role in this developmental process. We show here by immunohistochemistry that the RelA subunit of the transcription factor NF-kappa B is present in several areas of the mouse brain. Moreover, immunofluorescence microscopy and electrophoretic mobility-shift assay demonstrate that in cerebellar granule cell cultures derived from 3- to 7-day-old mice, glutamate specifically activates the transcription factor NF-kappa B, as shown by binding of nuclear extract proteins to a synthetic oligonucleotide reproducing the kappa B site of human immunodeficiency virus. The use of different antagonists of the glutamate recpetors indicates that the effect of glutamate occurs mainly via N-methyl-D-aspartate (NMDA)-receptor activation, possibly as a result of an increase in intracellular Ca2+. The synaptic specificity of the effect is strongly suggested by the observation that glutamate failed to activate NF-kappa B in astrocytes, while cytokines, such as interleukin 1 alpha and tumor necrosis factor alpha, did so. The effect of glutamate appears to be developmentally regulated. Indeed, NF-kappa B is found in an inducible form in the cytoplasm of neurons of 3- to 7-day-old mice but is constitutively activated in the nuclei of neurons derived from older pups (8-10 days postnatal). Overall, these observations suggest the existence of a new pathway of trans-synaptic regulation of gene expression.
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Intramuscular injection of plasmid DNA expression vectors encoding the three envelope proteins of the hepatitis B virus (HBV) induced humoral responses in C57BL/6 mice specific to several antigenic determinants of the viral envelope. The first antibodies appeared within 1-2 weeks after injection of DNA and included antibodies of the IgM isotype. Over the next few weeks, an IgM to IgG class switch occurred, indicating helper T-lymphocyte activity. Peak IgG titers were reached by 4-8 weeks after a single DNA injection and were maintained for at least 6 months without further DNA injections. The antibodies to the envelope proteins reacted with group- and subtype-specific antigenic determinants of the HBV surface antigen (HBsAg). Expression vectors encoding the major (S) and middle (preS2 plus S) envelope proteins induced antibodies specific to the S protein and preS2 domain, and preS2 antibodies were prominent at early time points. In general, the expression vectors induced humoral responses in mice that mimic those observed in humans during the course of natural HBV infection.
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Concussive injuries appear to be becoming a more common occurrence among athletes. While many studies have assessed the short-term and long-term effects of concussive injuries, fewer studies have specifically addressed the impact of multiple concussive injuries within a high school population. Through the use of the Immediate Post-Concussion Assessment and Cognitive Testing measure (ImPACT), this study investigated differences in a sample of 946 high school athletes with varying concussive histories (multiple concussions vs. single concussion vs. no concussion) at baseline and following sustaining a concussive injury. An additional analysis was conducted with athletes who obtained two concussions within the study to assess for trends in symptomology between their first and second injuries. For both baseline and study concussed athletes, athletes with multiple concussive injuries did not exhibit significantly elevated self-report symptoms nor decreased ImPACT composite scores compared to the other groups. Analysis of data from athletes who sustained more than one concussion within the study, revealed an increase in self-report symptoms and a decrease in ImPACT performance from time 1 to time 2. However, these changes were small in magnitude and were not consistently exhibited across the variables under investigation. Overall, this study did not find compelling evidence of increased symptomological patterns or decreased functioning for multiple concussed athletes as compared to peers.
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Triathlon is considered an endurance sport composed by the individual disciplines of swimming, cycling and running which are generally completed in this sequential order. It has been suggested that triathlon performance can be predicted by maximal oxygen uptake (VO2max). However, it has also been suggested that some variables such age, gender, fitness, training and ventilator muscles may affect VO2max. It is the aim of this research to measure and analyze the VO2max of 6 national elite triathletes and one national juvenile triathlete, with long experience, training in a high altitude city (1650m). We compare VO2max for female and male groups. We found differences at the VO2max values for these groups. Additionally, we also found high values of VO2max for these young elite triathletes despite their relative short age, but long sport age.
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Fuenterrabía (Hondarribia) is a town located on the Franco-Spanish border. Between the 16th and 19th centuries it was considered to be one of the most outstanding strongholds in the Basque Country due to its strategic position. The bastion system of fortification was extremely prevalent in this stronghold. It was one of the first Spanish towns to adopt the incipient Renaissance designs of the bastion. The military engineers subsequently carried out continuous fortification projects that enabled the structure to withstand the advances being made in artillery and siege tactics. After the construction of the citadel of Pamplona had begun in 1571, following the design of the prestigious military engineer, Jacobo Palear Fratín and being revised by Viceroy Vespasiano Gonzaga, the aforementioned engineer undertook an ambitious project commissioned by Felipe II to modernise the fortifications of Fuenterrabía. Neither the plans nor the report of this project have been conserved, but in the year 2000, César Fernández Antuña published the report written by Spannocchi on the state of the fortifications of Fuenterrabía when he arrived to the Spanish peninsula, discovered in the Archivo Histórico Provincial de Zaragoza. This document conducts an in-depth analysis of Spannocchi’s project and how it was related to Fratín’s previous project. It concludes that this project encountered problems in updating the new bastions at the end of the 16th century, and identifies the factors which prevented the stronghold from being extended as was the case in Pamplona after Fratín’s project.
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no.12(1926)
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East Lake, located at Cape Bounty (Melville Island, Canadian High Arctic), was mapped using a high-resolution swath bathymetric sonar and a 12 kHz sub-bottom profiler, allowing for the first time the imaging of widespread occurrence of mass movement deposits (MMDs) in a Canadian High Arctic Lake. Mass movements occurred mostly on steep slopes located away from deltaic sedimentation. The marine to lacustrine transition in the sediment favours the generation of mass movements where the underlying massive mud appears to act as a gliding surface for the overlying varved deposits. Based on acoustic stratigraphy, we have identified at least two distinct events that triggered failures in the lake during the last 2000 years. The synchronicity of multiple failures and their widespread distribution suggest a seismic origin that could be related to the nearby Gustaf-Lougheed Arch seismic zone. Further sedimentological investigations on the MMDs are however required to confirm their age and origin.
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This background brief looks into the new research and innovation strategy introduced by the European Union embodied in the Horizon 2020 funding programme. It focuses on the prospect for international collaboration in Horizon 2020, and presents a roadmap for both European institutions and those from key third countries to get ready for the opportunities provided by this funding instrument to embark on interesting research and innovation. The brief begins by outlining the efforts by the EU to address issues of economic competitiveness with a new growth strategy Europe 2020 in response to the enormous challenges faced by Europe in the midst of the debt crisis. It looks at the introduction of the Innovation Union as a Europe 2020 initiative, and explains how the new financial instrument, Horizon 2020, may be used to support the primary goals of more jobs, improved lives, better society and the global competitiveness of Europe. The brief also outlines the major differences of Horizon 2020 from the previous framework programmes, and recommends close collaboration between the European and the key third countries. The brief also proposes general and priority‐specific strategies for national research councils, universities and research institution to get ready to participate in the Horizon 2020 programme.