975 resultados para Born globals


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En aquest projecte s’ha analitzat i optimitzat l’enllaç satèl·lit amb avió per a un sistema aeronàutic global. Aquest nou sistema anomenat ANTARES està dissenyat per a comunicar avions amb estacions base mitjançant un satèl·lit. Aquesta és una iniciativa on hi participen institucions oficials en l’aviació com ara l’ECAC i que és desenvolupat en una col·laboració europea d’universitats i empreses. El treball dut a terme en el projecte compren bàsicament tres aspectes. El disseny i anàlisi de la gestió de recursos. La idoneïtat d’utilitzar correcció d’errors en la capa d’enllaç i en cas que sigui necessària dissenyar una opció de codificació preliminar. Finalment, estudiar i analitzar l’efecte de la interferència co-canal en sistemes multifeix. Tots aquests temes són considerats només per al “forward link”. L’estructura que segueix el projecte és primer presentar les característiques globals del sistema, després centrar-se i analitzar els temes mencionats per a poder donar resultats i extreure conclusions.

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Amb la finalitat de conèixer l’estat de qualitat de les aigües de les basses i pous del Parc del Garraf, s’analitzen una sèrie de paràmetres fisico-químics en 17 estacions de mostreig prèviament seleccionades, distribuïdes en zones amb diferents tipologies d’ús del sòl. La base de l’anàlisi ha estat la integració d’informació provinent de diferents fonts. Mitjançant l’elaboració de taules i gràfics, la generació de cartografia i el tractament estadístic de les dades, s’ha procedit a la tria de punts de mostreig i s’ha obtingut un inventari que ha permès la interpretació global dels resultats, facilitant la diagnosi. El procés de tractament de dades inclou la confecció d’un índex de qualitat de les aigües (ICA) propi, no vinculant, a partir de fórmules genèriques de normalització i ponderació de valors. Durant la realització de la diagnosi s’han detectat pertorbacions puntuals en determinats paràmetres corresponents a contaminacions locals, en diferents estacions de mostreig. Aquestes pertorbacions s’han relacionat amb la situació dels pous i les basses al Garraf i les tipologies d’ús del sòl de cada zona. El diagnòstic de pertorbacions ha orientat les propostes de millora aplicables que s’han dividit en tres classes segons el nivell d’actuació. Aquestes incideixen principalment, en la millora de la informació disponible, l’aplicació de l’agricultura ecològica, l’explotació sostenible dels aqüífers i la realització d’estudis globals i/o locals, més complets i exhaustius.

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Adverse events in utero are associated with the occurrence of chronic diseases in adulthood. We previously demonstrated in mice that perinatal hypoxia resulted in altered pulmonary circulation in adulthood, with a decreased endothelium-dependent relaxation of pulmonary arteries, associated with long-term alterations in the nitric oxide (NO)/cyclic GMP pathway. The present study investigated whether inhaled NO (iNO) administered simultaneously to perinatal hypoxia could have potential beneficial effects on the adult pulmonary circulation. Indeed, iNO is the therapy of choice in humans presenting neonatal pulmonary hypertension. Long-term effects of neonatal iNO therapy on adult pulmonary circulation have not yet been investigated. Pregnant mice were placed in hypoxia (13% O2) with simultaneous administration of iNO 5 days before delivery until 5 days after birth. Pups were then raised in normoxia until adulthood. Perinatal iNO administration completely restored acetylcholine-induced relaxation, as well as endothelial nitric oxide synthase protein content, in isolated pulmonary arteries of adult mice born in hypoxia. Right ventricular hypertrophy observed in old mice born in hypoxia compared to controls was also prevented by perinatal iNO treatment. Therefore, simultaneous administration of iNO during perinatal hypoxic exposure seems able to prevent adverse effects of perinatal hypoxia on the adult pulmonary circulation.

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In the recent years most libraries have focused on mass digitization programs and keeping electronic born documents, showing and organizing them in a repository. While those repositories have evolved to a much more manageable systems focusing on the user expectations and introducing web 2.0 tools, digital preservation is still in the to-do list of most of them. There is quite a lot of studies focused on preservation and some complex models exist, unfortunately, very few practical systems are running and its quite difficult for a library to get involved in a solution already tested by others. The CBUC (Consortium of University Catalan Libraries) runs TDX, an ETD repository now keeping more than 10.000 full text thesis from any of the 12 university members. After 10 years running TDX a solid preservation system was needed to ensure every thesis would be kept as it was regardless what happens to the repository. The perfect solution was found in the MetaArchive cooperative, this is the effort of many insitutions to keep a copy of each other content through a newtwork using the LOCKSS software as a mechanism to keep track of any change. The presentation will shortly introduce what TDX and MetaArchive is but will, in a practical way, show how the LOCKSS network for presrervation works. Finally a summary of the benefits of the overall experience will be shown.

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It is anticipated that one out of 3 children born in the year 2000 in the United States may develop diabetes. In Switzerland, a population based study in the city of Lausanne (CoLaus) has shown that about 30% of the participants have abnormal glucose homeostasis, and that the prevalence of obesity in the younger age groups has doubled since 1992. In this review, we describe clinical and biological factors associated with an increased risk to develop diabetes and summarize the most important intervention studies that have shown a beneficial effect in the prevention of diabetes. While life style modifications should be recommended for everybody, the place of pharmacological interventions (oral hypoglycemic agents, blood pressure and cholesterol lowering agents) is more controversial.

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A cross-sectional survey conducted among evening students was used to determine the prevalence of Wuchereria bancrofti infection in Maceió, capital of the State of Alagoas, northeast Brazil. A single thick-blood smear was used, being collected between 10 p.m. and 12 a.m. From a total of 29,551 students enrolled at evening elementary schools in the 33 city sectors, 16,569 (56.4%) were random selected for inclusion in the study. From those, 10,857 (65.5%) were interviewed and examined and 73 (0.7%) were found to have microfilaraemia. Autochthonous W. bancrofti carriers live in 10 of the 33 city sectors, suggesting a focal distribution. Moreover, 84% of infections were diagnosed among 29% of all students examined, inhabiting three contiguous sectors at the city central area, presenting infection rates up to 5.3%. Students living in city sectors with prevalence of microfilariae carriers greater than 1% were found to have a higher risk for infection when compared to students from the rest of the town [Relative Odds (RO) 12.8, 95% CI 6.7 - 25.1]. Eleven positive individuals from non endemic areas were living in Maceió for more than 10 years; time of residence in the area was a major risk factor for infection among students not born in the region (p<0.01). Regarding sex, male students presented a higher proportion of positive (RO 1.7, 95% CI 1.1 - 2.9).

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A stable microbial system in the respiratory tract acts as an important defense mechanism against pathogenic microorganisms. Perturbations in this system may allow pathogens to establish. In an ecological environment such as the respiratory tract, there are many diverse factors that play a role in the establishment of the indigenous flora. In the present work we studied the normal microbial flora of different areas of the respiratory tract of mice and their evolution from the time the mice were born. Our interest was to know which were the dominant groups of microorganisms in each area, which were the first capable of colonizing and which dominated over time to be used as probiotic microorganisms. Our results show that Gram negative facultatively anaerobic bacilli and strict anaerobic microorganisms were the last ones to appear in the bronchia, while aerobic and Gram positive cocci were present in all the areas of the respiratory tract. The number of facultative aerobes and strict anaerobes were similar in the nasal passage, pharynx instilled and trachea, but lower in bronchia. The dominant species were Streptococcus viridans and Staphylococcus saprophyticcus, followed by S. epidermidis, Lactobacilli and S. cohnii I which were present on every studied days but at different proportions. This paper is the first part of a research topic investigating the protective effect of the indigenous flora against pathogens using the mice as an experimental model.

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In several colour polymorphic species, morphs differ in thermoregulation either because dark and pale surfaces absorb solar radiation to a different extent and/or because morphs differ in key metabolic processes. Morph-specific thermoregulation may potentially account for the observation that differently coloured individuals are frequently not randomly distributed among habitats, and differ in many respects, including behaviour, morphology, survival and reproductive success. In a wild population of the colour polymorphic tawny owl Strix aluco, a recent cross-fostering experiment showed that offspring raised and born from red mothers were heavier than those from grey mothers. In the present study, we tested in the same individuals whether these morph-specific offspring growth patterns were associated with a difference in metabolic rate between offspring of red and grey mothers. For this purpose, we measured nestling oxygen consumption under two different temperatures (laboratory measurements: 4 and 20 degrees C), and examined the relationships between these data sets and the colour morph of foster and biological mothers. After controlling for nestling body mass, oxygen consumption at 20 degrees C was greater in foster offspring raised by grey foster mothers. No relationship was found between nestling oxygen consumption and coloration of their biological mother. Therefore, our study indicates that in our experiment offspring raised by grey foster mothers showed not only a lower body mass than offspring raised by red foster mothers, but also consumed more oxygen under warm temperature. This further indicates that rearing conditions in nests of grey mothers were more stressful than in nests of red mothers.

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Aquest treball documenta l’estada a Barcelona, entre el 1794 i 1798, dels germans Joseph i Peter Petrides, trompistes nascuts a Praga. L’excepcional trajectòria d’ambdós a la capital catalana, com a membres de l’orquestra del Teatre de la Santa Creu i com a solistes destacats, il·lustra el desenvolupament de l’ofici de músic a la ciutat durant l’última dècada del segle XVIII.

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Aquest projecte intenta implantar una metodologia de treball sobre MATE. MATE es una eina de sintonització d'aplicacions paral·leles sorgida de la tesis doctoral d'Anna Sikora a 2003. Vistos els resultats obtinguts, es va decidir donar un pas endavant i convertir-la en un producte software Open Source. Per fer-ho ha sigut necessari aplicar una serie d'estàndards i fer un proces de tests. En aquest treball s'ha creat part de la metodologia i s'han modificat dos dels mòduls principals.

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El canvi climàtic del segle XXI és una realitat, hi ha moltes evidències científiques que indiquen que l’escalfament del sistema climàtic és inequívoc. Malgrat això, també hi ha moltes incerteses respecte els impactes que pot comportar aquest canvi climàtic global. L’objectiu d’aquest projecte és estudiar la possible evolució futura de tres variables climàtiques, que són el rang de la temperatura diürna a prop de la superfície (DTR), la temperatura mitjana a prop de la superfície (MT) i la precipitació mensual (PL_mes) i valorar l’exposició que poden experimentar diferents cobertes del sòl i diferents regions biogeogràfiques del continent europeu davant d’aquests possibles patrons de canvi. Per això s’han utilitzat Models Climàtics Globals que fan projeccions de variables climàtiques que permeten preveure el possible clima futur. Mitjançant l’aplicatiu informàtic Tetyn s’han extret els paràmetres climàtics dels conjunts de dades del Tyndall Centre for Climate Change Research, del futur (TYN SC) i del passat (CRU TS). Les variables obtingudes s’han processat amb eines de sistemes d’informació geogràfica (SIG) per obtenir els patrons de canvi de les variables a cada coberta del sòl. Els resultats obtinguts mostren que hi ha una gran variabilitat, que augmenta amb el temps, entre els diferents models climàtics i escenaris considerats, que posa de manifest la incertesa associada a la modelització climàtica, a la generació d’escenaris d’emissions i a la naturalesa dinàmica i no determinista del sistema climàtic. Però en general, mostren que les glaceres seran una de les cobertes més exposades al canvi climàtic, i la mediterrània, una de les regions més vulnerables

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Résumé Même si l'incidence de la tuberculose est basse en Suisse, cette maladie reste un problème de santé publique en raison des migrations de populations provenant de pays où l'incidence de la tuberculose est élevée. Les immigrants, à leur arrivée en terre helvétique, doivent s'annoncer auprès d'un des cinq centres d'enregistrement pour les réfugiés (Vallorbe, Bâle, Kreuzlingen, Altstätten et Chiasso) et subir un contrôle médical qui comprend un test tuberculinique et une radiographie du thorax afin de détecter des anomalies compatibles avec une tuberculose. Les requérants avec des signes de maladie sont immédiatement pris en charge dans le but d'éviter une dissémination du bacille de Koch. Cette* étude rétrospective compare la présentation bactériologique et clinique de la tuberculose ainsi que le résultat du traitement de cette maladie chez les immigrants diagnostiqués par dépistage actif (= immigrants venant d'être enregistrés comme requérants d'asile en Suisse) avec d'autres patients diagnostiqués par dépistage passif (= patients suisses, travailleurs étrangers résidents en Suisse ainsi que d'autres étrangers incluant les touristes, les étudiants, les immigrants illégaux ainsi que 11 requérants d'asile détectés tardivement et passivement après leur entrée en Suisse). Parmi les 179 patients, 78% sont des étrangers. La médiane d'âge de la population étrangère atteinte de tuberculose est de 29 ans contre 64 ans pour les Suisses. Le dépistage actif a été effectué auprès de 71 requérants d'asile chez lesquels 49.3% [CI : 37.4 - 61.2] n'avaient pas de symptômes contre 17.6% [Cl : 10.3 - 24.9] chez les 108 passifs. La durée des symptômes était de 2 mois dans le groupe des actifs versus 2.5 mois chez les passifs (ns). L'analyse bactériologique est positive à l'examen direct ou à la culture chez 63.4% des actifs contre 70.4% des passifs (ns). La confirmation bactériologique de la tuberculose chez des patients asymptomatiques s'élevait à 42.2% [Cl : 27.2-57.2] chez les actifs contre 13% [Cl : 5.31-20.7] chez les passifs. Le plus grand danger de dissémination est couru par les patients avec un examen direct positif dont la proportion des asymptomatiques était de 22.2% ([Cl : 9.6-34.8] dans le groupe des actifs contre 11.7% [CI : 4.4-19.0] dans le groupe des passifs. Le résultat du traitement, comprenant les patients guéris (avec confirmation bactériologique de guérison) ainsi que les patients ayant accompli le traitement jusqu'à la fin (mais sans confirmation bactériologique) est similaire dans les groupes des actifs et passifs. Le résultat différent selon le statut légal avec 88% pour les travailleurs étrangers, 85% pour les Suisses, 78% pour les autres étrangers et 83% pour les réfugiés. Ces chiffres sont proches des cibles de l'OMS (85%). Le dépistage actif de la tuberculose permet la détection plus précoce des cas de tuberculose que le dépistage passif. Etant donné que les immigrants proviennent de régions où la prévalence de la tuberculose est supérieure à celle de la Suisse, ce dépistage à la frontière permet non seulement de diminuer la dissémination de cette maladie par la prise en charge immédiate des malades et de réduire la durée des symptômes mais encore de détecter des patients ne présentant aucun symptôme malgré une activité bactériologique positive. Les résultats du traitement ne satisfont pas entièrement aux exigences de l'OMS, ce qui peut être expliqué par le fait que la population de patients tuberculeux suisses étant plus âgés que celles des étrangers, le nombre de décès est plus nombreux (soit par la tuberculose, soit par les complications de maladies sous-jacentes) et que le suivi de patients étrangers est plus difficile car certains disparaissent durant le traitement et d'autres sont transférés ailleurs en Suisse ou retournent dans leur pays. Summary Aim: This retrospective study compared the bacteriological and clinical presentation of tuberculosis and the outcome of treatment in immigrant notified for TB after active screening by chest X-ray at the border with other patients detected by passive screening. Design: Retrospective study of all patients notified for TB in Vaud Canton in 2001 and 2002. Result: In Vaud Canton 78% of the 179 patients notified for TB were foreign-born. Among 71 asylum seekers actively screened at the border, 49.3% [CI 37.4 - 61.2] were symptom-free vs 17.6% [CI 10.3 - 24.9] among 108 passively screened patients. In the passively screened group, the proportion of asymptomatic patients was 15.4% for Swiss patients. 8.6% for foreign workers, and 29.4% for other foreigners. The average duration of symptoms before diagnosis among patients with complaints was 2 months in actively screened foreign-born, compared to 2.5 months in passively screened patients (no significant difference by Wilcoxon-Mann-Whitney test). The proportion of pulmonary TB cases with positive smear or culture was 63.4% in actively screened patients vs 70.4% in passively detected cases. Among actively screened patients with bacteriological confirmation, 42.2% [CI 27.2-57,2] were asymptomatic compared to 13% [CI 5.31-20.7] for passively screened patients. Considering only smear positive patients, the proportion of symptom-free patients was 22.2% [CI 9.6-34.8] in 45 actively screened cases vs 11-7% [4.4 - 19.0] for 77 passive screening. Cure and treatment completion rate for new cases reached 88% for foreign workers, 83% for asylum seekers, 85% for Swiss patients, 78% for other foreigners. Conclusions: Actively screened patients were more frequently asymptomatic than passively detected cases, even when considering only patients with bacteriological confirmation. The active screening by chest X-ray of an immigrant population with a high prevalence of tuberculosis allows the early detection and treatment of tuberculosis. This may contribute to the protection of the resident population for infection. The outcome of treatment for tuberculosis was satisfactory in all population groups.

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Distinct Toxoplasma gondii antigens were entrapped within liposomes and evaluated for their ability to protect Balb/c mice against congenital transmission: soluble tachyzoite antigen (L/STAg), soluble tissue cyst antigen (L/SCAg), soluble tachyzoite plus tissue cyst (L/STCAg) or purified 32kDa antigen of tachyzoite (L/pTAg). Soluble tachyzoite antigen alone in PBS (STAg) or emulsified in Freund's Complete Adjuvant (FCA/STAg) was also evaluated. Dams were inoculated subcutaneously with these antigens 6, 4 and 2 weeks prior to a challenge with four tissue cysts of the P strain of T. gondii orally between 10 and 14 days of pregnancy. Significant diminution differences were observed between the frequency of infected pups born of the dams immunized with the antigens incorporated into liposomes and that of pups born of the dams immunized with antigen emulsified in FCA or non immunized group (p<0.05). There was a significant decrease in the number of pups born dead in the groups L/STAg, L/SCAg and L/pTAg when compared with pups from all other groups (p <0.05). All dams immunized with or without adjuvant showed an antibody response and a proliferation of T-cells. However, no correlation was found between immune response and protection against the challenge.

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Recognition by the T-cell receptor (TCR) of immunogenic peptides (p) presented by Class I major histocompatibility complexes (MHC) is the key event in the immune response against virus-infected cells or tumor cells. A study of the 2C TCR/SIYR/H-2K(b) system using a computational alanine scanning and a much faster binding free energy decomposition based on the Molecular Mechanics-Generalized Born Surface Area (MM-GBSA) method is presented. The results show that the TCR-p-MHC binding free energy decomposition using this approach and including entropic terms provides a detailed and reliable description of the interactions between the molecules at an atomistic level. Comparison of the decomposition results with experimentally determined activity differences for alanine mutants yields a correlation of 0.67 when the entropy is neglected and 0.72 when the entropy is taken into account. Similarly, comparison of experimental activities with variations in binding free energies determined by computational alanine scanning yields correlations of 0.72 and 0.74 when the entropy is neglected or taken into account, respectively. Some key interactions for the TCR-p-MHC binding are analyzed and some possible side chains replacements are proposed in the context of TCR protein engineering. In addition, a comparison of the two theoretical approaches for estimating the role of each side chain in the complexation is given, and a new ad hoc approach to decompose the vibrational entropy term into atomic contributions, the linear decomposition of the vibrational entropy (LDVE), is introduced. The latter allows the rapid calculation of the entropic contribution of interesting side chains to the binding. This new method is based on the idea that the most important contributions to the vibrational entropy of a molecule originate from residues that contribute most to the vibrational amplitude of the normal modes. The LDVE approach is shown to provide results very similar to those of the exact but highly computationally demanding method.

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A 6 1/2-year-old girl had developmental regression, and Leigh syndrome was diagnosed. A second girl born to the same mother after heterologous artificial insemination also lost acquired skills and died at 2 1/2 years of age; neuropathologic examination confirmed the diagnosis of Leigh syndrome. Tissues from both children and from the mother had a point mutation at nucleotide 8993 in the adenosinetriphosphatase 6-gene of mitochondrial DNA. This family illustrates that Leigh syndrome can be transmitted by maternal inheritance.