998 resultados para Air-coupled


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Specific properties emerge from the structure of large networks, such as that of worldwide air traffic, including a highly hierarchical node structure and multi-level small world sub-groups that strongly influence future dynamics. We have developed clustering methods to understand the form of these structures, to identify structural properties, and to evaluate the effects of these properties. Graph clustering methods are often constructed from different components: a metric, a clustering index, and a modularity measure to assess the quality of a clustering method. To understand the impact of each of these components on the clustering method, we explore and compare different combinations. These different combinations are used to compare multilevel clustering methods to delineate the effects of geographical distance, hubs, network densities, and bridges on worldwide air passenger traffic. The ultimate goal of this methodological research is to demonstrate evidence of combined effects in the development of an air traffic network. In fact, the network can be divided into different levels of âeurooecohesionâeuro, which can be qualified and measured by comparative studies (Newman, 2002; Guimera et al., 2005; Sales-Pardo et al., 2007).

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Rapport de synthèse Introduction : Le Glasgow coma score (GCS) est un outil reconnu permettant l'évaluation des patients après avoir subi un traumatisme crânien. Il est réputé pour sa simplicité et sa reproductibilité permettant ainsi aux soignants une évaluation appropriée et continue du status neurologique des patients. Le GCS est composé de trois catégories évaluant la réponse oculaire, verbale et motrice. En Suisse, les soins préhospitaliers aux patients victimes d'un trauma crânien sévère sont effectués par des médecins, essdntiellement à bord des hélicoptères médicalisés. Avant une anesthésie générale nécessaire à ces patients, une évaluation du GCS est essentielle indiquant au personnel hospitalier la gravité des lésions cérébrales. Afin d'évaluer la connaissance du GCS par les médecins à bord des hélicoptères médicalisés en Suisse, nous avons élaboré un questionnaire, contenant dans une première partie des questions sur les connaissances générales du GCS suivi d'un cas clinique. Objectif : Evaluation des connaissances pratiques et théoriques du GCS par les médecins travaillant à bord des hélicoptères médicalisés en Suisse. Méthode : Etude observationnelle prospective et anonymisée à l'aide d'un questionnaire. Evaluation des connaissances générales du GCS et de son utilisation clinique lors de la présentation d'un cas. Résultats : 16 des 18 bases d'hélicoptères médicalisés suisses ont participé à notre étude. 130 questionnaires ont été envoyés et le taux de réponse a été de 79.2%. Les connaissances théoriques du GCS étaient comparables pour tous les médecins indépendamment de leur niveau de formation. Des erreurs dans l'appréciation du cas clinique étaient présentes chez 36.9% des participants. 27.2% ont commis des erreurs dans le score moteur et 18.5% dans le score verbal. Les erreurs ont été répertoriées le plus fréquemment chez les médecins assistants (47.5%, p=0.09), suivi par les chefs de clinique (31.6%, p=0.67) et les médecins installés en cabinet (18.4%, p=1.00). Les médecins cadres ont fait significativement moins d'erreurs que les autres participants (0%, p<0.05). Aucune différence significative n'à été observée entre les différentes spécialités (anesthésie, médecine interne, médecine général et «autres »). Conclusion Même si les connaissances théoriques du GCS sont adéquates parmi les médecins travaillant à bord des hélicoptères médicalisés, des erreurs dans son application clinique sont présentes dans plus d'un tiers des cas. Les médecins avec le moins d'expériences professionnelle font le plus d'erreurs. Au vu de l'importance de l'évaluation correcte du score de Glasgow initial, une amélioration des connaissances est indispensable.

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An examination of the impact in the US and EU markets of two major innovations in the provision of air services on thin routes - regional jet technology and the low-cost business model - reveals significant differences. In the US, regional airlines monopolize a high proportion of thin routes, whereas low-cost carriers are dominant on these routes in Europe. Our results have different implications for business and leisure travelers, given that regional services provide a higher frequency of flights (at the expense of higher fares), while low-cost services offer lower fares (at the expense of lower flight frequencies). Keywords: air transportation; regional jet technology; low-cost business model; thin markets. JEL Classification Numbers: L13; L2; L93.

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Although exposure to secondhand smoke (SHS) is reportedly high in prison, few studies have measured this in the prison environment, and none have done so in Europe. We measured two indicators of SHS exposure (particulate matter PM10 and nicotine) in fixed locations before (2009) and after (2010) introduction of a partial smoking ban in a Swiss prison. Access to smoking cessation support was available to detainees throughout the study. Objectives To measure SHS before and after the introduction of a partial smoking ban. Methods Assessment of particulate matter PM10 (suspended microparticles of 10 μm) and nicotine in ambient air, collected by real-time aerosol monitor and nicotine monitoring devices. Results The authors observed a significant improvement of nicotine concentrations in the air after the introduction of the smoking ban (before: 7.0 μg/m(3), after: 2.1 μg/m(3), difference 4.9 μg/m(3), 95% CI for difference: 0.52 to 9.8, p=0.03) but not in particulate matter PM10 (before: 0.11 mg/m(3), after: 0.06 mg/m(3), difference 0.06 mg/m(3), 95% CI for difference of means: -0.07 to 0.19, p=0.30). Conclusions The partial smoking ban was followed by a decrease in nicotine concentrations in ambient air. These improvements can be attributed to the introduction of the smoking ban since no other policy change occurred during this period. Although this shows that concentrations of SHS decreased significantly, protection was still incomplete and further action is necessary to improve indoor air quality.

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Les sports équestres sont en plein développement en France où l'on compte plus d'un million de chevaux. Le nombre de cavaliers pratiquant en club ou chez eux est estimé à 600 000 et l'on dénombre plus de 68 000 emplois en France dans tous les domaines : agriculture, environnement, courses, loisirs, sports (www.haras-nationaux.fr). On trouve également dans les métiers du cheval les vétérinaires spécialisés ainsi que les maréchaux-ferrants. De plus, la France est un pays reconnu pour son activité d'élevage avec une production de chevaux de concours de très grande qualité.Récemment, plusieurs études relatant les expositions professionnelles à la poussière des écuries ont paru dans les journaux scientifiques. Les résultats montrent que la poussière issue des écuries contient, entre autres, des concentrations relativement élevées d'endotoxines (1) et de ?(1-3)-glucan (2) pouvant avoir des conséquences sur la santé respiratoire des travailleurs. En effet, des études précédentes ont montré que le fait de travailler ou de côtoyer des chevaux était associé avec une augmentation des risques de problèmes des voies respiratoires supérieures tels que des irritations du nez, de la toux (sèche et productive), de l'asthme, des bronchites chroniques et des épisodes d'" organic dust toxic syndrome (3) " (Gallagher et al., 2007 ; Mazan et al., 2009). [Auteure]

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The increase in mortality risk associated with long-term exposure to particulate air pollution is one of the most important, and best-characterised, effects of air pollution on health. This report presents estimates of the size of this effect on mortality in local authority areas in the UK, building upon the attributable fractions reported as an indicator in the public health outcomes framework for England. It discusses the concepts and assumptions underlying these calculations and gives information on how such estimates can be made. The estimates are expected to be useful to health and wellbeing boards when assessing local public health priorities, as well as to others working in the field of air quality and public health. The estimates of mortality burden are based on modelled annual average concentrations of fine particulate matter (PM2.5) in each local authority area originating from human activities. Local data on the adult population and adult mortality rates is also used. Central estimates of the fraction of mortality attributable to long-term exposure to current levels of anthropogenic (human-made) particulate air pollution range from around 2.5% in some local authorities in rural areas of Scotland and Northern Ireland and between 3 and 5% in Wales, to over 8% in some London boroughs. Because of uncertainty in the increase in mortality risk associated with ambient PM2.5, the actual burdens associated with these modelled concentrations could range from approximately one-sixth to about double these figures. Thus, current levels of particulate air pollution have a considerable impact on public health. Measures to reduce levels of particulate air pollution, or to reduce exposure of the population to such pollution, are regarded as an important public health initiative.

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In this study it was compared the MAS-100 and the Andersen air samplers' performances and a similar trend in both instruments was observed. It was also evaluated the microbial contamination levels in 3060 samples of offices, hospitals, industries, and shopping centers, in the period of 1998 to 2002, in Rio de Janeiro city. Considering each environment, 94.3 to 99.4% of the samples were the allowed limit in Brazil (750 CFU/m³). The industries' results showed more important similarity among fungi and total heterotrophs distributions, with the majority of the results between zero and 100 CFU/m³. The offices' results showed dispersion around 300 CFU/m³. The hospitals' results presented the same trend, with an average of 200 CFU/m³. Shopping centers' environments showed an average of 300 CFU/m³ for fungi, but presented a larger dispersion pattern for the total heterotrophs, with the highest average (1000 CFU/m³). It was also investigated the correlation of the sampling period with the number of airborne microorganisms and with the environmental parameters (temperature and air humidity) through the principal components analysis. All indoor air samples distributions were very similar. The temperature and air humidity had no significant influence on the samples dispersion patterns.

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Mutations of GPCRs can increase their constitutive (agonist-independent) activity. Some of these mutations have been artificially introduced by site-directed mutagenesis; others occur spontaneously in human diseases. The analysis of constitutively active GPCR mutants has attracted a large interest in the past decade, providing an important contribution to our understanding of the molecular mechanisms underlying receptor function and drug action.

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Introduction: Exposure to environmental tobacco smoke (ETS) is a major environmental risk factor. Indoor contaminants come from a variety of sources, which can include inadequate ventilation, volatile organic compounds (VOCs), biological agents, combustion products, and ETS. Because ETS is one of the most frequent causes of IAQ complaints as well as the high mortality of passive smoking, in June 2004 the University of Geneva made the decision to ban smoking inside the so called "Uni-Mail" building, the biggest Swiss University human science building of recent construction, and the ordinance was applied beginning in October 2004. This report presents the finding related to the IAQ of the "Uni-Mail" building before and after smoking bans using nicotine, suspended dust, condensate and PAHs level in air as tracers to perform an assessment of passive tobacco exposure for non-smokers inside the building. Methods: Respirable particles (RSP) A real time aerosol monitor (model DataRAM)was place at sampling post 1, level ground floor. Condensate It consists in extracting any organic matter taken on the glass fibre filters by MeOH, and then measuring the total absorbent of the MeOH extract to the UV wavelength of 447 nm. Nicotine Nicotine was taken by means of cartridges containing of XAD-4 to the fixed flow of 0.5 L/min. The analytical method used for the determination of nicotine is based on gas chromatography with Nitrogen selective detector GC-NPD. Results: Figure 1 shows the box plot density display of 3 parameters before and after smoking bans for all 7 sampling posts: dust, condensate and nicotine in air in μg/m3. Conclusion: Before the smoking ban, the level of the concentrations of respirable particles (RSP) is raised more, average of the day 320 μg/m3, with peaks of more than 1000 μg/m3, compared with the values of the surrounding air between 22 and 30 μg/m3. The nicotine level is definitely more important (average 5.53 μg/m3, field 1.5 to 17.9 μg/m3). Once the smoking bans inside the building were applied, one notes a clear improvement in terms of concentrations of pollutants. For dust, the concentration fell by 3 times (average: 130 μg/m3, range: 40 to 160 μg/m3) and that of nicotine by 10 times (average: 0.53 μg/m3, range: 0 to 1.69 μg/m3) compared to that found before smoking bans. The outdoor air RSP concentration was 22 μg/m3 or 10 times lower. Nicotine seems to be the best tracer for ETS free of interference, independent of location or season.

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Résumé Ce travail s'intéresse à la mise en oeuvre des politiques publiques visant à résoudre les problèmes engendrés par le développement de la mobilité urbaine. Nous adoptons sur cette dernière un point de vue nouveau, à savoir que l'enjeu de la régulation du trafic est d'abord celui de la maîtrise des usages nombreux et conflictuels sur deux ressources collectives, l'air et les voies publiques. Pour comprendre comment ces usages sont régulés, nous mobilisons les deux apports théoriques de l'économie institutionnelle (Bromley 1991, Devlin et Grafton 1990, Ostrom 1990, 2000) et de l'analyse des politiques publiques (Knoepfel et al. 2001) au sein du cadre d'analyse des régimes institutionnels de ressources collectives. La première problématise la difficulté de définir des règles communes d'usage pour éviter la surexploitation des ressources alors que la seconde met en jeu notamment le problème de la coordination des politiques publiques d'exploitation et de protection de l'environnement. Sur ce socle, nous choisissons de retenir une approche « institutionnaliste centrée sur les acteurs » (Scharpf 1997), aussi thématisée par les approches néo-institutionnalistes (Hall/Taylor 1996, March/Olsen 1989) visant à expliquer le changement politique par deux types de variables explicatives, à savoir les changements dans la régulation publique (variable institutionnelle) et les changements de la configuration des acteurs en présence, à partir desquels nous bâtissons nos hypothèses de recherche. En l'espèce, l'étude mobilise la variable explicative des régimes institutionnels de l'air et du sol mobilisés par les acteurs de la mobilité pour comprendre l'évolution de la répartition des usages sur les routes urbaines. Ce processus passe par le recours à des ressources de politiques publiques comme le droit, l'argent, l'information, le consensus, le soutien politique, l'infrastructure ou le temps que les acteurs peuvent activer en fonction des règles institutionnelles en présence. On peut classer ces dernières d'abord selon leur niveau de généralité (niveaux opérationnel, des choix collectifs et constitutionnel - Ostrom 1990). L'étude établit que la régulation des usages connaît une importante gradation que rend compte le concept de résistance normative. En fonction de cette dernière, les acteurs essaient de s'imposer au moyen de deux dimensions des règles, que ce travail met en exergue, à savoir selon qu'elles régulent tantôt le mode de décision tantôt le mode d'appropriation. Ces règles décisionnelles et possessionnelles déterminent les possibilités d'accès, ainsi que la procédure d'intervention et la place qui sont réservées aux acteurs, aussi bien pour les ressources collectives physiques que de politique publique. L'étude permet ainsi à la fois d'apporter des éléments nouveaux à la théorie des changements de régimes institutionnels de ressources collectives, d'éclairer un peu plus les processus de mise en couvre de l'action publique et de contribuer au débat sur les principales propositions permettant de maîtriser les impacts négatifs du développement de la mobilité.

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The idea that a receptor can produce signalling without agonist intervention and that several antagonists can be 'active' in repressing such spontaneous activity is contained in the concept of ligand-induced conformational changes. Yet, this idea was neglected by pharmacologists for many years. In this article, we review the events that brought inverse agonism and constitutive activity to general attention and made this phenomenon a topic of current research. We also suggest a classification of antagonists based on the cooperativity that links their primary site of interaction with other functional domains of the receptor.

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Background Maternal exposure to air pollution has been related to fetal growth in a number of recent scientific studies. The objective of this study was to assess the association between exposure to air pollution during pregnancy and anthropometric measures at birth in a cohort in Valencia, Spain. Methods Seven hundred and eighty-five pregnant women and their singleton newborns participated in the study. Exposure to ambient nitrogen dioxide (NO2) was estimated by means of land use regression. NO2 spatial estimations were adjusted to correspond to relevant pregnancy periods (whole pregnancy and trimesters) for each woman. Outcome variables were birth weight, length, and head circumference (HC), along with being small for gestational age (SGA). The association between exposure to residential outdoor NO2 and outcomes was assessed controlling for potential confounders and examining the shape of the relationship using generalized additive models (GAM). Results For continuous anthropometric measures, GAM indicated a change in slope at NO2 concentrations of around 40 μg/m3. NO2 exposure >40 μg/m3 during the first trimester was associated with a change in birth length of -0.27 cm (95% CI: -0.51 to -0.03) and with a change in birth weight of -40.3 grams (-96.3 to 15.6); the same exposure throughout the whole pregnancy was associated with a change in birth HC of -0.17 cm (-0.34 to -0.003). The shape of the relation was seen to be roughly linear for the risk of being SGA. A 10 μg/m3 increase in NO2 during the second trimester was associated with being SGA-weight, odds ratio (OR): 1.37 (1.01-1.85). For SGA-length the estimate for the same comparison was OR: 1.42 (0.89-2.25). Conclusions Prenatal exposure to traffic-related air pollution may reduce fetal growth. Findings from this study provide further evidence of the need for developing strategies to reduce air pollution in order to prevent risks to fetal health and development.