Méthodes sismiques actives adaptées à l'étude de milieux hétérogènes : application aux glissements de terrain

Résumé Les glissements de terrain représentent un des principaux risques naturels dans les régions montagneuses. En Suisse, chaque année les glissements de terrains causent des dégâts qui affectent les infrastructures et ont des coûts financiers importants. Une bonne compréhension des mécanismes des glissements peut permettre d'atténuer leur impact. Celle-ci passe notamment par la connaissance de la structure interne du glissement, la détermination de son volume et de son ou ses plans de glissement. Dans un glissement de terrain, la désorganisation et la présence de fractures dans le matériel déplacé engendre un changement des paramètres physiques et en particulier une diminution des vitesses de propagation des ondes sismiques ainsi que de la densité du matériel. Les méthodes sismiques sont de ce fait bien adaptées à l'étude des glissements de terrain. Parmi les méthodes sismiques, l'analyse de la dispersion des ondes de surface est une méthode simple à mettre en oeuvre. Elle présente l'avantage d'estimer les variations des vitesses de cisaillement avec la profondeur sans avoir spécifiquement recours à l'utilisation d'une source d'onde S et de géophones horizontaux. Sa mise en oeuvre en trois étapes implique la mesure de la dispersion des ondes de surface sur des réseaux étendus, la détermination des courbes de dispersion pour finir par l'inversion de ces courbes. Les modèles de vitesse obtenus à partir de cette procédure ne sont valides que lorsque les milieux explorés ne présentent pas de variations latérales. En pratique cette hypothèse est rarement vérifiée, notamment pour un glissement de terrain dans lequel les couches remaniées sont susceptibles de présenter de fortes hétérogénéités latérales. Pour évaluer la possibilité de déterminer des courbes de dispersion à partir de réseaux de faible extension des mesures testes ont été effectuées sur un site (Arnex, VD) équipé d'un forage. Un profil sismique de 190 m de long a été implanté dans une vallée creusée dans du calcaire et remplie par des dépôts glacio-lacustres d'une trentaine de mètres d'épaisseur. Les données acquises le long de ce profil ont confirmé que la présence de variations latérales sous le réseau de géophones affecte l'allure des courbes de dispersion jusqu'à parfois empêcher leur détermination. Pour utiliser l'analyse de la dispersion des ondes de surface sur des sites présentant des variations latérales, notre approche consiste à déterminer les courbes de dispersions pour une série de réseaux de faible extension, à inverser chacune des courbes et à interpoler les différents modèles de vitesse obtenus. Le choix de la position ainsi que de l'extension des différents réseaux de géophones est important. Il tient compte de la localisation des hétérogénéités détectées à partir de l'analyse de sismique réfraction, mais également d'anomalies d'amplitudes observées sur des cartes qui représentent dans le domaine position de tir - position du récepteur, l'amplitude mesurée pour différentes fréquences. La procédure proposée par Lin et Lin (2007) s'est avérée être une méthode efficace permettant de déterminer des courbes de dispersion à partir de réseaux de faible extension. Elle consiste à construire à partir d'un réseau de géophones et de plusieurs positions de tir un enregistrement temps-déports qui tient compte d'une large gamme de distances source-récepteur. Au moment d'assembler les différentes données une correction de phase est appliquée pour tenir compte des hétérogénéités situées entre les différents points de tir. Pour évaluer cette correction nous suggérons de calculer pour deux tir successif la densité spectrale croisée des traces de même offset: Sur le site d'Arnex, 22 courbes de dispersions ont été déterminées pour de réseaux de géophones de 10 m d'extension. Nous avons également profité du forage pour acquérir un profil de sismique verticale en ondes S. Le modèle de vitesse S déduit de l'interprétation du profil de sismique verticale est utilisé comme information à priori lors l'inversion des différentes courbes de dispersion. Finalement, le modèle en deux dimension qui a été établi grâce à l'analyse de la dispersion des ondes de surface met en évidence une structure tabulaire à trois couches dont les limites coïncident bien avec les limites lithologiques observées dans le forage. Dans celui-ci des argiles limoneuses associées à une vitesse de propagation des ondes S de l'ordre de 175 m/s surmontent vers 9 m de profondeur des dépôts de moraine argilo-sableuse caractérisés par des vitesses de propagation des ondes S de l'ordre de 300 m/s jusqu'à 14 m de profondeur et supérieur ou égal à 400 m/s entre 14 et 20 m de profondeur. Le glissement de la Grande Combe (Ballaigues, VD) se produit à l'intérieur du remplissage quaternaire d'une combe creusée dans des calcaires Portlandien. Comme dans le cas du site d'Arnex les dépôts quaternaires correspondent à des dépôts glacio-lacustres. Dans la partie supérieure la surface de glissement a été localisée à une vingtaine de mètres de profondeur au niveau de l'interface qui sépare des dépôts de moraine jurassienne et des dépôts glacio-lacustres. Au pied du glissement 14 courbes de dispersions ont été déterminées sur des réseaux de 10 m d'extension le long d'un profil de 144 m. Les courbes obtenues sont discontinues et définies pour un domaine de fréquence de 7 à 35 Hz. Grâce à l'utilisation de distances source-récepteur entre 8 et 72 m, 2 à 4 modes de propagation ont été identifiés pour chacune des courbes. Lors de l'inversion des courbes de dispersion la prise en compte des différents modes de propagation a permis d'étendre la profondeur d'investigation jusqu'à une vingtaine de mètres de profondeur. Le modèle en deux dimensions permet de distinguer 4 couches (Vs1 < 175 m/s, 175 m/s < Vs2 < 225 m/s, 225 m/s < Vs3 < 400 m/s et Vs4 >.400 m/s) qui présentent des variations d'épaisseur. Des profils de sismiques réflexion en ondes S acquis avec une source construite dans le cadre de ce travail, complètent et corroborent le modèle établi à partir de l'analyse de la dispersion des ondes de surface. Un réflecteur localisé entre 5 et 10 m de profondeur et associé à une vitesse de sommation de 180 m/s souligne notamment la géométrie de l'interface qui sépare la deuxième de la troisième couche du modèle établi à partir de l'analyse de la dispersion des ondes de surface. Abstract Landslides are one of the main natural hazards in mountainous regions. In Switzerland, landslides cause damages every year that impact infrastructures and have important financial costs. In depth understanding of sliding mechanisms may help limiting their impact. In particular, this can be achieved through a better knowledge of the internal structure of the landslide, the determination of its volume and its sliding surface or surfaces In a landslide, the disorganization and the presence of fractures in the displaced material generate a change of the physical parameters and in particular a decrease of the seismic velocities and of the material density. Therefoe, seismic methods are well adapted to the study of landslides. Among seismic methods, surface-wave dispersion analysis is a easy to implement. Through it, shearwave velocity variations with depth can be estimated without having to resort to an S-wave source and to horizontal geophones. Its 3-step implementation implies measurement of surface-wave dispersion with long arrays, determination of the dispersion curves and finally inversion of these curves. Velocity models obtained through this approach are only valid when the investigated medium does not include lateral variations. In practice, this assumption is seldom correct, in particular for landslides in which reshaped layers likely include strong lateral heterogeneities. To assess the possibility of determining dispersion curves from short array lengths we carried out tests measurements on a site (Arnex, VD) that includes a borehole. A 190 m long seismic profile was acquired in a valley carved into limestone and filled with 30 m of glacio-lacustrine sediments. The data acquired along this profile confirmed that the presence of lateral variations under the geophone array influences the dispersion-curve shape so much that it sometimes preventes the dispersion curves determination. Our approach to use the analysis of surface-wave dispersion on sites that include lateral variations consists in obtaining dispersion curves for a series of short length arrays; inverting each so obtained curve and interpolating the different obtained velocity model. The choice of the location as well as the geophone array length is important. It takes into account the location of the heterogeneities that are revealed by the seismic refraction interpretation of the data but also, the location of signal amplitude anomalies observed on maps that represent, for a given frequency, the measured amplitude in the shot position - receiver position domain. The procedure proposed by Lin and Lin (2007) turned out to be an efficient one to determine dispersion curves using short extension arrays. It consists in building a time-offset from an array of geophones with a wide offset range by gathering seismograms acquired with different source-to-receiver offsets. When assembling the different data, a phase correction is applied in order to reduce static phase error induced by lateral variation. To evaluate this correction, we suggest to calculate, for two successive shots, the cross power spectral density of common offset traces. On the Arnex site, 22 curves were determined with 10m in length geophone-arrays. We also took advantage of the borehole to acquire a S-wave vertical seismic profile. The S-wave velocity depth model derived from the vertical seismic profile interpretation is used as prior information in the inversion of the dispersion-curves. Finally a 2D velocity model was established from the analysis of the different dispersion curves. It reveals a 3-layer structure in good agreement with the observed lithologies in the borehole. In it a clay layer with a shear-wave of 175 m/s shear-wave velocity overlies a clayey-sandy till layer at 9 m depth that is characterized down to 14 m by a 300 m/s S-wave velocity; these deposits have a S-wave velocity of 400 m/s between depths of 14 to 20 m. The La Grand Combe landslide (Ballaigues, VD) occurs inside the Quaternary filling of a valley carved into Portlandien limestone. As at the Arnex site, the Quaternary deposits correspond to glaciolacustrine sediments. In the upper part of the landslide, the sliding surface is located at a depth of about 20 m that coincides with the discontinuity between Jurassian till and glacio-lacustrine deposits. At the toe of the landslide, we defined 14 dispersion curves along a 144 m long profile using 10 m long geophone arrays. The obtained curves are discontinuous and defined within a frequency range of 7 to 35 Hz. The use of a wide range of offsets (from 8 to 72 m) enabled us to determine 2 to 4 mode of propagation for each dispersion curve. Taking these higher modes into consideration for dispersion curve inversion allowed us to reach an investigation depth of about 20 m. A four layer 2D model was derived (Vs1< 175 m/s, 175 m/s <Vs2< 225 m/s, 225 m/s < Vs3 < 400 m/s, Vs4> 400 m/s) with variable layer thicknesses. S-wave seismic reflection profiles acquired with a source built as part of this work complete and the velocity model revealed by surface-wave analysis. In particular, reflector at a depth of 5 to 10 m associated with a 180 m/s stacking velocity image the geometry of the discontinuity between the second and third layer of the model derived from the surface-wave dispersion analysis.

Incorporating waiting time in competitive location models: formulations and heuristics

In this paper we propose a metaheuristic to solve a new version of the Maximum Capture Problem. In the original MCP, market capture is obtained by lower traveling distances or lower traveling time, in this new version not only the traveling time but also the waiting time will affect the market share. This problem is hard to solve using standard optimization techniques. Metaheuristics are shown to offer accurate results within acceptable computing times.

Health education of diabetes as a chronic disease : transmission of information or active appropriation ?

Résumé du poster : Diabetes is both an important chronic disease and a real public health problem. It requires a great control over the body and a great mastery of the tools used in the daily struggle to reach a physiological balance. It is therefore a disease in which health education plays an important role, since patients are expected to reach a certain autonomy in the management of their disease. But how can the patients' autonomy be promoted? This is the question to which this study tried to answer from the perspective of socio-cultural psychology. The study was launched by the Cantonal Diabetes Program Vaud and aimed at evaluating a health education setting located in the east region of the Canton Vaud. It was based on both quantitative and qualitative methodological approaches. The results showed that there is a correlation between the number of hospitalizations and the quality of support provided by this particular health education setting. Moreover, the acquisition of expertise appears to be a distributed and collective process based upon the actors' active participation in various types of activities and involving and extended network. Further research is now required in order to examine how health education might be grasped through the lens of social-cultural psychology.

Metodologia de Análise de Investimentos em Sistemas e Tecnologias da Informação, pelas empresas caboverdeanas

O aumento da competitividade das empresas caboverdeanas impõe-se sobretudo por causa do momento histórico que particularmente o país atravessa. A graduação para país de rendimento médio, a adesão à Organização Mundial de Comércio e o estatuto de parceria especial com a União Europeia constituem razões de grande vulto para as empresas nacionais e outras que empreendem no mercado caboverdeano, definirem eficazmente e eficientemente os seus processos organizacionais de forma a atingirem patamares de produtividade e performance aos níveis internacionais. A envolvente externa às empresas caboverdeanas tem sido alvo de alterações profundas com a globalização dos mercados e o novo paradigma de economia baseada no conhecimento. Para que as empresas mantenham posições competitivas são muitos os desafios que terão que superar. Inexoravelmente, terão que reorganizar e redefinir os seus processos de negócio e suas estratégias de forma coerente. Os SI/TI constituem o factor potencial de reorganização e modernização, a alavanca de diferenciação competitiva e da concretização de negócios e resultados adicionais. O objectivo deste trabalho é o desenvolvimento e a validação de uma metodologia de enquadramento, análise e avaliação de investimentos em SI/TI. O procedimento proposto é fundamentado pela literatura e nas práticas das empresas cabo-verdianas e visa apoiar as empresas a atingirem estágios de performance e produtividade elevados, decorrentes da utilização optimizada dos recursos oferecidos pelos SI/TI. Porque elevadas somas de recursos financeiros são investidos em Sistemas e Tecnologias de Informação e nem todos os benefícios associados são quantificáveis e dado que os riscos associados são elevados, propõe-se com este trabalho um procedimento metodológico de apoio às empresas. Esta metodologia simplificada de análise de investimentos em Sistemas e Tecnologias da Informação propõe uma abordagem científica, sólida e objectiva de avaliação de investimentos em SI/TI, visando propiciar incremento do valor acrescentado dos produtos e/ou serviços das empresas. Os resultados obtidos a partir das análises quantitativas e qualitativas elaboradas permitem retratar a prática das empresas caboverdeanas no domínio de análise e avaliação de investimentos em SI/TI e gerar inferências importantes sobre o comportamento dos responsáveis empresariais e de SI/TI. The increase in competition by the Capeverdean companies is taking place mainly because of the historic moment the country is going through. The recent nomination of Cape Verde as a medium development country, the adhesion to the WCO (World Commerce Organization) and the special partnership with the European Union are relevant reasons for the national companies and others that operate in the Capeverdean market to define efficiently their organizational processes in order to reach levels of productivity and performance comparable to the international ones. The external component of the Capeverdean companies has been undergoing deep changes with market globalization and with the new economic paradigma based on kowledge. In order to maintain their competitive position there are many challenges to overcome. Surely and steadily, they will have to reorganize and redefine their business processes and strategies in a coherent way. The IS/IT (information systems / information technologies) constitute the potential factor of reorganization and modernization, the boost-lever that will produce competitive diferentiation and concretization of businesses and additional results. The main goal of this work is development and validation of a methology of insertion, analysis and evaluation of investments in the IS/IT. The proposed procedure is fundamented by the literature and practice of the Capeverdian companies, and aims at supporting these companies so that they can reach high stages of performance and productivity due to the correct use of the resources offered by the IS/IT. As high amounts of financial resources are invested in Information Systems and Tehnologies, and because of the fact that not all associated benefits may be quantified, and since the associated risks are high, with this work we propose a methodological procedure to support these companies. This simplified analysis methodology in Information and Technologies Systems proposes a sound and objective scientific approach to evaluate investments in IS/IT aiming at providing an increase of the added value of the products and/or services supplied by these companies. The incoming results from the quantitative and qualitative analyses made will allow portraying the practice of the capeverdean companies in the domain of analysis and evaluation of investments in IS/IT and generating important inferences on the behaviour of the executives and IS/IT.

The view of teachers on bullying and implications for nursing

Objective: To understand school bullying from the perspective of teachers and reflect about the possible actions of the health area when coping with it. The guidelines of the School Health Program of the Ministries of Health and Education were used to reach that purpose. Method: A qualitative study carried out with teachers of a public school in Minas Gerais. Focus groups were used to collect data and the empirical material was decoded from thematic analysis of content, resulting in an analytical category: conceptions and experiences of teachers on bullying. Results: Specific perceptions about the phenomenon and the use of ineffective intervention resources were identified. In the interpretive plan were problematized the health and nursing contributions with resizing the interventions and the continuing training process of teachers. Conclusion: The results point to the construction of intersectoral practices for coping with bullying.


Evaporation from a shallow water table: Diurnal dynamics of measured and simulated water and heat regime at the vicinity of a drying sand surface

Accurate estimates of water losses by evaporation from shallow water tables are important for hydrological, agricultural, and climatic purposes. An experiment was conducted in a weighing lysimeter to characterize the diurnal dynamics of evaporation under natural conditions. Sampling revealed a completely dry surface sand layer after 5 days of evaporation. Its thickness was <1 cm early in the morning, increasing to reach 4?5 cm in the evening. This evidence points out fundamental limitations of the approaches that assume hydraulic connectivity from the water table up to the surface, as well as those that suppose monotonic drying when unsteady conditions prevail. The computed vapor phase diffusion rates from the apparent drying front based on Fick's law failed to reproduce the measured cumulative evaporation during the sampling day. We propose that two processes rule natural evaporation resulting from daily fluctuations of climatic variables: (i) evaporation of water, stored during nighttime due to redistribution and vapor condensation, directly into the atmosphere from the soil surface during the early morning hours, that could be simulated using a mass transfer approach and (ii) subsurface evaporation limited by Fickian diffusion, afterward. For the conditions prevailing during the sampling day, the amount of water stored at the vicinity of the soil surface was 0.3 mm and was depleted before 11:00. Combining evaporation from the surface before 11:00 and subsurface evaporation limited by Fickian diffusion after that time, the agreement between the estimated and measured cumulative evaporation was significantly improved.

O Processo de Raciocínio na Teoria dos Constrangimentos Aplicado numa Instituição de Ensino Superior

A Teoria dos Constrangimentos (TOC) ou das Restrições tem-se mostrado uma valiosa ferramenta de gestão, auxiliando na identificação dos constrangimentos que limitem a capacidade das empresas na prossecução da sua meta. Assim, para as restrições não físicas, a TOC desenvolveu o Processo de Raciocínio que é composto por ferramentas de análise lógica que dão subsídios para o diagnóstico de problemas bem como a formulação de soluções e planos de acção para implementá-las. Neste contexto, este trabalho se propõe a determinar a adequação do Processo de Raciocínio da Teoria dos Constrangimentos numa Instituição de Ensino Superior (IES) como forma de diagnosticar os problemas e propor soluções capazes de permitir a empresa uma melhoria contínua do seu desempenho. Serão avaliadas as ferramentas que compõem o Processo de Raciocínio, que são: Árvore de Realidade Actual, Diagrama de Dispersão de nuvens, Árvore de Realidade Futura, Árvore de Pré-Requisitos e Árvore de Transição. O trabalho inicia-se com uma pesquisa bibliográfica seguida de uma pesquisa de campo e finalizando com uma aplicação do PR numa IES localizada na ilha de São Vicente. A colecta de informações para a análise processou-se mediante a aplicação de um questionário fechado aos discentes e funcionários, questionário aberto aos docentes e entrevista estruturada aos dirigentes, elaborados em coerência com os objectivos que este estudo pretende atingir. Os resultados da aplicação do método aqui apresentado permitiram chegar as conclusões apontadas no capítulo final deste trabalho The Theory of Constraints (TOC) or Restriction Theory has proved to be a valuable management tool, assisting in the identification of constraints that restrict the ability of companies in the pursuit of its goals. Therefore, for the nonphysical constraints, TOC developed the Thinking Process (TP) that consists of logical analysis tools that provide a basis for diagnosing problems and formulating solutions and action plans to implement them. This study aims, thus, to determine the suitability of the use of the Thinking Process of the Theory of Constraints in a Higher Education Institution (HEI) as a way to diagnose problems and propose solutions that enable the firm to continually improve their performance. We will evaluate the tools that make up the TP, which are: Current Reality Tree, Evaporating Cloud Diagram, Future Reality Tree, Prerequisites Tree and Transition Tree. The work starts with a literature review, followed by a field search, and finishes with an application of the reasoning process in a higher education institution, located in São Vicente. The collection of the data for the analysis was processed through the application of a closed questionnaire to students and staff, opened questionnaire to teachers and interviews to management, drafted in line with the objectives that this study aims to reach. The results of the application of the method presented here, allowed us to reach the conclusions drawn in the final chapter of this work.

Aplicação da Teoria dos Constrangimentos ao Sector de Transporte Público Colectivo – O Caso Da Transcor-Sv, S.A. –

Com a necessidade de adaptação às crescentes mudanças no mundo dos negócios, ao longo dos últimos anos a contabilidade de gestão tem sido criticada, pois os métodos de custeio tradicionalmente utilizados, não estão acompanhando estas mudanças, incapacitando a utilização destes como instrumentos de gestão eficazes. Na busca de ferramentas de gestão para auxiliar na tomada de decisão, foi desenvolvida a Teoria dos Constrangimentos (TOC) ou das Restrições, uma ferramenta de gestão cuja premissa é a identificação de constrangimentos que limitem a capacidade da empresa no alcance da sua meta. Muito se tem escrito sobre a aplicação desta teoria em empresas industriais, uma vez que, nessas organizações a existência de constrangimentos está mais presente. Tendo como objectivo verificar a viabilidade de aplicação desta teoria na actividade de prestação de serviços, o presente trabalho refere-se ao estudo de caso numa empresa de prestação de serviço de transporte público colectivo de passageiros TRANSCOR-SV,S.A., localizada na ilha de São Vicente. Para tal, identificámos factores considerados constrangimentos nos sistemas de transporte colectivo, através da aplicação de um questionário. Com estes factores em mãos, aplicámos a metodologia baseada no Processo de Raciocínio (PR) da OC. With the need of adaption to the growing changes happening in the business world, throughout the last few years, management accounting has been much criticized for the methods of costing used are not following such changes, turning the use of these meth-ods powerless to help provide an effective management in companies. In the search for creating useful tools to help guarantee effectiveness in decision making in companies, the Constraint Theory, or Restriction Theory, was created as a management tool in which the fundamental objective is to identify constraints that limit the capacity of a company to reach its goals successfully. Much has been written about the application of this theory in corporate industries, once in such business the existence of constraints is very present. With the aim of verifying the viability of its use in service rendered in collective public transport, this work is characterized by the case study of one such company in São Vicente. Initially, some factors that can be seen as constraints were identified in the public transport service, through the use of a questionnaire. With the results, follows the employ of the Thinking Process methodology in the analysis based in the Theory of Constraint.

Urinary incontinence nursing diagnoses in patients with stroke

Abstract OBJECTIVE Identifying the prevalence of Stress urinary incontinence (SUI), Urge urinary incontinence (UUI), Functional urinary incontinence (FUI), Overflow urinary incontinence (OUI) and Reflex urinary incontinence (RUI) nursing diagnoses and their defining characteristics in stroke patients. METHOD A cross-sectional study with 156 patients treated in a neurological clinic. Data were collected through interviews and forwarded to nurses for diagnostic inference. RESULTS 92.3% of the patients had at least one of the studied diagnoses; OUI showed the highest prevalence (72.4%), followed by FUI (53.2%), RUI (50.0%), UUI (41.0%) and SUI (37.8%). Overdistended bladder and reports of inability to reach the toilet in time to avoid urine loss were the most prevalent defining characteristics. A statistically significant association of the defining characteristics with the studied diagnosis was verified. CONCLUSION The five incontinence diagnoses were identified in the evaluated patients, with different prevalence.

Increased connexin43 expression in human sphenous veins in culture is associated with intimal hyperplasia

Résumé Objectif : L'hyperplasie intimale est un processus de remodelage vasculaire qui apparaît après une lésion vasculaire. Les mécanismes impliqués dans l'hyperplasie intimale sont la prolifération, la dédifférentiation et la migration des cellules musculaires lisses depuis la média vers l'espace sous-intimal. Nous avons émis l'hypothèse que les jonctions communicantes de type gap, qui coordonnent certains processus physiologiques tels que la croissance et la différentiation cellulaire, pouvaient participer au développement de l'hyperplasie intimale. Méthodes : Des segments de veines saphènes humaines prélevées chirurgicalement lors de pontages, ont été ouverts longitudinalement avec la surface luminale placée vers le haut et maintenus en culture pendant 14 jours. Des fragments veineux ont été préparés pour une évaluation histologique, pour des mesures de l'épaisseur de la néointima, et pour des analyses immunocytochimiques de l'ARN messager ainsi que des protéines. Résultats : Parmi les 4 connexines (Cxs 37, 40, 43 et 45) qui forment les jonctions communicantes dans les veines, nous avons focalisé notre étude sur l'expression des Cxs 43 et 40; nous avons démontré que la Cx43 est exprimée dans les cellules musculaires lisses et les cellules endothéliales alors que la Cx40 est uniquement présente dans l'endothélium. Après 14 jours en culture, des analyses histomorphométriques ont montré une augmentation significative de l'épaisseur de l'intima démontrant la présence d'hyperplasie intimale. Une analyse temporelle a révélé une augmentation progressive de la Cx43 jusqu'à une augmentation maximale de six à huit fois au niveau de l'ARN messager et des protéines après 14 jours en culture. Au contraire, l'expression de la Cx40 n'était pas modifiée. Des analyses par immunofluorescence ont montré également une augmentation de la Cx43 dans les membranes des cellules musculaires lisses de la média. Le développement de l'hyperplasie intimale in vitro est diminué en présence de fluvastatin et cette diminution est associée à une réduction de l'expression de la Cx43. Conclusions : Ces données démontrent que la Cx43 est augmentée in vitro pendant le processus d'hyperplasie intimale et que la fluvastatin prévient cette induction. Ces résultats suggèrent un rôle crucial joué par la communication intercellulaire impliquant la Cx43 dans la veine humaine durant le développement de l'hyperplasie intimale. Abstract Objective: Intimal hyperplasia is a vascular remodelling process that occurs after a vascular injury. The mechanisms involved in intimal hyperplasia are proliferation, dedifferentiation, and migration of medial smooth muscle cells towards the subintimal space. We postulated that gap junctions, which coordinate physiologic processes such as cell growth and differentiation, might participate in the development of intimal hyperplasia. connexin43 (Cx43) expression levels may be altered in intimal hyperplasia, and we therefore evaluated the regulated expression of Cx43 in human saphenous veins in culture in the presence or not of fluvastatin, an inhibitor of 3-hydroxy-3-methylglutaryl-coenzyme A reductase activity. Methods: Segments of harvested human saphenous veins, obtained at the time of bypass graft, were opened longitudinally with the luminal surface uppermost and maintained in culture for 14 days. Vein fragments were then processed for histologic examination, neointimal thickness measurements, immunocytochemistry, RNA, and proteins analysis. Results: Of the four connexins (Cx37, 40, 43, and 45), we focused on Cx43 and Cx40, which we found by real-time polymerase chain reaction to be expressed in the saphenous vein because they are the predominant connexins expressed by smooth muscle cells and endothelial cells. Afrer 14 days of culture, histomorphometric analysis showed a significant increase in the intimal thickness as observed during the process of intimal hyperplasia. Atime-course analysis revealed a progressive upregulation of Cx43 to reach a maximal increase of sixfold to eightfold at both transcript and protein levels after 14 days in culture. In contrast, the expression of Cx40, abundantly expressed in the endothelial cells, was not altered. Immunofluorescence showed a large increase in Cx43 within smooth muscle cell membranes of the media layer. The development of intimal hyperplasia in vitro was decreased in presence of fluvastatin and was associated with reduced Cx43 expression. Conclusions: These data show that Cx43 is increased in vitro during the process of intimal hyperplasia and that fluvastatin could prevent this induction, supporting a critical role for Cx43-mediated gap-junctional communication in the human vein during the development of intimal hyperplasia. (J Vasc Surg 2005;41:1043-52.)

Quasi-integration in less-than-truckload trucking

This work studies the organization of less-than-truckload trucking from a contractual point of view. We show that the huge number of owner-operators working in the industry hides a much less fragmented reality. Most of those owner-operators are quasi-integrated in higher organizational structures. This hybrid form is generally more efficient than vertical integration because, in the Spanish institutional environment, it lessens serious moral hazard problems, related mainly to the use of the vehicles, and makes it possible to reach economies of scale and density. Empirical evidence suggests that what leads organizations to vertically integrate is not the presence of such economies but hold-up problems, related to the existence of specific assets. Finally, an international comparison hints that institutional constraints are able to explain differences in the evolution of vertical integration across countries.

On equilibria in duopolies with finite strategy spaces

We will call a game a reachable (pure strategy) equilibria game if startingfrom any strategy by any player, by a sequence of best-response moves weare able to reach a (pure strategy) equilibrium. We give a characterizationof all finite strategy space duopolies with reachable equilibria. Wedescribe some applications of the sufficient conditions of the characterization.

O contributo da contabilidade numa gestão transparente das OSFL - Caso: ADECO

Na actualidade, tem-se cada vez mais a consciência da necessidade e da importância de ter uma informação financeira credível e em tempo oportuno. A informação financeira passou a ser a base para avaliação do desempenho dos gestores, assim como para análise da situação económico-financeira das Organizações. A informação só é útil para tomada de decisão se tiverem as seguintes características qualitativas: Compreensibilidade, Relevância, Fiabilidade e Comparabilidade. No ambiente concorrencial em que as Organizações estão inseridas, a Contabilidade tem um papel fulcral como instrumento de tomada de decisão. As Organizações que têm como objectivos acções sociais, actuam nas áreas como: culturais e recreativas, solidariedade social, promoção do desenvolvimento comunitário, educacionais, de protecção ao ambiente, Saúde e da promoção da higiene, entre outros. Como essas Organizações não têm com objectivo o lucro, é necessário ter uma boa gestão e para que isso seja possível, é preciso ter-se instrumentos capazes para que isso seja possível e é neste âmbito que a Contabilidade entra como um auxílio para a gestão, como ferramenta capaz de mensurar e controlar processos, resultados e impactos nos projectos executados, a fim de que seus objectivos sociais sejam alcançados de uma forma consistente com o planeado. A sustentabilidade, a necessidade de demonstração e de aplicação dos recursos obtidos é um forte desafio que as Organizações do terceiro sector têm de ultrapassar e, neste âmbito, a Contabilidade pode constituir um meio importante para atingir esses objectivos, através da demonstração dos resultados alcançados. Nesta base, o contributo da Contabilidade na gestão das OSFL tem-se acentuado cada vez mais, demonstrando transparência na apresentação das suas contas, facilitando na captação de recursos e na fidelização dos seus parceiros e financiadores. Nowadays it has become increasingly aware of the need and importance of having credible and timely financial information. The financial information started to be the base for evaluation of the managers acting, as well as for analysis of the economicfinancial situation of the company. The information is only useful for socket of decision if they have the following qualitative characteristics: Comprehensive, Relevance, Reliable and Comparability. In the atmosphere concurrencies in that the Organizations are inserted the accounting has a crucial paper as instrument of socket of decision in the Organizations. The Organizations that have as purpose social action as for instance: cultural and recreational, social solidarity, promotion of the development community, education, of protection to the atmosphere, health and of the promotion of the hygiene, among others. As those Organizations don't have with objective the profit, it is necessary to have a good administration and for that to be possible, it is necessary to have capable instruments for that to be possible and it is in this extent that the accounting enters as an aid for the administration, as tool capable to measure and to control processes, results and impacts in the executed projects, so that their social objectives are reached in a solid way with the planed. Sustainability, the demonstration of the achieved results and the application of resources collected are strong challenges that the Organizations of the third sector have to overcome. To that extent, Accounting can contribute as an important way to reach those objectives through the demonstration of resources collected. In this base, the contribution of the Accounting has been accentuating more and more in the administration of the nonprofit organizations, demonstrating transparency in the presentation of their finance statements, facilitating the fundraising of Organizations and loyal partners and funders.

Aspects thérapeutiques de la vitamine D: quels taux cibler avec quels traitements [Therapeutic goal of vitamin D: optimal serum level and dose requirements].

Therapeutic goal of vitamin D: optimal serum level and dose requirements Results of randomized controlled trials and meta-analyses investigating the effect of vitamin D supplementation on falls and fractures are inconsistent. The optimal serum level 25(OH) vitamin D for musculoskeletal and global health is > or = 30 ng/ml (75 nmol/l) for some experts and 20 ng/ml (50 nmol/l) for some others. A daily dose of vitamin D is better than high intermittent doses to reach this goal. High dose once-yearly vitamin D therapy may increase the incidence of fractures and falls. High serum level of vitamin D is probably harmful for the musculoskeletal system and health at large. The optimal benefits for musculoskeletal health are obtained with an 800 UI daily dose and a serum level of near 30 ng/ml (75 nmol/l).

Insects of forensic importance from Rio Grande do Sul state in southern Brazil

The experiment was conducted throughout the year 2005, at the Universidade Federal de Pelotas campus. The objectives of the study were to analyze the decomposition of rabbit (Oryctolagus cunniculus L.) with mean weight 2.67 Kg carcass and describe the interaction of insects acting on it, as well as the insect's potential use in legal medicine. We collected 5.239 insect specimens; 1.827 of them were obtained from larvae collected from carcasses and reared. The specimens were identified and 20 species were of forensic importance. The species Lucilia eximia (Wiedemann, 1819) and Chrysomya albiceps (Wiedemann, 1819) (Diptera, Calliphoridae) were better indicators of post-mortem interval (PMI) because they occurred in all seasons and were the first to reach the carcass. Hemilucilia semidiaphana (Rondani, 1850), H. segmentaria (Fabricius, 1805) (Diptera, Calliphoridae), Muscina stabulans (Fallén, 1817) and Synthesiomyia nudiseta (Wulp, 1883) (Diptera, Muscidae) can disclose death time because they occur only in certain months of the year. Oxyletrum discicolle (Brullé, 1840) (Coleoptera, Silphidae) and Dermestes maculates De Geer, 1774 (Coleoptera, Desmestidae) were found in advanced stages of decomposition.