142 resultados para Flexible tubular structures
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Introduction The flexible derotator is one of the therapeutic resources used to combat primary and secondary abnormalities in walking cerebral palsy children. It was developed to reduce abnormal femoral and tibial torsions and lessen the latter's negative functional impact. Objective To determine the effect of wearing a flexible derotator on anatomic and functional parameters in walking cerebral palsy children. Methods We performed a retrospective study of walking cerebral palsy children by gathering data on bone-related parameters (femoral and tibial torsion) and functional parameters (distance and speed gait, and the energy expenditure index (EEI)). Fifteen walking cerebral palsy children were treated with the flexible derotator for one year and 15 untreated walking cerebral palsy children were included as controls. The two groups were compared in terms of the various parameters' change over time between the initial examination (the last examination prior to the start of the study or prior to use of the flexible derotator) and the final examination (after one year of follow-up). Results Right femoral anteversion and right and left external tibial torsion improved. There was a significant increase in distance and speed gait and a decrease in the EEI in walking cerebral palsy children. Conclusion Our retrospective study revealed a significant improvement in functional parameters in children with cerebral palsy, as a result of wearing the flexible derotator for at least 6 hours a day for a year. Bone parameters only improved slightly. Use of the flexible derotator could improve these children's quality of life.
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Recent studies have pointed out a similarity between tectonics and slope tectonic-induced structures. Numerous studies have demonstrated that structures and fabrics previously interpreted as of purely geodynamical origin are instead the result of large slope deformation, and this led in the past to erroneous interpretations. Nevertheless, their limit seems not clearly defined, but it is somehow transitional. Some studies point out continuity between failures developing at surface with upper crust movements. In this contribution, the main studies which examine the link between rock structures and slope movements are reviewed. The aspects regarding model and scale of observation are discussed together with the role of pre-existing weaknesses in the rock mass. As slope failures can develop through progressive failure, structures and their changes in time and space can be recognized. Furthermore, recognition of the origin of these structures can help in avoiding misinterpretations of regional geology. This also suggests the importance of integrating different slope movement classifications based on distribution and pattern of deformation and the application of structural geology techniques. A structural geology approach in the landslide community is a tool that can greatly support the hazard quantification and related risks, because most of the physical parameters, which are used for landslide modeling, are derived from geotechnical tests or the emerging geophysical approaches.
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Networks are considered increasingly important for policy-making. The literature on new modes of governance in Europe suggests that their horizontal coordination capacity and flexible and informal structures are particularly suitable for governing the multilevel architecture of the European polity. However, empirical evidence about the effects of networks on policy-making and public policies is still quite limited. This article uses the case of the European network of energy regulators to explore the determinants of the position of network members and, in turn, the domestic adoption of soft rules developed within this network. The empirical analysis, based on multivariate statistics and semi-directive interviews, supports the expectation that institutional complementarities increase actors' centrality in networks, while arguments based on organisational resources and age are disproved. Furthermore, results show that the overall level of adoption is considerable and that centrality might have a small positive effect on domestic adoption.
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OBJECTIVE: The goal of this study was to investigate whether angiotensin II receptor blockers (ARBs) induce a comparable blockade of AT1 receptors in the vasculature and in the kidney when the renin-angiotensin system is activated by a thiazide diuretic. METHOD: Thirty individuals participated in this randomized, controlled, single-blind study. The blood pressure and renal hemodynamic and tubular responses to a 1-h infusion of exogenous angiotensin II (Ang II 3 ng/kg per min) were investigated before and 24 h after a 7-day administration of either irbesartan 300 mg alone or in association with 12.5 or 25 mg hydrochlorothiazide (HCTZ). Irbesartan 300/25 mg was also compared with losartan 100 mg, valsartan 160 mg, and olmesartan 20 mg all in association with 25 mg HCTZ. Each participant received two treatments with a 1-week washout period between treatments. RESULTS: The blood pressure response to Ang II was blocked by more than 90% with irbesartan alone or in association with HCTZ and with olmesartan/HCTZ and by nearly 60% with valsartan/HCTZ and losartan/HCTZ (P < 0.05). In the kidney, Ang II reduced renal plasma flow by 36% at baseline (P < 0.001). Irbesartan +/- HCTZ and olmesartan/HCTZ blocked the renal hemodynamic response to Ang II nearly completely, whereas valsartan/HCTZ and losartan/HCTZ only blunted this effect by 34 and 45%, respectively. At the tubular level, Ang II significantly reduced urinary volume (-84%) and urinary sodium excretion (-65%) (P < 0.01). These tubular effects of Ang II were only partially blunted by the administration of ARBs. CONCLUSION: These data demonstrate that ARBs prescribed at their recommended doses do not block renal tubular AT1 receptors as effectively as vascular receptors do. This observation may account for the need of higher doses of ARB for renal protection. Moreover, our results confirm that there are significant differences between ARBs in their capacity to induce a sustained vascular and tubular blockade of Ang II receptors.
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Fanconi anemia (FA) is a genetically heterogeneous chromosome instability syndrome associated with congenital abnormalities, bone marrow failure, and cancer predisposition. Eight FA proteins form a nuclear core complex, which promotes tolerance of DNA lesions in S phase, but the underlying mechanisms are still elusive. We reported recently that the FA core complex protein FANCM can translocate Holliday junctions. Here we show that FANCM promotes reversal of model replication forks via concerted displacement and annealing of the nascent and parental DNA strands. Fork reversal by FANCM also occurs when the lagging strand template is partially single-stranded and bound by RPA. The combined fork reversal and branch migration activities of FANCM lead to extensive regression of model replication forks. These observations provide evidence that FANCM can remodel replication fork structures and suggest a mechanism by which FANCM could promote DNA damage tolerance in S phase
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Glycosyl-inositolphospholipid (GPL) anchoring structures are incorporated into GPL-anchored proteins immediately posttranslationally in the rough endoplasmic reticulum, but the biochemical and cellular constituents involved in this "glypiation" process are unknown. To establish whether glypiation could be achieved in vitro, mRNAs generated by transcription of cDNAs encoding two GPL-anchored proteins, murine Thy-1 antigen and human decay-accelerating factor (DAF), and a conventionally anchored control protein, polymeric-immunoglobulin receptor (IgR), were translated in a rabbit reticulocyte lysate. Upon addition of dog pancreatic rough microsomes, nascent polypeptides generated from the three mRNAs translocated into vesicles. Dispersal of the vesicles with Triton X-114 detergent and incubation of the hydrophobic phase with phosphatidylinositol-specific phospholipases C and D, enzymes specific for GPL-anchor structures, released Thy-1 and DAF but not IgR protein into the aqueous phase. The selective incorporation of phospholipase-sensitive anchoring moieties into Thy-1 and DAF but not IgR translation products during in vitro translocation indicates that rough microsomes are able to support and regulate glypiation.
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RESUME Fractures du fémur chez les enfants d'âge préscolaire. Expérience avec l'enclouage centromédullaire élastique stable chez 72 enfants Introduction L'immobilisation plâtrée est le traitement le plus fréquemment utilisé pour traiter les fractures du fémur chez les enfants d'âge préscolaire de moins de 6 ans. L'enclouage centromédullaire élastique stable (ECMES), qui a remplacé les immobilisations plâtrées chez les enfants d'âge scolaire, est une alternative qui n'a jamais été étudiée spécifiquement dans la tranche d'âge préscolaire. Matériel et Méthode Nous avons réalisé une étude rétrospective de tous les cas de fractures du fémur chez l'enfant de moins de 6 ans traitées par ECMES dans le service de chirurgie pédiatrique du Centre Hospitalier Universitaire Vaudois et de l'Hôpital de l'Enfance de Lausanne sur une période de 15 ans. Résultats Parmi les 210 fractures du fémur traitées par ECMES entre le 1.1.1988 et le 31.12.2003, 74 fractures du fémur ont été identifiées chez 73 enfants âgés de 1.5 à 5.9 ans. Ces fractures étaient sous-trochantériennes (n=5), diaphysaires (n=64, dont 5 ouvertes), ou métaphysaires discales (n=4). Le type de fracture était transverse (n=35, dont 2 ouvertes), oblique (n=28, dont 3 ouvertes) au spiroïde (n=11). Quatre fractures étaient comminutives. Le temps opératoire moyen était de 56,9 minutes (limites entre 20 et 155 min.) pour les enfants ne présentant pas d'autre pathologie chirurgicale. Le séjour hospitalier moyen était de 9.1 jours (limites entre 1 et 46 jours) pour tous les enfants n'ayant pas de pathologie associée. Chez les enfants sans lésion ou pathologie associée, la première mise en charge s'est effectuée en moyenne au 14,1 ème jour post-opératoire (limites entre 1 et 42ème jour) alors que la première mobilisation a eu lieu en moyenne dès le 2,7ème jour post-opératoire (limites entre le 1 et le 14ème jour). 64 enfants ont été suivis à long terme avec un recul moyen de. 36,8 mois (limites entre 4 et 124 mois). Nous avons relevés 6 enfants avec une inégalité de longueur de plus d'un centimètre, alors que nous n'avons jamais constaté de défaut de rotation. Durant le 11 premières années de l'étude, 9 enfants ont dû être réopérés pour raccourcissement secondaire de broches extériorisées ou douloureuses sous la peau. Aucun problème de broche n'a été observé après introduction d'une nouvelle pince à couper. 2 réductions de fracture se sont faites à foyer ouvert. Une infection localisée transitoire du point de ponction d'une broche a été notée, sans ostéite associée. Discussion L' ECMES chez le petit enfant est techniquement réalisable sans véritable limite inférieure d'âge. Il favorise la mobilisation et la charge précoces. Les complications sont avant tout en rapport avec la technique et peuvent être évitées. Les résultats sont au moins aussi bons et meilleurs sur certains points que ceux publiés en utilisant les immobilisations. En outre ce traitement évite une longue hospitalisation. Conclusions L'ECMES peut être appliqué aux enfants de moins de 6 ans avec les mêmes bénéfices que ceux observés pour les plus grands, sans en augmenter la morbidité. La limite inférieure d'âge reste à déterminer. Un suivi à long terme s'impose pour vérifier l'absence d'inégalité de longueur des membres inférieurs.
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High-resolution structural information on optimally preserved bacterial cells can be obtained with cryo-electron microscopy of vitreous sections. With the help of this technique, the existence of a periplasmic space between the plasma membrane and the thick peptidoglycan layer of the gram-positive bacteria Bacillus subtilis and Staphylococcus aureus was recently shown. This raises questions about the mode of polymerization of peptidoglycan. In the present study, we report the structure of the cell envelope of three gram-positive bacteria (B. subtilis, Streptococcus gordonii, and Enterococcus gallinarum). In the three cases, a previously undescribed granular layer adjacent to the plasma membrane is found in the periplasmic space. In order to better understand how nascent peptidoglycan is incorporated into the mature peptidoglycan, we investigated cellular regions known to represent the sites of cell wall production. Each of these sites possesses a specific structure. We propose a hypothetic model of peptidoglycan polymerization that accommodates these differences: peptidoglycan precursors could be exported from the cytoplasm to the periplasmic space, where they could diffuse until they would interact with the interface between the granular layer and the thick peptidoglycan layer. They could then polymerize with mature peptidoglycan. We report cytoplasmic structures at the E. gallinarum septum that could be interpreted as cytoskeletal elements driving cell division (FtsZ ring). Although immunoelectron microscopy and fluorescence microscopy studies have demonstrated the septal and cytoplasmic localization of FtsZ, direct visualization of in situ FtsZ filaments has not been obtained in any electron microscopy study of fixed and dehydrated bacteria.
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In this article, we explore the contractual design of toll road concession contracts. We highlight the fact that contracting parties try to sign not only complete rigid contracts in order to avoid renegotiations but also flexible contracts in order to adapt contractual framework to contingencies and to create incentives for cooperative behavior. This gives rise to multiple toll adjustment provisions and to a tradeoff between rigid and flexible contracts. Such a tradeoff is formalized using an incomplete contract framework - including ex post maladaptation and renegotiation costs - and propositions are tested using an original database of 71 concession contracts. Our results suggest an important role for economic efficiency concerns, as well as politics, in designing such public-private contracts. Codes JEL : D23, H11, H54, L14, L9.
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The present study compares the higher-level dimensions and the hierarchical structures of the fifth edition of the 16 PF with those of the NEO PI-R. Both inventories measure personality according to five higher-level dimensions. These inventories were however constructed according to different methods (bottom-up vs. top-down). 386 participants filled out both questionnaires. Correlations, regressions and canonical correlations made it possible to compare the inventories. As expected they roughly measure the same aspects of personality. There is a coherent association among four of the five dimensions measured in the tests. However Agreeableness, the remaining dimension in the NEO PI-R, is not represented in the 16 PF 5. Our analyses confirmed the hierarchical structures of both instruments, but this confirmation was more complete in the case of the NEO PI-R. Indeed, a parallel analysis indicated that a four-factor solution should be considered in the case of the 16 PF 5. On the other hand, the NEO PI-R's five-factor solution was confirmed. The top-down construction of this instrument seems to make for a more legible structure. Of the two five-dimension constructs, the NEO PI-R thus seems the more reliable. This confirms the relevance of the Five Factor Model of personality.
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OBJECTIVE: The occurrence of the 2003 G8 summit in Evian and the threat of major civil riots or even terrorist attacks in the Swiss neighbourhood forced us to imagine a new system of rescue and medical care in case of numerous victims. Previous occurrences of the G8 in Europe or America have demonstrated the need of flexible and mobile structures, able to respond quickly to crowd movements, unlike the usual static structure of rescue systems designed for major accidents. METHODS: We developed a new concept of Mobile Medical Squadrons (MMS) consisting of several vehicles and medical care and rescue human resources. In our concept, each MMS consisted of 3 emergency doctors, 5 paramedics and 9 first-aid workers. They were designed to handle 15 patients, with a large autonomy in terms of rescue, medical care, evacuation and medical authority. The equipment included medical, resuscitation, simple decontamination, evacuation and communication materials. RESULTS: The MMS were dispatched four times during the G8 summit following civil riots. They took care of 12 injured patients. CONCLUSION: The concept of MMS as a reinforcement of the existing rescue and health care resources appears as a new flexible, a modular and useful concept for the medical management of collective prehospital emergency situations. Its use is suggested instead of the traditional static concept of rescue systems designed for major accidents.
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Résumé Objectifs : Le but de ce travail est, dans un premier temps, de mettre en évidence les mécanismes qui gouvernent les rivalités d'usage concernant la ressource paysage, afin, dans un deuxième temps, de comprendre comment se résolvent ces différends. Il part du postulat central que l'existence de rivalités d'usage non apaisées nuit à la durabilité de la ressource. Trois types d'acteurs gravitant autour de la ressource paysage doivent être distingués -Les observateurs du paysage sont ceux qui utilisent directement les services fournis par la ressource (p. ex. les touristes « écologiques », les randonneurs, les amoureux de la nature ; dans les conflits, ils peuvent être représentés par les organisations de protection du paysage) ; -Les fournisseurs du paysage servent d'intermédiaires entre le paysage et les observa¬teurs ; ils utilisent le paysage pour attirer des clients ; ils monnayent l'accès au paysage (billet de transport, hôtels, restaurant panoramique) ; ils vendent des représentations du paysage ; -Les utilisateurs des ressources « primaires » (sol, eau, forêt...) ne se préoccupent pas de paysage : ils entretiennent une configuration particulière de ressources primaires qui fait naître chez l'observateur le sentiment qu'il contemple un paysage. Ces catégories analytiques ne sont pas hermétiques, car un même acteur peut se trouver dans plusieurs catégories à la fois. Cadre d'analyse : Sur la base de la typologie des acteurs présentée, il est possible de mettre en évidence six types de rivalités théoriques, chacune opposant entre eux des observateurs, fournisseurs et utilisateurs de ressources primaires. Dans une situation de rivalité, les différents acteurs mobilisent les droits qu'ils ont à disposition pour défendre leurs intérêts. Le cadre d'analyse des régimes institutionnels de ressources naturelles (RIRN) est utilisé afin de mettre en évi¬dence ces droits. Il permet de faire la différence entre le système régulatif de la ressource, qui fait référence aux phénomènes d'appropriation (à défaut de propriété, car le paysage n'entre pas facilement dans les canons définis par le code civil), et les politiques publiques, qui ré¬glementent ces phénomènes d'appropriation. Le cadre des RIRN a la prétention de tisser un lien entre l'économie institutionnelle des ressources naturelles, préoccupée avant tout par la question des droits sur les ressources, et une approche plus politologique, dont les politi¬ques publiques constituent l'objet d'étude. Résultats : Dans le contexte de trois études de cas (le val Baltschieder, la région d'Aletsch et le parc naturel régional de Chartreuse), les conflits paysagers ont été mis en évidence. Les acteurs en présence ont été identifiés, de même que les droits dont ils disposent pour protéger leurs intérêts. Ce travail a démontré que les rivalités entre observateurs (p. ex. surdensité de visi¬teurs), ainsi que celles entre observateurs et utilisateurs de ressources primaires ne trouvent pas de solution sans l'intervention d'une structure de gestion paysagère particulière. Cette dernière peut prendre différentes formes qui doivent toutefois respecter un certain nombre de critères développés dans le travail. Dans le contexte des études de cas, différents modèles d'organisation susceptibles de jouer ce rôle ont été mis en évidence. De telles organisations collectives constituent une des clés pour une gestion durable de la ressource paysage.