939 resultados para Crack-bridging
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Dendritic cells (DCs) are central player in immunity by bridging the innate and adaptive arms of the immune system (IS). Interferons (IFNs) are one of the most important factors that regulate both innate and adaptive immunity too. Thus, the understanding of how type II and I IFNs modulate the immune-regulatory properties of DCs is a central issue in immunology. In this paper, we will address this point in the light of the most recent literature, also highlighting the controversial data reported in the field. According to the wide literature available, type II as well as type I IFNs appear, at the same time, to collaborate, to induce additive effects or overlapping functions, as well as to counterregulate each one's effects on DC biology and, in general, the immune response. The knowledge of these effects has important therapeutic implications in the treatment of infectious/autoimmune diseases and cancer and indicates strategies for using IFNs as vaccine adjuvants and in DC-based immune therapeutic approaches.
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Notch pathway is crucial for stem/progenitor cell maintenance, growth and differentiation in a variety of tissues. Using a transgenic cell ablation approach, we found in our previous study that cells expressing Notch1 are crucial for prostate early development and re-growth. Here, we further define the role of Notch signaling in regulating prostatic epithelial cell growth and differentiation using biochemical and genetic approaches in ex vivo or in vivo systems. Treatment of developing prostate grown in culture with inhibitors of gamma-secretase/presenilin, which is required for Notch cleavage and activation, caused a robust increase in proliferation of epithelial cells co-expressing cytokeratin 8 and 14, lack of luminal/basal layer segregation and dramatically reduced branching morphogenesis. Using conditional Notch1 gene deletion mouse models, we found that inactivation of Notch1 signaling resulted in profound prostatic alterations, including increased tufting, bridging and enhanced epithelial proliferation. Cells within these lesions co-expressed both luminal and basal cell markers, a feature of prostatic epithelial cells in predifferentiation developmental stages. Microarray analysis revealed that the gene expression in a number of genetic networks was altered following Notch1 gene deletion in prostate. Furthermore, expression of Notch1 and its effector Hey-1 gene in human prostate adenocarcinomas were found significantly down-regulated compared to normal control tissues. Taken together, these data suggest that Notch signaling is critical for normal cell proliferation and differentiation in the prostate, and deregulation of this pathway may facilitate prostatic tumorigenesis.
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Purpose: To evaluate the current management, and adherence to recommendations, of patients on oral anticoagulation (OAC) undergoing coronary stent implantation (PCI-S). Methods: By means of a contact person who had been previously identified in 8 European countries, a questionnaire was electronically forwarded between April and July 2010 to the national institutions where PCI-S is performed. Results: A total of 202 questionnaires (median response rate: 50%, range 33-78%) was received. The prevalence of OAC patients among those undergoing PCI-S is mostly reported 5-10% (97%). The peri-procedural pharmacological management mostly encompasses: preprocedural OAC interruption and bridging with low-molecular-weight heparin (59%), intraprocedural administration of an unfractionated heparin bolus (81%), and use of glycoprotein IIb/IIIa inhibitors on an individual basis (79%). The radial approach is reported as the preferred option (58%), as well as the implantation of bare metal stents (76%). Triple therapy (warfarin, aspirin, clopidogrel) is the most frequently prescribed (80%), generally for 1 month after bare metal stent (77%) and for at least 12 months after drug-eluting stent (60%). Throughout triple therapy, the International Normalized Ratio is mostly targeted to the lower end of the therapeutic range (77%), and gastric protection is routinely prescribed (69%), mostly by giving proton-pump inhibitors (70%). Conclusions: Among the 202 interventional cardiologists from the 8 European countries interviewed, the management of patients on OAC undergoing PCI-S appears variable and only partially adherent to currently available recommendations. (J Interven Cardiol 2012;25:163-169).
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Most educational institutions include nowadays a digital repository as part of their development and positioning strategy. The main goals of a digital repository are preservation and dissemination, which are some how contradictory, especially if the repository follows an open approach, as it is designed, built and managed from an institutional perspective, although it is intended to be used by teachers and learners. This fact may lead to a low level of usage, as final users are not able to integrate the learning object repository into their learning process. In this paper we will discuss how to promote open educational resources by connecting open repositories with open social networks, bridging the gap between resources and final users (teachers and learners).
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BACKGROUND: Recanalization in acute ischemic stroke with large-vessel occlusion is a potent indicator of good clinical outcome. OBJECTIVE: To identify easily available clinical and radiologic variables predicting recanalization at various occlusion sites. METHODS: All consecutive, acute stroke patients from the Acute STroke Registry and Analysis of Lausanne (2003-2011) who had a large-vessel occlusion on computed tomographic angiography (CTA) (< 12 h) were included. Recanalization status was assessed at 24 h (range: 12-48 h) with CTA, magnetic resonance angiography, or ultrasonography. Complete and partial recanalization (corresponding to the modified Treatment in Cerebral Ischemia scale 2-3) were grouped together. Patients were categorized according to occlusion site and treatment modality. RESULTS: Among 439 patients, 51% (224) showed complete or partial recanalization. In multivariate analysis, recanalization of any occlusion site was most strongly associated with endovascular treatment, including bridging therapy (odds ratio [OR] 7.1, 95% confidence interval [CI] 2.2-23.2), and less so with intravenous thrombolysis (OR 1.6, 95% CI 1.0-2.6) and recanalization treatments performed beyond guidelines (OR 2.6, 95% CI 1.2-5.7). Clot location (large vs. intermediate) and tandem pathology (the combination of intracranial occlusion and symptomatic extracranial stenosis) were other variables discriminating between recanalizers and non-recanalizers. For patients with intracranial occlusions, the variables significantly associated with recanalization after 24 h were: baseline National Institutes of Health Stroke Scale (NIHSS) (OR 1.04, 95% CI 1.02-1.1), Alberta Stroke Program Early CT Score (ASPECTS) on initial computed tomography (OR 1.2, 95% CI 1.1-1.3), and an altered level of consciousness (OR 0.2, 95% CI 0.1-0.5). CONCLUSIONS: Acute endovascular treatment is the single most important factor promoting recanalization in acute ischemic stroke. The presence of extracranial vessel stenosis or occlusion decreases recanalization rates. In patients with intracranial occlusions, higher NIHSS score and ASPECTS and normal vigilance facilitate recanalization. Clinical use of these predictors could influence recanalization strategies in individual patients.
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[Table des matières] 1. Concept de la réduction des risques. 2. Stratégie de réduction des risques en France. 3. Usage des drogues en France et principaux dommages associés. 4. Comorbidités psychiatriques chez les usagers de drogues. 5. Risques infectieux chez les usagers de drogues. 6. Evolution de l'incidence du VHC chez les usagers de drogues en France. 7. Pratiques à risque chez les fumeurs de crack. 8. Prévention de l'initiation à l'injection et transitions vers d'autres modes d'administration. 9. Traitements de substitution aux opiacés. 10. Autres traitements de la dépendance. 11. Programmes d'échange de seringues. 12. Centres d'injection supervisés. 13. Parcours de soins des usagers de drogues. 14. Rapport coût-efficacité des dispositifs de réduction des risques. 15. Dispositifs de réduction des risques en France. 16. Accessibilité et acceptabilité des actions de réduction des risques. 17. Réduction des risques adaptée aux femmes. 18. Réduction des risques en milieu pénitentiaire. Synthèse et recommandations. Communications. Usage de drogue et réduction des risques en Europe. Eléments d'histoire sur la politique de réduction des risques en France. Situation de la politique de réduction des risques en France. Approche judiciaire française. Rôle des associations dans la politique de réduction des risques en France. Prévention de la délinquance et réduction des risques et dommages sociaux au Canada. Complications liées à l'auto-injection des traitements de substitution aux opiacés. Contributions des intervenants et associations. Annexes.
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Cocaine use, often not recognized, is a frequent cause of consultation in the emergency room or by primary care physicians. The use of cocaine causes numerous cardiovascular and pulmonary side effects. In this context, the occurrence of a pneumothorax represents a specific complication, often misunderstood by primary care physicians. We describe here three cases of patients who suffered from subcutaneous emphysema and pneumothorax after taking cocaine and emphasize the importance of always keeping in mind the possibility of illicit substance use in such cases, especially among young and healthy patients.
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El estudio desarrollado en la tesis doctoral profundiza en las relaciones existentes entre la microestructura y el comportamiento a rotura y fatiga de tres tipos de Aceros de Herramienta para trabajo en Frío, dos obtenidos por colada y un tercero mediante pulvimetalúrgia. En primer lugar se evaluaron los aspectos microestructurales relacionados con las dos vias de procesamiento empleadas, además del efecto del cambio en la composición química. Asimismo se documentó la influencia del trabajado en caliente sobre la isotropía microestructural. Considerando las caracteristicas microestructurales se evaluó el comportamiento a rotura en tres orientaciones referidas al sentido de la deformación en caliente. Para ello , se empleó la Mecánica de la Fractura Elástica Lineal como marco analítico. Los resultados fueron tratados siguiendo la estadística de Weibull. Para el caso de los aceros colados se implementa un analisis de curva-R para explicar el crecimiento subcrítico de grietas observado experimentalmente. El estudio del comportamiento a fatiga incluyó la determinación del limite a fatiga para todas la orientaciones microestructurales escogidas y el estudio de la cinetica de propagación de fisuras físicamente pequeñas para la orientación con mejor respuesta mecánica.
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The failure mechanism of a voided CFRP 0-90° cross-ply laminate under tensile loads applied in one direction was studied in this Final Degree Project. For this purpose, voided coupons were manufactured for being tested and a FEA was done. In both investigations, voids were placed in 90º and 0º direction, in order to understand the void location influence. On the one hand, the behaviour of the voided laminates was investigated through a FEM in order to preview the stress distribution within the material. On the other hand, voided specimens where manufactured by applying blowing agent in between the inner layers. These specimens were tested by a quasi-static step wise tensile test where data showing its real behaviour was collected. Specimens were X-rayed after each step of the test in order to investigate the failure mechanism of the composite. Data from the test was studied so that relations such as strength of the laminates, crack density per stress, void length per first crack at the void and void area per first crack at the specimen could be characterized
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Here we present a processing route to produce multi-structured ceramic foams based on the combination of particle-stabilized foams with polymeric sponges to produce positive and negative templating structures. Polyester sponges are infiltrated with freshly produced calcium aluminate alumina foams and upon sintering either positive templating structures are produced when wetting the sponges, or negative templating foams with a percolating pore network are obtained when completely filling the sponges. Additionally, by combining different layers of these particle-stabilized foam infiltrated sponges, various different structures can be produced, including sandwich structures, pore size gradients, and ceramic bone-like structures applying to different types of bone. The particle-stabilized foams used were in situ self-hardening calcium aluminate cement enriched alumina foams to obtain crack-free samples with pore interconnections and tailorable pore sizes.
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Comparison of donor-acceptor electronic couplings calculated within two-state and three-state models suggests that the two-state treatment can provide unreliable estimates of Vda because of neglecting the multistate effects. We show that in most cases accurate values of the electronic coupling in a π stack, where donor and acceptor are separated by a bridging unit, can be obtained as Ṽ da = (E2 - E1) μ12 Rda + (2 E3 - E1 - E2) 2 μ13 μ23 Rda2, where E1, E2, and E3 are adiabatic energies of the ground, charge-transfer, and bridge states, respectively, μij is the transition dipole moments between the states i and j, and Rda is the distance between the planes of donor and acceptor. In this expression based on the generalized Mulliken-Hush approach, the first term corresponds to the coupling derived within a two-state model, whereas the second term is the superexchange correction accounting for the bridge effect. The formula is extended to bridges consisting of several subunits. The influence of the donor-acceptor energy mismatch on the excess charge distribution, adiabatic dipole and transition moments, and electronic couplings is examined. A diagnostic is developed to determine whether the two-state approach can be applied. Based on numerical results, we showed that the superexchange correction considerably improves estimates of the donor-acceptor coupling derived within a two-state approach. In most cases when the two-state scheme fails, the formula gives reliable results which are in good agreement (within 5%) with the data of the three-state generalized Mulliken-Hush model
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The purpose of this research project is to study current practices in enhancing visibility and protection of highway maintenance vehicles involved in moving operations such as snow removal and shoulder operations, crack sealing, and pothole patching. The results will enable the maintenance staff to adequately assess the applicability and impact of each strategy to their use and budget. The report’s literature review chapter examines the use of maintenance vehicle warning lights, retroreflective tapes, shadow vehicles and truck-mounted attenuators, and advanced vehicle control systems, as well as other practices to improve visibility for both snowplow operators and vehicles. The chapter concludes that the Manual on Uniform Traffic Control Devices does not specify what color or kind of warning lights to use. Thus, a wide variety of lights are being used on maintenance vehicles. The study of the relevant literatures also suggests that there are no clear guidelines for moving work zones at this time. Two types of surveys were conducted to determine current practices to improve visibility and safety in moving work zones across the country and in the state of Iowa. In the first survey of state departments of transportation, most indicated using amber warning lights on their maintenance vehicles. Almost all the responding states indicated using some form of reflective material on their vehicles to make them more visible. Most participating states indicated that the color of their vehicles is orange. Most states indicated using more warning lights on snow removal vehicles than their other maintenance vehicles. All responding state agencies indicated using shadow vehicles and/or truck-mounted attenuators during their moving operations. In the second survey of Iowa counties, most indicated using very similar traffic control and warning devices during their granular road maintenance and snow removal operations. Mounting warning signs and rotating or strobe lights on the rear of maintenance vehicles is common for Iowa counties. The most common warning devices used during the counties’ snow removal operations are reflective tapes, warning flags, strobe lights, and auxiliary headlamps.
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We review the different meanings that researchers have given to theconcept of social capital, differentiate four types – bridging, bonding,linking, and overheads –, and discuss their different functions as public,club, and common goods.For each form of social capital we distinguish its productivity (acollective characteristic) from the factors that account for individual’sdifferential access to its returns, and propose alternative ways formeasuring each.We show the utility of our theoretical and measuring approach byanalyzing the impact of the each form of social capital on 15 year-oldstudents’ cognitive attainment across OECD countries, using 2006 PISAdata.The results show that students’ cognitive attainments are a direct functionof the richness or productivity of each form of social capital and ofstudents’ degree of access to each.
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The reaction of fluorinated fatty acids, perfluorobutyric acid (C3F7CO2H), and perfluorododecanoic acid (C11F23CO2H), with dodecacarbonyltriruthenium (Ru-3(CO)(12)) under reflux in tetrahydrofuran, followed by addition of two-electron donors (L) such as pyridine, 1,3,5-triaza-7-phosphatricyclo[3.3.1.1]decane, or triphenylphosphine, gives stable diruthenium complexes Ru-2(CO)(4)((2)-(2)-O2CC3F7)(2)(L)(2) (1a, L=C5H5N; 1b, L=PTA; 1c, L=PPh3) and Ru-2(CO)(4)((2)-(2)-O2CC11F23)(2)(L)(2) (2a, L=C5H5N; 2b, L=PTA; 2c, L=PPh3). The catalytic activity of the complexes for hydrogenation of styrene under supercritical carbon dioxide has been assessed and compared to the analogous triphenylphosphine complexes with non-fluorinated carboxylato groups Ru-2(CO)(4)((2)-(2)-O2CC3H7)(2)(PPh3)(2) (3) and Ru-2(CO)(4)((2)-(2)-O2CC11H23)(2)(PPh3)(2) (4). In addition, the cytotoxicities of the fluorinated complexes 1 were also evaluated on several human cancer cell lines (A2780, A549, Me300, HeLa). The complexes appear to be moderately cytotoxic, showing greater activity on the Me300 melanoma cells. Single-crystal X-ray structure analyses of 1a and 3 show the typical sawhorse-type arrangement of the diruthenium tetracarbonyl backbone with two bridging carboxylates and two terminal ligands occupying the axial positions.
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The Division of Criminal and Juvenile Justice Planning issued its first state legislation monitoring report in February 2002, covering the first six months’ impact of Senate File 543 (which enacted a number of sentencing changes) on the justice system; monitoring of the correctional impact of this bill was at the request of several members of the legislature. Since then, the Criminal and Juvenile Justice Planning Advisory Council has requested that CJJP monitor the correctional impact of enacted legislation of particular interest. This report covers monitoring results or future plans to monitor the following: 1. Changes in “crack” cocaine and “powder” cocaine penalties under Chapter 124.401 (effective FY2004; see p.3). 2. Commitments to prison involving manufacture, distribution, or possession of methamphetamine under Chapter 124.401 (see p.5). 3. Prosecution of offenders for child endangerment under Chapter 726.6(g) for permitting the presence of a child or minor at a location where a controlled substance manufacturing or a product possession violation occurs (see p.7). 4. Provision of an enhanced penalty for manufacturing of controlled substances under Chapter 124.401C when children are present and the offender is not charged under section 726.6(g) (see p. 7). 5. Creating a new offense when a retailer sells more than two packages of any product containing pseudoephedrine (chapter 126.23A) and providing for an enhanced penalty under Chapter 714.7C when a theft involves more than two packages of similar products (see p.8). 6. Establishment of parole eligibility at 70% of time served for persons sentenced under the “85% law” provisions of Iowa Code Section 902.12. (effective FY2005; see p. 9).