950 resultados para Midpoint Modulus of Local Convexity
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RESUME La radiothérapie est utilisée avec succès pour le traitement d'un grand nombre de pathologies tumorales (1). Cependant, les récidives post-actiniques sont associées à un risque accru de développer des métastases régionales et à distance (2, 3). La prise en charge de ce type de patients demeure insatisfaisante à l'heure actuelle, principalement parce que les mécanismes physio-pathologiques sous- sous-jacents restent mal compris. Etant donné le rôle primordial du stroma dans la progression tumorale (4) et l'importance des effets de la radiothérapie sur le micro-environnement des tumeurs (5), nous avons émis l'hypothèse que la radiothérapie pouvait engendrer des modifications stromales susceptibles de contribuer à l'émergence d'un phénotype tumoral plus agressif. Nous avons observé que l'exposition préalable d'un environnement tumoral à des radiations ionisantes engendre une inhibition locale et à long terme de l'angiogenèse. Cette inhibition conduit à la création d'un environnement tumoral hypoxique favorisant l'invasion et la métastatisation tumorale. Les mécanismes sous-jacents impliquent l'activation de gènes prométastatiques sous le contrôle du facteur de transcription HIF-1, ainsi que la sélection hypoxique de cellules hautement invasives et métastatiques. Par des analyses de profile d'expression génétique ainsi que par des analyses fonctionnelles, nous avons identifié la protéine matri-cellulaire CYR61 ainsi que ses partenaires d'interaction, les intégrines aVb5/aVb3, comme médiateurs importants de ces effets. De plus, une corrélation significative a également été trouvée entre le niveau d'expression de CYR61 et le taux d'hypoxie dans un grand nombre de carcinomes mammaires chez l'humain. Une association a aussi été observée entre le niveau d'expression de CYR61 et le pronostic de patientes souffrant d'un cancer du sein traité par chimiothérapie adjuvante. Globalement ces résultats identifient l'interaction entre la protéine CYR61 et ses récepteurs aVb5/aVb3 comme un mécanisme important du processus de métastatisation et en font une cible thérapeutique potentielle pour le traitement de patients souffrant d'une récidive tumorale après un traitement de radiothérapie. Finalement, bien que l'inhibition de l'angiogenèse soit locale dans ce cas particulier, nos résultats justifient une surveillance particulière des patients souffrant d'une pathologie tumorale et étant au bénéfice d'un traitement inhibiteur de l'angiogenèse. SUMMARY Radiotherapy is successfully used to treat a large variety of tumours (1 ). However, cancer patients experiencing local recurrent disease after radiation therapy are at increased risk of developing regional and distant metastasis (2, 3). The clinical management of this condition represents a difficult and challenging issue, mainly because the underlying physio-pathological mechanisms remain poorly understood. Given the well established role of the tumour stroma in promoting cancer progression (4) and since radiotherapy is known to persistently alter the tumour microenvironment (5), we hypothesized that ionising radiations may generate stromal modifications contributing to the metastatic spread of relapsing tumours. Here, we report that irradiation of the prospective tumour microenvironment promotes tumour invasion and metastasis through a mechanism of local and sustained impairment of angiogenesis leading to both HIF-1 dependent activation of pro-metastatic genes and hypoxia-mediated selection of highly metastatic tumour cell variants. Through gene expression profiling and functional experiments, we identified the matricellular signalling protein CYR61 and its interaction partners aVb5/ aVb3 integrins as critical mediators of these effects. Furthermore, we found a significant correlation between CYR61 expression and the hypoxic status of a large number of human mammary carcinomas. A positive correlation between increased levels of CYR61 expression and shorter relapse free survival was also identified in breast cancer patients treated with adjuvant chemotherapy. Together, these results identify CYR61 and aVb5/aVb3 integrins as critical mediators of metastasis and potential therapeutic targets to improve outcome in patients with post-radiation tumour recurrences. Finally, although inhibition of angiogenesis is local in this setting, our data warrant close monitoring of tumour progression in patients under anti-angiogenic therapy.
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OBJECTIVES: To investigate opinions' convergences and divergences of diabetic patients and health-care professionals on diabetes care and the development of a regional diabetes programme. BACKGROUND: Development and implementation of a regional diabetes programme. RESEARCH DESIGN: Qualitative study using focus groups to elicit diabetic patients' and health-care professionals' opinions, followed by content analysis. SETTING AND PARTICIPANTS: Eight focus groups: four focus groups with diabetic patients (n = 39) and four focus groups with various health-care professionals (n = 34) residing or practicing in the canton of Vaud, Switzerland, respectively. RESULTS: Perceived quality of diabetes care varied between individuals and types of participants. To improve quality, patients favoured a comprehensive follow-up while professionals suggested considering existing structures and trained professionals. All participants mentioned communication difficulties between professionals and were favouring teamwork. In addition, they described the role that patients should have in care and self-management. Financial difficulties were also mentioned by both groups of participants. Finally, they were in favour of the development of a regional diabetes programme adapted to actors' needs. For patients indeed, such a programme would represent an opportunity to improve information and to have access to comprehensive care. For professionals, it would help the development of local networks and the reinforcement of existing tools and structures. DISCUSSION AND CONCLUSIONS: Acknowledging convergences and divergences of opinions of both diabetic patients and health-care professionals should help the further development of a programme adapted to users' needs, taking all stakeholders interests and priorities into consideration.
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Overview. The Studies Committee received an in-person progress report from the consultants retained by the Legislature to conduct a study of the socioeconomic effects of gambling on Iowans. Dr. Deepak Chhabra and Dr. Gene Lutz, both of the University of Northern Iowa, presented an update on the conduct of the study. Gambling Study Description. The consultants indicated that the study objectives are to determine the economic impact of gambling at existing Iowa casinos on the local community, the socioeconomic characteristics of gamblers, the social impact of gambling on the local community, and the impact of problem gambling. The consultants stated that the major research methods they would use would be historical data, telephone surveys of local residents, telephone interviews with key personnel, and use of an economic impact model. In conducting the study, the consultants indicated they would examine four study areas within Iowa. Study area I would be all of Iowa, area II would be that area in Iowa within a 50-mile radius of a casino, area III would be counties with a casino, and area IV would be based upon casino employee zip codes. The consultants briefed the Committee on the data collected so far and described current challenges in obtaining data on all casino visitors and from obtaining information from several convention and visitor bureaus and chambers of commerce.
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PURPOSE: The Gastro-Intestinal Working Party of the EORTC Radiation Oncology Group (GIWP-ROG) developed guidelines for target volume definition in neoadjuvant radiation of adenocarcinomas of the gastroesophageal junction (GEJ) and the stomach. METHODS AND MATERIALS: Guidelines about the definition of the clinical target volume (CTV) are based on a systematic literature review of the location and frequency of local recurrences and lymph node involvement in adenocarcinomas of the GEJ and the stomach. Therefore, MEDLINE was searched up to August 2008. Guidelines concerning prescription, planning and treatment delivery are based on a consensus between the members of the GIWP-ROG. RESULTS: In order to support a curative resection of GEJ and gastric cancer, an individualized preoperative treatment volume based on tumour location has to include the primary tumour and the draining regional lymph nodes area. Therefore we recommend to use the 2nd English Edition of the Japanese Classification of Gastric Carcinoma of the Japanese Gastric Cancer Association which developed the concept of assigning tumours of the GEJ and the stomach to anatomically defined sub-sites corresponding respectively to a distinct lymphatic spread pattern. CONCLUSION: The GIWP-ROG defined guidelines for preoperative irradiation of adenocarcinomas of the GEJ and the stomach to reduce variability in the framework of future clinical trials.
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O trabalho que agora se apresenta é fruto, antes de mais, de uma relação especial com Timor. Não necessariamente pela dimensão histórica das várias presenças naquele território mas, e acima de tudo, pela relação pessoal e afectiva com alguns dos responsáveis políticos e religiosos daquele jovem país. Um convite, formulado em 2007 por Xanana Gusmão, levou-nos a calcorrear todo o território num curto espaço de três semanas, corria o Verão de 2008. O objectivo era a análise, no terreno, da viabilidade da instalação de um poder local num país recentemente tornado independente. Timor, fruto da sua história e, muito em especial, das características antropológicas do seu povo, é uma nação assumidamente multicultural. Das origens ancestrais das suas comunidades, dos reinos dispersos que pulverizam o pequeno território, das suas lideranças e dos vários dilectos, associados à longa e marcante presença portuguesa, bem como outras ocupações de países estrangeiros, com destaque para a Indonésia, resulta um caldo cultural, a todos os níveis peculiar. Aqui e acolá ouvimos o povo, entrevistámos e reunimos com os 432 chefes de suco existentes no país, entrevistámos chefes de aldeia e anciãos, reunimos com políticos, sacerdotes, professores e jornalistas. Interpretámos, ou tentámos interpretar, as condicionantes e os cuidados que se devem observar na preparação do quadro jurídico para reger a municipalidade em Timor: as suas vertentes electivas, funcionais, financeiras e fiscalizadoras. Revistámos a História de Timor e passámos por Cabo Verde, país de referência internacional ao nível da sua gestão pública, muito em especial a autárquica. Fizemos, também, óbvia referência à história do poder local em Portugal. Das consultas, do muito que observámos e estudámos, resulta um desinteressado contributo para a implementação do poder local em Timor, com as conclusões que incorporam alertas e sugestões.
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This study, now on presentation, comes as a result of a special relationship established with East Timor. Not necessarily through the several historical presences in that territory but, above all, through the emotional and personal relationships with some of the political and religious leaders of this young country. An invitation, made in 2007 by Xanana Gusmão, led us throughout the whole territory in a short time of three weeks, running the summer of 2008. Its purpose was the analysis, on the ground, of the possibility of installing local administration in a country which had recently became independent. Timor, as a result of its history, but mostly of the anthropological characteristics of its people, is an openly multicultural nation. The ancestral origins of their communities, its scattered kingdoms that spray along such a small territory, its leaders and many dialects, associated with the long portuguese presence, as well as other occupations made by foreign countries, especially Indonesia, became a cultural melting pot truly unique. Here and there we heard the people and interviewed and met the 432 local elected leaders of the country. We interviewed village elders and meet with politicians, priests, teachers and journalists. We have interpreted, or tried to, the actual conditions and cautions that must be observed in preparing the legal framework to govern the municipality in East Timor: its elective, functional, financial and oversight aspects. We have reviewed Timor’s history and took Cape Verde’s example as an international reference on its public administration, mostly its local authorities. We made also the obvious reference to the portuguese local government’s history. From search, and much of the observed and studied, remains a selfless contribution to the implementation of local government in East Timor, with alerts that incorporate conclusions and suggestions.
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This paper develops a model of job creation and job destruction in agrowing economy with embodied technical progress, that we use toanalyze the political support for employment protection legislationssuch as the ones that are observed in most European countries.We analyze the possibility of Condorcet cycles due to the fact thatworkers about to become unemployed prefer both an increase and areduction in firing costs over the status quo. Despite this problem, we show the existence of local, and sometimes global majority winners.In voting in favour of employment protection, incumbent employeestrade off lower living standards (because employment protectionmaintains workers in less productive activities) against longer job duration. We show that the gains from, and consequently the politicalsupport for employment protection (as defined by maximunjob tenure) are larger, the lower the rate of creative destruction and the largerthe worker's bargaining power. Numerical simulations suggest a hump-shaped response of firing costs to these variables, as well as negative impact of exogeneous turnover on employment protection.
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Learning has been postulated to 'drive' evolution, but its influence on adaptive evolution in heterogeneous environments has not been formally examined. We used a spatially explicit individual-based model to study the effect of learning on the expansion and adaptation of a species to a novel habitat. Fitness was mediated by a behavioural trait (resource preference), which in turn was determined by both the genotype and learning. Our findings indicate that learning substantially increases the range of parameters under which the species expands and adapts to the novel habitat, particularly if the two habitats are separated by a sharp ecotone (rather than a gradient). However, for a broad range of parameters, learning reduces the degree of genetically-based local adaptation following the expansion and facilitates maintenance of genetic variation within local populations. Thus, in heterogeneous environments learning may facilitate evolutionary range expansions and maintenance of the potential of local populations to respond to subsequent environmental changes.
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In the NE part of the Aiguilles Rouges Massif near Martigny, at the eastern contact of the Variscan Vallorcine granite to adjacent gneisses, a series of pitchblende (UO2)-veins occur. This paper determines the level of enrichment and mobility of uranium in soils situated in the vicinity of such a UO2-vein 7 km west of Martigny. Within an area of 50 x 100 m, situated on a relatively steep slope and characterized by a strong gramma-ray anomaly, six soil profiles including their plant cover and a reference soil profile outside the influence of the UO2-vein have been examined. The soil shows pH-values between 4 and 5 and is colluvial. The applied analytical methods for the metal contents include extraction methods, common for soil studies, and bulk analysis performed with X-ray fluorescence and ICP-MS. Uranium contents found in the uppermost 20 cm of the soil profiles vary from 2,500 ppm close to the vein to 15 ppm at the lowermost point of the study area. The reference soil has around 3 ppm uranium. At greater depth (20 to 40 cm) the U-content decreases to about half of the surface values, indicating a vertical transport of uranium within the soil profile. No systematic dependance of uranium-contents to grain size (amount of clay) nor to the amount of organic matter has been found. However, the good correlation between uranium and free iron oxide concentration suggests adsorption of uranium on iron oxy-hydroxides. The ashes of grass and mosses contain up to 90 ppm U, the blueberry and redwood only up to 3 ppm. Our observations suggest that at the surface the uranium is transported by downhill creep (solifluxion) of uranium-rich rock fragments. Liberated by oxidation of the uppermost fragments in a given soil column, the uranium migrates vertically until the conditions are favourable to adsorption onto Fe-oxy-hydroxides. However, as high U-contents of local surface water show, this adsorption does not lead to a significant retention of the uranium.
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Extinction, recolonization, and local adaptation are common in natural spatially structured populations. Understanding their effect upon genetic variation is important for systems such as genetically modified organism management or avoidance of drug resistance. Theoretical studies on the effect of extinction and recolonization upon genetic variance started appearing in the 1970s, but the role of local adaptation still has no good theoretical basis. Here we develop a model of a haploid species in a metapopulation in which a locally adapted beneficial allele is introduced. We study the effect of different spatial patterns of local adaptation, and different metapopulation dynamics, upon the fixation probability of the beneficial allele. Controlling for the average selection pressure, we find that a small area of positive selection can significantly increase the global probability of fixation. However, local adaptation becomes less important as extinction rate increases. Deme extinction and recolonization have a spatial smoothing effect that effectively reduces spatial variation in fitness.
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BACKGROUND: Endoresection of choroidal melanoma may offer the best hope of conserving vision in some patients but is controversial because of concerns regarding iatrogenic tumour dissemination. METHODS: Retrospective, non-randomised study of consecutive patients who underwent endoresection for choroidal melanoma at the Liverpool Ocular Oncology Centre between 1996 and 2010. RESULTS: The study included 71 patients with a mean age of 58.7 years. The tumour extended within 2 disc diameters of the optic disc in 46 (65%) eyes, involving the disc in 24 (34%) eyes. The mean largest basal tumour diameter and tumour thickness were 9.5 mm and 4.4 mm, respectively. The median follow-up was 4.1 years. The visual acuity at the latest follow-up was better than 6/30 in 31% eyes. The main causes of visual loss were foveal excision, rhegmatogenous retinal detachment (RD) and proliferative vitreo-retinopathy (PVR). Local recurrence developed in two patients (3%), who were treated by enucleation and proton beam radiotherapy, respectively. RD occurred in 16 cases (22%). Three (4%) eyes were enucleated, two because of PVR and one because of local tumour recurrence. Five patients died of metastatic disease. CONCLUSIONS: Endoresection achieved high rates of local tumour control. This operation would seem to be a useful alternative to radiotherapy as a means of conserving vision in eyes with juxtapapillary melanoma.
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Los nuevos hábitos de consumo de medios en el marco de la convergencia digital están propiciando un cambio en las estrategias de los medios de comunicación. Mientras unos usuarios siguen prefiriendo la radio, la televisión y la prensa tradicional para informarse otros participan de la experiencia digital en internet (blogs, redes sociales...) y dispositivos móviles, etc. En este panorama es complicado precisar dónde nace y termina el contenido o hasta qué punto es la participación del usuario quien (re) construye la información; así los contenidos mutan y se diluyen en varios soportes. En este contexto, la prensa local también vive las consecuencias del nuevo paradigma y asume los retos del reacomodo del sector ante la nueva realidad. Esta comunicación presenta las conclusiones del estudio cualitativo con entrevistas en profundidad a los responsables de medios locales en Cataluña sobre sus usuarios, contenidos y soportes en el marco de la convergencia digital.
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The provision of free appropriate public education (FAPE), an Individualized Education Program (IEP), and the least restrictive environment (LRE) have been important cornerstones of educating students with disabilities since the enactment of the Education of All Handicapped Children Act (EAHCA), Public Law 94-142, in 1975, and its subsequent reauthorizations, the Individuals with Disabilities Education Act (IDEA) in 1990, 1997, and 2004. It is impossible to consider any one of these cornerstones without the others, when determining an appropriate educational placement for a student with a disability. The Iowa Department of Education has identified several practice issues regarding the interplay between FAPE, LRE, and the IEP in placement decisions for students with disabilities. To that end, this document will provide guidance for administrators of local education agencies (LEAs) and area education agencies (AEAs), as well as IEP teams (or other placement teams) within Iowa LEAs and AEAs when making placement decisions for eligible children with disabilities. This guidance will specifically discuss ten LRE and FAPE placement/program policy questions that have been identified by the Iowa Department of Education as needing attention. The policy discussions are consistent with the legal provisions of the 2004 reauthorization of IDEA (IDEA 2004) and its 2006 final federal implementing regulations issued by the U.S. Department of Education, Office of Special Education Programs (OSEP). This document is also consistent with the Iowa Administrative Rules of Special Education (2007) [hereinafter “Iowa Rules”]. In addition, the term local education agency (LEA) is used interchangeably for school district throughout this document. Prior to the discussion of specific policy questions, a federal and state legal framework for providing FAPE for students with disabilities within the LRE is briefly outlined. Pertinent FAPE and LRE court decisions that impact Iowa LEAs and AEAs are also included within Section II.
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The State Long-Term Care Ombudsman program operates as a unit within the Iowa Department on Aging. Duties of all long-term care ombudsmen are mandated by the Older Americans Act. This office serves people living in nursing facilities, skilled nursing facilities, residential care facilities, nursing facilities in hospitals, elder group homes and assisted living programs. In order to carry out all of the mandates of the Older Americans Act this office recommends to increase the number of local long-term care ombudsman, develop a volunteer long-term care ombudsman program, clarify the definition of assisted living in Iowa, expand the long-term care ombudsman program into home and community based services, and reinstate the Iowa Office of Substitute Decision Maker.
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Commuting consists in the fact that an important fraction of workers in developed countries do not reside close to their workplaces but at long distances from them, so they have to travel to their jobs and then back home daily. Although most workers hold a job in the same municipality where they live or in a neighbouring one, an important fraction of workers face long daily trips to get to their workplace and then back home.Even if we divide Catalonia (Spain) in small aggregations of municipalities, trying to make them as close to local labour markets as possible, we will find out that some of them have a positive commuting balance, attracting many workers from other areas and providing local jobs for almost all their resident workers. On the other side, other zones seem to be mostly residential, so an important fraction of their resident workers hold jobs in different local labour markets. Which variables influence an area¿s role as an attraction pole or a residential zone? In previous papers (Artís et al, 1998a, 2000; Romaní, 1999) we have brought out the main individual variables that influence commuting by analysing a sample of Catalan workers and their commuting decisions. In this paper we perform an analysis of the territorial variables that influence commuting, using data for aggregate commuting flows in Catalonia from the 1991 and 1996 Spanish Population Censuses.These variables influence commuting in two different ways: a zone with a dense, welldeveloped economical structure will have a high density of jobs. Work demand cannot be fulfilled with resident workers, so it spills over local boundaries. On the other side, this economical activity has a series of side-effects like pollution, congestion or high land prices which make these areas less desirable to live in. Workers who can afford it may prefer to live in less populated, less congested zones, where they can find cheaper land, larger homes and a better quality of life. The penalty of this decision is an increased commuting time. Our aim in this paper is to highlight the influence of local economical structure and amenities endowment in the workplace-residence location decision. A place-to-place logit commuting models is estimated for 1991 and 1996 in order to find the economical and amenities variables with higher influence in commuting decisions. From these models, we can outline a first approximation to the evolution of these variables in the 1986-1996 period. Data have been obtained from aggregate flow travel-matrix from the 1986, 1991 and 1996 Spanish Population Censuses