860 resultados para shifting boundaries
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This article is concerned with the impact that federal structures have on the development of welfare to work or activation policies. More precisely, it argues that the incentives and the risks associated with a division of responsibilities among different jurisdictions may constitute an obstacle to broad reforms that promote labor market participation of nonworking benefit recipients. This argument is illustrated with a case study discussing policy responses to a massive rise in caseloads among social assistance recipients in Switzerland. We conclude that the lack of a fundamental reform was the consequence of the incentives provided by the federal structure of the program. These incentives have both encouraged cost shifting among jurisdictions and discouraged involvement of federal level policy makers in a bigger reform.
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OBJECTIVE To study the molecular genetic and clinical features of cerebral cavernous malformations (CCM) in a cohort of Spanish patients. METHODS We analyzed the CCM1, CCM2, and CCM3 genes by MLPA and direct sequencing of exons and intronic boundaries in 94 familial forms and 41 sporadic cases of CCM patients of Spanish extraction. When available, RNA studies were performed seeking for alternative or cryptic splicing. RESULTS A total of 26 pathogenic mutations, 22 of which predict truncated proteins, were identified in 29 familial forms and in three sporadic cases. The repertoire includes six novel non-sense and frameshift mutations in CCM1 and CCM3. We also found four missense mutations, one of them located at the third NPXY motif of CCM1 and another one that leads to cryptic splicing of CCM1 exon 6. We found four genomic deletions with the loss of the whole CCM2 gene in one patient and a partial loss of CCM1and CCM2 genes in three other patients. Four families had mutations in CCM3. The results include a high frequency of intronic variants, although most of them localize out of consensus splicing sequences. The main symptoms associated to clinical debut consisted of cerebral haemorrhage, migraines and epileptic seizures. The rare co-occurrence of CCM with Noonan and Chiari syndromes and delayed menarche is reported. CONCLUSIONS Analysis of CCM genes by sequencing and MLPA has detected mutations in almost 35% of a Spanish cohort (36% of familial cases and 10% of sporadic patients). The results include 13 new mutations of CCM genes and the main clinical symptoms that deserves consideration in molecular diagnosis and genetic counselling of cerebral cavernous malformations.
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In populations of various ant species, many queens reproduce in the same nest (polygyny), and colony boundaries appear to be absent with individuals able to move fi eely between nests (unicoloniality). Such societies depart strongly from a simple family structure and pose a potential challenge to kin selection theory, because high queen number coupled with unrestricted gene flow among nests should result in levels of relatedness among nestmates close to zero. This study investigated the breeding system and genetic structure of a highly polygynous and largely unicolonial population of the wood ant Formica paralugubris. A microsatellite analysis revealed that nestmate workers, reproductive queens and reproductive males (the queens' mates) are all equally related to each other, with relatedness estimates centring around 0.14. This suggests that most of the queens and males reproducing in the study population had mated within or close to their natal nest, and that the queens did not disperse far after mating. We developed a theoretical model to investigate how the breeding system affects the relatedness structure of polygynous colonies. By combining the model and our empirical data, it was estimated that about 99.8% of the reproducing queens and males originated from within the nest, or from a nearby nest. This high rate of local mating and the rarity of long-distance dispersal maintain significant relatedness among nestmates, and contrast with the common view that unicoloniality is coupled with unrestricted gene flow among nests.
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We propose a segmentation method based on the geometric representation of images as 2-D manifolds embedded in a higher dimensional space. The segmentation is formulated as a minimization problem, where the contours are described by a level set function and the objective functional corresponds to the surface of the image manifold. In this geometric framework, both data-fidelity and regularity terms of the segmentation are represented by a single functional that intrinsically aligns the gradients of the level set function with the gradients of the image and results in a segmentation criterion that exploits the directional information of image gradients to overcome image inhomogeneities and fragmented contours. The proposed formulation combines this robust alignment of gradients with attractive properties of previous methods developed in the same geometric framework: 1) the natural coupling of image channels proposed for anisotropic diffusion and 2) the ability of subjective surfaces to detect weak edges and close fragmented boundaries. The potential of such a geometric approach lies in the general definition of Riemannian manifolds, which naturally generalizes existing segmentation methods (the geodesic active contours, the active contours without edges, and the robust edge integrator) to higher dimensional spaces, non-flat images, and feature spaces. Our experiments show that the proposed technique improves the segmentation of multi-channel images, images subject to inhomogeneities, and images characterized by geometric structures like ridges or valleys.
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Evaluation of segmentation methods is a crucial aspect in image processing, especially in the medical imaging field, where small differences between segmented regions in the anatomy can be of paramount importance. Usually, segmentation evaluation is based on a measure that depends on the number of segmented voxels inside and outside of some reference regions that are called gold standards. Although some other measures have been also used, in this work we propose a set of new similarity measures, based on different features, such as the location and intensity values of the misclassified voxels, and the connectivity and the boundaries of the segmented data. Using the multidimensional information provided by these measures, we propose a new evaluation method whose results are visualized applying a Principal Component Analysis of the data, obtaining a simplified graphical method to compare different segmentation results. We have carried out an intensive study using several classic segmentation methods applied to a set of MRI simulated data of the brain with several noise and RF inhomogeneity levels, and also to real data, showing that the new measures proposed here and the results that we have obtained from the multidimensional evaluation, improve the robustness of the evaluation and provides better understanding about the difference between segmentation methods.
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The Barcelona Euro-Mediterranean Conference (1995) was intended to be a launching pad" for creating a new, innovative relationship between the EU-Fifteen and a selected set of non-member Middle Eastern and North African countries. The Barcelona Process was to become the European Union´s first attempt, of several, to create postmodern inclusive policy spheres as a way to deal with the post-enlargement problems of ´ins´ and outs´ in its immediate periphery. Nevertheless, in spite of geographical proximity, common problems and stated interest in creating amorphous EU borders in different sectors, the Euro-Mediterranean Partnership is today all but abandoned. This paper will examine some of the factors behind the current degeneration of the EU´s post-bipolar foreign policy strategy in the Mediterranean, by exploring the dialectic between the Union´s desire to expand its geopolitical, economic and cultural boundaries and the need to secure its territorial area (from migration, proliferation, social instability etc.). In the final part of the paper some suggestions for how to revive the relationship across the Mare Nostrum will be forwarded.
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This article discusses the construction of tri-sector partnerships in three projects conducted in Brazil in different fields of intervention of public policy (access to water, basic education and performance of boards of rights of children and adolescents). Collaborative articulations involving the players from three sectors (the State, civil society and the market) are practices that are little studied in the Brazilian and even in the international context, as tri-sector partnerships are rare, despite the proliferation of lines of discourse in support of alliances between governments and civil society or between companies and NGOs in the management of public policy. As a research strategy, this study resorted to cooperative inquiry, a method that involves breaking down the boundaries between the subjects and the objects of the analysis. Besides working toward a better understanding of the challenges of building tri-sector partnerships in the Brazilian context, the article also tries to show the relevance to public policy studies of investigative methods based on the subjects studied, as a means of developing an understanding of the practices, lines of discourse and dilemmas linked to social action in social programs.
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One of the world's largest wollastonite deposits was formed at the contact of the northern Hunter Mountain Batholith (California, USA) in Paleozoic sediments. Wollastonite occurs as zones of variable thickness surrounding layers or nodules of quartzite in limestones. A minimum formation temperature of 650 degrees C is estimated from isolated periclase-bearing lenses in that area. Contact metamorphism of siliceous carbonates has produced mineral assemblages that are consistent with heterogeneous, and partly limited infiltration of water-rich fluids, compatible with O-18/O-16 and C-13/C-12 isotopic patterns recorded in carbonates. Oxygen isotope compositions of wollastonites in the study area may also not require infiltration of large quantities of externally-derived fluids that were out of equilibrium with the rocks. 8180 values of wollastonite are high (14.8 parts per thousand to 25.0 parts per thousand; median: 19.7 parts per thousand) and close to those of the host limestone (19.7 parts per thousand to 28 parts per thousand; median: 24.9 parts per thousand) and quartz (18.0 parts per thousand. to 29.1 parts per thousand; median: 22.6 parts per thousand). Isotopic disequilibrium exists at quartz/wollastonite and wollastonite/calcite boundaries. Therefore, classical batch/Rayleigh fractionation models based on reactant and product equilibrium are not applicable to the wollastonite rims. An approach that relies on local instantaneous mass balance for the reactants, based on the wollastonite-forming reaction is suggested as an alternative way to model wollastonite reaction rims. This model reproduces many of the measured delta O-18 values of wollastonite reaction rims of the current study to within +/- 1 parts per thousand, even though the wollastonite compositions vary by almost 10 parts per thousand. (C) 2011 Elsevier B.V. All rights reserved.
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We construct a dynamic theory of civil conflict hinging on inter-ethnic trust and trade. The model economy is inhabitated by two ethnic groups. Inter-ethnic trade requires imperfectly observed bilateral investments and one group has to form beliefs on the average propensity to trade of the other group. Since conflict disrupts trade, the onset of a conflict signals that the aggressor has a low propensity to trade. Agents observe the history of conflicts and update their beliefs over time, transmitting them to the next generation. The theory bears a set of testable predictions. First, war is a stochastic process whose frequency depends on the state of endogenous beliefs. Second, the probability of future conflicts increases after each conflict episode. Third, "accidental" conflicts that do not reflect economic fundamentals can lead to a permanent breakdown of trust, plunging a society into a vicious cycle of recurrent conflicts (a war trap). The incidence of conflict can be reduced by policies abating cultural barriers, fostering inter-ethnic trade and human capital, and shifting beliefs. Coercive peace policies such as peacekeeping forces or externally imposed regime changes have instead no persistent effects.
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Social capital is viewed either as a proprietary asset that serves private interests, including those of entrepreneurs, or as a collective asset that supports trust-based transactions saving on transaction costs both in markets and within the boundaries of firms, and benefiting society as a whole. This paper explains the relative specialization between entrepreneurs and market-governed exchanges as a result of the interaction between social capital that lowers transaction costs, and the scale economies of ability in managerial jobs (Lucas 1978). The main hypothesis formulated in the paper is that higher social capital will benefit the hierarchy relatively more than the market as a governance mechanism, and therefore in economies with higher social capital, the equilibrium number of entrepreneurs will be lower and their average span of control larger than in economies with lower social capital. The empirical evidence, with data from the Spanish Autonomous Communities, is consistent with this prediction.
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BACKGROUND: Highly recurrent major depressive disorder (MDD) has reportedly increased risk of shifting to bipolar disorder; high recurrence frequency has, therefore, featured as evidence of 'soft bipolarity'. We aimed to investigate the genetic underpinnings of total depressive episode count in recurrent MDD. METHODS: Our primary sample included 1966 MDD cases with negative family history of bipolar disorder from the RADIANT studies. Total episode count was adjusted for gender, age, MDD duration, study and center before being tested for association with genotype in two separate genome-wide analyses (GWAS), in the full set and in a subset of 1364 cases with positive family history of MDD (FH+). We also calculated polygenic scores from the Psychiatric Genomics Consortium MDD and bipolar disorder studies. RESULTS: Episodicity (especially intermediate episode counts) was an independent index of MDD familial aggregation, replicating previous reports. The GWAS produced no genome-wide significant findings. The strongest signals were detected in the full set at MAGI1 (p=5.1×10(-7)), previously associated with bipolar disorder, and in the FH+ subset at STIM1 (p=3.9×10(-6) after imputation), a calcium channel signaling gene. However, these findings failed to replicate in an independent Munich cohort. In the full set polygenic profile analyses, MDD polygenes predicted episodicity better than bipolar polygenes; however, in the FH+ subset, both polygenic scores performed similarly. LIMITATIONS: Episode count was self-reported and, therefore, subject to recall bias. CONCLUSIONS: Our findings lend preliminary support to the hypothesis that highly recurrent MDD with FH+ is part of a 'soft bipolar spectrum' but await replication in larger cohorts.
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Cette thèse, qui se base sur des entretiens qualitatifs, porte sur la négociation des références identitaires de musulmans immigrés et réfugiés en provenance de Γ ex-Yougoslavie au Luxembourg et s'intéresse à la pertinence changeante de la religion dans la conception de soi. Selon une approche constructiviste et interactionniste, l'identité est conçue comme un projet constamment négocié, reconstruit dans des processus d'interaction sociale et en fonction des contextes sociaux. Nos données suggèrent l'émergence de constructions identitaires complexes et attestent de la pluridimensionalité et de l'intersectionnalité des références identitaires utilisées dans la conception de soi et témoignent de la non-réduction des individus à des catégories fixes. Différentes catégories sont rendues significatives et de multiples frontières sont établies afin de se différencier de figures d'altérité changeantes, sélectivement choisies pour construire une certaine image de soi. Les discours identitaires témoignent de l'aspiration à une identité positive, dans une situation caractérisée par la perte du statut social et des stigmatisations multiples, en tant que ex-Yougoslaves, demandeurs d'asile et musulmans. Nos interlocuteurs établissent un répertoire identitaire composé de marqueurs transposés, inventés et revalorisés, leur permettant de reconstruire une identité positive pour soi et leurs audiences. Ce travail décrit les manières dont les individus établissent leur répertoire identitaire à l'aide de marqueurs transposés, inventés et revalorisés, leur permettant de reconstruire une identité positive pour soi et leurs audiences et montre comment les processus de différenciation de 'l'autre' dans le pays d'origine et d'accueil sont reliés. - The question addressed in this project with a qualitative design, is how muslim migrants and refugees from the former Socialist Federal Republic of Yugoslavia in Luxemburg negotiate salient identity references in a new social political environment and discusses the changing significance of religion and the way it is integrated in the identity patchwork. According to a constructivist and interactionist approach, conceiving identity as a constantly negotiated project, reconstructed in interaction and with regard to social context, identities are relevant only in relation to particular other groups and in certain situations of interaction. Our data suggest the emergence of complex identity patterns using multiple references for self- description and attest of the intersectionnality of identity references and show that individuals can't be reduced to fixed categories. Different categories are made salient and multiple symbolic boundaries are established in order to differentiate from different "others", selected in order to construct a certain self-concept. The discourses of our participants attest of an aspiration towards a positive identity in a situation characterized by the loss of social status and multiple stigmata. This thesis describes the ways how individuals establish their identity repertoire with invented, transposed and negotiated identity references, that allow them to construct a favourable identity for themselves and their public and shows how différenciation processes in home and host country are related.
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Nowadays, the joint exploitation of images acquired daily by remote sensing instruments and of images available from archives allows a detailed monitoring of the transitions occurring at the surface of the Earth. These modifications of the land cover generate spectral discrepancies that can be detected via the analysis of remote sensing images. Independently from the origin of the images and of type of surface change, a correct processing of such data implies the adoption of flexible, robust and possibly nonlinear method, to correctly account for the complex statistical relationships characterizing the pixels of the images. This Thesis deals with the development and the application of advanced statistical methods for multi-temporal optical remote sensing image processing tasks. Three different families of machine learning models have been explored and fundamental solutions for change detection problems are provided. In the first part, change detection with user supervision has been considered. In a first application, a nonlinear classifier has been applied with the intent of precisely delineating flooded regions from a pair of images. In a second case study, the spatial context of each pixel has been injected into another nonlinear classifier to obtain a precise mapping of new urban structures. In both cases, the user provides the classifier with examples of what he believes has changed or not. In the second part, a completely automatic and unsupervised method for precise binary detection of changes has been proposed. The technique allows a very accurate mapping without any user intervention, resulting particularly useful when readiness and reaction times of the system are a crucial constraint. In the third, the problem of statistical distributions shifting between acquisitions is studied. Two approaches to transform the couple of bi-temporal images and reduce their differences unrelated to changes in land cover are studied. The methods align the distributions of the images, so that the pixel-wise comparison could be carried out with higher accuracy. Furthermore, the second method can deal with images from different sensors, no matter the dimensionality of the data nor the spectral information content. This opens the doors to possible solutions for a crucial problem in the field: detecting changes when the images have been acquired by two different sensors.
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Discussions at the inaugural meeting of a Trans-European Pedagogic Research Group for Anatomical Sciences highlighted the fact that there exist considerable variations in the legal and ethical frameworks throughout Europe concerning body bequests for anatomical examination. Such differences appear to reflect cultural and religious variations as well as different legal and constitutional frameworks. For example, there are different views concerning the "ownership" of cadavers and concerning the need (perceived by different societies and national politicians) for legislation specifically related to anatomical dissection. Furthermore, there are different views concerning the acceptability of using unclaimed bodies that have not given informed consent. Given that in Europe there have been a series of controversial anatomical exhibitions and also a public (televised) dissection/autopsy, and given that the commercial sale or transport of anatomical material across national boundaries is strongly debated, it would seem appropriate to "harmonise" the situation (at least in the European Union). This paper summarises the legal situation in a variety of European countries and suggests examples of good practice. In particular, it recommends that all countries should adopt clear legal frameworks to regulate the acceptance of donations for medical education and research. It stresses the need for informed consent, with donors being given clear information upon which to base their decision, intentions to bequest being made by the donor before death and encourages donors to discuss their wishes to bequeath with relatives prior to death. Departments are encouraged, where they feel it appropriate, to hold Services of Thanksgiving and Commemoration for those who have donated their bodies. Finally, there needs to be legislation to regulate transport of bodies or body parts across national borders and a discouragement of any moves towards commercialisation in relation to bequests.
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Neurofilaments are typical structures of the neuronal cytoskeleton and participate in the formation and stabilization of the axonal and dendritic architecture. In this study, we have characterized a murine monoclonal antibody, FNP7, that is directed against the medium-sized neurofilament subunit NF-M. This antibody identifies a subset of neurons in the cerebral cortex of various species including human and in organotypic cultures of rat cortex. In the neocortex of all species examined, the antibody labels pyramidal cells in layers III, V, and VI, with a distinctive laminar distribution between architectonic boundaries. In comparison with other antibodies directed against NF-M, the FNP7 antibody identifies on blots two forms of NF-M that appear relatively late during development, at the time when dynamic growth of processes changes to the stabilization of the formed processes. Dephosphorylation with alkaline phosphatase unmasks the site, making it detectable for the FNP7 antibody. The late appearance suggests that the site is present during early development in phosphorylated form and with increasing maturation becomes dephosphorylated, mainly in dendrites. This event may relate to changes in cytoskeleton stability in a late phase of dendritic maturation. Furthermore, mainly corticofugal projections and only few callosal axons are stained, suggesting a differential phosphorylation in a subset of axons. The antibody provides a useful marker to study subsets of pyramidal cells in vivo, in vitro, and under experimental conditions.