945 resultados para servo drive
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This analysis is a follow-up to an earlier investigation of 182 genes selected as likely candidate genetic variations conferring susceptibility to anorexia nervosa (AN). As those initial case-control results revealed no statistically significant differences in single nucleotide polymorphisms, herein, we investigate alternative phenotypes associated with AN. In 1762 females, using regression analyses, we examined the following: (i) lowest illness-related attained body mass index; (ii) age at menarche; (iii) drive for thinness; (iv) body dissatisfaction; (v) trait anxiety; (vi) concern over mistakes; and (vii) the anticipatory worry and pessimism versus uninhibited optimism subscale of the harm avoidance scale. After controlling for multiple comparisons, no statistically significant results emerged. Although results must be viewed in the context of limitations of statistical power, the approach illustrates a means of potentially identifying genetic variants conferring susceptibility to AN because less complex phenotypes associated with AN are more proximal to the genotype and may be influenced by fewer genes. Copyright © 2011 John Wiley & Sons, Ltd and Eating Disorders Association.
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Transportation is an important health care issue. The majority of the population here in Iowa have ready access and typically use private automobiles to access health care and other community services. There is also a significant segment of the population that either does not have access to a personal automobile or is not currently capable of driving. This can potentially limit their access to health care, but it has greater health implications because it can also limit access to nutrition and other community services, as well as involvement in social activities. For people unable to drive themselves, the alternatives generally include reliance on family, friends, volunteer groups, and public transit. Many choose transit because it gives them a degree of independence. Public transit is often used to supplement other options even when they are available. It becomes critical in circumstances where the other options don’t exist. In many cases there may be no family available or they may not always be able to get off work when travel needs arise during the workday. Friends may be in similar circumstances and volunteer groups may be either unavailable or overwhelmed. The fact that many patients depend on public transit to get to and from health care appointments makes it beneficial for health care professionals to get to know more about public transit and how it operates here in Iowa.
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We investigate the coevolution between philopatry and altruism in island-model populations when kin recognition occurs through phenotype matching. In saturated environments, a good discrimination ability is a necessary prerequisite for the emergence of sociality. Discrimination decreases not only with the average phenotypic similarity between immigrants and residents (i.e., with environmental homogeneity and past gene flow) but also with the sampling variance of similarity distributions (a negative function of the number of traits sampled). Whether discrimination should rely on genetically or environmentally determined traits depends on the apportionment of phenotypic variance and, in particular, on the relative values of e (the among-group component of environmental variance) and r (the among-group component of genetic variance, which also measures relatedness among group members). If r exceeds e, highly heritable cues do better. Discrimination and altruism, however, remain low unless philopatry is enforced by ecological constraints. If e exceeds r, by contrast, nonheritable traits do better. High e values improve discrimination drastically and thus have the potential to drive sociality, even in the absence of ecological constraints. The emergence of sociality thus can be facilitated by enhancing e, which we argue is the main purpose of cue standardization within groups, as observed in many social insects, birds, and mammals, including humans.
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Cette thèse cible l'étude de la structure thermique de la croûte supérieure (<10km) dans les arcs magmatiques continentaux, et son influence sur l'enregistrement thermochronologique de leur exhumation et de leur évolution topographique. Nous portons notre regard sur deux chaînes de montagne appartenant aux Cordillères Américaines : Les Cascades Nord (USA) et la zone de faille Motagua (Guatemala). L'approche utilisée est axée sur la thermochronologie (U-Th-Sm)/He sur apatite et zircon, couplée avec la modélisation numérique de la structure thermique de la croûte. Nous mettons en évidence la variabilité à la fois spatiale et temporelle du gradient géothermique, et attirons l'attention du lecteur sur l'importance de prendre en compte la multitude des processus géologiques perturbant la structure thermique dans les chaînes de type cordillère, c'est à dire formées lors de la subduction océanique sous un continent.Une nouvelle approche est ainsi développée pour étudier et contraindre la perturbation thermique autour des chambres magmatiques. Deux profiles âge-elevation (U-Th-Sm)/He sur apatite et zircon, ont été collectées 7 km au sud du batholithe de Chilliwack, Cascades Nord. Les résultats montrent une variabilité spatiale et temporelle du gradient géothermique lors de l'emplacement magmatique qui peut être contrainte et séparé de l'exhumation. Durant l'emplacement de l'intrusion, la perturbation thermique y atteint un état d'équilibre (-80-100 °C/km) qui est fonction du flux de magma et de ia distance à la source du magma, puis rejoint 40 °C/km à la fin du processus d'emplacement magmatique.Quelques nouvelles données (U-Th)/He, replacées dans une compilation des données existantes dans les Cascades Nord, indiquent une vitesse d'exhumation constante (-100 m/Ma) dans le temps et l'espace entre 35 Ma et 2 Ma, associée à un soulèvement uniforme de la chaîne contrôlé par l'emplacement de magma dans la croûte durant toute l'activité de l'arc. Par contre, après ~2 Ma, le versant humide de la chaîne est affecté par une accélération des taux d'exhumation, jusqu'à 3 km de croûte y sont érodés. Les glaciations ont un triple effet sur l'érosion de cette chaîne: (1) augmentation des vitesses d'érosion, d'exhumation et de soulèvement la où les précipitations sont suffisantes, (2) limitation de l'altitude contrôlé par la position de Γ Ε LA, (3) élargissement du versant humide et contraction du versant aride de la chaîne.Les modifications des réseaux de drainage sont des processus de surface souvent sous-estimés au profil d'événements climatiques ou tectoniques. Nous proposons une nouvelle approche couplant une analyse géomorphologique, des données thermochronologiques de basse température ((U-Th-Sm)/He sur apatite et zircon), et l'utilisation de modélisation numérique thermo-cinématique pour les mettre en évidence et les dater; nous testons cette approche sur la gorge de la Skagit river dans les North Cascades.De nouvelles données (U-Th)/He sur zircons, complétant les données existantes, montrent que le déplacement horizontal le long de la faille transformante continentale Motagua, la limite des plaques Caraïbe/Amérique du Nord, a juxtaposé un bloc froid, le bloc Maya (s.s.), contre un bloque chaud, le bloc Chortis (s.s.) originellement en position d'arc. En plus de donner des gammes d'âges thermochronologiques très différents des deux côtés de la faille, le déplacement horizontal rapide (~2 cm/a) a produit un fort échange thermique latéral, résultant en un réchauffement du côté froid et un refroidissement du côté chaud de la zone de faille de Motagua.Enfin des données (U-Th-Sm)/He sur apatite témoignent d'un refroidissement Oligocène enregistré uniquement dans la croûte supérieure de la bordure nord de la zone de faille Motagua. Nous tenterons ultérieurement de reproduire ce découplage vertical de la structure thermique par la modélisation de la formation d'un bassin transtensif et de circulation de fluides le long de la faille de Motagua. - This thesis focuses on the influence of the dynamic thermal structure of the upper crust (<10km) on the thermochronologic record of the exhumational and topographic history of magmatic continental arcs. Two mountain belts from the American Cordillera are studied: the North Cascades (USA) and the Motagua fault zone (Guatemala). I use a combined approach coupling apatite and zircon (U-Th-Sm}/He thermochronology and thermo- kinematic numerical modelling. This study highlights the temporal and spatial variability of the geothermal gradient and the importance to take into account the different geological processes that perturb the thermal structure of Cordilleran-type mountain belts (i.e. mountain belts related to oceanic subduction underneath a continent}.We integrate apatite and zircon (U-Th)/He data with numerical thermo-kinematic models to study the relative effects of magmatic and surface processes on the thermal evolution of the crust and cooling patterns in the Cenozoic North Cascades arc (Washington State, USA). Two age-elevation profiles that are located 7 km south of the well-studied Chiliiwack intrusions shows that spatial and temporal variability in geothermal gradients linked to magma emplacement can be contrained and separated from exhumation processes. During Chiliiwack batholith emplacement at -35-20 Ma, the geothermal gradient of the country rocks increased to a very high steady-state value (80-100°C/km), which is likely a function of magma flux and the distance from the magma source area. Including temporally varying geothermal gradients in the analysis allows quantifying the thermal perturbation around magmatic intrusions and retrieving a relatively simple denudation history from the data.The synthesis of new and previously published (U-Th)/He data reveals that denudation of the Northern Cascades is spatially and temporally constant at -100 m/Ma between ~32 and ~2 Ma, which likely reflects uplift due to magmatic crustal thickening since the initiation of the Cenozoic stage of the continental magmatic arc. In contrast, the humid flank of the North Cascades is affected by a ten-fold acceleration in exhumation rate at ~2 Ma, which we interpret as forced by the initiation of glaciations; around 3 km of crust have been eroded since that time. Glaciations have three distinct effects on the dynamics of this mountain range: (1) they increase erosion, exhumation and uplift rates where precipitation rates are sufficient to drive efficient glacial erosion; (2) they efficiently limit the elevation of the range; (3) they lead to widening of the humid flank and contraction of the arid flank of the belt.Drainage reorganizations constitute an important agent of landscape evolution that is often underestimated to the benefit of tectonic or climatic events. We propose a new method that integrates geomorphology, low-temperature thermochronometry (apatite and zircon {U-Th-Sm)/He), and 3D numerical thermal-kinematic modelling to detect and date drainage instability producing recent gorge incision, and apply this approach to the Skagit River Gorge, North Cascades.Two zircon (U-Th)/He age-elevation profiles sampled on both sides of the Motagua Fault Zone (MFZ), the boundary between the North American and the Caribbean plates, combined with published thermochronological data show that strike-slip displacement has juxtaposed the cold Maya block (s.s.) against the hot, arc derived, Chortis block (s.s ), producing different age patterns on both sides of the fault and short-wavelength lateral thermal exchange, resulting in recent heating of the cool side and cooling of the hot side of the MFZ.Finally, an apatite (U-Th-Sm)/He age-elevation profile records rapid cooling at -35 Ma localized only in the upper crust along the northern side of the Motagua fault zone. We will try to reproduce these data by modeling the thermal perturbation resulting from the formation of a transtensional basin and of fluid flow activity along a crustal- scale strike-slip fault.
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Les Pays-Bas et la Suisse sont souvent décrits comme ayant des relations entre travail et capital similaires, marquées par des négociations et le compromis. La conviction est courante dans les deux pays qu'il y a une tendance constante au consensus et au compromis dans l'histoire nationale. Cette thèse livre une comparaison historique du développement des relations de classe dans la 1ers moitié du 20eme siècle. Une attention particulière est donnée aux confrontations sévères et partiellement violentes entre les classes qui ont eu lieu pendant et juste après la Première Guerre Mondiale. Dans la crise des années trente, les deux pays ont longtemps maintenu l'attachement à une politique de déflation, ce qui a mené à une nouvelle accentuation des tensions sociales. Dans ce contexte, loin d'être prêts à faire des concessions au mouvement ouvrier, d'importantes composantes du patronat néerlandais et suisse sympathisaient avec un corporatisme autoritaire comme il était prôné par les mouvements et régimes fascistes. Des alliances entre le mouvement ouvrier socialiste et des fractions importantes des classes moyennes étaient capables d'arrêter cette dérive autoritaire, sans avoir assez de force pour imposer leurs propres alternatives. C'est seulement après l'affaiblissement de la droite dure entre la deuxième moitié des années trente et l'immédiat après-guerre que des premiers fondements pour un compromis de classe stable ont été établis. Généralement, l'approche comparée de la thèse permet de mieux saisir les histoires nationales dans leur contexte européen et global et permet donc de dépasser une vue de l'histoire nationale comme «cas spécial».¦Die Beziehungen zwischen Arbeit und Kapital in Niederlande und die Schweiz werden oft als âhnlich und stark von Verhandlungen und von Kompromissen geprâgt beschrieben. In beiden Lândern ist die Auffassung weitverbreitet, dass es in der nationalen Geschichte eine konstante Tendenz zum Konsens und zum Kompromiss gebe. Diese Dissertation bietet einen historischen Vergleich der Entwicklung der Klassenbeziehungen in der ersten Hâlfte des 20. Jahrhunderts. Thematisiert werden insbesondere die ernsthaften und teilweise gewalttàtigen Zusammenstôsse zwischen den Klassen, die sich wàhrend und unmittelbar nach dem Ersten Weltkrieg ereigneten. In der Krise der Dreissigerjahre hielten beide Staaten lange an der Deflationspolitik fest, was erneut zu einer Verschârfung der sozialen Spannungen fïïhrte. Vor diesem Hintergrund lehnten weite Teile der schweizerischen und niederlândischen Grossunternehmer Konzessionen gegenuber der Arbeiterbewegung ab. Vielmehr sympathisierten sie mit einem autoritàren Korporatismus, wie er von den faschistischen Bewegungen und Regimes vertreten wurde. Allianzen zwischen der sozialistischen Arbeiterbewegung und Teilen der Mittelschichten gelang es zwar, diese autoritàren Tendenzen aufzuhalten, nicht aber ihre eigenen Alteraativkonzepte durchzusetzen. Erst nach der Schwâchung der radikalen Rechten in der Zeit zwischen der zweiten Hàlfte der 1930er Jahre und der unmittelbaren Nachkriegszeit nach dem Zweiten Weltkrieg fand sich eine¦Grundlage fur einen stabilen Klassenkompromiss. Generell ermôglicht es der vergleichende Ansatz der Dissertation, die nationale Geschichte in ihrem europâischen und globalen Kontext zu sehen und so eine Sicht auf die Geschichte eines einzelnen Landes als ,,Sonderfall" zu uberwinden.
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In this study we report that, in response to proteasome inhibition, the E3-Ubiquitin ligase TRIM50 localizes to and promotes the recruitment and aggregation of polyubiquitinated proteins to the aggresome. Using Hdac6-deficient mouse embryo fibroblasts (MEF) we show that this localization is mediated by the histone deacetylase 6, HDAC6. Whereas Trim50-deficient MEFs allow pinpointing that the TRIM50 ubiquitin-ligase regulates the clearance of polyubiquitinated proteins localized to the aggresome. Finally we demonstrate that TRIM50 colocalizes, interacts with and increases the level of p62, a multifunctional adaptor protein implicated in various cellular processes including the autophagy clearance of polyubiquitinated protein aggregates. We speculate that when the proteasome activity is impaired, TRIM50 fails to drive its substrates to the proteasome-mediated degradation, and promotes their storage in the aggresome for successive clearance.
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The problem of small Island Developing States (SIDS) is quite recent, end of the 80s and 90s, still looking for a theoretical consolidation. SIDS, as small states in development, formed by one or several islands geographically dispersed, present reduced population, market, territory, natural resources, including drinkable water, and, in great number of the cases, low level of economic activity, factors that together, hinder the gathering of scale economies. To these diseconomies they come to join the more elevated costs in transports and communications which, allies to lower productivities, to a smaller quality and diversification of its productions, which difficult its integration in the world economy. In some SIDS these factors are not dissociating of the few investments in infrastructures, in the formation of human resources and in productive investments, just as it happens in most of the developing countries. In ecological terms, many of them with shortage of natural resources, but integrating important ecosystems in national and world terms, but with great fragility relatively to the pollution action, of excessive fishing, of uncontrolled development of tourism, factors that, conjugated and associated to the stove effect, condition the climate and the slope of the medium level of the sea water and therefore could put in cause the own survival of some of them. The drive to the awareness of the international community towards its problems summed up with the accomplishment by the United Nations in the Barbados’s Conference, 1994 where the right to the development was emphasized, through the going up the appropriate strategies and the Programme of Action for the Sustainable Development of the SIDS. The orientation of the regional and international cooperation in that sense, sharing technology (namely clean technology and control and administration environmental technology), information and creation of capacity-building, supplying means, including financial resources, creating non discriminatory and just trade rules, it would drive to the establishment of a world system economically more equal, in which the production, the consumption, the pollution levels, the demographic politics were guided towards the sustainability. It constituted an important step for the recognition for the international community on the specificities of those states and it allowed the definition of a group of norms and politics to implement at the national, regional and international level and it was important that they continued in the sense of the sustainable development. But this Conference had in its origin previous summits: the Summit of Rio de Janeiro about Environment and Development, accomplished in 1992, which left an important document - the Agenda 21, in the Conference of Stockholm at 1972 and even in the Conference of Ramsar, 1971 about “Wetlands.” CENTRO DE ESTUDOS AFRICANOS Occasional Papers © CEA - Centro de Estudos Africanos 4 Later, the Valletta Declaration, Malta, 1998, the Forum of Small States, 2002, get the international community's attention for the problems of SIDS again, in the sense that they act to increase its resilience. If the definition of “vulnerability” was the inability of the countries to resist economical, ecological and socially to the external shocks and “resilience” as the potential for them to absorb and minimize the impact of those shocks, presenting a structure that allows them to be little affected by them, a part of the available studies, dated of the 90s, indicate that the SIDS are more vulnerable than the other developing countries. The vulnerability of SIDS results from the fact the they present an assemblage of characteristics that turns them less capable of resisting or they advance strategies that allow a larger resilience to the external shocks, either anthropogenic (economical, financial, environmental) or even natural, connected with the vicissitudes of the nature. If these vulnerability factors were grouped with the expansion of the economic capitalist system at world level, the economic and financial globalisation, the incessant search of growing profits on the part of the multinational enterprises, the technological accelerated evolution drives to a situation of disfavour of the more poor. The creation of the resilience to the external shocks, to the process of globalisation, demands from SIDS and of many other developing countries the endogen definition of strategies and solid but flexible programs of integrated development. These must be assumed by the instituted power, but also by the other stakeholders, including companies and organizations of the civil society and for the population in general. But that demands strong investment in the formation of human resources, in infrastructures, in investigation centres; it demands the creation capacity not only to produce, but also to produce differently and do international marketing. It demands institutional capacity. Cape Verde is on its way to this stage.
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PURPOSE: Most existing methods for accelerated parallel imaging in MRI require additional data, which are used to derive information about the sensitivity profile of each radiofrequency (RF) channel. In this work, a method is presented to avoid the acquisition of separate coil calibration data for accelerated Cartesian trajectories. METHODS: Quadratic phase is imparted to the image to spread the signals in k-space (aka phase scrambling). By rewriting the Fourier transform as a convolution operation, a window can be introduced to the convolved chirp function, allowing a low-resolution image to be reconstructed from phase-scrambled data without prominent aliasing. This image (for each RF channel) can be used to derive coil sensitivities to drive existing parallel imaging techniques. As a proof of concept, the quadratic phase was applied by introducing an offset to the x(2) - y(2) shim and the data were reconstructed using adapted versions of the image space-based sensitivity encoding and GeneRalized Autocalibrating Partially Parallel Acquisitions algorithms. RESULTS: The method is demonstrated in a phantom (1 × 2, 1 × 3, and 2 × 2 acceleration) and in vivo (2 × 2 acceleration) using a 3D gradient echo acquisition. CONCLUSION: Phase scrambling can be used to perform parallel imaging acceleration without acquisition of separate coil calibration data, demonstrated here for a 3D-Cartesian trajectory. Further research is required to prove the applicability to other 2D and 3D sampling schemes. Magn Reson Med, 2014. © 2014 Wiley Periodicals, Inc.
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Summary Mood disorders are among the most prevalent, psychosocial^ debilitating, chronic and relapsing forms of psychiatric illnesses. Despite considerable advances in their characterization, the heterogeneous nature of susceptibility factors and patient's symptoms could account for the lack of totally effective and remissive treatment. The neurobiological hypothesis of mood disorders etiology has evolved since the monoamine and neurotrophin theories and current evidence is pointing toward their integration in a broader polygenic epistatic model resulting in defective neuroplasticity of circuitries involved in emotion processing. Consequently, the unraveling of molecular underpinning pathways involved in neuronal plasticity, commonly altered among mood disorder syndromes and symptoms, should shed light on their etiology and provide new drug target. The transcription factor CREB has been critically involved in the long-lasting forms of neuronal plasticity and in the regulation of several mood disorders susceptibility genes. In addition, altered CREB activity has been associated with mood disorders pathophysiology and pharmacotherapy. Interestingly, the newly-identified protein CREB-regulated transcription coactivator 1 (CRTC1) was shown by previous studies in the laboratory to be a neuroactivity- dependent cAMP and calcium sensor, a potent activator of CREB-dependent transcription and involved in neuroplasticity mechanisms associated with long-term synaptic potentiation. Furthermore, the major mood disorder susceptibility gene Bdnf was suggested to be transcriptional regulated by CRTC1. Therefore, we aimed to investigate a role for CRTC1 in mood disorders by generating and characterizing a Crtcl deficient mouse model at the behavioral and molecular levels. Interestingly, their comprehensive characterization revealed a behavioral profile mirroring several major symptoms comorbid in mood disorders, including altered social interactions, aggressive behaviors, obesity, psychomotor retardation, increased emotional response to stress, decreased sexual drive and depression-like behaviors. To investigate the molecular mechanisms underlying these pathological behaviors and the implication of CRTC1 in the regulation of CREB-regulated genes in vivo, we also quantified transcript levels of several relevant CREB-regulated susceptibility genes in brain structures involved in the pathophysiology of mood disorders. Strikingly, we found the underexpression of primary components of the neurotrophin system: Bdnf and its cognate receptor TrkB, a marked decrease in the Nr4a family of transcription factors, implicated in neuroplasticity and associated with dopamine-related disorders, as well as in several other relevant CREB regulated genes. Moreover, neurochemical analysis revealed that Crtcl null mice presented alteration in prefrontal cortical monoamine turnover as well as in hippocampal and accumbal serotonin levels, similarly associated with mood disorders etiology and pharmacotherapy. Together, the present thesis supports the involvement of CRTC1 pathway hypofunction in the pathogenesis of mood disorders and specifically in pathological aggression, obesity and depression-related behavior comorbidities. Ultimately, CRTC1 may represent an interesting antidepressant, antiaggressive or mood stabilizer drug target candidate through the modulation of major CREB regulated susceptibility genes. Les troubles de l'humeur comptent parmi les maladies psychiatriques les plus prévalentes, psychosocialement débilitantes, chroniques et avec le plus grand risque de rechute. Malgré de considérable avancées dans leur caractérisation, la nature hétérogène des facteurs de susceptibilité et des symptômes présentés par les patients, semble justifier l'absence de traitement entraînant une rémission complète de la maladie. L'hypothèse de l'étiologie neurobiologique des troubles de l'humeur a évolué depuis la théorie des monoamines et des neurotrophines. Actuellement, elle tend à les englober dans un modèle polygénique épistatique induisant une déficience de la neuroplasticité des circuits impliqué dans la régulation des émotions. Par conséquent, il apparaît particulièrement relevant de caractériser des voies moléculaires impliquées dans la plasticité neuronale, communément altérées parmi les différents syndromes et symptômes des maladies de l'humeur, afin d'améliorer leur compréhension ainsi que de proposer de nouvelles cibles thérapeutiques potentielles. Le facteur de transcription CREB a été de façon répétée et cohérente impliqué dans les mécanismes à long terme de la plasticité neuronale, ainsi que dans la régulation de plusieurs gènes de susceptibilité aux maladies de l'humeur. De plus, une altération dans l'activité de CREB a été impliqué dans leur étiologie et pharmacothérapie. De façon intéressante, des résultats préliminaires sur la protéine récemment découverte CREB-regulated transcription coactivator 1 (CRTC1) ont indiqué que son activation était dépendante de l'activité neuronale, qu'il était un senseur du calcium et de l'AMPc, ainsi qu'un coactivateur de CREB requis et puissant impliqué dans les mécanismes de plasticité neuronale associés à la potentialisation à long terme. En outre, des résultats ont suggéré que le gène majeur de susceptibilité Bdnf est régulé par CRTC1. Ainsi, notre objectif a été d'investiguer un rôle éventuel de CRTC1 dans les maladies de l'humeur en générant et caractérisant une lignée de souris déficiente pour Crtcl, tant au niveau comportemental que moléculaire. De façon intéressante, leur caractérisation détaillée a révélé un profil comportemental reflétant de nombreux aspects des maladies de l'humeur incluant une altération des interactions sociales, une agression pathologique, l'obésité, un retard psychomoteur, une réponse émotionnelle au stress accrue, une diminution de la motivation sexuelle, et des comportements reliés à la dépression. Afin d'investiguer les mécanismes moléculaires sous- jacents cette altération du comportement, ainsi que l'implication de CRTC1 dans l'expression des gènes régulés par CREB in vivo, nous avons quantifié les niveaux de transcrits de plusieurs gènes de susceptibilité régulés par CREB et impliqués dans la physiopathologie des maladies de l'humeur. Remarquablement, nous avons trouvé la sous-expression de composants primordiaux du système neurotrophique: Bdnf et son récepteur TrkB, une diminution majeure de la famille des facteurs de transcription Nr4a, impliqués dans la neuroplasticité et associés à des désordres liés à la dopamine, ainsi que de nombreux autres gènes relevants régulés par CREB. De plus, une analyse neurochimique a révélé que les souris déficientes pour Crtcî présentent une altération du turn-over des monoamines du cortex préfrontal ainsi que des niveaux hippocampaux et accumbaux de sérotonine, associés de façon similaire dans l'étiologie et la pharmacothérapie des maladies de l'humeur. Vue dans son ensemble, la présente thèse supporte l'implication d'une sous-régulation de la voie de CRTCI dans la pathogenèse des maladies de l'humeur ainsi que dans la comorbidité de l'agression pathologique, l'obésité et la dépression. En conclusion, CRTCI pourrait représenter une cible médicamenteuse intéressante aux propriétés antidépressante, antiagressive ou stabilisatrice de l'humeur au travers de la modulation de gènes de susceptibilité majeurs régulés par CREB.
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PURPOSE: The effects of β(2)-agonists on human skeletal muscle contractile properties, particularly on slow fibers, are unclear. Moreover, it remains to be ascertained whether central motor drive (CMD) during voluntary contractions could counter for eventual contractile alterations induced by β(2)-agonists. This study investigated central and peripheral neuromuscular adjustments induced by β(2)-agonist terbutaline on a predominantly slow human muscle, the soleus. METHODS: Ten recreationally active men ingested either a single dose of 8 mg of terbutaline or placebo in a randomized double-blind order (two experimental sessions). Isometric plantarflexion torque was measured during single and tetanic (10 and 100 Hz) stimulations as well as during submaximal and maximal voluntary contractions (MVC). Twitch peak torque and half-relaxation time were calculated. CMD was estimated via soleus electromyographic recordings obtained during voluntary contractions performed at approximately 50% MVC. RESULTS: MVC and twitch peak torque were not modified by terbutaline. Twitch half-relaxation time was 28% shorter after terbutaline administration compared with placebo (P < 0.001). Tetanic torques at 10 and 100 Hz were significantly lower after terbutaline intake compared with placebo (-40% and -24% respectively, P < 0.001). Despite comparable torque of submaximal voluntary contractions in the two conditions, CMD was 7% higher after terbutaline ingestion compared with placebo (P < 0.01). CONCLUSION: These results provide evidence that terbutaline modulates the contractility of the slow soleus muscle and suggest that the increased CMD during submaximal contractions may be viewed as a compensatory adjustment of the central nervous system to counter the weakening action induced by terbutaline on the contractile function of slow muscle fibers.
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In many areas of economics there is a growing interest in how expertise andpreferences drive individual and group decision making under uncertainty. Increasingly, we wish to estimate such models to quantify which of these drive decisionmaking. In this paper we propose a new channel through which we can empirically identify expertise and preference parameters by using variation in decisionsover heterogeneous priors. Relative to existing estimation approaches, our \Prior-Based Identification" extends the possible environments which can be estimated,and also substantially improves the accuracy and precision of estimates in thoseenvironments which can be estimated using existing methods.
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Transposable elements, as major components of most eukaryotic organisms' genomes, define their structural organization and plasticity. They supply host genomes with functional elements, for example, binding sites of the pleiotropic master transcription factor p53 were identified in LINE1, Alu and LTR repeats in the human genome. Similarly, in this report we reveal the role of zebrafish (Danio rerio) EnSpmN6_DR non-autonomous DNA transposon in shaping the repertoire of the p53 target genes. The multiple copies of EnSpmN6_DR and their embedded p53 responsive elements drive in several instances p53-dependent transcriptional modulation of the adjacent gene, whose human orthologs were frequently previously annotated as p53 targets. These transposons define predominantly a set of target genes whose human orthologs contribute to neuronal morphogenesis, axonogenesis, synaptic transmission and the regulation of programmed cell death. Consistent with these biological functions the orthologs of the EnSpmN6_DR-colonized loci are enriched for genes expressed in the amygdala, the hippocampus and the brain cortex. Our data pinpoint a remarkable example of convergent evolution: the exaptation of lineage-specific transposons to shape p53-regulated neuronal morphogenesis-related pathways in both a hominid and a teleost fish.
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The aim of this essay is to deal with economic voting in contexts ofmultilevel governance and to be a contribution to the debate on attribution of responsibilities in popularity functions literature. We use aggregate and individual data from Catalonia in order to analyse the relation between the state of the economy and the support for a sub-state government. The empirical analysis shows that the responsibility hypothesis works in regional governments without explicit macroeconomic competencies. We have also considered the evaluations of government performance on certain specific policies in order to clarify and determine the factors that drive Catalan government support. The article considers the implications of the findings for future attempts to model party support in a context of the European Union.
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The ability of tumor cells to leave a primary tumor, to disseminate through the body, and to ultimately seed new secondary tumors is universally agreed to be the basis for metastasis formation. An accurate description of the cellular and molecular mechanisms that underlie this multistep process would greatly facilitate the rational development of therapies that effectively allow metastatic disease to be controlled and treated. A number of disparate and sometimes conflicting hypotheses and models have been suggested to explain various aspects of the process, and no single concept explains the mechanism of metastasis in its entirety or encompasses all observations and experimental findings. The exciting progress made in metastasis research in recent years has refined existing ideas, as well as giving rise to new ones. In this review we survey some of the main theories that currently exist in the field, and show that significant convergence is emerging, allowing a synthesis of several models to give a more comprehensive overview of the process of metastasis. As a result we postulate a stromal progression model of metastasis. In this model, progressive modification of the tumor microenvironment is equally as important as genetic and epigenetic changes in tumor cells during primary tumor progression. Mutual regulatory interactions between stroma and tumor cells modify the stemness of the cells that drive tumor growth, in a manner that involves epithelial-mesenchymal and mesenchymal-epithelial-like transitions. Similar interactions need to be recapitulated at secondary sites for metastases to grow. Early disseminating tumor cells can progress at the secondary site in parallel to the primary tumor, both in terms of genetic changes, as well as progressive development of a metastatic stroma. Although this model brings together many ideas in the field, there remain nevertheless a number of major open questions, underscoring the need for further research to fully understand metastasis, and thereby identify new and effective ways of treating metastatic disease.
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Traditional economic wisdom says that free entry in a market will drive profits down to zero. This conclusion is usually drawn under the assumption of perfect information. We assumethat a priori there exists imperfect information about theprofitability of the market, but that potential entrants maylearn the demand curve perfectly at negligible cost byengaging in market research. Even if in equilibrium firmslearn the demand perfectly, profits may be strictly positivebecause of insufficient entry. The mere fact that it will notbecome common knowledge that every entrant has perfectinformation about demand causes this surprising result. Belief means doubt. Knowing means certainty. Introduction to the Kabalah.