997 resultados para Basic hypergeometric functions


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In 1952 F. Riesz and Sz.Nágy published an example of a monotonic continuous function whose derivative is zero almost everywhere, that is to say, a singular function. Besides, the function was strictly increasing. Their example was built as the limit of a sequence of deformations of the identity function. As an easy consequence of the definition, the derivative, when it existed and was finite, was found to be zero. In this paper we revisit the Riesz-N´agy family of functions and we relate it to a system for real numberrepresentation which we call (t, t-1) expansions. With the help of these real number expansions we generalize the family. The singularity of the functions is proved through some metrical properties of the expansions used in their definition which also allows us to give a more precise way of determining when the derivative is 0 or infinity.

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Audit report on the Wireless E911 Emergency Communication Fund of the Iowa Homeland Security and Emergency Management Division of the Iowa Department of Public Defense for the year ended June 30, 2007

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A investigação “Do Jardim-de-infância ao Centro de Actividades de Tempos Livres: Representações das Crianças sobre o Brincar” reconhece as crianças como actores sociais, sujeitos de direitos, entre eles, o direito à participação em assuntos que lhes digam directamente respeito, a assuntos de seu interesse, nomeadamente o direito ao brincar. O brincar é uma actividade lúdica, assim como o jogar, importante no processo de crescimento e desenvolvimento da criança e, nos tempos que correm, a sociedade, de uma forma geral, e particularmente as famílias, preocupam-se muito com o trabalho e colocam as necessidades básicas das crianças em segundo plano ao valorizarem acima de tudo o sucesso e o desempenho das mesmas. Assim, se participar significa “tomar parte em”, reconhece-se a necessidade de ouvir as crianças e o que elas têm a dizer sobre essa actividade lúdica, sobre a forma como organizam o seu dia e o tempo que despendem para brincar e sobre a forma como gostariam de ver os seus dias ocupados. É neste pressuposto, de que é através da acção e da voz das crianças, que é possível a construção de um conhecimento teórico e válido que contribua para uma melhor intervenção educativa com as crianças. Esta investigação, que decorreu numa instituição com várias vertentes, entre elas a vertente da Animação Infantil, enquadra-se no paradigma qualitativo de natureza participativa, e procura interpretar os significados atribuídos pelas crianças, que frequentam o Jardim-deinfância da rede pública e a mesma instituição, na condição de Componente de Apoio à Família, ao brincar, às suas vivências no que concerne à gestão do seu quotidiano, quer no que refere ao tempo que passam no Jardim-de-infância, quer no que passam no Prolongamento de Horário/Actividades de Tempos Livres. Neste trabalho de investigação que decorreu numa instituição situada numa freguesia pertencente ao Distrito de Viana do Castelo e que disponibiliza os serviços de ATL, participaram como protagonistas as crianças da faixa etária entre os três e os seis anos de idade e que frequentam dois contextos: educacional e lúdico. Este trabalho é sustentado por um referencial teórico que engloba o brincar na sociedade actual e a sua importância, a educação pré-escolar e as suas funções, a natureza da componente de apoio à família, a animação sócio-educativa e os contextos de vida das crianças, que permitiram questionar a participação infantil em assuntos de seu interesse. Ainda que este estudo não permita generalizações, reflecte-se sobre a realidade existente, dá voz às crianças e indica aspectos que, de uma forma geral, precisam de mais atenção. Afinal o brincar na infância é um assunto sério…

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I present an optimisation model that links paternal investment, male display and female choice. Although deviced for sticklebacks, it readily applies to other fish with male guarding behaviour. It relies on a few basic assumptions on the ways hatching success depends on paternal investment and clutch size, and male survival on paternal investment and signaling. Paternal investment is here a state-dependent decision, and signal a condition-dependent handicap by which males inform females of how much they are willing to invest. Series of predictions are derived on female and male breeding strategies, including optimal levels of signaling and paternal investment as functions of clutch size, own condition, and residual reproductive value, as well as alternative strategies such as egg kleptoparasitism. Some predictions already have empirical support, for which the present model provides new interpretations. Other might readily be tested, e.g. by simple clutch-size manipulations.

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The amygdala is part of a neural network that contributes to the regulation of emotional behaviors. Rodents, especially rats, are used extensively as model organisms to decipher the functions of specific amygdala nuclei, in particular in relation to fear and emotional learning. Analysis of the role of the nonhuman primate amygdala in these functions has lagged work in the rodent but provides evidence for conservation of basic functions across species. Here we provide quantitative information regarding the morphological characteristics of the main amygdala nuclei in rats and monkeys, including neuron and glial cell numbers, neuronal soma size, and individual nuclei volumes. The volumes of the lateral, basal, and accessory basal nuclei were, respectively, 32, 39, and 39 times larger in monkeys than in rats. In contrast, the central and medial nuclei were only 8 and 4 times larger in monkeys than in rats. The numbers of neurons in the lateral, basal, and accessory basal nuclei were 14, 11, and 16 times greater in monkeys than in rats, whereas the numbers of neurons in the central and medial nuclei were only 2.3 and 1.5 times greater in monkeys than in rats. Neuron density was between 2.4 and 3.7 times lower in monkeys than in rats, whereas glial density was only between 1.1 and 1.7 times lower in monkeys than in rats. We compare our data in rats and monkeys with those previously published in humans and discuss the theoretical and functional implications that derive from our quantitative structural findings.

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The chicken represents the best-characterized animal model for B cell development in the so-called gut-associated lymphoid tissue (GALT) and the molecular processes leading to B cell receptor diversification in this species are well investigated. However, the mechanisms regulating B cell development and homeostasis in GALT species are largely unknown. Here we investigate the role played by the avian homologue of B cell-activating factor of the tumor necrosis factor family (BAFF). Flow cytometric analysis showed that the receptor for chicken B cell-activating factor of the tumor necrosis factor family (chBAFF) is expressed by mature and immature B cells. Unlike murine and human BAFF, chBAFF is primarily produced by B cells both in peripheral lymphoid organs and in the bursa of Fabricius, the chicken's unique primary lymphoid organ. In vitro and in vivo studies revealed that chBAFF is required for mature B cell survival. In addition, in vivo neutralization with a decoy receptor led to a reduction of the size and number of B cell follicles in the bursa, demonstrating that, in contrast to humans and mice, in chickens BAFF is also required for the development of immature B cells. Collectively, we show that chBAFF has phylogenetically conserved functions in mature B cell homeostasis but displays unique and thus far unknown properties in the regulation of B cell development in birds.

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This working paper presents the Basic Indicators for Better Governance in International Sport (BIBGIS) as a tool to assess and measure the state of governance of international sport governing bodies. The working paper is organised as follows. We start by presenting different definitions of governance and some examples of principles of good governance in sport and critique them. We then introduce our approach which is based on a limited number of indicators divided among seven dimensions and apply it to the International Olympic Committee (IOC) and other international sport governing bodies. Although our approach can also be used to benchmark the governance of different sport organisations, we demonstrate that it faces limitations. We conclude with suggested next steps for future BIBGIS developments.

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We propose a model and solution methods, for locating a fixed number ofmultiple-server, congestible common service centers or congestible publicfacilities. Locations are chosen so to minimize consumers congestion (orqueuing) and travel costs, considering that all the demand must be served.Customers choose the facilities to which they travel in order to receiveservice at minimum travel and congestion cost. As a proxy for thiscriterion, total travel and waiting costs are minimized. The travel costis a general function of the origin and destination of the demand, whilethe congestion cost is a general function of the number of customers inqueue at the facilities.

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THESIS ABSTRACT Low-pressure anatexis of basic dykes gave rise to unusual, zebra-like migmatites, in the contact metamorphic aureoles of two layered gabbro-pyroxenite intrusions, PXl and PX2, in the root zone of an ocean island, Fuerteventura Basal Complex (Canary Islands). This thesis focuses on the understanding of processes attributing to the partial melting and formation of these migmatites, characterised by a dense network of closely spaced, millimetre-wide leucocratic segregations with perfectly preserved igneous textures. The presence of fluids are required to decrease the solidus of basic igneous lithologies, to allow partial melting in such aloes-pressure (1-2 kb) environment. An oxygen isotope study was thus carried out on dykes inside and beyond the PX2 aureole, in order to decipher the nature and origin of such fluids. Low or negative δ18O values were obtained for whole rocks and mineral-separates, decreasing towards the contact, with the intrusion itself retaining fairly high values. This trend has been attributed to the advection of meteoric water during magma emplacement, with increasing fluid/rock ratios (higher dyke intensities towards the intrusion acting as fluid-pathways) and higher temperatures promoting increasing exchange during recrystallisation. A comparison of whole rock and mineral major- and trace- element data allowed the redistribution of elements .between different mineral phases and generations, during contact metamorphism and partial melting to be assessed. Certain trace-elements, e.g. Zr, Hf, Y, and REEs, were internally redistributed during contact metamorphic recrystallisation, causing- the enrichment of neocrystallised diopsides compared to relict phenocrysts. This has been assigned to the liberation of trace elements on the breakdown of primary minerals, kaersutite and sphene, on entering the thermal aureole. Major and trace element compositions of minerals in migmatite melanosomes and leucosomes are almost identical, pointing to a syn- or post- solidus reequilibration on cooling of the migmatite terrain. The mineralogical, textural and geochemical evolution of dykes in a contact metamorphic aureole, is recorded around an apophysis of the PX1 intrusion, where there is evidence of incipient partial melting. Hydrothermal mineral pseudomorphs in the outer parts of the aureole are progressively replaced by dry mineral assemblages, with increasingly recrystallised diopside and evidence of partial melting -the extent of which varies from one lithology to another. The appearance of more mafic lithologies towards the intrusion, with lower whole rock SiO2 and mobile element abundances, e.g. Rb, Cs, K, has been explained by the migration and accumulation of feldspathic material into leucosomes outside the samples. A micro-structural study of leucosomes and leucocratic pods, with the aid of high-resolution X-ray computed micro-tomography (HRXµCT), allowing the visualization and quantification of shapes and orientations, was carried out in order to better understand the processes of melt segregation in the PX1 aureole. Leucocratic pods, representing former amygdales, are considered as natural strain ellipsoids. Their short axes are oriented perpendicular to leucosome planes, which sub-parallel the intrusive contact. Leucosomes thus effectively represent foliation planes. This implies that the direction of maximum shortening, during migmatisation, was perpendicular to the orientation of leucosomes, contradicting earlier models that suggest leucosomes represent tension veins. RESUME DE LA THESE Un phénomène rare de fusion partielle de filons basiques à basse pression a été étudié dans les auréoles de contact de deux intrusions litées de gabbro-pyroxénite, PX1 et PX2, localisées dans le soubassement de l'île volcanique de Fuerteventura aux Canaries. Cette anatexie a engendré des migmatites finement zébrées d'aspect très inhabituel, dont les processus de formation ont été étudiés dans le présent travail. Ces roches sont caractérisées par un réseau dense de veinules leucocrates d'épaisseur millimétrique, dont les textures ignées sont parfaitement préservées. La fusion partielle de roches basiques à basse pression (1-2 kbar) requiert la présence d'eau afin d'abaisser le solidus du système à des températures géologiquement réalistes. Une étude comparative des isotopes de l'oxygène a ainsi été menée sur des filons respectivement affectés et non affectés par le métamorphisme de contact, afin de confirmer la présence de ces fluides, de déterminer l'importance de leur interaction avec les roches et leur origine. Des valeurs de δ180 basses ou négatives ont été mesurées sur roche totale et minéraux séparés, décroissantes en direction du contact, alors que l'intrusion elle-même a conservé des valeurs élevées. Ce gradient a été attribué à l'advection d'eau météorique durant la mise en place du magma, les températures les plus élevées favorisant d'autant plus la circulation des fluides et les échanges isotopiques durant la recristallisation des roches. Cette recristallisation engendré une redistribution chimique complète des éléments entre les différentes générations de minéraux résultant du métamorphisme de contact et de l'anatexie, mise en évidence par microanalyse. Certains éléments traces comme Zr, Hf, Y et les REE ont été concentrés dans le diopside néoformé consécutivement à la déstabilisation de minéraux primaires riches en ces éléments comme la kaersutite ou le sphène. Les compositions en éléments majeurs et traces des minéraux des mélanosomes et leucosomes des migmatites sont pratiquement identiques, indiquant une rééquilibration syn- à postsolidus lors du refroidissement de l'auréole de contact. La transformation progressive des filons basiques au niveau de leur minéralogie, textures et composition chimique a pu être observée en détail à l'approche du contact d'une apophyse de l'intrusion PX1. La paragenèse magmatique initiale n'est jamais préservée, les faciès les plus distants du contact étant constitués d'un assemblage pseudomorphique hydrothermal. Ce dernier est progressivement remplacé par des assemblages anhydres incluant du diopside néoformé, puis apparaissent les premiers signes de fusion partielle, dont l'importance varie fortement d'une lithologie à l'autre. L'apparition de faciès plus basiques en direction du contact, avec des teneurs réduites en SiO2 et en éléments incompatibles tels Rb, Cs, K, a été attribuée à l'échappement de leucosomes feldspathiques hors du système. Une étude microstructurale de la distribution spatiale du matériel leucocrate au sein des migmatites par microtomographie X de haute résolution (HRXµCT) a été menée pour mieux comprendre les processus de ségrégation des liquides dans l'auréole de PX1. De petites entités ovoïdes, représentant d'anciennes structures amygdalaires au sein des filons, ont été considérées comme des ellipsoïdes marqueurs de la déformation finie. Leur petit axe est orienté perpendiculairement aux plans définis par les leucosomes, eux-mêmes subparallèles au contact intrusif. Les leucosomes matérialisent donc des plans de clivage. Ainsi, la direction de raccourcissement maximum durant la fusion partielle était perpendiculaire à l'orientation des leucosomes, contrairement à ce qui a été dit dans de précédentes publications, qui suggéraient que les leucosomes représentaient des veines de tension. RESUME DE LA THESE (POUR LE GRAND PUBLIC) L'observation directe du soubassement d'une île volcanique est une occasion rare, accessible dans le «complexe de base » de l'île canarienne de Fuerteventura. Ce dernier a enregistré divers phénomènes magmatiques, métamorphiques et de fusion partielle induits par l'intrusion répétée de magmas alimentant des appareils volcaniques sus jacents, sous forme de petits plutons, essaims de filons et complexes annulaires de gabbros alcalins, pyroxénites, syénites et carbonatites. Dans ce contexte de flux de chaleur élevé, des filons basiques ont subi une fusion partielle au contact de deux intrusions de gabbro-pyroxénite, un phénomène extrêmement rare à une profondeur aussi réduite, estimée à quelque 3-6 km. Les produits de cette fusion partielle sont des liquides très riches en feldspath, concentrés en un réseau dense de veinules blanches (leucosomes) au sein du matériau résiduel sombre non fondu (mélanosome) pour former ce qu'on appelle des migmatites. Outre les aspects pétrologiques liés à la formation de ces migmatites, l'intérêt majeur du phénomène réside dans le fait qu'il puisse représenter la source des magmas évolués parfois observés sur les îles océaniques. A des pressions aussi faibles que dans le soubassement de Fuerteventura (1-2 Kbar), la présence de fluides abondants est nécessaire pour abaisser la température de début de fusion des roches (solidus) à des valeurs géologiquement réalistes. Des expériences ont montré que même en présence de plusieurs %-poids d'eau, une température de 1000°C était encore nécessaire pour obtenir une proportion de liquide équivalente à celle observée sur le terrain, soit 25%. Or les magmas alcalins des îles océaniques, bien qu'hydratés, n'en contiennent de loin pas autant, ce qui implique une source d'eau externe. Une étude isotopique de l'oxygène a été entreprise afin de tester cette hypothèse. Les valeurs obtenues en 5180 sont basses ou négatives et indiquent l'influence d'eau d'origine météorique. Cette eau de pluie se serait infiltrée le long des filons depuis la surface du volcan et les aurait complètement hydrothermalisés en profondeur (situation encore visible à l'extérieur de l'auréole de contact), leur permettant ainsi de stocker l'eau nécessaire à leur fusion partielle ultérieure. L'interaction entre eau de pluie et filons a été d'autant plus importante que ces derniers étaient proches du contact avec l'intrusion, ce qui suggère que la circulation de ces eaux et leur interaction avec les roches a été favorisée par la chaleur fournie par l'intrusion elle-même. Un autre aspect de ce travail s'est focalisé sur la redistribution des éléments traces au sein des minéraux des filons basiques durant le métamorphisme de contact et la fusion partielle. Ainsi, le pyroxène de seconde génération est-il sensiblement enrichi en traces telles Zr, Hf, Y et les terres rares, par rapport au pyroxène magmatique originel, en relation avec la déstabilisation de minéraux primaires riches en ces éléments tels le sphène et la kaersutite. Cependant, les compositions en éléments majeurs et traces des minéraux recristallisés des migmatites sont pratiquement les mêmes dans les leucosomes et les mélanosomes, suggérant une rééquilibration chimique complète durant le refroidissement de ces lithologies. Si certaines migmatites se sont comportées en système chimiquement fermé (hormis l'eau météorique), d'autres filons ont manifestement perdu une partie de leurs leucosomes, ainsi qu'en témoigne leur composition progressivement appauvrie en silice et autres éléments incompatibles mobiles, tels K et Rb à l'approche du contact de l'intrusion. Parallèlement à cette évolution chimique, les paragenèses hydrothermales distantes du contact sont progressivement remplacées par des paragenèses anhydres, puis par l'apparition des premiers leucosomes, tandis que les textures magmatiques initiales sont complètement effacées au profit d'une combinaison de textures magmatique dans les leucosomes et en mosaïque dans les mélanosomes. Enfin, la distribution spatiale des liquides de fusion partielle a été étudiée par microtomographie X de haute résolution, dans des filons contenant des entités ovoïdes leucocrates, sans doute d'anciennes amygdales à zéolites. Ces dernières ont été considérées comme des ellipsoïdes de la déformation finie. L'orientation de leur petit axe, perpendiculaire au plan défini par les veinules de leucosomes, indique que ces derniers représentent des plans de clivage perpendiculaires à la direction de raccourcissement maximum. Ainsi, la ségrégation des liquides de fusion partielle se serait faite dans les plans de compression et non dans des plans de dilatation, contrairement à ce que laisserait penser le sens commun.

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This paper proposes an exploration of the methodology of utilityfunctions that distinguishes interpretation from representation. Whilerepresentation univocally assigns numbers to the entities of the domainof utility functions, interpretation relates these entities withempirically observable objects of choice. This allows us to makeexplicit the standard interpretation of utility functions which assumesthat two objects have the same utility if and only if the individual isindifferent among them. We explore the underlying assumptions of suchan hypothesis and propose a non-standard interpretation according towhich objects of choice have a well-defined utility although individualsmay vary in the way they treat these objects in a specific context.We provide examples of such a methodological approach that may explainsome reversal of preferences and suggest possible mathematicalformulations for further research.

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Audit report on the Jackson County Sanitary Disposal Agency for the year ended June 30, 2008

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Treball de recerca realitzat per alumnes d’ensenyament secundari i guardonat amb un Premi CIRIT per fomentar l'esperit científic del Jovent l’any 2010. L’objectiu del treball ha consistit a desenvolupar un programa informàtic per controlar les fases d'un procés de rentat industrial.

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Audit report on the Wireless E911 Emergency Communication Fund of the Iowa Homeland Security and Emergency Management Division of the Iowa Department of Public Defense for the year ended June 30, 2008

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AbstractBackground: Mucosal healing is becoming a major goal in the treatment of Crohn's disease. It has been previously reported that myeloid cells induce mucosal healing in a mouse model of acute colitis. The aim in this study is to investigate the pro-repair function of myeloid cells in healthy donors (HD) and Crohn's disease patients (CD).Methods: Peripheral blood mononuclear cells (PBMC) from HD and CD patients were isolated from blood samples and tested either directly or after differentiation ex-vivo into macrophages (Μφ). Intestinal macrophages (IMACs) were isolated from the bowel mucosa of patients undergoing intestinal surgical resections. Through an in vitro wound healing assay the repairing ability of these various human myeloid cells and the mechanisms responsible of wound healing were evaluated.Results: PBMC and myeloid CD14+ cells from HD and CD were not able to repair at any tested cell concentration. Μφ from HD and ulcerative colitis (UC) patients were able to induce wound healing and this capacity was partially mediated by Hepatocyte Growth Factor (HGF). Remarkably, CD Μφ were unable to promote wound healing and produced lower levels of HGF as compared to Μφ from HD or UC patients. In particular, Μφ from CD in active phase (ACD) exhibited the weakest repair function, but this defect was rescued if rh- GM-CSF was added during the differentiation of PBMCs. Interestingly, IMACs from HD promoted wound healing and produced HGF.Conclusion: We demonstrated that CD Μφ, unlike HD or UC Μφ, were defective in promoting wound healing, in particular if coming from an ACD. This deficient pro-repair function was related to a lower production of HGF. IMACs from HD colonic mucosa induced wound healing, confirming the results obtained with Μφ. Our results are in keeping with the current theory of CD as an innate immunodeficiency. In this context, Μφ may be responsible for the mucosal repair defects observed in CD patients and for the subsequent chronic activation of the adaptive immune response.

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Mutation of the nuclear receptor peroxisome proliferator-activated receptor beta/delta (PPARbeta/delta) severely affects placenta development, leading to embryonic death at embryonic day 9.5 (E9.5) to E10.5 of most, but not all, PPARbeta/delta-null mutant embryos. While very little is known at present about the pathway governed by PPARbeta/delta in the developing placenta, this paper demonstrates that the main alteration of the placenta of PPARbeta/delta-null embryos is found in the giant cell layer. PPARbeta/delta activity is in fact essential for the differentiation of the Rcho-1 cells in giant cells, as shown by the severe inhibition of differentiation once PPARbeta/delta is silenced. Conversely, exposure of Rcho-1 cells to a PPARbeta/delta agonist triggers a massive differentiation via increased expression of 3-phosphoinositide-dependent kinase 1 and integrin-linked kinase and subsequent phosphorylation of Akt. The links between PPARbeta/delta activity in giant cells and its role on Akt activity are further strengthened by the remarkable pattern of phospho-Akt expression in vivo at E9.5, specifically in the nucleus of the giant cells. In addition to this phosphatidylinositol 3-kinase/Akt main pathway, PPARbeta/delta also induced giant cell differentiation via increased expression of I-mfa, an inhibitor of Mash-2 activity. Finally, giant cell differentiation at E9.5 is accompanied by a PPARbeta/delta-dependent accumulation of lipid droplets and an increased expression of the adipose differentiation-related protein (also called adipophilin), which may participate to lipid metabolism and/or steroidogenesis. Altogether, this important role of PPARbeta/delta in placenta development and giant cell differentiation should be considered when contemplating the potency of PPARbeta/delta agonist as therapeutic agents of broad application.