975 resultados para Order-preserving Functions
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There has been much debate regarding the electoral strategy adopted by New Labour in the lead-up to and then during their time in government. This paper addresses the issue from the perspective of left/right and libertarian/authoritarian considerations by examining data on individual attitudes from the British Social Attitudes survey between 1986 and 2009. The analysis indicates that New Labour’s move towards the right on economic and public policy was the main driver towards attracting new centrist voters and could thus be labelled ‘broadly’ populist. The move towards a tougher stance on law and order was more ‘narrowly’ populist in that it was used more to minimise the reduction in support from Labour’s traditional base on the left than to attract new votes.
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Based on third order linear sequences, an improvement version of the Diffie-Hellman distribution key scheme and the ElGamal public key cryptosystem scheme are proposed, together with an implementation and computational cost. The security relies on the difficulty of factoring an RSA integer and on the difficulty of computing the discrete logarithm.
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We present an envelope theorem for establishing first-order conditions in decision problems involving continuous and discrete choices. Our theorem accommodates general dynamic programming problems, even with unbounded marginal utilities. And, unlike classical envelope theorems that focus only on differentiating value functions, we accommodate other endogenous functions such as default probabilities and interest rates. Our main technical ingredient is how we establish the differentiability of a function at a point: we sandwich the function between two differentiable functions from above and below. Our theory is widely applicable. In unsecured credit models, neither interest rates nor continuation values are globally differentiable. Nevertheless, we establish an Euler equation involving marginal prices and values. In adjustment cost models, we show that first-order conditions apply universally, even if optimal policies are not (S,s). Finally, we incorporate indivisible choices into a classic dynamic insurance analysis.
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This paper presents an axiomatic characterization of difference-form group contests, that is, contests fought among groups and where their probability of victory depends on the difference of their effective efforts. This axiomatization rests on the property of Equalizing Consistency, stating that the difference between winning probabilities in the grand contest and in the smaller contest should be identical across all participants in the smaller contest. This property overcomes some of the drawbacks of the widely-used ratio-form contest success functions. Our characterization shows that the criticisms commonly-held against difference-form contests success functions, such as lack of scale invariance and zero elasticity of augmentation, are unfounded.By clarifying the properties of this family of contest success functions, this axiomatization can help researchers to find the functional form better suited to their application of interest.
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I model the link between political regime and level of diversification following a windfall of natural resource revenues. The explanatory variables I make use of are the political support functions embedded within each type of regime and the disparate levels of discretion, openness, transparency, and accountability of government. I show that a democratic government seeks to maximize the long-term consumption path of the representative consumer, in order to maximize its chances of re-election, while an authoritarian government, in the absence of any electoral mechanism of accountability, seeks to buy off and entrench a group of special interests loyal to the government and potent enough to ensure its short-term survival. Essentially the contrast in the approaches towards resource rent distribution comes down to a variation in political weights on aggregate welfare and rentierist special interests endogenized by distinct political support functions.
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BACKGROUND: We previously reported that myeloid cells can induce mucosal healing in a mouse model of acute colitis. Promotion of mucosal repair is becoming a major goal in the treatment of Crohn's disease. Our aim in this study is to investigate the pro-repair function of myeloid cells in healthy donor (HD) and Crohn's disease patients (CD). METHODS: Peripheral blood mononuclear cells (PBMC) from HD and CD patients were isolated from blood samples by Ficoll density gradient. Monocytic CD14+ cells were positively selected by Macs procedure and then differentiated ex-vivo into macrophages (Mφ). The repair function of PBMC, CD14+ monocytic cells and macrophages were evaluated in an in vitro wound healing assay. RESULTS: PBMC and CD14+ myeloid cells from HD and CD were not able to repair at any tested cell concentration. Remarkably, HD Mφ were able to induce wound healing only at high concentration (105 added Mφ), but, if activated with heat killed bacteria, they were able to repair even at very low concentration. On the contrary, not activated CD Mφ were not able to promote healing at any rate, but this function was restored upon activation. CONCLUSION: We showed that CD Mφ in their steady state, unlike HD Mφ, are defective in promoting wound healing. Our results are in keeping with the current theory of CD as an innate immunodeficiency. Defective Mφ may be responsible to the mucosal repair defects in CD patients and to the subsequent chronic activation of the adaptive immune response.
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Carotenoid-based yellowish to red plumage colors are widespread visual signals used in sexual and social communication. To understand their ultimate signaling functions, it is important to identify the proximate mechanism promoting variation in coloration. Carotenoid-based colors combine structural and pigmentary components, but the importance of the contribution of structural components to variation in pigment-based colors (i.e., carotenoid-based colors) has been undervalued. In a field experiment with great tits (Parus major), we combined a brood size manipulation with a simultaneous carotenoid supplementation in order to disentangle the effects of carotenoid availability and early growth condition on different components of the yellow breast feathers. By defining independent measures of feather carotenoid content (absolute carotenoid chroma) and background structure (background reflectance), we demonstrate that environmental factors experienced during the nestling period, namely, early growth conditions and carotenoid availability, contribute independently to variation in yellow plumage coloration. While early growth conditions affected the background reflectance of the plumage, the availability of carotenoids affected the absolute carotenoid chroma, the peak of maximum ultraviolet reflectance, and the overall shape, that is, chromatic information of the reflectance curves. These findings demonstrate that environment-induced variation in background structure contributes significantly to intraspecific variation in yellow carotenoid-based plumage coloration.
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La finalitat d'aquest projecte és aconseguir construir codis binaris perfectes no lineals de manera eficient. Per a fer-ho, hem desenvolupat un paquet de software per a l'intèrpret MAGMA que conté funcions per a la construcció de codis perfectes, càlcul d'invariants de codis i altres funcions complementàries per a fer càlculs sobre les paraules d'un codi.
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The orexigenic neurotransmitter neuropeptide Y (NPY) plays a central role in the hypothalamic control of food intake and energy balance. NPY also exerts an inhibition of the gonadotrope axis that could be important in the response to poor metabolic conditions. In contrast, leptin provides an anorexigenic signal to centrally control the body needs in energy. Moreover, leptin contributes to preserve adequate reproductive functions by stimulating the activity of the gonadotrope axis. It is of interest that hypothalamic NPY represents a primary target of leptin actions. To evaluate the importance of the NPY Y1 and Y5 receptors in the downstream pathways modulated by leptin and controlling energy metabolism as well as the activity of the gonadotrope axis, we studied the effects of leptin administration on food intake and reproductive functions in mice deficient for the expression of either the Y1 or the Y5 receptor. Furthermore, the role of the Y1 receptor in leptin resistance was determined in leptin-deficient ob/ob mice bearing a null mutation in the NPY Y1 locus. Results point to a crucial role for the NPY Y1 receptor in mediating the NPY pathways situated downstream of leptin actions and controlling food intake, the onset of puberty, and the maintenance of reproductive functions.
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Activation of the transcription factor nuclear factor (NF)-kappaB is essential for the normal functioning of the immune system. Deregulated NF-kappaB signalling in lymphocytes can lead to immunodeficiency, but also to autoimmunity or lymphomas. Many of the signalling components controlling NF-kappaB activation in lymphocytes are now known, but it is less clear how distinct molecular components of this pathway are regulated. Here, we summarize recent findings on post-translational modifications of intracellular components of this pathway. Phosphorylation of the CARMA1 and BCL10 proteins and ubiquitylation of BCL10 affect the formation and stability of the CARMA1-BCL10-MALT1 (CBM) complex, and also control negative feedback regulation of the NF-kappaB signalling pathway. Moreover, the study of BCL10 phosphorylation isoforms has revealed a new mechanism controlling BCL10 nuclear translocation and an unexpected role for BCL10 in the regulation of the actin cytoskeleton.
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Treball de recerca realitzat per un alumne d'ensenyament secundari i guardonat amb un Premi CIRIT per fomentar l'esperit científic del Jovent l'any 2009. Aquest treball de recerca és un projecte sobre el disseny i la creació d’un programa informàtic de codi obert amb l’objectiu de mesurar acceleracions en tres dimensions utilitzant el comandament de la wii, també conegut com a wiimote. Per tant, s'ha creat un programa que es connecta amb el wiimote, en rep les dades, les guarda i les representa per analitzar posteriorment diversos tipus de moviments i les seves acceleracions. Per tal de fer això es va aprofitar una biblioteca de funcions de codi obert ja existent que aporta les funcions principals per a la comunicació i control del comandament. El codi obert és un concepte que s’utilitza per als projectes informàtics, el codi dels quals està a la disposició de qui el necessiti. La biblioteca utilitzada està escrita en llenguatge C i per a plataforma Linux, i per tal d’aprofitar-la es va haver d’aprendre a utilitzar tant el llenguatge com la plataforma ja que no s'hi havia treballat mai abans. Gràcies a aquest projecte s'ha tingut la possibilitat de veure el funcionament d’algunes tecnologies alternatives i veure’n els avantatges sobre les convencionals o propietàries. Així doncs, des del punt de vista de l'autor, ha estat útil i enriquidor el fet de realitzar-lo.
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Treball de recerca realitzat per un alumne d'ensenyament secundari i guardonat amb un Premi CIRIT per fomentar l'esperit científic del Jovent l'any 2009. Aquest treball tracta sobre el temps de garantia o de vida útil d’un producte alimentari i està basat en esbrinar quin és el millor mètode o envàs per conservar el pernil cuit llescat durant la seva vida útil, per tal que es mantinguin les propietats organolèptiques i microbiològiques inicials de l’aliment durant el màxim de temps possible. Per comparar envasos he utilitzat els industrials (envàs al buit i envàs en atmosfera) i els envasos que podem trobar quan comprem un producte llescat en el mostrador d’una botiga o supermercat. Per a fer l’estudi doncs s’ha utilitzat el pernil cuit, conegut com a pernil dolç, un dels productes més consumits per la societat actual. El pernil ha estat tractat en tres situacions diferents: llescat en una màquina de carnisseria i envasat en mètodes de conservació domèstics, llescat en màquines industrials i envasat en diferents envasos (al buit i en atmosfera modificada) utilitzats per les grans empreses i llescat en màquines industrials i envasat al buit sotmès a un tractament amb altes pressions. Després d’aquests processos s’ha realitzat un estudi de vida útil, és a dir, s’ha analitzat el producte al laboratori, amb l’objectiu de trobar quin és el millor envàs per a la conservació del pernil cuit.
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Aquest projecte presenta el disseny, construcció i programació d’un robot autònom, com a base per una proposta educativa. Per aconseguir aquest objectiu s’ha dotat el robot d’una unitat de procés, un sistema de locomoció i un seguit de sensors que proporcionaran a la unitat informació respecte l’entorn. Per gestionar totes aquestes funcionalitats, s’ha fet servir un sistema operatiu en temps real capaç de gestionar amb efectivitat les tasques que puguin ser executades pel robot. Finalment, s’ha exposat una detallada descripció dels costos per una producció de volum mig i de caire merament educatiu.
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"Vegeu el resum a l'inici del document del fitxer adjunt."
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The dual function of eosinophils is clearly illustred in schistosomiasis. Well equipped in membrane receptors for immunoglobulins and complement, and due to the presence of granule basic proteins, eosinophils can become cytotoxic for parasite larvae and thus participate to protective immunity. However mediators can also exert their cytolytic effect on normal cells or tissues, inducing therefore pathology. Through ADCC mechanisms against schistosome larvae in vitro involving different antibody isotypes (IgG, IgE and IgA) and also in experiments performed in vivo, eosinophils have been clearly involved in protective immunity. Although no direct evidence of the protective role of eosinophils were brought in humans, the striking association of eosinophil-dependent cytotoxic antibody isotypes with resistance to reinfection (for instance IgE and IgA antibodies), whereas in vitro blocking antibody isotypes (IgG4, IgM) were detected in susceptible subjects, strongly, suggested the participation of eosinophils in antibody-dependent protective immune response. However eosinophils could also participate to granuloma formation around S. mansoni eggs and consequently to the pathological reactions induced by schistosomiasis.