872 research outputs found

    The Best-or-Worst and the Postdoc problems

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    We consider two variants of the secretary problem, the\emph{ Best-or-Worst} and the \emph{Postdoc} problems, which are closely related. First, we prove that both variants, in their standard form with binary payoff 1 or 0, share the same optimal stopping rule. We also consider additional cost/perquisites depending on the number of interviewed candidates. In these situations the optimal strategies are very different. Finally, we also focus on the Best-or-Worst variant with different payments depending on whether the selected candidate is the best or the worst

    U-Pb zircon dating of the Gruf Complex: disclosing the late Variscan granulitic lower crust of Europe stranded in the Central Alps

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    Permian granulites associated with noritic intrusions and websterites are a common feature of the post-Variscan European crust. Such granulites are common in the Southern Alps (e.g. Ivrea Zone), but occur only in the Gruf Complex in the Central Alps. To understand the geotectonic significance of these granulites, in particular in the context of Alpine migmatisation, zircons from 15 high-grade samples have been U-Pb dated by SHRIMP II analysis. Oscillatory zoned zircons from charnockite sheets, interpreted as melts generated through granulite facies fluid-absent biotite melting at 920-940°C, yield ages of 282-260Ma. Some of these zircons contain inclusions of opx, unequivocally attributable to the granulite facies, thus confirming a Permian age for the charnockites and associated granulites. Two samples from an enclave-rich orthogneiss sheet yield Cambrian and Ordovician zircon cores. Two deformed leucogranites and six ortho- and augengneisses, which compose two-thirds of the Gruf Complex, give zircon ages of 290-260Ma. Most zircons have milky rims with ages of 34-29Ma. These rims date the Alpine amphibolite facies migmatisation, an interpretation confirmed by directly dating a leucosome pocket from upper amphibolite facies metapelites. The Gruf charnockites associated with metre-scale schlieren and boudins of opx-sapphirine-garnet-granulites, websterites and gabbronorites can thus be identified as part of the post-Variscan European lower crust. A geotectonic reconstruction reveals that this piece of lower crust stranded in the (European) North upon rifting of the Neotethys, such contrasting the widespread granulite units in the Southern Alps. Emplacement of the Gruf lower crust into its present-day position occurred during migmatisation and formation of the Bergell Pluton in the aftermath of the breakoff of the European sla

    Plan de acción frente al consumismo global de la Nueva Economía: Revelaciones sobre economía, empresa y consumo del s. XXI

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    Este estudio crítico y revisionista, de corte interdisciplinario (entre Humanidades y Ciencias Sociales), alerta sobre los peligros de avanzar hacia una sociedad masa global de consumo, donde se acentúe la deshumanización y asocialización, al primarse el tener al ser (el bienestar a la felicidad, el negocio al ocio, la empresa al oficio, la pulsión a la experiencia, etc.). Se ofrece así un plan de acción que va de lo más general (retirando los velos de confusión que impiden reconocer el mundo posglobalizado y estudiarlo tal como es), pasando a centrar la atención en las complejas reglas económicas y empresariales del nuevo milenio, para terminar evaluando los riesgos de la inautenticidad del actual consumidor.This is a critical and reviewer study, under an interdisciplinary approach (between Liberal Arts and Social Sciences), which warns to move on a global mass consumer society and its dangers, by the accentuated lost of humanity and sociality, because the priority of the having-issue than the been-issue (the preference of welfare than happiness, the business than the recreation, the company than the profession, the desire than the experience, etc.). The structure of the paper goes from general view (removing the confusion veils that make impossible the recognition of the post-globalized World and its study), to particular view (focusing on the complex economic and business rules in the new millennium), and the risk evaluation of the non-authenticity of the current consumer

    Transgenerational latent early-life associated regulation unites environment and genetics across generations

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    The origin of idiopathic diseases is still poorly understood. The latent early-life associated regulation (LEARn) model unites environmental exposures and gene expression while providing a mechanistic underpinning for later-occurring disorders. We propose that this process can occur across generations via transgenerational LEARn (tLEARn). In tLEARn, each person is a 'unit' accumulating preclinical or subclinical 'hits' as in the original LEARn model. These changes can then be epigenomically passed along to offspring. Transgenerational accumulation of 'hits' determines a sporadic disease state. Few significant transgenerational hits would accompany conception or gestation of most people, but these may suffice to 'prime' someone to respond to later-life hits. Hits need not produce symptoms or microphenotypes to have a transgenerational effect. Testing tLEARn requires longitudinal approaches. A recently proposed longitudinal epigenome/envirome-wide association study would unite genetic sequence, epigenomic markers, environmental exposures, patient personal history taken at multiple time points and family history
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