59 research outputs found

    Charge and spin polarized currents in mesoscopic rings with Rashba spin-orbit interactions coupled to an electron reservoir

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    The electronic states of a mesoscopic ring are assessed in the presence of Rashba Spin Orbit coupling and a U(1)U(1) gauge field. Spin symmetric coupling to an ideal lead is implemented following B\"uttiker's voltage probe. The exact density of states is derived using the reservoir uncoupled eigenstates as basis functions mixed by the reservoir coupling. The decay time of uncoupled electron eigenstates is derived by fitting the broadening profiles. The spin and charge persistent currents are computed in the presence of the SO interaction and the reservoir coupling for two distinct scenarios of the electron filling fraction. The degradation of the persistent currents depends uniformly on the reservoir coupling but nonuniformly in temperature, the latter due to the fact that currents emerge from different depths of the Fermi sea, and thus for some regimes of flux, they are provided with a protective gap. Such flux regimes can be tailored by the SO coupling for both charge and spin currents

    Fast and accurate methods to unveil the mechanisms of contrast formation in High Resolution Force Microscopy

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    Tesis Doctoral inédita leída en la Universidad Autónoma de Madrid, Facultad de Ciencias, Departamento de Física Teórica de la Materia Condensada. Fecha de lectura: 15-06-201

    Nutzung von Resistenzmechanismen verschiedener Rebarten als Alternative zum Einsatz von Kupfer im Ă–koweinbau

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    Extrakte aus Wildreben bzw. Hybriden mit hoher Resistenz: Es war zu prüfen, ob durch die Applikation von Blattextrakten von Nicht-Vitis-vinifera-Rebsorten auf Qualitätsrebsorten Plasmopara viticola und andere Pathogene bekämpft, unterdrückt oder pflanzeneigene Abwehrmechanismen bei Qualitätsrebsorten durch in den Extrakten enthaltene Elicitoren aktiviert werden können resp. ob mit den Pflanzenextrakten eine direkte Bekämpfung dieser Problemschaderreger möglich ist. Kupferreduktionspotential bei Anbau neuer Vitis vinifera PIWI - Sorten: Der Anbau von PIWI’s ermöglicht einen weitgehenden Verzicht auf Pflanzenschutz und ist ökologisch und ökonomisch die nachhaltigste Form des Weinbaus überhaupt. Das Kupfereinsparungspotential durch den Anbau von PIWI’s ist vermutlich abhängig von der Resistenz der Sorte und von den klimatischen Bedingungen am Standort. Das für die jeweilige Sorte notwendige Maß an Pflanzenschutz soll in diesem Projekt erstmals ermittelt werden. Daraus lässt sich ein durchschnittliches Einsparpotential an Kupfer bestimmen. Orientierungsversuche mit geringen Stockzahlen im Freiland an Zuchtstämmen mit bereits pyramidisierten Plasmopara Resistenzen wurden in einer 2009 erstellten Prüfanlage mit Überkronenberegnung durchgeführt, in der beliebig hohe Befallsbedingungen für die Rebenperonospora geschaffen werden können

    Clinical Research and Development of Tuberculosis Diagnostics: Moving From Silos to Synergy

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    The development, evaluation, and implementation of new and improved diagnostics have been identified as critical needs by human immunodeficiency virus (HIV) and tuberculosis researchers and clinicians alike. These needs exist in international and domestic settings and in adult and pediatric populations. Experts in tuberculosis and HIV care, researchers, healthcare providers, public health experts, and industry representatives, as well as representatives of pertinent US federal agencies (Centers for Disease Control and Prevention, Food and Drug Administration, National Institutes of Health, United States Agency for International Development) assembled at a workshop proposed by the Diagnostics Working Group of the Federal Tuberculosis Taskforce to review the state of tuberculosis diagnostics development in adult and pediatric populations

    Populist Mobilization: A New Theoretical Approach to Populism*

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    Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/112280/1/j.1467-9558.2011.01388.x.pd

    Mate choice for genetic quality when environments vary: suggestions for empirical progress

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    Mate choice for good-genes remains one of the most controversial evolutionary processes ever proposed. This is partly because strong directional choice should theoretically deplete the genetic variation that explains the evolution of this type of female mating preferences (the so-called lek paradox). Moreover, good-genes benefits are generally assumed to be too small to outweigh opposing direct selection on females. Here, we review recent progress in the study of mate choice for genetic quality, focussing particularly on the potential for genotype by environment interactions (GEIs) to rescue additive genetic variation for quality, and thereby resolve the lek paradox. We raise five questions that we think will stimulate empirical progress in this field, and suggest directions for research in each area: 1) How is condition-dependence affected by environmental variation? 2) How important are GEIs for maintaining additive genetic variance in condition? 3) How much do GEIs reduce the signalling value of male condition? 4) How does GEI affect the multivariate version of the lek paradox? 5) Have mating biases for high-condition males evolved because of indirect benefits

    Modeling Planarian Regeneration: A Primer for Reverse-Engineering the Worm

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    A mechanistic understanding of robust self-assembly and repair capabilities of complex systems would have enormous implications for basic evolutionary developmental biology as well as for transformative applications in regenerative biomedicine and the engineering of highly fault-tolerant cybernetic systems. Molecular biologists are working to identify the pathways underlying the remarkable regenerative abilities of model species that perfectly regenerate limbs, brains, and other complex body parts. However, a profound disconnect remains between the deluge of high-resolution genetic and protein data on pathways required for regeneration, and the desired spatial, algorithmic models that show how self-monitoring and growth control arise from the synthesis of cellular activities. This barrier to progress in the understanding of morphogenetic controls may be breached by powerful techniques from the computational sciences—using non-traditional modeling approaches to reverse-engineer systems such as planaria: flatworms with a complex bodyplan and nervous system that are able to regenerate any body part after traumatic injury. Currently, the involvement of experts from outside of molecular genetics is hampered by the specialist literature of molecular developmental biology: impactful collaborations across such different fields require that review literature be available that presents the key functional capabilities of important biological model systems while abstracting away from the often irrelevant and confusing details of specific genes and proteins. To facilitate modeling efforts by computer scientists, physicists, engineers, and mathematicians, we present a different kind of review of planarian regeneration. Focusing on the main patterning properties of this system, we review what is known about the signal exchanges that occur during regenerative repair in planaria and the cellular mechanisms that are thought to underlie them. By establishing an engineering-like style for reviews of the molecular developmental biology of biomedically important model systems, significant fresh insights and quantitative computational models will be developed by new collaborations between biology and the information sciences

    Ni crisis ni panaceas: dinámicas y transformaciones de los sistemas partidarios en América Latina

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    A nivel global, tanto en la literatura especializada como en el debate público, la desafección ciudadana hacia la cosa pública, el debilitamiento de los partidos políticos y el aumento de la abstención contribuyeron a asentar la idea de una crisis de los sistemas de partidos y de la democracia. Diferentes indicadores darían cuenta de esta crisis: el desarraigo social de los partidos que consagró el modelo del partido cartel (Katz y Mair 1995); el declive de la militancia (Van Biezen, Mair y Poguntke 2012; Whiteley 2011); la erosión de las estructuras partidarias tradicionales capturadas por el lobby corporativo (Crouch 2004 [2014], 112) o la tecnocracia; la pérdida de capacidad de los líderes para construir partidos programáticos que expresaran identidades políticas duraderas (Cheresky 2006; Dalton 2004; Luna 2014b); o su incapacidad para responder con una mayor deliberación interna a los desafíos de la representación política (Accetti y Wolkenstein 2017).Fil: Alenda, Stéphanie. Universidad Andrés Bello; ChileFil: Varetto, Carlos Augusto. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de San Martin. Escuela de Politica y Gobierno. Centro de Estudios Federales y Electorales; Argentin

    A Distributed Middleware for Automotive Applications

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    Modern cars contain a multitude of micro controllers for a wide area of tasks. The micro controllers are connected to controller networks through different bus systems. The development of a connected and cooperating system is difficult and poorly supported by the existing development tools. With the KESO system we have implemented a very small and adapted Java middleware for an OSEK/VDX operating system that allows the safe coexistence of tasks on a single micro controller by providing software-based memory protection. In this paper we present our approach on extending KESO to a distributed multi-JVM that provides an integrated view on controller networks. KESO will provide one communication mechanism that transparently allows the communication between different tasks on the same as well as tasks on different micro controllers over different communication systems
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