13 research outputs found

    Unidirectional Quantum Transport in Optically Driven VV-type Quantum Dot Chains

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    We predict a mechanism for achieving complete population inversion in a continuously driven InAs/GaAs semiconductor quantum dot featuring VV-type transitions. This highly nonequilibrium steady state is enabled by the interplay between VV-type interband transitions and a non-Markovian decoherence mechanism, introduced by acoustic phonons. The population trapping mechanism is generalized to a chain of coupled emitters. Exploiting the population inversion, we predict unidirectional excitation transport from one end of the chain to the other without external bias, independent of the unitary interdot coupling mechanism

    Masturbación femenina en mujeres universitarias: diseño e implementación de una aplicación móvil

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    Curso de Especial Interés: Psicología y sexualidadEl trabajo investigativo tuvo como objetivo diseñar e implementar una aplicación móvil que promueva de forma activa la psicoeducación con respecto a la masturbación femenina, el autoconocimiento y reconocimiento corporal. Se aplicaron dos instrumentos y en base a los resultados se construyó una aplicación móvil, la cual posee contenido científico relevante para la sexualidad femenina.Resumen 1. Justificación 2. Marco Teórico 3. Objetivos 4. Estudio de mercadeo 5. Resultados 6. Conclusiones Referencias ApéndicesPregradoPsicólog

    Evaluating the Farming/Language Dispersal Hypothesis with genetic variation exhibited by populations in the Southwest and Mesoamerica

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    The Farming/Language Dispersal Hypothesis posits that prehistoric population expansions, precipitated by the innovation or early adop-tion of agriculture, played an important role in the uneven distribution of language families recorded across the world. In this case, the most widely spread language families today came to be distributed at the expense of those that have more restricted distributions. In the Americas, Uto-Aztecan is one such language family that may have been spread across Mesoamerica and the American Southwest by ancient farmers. We evaluated this hypothesis with a large-scale study of mitochondrial DNA (mtDNA) and Y-chromosomal DNA vari-ation in indigenous populations from these regions. Partial correlation coefficients, determined with Mantel tests, show that Y-chromosome variation in indigenous populations from the American Southwest and Mesoamerica correlates significantly with linguistic distances (r = 0.33–0.384; P < 0.02), whereas mtDNA diversity correlates significantly with only geographic distance (r = 0.619; P = 0.002). The lack of correlation between mtDNA and Y-chromosome diversity is consistent with differing population histories of males and females in these regions. Although unlikely, if groups of Uto-Aztecan speakers were responsible for the northward spread of agriculture and their languages from Mesoamerica to the Southwest, this migration was possibly biased to males. However, a recent in situ population expansion within the American Southwest (2,105 years before present; 99.5% confidence interval = 1,273–3,773 YBP), one that probably followed the introduction and intensification of maize agriculture in the region, may have blurred ancient mtDNA patterns, which might otherwise have revealed a closer genetic relationship between females in the Southwest and Mesoamerica
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