A Switch from Diurnal to Nocturnal Activity in S. ehrenbergi Is Accompanied by an Uncoupling of Light Input and the Circadian Clock

AbstractThe subterranean mole rat Spalax ehrenbergi superspecies represents an extreme example of adaptive visual and neuronal reorganization [1, 2]. Despite its total visual blindness, its daily activity rhythm is entrainable to light-dark cycles [3], indicating that it can confer light information to the clock. Although most individuals are active during the light phase under laboratory conditions (diurnal animals), some individuals switch their activity period to the night (nocturnal animals) [3, 4]. Similar to other rodents [5], the Spalax circadian clock is driven by a set of clock genes, including the period (sPer) genes [6, 7]. In this work, we show that diurnal mole rats express the Per genes sPer1 and sPer2 with a peak during the light period. Light can synchronize sPer gene expression to an altered light-dark cycle and thereby reset the clock. In contrast, nocturnal Spalax express sPer2 in the dark period and sPer1 in a biphasic manner, with a light-dependent maximum during the day and a second light-independent maximum during the night. Although sPer1 expression remains light inducible, this is not sufficient to reset the molecular clockwork. Hence, the strict coupling of light, Per expression, and the circadian clock is lost. This indicates that Spalax can dissociate the light-driven resetting pathway from the central clock oscillator

Habilidades gerenciales como estrategia de competitividad empresarial en las pequeñas y medianas empresas (Pymes)

Esta investigación tiene como objetivo medir la influencia de las habilidades gerenciales como factor interno en la competitividad empresarial que perciben los empresarios de las pequeñas y medianas empresas (Pymes) de Hermosillo, Sonora, México. Para tal efecto, se utilizó una metodología mixta con el fin de poder recolectar, analizar y vincular los datos cuantitativos y cualitativos, y responder al planteamiento de la investigación con mayor evidencia científica. La primera fase fue exploratoria mediante entrevista a panel de expertos usando el método Delphi, para contextualizar la problemática objeto de análisis y validar el instrumento de medida. En la segunda fase se muestrearon 108 Pymes y se realizó un análisis estadístico utilizando modelos de ecuaciones estructurales (PLS) para obtener resultados. Las conclusiones demostraron que las habilidades gerenciales son un factor interno de las Pymes que influyen considerablemente en su competitividad empresarial

Propuesta de Diseño del Mantenimiento Centrado en la Confiabilidad de los Equipos de Pesado de Pollos para la Reducción de Costos en la Empresa Chimú Agropecuaria S.A.

La presente investigación estaba dirigida a elaborar la propuesta de implementación del mantenimiento centrado en la confiabilidad para disminuir los costos del proceso de pesaje de pollos en la empresa Chimú Agropecuaria S.A., para tal fin se empleó una metodología de tipo aplicada no experimental estimando como población a los 120 equipos de la cadena de producción y como muestra a los equipos del área de pesado. Además se emplearon hojas de registros, guías de observación y fichas de resumen como instrumentos para la recolección de datos, obteniendo como resultados que la balanza BACLA-01 Linco 180 era la más crítica con una calificación de 24 con un nivel de confiabilidad de 99,72%, además los costos totales de mantenimiento anual para el equipo fue de S/ 70430,45. Con ello se elaboró la propuesta en base al RCM empleando la hoja de decisiones para proponer 10 tareas de mantenimiento con sus respectivas frecuencias y responsables de ejecución además de un cronograma. Posteriormente se estimaron los costos nuevos de mantenimiento RCM, obteniendo un total de S/ 61764,00, representando un ahorro del 12,31%. Con ello se concluyó que la propuesta de implementar la metodología RCM beneficia económicamente y técnicamente a la empresa Chimú Agropecuaria S.A.The objective of this research was to elaborate the proposal for the implementation of maintenance focused on reliability to reduce the costs of the chicken weighing process in the company Chimú Agropecuaria S.A. For this purpose, a non-experimental applied methodology was used, estimating as population the 120 teams from the production line and, as a sample, the teams from the weighing area. In addition, record sheets, observation guides and summary sheets were used as instruments for data collection, obtaining as results that the BACLA-01 Linco 180 scale was the most critical with a rating of 24 with a reliability level of 99, 72%, in addition to the total annual maintenance costs for the equipment was S / 70430.45. With this, the proposal was prepared based on the RCM using the decision sheet to propose 10 maintenance tasks with their respective frequencies and responsible for execution as well as a schedule. Subsequently, the new RCM maintenance costs were estimated, obtaining a total of S/ 61,764.00, representing a saving of 12.31%. With this, it was concluded that the proposal to implement the RCM methodology economically and technically benefits the company Chimú Agropecuaria S.A.Tesi

Estrategia y objetivo de promoción de ventas utilizando las ventas personales y marketing directo

El tema de estudio es mezcla de marketing y el subtema es el análisis de las decisiones sobre promoción de los productos dando énfasis a las ventas personales y marketing directo. La mezcla de marketing es un conjunto de variables controlables que se combinan para lograr un determinado resultado en el mercado meta, el cual está conformado por las 4 P’s: Producto, Precio, Plaza y Promoción. El objetivo general del seminario es analizar las decisiones sobre la promoción de los productos, a través de los elementos derivados de la mezcla de marketing para dar énfasis a las ventas personales y marketing directo en función de la publicidad. La importancia de las ventas personales entre vendedor y comprador mediante la presentación de las funciones de las fuerzas de ventas va con el propósito de llevar a cabo las ventas y crear una buena relación con los clientes. La relación de la publicidad en la mezcla de marketing radica en la manera efectiva de llegar al consumidor, poder conocer sus gustos preferencias y cubrir las necesidades del cliente. Este documento se elaboró en base a la normativa para seminario de graduación con la aplicación de normas APA 6 y orientaciones del Departamento de Administración de Empresas, ya que es una investigación documental se trabajó con el uso de fuentes secundaria

International meta-analysis of PTSD genome-wide association studies identifies sex- and ancestry-specific genetic risk loci.

The risk of posttraumatic stress disorder (PTSD) following trauma is heritable, but robust common variants have yet to be identified. In a multi-ethnic cohort including over 30,000 PTSD cases and 170,000 controls we conduct a genome-wide association study of PTSD. We demonstrate SNP-based heritability estimates of 5-20%, varying by sex. Three genome-wide significant loci are identified, 2 in European and 1 in African-ancestry analyses. Analyses stratified by sex implicate 3 additional loci in men. Along with other novel genes and non-coding RNAs, a Parkinson's disease gene involved in dopamine regulation, PARK2, is associated with PTSD. Finally, we demonstrate that polygenic risk for PTSD is significantly predictive of re-experiencing symptoms in the Million Veteran Program dataset, although specific loci did not replicate. These results demonstrate the role of genetic variation in the biology of risk for PTSD and highlight the necessity of conducting sex-stratified analyses and expanding GWAS beyond European ancestry populations

Global genetic diversity of Aedes aegypti

Mosquitoes, especially Aedes aegypti, are becoming important models for studying invasion biology. We characterized genetic variation at 12 microsatellite loci in 79 populations of Ae. aegypti from 30 countries in six continents, and used them to infer historical and modern patterns of invasion. Our results support the two subspecies Ae. aegypti formosus and Ae. aegypti aegypti as genetically distinct units. Ae. aegypti aegypti populations outside Africa are derived from ancestral African populations and are monophyletic. The two subspecies co-occur in both East Africa (Kenya) and West Africa (Senegal). In rural/forest settings (Rabai District of Kenya), the two subspecies remain genetically distinct, whereas in urban settings, they introgress freely. Populations outside Africa are highly genetically structured likely due to a combination of recent founder effects, discrete discontinuous habitats and low migration rates. Ancestral populations in sub-Saharan Africa are less genetically structured, as are the populations in Asia. Introduction of Ae. aegypti to the New World coinciding with trans-Atlantic shipping in the 16th to 18th centuries was followed by its introduction to Asia in the late 19th century from the New World or from now extinct populations in the Mediterranean Basin. Aedes mascarensis is a genetically distinct sister species to Ae. aegypti s.l. This study provides a reference database of genetic diversity that can be used to determine the likely origin of new introductions that occur regularly for this invasive species. The genetic uniqueness of many populations and regions has important implications for attempts to control Ae. aegypti, especially for the methods using genetic modification of populations.Centro de Estudios Parasitológicos y de Vectore

Global genetic diversity of Aedes aegypti

Mosquitoes, especially Aedes aegypti, are becoming important models for studying invasion biology. We characterized genetic variation at 12 microsatellite loci in 79 populations of Ae. aegypti from 30 countries in six continents, and used them to infer historical and modern patterns of invasion. Our results support the two subspecies Ae. aegypti formosus and Ae. aegypti aegypti as genetically distinct units. Ae. aegypti aegypti populations outside Africa are derived from ancestral African populations and are monophyletic. The two subspecies co-occur in both East Africa (Kenya) and West Africa (Senegal). In rural/forest settings (Rabai District of Kenya), the two subspecies remain genetically distinct, whereas in urban settings, they introgress freely. Populations outside Africa are highly genetically structured likely due to a combination of recent founder effects, discrete discontinuous habitats and low migration rates. Ancestral populations in sub-Saharan Africa are less genetically structured, as are the populations in Asia. Introduction of Ae. aegypti to the New World coinciding with trans-Atlantic shipping in the 16th to 18th centuries was followed by its introduction to Asia in the late 19th century from the New World or from now extinct populations in the Mediterranean Basin. Aedes mascarensis is a genetically distinct sister species to Ae. aegypti s.l. This study provides a reference database of genetic diversity that can be used to determine the likely origin of new introductions that occur regularly for this invasive species. The genetic uniqueness of many populations and regions has important implications for attempts to control Ae. aegypti, especially for the methods using genetic modification of populations.Centro de Estudios Parasitológicos y de Vectore

Syndromes of self-reported psychopathology for ages 18-59 in 29 societies

This study tested the multi-society generalizability of an eight-syndrome assessment model derived from factor analyses of American adults' self-ratings of 120 behavioral, emotional, and social problems. The Adult Self-Report (ASR; Achenbach and Rescorla 2003) was completed by 17,152 18-59-year-olds in 29 societies. Confirmatory factor analyses tested the fit of self-ratings in each sample to the eight-syndrome model. The primary model fit index (Root Mean Square Error of Approximation) showed good model fit for all samples, while secondary indices showed acceptable to good fit. Only 5 (0.06%) of the 8,598 estimated parameters were outside the admissible parameter space. Confidence intervals indicated that sampling fluctuations could account for the deviant parameters. Results thus supported the tested model in societies differing widely in social, political, and economic systems, languages, ethnicities, religions, and geographical regions. Although other items, societies, and analytic methods might yield different results, the findings indicate that adults in very diverse societies were willing and able to rate themselves on the same standardized set of 120 problem items. Moreover, their self-ratings fit an eight-syndrome model previously derived from self-ratings by American adults. The support for the statistically derived syndrome model is consistent with previous findings for parent, teacher, and self-ratings of 11/2-18-year-olds in many societies. The ASR and its parallel collateral-report instrument, the Adult Behavior Checklist (ABCL), may offer mental health professionals practical tools for the multi-informant assessment of clinical constructs of adult psychopathology that appear to be meaningful across diverse societies