Celestial navigation in Drosophila

Many casual observers typecast Drosophila melanogaster as a stationary pest that lurks around fruit and wine. However, the omnipresent fruit fly, which thrives even in desert habitats, likely established and maintained its cosmopolitan status via migration over large spatial scales. To perform long-distance dispersal, flies must actively maintain a straight compass heading through the use of external orientation cues, such as those derived from the sky. In this Review, we address how D. melanogaster accomplishes long-distance navigation using celestial cues. We focus on behavioral and physiological studies indicating that fruit flies can navigate both to a pattern of linearly polarized light and to the position of the sun – the same cues utilized by more heralded insect navigators such as monarch butterflies and desert ants. In both cases, fruit flies perform menotaxis, selecting seemingly arbitrary headings that they then maintain over time. We discuss how the fly's nervous system detects and processes this sensory information to direct the steering maneuvers that underlie navigation. In particular, we highlight recent findings that compass neurons in the central complex, a set of midline neuropils, are essential for navigation. Taken together, these results suggest that fruit flies share an ancient, latent capacity for celestial navigation with other insects. Furthermore, they illustrate the potential of D. melanogaster to help us to elucidate both the cellular basis of navigation and mechanisms of directed dispersal on a landscape scale

The development of task performance across the worker lifespan

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El clima organizacional en el Centro de Educación Técnico Productivo “Almirante Miguel Grau” - Cercado de Lima - 2013

El presente trabajo es una investigación de tipo Descriptivo, cuyo diseño es No Experimental – Transeccional. Tiene como objetivo general identificar las características del clima organizacional del Centro de Educación Técnico Productivo Almirante Miguel Grau. Esta investigación justifica su importancia de trabajo porque un buen clima organizacional ayuda y alienta a ser competentes entre los compañeros de trabajo, creando una conducta madura de todos sus miembros, mejorando su rendimiento, productividad y satisfacción en el trabajo. La población estudiada fue de 35 docentes de una institución pública del distrito del Cercado de Lima. Para el recojo de datos se utilizó la técnica de la Encuesta con su instrumento el cuestionario. El instrumento aplicado fue de Luc Brunet. Los resultados demuestran que la variable y sus dimensiones son desfavorables al CETPRO Almirante Miguel Grau. Conociendo el impacto del clima organizacional, así como su gran importancia en la satisfacción laboral, surge la siguiente interrogante ¿Existe un clima organizacional favorable en Centro de Educación Técnica Productiva Almirante Miguel Grau? A partir de dicho resultado se muestran algunas recomendaciones para mejorar el clima organizacional

Celestial navigation in Drosophila

Many casual observers typecast Drosophila melanogaster as a stationary pest that lurks around fruit and wine. However, the omnipresent fruit fly, which thrives even in desert habitats, likely established and maintained its cosmopolitan status via migration over large spatial scales. To perform long-distance dispersal, flies must actively maintain a straight compass heading through the use of external orientation cues, such as those derived from the sky. In this Review, we address how D. melanogaster accomplishes long-distance navigation using celestial cues. We focus on behavioral and physiological studies indicating that fruit flies can navigate both to a pattern of linearly polarized light and to the position of the sun – the same cues utilized by more heralded insect navigators such as monarch butterflies and desert ants. In both cases, fruit flies perform menotaxis, selecting seemingly arbitrary headings that they then maintain over time. We discuss how the fly's nervous system detects and processes this sensory information to direct the steering maneuvers that underlie navigation. In particular, we highlight recent findings that compass neurons in the central complex, a set of midline neuropils, are essential for navigation. Taken together, these results suggest that fruit flies share an ancient, latent capacity for celestial navigation with other insects. Furthermore, they illustrate the potential of D. melanogaster to help us to elucidate both the cellular basis of navigation and mechanisms of directed dispersal on a landscape scale

A Veritable Menagerie of Heritable Bacteria from Ants, Butterflies, and Beyond: Broad Molecular Surveys and a Systematic Review

Maternally transmitted bacteria have been important players in the evolution of insects and other arthropods, affecting their nutrition, defense, development, and reproduction. Wolbachia are the best studied among these and typically the most prevalent. While several other bacteria have independently evolved a heritable lifestyle, less is known about their host ranges. Moreover, most groups of insects have not had their heritable microflora systematically surveyed across a broad range of their taxonomic diversity. To help remedy these shortcomings we used diagnostic PCR to screen for five groups of heritable symbionts—Arsenophonus spp., Cardinium hertigii, Hamiltonella defensa, Spiroplasma spp., and Wolbachia spp.—across the ants and lepidopterans (focusing, in the latter case, on two butterfly families—the Lycaenidae and Nymphalidae). We did not detect Cardinium or Hamiltonella in any host. Wolbachia were the most widespread, while Spiroplasma (ants and lepidopterans) and Arsenophonus (ants only) were present at low levels. Co-infections with different Wolbachia strains appeared especially common in ants and less so in lepidopterans. While no additional facultative heritable symbionts were found among ants using universal bacterial primers, microbes related to heritable enteric bacteria were detected in several hosts. In summary, our findings show that Wolbachia are the dominant heritable symbionts of ants and at least some lepidopterans. However, a systematic review of symbiont frequencies across host taxa revealed that this is not always the case across other arthropods. Furthermore, comparisons of symbiont frequencies revealed that the prevalence of Wolbachia and other heritable symbionts varies substantially across lower-level arthropod taxa. We discuss the correlates, potential causes, and implications of these patterns, providing hypotheses on host attributes that may shape the distributions of these influential bacteria.Organismic and Evolutionary Biolog

STRATIFIED RANDOMIZED RESPONSE MODELS: AN APPLICATION TO STUDENTS OF THE FACULTY OF MATHEMATICS OF THE UNMSM

In the present work, we study three stratified randomized response models, used in surveys that involve sensitive question (Kim and Elam, 2003). Made an application in the behavior of youths from the Faculty of Mathematical Sciences of San Marcos, to investigate the proportion of people who have consumed cocaine basic paste (CPB) at least once in life and the proportion of current users of the CPB and the proportion of people who had sex with more than two people for life and the proportion of people who consuming alcohol every weekend and the proportion of people who have been or are consumed without paying any products from a supermarket. The populations in study were students matriculated in the half-yearly 2009 - 11

DISEÑO MUESTRAL DE LA ENCUESTA DE OPINIÓN SOBRE INTENCIÓN DE VOTO EN LAS ELECCIONES MUNICIPALES Y PRESIDENCIALES: UNMSM

En el presente trabajo presentamos la metodología del diseño muestral en la encuesta de opinión de intención de voto de los alumnos de la UNMSM en las elecciones municipales del 2010 y en las presidenciales del 2011. Utilizamos el muestreo aleatorio estratificado con afijación proporcional al tamaño (Scheffer y Mendenhall, 2003) y se consideraron los siguientes estratos: Facultad de Ciencias Administrativas, Facultad de Ciencias Biológicas entre otras, en total veinte facultades de la UNMSM. Las encuestas se llevaron a cabo en tres etapas, durante los meses de julio, agosto y setiembre. En cada etapa se consideró a 500 participantes los cuales fueron seleccionados de cada una de las veinte facultades, siguiendo el esquema de muestreo estratificado con afijación proporcional Para el cálculo del tamaño de muestra se consideró un límite para el error de estimación del 4.41 %, con un nivel de confianza del 95% y la información proporcionada por el Sistema Único de Matricula (SUM), de los alumnos matriculados el primer semestre del año académico 2010

FACTORS THAT DETERMINATE THE TEENAGE MATERNITY. CASE: MATERNAL PERINATAL NATIONAL INSTITUTE

In the present work we identified the factors that affect in the teenager maternity in patients of the service of set accommodation of the Instituto Nacional Materno Perinatal (INMP) of Lima using of the theory of multiple logistic regression (Hosmer y Lemeshow, 2000; Uriel, 2005). We made a questionnaire and consider questions with respect to the features of the teenager mothers: education level, age of the union, knowledge of sex education and family planning, and so on. Features home: structure of the household, marital status of parents, union of parents, educational level of parents, number of brothers and sisters, and so on. The final data was taken from October the 2007 to March the 2008, with the application of the final instrument to mothers hospitalized in the services of set accommodation of the INMP. (Solano et. Al, 2007). For the calculus of the size of the samplc we used the proposed Freeman (1987); the mother were select at random until completed the size of the sample of two hundred forty two