Estudio sobre la prueba de las historietas de percibal m. symonds

OpenAIRE

Vargas Martínez, Gustavo

2012-01-01

Descripción básica - EI método S.P-S.T. (symonds picture-story tests) es una técnica de Contenido proyectivo dedicada al estudio de personalidad de los adolescentes, y pertenece a la misma clase de pruebas elaboradas sobre láminas con figuras reales, al estilo de "The Thematic Apperception Test" (TAT), Jackson, Blacky, etc. Tiene con ello, las mismas ventajas que presentan estas pruebas, cuales son las de facilitar expresiones existenciales de los examinados.

Evaluación de tres pruebas para el diagnóstico de geohelmintos en Colombia

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Myriam Consuelo López

2013-03-01

Full Text Available Introducción. Las geohelmintiasis son un problema de salud pública en países en vía de desarrollo. Los estudios de diagnóstico a nivel individual, así como los estudios de población, deben incorporar evaluaciones de su validez y fiabilidad. Objetivo. Comparar el examen directo, el método de Ritchie-Frick modificado, el de Kato-Katz brasilero y el de Kato-Katz de la OMS, para el diagnóstico de geohelmintos. Materiales y métodos. Se llevó a cabo un estudio de fiabilidad de pruebas diagnósticas. La misma muestra de materia fecal fue analizada por el mismo observador, empleando cuatro pruebas. Se recolectaron 204 muestras, de las cuales se analizaron 194 que cumplían los criterios de inclusión. Los observadores no conocían la identidad de los participantes, ni el resultado en las otras pruebas. Para el análisis se tomó como método de referencia, la prueba de Kato-Katz de la OMS. Para evaluar la fiabilidad se emplearon el porcentaje de concordancia, el porcentaje de concordancia positiva, la prueba estadística kappa y el coeficiente de correlación intraclase. Resultados. Se encontró un buen desempeño de la prueba brasilera de Kato-Katz, con alta sensibilidad y especificidad para Trichuris trichiura y Uncinaria sp., 0,97 y 0,96 respectivamente, en ambos valores, y alta especificidad y moderada sensibilidad para Ascaris lumbricoides (0,95 y 0,79, y un desempeño entre moderado y pobre para la prueba de Ritchie-Frick y el examen directo. Las diferencias fueron mayores para Uncinaria sp. y T. trichiura, que para A. lumbricoides. Conclusión. La prueba brasilera de Kato-Katz podría ser implementada, pero se necesitan más estudios para considerar la relación de su capacidad operativa con su factibilidad, disponibilidad y costo.   doi: http://dx.doi.org/10.7705/biomedica.v33i1.633

The importance of illumination in nest site choice and nest characteristics of cavity nesting birds.

Science.gov (United States)

Podkowa, Paweł; Surmacki, Adrian

2017-05-02

Light has a significant impact on many aspects of avian biology, physiology and behaviour. An increasing number of studies show that illumination may positively influences birds' offspring fitness by e.g. acceleration of embryo development, stimulation of skeleton growth or regulation of circadian rhythm. Because nest cavities have especially low illumination, suitable light levels may be especially important for species which nest there. We may therefore expect that birds breeding in relatively dim conditions should prefer brighter nest sites and/or evolve behavioral mechanisms to secure sufficient light levels in the nest. Using nest boxes with modified internal illumination, we experimentally tested whether light regime is a cue for nest site selection of secondary cavity-nesting species. Additionally, we investigated whether nest building strategies are tuned to internal illumination. Our results demonstrate that, nest boxes with elevated illumination were chosen twice as often as dark nest boxes. Moreover, birds built higher nests in dark nest boxes than birds in boxes with elevated illumination, which suggests a mechanism of compensating for low light conditions. Our results provide the first experimental support for the idea that nest site choice and nest building behaviour in cavity-nesting birds are influenced by ambient illumination.

Enclosed nests may provide greater thermal than nest predation benefits compared with open nests across latitudes

Science.gov (United States)

Martin, Thomas E.; Boyce, Andy J.; Fierro-Calderon, Karolina; Mitchell, Adam E.; Armstad, Connor E.; Mouton, James C.; Bin Soudi, Evertius E.

2017-01-01

Nest structure is thought to provide benefits that have fitness consequences for several taxa. Traditionally, reduced nest predation has been considered the primary benefit underlying evolution of nest structure, whereas thermal benefits have been considered a secondary or even non-existent factor. Yet, the relative roles of these factors on nest structures remain largely unexplored.Enclosed nests have a constructed or natural roof connected to sides that allow a restricted opening or tube entrance that provides cover in all directions except the entrance, whereas open nests are cups or platforms that are open above. We show that construction of enclosed nests is more common among songbirds (Passeriformes) in tropical and southern hemisphere regions than in north temperate regions. This geographic pattern may reflect selection from predation risk, under long-standing assumptions that nest predation rates are higher in southern regions and that enclosed nests reduce predation risk compared with open cup nests. We therefore compared nest predation rates between enclosed vs. open nests in 114 songbird species that do not nest in tree holes among five communities of coexisting birds, and for 205 non-hole-nesting species from the literature, across northern temperate, tropical, and southern hemisphere regions.Among coexisting species, enclosed nests had lower nest predation rates than open nests in two south temperate sites, but not in either of two tropical sites or a north temperate site. Nest predation did not differ between nest types at any latitude based on literature data. Among 319 species from both our field studies and the literature, enclosed nests did not show consistent benefits of reduced predation and, in fact, predation was not consistently higher in the tropics, contrary to long-standing perspectives.Thermal benefits of enclosed nests were indicated based on three indirect results. First, species that built enclosed nests were smaller than species using

RELACIÓN ENTRE DIFERENTES PRUEBAS DE CAMPO: FUERZA, POTENCIA Y VELOCIDAD

OpenAIRE

Jessenia Hernández Elizondo

2003-01-01

Esta investigación tuvo como propósito principal el encontrar por medio de pruebas en las variables de fuerza, potencia y velocidad, la relación matemática existente entre estos tres constructos. Participaron 56 sujetos varones con edades entre 18 y 25 años. Con el fin de responder al objetivo del estudio, se les aplicaron pruebas de campo de fuerza (1RM de sentadilla completa y repeticiones máximas al 80% 60% 40% y 20%), de velocidad (30 metros lanzados y 30 metros sin impulso), y de potenci...

La eficacia de la Prueba Indiciaria en el Proceso Penal Ecuatoriano

OpenAIRE

Pérez Medina, Lenin

2007-01-01

La eficacia de la prueba Indiciaria en el Proceso Penal Ecuatoriano, a tomado una nueva dimensión en nuestro sistema procesal, ya que a partir de la vigencia del nuevo Código de Procedimiento Penal, se ha orientado a garantizar la aplicación del debido proceso, en todos los parámetros que la constitución establece, en el presente trabajo estudiamos diferentes tópicos como presunción , sospecha , conjetura, vestigio, huella y rastro donde podría aparecer la prueba indiciaria, si...

Variantes psicosociales y el uso e interpretación de pruebas psicológicas

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Cecilia Thorne

1993-06-01

Full Text Available Se resalta la importancia de la adaptación, las normas y el análisis e interpretación cualitativa de los resultados. La autora ejemplifica cada uno de estos puntos a la luz de resultados de investigaciones llevadas a cabo en el medio con el WISC-R, Bender, Prueba deDiscriminación Auditiva, las Láminas de Evaluación.del Vocabulario y las Pruebas de Decodificación y Comprensión de Lectura Inicial. Se concluye que las pruebas pueden ser herramientas positivas de intervención y no simplemente ser utilizadas corno una constatación de diferencias entre grupos de distinto nivel sociocultural.

Proceso de pruebas para pequeñas organizaciones desarrolladoras de software

OpenAIRE

Martha Lucía Rojas-Montes; Francisco José Pino-Correa; James Mauricio Martínez

2015-01-01

Definir un proceso de pruebas dentro de una organización puede ser valioso en la medida en que permita: (i) incrementar la calidad del producto, (ii) facilitar la comunicación y la comprensión entre los miembros del equipo, (iii) apoyar la mejora continua del proceso, y (iv) soportar la ejecución automática de ciertas tareas. En este sentido, este artículo propone un proceso liviano definido para guiar y apoyar la realización de las pruebas en pequeñas organizaciones desarrolladoras de softwa...

Evaluación de la prueba del reloj en el tamizaje de enfermedad de Alzheimer

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Teodoro Oscanoa

2004-03-01

Full Text Available Objetivo: Examinar la capacidad discriminativa de la prueba del reloj con 10 puntos en el tamizaje de trastorno cognoscitivo por enfermedad de Alzheimer. Material y Métodos: Evaluación de una prueba diagnóstica mediante estudio de pacientes con y sin enfermedad de Alzheimer, provenientes del Consultorio Externo del Servicio de Geriatría del Hospital Almenara, Lima, Perú. Participaron 31 pacientes (10 varones y 21 mujeres con enfermedad de Alzheimer y 31 pacientes sin esta enfermedad (21 varones y 10 mujeres. A ambos grupos se les realizó el prueba del reloj. No hubo diferencia significativa entre la edad y grado de instrucción de ambos grupos. La gravedad de la demencia según el Clinical Dementia Ratio de Hughes fue leve en 10 (32,3%, moderada 12 (38,7% y severa en 9 (29%. Resultados: Considerando como punto de corte un valor de 6 en la prueba del reloj, se encontró una sensibilidad de 83,9%, especificidad 93,5%, valor predictivo positivo 92,9 y valor predictivo negativo 85,3%. Conclusión: La prueba del reloj parece ser un examen simple y efectivo para la evaluación inicial de trastornos cognitivos en pacientes adultos mayores con sospecha de demencia por enfermedad de Alzheimer.

Consideraciones especiales para realizar pruebas de usabilidad con niños: Caso de Estudio

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María Esperanza Pérez Cordoba Sánchez

2015-02-01

Full Text Available Cuando se aplican pruebas de usabilidad se espera que los resultados arrojen un diagnóstico con respecto a la facilidad de uso y del grado de satisfacción de los usuarios. Se sabe desde hace mucho tiempo que el diseño de las interfaces es parte crucial en la percepción que se tiene del sistema, para lograr un buen diseño es necesario conocer de antemano quién es el usuario final y después se tienen que cubrir las necesidades de uso. Esto es especialmente cierto cuando se trabaja con niños, dado que influyen factores como la forma en la que aprenden, sus gustos, el grado de distracción, su facilidad para seguir indicaciones, la motivación para ejecutar las tareas e incluso cuestiones como la ergonomía. En el presente trabajo se reportan algunos hallazgos que resultaron de realizar pruebas de usabilidad con niños a un sistema interactivo controlado por Kinect. Se describe la metodología usada durante las pruebas así como los aspectos y diferencias que existen con respecto a las pruebas de usabilidad con adultos. También se incluye una revisión bibliográfica de trabajos publicados que tratan el tema de pruebas de usabilidad con niños, con lo que se busca dar soporte al presente trabajo.

Influence of olfactory and visual cover on nest site selection and nest success for grassland-nesting birds.

Science.gov (United States)

Fogarty, Dillon T; Elmore, R Dwayne; Fuhlendorf, Samuel D; Loss, Scott R

2017-08-01

Habitat selection by animals is influenced by and mitigates the effects of predation and environmental extremes. For birds, nest site selection is crucial to offspring production because nests are exposed to extreme weather and predation pressure. Predators that forage using olfaction often dominate nest predator communities; therefore, factors that influence olfactory detection (e.g., airflow and weather variables, including turbulence and moisture) should influence nest site selection and survival. However, few studies have assessed the importance of olfactory cover for habitat selection and survival. We assessed whether ground-nesting birds select nest sites based on visual and/or olfactory cover. Additionally, we assessed the importance of visual cover and airflow and weather variables associated with olfactory cover in influencing nest survival. In managed grasslands in Oklahoma, USA, we monitored nests of Northern Bobwhite ( Colinus virginianus ), Eastern Meadowlark ( Sturnella magna ), and Grasshopper Sparrow ( Ammodramus savannarum ) during 2015 and 2016. To assess nest site selection, we compared cover variables between nests and random points. To assess factors influencing nest survival, we used visual cover and olfactory-related measurements (i.e., airflow and weather variables) to model daily nest survival. For nest site selection, nest sites had greater overhead visual cover than random points, but no other significant differences were found. Weather variables hypothesized to influence olfactory detection, specifically precipitation and relative humidity, were the best predictors of and were positively related to daily nest survival. Selection for overhead cover likely contributed to mitigation of thermal extremes and possibly reduced detectability of nests. For daily nest survival, we hypothesize that major nest predators focused on prey other than the monitored species' nests during high moisture conditions, thus increasing nest survival on these

Diagnóstico de proliferación bacteriana intestinal en niños: evidencia experimental para sustentar el empleo de lactulosa en la prueba de hidrógeno y su validación como prueba tamiz

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Evelyn Mendoza

2007-09-01

Conclusiones. Se aporta evidencia experimental para sustentar el uso de la lactulosa en la prueba de hidrógeno y se valida ésta frente al patrón de referencia como prueba tamiz para diagnosticar la proliferación bacteriana intestinal.

The cavity-nest ant Temnothorax crassispinus prefers larger nests.

Science.gov (United States)

Mitrus, S

Colonies of the ant Temnothorax crassispinus inhabit mostly cavities in wood and hollow acorns. Typically in the field, nest sites that can be used by the ant are a limited resource. In a field experiment, it was investigated whether the ants prefer a specific size of nest, when different ones are available. In July 2011, a total of 160 artificial nests were placed in a beech-pine forest. Four artificial nests (pieces of wood with volume cavities, ca 415, 605, 730, and 980 mm 3 , respectively) were located on each square meter of the experimental plot. One year later, shortly before the emergence of new sexuals, the nests were collected. In July 2012, colonies inhabited more frequently bigger nests. Among queenright colonies, the ones which inhabited bigger nests had more workers. However, there was no relationship between volume of nest and number of workers for queenless colonies. Queenright colonies from bigger nests produced more sexual individuals, but there was no correlation between number of workers and sex allocation ratio, or between volume of nest and sex allocation ratio. In a laboratory experiment where ant colonies were kept in 470 and 860 mm 3 nests, larger colonies allocated more energy to produce sexual individuals. The results of this study show the selectivity of T. crassispinus ants regarding the size of nest cavity, and that the nest volume has an impact on life history parameters.

The influence of nest-site characteristics on the nesting success of ...

African Journals Online (AJOL)

Choice of nest site has important consequences for nest survival. We examined nest-site characteristics relative to nest success in Karoo Prinias breeding in coastal dwarf shrubland, where high nest predation is the main cause of nest failure. Initially, we compared nests that failed during the building, laying, incubation and ...

La falacia de los datos de prueba

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Martín Uribe Arbeláez

2012-11-01

Full Text Available El artículo analiza la protección de los datos de prueba mediante un derecho de exclusividad y las vicisitudes por las que pasó su adopción en Colombia. Considera la manera como se protegían en los Acuerdos ADPIC, la controversia en la Comunidad Andina de Naciones, el retiro de Venezuela tras la aprobación de la Decisión 632 de 2006, el resquebrajamiento del Régimen Común de Propiedad Industrial, lo dispuesto en el “Acuerdo de Promoción Comercial” (TLC Colombia-Estados Unidos y en su Protocolo Modificatorio. También examina los requisitos exigidos para que opere esta protección, la falacia de los “medicamentos me too”, y formula recomendaciones para una estricta aplicación dentro del actual marco normativo, al igual que subrayan las flexibilidades de las que se puede hacer uso en virtud del Protocolo Modificatorio al TLC, Ley 1166 de 2007. El estudio del impacto en el precio de los medicamentos como consecuencia de la exclusividad de los datos de prueba y la defensa del derecho fundamental a la salud arroja claridad en un tema caracterizado por los tecnicismos y los artificios jurídicos.

Do artificial nests simulate nest success of greater sage-grouse?

OpenAIRE

Dinkins, Jonathan B.; Conover, Michael R.; Mabray, Scott T.

2013-01-01

Artificial nests have been used to study factors affecting nest success because researchers can manipulate them more than natural bird nests. Many researchers have questioned the validity of generalizing the results from artificial nests onto naturally occurring nests. Other studies have assessed the validity of artificial nest studies by simultaneously comparing overall depredation or daily survival rates, depredation timing, predator species, or habitat characteristics of artificial and nat...

Aplicación práctica del diseño de pruebas de software a nivel de programación

OpenAIRE

Guzmán Cortés, Oscar Hernando

2006-01-01

Las pruebas deben presentarse a lo largo de todo el ciclo de vida del desarrollo de software, pasando por requerimientos, análisis y diseño, programación, puesta en marcha y mantenimiento. El siguiente artículo presenta el esquema de diseño y ejecución de pruebas de software, centrándose específicamente en las pruebas de programación, definidas para el departamento de Desarrollo de Sistemas de la Universidad Icesi. El esquema de pruebas de requerimientos se muestra de manera general, mien...

PyNEST: a convenient interface to the NEST simulator

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Jochen M Eppler

2009-01-01

Full Text Available The neural simulation tool NEST (http://www.nest-initiative.org is a simulator for heterogeneous networks of point neurons or neurons with a small number of compartments. It aims at simulations of large neural systems with more than 10^4 neurons and 10^7 to 10^9 synapses. NEST is implemented in C++ and can be used on a large range of architectures from single-core laptops over multi-core desktop computers to super-computers with thousands of processor cores. Python (http://www.python.org is a modern programming language that has recently received considerable attention in Computational Neuroscience. Python is easy to learn and has many extension modules for scientific computing (e.g. http://www.scipy.org. In this contribution we describe PyNEST, the new user interface to NEST. PyNEST combines NEST’s efficient simulation kernel with the simplicity and flexibility of Python. Compared to NEST’s native simulation language SLI, PyNEST makes it easier to set up simulations, generate stimuli, and analyze simulation results. We describe how PyNEST connects NEST and Python and how it is implemented. With a number of examples, we illustrate how it is used.

Variability in nest survival rates and implications to nesting studies

Science.gov (United States)

Klett, A.T.; Johnson, D.H.

1982-01-01

We used four reasonably large samples (83-213) of Mallard (Anas platyrhynchos) and Blue-winged Teal (A. discors) nests on an interstate highway right-of-way in southcentral North Dakota to evaluate potential biases in hatch-rate estimates. Twelve consecutive, weekly searches for nests were conducted with a cable-chain drag in 1976 and 1977. Nests were revisited at weekly intervals. Four methods were used to estimate hatch rates for the four data sets: the Traditional Method, the Mayfield Method, and two modifications of the Mayfield Method that are sometimes appropriate when daily mortality rates of nests are not constant. Hatch rates and the average age of nests at discovery declined as the interval between searches decreased, suggesting that mortality rates were not constant in our samples. An analysis of variance indicated that daily mortality rates varied with the age of nests in all four samples. Mortality was generally highest during the early laying period, moderately high during the late laying period, and lowest during incubation. We speculate that this relationship of mortality to nest age might be due to the presence of hens at nests or to differences in the vulnerability of nest sites to predation. A modification of the Mayfield Method that accounts for age-related variation in nest mortality was most appropriate for our samples. We suggest methods for conducting nesting studies and estimating nest success for species possessing similar nesting habits.

Diseño, fabricación y prueba de una antena de parche para GPS en aplicaciones automotrices Diseño, fabricación y prueba de una antena de parche para GPS en aplicaciones automotrices

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S. V Koshevaya

2012-02-01

Full Text Available This work is focused on the development of a prototype patch antenna designed for use asa replacement antenna in automotive Global Positioning Systems (GPS. In simulations andtesting of the prototype, the focus was on the antenna gain. Transmission-reception testingwas done to verify the operation frequency. The prototype was tested with a commercial GPSkit to evaluate its performance as a replacement antenna. Laboratory testing showed that itcomplied with the minimum requirements for both reception and transmission frequencies,while testing on a stationary vehicle showed slight variations when compared to the positiondata obtained using the same kit with its original antenna. In non-stationary testing, positiondeterminations made with the prototype were sufficiently precise for use.Este trabajo se centra en el desarrollo de una antena de parche diseñada para Sistemas de Posicionamiento Global (GPS, con la finalidad de emplearla como antena de reemplazo en aplicaciones automotrices. En las simulaciones y pruebas se pone énfasis en su ganancia. Las pruebas de transmisión-recepción se realizaron para verificar que la frecuencia de operación de la antena fabricada sea la adecuada. Las pruebas con un kit de GPS comercial fueron realizadas para comparar su desempeño como antena de reemplazo. Las pruebas de laboratorio muestran que se cumple con el mínimo requerido para cubrir ambas frecuencias, de recepción y de transmisión, mientras que las pruebas del prototipo, en el techo vehículo sin movimiento, mostraron ligeras variaciones en los datos de posición, comparados con los obtenidos con el kit con su antena original. Las pruebas de viaje mostraron la suficiente precisión en la determinación de la posición para su uso.

Auscultación y pruebas de carga

OpenAIRE

Sánchez García, Ibán

2011-01-01

[ES] Trata sobre la auscultación de estructuras. Los diferentes tipos de pruebas de carga,en puentes de carretera y en puentes de ferrocarril, además de los aparatos de medida y forma de ejecutarlas. [EN] Explains auscultation of structures. The different types of load tests on road bridges and railway bridges, plus the measuring apparatus and method of executing them. Proyecto Fin de Carrera-Universidad de Salamanca, Escuela Politécnica Superior de Zamora, 2011

Why wasp foundresses change nests: relatedness, dominance, and nest quality.

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Perttu Seppä

Full Text Available The costs and benefits of different social options are best understood when individuals can be followed as they make different choices, something that can be difficult in social insects. In this detailed study, we follow overwintered females of the social wasp Polistes carolina through different nesting strategies in a stratified habitat where nest site quality varies with proximity to a foraging area, and genetic relatedness among females is known. Females may initiate nests, join nests temporarily or permanently, or abandon nests. Females can become helpers or egglayers, effectively workers or queens. What they actually do can be predicted by a combination of ecological and relatedness factors. Advantages through increased lifetime success of individuals and nests drives foundresses of the social wasp Polistes from solitary to social nest founding. We studied reproductive options of spring foundresses of P. carolina by monitoring individually-marked wasps and assessing reproductive success of each foundress by using DNA microsatellites. We examined what behavioral decisions foundresses make after relaxing a strong ecological constraint, shortage of nesting sites. We also look at the reproductive consequences of different behaviors. As in other Polistes, the most successful strategy for a foundress was to initiate a nest as early as possible and then accept others as subordinates. A common feature for many P. carolina foundresses was, however, that they reassessed their reproductive options by actively monitoring other nests at the field site and sometimes moving permanently to new nests should that offer better (inclusive fitness prospects compared to their original nests. A clear motivation for moving to new nests was high genetic relatedness; by the end of the foundress period all females were on nests with full sisters.

Why Wasp Foundresses Change Nests: Relatedness, Dominance, and Nest Quality

Science.gov (United States)

Seppä, Perttu; Queller, David C.; Strassmann, Joan E.

2012-01-01

The costs and benefits of different social options are best understood when individuals can be followed as they make different choices, something that can be difficult in social insects. In this detailed study, we follow overwintered females of the social wasp Polistes carolina through different nesting strategies in a stratified habitat where nest site quality varies with proximity to a foraging area, and genetic relatedness among females is known. Females may initiate nests, join nests temporarily or permanently, or abandon nests. Females can become helpers or egglayers, effectively workers or queens. What they actually do can be predicted by a combination of ecological and relatedness factors. Advantages through increased lifetime success of individuals and nests drives foundresses of the social wasp Polistes from solitary to social nest founding. We studied reproductive options of spring foundresses of P. carolina by monitoring individually-marked wasps and assessing reproductive success of each foundress by using DNA microsatellites. We examined what behavioral decisions foundresses make after relaxing a strong ecological constraint, shortage of nesting sites. We also look at the reproductive consequences of different behaviors. As in other Polistes, the most successful strategy for a foundress was to initiate a nest as early as possible and then accept others as subordinates. A common feature for many P. carolina foundresses was, however, that they reassessed their reproductive options by actively monitoring other nests at the field site and sometimes moving permanently to new nests should that offer better (inclusive) fitness prospects compared to their original nests. A clear motivation for moving to new nests was high genetic relatedness; by the end of the foundress period all females were on nests with full sisters. PMID:23049791

Nest Predation Deviates from Nest Predator Abundance in an Ecologically Trapped Bird.

Science.gov (United States)

Hollander, Franck A; Van Dyck, Hans; San Martin, Gilles; Titeux, Nicolas

2015-01-01

In human-modified environments, ecological traps may result from a preference for low-quality habitat where survival or reproductive success is lower than in high-quality habitat. It has often been shown that low reproductive success for birds in preferred habitat types was due to higher nest predator abundance. However, between-habitat differences in nest predation may only weakly correlate with differences in nest predator abundance. An ecological trap is at work in a farmland bird (Lanius collurio) that recently expanded its breeding habitat into open areas in plantation forests. This passerine bird shows a strong preference for forest habitat, but it has a higher nest success in farmland. We tested whether higher abundance of nest predators in the preferred habitat or, alternatively, a decoupling of nest predator abundance and nest predation explained this observed pattern of maladaptive habitat selection. More than 90% of brood failures were attributed to nest predation. Nest predator abundance was more than 50% higher in farmland, but nest predation was 17% higher in forest. Differences between nest predation on actual shrike nests and on artificial nests suggested that parent shrikes may facilitate nest disclosure for predators in forest more than they do in farmland. The level of caution by parent shrikes when visiting their nest during a simulated nest predator intrusion was the same in the two habitats, but nest concealment was considerably lower in forest, which contributes to explaining the higher nest predation in this habitat. We conclude that a decoupling of nest predator abundance and nest predation may create ecological traps in human-modified environments.

Nest Site Characteristics of Cavity Nesting Birds in Central Missouri

Science.gov (United States)

Jeffery D. Brawn; Bernice Tannenbaum; Keith E. Evans

1984-01-01

Two study sites in central Missouri oak-hickory forests were searched for nest sites of cavity nesting birds. Researchers located and measured 133 nests of 11 species. Cavity nesting bird habitat selection is affected by both snag characteristics and vegetation structure.

Validación de una prueba computarizada de lectura inicial en niños escolares colombianos

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Natalia Cadavid-Ruiz

2016-01-01

Full Text Available Con el objetivo de validar la prueba de evaluación de competencia lectora ABCDeti en población infantil colombiana, se evalua - ron 265 niños, entre los 5 y 8 años de edad, que cursaban entre transición y segundo de primaria, residentes en la ciudad de Cali (Co - lombia. Todos los participantes del estudio fueron evaluados con las pruebas ABCDeti y las dimensiones de Habilidades Metalin - güísticas y Lectura de la batería Evaluación Neuropsicológica Infantil. Los resultados demuestran que esta prueba presenta una consistencia interna, para los diferentes gra - dos escolares evaluados, entre .68 y .74. Entre tanto, la validez convergente oscila entre α = .68 a .79 en los grados evaluados. El análisis factorial realizado a los datos recogidos, por grado escolar, explican entre un 45% y 54% la varianza de los datos. En conclusión, la prueba ABCDeti es un instrumento fiable para evaluar la lectura inicial de niños colombianos.

Propuesta para incorporar evaluación y pruebas de usabilidad dentro de un proceso de desarrollo de software

OpenAIRE

Florian Gaviria, Beatriz Eugenia; Solarte, Oswaldo; Reyes, Javier M.

2010-01-01

La usabilidad es crítica para el éxito de los sistemas de software interactivos. Las pruebas y evaluaciones de usabilidad durante el desarrollo del producto han ganado amplia aceptación como estrategia para mejorar la calidad del producto. La introducción temprana de las perspectivas de usabilidad en un producto es muy importante para brindar una clara visibilidad de aspectos de calidad, tanto para los desarrolladores como los usuarios de pruebas. Sin embargo, la evaluación y pruebas de usabi...

¿ Es útil la prueba de lipemia predonación para la selección de donantes de sangre?

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Pedro Sánchez Frenes

Full Text Available En el Banco de Sangre Provincial de Cienfuegos se incluye, además de las pruebas reguladas en Cuba para la selección de los donantes de sangre, la prueba de lipemia predonación. Un plasma con apariencia turbia es causa de exclusión transitoria del donante. A fin de evaluar la eficacia diagnóstica de esta prueba se realizaron dos estimaciones visuales del plasma en busca de turbidez, la primera antes de donar y la segunda en la unidad de plasma obtenida a partir de la sangre total colectada, esta última utilizada como prueba de referencia para este estudio. Ambas observaciones fueron realizadas por el mismo observador siguiendo un protocolo establecido. Como parte del estudio, la presencia de una prueba de lipemia positiva predonación no constituyó causa de exclusión de donantes. Se calculó la sensibilidad y especificidad diagnóstica, el valor predictivo positivo (VPP y el valor predictivo negativo (VPN, además la eficiencia de la prueba dentro de un intervalo de confianza del 95 %. Se obtuvo el 98,4 % de especificidad, el 80 % de sensibilidad, así como el 66,6 % de valor predictivo positivo y el 99,0 % de valor predictivo negativo, con el 95,7 % de eficiencia diagnóstica. La prueba resulta útil en la selección de donantes de sangre y se recomienda su uso en todas las dependencias de colecta de sangre que cuenten con las condiciones técnicas para su realización.

Nest Predation Deviates from Nest Predator Abundance in an Ecologically Trapped Bird.

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Franck A Hollander

Full Text Available In human-modified environments, ecological traps may result from a preference for low-quality habitat where survival or reproductive success is lower than in high-quality habitat. It has often been shown that low reproductive success for birds in preferred habitat types was due to higher nest predator abundance. However, between-habitat differences in nest predation may only weakly correlate with differences in nest predator abundance. An ecological trap is at work in a farmland bird (Lanius collurio that recently expanded its breeding habitat into open areas in plantation forests. This passerine bird shows a strong preference for forest habitat, but it has a higher nest success in farmland. We tested whether higher abundance of nest predators in the preferred habitat or, alternatively, a decoupling of nest predator abundance and nest predation explained this observed pattern of maladaptive habitat selection. More than 90% of brood failures were attributed to nest predation. Nest predator abundance was more than 50% higher in farmland, but nest predation was 17% higher in forest. Differences between nest predation on actual shrike nests and on artificial nests suggested that parent shrikes may facilitate nest disclosure for predators in forest more than they do in farmland. The level of caution by parent shrikes when visiting their nest during a simulated nest predator intrusion was the same in the two habitats, but nest concealment was considerably lower in forest, which contributes to explaining the higher nest predation in this habitat. We conclude that a decoupling of nest predator abundance and nest predation may create ecological traps in human-modified environments.

EL CONOCIMIENTO DEL DOMINIO COMO VALOR AGREGADO AL PLAN DE PRUEBAS

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LOURDES PRADO

2011-12-01

Full Text Available El conocimiento del dominio es el área de especialización relacionada con el entorno de la aplicación, mientras que el conocimiento técnico es la tecnología utilizada para generar la aplicación y el conocimiento o know-how para ejecutar las actividades del día a día para realizar una tarea. Con base en estas definiciones el conocimiento de dominio sería la telefonía móvil, VoIP, la banca, el comercio electrónico o las aplicaciones de atención médica, y los conocimientos técnicos serían los protocolos, las redes, los lenguajes de programación, la web, los motores de búsqueda, las pruebas SOAP, o la automatización. Conocer ese dominio es de suma importancia en el mundo de las pruebas, ya que le da ventajas a los probadores para diseñar escenarios de prueba lo más cercanos a la vida real. En este trabajo se hace una descripción de las ventajas de conocer el domino del producto y se sustenta la importancia de contar con probadores expertos en el dominio de la aplicación para entregar software de mayor calidad.

La prueba pericial en los delitos financieros

OpenAIRE

Barrios Ortega , Cecilia Ilusión

2016-01-01

La utilidad del peritaje como medio de prueba en el proceso penal es un tema históricamente establecido. Su pertinencia y uso en los delitos de cuello azul, los delitos violentes asociados a la delincuencia común, hombre de poco estudio y clase social baja, es notoria (necropsias en homicidios, dictámenes en lesiones, violaciones, grafotecnia en estafas, fraudes). Pero el delito evoluciona con el hombre y el aparecimiento de los delitos de cuello blanco, cometidos por hombres estu...

Prueba de grupo. Una eficiente alternativa para estimar prevalencia animal

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Osval Antonio Montesinos López

2012-01-01

Full Text Available La estimación de prevalencia animal o detección de agentes infecciosos, es de vital importancia para una nación o estado para proteger su seguridad alimentaria y garantizar el comercio local y exterior. Sin embargo, realizar estas dos tareas (estimación y detección eficientemente requiere de significativos recursos materiales y humanos. Por ello, el presente artículo presenta una revisión del proceso de estimación y detección usando la técnica estadística conocida como prueba de grupo (group testing que puede contribuir al ahorro de recursos cuantiosos para la estimación y detección de enfermedades infecciosas en ciencia animal cuando la prevalencia es menor o igual al 10%. Group testing es una ingeniosa técnica estadística propuesta por Dorfman (1943. Esta técnica consiste en juntar el material de k individuos, mezclarlos perfectamente y en lugar de realizar una prueba de laboratorio para cada individuo, se realiza una sola prueba con la mezcla de los k individuos. De esta forma se logran ahorros significativos. Por ello, se muestra el funcionamiento de algunos métodos para clasificar individuos; se expone el proceso de estimación puntual y por intervalo de prevalencia animal; y se ilustra el cálculo del tamaño de muestra bajo este modelo, con la finalidad de que los investigadores en ciencia animal la utilicen y ahorren recursos significativos.

Nest use is influenced by the positions of nests and drinkers in aviaries.

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Lentfer, T L; Gebhardt-Henrich, S G; Fröhlich, E K F; von Borell, E

2013-06-01

The influence of the nest location and the placement of nipple drinkers on nest use by laying hens in a commercial aviary was assessed. Twenty pens in a laying hen house were equipped with the same commercial aviary system, but the pens differed in the nest location and the placement of nipple drinkers. Nests were placed along the walls in 10 pens, and nipple drinkers were installed in front of the nests in 5 of these pens. The other 10 pens were equipped with nests placed on a tier within the aviary (integrated nests). Nipple drinkers were installed in front of the nests in 5 of these pens. A total of 225 Lohmann Selected Leghorns were housed per pen. The hens were offered 4 nests per pen: 2 facing the service corridor of the laying hen house and 2 facing the outdoor area. The numbers of nest eggs and mislaid eggs were counted daily per pen. At 25, 36, and 43 wk of age, the nest platforms were videotaped and the behavior of laying hens in front of the nests was analyzed. The nest location affected the stationary and locomotive behaviors in front of the nests. Hens in front of the integrated nests and the nests with drinkers displayed more stationary behaviors than hens in front of wall-placed nests or nests without drinkers. No difference in the number of nest eggs could be detected, but the integration of the nests inside the aviary led to a more even distribution of hens while nest searching. In the pens with wall-placed nests, significantly more hens laid eggs in the nests at the wall near the service corridor than at the wall near the outdoor area. Due to this imbalance, crowding in front of the preferred nests occurred and pushing and agonistic interactions on the nest platforms were significantly more frequent. Placement of nipple drinkers in front of nests had no effect on the number of eggs laid in those nests.

Interactive effects between nest microclimate and nest vegetation structure confirm microclimate thresholds for Lesser Prairie-Chicken nest survival

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Grisham, Blake A.; Godar, Alixandra J.; Boal, Clint W.; Haukos, David A.

2016-01-01

The range of Lesser Prairie-Chickens (Tympanuchus pallidicinctus) spans 4 unique ecoregions along 2 distinct environmental gradients. The Sand Shinnery Oak Prairie ecoregion of the Southern High Plains of New Mexico and Texas is environmentally isolated, warmer, and more arid than the Short-Grass, Sand Sagebrush, and Mixed-Grass Prairie ecoregions in Colorado, Kansas, Oklahoma, and the northeast panhandle of Texas. Weather is known to influence Lesser Prairie-Chicken nest survival in the Sand Shinnery Oak Prairie ecoregion; regional variation may also influence nest microclimate and, ultimately, survival during incubation. To address this question, we placed data loggers adjacent to nests during incubation to quantify temperature and humidity distribution functions in 3 ecoregions. We developed a suite of a priori nest survival models that incorporated derived microclimate parameters and visual obstruction as covariates in Program MARK. We monitored 49 nests in Mixed-Grass, 22 nests in Sand Shinnery Oak, and 30 nests in Short-Grass ecoregions from 2010 to 2014. Our findings indicated that (1) the Sand Shinnery Oak Prairie ecoregion was hotter and drier during incubation than the Mixed- and Short-Grass ecoregions; (2) nest microclimate varied among years within ecoregions; (3) visual obstruction was positively associated with nest survival; but (4) daily nest survival probability decreased by 10% every half-hour when temperature was greater than 34°C and vapor pressure deficit was less than −23 mmHg during the day (about 0600–2100 hours). Our major finding confirmed microclimate thresholds for nest survival under natural conditions across the species' distribution, although Lesser Prairie-Chickens are more likely to experience microclimate conditions that result in nest failures in the Sand Shinnery Oak Prairie ecoregion. The species would benefit from identification of thermal landscapes and management actions that promote cooler, more humid nest microclimates.

Nest Mosquito Trap quantifies contact rates between nesting birds and mosquitoes.

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Caillouët, Kevin A; Riggan, Anna E; Rider, Mark; Bulluck, Lesley P

2012-06-01

Accurate estimates of host-vector contact rates are required for precise determination of arbovirus transmission intensity. We designed and tested a novel mosquito collection device, the Nest Mosquito Trap (NMT), to collect mosquitoes as they attempt to feed on unrestrained nesting birds in artificial nest boxes. In the laboratory, the NMT collected nearly one-third of the mosquitoes introduced to the nest boxes. We then used these laboratory data to estimate our capture efficiency of field-collected bird-seeking mosquitoes collected over 66 trap nights. We estimated that 7.5 mosquitoes per trap night attempted to feed on nesting birds in artificial nest boxes. Presence of the NMT did not have a negative effect on avian nest success when compared to occupied nest boxes that were not sampled with the trap. Future studies using the NMT may elucidate the role of nestlings in arbovirus transmission and further refine estimates of nesting bird and vector contact rates. © 2012 The Society for Vector Ecology.

Simulacro de las pruebas internacionales: una mirada desde los estándares de lengua

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Jaddy Brigitte Nielsen Nino

2017-03-01

Full Text Available El siguiente artículo tiene como objetivo principal comparar los resultados finales de las asignaturas de los cursos modulares y su relación con las pruebas internacionales correspondiente a cada nivel de acuerdo con el Marco Común Europeo que se ha establecido en la ruta académica del programa de licenciatura en inglés. Se parte del resultado inicial del curso intersemestral para la preparación de pruebas internacionales y así se puede determinar el dominio de una lengua extranjera del estudiante de la Licenciatura en Inglés de la Facultad de Ciencias de la Educación de la Universidad la Gran Colombia, sede Bogotá. Los resultados arrojados a través de pruebas post y pre demuestran que existen algunos factores que influyen en el bajo dominio de la lengua tales como falencias en conceptos básicos, la autonomía, motivación y tiempo de dedicación además el incremento en la deserción de los estudiantes, siendo un curso libre impartido por profesionales expertos. Se concluye, que los cursos intersemestrales para la preparación de una prueba internacional no basta con realizar simulaciones de dichos exámenes sino que generar unas metas claras que permitan concluir adecuadamente la ruta académica propuesta dentro del currículo.

Comentarios alrededor de 1789 pruebas de Uropepsina

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Ernesto Andrade Valderrama

1956-08-01

Full Text Available Se presenta la experiencia con uropepsina; 1789 pruebas realizadas y 390 casos, completamente estudiados. Se hace un comentario sobre la casuística general, las cifras promedio y las cifras medias encontrada entre nosotros. En los normales esta es de 29.9. En la úlcera gástrica 62.9. En la duodenal 85.8. En el cáncer gástrico 19.1. Se explica la técnica empleada, que es la de goodman a la cual le introducimos modificaciones originales: La utilización de controles positivos y negativo, que hacen más segura la interpretación de los resultados. Se presentan los experimentos practicados con un ganglio metastásico, de los cuales se deduce que allí se encontró un zimógeno con todos los caracteres del pepsinógeno. Se recalca en el valor pronóstico de la prueba de la uropepsina, especialmente en la úlcera duodenal y en el carcinoma gástrico. La aparición de uropepsina después de gastrectomía total por cáncer, indica la presencia de metástasis. El tipo de gastrectomía que da cifras más bajas y persistentes de uropepsina es la fundo-corporal. El ACTH estimula la producción de pepsinógeno en individuos normales, gastrectomizados tipo billroth y gastrectomizados totales con metástasis.

Mourning Dove nesting habitat and nest success in Central Missouri

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Drobney, R.D.; Schulz, J.H.; Sheriff, S.L.; Fuemmeler, W.J.

1998-01-01

Previous Mourning Dove (Zenaida macroura) nesting studies conducted in areas containing a mixture of edge and continuous habitats have focused on edge habitats. Consequently, little is known about the potential contribution of continuous habitats to dove production. In this study we evaluated the relative importance of these two extensive habitat types by monitoring the habitat use and nest success of 59 radio-marked doves during 1990-1991 in central Missouri. Of 83 nests initiated by our marked sample, most (81.9%) were located in edge habitats. Although continuous habitats were selected less as nest sites, the proportion of successful nests did not differ significantly from that in edge habitats. Our data indicate that continuous habitats should not be considered marginal nesting habitat. If the intensity of use and nest success that we observed are representative regionally or nationally, continuous habitats could contribute substantially to annual Mourning Dove production because of the high availability of these habitats throughout much of the Mourning Dove breeding range.

Un Banco de Pruebas Remoto para Experimentación en Robótica Ubicua

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Adrián Jiménez-González

2014-01-01

Full Text Available Resumen: La escasez de herramientas experimentales adecuadas ha sido señalada como un factor crítico en el desarrollo de la robótica ubícua. Este artículo describe un banco de pruebas remoto para experimentación en robótica ubicua integrando robots con redes inalámbricas de sensores. El banco de pruebas está compuesto por 5 robots Pioneer 3-AT, por una red de cámaras y por una red inalámbrica de sensores, todos ellos equipados con una amplia variedad de sensores. La arquitectura del banco de pruebas permite una gran diversidad de esquemas de cooperación entre sus elementos abstrayendo sus particularidades y capacidades sensoriales, computacionales y de comunicaciones. Permite ejecutar experimentos con distintos grados de descentralización. El banco de pruebas, instalado en la Escuela Técnica Superior de Ingeniería de la Universidad de Sevilla, es abierto y hace posible el acceso de forma remota mediante una interfaz gráfica intuitiva. Abstract: The lack of adequate experimental tools has been highligh- ted as a major critical issue in the development of ubiquitous ro- botics integrating mobile robots and wireless sensor networks. This paper describes a remotely operated testbed for ubiquitous robotics experimentation. It is currently comprised of 5 Pio- neer 3-AT robots, a camera network and a wireless sensor net- work WSN, each equipped with widespread off-the-shelf sen- sors. The testbed architecture allows wide variety of coopera- tion schemes among its elements, abstracting their particula- rities and sensory, computational and communication capabi- lities. It also allows performing experiments with different de- grees of decentralization. The testbed, currently deployed in the School of Engineering at the University of Seville, is open and can be accessed remotely through a friendly graphical user in- terface. Palabras clave: Bancos de pruebas, robótica ubicua, redes inalámbricas de sensores, Keywords: testbeds, networked

Construction patterns of birds’ nests provide insight into nest-building behaviours

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Lucia Biddle

2017-02-01

Full Text Available Previous studies have suggested that birds and mammals select materials needed for nest building based on their thermal or structural properties, although the amounts or properties of the materials used have been recorded for only a very small number of species. Some of the behaviours underlying the construction of nests can be indirectly determined by careful deconstruction of the structure and measurement of the biomechanical properties of the materials used. Here we examined this idea in an investigation of Bullfinch (Pyrrhula pyrrhula nests as a model for open-nesting songbird species that construct a “twig” nest, and tested the hypothesis that materials in different parts of nests serve different functions. The quantities of materials present in the nest base, sides and cup were recorded before structural analysis. Structural analysis showed that the base of the outer nests were composed of significantly thicker, stronger and more rigid materials compared to the side walls, which in turn were significantly thicker, stronger and more rigid than materials used in the cup. These results suggest that the placement of particular materials in nests may not be random, but further work is required to determine if the final structure of a nest accurately reflects the construction process.

Construction patterns of birds’ nests provide insight into nest-building behaviours

Science.gov (United States)

Goodman, Adrian M.

2017-01-01

Previous studies have suggested that birds and mammals select materials needed for nest building based on their thermal or structural properties, although the amounts or properties of the materials used have been recorded for only a very small number of species. Some of the behaviours underlying the construction of nests can be indirectly determined by careful deconstruction of the structure and measurement of the biomechanical properties of the materials used. Here we examined this idea in an investigation of Bullfinch (Pyrrhula pyrrhula) nests as a model for open-nesting songbird species that construct a “twig” nest, and tested the hypothesis that materials in different parts of nests serve different functions. The quantities of materials present in the nest base, sides and cup were recorded before structural analysis. Structural analysis showed that the base of the outer nests were composed of significantly thicker, stronger and more rigid materials compared to the side walls, which in turn were significantly thicker, stronger and more rigid than materials used in the cup. These results suggest that the placement of particular materials in nests may not be random, but further work is required to determine if the final structure of a nest accurately reflects the construction process. PMID:28265501

Construction patterns of birds' nests provide insight into nest-building behaviours.

Science.gov (United States)

Biddle, Lucia; Goodman, Adrian M; Deeming, D Charles

2017-01-01

Previous studies have suggested that birds and mammals select materials needed for nest building based on their thermal or structural properties, although the amounts or properties of the materials used have been recorded for only a very small number of species. Some of the behaviours underlying the construction of nests can be indirectly determined by careful deconstruction of the structure and measurement of the biomechanical properties of the materials used. Here we examined this idea in an investigation of Bullfinch ( Pyrrhula pyrrhula ) nests as a model for open-nesting songbird species that construct a "twig" nest, and tested the hypothesis that materials in different parts of nests serve different functions. The quantities of materials present in the nest base, sides and cup were recorded before structural analysis. Structural analysis showed that the base of the outer nests were composed of significantly thicker, stronger and more rigid materials compared to the side walls, which in turn were significantly thicker, stronger and more rigid than materials used in the cup. These results suggest that the placement of particular materials in nests may not be random, but further work is required to determine if the final structure of a nest accurately reflects the construction process.

Método para generar casos de prueba funcional en el desarrollo de software Generating functional testing case method in software development

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Liliana González Palacio

2009-07-01

Full Text Available Un aspecto crucial en el control de calidad del desarrollo de software son las pruebas y, dentro de estas, las pruebas funcionales, en las cuales se hace una verificación dinámica del comportamiento de un sistema, basada en la observación de un conjunto seleccionado de ejecuciones controladas o casos de prueba. Para hacer pruebas funcionales se requiere una planificación que consiste en definir los aspectos a chequear y la forma de verificar su correcto funcionamiento, punto en el cual adquieren sentido los casos de prueba. En este artículo derivado de investigación se define un método para generar casos de prueba funcional a partir de casos de uso del sistema, como producto intermedio del proyecto cofinanciado titulado "Herramienta para la documentación de pruebas funcionales"Testing is a main aspect in quality control of software development, especially functional tests. The aim of functional testing is to dynamically verify the system behavior, based on the observation of a given set of controlled executions or test cases. Planning is required to make functional tests, defining the aspects to be checked and the way to verify its proper operation; this allows test cases make sense. In this paper (research based, we propose a method to generate functional test cases from system use cases, based on the co-financed project "Tool for Documenting Functional Testing."

Validez de la prueba de adenosina deaminasa y del recuento diferencial de leucocitos para el diagnóstico de tuberculosis pleural

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Jhonatan Boris Quiñones-Silva

2010-03-01

Full Text Available Objetivo: Determinar la validez de la prueba de adenosina deaminasa (ADA y el recuento diferencial de leucocitos para el diagnóstico de tuberculosis pleural. Diseño: Estudio retrospectivo de precisión diagnóstica. Institución: Hospital Regional de Huacho, Ministerio de Salud, Huacho, Perú. Material: Historias clínicas de pacientes con prueba de ADA en líquido pleural. Intervenciones: Estudio de historias clínicas de pacientes a quienes se les realizó la prueba de ADA en líquido pleural, desde enero 2005 hasta diciembre 2007. El valor de la prueba de ADA y el recuento diferencial de leucocitos fueron analizados mediante la curva ROC. La sensibilidad (Se, especificidad (Sp, valores predictivos (VPP y VPN y los cocientes de verosimilitud (CVP y CVN fueron hallados para cada variable. Principales medidas de resultados: Punto de corte para la prueba de ADA para el diagnóstico de tuberculosis pleural. Resultados: La tuberculosis fue culpable de la mayoría de los derrames pleurales; 47,5 fue el punto de corte hallado para la prueba de ADA, con Se y Sp de 73% y 90%, respectivamente (IC 95%: 0,74 - 0,95; p72% incrementaría la sospecha de tuberculosis pleural.

Desarrollo de una prueba de comprensión audiovisual

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Casañ Núñez, Juan Carlos

2016-06-01

Full Text Available Este artículo forma parte de una investigación doctoral que estudia el uso de preguntas de comprensión audiovisual integradas en la imagen del vídeo como subtítulos y sincronizadas con los fragmentos de vídeo relevantes. Anteriormente se han publicado un marco teórico que describe esta técnica (Casañ Núñez, 2015b y un ejemplo en una secuencia didáctica (Casañ Núñez, 2015a. El presente trabajo detalla el proceso de planificación, diseño y experimentación de una prueba de comprensión audiovisual con dos variantes que será administrada junto con otros instrumentos en estudios cuasiexperimentales con grupos de control y tratamiento. Fundamentalmente, se pretende averiguar si la subtitulación de las preguntas facilita la comprensión, si aumenta el tiempo que los estudiantes miran en dirección a la pantalla y conocer la opinión del grupo de tratamiento sobre esta técnica. En la fase de experimentación se efectuaron seis estudios. En el último estudio piloto participaron cuarenta y un estudiantes de ELE (veintidós en el grupo de control y diecinueve en el de tratamiento. Las observaciones de los informantes durante la administración de la prueba y su posterior corrección sugirieron que las indicaciones sobre la estructura del test, las presentaciones de los textos de entrada, la explicación sobre el funcionamiento de las preguntas subtituladas para el grupo experimental y la redacción de los ítems resultaron comprensibles. Los datos de las dos variantes del instrumento se sometieron a sendos análisis de facilidad, discriminación, fiabilidad y descriptivos. También se calcularon las correlaciones entre los test y dos tareas de un examen de comprensión auditiva. Los resultados mostraron que las dos versiones de la prueba estaban preparadas para ser administradas.

Sorting it out: bedding particle size and nesting material processing method affect nest complexity.

Science.gov (United States)

Robinson-Junker, Amy; Morin, Amelia; Pritchett-Corning, Kathleen; Gaskill, Brianna N

2017-04-01

As part of routine husbandry, an increasing number of laboratory mice receive nesting material in addition to standard bedding material in their cages. Nesting material improves health outcomes and physiological performance in mice that receive it. Providing usable nesting material uniformly and efficiently to various strains of mice remains a challenge. The aim of this study was to determine how bedding particle size, method of nesting material delivery, and processing of the nesting material before delivery affected nest building in mice of strong (BALB/cAnNCrl) and weak (C3H/HeNCrl) gathering abilities. Our data suggest that processing nesting material through a grinder in conjunction with bedding material, although convenient for provision of bedding with nesting material 'built-in', negatively affects the integrity of the nesting material and subsequent nest-building outcomes. We also found that C3H mice, previously thought to be poor nest builders, built similarly scored nests to those of BALB/c mice when provided with unprocessed nesting material. This was true even when nesting material was mixed into the bedding substrate. We also observed that when nesting material was mixed into the bedding substrate, mice of both strains would sort their bedding by particle size more often than if it were not mixed in. Our findings support the utility of the practice of distributing nesting material mixed in with bedding substrate, but not that of processing the nesting material with the bedding in order to mix them.

Utilidad de la prueba torniquete en el diagnóstico diferencial de Dengue de otros síndromes febriles

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Claudia Ximena Méndez Duarte

2013-08-01

Full Text Available Introducción: El dengue es la infección transmitida por mosquitos más importante en el mundo. Siendo más susceptible a infectarse la población infantil. En la etapa inicial de la enfermedad los síntomas son indiferenciables de otros síndromes febriles agudos, situación que hace complejo, tardío y poco sensible el diagnóstico clínico en la fase aguda de la enfermedad. La prueba torniquete es utilizada como un criterio de clasificación para definir la severidad del dengue hemorrágico por la Organización Mundial de la Salud, podría utilizarse en el diagnóstico diferencial del dengue. Objetivo: Evaluar en población infantil las características operativas de la prueba torniquete en el diagnóstico diferencial del dengue de otros síndromes febriles agudos. Métodos: Entre junio de 2006 y Abril del 2008 se incluyeron del servicio de urgencias pacientes entre dos y 12 años de edad que presentaban un cuadro febril sin origen aparente. Se les realizó un examen físico estandarizado junto con la prueba de torniquete, calculándose la sensibilidad, especificidad, valor predictivo positivo (VPP y negativo (VPN a la prueba. Resultados: Se captaron 129 pacientes y se diagnosticaron 66 casos de dengue. La prueba torniquete tuvo sensibilidad de 60.6% (IC95%=48.8-72.4, especificidad 55.9% (IC95%=43.3-68.6, VPP 60.6% (IC95%=48.8-72.4 y un VPN 55.9%. (IC95%=43.3-68.6. El resultado de la prueba estuvo asociado al tiempo de tolerancia del torniquete (p<0.001. Conclusiones: La prueba torniquete por sí sola no es útil como herramienta clínica para diferenciar el dengue de otros síndromes febriles en niños entre los dos y los 12 años de zonas endémicas.

Prueba de la hipótesis de comportamiento colusivo entre los miembros de la OPEP

OpenAIRE

Antonio Spilimbergo

1995-01-01

(Disponible en idioma inglés únicamente) En este trabajo se presenta una prueba para distinguir entre los comportamientos de los productores de recursos agotables. El comportamiento de un productor competitivo de un recurso agotable debería cumplir con la ecuación de Euler. La existencia de mercados de futuros nos permite dejar de lado los aspectos difíciles que tienen que ver con el cálculo de los precios y la demanda futuros. Este marco teórico se emplea para poner a prueba la hipótesis de ...

Preferencias y satisfacción hacia un programa de tamizaje con pruebas autoadministradas de detección del virus de papiloma humano

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Flavia Morán

Full Text Available Estudio transversal que describe preferencias y satisfacción hacia un programa de tamizaje de cáncer cervical con pruebas rápidas autoadministradas, para la detección del virus de papiloma humano (VPH. De las 2090 usuarias captadas por el programa en Ventanilla Callao-Perú, se seleccionó aleatoriamente a 97 para ser encuestadas. Asimismo, se realizaron entrevistas a mujeres líderes de la comunidad, encargadas de ofrecer las pruebas. El 74,2% de las usuarias se sintió, cuanto menos, satisfecha con el programa. El 68% de las mujeres prefiere la autotoma de la prueba, principalmente por demandar menos tiempo. De las mujeres que prefieren la toma en el centro de salud, el 90,3% lo hace por la seguridad de que la prueba sea realizada correctamente. La inclusión de líderes comunitarias en el programa permitió una buena difusión de la prueba y de los pasos para realizarla.

SIMULACIÓN DE PRUEBAS DE CARGA EN PILOTES USANDO UN MODELO CONSTITUTIVO HIPOPLÁSTICO

Directory of Open Access Journals (Sweden)

Juan Carlos Ruge Cárdenas

Full Text Available La presente investigación tuvo como objetivo principal, simular mediante el empleo de un programa basado en el método de elementos finitos, los resultados obtenidos de pruebas de carga en pilotes individuales fundados en arcillas porosas de Brasilia DF (Brasil, las cuales poseen características metaestables. Para las simulaciones se empleó la ecuación constitutiva hipoplástica. Los parámetros del suelo fueron obtenidos por medio de ensayos de laboratorio que permitieron estimar propiedades geotécnicas del suelo, así como parámetros de resistencia, deformabilidad e identificación estratigráfica. Como conclusión general se reporta que la predicción aportada por el modelo hipoplástico en relación a las pruebas de carga en el tramo antes de la ruptura es aceptable, sin embargo debido a la pérdida de adhesión en la interface suelo-pilote en el momento de la prueba, se nota la incapacidad del modelo para simular este efecto de manera adecuada, ya que existen condiciones de metaestabilidad y de parcial saturación presentes en el problema geotécnico.

Pre-nesting and nesting behavior of the Swainson's warbler

Science.gov (United States)

Meanley, B.

1969-01-01

The Swainson?s Warbler is one of the least known of southern birds. Although fairly common in some parts of its summer range, observations of its breeding biology have been made by very few persons. The present study was conducted mostly at Macon, Georgia; Pendleton Ferry, Arkansas; and Dismal Swamp, Virginia....In central Georgia and east-central Arkansas, Swainson?s Warblers usually arrive on their territories during the first two weeks in April. Territories in several localities ranged in size from 0.3 to 4.8 acres. A color-marked Arkansas male occupied the same territory for at least four months. Hostile encounters between territorial male Swainson?s Warblers usually take place along the boundary of adjacent territories. Paired males were more aggressive than unpaired males. Toward the end of an encounter one of the two males would usually perform a display in which the wing and tail feathers were spread and the tail vibrated. Following boundary encounters males drifted back onto their territories and usually sang unbroken courses of songs for several minutes.....During pre-nesting at Macon, a mated pair spent the day mostly on the ground within 20 feet of each other, often foragin g 3 to 4 feet apart. What may have been a form of courtship display, in which the male flew from a perch down to the female and either pecked her rump or pounced on her, occurred about three times each hour throughout the day. During this period the male sang less than at other times during the breeding season.....First nests are usually built by the first week in May. Although other investigators reported finding nests of this species outside of the defended territory, all nests that I have found were within the territory. The large, bulky nest of this species usually is placed 2-6 feet above the ground. It is built by the female from materials gathered close to the nest site; and takes two or three days to complete.....Three and occasionally four white eggs are laid. The female

Open cup nests evolved from roofed nests in the early passerines.

Science.gov (United States)

Price, J Jordan; Griffith, Simon C

2017-02-08

The architectural diversity of nests in the passerine birds (order Passeriformes) is thought to have played an important role in the adaptive radiation of this group, which now comprises more than half of avian species and occupies nearly all terrestrial ecosystems. Here, we present an extensive survey and ancestral state reconstruction of nest design across the passerines, focusing on early Australian lineages and including members of nearly all passerine families worldwide. Most passerines build open cup-shaped nests, whereas a minority build more elaborate domed structures with roofs. We provide strong evidence that, despite their relative rarity today, domed nests were constructed by the common ancestor of all modern passerines. Open cup nests evolved from enclosed domes at least four times independently during early passerine evolution, at least three of which occurred on the Australian continent, yielding several primarily cup-nesting clades that are now widespread and numerically dominant among passerines. Our results show that the ubiquitous and relatively simple cup-shaped nests of many birds today evolved multiple times convergently, suggesting adaptive benefits over earlier roofed designs. © 2017 The Author(s).

Do Predation Rates on Artificial Nests Accurately Reflect Predation Rates on Natural Bird Nests?

Science.gov (United States)

David I. King; Richard M. DeGraaf; Curtice R. Griffin; Thomas J. Maier

1999-01-01

Artificial nests are widely used in avian field studies. However, it is unclear how well predation rates on artificial nests reflect predation rates on natural nests. Therefore, we compared survival rates of artificial nests (unused natural nests baited with House Sparrow eggs) with survival rates of active bird nests in the same habitat at the same sites. Survival...

Nest structure and communal nesting in Euglossa (Glossura annectans Dressler (Hymenoptera, Apidae, Euglossini

Directory of Open Access Journals (Sweden)

Carlos Alberto Garófalo

1998-01-01

Full Text Available Three nests of Euglossa (Glossura annectans Dressier, 1982 were obtained from trap nests at Serra do Japi, Jundiai, São Paulo State, Brazil. The bees nested in bamboo cane (one nest and in wooden-boxes (two nests. Solitary (two cases and pleometrotic (one case foundations were observed. Two nests were re-used once by two females working in each of them. Re-using females that shared the nests were of the same generation and each built, provisioned and oviposited in her own cells, characterizing a communal association. The brood development period was related to climatic conditions. Natural enemies included Anthrax oedipus oedipus Fabricius, 1805 (Bombyliidae, Coelioxys sp. (Megachilidae and Melittobia sp. (Eulophidae.

Effect of heterogeneity of nest boxes on occurrence of gregarious nesting in laying hens

DEFF Research Database (Denmark)

Clausen, Tina; Riber, Anja Brinch

2012-01-01

Gregarious nesting, where hens select already occupied nest boxes even when other nest boxes are unoccupied, is an unwanted behaviour in laying hens that may reduce animal welfare and pose a financial cost to the producer. It has been suggested that gregarious nesting is caused by the difficulties...... nesting was higher in experimental groups compared to control groups (P right were higher compared to nest boxes positioned...

Efecto de la categoría de edad y reglamento en las marcas y puntuación de las pruebas combinadas

OpenAIRE

Paz, Patricia; Palao Andrés, José Manuel

2015-01-01

El objetivo de este estudio fue conocer como las marcas y la puntuación en pruebas combinadas en atletismo varían en función de la categoría de edad y del reglamento (pruebas y tablas de puntuación). La muestra del estudio fueron 1650 participaciones en pruebas combinadas (790 masculinas y 860 femeninas) de los 15 mejores atletas del ranking desde la temporada 1998-1999 hasta la temporada 2008-2009, ambas inclusive, de las categorías infantil hasta absoluta. Las variables de estudio fueron: m...

Nest predation increases with parental activity: separating nest site and parental activity effects.

OpenAIRE

Martin, T E; Scott, J; Menge, C

2000-01-01

Alexander Skutch hypothesized that increased parental activity can increase the risk of nest predation. We tested this hypothesis using ten open-nesting bird species in Arizona, USA. Parental activity was greater during the nestling than incubation stage because parents visited the nest frequently to feed their young during the nestling stage. However, nest predation did not generally increase with parental activity between nesting stages across the ten study species. Previous investigators h...

Análisis sobre la ponderación de la prueba en el sistema electoral chileno

Directory of Open Access Journals (Sweden)

Carlos Manuel Rosales García

2013-01-01

Full Text Available El Tribunal Calificador de Elecciones chileno tiene la facultad constitucional de erigirse como jurado para la valoración de las pruebas, esto significa poder apreciar la prueba de manera libre, para posteriormente, sentenciar con arreglo a derecho. Este artículo estudiará las principales características del juicio por jurado, con base en la doctrina y experiencia del derecho estadounidense, observando tanto su adopción y adaptación por el Tribunal Electoral, así como sus pros y contras en el sistema electoral chileno

The nest as fortress: Defensive behavior of Polybia emaciata, a mud-nesting eusocial wasp

Directory of Open Access Journals (Sweden)

Sean O'Donnell

2002-02-01

Full Text Available The swarm-founding wasp Polybia emaciata is unusual among eusocial Vespidae because it uses mud, rather than wood pulp, as its primary nest construction material. Polybia emaciata nests are more durable than similarly sized paper nests. We tested the hypothesis that the defensive behavior of this wasp may have been modified to take advantage of their strong nests in defense against vertebrate attacks. We simulated vertebrate disturbances by tapping on, and breathing in, P. emaciata. nests and similarly sized P. occidentalis paper nests in the same location at the same time. Polybia emaciata. responses to disturbance were qualitatively different from those of P. occidentalis. The latter exit the nest and attack, while P. emaciata. workers typically fled or entered the nest, attacking only after repeated and extended disturbances. We conclude that durable nest material may permit predator avoidance behavior in P. emaciata.. We compare the defensive responses of P. emaciata. workers with those of other swarm-founding Vespidae, and discuss several selective forces that could cause the evolution of species variation in nest defense behavior.

Cavity Nesting Birds

Science.gov (United States)

Virgil E. Scott; Keith E. Evans; David R. Patton; Charles P. Stone

1977-01-01

Many species of cavity-nesting birds have declined because of habitat reduction. In the eastern United States, where primeval forests are gone, purple martins depend almost entirely on man-made nesting structures (Allen and Nice 1952). The hole-nesting population of peregrine falcons disappeared with the felling of the giant trees upon which they depended (Hickey and...

Nest predators of open and cavity nesting birds in oak woodlands

Science.gov (United States)

Kathryn L. Purcell; Jared Verner

1999-01-01

Camera setups revealed at least three species of rodents and seven species of birds as potential predators at artificial open nests. Surprisingly, among avian predators identified at open nests, one third were Bullock's Orioles (Icterus bullockii). Two rodent species and three bird species were potential predators at artificial cavity nests. This high predator...

Las pruebas de integración como proceso de la calidad del software en el ámbito de las telecomunicaciones

OpenAIRE

Gómez Rodríguez, Nuria

2015-01-01

Para explicar la idea y la filosofía de la realización de pruebas, emplearé una metodología de pruebas que teorice los principios, aporte definiciones e instrumentos para modelar un plan de pruebas. Esta idea está basada en la certificación ISTQB en la que estoy titulada y que sin duda, será el apoyo teórico a este proyecto. Además, partiré de una base teórica imprescindible, se trata del libro de Roger S. Pressman titulado "Ingeniería del Software - Un enfoque práctico" que trata sobre la in...

Sistema automatizado para la realización de pruebas funcionales a las protecciones electrónicas CELCOR

Directory of Open Access Journals (Sweden)

Rodolfo García Bermúdez

2006-01-01

Full Text Available Se realiza el diseño e implementación de un sistema automatizado que permite hacer las pruebas funcionales a las protecciones electrónicas por sobrecorriente para equipos de refrigeración producidas en el Laboratorio Científico Productivo perteneciente a la Universidad de Holguín "Oscar Lucero Moya". Para ello se realizó un estudio de las especificaciones funcionales que reclama el fabricante de las protecciones, que hizo posible definir un grupo de pruebas que verifican dichas especificaciones, se emplean módulos de adquisición de datos conectados por medio de una interfaz RS485 a la computadora y se hizo el diseño de la electrónica necesaria para la adaptación de las señales a estos módulos. El sistema informático permite realizar las pruebas a seis protecciones al mismo tiempo, cuyos resultados son almacenados en una base de datos. Adicionalmente puede realizarse la caracterización de los transformadores de corriente utilizados como sensores en las protecciones. El sistema realiza un grupo de pruebas que son imposibles de forma manual, eleva la productividad de los técnicos, disminuye los costos asociados al consumo de electricidad y permite que al 100% de las protecciones que salen al mercado se le verifiquen todas sus especificaciones funcionales.

Modeling nest survival of cavity-nesting birds in relation to postfire salvage logging

Science.gov (United States)

Vicki Saab; Robin E. Russell; Jay Rotella; Jonathan G. Dudley

2011-01-01

Salvage logging practices in recently burned forests often have direct effects on species associated with dead trees, particularly cavity-nesting birds. As such, evaluation of postfire management practices on nest survival rates of cavity nesters is necessary for determining conservation strategies. We monitored 1,797 nests of 6 cavity-nesting bird species: Lewis'...

Triangular Nests!

Science.gov (United States)

Powell, R. I.

2002-01-01

Shows how integer-sided triangles can be nested, each nest having a single enclosing isosceles triangle. Brings to light what can be seen as a relatively simple generalization of Pythagoras' theorem, a result that should be readily accessible to many secondary school pupils. (Author/KHR)

Nest-site habitat of cavity-nesting birds at the San Joaquin Experimental Range

Science.gov (United States)

Kathryn L. Purcell; Jared. Verner

2008-01-01

Detailed information about the nesting habitats of birds, including those needed for successful nesting, can provide a better understanding of the ecological factors that permit coexistence of different species and may aid in conservation efforts. From 1989 through 1994, we studied the nesting habitat of secondary cavity-nesting birds in oak woodlands at the San...

Spawning chronology, nest site selection and nest success of smallmouth bass during benign streamflow conditions

Science.gov (United States)

Dauwalter, D.C.; Fisher, W.L.

2007-01-01

We documented the nesting chronology, nest site selection and nest success of smallmouth bass Micropterus dolomieu in an upstream (4th order) and downstream (5th order) reach of Baron Fork Creek, Oklahoma. Males started nesting in mid-Apr. when water temperatures increased to 16.9 C upstream, and in late-Apr. when temperatures increased to 16.2 C downstream. Streamflows were low (77% upstream to 82% downstream of mean Apr. streamflow, and 12 and 18% of meanjun. streamflow; 47 and 55 y of record), and decreased throughout the spawning period. Larger males nested first upstream, as has been observed in other populations, but not downstream. Upstream, progeny in 62 of 153 nests developed to swim-up stage. Downstream, progeny in 31 of 73 nests developed to swim-up. Nesting densities upstream (147/km) and downstream (100/km) were both higher than any densities previously reported. Males selected nest sites with intermediate water depths, low water velocity and near cover, behavior that is typical of smallmouth bass. Documented nest failures resulted from human disturbance, angling, and longear sunfish predation. Logistic exposure models showed that water velocity at the nest was negatively related and length of the guarding male was positively related to nest success upstream. Male length and number of degree days were both positively related to nest success downstream. Our results, and those of other studies, suggest that biological factors account for most nest failures during benign (stable, low flow) streamflow conditions, whereas nest failures attributed to substrate mobility or nest abandonment dominate when harsh streamflow conditions (spring floods) coincide with the spawning season.

Cavity-nesting bird use of nest boxes in vineyards of central-coast California

Science.gov (United States)

Daniel P. Mummert; Laura Baines; William D. Tietje

2002-01-01

Oak woodland habitat is being degraded or replaced by vineyards in many areas of central-coastal California. Oak woodlands are home to many insectivorous, cavity-nesting birds that would be beneficial in and around vineyards. During March to June 2001, we used bluebird nest boxes to study nest box use and productivity of cavity-nesting birds in vineyards versus...

Livestock grazing and trampling of birds' nests: An experiment using artificial nests

OpenAIRE

Mandema, Freek S.; Tinbergen, Joost M.; Ens, Bruno J.; Bakker, Jan P.

2013-01-01

The purpose of this study is to experimentally determine the differences between four grazing treatments on the trampling of nests. Additionally, we examine to what extent the trampling probability of nests is higher close to a source of fresh water. We compare the trampling of artificial nests in five different grazing treatments in an experimental design. We use buried clay pigeon targets as artificial mimics of bird nests to obtain reliable estimates of trampling risk and compare these wit...

Flown The Nest

OpenAIRE

Sebbane, Nathalie

2012-01-01

Lorsque le quotidien régional, The Champion, commence à publier Flown The Nest en 1972 sous forme d’épisodes, Bird’s Nest Soup est déjà en vente, et la troisième partie de l’autobiographie d’Hanna, Housekeeper At Large, est sous presse. L’édition de 2009 contient Flown The Nest et Housekeeper at Large. Dans Bird’s Nest Soup, Hanna Greally racontait les dix-huit années de sa vie passées au sein d’un hôpital psychiatrique. Les raisons pour lesquelles elle y avait été enfermée, à la demande de s...

From neurons to nests: nest-building behaviour as a model in behavioural and comparative neuroscience.

Science.gov (United States)

Hall, Zachary J; Meddle, Simone L; Healy, Susan D

Despite centuries of observing the nest building of most extant bird species, we know surprisingly little about how birds build nests and, specifically, how the avian brain controls nest building. Here, we argue that nest building in birds may be a useful model behaviour in which to study how the brain controls behaviour. Specifically, we argue that nest building as a behavioural model provides a unique opportunity to study not only the mechanisms through which the brain controls behaviour within individuals of a single species but also how evolution may have shaped the brain to produce interspecific variation in nest-building behaviour. In this review, we outline the questions in both behavioural and comparative neuroscience that nest building could be used to address, summarize recent findings regarding the neurobiology of nest building in lab-reared zebra finches and across species building different nest structures, and suggest some future directions for the neurobiology of nest building.

Eficacia de la Prueba del Cuy en el Diagnóstico de Patologia Vesicular en Pacientes del Consultorio Particular, Arequipa. 2007 - 2008

OpenAIRE

Zeballos Benavides María Candelaria

2010-01-01

En la investigación se trata de encontrar los hallazgos en la vesícula de la persona con la Prueba del Cuy y compararlos con los hallazgos de la Prueba Ecográfica para determinar su eficacia. El objetivo del presente estudio de investigación fue evaluar la Eficacia de la Prueba del Cuy (cobayo), en el diagnóstico de Patología Vesicular. Se escogió un grupo de estudio que fue constituido por 21 personas con sintomatología aparentemente vesicular, deseosos de encontrar resp...

Avoiding the nest : responses of field sparrows to the threat of nest predation

Science.gov (United States)

Dirk E. Burhans

2000-01-01

Nest predation is a major source of reproductive failure in birds (Ricklefs 1969, Martin 1992). Birds confronted with an enemy near the nest may use behaviors to deter the prospect of nest predation. The benefits of nest defense have been shown for many agressive species (Martin 1992), but smaller birds that cannot deter predators may need to resort to other behaviors...

Evaluando los conocimientos previos de los alumnos a través de pruebas objetivas: ¿opción múltiple o test de lagunas?

Directory of Open Access Journals (Sweden)

Lucha Cuadros, Rosa M.

2011-03-01

Full Text Available En los test utilizados para comprobar los conocimientos previos de los alumnos y conocer sus necesidades, se suele utilizar pruebas indirectas tipo opción múltiple. ¿Son este tipo de pruebas las más adecuadas para evaluar los conocimientos de los estudiantes? Para dilucidar esta cuestión, hemos analizado los resultados de dos tipos de pruebas indirectas evaluadas objetivamente: el test de opción múltiple y el test de lagunas. En la discusión de los resultados se analizan las implicaciones pedagógicas que la elección del tipo de prueba ofrece tanto para el profesor como para el alumno.

Using Artificial Nests to Study Nest Predation in Birds

Science.gov (United States)

Belthoff, James R.

2005-01-01

A simple and effective field exercise that demonstrates factors affecting predation on bird nests is described. With instructor guidance, students in high school biology or college-level biology, ecology, animal behavior, wildlife management or ornithology laboratory courses can collaborate to design field experiments related to nest depredation.

Efectos de los rangos de movimientos y tiempos de descanso sobre la prueba de 1 RM

OpenAIRE

Barrantes Segura, Ariel; Aragón Vargas, Luis Fernando

2014-01-01

Este informe de investigación fue publicado como póster en Medicine and Science in Sports and Exercise 46(5):s192, 10.1249/01.mss.0000493922.19651.52, issn:1530-0315, issn:0195-9131 Los resultados de las pruebas de fuerza de 1RM varían para el mismo ejercicio en función del rango de movimiento (RDM) que se utiliza. El reposo insuficiente entre intentos también puede perjudicar el rendimiento en la prueba. OBJETIVO: determinar el efecto del rango de movimiento y el tiempo de recuperación en...

Livestock grazing and trampling of birds' nests : An experiment using artificial nests

NARCIS (Netherlands)

Mandema, Freek S.; Tinbergen, Joost M.; Ens, Bruno J.; Bakker, Jan P.

The purpose of this study is to experimentally determine the differences between four grazing treatments on the trampling of nests. Additionally, we examine to what extent the trampling probability of nests is higher close to a source of fresh water. We compare the trampling of artificial nests in

Nested and Hierarchical Archimax copulas

KAUST Repository

Hofert, Marius

2017-07-03

The class of Archimax copulas is generalized to nested and hierarchical Archimax copulas in several ways. First, nested extreme-value copulas or nested stable tail dependence functions are introduced to construct nested Archimax copulas based on a single frailty variable. Second, a hierarchical construction of d-norm generators is presented to construct hierarchical stable tail dependence functions and thus hierarchical extreme-value copulas. Moreover, one can, by itself or additionally, introduce nested frailties to extend Archimax copulas to nested Archimax copulas in a similar way as nested Archimedean copulas extend Archimedean copulas. Further results include a general formula for the density of Archimax copulas.

Nested and Hierarchical Archimax copulas

KAUST Repository

Hofert, Marius; Huser, Raphaë l; Prasad, Avinash

2017-01-01

The class of Archimax copulas is generalized to nested and hierarchical Archimax copulas in several ways. First, nested extreme-value copulas or nested stable tail dependence functions are introduced to construct nested Archimax copulas based on a single frailty variable. Second, a hierarchical construction of d-norm generators is presented to construct hierarchical stable tail dependence functions and thus hierarchical extreme-value copulas. Moreover, one can, by itself or additionally, introduce nested frailties to extend Archimax copulas to nested Archimax copulas in a similar way as nested Archimedean copulas extend Archimedean copulas. Further results include a general formula for the density of Archimax copulas.

Nest site characteristics, nesting movements, and lack of long-term nest site fidelity in Agassiz's desert tortoises at a wind energy facility in southern California

Science.gov (United States)

Lovich, Jeffrey E.; Agha, Mickey; Yackulic, Charles B.; Meyer-Wilkins, Kathie; Bjurlin, Curtis; Ennen, Joshua R.; Arundel, Terry R.; Austin, Meaghan

2014-01-01

Nest site selection has important consequences for maternal and offspring survival and fitness. Females of some species return to the same nesting areas year after year. We studied nest site characteristics, fidelity, and daily pre-nesting movements in a population of Agassiz’s desert tortoises (Gopherus agassizii) at a wind energy facility in southern California during two field seasons separated by over a decade. No females returned to the same exact nest site within or between years but several nested in the same general area. However, distances between first and second clutches within a year (2000) were not significantly different from distances between nests among years (2000 and 2011) for a small sample of females, suggesting some degree of fidelity within their normal activity areas. Environmental attributes of nest sites did not differ significantly among females but did among years due largely to changes in perennial plant structure as a result of multiple fires. Daily pre-nesting distances moved by females decreased consistently from the time shelled eggs were first visible in X-radiographs until oviposition, again suggesting some degree of nest site selection. Tortoises appear to select nest sites that are within their long-term activity areas, inside the climate-moderated confines of one of their self-constructed burrows, and specifically, at a depth in the burrow that minimizes exposure of eggs and embryos to lethal incubation temperatures. Nesting in “climate-controlled” burrows and nest guarding by females relaxes some of the constraints that drive nest site selection in other oviparous species.

Nest site attributes and temporal patterns of northern flicker nest loss: effects of predation and competition.

Science.gov (United States)

Fisher, Ryan J; Wiebe, Karen L

2006-04-01

To date, most studies of nest site selection have failed to take into account more than one source of nest loss (or have combined all sources in one analysis) when examining nest site characteristics, leaving us with an incomplete understanding of the potential trade-offs that individuals may face when selecting a nest site. Our objectives were to determine whether northern flickers (Colaptes auratus) may experience a trade-off in nest site selection in response to mammalian nest predation and nest loss to a cavity nest competitor (European starling, Sturnus vulgaris). We also document within-season temporal patterns of these two sources of nest loss with the hypothesis that flickers may also be constrained in the timing of reproduction under both predatory and competitive influence. Mammalian predators frequently depredated flicker nests that were: lower to the ground, less concealed by vegetation around the cavity entrance and at the base of the nest tree, closer to coniferous forest edges and in forest clumps with a high percentage of conifer content. Proximity to coniferous edges or coniferous trees increased the probability of nest predation, but nests near conifers were less likely to be lost to starlings. Flickers may thus face a trade-off in nest site selection with respect to safety from predators or competitors. Models suggested that peaks of nest predation and nest loss to eviction occurred at the same time, although a competing model suggested that the peak of nest loss to starlings occurred 5 days earlier than the peak of mammalian predation. Differences in peaks of mammalian predation and loss to starlings may constrain any adjustment in clutch initiation date by flickers to avoid one source of nest loss.

Relaciones entre pruebas de velocidad, tests de salto y dinamometría isométrica en velocistas

Directory of Open Access Journals (Sweden)

Rafael Sabido Solana

2010-09-01

Full Text Available Dentro de las habilidades deportivas, la capacidad de producir fuerza lo más rápidamente posible, o fuerza explosiva, juega el papel más importante en la optimización de dichas habilidades. Zatsiorsky (1995 la define como “la habilidad para desarrollar la máxima fuerza en la menor cantidad de tiempo”. Las correlaciones existentes entre pruebas de velocidad y tests de salto han sido ampliamente observadas. Sin embargo, las correlaciones entre pruebas de velocidad y tests isométricos están menos estudiadas. Una muestra de 24 velocistas de categoría junior fue sometida a pruebas de velocidad específica, tests de salto con contramovimiento y en profundidad, así como a un test isométrico máximo para la musculatura extensora del tobillo. Los resultados muestran fuertes relaciones entre los tests de carrera y los de salto, así como de estos últimos con los de dinamometría. Por otro lado, sólo con el test de 20 metros se obtienen correlaciones con variables del test isométrico, sin que se encuentren correlaciones con la marca en 100 metros lisos. La principal conclusión de nuestros datos es que las variables medidas en un test isométrico van a tener alta relación con la primera fase de la carrera en pruebas de velocidad.

Nest marking behavior and chemical composition of olfactory cues involved in nest recognition in Megachile rotundata.

Science.gov (United States)

Guédot, Christelle; Buckner, James S; Hagen, Marcia M; Bosch, Jordi; Kemp, William P; Pitts-Singer, Theresa L

2013-08-01

In-nest observations of the solitary bee, Megachile rotundata (F.), revealed that nesting females apply olfactory cues to nests for nest recognition. On their way in and out of the nest, females drag the abdomen along the entire length of the nest, and sometimes deposit fluid droplets from the tip of the abdomen. The removal of bee-marked sections of the nest resulted in hesitation and searching behavior by females, indicating the loss of olfactory cues used for nest recognition. Chemical analysis of female cuticles and the deposits inside marked nesting tubes revealed the presence of hydrocarbons, wax esters, fatty aldehydes, and fatty alcohol acetate esters. Chemical compositions were similar across tube samples, but proportionally different from cuticular extracts. These findings reveal the importance of lipids as chemical signals for nest recognition and suggest that the nest-marking cues are derived from a source in addition to, or other than, the female cuticle.

Buteo Nesting Ecology: Evaluating Nesting of Swainson's Hawks in the Northern Great Plains.

Science.gov (United States)

Inselman, Will M; Datta, Shubham; Jenks, Jonathan A; Jensen, Kent C; Grovenburg, Troy W

2015-01-01

Swainson's hawks (Buteo swainsoni) are long-distance migratory raptors that nest primarily in isolated trees located in areas of high grassland density. In recent years, anthropogenic conversion of grassland habitat has raised concerns about the status of the breeding population in the northern Great Plains. In 2013, we initiated a study to investigate the influence of extrinsic factors influencing Swainson's hawk nesting ecology in north-central South Dakota and south-central North Dakota. Using ground and aerial surveys, we located and monitored nesting Swainson's hawk pairs: 73 in 2013 and 120 in 2014. We documented 98 successful breeding attempts that fledged 163 chicks; 1.52 and 1.72 fledglings per successful nest in 2013 and 2014, respectively. We used Program MARK to evaluate the influence of land cover on nest survival. The top model, SDist2Farm+%Hay, indicated that nest survival (fledging at least one chick) decreased as nests were located farther from farm sites and as the percent of hay cover increased within 1200-m of the nest site (34.4%; 95% CI = 27.6%-42.3%). We used logistic regression analysis to evaluate the influence of landscape variables on nest-site selection; Swainson's hawks selected for nest sites located closer to roads. We suggest that tree belts associated with farm sites, whether occupied or not, provide critical breeding sites for Swainson's hawks. Additionally, poor breeding success may be related to the late migratory behavior of this species which requires them to occupy marginal habitat due to other raptors occupying the most suitable habitat prior to Swainson's hawks arriving to the breeding grounds.

La prueba obtenida mediante coacción y su inadmisibilidad ante la Corte Interamericana de Derechos Humanos

OpenAIRE

Paúl Díaz, Álvaro

2016-01-01

La Corte Interamericana de Derechos Humanos efectúa un amplio análisis probatorio para determinar la ocurrencia de violaciones de derechos humanos. Ella tiende a ser muy flexible con la admisión de la prueba, sin perjuicio de ello estaría obligada a excluir confesiones obtenidas mediante coacción. En relación con esto, la Corte ha hecho afirmaciones que parecen propiciar la exclusión de toda prueba obtenida mediante coerción, y dar pie a la doctrina del fruto de árbol envenenado. Este artícul...

FACTORES ASOCIADOS A LA REALIZACIÓN DE UNA PRUEBA DE DETECCIÓN DE VIH EN ESTUDIANTES UNIVERSITARIOS.

Directory of Open Access Journals (Sweden)

Cindy Alcarraz

2012-02-01

Full Text Available Objetivo: Determinar factores asociados a la realización de la prueba de detección de infección por VIH en estudiantes de la Universidad Nacional Mayor San Marcos (UNMSM. Diseño: Estudio transversal. Lugar: Campus Universitario, Facultad de Medicina Veterinaria, Facultad de Medicina. Participantes: Estudiantes regulares de pregrado de la UNMSM en el periodo 2008-I. Intervenciones: Cuestionario estructurado de 63 ítems, realizándose un muestreo no probabilístico por conveniencia. Se aplicaron los programas SPSS v.15.0 para Windows® y EpiDat v.3.1. Principales medidas de resultados: Frecuencias de las variables de estudio y Odds Ratio con IC al 95%. Resultados: Se encuestó a 368 estudiantes (59,3% varones y 40,7% mujeres. El 54,4% ya había iniciado su vida sexual; 49,5% de éstos, antes de los 18 años. Sólo 33 (9% afirmaron haberse realizado anteriormente una prueba de detección de infección por VIH, mientras que 310 (84,2% la consideraron necesaria. Los hombres mostraron mayor probabilidad de someterse a la prueba diagnóstica de infección por VIH en comparación a las mujeres (OR: 2.77, IC 95%: 1.17-6.55. Se encontró relación con el hecho de haberse sometido anteriormente a la prueba de VIH, en aquellos que ya han iniciado su vida sexual y en los que han tenido 5 o más parejas sexuales (OR: 3.44, IC 95%: 1.45-8.14; OR: 3.03, IC 95%: 1.14-8.09, en comparación a los que aún no han tenido relaciones sexuales, y a los que han tenido 1 o 2 parejas, respectivamente. Conclusión: Los factores que se asociaron a mayor probabilidad de realizarse la prueba de VIH fueron la vida sexual activa y el número elevado de parejas sexuales.

Sharp-Tailed Grouse Nest Survival and Nest Predator Habitat Use in North Dakota's Bakken Oil Field.

Directory of Open Access Journals (Sweden)

Paul C Burr

Full Text Available Recent advancements in extraction technologies have resulted in rapid increases of gas and oil development across the United States and specifically in western North Dakota. This expansion of energy development has unknown influences on local wildlife populations and the ecological interactions within and among species. Our objectives for this study were to evaluate nest success and nest predator dynamics of sharp-tailed grouse (Tympanuchus phasianellus in two study sites that represented areas of high and low energy development intensities in North Dakota. During the summers of 2012 and 2013, we monitored 163 grouse nests using radio telemetry. Of these, 90 nests also were monitored using miniature cameras to accurately determine nest fates and identify nest predators. We simultaneously conducted predator surveys using camera scent stations and occupancy modeling to estimate nest predator occurrence at each site. American badgers (Taxidea taxus and striped skunks (Mephitis mephitis were the primary nest predators, accounting for 56.7% of all video recorded nest depredations. Nests in our high intensity gas and oil area were 1.95 times more likely to succeed compared to our minimal intensity area. Camera monitored nests were 2.03 times more likely to succeed than non-camera monitored nests. Occupancy of mammalian nest predators was 6.9 times more likely in our study area of minimal gas and oil intensity compared to the high intensity area. Although only a correlative study, our results suggest energy development may alter the predator community, thereby increasing nest success for sharp-tailed grouse in areas of intense development, while adjacent areas may have increased predator occurrence and reduced nest success. Our study illustrates the potential influences of energy development on the nest predator-prey dynamics of sharp-tailed grouse in western North Dakota and the complexity of evaluating such impacts on wildlife.

Hawaii ESI: NESTS (Nest Points)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for seabird nesting colonies in coastal Hawaii. Vector points in this data set represent locations of...

Maryland ESI: NESTS (Nest Points)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for raptors in Maryland. Vector points in this data set represent bird nesting sites. Species-specific...

Biomechanical testing of materials in avian nests provides insight into nest construction behaviour

OpenAIRE

Biddle, Lucia E.; Deeming, D. Charles; Goodman, Adrian M.

2015-01-01

Animals that use materials to build nest structures have long since fascinated biologists and engineers alike. Avian nests are generally composed of collected materials brought together into a cup-like structure in which the bird sits to incubate eggs and, in many cases, it is where chicks are reared. Hence, the materials in a nest can be presumed to be loaded in compression, but relatively few studies have investigated the mechanical role of the nest elements and their position w...

Nesting biology of Trypoxylon (Trypargilum) lactitarse Saussure (Hymenoptera, Crabronidae) in trap-nests in Southern Brazil

OpenAIRE

Buschini,M. L. T.; Niesing,F.; Wolff,L. L.

2006-01-01

This study was carried in the Parque Municipal das Araucárias in the municipality of Guarapuava, state of Paraná, Southern Brazil. Three hundred and sixty five nests of T. lactitarse were obtained using trap-nests of 0.7, 1.0, and 1.3 cm in diameter. All of them had similar architecture, regardless of the diameter of the trap-nest. Completed nests consisted of a linear series of brood cells whose average number per nest was of 3.3, 4.0 and 3.6 for the nests with 0.7 cm, 1.0 cm and 1.3 cm in d...

Louisiana ESI: NESTS (Nest Points)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for seabird and wading bird nesting colonies in coastal Louisiana. Vector points in this data set represent...

Aplicación de técnicas de pruebas automáticas basadas en propiedades a los diferentes niveles de prueba del software

OpenAIRE

Francisco Fernández, Miguel Ángel

2016-01-01

[Resumen]Las pruebas son una de las actividades clave en el desarrollo de software, puesto que ayudan a detectar defectos que, de otro modo, pasarían desapercibidos hasta que el software sea desplegado. Sin embargo, al contrario que en otras etapas del ciclo de vida del software, como son el análisis, el diseño o la implementación, para las que existen metodologías y técnicas bien definidas y ampliamente aceptadas en la comunidad informática, junto con herramientas que permiten llevar a cabo ...

Rendimiento de la prueba Xpert MTB/RIF en muestras respiratorias en el escenario real de trabajo en un país en desarrollo

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Santiago Atehortúa

2015-03-01

Full Text Available Introducción. La prueba Xpert MTB/RIF detecta el ADN del complejo Mycobacterium tuberculosis y la sensibilidad a rifampicina. La prueba ha sido evaluada en condiciones “ideales” que incluyen la centrifugación de esputo y el lavado broncoalveolar, la tinción de Ziehl Neelsen (ZN y de auramina-rodamina y los métodos de cultivo sólido y de cultivo líquido automatizado. Los resultados de tales evaluaciones no pueden extrapolarse a países de bajos ingresos que no utilizan habitualmente todos estos procesos. Objetivo. Evaluar el rendimiento de la prueba Xpert MTB/RIF en muestras respiratorias bajo condiciones “reales” de trabajo y su correlación con las pruebas fenotípicas de sensibilidad. Materiales y métodos. Se llevó a cabo un estudio transversal para evaluar el rendimiento de la prueba Xpert MTB/RIF en pacientes ≥12 años con sospecha de tuberculosis pulmonar. En el procesamiento rutinario de muestras en el Hospital del estudio no se usa la centrifugación del esputo, la tinción con auramina-rodamina ni el cultivo líquido automatizado. Resultados.Se incluyeron 152 pacientes, de los cuales 108 eran elegibles y 103 se incluyeron en el análisis. El 34 % de las muestras fueron positivas; la sensibilidad de la prueba fue de 91 %, la especificidad de 92 %, el valor diagnóstico positivo de 83 % y el valor diagnóstico negativo global de 96 %. En las muestras negativas con Ziehl Neelsen, la sensibilidad fue de 87 %, la especificidad de 91 % y los valores diagnósticos positivo y negativo alcanzaron 68 y 97 %, respectivamente. Los resultados de sensibilidad o resistencia a la rifampicina concordaron con los de la prueba fenotípica de sensibilidad (valor de kappa=1, p<0,0001. Conclusiones. El rendimiento global de la prueba fue similar al obtenido bajo condiciones “ideales”. En las muestras negativas con Ziehl Neelsen se obtuvo un mejor rendimiento en las condiciones “reales” de trabajo de un país de bajos ingresos

Prueba de Elisa indirecta para la detección de anticuerpos IgM para el diagnóstico de Leptospirosis humana

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Manuel Céspedes Z

2002-01-01

Full Text Available Para el diagnóstico temprano de enfermedades con cuadro clínico inespecífico como la leptospirosis, es necesario la confirmación laboratorial mediante pruebas específicas, con la finalidad de que el diagnóstico sea más acertado y rápido. Objetivo: se realizó un estudio comparativo entre la prueba de microaglutinacion (MAT y la prueba de ELISA indirecta estandarizada con un "pool" de antígenos de Leptospira interrogans, para la detección de anticuerpos IgM, en muestras de suero de fase aguda de leptospirosis humana. Materiales y métodos: 40 muestras de pacientes con sospecha clínica y con títulos de 1:100-1:12800 por la prueba de MAT, 80 muestras negativas de pacientes aparentemente sanos con enfermedades como Brucelosis, Sífilis, Tifus murino, Hepatitis B, Fiebre Amarilla, Dengue y Enfermedad de Carrión fueron evaluados por ELISA IgM. Resultados: se obtuvo una sensibilidad de 97,5% y especificidad de 98,75%, no observándose reacción cruzada con otras enfermedades. Conclusión: ELISA IgM validado en el laboratorio es suficiente sensible, específico y de fácil aplicación para el uso como prueba de tamizaje en una infección por Leptospiras con la subsecuente confirmación por MAT.

Raptor nest management on power lines

Energy Technology Data Exchange (ETDEWEB)

Harness, R.E. [EDM International Inc., Fort Collins, CO (United States)

2005-07-01

Many utilities in South Africa are now implementing labor-intensive methods to combat raptor nesting on power transmission lines. Methods have typically included direct nest removal and trimming of nest materials. However, the process is often unsuccessful, and utilities are now learning to accommodate the raptor nests. This paper argued that managing nests on utility structures has solved many operational problems and has resulted in positive publicity for many line operators. Nest management options included the use of stick deflectors to prevent nest material from accumulating during initial nest construction, as well as encouraging raptors to shift their efforts to a more suitable location. Raptors will often accept alternative nesting platforms, and taller, surrogate nesting poles can be placed next to distribution line structures. Elevated platforms can also be placed on problematic distribution structures, but may result in birds coming into contact with unprotected equipment. It was concluded that a successful nest management program includes plans to make nearby lines safe for raptors and to prevent their electrocution. Providing nests with bird-friendly utility configurations can result in electric facilities enhancing wild raptor populations without impacting power reliability. 14 refs., 9 figs.

Prueba de dosificación de la sembradora V-20 con semilla de amaranto (amaranthus hypochondriacus l.)

OpenAIRE

Pedro Mayans Céspedes; José R. Soca Cabrera; Gilberto López Canteñs; Eugenio Romantchik Kriuchkova

2009-01-01

En el presente trabajo se muestran los resultados de la prueba de dosificación realizada a la sembradora V-20 con semilla de amaranto. Para la prueba se contó con un banco construido en las instalaciones del Centro Nacional de Estandarización de Maquinaria Agrícola (CENEMA), utilizándose la Norma Mexicana: "Método de evaluación de sembradoras y/o fertilizadoras de tracción mecánica con dosificador de disco" y la Norma Cubana 34-50 "Sembradora de granos, metodología para la realización de las ...

La dosificación del ácido hipúrico en la Prueba de Quick

Directory of Open Access Journals (Sweden)

Cecilia Hernández de Paredes

1948-01-01

Full Text Available Trabajo realizado en el Instituto de Investigaciones Médico-quirúrgicas de la Facultad de Medicina de la Universidad Nacional. El empleo de la prueba de síntesis del ácido hipúrico en la apreciación del estado funcional del hígado es uno de los procedimientos que más difusión han tenido en los últimos años. Su popularidad no solamente es debida a la relativa sencillez e inocuidad del procedimiento sino también a su notable valor en el diagnóstico de las enfermedades del hígado. Numerosos investigadores la emplean actualmente con esta finalidad y en la literatura corriente figura como -una de las pruebas de rutina a pesar de que no siempre sus resultados han dejado satisfechos a todos.

Nest-site selection and nest success of an Arctic-breeding passerine, Smith's Longspur, in a changing climate

Science.gov (United States)

McFarland, Heather R.; Kendall, Steve J.; Powell, Abby

2017-01-01

Despite changes in shrub cover and weather patterns associated with climate change in the Arctic, little is known about the breeding requirements of most passerines tied to northern regions. We investigated the nesting biology and nest habitat characteristics of Smith's Longspurs (Calcarius pictus) in 2 study areas in the Brooks Range of Alaska, USA. First, we examined variation in nesting phenology in relation to local temperatures. We then characterized nesting habitat and analyzed nest-site selection for a subset of nests (n = 86) in comparison with paired random points. Finally, we estimated the daily survival rate of 257 nests found in 2007–2013 with respect to both habitat characteristics and weather variables. Nest initiation was delayed in years with snow events, heavy rain, and freezing temperatures early in the breeding season. Nests were typically found in open, low-shrub tundra, and never among tall shrubs (mean shrub height at nests = 26.8 ± 6.7 cm). We observed weak nest-site selection patterns. Considering the similarity between nest sites and paired random points, coupled with the unique social mating system of Smith's Longspurs, we suggest that habitat selection may occur at the neighborhood scale and not at the nest-site scale. The best approximating model explaining nest survival suggested a positive relationship with the numbers of days above 21°C that an individual nest experienced; there was little support for models containing habitat variables. The daily nest survival rate was high (0.972–0.982) compared with that of most passerines in forested or grassland habitats, but similar to that of passerines nesting on tundra. Considering their high nesting success and ability to delay nest initiation during inclement weather, Smith's Longspurs may be resilient to predicted changes in weather regimes on the breeding grounds. Thus, the greatest threat to breeding Smith's Longspurs associated with climate change may be the loss of low

Nesting Activity of Loggerhead Turtles (Caretta caretta at Göksu Delta, Turkey during 2004 and 2008 nesting seasons

Directory of Open Access Journals (Sweden)

Salih H. Durmus

2011-07-01

Full Text Available Göksu Delta is one of the most important nesting beaches in Turkey for the endangered loggerhead turtle (Caretta caretta. This paper provides information on the nesting activities of loggerhead turtles, the spatial and temporal distribution of nesting, nesting success, nesting density, hatching success, incubation duration and clutch size over two nesting seasons. A total of 902 emergences occurred over two seasons, of which 239 (26.5% nests were deposited (137 nests in 2004 and 102 nests in 2008 and the overall mean nesting density was 3.4 nests/km. The peak of nesting emergences takes place mainly in June. Of the overall nests, 226 (94.6% were excavated and 16044 eggs were counted. Of these eggs, 3680 (22.9% hatchlings emerged and 2695 (73.2% of hatchlings of them were able to reach the sea. The mean number of eggs per clutch was 71 (range: 15 – 143. The shortest and longest incubation duration in these 2 seasons ranged from 46 to 62 days with a mean of 53 days. The main problems are negatively affecting loggerhead turtle population at Göksu Delta are dense jackal predation both adult and eggs and inundation in nests. The average nesting effort here (mean: 119.5 nests/season confirms that Göksu Delta is one of the most important nesting sites for loggerhead turtles in Turkey.

Buteo Nesting Ecology: Evaluating Nesting of Swainson’s Hawks in the Northern Great Plains

Science.gov (United States)

Inselman, Will M.; Datta, Shubham; Jenks, Jonathan A.; Jensen, Kent C.; Grovenburg, Troy W.

2015-01-01

Swainson’s hawks (Buteo swainsoni) are long-distance migratory raptors that nest primarily in isolated trees located in areas of high grassland density. In recent years, anthropogenic conversion of grassland habitat has raised concerns about the status of the breeding population in the northern Great Plains. In 2013, we initiated a study to investigate the influence of extrinsic factors influencing Swainson’s hawk nesting ecology in north-central South Dakota and south-central North Dakota. Using ground and aerial surveys, we located and monitored nesting Swainson’s hawk pairs: 73 in 2013 and 120 in 2014. We documented 98 successful breeding attempts that fledged 163 chicks; 1.52 and 1.72 fledglings per successful nest in 2013 and 2014, respectively. We used Program MARK to evaluate the influence of land cover on nest survival. The top model, S Dist2Farm+%Hay, indicated that nest survival (fledging at least one chick) decreased as nests were located farther from farm sites and as the percent of hay cover increased within 1200-m of the nest site (34.4%; 95% CI = 27.6%–42.3%). We used logistic regression analysis to evaluate the influence of landscape variables on nest-site selection; Swainson’s hawks selected for nest sites located closer to roads. We suggest that tree belts associated with farm sites, whether occupied or not, provide critical breeding sites for Swainson’s hawks. Additionally, poor breeding success may be related to the late migratory behavior of this species which requires them to occupy marginal habitat due to other raptors occupying the most suitable habitat prior to Swainson’s hawks arriving to the breeding grounds. PMID:26327440

Unusual raptor nests around the world

Science.gov (United States)

Ellis, D.H.; Craig, T.; Craig, E.; Postupalsky, S.; LaRue, C.T.; Nelson, R.W.; Anderson, D.W.; Henny, C.J.; Watson, J.; Millsap, B.A.; Dawson, J.W.; Cole, K.L.; Martin, E.M.; Margalida, A.; Kung, P.

2009-01-01

From surveys in many countries, we report raptors using unusual nesting materials (e.g., paper money, rags, metal, antlers, and large bones) and unusual nesting situations. For example, we documented nests of Steppe Eagles Aquila nipalensis and Upland Buzzards Buteo hemilasius on the ground beside well-traveled roads, Saker Falcon Falco cherrug eyries in attics and a cistern, and Osprey Pandion haliaetus nests on the masts of boats and on a suspended automobile. Other records include a Golden Eagle A. chrysaetos nest 7.0 m in height, believed to be the tallest nest ever described, and, for the same species, we report nesting in rudimentary nests. Some nest sites are within a few meters of known predators or competitors. These unusual observations may be important in revealing the plasticity of a species' behavioral repertoire. ?? 2009 The Raptor Research Foundation, Inc.

Validez de una prueba rápida dual para detección de VIH/sífilis en tres delegaciones del Instituto Mexicano del Seguro Social (IMSS

Directory of Open Access Journals (Sweden)

M.O. Coreño Juárez

2015-01-01

Full Text Available A pesar de que existen muchas pruebas para realizar tamiz para la detección de infección por el virus de la inmunodeficiencia humana (VIH o para sífilis, hasta el momento en nuestro país no se ha evaluado una prueba dual que permita disminuir las oportunidades perdidas para la detección de ambas enfermedades. El objetivo del estudio fue conocer la confiabilidad de una prueba rápida dual de tamiz para la detección de VIH y sífilis en población derechohabiente de tres delegaciones del Instituto Mexicano del Seguro Social (IMSS. Se realizó un estudio epidemiológico que permitió conocer el valor diagnóstico de la prueba, a través de la determinación de sus valores de sensibilidad y especificidad, con la finalidad de evaluar su uso como prueba de tamizaje para la infección por el VIH/sida y para sífilis, con una tasa de detección similar a la de las pruebas convencionales utilizadas por separado.

Sexually selected nest-building--Pomatoschistus minutus males build smaller nest-openings in the presence of sneaker males.

Science.gov (United States)

Svensson, O; Kvarnemo, C

2003-09-01

Both natural selection and sexual selection may act on nest-building. We tested experimentally how different regimes of egg-predation and male-male competition influence nest-building before mating, using the marine fish sand goby, Pomatoschistus minutus. Males with sneaker males present built the smallest nest-openings, smaller than males held alone or with Pomatoschistus microps males (which may predate eggs and compete over nest-sites but not compete over fertilizations). Males with visual access to other nest-building males tended also to build smaller openings than males held alone or with P. microps. Males with egg-predators present built nests with openings not differing significantly from any other treatment. Our results indicate that the small nest-openings found in the sneaker male treatment are sexually selected through protection against sneaking or by female choice. Across treatments, time span before a male started to build his nest also explained variation in nest-opening width; males starting late built larger nest-openings.

Evaluación de la validez y confiabilidad de una prueba diagnóstica

Directory of Open Access Journals (Sweden)

José H. Donis Hernández

2012-07-01

Full Text Available En esta revisión se discuten, de manera resumida, los conceptos fundamentales de lo que significa la validez de una prueba a través de sus índices, como son la sensibilidad y especificidad, consideradas como propiedades intrínsecas de una prueba diagnóstica. Así mismo, se exponen los conceptos fundamentales de los valores predictivos positivos y negativos en la práctica clínica y su asociación con la prevalencia de la enfermedad estudiada. Seguidamente se analizan las razones de verosimilitud o de probabilidad, las cuales, como su nombre lo indica, son razones que evidencian con qué frecuencia un individuo padece una enfermedad, cuando son positivas, en relación con otro individuo que no la padece, la cual también es positiva Adicionalmente, se evaluan las curvas ROC como una metodología para categorizar en forma dicotómica es decir, positivos o negativos, aquellas pruebas con valores en escala continua. Finalmente, se discute la confiabilidad de una prueba, parámetro de gran valor en la veracidad de cualquier prueba que se realice en forma cotidiana en la práctica clínica, ya que asegura la repetitividad de la misma en el sitio de su ejecución. Palabras clave: Sensibilidad, Especificidad, Valores predictivos, Razón de verosimilitud, Curvas ROC y Confiabilidad. Assessment of the validity and reliability of a diagnostic test Abstract This review is intended to explain briefly, the significance of the validity of a diagnostic test by using specific indicators such as: the sensitivity, and the specificity, which are considered as intrinsic properties of the test. Additionally, the fundamental concepts of positive and negative predictive values of a diagnostic test in the clinical practice, are described and highlighted, and their connection to the prevalence of a particular disease. The likelihood ratio, meaning how many times a healthy person suffers from a disease, in other words, the percentage of ill people diagnosed with a

Development with age of nest box use and gregarious nesting in laying hens

DEFF Research Database (Denmark)

Riber, Anja Brinch

2010-01-01

in position (left + corner, middle, and right). Nesting behaviour was video recorded for 5 days in each of five distinct periods: age 20, 26, 32, 38, and 44 weeks. The total number of visits and the number of gregarious visits were higher in the left nest box than in the other two nest boxes at all ages...

Predation on simulated duck nests in relation to nest density and landscape structure

Czech Academy of Sciences Publication Activity Database

Padyšáková, E.; Šálek, Martin; Poledník, L.; Sedláček, František; Albrecht, Tomáš

2010-01-01

Roč. 37, č. 7 (2010), s. 597-603 ISSN 1035-3712 R&D Projects: GA MŠk LC06073 Institutional research plan: CEZ:AV0Z60870520; CEZ:AV0Z60930519 Keywords : density-dependent predation * littoral patch * landscape type * nest predators * nest success * simulated nests Subject RIV: EG - Zoology Impact factor: 1.205, year: 2010

Frecuencia de discapacidad en estudiantes que presentan la prueba estandarizada de acceso a la educación superior (Saber 11 en Colombia y caracterización de su rendimiento

Directory of Open Access Journals (Sweden)

Andrea Padilla Muñoz

2012-10-01

Este estudio sugiere que son pocas las PCD que se presentan a la prueba Saber 11. No existe forma de evidenciar discapacidad cognitiva en la prueba.529.651 estudiantes presentaron la prueba por primera vez, de los cuales el 0,2% (842 afirmaron durante la inscripción tener algún tipo de discapacidad. Del total de PCD, el 35,0% presentó una discapacidad motora, el 34,9% presentó una discapacidad auditiva y requirieron intérprete en la prueba, 19,1% presentó una discapacidad visual y un 11,5% presentó discapacidad auditiva, pero no requirieron intérprete. La mayoría de sus puntajes están en categorización media, y, en promedio, las personas con discapacidad visual tuvieron resultados mejores en las áreas básicas al compararlos con otras discapacidades.Análisis secundario de tipo descriptivo de los resultados del examen nacional de acceso a la educación superior (prueba Saber 11, presentado por PCD en el año 2009. La certificación de discapacidades realizada previa al examen durante la inscripción a la prueba. Se describen las características de dicha población, junto con los puntajes en la prueba.Describir las características y el rendimiento en la prueba Saber 11 de las personas con discapacidad (PCD en 2009.El examen nacional de acceso a la educación superior en Colombia (prueba Saber 11, es obligatorio para obtener el título de bachiller y ha realizado adaptaciones que permiten evaluar a personas con discapacidad física, auditiva y visual.

Discovery of a new Kittlitz's murrelet nest: Clues to habitat selection and nest-site fidelity

Science.gov (United States)

Piatt, John F.; Naslund, Nancy L.; van Pelt, Thomas I.

1999-01-01

On 13 June 1993, a new Kittlitz's murrelet (Brachyramphus brevirostris) nest was discovered near Red Mountain on the Kenai Peninsula, Alaska. The nest was on a 22° slope at about 900 m elevation with a northeast aspect, and contained a 60.2 × 40.6 mm egg that weighed 49.0 g. Downy feathers and weathered fecal material found at the nest indicated re-use from a previous year, suggesting possible nest site fidelity. The nest was located in an area scoured by winds and free of snow during early spring, suggesting that this may be an important mesoscale factor influencing selection of nesting habitat. Proximity to suitable foraging habitat, particularly sheltered bays and glacial river outflows, may affect breeding habitat choice over larger spatial scales.

APLICACIONES ADICIONALES DE LOS RESULTADOS DE PRUEBAS DE CARGA ESTÁTICAS EN EL DISEÑO GEOTÉCNICO DE CIMENTACIONES

Directory of Open Access Journals (Sweden)

YAMILE VALENCIA

2012-01-01

Full Text Available Generalmente las pruebas de carga no hacen parte de la rutina de obras de cimentaciones ejecutadas en Suramérica, y cuando son ejecutadas, el análisis queda restringido a la determinación o estimación de la capacidad de carga de la fundación. No obstante, pueden hacerse otros análisis de modo que el calculista cuente con mayores elementos de juicio en lo referente al comportamiento de la cimentación. El presente articulo muestra un conjunto de análisis complementarios, que pueden ser hechos a partir de los resultados obtenidos para una prueba de carga teniendo en cuenta el comportamiento característico de cada suelo y los mecanismos de interacción entre la estructura de cimentación y el suelo de soporte, a partir del análisis de los resultados de pruebas de carga realizadas sobre pilotes ejecutados con hélice continua.

Análisis de costes y ahorros potenciales relacionados con la utilización de pruebas preoperatorias en los hospitales de Canarias

Directory of Open Access Journals (Sweden)

López-Bastida J.

2003-01-01

Full Text Available Objetivos: Estimar el ahorro potencial que podría tener lugar en el Servicio Canario de Salud (SCS, a partir de una utilización apropiada científica de las pruebas preoperatorias, haciendo uso de la información obtenida de los 5 hospitales universitarios de la red pública. Métodos: Un total de 55 anestesiólogos (60% del SCS cumplimentaron un cuestionario. En éste se prestó especial atención a las pruebas preoperatorias más frecuentemente utilizadas, como la radiografía de tórax, el electrocardiograma, las pruebas de laboratorio y la espirometría. Los costes unitarios medios para las diferentes pruebas preoperatorias se obtuvieron de 2 hospitales participantes en el estudio. Para calcular los ahorros potenciales derivados del uso apropiado de las pruebas preoperatorias se han considerado varios escenarios caracterizados por diferentes hipótesis o grados de cumplimiento de un protocolo basado en el conocimiento científico, considerado como parámetro de referencia. Resultados: En el caso ideal de que se cumpliera el protocolo científico recomendado en el 100% de los 16.179 pacientes considerados ASA I y II, la repercusión económica sería notable, pues supondría una liberación de recursos sensible que podría ser utilizada para otros programas de salud. Estas cifras podrían alcanzar aproximadamente los 1,02 millones de euros, sin considerar el coste de la estancia preoperatoria. Esta cifra podría incrementarse hasta, aproximadamente, los 2,13 millones de euros si incluimos un día de estancia preoperatoria, y hasta los 3,24 millones de euros incluyendo 2 días de estancia preoperatoria. Conclusiones: La revisión reciente de la literatura científica y los resultados proporcionados por el cuestionario aplicado en el SCS indican que las pruebas preoperatorias alcanzan los mayores beneficios para los pacientes y para la sociedad si se guían por el conocimiento científico. Es posible, además, liberar recursos a partir de una

Nest-site selection by cavity-nesting birds in relation to postfire salvage logging

Science.gov (United States)

Victoria A. Saab; Robin E. Russell; Jonathan G. Dudley

2009-01-01

Large wildfire events in coniferous forests of the western United States are often followed by postfire timber harvest. The long-term impacts of postfire timber harvest on fire-associated cavity-nesting bird species are not well documented. We studied nest-site selection by cavity-nesting birds over a 10-year period (1994-2003), representing 1-11 years after fire, on...

Artificial covering on trap nests improves the colonization of trap-nesting wasps

OpenAIRE

Taki, Hisatomo; Kevan, Peter G.; Viana, Blandina Felipe; Silva, Fabiana O.; Buck, Matthias

2008-01-01

Acesso restrito: Texto completo. p. 225-229 To evaluate the role that a trap-nest cover might have on sampling methodologies, the abundance of each species of trap-nesting Hymenoptera and the parasitism rate in a Canadian forest were compared between artificially covered and uncovered traps. Of trap tubes exposed at eight forest sites in six trap-nest boxes, 531 trap tubes were occupied and 1216 individuals of 12 wasp species of four predatory families, Vespidae (Eumeninae), Crabronidae...

Nest Predation Deviates from Nest Predator Abundance in an Ecologically Trapped Bird

OpenAIRE

Hollander, Franck A.; Van Dyck, Hans; San Martin, Gilles; Titeux, Nicolas

2015-01-01

In human-modified environments, ecological traps may result from a preference for low-quality habitat where survival or reproductive success is lower than in high-quality habitat. It has often been shown that low reproductive success for birds in preferred habitat types was due to higher nest predator abundance. However, between-habitat differences in nest predation may only weakly correlate with differences in nest predator abundance. An ecological trap is at work in a farmland bird (Lanius ...

Interaction in Balanced Cross Nested Designs

Science.gov (United States)

Ramos, Paulo; Mexia, João T.; Carvalho, Francisco; Covas, Ricardo

2011-09-01

Commutative Jordan Algebras, CJA, are used in the study of mixed models obtained, through crossing and nesting, from simpler ones. In the study of cross nested models the interaction between nested factors have been systematically discarded. However this can constitutes an artificial simplification of the models. We point out that, when two crossed factors interact, such interaction is symmetric, both factors playing in it equivalent roles, while when two nested factors interact, the interaction is determined by the nesting factor. These interactions will be called interactions with nesting. In this work we present a coherent formulation of the algebraic structure of models enabling the choice of families of interactions between cross and nested factors using binary operations on CJA.

Parental investment decisions in response to ambient nest-predation risk versus actual predation on the prior nest

Science.gov (United States)

Chalfoun, A.D.; Martin, T.E.

2010-01-01

Theory predicts that parents should invest less in dependent offspring with lower reproductive value, such as those with a high risk of predation. Moreover, high predation risk can favor reduced parental activity when such activity attracts nest predators. Yet, the ability of parents to assess ambient nest-predation risk and respond adaptively remains unclear, especially where nest-predator assemblages are diverse and potentially difficult to assess. We tested whether variation in parental investment by a multi-brooded songbird (Brewer's Sparrow, Spizella breweri) in an environment (sagebrush steppe) with diverse predators was predicted by ambient nest-predation risk or direct experience with nest predation. Variation among eight sites in ambient nest-predation risk, assayed by daily probabilities of nest predation, was largely uncorrelated across four years. In this system risk may therefore be unpredictable, and aspects of parental investment (clutch size, egg mass, incubation rhythms, nestling-feeding rates) were not related to ambient risk. Moreover, investment at first nests that were successful did not differ from that at nests that were depredated, suggesting parents could not assess and respond to territorylevel nest-predation risk. However, parents whose nests were depredated reduced clutch sizes and activity at nests attempted later in the season by increasing the length of incubation shifts (on-bouts) and recesses (off-bouts) and decreasing trips to feed nestlings. In this unpredictable environment parent birds may therefore lack sufficient cues of ambient risk on which to base their investment decisions and instead rely on direct experience with nest predation to inform at least some of their decisions. ?? 2010 The Cooper Ornithological Society.

Landscape forest cover and edge effects on songbird nest predation vary by nest predator

Science.gov (United States)

W. Andrew Cox; Frank R. III Thompson; John. Faaborg

2012-01-01

Rates of nest predation for birds vary between and within species across multiple spatial scales, but we have a poor understanding of which predators drive such patterns. We video-monitored nests and identified predators at 120 nests of the Acadian Flycatcher (Empidonax virescens) and the Indigo Bunting (Passerina cyanea) at eight...

Nest Material Shapes Eggs Bacterial Environment.

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Cristina Ruiz-Castellano

Full Text Available Selective pressures imposed by pathogenic microorganisms to embryos have selected in hosts for a battery of antimicrobial lines of defenses that includes physical and chemical barriers. Due to the antimicrobial properties of volatile compounds of green plants and of chemicals of feather degrading bacteria, the use of aromatic plants and feathers for nest building has been suggested as one of these barriers. However, experimental evidence suggesting such effects is scarce in the literature. During two consecutive years, we explored experimentally the effects of these nest materials on loads of different groups of bacteria (mesophilic bacteria, Enterobacteriaceae, Staphylococcus and Enterococcus of eggshells in nests of spotless starlings (Sturnus unicolor at the beginning and at the end of the incubation period. This was also explored in artificial nests without incubation activity. We also experimentally increased bacterial density of eggs in natural and artificial nests and explored the effects of nest lining treatments on eggshell bacterial load. Support for the hypothetical antimicrobial function of nest materials was mainly detected for the year and location with larger average values of eggshell bacterial density. The beneficial effects of feathers and plants were more easily detected in artificial nests with no incubation activity, suggesting an active role of incubation against bacterial colonization of eggshells. Pigmented and unpigmented feathers reduced eggshell bacterial load in starling nests and artificial nest boxes. Results from artificial nests allowed us to discuss and discard alternative scenarios explaining the detected association, particularly those related to the possible sexual role of feathers and aromatic plants in starling nests. All these results considered together confirm the antimicrobial functionality mainly of feathers but also of plants used as nest materials, and highlight the importance of temporally and

Nest Material Shapes Eggs Bacterial Environment.

Science.gov (United States)

Ruiz-Castellano, Cristina; Tomás, Gustavo; Ruiz-Rodríguez, Magdalena; Martín-Gálvez, David; Soler, Juan José

2016-01-01

Selective pressures imposed by pathogenic microorganisms to embryos have selected in hosts for a battery of antimicrobial lines of defenses that includes physical and chemical barriers. Due to the antimicrobial properties of volatile compounds of green plants and of chemicals of feather degrading bacteria, the use of aromatic plants and feathers for nest building has been suggested as one of these barriers. However, experimental evidence suggesting such effects is scarce in the literature. During two consecutive years, we explored experimentally the effects of these nest materials on loads of different groups of bacteria (mesophilic bacteria, Enterobacteriaceae, Staphylococcus and Enterococcus) of eggshells in nests of spotless starlings (Sturnus unicolor) at the beginning and at the end of the incubation period. This was also explored in artificial nests without incubation activity. We also experimentally increased bacterial density of eggs in natural and artificial nests and explored the effects of nest lining treatments on eggshell bacterial load. Support for the hypothetical antimicrobial function of nest materials was mainly detected for the year and location with larger average values of eggshell bacterial density. The beneficial effects of feathers and plants were more easily detected in artificial nests with no incubation activity, suggesting an active role of incubation against bacterial colonization of eggshells. Pigmented and unpigmented feathers reduced eggshell bacterial load in starling nests and artificial nest boxes. Results from artificial nests allowed us to discuss and discard alternative scenarios explaining the detected association, particularly those related to the possible sexual role of feathers and aromatic plants in starling nests. All these results considered together confirm the antimicrobial functionality mainly of feathers but also of plants used as nest materials, and highlight the importance of temporally and geographically

Design of nest access grids and perches in front of the nests: Influence on the behavior of laying hens.

Science.gov (United States)

Stämpfli, K; Buchwalder, T; Fröhlich, E K F; Roth, B A

2013-04-01

In aviary systems for laying hens, it is important to provide suitable nest access platforms in front of the nests, allowing hens to reach and explore each of the nests easily. This access platform is needed to achieve good nest acceptance by the hens and thereby prevent mislaid eggs. In the present experiment, the behavior of hens using 2 different nest access platforms, a plastic grid and 2 wooden perches, was examined. Furthermore, the nests were placed on both sides of the aviary rack (corridor side and outdoor side), either integrated into the aviary rack itself (integrated nest; IN) or placed on the walls of the pens (wall nest; WN), resulting in a 2 × 2 factorial design Four thousand five hundred white laying hens were housed in 20 test pens. The eggs in the nests and mislaid eggs were collected daily, and the behavior of hens on the nest accesses was filmed during wk 25 and 26, using focal observation and scan sampling methods. More balancing, body contact, and agonistic interactions were expected for nests with perches, whereas more walking and nest inspections were expected for nests with grids. There were more mislaid eggs and balancing found in pens equipped with nests with wooden perches. More agonistic interactions and balancing, less standing, and a longer duration of nest inspection were found with the WN compared with the IN. Interactions between platform design and position of the nests were found for duration of nest visits, body contact, and walking, with the highest amount for WN equipped with plastic grids. Nests on the corridor side were favored by the hens. Nest-related behaviors, such as nest inspection, standing, and walking, decreased over time as did the number of hens on the nest accesses, whereas sitting increased. These results indicate that the hens had more difficulties in gripping the perches as designed. The lower number of hens on the nest access platforms in front of IN may be due to a better distribution around nests and tier

Small-scale area effect on species richness and nesting occupancy of cavity-nesting bees and wasps

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Rafael D. Loyola

2011-03-01

Full Text Available Small-scale area effect on species richness and nesting occupancy of cavity-nesting bees and wasps. The research was conducted in an urban forest remnant in southeast Brazil. We tested the predictions of the following hypotheses: (1 larger areas present higher species richness of bees and wasps, (2 solitary bees and wasps occupy more nests in larger areas, (3 rare species occupy more nests in smaller areas. We sampled Aculeate bees and wasps using trap nests from February to November 2004. We placed trap nests in sampling units (SU with different size (25, 100 and 400 m² located in 6 ha of secondary mesophytic forest. One hundred and thirty-seven trap nests were occupied by seven species of bees and four species of wasps. We found an increase in wasp, but not bee species richness following increase in SU size. Hymenoptera richness (i.e. bees plus wasps was also greater in larger SU. Both the number and density of occupied nests increased with SU size. The wasp Trypoxylon lactitarse responded significantly to area size, larger SU having more occupied nests. The same pattern was exhibited by the wasp Auplopus militaris, the Megachile bee species, and the bee Anthodioctes megachiloides. Only Trypoxylon sp. was not affected by SU size. Our results show that cavity-nesting bee and wasps respond differently to the area effects. Such findings must be complemented by information on the frequency and dynamics of area colonization and nest occupancy by species of solitary Hymenoptera.

LA PRUEBA DOCUMENTADA EN EL NUEVO SISTEMA DE JUSTICIA PENAL MEXICANO Documented proof in the new Mexican criminal justice system

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Benavente Chorres Hesbert

2010-01-01

Full Text Available El presente estudio analiza los supuestos de prueba documentada regulados en aquellos códigos de las entidades federativas mexicanas que han adecuado el proceso penal al sistema acusatorio con tendencia adversarial. En ese sentido, se entiende por prueba documentada aquellas diligencias, principalmente declaraciones, realizadas durante la etapa de investigación que la ley otorga valor probatorio al no poder asistir el órgano de prueba a la audiencia del juicio oral por razones ajenas a su voluntad.This study analyzes the cases of the documented proof in those codes regulated the Mexican states that have appropriate criminal proceedings prone to adversarial system. In that sense, it is understood by those measures documented evidence, primarily statements made during the investigation stage that the law gives the probative value could not attend the court hearing to test the trial for reasons beyond their control.

Bee species-specific nesting material attracts a generalist parasitoid: implications for co-occurring bees in nest box enhancements.

Science.gov (United States)

Macivor, J Scott; Salehi, Baharak

2014-08-01

Artificial nests (e.g., nest boxes) for bees are increasingly being used to contribute to nesting habitat enhancement for bees that use preexisting cavities to provision brood. They usually incorporate additional nesting materials that vary by species. Cavity-nesting bees are susceptible to brood parasitoids that recognize their host(s) using visual and chemical cues. Understanding the range of cues that attract parasitoids to bee nests, including human-made analogues, is important if we wish to control parasitism and increase the potential value of artificial nests as habitat-enhancement strategies. In this study, we investigated the cues associated with the orientation of the generalist brood parasitoid Monodontomerus obscurus Westwood (Hymenoptera: Torymidae) to the nests of a common cavity-nesting resin bee Megachile campanulae (Robertson) (Megachilidae). The parasitoids were reared from previously infested M. campanulae brood cells and placed into choice trials where they were presented with pairs of different nest material cues. Among different materials tested, we found that Mo. obscurus was most attracted to fresh resin collected directly from Pinus strobus trees followed by previously used resin collected from the bee nest. The parasitoid also attacked other bee species in the same nest boxes, including those that do not use resin for nesting. Our findings suggest that M. campanulae could act as a magnet, drawing parasites away from other bee hosts co-occurring in nest boxes, or, as an attractant of Mo. obscurus to nest boxes, increasing attacks on co-occurring host bee species, potentially undermining bee diversity enhancement initiatives.

Nested Potential Games

OpenAIRE

Hiroshi Uno

2007-01-01

This paper proposes a new class of potential games, the nested potential games, which generalize the potential games defined in Monderer and Shapley (1996), as well as the pseudo-potential games defined in Dubey et al. (2006). We show that each maximizer of a nested potential is a Nash equilibrium.

Nesting ecology and nest survival of lesser prairie-chickens on the Southern High Plains of Texas

Science.gov (United States)

Grisham, Blake A.; Borsdorf, Philip K.; Boal, Clint W.; Boydston, Kathy K.

2014-01-01

The decline in population and range of lesser prairie-chickens (Tympanuchus pallidicinctus) throughout the central and southern Great Plains has raised concerns considering their candidate status under the United States Endangered Species Act. Baseline ecological data for lesser prairie-chickens are limited, especially for the shinnery oak-grassland communities of Texas. This information is imperative because lesser prairie-chickens in shinnery oak grasslands occur at the extreme southwestern edge of their distribution. This geographic region is characterized by hot, arid climates, less fragmentation, and less anthropogenic development than within the remaining core distribution of the species. Thus, large expanses of open rangeland with less anthropogenic development and a climate that is classified as extreme for ground nesting birds may subsequently influence nest ecology, nest survival, and nest site selection differently compared to the rest of the distribution of the species. We investigated the nesting ecology of 50 radio-tagged lesser prairie-chicken hens from 2008 to 2011 in the shinnery oak-grassland communities in west Texas and found a substantial amount of inter-annual variation in incubation start date and percent of females incubating nests. Prairie-chickens were less likely to nest near unimproved roads and utility poles and in areas with more bare ground and litter. In contrast, hens selected areas dominated by grasses and shrubs and close to stock tanks to nest. Candidate models including visual obstruction best explained daily nest survival; a 5% increase in visual obstruction improved nest survival probability by 10%. The model-averaged probability of a nest surviving the incubation period was 0.43 (SE = 0.006; 95% CI: 0.23, 0.56). Our findings indicate that lesser prairie-chicken reproduction during our study period was dynamic and was correlated with seasonal weather patterns that ultimately promoted greater grass growth earlier in the

Rendimiento de los titulados en psicología en las pruebas de acceso de PIR

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Eva Expósito-Casas

Full Text Available Resumen Entre las titulaciones más demandadas por parte de los futuros estudiantes universitarios, figura el Grado en Psicología. Este interés ha traído consigo un incremento de la oferta de plazas en los últimos años, tanto en universidades públicas como privadas, y, consecuentemente, un aumento del número de egresados con dicho perfil académico/profesional. Dentro de las posibles salidas profesionales de estos titulados, se encuentra el acceso al Sistema Nacional de Salud. Para ello, los candidatos deben superar previamente las pruebas selectivas de acceso a plazas de formación sanitaria especializada, tras lo cual, aquellos que obtienen plaza, se incorporan al sistema de formación de posgrado en régimen de residencia (Psicólogo Interno Residente -PIR-. El presente trabajo analiza el rendimiento de los egresados de las distintas Facultades de Psicología españolas en las pruebas de acceso al Sistema Nacional de Salud durante el periodo 2013-2016, y las posibles diferencias en función de variables como el tamaño o la titularidad de las universidades. El carácter nacional de la convocatoria y la objetividad de las pruebas, hacen posible evaluar el impacto educativo y laboral de estas instituciones, incorporando al enfoque de la rendición de cuentas una dimensión social.

Differences in predators of artificial and real songbirds nests: Evidence of bias in artificial nest studies

Science.gov (United States)

Frank R. Thompson; Dirk E. Burhans

2004-01-01

In the past two decades, many researchers have used artificial nest to measure relative rates of nest predation. Recent comparisons show that real and artificial nests may not be depredated at the same rate, but no one has examined the mechanisms underlying these patterns. We determined differences in predator-specific predation rates of real and artificial nests. we...

Conservation significance of alternative nests of golden eagles

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Brian A. Millsap

2015-01-01

Full Text Available Golden eagles (Aquila chrysaetos are long-lived raptors that maintain nesting territories that may be occupied for a century or longer. Within occupied nesting territories there is one nest in which eagles lay their eggs in a given year (i.e., the used nest, but there are usually other nests (i.e., alternative nests. Conservation plans often protect used nests, but not alternative nests or nesting territories that appear vacant. Our objective is to review literature on golden eagle use of alternative nests and occupancy of nesting territories to determine if alternative nests are biologically significant and warrant greater conservation consideration. Our review shows that: (1 alternative nests or their associated habitat are most often in core areas of golden eagle nesting territories; (2 alternative nests likely will become used in the future; (3 probability of an alternative nest becoming used is greatest where prey availability is high and alternative nest sites are limited; (4 likelihood of annual occupancy or reoccupancy of golden eagle nesting territories is high; and (5 prey availability is the most important determinant of nesting territory occupancy and breeding activity. We recommend alternative nests be treated with the same deference as used nests in land use planning.

Neste Corporation - a successful year

International Nuclear Information System (INIS)

Ihamuotila, J.

1991-01-01

The past year proved a successful one for Neste Corporation. Profitability was good and operations were consistently developed. Neste is committed to giving high priority to productivity and know- how to ensure that this success continues into the future. Important developments affecting the structure of Neste Corporation during 1990 included the amalgamation of Neste's oil-related activities into a single division, the increasing concentration of Neste Chemicals, activities in Central and Southern Europe and a major strengthening of oil exploration and production operations. Neste Oil turned in a good result during 1990. Neste imported a total of 8.9 million tonnes of crude oil during 1990. Imports from the Soviet Union at 5.2 million tonnes, were over 2 million tonnes less than planned. Some 2.5 million tonnes were imported from the North Sea, and 1.2 million tonnes from the Middle East. The year was one of expansion, diversification, and solid profit for Neste Chemicals. Net sales grew by 18 % compared to 1989 and the division recorded a satisfactory performance. Petrochemicals and polyolefins production increased suhstantially as a result of plants completed, acquired, or leased during 1989. The gas division's net sales during 1990 were 46 % higher than during 1989. This growth largely resulted from an increase in the consumption of natural gas and an expansion in the volume of international IPG business. The division's profitability remained satisfactory

Columbia River ESI: NESTS (Nest Points)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for bird nesting sites in the Columbia River area. Vector points in this data set represent locations of...

La prueba de decisión léxica como herramienta para ubicar al estudiante de español en los programas universitarios

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Marta Fairclough

2009-04-01

Full Text Available La prueba de decisión léxica ha demostrado ser una medida práctica para medir la habilidad global en un idioma. El presente estudio intenta medir cuán efectiva resulta la prueba de decisión léxica con dos grupos de estudiantes universitarios bilingües en inglés y español, pertenecientes a cuatro niveles diferentes. Para diseñar la prueba se utilizó un diccionario de frecuencia del español (Davies, 2006. En una lista de doscientos ítemes, que incluía palabras reales e inventadas, los participantes marcaron solamente aquellas cuyo significado conocían. A modo de comparación se usó un cloze-test. Los resultados de este estudio piloto muestran una alta correlación entre las dos medidas y sugieren que la prueba de decisión léxica resulta ser una herramienta de evaluación válida, económica, fácil de administrar y de corregir.

Las chicas en PISA y el marcado de casillas. Un examen de la perspectiva de los estudiantes sobre las pruebas PISA

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Gerry Mac Ruairc

2013-01-01

Full Text Available El artículo se mueve desde el análisis a nivel macro a la perspectiva de los estudiantes en las pruebas PISA. Mientras que está empíricamente bien establecido el alto nivel de correlación entre el nivel educativo y el nivel socioeconómico de los estudiantes, en este estudio el autor pretende analizar cómo los estudiantes socio-económicamente desfavorecidos reaccionan a las pruebas y participan en el proceso. Para ello, es importante tener en cuenta los puntos de vista de los propios estudiantes. Al examinar los puntos de vista de los estudiantes en las pruebas de PISA en un estudio de caso, el autor ofrece una visión de cómo un grupo de chicas de clase trabajadora, procedente de una escuela de un área urbana desfavorecida, experimentó en la evaluación PISA (2009 en la República de Irlanda. El análisis temático de las entrevistas y las transcripciones a los grupos focales revelaron dos cuestiones: para la mayoría de los estudiantes, pero especialmente para aquellos con necesidades educativas especiales, se sintieron estresados por el contenido y la dificultad de los ítems; por su parte, los estudiantes se limitaban simplemente a los requisitos exigidos de completar la prueba en el tiempo establecido, con sus implicaciones para su validez. Se concluye con la necesidad de un enfoque más proactivo de apoyo a los estudiantes y un modelo más matizado de la evaluación en las futuras pruebas PISA para tener en cuenta las diferencias de clase social.

Diseño de un equipo de pruebas rápidas para aceites usados

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Juan Carlos Delgado Sanabria

2016-01-01

Full Text Available El presente trabajo tiene como objetivo presentar el proceso de diseño y la construcción de un equipo de pruebas rápidas para el análisis de aceites usados de motores. El equipo que permite evaluar el estado de degradación y contaminación de una muestra de aceite usado mediante los ensayos de crepitación, mancha de aceite, viscosidad y contenido de partículas consta de cuatro aparatos: placa de calentamiento, generador de manchas, viscosímetro de caída de bolas y detector de partículas ferrosas. El aporte fundamental del trabajo lo constituyen los dispositivos y métodos ideados tanto para medir con exactitud el tiempo de caída de la esfera del viscosímetro de bolas como para la detección de partículas ferromagnéticas. El equipo ha producido resultados satisfactorios comparados con los obtenidos en pruebas de laboratorio.

Changes in position and quality of preferred nest box: effects on nest box use by laying hens

DEFF Research Database (Denmark)

Riber, Anja Brinch; Nielsen, Birte L.

2013-01-01

Using laying hens, we investigated whether position of a nest box, both within the pen and relative to other nest boxes, influenced the preference for a nest box, and how a sudden and marked change to the preferred box influenced the use of nest boxes by the hens. Groups (n=12) of 15 Isa Warren...... hens were housed in pens, each with five identical nest boxes in different positions: Two single (in a corner or not) and a triplet of nest boxes (one of which in a corner). The use of nest boxes was determined by the number of eggs laid daily in each box. Three experiments, each lasting 10 days, were...... carried out. First, the undisturbed use of each of the nest box types was investigated, and a strong preference (Peggs laid there. Second, each of the hen groups was moved to another pen allocated at random, and where...

Advances in diagnostic tests for bacterial STDs Avances en las pruebas diagnósticas de ETS bacterianas

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Stephen A Morse

2003-01-01

Full Text Available Because of their asymptomatic nature and nonspecific symptoms, laboratory tests are often required to diagnose a sexually transmitted infection. Over the past few years, there have been advances in technology, such as the development of nucleic acid amplification assays, which have improved our ability to diagnose infections caused by Chlamydia trachomatis. The finding that nucleic acid amplification tests can detect more infected individuals and are useful in screening low prevalence populations, has led to the development of strategies designed to reduce the cost of these assays without significantly impacting their sensitivity. The development of new tests for the diagnosis of syphilis has gained momentum from the report of a synthetic VDRL antigen, which will result in better nontreponemal antibody tests for syphilis. In spite of the completion of the genome sequence of Treponema pallidum and its annotation, we are still unable to cultivate this microorganism in vitro. However, the molecular revolution has resulted in the development of PCR assays for detecting Treponema pallidum in various types of clinical specimens, and to the production of recombinant antigens for use in tests that detect treponemal-specific antibodies. Further research will improve the availability of low cost, sensitive tests for the diagnosis of sexually transmitted infections.Las pruebas de laboratorio son necesarias a menudo para el diagnóstico de las infecciones transmitidas sexualmente, debido a la naturaleza asintomática o a la presencia de síntomas inespecíficos de esas infecciones. En este sentido, durante los años relativamente recientes se han registrado importantes avances tecnológicos, como por ejemplo los ensayos de amplificación de ácidos nucleicos que han permitido una mejora en la posibilidad de diagnosticar las infecciones causadas por Chlamydia trachomatis. El descubrimiento de que las pruebas de amplificación de ácidos nucleicos permiten

Valoración de pruebas diagnósticas de desnutrición en pacientes adultos, Hospital IESS, Cuenca 2014

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Tannia Elizabeth Quiroga Torres

2016-12-01

Full Text Available Introducción: La desnutrición hospitalaria no es una realidad nueva, pero en los últimos años ha ido adquiriendo mayor relevancia como resultado de los avances médicos. Objetivo: Valorar las pruebas diagnósticas de desnutrición en pacientes adultos ingresados en el Hospital del Instituto Ecuatoriano de Seguridad Social en la ciudad de Cuenca, de enero a agosto de 2014. Métodos: Se realizó un estudio no experimental, observacional analítico de tipo transversal, durante los meses de enero a agosto de 2014. El universo estuvo formado por 138 pacientes internados con edades entre 18 a 72 años, con diagnóstico definido, historia clínica abierta y que firmaron el consentimiento informado. Se calculó la sensibilidad y especificidad en pruebas diagnósticas de desnutrición. Resultados: La Valoración Global Subjetiva diagnosticó desnutrición o riesgo de desnutrición en el 52% de los pacientes. El Mini Nutrictional Assesment fue de 48%. El Índice de Masa Corporal fue de 7,9% de desnutrición. El Área Muscular Corregida del Brazo fue de 36%. El Porcentaje de Masa Magra fue de 51% y la Circunferencia de la Pantorrilla fue de 7,2%. Se encontró hipoalbuminemia en el 31,8% de pacientes y linfopenia en el 32,4%. Ninguna de estas pruebas fue más sensible y específica que el gold estándar. Ocurrió asociación significativa entre el Mini Nutritional Asesment y el Área Muscular Corregida del Brazo. Conclusiones: Se halló que la VGS fue la prueba estándar para diagnóstico de desnutrición hospitalaria. La utilización de pruebas  diagnósticas sensibles y específicas sería útil en la toma de medidas respectivas a la intervención, así como para evitar complicaciones hacia la enfermedad base.

Factores Asociados a la realización de una prueba de detección de VIH en estudiantes universitarios.

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Cindy Alcarraz

2008-01-01

Full Text Available Objetivo: Determinar factores asociados a la realización de la prueba de detección de infección por VIH en estudiantes de la Universidad Nacional Mayor San Marcos (UNMSM. Diseño: Estudio transversal. Lugar: Campus Universitario, Facultad de Medicina Veterinaria, Facultad de Medicina. Participantes: Estudiantes regulares de pregrado de la UNMSM en el periodo 2008-I. Intervenciones: Cuestionario estructurado de 63 ítems, realizándose un muestreo no probabilístico por conveniencia. Se aplicaron los programas SPSS v.15.0 para Windows® y EpiDat v.3.1. Principales medidas de resultados: Frecuencias de las variables de estudio y Odds Ratio con IC al 95%. Resultados: Se encuestó a 368 estudiantes (59,3% varones y 40,7% mujeres. El 54,4% ya había iniciado su vida sexual; 49,5% de éstos, antes de los 18 años. Sólo 33 (9% afirmaron haberse realizado anteriormente una prueba de detección de infección por VIH, mientras que 310 (84,2% la consideraron necesaria. Los hombres mostraron mayor probabilidad de someterse a la prueba diagnóstica de infección por VIH en comparación a las mujeres (OR: 2.77, IC 95%: 1.17-6.55. Se encontró relación con el hecho de haberse sometido anteriormente a la prueba de VIH, en aquellos que ya han iniciado su vida sexual y en los que han tenido 5 o más parejas sexuales (OR: 3.44, IC 95%: 1.45-8.14; OR: 3.03, IC 95%: 1.14-8.09, en comparación a los que aún no han tenido relaciones sexuales, y a los que han tenido 1 o 2 parejas, respectivamente. Conclusión: Los factores que se asociaron a mayor probabilidad de realizarse la prueba de VIH fueron la vida sexual activa y el número elevado de parejas sexuales.

DECLARACIÓN DE LA PARTE COMO MEDIO DE PRUEBA Party as witness

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Felipe Marín Verdugo

2010-01-01

Full Text Available Los procedimientos judiciales chilenos han sufrido importantes cambios en las últimas dos décadas. Han transitado desde un sistema escrito a uno por audiencias. Esto ha significado un nuevo diseño de la audiencia de juicio y en particular, de las reglas de la prueba. El alcance de estos cambios no es aun totalmente comprendido, lo que permite la sobrevivencia de algunas prácticas del sistema escrito anterior dentro del nuevo. Este trabajo identifica una de ellas, que consiste en la exclusión de las partes como testigos en sus propios juicios. Se explicará cuál fue el fundamento de esta exclusión en el sistema escrito anterior y cómo éste ha sido superado en varios ordenamientos comparados. Se sostendrá que en el contexto de los nuevos sistemas por audiencias chilenos, en los que el juez debe valorar la prueba en concreto, dicha exclusión carece de sentido y las partes deben ser admitidas para declarar voluntariamente. Se sostendrá también que las nuevas reglas de la prueba lo permiten, analizándolas pormenorizadamente. Asimismo se contestará a los argumentos esgrimidos para justificar la mantención de esta exclusión y finalmente, se propondrá una manera de rendir la declaración de la parte como testigo en conformidad a las nuevas reglas de la prueba.During the last two decades, the Chilean judicial procedures have undergone an important reform process. It went from a written procedure to a hearing-based procedure. This change involved a new design for the trial hearing and, in particular, for the rules of evidence. The meaning of these changes is not yet well understood, making it easier for the survival of former practices of the written system within the new hearing-based system. This paper identifies on of them, which is the exclusion of parties as witnesses. The paper explains the reasons of the origin of this rule of exclusion in the former written procedure and how it was subsequently overcome in several comparative

The influence of regional hydrology on nesting behavior and nest fate of the American alligator

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Ugarte, Cristina A.; Bass, Oron L.; Nuttle, William; Mazzotti, Frank J.; Rice, Kenneth G.; Fujisaki, Ikuko; Whelan, Kevin R.T.

2013-01-01

Hydrologic conditions are critical to the nesting behavior and reproductive success of crocodilians. In South Florida, USA, growing human settlement has led to extensive surface water management and modification of historical water flows in the wetlands, which have affected regional nesting of the American alligator (Alligator mississippiensis). Although both natural and anthropogenic factors are considered to determine hydrologic conditions, the aspects of hydrological patterns that affect alligator nest effort, flooding (partial and complete), and failure (no hatchling) are unclear. We deconstructed annual hydrological patterns using harmonic models that estimated hydrological matrices including mean, amplitude, timing of peak, and periodicity of surface water depth and discharge and examined their effects on alligator nesting using survey data from Shark Slough, Everglades National Park, from 1985 to 2005. Nest effort increased in years with higher mean and lesser periodicity of water depth. A greater proportion of nests were flooded and failed when peak discharge occurred earlier in the year. Also, nest flooding rates were greater in years with greater periodicity of water depth, and nest failure rate was greater when mean discharge was higher. This study guides future water management decisions to mitigate negative impacts on reproduction of alligators and provides wildlife managers with a tool for assessing and modifying annual water management plans to conserve crocodilians and other wetland species.

Lack of nest site limitation in a cavity-nesting bird community

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Jeffry R. Waters; Barry R. Noon; Jared Verner

1990-01-01

We examined the relationship between nest site availability and density of secondary cavitynesting birds by blocking cavities in an oak-pine (Quercus spp.-Pinus sp. ) woodland. In 1986 and 1987we blocked 67 and 106 cavities, respectively, on a 37-ha plot. The combined density of secondary cavity-nesting birds did not decline...

Nesting biology of Trypoxylon (Trypargilum) lactitarse Saussure (Hymenoptera, Crabronidae) in trap-nests in Southern Brazil.

Science.gov (United States)

Buschini, M L T; Niesing, F; Wolff, L L

2006-08-01

This study was carried in the Parque Municipal das Araucárias in the municipality of Guarapuava, state of Paraná, Southern Brazil. Three hundred and sixty five nests of T. lactitarse were obtained using trap-nests of 0.7, 1.0, and 1.3 cm in diameter. All of them had similar architecture, regardless of the diameter of the trap-nest. Completed nests consisted of a linear series of brood cells whose average number per nest was of 3.3, 4.0 and 3.6 for the nests with 0.7 cm, 1.0 cm and 1.3 cm in diameter, respectively. They were constructed more often during the summer. T. lactitarse had two types of life cycles: direct development (without diapause), and delayed development (with diapause during winter). Natural enemies included Chrysididae, Sarcophagidae, Dolichopodidae and Ichneumonidae. Out of 1,353 identified spider prey, 1,313 belonged to the Araneidae family.

Nesting biology of Trypoxylon (Trypargilum lactitarse Saussure (Hymenoptera, Crabronidae in trap-nests in Southern Brazil

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M. L. T. Buschini

Full Text Available This study was carried in the Parque Municipal das Araucárias in the municipality of Guarapuava, state of Paraná, Southern Brazil. Three hundred and sixty five nests of T. lactitarse were obtained using trap-nests of 0.7, 1.0, and 1.3 cm in diameter. All of them had similar architecture, regardless of the diameter of the trap-nest. Completed nests consisted of a linear series of brood cells whose average number per nest was of 3.3, 4.0 and 3.6 for the nests with 0.7 cm, 1.0 cm and 1.3 cm in diameter, respectively. They were constructed more often during the summer. T. lactitarse had two types of life cycles: direct development (without diapause, and delayed development (with diapause during winter. Natural enemies included Chrysididae, Sarcophagidae, Dolichopodidae and Ichneumonidae. Out of 1,353 identified spider prey, 1,313 belonged to the Araneidae family.

Nest design in a changing world: great tit Parus major nests from a Mediterranean city environment as a case study.

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Lambrechts, Marcel M; Charmantier, Anne; Demeyrier, Virginie; Lucas, Annick; Perret, Samuel; Abouladzé, Matthieu; Bonnet, Michel; Canonne, Coline; Faucon, Virginie; Grosset, Stéphanie; le Prado, Gaëlle; Lidon, Frédéric; Noell, Thierry; Pagano, Pascal; Perret, Vincent; Pouplard, Stéphane; Spitaliéry, Rémy; Bernard, Cyril; Perret, Philippe; Blondel, Jacques; Grégoire, Arnaud

2017-12-01

Investigations of urbanization effects on birds have focused mainly on breeding traits expressed after the nest-building stage (e.g. first-egg date, clutch size, breeding success, and offspring characteristics). Urban studies largely ignored how and why the aspects of nest building might be associated with the degree of urbanization. As urban environments are expected to present novel environmental changes relative to rural environments, it is important to evaluate how nest-building behavior is impacted by vegetation modifications associated with urbanization. To examine nest design in a Mediterranean city environment, we allowed urban great tits ( Parus major ) to breed in nest boxes in areas that differed in local vegetation cover. We found that different measures of nest size or mass were not associated with vegetation cover. In particular, nests located adjacent to streets with lower vegetation cover were not smaller or lighter than nests in parks with higher vegetation cover. Nests adjacent to streets contained more pine needles than nests in parks. In addition, in nests adjacent to streets, nests from boxes attached to pine trees contained more pine needles than nests from boxes attached to other trees. We suggest that urban-related alterations in vegetation cover do not directly impose physical limits on nest size in species that are opportunistic in the selection of nesting material. However, nest composition as reflected in the use of pine needles was clearly affected by habitat type and the planted tree species present, which implies that rapid habitat change impacts nest composition. We do not exclude that urbanization might impact other aspects of nest building behaviour not covered in our study (e.g. costs of searching for nest material), and that the strengths of the associations between urbanization and nest structures might differ among study populations or species.

Decoration Increases the Conspicuousness of Raptor Nests.

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Canal, David; Mulero-Pázmány, Margarita; Negro, Juan José; Sergio, Fabrizio

2016-01-01

Avian nests are frequently concealed or camouflaged, but a number of species builds noticeable nests or use conspicuous materials for nest decoration. In most cases, nest decoration has a role in mate choice or provides thermoregulatory or antiparasitic benefits. In territorial species however, decorations may serve additional or complementary functions, such as extended phenotypic signaling of nest-site occupancy and social status to potential intruders. The latter may benefit both signaler and receiver by minimizing the risk of aggressive interactions, especially in organisms with dangerous weaponry. Support for this hypothesis was recently found in a population of black kites (Milvus migrans), a territorial raptor that decorates its nest with white artificial materials. However, the crucial assumption that nest decorations increased nest-site visibility to conspecifics was not assessed, a key aspect given that black kite nests may be well concealed within the canopy. Here, we used an unmanned aircraft system to take pictures of black kite nests, with and without an experimentally placed decoration, from different altitudes and distances simulating the perspective of a flying and approaching, prospecting intruder. The pictures were shown to human volunteers through a standardized routine to determine whether detection rates varied according the nest decoration status and distance. Decorated nests consistently showed a higher detection frequency and a lower detection-latency, compared to undecorated versions of the same nests. Our results confirm that nest decoration in this species may act as a signaling medium that enhances nest visibility for aerial receivers, even at large distances. This finding complements previous work on this communication system, which showed that nest decoration was a threat informing trespassing conspecifics on the social dominance, territory quality and fighting capabilities of the signaler.

Nest defense behaviors of native cavity-nesting birds to European Starlings

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Rodney G. Olsen; Kathryn L. Purcell; David. Grubbs

2008-01-01

We used behavioral experiments to evaluate competition for nest sites and the extent to which European Starlings (Sturnus vulgaris) are seen as a threat by native bird species at the San Joaquin Experimental Range, Madera County, CA. We quantified the level of aggressive behavior of four species of native cavity-nesting birds to starlings at active...

Use of artificial nests to investigate predation on freshwater turtle nests

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Michael N. Marchand; John A. Litvaitis; Thomas J. Maier; Richard M. DeGraaf

2002-01-01

Habitat fragmentation has raised concerns that populations of generalist predators have increased and are affecting a diverse group of prey. Previous research has included the use of artificial nests to investigate the role of predation on birds that nest on or near the ground. Because predation also is a major factor limiting populations of freshwater turtles, we...

Interspecific nest use by aridland birds

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Deborah M. Finch

1982-01-01

Nest holes drilled by woodpeckers (Picidae) are frequently used by secondary cavity-nesting species, but interspecific use of open and domed nests is less well known. Nests constructed by many southwestern desert birds last longer than one year (pers. obs.) and are consequently reused by the same pair (e.g., Abert's Towhees [Pipilo aberti], pers. obs.) or by other...

Nesting biology of the trap-nesting Neotropical wasp Trypoxylo n(Trypargilum) aurifrons Shuckard (Hymenoptera, Crabronidae)

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Santoni,Mariana Marchi; Del Lama,Marco Antonio

2007-01-01

The present study was carried out in three localities of the state of São Paulo, Brazil: Araras (Dec/03-Dec/06), São Carlos (Nov/04-Nov/06) and Rifaina (Jul/04-Dec/06). Trap-nests were distributed among sites in the sampling areas and were collected every 35 days. Data from 295 nests indicate that T. aurifrons is a multivoltine species, with higher rates of nest building and cell production in the warm, rainy season. The trap-nests used by the females ranged from 117 to 467 mm in length and 3...

Preliminary evaluation of a nest usage sensor to detect double nest occupations of laying hens.

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Zaninelli, Mauro; Costa, Annamaria; Tangorra, Francesco Maria; Rossi, Luciana; Agazzi, Alessandro; Savoini, Giovanni

2015-01-26

Conventional cage systems will be replaced by housing systems that allow hens to move freely. These systems may improve hens' welfare, but they lead to some disadvantages: disease, bone fractures, cannibalism, piling and lower egg production. New selection criteria for existing commercial strains should be identified considering individual data about laying performance and the behavior of hens. Many recording systems have been developed to collect these data. However, the management of double nest occupations remains critical for the correct egg-to-hen assignment. To limit such events, most systems adopt specific trap devices and additional mechanical components. Others, instead, only prevent these occurrences by narrowing the nest, without any detection and management. The aim of this study was to develop and test a nest usage "sensor", based on imaging analysis, that is able to automatically detect a double nest occupation. Results showed that the developed sensor correctly identified the double nest occupation occurrences. Therefore, the imaging analysis resulted in being a useful solution that could simplify the nest construction for this type of recording system, allowing the collection of more precise and accurate data, since double nest occupations would be managed and the normal laying behavior of hens would not be discouraged by the presence of the trap devices.

Preliminary Evaluation of a Nest Usage Sensor to Detect Double Nest Occupations of Laying Hens

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Mauro Zaninelli

2015-01-01

Full Text Available Conventional cage systems will be replaced by housing systems that allow hens to move freely. These systems may improve hens’ welfare, but they lead to some disadvantages: disease, bone fractures, cannibalism, piling and lower egg production. New selection criteria for existing commercial strains should be identified considering individual data about laying performance and the behavior of hens. Many recording systems have been developed to collect these data. However, the management of double nest occupations remains critical for the correct egg-to-hen assignment. To limit such events, most systems adopt specific trap devices and additional mechanical components. Others, instead, only prevent these occurrences by narrowing the nest, without any detection and management. The aim of this study was to develop and test a nest usage “sensor”, based on imaging analysis, that is able to automatically detect a double nest occupation. Results showed that the developed sensor correctly identified the double nest occupation occurrences. Therefore, the imaging analysis resulted in being a useful solution that could simplify the nest construction for this type of recording system, allowing the collection of more precise and accurate data, since double nest occupations would be managed and the normal laying behavior of hens would not be discouraged by the presence of the trap devices.

Nest densities of cavity-nesting birds in relation to postfire salvage logging and time since wildfire

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Victoria A. Saab; Robin E. Russell; Jonathan G. Dudley

2007-01-01

We monitored the nest densities and nest survival of seven cavity-nesting bird species, including four open-space foragers (American Kestrel [Falco sparverius], Lewis's Woodpecker [Melanerpes lewis], Western Bluebird [Sialia mexicana], and Mountain Bluebird [S. currucoides]) and three wood...

Contrasting Effects of Cattle Grazing Intensity on Upland-Nesting Duck Production at Nest and Field Scales in the Aspen Parkland, Canada

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Jeffrey M. Warren

2008-12-01

Full Text Available The Aspen Parkland of Canada is one of the most important breeding areas for temperate nesting ducks in North America. The region is dominated by agricultural land use, with approximately 9.3 million ha in pasture land for cattle grazing. However, the effects of using land for cattle grazing on upland-nesting duck production are poorly understood. The current study was undertaken during 2001 and 2002 to investigate how nest density and nesting success of upland-nesting ducks varied with respect to the intensity of cattle grazing in the Aspen Parkland. We predicted that the removal and trampling of vegetation through cattle grazing would reduce duck nest density. Both positive and negative responses of duck nesting success to grazing have been reported in previous studies, leading us to test competing hypotheses that nesting success would (1 decline linearly with grazing intensity or (2 peak at moderate levels of grazing. Nearly 3300 ha of upland cover were searched during the study. Despite extensive and severe drought, nest searches located 302 duck nests. As predicted, nest density was higher in fields with lower grazing intensity and higher pasture health scores. A lightly grazed field with a pasture score of 85 out of a possible 100 was predicted to have 16.1 nests/100 ha (95% CI = 11.7-22.1, more than five times the predicted nest density of a heavily grazed field with a pasture score of 58 (3.3 nests/100 ha, 95% CI = 2.2-4.5. Nesting success was positively related to nest-site vegetation density across most levels of grazing intensity studied, supporting our hypothesis that reductions in vegetation caused by grazing would negatively affect nesting success. However, nesting success increased with grazing intensity at the field scale. For example, nesting success for a well-concealed nest in a lightly grazed field was 11.6% (95% CI = 3.6-25.0%, whereas nesting success for a nest with the same level of nest-site vegetation in a heavily grazed

Sesgos en estimación, tamaño y potencia de una prueba sobre el parámetro de memoria larga en modelos ARFIMA

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Elkin Castaño

2010-01-01

Full Text Available Castaño et al. (2008 proponen una prueba para investigar la existencia de memoria larga, basada en el parámetro de diferenciación fraccional de un modelo ARFIMA (p, d, q; se muestra que al usar una aproximación autorregresiva de orden igual al entero más próximo a p* = T1/3 para la componente de memoria corta, la prueba de la hipótesis nula de memoria corta contra la alternativa de memoria larga tiene, en general, mayor potencia que algunas otras pruebas conservando un tamaño adecuado. Este estudio muestra los sesgos generados en la estimación del parámetro d y su efecto sobre la potencia y tamaño de la prueba, cuando se ignora la componente de corto plazo y cuando se emplean modelos que no la aproximan adecuadamente. Adicionalmente, se analiza si los resultados obtenidos por Castaño et al. (2008 pueden mejorarse empleando una aproximación autorregresiva diferente.

Nesting ecology of Arctic loons

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Petersen, Margaret R.

1979-01-01

Arctic Loons were studied on the Yukon-Kuskokwim Delta, Alaska, from the time of their arrival in May to their departure in September, in 1974 and 1975. Pairs arrived on breeding ponds as soon as sufficient meltwater was available to allow their take-off and landing. Loons apparently do not initiate nests immediately after their arrival, even when nest-sites are available. Delayed egg-laying may be dependent on a period of yolk formation. Delaying yolk formation until after arrival on nest ponds is an adaptation by loons to the variable time suitable habitat becomes available for nesting. Predation of eggs by Glaucous Gulls, Long-tailed and Parasitic jaegers and foxes varied in relation to the location of the nest-site, and the availability of alternate prey. Hatching success was the lowest recorded for Arctic Loons (5%) in 1974, when eggs of both loons and Cackling Geese were taken in large numbers by predators. Hatching success increased to 32% in 1975 when an abundance of tundra voles was observed. No loon eggs hatched after the hatching of the Cackling Goose eggs when this alternate prey was no longer available. Nests destroyed by foxes were predominantly along shorelines, and those by gulls and jaegers were predominantly on islands. Nest-site selection by Arctic Loons may reflect an adaptive response to varying selective pressures by their predators.

Nest-site selection in the acorn woodpecker

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Hooge, P.N.; Stanback, M.T.; Koenig, Walter D.

1999-01-01

Acorn Woodpeckers (Melanerpes formicivorus) at Hastings Reservation in central California prefer to nest in dead limbs in large, dead valley oaks (Quercus lobata) and California sycamores (Platanus racemosa) that are also frequently used as acorn storage trees. Based on 232 nest cavities used over an 18-year period, we tested whether preferred or modal nest-site characters were associated with increased reproductive success (the "nest-site quality" hypothesis). We also examined whether more successful nests were likely to experience more favorable microclimatic conditions or to be less accessible to terrestrial predators. We found only equivocal support for the nest-site quality hypothesis: only 1 of 5 preferred characters and 2 of 10 characters exhibiting a clear modality were correlated with higher reproductive success. All three characteristics of nests known or likely to be associated with a more favorable microclimate, and two of five characteristics likely to render nests less accessible to predators, were correlated with higher reproductive success. These results suggest that nest cavities in this population are built in part to take advantage of favorable microclimatic conditions and, to a lesser extent, to reduce access to predators. However, despite benefits of particular nest characteristics, birds frequently nested in apparently suboptimal cavities. We also found a significant relationship between mean group size and the history of occupancy of particular territories and the probability of nest cavities being built in microclimatically favorable live limbs, suggesting that larger groups residing on more stable territories were better able to construct nests with optimal characteristics. This indicates that there may be demographic, as well as ecological, constraints on nest-site selection in this primary cavity nester.

Efectividad de las salidas frontal y lateral para la prueba de pista 300 metros CRI, patinaje de velocidad sobre ruedas

OpenAIRE

Bohórquez-Páez, Daniel A. A; Pinzón-Castro, Luis A; Obando-Bastidas, Jorge A

2014-01-01

Se analizó y evaluó biomecánicamente, desde el plano sagital izquierdo, la Salida Frontal (SF) y la Salida Lateral (SL) en pruebas de velocidad de pista Contra el Reloj Individual (CRI), de once (11) Patinadores de Velocidad Sobre Ruedas (VSR), empleando el Software SIMI°Twinner Pro y el software SPSS (versión 19); lo que permitió determinar que la SF es la más efectiva que la SL para el desarrollo de las pruebas CRI en el patinaje de VSR. We analyzed and evaluated biomechanically, from th...

Una prueba de razón de verosimilitudes para discriminar entre la distribución Poisson, Binomial y Binomial Negativa.

OpenAIRE

López Martínez, Laura Elizabeth

2010-01-01

En este trabajo se realiza inferencia estadística en la distribución Binomial Negativa Generalizada (BNG) y los modelos que anida, los cuales son Binomial, Binomial Negativa y Poisson. Se aborda el problema de estimación de parámetros en la distribución BNG y se propone una prueba de razón de verosimilitud generalizada para discernir si un conjunto de datos se ajusta en particular al modelo Binomial, Binomial Negativa o Poisson. Además, se estudian las potencias y tamaños de la prueba p...

Discriminación diagnóstica de las pruebas de predicción de la vía aérea difícil

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Cristina Mirabal Rodríguez

2003-06-01

Full Text Available Con el objetivo de determinar la validez pronóstica de las pruebas predictivas de la vía aérea difícil, se realizó un estudio observacional-descriptivo que involucró a todos los pacientes mayores de 15 años operados con anestesia general orotraqueal en condiciones electivas, en el Hospital Provincial General Docente "Antonio L. Luaces Iraola" de Ciego de Ávila, en un período de 1 año. A cada paciente se le aplicaron preoperatoriamente 3 pruebas predictivas de vía aérea difícil, a saber: la prueba de Mallampati, extensión atlantooccipital y distancia mentotiroidea. Luego de la inducción anestésica se le aplicó la última de estas pruebas que es la de visión directa (Cormack y Lehane. Se evaluó la capacidad discriminativa diagnóstica de cada una de estas pruebas. De las pruebas estudiadas la de visión directa resultó ser el mejor predictor de entubación difícil. Las pruebas diagnósticas de Mallampati, extensión atlantooccipital y distancia mentotiroidea tienen una baja sensibilidad y especificidad, así como poco valor predictivoIn order to determine the prognostic value of the difficult airways predictive tests, an observational and descriptive study of all patients over 15 operated on with general orotracheal anesthesia under elective conditions at "Antonio L. Luaces Iraola" Provincial General Teaching Hospital, in Ciego de Avila, in a one-year term, was conducted. 3 predictive tests of the difficult airways were preoperatively applied to each patient: Mallampati's test, atlanto-occipital extension and mentothyroid distance., The last of these tests, which is that of direct vision (Cormack and Lehane was used after the anesthesia induction. The discriminatory diagnositc capacity of each of these tests was evaluated. Among the studied tests, the direct vision test proved to be the best predictor of difficult entubation. The diagnostic tests of Mallampati, atlantoocipital extension and mentothyroid distance have low

Nest-site competition between invasive and native cavity nesting birds and its implication for conservation.

Science.gov (United States)

Charter, Motti; Izhaki, Ido; Ben Mocha, Yitzchak; Kark, Salit

2016-10-01

Nesting cavities are often a limited resource that multiple species use. There is an ongoing discussion on whether invasive cavity nesting birds restrict the availability of this key limited resource. While the answer to this question has important conservation implications, little experimental work has been done to examine it. Here, we aimed to experimentally test whether alien cavity nesting birds affect the occupancy of cavities and the resulting breeding success of native cavity breeders in a large urban park located in Tel Aviv, Israel. Over three breeding seasons, we manipulated the entry size of nest boxes and compared the occupancy and breeding success of birds in nest boxes of two treatments. These included nest boxes with large-entrance and small-entrance holes. The large-entrance holes allowed access for both the native and invasive birds (the two main aliens in the park are the common mynas and rose-ringed parakeets). The smaller-entrance boxes, on the other hand, allowed only the smaller sized native cavity breeders (great tits and house sparrows) to enter the boxes but prevented the alien species from entering. We found that the large-entrance nest boxes were occupied by five different bird species, comprising three natives (great tit, house sparrow, Scops owl) and two invasive species (common myna, rose-ringed parakeet) while the small-entrance boxes were only occupied by the two native species. The alien common mynas and rose-ringed parakeets occupied 77.5% of the large-entrance nest boxes whereas native species, mainly great tits, occupied less than 9% of the large-entrance boxes and 36.5% of the small-entrance boxes. When examining the occupancy of those cavities that were not occupied by the aliens, natives occupied both the small and large-entrance nest boxes equally. Three quarters (78%) of the great tits breeding in the large-entrance boxes were usurped by common mynas during the breeding season and as a result breeding success was

Where to nest? Ecological determinants of chimpanzee nest abundance and distribution at the habitat and tree species scale.

Science.gov (United States)

Carvalho, Joana S; Meyer, Christoph F J; Vicente, Luis; Marques, Tiago A

2015-02-01

Conversion of forests to anthropogenic land-uses increasingly subjects chimpanzee populations to habitat changes and concomitant alterations in the plant resources available to them for nesting and feeding. Based on nest count surveys conducted during the dry season, we investigated nest tree species selection and the effect of vegetation attributes on nest abundance of the western chimpanzee, Pan troglodytes verus, at Lagoas de Cufada Natural Park (LCNP), Guinea-Bissau, a forest-savannah mosaic widely disturbed by humans. Further, we assessed patterns of nest height distribution to determine support for the anti-predator hypothesis. A zero-altered generalized linear mixed model showed that nest abundance was negatively related to floristic diversity (exponential form of the Shannon index) and positively with the availability of smaller-sized trees, reflecting characteristics of dense-canopy forest. A positive correlation between nest abundance and floristic richness (number of plant species) and composition indicated that species-rich open habitats are also important in nest site selection. Restricting this analysis to feeding trees, nest abundance was again positively associated with the availability of smaller-sized trees, further supporting the preference for nesting in food tree species from dense forest. Nest tree species selection was non-random, and oil palms were used at a much lower proportion (10%) than previously reported from other study sites in forest-savannah mosaics. While this study suggests that human disturbance may underlie the exclusive arboreal nesting at LCNP, better quantitative data are needed to determine to what extent the construction of elevated nests is in fact a response to predators able to climb trees. Given the importance of LCNP as refuge for Pan t. verus our findings can improve conservation decisions for the management of this important umbrella species as well as its remaining suitable habitats. © 2014 Wiley Periodicals, Inc.

Ant colonies prefer infected over uninfected nest sites

DEFF Research Database (Denmark)

Pontieri, Luigi; Vojvodic, Svjetlana; Graham, Riley

2014-01-01

with sporulating mycelium of the entomopathogenic fungus Metarhizium brunneum (infected nests), nests containing nestmates killed by freezing (uninfected nests), and empty nests. In contrast to the expectation pharaoh ant colonies preferentially (84%) moved into the infected nest when presented with the choice...... the high risk of epidemics in group-living animals. Choosing nest sites free of pathogens is hypothesized to be highly efficient in invasive ants as each of their introduced populations is often an open network of nests exchanging individuals (unicolonial) with frequent relocation into new nest sites...... and low genetic diversity, likely making these species particularly vulnerable to parasites and diseases. We investigated the nest site preference of the invasive pharaoh ant, Monomorium pharaonis, through binary choice tests between three nest types: nests containing dead nestmates overgrown...

Serenbe Nest Cottages

Energy Technology Data Exchange (ETDEWEB)

Butler, T.; Curtis, O.; Kim, E.; Roberts, S.; Stephenson, R.

2012-12-01

As part of the NAHB Research Center Industry Partnership, Southface partnered with Martin Dodson Builders and the Serenbe community on the construction of a new test home in the suburbs of Atlanta, GA in the mixed humid climate zone. The most recent subdivision within the Serenbe community, the Nest, will contain 15 small footprint cottage style homes, and Southface has selected Lot Nine, as the test home for this study. This Nest subdivision serves as a project showcase for both the builder partner and the Serenbe community as a whole. The planning and design incorporated into the Nest cottages will be implemented in each home within the subdivision. These homes addresses Building America Savings targets and serve as a basis of design for other homes Martin Dodson plans to build within the Serenbe community.

Serenbe Nest Cottages

Energy Technology Data Exchange (ETDEWEB)

Butler, T. [NAHB Research Center Industry Partnership, Upper Marlboro, MD (United States); Curtis, O. [NAHB Research Center Industry Partnership, Upper Marlboro, MD (United States); Kim, E. [NAHB Research Center Industry Partnership, Upper Marlboro, MD (United States); Roberts, S. [NAHB Research Center Industry Partnership, Upper Marlboro, MD (United States); Stephenson, R. [NAHB Research Center Industry Partnership, Upper Marlboro, MD (United States)

2012-12-01

As part of the NAHB Research Center Industry Partnership, Southface partnered with Martin Dodson Builders and the Serenbe community on the construction of a new test home in the suburbs of Atlanta, GA, in the mixed humid climate zone. The most recent subdivision within the Serenbe community, the Nest, will contain 15 small footprint cottage-style homes, and Southface has selected Lot Nine, as the test home for this study. This Nest subdivision serves as a project showcase for both the builder partner and the Serenbe community as a whole. The planning and design incorporated into the Nest cottages will be implemented in each home within the subdivision. These homes addresses Building America savings targets and serve as a basis of design for other homes Martin Dodson plans to build within the Serenbe community.

Conservation significance of alternative nests of golden eagles

Science.gov (United States)

Brian A. Millsap; Teryl G. Grubb; Robert K. Murphy; Ted Swem; James W. Watson

2015-01-01

Golden eagles (Aquila chrysaetos) are long-lived raptors that maintain nesting territories that may be occupied for a century or longer. Within occupied nesting territories there is one nest in which eagles lay their eggs in a given year (i.e., the used nest), but there are usually other nests (i.e., alternative nests). Conservation plans often protect used nests, but...

Nesting of the Blakiston's Fish-Owl in the Nest of the Steller’s Sea Eagle, Magadan Region, Russia

Directory of Open Access Journals (Sweden)

Irina G. Utekhina

2016-04-01

Full Text Available In 2015 one Steller’s Sea Eagle nest was occupied by a Blakiston’s Fish Owl, the first record of which came from the Nature Reserve Inspector, E.A. Stepanov, who, on May 17, noted the pair of fish owls near a Steller’s Sea Eagle nest on the western bank of the Chelomdja River, 3 km downstream from the Moldot ranger’s station. On that date one of the owls was sitting in the nest, and another was sitting in a tree nearby the nest. On May 26, E. Stepanov observed the owls in the same position. We observed the nest on 20 and 21 June 2015, and saw one large Blakiston’s Fish Owl chick in the nest; no adults were noted. Inspector A. Stepanov saw the chick in the nest on June 23, and an adult in a nearby.  Magadan State Reserve Inspector A. Akhanov reported that the nest was empty and no adults were seen on June 25.

Pruebas de vigor y calidad fisiológica de semillas de soja Vigor tests and physiological quality of soybean seeds

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Adriana Rita Salinas

2001-02-01

Full Text Available El objetivo de este trabajo fue estudiar las alteraciones producidas por el deterioro en semillas de soja (Glycine max L. Merrill utilizando diferentes pruebas de vigor. Se utilizaron semillas de soja de diferentes cultivares en 1997 y 1998, las cuales fueron sometidas a la prueba de germinación y diferentes pruebas de vigor: envejecimiento acelerado; conductividad eléctrica; deterioro controlado y tetrazolio. El deterioro controlado en semillas con 22% de humedad mostró ser un mejor indicador de la disminución del vigor de la semilla de soja que el envejecimiento acelerado. La conductividad eléctrica en semillas individuales podría ser considerada una buena prueba de vigor para detectar alteraciones producidas en las membranas citoplasmáticas en un estadio temprano del deterioro de las semillas. La clasificación de la viabilidad y el vigor a través de la prueba de tetrazolio está dada por el lugar donde se produce el daño y no por el tipo de daño que sufre la semilla.The objective of this work was to study soybean (Glycine max L. Merrill seed alterations produced by deterioration using different vigor tests. Soybean seeds of different cultivars were used in 1997 and 1998, which were submitted to standard germination test and the vigor tests: accelerated aging; electric conductivity; controlled deterioration and tetrazolium. The controlled deterioration with an elevation of the seed humidity to 22%, showed to be a better indicator of the diminishing of soybean seed vigor than the accelerated aging. The electric conductivity in individual seeds would be considered a good vigor test to detect the alterations produced in the cytoplasmic membranes in an early stage of the seed deterioration. The tetrazolium test by the evaluation of the different kinds of injuries suffered by the seeds, depends on the place where the seed is damaged not on the kind of injury suffered by the seed.

Intervalos de confianza y pruebas de hipótesis : una comparación entre dos métodos para estimación de parámetros

OpenAIRE

Giorgini, H. J.; Garsd, Armando

1998-01-01

p.191-198 Las dos formas más usuales de inferencia estadística son la estimación a través de intervalos de confianza y las pruebas de hipótesis. Ambas formas de inferencia permiten llegar a conclusiones similares. Sin embargo, se observa en el ambiente científico una sobrevaluación del alcance de las pruebas de hipótesis, mientras que los intervalos de confianza tienen la imagen de una herramienta rudimentaria. El valor p, resultante de una prueba de hipótesis, puede ser de gran utilidad c...

Nest site selection by Kentish plover suggests a trade-off between nest-crypsis and predator detection strategies.

Directory of Open Access Journals (Sweden)

Miguel Ángel Gómez-Serrano

Full Text Available Predation is one of the main causes of adult mortality and breeding failure for ground-nesting birds. Micro-habitat structure around nests plays a critical role in minimizing predation risk. Plovers nest in sites with little vegetation cover to maximize the incubating adult visibility, but many studies suggest a trade-off between nest-crypsis and predator detection strategies. However, this trade-off has not been explored in detail because methods used so far do not allow estimating the visibility with regards to critical factors such as slope or plant permeability to vision. Here, we tested the hypothesis that Kentish plovers select exposed sites according to a predator detection strategy, and the hypothesis that more concealed nests survive longer according to a crypsis strategy. To this end, we obtained an accurate estimation of the incubating adult's field of vision through a custom built inverted periscope. Our results showed that plovers selected nest sites with higher visibility than control points randomly selected with regards to humans and dogs, although nests located in sites with higher vegetation cover survived longer. In addition, the flushing distance (i.e., the distance at which incubating adults leave the nest when they detect a potential predator decreased with vegetation cover. Consequently, the advantages of concealing the nest were limited by the ability to detect predators, thus indirectly supporting the existence of the trade-off between crypsis and predator detection. Finally, human disturbance also constrained nest choice, forcing plovers to move to inland sites that were less suitable because of higher vegetation cover, and modulated flushing behavior, since plovers that were habituated to humans left their nests closer to potential predators. This constraint on the width of suitable breeding habitat is particularly relevant for the conservation of Kentish Plover in sand beaches, especially under the current context of

Strong selection on mandible and nest features in a carpenter bee that nests in two sympatric host plants

OpenAIRE

Flores-Prado, Luis; Pinto, Carlos F; Rojas, Alejandra; Fontúrbel, Francisco E

2014-01-01

Host plants are used by herbivorous insects as feeding or nesting resources. In wood-boring insects, host plants features may impose selective forces leading to phenotypic differentiation on traits related to nest construction. Carpenter bees build their nests in dead stems or dry twigs of shrubs and trees; thus, mandibles are essential for the nesting process, and the nest is required for egg laying and offspring survival. We explored the shape and intensity of natural selection on phenotypi...

Efectos del olvido dirigido con el método de las palabras: una comparación entre pruebas directas e indirectas de memoria

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Emiliano Díez

2000-01-01

Full Text Available En el presente estudio se analizaron los efectos del olvido dirigido en pruebas directas (reconocimiento y recuerdo e indirectas (categorización y detección de letras. Los resultados mostraron que las palabras marcadas para aprender se recordaban mejor y se reconocían más rápido y con mayor precisión que las marcadas para olvidar. Este patrón de resultados se replicó con la prueba de categorización. Sin embargo, no se encontró olvido dirigido en la prueba de detección de letras. Los resultados se discuten en función de la hipótesis basada en el repaso diferencial como mecanismo implicado en el olvido dirigido con el método de las palabras.

Rendimiento cognitivo de adolescentes con VIH en pruebas para la exploración de la flexibilidad mental

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Mariana Pino Melgarejo

2015-01-01

Full Text Available El VIH provoca alteraciones de la flexibilidad mental, cuyo carácter devastador aumenta cuanto más temprano el individuo haya sido contagiado. Por ello, en este artículo de investigación científica, se analiza comparativamente la ejecución en tests de flexibilidad mental de 30 sujetos positivos al VIH y 30 sujetos normales, con edades de 12 a 14 años. Como pruebas de flexibilidad mental se utilizaron el Trail Making Test y el Test de Series Gráficas Alternantes. Para el análisis de datos, se utilizaron pruebas de estadística descriptiva y la prueba T de Student. Los resultados muestran que en ambos test, los sujetos seropositivos rinden sobre lo patológico, en tanto los sanos rinden normal, al margen de la variabilidad interindividual. Abstract Taking into consideration that Human Immunodefiency Virus (VIH affect mental flexibility as earlier an individual have been infected with the virus, this research article aims to analyze and compare mental flexibility in 30 individuals with Human Immunodeficiency Virus (VIH aged between 12 and 14 and 30 individuasl without virus. Trail Making Test and Graphical Alternant Series Test were applied and in order to analyze the data descriptive statistic tests were used. Results showed seropositive individual perform normal compared with those ones with VIH within individual variability.

Habitat structure and diversity influence the nesting success of an endangered large cavity-nesting bird, the Southern Ground-hornbill

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Leigh Combrink

2017-11-01

Full Text Available Habitat features can have a profound effect on the nesting success of birds. Savannas are often managed with predators and large herbivores as priority species, with little thought to the many bird species that management decisions could affect. Using a data set spanning seven breeding seasons, we examined how nesting success of Southern Ground-hornbills (SGHs Bucorvus leadbeateri in the Kruger National Park varied as a result of various environmental and habitat factors within a radius of 3 km surrounding the nest site. Identifying which factors affect nesting success will allow for targeted management efforts to ensure the long-term survival of SGHs both within and outside of protected areas. Habitat structure and diversity of the vegetation surrounding the nest were the most influential factors on SGH nesting success. SGHs require open grassy areas for foraging and areas with large trees for nesting. Savanna habitat drivers such as elephants and fire should be managed to ensure that sufficient large trees are able to establish in the landscape and to control for bush encroachment. This is especially important in areas earmarked for SGH reintroductions. Nest sites of SGHs should be monitored to mitigate any structural changes in the habitat surrounding the nests. Nests should be modified or artificial nest sites provided, where nests have been damaged or lost, to ensure the continued presence of these birds in African savannas. Conservation implications: Habitat structure and diversity surrounding Southern Groundhornbill nests has a significant impact on their nesting success. This highlights the importance of monitoring vegetation change in savanna habitats where they occur. Management of savanna areas should take factors that influence bush encroachment, such as fire and elephants, into account to ensure the long-term persistence of these birds.

Correlación de la respuesta a antígenos de Mycobacterium tuberculosis y la prueba cutánea de tuberculina en pacientes con artritis reumatoide

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Yurika López

2013-06-01

Full Text Available Introducción. Los pacientes con artritis reumatoide bajo tratamiento con anti-TNFα están en alto riesgo de desarrollar tuberculosis activa, por lo cual se recomienda hacer la tamización para infección latente de tuberculosis, antes de iniciar el tratamiento. Objetivo. Comparar la prueba de tuberculina y la producción de IFNγ inducida por antígenos CFP (Culture Filtrate Protein y antígenos específicos de Mycobacterium tuberculosis (CFP-10 para el diagnóstico de infección latente de tuberculosis en pacientes con artritis reumatoide. Materiales y métodos. Se llevó a cabo un estudio transversal analítico en pacientes con artritis reumatoide atendidos en el Hospital Universitario San Vicente Fundación, entre enero y diciembrede 2007, a los cuales se les determinó la producción de IFNγ en respuesta a CFP y CFP-10 en sobrenadantes de cultivos de sangre total, y se correlacionó con la reacción en la prueba de tuberculina. Además, se estableció el grado de concordancia entre ambas pruebas. Resultados. Se incluyeron 45 pacientes, de los cuales, 14 (31,1 % tuvieron un diámetro de induración≥10 mm (tuberculina positiva, nueve (20 % produjeron IFNγ en respuesta a CFP-10, y siete fueron positivos para ambas pruebas. La correlación entre las pruebas fue de r=0,53 (IC95%: 0,28-0,72 y la concordancia global entre pruebas fue de 80 %, con un coeficiente kappa de 0,48 (IC95%: 0,20-0,76. Conclusiones. Solo se observaron dos pacientes con tuberculina positiva y CFP-10 positivo “anérgicos”y se encontraron seis pacientes con tuberculina positiva y CFP-10 negativa “falsos positivos paratuberculina”, lo cual sugiere que la prueba de la tuberculina no es la más adecuada para indicar profilaxispara tuberculosis.   doi: http://dx.doi.org/10.7705/biomedica.v33i2.694

PRUEBAS DE IDENTIDAD Y PATERNIDAD EN GANADO BRAHMAN REGISTRADO DE COSTA RICA

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Jorge Campos

2018-01-01

Full Text Available En programas de evaluación genética es indispensable la correcta identificación de los individuos de la población y la certeza de sus relaciones de parentesco. El objetivo de este estudio fue implementar pruebas de identificación y verificación de paternidad mediante 18 marcadores microsatélite en ganado registrado de raza Brahman de Costa Rica. Inicialmente, se calcularon parámetros genéticos poblacionales a partir del análisis de 950 muestras de ADN (7 sementales, 788 vacas y 155 crías colectadas durante los años 2015/2016, procedentes de 13 hatos de ganado registrado. Los promedios de heterocigosidad observada y esperada fueron de 0,67 y 0,70, respectivamente. El índice de fijación fue de 4%, con desviaciones significativas del equilibrio Hardy-Weinberg (EHW en 9 de los 18 loci. Todos los marcadores, excepto ETH225, presentaron contenido de información polimórfica mayor a 0,50. La probabilidad de identidad combinada con todos los marcadores fue 2,4×10-17 para individuos seleccionados aleatoriamente y 2,6×10-7 para hermanos completos. Las probabilidades de exclusión combinada fueron superiores a 0,999. Todos estos parámetros presentaron valores satisfactorios para la realización de pruebas de identidad y paternidad. Seguidamente, se realizaron pruebas de confirmación de paternidad en 137 crías con padre y/o madre reportados procedentes de 3 hatos. Los porcentajes de rechazo de paternidad basados en el principio de exclusión (al menos 2 loci discordantes vs. índices críticos de verosimilitud, fueron respectivamente: 18,2% vs. 24,1% para las madres, 14,0% vs. 12,5% para los padres, y 34,6% vs. 26,3% para los tríos. Se observaron diferencias significativas entre hatos para el porcentaje de rechazo de paternidad, oscilando desde 15,6 a 39,4% en madres, 0 a 30% en padres, y 19,5 a 31,8% en tríos. Se demuestra la necesidad de un mayor control en los apareamientos y en el registro de información genealógica en estos

Repeatability of nest morphology in African weaver birds.

Science.gov (United States)

Walsh, Patrick T; Hansell, Mike; Borello, Wendy D; Healy, Susan D

2010-04-23

It is generally assumed that birds build nests according to a genetic 'template', little influenced by learning or memory. One way to confirm the role of genetics in nest building is to assess the repeatability of nest morphology with repeated nest attempts. Solitary weaver birds, which build multiple nests in a single breeding season, are a useful group with which to do this. Here we show that repeatability of nest morphology was low, but significant, in male Southern Masked weaver birds and not significant in the Village weavers. The larger bodied Village weavers built larger nests than did Southern Masked weavers, but body size did not explain variation in Southern Masked weaver nest dimensions. Nests built by the same male in both species got shorter and lighter as more nests were constructed. While these data demonstrate the potential for a genetic component of variation in nest building in solitary weavers, it is also clear that there remains plenty of scope in both of these species for experience to shape nest construction.

Nest Construction by a Ground-nesting Bird Represents a Potential Trade-off Between Egg Crypticity and Thermoregulation

Science.gov (United States)

Predation selects against conspicuous colors in bird eggs and nests, while thermoregulatory constraints select for nest building behavior that regulates incubation temperatures. We present results that reveal a trade-off between nest crypticity and thermoregulation of eggs base...

Rendimiento en pruebas cognitivas breves, de adultos mayores con demencia en estadios avanzados, residentes de una comunidad urbana de Lima, Perú

Directory of Open Access Journals (Sweden)

Nilton Custodio

Full Text Available Objetivos. Evaluar el rendimiento de la prueba de dibujo de reloj en versión de Manos (PDR-M y Mini Mental State Examination (MMSE en su versión peruana, para detectar demencia de cualquier tipo en adultos mayores residentes de una comunidad urbana de Lima, Perú. Materiales y métodos. Análisis secundario de base de datos, de tipo observacional, analítico y transversal; con diseño de prueba diagnóstica, teniendo como prueba estándar a las evaluaciones clínica y neuropsicológica en conjunto. Se evaluó el rendimiento de las pruebas individualmente, así como de forma combinada. Resultados. El rendimiento de MMSE para la evaluación de pacientes con demencia de cualquier tipo presentó sensibilidad de 64,1%, especificidad de 84,1%, VPP de 24,4%, VPN de 96,7%, LR (+ de 4,03 y LR (- de 0,43. La PDR-M presentó sensibilidad de 89,3%, especificidad de 98,1%, VPP de 79,3%, VPN de 99,1%, LR (+ de 47,79 y LR (- de 0,11. Cuando se aplicaron ambas pruebas, y al menos una de ellas fue positiva, presentaron sensibilidad de 98,1%, especificidad de 84,1%, VPP de 33,1%, VPN de 99,8%, LR (+ de 6,17 y LR (- de 0,02. Al realizar el análisis, por separado, de demencia tipo alzhéimer y no alzhéimer, los valores de los parámetros no se diferencian sustancialmente de los obtenidos para demencias de cualquier tipo. Conclusiones. La combinación de MMSE y PDR-M demuestran un buen rendimiento para detectar demencia en estadios moderado y severo en población residente de una comunidad urbana de Lima.

Prueba de evaluación de la expresión oral: EXPRESA 2004

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José Luis RODRÍGUEZ DIÉGUEZ

2009-11-01

Full Text Available RESUMEN: La investigación a la que se refiere este artículo fue financiada por el Ministerio de Educación, Cultura y Deporte, a través del antiguo Instituto Nacional de Calidad y Evaluación en el año 2002, y tuvo como objetivo la realización de una prueba para la evaluación externa y objetiva de la expresión oral en Educación Primaria. Las actividades que componen su elaboración son las siguientes: creación de una prueba piloto, fijación de los criterios de corrección, aplicación de métodos de lingüística computacional, análisis de datos, análisis de resultados, incluyendo transformaciones posibles para el trabajo, estudio de validez y fiabilidad de la prueba y elaboración de la prueba final.ABSTRACT: The aim of this research team from the University of Salamanca was to design a standardized objective assessment test of spoken Spanish for use in Primary Education as commissioned by what used to be known as the Instituto Nacional de Calidad y Evaluación (INCE at the Ministry of Education. It was decided to opt for the continuous text format as it could include elements of description, narrative and presentation and would allow greater natural expression. We considered using a variant of the visual stimulus from the language assessment test designed by Myklebust (1965. Together with the above-mentioned variables, as well as a series of others selected in a similar fashion, we worked on our prediction of the students' oral achievement. We used some transformations of the variables, to form a normal distribution curve according to the number of words.RÉSUMÉ: La recherche à laquelle cet article se rapporte a été financée par le Ministère d'Éducation, Culture et Sports, à travers l'ancient Institut National de Qualité et d'Évaluation en 2002 et elle a eu comme but la réalisation d'une épreuve pour l'évaluation extérieure et objetive de l'expression orale dans l'Éducation Élémentaire. Les activités qui composent

Sensitivity of Coastal Environments and Wildlife to Spilled Oil: New Hampshire: NESTS (Nest Points)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for nesting birds in New Hampshire. Vector points in this data set represent locations of nesting osprey...

Correlaciones existentes entre una prueba psicométrica (WISC) y una prueba contextual que permite valorar el tipo de inteligencia que poseen los niños y las niñas con bajos puntajes en coeficiente intelectual y que se encuentran matriculados en instituciones educativas oficiales del municipio de Pereira

OpenAIRE

Henao García, Luz Stella; López Galindo, Dora Elsy; Suárez Castro, María Ofelia

2004-01-01

Tesis (Maestría en Educación y Desarrollo Humano). Universidad de Manizales. Facultad de Ciencias Sociales y Humanas. CINDE, 2004 Correlaciones existentes entre una prueba psicométrica (WISC) y una prueba contextual que permite valorar el tipo de inteligencia que poseen los niños y las niñas con bajos puntajes en coeficiente intelectual y que se encuentran matriculados en instituciones educativas oficiales del municipio de Pereira

Evaluación de una prueba rápida para el diagnostico de Malaria en áreas endémicas del Perú

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Nancy Arrospide V

2006-04-01

Full Text Available Objetivos: Evaluar la sensibilidad, especificidad y valores predictivos de la prueba rapida basada en la deteccion de la pLDH (OptiMALR kit individual para el diagnostico de malaria en areas endemicas del Peru. Materiales y metodos: Estudio transversal realizado con pacientes febriles atendidos en centros de salud de la selva norte del Peru (San Martin y Loreto, de abril a diciembre de 2001. A cada paciente se le realizo la gota gruesa, la prueba OptiMALR y densidad parasitaria en forma ciega, por personal local capacitado y luego en el Laboratorio Nacional de Referencia de Malaria. Se calculo la sensibilidad (S, especificidad (E, valor predictivo positivo (VPP y valor predictivo negativo(VPN de la prueba OptiMALR en relacion a la gota gruesa para el diagnostico de malaria global y segun especie (P.falciparum y P.vivax. Resultados: Se incluyeron 346 muestras, 170 positivas. La prueba OptiMALR tuvo niveles de S=95,7%, E=97,1%, VPP=97,7%, VPN=95,3% independientemente de la especie. Para P.falciparum tuvo S=90,5%, E=97,3%, VPP=67,9 y VPN=99.4%; en tanto que para P.vivax S=92,0%, E=99,0%, VPP=98,7% y VPN=93,5%. Las sensibilidades estratificadas por parasitemia fueron 97,0% (5000 parasitos/¥ìL, 99% (100-5000 p/¥ìL y 50% (<100p/¥ìL. Conclusiones: La prueba rapida OptiMALR es un metodo con buena sensibilidad y especificidad para el diagnostico de malaria y puede ser usado en lugares donde no se dispone de laboratorios o microscopistas.

Nest trampling and ground nesting birds: Quantifying temporal and spatial overlap between cattle activity and breeding redshank.

Science.gov (United States)

Sharps, Elwyn; Smart, Jennifer; Mason, Lucy R; Jones, Kate; Skov, Martin W; Garbutt, Angus; Hiddink, Jan G

2017-08-01

Conservation grazing for breeding birds needs to balance the positive effects on vegetation structure and negative effects of nest trampling. In the UK, populations of Common redshank Tringa totanus breeding on saltmarshes declined by >50% between 1985 and 2011. These declines have been linked to changes in grazing management. The highest breeding densities of redshank on saltmarshes are found in lightly grazed areas. Conservation initiatives have encouraged low-intensity grazing at nest trampling. If livestock distribution is not spatially or temporally homogenous but concentrated where and when redshank breed, rates of nest trampling may be much higher than expected based on livestock density alone. By GPS tracking cattle on saltmarshes and monitoring trampling of dummy nests, this study quantified (i) the spatial and temporal distribution of cattle in relation to the distribution of redshank nesting habitats and (ii) trampling rates of dummy nests. The distribution of livestock was highly variable depending on both time in the season and the saltmarsh under study, with cattle using between 3% and 42% of the saltmarsh extent and spending most their time on higher elevation habitat within 500 m of the sea wall, but moving further onto the saltmarsh as the season progressed. Breeding redshank also nest on these higher elevation zones, and this breeding coincides with the early period of grazing. Probability of nest trampling was correlated to livestock density and was up to six times higher in the areas where redshank breed. This overlap in both space and time of the habitat use of cattle and redshank means that the trampling probability of a nest can be much higher than would be expected based on standard measures of cattle density. Synthesis and applications : Because saltmarsh grazing is required to maintain a favorable vegetation structure for redshank breeding, grazing management should aim to keep livestock away from redshank nesting habitat between mid

The design and function of birds' nests

Science.gov (United States)

Mainwaring, Mark C; Hartley, Ian R; Lambrechts, Marcel M; Deeming, D Charles

2014-01-01

All birds construct nests in which to lay eggs and/or raise offspring. Traditionally, it was thought that natural selection and the requirement to minimize the risk of predation determined the design of completed nests. However, it is becoming increasingly apparent that sexual selection also influences nest design. This is an important development as while species such as bowerbirds build structures that are extended phenotypic signals whose sole purpose is to attract a mate, nests contain eggs and/or offspring, thereby suggesting a direct trade-off between the conflicting requirements of natural and sexual selection. Nest design also varies adaptively in order to both minimize the detrimental effects of parasites and to create a suitable microclimate for parents and developing offspring in relation to predictable variation in environmental conditions. Our understanding of the design and function of birds' nests has increased considerably in recent years, and the evidence suggests that nests have four nonmutually exclusive functions. Consequently, we conclude that the design of birds' nests is far more sophisticated than previously realized and that nests are multifunctional structures that have important fitness consequences for the builder/s. PMID:25505520

The design and function of birds' nests.

Science.gov (United States)

Mainwaring, Mark C; Hartley, Ian R; Lambrechts, Marcel M; Deeming, D Charles

2014-10-01

All birds construct nests in which to lay eggs and/or raise offspring. Traditionally, it was thought that natural selection and the requirement to minimize the risk of predation determined the design of completed nests. However, it is becoming increasingly apparent that sexual selection also influences nest design. This is an important development as while species such as bowerbirds build structures that are extended phenotypic signals whose sole purpose is to attract a mate, nests contain eggs and/or offspring, thereby suggesting a direct trade-off between the conflicting requirements of natural and sexual selection. Nest design also varies adaptively in order to both minimize the detrimental effects of parasites and to create a suitable microclimate for parents and developing offspring in relation to predictable variation in environmental conditions. Our understanding of the design and function of birds' nests has increased considerably in recent years, and the evidence suggests that nests have four nonmutually exclusive functions. Consequently, we conclude that the design of birds' nests is far more sophisticated than previously realized and that nests are multifunctional structures that have important fitness consequences for the builder/s.

PROPUESTA DE PROTOCOLO PARA LA CONDUCCIÓN DE LA PRUEBA PRECONSTITUIDA EN VÍCTIMAS ESPECIALMENTE VULNERABLES

Directory of Open Access Journals (Sweden)

José Luis González

2013-09-01

Full Text Available La prueba preconstituida es una fórmula jurídica que en los casos de víctimas especialmente vulnerables tiene dos objetivos fundamentales: por un lado, proteger el testimonio de la víctima (indicio cognitivo del deterioro derivado de múltiples e inadecuados abordajes, y por otro, evitar la revictimización provocada por el sistema policial y de justicia. Conscientes de la ayuda que la Psicología Jurídica puede realizar al desarrollo de esta diligencia procesal, en el presente artículo se desarrolla una propuesta para la conducción de la prueba preconstituida basada en los conocimientos provenientes de la Psicología del Testimonio y de la Psicología de la Victimización Criminal además de la experiencia práctica de psicólogos criminalistas y forenses.

Estimating raptor nesting success: old and new approaches

Science.gov (United States)

Brown, Jessi L.; Steenhof, Karen; Kochert, Michael N.; Bond, Laura

2013-01-01

Studies of nesting success can be valuable in assessing the status of raptor populations, but differing monitoring protocols can present unique challenges when comparing populations of different species across time or geographic areas. We used large datasets from long-term studies of 3 raptor species to compare estimates of apparent nest success (ANS, the ratio of successful to total number of nesting attempts), Mayfield nesting success, and the logistic-exposure model of nest survival. Golden eagles (Aquila chrysaetos), prairie falcons (Falco mexicanus), and American kestrels (F. sparverius) differ in their breeding biology and the methods often used to monitor their reproduction. Mayfield and logistic-exposure models generated similar estimates of nesting success with similar levels of precision. Apparent nest success overestimated nesting success and was particularly sensitive to inclusion of nesting attempts discovered late in the nesting season. Thus, the ANS estimator is inappropriate when exact point estimates are required, especially when most raptor pairs cannot be located before or soon after laying eggs. However, ANS may be sufficient to assess long-term trends of species in which nesting attempts are highly detectable.

Response of beach-nesting American Oystercatchers to off-road vehicles: An experimental approach reveals physiological nuances and decreased nest attendance

Science.gov (United States)

Felton, Shilo K.; Pollock, Kenneth H.; Simons, Theodore R.

2018-01-01

Shorebird populations face increasing challenges as rising sea levels and growing human populations constrain their breeding habitats. On recreational beaches, the nesting season often coincides with a season of high visitor use, increasing the potential for conflict, which may negatively influence beach-nesting shorebird species. We designed a field experiment to study the responses of nesting American Oystercatchers (Haematopus palliatus) to off-road passenger vehicles (ORVs) at Cape Hatteras and Cape Lookout National Seashores in North Carolina, USA. We used continuous video and heart rate recordings to assess changes in the behavior and physiology of incubating oystercatchers. We conducted driving experiments affecting 7 nesting pairs in 2014 and 19 nesting pairs in 2015, between April and July of each year. Experimental treatments were repeated throughout the incubation period for each nest. Although responses were highly variable within and among pairs, paired randomized permutation tests indicated that, overall, oystercatcher pairs spent a greater proportion of time with their heads up and exhibited slower heart rates during driving treatments. Pairs also left their nests more frequently and attended their nests for a lower proportion of time during driving treatments, although these responses diminished over time. Higher nest attendance and lower departure rates late in incubation may have reflected a stronger attachment to nests closer to hatching or habituation to the driving treatment, although individuals continued to exhibit physiological responses to passing vehicles throughout incubation. Beach-nesting birds may benefit from reduced vehicle traffic at their nesting sites, allowing parents to spend more time attending the nest and less time on defensive behaviors.

EFL Students' and Teachers' Attitudes toward Foreign Language Speaking Anxiety: A Look at NESTs and Non-NESTs

Science.gov (United States)

Han, Turgay; Tanriöver, Ahmet Serkan; Sahan, Özgür

2016-01-01

Native English Speaking Teachers (NESTs) have been employed in various English language teaching (ELT) positions and departments at private and state universities in Turkey, particularly over the last three decades. However, undergraduate EFL students' attitudes toward NESTs and Non-Native English Speaking Teachers (Non-NESTs) remain seriously…

Copper accumulation by stickleback nests containing spiggin.

Science.gov (United States)

Pinho, G L L; Martins, C M G; Barber, I

2016-07-01

The three-spined stickleback is a ubiquitous fish of marine, brackish and freshwater ecosystems across the Northern hemisphere that presents intermediate sensitivity to copper. Male sticklebacks display a range of elaborate reproductive behaviours that include nest construction. To build the nests, each male binds nesting material together using an endogenous glycoprotein nesting glue, known as 'spiggin'. Spiggin is a cysteine-rich protein and, therefore, potentially binds heavy metals present in the environment. The aim of this study was to investigate the capacity of stickleback nests to accumulate copper from environmental sources. Newly built nests, constructed by male fish from polyester threads in laboratory aquaria, were immersed in copper solutions ranging in concentration from 21.1-626.6 μg Cu L(-1). Bundles of polyester threads from aquaria without male fish were also immersed in the same copper solutions. After immersion, nests presented higher amounts of copper than the thread bundles, indicating a higher capacity of nests to bind this metal. A significant, positive correlation between the concentration of copper in the exposure solution and in the exposed nests was identified, but there was no such relationship for thread bundles. Since both spiggin synthesis and male courtship behaviour are under the control of circulating androgens, we predicted that males with high courtship scores would produce and secrete high levels of the spiggin protein. In the present study, nests built by high courtship score males accumulated more copper than those built by low courtship score males. Considering the potential of spiggin to bind metals, the positive relationship between fish courtship and spiggin secretion seems to explain the higher amount of copper on the nests from the fish showing high behaviour scores. Further work is now needed to determine the consequences of the copper binding potential of spiggin in stickleback nests for the health and survival of

El sistema educativo de Finlandia y su ??xito en la prueba PISA

OpenAIRE

Gripenberg, Martin; Lizarte Sim??n, Emilio Jes??s

2012-01-01

Las pruebas PISA muestran una vez m??s el buen resultado referido al rendimiento escolar en Finlandia. Entre sus variadas estructuras organizativas y directivas puede discurrirse la existencia de un consenso sobre la pol??tica educativa com??n que refleja las directrices a considerar en el desarrollo del curr??culo. Los municipios tienen una gran relevancia a la hora de organizar y concretar la educaci??n b??sica adem??s de definir las intenciones en el curr??culo. Los centros y l...

Construction patterns of birds' nests provide insight into nest-building behaviours

OpenAIRE

Biddle, Lucia; Goodman, Adrian; Deeming, Charles

2017-01-01

Previous studies have suggested that birds and mammals select materials needed for nest building based on their thermal or structural properties, although the amounts or properties of the materials used have been recorded for only a very small number of species. Some of the behaviours underlying the construction of nests can be indirectly determined by careful deconstruction of the structure and measurement of the biomechanical properties of the materials used. Here we examined this idea in a...

Constructing bald eagle nests with natural materials

Science.gov (United States)

T. G. Grubb

1995-01-01

A technique for using natural materials to build artificial nests for bald eagles (Haliaeetus leucocephalus) and other raptors is detailed. Properly constructed nests are as permanently secured to the nest tree or cliff substrate as any eagle-built nest or human-made platform. Construction normally requires about three hours and at least two people. This technique is...

Light pollution affects nesting behavior of loggerhead turtles and predation risk of nests and hatchlings.

Science.gov (United States)

Silva, Elton; Marco, Adolfo; da Graça, Jesemine; Pérez, Héctor; Abella, Elena; Patino-Martinez, Juan; Martins, Samir; Almeida, Corrine

2017-08-01

The introduction of artificial light into wildlife habitats is a rapidly expanding aspect of global change, which has many negative impacts on a wide range of taxa. In this experimental study, which took place on a beach located on the island of Boa Vista (Cabo Verde), three types of artificial light were tested on nesting loggerhead sea turtles as well as on ghost crabs, which intensively predate on nests and hatchlings, to determine the effects they would produce on the behavior of both species. Over the course of 36days, female loggerheads and ghost crabs were studied under yellow, orange and red lights, with observations also being made on dark nights that served as a control treatment. During this period, the frequencies of nesting attempts, the time taken by turtles to complete each phase of the nesting process, and ghost crab abundance and behaviors were carefully recorded. 1146 loggerhead nesting attempts were observed and recorded during the experiments, and results showed a decrease in nesting attempts of at least 20% when artificial lighting was present. A significant decline in successful attempts was also observed within the central sections of the beach, which corresponded to those that received more light. This artificial lighting significantly increased the time that turtles spent on the nesting process and forced them to do more extensive beach crawls. Despite this, the presence of light had no apparent effect on the final selection of the nesting site. Yellow and orange lights significantly disrupted the sea finding behavior and turtles were often unable to orient themselves seaward under these color lights. Disoriented turtles were observed crawling in circuitous paths in front of the light source for several minutes. In addition, artificial lights had the potential to increase the number of ghost crabs present within the illuminated stretches of the beach. However, only yellow lighting produced a significant change on aggressive and prey

Estudio bibliométrico de publicaciones científicas que utilizan pruebas de reconocimiento de emociones faciales

Directory of Open Access Journals (Sweden)

Graciela Jeanneret

2015-01-01

Full Text Available El trabajo se enmarca dentro de la perspectiva evolucionista, la cual sostiene la existencia de emociones universales, enfatizando el estudio de su expresión facial y su reconocimiento. Si bien la creación del sistema FACS en 1978 por Ekman impulsó la construcción de instrumentos de evaluación del reconocimiento de emociones faciales, actualmente no existen pruebas locales que midan dicha habilidad. El objetivo de este estudio fue la realización de un análisis bibliométrico de investigaciones científicas publicadas entre 1976 y agosto de 2011 que utilizan pruebas de reconocimiento de emociones faciales. Este proceso de sistematización de los documentos brinda visibilidad sobre el estado actual de la ciencia en relación a dichas pruebas. Se analizaron los indicadores de productividad, colaboración, índice h y análisis de materia. Éstos evidenciaron un crecimiento sistemático cada vez más pronunciado en la utilización de investigaciones en el reconocimiento de emociones faciales. Estas utilizan fotografías tales como el POFA y el JACFEE en población adulta de ambos sexos, adquiriendo relevancia el estudio de patologías, principalmente la esquizofrenia. Estos resultados, a su vez, podrán utilizarse como fundamento para posteriores proyectos de investigación que aporten al progreso de la ciencia.

Bristol Bay, Alaska Subarea ESI: NESTS (Nest Points)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for nesting seabirds (alcids, pelagic birds), gulls, terns, diving birds, and raptors in the Bristol Bay...

Strong selection on mandible and nest features in a carpenter bee that nests in two sympatric host plants.

Science.gov (United States)

Flores-Prado, Luis; Pinto, Carlos F; Rojas, Alejandra; Fontúrbel, Francisco E

2014-05-01

Host plants are used by herbivorous insects as feeding or nesting resources. In wood-boring insects, host plants features may impose selective forces leading to phenotypic differentiation on traits related to nest construction. Carpenter bees build their nests in dead stems or dry twigs of shrubs and trees; thus, mandibles are essential for the nesting process, and the nest is required for egg laying and offspring survival. We explored the shape and intensity of natural selection on phenotypic variation on three size measures of the bees (intertegular width, wing length, and mandible area) and two nest architecture measures (tunnel length and diameter) on bees using the native species Chusquea quila (Poaceae), and the alloctonous species Rubus ulmifolius (Rosaceae), in central Chile. Our results showed significant and positive linear selection gradients for tunnel length on both hosts, indicating that bees building long nests have more offspring. Bees with broader mandibles show greater fitness on C. quila but not on R. ulmifolius. Considering that C. quila represents a selective force on mandible area, we hypothesized a high adaptive value of this trait, resulting in higher fitness values when nesting on this host, despite its wood is denser and hence more difficult to be bored.

Preference of rabbit does among different nest materials

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T.P. Farkas

2018-03-01

Full Text Available Nest quality is important for the survival of new-born rabbits. Nesting material in rabbit farms generally consists of wood shavings, which is completely different from the dry grass used by the European wild rabbit (Oryctolagus cuniculus. The aim of the experiments was to examine which nest materials are preferred by rabbit does when building their nest. In experiment 1, the choice of multiparous rabbit does (n=37 among nest boxes bedded with different nesting materials was monitored. In each pen (1.0×1.83 m 1 doe and 4 nest boxes (0.37×0.23×0.31 m with different nest materials (meadow hay [H], wheat straw [S], fine fibre material [Lignocel®, L] or wood shavings [W] were placed 3 days before the expected parturition (gestation length is about 31 d in the Pannon White breed. Some 48.6% of the does kindled in nest boxes that contained pure materials (L: 40.5%, S: 5.4%, H: 2.7%, and 51.3% of the does kindled in nest boxes where the nest materials of different nest boxes were mixed by the does (S with L: 21.5%, S with L and H: 5.4%, W with L: 8.1%, L with H and S: 5.4%. Does preferred kindling in the nest box bedded with L, and most of them refused the nest box with W. In experiment 2/a (n=32 does and 2/b (n=25 does, each pen (1×0.91 m was equipped with 3 and 2 hay racks and filled with H, S or L, and H or S, respectively. The experiments lasted from the 27th day of pregnancy until the day of parturition and 24-h video recordings (10 does/experiment were evaluated throughout the experiment. The events of carrying the nest materials from the hay racks were registered. In experiment 2/a, the frequency of nest material carrying was highest on the day of parturition. The preferred nest material was L (compared to H and S on each experimental day except day 30 of pregnancy. At the day of kindling, 87.5, 6.3 and 6.3% of the nests contained pure L, mixed L-H and L-S, respectively. In experiment 2/b, the frequency of nest material carrying (mostly S

Is it safe to nest near conspicuous neighbours? Spatial patterns in predation risk associated with the density of American Golden-Plover nests.

Science.gov (United States)

Giroux, Marie-Andrée; Trottier-Paquet, Myriam; Bêty, Joël; Lamarre, Vincent; Lecomte, Nicolas

2016-01-01

Predation is one of the main factors explaining nesting mortality in most bird species. Birds can avoid nest predation or reduce predation pressure by breeding at higher latitude, showing anti-predator behaviour, selecting nest sites protected from predators, and nesting in association with protective species. American Golden-Plovers (Pluvialis dominica) defend their territory by using various warning and distraction behaviours displayed at varying levels of intensity (hereafter "conspicuous behaviour"), as well as more aggressive behaviours such as aerial attacks, but only in some populations. Such antipredator behaviour has the potential to repel predators and thus benefit the neighbouring nests by decreasing their predation risk. Yet, conspicuous behaviour could also attract predators by signalling the presence of a nest. To test for the existence of a protective effect associated with the conspicuous antipredator behaviour of American Golden-Plovers, we studied the influence of proximity to plover nests on predation risk of artificial nests on Igloolik Island (Nunavut, Canada) in July 2014. We predicted that the predation risk of artificial nests would decrease with proximity to and density of plover nests. We monitored 18 plover nests and set 35 artificial nests at 30, 50, 100, 200, and 500 m from seven of those plover nests. We found that the predation risk of artificial nests increases with the density of active plover nests. We also found a significant negative effect of the distance to the nearest active protector nest on predation risk of artificial nests. Understanding how the composition and structure of shorebird communities generate spatial patterns in predation risks represents a key step to better understand the importance of these species of conservation concern in tundra food webs.

Low heritability of nest construction in a wild bird.

Science.gov (United States)

Järvinen, Pauliina; Kluen, Edward; Brommer, Jon E

2017-10-01

In birds and other taxa, nest construction varies considerably between and within populations. Such variation is hypothesized to have an adaptive (i.e. genetic) basis, but estimates of heritability in nest construction are largely lacking. Here, we demonstrate with data collected over 10 years from 1010 nests built by blue tits in nest-boxes that nest size (height of nest material) and nest composition (proportion of feathers in the nest) are repeatable but only weakly (12-13%) heritable female traits. These findings imply that nest construction may evolve but only if subjected to strong and consistent selection pressures. © 2017 The Author(s).

ANÁLISIS DE PRUEBAS DE PRESIÓN EN YACIMIENTOS NATURALMENTE FRACTURADOS Y SENSIBLES A ESFUERZOS

Directory of Open Access Journals (Sweden)

MARIA ADELAIDA ARANGO ACEVEDO

2009-01-01

Full Text Available La caracterización de los yacimientos se realiza mediante diferentes técnicas como interpretación de registros, análisis de núcleos, sismicidad, interpretación de pruebas de pozo, entre otras. Las pruebas de presión constituyen una herramienta clave para la obtención de los parámetros característicos de los yacimientos de hidrocarburos. En las últimas décadas se han realizado estudios que consideran el cambio en las propiedades de la roca como respuesta a los cambios de presión que siente el yacimiento por las diversas actividades de producción. Teniendo esto en mente se desarrolla un software que permite la interpretación de transientes y que puede ser usado para diferentes escenarios. El planteamiento del problema presenta la ecuación de flujo monofásico de gas o petróleo para yacimientos naturalmente fracturados y considera la sensibilidad con el módulo de permeabilidad. La solución serealiza con el algoritmo de Stehfest, utilizado ampliamente en la industria petrolera.

EXCELENCIA Y EQUIDAD EN PRUEBAS DE ADMISIÓN: UNA PROPUESTA EMERGENTE PARA LA UNIVERSIDAD DE COSTA RICA

Directory of Open Access Journals (Sweden)

Montero Rojas Eiliana

2010-08-01

Full Text Available Resumen:Se desarrolla una propuesta referente a la equidad en la admisión a la Universidad de Costa Rica (UCR y respaldada por algunas evidencias empíricas iniciales. De acuerdo con el modelo establecido por esta casa de estudios, el propósito de las pruebas de admisión a la Universidad es medir el potencial intelectual para el aprendizaje y no lo que el examinado ya sabe. En este contexto, los conceptos de inteligencia fluida e inteligencia cristalizada de Raymond Cattell parecen ser un apropiado marco de referencia para brindar una respuesta científica a esta problemática. La inteligencia fluida se refiere a habilidades que dependen menos de las oportunidades educativas previas y de la cultura, comparada con la inteligencia cristalizada. Se está construyendo y validando una prueba para medir este constructo. Se espera que esta prueba ayude a identificar de manera más precisa estudiantes que poseen potencial académico pero que provienen de ambientes con menores oportunidades educativas. Algunas evidencias empíricas que apoyan esta propuesta se derivan de una primera aplicación piloto de una versión inicial de dicho test en una muestra de 321 estudiantes de la UCR, conjuntamente con la prueba de “Factor g de Cattell”, una conocida prueba de inteligencia fluida. El estudio buscaba obtener evidencia de la validez concurrente entre las dos pruebas y generar estimaciones de tiempo, dificultad y confiabilidad para el test construido en la UCR. Los resultados generados por esta autora indicaron niveles aceptables (aunque no óptimos de validez concurrente y confiabilidad. El efecto de velocidad probablemente esté provocando una subestimación de la confiabilidad, por lo que se recomienda, para el futuro, un diseño de test-retest.Abstract:A proposal around the topic of equity in admission to the University of Costa Rica is presented and some initial evidences supporting it are provided. According to the admission model established by

Is it safe to nest near conspicuous neighbours? Spatial patterns in predation risk associated with the density of American Golden-Plover nests

Directory of Open Access Journals (Sweden)

Marie-Andrée Giroux

2016-08-01

Full Text Available Predation is one of the main factors explaining nesting mortality in most bird species. Birds can avoid nest predation or reduce predation pressure by breeding at higher latitude, showing anti-predator behaviour, selecting nest sites protected from predators, and nesting in association with protective species. American Golden-Plovers (Pluvialis dominica defend their territory by using various warning and distraction behaviours displayed at varying levels of intensity (hereafter “conspicuous behaviour”, as well as more aggressive behaviours such as aerial attacks, but only in some populations. Such antipredator behaviour has the potential to repel predators and thus benefit the neighbouring nests by decreasing their predation risk. Yet, conspicuous behaviour could also attract predators by signalling the presence of a nest. To test for the existence of a protective effect associated with the conspicuous antipredator behaviour of American Golden-Plovers, we studied the influence of proximity to plover nests on predation risk of artificial nests on Igloolik Island (Nunavut, Canada in July 2014. We predicted that the predation risk of artificial nests would decrease with proximity to and density of plover nests. We monitored 18 plover nests and set 35 artificial nests at 30, 50, 100, 200, and 500 m from seven of those plover nests. We found that the predation risk of artificial nests increases with the density of active plover nests. We also found a significant negative effect of the distance to the nearest active protector nest on predation risk of artificial nests. Understanding how the composition and structure of shorebird communities generate spatial patterns in predation risks represents a key step to better understand the importance of these species of conservation concern in tundra food webs.

Hierarchically nested river landform sequences

Science.gov (United States)

Pasternack, G. B.; Weber, M. D.; Brown, R. A.; Baig, D.

2017-12-01

River corridors exhibit landforms nested within landforms repeatedly down spatial scales. In this study we developed, tested, and implemented a new way to create river classifications by mapping domains of fluvial processes with respect to the hierarchical organization of topographic complexity that drives fluvial dynamism. We tested this approach on flow convergence routing, a morphodynamic mechanism with different states depending on the structure of nondimensional topographic variability. Five nondimensional landform types with unique functionality (nozzle, wide bar, normal channel, constricted pool, and oversized) represent this process at any flow. When this typology is nested at base flow, bankfull, and floodprone scales it creates a system with up to 125 functional types. This shows how a single mechanism produces complex dynamism via nesting. Given the classification, we answered nine specific scientific questions to investigate the abundance, sequencing, and hierarchical nesting of these new landform types using a 35-km gravel/cobble river segment of the Yuba River in California. The nested structure of flow convergence routing landforms found in this study revealed that bankfull landforms are nested within specific floodprone valley landform types, and these types control bankfull morphodynamics during moderate to large floods. As a result, this study calls into question the prevailing theory that the bankfull channel of a gravel/cobble river is controlled by in-channel, bankfull, and/or small flood flows. Such flows are too small to initiate widespread sediment transport in a gravel/cobble river with topographic complexity.

Gestión de conocimiento: la solución para disminuir el reproceso en las pruebas de software

Directory of Open Access Journals (Sweden)

Luz A. Perona Ossaba

2012-12-01

Full Text Available La gestión de conocimiento se ha convertido en una clave fundamental en los procesos de la ingeniería de software, permitiendo mejorar y optimizar cada una de las actividades que se ejecutan durante todo el ciclo de desarrollo de software. Cada una de las etapas de la ingeniería de software ha adoptado de la gestión de conocimiento algunas características, de acuerdo con las necesidades que se presentan, adecuándolos y fortaleciéndolos para reducir los tiempos y disminuir la fuga de información dentro de las organizaciones. Es por esto que las pruebas de software han adoptado la gestión de conocimiento como la alternativa para disminuir el reproceso en las pruebas de software.

Common cuckoos Cuculus canorus change their nest-searching strategy according to the number of available host nests

Czech Academy of Sciences Publication Activity Database

Jelínek, Václav; Procházka, Petr; Požgayová, Milica; Honza, Marcel

2014-01-01

Roč. 156, č. 1 (2014), s. 189-197 ISSN 0019-1019 R&D Projects: GA AV ČR IAA600930605; GA AV ČR IAA600930903 Institutional support: RVO:68081766 Keywords : brood parasitism * cuckoo perch * edge effect host aggression * host choice * nest height * nest visibility * nest volume Subject RIV: EG - Zoology Impact factor: 1.921, year: 2014

An economical wireless cavity-nest viewer

Science.gov (United States)

Daniel P. Huebner; Sarah R. Hurteau

2007-01-01

Inspection of cavity nests and nest boxes is often required during studies of cavity-nesting birds, and fiberscopes and pole-mounted video cameras are sometimes used for such inspection. However, the cost of these systems may be prohibitive for some potential users. We describe a user-built, wireless cavity viewer that can be used to access cavities as high as 15 m and...

Nesting Biology and Occurrence of Social Nests in a Bivoltine and Basically Solitary Halictine Bee, Lasioglossum (Lasioglossum) scitulum Smith (Hymenoptera : Halictidae)

OpenAIRE

Ryoichi, MIYANAGA; Yasuo, MAETA; Kazuo, HOSHIKAWA; Division of Environmental Biology, Faculty of Life and Environmental Science, Shimane University; Division of Environmental Biology, Faculty of Life and Environmental Science, Shimane University; Division of Environmental Biology, Faculty of Life and Environmental Science, Shimane University

2000-01-01

The life cycle and sociality of the halictine bee, Lasioglossum (Lasioglossum) scitulum were studied in a greenhouse at Matsue (lat. 35°22′N), south-western Japan in 1988 and 1989. This species was a bivoltine bee with solitary to primitively social behavior. During the summer brooding period of 1988, 51 solitary nests and 8 multi-female nests (3 matrifilial and 5 sororal nests) were discovered. In 1989, 11 multi-female nests (3 matrifilial and 8 sororal nests), together with 59 solitary nest...

¿La prueba del frío podría predecir la aparición de eventos cardiovasculares en pacientes sin enfermedad coronaria demostrada?

Directory of Open Access Journals (Sweden)

Jorge Lerman

2010-01-01

Full Text Available La disfunción endotelial es la primera alteración conocida que interviene en el desarrollo de la cardiopatía isquémica. La falta de metodologías adecuadamente desarrolladas que permitan reconocer en la etapa preclínica de la enfermedad a los pacientes en riesgo de padecer un evento cardiovascular alertan sobre la necesidad de adoptar métodos adicionales de diagnóstico para su identificación precoz. La función endotelial en las arterias coronarias fue evaluada con perfusión miocárdica SPECT y la prueba del frío.ObjetivosDeterminar la prevalencia de la prueba del frío en 511 pacientes sin cardiopatía isquémica demostrada, como también de los factores de riesgo coronario asociados en aquellos con resultado positivo y analizar la incidencia de eventos cardiovasculares en un seguimiento de cincuenta meses.Material y métodosEn un servicio de medicina nuclear se realizó en 511 pacientes un estudio tomográfico de perfusión miocárdica (SPECT, cuyo resultado ante el ejercicio reveló una captación uniforme del radiotrazador. Ningún paciente tenía antecedentes de revascularización miocárdica ni de infarto previo. Entre los dos y los cinco días posteriores al ingreso en el protocolo se efectuó la prueba del frío. Se considera que ésta es positiva cuando se observa hipocaptación del radioisótopo en algún segmento que no existía en el estudio del esfuerzo y negativo cuando no hay cambios en la captación entre ambos estudios.El seguimiento promedio fue de 24 ± 13 meses, el cual pudo completarse en el 95% de los participantes. Se analizaron los eventos mortalidad cardíaca, infarto de miocardio, accidente cerebrovascular y procedimientos de revascularización.ResultadosLa edad media fue de 58,7 años con una prevalencia del sexo masculino del 52,6%. Prevalencia de factores de riesgo: diabetes 10,3%, dislipidemia 69,3%, hipertensión arterial 63,4%, obesidad 25,2% y tabaquismo 22,3%.En el 32,4% de los pacientes la prueba fue

Reproducibilidad de pruebas serológicas para el diagnóstico de infección por Trypanosoma cruzi en mujeres embarazadas de una zona endémica de Santander, Colombia

Directory of Open Access Journals (Sweden)

Yeny Zulay Castellanos

2014-06-01

Full Text Available Introducción. El diagnóstico de infección por Trypanosoma cruzi en fase crónica se hace por medio de pruebas serológicas cuya reproducibilidad no está muy documentada. Objetivo. Evaluar la reproducibilidad de las pruebas serológicas ELISA, IFI y HAI para el diagnóstico de infección por T. cruzi en mujeres embarazadas de una zona endémica de Santander. Materiales y métodos. Mediante la evaluación de la tecnología diagnóstica se determinó la reproducibilidad de las pruebas serológicas ELISA, IFI y HAI en muestras de suero y elución sanguínea, seleccionadas mediante muestreo de corte transversal y pertenecientes a mujeres embarazadas de una zona endémica para enfermedad de Chagas en Santander. Se usó el software Stata, versión 10.0, para los análisis estadísticos. La prueba con la mejor reproducibilidad se determinó por medio de la comparación de los índices kappa más altos de cada técnica. Resultados. Se evaluaron 777 sueros y elución sanguíneas. En suero, la prueba ELISA (punto de corte=0,3, la IFI (punto de corte=1/32 y la HAI (punto de corte=1/16 presentaron índices kappa mayores de 0,8 (0,98, IC95%: 0,93-1,00; 0,98, IC95%: 0,92-1,00 y 0,88, IC95%: 0,74-0,97, respectivamente; no se observaron diferencias estadísticamente significativas entre las tres pruebas evaluadas (p>0,05. Para la elución sanguínea, el índice kappa estuvo por debajo de 0,8 (valor kappa más alto: 0,55, IC95%: 0,41-0,68. Conclusiones. Las tres pruebas serológicas presentaron reproducibilidad perfecta en suero, determinada mediante el índice kappa, por lo que cualquiera de ellas sería útil para establecer el diagnóstico de infección por T. cruzi. Por su simplicidad y su costo, la prueba ELISA se recomienda como prueba de elección para los programas de tamización de esta infección.

Prueba de susceptibilidad antiparasitaria in vitro para Blastocystis hominis, Entamoeba histolytica-E. dispar, Balantidium coli

Directory of Open Access Journals (Sweden)

Rito Zerpa Larrauri

2012-01-01

Full Text Available Antecedentes: Pruebas de susceptibilidad antiparasitaria in vitro para Blastocystis hominis, Entamoeba histolytica-E. dispar y Balantidium coli, así como el cultivo para protozoarios intestinales, han sido publicados escasamente en la literatura médica. En nuestro medio aún no se ha comunicado pruebas de susceptibilidad in vitro para los parásitos mencionados. Objetivos: Plantear una alternativa de prueba de susceptibilidad antiparasitaria in vitro y conocer su resistencia frente a los antimicrobianos. Diseño: Estudio prospectivo, descriptivo. Instituciones: Instituto de Medicina Tropical "Daniel Alcides Carrión", Universidad Nacional Mayor de San Marcos, e Instituto Especializado de Salud del Niño, Lima, Perú. Material biológico: Cultivos de Blastocystis hominis, Entamoeba histolytica-E. dispar y Balantidium coli frente a cinco antimicrobianos. Métodos: Se trabajó con 64 cultivos de Blastocystis hominis, 16 de Entamoeba histolytica-dispar y 16 de Balantidium coli, frente a cinco antimicrobianos: metronidazol, cotrimoxazol, tetraciclina, furazolidona y ciprofloxacina. Las cepas de B. hominis, E. histolytica-E. dispar fueron cultivadas en el medio de Pavlova modificado, de 500 muestras de heces de niños con diagnóstico de parasitosis intestinal y las de B. coli de heces de cerdo. Las pruebas de susceptibilidad in vitro se realizaron con el método de microcultivos en el medio de Pavlova modificado, en pocitos con 200 uL del medio sin antiparasitarios (control y con antiparasitarios en 10 concentraciones, desde 128 ug/mL hasta 0,25 ug/mL; luego de incubación a 36º C por 48 horas, la lectura por examen microscópico directo comparó el desarrollo en el medio control con el desarrollo en los pocitos conteniendo los antimicrobianos. Principales medidas de resultados: Concentración inhibitoria mínima (CIM. Resultados: Se encontró para B. hominis, con metronidazol CIM 90: 64 ug/mL y CIM 50: 2 ug/mL; para E. histolytica-E. dispar con

Subterranean ant nests: Trace fossils past and future?

OpenAIRE

Tschinkel, Walter R.

2003-01-01

Many species of ants excavate complex, species-typical nests in soil. The basic structural units of many nests are descending tunnels connecting flattened, generally horizontal chambers of oval to lobed outline. The species-typical structure of many nests results from variation in the size, shape, number and arrangement of these basic elements. Nest architecture can be rendered by filling subterranean nests with a thin slurry of orthodontal plaster, then excavating and reconstructing the hard...

Converting nested algebra expressions into flat algebra expressions

NARCIS (Netherlands)

Paredaens, J.; Van Gucht, D.

1992-01-01

Nested relations generalize ordinary flat relations by allowing tuple values to be either atomic or set valued. The nested algebra is a generalization of the flat relational algebra to manipulate nested relations. In this paper we study the expressive power of the nested algebra relative to its

¿Le han hecho pruebas de detección de cáncer colorrectal? - (Have You Been Tested for Colorectal Cancer?)

Centers for Disease Control (CDC) Podcasts

2013-11-05

Este podcast se basa en la edición de noviembre del 2013 del informe Signos Vitales de los CDC. Las pruebas de detección de cáncer colorrectal salvan vidas, pero solo si usted se las hace. Si tiene entre 50 y 75 años, hable con su médico acerca de cuál prueba es mejor para usted. Si tiene enfermedad inflamatoria intestinal o antecedentes de cáncer colorrectal o pólipos en su familia, pregúntele al médico si debería empezar a hacerse las pruebas de detección antes de cumplir los 50 años.  Created: 11/5/2013 by Centers for Disease Control and Prevention (CDC).   Date Released: 11/5/2013.

Evaluación de la prueba rápida inmunocromatográfica Binax NOW® ICT Pf/Pv para el diagnóstico del paludismo en un área endémica de Colombia

Directory of Open Access Journals (Sweden)

Adriana Pabón

2007-06-01

Conclusiones. La prueba Binax NOW® malaria ICT Pf/Pv como prueba diagnóstica mostró una sensibilidad muy baja para infecciones por P. falciparum y su capacidad para detectar parasitemias menores de 500 parásitos/ul es mínima. Como diagnóstico confirmatorio, la prueba ICT P.f/P.v. tiene buena sensibilidad para P. falciparum. Su uso para seguimiento de los pacientes no se recomienda.

Does removal of mammalian predators significantly affect success of simulated nests in linear habitats? Case study on American mink Mustela vison \\& Predation on simulated duck nests in relation to nest density and habitat type

OpenAIRE

PADYŠÁKOVÁ, Eliška

2007-01-01

This thesis is made up of two studies dealing with predation of waterfowl nests. in the first study, we determined wheather removal of introduced predator Mustela vison affected nest survival of simulated duck nests in linear habitat. In the second study, we tested two hypothesis: 1)predation depends on density of waterfowl nests, 2)mammals are main predators in forest habitat and birds mainly depredate nests deployed in open land.

Biology of a trap-nesting wasp of one species the ground-nesting Liris (Hymenoptera: Crabronidae from the Atlantic Forest of southern Brazil

Directory of Open Access Journals (Sweden)

Camila Cristina Ferreira da Costa

Full Text Available ABSTRACT Studies on the nesting biology of Liris are restricted to a few notes and observations on ground-nesting species. There are no studies of this kind about Brazilian species. We investigated and described the nesting biology of Liris sp. obtained by trap-nests that were installed at an area of Atlantic Forest vegetation (25°10'S, 48°18'W in southern Brazil. The nests of Liris sp. are built with a variety of plant debris. They usually have one cell, but may have up to two. Nests do not show vestibular or intercalary cells. Immatures have a hard cocoon made with the silk they produce, mixed with the fine sand and sawdust left by the adult female at the bottom of the cell. No nest parasites were observed. The wasps did not go through diapause at the prepupal stage, and emerged within 36 to 46 days after nests were collected from the field. There was no emergence of male wasps. Even though Liris sp. nest in preexisting cavities, they resemble ground-nesting species of the same genus in their habits, nest architecture, and development characteristics. The absence of males in our samples might be related to nest diameter. The eggs from which males hatch can be laid in smaller burrows than those available at the present study. We believe that the hardiness of the cocoon is the species' main strategy against parasites, although it is complemented by the camouflage provided by the nest closure. We suggest that a broader comparison of the nesting biology of Liris Fabricius, 1804 should be carried out, leading to a better understanding of the evolution of nests in the genus.

Eficiencia de dos pruebas diagnósticas en la determinación de alergia por ácaros en niños

Directory of Open Access Journals (Sweden)

Yadira Fuentes

2008-08-01

Full Text Available Las enfermedades alérgicas constituyen un problema de salud mundial y los ácaros se encuentran entre sus principales agentes etiológicos. En Cuba se destacan los siguientes: Dermatophagoides pteronyssinus, Dermatophagoides siboney y Blomia tropicalis. Con el objetivo de determinar la eficiencia de la prueba cutánea por punción y la determinación de IgE específica para el diagnóstico de la alergia a estos tres ácaros se desarrolló en el año 2003 un estudio analítico que incluyó 100 niños: 50 no alérgicos y 50 alérgicos que asistieron al Hospital Pediátrico "William Soler" de Ciudad de La Habana. A todos se les realizó la prueba cutánea por punción con tres extractos alergénicos (VALERGEN-DP, VALERGEN-DS y VALERGEN-BT y se les extrajo sangre para la valoración de la IgE ácaro específica; exámenes que mostraron una mayor positividad ante D. pteronyssinus en los niños enfermos. Mientras que en los no alérgicos la prueba cutánea y la IgE para D. pteronyssinus fueron negativas. La prueba cutánea presentó un 100% de especificidad, con una mayor sensibilidad para VALERGEN-DP (88%, extracto con más eficiencia diagnóstica (94%. La IgE expresó los mejores resultados de sensibilidad, especificidad y eficiencia para D. pteronyssinus (78, 100 y 89%, respectivamente. La prueba cutánea por punción fue más eficiente que la determinación de IgE específica para el diagnóstico de las alergias por ácaros. En los enfermos se observó una correlación significativa entre la respuesta cutánea y el nivel de IgE para los ácaros estudiados. Estos datos contribuyeron a mejorar el diagnóstico alergológico y alertan sobre la necesidad de extender el uso de la inmunoterapia específica con vacunas hiposensibilizantes en los niños alérgicos a los ácaros.

Harpy eagle (Harpia harpyja) nesting in manipulated forests

Science.gov (United States)

Alvarez, E.; Ellis, D.H.

1994-01-01

Continental records point to shooting, removal of young and destruction of nests as the primary conservation problems for harpy eagles (Harpia harpyja); bird-observer visits are a new source of concern. Nesting events are roughly 3 yr apart. Nests are used during and after intensive manipulation of the surrounding habitat, and minimum distance between active sites was 3-5 km. In nine nesting sites along a 100-km stretch of the Imalaca Mountains in Venezuela, we fitted five fledglings with satellite-tracked tags from NASA. One of these birds was hacked with the help of the loggers who destroyed its nest. All these nests were active while logging ensued. Out of three renesting attempts, one failed when the nest collapsed. We salvaged two additional fledglings found in captivity. We are monitoring five nests in the buffer area of the Darien National Park in Panama, all within 3 km of human settlements where trees are regularly felled for firewood, lumber, and to clear more cropland. Eagles have been killed at two sites, a third site remains inactive since 1991, and the other two nests currently have fledglings.

Simulating large-scale spiking neuronal networks with NEST

OpenAIRE

Schücker, Jannis; Eppler, Jochen Martin

2014-01-01

The Neural Simulation Tool NEST [1, www.nest-simulator.org] is the simulator for spiking neural networkmodels of the HBP that focuses on the dynamics, size and structure of neural systems rather than on theexact morphology of individual neurons. Its simulation kernel is written in C++ and it runs on computinghardware ranging from simple laptops to clusters and supercomputers with thousands of processor cores.The development of NEST is coordinated by the NEST Initiative [www.nest-initiative.or...

Jordan Isomorphisms on Nest Subalgebras

Directory of Open Access Journals (Sweden)

Aili Yang

2015-01-01

Full Text Available This paper is devoted to the study of Jordan isomorphisms on nest subalgebras of factor von Neumann algebras. It is shown that every Jordan isomorphism ϕ between the two nest subalgebras algMβ and algMγ is either an isomorphism or an anti-isomorphism.

Evaluación de la prueba de la moneda peruana en el tamizaje de trastorno cognitivo en adultos mayores

Directory of Open Access Journals (Sweden)

Teodoro J Oscanoa

2016-01-01

Full Text Available Objetivos. Adaptación peruana del test de la moneda en el tamizaje de trastorno cognitivo en adultos mayores (>60 años. Materiales y métodos. El presente es un estudio de fase I de evaluación de prueba diagnóstica con muestreo de conveniencia y calculo de sensibilidad y especificidad, con una prevalencia pretest de 50%. Para la definición operacional de pacientes con trastorno cognitivo se utilizó los criterios de la DSM IV (The Diagnostic and Statistical Manual of Mental Disorders y el Global Deterioration Scale (GDS (controles: GDS 1 y 2; casos: mayor de 2. Para encontrar el punto de corte se utilizó la curva ROC (Receiver Operating Characteristic. Resultados. Los pacientes estudiados fueron 42 casos y 42 controles, no hubo diferencia significativa entre la edad (77,88 + 6,01 y 76,14 + 6,49 años y años de educación (13,69 + 3,70 y 8,17 + 4,71. La versión peruana del "eurotest" denominada "prueba de la moneda peruana" tiene una sensibilidad de 90,5% y especificidad de 83,3 % con punto de corte de 24. Conclusiones. La versión peruana adaptada del "eurotest", denominada "prueba de la moneda peruana" podría ser útil en el tamizaje de trastorno cognitivo de adultos mayores.

Gregarious nesting - An anti-predator response in laying hens

DEFF Research Database (Denmark)

Riber, Anja Brinch

2012-01-01

Gregarious nesting can be defined as a behaviour that occurs when a laying hen (Gallus gallus domesticus) given the choice between an occupied and an unoccupied nest site chooses the occupied nest site. It occurs frequently in flocks of laying hens kept under commercial conditions, contrasting...... the behaviour displayed by feral hens that isolate themselves from the flock during nesting activities. What motivates laying hens to perform gregarious nesting is unknown. One possibility is that gregarious nesting is an anti-predator response to the risk of nest predation emerging from behavioural flexibility...

Trap-nests for stingless bees (Hymenoptera, Meliponini)

OpenAIRE

Oliveira , Ricardo; Menezes , Cristiano; Soares , Ademilson; Fonseca , Vera

2012-01-01

International audience; Most stingless bee species build their nests inside tree hollows. In this paper, we present trap-nest containers which simulate nesting cavities so as to attract swarms of stingless bees. Although regularly used by stingless bee beekeepers in Brazil, this technique to obtain new colonies has not yet been systematically studied. We used two different types of trap-nests (plastic and cardboard) of four different sizes (0.5, 1.0, 2.0, and 3.0 L) containing propolis extrac...

Effect of nest design, passages, and hybrid on use of nest and production performance of layers in furnished cages.

Science.gov (United States)

Wall, H; Tauson, R; Elwinger, K

2002-03-01

Production performance, including egg quality, and proportion of eggs laid in nests were studied in furnished experimental cages incorporating nests, litter baths, and perches. The study comprised a total of 972 hens of two genotypes: Lohmann Selected Leghorn (LSL) and Hy-Line White. The birds were studied from 20 to 80 wk of age, and conventional four-hen cages were included as a reference. In furnished cages for six hens, the effects of 30 or 50% vs. 100% nest bottom lining (Astro turf) were studied with LSL hens. Nest bottom lining had no significant effect on egg production or proportions of cracked or dirty eggs, but the use of nests was significantly higher in cages incorporating nests with 100% lining, compared with 50 or 30%. The two hybrids were compared when housed in large, group-furnished cages for 14 or 16 hens of two designs; with a rear partition with two pop holes or fully open, i.e., no rear partition. LSL birds produced significantly better and had a significantly lower proportion of cracked eggs. There was no difference between H- and O-cages, either in production or in egg quality. LSL birds laid a significantly lower proportion of eggs in the nests, especially in O-cages, implying a significant hybrid x cage interaction. When housed in conventional cages, the hybrids did not differ in proportion of cracked eggs but differed in production traits. It was concluded that with the present nest design, the proportion of nest bottom lining cannot be reduced without affecting birds' use of nests, but the proportion did not affect exterior egg quality. The effect of genotype should be considered in the further development of furnished cages.

Nesting success and within-season breeding dispersal in the ...

African Journals Online (AJOL)

Nest predation is a primary cause of nesting mortality for many bird species, particularly passerines. Nest location can affect predation, and it has also been demonstrated that predation risk can alter nest site selection. Birds can limit predation risk by selecting specific habitat characteristics; by changing nest site ...

Colour preferences in nest-building zebra finches.

Science.gov (United States)

Muth, Felicity; Steele, Matthew; Healy, Susan D

2013-10-01

Some bird species are selective in the materials they choose for nest building, preferring, for example, materials of one colour to others. However, in many cases the cause of these preferences is not clear. One of those species is the zebra finch, which exhibits strong preferences for particular colours of nest material. In an attempt to determine why these birds strongly prefer one colour of material over another, we compared the preferences of paired male zebra finches for nest material colour with their preferences for food of the same colours. We found that birds did indeed prefer particular colours of nest material (in most cases blue) but that they did not generally prefer food of one colour over the other colours. It appears, then, that a preference for one colour or another of nest material is specific to the nest-building context. This article is part of a Special Issue entitled: insert SI title. Copyright © 2013 Elsevier B.V. All rights reserved.

Signos Vitales de los CDC–La prueba del VIH (HIV Testing)

Centers for Disease Control (CDC) Podcasts

2017-11-28

Este podcast se basa en la edición de diciembre del 2017 del informe Signos Vitales de los CDC. En los Estados Unidos, alrededor del 15 por ciento de las personas que tienen el VIH no saben que lo tienen. Sepa la importancia que tiene hacerse la prueba, y recibir el diagnóstico y el tratamiento temprano.  Created: 11/28/2017 by Centers for Disease Control and Prevention (CDC).   Date Released: 11/28/2017.

Landscape distribution of food and nesting sites affect larval diet and nest size, but not abundance of Osmia bicornis.

Science.gov (United States)

Coudrain, Valérie; Rittiner, Sarah; Herzog, Felix; Tinner, Willy; Entling, Martin H

2016-10-01

Habitat fragmentation is a major threat for beneficial organisms and the ecosystem services they provide. Multiple-habitat users such as wild bees depend on both nesting and foraging habitat. Thus, they may be affected by the fragmentation of at least two habitat types. We investigated the effects of landscape-scale amount of and patch isolation from both nesting habitat (woody plants) and foraging habitat (specific pollen sources) on the abundance and diet of Osmia bicornis L. Trap-nests of O. bicornis were studied in 30 agricultural landscapes of the Swiss Plateau. Nesting and foraging habitats were mapped in a radius of 500 m around the sites. Pollen composition of larval diet changed as isolation to the main pollen source, Ranunculus, increased, suggesting that O. bicornis adapted its foraging strategy in function of the nest proximity to main pollen sources. Abundance of O. bicornis was neither related to isolation or amount of nesting habitat nor to isolation or abundance of food plants. Surprisingly, nests of O. bicornis contained fewer larvae in sites at forest edge compared to isolated sites, possibly due to higher parasitism risk. This study indicates that O. bicornis can nest in a variety of situations by compensating scarcity of its main larval food by exploiting alternative food sources. © 2015 Institute of Zoology, Chinese Academy of Sciences.

Turkey habitat use and nesting characteristics in ponderosa pine

Science.gov (United States)

Mark A. Rumble; Stanley H. Anderson

1987-01-01

Turkeys (Meleagris gallapovo) selected nest sites that provided good horizontal concealment. Rock or rock outcrops were selected most frequently for nest concealment on first-nest attempts. Renest attempts showed a selection preference for shrubs as nest cover; most of these were located in meadows. Nesting success doubled for renests versus first...

Response of predators to Western Sandpiper nest exclosures

Science.gov (United States)

Niehaus, Amanda C.; Ruthrauff, Daniel R.; McCaffery, Brian J.

2004-01-01

In 2001, predator exclosures were used to protect nests of the Western Sandpiper (Calidris mauri) in western Alaska. During the exclosure experiment, nest contents in exclosures had significantly higher daily survival rates than control nests, however, late in the study predators began to cue in on exclosures and predate the nest contents. An Arctic Fox (Alopex lagopus) dug under one exclosure and took the newly hatched chicks, and Long-tailed Jaegers (Stercorarius longicaudus) learned to associate exclosures with active nests and repeatedly visited them. The jaegers attempted to gain access to exclosed nests and pursued adult sandpipers as they emerged from the exclosures. The exclosures were removed to reduce potential mortality to adult and young sandpipers, but subsequently, post-exclosure nests had lower daily survival rates than controls during the same time period. Predation of post-exclosure eggs and chicks highlighted the lasting influence of the exclosure treatment on offspring survival because predators probably remembered nest locations. Researchers are urged to use caution when considering use of predator exclosures in areas where jaegers occur.

Incorporation of cigarette butts into nests reduces nest ectoparasite load in urban birds: new ingredients for an old recipe?

Science.gov (United States)

Suárez-Rodríguez, Monserrat; López-Rull, Isabel; Garcia, Constantino Macías

2013-02-23

Birds are known to respond to nest-dwelling parasites by altering behaviours. Some bird species, for example, bring fresh plants to the nest, which contain volatile compounds that repel parasites. There is evidence that some birds living in cities incorporate cigarette butts into their nests, but the effect (if any) of this behaviour remains unclear. Butts from smoked cigarettes retain substantial amounts of nicotine and other compounds that may also act as arthropod repellents. We provide the first evidence that smoked cigarette butts may function as a parasite repellent in urban bird nests. The amount of cellulose acetate from butts in nests of two widely distributed urban birds was negatively associated with the number of nest-dwelling parasites. Moreover, when parasites were attracted to heat traps containing smoked or non-smoked cigarette butts, fewer parasites reached the former, presumably due to the presence of nicotine. Because urbanization changes the abundance and type of resources upon which birds depend, including nesting materials and plants involved in self-medication, our results are consistent with the view that urbanization imposes new challenges on birds that are dealt with using adaptations evolved elsewhere.

Pruebas electrónicas ante los tribunales en la lucha contra la cibercriminalidad. Un proyecto europeo

Directory of Open Access Journals (Sweden)

Fredesvinda Insa Mérida

2008-05-01

Full Text Available ResumenLa admisibilidad de las pruebas electrónicas en los tribunales en Europa queda regulada a través de disposiciones generales aplicables a la prueba tradicional, sin que, hasta el presente, exista ninguna regulación nacional específica en el viejo continente. Las percepciones manifestadas por los propios actores sociales implicados en el proceso de obtención, presentación y admisión de las pruebas electrónicas de cara a un juicio, junto con el vacío legislativo dominante, generan cierta inseguridad jurídica y profesional. En consecuencia, este proyecto refleja la carencia –aludida por los actores del mundo legal, empresarial y tecnológico– de una formación, cualificación y regulación específicas para permitir una mejor actuación de estos profesionales europeos, a fin de proteger mejor a las víctimas de los delitos cometidos a través de las tecnologías de información.AbstractThe admission of electronic evidence in European courts is regulated through general dispositions applicable to traditional proof, without any specific national regulation in the Old Continent. Perceptions manifested by social actors implicated in the process of gathering, presentation and admission of electronic proofs for a trial, as well as the dominant judicial vacuum, generate some judicial and professional insecurity. As a consequence, this project reflects the lack –highlighted by authors in the legal, entrepreneurial and technological world– of a specific formation, qualification and regulation to allow a better performance for these European professionals, with the goal of better protecting victims of felonies carried on through New Technologies.

Semantic Analysis of Virtual Classes and Nested Classes

DEFF Research Database (Denmark)

Madsen, Ole Lehrmann

1999-01-01

Virtual classes and nested classes are distinguishing features of BETA. Nested classes originated from Simula, but until recently they have not been part of main stream object- oriented languages. C++ has a restricted form of nested classes and they were included in Java 1.1. Virtual classes...... classes and parameterized classes have been made. Although virtual classes and nested classes have been used in BETA for more than a decade, their implementation has not been published. The purpose of this paper is to contribute to the understanding of virtual classes and nested classes by presenting...

Demand for Neste's City products grows strongly

International Nuclear Information System (INIS)

Anon.

1994-01-01

Finland's oil, chemicals, and gas company, Neste Corporation, is well on the road to better financial performance after a very difficult year in 1992. Among the factors contributing to this optimism are Neste's pioneering low environmental impact traffic fuels. Neste Corporation's net sales in 1993 rose 9.9 % on 1992 figures to USD 11,011 million. Investments totalled USD 681 million. Profitability also improved during 1993, and the operating margin rose by 57 %, despite the recession affecting the Finnish economy and the instability of the international market. The operational loss for the year before extraordinary items, reserves, and taxes was USD 265 million, one-third less than in 1992. Neste's strategy has been to achieve a strong position in the Baltic Rim region by becoming the quality and cost leader in oil refining, and by expanding Neste's position in its key markets. A total of 3.3 million tonnes of petroleum products were exported from Finland in 1993. Neste's most important export markets were Sweden, Germany, Poland, the Baltic countries, and the St. Petersburg region. Some 20 % of exports went to customers outside Europe. In addition to Finland, Neste has concertedly developed its service station network in Poland and the Baltic countries

UBV-photometry of nests of interacting galaxies

International Nuclear Information System (INIS)

Arkhipova, V.P.

1982-01-01

The results of photoelectric UBV-observations of 19 nests of interacting galaxies, made at the Crimean Station of the Sternberg Institute, are given. Most of the nests observed were found to be and to have high luminosity. The UBV and spectral data show a large amount of gas inside many nests [ru

Advantages of the synthetic technique for the conduction of short circuit tests to breakers; Ventajas de la tecnica sintetica para realizar pruebas de corto circuito a interruptores

Energy Technology Data Exchange (ETDEWEB)

Sibilski, Henry [Instituto Electrotecnico de Varsovia, Varsovia (Poland); Ochoa Vivanco, Ruben [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)

1987-12-31

In this article the operational principle of the synthetic test is described; specifically of the current injection circuit in parallel. Its utilization in the research and development of new breaker models and its wide possibilities regarding its testing characteristics is outlined. Likewise the different tests that can be performed by means of the synthetic technique are described. Finally the importance of the synthetic tests is outlined for the development of own technology in the area of interruption equipment and emphasis is made that in industrialized countries this technique is of common practice. [Espanol] En este articulo se describe el principio de operacion de la prueba sintetica; especificamente del circuito de inyeccion de corriente en paralelo. Se destaca su utilizacion en la investigacion y desarrollo de nuevos modelos de interruptores y sus amplias posibilidades en cuanto a caracteristicas de prueba. Asimismo, se describen las diferentes pruebas que pueden realizarse mediante la tecnica sintetica. Por ultimo, se destaca la importancia de las pruebas sinteticas para el desarrollo de tecnologia propia en el area de equipos de interrupcion, y se hace notar que en paises desarrollados, esta tecnica es practica comun.

Advantages of the synthetic technique for the conduction of short circuit tests to breakers; Ventajas de la tecnica sintetica para realizar pruebas de corto circuito a interruptores

Energy Technology Data Exchange (ETDEWEB)

Sibilski, Henry [Instituto Electrotecnico de Varsovia, Varsovia (Poland); Ochoa Vivanco, Ruben [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)

1986-12-31

In this article the operational principle of the synthetic test is described; specifically of the current injection circuit in parallel. Its utilization in the research and development of new breaker models and its wide possibilities regarding its testing characteristics is outlined. Likewise the different tests that can be performed by means of the synthetic technique are described. Finally the importance of the synthetic tests is outlined for the development of own technology in the area of interruption equipment and emphasis is made that in industrialized countries this technique is of common practice. [Espanol] En este articulo se describe el principio de operacion de la prueba sintetica; especificamente del circuito de inyeccion de corriente en paralelo. Se destaca su utilizacion en la investigacion y desarrollo de nuevos modelos de interruptores y sus amplias posibilidades en cuanto a caracteristicas de prueba. Asimismo, se describen las diferentes pruebas que pueden realizarse mediante la tecnica sintetica. Por ultimo, se destaca la importancia de las pruebas sinteticas para el desarrollo de tecnologia propia en el area de equipos de interrupcion, y se hace notar que en paises desarrollados, esta tecnica es practica comun.

Eggshell Porosity Provides Insight on Evolution of Nesting in Dinosaurs.

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Kohei Tanaka

Full Text Available Knowledge about the types of nests built by dinosaurs can provide insight into the evolution of nesting and reproductive behaviors among archosaurs. However, the low preservation potential of their nesting materials and nesting structures means that most information can only be gleaned indirectly through comparison with extant archosaurs. Two general nest types are recognized among living archosaurs: 1 covered nests, in which eggs are incubated while fully covered by nesting material (as in crocodylians and megapodes, and 2 open nests, in which eggs are exposed in the nest and brooded (as in most birds. Previously, dinosaur nest types had been inferred by estimating the water vapor conductance (i.e., diffusive capacity of their eggs, based on the premise that high conductance corresponds to covered nests and low conductance to open nests. However, a lack of statistical rigor and inconsistencies in this method render its application problematic and its validity questionable. As an alternative we propose a statistically rigorous approach to infer nest type based on large datasets of eggshell porosity and egg mass compiled for over 120 extant archosaur species and 29 archosaur extinct taxa/ootaxa. The presence of a strong correlation between eggshell porosity and nest type among extant archosaurs indicates that eggshell porosity can be used as a proxy for nest type, and thus discriminant analyses can help predict nest type in extinct taxa. Our results suggest that: 1 covered nests are likely the primitive condition for dinosaurs (and probably archosaurs, and 2 open nests first evolved among non-avian theropods more derived than Lourinhanosaurus and were likely widespread in non-avian maniraptorans, well before the appearance of birds. Although taphonomic evidence suggests that basal open nesters (i.e., oviraptorosaurs and troodontids were potentially the first dinosaurs to brood their clutches, they still partially buried their eggs in sediment

Eggshell Porosity Provides Insight on Evolution of Nesting in Dinosaurs.

Science.gov (United States)

Tanaka, Kohei; Zelenitsky, Darla K; Therrien, François

2015-01-01

Knowledge about the types of nests built by dinosaurs can provide insight into the evolution of nesting and reproductive behaviors among archosaurs. However, the low preservation potential of their nesting materials and nesting structures means that most information can only be gleaned indirectly through comparison with extant archosaurs. Two general nest types are recognized among living archosaurs: 1) covered nests, in which eggs are incubated while fully covered by nesting material (as in crocodylians and megapodes), and 2) open nests, in which eggs are exposed in the nest and brooded (as in most birds). Previously, dinosaur nest types had been inferred by estimating the water vapor conductance (i.e., diffusive capacity) of their eggs, based on the premise that high conductance corresponds to covered nests and low conductance to open nests. However, a lack of statistical rigor and inconsistencies in this method render its application problematic and its validity questionable. As an alternative we propose a statistically rigorous approach to infer nest type based on large datasets of eggshell porosity and egg mass compiled for over 120 extant archosaur species and 29 archosaur extinct taxa/ootaxa. The presence of a strong correlation between eggshell porosity and nest type among extant archosaurs indicates that eggshell porosity can be used as a proxy for nest type, and thus discriminant analyses can help predict nest type in extinct taxa. Our results suggest that: 1) covered nests are likely the primitive condition for dinosaurs (and probably archosaurs), and 2) open nests first evolved among non-avian theropods more derived than Lourinhanosaurus and were likely widespread in non-avian maniraptorans, well before the appearance of birds. Although taphonomic evidence suggests that basal open nesters (i.e., oviraptorosaurs and troodontids) were potentially the first dinosaurs to brood their clutches, they still partially buried their eggs in sediment. Open nests

EFECTO ANTINOCICEPTIVO DEL EXTRACTO ETANÓLICO DE LAS HOJAS DE MAYTENUS MACROCARPA (RUIZ & PAV.) BRIQ. “CHUCHUHUASI” MEDIANTE LA PRUEBA DE CONTORSIONES ABDOMINALES EN RATONES.

OpenAIRE

V Robles-Pizarro; L Tarqui-Cabrera; N Rodríguez-Collazos; A Morales-Chau; J De La Cruz-Manyari; K Ríos-Melgar; D Rivera-Cruzado; A Rubio-Gonzáles; C Santa Cruz-Contreras; G Velazco-Curay; B Loja-Herrera; A Alvarado-Yarasca; B Castañeda-Castañeda; A Salazar-Granara

2014-01-01

OBJETIVODeterminar el efecto y actividad antinociceptiva de las hojas de Maytenus macrocarpa (Ruiz & Pav) Briq. “chuchuhuasi” mediante la prueba de contorsiones abdominales en roedor.MATERIAL Y MÉTODOSe utilizaron 40 ratones albinos machos, con pesos medios de 25g, se empleó la prueba de contorsiones abdominales para determinar la actividad antinociceptiva. El grupo Control, no recibió ninguna sustancia. Se administró extracto etanólico de las hojas de M. macrocarpa (Ruiz & Pav.) Briq...

Nest Success and Cause-Specific Nest Failure of Grassland Passerines Breeding in Prairie Grazed by Livestock

Science.gov (United States)

This manuscript describes two years of field research on ground-nesting songbird species at Zumwalt Prairie Reserve, northeastern Oregon, USA. Cattle-grazing has long been suspected in declines of ground-nesting songbirds in grazed grassland, primarily due to increased trampling...

Fiber Tracking Cylinder Nesting

International Nuclear Information System (INIS)

Stredde, H.

1999-01-01

The fiber tracker consists of 8 concentric carbon fiber cylinders of varying diameters, from 399mm to 1032.2mm and two different lengths. 1.66 and 2.52 meters. Each completed cylinder is covered over the entire o.d. with scintillating fiber ribbons with a connector on each ribbon. These ribbons are axial (parallel to the beam line) at one end and stereo (at 3 deg. to the beam line) at the other. The ribbon connectors have dowel pins which are used to match with the connectors on the wave guide ribbons. These dowel pins are also used during the nesting operation, locating and positioning measurements. The nesting operation is the insertion of one cylinder into another, aligning them with one another and fastening them together into a homogeneous assembly. For ease of assembly. the nesting operation is accomplished working from largest diameter to smallest. Although the completed assembly of all 8 cylinders glued and bolted together is very stiff. individual cylinders are relatively flexible. Therefore. during this operation, No.8 must be supported in a manner which maintains its integrity and yet allows the insertion of No.7. This is accomplished by essentially building a set of dummy end plates which replicate a No.9 cylinder. These end plates are mounted on a wheeled cart that becomes the nesting cart. Provisions for a protective cover fastened to these rings has been made and will be incorporated in finished product. These covers can be easily removed for access to No.8 and/or the connection of No.8 to No.9. Another wheeled cart, transfer cart, is used to push a completed cylinder into the cylinder(s) already mounted in the nesting cart.

Pruebas de velocidad aeróbica máxima con jóvenes futbolistas. Control y programación de la intensidad de los entrenamientos

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Philippe Campillo

2013-09-01

Full Text Available Se ha realizado un estudio comparativo para analizar la importancia del entrenamiento intermitente, más precisamente la utilización de la velocidad aeróbica máxima (VAM intermitente en la práctica del fútbol. Se ha evaluado la VAM continua con la prueba VAMEVAL (evaluación de la velocidad máxima aeróbica y la VAM intermitente con la prueba 45-15 con ayuda de 21 jóvenes futbolistas. Teniendo en cuenta los resultados se han formado dos grupos homogéneos que realizan un ciclo de siete semanas de entrenamiento específico con el objetivo de desarrollar la PMA. La intensidad del entrenamiento del grupo 1 tiene como referencia el nivel máximo de la VAM continua y el de la VAM intermitente para el grupo 2. Para el conjunto de los jugadores, y para cada grupo, se observa una diferencia significativa inicial (p < 0,001 entre la VAM intermitente (16,02 ± 1,21 km/h y la VAM continua (14,12 ± 1,06 km/h. Finalizado el ciclo se mantienen las mismas diferencias entre las VAM intermitentes y continuas. Sin embargo, para el grupo 1 no hay diferencias significativas entre las dos pruebas 45-15 inicial y final; por el contrario, para el grupo 2 existe una clara diferencia (p < 0,01 entre las dos pruebas intermitentes (15,86 ± 1,50 km/h / 17,0 ± 0,97 km/h. Aunque los dos grupos han mejorado su VAM continua se observa un aumento superior de la velocidad en el grupo 2. Es muy importante tener en cuenta los resultados de las pruebas de VAM continua y sobre todo intermitente para programar y adaptar con precisión la intensidad de los entrenamientos, puesto que existen diferencias que no siempre se valoran.

Sistema para la Aplicación de Pruebas Psicológicas vía Web

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Cuauhtémoc Hidalgo-Cortés

2012-05-01

Full Text Available In this work, we present a generic Web system for the application, capturing and editing ofany multiple-choice psychological test capable of storing data permanently (in order to makecomparative and longitudinal studies. Also, these data can be imported into other statisticalprograms such as Microsoft Excel, SPSS and Origin. The implementation and administrationof the tests can be done from any Internet-connected computer without installing specializedsoftware. To evaluate the potential of this system, the questionnaire Cuestionario Honey-Alonsode Estilos de Aprendizaje (C. H. A. E. A. was captured and applied to 255 subjects. Theresults showed a significant reduction in time spent calculating the factor, in the same way,the total score for each test also prevented the occurrence of errors made by human interventionin the assessment manual (since this process was automated by the system.En este trabajo se presenta un sistema web para la aplicación, captura y edición de cual­quier prueba psicológica de opción múltiple con capacidad para almacenar datos de forma permanente (dicha información permitirá llevar a cabo estudios comparativos y longitudi­nales. De la misma forma, los datos almacenados pueden ser importados por otros pro­gramas estadísticos, como por ejemplo Microsoft Excel, SPSS y Origin. La aplicación y administración de estas pruebas puede hacerse desde cualquier computadora conectada a la Internet sin necesidad de instalar programas especializados. Para evaluar el potencial de este sistema, se capturó el Cuestionario Honey-Alonso de Estilos de Aprendizaje (C. H. A. E. A. y se aplicó a 255 sujetos. Los resultados obtenidos demuestran una reducción considerable en el tiempo invertido en el cálculo de las subescalas (factor y en la puntuación total de cada prueba, además, se evitó la aparición de errores cometidos por la intervención huma­na en la evaluación manual (debido a que este proceso fue automatizado por

Predaceous ants, beach replenishment, and nest placement by sea turtles.

Science.gov (United States)

Wetterer, James K; Wood, Lawrence D; Johnson, Chris; Krahe, Holly; Fitchett, Stephanie

2007-10-01

Ants known for attacking and killing hatchling birds and reptiles include the red imported fire ant (Solenopsis invicta Buren), tropical fire ant [Solenopsis geminata (Fabr.)], and little fire ant [Wasmannia auropunctata (Roger)]. We tested whether sea turtle nest placement influenced exposure to predaceous ants. In 2000 and 2001, we surveyed ants along a Florida beach where green turtles (Chelonia mydas L.), leatherbacks (Dermochelys coriacea Vandelli), and loggerheads (Caretta caretta L.) nest. Part of the beach was artificially replenished between our two surveys. As a result, mean beach width experienced by nesting turtles differed greatly between the two nesting seasons. We surveyed 1,548 sea turtle nests (2000: 909 nests; 2001: 639 nests) and found 22 ant species. S. invicta was by far the most common species (on 431 nests); S. geminata and W. auropunctata were uncommon (on 3 and 16 nests, respectively). In 2000, 62.5% of nests had ants present (35.9% with S. invicta), but in 2001, only 30.5% of the nests had ants present (16.4% with S. invicta). Turtle nests closer to dune vegetation had significantly greater exposure to ants. Differences in ant presence on turtle nests between years and among turtle species were closely related to differences in nest placement relative to dune vegetation. Beach replenishment significantly lowered exposure of nests to ants because on the wider beaches turtles nested farther from the dune vegetation. Selective pressures on nesting sea turtles are altered both by the presence of predaceous ants and the practice of beach replenishment.

Lesser prairie-chicken nest site selection, microclimate, and nest survival in association with vegetation response to a grassland restoration program

Science.gov (United States)

Boal, Clint W.; Grisham, Blake A.; Haukos, David A.; Zavaleta, Jennifer C.; Dixon, Charles

2014-01-01

Climate models predict that the region of the Great Plains Landscape Conservation Cooperative (GPLCC) will experience increased maximum and minimum temperatures, reduced frequency but greater intensity of precipitation events, and earlier springs. These climate changes along with different landscape management techniques may influence the persistence of the lesser prairie-chicken (Tympanuchus pallidicinctus), a candidate for protection under the Endangered Species Act and a priority species under the GPLCC, in positive or negative ways. The objectives of this study were to conduct (1) a literature review of lesser prairie-chicken nesting phenology and ecology, (2) an analysis of thermal aspects of lesser prairie-chicken nest microclimate data, and (3) an analysis of nest site selection, nest survival, and vegetation response to 10 years of tebuthiuron and/or grazing treatments. We found few reports in the literature containing useful data on the nesting phenology of lesser prairie-chickens; therefore, managers must rely on short-term observations and measurements of parameters that provide some predictive insight into climate impacts on nesting ecology. Our field studies showed that prairie-chickens on nests were able to maintain relatively consistent average nest temperature of 31 °C and nest humidities of 56.8 percent whereas average external temperatures (20.3–35.0 °C) and humidities (35.2–74.9 percent) varied widely throughout the 24 hour (hr) cycle. Grazing and herbicide treatments within our experimental areas were designed to be less intensive than in common practice. We determined nest locations by radio-tagging hen lesser prairie-chickens captured at leks, which are display grounds at which male lesser prairie-chickens aggregate and attempt to attract a female for mating. Because nest locations selected by hen lesser prairie-chicken are strongly associated with the lek at which they were captured, we assessed nesting habitat use on the basis of hens

Confiabilidad de pruebas para flexibilidad en futbolistas jóvenes de un club profesional [Reliability of Flexibility Tests in Young Soccer Players From a Professional Club

Directory of Open Access Journals (Sweden)

Cristian Díaz-Escobar

2018-01-01

Full Text Available Objetivo. Estimar la confiabilidad de pruebas para medir la flexibilidad de la musculatura flexoextensora de la rodilla, de acuerdo con la temporada, la edad y la posición de juego en jugadores varones del área formativa de un club profesional de fútbol. Material y métodos. La medición de la flexibilidad se realizó mediante la aplicación de las pruebas Modified. Thomas Test (MT Test para cuádriceps y el Modified Back-Saber Sit-and-Reach Test (MBS Test para isquiotibiales. La confiabilidad se estimó mediante el α de Cronbach. Resultados. Ambas pruebas presentaron estimaciones altas de confiabilidad entre temporadas, por categorías de jugadores, puesto de juego y en comparación del rendimiento entre miembro inferior derecho e izquierdo. Conclusiones. Ambas pruebas pueden ser aplicadas en deportes colectivos, como acontece en el área formativa de clubes profesionales de fútbol, especialmente, en la prevención de lesiones deportivas, al tener una validez aceptada, presentar una alta confiabilidad de acuerdo con el estudio y además, tener como características: bajo costo, fácil aplicación y medir un volumen importante de personas en breves periodos de tiempo.

Conocimientos, actitudes y prácticas sobre la prueba de Papanicolaou

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Fernando Bazán

2007-03-01

Full Text Available Objetivos: Determinar los conocimientos, actitudes y prácticas con respecto a la prueba de Papanicolaou (Pap; hallar la asociación entre la edad y grado de instrucción frente a dichas variables y describir las características sobre la práctica periódica del Pap. Diseño: Analítico y transversal. Lugar: Hospital Nacional Docente Madre-Niño ‘San Bartolomé’. Pacientes: Mujeres en edad fértil de consultorios externos. Intervenciones: Cuestionario estructurado, auto-desarrollado, durante noviembre-2005 a enero-2006. Para el análisis estadístico se utilizó: X2, t student, Anova y OR. Principales medidas de resultados: Nivel de conocimientos, actitudes y prácticas en mujeres sobre el Pap, y asociaciones y características sobre su práctica periódica. Resultados: De 501 encuestadas, en 63% se encontró nivel bajo de conocimiento, en 66% una actitud desfavorable y en 71% una práctica incorrecta sobre la prueba de Papanicolaou; se obtuvo un OR = 1,45 (IC = 0,98 a 2,16 entre el nivel de conocimiento y la práctica correcta; la difusión por los medios de comunicación sobre el Pap fue 6,2% y la mayor barrera para no tener una práctica periódica del Pap fue el género masculino del ejecutor (34,2%. Conclusiones: Los niveles de conocimiento, actitudes y prácticas, en nuestra población, son bajos. El mayor nivel de conocimiento no está relacionado con la práctica correcta del Pap. Existe poca difusión sobre el Pap por los medios de comunicación y las limitantes a que las mujeres se tomen el Pap son principalmente psicológicas.

Nest suitability, fine-scale population structure and male-mediated dispersal of a solitary ground nesting bee in an urban landscape.

Science.gov (United States)

López-Uribe, Margarita M; Morreale, Stephen J; Santiago, Christine K; Danforth, Bryan N

2015-01-01

Bees are the primary pollinators of flowering plants in almost all ecosystems. Worldwide declines in bee populations have raised awareness about the importance of their ecological role in maintaining ecosystem functioning. The naturally strong philopatric behavior that some bee species show can be detrimental to population viability through increased probability of inbreeding. Furthermore, bee populations found in human-altered landscapes, such as urban areas, can experience lower levels of gene flow and effective population sizes, increasing potential for inbreeding depression in wild bee populations. In this study, we investigated the fine-scale population structure of the solitary bee Colletes inaequalis in an urbanized landscape. First, we developed a predictive spatial model to detect suitable nesting habitat for this ground nesting bee and to inform our field search for nests. We genotyped 18 microsatellites in 548 female individuals collected from nest aggregations throughout the study area. Genetic relatedness estimates revealed that genetic similarity among individuals was slightly greater within nest aggregations than among randomly chosen individuals. However, genetic structure among nest aggregations was low (Nei's GST = 0.011). Reconstruction of parental genotypes revealed greater genetic relatedness among females than among males within nest aggregations, suggesting male-mediated dispersal as a potentially important mechanism of population connectivity and inbreeding avoidance. Size of nesting patch was positively correlated with effective population size, but not with other estimators of genetic diversity. We detected a positive trend between geographic distance and genetic differentiation between nest aggregations. Our landscape genetic models suggest that increased urbanization is likely associated with higher levels of inbreeding. Overall, these findings emphasize the importance of density and distribution of suitable nesting patches for enhancing

Nest suitability, fine-scale population structure and male-mediated dispersal of a solitary ground nesting bee in an urban landscape.

Directory of Open Access Journals (Sweden)

Margarita M López-Uribe

Full Text Available Bees are the primary pollinators of flowering plants in almost all ecosystems. Worldwide declines in bee populations have raised awareness about the importance of their ecological role in maintaining ecosystem functioning. The naturally strong philopatric behavior that some bee species show can be detrimental to population viability through increased probability of inbreeding. Furthermore, bee populations found in human-altered landscapes, such as urban areas, can experience lower levels of gene flow and effective population sizes, increasing potential for inbreeding depression in wild bee populations. In this study, we investigated the fine-scale population structure of the solitary bee Colletes inaequalis in an urbanized landscape. First, we developed a predictive spatial model to detect suitable nesting habitat for this ground nesting bee and to inform our field search for nests. We genotyped 18 microsatellites in 548 female individuals collected from nest aggregations throughout the study area. Genetic relatedness estimates revealed that genetic similarity among individuals was slightly greater within nest aggregations than among randomly chosen individuals. However, genetic structure among nest aggregations was low (Nei's GST = 0.011. Reconstruction of parental genotypes revealed greater genetic relatedness among females than among males within nest aggregations, suggesting male-mediated dispersal as a potentially important mechanism of population connectivity and inbreeding avoidance. Size of nesting patch was positively correlated with effective population size, but not with other estimators of genetic diversity. We detected a positive trend between geographic distance and genetic differentiation between nest aggregations. Our landscape genetic models suggest that increased urbanization is likely associated with higher levels of inbreeding. Overall, these findings emphasize the importance of density and distribution of suitable nesting

Importance of structural stability to success of mourning dove nests

Science.gov (United States)

Coon, R.A.; Nichols, J.D.; Percival, H.F.

1981-01-01

Studies of nest-site selection and nesting habitats often involve a "characterization" of nests and of habitats in which nests are found. Our objective in the present work is to identify nest-site characteristics that are associated with variation in components of Mourning Dove (Zenaida macroura) fitness (e.g. the probability of a nest succeeding), as opposed to simply "characterizing" dove nest sites. If certain nest- site characteristics affect the probability that a nest will succeed, then we suspect that these characteristics will be associated with either concealment (the probability of detection by certain predators) or structural stability (the probability of eggs or entire nests falling to the ground as a result of wind, rain storms, parental activity, etc.). Although other workers agree that structural stability is an important determinant of Mourning Dove nesting success (e.g. McClure 1944: 384; Woolfenden and Rohwer 1969: 59), we are aware of no actual tests of this hypothesis.

The effects of large beach debris on nesting sea turtles

Science.gov (United States)

Fujisaki, Ikuko; Lamont, Margaret M.

2016-01-01

A field experiment was conducted to understand the effects of large beach debris on sea turtle nesting behavior as well as the effectiveness of large debris removal for habitat restoration. Large natural and anthropogenic debris were removed from one of three sections of a sea turtle nesting beach and distributions of nests and false crawls (non-nesting crawls) in pre- (2011–2012) and post- (2013–2014) removal years in the three sections were compared. The number of nests increased 200% and the number of false crawls increased 55% in the experimental section, whereas a corresponding increase in number of nests and false crawls was not observed in the other two sections where debris removal was not conducted. The proportion of nest and false crawl abundance in all three beach sections was significantly different between pre- and post-removal years. The nesting success, the percent of successful nests in total nesting attempts (number of nests + false crawls), also increased from 24% to 38%; however the magnitude of the increase was comparably small because both the number of nests and false crawls increased, and thus the proportion of the nesting success in the experimental beach in pre- and post-removal years was not significantly different. The substantial increase in sea turtle nesting activities after the removal of large debris indicates that large debris may have an adverse impact on sea turtle nesting behavior. Removal of large debris could be an effective restoration strategy to improve sea turtle nesting.

Comprehensive Comparison between Empty Nest and Non-Empty Nest Elderly: A Cross-Sectional Study among Rural Populations in Northeast China

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Ye Chang

2016-08-01

Full Text Available This study aimed to comprehensively compare the general characteristics, lifestyles, serum parameters, ultrasonic cardiogram (UCG parameters, depression, quality of life, and various comorbidities between empty nest and non-empty nest elderly among rural populations in northeast China. This analysis was based on our previous study which was conducted from January 2012 to August 2013, using a multistage, stratified, random cluster sampling scheme. The final analyzed sample consisted of 3208 participants aged no less than 60 years, which was further classified into three groups: non-empty nest group, empty nest group (living as a couple, and empty nest group (living alone. More than half of the participants were empty nest elderly (60.5%. There were no significant statistical differences for serum parameters, UCG parameters, lifestyles, dietary pattern, and scores of Patient Health Questionnaire-9 (PHQ-9 and World Health Organization Quality of Life questionnaire, abbreviated version (WHOQOL-BREF among the three groups. Empty nest elderly showed no more risk for comorbidities such as general obesity, abdominal obesity, hyperuricemia, hyperhomocysteinemia, diabetes, dyslipidemia, left atrial enlargement (LAE, and stroke. Our study indicated that empty nest elderly showed no more risk for depression, low quality of life and comorbidities such as general obesity, abdominal obesity, hyperuricemia, hyperhomocysteinemia, diabetes, dyslipidemia, LAE, and stroke among rural populations in northeast China.

Habitat and nesting biology of Mountain Plovers in Wyoming

Science.gov (United States)

Plumb, R.E.; Anderson, S.H.; Knopf, F.L.

2005-01-01

Although previous research has considered habitat associations and breeding biology of Mountain Plovers in Wyoming at discrete sites, no study has considered these attributes at a statewide scale. We located 55 Mountain Plover nests in 6 counties across Wyoming during 2002 and 2003. Nests occurred in 2 general habitat types: grassland and desert-shrub. Mean estimated hatch date was 26 June (n = 31) in 2002 and 21 June (n = 24) in 2003. Mean hatch date was not related to latitude or elevation. Hatch success of nests was inferred in 2003 by the presence of eggshell fragments in the nest scrape. Eggs in 14 of 22 (64%) known-fate nests hatched. All grassland sites and 90% of desert sites were host to ungulate grazers, although prairie dogs were absent at 64% of nest sites. Nest plots had less grass coverage and reduced grass height compared with random plots. More than 50% of nests occurred on elevated plateaus. The Mountain Plover's tendency to nest on arid, elevated plateaus further substantiates claims that the bird is also a disturbed-prairie species.

Superposition Enhanced Nested Sampling

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Stefano Martiniani

2014-08-01

Full Text Available The theoretical analysis of many problems in physics, astronomy, and applied mathematics requires an efficient numerical exploration of multimodal parameter spaces that exhibit broken ergodicity. Monte Carlo methods are widely used to deal with these classes of problems, but such simulations suffer from a ubiquitous sampling problem: The probability of sampling a particular state is proportional to its entropic weight. Devising an algorithm capable of sampling efficiently the full phase space is a long-standing problem. Here, we report a new hybrid method for the exploration of multimodal parameter spaces exhibiting broken ergodicity. Superposition enhanced nested sampling combines the strengths of global optimization with the unbiased or athermal sampling of nested sampling, greatly enhancing its efficiency with no additional parameters. We report extensive tests of this new approach for atomic clusters that are known to have energy landscapes for which conventional sampling schemes suffer from broken ergodicity. We also introduce a novel parallelization algorithm for nested sampling.

Using survival analysis of artificial and Real Brewer's sparrow (Spizella breweri breweri) nests to model site level and nest site factors associated with nest success in the South Okanagan region of Canada

Science.gov (United States)

Pam Krannitz Kym Welstead

2005-01-01

Predation is the predominant cause of nest failure for the Brewer's Sparrow (Spizella breweri breweri), a provincially red-listed shrub-steppe species that has experienced significant declines throughout most of its range. We monitored Brewer’s Sparrow nests and conducted an artificial nest experiment, in the South Okanagan Valley,...

Hurricane disturbance benefits nesting American Oystercatchers (Haematopus palliatus)

Science.gov (United States)

Simons, Theodore R.; Schulte, Shiloh A.

2016-01-01

Coastal ecosystems are under increasing pressure from human activity, introduced species, sea level rise, and storm activity. Hurricanes are a powerful destructive force, but can also renew coastal habitats. In 2003, Hurricane Isabel altered the barrier islands of North Carolina, flattening dunes and creating sand flats. American Oystercatchers (Haematopus palliatus) are large shorebirds that inhabit the coastal zone throughout the year. Alternative survival models were evaluated for 699 American Oystercatcher nests on North Core Banks and South Core Banks, North Carolina, USA, from 1999–2007. Nest survival on North Core Banks increased from 0.170 (SE = 0.002) to 0.772 (SE = 0.090) after the hurricane, with a carry-over effect lasting 2 years. A simple year effects model described nest survival on South Core Banks. Habitat had no effect on survival except when the overall rate of nest survival was at intermediate levels (0.300–0.600), when nests on open flats survived at a higher rate (0.600; SE = 0.112) than nests in dune habitat (0.243; SE = 0.094). Predator activity declined on North Core Banks after the hurricane and corresponded with an increase in nest survival. Periodic years with elevated nest survival may offset low annual productivity and contribute to the stability of American Oystercatcher populations.

Canada goose nest survival at rural wetlands in north-central Iowa

Science.gov (United States)

Ness, Brenna N.; Klaver, Robert W.

2016-01-01

The last comprehensive nest survival study of the breeding giant Canada goose (Branta canadensis maxima) population in Iowa, USA, was conducted >30 years ago during a period of population recovery, during which available nesting habitat consisted primarily of artificial nest structures. Currently, Iowa's resident goose population is stable and nests in a variety of habitats. We analyzed the effects of available habitat on nest survival and how nest survival rates compared with those of the expanding goose population studied previously to better understand how to maintain a sustainable Canada goose population in Iowa. We documented Canada goose nest survival at rural wetland sites in north-central Iowa. We monitored 121 nests in 2013 and 149 nests in 2014 at 5 Wildlife Management Areas (WMAs) with various nesting habitats, including islands, muskrat (Ondatra zibethicus) houses, and elevated nest structures. We estimated daily nest-survival rate using the nest survival model in Program MARK. Survival was influenced by year, site, stage, presence of a camera, nest age, and an interaction between nest age and stage. Nest success rates for the 28-day incubation period by site and year combination ranged from 0.10 to 0.84. Nest survival was greatest at sites with nest structures (β = 17.34). Nest survival was negatively affected by lowered water levels at Rice Lake WMA (2013 β = −0.77, nest age β = −0.07). Timing of water-level drawdowns for shallow lake restorations may influence nest survival rates.

Nest sharing under semi-natural conditions in laying hens

DEFF Research Database (Denmark)

Riber, Anja Brinch

2012-01-01

problems to laying hens, and egg production may also be negatively affected. Understanding what causes this difference in nest location selection may provide solutions to the problems associated with simultaneous nest sharing. The aims were to investigate whether a commercial strain of laying hens normally...... daily of each nest with regard to number of eggs, position, and materials used. On five mornings nesting behaviour was observed. Nest sharing occurred on all but the first 5 days of egg-laying. The majority of hens (n = 14) chose to visit an occupied nest at least once, but no hens exclusively used...

Emperor penguins nesting on Inaccessible Island

Science.gov (United States)

Jonkel, G.M.; Llano, G.A.

1975-01-01

Emperor penguins were observed nesting on Inaccessible I. during the 1973 winter. This is the southernmost nesting of emperor penguins thus far recorded; it also could be the first record of emperors attempting to start a new rookery. This site, however, may have been used by emperors in the past. The closest reported nesting of these penguins to Inaccessible I. is on the Ross Ice Shelf east of Cape Crozier. With the exception of the Inaccessible I. record, there is little evidence that emperor penguins breed in McMurdo Sound proper.

Risk from cattle trampling to nests of an endangered passerine evaluated using artificial nest experiments and simulations

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Brian W. Rolek

2016-06-01

Full Text Available Grasslands are often grazed by cattle and many grassland birds nest on the ground, potentially exposing nests to trampling. We tested for trampling risk introduced by cattle to nests of endangered Florida Grasshopper Sparrows (Ammodramus savannarum floridanus using experimentally paired grids of artificial nests (i.e., clay targets similar in size to nests of Florida Grasshopper Sparrows and counted the number of clay targets that were broken in paired grazed and ungrazed enclosures. Clay targets in grazed grids were trampled 3.9% more often than their respective ungrazed grids, and measurements of cattle presence or density were correlated with the number of broken clay targets, suggesting that excluding cattle during breeding is an important management recommendation for the Florida Grasshopper Sparrow. Trampling rates within grazed enclosures were spatially homogeneous with respect to cattle infrastructure such as supplemental feeding troughs and fences, and forests and stocking density were poor predictors of trampling rates when excluding ungrazed grids. We used population viability analysis to compare quasi-extinction rates, intrinsic growth rates, and median abundance in grazed and ungrazed Florida Grasshopper Sparrow aggregations to further understand the biological significance of management aimed at reducing trampling rates during the breeding season. Simulations indicated that trampling from grazing increased quasi-extinction rates by 41% while reducing intrinsic growth rates by 0.048, and reducing median abundance by an average of 214 singing males after 50 years. Management should avoid grazing enclosures occupied by Florida Grasshopper Sparrows during the nesting season to minimize trampling rates. Our methods that combine trampling experiments with population viability analysis provide a framework for testing effects from trampling on other grassland ground-nesting birds, and can directly inform conservation and management of the

The reasons for the different nest shapes of Megapis bees

Directory of Open Access Journals (Sweden)

Woyke Jerzy

2016-06-01

Full Text Available Over a 37-year period, we observed 1011 active bee nests and abandoned combs of Apis dorsata and Apis laboriosa in Nepal, India, the Philippines, and Bhutan. This article focuses on the reasons for the different shapes of the nests. We discovered that differing ambient conditions were the reasons for the following three shapes of symmetrical nests: vertical semi-ellipse, semicircle, and the horizontal semi-ellipse. We noted that asymmetrical nests were constructed when there was lack of space to extend the comb equally in both external directions. An asymmetrical nest also appeared when remnants of a previous comb remained on one edge of the nest. Convex nests were constructed to avoid excess sun exposure. Concave nests appeared as a result of low temperatures during the night and part of the day (Nepal. An L-shape nest was constructed when there was lack of space available to extend the nest in a straight direction. The shape of the nests also determines the way the combs fall.

Comparative evaluation of uniplex, nested, semi-nested, multiplex and nested multiplex PCR methods in the identification of microbial etiology of clinically suspected infectious endophthalmitis.

Science.gov (United States)

Bharathi, Madasamy Jayahar; Murugan, Nandagopal; Rameshkumar, Gunasekaran; Ramakrishnan, Rengappa; Venugopal Reddy, Yerahaia Chinna; Shivkumar, Chandrasekar; Ramesh, Srinivasan

2013-05-01

This study is aimed to determine the utility of various polymerase chain reaction (PCR) methods in vitreous fluids (VFs) for detecting the infectious genomes in the diagnosis of infectious endophthalmitis in terms of sensitivity and specificity. This prospective and consecutive analysis included a total of 66 VFs that were submitted for the microbiological evaluation, which were obtained from 66 clinically diagnosed endophthalmitis patients presented between November 2010 and October 2011 at the tertiary eye care referral centre in South India. Part of the collected VFs were subjected to cultures and smears, and the remaining parts were utilized for five PCR methods: uniplex, nested, semi-nested, multiplex and nested multiplex after extracting DNA, using universal eubacterial and Propionibacterium acnes species-specific primer sets targeting 16S rRNA gene in all bacteria and P. acnes, and panfungal primers, targeting 28S rRNA gene in all fungi. Of the 66 VFs, five (7.5%) showed positive results in smears, 16 (24%) in cultures and 43 (65%) showed positive results in PCRs. Among the 43 positively amplified VFs, 10 (15%) were positive for P. acnes genome, one for panfungal genome and 42 (62%) for eubacterial genome (including 10 P. acnes positives). Among 42 eubacterial-positive VFs, 36 were positive by both uniplex (first round) and multiplex (first round) PCRs, while nested (second round) and nested multiplex (second round) PCRs produced positive results in 42 and 41 VFs, respectively. Of the 43 PCR-positive specimens, 16 (37%) had positive growth (15 bacterial and one fungal) in culture. Of 50 culture-negative specimens, 27 (54%) were showed positive amplification, of which 10 were amplified for both P. acnes and eubacterial genomes and the remaining 17 were for eubacterial genome alone. Nested PCRs are superior than uniplex and multiplex PCR. PCRs proved to be a powerful tool in the diagnosis of endophthalmitis, especially for detecting uncultured microbes.

Variation in clutch size in relation to nest size in birds.

Science.gov (United States)

Møller, Anders P; Adriaensen, Frank; Artemyev, Alexandr; Bańbura, Jerzy; Barba, Emilio; Biard, Clotilde; Blondel, Jacques; Bouslama, Zihad; Bouvier, Jean-Charles; Camprodon, Jordi; Cecere, Francesco; Charmantier, Anne; Charter, Motti; Cichoń, Mariusz; Cusimano, Camillo; Czeszczewik, Dorota; Demeyrier, Virginie; Doligez, Blandine; Doutrelant, Claire; Dubiec, Anna; Eens, Marcel; Eeva, Tapio; Faivre, Bruno; Ferns, Peter N; Forsman, Jukka T; García-Del-Rey, Eduardo; Goldshtein, Aya; Goodenough, Anne E; Gosler, Andrew G; Góźdź, Iga; Grégoire, Arnaud; Gustafsson, Lars; Hartley, Ian R; Heeb, Philipp; Hinsley, Shelley A; Isenmann, Paul; Jacob, Staffan; Järvinen, Antero; Juškaitis, Rimvydas; Korpimäki, Erkki; Krams, Indrikis; Laaksonen, Toni; Leclercq, Bernard; Lehikoinen, Esa; Loukola, Olli; Lundberg, Arne; Mainwaring, Mark C; Mänd, Raivo; Massa, Bruno; Mazgajski, Tomasz D; Merino, Santiago; Mitrus, Cezary; Mönkkönen, Mikko; Morales-Fernaz, Judith; Morin, Xavier; Nager, Ruedi G; Nilsson, Jan-Åke; Nilsson, Sven G; Norte, Ana C; Orell, Markku; Perret, Philippe; Pimentel, Carla S; Pinxten, Rianne; Priedniece, Ilze; Quidoz, Marie-Claude; Remeš, Vladimir; Richner, Heinz; Robles, Hugo; Rytkönen, Seppo; Senar, Juan Carlos; Seppänen, Janne T; da Silva, Luís P; Slagsvold, Tore; Solonen, Tapio; Sorace, Alberto; Stenning, Martyn J; Török, János; Tryjanowski, Piotr; van Noordwijk, Arie J; von Numers, Mikael; Walankiewicz, Wiesław; Lambrechts, Marcel M

2014-09-01

Nests are structures built to support and protect eggs and/or offspring from predators, parasites, and adverse weather conditions. Nests are mainly constructed prior to egg laying, meaning that parent birds must make decisions about nest site choice and nest building behavior before the start of egg-laying. Parent birds should be selected to choose nest sites and to build optimally sized nests, yet our current understanding of clutch size-nest size relationships is limited to small-scale studies performed over short time periods. Here, we quantified the relationship between clutch size and nest size, using an exhaustive database of 116 slope estimates based on 17,472 nests of 21 species of hole and non-hole-nesting birds. There was a significant, positive relationship between clutch size and the base area of the nest box or the nest, and this relationship did not differ significantly between open nesting and hole-nesting species. The slope of the relationship showed significant intraspecific and interspecific heterogeneity among four species of secondary hole-nesting species, but also among all 116 slope estimates. The estimated relationship between clutch size and nest box base area in study sites with more than a single size of nest box was not significantly different from the relationship using studies with only a single size of nest box. The slope of the relationship between clutch size and nest base area in different species of birds was significantly negatively related to minimum base area, and less so to maximum base area in a given study. These findings are consistent with the hypothesis that bird species have a general reaction norm reflecting the relationship between nest size and clutch size. Further, they suggest that scientists may influence the clutch size decisions of hole-nesting birds through the provisioning of nest boxes of varying sizes.

Nest site selection by Hypsiboas faber(Anura, Hylidae in Southern Brazil

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André L. Luza

2015-12-01

Full Text Available ABSTRACT Male gladiator frogs of Hypsiboas Wagler, 1830 build nests on available substrate surrounding ponds and streams where female spawn eggs during the breeding period. Although gladiator frogs seem to show plasticity in the way they construct their nests, there is no study reporting if these species present preferences about microhabitat conditions for nest-building (mainly under subtropical climate. Predation pressure and environmental conditions have been considered major processes shaping the great diversity of reproductive strategies performed by amphibians, but microhabitat conditions should explain where to build a nest as well as how nest looks. This study aimed to test nest site selection for nest-building by Hypsiboas faber(Wied-Neuwied, 1821, determining which factors are related to nest site selection and nest features. The survey was conducted at margins of two permanent ponds in Southern Brazil. Habitat factors were evaluated in 18 plots with nest and 18 plots in the surrounding without nest (control, describing vegetation structure and heterogeneity, and substrate characteristics. Water temperature was measured inside the nest and in its adjacency. Nest features assessed were area, depth and temperature. Habitat characteristics differed between plots with and without nest. Microhabitat selected for nest-building was characterized by great vegetation cover and height, as well as shallower water and lower cover of organic matter in suspension than in plots without nest. Differences between temperature inside nest and in its adjacency were not observed. No relationship between nest features and habitat descriptors was evidenced. Results revealed that Hypsiboas faber does not build nests anywhere. Males seem to prefer more protected habitats, probably avoiding predation, invasion of conspecific males and inclement weather. Lack of differences between temperature inside- and outside-nest suggest that nest do not improve this

Sobre el carácter selectivo de las pruebas de acceso a la Universidad

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MANUEL JUSTEL

1981-01-01

Full Text Available Se afirma el carácter clasista de la universidad española. Se analizan las pruebas de acceso a la universidad para determinar el papel que juegan en el reclutamiento de estudiantes. También se examina la composición social de los estudiantes. Los datos resultantes muestran que los hijos de padres de clases sociales más altas suponen el 31,9% de los estudiantes, aunque sus padres representen sólo el 3,3% de la población general. Igualmente, los hijos de padres de clase media (4,1% de la población constituyen el 14,6% de los estudiantes. Se concluye afirmando que las pruebas de selectividad no tienen un carácter marcadamente clasista, sino que refuerzan simbólicamente una selección efectuada en los niveles anteriores del sistema educativo. Es en las enseñanzas primaria y media donde actúan con más fuerza los filtros selectivos que discriminan a los estudiantes de origen social modesto. En este sentido, es muy marcada la influencia negativa que ejerce el entorno rural para el acceso de los estudiantes a la universidad, ya que son gente con menor nivel de renta, menor nivel cultural de los padres e inferior estímulo académico de la familia y el entorno.

Evaluación de la prueba de inmunofluorescencia indirecta para el diagnóstico de leptospirosis humana.

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Piedad Agudelo Flórez

2006-06-01

Full Text Available Introducción. El diagnóstico de la leptospirosis es difícil debido al amplio espectro de síntomas clínicos que presenta. Varias pruebas diagnósticas serológicas se han desarrollado, pero su aplicación y utilidad en Colombia no han sido determinadas. Objetivos. Evaluar la prueba de inmunofluorescencia indirecta para el diagnóstico de leptospirosis humana y determinar así los anticuerpos de las clases inmunoglobulina G y M producidos contra Leptospira. Materiales y métodos. Se establecieron tres grupos de estudio. El primero incluyó 19 muestras positivas para leptospirosis de pacientes con diagnóstico clínico y prueba de microaglutinación positiva; el segundo, 40 muestras de personas sin antecedentes de leptospirosis y con microaglutinación negativa, y el tercero con 96 muestras de pacientes con otras enfermedades diferentes a leptospirosis. Todas las muestras fueron procesadas por inmunofluorescencia indirecta. Resultados. Se determinó que la inmunofluorescencia indirecta tiene sensibilidad de 89,47%, especificidad de 100%, valor predictivo negativo de 95,2% (IC95%82,6 a 99,2 y valor predictivo positivo de 100%. En forma paralela, un estudio exploratorio en 27 muestras de suero que habían sido remitidas para diagnóstico de diferentes síndromes febriles encontró que 11% de ellas fueron positivas por inmunofluorescencia indirecta para anticuerpos IgM contra Leptospira. Conclusiones. La inmunofluorescencia indirecta es una alternativa que complementa el diagnóstico de leptospirosis y los estudios seroepidemiológicos. La presencia de anticuerpos dirigidos contra Leptospira en las muestras de síndrome febril del estudio indica que la leptospirosis es una de las causas de este síndrome que el clínico debe explorar.

Accionamiento de un ventilador industrial para prueba de aerogeneradores; Drive of an industrial fan for wind testing

Directory of Open Access Journals (Sweden)

Francisco Eneldo López Monteagudo

2015-04-01

Full Text Available En este trabajo se implementó el control de un ventilador industrial utilizado para prueba de aerogeneradores, el cual es empleado como un dispositivo interno en la elaboración de un túnel de viento, para realizar pruebas de medición de viento. El proyecto consistió en regular la velocidad de un ventilador industrial utilizado en un túnel de viento, para realizar pruebas de sistemas de control en aerogeneradores, generándose señales de viento reguladas en valores constantes, ó que sigan un perfil definido por una base de datos de valores reales medidos con un anemómetro. Para implementar el sistema de control y la comunicación de los dispositivos, se empleó un procesador digital de señales (PDS de Texas Instruments EZDSP2407, que actúa como interfaz para transmitir los datos entre el entorno de programación (VisSim Embedded Control Developer (ECD. Además se utilizó un variador de velocidad de 3HP de la marca SIEMENS modelo Micromaster 420. In this work, a fan control industrial wind turbines used for test, which is used as an internal device in the development of a wind tunnel for testing wind measurement. The project consists of regulating the speed of an industrial fan used in a wind tunnel to test control systems in wind turbines, wind generating regulated signals in constant, or to follow a profile defined by a database of values actual measured with an anemometer. To implement the control system and communication devices, in this project employed a digital signal processor (DSP from Texas Instruments EZDSP2407, which acts as an interface to transmit data between the programming environments (VisSim Embedded Control Developer (ECD. Also uses a variable speed 3HP SIEMENS Micromaster model 420.

Factors affecting nesting success in the Great-crested Grebe ...

African Journals Online (AJOL)

The overall nesting success was 70.4% (N = 209), with nest failure caused mainly by predation (65%) and flooding (23%). Breeding outcome was significantly and positively related to nest size, with bigger nests conferring better survival to eggs and young probably through affording better protection during spells of adverse ...

Nesting ecology and nest success of the Blue Grosbeak along two rivers in New Mexico

Science.gov (United States)

Jean-Luc E. Cartron; Deborah M. Finch; David L. Hawksworth; Scott H. Stoleson

2013-01-01

From 1997 through 2008, we studied the nesting habits and nest success of the Blue Grosbeak (Passerina cerulean) along the middle Gila River (1997-2001) and the middle Rio Grande (2000-2008) in New Mexico. A riparian forest of cottonwoods grows along both rivers. but the forest along the Rio Grande is a much more intensively managed ecosystem, with an understory...

Prueba de campo específica de valoración de la resistencia en tenis: respuesta cardiaca y efectividad técnica en jugadores de competición

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Ernest Baiget

2008-09-01

Full Text Available Aunque la resistencia específica del jugador tiene una influencia directa sobre el rendimiento en el tenis, un deporte intermitente de larga duración, las pruebas utilizadas para valorarla no suelen incluir tareas motrices próximas a situaciones de juego reales y pueden ser consideradas de baja especificidad. El objetivo de este estudio es desarrollar una prueba de campo de valoración de la resistencia específica en tenis (Specific Endurance Tennis Test, SET-Test, analizando el comportamiento de la frecuencia cardiaca (FC y de parámetros de efectividad técnica (ET, con el fin de averiguar una posible relación entre ambos parámetros y de éstos con el rendimiento deportivo en jugadores de competición. Participaron siete tenistas masculinos, a los cuales les fue administrada una prueba triangular, progresiva, continua y de intensidad máxima conducida por una máquina lanzapelotas, durante la cual se registró la FC y, al mismo tiempo, parámetros objetivos de ET (precisión y potencia mediante el cálculo de porcentaje de aciertos y errores. Se observa un punto de deflexión de la FC (PDFC en un 86% de los sujetos estudiados, previo o coincidente con una disminución de la ET (punto de deflexión de la eficiencia técnica, PDET. Estos dos puntos analizados de forma simultánea a lo largo de la prueba se muestran relacionados con el rendimiento competitivo de los jugadores estudiados. Se concluye que la prueba propuesta puede ser un método específico y válido para evaluar la resistencia específica y la condición aeróbica en tenistas, aunque son necesarios más estudios con el fin de confirmar las hipótesis planteadas y la validez externa de la prueba.

Facultative nest patch shifts in response to nest predation risk in the Brewer's sparrow: a "win-stay, lose-switch" strategy?

Science.gov (United States)

Anna D. Chalfoun; Thomas E. Martin

2010-01-01

Facultative shifts in nesting habitat selection in response to perceived predation risk may allow animals to increase the survival probability of sessile offspring. Previous studies on this behavioral strategy have primarily focused on single attributes, such as the distance moved or changes in nesting substrate. However, nest site choice often encompasses multiple...

Language Nests and Language Acquisition: An Empirical Analysis

Science.gov (United States)

Okura, Eve K.

2017-01-01

This dissertation presents the findings from interviews conducted with language nest workers, teachers, language nest coordinators, administrators of language revitalization programs, principals and directors of language immersion schools that work in close proximity with language nests, and linguists involved in language revitalization efforts.…

Intradermo-reaccion en la Leishmaniosis Tegumentaria en el Perú: La prueba intradérmica con "leishmanina" en perros y conejos

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German Battistini M

1945-06-01

Full Text Available Se ha probado el antígeno "leishmanina" en conejos inmunizados y perros inoculados con cultivos de Leishmania brasiliensis procedentes de casos de uta, obteniendo los siguientes resultados : 1. En los conejos la prueba intradérmica ha sido manifiesta entre las 24 y 48 horas, hasta con diluciones al 1/10 del antígeno. 2. Usando el antígeno sin diluír, en los perros también se obtuvo resultados positivos comparables a los obtenidos en los conejos, pero sólo durante los 20 días siguientes a la inoculación (con cultivos de leishmania. Una prueba llevada a cabo 10 días después, fué negativa.

LA MEMORIA Y EL LENGUAJE EN PRUEBAS TESTIFICALES CON MENORES DE 3 A 6 AÑOS

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Eva A. Silva

2016-09-01

Full Text Available La prueba testifical de menores de corta edad es, en muchos casos, la principal y única prueba indiciaria en los procesos penales. La memoria y el lenguaje son dos de los principales componentes en la declaración del menor que requieren un especial análisis, no sólo por el importante papel que juegan, sino también por la relación existente entre ambas capacidades. La vulnerabilidad de la memoria y su posibilidad de ser alterada mediante sugerencias, así como la variabilidad del desarrollo del lenguaje en el menor de 3 a 6 años edad, son dos factores de influencia en la recogida del testimonio. Estos factores, junto con la pericia del entrevistador en la adaptación de la entrevista al menor al que va dirigida podrán conseguir una recogida de información fiable y libre de subjetividades que facilitarán la investigación de los hechos denunciados. El presente artículo presenta una visión conjunta de ambas capacidades desde la perspectiva del testimonio infantil en el proceso penal.

Nest mortality of sagebrush songbirds due to a severe hailstorm

Science.gov (United States)

Hightower, Jessica N.; Carlisle, Jason D.; Chalfoun, Anna D.

2018-01-01

Demographic assessments of nesting birds typically focus on failures due to nest predation or brood parasitism. Extreme weather events such as hailstorms, however, can also destroy eggs and injure or kill juvenile and adult birds at the nest. We documented the effects of a severe hailstorm on 3 species of sagebrush-associated songbirds: Sage Thrasher (Oreoscoptes montanus), Brewer's Sparrow (Spizella breweri), and Vesper Sparrow (Pooecetes gramineus), nesting at eight 24 ha study plots in central Wyoming, USA. Across all plots, 17% of 128 nests failed due to the hailstorm; however, all failed nests were located at a subset of study plots (n = 3) where the hailstorm was most intense, and 45% of all nests failures on those plots were due to hail. Mortality rates varied by species, nest architecture, and nest placement. Nests with more robust architecture and those sited more deeply under the shrub canopy were more likely to survive the hailstorm, suggesting that natural history traits may modulate mortality risk due to hailstorms. While sporadic in nature, hailstorms may represent a significant source of nest failure to songbirds in certain locations, especially with increasing storm frequency and severity forecasted in some regions with ongoing climate change.

Determinants of abundance and effects of blood-sucking flying insects in the nest of a hole-nesting bird.

Science.gov (United States)

Tomás, Gustavo; Merino, Santiago; Martínez-de la Puente, Josué; Moreno, Juan; Morales, Judith; Lobato, Elisa

2008-05-01

Compared to non-flying nest-dwelling ectoparasites, the biology of most species of flying ectoparasites and its potential impact on avian hosts is poorly known and rarely, if ever, reported. In this study we explore for the first time the factors that may affect biting midge (Diptera: Ceratopogonidae) and black fly (Diptera: Simuliidae) abundances in the nest cavity of a bird, the hole-nesting blue tit Cyanistes caeruleus, and report their effects on adults and nestlings during reproduction. The abundance of biting midges was positively associated with nest mass, parental provisioning effort and abundance of blowflies and black flies, while negatively associated with nestling condition. Furthermore, a medication treatment to reduce blood parasitaemias in adult birds revealed that biting midges were more abundant in nests of females whose blood parasitaemias were experimentally reduced. This finding would be in accordance with these insect vectors attacking preferentially uninfected or less infected hosts to increase their own survival. The abundance of black flies in the population was lower than that of biting midges and increased in nests with later hatching dates. No significant effect of black fly abundance on adult or nestling condition was detected. Blood-sucking flying insects may impose specific, particular selection pressures on their hosts and more research is needed to better understand these host-parasite associations.

Nesting behavior of Palila, as assessed from video recordings

Science.gov (United States)

Laut, M.E.; Banko, P.C.; Gray, E.M.

2003-01-01

We quantified nesting behavior of Palila (Loxiodes bailleui), an endangered Hawaiian honeycreeper, by recording at nests during three breeding seasons using a black-and-white video camera connected to a Videocassette recorder. A total of seven nests was observed. We measured the following factors for daylight hours: percentage of time the female was on the nest (attendance), length of attendance bouts by the female, length of nest recesses, and adult provisioning rates. Comparisons were made between three stages of the 40-day nesting cycle: incubation (day 1-day 16), early nestling stage (day 17-day 30 [i.e., nestlings ??? 14 days old]), and late nestling stage (day 31-day 40 [i.e., nestlings > 14 days old]). Of seven nests observed, four fledged at least one nestling and three failed. One of these failed nests was filmed being depredated by a feral cat (Felis catus). Female nest attendance was near 82% during the incubation stage and decreased to 21% as nestlings aged. We did not detect a difference in attendance bout length between stages of the nesting cycle. Mean length of nest recesses increased from 4.5 min during the incubation stage to over 45 min during the late nestling stage. Mean number of nest recesses per hour ranged from 1.6 to 2.0. Food was delivered to nestlings by adults an average of 1.8 times per hour for the early nestling stage and 1.5 times per hour during the late nestling stage and did not change over time. Characterization of parental behavior by video had similarities to but also key differences from findings taken from blind observations. Results from this study will facilitate greater understanding of Palila reproductive strategies.

A review of the nest protection hypothesis: does inclusion of fresh green plant material in birds' nests reduce parasite infestation?

Science.gov (United States)

Scott-Baumann, James F; Morgan, Eric R

2015-07-01

The use of aromatic plants and their essential oils for ectoparasite treatment is a field of growing interest. Several species of birds regularly introduce aromatic herbs into their nests putatively to reduce parasites. The behaviour is most often seen in cavity nesting birds and after nest building has finished. The plants are included in a non-structural manner and are often strongly aromatic. Various different hypotheses have been proposed regarding the function of this behaviour; from the plants altering some non-living factor in the nest (crypsis, water loss and insulation hypotheses) to them being involved in mate selection (mate hypothesis) or even having a beneficial effect, direct or indirect, on chicks (drug or nest protection hypothesis, NPH). Many studies have been carried out over the years observing and experimentally testing these hypotheses. This review focuses on studies involving the most popular of these hypotheses, the NPH: that plants decrease nest parasites or pathogens, thereby conveying positive effects to the chicks, allowing the behaviour to evolve. Studies providing observational evidence towards this hypothesis and those experimentally testing it are discussed.

Effectiveness of nest site restoration for the endangered northern map turtle : report 2 : use of artificial nesting sites and wildlife exclusion fences to enhance nesting success : research summary.

Science.gov (United States)

2016-10-01

The Northern Map Turtle, is a state Endangered Species, found only in the : lower Susquehanna River in Maryland. The only area where nests of this : species are not heavily impacted by predators is in the town of Port Deposit. : However, turtles nest...

Effects of intraguild predators on nest-site selection by prey.

Science.gov (United States)

Huang, Wen-San; Pike, David A

2012-01-01

Nest-site selection involves tradeoffs between the risk of predation (on females and/or nests) and nest-site quality (microenvironment), and consequently suitable nesting sites are often in limited supply. Interactions with "classical" predators (e.g., those not competing for shared resources) can strongly influence nest-site selection, but whether intraguild predation also influences this behavior is unknown. We tested whether risk of predation from an intraguild predator [the diurnal scincid lizard Eutropis (Mabuya) longicaudata] influences nest-site selection by its prey (the nocturnal gecko Gekko hokouensis) on Orchid Island, Taiwan. These two species putatively compete for shared resources, including invertebrate prey and nesting microhabitat, but the larger E. longicaudata also predates G. hokouensis (but not its hard-shelled eggs). Both species nested within a concrete wall containing a series of drainage holes that have either one ("closed-in") or two openings ("open"). In allopatry, E. longicaudata preferred to nest within holes that were plugged by debris (thereby protecting eggs from water intrusion), whereas G. hokouensis selected holes that were open at both ends (facilitating escape from predators). When we experimentally excluded E. longicaudata from its preferred nesting area, G. hokouensis not only nested in higher abundances, but also modified its nest-site selection, such that communal nesting was more prevalent and both open and closed-in holes were used equally. Egg viability was unaffected by the choice of hole type, but was reduced slightly (by 7%) in the predator exclusion area (presumably due to higher local incubation temperatures). Our field experiment demonstrates that intraguild predators can directly influence the nest density of prey by altering maternal nest-site selection behavior, even when the predator and prey are active at different times of day and the eggs are not at risk of predation.

Observations of sea turtles nesting on Misali islan, Pemba | Pharoah ...

African Journals Online (AJOL)

A nest-recording programme has collected data over five years from turtles nesting on Misali Island, off the West coast of Pemba, Tanzania. Five species of sea turtle are known to occur in Zanzibar waters, two of these species nested regularly on the island, with green turtle nests outnumbering hawksbill turtle nests by a ...

Aplicación de dos pruebas estadísticas de bondad de ajuste en muestras complejas: un caso práctico en el campo forestal

OpenAIRE

Quintero-Méndez, María A.; Durán-Núñez, Mariano J.

2008-01-01

En esta investigación se comparan dos pruebas de bondad de ajuste en términos de su error tipo I: ji-cuadrada de Pearson y Rao-Scott con corrección de segundo orden, aplicadas a datos recolectados mediante técnicas de muestreo que no cumplen los supuestos de independencia e igual probabilidad de inclusión de las observaciones, llamadas muestras complejas. Ambas pruebas se usaron para ajustar categorías diamétricas en una plantación de gmelina (Gmelina arborea), aplicando muestreo sistemático ...

Is it safe to nest near conspicuous neighbours? Spatial patterns in predation risk associated with the density of American Golden-Plover nests

OpenAIRE

Marie-Andrée Giroux; Myriam Trottier-Paquet; Joël Bêty; Vincent Lamarre; Nicolas Lecomte

2016-01-01

Predation is one of the main factors explaining nesting mortality in most bird species. Birds can avoid nest predation or reduce predation pressure by breeding at higher latitude, showing anti-predator behaviour, selecting nest sites protected from predators, and nesting in association with protective species. American Golden-Plovers (Pluvialis dominica) defend their territory by using various warning and distraction behaviours displayed at varying levels of intensity (hereafter ?conspicuous ...

Efficient processing of containment queries on nested sets

NARCIS (Netherlands)

Ibrahim, A.; Fletcher, G.H.L.

2013-01-01

We study the problem of computing containment queries on sets which can have both atomic and set-valued objects as elements, i.e., nested sets. Containment is a fundamental query pattern with many basic applications. Our study of nested set containment is motivated by the ubiquity of nested data in

Conservation implications when the nest predators are known

Science.gov (United States)

Ribic, Christine; Thompson, Frank

2012-01-01

Conservation and management of passerines has largely focused on habitat manipulation or restoration because the natural communities on which these birds depend have been destroyed and fragmented. However, productivity is another important aspect of avian conservation, and nest predation can be a large source of nesting mortality for passerines. Recent studies using video surveillance to identify nest predators allow researchers to start evaluating what methods could be used to mitigate nest predation to help passerines of conservation concern. From recent studies, we identified latitudinal and habitat-related patterns in the importance of predator groups that depredate passerine nests. We then reviewed how knowledge of specific nest predators can benefit conservation of bird species of concern. Mammals were the dominant predator group in northern grasslands. Snakes were the dominant predator group in southern habitats. Fire ants were only a nest predator in southern latitudes. Differences in the importance of predator species or groups were likely the result of both their geographic patterns of distribution and habitat preferences. Some direct and indirect predator control measures developed for waterfowl management potentially could be used to benefit passerine productivity. We reviewed three examples-cowbirds, snakes in shrublands, and ground squirrels in grasslands-to illustrate how different predator control strategies may be needed in different situations. Mitigation of passerine nest predation will need to be based on knowledge of predator communities to be effective. This requires large samples of predation events with identified predators; video technology is essential for this task.

Landscape-moderated bird nest predation in hedges and forest edges

Science.gov (United States)

Ludwig, Martin; Schlinkert, Hella; Holzschuh, Andrea; Fischer, Christina; Scherber, Christoph; Trnka, Alfréd; Tscharntke, Teja; Batáry, Péter

2012-11-01

Landscape-scale agricultural intensification has caused severe declines in biodiversity. Hedges and forest remnants may mitigate biodiversity loss by enhancing landscape heterogeneity and providing habitat to a wide range of species, including birds. However, nest predation, the major cause of reproductive failure of birds, has been shown to be higher in forest edges than in forest interiors. Little is known about how spatial arrangement (configuration) of hedges affects the avian nest predation. We performed an experiment with artificial ground and elevated nests (resembling yellowhammer and whitethroat nests) baited with quail and plasticine eggs. Nests were placed in three habitat types with different degrees of isolation from forests: forest edges, hedges connected to forests and hedges isolated from forests. Nest predation was highest in forest edges, lowest in hedges connected to forests and intermediate in isolated hedges. In the early breeding season, we found similar nest predation on ground and elevated nests, but in the late breeding season nest predation was higher on ground nests than on elevated nests. Small mammals were the main predators of ground nests and appeared to be responsible for the increase in predation from early to late breeding season, whereas the elevated nests were mainly depredated by small birds and small mammals. High predation pressure at forest edges was probably caused by both forest and open-landscape predators. The influence of forest predators may be lower at hedges, leading to lower predation pressure than in forest edges. Higher predation pressure in isolated than connected hedges might be an effect of concentration of predators in these isolated habitats. We conclude that landscape configuration of hedges is important in nest predation, with connected hedges allowing higher survival than isolated hedges and forest edges.

Timing, Nest Site Selection and Multiple Breeding in House Martins: Age-Related Variation and the Preference for Self-Built Mud Nests

NARCIS (Netherlands)

Piersma, T.

2013-01-01

Almost all accounts of the reproductive biology of House Martins Delichon urbicum are based on studies of birds breeding in artificial nests that are monitored every few days. Here, I provide a study on House Martins using self-built mud nests at a single colony in Gaast, The Netherlands (225 nest

Timing, nest site selection and multiple breeding in House Martins : age-related variation and the preference for self-built mud nests

NARCIS (Netherlands)

Piersma, Theunis

2013-01-01

Almost all accounts of the reproductive biology of House Martins Delichon urbicum are based on studies of birds breeding in artificial nests that are monitored every few days. Here, I provide a study on House Martins using self-built mud nests at a single colony in Gaast, The Netherlands (225 nest

Does cooperation mean kinship between spatially discrete ant nests?

Science.gov (United States)

Procter, Duncan S; Cottrell, Joan E; Watts, Kevin; A'Hara, Stuart W; Hofreiter, Michael; Robinson, Elva J H

2016-12-01

Eusociality is one of the most complex forms of social organization, characterized by cooperative and reproductive units termed colonies. Altruistic behavior of workers within colonies is explained by inclusive fitness, with indirect fitness benefits accrued by helping kin. Members of a social insect colony are expected to be more closely related to one another than they are to other conspecifics. In many social insects, the colony can extend to multiple socially connected but spatially separate nests (polydomy). Social connections, such as trails between nests, promote cooperation and resource exchange, and we predict that workers from socially connected nests will have higher internest relatedness than those from socially unconnected, and noncooperating, nests. We measure social connections, resource exchange, and internest genetic relatedness in the polydomous wood ant Formica lugubris to test whether (1) socially connected but spatially separate nests cooperate, and (2) high internest relatedness is the underlying driver of this cooperation. Our results show that socially connected nests exhibit movement of workers and resources, which suggests they do cooperate, whereas unconnected nests do not. However, we find no difference in internest genetic relatedness between socially connected and unconnected nest pairs, both show high kinship. Our results suggest that neighboring pairs of connected nests show a social and cooperative distinction, but no genetic distinction. We hypothesize that the loss of a social connection may initiate ecological divergence within colonies. Genetic divergence between neighboring nests may build up only later, as a consequence rather than a cause of colony separation.

The Role of Non-Foraging Nests in Polydomous Wood Ant Colonies.

Science.gov (United States)

Ellis, Samuel; Robinson, Elva J H

2015-01-01

A colony of red wood ants can inhabit more than one spatially separated nest, in a strategy called polydomy. Some nests within these polydomous colonies have no foraging trails to aphid colonies in the canopy. In this study we identify and investigate the possible roles of non-foraging nests in polydomous colonies of the wood ant Formica lugubris. To investigate the role of non-foraging nests we: (i) monitored colonies for three years; (ii) observed the resources being transported between non-foraging nests and the rest of the colony; (iii) measured the amount of extra-nest activity around non-foraging and foraging nests. We used these datasets to investigate the extent to which non-foraging nests within polydomous colonies are acting as: part of the colony expansion process; hunting and scavenging specialists; brood-development specialists; seasonal foragers; or a selfish strategy exploiting the foraging effort of the rest of the colony. We found that, rather than having a specialised role, non-foraging nests are part of the process of colony expansion. Polydomous colonies expand by founding new nests in the area surrounding the existing nests. Nests founded near food begin foraging and become part of the colony; other nests are not founded near food sources and do not initially forage. Some of these non-foraging nests eventually begin foraging; others do not and are abandoned. This is a method of colony growth not available to colonies inhabiting a single nest, and may be an important advantage of the polydomous nesting strategy, allowing the colony to expand into profitable areas.

Some problems of the origin of galaxy nests

International Nuclear Information System (INIS)

Metlov, V.G.

1979-01-01

The origin of galaxy nests have been studied. The nests of galaxies consist of a few (more than two) galaxies in contact with each other and strongly distorted by mutual interaction. Their colour, geometrical and morphological characteristics are compared with ones of ordinary galaxies and groups of galaxies. Conclusions are drawn that 5% to 15% of the total number of nests may be the evolutionary products of tight groups of galaxies (with diameter 11 Msub(Sun)). About half of such objects consist of elliptical galaxies. Galaxies in sufficiently tight groups may merge in consequence of dynamical friction. The remaining (85-95%) nests origin may be possibly explained by different kinds of instabilities in certain flat galaxies, with transformation of one galaxy to the nest, or by interaction of two galaxies containing large amounts of gas and consequent intensive star formation in very large regions, or by other causes. To establish relative contribution of each possible phenomenon in nests origin, it is required to carry out further detailed investigations of these objects

No evidence for UV-based nest-site selection in sticklebacks

Directory of Open Access Journals (Sweden)

Bakker Theo CM

2006-11-01

Full Text Available Abstract Background Nests are built in various animal taxa including fish. In systems with exclusive male parental care, the choice of a nest site may be an important component of male fitness. The nest site may influence male attractiveness as a mate, and male, embryo, and juvenile survival probabilities. Reproductively active three-spined stickleback males establish and defend a territory in which they build a nest. Territories can differ remarkably in qualities that influence male and female reproductive success like predation risk or abiotic factors such as dissolved oxygen concentration or lighting conditions. The latter may be important because in sticklebacks the extended visual capability into the ultraviolet (UV wave range plays a role in female mate choice. Males are thus expected to be choosy about the habitat in which they will build their nest. Results We tested nest-site choice in male three-spined sticklebacks with respect to different UV lighting conditions. Reproductively active males were given the simultaneous choice to build their nest either in an UV-rich (UV+ or an UV-lacking (UV- environment. Males exhibited no significant nest-site preferences with respect to UV+ or UV-. However, larger males and also heavier ones completed their nests earlier. Conclusion We found that UV radiation as well as differences in luminance had no influence on nest-site choice in three-spined sticklebacks. Males that built in the UV-rich environment were not different in any trait (body traits and UV reflection traits from males that built in the UV-poor environment. There was a significant effect of standard length and body mass on the time elapsed until nest completion in the UV experiment. The larger and heavier a male, the faster he completed his nest. In the brightness control experiment there was a significant effect only of body mass on the duration of nest completion. Whether nest building preferences with respect to UV lighting

Variation in clutch size in relation to nest size in birds

OpenAIRE

Moller Anders P.; Adriaensen Frank; Artemyev Alexandr; Banbura Jerzy; Barba Emilio; Biard Clotilde; Blondel Jacques; Bouslama Zihad; Bouvier Jean-Charles; Camprodon Jordi; Cecere Francesco; Charmantier Anne; Charter Motti; Cichon Mariusz; Cusimano Camillo

2014-01-01

© 2014 The Authors. Nests are structures built to support and protect eggs and/or offspring from predators, parasites, and adverse weather conditions. Nests are mainly constructed prior to egg laying, meaning that parent birds must make decisions about nest site choice and nest building behavior before the start of egg-laying. Parent birds should be selected to choose nest sites and to build optimally sized nests, yet our current understanding of clutch size-nest size relationships is limited...

Estudio correlacional entre las pruebas de bachillerato en la educación media y el rendimiento en educación diversificada

Directory of Open Access Journals (Sweden)

Tania Elena Moreira Mora

2002-01-01

Full Text Available La intencionalidad de este estudio fue medir el grado de asociación entre las calificaciones obtenidas por los estudiantes en la Educación Diversificada en las cinco asignaturas medidas en el Bachillerato de Educación Media, con sus respectivos resultados en las pruebas nacionales de acreditación, con la población de estudiantes que realizaron en 1999 las pruebas de bachillerato. El estudio se realizó en la División de Control de Calidad del Ministerio Educación Pública. El análisis estadístico se centró en los porcentajes de estudiantes aprobados por cada asignatura según el sexo, la zona, la modalidad y el tipo de colegio, así como, los correspondientes coeficientes de correlación producto-momento de Pearson

Examinando exámenes. Consideraciones acerca de las pruebas de medición en ELE

Directory of Open Access Journals (Sweden)

Yagüe Barredo, Agustín

2010-02-01

Full Text Available El objetivo de este artículo es reflexionar acerca del concepto y el diseño de exámenes de español como lengua extranjera. Con criterios empíricos se subrayan las limitaciones técnicas de las pruebas y la pobreza de información que ofrecen a docentes y a candidatos sobre su actuación. El trabajo propone algunas alternativas que deben ser refrendadas en situaciones de aula.

Testing and start up of equipment in a substation; Pruebas y puesta en servicio del equipo de una subestacion

Energy Technology Data Exchange (ETDEWEB)

Raull-Martin, J. [Universidad Nacional Autonoma de Mexico, Mexico, D.F. (Mexico)

2001-09-01

The purpose of this paper is to present a summarized version of the test series required to determine out the final condition of the isolations, the continuity of the control circuits, as well as protection, measurement, sing-positing, alarms and the total substation performance. [Spanish] El proposito de este articulo es presentar en forma compacta la serie de pruebas que se requieren para determinar el estado final de los aislamientos, la continuidad de los circuitos de control, proteccion, medicion, senalizacion, alarmas, asi como el funcionamiento del conjunto de la subestacion. Se muestra una grafica K-Temperatura y de conexiones para las pruebas con megger. Se muestra un diagrama de conexiones para determinar las marcas de polaridad este tipo bushing e interruptores; asi como para el faseo de una proteccion diferencial. Se da el diagrama de faseo interno y energizado por el lado de 23 kV de una subestacion de 230 kV.

The Rufous Hornero (Furnarius rufus) nest as an incubation chamber.

Science.gov (United States)

Shibuya, Felipe L S; Braga, Talita V; Roper, James J

2015-01-01

Foraging and incubation are mutually exclusive activities for parent birds. A trade-off is generated when a combination of food availability and temperature regulation force birds to choose one and neglect the other, at least temporarily. The Rufous Hornero builds large, oven-like, mud nests, the evolutionary cause of which remains unknown. We tested that temperature variation inside the nest is that which is expected if one function of the nest were for temperate regulation. If so, this would suggest that the nest works as an incubation chamber (but which now may serve more than one function). We divided nests into two natural treatments: nests that received more continuous direct sunshine (sun), and those that received less direct sunshine, due to shade from trees or buildings (shade). Thermometer data loggers were placed in the nest cavity and outside, in the shade of the nest, and temperature was measured every 10min. We predicted that temperatures would consistently be higher and less variable in nests than outside nests. Also, at higher ambient temperatures the nest would function better as an incubation chamber as a consequence of having evolved in a hotter climate. Thus, in Curitiba, where temperatures are lower than where the species (and nest) evolved, nests in greater sunshine should have thermal characteristics that support the incubation chamber hypothesis. Predictions were supported: with Repeated Measures ANOVA and t-tests, we found that temperatures were more constant and higher in nests, especially when in the sun, and as the season progressed (hotter ambient temperatures). We conclude that the large mud nest of the Rufous Hornero works as an incubation chamber that likely evolved to help resolve the incubation-foraging trade-off in the very seasonal and hot regions where the bird evolved. Thus, as an incubation chamber, the nest allows the bird to forage rather than incubate thereby resolving the foraging-incubation trade-off and potentially

Nest temperature fluctuations in a cavity nester, the southern ground-hornbill.

Science.gov (United States)

Combrink, L; Combrink, H J; Botha, A J; Downs, C T

2017-05-01

Southern ground-hornbills Bucorvus leadbeateri inhabit savanna and bushveld regions of South Africa. They nest in the austral summer, which coincides with the wet season and hottest daytime temperatures in the region. They are secondary cavity nesters and typically nest in large cavities in trees, cliffs and earth banks, but readily use artificial nest boxes. Southern ground-hornbills are listed as Endangered in South Africa, with reintroductions into suitable areas highlighted as a viable conservation intervention for the species. Nest microclimate, and the possible implications this may have for the breeding biology of southern ground-hornbills, have never been investigated. We used temperature dataloggers to record nest cavity temperature and ambient temperature for one artificial and 11 natural southern ground-hornbill tree cavity nests combined, spanning two breeding seasons. Mean hourly nest temperature, as well as mean minimum and mean maximum nest temperature, differed significantly between southern ground-hornbill nests in both breeding seasons. Mean nest temperature also differed significantly from mean ambient temperature for both seasons. Natural nest cavities provided a buffer against the ambient temperature fluctuations. The artificial nest provided little insulation against temperature extremes, being warmer and cooler than the maximum and minimum local ambient temperatures, respectively. Nest cavity temperature was not found to have an influence on the breeding success of the southern ground-hornbill groups investigated in this study. These results have potentially important implications for southern ground-hornbill conservation and artificial nest design, as they suggest that the birds can tolerate greater nest cavity temperature extremes than previously thought. Copyright © 2017 Elsevier Ltd. All rights reserved.

Comparación de pruebas de diagnóstico de mansonelosis en el estudio de prevalencia en comunidades del río Atabapo, Departamento del Guanía, Colombia 1996

Directory of Open Access Journals (Sweden)

Herbert I. Espitia

1998-03-01

Full Text Available En el departamento de Guainía, Colombia, se realizó un estudio tipo encuesta de prevalencia de corte en siete comunidades del río Atabapo, donde se calculó una muestra poblacional de 181 personas mayores de 10 años que se debían examinar, tomando, como unidad de análisis, 37 viviendas escogidas aleatoriamente. Se les tomó una muestra de sangre que se examinó mediante cuatro técnicas (examen en fresco, gota gruesa, prueba de Knott y conteo por cm3, examen médico, estudio de saneamiento y encuesta por vivienda. Se encontró una prevalencia de 57% en el grupo examinado que, por ser muestra representativa de la población, se puede decir que es la prevalencia de la zona. De las tres pruebas diagnósticas utilizadas, además de la prueba de Knott, el conteo por cm3 fue la que mejor resultado brindó en el estudio, dando una sensibilidad, especificidad y valor predictivo positivo similar y mejor que la de la prueba de oro que se tomó como referencia.

Propuesta de adaptación de la prueba de abordaje luriano "evaluación neuropsicológica infantil Puebla-Sevilla" para el idioma portugués

OpenAIRE

Jamile Bittencourt-Chastinet; Caio Pereira-Gottschalk Morais; Yulia Solovieva; Luis Quintanar-Rojas

2012-01-01

Los instrumentos utilizados para la evaluación neuropsicológica infantil se pueden dividir en dos grupos: las pruebas estandarizadas y la evaluación cualitativa. Desde la perspectiva de la neuropsicología históricocultural que respalda la utilización de los procedimientos cualitativos se han realizado los intentos de elaboración y utilización clínica de las pruebas para el análisis de casos de trastornos de desarrollo y aprendizaje. El objetivo de este trabajo es proponer un instrumento para ...

The evolution of cerebellum structure correlates with nest complexity.

Science.gov (United States)

Hall, Zachary J; Street, Sally E; Healy, Susan D

2013-01-01

Across the brains of different bird species, the cerebellum varies greatly in the amount of surface folding (foliation). The degree of cerebellar foliation is thought to correlate positively with the processing capacity of the cerebellum, supporting complex motor abilities, particularly manipulative skills. Here, we tested this hypothesis by investigating the relationship between cerebellar foliation and species-typical nest structure in birds. Increasing complexity of nest structure is a measure of a bird's ability to manipulate nesting material into the required shape. Consistent with our hypothesis, avian cerebellar foliation increases as the complexity of the nest built increases, setting the scene for the exploration of nest building at the neural level.

Capacidad de esfuerzo en snowboarders: diferencias individuales en una prueba de máximo esfuerzo en half-pipe

Directory of Open Access Journals (Sweden)

J. Arruza

2005-01-01

Full Text Available El propósito de esta investigación es analizar y valorar la capacidad de realizar esfuerzos de los snowboarders, en una prueba específica. Evaluaremos dicha capacidad de trabajo individual a través de la Frecuencia cardiaca (FC, del Esfuerzo Percibido (REP y del Nivel de Fatiga Percibida (NFP, en la modalidad de Half-Pipe. Se trata de un estudio descriptivo, valorativo y correlacional de diseño cuasiexperimental unifactorial multivariado, con una muestra de n=5 sujetos, que constituyen la totalidad del equipo Olímpico español de Snowboard. La prueba diseñada ad hoc se ha realizado a 3.000 m. en el glaciar de Tignes. Las conclusiones de este estudio demuestran 1 que es posible realizar una investigación de campo en la que se cuantifique la intensidad de la tarea, y 2 que para valorar el esfuerzo debemos combinar variables fisiológicas y psicológicas. Finalmente se plantea la importancia del Nivel de Fatiga Percibida, como instrumento predictivo en el proceso de toma de decisiones.

Las pruebas pisa en Colombia: una estrategia de política exterior más que una política de educación.

OpenAIRE

Ardila Pinto, María Paula

2015-01-01

El tema que explora este trabajo es la aplicación de las pruebas PISA en Colombia. Este criterio de evaluación creado por la Organización para la Cooperación y Desarrollo Económico (OCDE) es actualmente un estándar de calidad de educación a nivel internacional y diversos países lo han implementado como una forma para evaluar la calidad de prácticas políticas educativas que han desarrollado.La propuesta de este trabajo parte de la sospecha de que la preocupación por la aplicación de las prueba...

Nested cellular automata

International Nuclear Information System (INIS)

Quasthoff, U.

1985-07-01

Cellular automata by definition consist of a finite or infinite number of cells, say of unit length, with each cell having the same transition function. These cells are usually considered as the smallest elements and so the space filled with these cells becomes discrete. Nevertheless, large pictures created by such cellular automata look very fractal. So we try to replace each cell by a couple of smaller cells, which have the same transition functions as the large ones. There are automata where this replacement does not destroy the macroscopic structure. In these cases this nesting process can be iterated. The paper contains large classes of automata with the above properties. In the case of one dimensional automata with two states and next neighbour interaction and a nesting function of the same type a complete classification is given. (author)

Fleas (Siphonaptera) in the Nests of Dormice (Gliridae: Rodentia) in Lithuania.

Science.gov (United States)

Lipatova, I; Stanko, M; Paulauskas, A; Spakovaite, S; Gedminas, V

2015-05-01

Negative effects of flea (Siphonaptera) parasitism on the host may be expressed in different ways. The aim of this study was to assess distribution of the flea fauna in nests of dormice in Lithuania. Nests of Glis glis (L.), Dryomys nitedula (Pallas), and Muscardinus avellanarius (L.) were collected from nest boxes in 2012 and 2013. Fleas were collected from nests in the laboratory and put into plastic tubes with 70% ethanol. Flea species were identified using morphological keys. From 400 nest boxes, 112 nests of dormice were collected from eight sites from mixed forests of central Lithuania. Twenty-three nests of G. glis were collected from nest boxes, with 16 of them containing 286 fleas belonging to four species: Ceratophyllus sciurorum (Schrank) (259), C. gallinae (Schrank) (23), Hystrichopsylla talpae (Curtis) (3), and Megabothris turbidus (Rothschild) (1). Fourteen nests of M. avellanarius were collected from nest boxes, 4 of which contained 224 fleas belonging to two species: C. sciurorum (221) and C. gallinae (3). Twenty-four nests of D. nitedula were collected from nest boxes, including 17 containing 207 fleas belonging to two species: C. sciurorum (205) and C. gallinae (2). Fifty-one nests of undetermined dormice species also were collected from nest boxes, 12 of them contained 395 fleas belonging to three species: C. sciurorum (374), Ctenophthalmus agyrtes (Heller) (19), and Ctenophthalmus assimilis (Taschenberg) (2). C. sciurorum was a predominant species in the nests of dormice. The occurrence of C. gallinae was documented in Lithuania for the first time. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

From neurons to nests : nest-building behaviour as a model in behavioural and comparative neuroscience

OpenAIRE

Hall, Zachary Jonas; Meddle, Simone L; Healy, Susan Denise

2015-01-01

This work was supported by funding from the Biotechnology and Biological Sciences Research Council (BB/ I019502/1 to SDH and SLM) and the Natural Sciences and Engineering Research Council of Canada (grant number PGSD3-409582-2011 to ZJH) and Roslin Institute Strategic Grant funding from the Biotechnology and Biological Sciences Research Council (SLM). Despite centuries of observing the nest building of most extant bird species, we know surprisingly little about how birds build nests and, s...

Nest predation research: Recent findings and future perspectives

Science.gov (United States)

Chalfoun, Anna D.; Ibanez-Alamo, J. D.; Magrath, R. D.; Schmidt, Kenneth A.; Thomson, R. L.; Oteyza, Juan C.; Haff, T. M.; Martin, T.E.

2016-01-01

Nest predation is a key source of selection for birds that has attracted increasing attention from ornithologists. The inclusion of new concepts applicable to nest predation that stem from social information, eavesdropping or physiology has expanded our knowledge considerably. Recent methodological advancements now allow focus on all three players within nest predation interactions: adults, offspring and predators. Indeed, the study of nest predation now forms a vital part of avian research in several fields, including animal behaviour, population ecology, evolution and conservation biology. However, within nest predation research there are important aspects that require further development, such as the comparison between ecological and evolutionary antipredator responses, and the role of anthropogenic change. We hope this review of recent findings and the presentation of new research avenues will encourage researchers to study this important and interesting selective pressure, and ultimately will help us to better understand the biology of birds.

Prototipos de prueba de acelerómetro y conexión Bluetooth para terminales Android

OpenAIRE

Velasco Gracia, Raúl

2012-01-01

Los objetivos que persigue este PFC son los siguientes: +Estudio de la plataforma Android y el empleo del acelerómetro y opcionalmente el giroscopio para enviar ordenes a un robot móvil. + Realización y prueba de una aplicación que haga uso de tales recursos. + Elaboración de una memoria que pueda utilizarse con propósito docente. Escuela Técnica Superior de Ingeniería de Telecomunicación Universidad Politécnica de Cartagena

Prueba comparativa de uniformidad de contenido en tabletas de teofilina (150 mg/tab de dos casas farmacéuticas en Costa Rica

Directory of Open Access Journals (Sweden)

Esteban Pérez-López

2014-05-01

Full Text Available Dada la importancia del medicamento denominado teofilina para su uso en pacientes con problemas de asma y su alto consumo en Costa Rica, se eligió el producto en tabletas de 150 mg de teofilina de una casa farmacéutica que lo produce y distribuye en forma genérica, junto con el que fabrica la Caja Costarricense de Seguro Social (CCSS en la misma dosis. Se realizó el estudio comparativo de la prueba de uniformidad de contenido para las tabletas de teofilina de 150 mg de la casa farmacéutica LISAN y las fabricadas por la CCSS. La prueba de uniformidad de contenido analíticamente se fundamentó en la absorción y cuantificación del ingrediente activo teofilina a 272 nm para 10 muestras de cada casa farmacéutica, mediante el uso de un espectrofotómetro UV/Vis, empleando como disolvente agua destilada. Se probó un método selectivo, exacto y preciso y se obtuvo como resultado que todas las dosis ensayadas para cada fabricante se encuentran en el rango de 100% a 110%, con respecto a lo etiquetado sobre el principio activo en las tabletas y con un desvío relativo no mayor al 2,5%, cumpliendo holgadamente con lo establecido por la Farmacopea de Estados Unidos para la prueba de uniformidad de contenido.

Breeding biology and nest site characteristics of the Rosy-faced ...

African Journals Online (AJOL)

Nine colonies, comprising 20 nests, were monitored every four days to establish incubation and fledging periods. Rearing and fledging of chicks was found to be successful in eight nests. Measurements of 18 young from four nests were used to monitor growth rate. Nesting success was calculated at 0.1, following the ...

Coping with shifting nest predation refuges by European reed Warblers Acrocephalus scirpaceus.

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Lucyna Halupka

Full Text Available Predation, the most important source of nest mortality in altricial birds, has been a subject of numerous studies during past decades. However, the temporal dynamics between changing predation pressures and parental responses remain poorly understood. We analysed characteristics of 524 nests of European reed warblers monitored during six consecutive breeding seasons in the same area, and found some support for the shifting nest predation refuge hypothesis. Nest site characteristics were correlated with nest fate, but a nest with the same nest-site attributes could be relatively safe in one season and vulnerable to predation in another. Thus nest predation refuges were ephemeral and there was no between-season consistency in nest predation patterns. Reed warblers that lost their first nests in a given season did not disperse farther for the subsequent reproductive attempt, compared to successful individuals, but they introduced more changes to their second nest sites. In subsequent nests, predation risk remained constant for birds that changed nest-site characteristics, but increased for those that did not. At the between-season temporal scale, individual birds did not perform better with age in terms of reducing nest predation risk. We conclude that the experience acquired in previous years may not be useful, given that nest predation refuges are not stable.

Observer visitation frequency and success of mourning dove nests: A field experiment

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Nichols, J.D.; Percival, H.F.; Coon, R.A.; Conroy, M.J.; Hensler, G.L.; Hines, J.E.

1984-01-01

Field studies of nesting success generally require visits by the investigator to the nests under study. Such visits may themselves influence nesting success, however, and this possibility has been discussed and investigated by a number of workers with a variety of bird species. Livezey (1980) reviewed the relevant literature for duck nests and noted that most studies failed to demonstrate differences in nesting success between visited nests and those not visited. Livezey (1980) found in his own work that nest abandonment may have occurred as a result of disturbance by observers but that nest predation was not related to time spent by observers at nests or number of observers approaching nests. Various components of nesting and breeding success in seabirds are thought to be adversely affected by human disturbance and nest visitation (Gillett et al. 1975, Robert and Ralph 1975, Ollason and Dunnet 1980). Upland, ground-nesting species have also been studied (e.g. Stoddard 1931, Evans and Wolfe 1967, Henry 1969, Roseberry and Klimstra 1970, Klimstra and Roseberry 1975), and, although conclusions have varied, a number of these workers found no effect of observers on nest-predation rates.

Prueba de hipótesis sobre la existencia de una raíz fraccional en una serie de tiempo no estacionaria

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Diego Fernando Lemus Polanía

2013-06-01

Full Text Available En este trabajo se propone una modificación de la prueba de hipótesis propuesta por Castaño, Gómez y Gallón (2008 para determinar la existencia de memoria larga en un proceso ARFIMA(p,d,q estacionario e invertible. En el caso puntual de los procesos ARFIMA(p,d,q, esta modificación permite determinar la existencia de una raíz fraccional en una serie de tiempo no estacionaria cuyo componente ARMA de corto plazo es indeterminado o desconocido. Vía simulaciones de Monte Carlo, se validan los resultados analíticos obtenidos en el trabajo y se demuestra el buen comportamiento de la prueba propuesta, en términos de potencia y tamaño, en comparación con otras metodologías disponibles en la literatura.

Evaluación de las pruebas dot blot y aglutinación de látex para el diagnóstico de cisticercosis en Perú

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Eduardo Miranda-Ulloa

Full Text Available Con el objetivo de evaluar las pruebas dot blot y aglutinación de látex para la detección de cisticercosis humana con antígeno de líquido de cisticerco de Taenia solium, se usaron 125 sueros humanos, de los cuales 60 procedían de personas con cisticercosis confirmada por Western Blot, 45 de personas con otras enfermedades parasitarias y 20 de personas aparentemente sanas. La concentración óptima del antígeno para impregnar las tiras dot blot fue de 0,01 ug/uL, y para impregnar las partículas de látex fue de 0,092 ug/uL. Para la prueba dot blot se encontró una sensibilidad del 100% y especificidad del 87,7%; para la aglutinación de látex una sensibilidad del 93,3% y especificidad del 89,2%. Ambas pruebas podrían ser de utilidad y factibles de implementar como alternativas de diagnóstico serológico en laboratorios de áreas endémicas del Perú

Sandhill crane abundance and nesting ecology at Grays Lake, Idaho

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Austin, J.E.; Henry, A.R.; Ball, I.J.

2007-01-01

We examined population size and factors influencing nest survival of greater sandhill cranes (Grus canadensis tabida) at Grays Lake National Wildlife Refuge, Idaho, USA, during 1997-2000. Average local population of cranes from late April to early May, 1998-2000, was 735 cranes, 34% higher than that reported for May 1970-1971. We estimated 228 (SE = 30) nests in the basin core (excluding renests), 14% higher than a 1971 estimate. Apparent nest success in our study (x?? = 60%, n = 519 nests) was lower than reported for Grays Lake 30-50 years earlier. Daily survival rates (DSRs) of all nests averaged 0.9707 (41.2%). The best model explaining nest survival included year and water depth and their interaction. Nest survival was highest (DSR = 0.9827) in 1998 compared with other years (0.9698-0.9707). Nest survival changed little relative to water depth in 1998, when flooding was extensive and alternative prey (microtines) irrupted, but declined markedly with lower water levels in 2000, the driest year studied. Hypotheses relating nest survival to vegetation height, land use (idle, summer grazing, fall grazing), and date were not supported. In a before-after-control-impact design using 12 experimental fields, nest survival differed among years but not among management treatments (idle, fall graze, fall burn, and summer-graze-idle rotation), nor was there an interaction between year and treatments. However, DSRs in fall-burn fields declined from 0.9781 in 1997-1998 to 0.9503 in 1999-2000 (posttreatment). Changes in the predator community have likely contributed to declines in nest success since the 1950s and 1970s. Our results did not support earlier concerns about effects of habitat management practices on crane productivity. Nest survival could best be enhanced by managing spring water levels. Managers should continue censuses during late April to evaluate long-term relationships to habitat conditions and management.

Management of western coniferous forest habitat for nesting accipiter hawks

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Richard T. Reynolds

1983-01-01

Availability of nesting sites can limit accipiter populations. Because accipiters nest in dense forest stands, any alteration that opens these stands is likely to lessen their desirability as nest sites. Tree growth and the associated changes in the vegetative structure of aging nest sites limit the number of years sites will be suitable. Therefore, prospective...

Variation in nest predation among arid-zone birds | Lloyd | Ostrich ...

African Journals Online (AJOL)

I examined the nesting habits and success of 11 co-existing species in an arid, sub-tropical habitat in South Africa. Nesting success ranged from 3.5% to 75.4% among species, with predation by mammals and snakes accounting for 94% of nest losses. Differences in predator avoidance behaviour (deserting the nest vs ...

Nesting ecology of Pied Avocet Recurvirostra avosetta in Sfax salina ...

African Journals Online (AJOL)

In this paper we use the results of a one-year monitoring of nests in Sfax salina to provide information on its nesting parameters, in particular nesting phenology, colony size and hatching success. Our results show that Pied Avocets formed dense colonies at the beginning of the nesting season, but colony size decreased as ...

Memoria de trabajo en niños escolarizados: efecto de intervalos de presentación y distractores en la prueba computarizada Memonum

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Carlos Arturo Conde Cotes

2013-06-01

Full Text Available La presente investigación evaluó la memoria de trabajo visual a través de la prueba computarizada Memonum en niños escolarizados. Se evaluaron los efectos de tres tiempos de exposición (1, 4 y 8 segundos y de la presentación de un distractor sobre el desempeño mnemónico en la prueba Memonum en 72 niños pertenecientes a un colegio del área metropolitana de Bucaramanga, Colombia, con edades entre 8 y 11 años de los grados tercero, cuarto y quinto de primaria. Se encontró una diferencia significativa entre los tiempos de exposición en las variables número de aciertos y aciertos acumulados, demostrandoun mejor desempeño mnemónico en los participantes que presentaron la prueba en el tiempo de 8 segundos en comparación con los niños pertenecientes al grupo de 1 segundo; además, la presencia del distractor demostró una diferencia significativa en los aciertos y aciertos acumulados, considerándose como un estímulo generador de interferencia que perturba la capacidad de almacenamiento de la memoria de trabajo en niños. Adicionalmente, se halló una diferencia significativa en cuanto al uso de la estrategia de repetición mental, indicando que los participantes de los grupos de 4 y 8 segundos leasignaron mayor puntaje que los niños del grupo de 1 segundo. Un amplio tiempo de exposición de estímulos en la prueba Memonum aumenta la capacidad de retención; asimismo, el empleo de un distractor afecta en los participantes la capacidad de almacenamiento y esta, a suvez, aumenta de acuerdo a la progresión escolar, debidoal uso de las estrategias mnemónicas que los niños utilizan para garantizar el recuerdo de las series numéricas.

Tuberculosis testing among populations with high HIV risk in Tijuana, Baja California, Mexico Prueba de tuberculosis en poblaciones con riesgo alto de VIH en Tijuana, Baja California, México

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Michele G. Velasquez

2012-07-01

Full Text Available OBJECTIVE: To assess the prevalence of prior tuberculin skin testing (TST among populations at risk for HIV infection in Tijuana, Mexico, and to identify factors associated with TST. METHODS: Sex workers, injection drug users, noninjecting drug users, and homeless persons > 18 years old were recruited by using targeted sampling for risk assessment interviews and serologic testing for HIV and Mycobacterium tuberculosis infection. Univariate and multivariate logistic regression were used to identify correlates of self-reported TST history. RESULTS: Of 502 participants, 38.0% reported prior TST, which was associated with previous incarceration in the United States of America [odds ratio (OR = 13.38; 95% confidence interval (CI = 7.37-24.33] and injection drug use (OR = 1.99; 95% CI = 1.27- 3.11. Positive results on serologic tests for M. tuberculosis infection (57% and HIV (4.2% were not associated with a prior TST. CONCLUSIONS: A history of TST was lower in HIV-positive participants even though TST is indicated for persons with HIV in Mexico. Fewer than half the individuals at high risk for HIV in this study had a history of TST; however, TST was fairly common among those individuals with a prior history of incarceration. Increased tuberculosis screening is needed for populations at risk of contracting HIV in Tijuana, particularly those outside of criminal justice settings.OBJETIVO: Evaluar la prevalencia de la prueba de la tuberculina previa, e identificar los factores asociados con ella, en poblaciones con riesgo de infección por el VIH en Tijuana, México. MÉTODOS: Se reclutó a profesionales del sexo, consumidores de drogas inyectables y no inyectables y personas sin hogar > 18 años de edad mediante un muestreo dirigido a fin de efectuar entrevistas para evaluar el riesgo y pruebas serológicas para la infección por el VIH y Mycobacterium tuberculosis. Para identificar la correlación de los antecedentes de la prueba de la tuberculina

High, low, or familiar? Nest site preferences of experienced laying hens.

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Krause, E T; Schrader, L

2018-05-22

1. The aim of this study was to investigate which nest heights are preferred by laying hens in the absence of familiar nest locations and whether preferred nest heights are more attractive than a familiar location. In two experiments, a total of 108 hens of four different layer breeds, which were at least 50 weeks of age, were studied. 2. In the first experiment, hens were given individual free choice between nests for 1-week at four different heights (0 cm, 39 cm, 78 cm, and 117 cm above ground). Hens of the four breeds differed in their nest height preferences (P = 0.0013). However, hens of three breeds preferred ground level nests (P < 0.007) and the fourth line showed an equal preference for the ground level and level three, the latter level corresponding to the height of the nests in their home compartments. 4. In the second experiment, hens from the four breeds were given a choice between ground level nests and nests at a familiar location, i.e. at the same location as in their home compartment. Hens of all strains preferred the familiar nest location (P = 0.002) and preferences did not differ between strains (P = 0.77). 5. Laying hens seem to prefer nests at ground level in the absence of a familiar nest. However, if possible, experienced 50 week old hens continue to use a familiar nest location instead of a ground nest location. The results are discussed with respect to a potential primary preference that may be modifiable by experience and with respect to possible relevance in commercial housing.

Relationship between test of postural control and strength and ability tests in basketball players. [Relación entre las pruebas de control postural y las pruebas de fuerza y habilidad en jugadores de baloncesto].

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Abbas Asadi

2018-04-01

Full Text Available Abstract This study investigated the relationship between performance tests (i.e., jumping ability, strength, sprint and change of direction ability and dynamic postural control in young basketball players. Twenty-three young basketball players participated in this study and performed measurements of dynamic balance (Star Excursion Balance Test [SEBT], countermovement jump (CMJ, broad long jump (BLJ, 4×9-m shuttle run, agility T test (TT, Illinois agility test (IAT, 20-m sprint and lower extremity muscle strength. Significant association was observed between balance (at medial direction and strength performance (r = 0.523, p < 0.05. Significant positive correlations were detected between directions of SEBT and BLJ (r = -0.466 to -0.479, p < 0.05, 4×9-m shuttle run (r = -0.403 to 0.486, p < 0.05, TT (r = -0.410, p < 0.05, IAT (r = 0.435, p < 0.05 and sprint (r = -0.402 to 0.452, p < 0.05. Postural control is more in relation to change of direction ability, sprint and power performance in basketball athletes. Resumen Este estudio investigó la relación entre las pruebas de rendimiento y el control postural dinámico en jóvenes jugadores de baloncesto. Veintitrés jóvenes jugadores de baloncesto participaron en este estudio y realizaron mediciones de equilibrio dinámico (Prueba de Balance de Excursión Estrella [SEBT], salto de contramovimiento (CMJ, salto largo en longitud (BLJ, lanzamiento de 4 × 9 m, test T de agilidad (TT, prueba de agilidad de Illinois (IAT, sprint de 20 m y fuerza muscular de las extremidades inferiores. Se observó una asociación significativa entre el equilibrio (en la dirección medial y el rendimiento de la fuerza (r = 0.523, p <0.05. Se detectaron correlaciones positivas significativas entre las direcciones de SEBT y BLJ (r = -0,466 a -0,479, p <0,05, carrera con cambios de sentido de 4 × 9 m (r = -0,403 a 0,486, p <0,05, TT (r = 0,410, p <0,05, IAT (r = 0,435, p <0,05 y sprint (r = -0,402 a 0,452, p <0,05. El

Ecology of a nesting red-shouldered hawk population

Science.gov (United States)

Stewart, R.E.

1949-01-01

An ecological study of a nesting Red-shouldered Hawk population was made over a 185 square mile area on the Coastal Plain of Maryland in 1947. The courting and nesting season extended from late February until late June.....During the nesting season a combination of fairly extensive flood-plain forest with adjacent clearings appears to meet the major ecological requirements of the Red-shouldered Hawk in this region. A total of 51 pairs was found in the study area, occupying about 42 square miles or 23% of the total area studied. The population density on the land that was suitable for this species was about 1 pair per .8 of a square mile, while the density for the entire study area would be only about 1 pair per 3.6 square miles.....Nests were spaced fairly evenly over most of the flood-plain forests, especially in areas where the width.of the flood plain was relatively constant. There was an inverse correlation between the width of the flood plain and the distances between nests in adjacent territories. The nests were all situated in fairly large trees and were from 28 feet to 77 feet above the ground, averaging 50. They were found in 14 different species of trees, all deciduous.....The Barred Owl and Red-shouldered Hawk were commonly associated together in the same lowland habitats. Other raptores were all largely restricted to upland habitats....The average number of young in 47 occupied nests following the hatching period was 2.7 with extremes of 1 and 4. Only 3 out of 52 nests (6%) were found deserted at this time....The food habits of nestling Red-shouldered Hawks are very diversified. They feed on many types of warm-blooded and cold-blooded vertebrates as well as invertebrates.

Nest success of the Indian House Crow Corvus splendens : An ...

African Journals Online (AJOL)

Nest success of the Indian House Crow Corvus splendens was studied in the urban area of Dar es Salaam, Tanzania, in late March to early May 2011. The study investigated nest success of the Indian House Crow in different tree species with varying canopy covers and heights. Fifty-five active nests and 38 inactive nests ...

Landscape and regional context differentially affect nest parasitism and nest predation for Wood Thrush in central Virginia, USA (Presentation)

Science.gov (United States)

Many empirical studies have shown that forest-breeding songbirds suffer greater rates of nest predation and nest parasitism in smaller forest patches and in fragmented landscapes. To compare the performance of different metrics of spatial habitat configuration resulting from defo...

Diferencias en el desempeño en pruebas de software visual en función del género. Un estudio con jugadores y jugadoras de baloncesto de 13 años

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Juan Granda Vera

2006-01-01

Full Text Available En el presente artículo se presenta un estudio llevado a cabo con jugadores y jugadoras de 13 años de edad, pertenecientes al programa de selección de talentos de la Federación Española de Baloncesto, tratando de evaluar la influencia del género en los valores de "software visual", medido en términos de tiempo de respuesta y conocimiento de las acciones que determinan una acción anticipatoria en situaciones 1 contra 1 en baloncesto. Se ha sometido a los sujetos participantes a dos pruebas mediante el programa Reflex y el sistema Pantallex, diseñados y desarrollados por los autores de este trabajo, midiendo el número de aciertos y errores en dichas respuestas y el tiempo de respuesta en milisegundos. Los resultados muestran que las jugadoras alcanzan mejores desempeños en el número de aciertos en la capacidad de anticipación perceptiva y en el conocimiento de las acciones en la prueba realizada con el programa Reflex y un mejor tiempo de respuesta en ambas pruebas, habiendo encontrado diferencias significativas entre ambos grupos en el número de aciertos en la prueba con el programa Reflex y en los tres índices de la capacidad de anticipación perceptiva, los correspondientes a ambas pruebas y el índice medio de las dos.

[Duration of the pre-nesting period and its relation with social organization in sandpipers (Charadrii, Aves) nesting in north-east Yakutia].

Science.gov (United States)

Gavrilov, V V

2013-01-01

Investigations were carried out at two stations of Ornithological Unit, IBPN FEB RAS, located in Nizhnekolymsk District, Yakutia, starting from May 18-20 in 1984, 1985, 1987, 1988 and 1990. Duration of the pre-nesting period in 11 sandpiper species with different social organization was studied and compared with each other by allometric equations. As a characteristic of bird size the body mass was selected. Sandpipers come flying to the tundra at almost critical temperatures, to begin breeding as early as possible. Tining of breeding depends on birds feeding manner and the proximity to sites of overwintering. Duration of the pre-nesting period is invariable for every bird species and sex. There are sexual distinctions in time spent for the pre-nesting period in jointly-nesting sandpipers. The exponents in allometric equations that relate duration of the pre-nesting period with body mass are constant within a particular sex and differ between males and females. In different sexes, time spent for the pre-nesting period depends on mating, parental, and territorial systems. In sandpipers' males and females, this time is determined by the type of social organization. Relatively large sandpiper species seek to shortening of the pre-nesting period calendar time, which constrains their social organization. Monogamy and pair parental care lead to a necessity for spatial population structure to be controlled more strictly and maintained for a longer time. This, in turn, causes the increasing of males' time expenditures for such a behavior.

Retirement investment theory explains patterns in songbird nest-site choice

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Streby, Henry M.; Refsnider, Jeanine M.; Peterson, Sean M.; Andersen, David E.

2014-01-01

When opposing evolutionary selection pressures act on a behavioural trait, the result is often stabilizing selection for an intermediate optimal phenotype, with deviations from the predicted optimum attributed to tracking a moving target, development of behavioural syndromes or shifts in riskiness over an individual's lifetime. We investigated nest-site choice by female golden-winged warblers, and the selection pressures acting on that choice by two fitness components, nest success and fledgling survival. We observed strong and consistent opposing selection pressures on nest-site choice for maximizing these two fitness components, and an abrupt, within-season switch in the fitness component birds prioritize via nest-site choice, dependent on the time remaining for additional nesting attempts. We found that females consistently deviated from the predicted optimal behaviour when choosing nest sites because they can make multiple attempts at one fitness component, nest success, but only one attempt at the subsequent component, fledgling survival. Our results demonstrate a unique natural strategy for balancing opposing selection pressures to maximize total fitness. This time-dependent switch from high to low risk tolerance in nest-site choice maximizes songbird fitness in the same way a well-timed switch in human investor risk tolerance can maximize one's nest egg at retirement. Our results also provide strong evidence for the adaptive nature of songbird nest-site choice, which we suggest has been elusive primarily due to a lack of consideration for fledgling survival.

A new bee species that excavates sandstone nests.

Science.gov (United States)

Orr, Michael C; Griswold, Terry; Pitts, James P; Parker, Frank D

2016-09-12

Humanity has long been fascinated by animals with apparently unfavorable lifestyles [1]. Nesting habits are especially important because they can limit where organisms live, thereby driving population, community, and even ecosystem dynamics [2]. The question arises, then, why bees nest in active termite mounds [3] or on the rim of degassing volcanoes, seemingly preferring such hardship [4]. Here, we present a new bee species that excavates sandstone nests, Anthophora (Anthophoroides) pueblo Orr (described in Supplemental Information, published with this article online), despite the challenges already inherent to desert life. Ultimately, the benefits of nesting in sandstone appear to outweigh the associated costs in this system. Copyright © 2016 Elsevier Ltd. All rights reserved.

Provisioning nest material for Rooks; a potential tool for conservation management

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Horváth Éva

2015-06-01

Full Text Available Active conservation measures often entail supplementing scarce resources, such as food or nesting site to high conservation value species. We hypothesized that adequate nest material in reasonable distance is a scarce resource for Rooks breeding in open grassland habitats of Hungary. Here we show that Rooks willingly utilize large quantities of provided excess nesting material, and that this procedure may alter nest composition, and increase the number of successful pairs. Our results show that while nest height remains constant, twig diameter is significantly larger, the number of twigs used per nest is presumably smaller, and that the ratio of nests with fledglings is higher in a rookery where supplementary twigs were present. Providing twigs and branches in the vicinity of rookeries may serve as an active conservation measure to increase the number of nests in a rookery, and thus the potential number of nesting possibilities for Red-footed Falcons.

Cinereous Vulture Nesting Ecology in Ikh Nartyn Chuluu Nature Reserve, Mongolia

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Richard P. Reading

2005-06-01

Full Text Available Cinereous vultures ( Aegypius monachus are the largest raptors in Eurasia. Little is known about the species, especially in Mongolia. We studied the nesting ecology of cinereous vultures in Ikh Nartyn Chuluu Nature Reserve, Dornogobi Aimag. To assess reproductive success, we located active nests and periodically checked to determine if they remained active. We measured nest sizes and, periodically, nestling sizes and weights. We located 42 active cinereous vulture nests (27 on rocks and 15 on trees in 2003 and 19 nests (14 on rocks and 5 on trees in 2004. Mean volume of active nests was 3.92 ± 0.39 m 3 ( n = 36. Most nests failed prior to egg hatching, but after hatching nesting success rates increased dramatically. Following hatching, cinereous vulture chicks grew linearly until leveling off just prior to fledging. We generated growth curves for chicks that allowed us to determine the average size of chicks on specific dates. Improving the prospects for successful cinereous vulture conservation likely requires a better understanding of nesting ecology. As such, we plan to improve the quality of our data by monitoring nests more intensively to determine incubation and fledging lengths, as well as causes of nest failures.

Nest-site partitioning in a strandveld shrubland bird community ...

African Journals Online (AJOL)

Nest-site selection may vary adaptively among co-existing species as a result of competitive interactions among the species or in response to density-dependent nest predation. We examined nest-site characteristics and degree of partitioning among 14 co-existing bird species breeding in dwarf strandveld shrubland at ...

Lifespan analyses of forest raptor nests: patterns of creation, persistence and reuse.

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María V Jiménez-Franco

Full Text Available Structural elements for breeding such as nests are key resources for the conservation of bird populations. This is especially true when structural elements require a specific and restricted habitat, or if the construction of nests is costly in time and energy. The availability of nesting-platforms is influenced by nest creation and persistence. In a Mediterranean forest in southeastern Spain, nesting-platforms are the only structural element for three forest-dwelling raptor species: booted eagle Aquila pennata, common buzzard Buteo buteo and northern goshawk Accipiter gentilis. From 1998 to 2013, we tracked the fate of 157 nesting-platforms built and reused by these species with the aim of determining the rates of creation and destruction of nesting-platforms, estimating nest persistence by applying two survival analyses, describing the pattern of nest reuse and testing the effects of nest use on breeding success. Nest creation and destruction rates were low (0.14 and 0.05, respectively. Using Kaplan Meier survival estimates and Cox proportional-hazards regression models we found that median nest longevity was 12 years and that this was not significantly affected by nest characteristics, nest-tree dimensions, nest-builder species, or frequency of use of the platform. We also estimated a transition matrix, considering the different stages of nest occupation (vacant or occupied by one of the focal species, to obtain the fundamental matrix and the average life expectancies of nests, which varied from 17.9 to 19.7 years. Eighty six percent of nests were used in at least one breeding attempt, 67.5% were reused and 17.8% were successively occupied by at least two of the study species. The frequency of nest use had no significant effects on the breeding success of any species. We conclude that nesting-platforms constitute an important resource for forest raptors and that their longevity is sufficiently high to allow their reuse in multiple breeding

Lifespan Analyses of Forest Raptor Nests: Patterns of Creation, Persistence and Reuse

Science.gov (United States)

Jiménez-Franco, María V.; Martínez, José E.; Calvo, José F.

2014-01-01

Structural elements for breeding such as nests are key resources for the conservation of bird populations. This is especially true when structural elements require a specific and restricted habitat, or if the construction of nests is costly in time and energy. The availability of nesting-platforms is influenced by nest creation and persistence. In a Mediterranean forest in southeastern Spain, nesting-platforms are the only structural element for three forest-dwelling raptor species: booted eagle Aquila pennata, common buzzard Buteo buteo and northern goshawk Accipiter gentilis. From 1998 to 2013, we tracked the fate of 157 nesting-platforms built and reused by these species with the aim of determining the rates of creation and destruction of nesting-platforms, estimating nest persistence by applying two survival analyses, describing the pattern of nest reuse and testing the effects of nest use on breeding success. Nest creation and destruction rates were low (0.14 and 0.05, respectively). Using Kaplan Meier survival estimates and Cox proportional-hazards regression models we found that median nest longevity was 12 years and that this was not significantly affected by nest characteristics, nest-tree dimensions, nest-builder species, or frequency of use of the platform. We also estimated a transition matrix, considering the different stages of nest occupation (vacant or occupied by one of the focal species), to obtain the fundamental matrix and the average life expectancies of nests, which varied from 17.9 to 19.7 years. Eighty six percent of nests were used in at least one breeding attempt, 67.5% were reused and 17.8% were successively occupied by at least two of the study species. The frequency of nest use had no significant effects on the breeding success of any species. We conclude that nesting-platforms constitute an important resource for forest raptors and that their longevity is sufficiently high to allow their reuse in multiple breeding attempts. PMID

Interspecific nest parasitism by chukar on greater sage-grouse

Science.gov (United States)

Fearon, Michelle L.; Coates, Peter S.

2014-01-01

Nest parasitism occurs when a female bird lays eggs in the nest of another and the host incubates the eggs and may provide some form of parental care for the offspring (Lyon and Eadie 1991). Precocial birds (e.g., Galliformes and Anseriformes) are typically facultative nest parasites of both their own and other species (Lyon and Eadie 1991). This behavior increases a female’s reproductive success when she parasitizes other nests while simultaneously raising her own offspring. Both interspecific and conspecific nest parasitism have been well documented in several families of the order Galliformes, particularly the Phasianidae (Lyon and Eadie 1991, Geffen and Yom-Tov 2001, Krakauer and Kimball 2009). The Chukar (Alectoris chukar) has been widely introduced as a game bird to western North America from Eurasia and is now well established within the Great Basin from northeastern California east to Utah and north to Idaho and Oregon (Christensen 1996). Over much of this range the Chukar occurs with other phasianids, including the native Greater Sage-Grouse (Centrocercus urophasianus), within sagebrush (Artemisia spp.) steppe (Christensen 1996, Schroeder et al. 1999, Connelly et al. 2000). Chukar typically exploit a broader range of habitats than do sage-grouse, but both species use the same species of sagebrush and other shrubs for nesting cover (Christensen 1996, Schroeder et al. 1999). Chukar are known to parasitize nests of other individuals of their own species (Geffen and Yom-Tov 2001), but we are unaware of reported evidence that Chukar may parasitize nests of sage-grouse. Here we describe a case of a Chukar parasitizing a sage-grouse nest in the sagebrush steppe of western Nevada.

Habitat characteristics of nesting areas and of predated nests in a Mediterranean population of the European pond turtle, Emys orbicularis galloitalica

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Marco A.L. Zuffi

2006-01-01

Full Text Available one of the largest population of Emys orbicularis galloitalica of central Italy inhabits the canal system wet areas within a natural protected park. Features of nesting habitats, nest structure, and predation patterns of 209 nests of a large population of the European pond turtle are here presented and analysed. Nest sites were characterised by sunny bushy areas in strip habitat, digged along north-south oriented canals, on average with about 26% of the area covered by vegetation, less than one meter distant from 30 cm height bushes, at about 11 m from water and at about 13 m distance from wooded areas, 28 m away from a road. Principal Component and discriminant analyses were used on 20 selected variables in order to reduce the number of physical variables, and indicate that canal border, strip habitat, and canal orientation are grouping variables, that correctly classified 41.6%, 66.5%, and 100 % respectively of nest presence.

Daphnia exilis Herrick, 1895 (Crustacea: Cladocera): Una especie zooplanctónica potencialmente utilizable como organismo de prueba en bioensayos de toxicidad aguda en ambientes tropicales y subtropicales

OpenAIRE

MARTÍNEZ-JERÓNIMO, Fernando; RODRÍGUEZ-ESTRADA, Jesús; MARTÍNEZ-JERÓNIMO, Laura

2008-01-01

La evaluación biológica de los efectos tóxicos que producen los contaminantes químicos sobre los organismos acuáticos es fundamental para establecer medidas de control que restrinjan o limiten la contaminación en los ecosistemas acuáticos receptores de descargas. Para realizar esta valoración con frecuencia se emplean como organismos de prueba a diferentes especies planctónicas, siendo Daphnia magna el cladócero más utilizado en todo el mundo en pruebas de toxicidad, pese a que su utilidad en...

Nesting biology of four Tetrapedia species in trap-nests (Hymenoptera:Apidae:Tetrapediini

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Evandro Camillo

2005-06-01

Full Text Available The nests used in this study were obtained from trap-nests (tubes of cardboard and cut bamboo stems placed on Santa Carlota Farm (Itaoca Section-IS, Santana Section-SS and Cerrado-Ce, Cajuru, SP, Brazil. The number of nests and corresponding species obtained were as follows: 516 nests of T. curvitarsis, 104 of T. rugulosa, 399 of T. diversipes and 98 of T. garofaloi. The most abundant species from SS and Ce was T.curvitarsis, and from IS it was T. diversipes. In general, most nests were collected during the hot and wet season (September to April. The nests were constructed with sand and an oily substance, and a single female established them. The cells were constructed in a linear series, sometimes followed by a vestibular cell. The number of brood cells ranged from 1 to 10 in T. curvitarsis (n=200, and in T. garofaloi (n=51, from 1 to 8 (n=30 in T. rugulosa, and from 1 to 6 (n=37 in T. diversipes. The pollen mass (pollen + oily substance contained a hollow, sometimes divided by a transverse ridge, on the exposed face of the pollen mass. The egg was vertically positioned in the lower part of the hollow. At times, the closing of a cell was initiated before provisioning was completed, with a construction of a collar at the cell limit. In some nests the final cellular partition also acted as a closure plug. Females began activities at 6:18 a.m.and ended between 3:31 and 6:26 p.m. Some females (T. curvitarsis , T. rugulosa and T. garofaloi did not spend the nights at their nests, returning to them only the following morning with additional material. In general, the development period (for males and females was greater in nests collected near the end of the hot and wet season than it was for nests collected in other months. Sex ratios for each species were as follows: T. curvitarsis, 1:1; T. rugulosa , 1.6:1 female; T. diversipes, 1.9:1; T. garofaloi, 2.8:1. Males and females of T. diversipes exhibited statistically similar sizes and in the other

Archiving California’s historical duck nesting data

Science.gov (United States)

Ackerman, Joshua T.; Herzog, Mark P.; Brady, Caroline; Eadie, John M.; Yarris, Greg S.

2015-07-14

The U.S. Geological Survey (USGS), in partnership with the California Waterfowl Association (CWA) and other organizations, have compiled large datasets on the nesting ecology and management of dabbling ducks and associated upland nesting birds (Northern Harriers [Circus cyaneus], Short-eared Owls [Asio flammeus], Ring-necked Pheasants [Phasianus colchicus], and American Bitterns [Botaurus lentiginosus]) throughout California on Federal Refuges, State Wildlife Areas, and private lands, some participating in State and Federal habitat programs. These datasets encompass several long-term monitoring programs at multiple sites throughout California, and include data from more than 26,000 nests and span nearly 30 years.

Prueba de Elisa indirecta del lisado total de Bartonella bacilliformis para el diagnóstico rápido de la enfermedad de Carrión

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Elizabeth Anaya

2008-04-01

Full Text Available Se elaboró y estandarizó una prueba de ELISA indirecta con el lisado total de Bartonella bacilliformis procedentes de una cepa ATCC y de un aislamiento clínico. Se seleccionaron 86 sueros de pacientes con diagnóstico confirmado de enfermedad de Carrión por frotis y cultivo, 51 sueros negativos de pacientes de zonas no endémicas y 32 sueros de pacientes con diagnóstico serológico confirmado para otras enfermedades bacterianas como brucelosis, leptospirosis, sífilis y Rickettsiosis. Se encontró una sensibilidad de 68,6% (IC95%: 58,2-79,0%, especificidad de 94,1% (86,7-100%, valor predictivo positivo de 95,2% (89,0-100% y valor predictivo negativo de 64,0% (54,3-71,2%, con una reacción cruzada con otras etiologías bacterianas de 78,1% (25/32. Esta no es una prueba idónea para ser usada como herramienta diagnóstica para la Enfermedad de Carrión, se debe continuar los estudios hacia la búsqueda de una prueba rápida con mayor sensibilidad.

Aspergillus fumigatus and other thermophilic fungi in nests of wetland birds.

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Korniłłowicz-Kowalska, Teresa; Kitowski, Ignacy

2013-02-01

A study was performed on the numbers and species diversity of thermophilic fungi (growing at 45 °C in vitro) in 38 nests of 9 species of wetland birds, taking into account the physicochemical properties of the nests and the bird species. It was found that in nests with the maximum weight (nests of Mute Swan), the number and diversity of thermophilic fungi were significantly greater than in other nests, with lower weight. The diversity of the thermophilic biota was positively correlated with the individual mass of bird and with the level of phosphorus in the nests. The dominant species within the mycobiota under study was Aspergillus fumigatus which inhabited 95% of the nests under study, with average frequency of ca. 650 cfu g(-1) of dry mass of the nest material. In a majority of the nests studied (nests of 7 bird species), the share of A. fumigatus exceeded 50% of the total fungi growing at 45 °C. Significantly higher frequencies of the fungal species were characteristic of the nests of small and medium-sized piscivorous species, compared with the other bird species. The number of A. fumigatus increased with increase in the moisture level of the nests, whereas the frequency of occurrence of that opportunistic pathogen, opposite to the general frequency of thermophilic mycobiota, was negatively correlated with the level of phosphorus in the nest material, and with the body mass and length of the birds. The authors indicate the causes of varied growth of thermophilic fungi in nests of wetland birds and, in particular, present a discussion of the causes of accumulation of A. fumigatus, the related threats to the birds, and its role as a source of transmission in the epidemiological chain of aspergillosis.

Differential effects of coyotes and red foxes on duck nest success

Science.gov (United States)

Sovada, Marsha A.; Sargeant, A.; Grier, J.W.

1995-01-01

Low recruitment rates prevail among ducks in the Prairie Pothole Region of North America, primarily because of high nest depredation rates. The red fox (Vulpes vulpes) is a major predator of duck eggs, but fox abundance is depressed by coyotes (Canis latrans). We tested the hypothesis that nest success of upland-nesting ducks is higher in areas with coyotes than in areas with red foxes. We conducted the study during 1990-92 in uplands of 36 areas managed for nesting ducks in North Dakota and South Dakota. Overall nest success averaged 32% (95% CI = 25-40) on 17 study areas where coyotes were the principal canid and 17% (CI = 11-25) on 13 study areas where red foxes were the principal canid (P = 0.01). Both canids were common on 6 other areas, where nest success averaged 25% (CI = 13-47). Habitat composition, predator communities with the exception of canids, and species composition of duck nests in coyote and red fox areas were similar overall. Upon examining only nests with greater than or equal to 6 eggs on the last visit prior to hatch or depredation, we determined nests with evidence characteristic of fox predation accounted for 4% of depredated nests in coyote areas and 27% in fox areas (P = 0.001). An expanding coyote population is contributing to higher overall nest success. Management of coyotes may be an effective method for increasing duck nest success.

Factors determining presence of passerines breeding within White Stork Ciconia ciconia nests

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Zbyryt, Adam; Jakubas, Dariusz; Tobolka, Marcin

2017-10-01

Nests of White Stork Ciconia ciconia are commonly used by various passerines as nesting sites. In this study, we investigated factors determining presence and number of pairs of species breeding within White Stork nests in an extensive farmland in NE Poland. In 133 (57%) out of 233 White Stork nests, we found at least one breeding pair of passerine bird. These were from three species: House Sparrows Passer domesticus (68% of 133 nests with co-breeding), Tree Sparrows Passer montanus (65%), and Starlings Sturnus vulgaris (30%). The probability of breeding passerines within White Stork nests increased with increasing nest thickness, and was significantly higher in currently occupied nests. Sparrows were more likely to breed in White Stork nests located on electricity poles, situated closer to settlements and surrounded mainly by arable fields where meadows were not prevalent. In this paper, we show that White Stork nests are favorable nesting sites for passerines, as they are well insulated and provide an anti-predatory shield.

Factors determining presence of passerines breeding within White Stork Ciconia ciconia nests.

Science.gov (United States)

Zbyryt, Adam; Jakubas, Dariusz; Tobolka, Marcin

2017-08-18

Nests of White Stork Ciconia ciconia are commonly used by various passerines as nesting sites. In this study, we investigated factors determining presence and number of pairs of species breeding within White Stork nests in an extensive farmland in NE Poland. In 133 (57%) out of 233 White Stork nests, we found at least one breeding pair of passerine bird. These were from three species: House Sparrows Passer domesticus (68% of 133 nests with co-breeding), Tree Sparrows Passer montanus (65%), and Starlings Sturnus vulgaris (30%). The probability of breeding passerines within White Stork nests increased with increasing nest thickness, and was significantly higher in currently occupied nests. Sparrows were more likely to breed in White Stork nests located on electricity poles, situated closer to settlements and surrounded mainly by arable fields where meadows were not prevalent. In this paper, we show that White Stork nests are favorable nesting sites for passerines, as they are well insulated and provide an anti-predatory shield.

Nesting habitat and productivity of Swainson's Hawks in southeastern Arizona

Science.gov (United States)

Nishida, Catherine; Boal, Clint W.; DeStefano, Stephen; Hobbs, Royden J.

2013-01-01

We studied Swainson's Hawks (Buteo swainsoni) in southeastern Arizona to assess the status of the local breeding population. Nest success (≥1 young fledged) was 44.4% in 1999 with an average of 1.43 ± 0.09 (SE) young produced per successful pair. Productivity was similar in 2000, with 58.2% nesting success and 1.83 ± 0.09 fledglings per successful pair. Mesquite (Prosopis velutina) and cottonwood (Populus fremontii) accounted for >50% of 167 nest trees. Nest trees were taller than surrounding trees and random trees, and overall there was more vegetative cover at nest sites than random sites. This apparent requirement for cover around nest sites could be important for management of the species in Arizona. However, any need for cover at nest sites must be balanced with the need for open areas for foraging. Density of nesting Swainson's Hawks was higher in agriculture than in grasslands and desert scrub. Breeding pairs had similar success in agricultural and nonagricultural areas, but the effect of rapid and widespread land-use change on breeding distribution and productivity continues to be a concern throughout the range of the species.

Rhode Island, Connecticut, New York, and New Jersey ESI: NESTS (Nest Points)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for nesting birds in coastal Rhode Island, Connecticut, New York, and New Jersey. Vector points in this...

Thermal fluctuation within nests and predicted sex ratio of Morelet's Crocodile.

Science.gov (United States)

Escobedo-Galván, Armando H; López-Luna, Marco A; Cupul-Magaña, Fabio G

2016-05-01

Understanding the interplay between thermal variations and sex ratio in reptiles with temperature-dependent sex determination is the first step for developing long-term conservation strategies. In case of crocodilians, the information is fragmentary and insufficient for establishing a general framework to consider how thermal fluctuation influence sex determination under natural conditions. The main goal of this study was to analyze thermal variation in nests of Crocodylus moreletii and to discuss the potential implications for predicting offspring sex ratio. The study was carried out at the Centro de Estudios Tecnológicos del Mar N° 2 and at the Sistemas Productivos Cocodrilo, Campeche, Mexico. Data was collected in the nesting season of Morelet's Crocodiles during three consecutive seasons (2007-2009). Thermal fluctuations for multiple areas of the nest chamber were registered by data loggers. We calculate the constant temperature equivalent based on thermal profiles among nests to assess whether there are differences between the nest temperature and its equivalent to constant temperature. We observed that mean nest temperature was only different among nests, while daily thermal fluctuations vary depending on the depth position within the nest chamber, years and nests. The constant temperature equivalent was different among and within nests, but not among survey years. We observed differences between constant temperature equivalent and mean nest temperature both at the top and in the middle of the nest cavities, but were not significantly different at the bottom of nest cavities. Our results enable examine and discuss the relevance of daily thermal fluctuations to predict sex ratio of the Morelet's Crocodile. Copyright © 2016 Elsevier Ltd. All rights reserved.

Linking snake behavior to nest predation in a Midwestern bird community.

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Weatherhead, Patrick J; Carfagno, Gerardo L F; Sperry, Jinelle H; Brawn, Jeffrey D; Robinson, Scott K

2010-01-01

Nest predators can adversely affect the viability of songbird populations, and their impact is exacerbated in fragmented habitats. Despite substantial research on this predator-prey interaction, however, almost all of the focus has been on the birds rather than their nest predators, thereby limiting our understanding of the factors that bring predators and nests into contact. We used radiotelemetry to document the activity of two snake species (rat snakes, Elaphe obsoleta; racers, Coluber constrictor) known to prey on nests in Midwestern bird communities and simultaneously monitored 300 songbird nests and tested the hypothesis that predation risk should increase for nests when snakes were more active and in edge habitat preferred by both snake species. Predation risk increased when rat snakes were more active, for all nests combined and for two of the six bird species for which we had sufficient nests to allow separate analyses. This result is consistent with rat snakes being more important nest predators than racers. We found no evidence, however, that nests closer to forest edges were at greater risk. These results are generally consistent with the one previous study that investigated rat snakes and nest predation simultaneously. The seemingly paradoxical failure to find higher predation risk in the snakes' preferred habitat (i.e., edge) might be explained by the snakes using edges at least in part for non-foraging activities. We propose that higher nest predation in fragmented habitats (at least that attributable to snakes) results indirectly from edges promoting larger snake populations, rather than from edges directly increasing the risk of nest predation by snakes. If so, the notion of edges per se functioning as ecological "traps" merits further study.

Predation risk of artificial ground nests in managed floodplain meadows

Science.gov (United States)

Arbeiter, Susanne; Franke, Elisabeth

2018-01-01

Nest predation highly determines the reproductive success in birds. In agricultural grasslands, vegetation characteristics and management practices influences the predation risk of ground breeders. Little is known so far on the predation pressure on non-passerine nests in tall swards. Investigations on the interaction of land use with nesting site conditions and the habitat selection of nest predators are crucial to develop effective conservation measures for grassland birds. In this study, we used artificial nests baited with quail and plasticine eggs to identify potential predators of ground nests in floodplain meadows and related predation risk to vegetation structure and grassland management. Mean daily predation rate was 0.01 (±0.012) after an exposure duration of 21 days. 70% of all observed nest predations were caused by mammals (Red Fox and mustelids) and 17.5% by avian predators (corvids). Nest sites close to the meadow edge and those providing low forb cover were faced with a higher daily predation risk. Predation risk also increased later in the season. Land use in the preceding year had a significant effect on predation risk, showing higher predation rates on unmanaged sites than on mown sites. Unused meadows probably attract mammalian predators, because they provide a high abundance of small rodents and a more favourable vegetation structure for foraging, increasing also the risk of incidental nest predations. Although mowing operation is a major threat to ground-nesting birds, our results suggest that an annual removal of vegetation may reduce predation risk in the subsequent year.

Local individual preferences for nest materials in a passerine bird.

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Adèle Mennerat

Full Text Available Variation in the behavioural repertoire of animals is acquired by learning in a range of animal species. In nest-building birds, the assemblage of nest materials in an appropriate structure is often typical of a bird genus or species. Yet plasticity in the selection of nest materials may be beneficial because the nature and abundance of nest materials vary across habitats. Such plasticity can be learned, either individually or socially. In Corsican populations of blue tits Cyanistes caeruleus, females regularly add in their nests fragments of several species of aromatic plants during the whole breeding period. The selected plants represent a small fraction of the species present in the environment and have positive effects on nestlings.We investigated spatiotemporal variations of this behaviour to test whether the aromatic plant species composition in nests depends on 1 plant availability in territories, 2 female experience or 3 female identity. Our results indicate that territory plays a very marginal role in the aromatic plant species composition of nests. Female experience is not related to a change in nest plant composition. Actually, this composition clearly depends on female identity, i.e. results from individual preferences which, furthermore, are repeatable both within and across years. A puzzling fact is the strong difference in plant species composition of nests across distinct study plots.This study demonstrates that plant species composition of nests results from individual preferences that are homogeneous within study plots. We propose several hypotheses to interpret this pattern of spatial variation before discussing them in the light of preliminary results. As a conclusion, we cannot exclude the possibility of social transmission of individual preferences for aromatic plants. This is an exciting perspective for further work in birds, where nest construction behaviour has classically been considered as a stereotypic behaviour.

Local individual preferences for nest materials in a passerine bird.

Science.gov (United States)

Mennerat, Adèle; Perret, Philippe; Lambrechts, Marcel M

2009-01-01

Variation in the behavioural repertoire of animals is acquired by learning in a range of animal species. In nest-building birds, the assemblage of nest materials in an appropriate structure is often typical of a bird genus or species. Yet plasticity in the selection of nest materials may be beneficial because the nature and abundance of nest materials vary across habitats. Such plasticity can be learned, either individually or socially. In Corsican populations of blue tits Cyanistes caeruleus, females regularly add in their nests fragments of several species of aromatic plants during the whole breeding period. The selected plants represent a small fraction of the species present in the environment and have positive effects on nestlings. We investigated spatiotemporal variations of this behaviour to test whether the aromatic plant species composition in nests depends on 1) plant availability in territories, 2) female experience or 3) female identity. Our results indicate that territory plays a very marginal role in the aromatic plant species composition of nests. Female experience is not related to a change in nest plant composition. Actually, this composition clearly depends on female identity, i.e. results from individual preferences which, furthermore, are repeatable both within and across years. A puzzling fact is the strong difference in plant species composition of nests across distinct study plots. This study demonstrates that plant species composition of nests results from individual preferences that are homogeneous within study plots. We propose several hypotheses to interpret this pattern of spatial variation before discussing them in the light of preliminary results. As a conclusion, we cannot exclude the possibility of social transmission of individual preferences for aromatic plants. This is an exciting perspective for further work in birds, where nest construction behaviour has classically been considered as a stereotypic behaviour.

Arctic foxes, lemmings, and canada goose nest survival at cape Churchill, Manitoba

Science.gov (United States)

Reiter, M.E.; Andersen, D.E.

2011-01-01

We examined factors influencing Canada Goose (Branta canadensis interior) annual nest success, including the relative abundance of collared lemmings (Dicrostonyx richardsoni), arctic fox (Alopex lagopus) den occupancy, nest density, and spring phenology using data collected during annual Canada Goose breeding area surveys at Cape Churchill, Manitoba. Nest density and arctic fox den occupancy strongly influenced Canada Goose nest success. High nest density resulted in higher nest success and high den occupancy reduced nest success. Nest success was not influenced by lemming abundance in the current or previous year as predicted by the "bird-lemming" hypothesis. Reducing arctic fox abundance through targeted management increased nest survival of Canada Geese; a result that further emphasizes the importance of arctic fox as nest predators in this system. The spatial distribution of nest predators, at least for dispersed-nesting geese, may be most important for nest survival, regardless of the abundance of small mammals in the local ecosystem. Further understanding of the factors influencing the magnitude and variance in arctic fox abundance in this region, and the spatial scale at which these factors are realized, is necessary to fully explain predator-prey-alternative prey dynamics in this system. ?? 2011 by the Wilson Ornithological Society.

Soil attributes drive nest-site selection by the campo miner Geositta poeciloptera

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Teixeira, João Paulo Gusmão; Solar, Ricardo; Vasconcelos, Bruno Nery F.; Fernandes, Raphael B. A.; Lopes, Leonardo Esteves

2018-01-01

Substrate type is a key-factor in nest-site selection and nest architecture of burrowing birds. However, little is known about which factors drive nest-site selection for these species, especially in the tropics. We studied the influence of soil attributes on nest-site selection by the campo miner Geositta poeciloptera, an open grassland bird that builds its nests within soil cavities. For all nests found, we measured the depth of the nest cavity and the resistance of the soil to penetration, and identified the soil horizon in which the nest was located. In soil banks with nests, we collected soil samples for granulometric analysis around each nest cavity, while in soil banks without nests we collected these samples at random points. From 43 nests found, 86% were located in the deeper soil horizons (C-horizon), and only 14% in the shallower horizons (B-horizon). Granulometric analysis showed that the C-horizons possessed a high similar granulometric composition, with high silt and low clay contents. These characteristics are associated with a low degree of structural development of the soil, which makes it easier to excavate. Contrarily, soil resistance to penetration does not seem to be an important criterion for nest site selection, although nests in more resistant the soils tend to have shallower nest cavities. Among the soil banks analyzed, 40% of those without cavities possessed a larger proportion of B-horizon relative to the C-horizon, and their texture was more clayey. On the other hand, almost all soil banks containing nest cavities had a larger C-horizon and a silty texture, indicating that soil attributes drive nest-site selection by G. poeciloptera. Thus, we conclude that the patchy distribution of G. poeciloptera can attributed to the infrequent natural exposure of the C-horizon in the tropical region, where well developed, deep and permeable soils are more common. PMID:29381768

Soil attributes drive nest-site selection by the campo miner Geositta poeciloptera.

Science.gov (United States)

Meireles, Ricardo Camargos de; Teixeira, João Paulo Gusmão; Solar, Ricardo; Vasconcelos, Bruno Nery F; Fernandes, Raphael B A; Lopes, Leonardo Esteves

2018-01-01

Substrate type is a key-factor in nest-site selection and nest architecture of burrowing birds. However, little is known about which factors drive nest-site selection for these species, especially in the tropics. We studied the influence of soil attributes on nest-site selection by the campo miner Geositta poeciloptera, an open grassland bird that builds its nests within soil cavities. For all nests found, we measured the depth of the nest cavity and the resistance of the soil to penetration, and identified the soil horizon in which the nest was located. In soil banks with nests, we collected soil samples for granulometric analysis around each nest cavity, while in soil banks without nests we collected these samples at random points. From 43 nests found, 86% were located in the deeper soil horizons (C-horizon), and only 14% in the shallower horizons (B-horizon). Granulometric analysis showed that the C-horizons possessed a high similar granulometric composition, with high silt and low clay contents. These characteristics are associated with a low degree of structural development of the soil, which makes it easier to excavate. Contrarily, soil resistance to penetration does not seem to be an important criterion for nest site selection, although nests in more resistant the soils tend to have shallower nest cavities. Among the soil banks analyzed, 40% of those without cavities possessed a larger proportion of B-horizon relative to the C-horizon, and their texture was more clayey. On the other hand, almost all soil banks containing nest cavities had a larger C-horizon and a silty texture, indicating that soil attributes drive nest-site selection by G. poeciloptera. Thus, we conclude that the patchy distribution of G. poeciloptera can attributed to the infrequent natural exposure of the C-horizon in the tropical region, where well developed, deep and permeable soils are more common.

Nesting Ecology of Hawksbill Sea Turtles (Eretmochelys imbricata) on Utila, Honduras

Science.gov (United States)

Damazo, Lindsey Renee Eggers

The hawksbill sea turtle (Eretmochelys imbricata) has a circumtropical distribution and plays an important role in maintaining the health of coral reefs. Unfortunately, hawksbill populations have been decimated, and estimated numbers in the Caribbean are less than 10% of populations a century ago. The hawksbill is considered Critically Endangered, and researchers are coordinating worldwide efforts to protect this species. One country where we lack knowledge regarding hawksbills is Honduras. This study aimed to increase our understanding of hawksbill nesting ecology in Caribbean Honduras. Characteristics of hawksbill nesting activity and a nesting beach on the island of Utila were elucidated using satellite telemetry, beach profiling, vegetation surveys, beach monitoring, and nest temperature profiles. We affixed satellite transmitters to two nesting hawksbills, and found the turtles migrated to different countries. One turtle traveled 403 km to a bay in Mexico, and the other traveled 181 km to a Marine Protected Area off Belize. This study presents the first description of hawksbill migration routes from Honduras, facilitating protection efforts for turtles that traverse international waters. To investigate nesting beach and turtle characteristics, we conducted beach monitoring during the 2012 nesting season. Nesting turtle carapace sizes were similar to worldwide values, but hatchlings were heavier. To measure nest temperatures, we placed thermocouple data loggers in four nests and four pseudo-nests. Data suggested metabolic heating may be maintaining nest temperatures above the pivotal temperature. However, large temperature fluctuations corresponding to rainfall from Hurricane Ernesto (as determined using a time series cross-correlation analysis) make it difficult to predict sex ratios, and underscore the impact stochastic events can have on nest temperatures. We created topographic and substrate profiles of the beach, and found it was 475 m long, yet hawksbills

Nesting behaviour influences species-specific gas exchange across avian eggshells.

Science.gov (United States)

Portugal, Steven J; Maurer, Golo; Thomas, Gavin H; Hauber, Mark E; Grim, Tomáš; Cassey, Phillip

2014-09-15

Carefully controlled gas exchange across the eggshell is essential for the development of the avian embryo. Water vapour conductance (G(H2O)) across the shell, typically measured as mass loss during incubation, has been demonstrated to optimally ensure the healthy development of the embryo while avoiding desiccation. Accordingly, eggs exposed to sub-optimal gas exchange have reduced hatching success. We tested the association between eggshell G(H2O) and putative life-history correlates of adult birds, ecological nest parameters and physical characteristics of the egg itself to investigate how variation in G(H2O) has evolved to maintain optimal water loss across a diverse set of nest environments. We measured gas exchange through eggshell fragments in 151 British breeding bird species and fitted phylogenetically controlled, general linear models to test the relationship between G(H2O) and potential predictor parameters of each species. Of our 17 life-history traits, only two were retained in the final model: wet-incubating parent and nest type. Eggs of species where the parent habitually returned to the nest with wet plumage had significantly higher G(H2O) than those of parents that returned to the nest with dry plumage. Eggs of species nesting in ground burrows, cliffs and arboreal cups had significantly higher G(H2O) than those of species nesting on the ground in open nests or cups, in tree cavities and in shallow arboreal nests. Phylogenetic signal (measured as Pagel's λ) was intermediate in magnitude, suggesting that differences observed in the G(H2O) are dependent upon a combination of shared ancestry and species-specific life history and ecological traits. Although these data are correlational by nature, they are consistent with the hypothesis that parents constrained to return to the nest with wet plumage will increase the humidity of the nest environment, and the eggs of these species have evolved a higher G(H2O) to overcome this constraint and still

Evidencias iniciales de validez de criterio de los resultados de una Prueba de razonamiento con figuras para la selección de estudiantes indígenas para la Universidad de Costa Rica y el Instituto Tecnológico de Costa Rica

Directory of Open Access Journals (Sweden)

Eiliana Montero-Rojas

2013-01-01

Full Text Available Se presentan los resultados parciales de un proyecto de investigación mediante el cual se estudia la posibilidad de utilizar algunas pruebas psicométricas, distintas a las utilizadas actualmente para el proceso de admisión en la Universidad de Costa Rica y del Instituto Tecnológico de Costa Rica, como parte de un proceso de selección específica para jóvenes indígenas con potencial académico para cursar estudios universitarios. Se comparan los resultados obtenidos por estudiantes de último año de tres colegios indígenas en la llamada Prueba de razonamiento con figuras (PRF, con los obtenidos en las Pruebas de admisión mencionadas. Se encontraron evidencias de correlación entre la PRF con cada una de las Pruebas de admisión, lo que muestra un nivel aceptable de asociación entre los constructos medidos por las mismas. Asimismo, las pruebas pareadas de diferencias de promedios con población no indígena que aplicó los mismos tests en el 2008, mostraron una diferencia significa a favor de la PRF en comparación con cada una de las Pruebas de admisión. Esta es una primera evidencia que apoya la validez de criterio de esta prueba en el contexto de su aplicación como posible instrumento de selección complementario para ingreso a las universidades en este grupo de población.

Introducción de pruebas rápidas para sífilis y VIH en el control prenatal en Colombia: análisis cualitativo

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María Teresa Ochoa-Manjarrés

Full Text Available RESUMEN Objetivo Interpretar la percepción de profesionales sanitarios de Colombia sobre las barreras y los facilitadores para la introducción de las pruebas rápidas para sífilis y virus de la inmunodeficiencia humana (VIH en los servicios de control prenatal. Métodos Se aplicó una metodología cualitativa basada en entrevistas semiestructuradas. Se seleccionó una muestra de conveniencia de 37 participantes, que incluyó profesionales sanitarios vinculados a servicios de control prenatal, programas para gestantes, laboratorios clínicos y directores de unidades o centros asistenciales, así como representantes de las direcciones territoriales y del Ministerio de Salud y Protección Social. Resultados En Colombia no hay un uso generalizado del tamizaje con pruebas rápidas para sífilis y VIH en el control prenatal. Los entrevistados manifestaron no tener experiencia previa en el uso de pruebas rápidas —excepto el personal de laboratorio— y sobre el curso de acción ante un resultado positivo. El sistema de aseguramiento de salud dificulta el acceso al diagnóstico y el tratamiento oportunos. Las autoridades de salud perciben como necesaria la revisión de la normativa existente, a fin de fortalecer el primer nivel de atención y promover el control prenatal integral. Los participantes recomendaron la capacitación del personal y la integración entre instancias de formulación de políticas de salud y académicas para actualizar los currículos de formación. Conclusiones El enfoque de mercado y las características del sistema de salud colombiano constituyen la principal barrera para la implementación de las pruebas rápidas como estrategia para la eliminación de la transmisión materno-infantil de sífilis y VIH. Entre las medidas identificadas están: realizar cambios en la contratación entre las aseguradoras y las instituciones prestadoras de servicios, adecuar los tiempos y la organización de los procedimientos de atenci

Nesting bird "host funnel" increases mosquito-bird contact rate.

Science.gov (United States)

Caillouët, Kevin A; Riggan, Anna E; Bulluck, Lesley P; Carlson, John C; Sabo, Roy T

2013-03-01

Increases in vector-host contact rates can enhance arbovirus transmission intensity. We investigated weekly fluctuations in contact rates between mosquitoes and nesting birds using the recently described Nest Mosquito Trap (NMT). The number of mosquitoes per nestling increased from nesting season. Our evidence suggests the coincidence of the end of the avian nesting season and increasing mosquito abundances may have caused a "host funnel," concentrating host-seeking mosquitoes to the few remaining nestlings. The relative abundance of mosquitoes collected by the NMT suggests that significantly more Aedes albopictus (Skuse) and Culex pipiens (L.) /restuans (Theobald) sought nesting bird bloodmeals than were predicted by their relative abundances in CO2-baited Centers for Disease Control and Prevention light and gravid traps. Culex salinarius (Coquillett) and Culex erraticus Dyar and Knab were collected in NMTs in proportion to their relative abundances in the generic traps. Temporal host funnels and nesting bird host specificity may enhance arbovirus amplification and explain observed West Nile virus and St. Louis encephalitis virus amplification periods.

Birds' nesting parameters in four forest types in the Pantanal wetland

Directory of Open Access Journals (Sweden)

JB Pinho

Full Text Available We tested the heterogeneity/productivity hypothesis with respect to the abundance and richness of birds and the vegetation density hypothesis with respect to birds' nest predation rates, and determined the relative importance of forested vegetation formations for the conservation of birds in the Pantanal. We estimated the apparent nesting success, and the abundance and richness of nesting birds' in four forest types, by monitoring nests during two reproductive seasons in four forested physiognomies (two high productivity/heterogeneity evergreen forests = Cambará and Landi; two low productivity/heterogeneity dry forests = Cordilheira and Carvoeiro in the Pantanal wetland in Poconé, State of Mato Grosso, Brazil. We found 381 nests of 46 species (35 Passeriformes and 11 non-Passeriformes in the four forest types. Of these, we monitored 220 active nests belonging to 44 species, 101 during the reproductive season of 2001 and 119 in 2002. We supported the productivity/heterogeneity hypothesis since the two evergreen forests had higher nest abundance and one of them (Cambará had higher nesting species richness than the dry forests. The number of nests found in each habitat differed with most nests monitored in the Cambará forest (82%, followed by Landi (9%, Cordilheira (6% and Carvoeiro (3% forests. The total number of nests monitored was significantly higher in evergreen forests than in dry forests. Also, more species nested in evergreen (37 species than in dry (16 species forests. A Correspondence Analysis revealed that only Carvoeiros had a different nesting bird community. The overall apparent nesting success of 220 nests was 26.8%. We did not support the vegetation density hypothesis since nest predation rates were similar between evergreen (73.5% and dry (70% forests, and were higher in the Landi (85% than in the other three forests (69.2 to 72.2%. Our data indicate that Cambará forests seem to be a key nesting habitat for many bird species

Birds' nesting parameters in four forest types in the Pantanal wetland.

Science.gov (United States)

Pinho, J B; Marini, M A

2014-11-01

We tested the heterogeneity/productivity hypothesis with respect to the abundance and richness of birds and the vegetation density hypothesis with respect to birds' nest predation rates, and determined the relative importance of forested vegetation formations for the conservation of birds in the Pantanal. We estimated the apparent nesting success, and the abundance and richness of nesting birds' in four forest types, by monitoring nests during two reproductive seasons in four forested physiognomies (two high productivity/heterogeneity evergreen forests = Cambará and Landi; two low productivity/heterogeneity dry forests = Cordilheira and Carvoeiro) in the Pantanal wetland in Poconé, State of Mato Grosso, Brazil. We found 381 nests of 46 species (35 Passeriformes and 11 non-Passeriformes) in the four forest types. Of these, we monitored 220 active nests belonging to 44 species, 101 during the reproductive season of 2001 and 119 in 2002. We supported the productivity/heterogeneity hypothesis since the two evergreen forests had higher nest abundance and one of them (Cambará) had higher nesting species richness than the dry forests. The number of nests found in each habitat differed with most nests monitored in the Cambará forest (82%), followed by Landi (9%), Cordilheira (6%) and Carvoeiro (3%) forests. The total number of nests monitored was significantly higher in evergreen forests than in dry forests. Also, more species nested in evergreen (37 species) than in dry (16 species) forests. A Correspondence Analysis revealed that only Carvoeiros had a different nesting bird community. The overall apparent nesting success of 220 nests was 26.8%. We did not support the vegetation density hypothesis since nest predation rates were similar between evergreen (73.5%) and dry (70%) forests, and were higher in the Landi (85%) than in the other three forests (69.2 to 72.2%). Our data indicate that Cambará forests seem to be a key nesting habitat for many bird species of the

Methods for excluding cliff swallows from nesting on highway structures.

Science.gov (United States)

2009-08-01

Cliff swallows (Petrochelidon pyrrhonota) are colonially breeding migratory birds that frequently nest on highway : structures. Protected by the Migratory Bird Treaty Act of 1918, nesting control methods cannot harm swallows or active : nests. This c...

Motivación de la prueba, Hechos e Inaplicación de los Métodos de Valoración, que afectan el debido proceso en sentencias de la Corte Superior de Justicia de Puno, 2013 - 2014

OpenAIRE

Chura Perez, Olga Madelaine

2015-01-01

La presente investigación tuvo como: objetivo general, verificar que la carencia de motivación en la valoración de la prueba, los hechos e inaplicación de los métodos de la valoración de la prueba como causas que afectan el derecho al debido proceso, en las sentencias condenatorias en materia penal de la zona norte de la Corte Superior de Justicia de Puno 2013 – 2014. Como objetivos específicos: a) Determinar que la carencia de motivación en la valoración de la prueba es una...

Diseño de un modelo de supervisión para la aplicación de la prueba de Evaluación del Desarrollo Infantil en las unidades de atención primaria en México

OpenAIRE

Villasís-Keever, Miguel Ángel; Rizzoli-Córdoba, Antonio; Delgado-Ginebra, Ismael; Mares-Serratos, Blanca Berenice; Martell-Valdez, Liliana; Sánchez-Velázquez, Olivia; Reyes-Morales, Hortensia; O'Shea-Cuevas, Gabriel; Aceves-Villagrán, Daniel; Carrasco-Mendoza, Joaquín; Antillón-Ocampo, Fátima Adriana; Villagrán-Muñoz, Víctor Manuel; Halley-Castillo, Elizabeth; Baqueiro-Hernández, César Iván; Pizarro-Castellanos, Mariel

2015-01-01

Introducción: La prueba Evaluación del Desarrollo Infantil (EDI), diseñada y validada en México, se ha aplicado en las unidades de atención primaria del país. Los resultados han sido heterogéneos entre los estados en que se aplicaron las pruebas, a pesar de haber utilizado un modelo de capacitación estandarizado con la misma metodología para la aplicación. El objetivo de este trabajo fue evaluar un modelo de supervisión que permita identificar la calidad de la aplicación de la prueba EDI a ni...

Effects of prescribed burns on wintering cavity-nesting birds

Science.gov (United States)

Heather L. Bateman; Margaret A. O' Connell

2006-01-01

Primary cavity-nesting birds play a critical role in forest ecosystems by excavating cavities later used by other birds and mammals as nesting or roosting sites. Several species of cavity-nesting birds are non-migratory residents and consequently subject to winter conditions. We conducted winter bird counts from 1998 to 2000 to examine the abundance and habitat...

Variation in nesting behavior of eight species of spider mites, Stigmaeopsis having sociality

Science.gov (United States)

Saito, Yutaka; Zhang, Yan-Xuan; Mori, Kotaro; Ito, Katsura; Sato, Yukie; Chittenden, Anthony R.; Lin, Jian-Zhen; Chae, Younghae; Sakagami, Takane; Sahara, Ken

2016-10-01

Nesting behavior is considered to be an important element of social living in animals. The spider mites belonging to the genus Stigmaeopsis spend their lives within nests produced from silk threads. Several of these species show cooperative sociality, while the others are subsocial. In order to identify the origins of this social behavior, comparisons of nest sizes, nesting behaviors (making nests continuously or separately), and their associated traits (fecal deposition patterns) were made for eight cogeneric Stigmaeopsis species showing various levels of social development. All of these species inhabit bamboo plants (Poaceae). We initially addressed the proximate factor of nest size variation. The variation in nest size of the eight species corresponded well with the variation in dorsal seta sc1 length, suggesting that nest size variation among species may have a genetic basis. The time spent within a nest (nest duration) increased with nest size on the respective host plants. Nest arrangement patterns varied among species showing different sized nests: Large nest builders continuously extended their nests, while middle and small nest-building species built new separate nests, which resulted in different social interaction times among species, and is thought to be closely related to social development. Fecal deposition behaviors also varied among Stigmaeopsis species, suggesting diversity in anti-predatory adaptations. Finally, we discuss how the variation in sociality observed within this genus is likely the result of nest size variation that initially evolved as anti-predator strategies.

Determinación de necesidades nutrimentales para las especies Swietenia macrophylla y Cupressus lusitanica en prueba de invernadero

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A. Paniagua Vásquez

2004-01-01

Full Text Available Se determinaron los requerimientos nutrimentales de Swietenia macrophylla y Cupressus lusitanica en un Inceptisol y Ultisol provenientes de la región Huetar Norte de Costa Rica, en una prueba de invernadero utilizando una metodología que involucra tres pasos fundamentales: a análisis preliminar de la muestra original, b estudios de Sorción, c técnicas de invernadero. La muestra del suelo se recolectó en sitios representativos a una profundidad de 0-25 cm. En Inceptisol los requerimentos para Sweitenia macrophylla en orden según las pruebas de invernadero fueron: P> Cu> B> Fe> N, para Cupressus lusitanica fueron: P> K> Mn> Cu> Zn> Fe. En Ultisol los requerimentos nutrimentales para Sweitenia macrophylla fueron: B> Fe> Mn> Zn> N> P> K> Cu. Es importante considerar que son los elementos menores los que tienen mayor respuesta a la aplicación, con las variables de crecimiento los mayores valores se obtuvieron en orden K> N> P, para Cupressus lusitanica resultados fueron: N> P> Mn> Fe> Zn. Con las variables de crecimiento los mayores valores se obtuvieron en orden K> N> P.

Variation in clutch size in relation to nest size in birds

NARCIS (Netherlands)

Møller, Anders P.; Adriaensen, Frank; Artemyev, Alexandr; Bańbura, Jerzy; Barba, Emilio; Biard, Clotilde; Blondel, Jacques; Bouslama, Zihad; Bouvier, Jean-Charles; Camprodon, Jordi; Cecere, Francesco; Charmantier, Anne; Charter, Motti; Cichoń, Mariusz; Cusimano, Camillo; Czeszczewik, Dorota; Demeyrier, Virginie; Doligez, Blandine; Doutrelant, Claire; Dubiec, Anna; Eens, Marcel; Eeva, Tapio; Faivre, Bruno; Ferns, Peter N.; Forsman, Jukka T.; García-Del-Rey, Eduardo; Goldshtein, Aya; Goodenough, Anne E.; Gosler, Andrew G.; Góźdź, Iga; Grégoire, Arnaud; Gustafsson, Lars; Hartley, Ian R.; Heeb, Philipp; Hinsley, Shelley A.; Isenmann, Paul; Jacob, Staffan; Järvinen, Antero; Juškaitis, Rimvydas; Korpimäki, Erkki; Krams, Indrikis; Laaksonen, Toni; Leclercq, Bernard; Lehikoinen, Esa; Loukola, Olli; Lundberg, Arne; Mainwaring, Mark C.; Mänd, Raivo; Massa, Bruno; Mazgajski, Tomasz D.; Merino, Santiago; Mitrus, Cezary; Mönkkönen, Mikko; Morales-Fernaz, Judith; Morin, Xavier; Nager, Ruedi G.; Nilsson, Jan-Åke; Nilsson, Sven G.; Norte, Ana C.; Orell, Markku; Perret, Philippe; Pimentel, Carla S.; Pinxten, Rianne; Priedniece, Ilze; Quidoz, Marie-Claude; Remeš, Vladimir; Richner, Heinz; Robles, Hugo; Rytkönen, Seppo; Senar, Juan Carlos; Seppänen, Janne T.; da Silva, Luís P.; Slagsvold, Tore; Solonen, Tapio; Sorace, Alberto; Stenning, Martyn J.; Török, János; Tryjanowski, Piotr; van Noordwijk, Arie J.; von Numers, Mikael; Walankiewicz, Wiesław; Lambrechts, Marcel M.

2014-01-01

Nests are structures built to support and protect eggs and/or offspring from predators, parasites, and adverse weather conditions. Nests are mainly constructed prior to egg laying, meaning that parent birds must make decisions about nest site choice and nest building behavior before the start of

Phenology largely explains taller grass at successful nests in greater sage-grouse.

Science.gov (United States)

Smith, Joseph T; Tack, Jason D; Doherty, Kevin E; Allred, Brady W; Maestas, Jeremy D; Berkeley, Lorelle I; Dettenmaier, Seth J; Messmer, Terry A; Naugle, David E

2018-01-01

Much interest lies in the identification of manageable habitat variables that affect key vital rates for species of concern. For ground-nesting birds, vegetation surrounding the nest may play an important role in mediating nest success by providing concealment from predators. Height of grasses surrounding the nest is thought to be a driver of nest survival in greater sage-grouse ( Centrocercus urophasianus ; sage-grouse), a species that has experienced widespread population declines throughout their range. However, a growing body of the literature has found that widely used field methods can produce misleading inference on the relationship between grass height and nest success. Specifically, it has been demonstrated that measuring concealment following nest fate (failure or hatch) introduces a temporal bias whereby successful nests are measured later in the season, on average, than failed nests. This sampling bias can produce inference suggesting a positive effect of grass height on nest survival, though the relationship arises due to the confounding effect of plant phenology, not an effect on predation risk. To test the generality of this finding for sage-grouse, we reanalyzed existing datasets comprising >800 sage-grouse nests from three independent studies across the range where there was a positive relationship found between grass height and nest survival, including two using methods now known to be biased. Correcting for phenology produced equivocal relationships between grass height and sage-grouse nest survival. Viewed in total, evidence for a ubiquitous biological effect of grass height on sage-grouse nest success across time and space is lacking. In light of these findings, a reevaluation of land management guidelines emphasizing specific grass height targets to promote nest success may be merited.

Red-shouldered hawk nesting habitat preference in south Texas

Science.gov (United States)

Strobel, Bradley N.; Boal, Clint W.

2010-01-01

We examined nesting habitat preference by red-shouldered hawks Buteo lineatus using conditional logistic regression on characteristics measured at 27 occupied nest sites and 68 unused sites in 2005–2009 in south Texas. We measured vegetation characteristics of individual trees (nest trees and unused trees) and corresponding 0.04-ha plots. We evaluated the importance of tree and plot characteristics to nesting habitat selection by comparing a priori tree-specific and plot-specific models using Akaike's information criterion. Models with only plot variables carried 14% more weight than models with only center tree variables. The model-averaged odds ratios indicated red-shouldered hawks selected to nest in taller trees and in areas with higher average diameter at breast height than randomly available within the forest stand. Relative to randomly selected areas, each 1-m increase in nest tree height and 1-cm increase in the plot average diameter at breast height increased the probability of selection by 85% and 10%, respectively. Our results indicate that red-shouldered hawks select nesting habitat based on vegetation characteristics of individual trees as well as the 0.04-ha area surrounding the tree. Our results indicate forest management practices resulting in tall forest stands with large average diameter at breast height would benefit red-shouldered hawks in south Texas.

Excepciones a la prueba prohibida para garantizar el derecho al debido proceso penal, en la Corte Superior de Justicia del Distrito Judicial de Huánuco, 2014 - 2015

OpenAIRE

Flores León, Vilma Felicitas

2016-01-01

La presente investigación ha tenido el objetivo de identificar las excepciones a la prueba prohibida que deben ser admitidas y valoradas para garantizar el derecho al debido proceso penal en la Corte Superior de Justicia del Distrito Judicial de Huánuco, 2014 - 2015, planteándose como una hipótesis que, la investigación de la verdad en el proceso penal, la defensa de los derechos fundamentales de la persona humana y el interés público, son las excepciones a la prueba prohibida que deben ser a...

Modificaciones en la composición corporal después de realizar una prueba de ultrarresistencia de 1.700 km en bicicleta de montaña

Directory of Open Access Journals (Sweden)

Vicente Clemente Suárez

2010-01-01

Full Text Available El estudio de los cambios en la composición corporal en pruebas de resistencia se ha limitado en la mayoría de los casos al estudio de las pérdidas de peso corporal. El presente estudio pretende analizar los cambios producidos en la composición corporal (agua, proteínas, minerales, grasa, y músculo producidos después de realizar una prueba de 1.700 Km en bicicleta de montaña cruzando África de este a oeste. Se analizaron 5 sujetos (73,3±10,2 kg, 170±0,1 cm, 51,2±6,9 años antes y después de realizar una prueba de ultrarresistencia en bicicleta de montaña de 1.700 km durante 17 días (100-110 km por etapa. Se analizaron los siguientes parámetros: Masa Agua Intracelular, Masa Agua Extracelular, Proteínas, Masa Mineral, Masa Grasa Corporal, Agua Corporal Total, Masa Músculo Esquelético, Masa Libre de Grasa, Peso y Área Grasa Visceral mediante bioimpedancia eléctrica (BIA con el analizador INBODY 720. Los resultados muestran una disminución no significativa de los parámetros de peso corporal y masa grasa, una disminución significativa en el área de grasa visceral (p>0,05. El resto de parámetros se mantuvieron en valores cercanos a la toma inicial. En conclusión este tipo de pruebas de ultrarresistencia únicamente afecta a los parámetros de grasa visceral, manteniendo el resto de variables de composición corporal sin cambios significativos.

Effects of nest density, location, and timing on breeding success of Caspian Terns

Science.gov (United States)

Antolos, Michelle; Roby, D.D.; Lyons, Donald E.; Anderson, Scott K.; Collis, K.

2006-01-01

One of the proposed benefits of colonial nesting in birds is the protection afforded against avian predators. This advantage may be counter-balanced by the negative effects of intraspecific aggression on breeding success. Effects of nest density, nest location within the colony, and timing of nest initiation on productivity of Caspian Terns (Sterna caspia) were investigated on Crescent Island in the mid-Columbia River, Washington, USA. In the absence of intense nest predation at the Crescent Island tern colony, it was hypothesized that nest density would be negatively associated with productivity. A rangefinder was used to determine spatial distribution of Caspian Tern nests, and these data used to calculate nest characteristics (nest density, nearest neighbor distance, and distance to colony edge) for a randomly-selected subset of nests monitored for nest chronology and productivity. Productivity did not differ between nests in high- and low-density areas of the colony, and was positively associated with earlier nest initiation. Early nests were more productive, were located in areas of higher nest density, and were further from the colony edge than late nests. The strong effect of timing may have been attributable to seasonal declines in prey resources for terns at this site. Our results suggest that Caspian Terns nesting at the highest densities observed in this study did not incur immediate reproductive costs, despite increased potential for encounters between chicks and aggressive conspecific adults.

Análisis de Tensiones mediante Elementos Finitos de una Válvula Esférica durante la Prueba Hidrostática, y su Verificación Experimental

OpenAIRE

Gualda, Néstor J; Sanzi, Héctor C; Ortiz, Luis

2010-01-01

En este trabajo se presenta el análisis de tensiones y deformaciones en el cuerpo de una válvula esférica de diámetro 8" serie 600, durante la prueba hidrostática, utilizando el método de elementos finitos. Se verifica el modelo con datos experimentales de tensiones, utilizando indicadores de deformación SG (Strain Gauges). Para el análisis mediante el método de elementos finitos se utilizó el programa Cosmos/M e información obtenida durante el análisis experimental. Las pruebas experimentale...

Bird nesting and droppings control on highway structures.

Science.gov (United States)

2010-10-01

This report provides a comprehensive literature survey of permanent and temporary deterrents to nesting and roosting, a : discussion of risks to human health and safety from exposure to bird nests and droppings and recommended protective measures, : ...

Prueba del software: más que una fase en el ciclo de vida/Software testing: more than a stage in the life cycle

Directory of Open Access Journals (Sweden)

Edgar Serna

2011-12-01

Full Text Available La prueba de software es probablemente la parte menos comprendida del ciclo de vida del desarrollo de software. En este trabajo, mediante una propuesta metodológica de cuatro fases, se muestra por qué es difícil detectar y eliminar errores, por qué es complejo el proceso de realizar pruebas y por qué es necesario prestarle más atención.Software testing probably is the least understood part of the software testing life cycle. In this work, by means of a methodological proposal of four stages, is showed why is complex the process of carrying out the testing software, why is necessary to pay it more attention and why is so difficult to detect and delete the mistakes.

Contrasting nest survival patterns for ducks and songbirds in northern mixed-grass prairie

Science.gov (United States)

Grant, Todd; Shaffer, Terry L.; Madden, Elizabeth M.; Nenneman, Melvin P.

2017-01-01

Management actions intended to protect or improve habitat for ducks may benefit grassland-nesting passerines, but scant information is available to explore this assumption. During 1998–2003, we examined nest survival of ducks and songbirds to determine whether effects of prescribed fire and other habitat features (e.g., shrub cover and distance to habitat edges) were similar for ducks and passerines breeding in North Dakota. We used the logistic-exposure method to estimate survival of duck and songbird nests (n = 3,171). We used an information-theoretic approach to identify factors that most influenced nest survival. Patterns of nest survival were markedly different between taxonomic groups. For ducks, nest survival was greater during the first postfire nesting season (daily survival rate [DSR] = 0.957, 85% CI = 0.951–0.963), relative to later postfire nesting seasons (DSR = 0.946, 85% CI = 0.942–0.950). Furthermore duck nest survival and nest densities were inversely related. Duck nest survival also was greater as shrub cover decreased and as distance from cropland and wetland edges increased. Passerines had lower nest survival during the first postfire nesting season (DSR = 0.934, 85% CI = 0.924–0.944), when densities also were low compared to subsequent postfire nesting seasons (DSR = 0.947, 85% CI = 0.944–0.950). Parasitism by brown-headed cowbirds (Molothrus ater) reduced passerine nest survival and this effect was more pronounced during the first postfire nesting season compared to subsequent nesting seasons. Passerine nest survival was greater as shrub cover decreased and perhaps for more concealed nests. Duck and songbird nest survival rates were not correlated during this study and for associated studies that examined additional variables using the same dataset, suggesting that different mechanisms influenced their survival. Based on our results, ducks should not be considered direct surrogates for passerines

Modificaciones en la composición corporal después de realizar una prueba de ultrarresistencia de 1.700 km en bicicleta de montaña

OpenAIRE

Clemente Suárez, Vicente J.; González-Ravé, José María

2010-01-01

El estudio de los cambios en la composición corporal en pruebas de resistencia se ha limitado en la mayoría de los casos al estudio de las pérdidas de peso corporal. El presente estudio pretende analizar los cambios producidos en la composición corporal (agua, proteínas, minerales, grasa, y músculo) producidos después de realizar una prueba de 1.700 Km en bicicleta de montaña cruzando África de este a oeste. Se analizaron 5 sujetos (73,3±10,2 kg, 170±0,1 cm, 51,2±6,9 a...

Cavity-nesting bird abundance in thinned versus unthinned Massachusetts oak stands

Science.gov (United States)

Christopher J.E. Welsh; William M. Healy; Richard M. DeGraaf

1992-01-01

Cavity-nesting birds provide significant benefits to forest communities, but timber management techniques may negatively affect cavity-nesting species by reducing the availability of suitable nest and foraging sites. We surveyed cavity-nesting birds from transects in eight Massachusetts oak stands to examine the effect of thinning with retention of snag and wildlife...

A unique nest-protection strategy in a new species of spider wasp.

Directory of Open Access Journals (Sweden)

Michael Staab

Full Text Available Hymenoptera show a great variation in reproductive potential and nesting behavior, from thousands of eggs in sawflies to just a dozen in nest-provisioning wasps. Reduction in reproductive potential in evolutionary derived Hymenoptera is often facilitated by advanced behavioral mechanisms and nesting strategies. Here we describe a surprising nesting behavior that was previously unknown in the entire animal kingdom: the use of a vestibular cell filled with dead ants in a new spider wasp (Hymenoptera: Pompilidae species collected with trap nests in South-East China. We scientifically describe the 'Bone-house Wasp' as Deuteragenia ossarium sp. nov., named after graveyard bone-houses or ossuaries. We show that D. ossarium nests are less vulnerable to natural enemies than nests of other sympatric trap-nesting wasps, suggesting an effective nest protection strategy, most likely by utilizing chemical cues emanating from the dead ants.

The nest predator assemblage for songbirds in Mono Lake basin riparian habitats

Science.gov (United States)

Quresh S. Latif; Sacha K. Heath; Grant Ballard

2012-01-01

Because nest predation strongly limits avian fitness, ornithologists identify nest predators to inform ecological research and conservation. During 2002–2008, we used both video-monitoring of natural nests and direct observations of predation to identify nest predators of open-cup nesting riparian songbirds along tributaries of Mono Lake, California. Video cameras at...

Time-lapse video sysem used to study nesting gyrfalcons

Science.gov (United States)

Booms, Travis; Fuller, Mark R.

2003-01-01

We used solar-powered time-lapse video photography to document nesting Gyrfalcon (Falco rusticolus) food habits in central West Greenland from May to July in 2000 and 2001. We collected 2677.25 h of videotape from three nests, representing 94, 87, and 49% of the nestling period at each nest. The video recorded 921 deliveries of 832 prey items. We placed 95% of the items into prey categories. The image quality was good but did not reveal enough detail to identify most passerines to species. We found no evidence that Gyrfalcons were negatively affected by the video system after the initial camera set-up. The video system experienced some mechanical problems but proved reliable. The system likely can be used to effectively document the food habits and nesting behavior of other birds, especially those delivering large prey to a nest or other frequently used site.

Evaluación de la prueba ICT Malaria P. f/P.v ( AMRAD ® para la detección de P. falciparum y P. vivax en una zona endémica de la Amazonía peruana

Directory of Open Access Journals (Sweden)

Fernando Llanos-Zavalaga

2002-01-01

Full Text Available Objetivo: Evaluar el rendimiento del ICT MALARIA P.f/P.v (AMRAD® en pacientes febriles del departamento de Loreto, Perú. Materiales y métodos: estudio transversal realizado de agosto a setiembre del 2000, en pacientes con historia de fiebre (temperatura axilar 37,5°C en los últimos 3 días, sin un foco aparente. Se obtuvo una muestra de sangre para gota gruesa cuya lectura se realizó por un microscopista experto. Simultáneamente, se realizó la prueba rápida por un asistente de campo. Se calculó la sensibilidad, especificidad, valores predictivos, exactitud e índice de concordancia utilizando la gota gruesa como prueba de oro. Resultados: se incluyeron 79 pacientes de 5 meses - 70 años de edad. La sensibilidad y especificidad del AMRAD ® fueron 60,0% y 70,0%, respectivamente. El valor predictivo positivo (VPP, valor predictivo negativo (VPN y exactitud de la prueba fueron 36,0%, 88,8% y 70,9%, respectivamente. Se encontró pobre concordancia de la prueba con la gota gruesa (kappa=0,279. Conclusión: es necesario continuar con la evaluación de las pruebas rápidas para un diagnóstico oportuno y un tratamiento efectivo de la malaria.

Valoración de la prueba pericial para determinar la culpabilidad en casos de reincidencia en falsedad documental. Barranquilla 2008-2011

OpenAIRE

Manotas, José David; Guzmán González, Patricia; Barrios Lozano, Alberto

2015-01-01

El objetivo de esta tesis es analizar los criterios empleados por el juez en la valoración de la prueba pericial (caligráfica) en la determinación de la culpabilidad en los casos donde se presenta reincidencia en el delito de falsedad documental.

Concentrated nesting of mallards and gadwalls on Miller Lake Island, North Dakota

Science.gov (United States)

Duebbert, H.F.; Lokemoen, J.T.; Sharp, D.E.

1983-01-01

Island-nesting mallards (Anas platyrhynchos) and gadwalls (A. strepera) were studied on a 4.5-ha island in 385-ha Miller Lake in northwestern North Dakota during 1976-80. During the 5-year study, 2,561 duck nests of 9 species were found on Island A located 180 m offshore; 59% were mallard and 34% were gadwall. In patches of shrub cover, which contained the greatest concentrations of nests, densities ranged from 241 to 389 mallard nests/ha and from 139 to 237 gadwall nests/ha. Over 97% of the nests were placed in 4 patches of shrubs totaling about 1 ha of western snowberry (Symphoricarpos occidentalis)--Woods rose (Rosa woodsii) cover, which composed about 30% of the island's vegetation. Average hatching success was 85% for clutches of all species. Abandonment averaged 14% (348 of 2,426 nests) and was the major cause of egg failure. Only 15 nests (eggs in successful nests averaged 83% for mallards and 87% for gadwalls. Despite the close spacing of nests, most individual hens maintained normal nesting regimes. Eighty-one percent of the mallard clutches contained 7-13 eggs and 81% of the gadwall clutches contained 8-14 eggs. Island A in Miller Lake provides an outstanding example of the potential for high reproduction levels of mallards and gadwalls nesting in small areas of predator-free habitats.

Human papillomavirus detection and typing using a nested-PCR-RFLP assay.

Science.gov (United States)

Coser, Janaina; Boeira, Thaís da Rocha; Fonseca, André Salvador Kazantzi; Ikuta, Nilo; Lunge, Vagner Ricardo

2011-01-01

It is clinically important to detect and type human papillomavirus (HPV) in a sensitive and specific manner. Development of a nested-polymerase chain reaction-restriction fragment length polymorphism (nested-PCR-RFLP) assay to detect and type HPV based on the analysis of L1 gene. Analysis of published DNA sequence of mucosal HPV types to select sequences of new primers. Design of an original nested-PCR assay using the new primers pair selected and classical MY09/11 primers. HPV detection and typing in cervical samples using the nested-PCR-RFLP assay. The nested-PCR-RFLP assay detected and typed HPV in cervical samples. Of the total of 128 clinical samples submitted to simple PCR and nested-PCR for detection of HPV, 37 (28.9%) were positive for the virus by both methods and 25 samples were positive only by nested-PCR (67.5% increase in detection rate compared with single PCR). All HPV positive samples were effectively typed by RFLP assay. The method of nested-PCR proved to be an effective diagnostic tool for HPV detection and typing.

Do ducks and songbirds initiate more nests when the probability of survival is greater?

Science.gov (United States)

Grant, Todd A.; Shaffer, Terry L.

2015-01-01

Nesting chronology in grassland birds can vary by species, locality, and year. The date a nest is initiated can influence the subsequent probability of its survival in some grassland bird species. Because predation is the most significant cause of nest loss in grassland birds, we examined the relation between timing of nesting and nest survival. Periods of high nest survival that correspond with the peak of nesting activity might reflect long-term adaptations to specific predation pressures commonly recurring during certain periods of the nesting cycle. We evaluated this theory by comparing timing of nesting with date-specific nest survival rates for several duck and passerine species breeding in north-central North Dakota during 1998–2003. Nest survival decreased seasonally with date for five of the seven species we studied. We found little evidence to support consistent relations between timing of nesting, the number of nest initiations, and nest survival for any species we studied, suggesting that factors other than nest predation may better explain nesting chronology for these species. The apparent mismatch between date-specific patterns of nest survival and nest initiation underscores uncertainty about the process of avian nest site selection driven mainly by predation. Although timing of nesting differed among species, the general nesting period was fairly predictable across all years of study, suggesting the potential for research activities or management actions to be timed to take advantage of known periods when nests are active (or inactive). However, our results do not support the notion that biologists can take advantage of periods when many nests are active and survival is also high.

The nest architecture of the Florida harvester ant, Pogonomyrmex badius

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Walter R. Tschinkel

2004-07-01

Full Text Available The architecture of the subterranean nests of the Florida harvester ant, Pogonomyrmex badius, was studied through excavation and casting. Nests are composed of two basic units: descending shafts and horizontal chambers. Shafts form helices with diameters of 4 to 6 cm, and descend at an angle of about 15-20° near the surface, increasing to about 70° below about 50 cm in depth. Superficial chambers (< 15 cm deep appear to be modified shafts with low angles of descent, and are distinct from deeper chambers. In larger nests, they have a looping, connected morphology. Chambers begin on the outside of the helix as horizontal-floored, circular indentations, becoming multi-lobed as they are enlarged. Chamber height is about 1 cm, and does not change with area. Chamber area is greatest in the upper reaches of the nest, and decreases with depth. Vertical spacing between chambers is least in the upper reaches and increases to a maximum at about 70 to 80% of the maximum depth of the nest. The distribution of chamber area is top-heavy, with about half the total area occurring in the top quarter of the nest. Each 10% depth increment of the nest contains 25 to 40% less area than the decile above it, no matter what the size of the nest.

Greater sage-grouse nest predators in the Virginia Mountains of northwestern Nevada

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Lockyer, Zachary B.; Coates, Peter S.; Casazza, Michael L.; Espinosa, Shawn; Delehanty, David J.

2013-01-01

Greater sage-grouse Centrocercus urophasianus, hereafter sage-grouse, populations have declined across their range due to the loss, degradation, and fragmentation of habitat. Habitat alterations can lead not only to vegetative changes but also to shifts in animal behavior and predator composition that may influence population vital rates, such as nest success. For example, common ravens Corvus corax are sage-grouse nest predators, and common raven abundance is positively associated with human-caused habitat alterations. Because nest success is a central component to sage-grouse population persistence, research that identifies factors influencing nest success will better inform conservation efforts. We used videography to unequivocally identify sage-grouse nest predators within the Virginia Mountains of northwestern Nevada, USA, from 2009 to 2011 and used maximum likelihood to calculate daily probability of nest survival. In the Virginia Mountains, fires, energy exploration, and other anthropogenic activities have altered historic sage-grouse habitat. We monitored 71 sage-grouse nests during the study, placing video cameras at 39 nests. Cumulative nest survival for all nests was 22.4% (95% CI, 13.0–33.4%), a survival rate that was significantly lower than other published results for sage-grouse in the Great Basin. Depredation was the primary cause for nest failure in our study (82.5%), and common ravens were the most frequent sage-grouse nest predator, accounting for 46.7% of nest depredations. We also successfully documented a suite of mammalian and reptilian species depredating sage-grouse nests, including some predators never previously confirmed in the literature to be sage-grouse nest predators (i.e., bobcats Lynx rufus and long-tailed weasels Mephitis frenata). Within the high elevation, disturbed habitat of the Virginia Mountains, low sage-grouse nest success may be limiting sage-grouse population growth. These results suggest that management actions that

Nested high voltage generator/particle accelerator

International Nuclear Information System (INIS)

Adler, R.J.

1992-01-01

This patent describes a modular high voltage particle accelerator having an emission axis and an emission end, the accelerator. It comprises: a plurality of high voltage generators in nested adjacency to form a nested stack, each the generator comprising a cup-like housing having a base and a tubular sleeve extending from the base, a primary transformer winding encircling the nested stack; a secondary transformer winding between each adjacent pair of housings, magnetically linked to the primary transformer winding through the gaps; a power supply respective to each of the secondary windings converting alternating voltage from its respective secondary winding to d.c. voltage, the housings at the emission end forming a hollow throat for particle acceleration, a vacuum seal at the emission end of the throat which enables the throat to be evacuated; a particle source in the thrond power means to energize the primary transformer winding

Larvae and Nests of Aculeate Hymenoptera (Hymenoptera: Aculeata) Nesting in Reed Galls Induced by Lipara spp. (Diptera: Chloropidae) with a Review of Species Recorded. Part II.

Science.gov (United States)

Astapenková, Alena; Heneberg, Petr; Bogusch, Petr

2017-01-01

The ability of aculeate Hymenoptera to utilize wetlands is poorly understood, and descriptions of their nests and developmental stages are largely absent. Here we present results based on our survey of hymenopterans using galls induced by Lipara spp. flies on common reed Phragmites australis in the years 2015-2016. We studied 20,704 galls, of which 9,446 were longitudinally cut and the brood from them reared in the laboratory, while the remaining 11,258 galls reared in rearing bags also in laboratory conditions. We recorded eight species that were previously not known to nest in reed galls: cuckoo wasps Chrysis rutilans and Trichrysis pumilionis, solitary wasps Stenodynerus chevrieranus and Stenodynerus clypeopictus, and bees Pseudoanthidium tenellum, Stelis punctulatissima, Hylaeus communis and Hylaeus confusus. Forty five species of Hymenoptera: Aculeata are known to be associated with reed galls, of which 36 make their nests there, and the other are six parasitoids of the family Chrysididae and three cuckoo bees of the genus Stelis. Of these species, Pemphredon fabricii and in southern Europe also Heriades rubicola are very common in reed galls, followed by Hylaeus pectoralis and two species of the genus Trypoxylon. We also found new host-parasite associations: Chrysis angustula in nests of Pemphredon fabricii, Chrysis rutilans in nests of Stenodynerus clypeopictus, Trichrysis pumilionis in nests of Trypoxylon deceptorium, and Stelis breviuscula in nests of Heriades rubicola. We provide new descriptions of the nests of seven species nesting in reed galls and morphology of mature larvae of eight species nesting in reed galls and two parasitoids and one nest cleptoparasite. The larvae are usually very similar to those of related species but possess characteristics that make them easy to distinguish from related species. Our results show that common reeds are not only expansive and harmful, but very important for many insect species associated with habitats

Black-chinned hummingbird nest-site selection and nest survival in response to fuel reduction in a southwestern riparian forest

Science.gov (United States)

D. Max Smith; Deborah M. Finch; David L. Hawksworth

2009-01-01

Despite widespread efforts to avert wildfire by reducing the density of flammable vegetation, little is known about the effects of this practice on the reproductive biology of forest birds. We examined nest-site selection and nest survival of the Black-chinned Hummingbird (Archilochus alexandri) in New Mexico riparian forests treated or not for fuel...

Microhabitat characteristics of Lapland Longspur, Calcarius lapponicus, nests at Cape Churchill, Manitoba

Science.gov (United States)

Boal, C.W.; Andersen, D.E.

2005-01-01

We examined microsite characteristics at 21 Lapland Longspur (Calcarius lapponicus) nests and land cover types in which they occurred in Wapusk National Park, Cape Churchill, Manitoba. Nests were located in four of six physiographic-vegetation land-cover types. Regardless of land-cover type, all but one nest was built on a pressure ridge or mound. Nests were built midway between the bottom and top of ridges or mounds with steeper slopes than was randomly available. Longspur nests had a distinctive southwest orientation (P < 0.001). Longspurs selected nest sites that consisted of comparatively greater amounts of shrub species and lesser amounts of moss than were randomly available. Nests were generally well concealed by vegetation (mean = 67.0%) and concealment was negatively associated with amount of graminoid species at the nest (P = 0.0005). Our nesting habitat data may facilitate a better understanding of breeding Lapland Longspur habitat requirements, and potential impacts of habitat degradation by increasing Snow Goose (Chen caerulescens) populations in the study area.

Interspecific and intraspecific spatial separation by birds breeding in nest boxes

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Denis C. Deeming

2017-12-01

Full Text Available Nest boxes can be seen as a conservation tool for improving low-grade nesting habitat but it is unclear how sympatric species using boxes establish a spatial distribution relative to conspecifics and heterospecifics. This study determined the distances between nest boxes occupied by Blue Tits (Cyanistes caeruleus and Great Tits (Parus major in two British woodlands to ascertain whether spatial distribution was affected by species and, if it was, whether there were reproductive consequences of this breeding distribution. Occupancy of nest boxes at two woodland sites were recorded on an annual basis between 2010 and 2014, inclusive. Distances between nest boxes, and reproductive activity, were recorded. Even if nest boxes showed a clumped distribution in the woodlands, the occupancy of the boxes was random. Not all boxes were used and the minimum distance between occupied boxes was at least twice the distance between boxes in general. Blue Tits tended to have greater distances between boxes containing conspecifics but distances between boxes containing heterospecifics were generally of comparable lengths. Reproductive output was only affected in relation to clutch size for Blue Tits nesting at one site. Nest boxes that aim to improve habitats that lack suitable nesting sites should be placed to reflect actual dispersal distances of the focal bird species.

Does nest luminosity play a role in recognition of parasitic eggs in domed nests? A case study of the red bishop

Czech Academy of Sciences Publication Activity Database

Honza, Marcel; Šulc, Michal; Cherry, M. I.

2014-01-01

Roč. 101, č. 12 (2014), s. 1009-1015 ISSN 0028-1042 Institutional support: RVO:68081766 Keywords : Brood parasitism * Domed nest * Egg discrimination * Light conditions * Nest luminosity Subject RIV: EG - Zoology Impact factor: 2.098, year: 2014

Nesting Bird “Host Funnel” Increases Mosquito-Bird Contact Rate

OpenAIRE

CAILLOUËT, KEVIN A.; RIGGAN, ANNA E.; BULLUCK, LESLEY P.; CARLSON, JOHN C.; SABO, ROY T.

2013-01-01