827 resultados para virgins queens


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1956-1957 Miss Lincoln

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1941-1942 Miss Lincoln

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1940-1941 Miss Homecoming

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1939-1940 Miss Homecoming

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Funding This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme.

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A central issue in evolutionary biology is the extent to which complex social organization is under genetic control. We have found that a single genomic element marked by the protein-encoding gene Gp-9 is responsible for the existence of two distinct forms of social organization in the fire ant Solenopsis invicta. This genetic factor influences the reproductive phenotypes and behavioral strategies of queens and determines whether workers tolerate a single fertile queen or multiple queens per colony. Furthermore, this factor affects worker tolerance of queens with alternate genotypes, thus explaining the dramatic differences in Gp-9 allele frequencies observed between the two social forms in the wild. These findings reveal how a single genetic factor can have major effects on complex social behavior and influence the nature of social organization.

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The best mating strategy for males differs from that of females, because females gain from mating with several males (polyandry), but males gain from monopolizing the females. As a consequence, males have evolved a variety of methods, such as the transfer of inhibitory substances from their accessory glands, to ensure exclusive paternity of the female's offspring, generally with detrimental effects on female fitness. Inhibitory substances have been identified as peptides or other specific molecules. Unfortunately, in social insects male-mating traits are investigated only poorly, although male social insects might have the same fundamental influence on female-mating behavior as found in other species. A recently developed technique for the artificial insemination of bumblebee queens allowed us to investigate which chemical compound in the mating plug of male bumblebees, Bombus terrestris L., prevents females (queens) from further mating. Surprisingly, we found that the active substance is linoleic acid, a ubiquitous and rather unspecific fatty acid. Contrary to mating plugs in other insect species, the bumblebee mating plug is highly efficient and allows the males to determine queen-mating frequencies.

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The inadvertent introduction of the fire ant Solenopsis invicta to the United States from South America provides the opportunity to study recent social evolution by comparing social organization in native and introduced populations. We report that several important elements of social organization in multiple-queen nests differ consistently and dramatically between ants in Argentina and the United States. Colonies in Argentina contain relatively few queens and they are close relatives, whereas colonies in the United States contain high numbers of unrelated queens. A corollary of these differences is that workers in the native populations are significantly related to the new queens that they rear in contrast to the zero relatedness between workers and new queens in the introduced populations. The observed differences in queen number and relatedness signal a shift in the breeding biology of the introduced ants that is predicted on the basis of the high population densities in the new range. An additional difference in social organization that we observed, greater proportions of permanently unmated queens in introduced than in native populations, is predicted from the loss of alleles at the sex-determining locus and consequent skewing of operational sex ratios in the colonizing ants. Thus, significant recent social evolution in fire ants is consistent with theoretical expectations based on the altered ecology and population genetics of the introduced populations.

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The genetic relationships of colony members in the ant Myrmica tahoensis were determined on the basis of highly polymorphic microsatellite DNA loci. These analyses show that colonies fall into one of two classes. In roughly half of the sampled colonies, workers and female offspring appear to be full sisters. The remaining colonies contain offspring produced by two or more queens. Colonies that produce female sexuals are always composed of highly related females, while colonies that produce males often show low levels of nestmate relatedness. These results support theoretical predictions that workers should skew sex allocation in response to relatedness asymmetries found within colonies. The existence of a relatedness threshold below which female sexuals are not produced suggests a possible mechanism for worker perception of relatedness. Two results indicate that workers use genetic cues, not queen number, in making sex-allocation decisions. (i) The number of queens in a colony was not significantly correlated with either the level of relatedness asymmetry or the sex ratio. (ii) Sex-ratio shifts consistent with a genetically based mechanism of relatedness assessment were seen in an experiment involving transfers of larvae among unrelated nests. Thus workers appear to make sex-allocation decisions on the basis of larval cues and appear to be able to adjust sex ratios long after egg laying.

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Female moths often become depleted of sex pheromone after mating as the various components of virgin behavior are switched off. In examining a potential male contribution to these events in the corn earworm moth Helicoverpa zea, we have characterized a basic polypeptide from the tissues producing (accessory glands) and storing (duplex) the seminal fluids. The peptide evokes the depletion of sex pheromone when injected into virgin females. This pheromonostatic peptide (PSP) is 57 amino acids long and contains a single disulfide bridge. It is blocked at the N terminus with pyroglutamate and at the C terminus by amidation. As little as 23 ng of peptide evokes the near-complete depletion of pheromone in decapitated (neck-ligated) females that had been injected with pheromone biosynthesis-activating neuropeptide. Activity is approximately 15-fold less in intact virgins, showing that the head limits the expression of activity in these injected females. Females mated to surgically impaired males, capable of producing a spermatophore but not transferring spermatozoa or seminal fluids, are depleted of pheromone by injected peptide. Females whose abdominal nerve cords have been severed are not depleted of pheromone after mating. Thus, neural signals either descending or ascending via the nerve cord are required for the depletion of pheromone after mating. PSP, from the seminal fluids, may participate in this process by direct or indirect action on the glandular tissue; if so, it represents an unusual mechanism in insects for the regulation by seminal fluids of postmating reproductive behavior.

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Se presentan tres experiencias de innovación docente realizadas en la asignatura de Iniciación a las Habilidades Profesionales, primer curso del Grado en Trabajo Social, Universidad de Alicante. Objetivos: 1) Implicar en la docencia a las personas usuarias de los servicios, considerándolos expertos por su experiencia personal con Trabajadores Sociales y con la sociedad en general. 2) Proporcionar un contexto de aprendizaje que permita conocer, comprender y aprender a comunicarse profesionalmente con personas usuarias de servicios. Metodología: Aprendizaje significativo basado en la interacción con personas usuarias de los servicios con tres modalidades: a) Diseño conjunto de actividades de enseñanza-aprendizaje entre una entidad social y el profesorado de la asignatura Iniciación a las Habilidades Profesionales del Grado en Trabajo Social de la Universidad de Alicante; b) Diseño con enfoque multidisciplinar (profesorado de Trabajo Social con el profesorado de Ciencias de la Actividad Física y Deporte) y la entidad social; c) Diseño internacional con participación de las universidades Queen’s University, Belfast (Northern Ireland) (coordinadora del proyecto) junto con las universidades de Ljubljana (Slovenia) y Alicante. Los resultados proporcionan evidencias sobre la pertinencia de la colaboración docente de personas expertas por su experiencia y de la utilización de una metodología docente basada en el aprendizaje significativo para la adquisición de competencias.

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En el siglo XIX, la función política primordial de las reinas era contribuir a la estabilidad y perpetuación de la dinastía y de la corona, como esposas de reyes y madres de futuros reyes; mantener el buen funcionamiento del sistema político como regentes y, como reinas madre, dar de nuevo credibilidad a la monarquía dejando paso a los nuevos reyes. María Cristina de Borbón y María Cristina de Habsburgo fueron dos mujeres, dos reinas, que vieron condicionada su trayectoria personal por el hecho de ser regentes y su labor política por el hecho de ser mujeres. A medida que avanzaba el siglo XIX, las familias reales se mostraron de forma creciente como familias burguesas, para contribuir a ofrecer una imagen próxima y moderna de la corona. Sin embargo, las diferencias en este sentido entre las dos reinas son destacables, pues los modelos de género evolucionaron a lo largo de la centuria. Por otra parte, encarnaron dos momentos muy diferentes de la monarquía decimonónica: el punto de partida –una monarquía absoluta– y el de llegada –una monarquía constitucional–. María Cristina de Borbón, con mucha angustia personal y pánico a la revolución, vivió, muy a su pesar, el tránsito definitivo entre el Antiguo Régimen y el régimen liberal, mientras que María Cristina de Habsburgo ocupó el trono en la época dorada de la Restauración liberal, aunque su regencia tuvo que afrontar la crisis de finales de siglo.

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Contains the Inferior Court's register of debtor's cases heard for the Mayor's Court for the following counties: Orange County, Suffolk County, Westchester County, Ulster County, Duchess County, and Queens County, in New York state. The register, kept by William Wickham, cites parties to the action, sentencing, court costs, and has a name index at the end.

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This layer is a georeferenced raster image of the historic paper map entitled: Map of New-York Bay and Harbor and the environs : sheet no. 4, founded upon a trigonometrical survey under the direction of F.R. Hassler, superintendent of the Survey of the Coast of the United States ; triangulation by James Ferguson and Edmund Blunt, assistants ; the hydrography under the direction of Thomas R. Gedney, lieutenant U.S. Navy ; the topography by C. Renard and T.A. Jenkins assists. It was published by Survey of the Coast of the United States in 1844-1845. Scale 1:30,000. This layer is image 4 of 6 total images of the six sheet source map, representing the southwest portion of the map. The image inside the map neatline is georeferenced to the surface of the earth and fit to the Universal Transverse Mercator (UTM) Zone 18N NAD83 projection. All map collar and inset information is also available as part of the raster image, including any inset maps, profiles, statistical tables, directories, text, illustrations, or other information associated with the principal map. This map shows coastal features such as lighthouses, buoys, beacons, rocks, channels, points, coves, islands, bottom soil types, wharves, and more. Includes also selected land features such as roads, drainage, land cover, forts, selected buildings, towns, and more. Relief shown by hachures. Depths are shown by soundings and shading. Includes text, table of currents and stations, notes, sailing directions, 4 coastal panoramas and 2 views of Sandy Hook Light. This layer is part of a selection of digitally scanned and georeferenced historic maps from The Harvard Map Collection as part of the Imaging the Urban Environment project. Maps selected for this project represent major urban areas and cities of the world, at various time periods. These maps typically portray both natural and manmade features at a large scale. The selection represents a range of regions, originators, ground condition dates, scales, and purposes.