Mostrando recursos 81 - 100 de 1,560

  1. Potencial de aislamientos fúngicos nativos para el manejo de Diaphorina citri (Hemiptera: Liviidae)

    Jaramillo Mazo, Claudia Yuliet
    Resumen: El cultivo de cítricos, representado principalmente por la naranja, la lima ácida y la mandarina, es considerado uno de los frutales más importantes a nivel mundial. La enfermedad causada por la bacteria Candidatus Liberibacter sp. y transmitida por el vector Diaphorina citri en América, es calificada como uno de los problemas fitosanitarios más devastadores en el cultivo. Una de las estrategias utilizadas para el control de la enfermedad hasta el momento, es el manejo del psílido asiático de los cítricos. Sin embargo, el principal método de control utilizado está relacionado con el uso de agroquímicos lo cual podría ocasionar...

  2. Producciónn xeno-free de Células Madre Mesenquimales derivadas de tejido adiposo, y evaluación de su secretoma neovasculairzante

    Escobar Soto, Carlos Hugo
    Introducción. Las moléculas de origen animal o bacteriano que habitualmente son usadas en los protocolos de extracción, cultivo y criopreservación de Células Madre derivadas de Tejido Adiposo humano (human Adipose derived Stem Cells, hASC) significan un riesgo de rechazo inmunológico contra las células trasplantadas y/o desarrollo de zoonosis. La capacidad de inducir la regeneración tisular de las ASC, depende al menos en parte, de factores de efecto paracrino liberados por ellas. Pero también se ha demostrado que la capacidad de inducir regeneración tisular, tiene una relación inversa con el pase al que se encuentran las células. Caracterizar el secretoma neovascularizante...

  3. High plasticity of loggerhead nesting site fidelity: from using repeatedly the same small beach during different seasons to deposit consecutive nests in different islands distant more than 100 km

    Abella Pérez, Elena; Sanz, Paula; Loureiro, Nuno de Santos; Cozens, Jacquie; Oujo-Alamo, Carolina; Martins, Samir; Marco, Adolfo; Varo Cruz, Nuria; López-Jurado, Luis Felipe

    [EN] Sea turtles exhibit a strong natal homing associated with a high nesting site philopatry. Mark-recapture and genetic studies confirm these patterns suggesting differences among and within species. In the present study, we have analysed the degree of nest site fidelity of a loggerhead population nesting on the islands of Cape Verde and have evaluated the existence of intrapopulational variability in this trait. The loggerhead is the only sea turtle species that nests in Cape Verde, and 15,000–25,000 nests per season have been estimated for the whole archipelago.

  4. Causes of extreme variability of nest density among close and similar beaches of Boavista island (Cape Verde): From 1 to 2000 annual nests per km.

    Marco, Adolfo; Liria-Loza, Ana; Martins, Samir; Abella Pérez, Elena; López-Jurado, Luis Felipe

    [EN] The 70 km of white sandy beaches of Boa Vista island in Cape Verde harbours one of the largest rookeries of the endangered loggerhead sea turtle, Caretta caretta. From middle June to early October, approximately 2000 to 4000 females lay up to 20000 nests annually. However, female beach selection, nesting success and nest density strongly varies among beaches and spatial patterns of nest abundance and distribution are relatively constant among seasons. The numbers of nesting activities and nests have been recorded along all beaches of the island during four nesting seasons (2007-2010)

  5. Climate change and the evolution of loggerhead sex-ratio in Cabo Verde

    Abella Pérez, Elena; Marco, Adolfo; López-Jurado, Luis Felipe

    [EN] Global warming can affect nesting success of sea turtles due to the rise of the sea level and the subsequent increased inundation or erosion of nesting beaches. Moreover, it can reduce male production to levels that can alter reproduction due to their temperature dependant sex determination (TSD). Now, mean nest temperatures all around the world predict a predominance of female hatchlings, and this trend may increase with global warming in the next decades.

  6. Why are egg fertilization rates not correlated with hatching success in sea turtles?

    Abella Pérez, Elena; Marco, Adolfo; López-Jurado, Luis Felipe

    [EN] The relative number of developing eggs is directly affected by fertilization rate, and unfertile eggs may indirectly negatively affect development of viable eggs within the nest. Thus, the number of viable eggs at laying should influence hatching success. We have studied both parameters in a nesting population of loggerhead turtles from Boavista Island (Republic of Cabo Verde). Fertility was estimated based on eggs excavated from nests within the first 96 hours after deposition. Our results confirm a high egg fertilization rate for the species, which exceeded an average of 94% fertility (95% confidence limits: 91.9 and 96.2%, N=43 nests).

  7. Sea turtles recovered at the Wild Fauna Recovery Center in Gran Canaria (Canary Islands, Spain)

    Calabuig, P.; Liria-Loza, Ana; López-Jurado, Luis Felipe

    [EN] Since the beginning of the 1990's, the Wild Fauna Recovery Center in Gran Canaria Canary Islands, Spain) has received a large number of injured animals for recovery. Apart from birds and mammals, a considerable number of sea turtles representing different species are gathered each year. During the last five years (1999-2003), more than 100 turtles were sheltered annually; more than 80% successfully recovered and were released.

  8. Satellite tracking of adult loggerheads (Caretta caretta L.) around waters of Cape Verde Archipielago (Western Africa)

    Cejudo, Daniel; Varo Cruz, Nuria; López, Óscar; López-Jurado, Luis Felipe

    [EN] During the 1999 nesting season (from June to October), four satellite transmitters were attached to two males and two females of Caretta caretta from Boavista Island (Cape Verde Archipelago, western Africa), where density of nesting females is the highest in the whole archipelago. Transmitters did not work as well as expected, resulting in a low number of locations, possibly due to the neritic behavior of adult loggerheads at reproductive habitat, with the antennae exposed to continuous rubbing. Therefore, we establish a conservative hypothesis about movements of C.caretta in Cape Verde.

  9. Preliminary approach to the hatchlings sex-ratio of a population of Caretta caretta of Boavista island, Cape Verde Archipielago (Western Africa).

    Delgado, Cláudia; Dellinger, Thomas; Varo Cruz, Nuria; Cejudo, Daniel; López-Jurado, Luis Felipe

    [EN] A nesting population of loggerhead sea turtles Caretta caretta has recently been described for Boa Vista Island, Cape Verde Archipelago (Western Africa). Since 1998, “Projecto Cabo Verde Natura 2000” has monitored three beaches during the turtle breeding season. The beaches being monitored - Calheta, Errata and Ponta Cosme - are located in the southeast part of Boa Vista Island. This work intends to give a first insight into the Boa Vista Island sea turtle population’s sex ratio using a histological approach, as sexual determination in sea turtles is known to be temperature-dependent (TSD or temperature-dependent sex determination).

  10. Comparative study of the epibionts on the pelagic and mature female loggerhead turtles on the Canary and Cape Verde islands

    Liria-Loza, Ana; López-Jurado, Luis Felipe

    [EN] Marine turtles commonly carry diverse forms of epizoa on their shells. The occurrence of a particular species may ultimately help to clarify certain questions about sea turtle natural life history. This paper gives a detailed and comparative list of epizoic species found on two populations of macaronesian loggerheads: pelagic and juveniles living around the Canary Islands and mature females nesting in Boavista Island, Cabo Verde. For the epizoic flora, the most important genera founded is Polysiphonia (Rhodophiceae); P. carettia for the pelagics and Polysiphonia sp. for the nesting animals.

  11. Temporary sequences and description of the emergency of newborns loggerhead in the Cape Verde archipelago

    Abella Pérez, Elena; López-Jurado, Luis Felipe

    [EN] Sea turtles bury their eggs in the sand of the beach, where they incuba te. After a period of approximately two months, hatchlings break the eggshell and remain inside the chamber for three to seven days (Hays & Speakman, 1993). Then they leave the nest and emerge to the surface of the beach, going quickly towards the surf, to begin their pelagic and developmental stage (e.g., López-Jurado & Andreu, 1998). Hatchlings usually do not emerge from the nest as a single group. They emerge in groups at different moments, resulting in more than one emergence per nest during sorne...

  12. Lost at sea: Genetic, oceanographic and meteorological evidence for storm-forced dispersal

    Monzón Argüello, Catalina; Dell’ Amico, F.; Morinière, P.; Marco, Adolfo; López-Jurado, Luis Felipe; Hays, Graeme; Scott, Rebecca; Marsh, Robert; Lee, Patricia

    [EN] For many species, there is broad-scale dispersal of juvenile stages and/or long-distance migration of individuals and hence the processes that drive these various wide-ranging move- ments have important life-history consequences. Sea turtles are one of these paradigmatic long-distance travellers, with hatchlings thought to be dispersed by ocean currents and adults often shuttling between distant breeding and foraging grounds. Here, we use multi- disciplinary oceanographic, atmospheric and genetic mixed stock analyses to show that juvenile turtles are encountered ‘downstream’ at sites predicted by currents. However, in some cases, unusual occurrences of juveniles are more readily explained by storm events and...

  13. Injuries observed in nesting females of loggerhead turtles on Boavista island (Cabo Verde Archipelago)

    Vázquez, Cristina; Varo Cruz, Nuria; López, Óscar; Liria-Loza, Ana; López-Jurado, Luis Felipe

    [EN] Different kinds of physical anomalies are frequently observed in any sea turtle breeding population. Nesting beaches are an excellent place to study the injuries and defects that occur in adult females. The archipelago of Cape Verde is situated about 500 km of Senegal, West Africa. Boavista is the eastern most island and may constitute the most important nesting area for the loggerhead turtle in the archipelago. The studies conducted from 1998 to 2004 indicate that Cape Verde might account for one of the most important loggerheads populations in the eastern Atlantic. The nesting females in Boavista were surveyed during...

  14. Loggerhead nesting trend in three beaches of Boavista, Cape Verde archipelago

    Liria-Loza, Ana; Varo Cruz, Nuria; Medina Suárez, María E.; Jiménez Bordón, Saray; López-Jurado, Luis Felipe

    [EN] Nesting beach surveys are the most widely implemented monitoring tool in use by the global sea turtle community and are an important component of a comprehensive program to assess and monitor the status of sea turtle populations. These assessments are necessary to evaluate the effects of recovery and conservation activities that are being implemented at all life history stages. Monitoring techniques employed on nesting beaches range from highly structured standardized sampling to “snapshots” of nesting activity within a nesting season. Very long-term nest counts data (more than twenty years) were analyzed for some turtle populations.

  15. Synchrony on embryonic development of marine turtles: individual variability and environmental effects

    Pérez García, Héctor; García Cerdá, Rosa María; Fernández Gil, Belén; Marco, Adolfo; Abu Raya, Mara; López-Jurado, Luis Felipe

    [EN] For sea turtles, to hatch and emerge from the nest communally is essential to decrease hatchling mortality. Thus, it is very important within a nest the simultaneous fertilization and the synchronized embryonic development of all eggs. On loggerhead nesting beaches of Cape Verde we have studied the individual variability on developmental synchrony of embryos and the influence on this process of some biological, environmental and management factors. We have compared this trait within and between 34 nests naturally incubated on the beach and 34 nests relocated to a beach hatchery during the 2009 and 2010 nesting seasons.

  16. Caracterización de la arquitectura del sueño en el modelo murino de desmielinización por cuprizona

    Cárdenas Corredor, Diana Carolina
    La esclerosis múltiple es una enfermedad crónica, inflamatoria y desmielinizante, que afecta el sistema nervioso central. En humanos con esclerosis múltiple se han reportado alteraciones de sueño que tienen impacto negativo en la calidad de vida de los pacientes. Este estudio tiene como objetivo la caracterización de la arquitectura del sueño en el modelo murino de desmielinización por cuprizona. Para este propósito ocho animales derivados de ratas wistar del laboratorio Charles Rivers fueron utilizados. Los sujetos fueron divididos en dos grupos, experimental y control. Los animales experimentales fueron implantados con cinco electrodos craneales y uno cervical, para registrar electroencefalograma (EEG)...

  17. Determinación del estado de susceptibilidad a ddt y piretroides y los mecanismos de resistencia en poblaciones de Aedes aegypti (Díptera: Culicidae) de los municipios de la Mesa (Cundinamarca) y Bucaramanga (Santander)

    Murcia Ramírez, Carlos Humberto
    Las infecciones por virus dengue y chikungunya son enfermedades transmitidas principalmente por el mosquito Aedes aegypti en las Américas. En Colombia son un importante problema de salud pública y ante la ausencia de una vacuna efectiva, el control vectorial es el principal mecanismo de control. En el país se usó DDT desde 1959 hasta finales de los 60s durante la campaña de eliminación del Ae. aegypti. Ante la presión de selección ejercida con este insecticida sobre las poblaciones de Ae. aegypti, se generaron poblaciones resistentes, conllevando a la suspensión de esta molécula en la década de 1980 para el control...

  18. Mecanismo moleculares de desarrollo y desintegración del catílago de Meckel, revisión sistemática de literatura

    Urrea Franco, Mónica
    El cartílago de Meckel tiene su origen en células de cresta neural, que migran y originan el cartílago en el estadío 12.5 (E12.5) del desarrollo de ratas; es un cartílago hialino típico, con los condrocitos embebidos en una matriz rica en colágeno tipo II; corresponde a una estructura transitoria que inicia su degradación hacía E16; la porción proximal del cartílago da origen al yunque y martillo por osificación endocondral, la porción distal se incorpora a la sínfisis mandibular y en su porción media, se da origen al ligamento esfenomandibular por la parte más posterior, la anterior sufre un proceso de...

  19. Ambiente acústico de/en la vivienda: al encuentro de una visión holística

    Patricio, Jorge
    En la antigüedad clásica, la estructura del conocimiento se basaba en la filosofía introspectiva, en la medicina, en la matemática y en la astrología, definiendo así las ciencias de la vida y de la reflexión Humana. En el trascurso de los años, debido al desarrollo de las metodologías de aná- lisis y del propio pensamiento, el conocimiento científico ha empezado a dividirse en áreas cada vez más especializadas, originando ramas de conocimiento, las cuales, aun pareciendo diferentes, parten de una misma visión filosófica y científica. Y con la acústica no ha sido diferente! Derivada de la física e incorporada en soluciones tecnológicas aplicadas a la propagación, a la recepción y a...

  20. Caracterización funcional de un canal de cloruro CLC de Leishmania

    Garcia Otalora, Michel Andrés
    Leishmania spp., abarca organismos unicelulares eucariota con un ciclo de vida caracterizado por dos grandes estadíos (promastigote y amastigote) expuestos a diferencias de pH, osmolaridad y temperatura. Dados estos cambios, se espera que el parásito desarrolle mecanismos regulatorios para su supervivencia. Estudios previos en promastigotes han descrito bombas H+ ATPasas que generan un gradiente electroquímico útil para el transporte secundario de nutrientes (Zilberstein & Shapira, 1994), y que están acopladas a transportadores aniónicos (Vieira, Slotki, & Cabantchik, 1995; Vieira, Lavan, Dagger, & Cabantchik, 1994). Hasta el momento, se conoce poco respecto a la naturaleza molecular o al papel que desempeñan...

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