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Prevalence of blood parasites in Tyrannidae (flycatchers) in the Eastern plains of Colombia
Matta, Nubia E;Basto, Natalia;Gutierrez, Rafael;Rodríguez, Oscar A;Greiner, Ellis C;
Memórias do Instituto Oswaldo Cruz , 2004, DOI: 10.1590/S0074-02762004000300005
Abstract: blood samples from 159 birds of the new-world family tyrannidae (the flycatchers) from the eastern plains of colombia, were examined for haematozoa parasites, in 1999-2000. haematozoa were detected in six of 20 species. the overall prevalence was 10.1%. the most common parasites detected were microfilariae, followed by trypanosoma and plasmodium. the highest prevalence (9.6%) was found in the ochre-bellied flycatcher (mionectes oleaginea). mixed infections with more than one genus of blood parasite were rare and most infections encountered were of low intensity. the results of this study suggest an important role of ecologically diverse conditions determining composition, transmission, and prevalence of a blood parasite fauna, presumably through host interaction population density. some new host parasite relationship records are presented.
Problemas centrales del análisis de datos cualitativos
Julio Mejía Navarrete
Revista Latinoamericana de Metodologia de la Investigacion Social , 2011,
Abstract: El trabajo examina las operaciones prácticas y las decisiones concretas que enfrenta el trabajo de investigación cualitativa en la etapa del análisis de datos. Interesa subrayar los aspectos centrales del análisis de datos cualitativos que posibiliten abrir una discusión en la investigación metodológica de América Latina
Foraging behavior of tyrant flycatchers (Aves, Tyrannidae) in Brazil
Gabriel, Vagner de A.;Pizo, Marco A.;
Revista Brasileira de Zoologia , 2005, DOI: 10.1590/S0101-81752005000400036
Abstract: in this paper we present data on the foraging maneuvers and substrates used to capture preys by 28 species of tyrant flycatchers (tyrannidae) in brazil. for six species: arundinicola leucocephala linnaeus, 1764, fluvicola nengeta linnaeus, 1766, machetornis rixosa vieillot, 1819, myiozetetes similis spix, 1825, pitangus sulphuratus linnaeus, 1766, and tyrannus melancholicus vieillot, 1819 -, we go further to investigate perch height, search time, sally distance, and sally angle. with a few exceptions, sally strike was the most frequent foraging maneuver. living foliage and air were the most frequent substrates used to capture preys. among the six species studied in detail we found three distinct groups of perch heights: f. nengeta and m. rixosa foraged on the ground, a. leucocephala with p. sulphuratus were medium-height foragers, and t. melancholicus and m. similis form the third group for which prey attacks usually start from perches from the ground up to 3 m. with the exception of p. sulphuratus, which had the longest search time, the other five species did not differ in this aspect of the foraging behavior. three groups were also discernible in relation to sally distance: f. nengeta and m. rixosa usually attacked prey close (< 2 m) to them, a. leucocephala, p. sulphuratus and m. similis form a medium-distance (3-4 m) group, and t. melancholicus had the longest sally distances (up to 12 m). birds differ in details of the sally angle that, together with other subtle differences in the foraging behavior, may render important differences in prey selection.
Cloning and sequence analysis of Paralichthys olivaceus Follistatin cDNA
牙鲆Follistatin cDNA的克隆与序列分析

LIU Qing-hua,TAN Xun-gang,XU Yong-li,ZHANG Pei-jun,XU Peng,
刘庆华
,谭训刚,徐永立,张培军,徐破

浙江大学学报(农业与生命科学版) , 2007,
Abstract: To study the DNA sequence features of Follistatin gene in marine fish, Paralichthys olivaceus Follistatin cDNA was isolated and analyzed from Paralichthys olivaceus embryos 67 h after fertilization.The results indicated that there was no evidence for alternative splicing of Follistain in Paralichthys olivaceus.The length of Paralichthys olivaceus Follistatin cDNA was 963 bp.Sequence analysis revealed that Paralichthys olivaceus Follistatin was more closely related to Takifugu rubripes.The biological function of the highly conserved cysteine and glycin in Paralichthys olivaceus Follistatin protein might be maintaining the stabilization of protein structure.
Nest and nest-site reuse within and between breeding seasons by three neotropical flycatchers (Tyrannidae)
Aguilar, TM.;Marini, M?.;
Brazilian Journal of Biology , 2007, DOI: 10.1590/S1519-69842007000300020
Abstract: nest and or nest site reuse within and between breeding seasons was reported by the euler's flycatcher (lathrotriccus euleri), the sepia-capped flycatcher (leptopogon amaurocephalus) and the gray-hooded flycatcher (mionectes -rufiventris) in forest fragments from southeastern brazil. nest and or nest site reuse between some years was frequent within a single breeding season by the sepia-capped flycatcher. nest reuse, however, was not related to nesting success in the previous breeding attempt. nest turnover rates (movement to a new site between years) were low for l. amaurocephalus, intermediate for l. euleri and high for m. rufiventris.
Intraspecific differences in metabolic rate of Chroeomys olivaceus (Rodentia: Muridae): the effect of thermal acclimation in arid and mesic habitats
Novoa,F. Fernando; Rivera-hutinel,Antonio; rosenmann,Mario; Sabat,Pablo;
Revista chilena de historia natural , 2005, DOI: 10.4067/S0716-078X2005000200004
Abstract: studies of metabolic capacities in rodents have been largely studied at an inter-specific levels, but physiological capacities of populations belonging to the same species have received lesser attention. here we studied the maximum and basal metabolic rates of two populations of the rodent chroeomys olivaceus dwelling in habitats with contrasting temperature and rainfall regimes, and to test if differences in metabolic capacities are due to local adaptation or acclimatization effect. after four weeks of acclimation to 25 oc and 10 oc, the bmr and mmr were determined in individuals from the northern population of caleta loa, and the southern population of la picada. individuals from ?la picada? population were heavier than those from caleta loa. mmr and bmr exhibited higher values in cold acclimated animals compared with warm-acclimated animals. besides, bmr, but not mmr, was lower in caleta loa individuals, in spite of the acclimation treatment. hence, the differences in the metabolic capacities and the response to acclimation of c. olivaceus populations appear to be an evolutionary response to the environmental cues
Indicadores cualitativos de la sociedad de la información
Javier Echeverría
Nómadas , 2003,
Abstract: La sociedad de la información (SI) requiere un espacio para desarrollarse: el espacio electrónico, generado por las tecnologías de la información y de las comunicaciones (TIC). Si concebimos ese espacio sólo como un mercado informacional (acceso y contenidos), los indicadores que miden el desarrollo de la SI serán cuantitativos y tendrán un claro sesgo mercantilista. En cambio, si promovemos una sociedad civil de la información, tendremos que usar indicadores cualitativos que midan el desarrollo de la vida civil en el espacio electrónico y las capacidades de la ciudadanía por ser activa en él. Como ejemplo, se analiza críticamente el plan europeo e-Learning y los indicadores utilizados por la Unión Europea, centrados en la conexión a internet y el uso de las tecnologías multimedia. Partiendo de que la educación debe desarrollar ante todo las capacidades de acción en el espacio electrónico, se proponen indicadores cualitativos para la educación asistida por las TIC. Estos planteamientos pueden generalizarse a otras actividades sociales en el espacio electrónico.
Genetic Linkage Map of Olive Flounder, Paralichthys olivaceus
Jung-Ha Kang, Woo-Jin Kim, Woo-Jai Lee
International Journal of Biological Sciences , 2008,
Abstract: Olive flounder, Paralichthys olivaceus, is an important fish species in Asia, both for fisheries and aquaculture. As the first step for better understanding the genomic structure and functional analysis, we constructed a genetic linkage map for olive flounder based on 180 microsatellites and 31 expressed sequence tag (EST)-derived markers. Twenty-four linkage groups were identified, consistent with the 24 chromosomes of this species. The total map distance was 1,001.3 cM based on Kosambi sex-average mapping, and the average inter-locus distance was 4.7 cM. Linkage between the loci was identified by an LOD score of ≥3. This linkage map may be used to map quantitative trait loci associated with important traits of the species and may assist in breeding programs.
Helmintofauna del roedor Abrothrix olivaceus (Sigmodontinae) en áreas sub-urbanas de Santiago de Chile THE HELMINTHFAUNA OF THE RODENT Abrothrix olivaceus (SIGMODONTINAE) IN SUB-URBAN LOCALITIES OF SANTIAGO, CHILE  [cached]
CARLOS A LANDAETA-AQUEVEQUE,MARíA D. R ROBLES,PEDRO E CATTAN
Parasitología latinoamericana , 2007,
Abstract: El ratón oliváceo (Abrothrix olivaceus) se distribuye ampliamente a lo largo de Chile abarcando diversos ambientes. Su helmintofauna ha sido parcialmente estudiada en diversas áreas silvestres del país. En este trabajo se encontraron cinco especies de nemátodes y un cestode. Tres de estas especies parásitas se registran por primera vez en este hospedador: Syphacia obvelata, Physaloptera calnuensis y Heterakis spumosa, y esta última se registra por primera vez en Chile. Se sugiere que uno de los factores estructurantes es la localidad de muestreo: una de las tres localidades estudiadas presentó significativamente mayor abundancia media y prevalencia en dos especies de parásitos y como comunidad componente. Se sugiere que otro factor estructurante es la introducción de parásitos desde especies exóticas. éste es el primer estudio de la helmitofauna de este roedor en localidades suburbanas y en la Región Metropolitana. The wild rodent, Abrothrix olivaceus, is a widespread species in Chile using different habitats troughout the territory. Its helminthfauna has been partially studied in wild enviroments in Chile. In this work five nematodes and one species ofcestode were found. Three of them are first record in this host: Syphacia obvelata, Physaloptera calnuensis and Heterakis spumosa, and this last one, is first record in Chile. It is suggested that one structuring factor is the locality: one of the three localities studied had more mean abundance and prevalence in two parasites species and as a component community. It is also suggested that other structuring factor of this helminth community is the introduction of parasites from foreign species. This is the first study of its helminthes in sub-urban localities and in the Región Metropolitana.
Validación de inmunoensayos cualitativos usados para evaluar la inmunogenicidad de vacunas  [PDF]
Rolando Ochoa,Juan C. Martínez,Eric Estrada,Ana M. García
Vaccimonitor , 2000,
Abstract: Se realizó una revisión y actualización sobre la importancia de la validación de los inmunoensayos cualitativos usados para evaluar la inmunogenicidad de vacunas, sus principios y procedimientos. Se discutieron los principales parámetros empleados para evaluar estas técnicas. Se analizaron detalladamente los procedimientos para estudiar la sensibilidad, especificidad, valores predictivos positivos y negativos, valor de discriminación y zona gris. Se exponen nuestrasexperiencias.
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