966 resultados para Nesting and reproduction
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The genus Mesophyllum Me. Lemoine includes around 147 species, of which only three have been referred to the Brazilian coast. Mesophyllum erubescens was originally described from Fernando de Noronha Archipelago, Brazil (type locality). Here we present the first detailed description of M. erubescens based on Brazilian material. Samplings were made through scuba diving at the Biological Marine Reserve of Arvoredo Island, Santa Catarina. The relations of M. erubescens with other similar species, especially from the American Atlantic studied by W.R. Taylor are discussed.
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We intend to study the algebraic structure of the simple orthogonal models to use them, through binary operations as building blocks in the construction of more complex orthogonal models. We start by presenting some matrix results considering Commutative Jordan Algebras of symmetric matrices, CJAs. Next, we use these results to study the algebraic structure of orthogonal models, obtained by crossing and nesting simpler ones. Then, we study the normal models with OBS, which can also be orthogonal models. We intend to study normal models with OBS (Orthogonal Block Structure), NOBS (Normal Orthogonal Block Structure), obtaining condition for having complete and suffcient statistics, having UMVUE, is unbiased estimators with minimal covariance matrices whatever the variance components. Lastly, see ([Pereira et al. (2014)]), we study the algebraic structure of orthogonal models, mixed models whose variance covariance matrices are all positive semi definite, linear combinations of known orthogonal pairwise orthogonal projection matrices, OPOPM, and whose least square estimators, LSE, of estimable vectors are best linear unbiased estimator, BLUE, whatever the variance components, so they are uniformly BLUE, UBLUE. From the results of the algebraic structure we will get explicit expressions for the LSE of these models.
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Crocodylomorph eggs are relatively poorly known in the fossil record when compared with skeletal remains, which are found all over the world, or when compared with dinosaur eggs. Herein are described crocodiloid eggshells from the Upper Jurassic Lourinhã Formation of Portugal, recovered from five sites: Cambelas (clutch), Casal da Rola, Peralta (eggshell fragments), and Paimogo North and South (three partial crushed eggs and eggshell fragments). The clutch of Cambelas, composed of 13 eggs, is the only sample not found in association with dinosaur eggshells. Morphological characters of the eggshells described herein, such as shell units and microstructure, are consistent with the crocodiloid morphotype. As such, this material is assigned to the oofamily Krokolithidae, making them the oldest known crocodylomorph eggs so far and the best record for eggs of non-crocodylian crocodylomorphs. Two new ootaxa are erected, Suchoolithus portucalensis oogen. et oosp. nov, for the clutch of Cambelas, and Krokolithes dinophilus, oosp. nov., for the remaining eggshells. The basic structure of crocodilian eggshells has remained stable since at least the Late Jurassic. Additionally, the findings suggest previously unknown biological associations with contemporary archosaurs, shedding light on the poorly understood egg morphology, reproduction strategies and paleobiology of crocodylomorphs during the Late Jurassic.
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Predation and alteration of microhabitats may represent high risk for nesting of Amazonian turtles. This study aimed at investigating the nesting and body parameters of neonates of Podocnemis unifilis in the Araguari River basin, State of Amapá, Brazil. The spawning sites of this turtle were monitored along the Falsino River (a region with two reserves) and in the urban area of the Porto Grande city along the Araguari River, from August to December 2011. A total of 180 nests were found and the nesting occurred from September to November, with prevalence in October. Eggs hatching occurred in December. The mean incubation period was 63.5 ± 5.2 days and the eggs hatching success was 25%. However, approximately 80% of the nests had suffered predation mainly by humans, which occurred in both the protected areas of the reserves and the urban area. The pattern of nesting site choice was discussed. Egg size was larger than that previously described for the same turtle species in the other regions. The body condition index of neonates indicated a good use of vitelline reserves. The results indicate the urgent need for strategic actions to conserve and maintain the natural stocks of this relatively vulnerable turtle in the region.
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El Valle de Tafí fue uno de los primeros espacios del Noroeste Argentino habitados por comunidades sedentarias, entre el 200 a.C. y el 900 d.C. Éstas establecieron asentamientos aldeanos de varias hectáreas de superficie, alterando sensiblemente el paisaje mediante la construcción de numerosos conjuntos residenciales, canales de manejo del agua, montículos de limpieza de campos de cultivo y muros de contención del suelo. Los procesos históricos desarrollados en ese milenio fueron explicados desde perspectivas teóricas culturalistas (González y Núñez 1960) y sistémicas (Berberián y Nielsen 1988a), las cuales permitieron establecer una estructura cronológica inicial y las principales estrategias adaptativas para el proceso. Este proyecto intenta abordar el modo en que las estrategias de reproducción doméstica se relacionaron con la estructuración del contexto social más amplio. Interesa particularmente analizar las maneras en que la cultura material (arquitectura residencial, campos agrícolas, entierros, alfarería y bienes de prestigio) fue utilizada en la construcción de la sociedad, enfocándonos en la agencia y la identidad. Es de particular importancia establecer la escala real de acción social involucrada en los procesos y la identidad de los grupos que tuvieron una participación activa en ellos. Los trabajos de campo realizados en el Valle de Tafí han provisto de una gran cantidad de datos que evidencian el desarrollo de una sociedad compleja en el primer milenio d.C.: producción agrícola intensiva, demografía creciente, objetos de prestigio en contextos funerarios e intercambio a larga distancia (González y Núñez 1960, Berberián y Nielsen 1988a y 1988b). Sin embargo las unidades sociales implicadas no parecen haber superado a las relaciones propias de unidades domésticas extendidas. Las excavaciones realizadas por nuestro equipo han mostrado fuertes conexiones entre las estrategias de reproducción social doméstica, producción agrícola fragmentada y rituales a los ancestros, materializados no sólo en contextos funerarios ("cistas") y monumentos monolíticos ("menhires-huancas"), sino también en la arquitectura doméstica. Esta relación fue interpretada como un aspecto central en el desarrollo de las sociedades agrícolas tempranas de sur andino, siendo la base de grupos de parentesco competitivos en luchas sociales y negociaciones políticas permanentes. Esta lógica social permitiría explicar la variabilidad registrada en la materialidad arqueológica. La realización de prospecciones, relevamientos y mapeos de sitios, excavaciones sistemáticas, dataciones absolutas, análisis paleopatológicos sobre restos humanos, estudios cerámicos, líticos y de química de suelos, es esencial no sólo para el incremento del corpus de datos que de luz a estos problemas, sino también para la toma de conciencia social acerca del valor del patrimonio cultural prehispánico, que en el presente se encuentra en riesgo.La concreción de los objetivos de este proyecto aportarán a esclarecer hasta qué punto la materialidad doméstica fue un elemento reproductor de predisposiciones subjetivas de la acción (habitus), cómo se relacionaron las viviendas a los sectores de cultivo, en qué forma los emplazamientos productivos modificaron el paisaje y esto repercutió en la propiedad de los medios productivos. Considerando que Tafí fue uno de los primeros valles intermontanos del Noroeste Argentino habitado por comunidades agricultoras, y que este ámbito geográfico significa un lugar de paso obligado entre las yungas orientales y los valles semiáridos y la puna, un profundo estudio de su arqueología podría proveer una mirada sobre la historia del desarrollo cultural surandino. Esta área geográfica es una clave para entender no sólo la historia de los grupos locales sino también el desarrollo y la interacción en un área mayor que se extiende más allá de lo Andes, en Chile.
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n.s. no.16(1983)
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Leptodactylus(Lithodytes) lineatus (Schneider, 1799) is an Amazonian leaf litter frog considered rare or uncommon in several studies on anuran communities. Despite being a widely distributed frog in Amazonian forests, knowledge of the biology and ecology of this species is relatively scarce. This species has been reported to live in association with leaf-cutter ant nests (Atta spp.) during the breeding period. In this paper we present data on the seasonality of this species and some reproductive information gathered at a locality of Rondônia state, northwestern Brazil. Field work was carried out between April 2001 and March 2002, with the use of pitfall traps with drift fences as a survey method. Leptodactylus (L.) lineatus had a higher capture frequency in this locality compared to that of other studies carried out in other Amazonian localities, possibly because this species has secretive habits, such as calling and breeding from nests of leaf-cutting ants, and are difficult to find during visual encounter surveys. The breeding period occurs between October and March. Calling males and egg-bearing females were found between September and February and juvenile recruitment occurred mainly from the end of the rainy season to the beginning of the dry season (February to June). Males and females show sexual dimorphism in SVL, females being significantly larger than males. The number of ovarian eggs per female varies from 110 to 328 and analyses indicate that there is a significant correlation with SVL.
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The results presented in this paper clearly indicate that precocene and azadirachtin are effective inhibitors of moulting and reproduction in the hemipteran Rhodnius prolixus. The time of application is important and only applications of these substances early in the intermoulting period cause their effects in nymphs. The inhibition of moulting is fully reversed by ecdysone therapy. Precocene and azadirachtin also affected drastically the oogenesis and egg deposition in this insect. Precocene-induced sterilization is reversed by application of juvenile hormone III. However, this hormone is unable to reverse the effect of azadirachtin on reproduction. Ecdysteroid titers in nymphs and adult females are decreased by these treatments. In vitro analysis suggest that precocene and azadirachtin may act directly on the prothoracic glands and ovaries producing ecdysteroids. Based on these and other findings the possible mode of action of these compounds on the development and reproduction of Rhodnius prolixus is discussed.
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Proallatotoxins, and particularly preconcenes, are exceptionally promising models for studying Rhodnius prolixus physiology and for comparison with other natural compounds with anti-hormonal activities. Effects of preconcenes on feeding, development and reproduction of R. prolixus are being detailed. The precocenes reveal significant effects on feeding, moulting cycle (inducing precocious metamorphosis and ecdysial stasis), and reproduction of these insect. The mechanism of action of proallatotoxins was discussed based on the corpus allatum cytotoxic effect and on the ecdysteroid biosynthesis in prothoracic glands and ovaries. Further studies of these compounds on R. prolixus are need and will hopefully reveal other unesplored points regarding the action of the proallatotoxins on insects.
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The authors give the first description of evangelicalism in Switzerland using representative data. It is shown that evangelicalism can be conceived of as a "milieu" which is characterized by certain structural and cultural traits, boundaries and high internal communication. The relative success of the evangelical milieu compared to other religious milieus is explained by its remarkable ability to retain its own numerous offspring, while on the other hand providing a "religious product" that is also attractive to people without an evangelical familial background. Les auteurs utilisent des données représentatives afin de faire, pour la première fois, une description de l'évangélisme en Suisse. Ils montrent qu'on peut parler de l'évangélisme comme d'un "milieu'' qui se caractérise par certains attributs structurels et culturels, des frontières et une communication interne élevée. Le succès relatif du milieu évangélique comparé à d'autres milieux s'explique par sa capacité remarquable à retenir les enfants de ses membres dans le mouvement tout en offrant un "produit religieux'' attractif aux personnes sans arrière-fond évangélique.
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The control of Aedes aegypti is impaired due to the development of resistance to chemical insecticides. Insect Growth Regulators (IGR) exhibit distinct mechanisms of action and are considered potential vector control alternatives. Studies regarding the effects of sublethal IGR doses on the viability of resulting adults will contribute to eval-uating their impact in the field. We analyzed several aspects of Ae. aegypti adults surviving exposure to a partially lethal dose of triflumuron, a chitin synthesis inhibitor. A highly significant difference in the proportion of males and females was noted in the triflumuron-exposed group (65.0% males) compared to the controls (50.2% males). Triflumuron affected adult longevity, particularly for females; after 16 days, only 29.2% of males and 13.8% of females were alive, in contrast with 94% survival of the control mosquitoes. The locomotor activity was reduced and the blood-feeding ability of the treated females was also affected (90.4% and 48.4% of the control and triflumuron-exposed females, respectively, successfully ingested blood). Triflumuron-surviving females ingested roughly 30% less blood and laid 25% fewer eggs than the control females. The treated males and females exhibited a diminished ability to copulate, resulting in less viable eggs.
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Despite evidence for the important role of oestrogens in the aetiology and pathophysiology of chronic immune/inflammatory diseases, the previous view of an unequivocal beneficial effect of oestrogens on RA compared with a detrimental effect on SLE has to be reconsidered. Likewise, the long-held belief that RA remits in the majority of pregnant patients has been challenged, and shows that only half of the patients experience significant improvement when objective disease activity measurements are applied. Pregnancies in patients with SLE are mostly successful when well planned and monitored interdisciplinarily, whereas a small proportion of women with APS still have adverse pregnancy outcomes in spite of the standard treatment. New prospective studies indicate better outcomes for pregnancies in women with rare diseases such as SSc and vasculitis. Fertility problems are not uncommon in patients with rheumatic disease and need to be considered in both genders. Necessary therapy, shortly before or during the pregnancy, demands taking into account the health of both mother and fetus. Long-term effects of drugs on offspring exposed in utero or during lactation is a new area under study as well as late effects of maternal rheumatic disease on children.
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Effect of gossypol on survival and reproduction of the zoophytophagous stinkbug Podisus nigrispinus (Dallas). Gossypol is a sesquiterpene aldehyde found in cotton plants conferring resistance against herbivory. Although the effect of this sesquiterpenoid on insect pests of cotton is known, the interaction of this compound with zoophytophagous predators such as Podisus nigrispinus (Dallas) (Hemiptera, Pentatomidae) has not been studied so far. Thus, the objective of this study was to evaluate the effect of the purified gossypol on nymphs and adults of P. nigrispinus. Nymphs and adults of this predator were fed on Tenebrio molitor pupae and supplemented with solutions of gossypol at concentrations of 0.00, 0.05, 0.10, and 0.20% (w/v) during the nymphal and adult stages or, only during the adult stage of P. nigrispinus. The nymphal stage of the predator was, on average, two days longer when suplemmented with gossypol. Emerged adults had lower fecundity and egg hatching, especially at the highest gossypol concentration (0.20%) ingested during the nymphal and adult stages. However, this predator was not affected when it ingested the compound only during the adult stage. P. nigrispinus can have delayed nymphal development and lower reproductive performance when ingesting the gossypol during the nymphal and adult stages, but only at higher concentrations of gossypol than that produced by cotton plants.
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Nesting and use of pollen resources by Tetrapedia diversipes Klug (Apidae) in Atlantic Forest areas (Rio de Janeiro, Brazil) in different stages of regeneration. The nesting in trap-nests and use of pollen sources in larval food by Tetrapedia diversipes Klug, 1810 (Apidae) was compared between regenerating areas of Atlantic Forest. The study was conducted between April 2008 and October 2009 at União Biological Reserve, Rio de Janeiro, Brazil. T. diversipes nested in 66 trap-nests and showed a peak of nesting during the months of highest rainfall. The most frequent pollen type in brood cells during the wet season was Dalechampia sp. 1. During the dry season, the type Ludwigia sp. was the most frequent, followed by Dalechampia sp. 2. The high frequency of Dalechampia and Ludwigia species in the larval food, observed in both habitats and in the two seasons could be considered relevant for T. diversipes, suggesting highly selective diet based primarily on two plant species unrelated, but similar in size of pollen grains.