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Aspectos da biologia, variabilidade genética e estrutura sociogenética dos agregados de Digelasinus diversipes (Kirby, 1882) (Hymenoptera: Agridae)
(Universidade Federal de São Carlos, 2003-07-29) Boraschi, Daniele; Del Lama, Marco Antonio; https://lattes.cnpq.br/7198095288825585; https://lattes.cnpq.br/2932860205914526
Symphyta is a suborder of Hymenoptera, which presents primitive characters, like absence of constriction at the base of the abdomen. Symphyta larvae are phytophagous and feed gregariously, causing damage to agricultural crops, ornamental plants and forests stands, especially in temperate zones. In this group researches focus mainly on ecological aspects related to pests control. There are few data about population genetic structure, and studies about genetic variability exhibit disagreeable data. This study attempts to elucidate some aspects of the biology of Digelasinus diversipes, a Neotropical Symphyta with active larvae from November until March which host in Eugenia glazioviana (Myrtacea) trees, where cocoon masses can be found. Genetic variability and population structure were measured by allozymic analyses through starch gel electrophoresis. Cocoon masses were collected in 2000 and 2001, in two areas of the Estação Ecológica Jataí (Luiz Antônio, SP 21º25 S, 47º50 W). Field observations evidenced i) Digelasinus diversipes larvae disperse during foraging, among neighboring trees; ii) larvae from different ovipositions associate to cocoon mass communal construction, observation corroborated by the low relatedness coefficient among individuals of cocoon mass; iii) adults are shortlived; males are smaller than females, which emerge with all eggs matured for fecundation and/or oviposition; iv) the secondary sex ratio, measured by individuals emerged at laboratory, are female-biased. Electrophoretic analyses reveal high levels of average heterozigosity (Hobs = 0.094±0.025SE) for this species, contrasting with previous data for other Hymenopteran species. There were no significant levels of inbreeding inside samples, but the population was structured, suggesting low levels of gene flow, a consequence of their low dispersal ability.
Desenvolvimento de um leito vibro-fluidizado e estudos dos coeficientes de transferência de calor de corpos submersos
(Universidade Federal de São Carlos, 2003-07-29) Camargo, Célio Fernando dos Santos; Freire, José Teixeira; https://lattes.cnpq.br/2270677706718167
In this work equipment developments and techniques for aerodynamics and heat transfer studies in a vibro-fluidized bed are presented. The equipment projected and built consists of an acrylic bed with a circular section of 0.12 m diameter and 0.5 m height, with an eccentric mechanism that allowed the amplitude variation, and through the motor speed, variation in the frequency vibration. The aerodynamics study in a vibro-fluidized bed has been carried out through the analysis of the fluidization and standard deviation curves obtained for both systems (conventional and vibrated), in order to verify the pressure drop in the bed and the oscillation around the average, in function of the vibrational frequency and the initial bed height. The bed was constituted of ballotini glass spheres of 700 µm. The global heat transfer coefficient between immersed test body and the bed was obtained from two geometric configurations: cylinder and spheres. For the spherical geometry three different diameters were studied. In both geometries an electric resistances for the bodies heating was used. The local heat transfer coefficient was obtained from a similar cylinder to the one described previously, however equipped with a platinum sensor. This sensor consisted of a quartz piece with a fine platinum film linked to an electric circuit that through appropriate equation and monitor software allowed the obtaining of this coefficient. The influence of the superficial air velocity, vibrational frequency, particle size, forms and size of the tests bodies were analyzed. The aerodynamic results showed that, without vibration, the instantaneous pressure had a significant increase with the intensity vibration, with a maximum value in most of the results. The difference for an experimental condition for another one, is the angular area of the cylinder in which this tendency happens for the coefficient. When compared with the bed without vibration, just fluidized it, was verified that the values obtained in this work for the local coefficient have a similar behavior to the ones found in the literature. oscillation observed in the deviation standard curves are independent of the bed height. In the vibro-fluidized beds these oscillation showed a strong dependence on the bed height and on the dimensionless parameter, in the interval of variables studied. The results of the global heat transfer coefficient showed an increase of h, with the imposition of vibrations, with smaller particle size and for larger air velocity, for both studied geometries. When analyzed locally, it was observed that hθ had a significant increase with the intensity vibration, with a maximum value in most of the results. The difference for an experimental condition for another one, is the angular area of the cylinder in which this tendency happens for the coefficient. When compared with the bed without vibration, just fluidized it, was verified that the values obtained in this work for the local coefficient have a similar behavior to the ones found in the literature.