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Avaliação da diversidade e estrutura genética de Micoureus paraguayanus (Didelphidae) através do marcador mitocondrial d-loop no Parque Estadual Morro do Diabo e em fragmentos de Mata Atlântica adjacentes
(Universidade Federal de São Carlos, 2009-06-25) Cattony Neto, Pedro de Queiroz; Rodrigues, Fernando Pacheco; https://lattes.cnpq.br/1351286774058975; https://lattes.cnpq.br/8154585078632750
The dynamics of use of land in urban and agricultural areas has led to destruction and fragmentation of ecosystems. It has been related to the increase of susceptibility of natural populations to extinction due to increase of isolation between populations and reduction of population size. To evaluate the effect of the recent habitat fragmentation on the genetic diversity of natural populations, we will analyze the diversity and genetic structure of populations of the wooly mouse opossum Micoureus paraguayanus (Marsupialia: Didelphimorphia) in the Parque Estadual Morro do Diabo (SP) and in bush fragments in its surroundings. For this purpose, we used the control region (D-Loop) to examine population structure and dynamics in fragmented forest habitats. We found low values of haplotypic and nucleotidic diversity when compared to values from previous works with marsupials in fragmented areas. We found values of diversity of 0.28 and 0.0022% respectively. Besides that, there was a correlation between continuous cultivated lands distance and number of exclusives haplotypes. The AMOVA test showed no genetic structure between fragments, however, Fst values indicated significant genetic differentiation to Santa Tereza and Ponte Branca when compared with all the others fragments. These are between the smallest areas evaluated in this study and the differentiation indicates that the recent fragmentation suffered by these patches could be responsible for the changes in the genetic composition of these populations.
Linha de base cumulativa e sistema de conseqüências no ensino informatizado de leitura
(Universidade Federal de São Carlos, 2009-06-25) Cordioli, Raquel Baccarin Ribeiro; Souza, Deisy das Graças de; https://lattes.cnpq.br/4404800720856419; https://lattes.cnpq.br/0284918535550702
The study evaluated two versions of a computerized program for teaching reading skills (de Souza e de Rose, 2006) which was intended to teach the relations between sets of stimuli consisting of a written word, a picture and a spoken word. Although developed to ensure that the apprentice advance at his own pace, the steps of this program were designed to teach fixed sets of three words. This meant that until he reaches the criterion of 100% of hits for the whole set, the participant keeps repeating the same step. This feature may require a number of unnecessary steps, and also result in damage to the motivation, as the participant can judge he is not progressing. The objective of this study was to determine whether a new organization of the steps of teaching, including only words whose relations are not mastered by the participant, could expedite the conclusion of the program. Additionally, it embedded a virtual album of stickers with the function of providing feedback to the learner of his performance. The stickers were presented as a consequence to the establishment of relations between the stimuli of each of the sets. In Study I the new procedure was introduced to five participants who were being exposed to the original persion and the results showed an acceleration in the pace of learning for four of the five participants. In Study II, the assessment of reading is held throughout the cumulative baseline and not only for last 15 words of the unit, as determined in previous procedures. The program was completed when the participant completed the reading of 60 words. Eleven students with different entry repertoires in reading completed the Study II. The data were compared to 14 students with similar repertoire that had completed the original version. The new version resulted in a decrease in the total number of sessions for most participants. A more pronounced decrease was observed in achieving the first half of the expected repertoire in this study. Another result observed was greater number of words taught by the intermediary sessions. The new contingencies of teaching led to a higher individual progress, greater variability in the content taught and can accelerate the progress of the participant.
Propriedades de transporte de spins polarizados em heteroestruturas semicondutoras
(Universidade Federal de São Carlos, 2009-06-25) Pacobahyba, Luiz Henrique; Bittencourt, Antonio Carlos Rodrigues; https://lattes.cnpq.br/1105838755157684; https://lattes.cnpq.br/8694960488322263
In this work we used the technique of scattering matrix to calculate the transmissivity of polarized spins in a semiconductor symmetrical double-barrier heterostruture. The dynamics of carriers is described by effective mass approximation applied to models of Dresselhaus and Bychkov-Rashba. In the former case, the hamiltonian was studied in its full form, free of approximations. Both models describe interactions of type Spin-orbit, which is basically a coupling between the orbital angular moment of the electron with its magnetic moment of spin. This type of coupling as a consequence creates a splitting of some levels of energy, initially degenerate, resulting in a spectrum of energy more complex than that obtained without taking it into account such interactions. The transmissivity is calculated as a function of some parameters, for the type InAs=GaSb=InAs=GaSb=InAs. All results are compared with literature, and provide new information about the systems. The effects of spin-orbit interactions of Rashba and Dresselhaus show is very favorable to engineering in the manufacture of .lter spin and spintronic devices, as well as the injection of spin in quantum wells and semiconductor detectors based on non-magnetic asymmetric double barrier.