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Diversidade dos Braconidae (Hymenoptera: Ichneumonoidea) em remanescentes de Mata Atlântica Ombrófila Densa
(Universidade Federal de São Carlos, 2006-05-31) Yamada, Magda Viviane; Dias, Angélica Maria Penteado Martins; https://lattes.cnpq.br/8637344058859147
This work aimed to describe the Braconidae diversity in remainders of the Atlantic Rain Forest in Brazil and to verify if there are patterns of distribution along a latitudinal gradient and at low and high altitudes. Since the Braconidae community might be considered an exception to the established patterns of diversity and the scarceness of studies focusing the group, they were chosen in this study. Besides, they have a very important role in the balance of the ecosystems; they are natural enemies of phytophagous insects considered crop pests. In order to sample the largest proportion of the resident fauna in the sites three sampling techniques were used; two passive (Malaise and Moericke traps) and one active ("sweeping" the vegetation). The sample efforts and periods were standardized to avoid possible seasonal influences. This work is part of the BIOTA/FAPESP Project: "Richness and Diversity of Hymenoptera and Isoptera along a latitudinal gradient in the Atlantic forest - the Eastern Brazilian Rain Forest" and included 18 sample sites from the Northeast to the Southern Brazil. The Richness Index and Relative Density were used to determine the conservation status of the forest remainders sampled. The Braconidae community did not demonstrate a pattern of distribution along the latitudinal gradient and also no predominant distribution in the two altitude classes was found; however, the sites in higher altitudes showed a more homogeneous and diverse fauna. Many of the entomofauna surveys in Neotropical region allowed the description of new species and new records; here, we present three new records and the description of four new species of Alabagrus Enderlein (Braconidae, Agathidinae) to Brazil. It is suggested that Peruíbe (SP), Linhares (ES), Porto Seguro (BA), Santa Luzia de Itanhy (SE), Recife (PE) and João Pessoa (PB) are places under influence of anthropic activities, and Intervales (SP) and Nova Iguaçu (RJ) are the most preserved. Doryctinae and Alysiinae are suggested as bioindicators of disturbance and environmental conservation, respectively. Cheloninae, Doryctinae, Hormiinae and Rogadinae were assigned as indicators for studies on anthropic impacts assessment in the Atlantic Rain Forest biome due to their wide distribution. The fragment size was not correlated with the abundance and richness of Braconidae specimens. The more efficient sampling method was "sweeping" the vegetation for the Braconidae fauna.
Extensões ao protocolo de comunicações EPCGloboal para tags Classe 1 utilizando autenticação com criptografia de baixo custo para segurança em identificação por radiofreqüência
(Universidade Federal de São Carlos, 2006-05-31) Mota, Rafael Perazzo Barbosa; Zorzo, Sérgio Donizetti; https://lattes.cnpq.br/2523715806470871
EPCGlobal communication protocol for RFID (Radio Frequency Identification) does not ensure security and privacy for its system users. This fact makes possible several kinds of security problems on RFID technology usage justifying that security mechanisms should be added to communication protocol preserving the existing standards. This work proposal is based on communication authentication usage making use of low-cost cryptography with the TEA algorithm. The proposed mutual authentication mechanism was specified and proved using BAN logic. All protocol specification has considered the EPCGlobal standard for Class 1 tags as base adding security and privacy extensions to data communication to get protection against several attacks. The results from this work include an authentication protocol formal specification with cryptography allowing this way the protocol standardization using as base the current Class 1 protocol.
Balanço energético e seletividade alimentar de Hyphessobrycon eques e Serrapinnus notomelas (Pisces, Characiformes)
(Universidade Federal de São Carlos, 2006-05-31) Matheus, Fábio Eduardo; Rocha, Odete; https://lattes.cnpq.br/7577441794992601
The trophic ecology and bioenergetic aspects of most small fishes were not yet investigated, although they are important components in the ictiofauna, largely contributing to the richness of species and to the energy flow in aquatic ecosystems. The energy budgets and the food selectivity of two species of small fishes, Hyphessobrycon eques and Serrapinnus notomelas, were analysed. Natural populations were sampled from Monjolinho River, São Carlos, SP, in the period between September to December 2005, and January to April 2006. Food selectivity experiments and energy budgets experiments were performed in the laboratory using planktonic and benthic invertebrates as food items. Food selection was evaluated by Paloheimo index, by calculating the normalized forage ratio. Both species had preference and positive selection for the dipteran larvae Aedes aegypti, Chironomus xanthus and Chaoborus sp., as well as for the cladocerans Daphnia laevis and Ceriodaphnia silvestrii. They presented negative selection or absence of selection for Hyalella meinerti and Cypricercus mucronata. The positive selection of both species of fishes for the larvae of Aedes aegypti evidenced that they have potential to be used in the biological control on dengue disease epidemies. The results obtained from the energy balances revealed that S. notomelas has higher consumption and assimilation rates than H. eques, however its production efficiency is lower as a consequence of higher metabolic expenditures. On average the production efficiency was 53% for H. eques and 22% for S. notomelas. The values obtained for the instantaneous net production efficiency of both species were higher than those reported in the literature for carnivorous fishes (20%) and also higher than those reported for natural populations of small fishes in tropical regions.
Um novo estimador exponencial por partes da curva de sobrevivência: um estudo comparativo
(Universidade Federal de São Carlos, 2006-05-31) Moraes, Fabíola Eugênio Arrabaça; Louzada Neto, Francisco; https://lattes.cnpq.br/0994050156415890
In this work we revise the main basic concepts on survival analysis and reliability. We present the most known nonparametric estimators of the survival function in the presence of censured data. Their estimates are calculed and compared in an real data set on human renal transplants. We point some problems that are not usually considered in the structure of these estimators. As consequense of such problems we can observe possible distortions in the estimates the direction of sub or over estimating the main characteristics of interest. Some alternatives are pointed out for finding lesse vulnerable estimators. Moreover, we propose a new modified piece wise exponential estimator, pointing out its properties.