Measurement of the ratio of inclusive cross sections sigma(p(p)over-bar -> Z plus b-quark jet)/sigma(p(p)over-bar -> Z plus jet) at root s=1.96 TeV

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Precision Measurement of the Ratio B(t -> Wb)/B(t -> Wq) and Extraction of V-tb

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Measurement of the relative branching ratio of B-s(0) -> J/psi f(0)(980) to B-s(0) -> J/psi phi

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Optimisation of the glycerol-to-ornithine molar ratio in the feed medium for the continuous production of clavulanic acid by Streptomyces clavuligerus

Amino acids are well metabolized by Streptomyces clavuligerus during the production of clavulanic acid using glycerol as main carbon and energy source. However, only a few amino acids such as arginine and ornithine are favorable for CA biosynthesis. The aim of this work was to optimize the glycerol:ornithine molar ratio in the feed medium containing only these compounds to maximize CA production in continuous cultivation. A minimum number of experiments were performed by means of a simple two-level full-factorial central composite design to investigate the combined effect of glycerol and ornithine feeding on the CA concentration during the intermittent and continuous process in shake-flasks. Statistical analysis of the experimental data using the response surface methodology showed that a glycerol-to-ornithine molar ratio of approximately 40:1 in the feed medium resulted in the highest CA concentration when fermentation was stopped. Under these optimized conditions, in bench-scale fermentor runs, the CA concentration reached more than double the concentration obtained in shake-flasks runs. (C) 2009 Elsevier B.V. All rights reserved.

Perspectivas para a criação massal de Iphiseiodes zuluagai Denmark & Muma (Acari: Phytoseiidae)

Iphiseiodes zuluagai Denmark & Muma é um importante predador de Brevipalpus phoenicis (Geijskes) em citros no Brasil. O emprego de Tyrophagus putrescentiae (Schrank) como fonte de alimento para I. zuluagai em criações de laboratório foi investigado a 25,5 ± 0,5ºC, 88 ± 7% UR e fotofase de 12h. Inicialmente os níveis de oviposição do predador alimentado com ovos, estágios pós-embrionários mortos ou estágios pós-embrionários vivos de T. putrescentiae foram avaliados durante 10 dias. A taxa diária de oviposição foi de 1,3 ovo/ fêmea quando estas foram alimentadas com ovos de T. putrecentiae; 0,7 ovo/ fêmea quando estas foram alimentadas com estágios pós-embrionários mortos e cerca de 0,2 ovo/ fêmea quando alimentadas com estágios pós-embrionários vivos. Posteriormente, elaborou-se a tabela de vida de I. zuluagai, oferecendo-se como alimento ovos de T. putrescentiae. Os estágios imaturos foram observados a cada 8h, para determinar a duração correspondente. Na fase adulta, os ácaros foram observados a cada 24h, para se determinar os parâmetros reprodutivos. A capacidade de aumento populacional (r m) foi de 0,11 fêmea/ fêmea/ dia; resultando em uma razão finita de aumento de 1,11 (l). A taxa líquida de reprodução (R0) foi de 7,1 fêmeas/geração, com um tempo de geração de 18,6 dias. Os resultados obtidos mostram que T. putrescentiae é uma fonte de alimento favorável ao desenvolvimento de I. zuluagai.

Habitat associations of small mammals in southern Brazil and use of regurgitated pellets of birds of prey for inventorying a local fauna

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Developmental biology, polymorphism and ecological aspects of Stiretrus decemguttatus (Hemiptera, Pentatomidae), an important predator of cassidine beetles

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Effects of the seed predator Acanthoscelides schrankiae on viability of its host plant Mimosa bimucronata

Seeds of Mimosa bimucronata are heavily infested (pre-dispersal predation) by the bruchid beetle Acanthoscelides schrankiae in Brazil. In this study, firstly we set up experiments to assess seed germination under seven and six different light and temperature regimes, respectively, and then we evaluated the ability of seeds to germinate after predation. We tested the hypothesis that the non-predated seeds from infested fruits may respond differently when set for germination than those seeds of non-infested fruits. We also hypothesized that predation may increase the production of unviable seeds. Seeds under 18 hours of light presented the highest percentage of germination, and the alternating temperature 20-30 degrees C was considered as optimum for germination (abnormal seedlings were not considered as a successful germination). Germination of seeds from non-infested fruits was significantly higher than germination of non-predated seeds from infested fruits, and predation also caused a significant increase in the proportion of dead seeds. Our results also show a positive correlation between proportions of unviable seeds and predated seeds. These results demonstrated that seeds of M. bimucronata are strongly affected by predation because predated seeds did not germinate and non-predated seeds had their viability reduced when located in infested fruits, supporting our hypothesis.

Second-order statistics for equal gain and maximal ratio diversity-combining reception

Exact and closed-form expressions for the level crossing rate and average fade duration are presented for equal gain combining and maximal ratio combining schemes, assuming an arbitrary number of independent branches in a Rayleigh environment. The analytical results are thoroughly validated by simulation.

THAUMATOMYRMEX STRIPS MILLIPEDES FOR PREY - A NOVEL PREDATORY BEHAVIOR IN ANTS, AND THE 1ST CASE OF SYMPATRY IN THE GENUS (HYMENOPTERA, FORMICIDAE)

We describe, for the first time, the predatory behaviour of Thaumatomyrmex ants on millipedes of the family Polyxenidae, based on field observations of T. atrox and a field and laboratory study of T. contumax. The capture of the prey and the removal process of its body-covering setae by the ants before they eat the millipede are described. This specialized behaviour in at least two species of the genus, belonging to two distinct groups of species, indicates a general trend in Thaumatomyrmex. We coupled this study with a comparative morphological analysis of the mouthparts and digestive tube of these and other Thaumatomyrmex species. Also, we report the first case of sympatry in the genus, which suggests that Thaumatomyrmex includes several species. and not only one highly variable taxon, as hypothesized earlier.

Modeling the age-specific per capita growth and reproduction of Rhizobius lophanthae (Col: Coccinellidae)

A per capita model for the growth, development and reproduction of the coccinellid predator Rhizobius lophanthae (Blaisd) feeding on the oleander scale (Aspidiotus nerii Bouche (Homoptera: Diaspididae)) was developed. A thermal threshold for development of 9.4 degrees C was found. Under conditions of unlimited food, the relationship of mass at time t+1 to that at t (in days at 25 degrees C) suggests an 8.7 percent growth rate per mg larvae per day at 25 degrees C. An adult female beetle produces approximately 20 eggs per day while consuming an average of 8.5 scales/day. This is approximately 2.16 eggs per scale consumed above the maintenance level of 1.88 scales per day. More precisely, this compensation point is 0.12 mg of prey/mg of predator/day at 25 degrees C and the egestion rate is 1 - beta = 0.63.

THE EFFECT OF RECENT DIET ON PREY ODOR DISCRIMINATION BY JUVENILE TEGU LIZARD, TUPINAMBIS-TEGUIXIN (SAURIA, TEIIDAE)

Teiid lizards are intesive foragers supposed to rely lagerly on chemoreception for prey detection, an ability that can be modified by previous feeding experiences. We investigated the ability of juvenile lizards, Tupinambis teguixin, in discriminate prey from non-prey odors as well as the effects of recent diet on these ability. Tegu lizards were able to discriminate prey odors and this ability probably is inate. The effect of recent diet was analysed through optimal foraging models and our results does not support in a broad sense the predictions made by theoretical models.

Caries resistance of lased human enamel with Er : YAG laser - morphological and ratio Ca/P analysis

Objective: In vitro analysis of caries resistance of dental enamel under caries simulation after irradiation with Er:YAG laser. Background Data: More susceptible to caries development spots at adjacent hard tissues from cavity preparations of dental tissues using burrs or lasers are quite common. Methods: Thirteen caries-free third permanent human molars were distributed as follows: G1: sound control and caries control; G2: Er:YAG 100, 200, 300, or 400 mJ/ 10 Hz/ 3 sec.; G3: the same parameters of G2 followed by artificial caries simulation, through dynamic model of demineralization and remineralization (DE/RE). Caries resistance analysis was evaluated through scanning electron microscopy (SEM) and Ca/P rate (X-Rays spectroscopy - EDX). Results: Photomicrographs showed that the Er:YAG laser created craters with rough aspect which became more evident as the energy per pulse was increased, but without change of regular morphology of enamel prisms. Significant statistical changes among the irradiated and control groups was observed considering the Ca/P ratio. Conclusion: Irradiated groups showed higher caries resistance than control groups. However, it is not possible to affirm that the enamel surface accidental irradiation could be a benefit to caries resistance for other situations can be considered, as biofilm deposit, which could increase the caries susceptibility.