Diversity and genetic population structure of the Brazilian sharpnose shark Rhizoprionodon lalandii

Similar to many small, range-restricted elasmobranchs, the Brazilian sharpnose shark (Rhizoprionodon lalandii) is listed as 'data deficient' by the International Union for the Conservation of Nature (IUCN). Data on stock assessment and sustainability are scarce, and there is no information on population structure. This constitutes a management problem because this shark comprises approximately 50% of the catch of small coastal sharks in Brazil. In this study, populations of R. lalandii distributed from the Caribbean to southern Brazil were investigated using sequences from the mitochondrial DNA control region. Analysis of molecular variance revealed strong structuring between population samples from the Caribbean and those from the Brazilian coast (F{cyrillic}ST=0.254, P<0.0001). Significant differences in the rates of genetic diversity between these major areas were also detected. The observed levels of population structuring are likely to be driven by female phylopatry. Therefore, the identification of both mating and nursery areas with parallel ban/restriction of fishing in these areas may be critical for the long-term sustainability of these populations. © 2013 John Wiley & Sons, Ltd.

Nesting architecture and population structure of the fungus-growing ant Cyphomyrmex transversus (Formicidae: Myrmicinae: Attini) in the Brazilian coastal zone of Ilheus, Bahia

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Genetic diversity and population structure of pumas (Puma concolor) in southeastern Brazil: implications for conservation in a human-dominated landscape

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

Genetic Structure of Populations of the Rice-Infecting Pathogen Rhizoctonia solani AG-1 IA from China

Sheath blight disease (SBD) on rice, caused by Rhizoctonia solani AG-1 IA, is one of the most devastating rice diseases on a global basis, including China (in Eastern Asia), the world's largest rice-growing country. We analyzed the population genetics of nine rice-infecting populations from China using nine microsatellite loci. One allopatric population from India (Southern Asia) was included in the analyses. In total, 300 different multilocus genotypes were found among 572 fungal isolates. Clonal fractions within rice fields were 16 to 95%, suggesting that sclerotia were a major source of primary inoculum in some fields. Global Phi(ST) statistics (Phi(ST) = 42.49; P <= 0.001) were consistent with a relatively high level of differentiation among populations overall; however, pairwise comparisons gave nonsignificant R(ST) values, consistent with contemporary gene flow among five of the populations. Four of these populations were located along the Yangtze River tributary network. Gene flow followed an isolation-by-distance model consistent with restricted long-distance migration. Historical migration rates were reconstructed and yielded values that explained the current levels of population subdivision. Except for one population which appeared to be strictly clonal, all populations showed evidence of a mixed reproductive mode, including both asexual and sexual reproduction. One population had a strictly recombining structure (all loci were in Hardy-Weinberg equilibrium) but the remaining populations from China and the one from India exhibited varying degrees of sexual reproduction. Six populations showed significant F(IS) values consistent with inbreeding.

Bond strengths, degree of conversion of the cement and molecular structure of the adhesive-dentine joint in fibre post restorations

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Manipulation of fire ant density, Solenopsis spp., for short-term reduction of Diatraea saccharalis larval densities in Brazil

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

The Gerasimov-Drell-Hearn Sum Rule and the Spin Structure of the Proton

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

Gluconeogenesis and glucose replacement rate during long-term fasting of Japanese quails

Gluconeogenic activity and kinetic parameters of glucose metabolism were estimated during the different phases of prolonged food deprivation in quails. Gluconeogenic activity, estimated from the rate of increase of incorporation of (HCO3-)-C-14 into circulating glucose, was significantly higher in fasted quails than in fed birds, whatever the period of food deprivation. However, gluconeogenic activity during phase II, although higher than in the fed state, was significantly lower than in quails fasted for 2 days (phase I) or in those on the final (phase III) period of starvation. Gluconeogenic activity did not differ significantly in birds from phases I and III. Rates of glucose replacement, estimated with [6-H-3]-glucose, were very high (20.5 mg . kg(-1). min(-1)) in fed quails and were markedly reduced (to about 42% of fed values) by fasting, no difference being observed between quails fasted for 2 and 5 days. Because of the poor condition of the birds, glucose replacement rates could not be measured during phase III. The present data are the first to provide direct evidence for the changes in gluconeogenesis which occur during prolonged food deprivation.

Basis sets applied to the theoretical study of the vibrational structure of hexaaquaaluminum(III) ion

Gaussian basis sets were developed with the Generator Coordinate Hartree-Fock (GCHF) method for the atoms from H (14s), O (23s16p), and Al (29sl9p) in the ground state. These basis sets were then contracted to 3s (12,1,1), 5s3p (18,2,1,1,1/14,1,1), and 7s5p (20,3,2,1,1,1,1/14,2,1,1,1) for H, O and Al atoms, respectively, by a standard procedure. The quality of contracted basis sets in molecular calculations was evaluated through studies of the total and orbital (epsilon(HOMO) and epsilon(HOMO-1)) energies at the HF level for the hexaaquaaluminum(III) ion, [AI(H(2)O)(6)](3+). For the O atom, the 5s3p was supplemented with d polarization function and it was used in combination with 3s, and 7s5p for H and Al atoms was used to the theoretical interpretation of the Infrared (IR) spectrum of hexaaquaaluminum(III) ion. The calculations of the IR-spectrum were also performed at the HF level and it showed that the basis sets obtained with the aid of GCHF method lead to the selection of useful contracted Gaussian basis sets for the theoretical study of vibrational property of ionic specie of our interest. (C) 2004 Elsevier B.V. All rights reserved.

Microhabitat and plant structure of Batrachospermum (Batrachospermales, Rhodophyta) populations in four streams of São Paulo State, southeastern Brazil

Microhabitat and plant structure of seven Batrachospermum populations (four of Batrachospermum delicatulum (= Sirodotia delicatula), one of Batrachospermum macrosporum and two of the 'Chantransia' stage), including the influence of physical variables (current velocity, depth, irradiance and substratum), were investigated in four streams of São Paulo State, southeastern Brazil. The populations of B. delicatulum and the 'Chantransia' stage occurred under very diverse microhabitat conditions, which probably contributes to their wide spatial and seasonal distribution in Brazilian streams. Results suggest branch reconfiguration as a probable mechanism of adaptation to current velocity based on the occurrence of: (i) B. macrosporum (a large mucilaginous form with presumably little ability for branch reconfiguration) under lower current velocity than B. delicatulum; (ii) only dense plants in populations with high current velocities (> 60 cm s-1), whereas 53-77% of dense plants were seen in populations exposed to lower currents (< 40 cm s-1); (iii) positive correlations of plant length with internode length in populations under low current velocities and negative correlation in a population with high velocity (132 cm s-1); and (iv) negative correlations of current velocity with plant diameter and internode length in a population under high flow. This study, involving mainly dioecious populations, revealed that B. delicatulum displayed higher fertilization rates than B. macrosporum. A complementary explanation for a dioecious species to increase fertilization success was proposed consisting of outcrossing among intermingled male and female adjacent plants within an algal spot.

Population structure of the seabob shrimp Xiphopenaeus kroyeri (Heller, 1862) (Crustacea: Penaeoidea) in the littoral of São Paulo, Brazil

The population structure of the penaeidean shrimp Xyphopenacus kroyeri was studied in Ubatuba Bay, Ubatuba, Sd̃ao Paulo, Brazil. The period and site of juvenile recruitment were monitored using a monthly sampling design with eight fixed areas (transects) from September 1995 to August 1996. The population structure was assessed using size frequency distributions (based on carapace length) for each month and sampling area. Females were significantly larger than males, suggesting a differential growth between sexes. The very low occurrence of large adults in the Bay can be related to offshore migration for reproduction. Recruitment occurred throughout the year, with a peak during the summer, when the highest recruitment rates were obtained along inshore transects. The present investigation revealed valuable information on the biology of the species mainly in the study region, which is considered a nursery ground for juveniles of X. kroyeri. The species showed an important variation from the typical life cycle that it is assumed to hold over its entire range and X. kroyeri should be classified as having a life cycle different from that proposed previously in the literature, i.e. the juveniles prefer inshore areas instead of estuaries. Some suggestions for the seabob fishery management are proposed as an alternative for minimising the impact during the harvest period and adjusting the protection schedule.

Shading effects on community composition and food web structure of a deforested pasture stream: Evidences from a field experiment in Brazil

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

Short-term effects of visitor trampling on macroinvertebrates in karst streams in an ecotourism region

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

The structure of non-abelian kinks

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

Short and long-term repercussions of the experimental diabetes in embryofetal development

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