A model for the plankton system of the Broa reservoir, Sao Carlos, Brazil

In this paper a model, called ELLOBO running in STELLA II, was set to describe the plankton system of the Broa reservoir (SP). The three state variables of the model are: phytoplankton, zooplankton, and the fish Astyanax fasciatus. The forcing variables are: temperature, nitrate, phosphorus and solar radiation. The model did not consider the cycling of nutrients inside the reservoir. The results show that: temperature is the principal forcing variable in the phytoplankton dynamic and in the subsequent evolution of the whole system. The zooplankton predation was described by Odum's equation, and there is a strong random component in zooplankton grazing, which was essential for the model, because zooplankton estimates have high variance. One must collect data in a short space of time (maybe daily) to better explain the zooplankton and phytoplankton variation. Validation was performed using simple statistics (arithmetic mean, standard deviation) and the results show concordance between observed and simulated values. Overhead was used to calibrate some parameters and to validate the model. The highest overhead value (5%) imply in the better accordance between estimated and;observed state variables values. We believe this approach in Broa reservoir will provide an useful tool for future research and it could be used comparatively in other continental aquatic ecosystems. (C) 2000 Elsevier B.V. B.V. All rights reserved.

Social and financial aspects of the artisanal fisheries of Middle Sao Francisco River, Minas Gerais, Brazil

The presence or absence of motorized boats, partnerships and multispecies catches characterize the fisheries of Sao Francisco River, Minas Gerais, Brazil. Fishing activity based on 109 interviews, carried out in the wet (high water: February and March) and dry (low water: July and August) seasons, with professional fishermen are described. Aiming to identify the fishery income components, a covariance model was proposed, with the income as the response variable, related to the factors: fishing ground, use of motorized or paddle boat; seasonality; presence of fishing assistant, and the following covariates: capture in weight in the week Frier to the interview, fisherman experience in yrs; and distance (km) travelled for fishing. The results indicated that the main contributions to income were the absence of an engine (because of high price of the fuel), the absence of a partner (because of low capture) and the amount of fish caught by the fishermen.

Diversity and distribution of crustaceans from 13 sheltered sandy beaches along Sao Sebastiao Channel, south-eastern Brazil

The crustacean species composition in the intertidal zones of 13 sheltered unconsolidated marine beaches in south-eastern Brazil is described. Fifty-three crustacean species were collected, adding 46 species to the total reported by previous studies in the same region. Decapods dominated the community, in contrast to exposed sandy beaches where peracarids normally predominate. The species were distributed irregularly among the beaches. Richness varied markedly among sites, and was positively related to a combination of factors such as fine sand grains, high organic matter content, and relatively low silt-clay content. The presence of rock fragments enabled both rocky shore and sandy beach crustaceans to occur oil the same beaches. Richness and abundance of crustaceans showed no clear relationship to sediment grain size and slope, in contrast to the norm for exposed sandy beaches. The dominance of the tanaid Kalliapseudes schubarti in sonic areas may be a result of organic matter pollution in the region. These beaches showed higher species richness than typical sheltered and exposed sandy beaches, indicating that this sheltered, highly heterogeneous seascape is an important area for conservation.

A NEW SPECIES of ISCHNOCNEMA (ANURA) FROM THE SAO FRANCISCO BASIN KARST REGION, BRAZIL

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

Resources Taken to the Nest by Protopolybia exigua (Hymenoptera, Vespidae) in Different Phases of the Colony Cycle, in a Region of the Medio Sao Francisco River, Bahia, Brazil

The present study aimed to identify what resources were taken to the nest by workers of Protopolybia exigua (de Saussure), to verify if there is a relationship between physical factors of weather and phases of colony development and the collection of different resources and also to observe if the wasps carry macerated prey in the crop. The species collected nectar (62.8%), wood pulp for nest building (6.1%), water(2.9%), prey (0.8%) and resin (0.2%). Moreover, workers of P exigua do carry macerated prey in the crop. There was a positive correlation (r = 0.85, p = 0.0004) between the presence of larvae in the nest and the carrying of solid contents in the crop, which provides strong evidence that this species macerates its prey while still in the field, before taking it to the nest. There was positive influence of the temperature on the collection of nectar (r = 0.89, p = 0.0001) and water (r = 0.46, p = 0.0066) and negative influence of relative air humidity on the collection of the same resources (r = - 0.88, p = 0.0001 and r = - 0.37, p = 0.0160, respectively). Luminosity influenced the gathering of water (r = 0.43, p = 0.0089) and Pulp for nest building (r = 0.31, p = 0.0274) and the wind speed did nor influence the collection of any resources. Nectar is the main item taken to the nest during all phases of the colony.

Evaluation of simulated external root resorptions with digital radiography and digital subtraction radiography

Introduction: Root resorption can cause damage in orthodontic patients. Digital subtraction radiography (DSR) is a useful resource for the detection of mineral losses. The purpose of this study was to compare the efficacy of digital radiography (DR) and DSR in detecting simulated external root resorption. Examiner agreement between the 2 techniques was also evaluated. Methods: Root resorptions of various sizes were simulated on the apical and lingual aspects of 49 teeth from 9 dry human mandibles. The teeth were radiographed in standardized conditions. The radiographs were registered with Regeemy Image Registration and Mosaicking (version 0.2.43-RCB, DPI-INPE, Sao Jose dos Campos, São Paulo, Brazil) and subtracted with Image Tool (University of Texas Health Science Center at San Antonio). The subtracted images and the digital radiographs were evaluated by 3 oral radiologists. Results: No statistically significant differences were found for the methods in the detection of apical root resorptions, independently from lesion size, and of lingual resorptions of 1.2 mm or greater. DSR was significantly better than DR for detection of lingual resorptions up to 1 mm. Resorptions less than 0.5 mm were not precisely detected by either method. DSR provided better intraexaminer and interexaminer agreement than did DR. Conclusions: Both methods are precise for detection of apical root resorptions as small as 0.5 mm and lingual resorptions of 1 mm or more. However, DSR frequently performed better than did DR. (Am J Orthod Dentofacial Orthop 2011;139:324-33)

Development of environmental and natural vulnerability maps for Brazilian coastal at Sao Sebastiao in São Paulo State

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

ORGANOCHLORINE PESTICIDE-RESIDUES IN HUMAN-MILK IN THE RIBEIRAO-PRETO REGION, STATE OF SAO-PAULO, BRAZIL

Thirty-seven samples of human milk (colostrum) from donors living in the Ribeirao Preto region were analyzed to determine the levels of organochlorine pesticide residues. Donors were classified into two groups, i.e., occupationally exposed and non-exposed to pesticides. Other factors such as age, previous lactations, race, smoking habit, occupation, family income and educational level were also considered. Analysis was performed by preliminary lipid extraction followed by fractional partition on a column and finally by gas chromatography with an electron capture detector. Lindane was found in 32% of the samples in amounts of less than 0.001 mg/kg; heptachlor was found in 65% of the samples at mean levels of 0.001 mg/kg, i.e., a level five-fold lower than that established by FAO/WHO (1970) for cow's milk. Aldrin and endrin were not detected in any of the samples. Dieldrin was detected in only one sample at a level of 0.038 mg/kg, which is considered high. DDT and DDE amounts are reported as total DDT and at least one of these compounds was present in every sample. Amounts detected in donors occupationally exposed to pesticides ranged from 0.008 to 0.455 mg/kg (mean, 0.149 mg/kg), i.e., three times the limit established by FAO/WHO (1970), while values for donors who had not been exposed ranged from 0.002 to 0.072 mg/kg (mean, 0.025 mg/kg), i.e., half the limit. Considering the level of acceptable daily intake proposed by FAO/WHO (1973), lactents ingested 1% of the acceptable intake of lindane (all donors), 30% of the acceptable intake of heptachlor (all donors), 60% of the acceptable intake of DDT (non-exposed donors), and 3.7 times the acceptable intake of DDT (exposed donors). Comparing the present results with those obtained 10 years ago, the total DDT level in human milk is decreasing in this part of the country. The mean amount of organochlorine residues in non-exposed women's milk was one of the lowest levels among those recorded in the literature. DDT levels of occupationally exposed women's milk were comparable with those reported for developed countries and lower than those detected in Latin American countries. When the results of this survey are considered in relation to the advantages of breast-feeding, the risk-benefit balance is still favorable to breast-feeding. However, given the lack of long-term epidemiological studies, undesirable or harmful long-lasting effects cannot be excluded.

THERMAL REGIME AND STABILITY OF JURUMIRIM RESERVOIR (PARANAPANEMA RIVER, SAO-PAULO, BRAZIL)

Thermal regime and stability in Jurumirim Reservoir (São Paulo, Brazil) were studied for a year. Isothermy and thermal stratification were observed from June to September and from October to March, respectively. The annual heat budget was 14.0 Kcal . cm-2 and average heat gain per day was 67.2 cal . cm-2 . day-1. Maximum stability and wind work reached 324.2 and 3,037.5 g . cm . cm-2, respectively. According to thermal structure and heat content, Jurumirim Reservoir was classified as a warm tropical monomictic lake.