Physical and chemical characteristics of the sediment in the estuarine region of Cananeia (SP), Brazil

Physical and chemical characteristics of sediment were analyzed at eight sampling areas in the estuarine region of Cananeia (SP), Brazil. The samples were collected in 1995 during four periods; summer, autumn, winter and spring. Total nitrogen and phosphorus concentrations, redox potential, water and organic matter percentage, sand and silt percentage and grain size were determined in six different layers of 20 cm deep columns of sediment. In general, the nutrient concentration and the percentage of organic matter decreased with depth and greater variations were observed in the first centimeter of the samples. Differences in nutrient concentration and organic matter were also observed during the study period. The highest concentrations were recorded during the rainy season (February) as a consequence of an accumulation of organic matter brought into the system by rivers and adjacent flooded areas. In general, the sediments had oxidized characteristics until the 5 or 10 cm depth in areas near the rich coastal vegetation. However, in areas open to the ocean, the entire sediment columns were almost completely oxidized.

Influence of physical and chemical factors during foraging and culture of the symbiont fungus in Atta sexdens rubropilosa (Hymenoptera : Formicidae)

The aim of this paper is to investigate the influence of physical and chemical factors on transport and use of substrate for Atta sexdens rubropilosa workers. Three types of rectangular fragments were used to study the physical influence factors: filter paper with paraffin, filter paper without paraffin and polyester film. To study the chemical factors, some fragments were impregnated with organic extract of orange albedo, others were soaked with soybean oil and for the remaining ones nothing was applied. The following parameters were evaluated: (i) attractiveness of substrate for transport and number of loading workers per treatment; (ii) foraged material incorporation; (iii) rejection by numbers of fragments deposited in the garbage or beside the fungus garden. All the polyester film fragments carried out to the fungus garden were subsequently rejected. We verified that chemical factors of the substrate were more quickly detected by the workers, whereas physical factors were used as a criterion in the decision-making to reject or accept the substrate collected.

Vegetation and environmental heterogeneity relationships in a Neotropical swamp forest in southeastern Brazil (Itirapina, SP)

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Leaf gas exchange and fruit yield in sweet orange trees as affected by citrus variegated chlorosis and environmental conditions

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

Spatial variability of the physical and mineralogical properties of the soil from the areas with variation in landscape shapes

Este trabalho teve como objetivo avaliar a influência das formas do relevo na variabilidade espacial de atributos físicos e suas relações com a mineralogia da argila de um Latossolo Vermelho eutroférrico, utilizando a técnica da geoestatística. Os solos foram amostrados nos pontos de cruzamento de uma malha, com intervalos regulares de 10 m, nas profundidades de 0,0-0,2 m, 0,2-0,4 m e 0,4-0,6 m para os atributos físicos e 0,6-0,8 m para os atributos mineralógicos. Os valores médios para a densidade do solo e resistência do solo à penetração são maiores no compartimento I onde a relação Ct/Ct+Gb é relativamente maior, indicando a presença de maior teor de caulinita. No compartimento II a condutividade hidráulica e a macroporsidade são maiores, influenciados provavelmente pelo predomínio da gibbsita. Portanto, conclui-se que a identificação das pedoformas é muito eficiente para compreender a variabilidade espacial de propriedades do solo. Sendo que, as variações na forma da paisagem promovem variabilidade espacial diferenciada das propriedades físicas e mineralógicas do solo.

Yellow passion fruit seed oil (Passiflora edulis f. flavicarpa): physical and chemical characteristics

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

Physical and mechanical properties of ceramics from clays of the west of S. Paulo State, Brazil

Argilas de interesse da indústria de cerâmica estrutural foram caracterizadas. Algumas propriedades físicas de diversas massas cerâmicas, preparadas a partir de material coletado em depósitos artificiais, também foram analisadas. Todas as massas investigadas exibem alta concentração de componentes finos (< 2 mim) e considerável grau de plasticidade, o que é compatível com a presença de elevado teor de argilominerais. Corpos de prova cerâmicos foram preparados por prensagem a seco e queimados em temperaturas ao redor de 855 °C. Os parâmetros resistência mecânica à flexão, retração linear, absorção de água, cor aparente e perda de peso foram medidos. Como resultado, as aplicações industriais destas matérias primas foram analisadas e revistas, bem como novas aplicações foram propostas.

Reproductive physiology, and physical and sexual development of female offspring born to diabetic dams

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

Interactions between genetic predisposition and environmental toxicants for development of lung cancer

Significant interindividual variations in health outcome may be caused by the inheritance of variant polymorphic genes, such as CYP2D6 and CYP2E1 for activation, and GSTM1 and GSTT1 for detoxification of chemicals. However. mechanistic studies linking the inheritance of predisposing genes with genotoxic effects towards cancer have yet to be systematically conducted. We have studied 54 lung cancer patients and 50 matched normal controls, who have been cigarette smokers, to elucidate the role of polymorphic genes in cancer. Our data indicates that the inheritance of unfavorable CYP2D6, CYP2E1, and GSTT1 genes is strongly correlated with the smoking-related lung cancer. For heavy cigarette smokers (> 30 pack-years), the smoking habit is the strongest predictor of lung cancer risk irrespective of the inheritance of unfavorable metabolizing genes. For moderate to light smokers (< 30 pack-years), the genetic predisposition plays on important role For the risk (odds ratio = 3.46; 95% CL = 0.46-40.2). Using a subgroup of the study population, we observed that cigarette smokers having the defective GST genes have significantly more chromosome aberrations as determined by the fluorescence-in-situ-hybridization (FISH) technique than smokers with the normal GST genes (P < 0.001). In conclusion, our study provides data to indicate that individuals who have inherited unfavorable metabolizing genes have increased body burden of toxicants to cause increased genetic damage and to have increased risk for cancer. Studies like ours can be used to understand the basis for interindividual variations in cancer outcome, to identify high risk individuals and to assess health risk. (C) 1997 Wiley Liss, Inc.

Effects of sire breed-grazing system and environmental parameters on the behaviour of beef calves just after birth

Effects of sire breed-grazing system and environmental factors on the first activities of high grade Nellore and crossbred Canchim x Nellore, Angus x Nellore, and Simmental x Nellore calves raised in intensive production systems and high grade Nellore calves raised in an extensive production system, after birth, were studied. During 2 years, 185 calves were observed from birth until the end of first suckling, and the following variables were estimated: duration of maternal attention (cow to calf) during the first 15 min after calving, latency to first attempt to stand up, latency to stand up, latency to first suckling, duration of first suckling and the interval from standing to suckling. Data were analyzed by least squares methods, with models that included fixed effects of year and time of the year of birth (March-April (early autumn) and May-June (late autumn)), sire breed-grazing system (Sy), sex of calf (Se), category of cow (primiparous and pluriparous), time of birth, Sy x Se, year x Sy and year x time of the year interactions and the covariates weight of calf, rainfall, air temperature and relative humidity in the day of birth. Calves born from 6:00 to 8:00 h presented the longest latencies to first stand up (40.3 +/- 5.1 min) and the shortest occur from 14:00 to 16:00 h (15.8 +/- 2.7 min) (P < 0.01). Primiparous cows provided longer attention toward the calf in the first 15 min after birth than pluriparous cows (13.0 +/- 0.7 min versus 11.1 +/- 0.5 min; P < 0.05). This attention was also shorter in earlier autumn (11.0 +/- 0.5 min) and longer in late autumn (13.1 +/- 0.8 min) (P < 0.05). Relative to sire breed-grazing system, Nellore calves raised intensively did take longer to stand and to suckle after birth as compared to crossbred calves also raised intensively (P < 0.01). However, grazing system did not affect (P > 0.05) any behaviour variable studied. As regard to sex differences, female calves did take less (P < 0.01) time to suckle after standing than male calves. Results showed that even purebred or crossbred Bos indicus calves in subtropical environmental need extra care when born on rainy days, especially during the first hours of the day. (C) 2006 Elsevier B.V. All rights reserved.

Influence of management and environmental factors on mating success of Africanized queen honey bees

Environmental factors and management techniques were evaluated in São Paulo, Brazil, for enhanced production of Africanized queen honey bees. Queens were reared by the Doolittle method; 12 breeder, 6 cell-builder, and 36 3-frame nucleus colonies were used. Nine groups of four virgin Africanized queen honey bees were subjected to the following treatments: queens were either 1-2, 3-4 or 5-6 days old and were released into mating nuclei containing either capped brood, uncapped brood or no brood. This was repeated sixteen times between August 1990 and August 1992. Seven repetitions occurred during nectar flow periods and nine repetitions occurred during nectar-dearth periods. Overall, 59% of 576 queens were successfully introduced and mated. The best results (93% success) were obtained during nectar flows, with 3- to 4-day-old queens released into nuclei containing capped brood. During nectar dearths the best mating success came from queens introduced into broodless nuclei (63%), the age of the queen did not influence mating success. Mating success decreased when wind velocity increased; this was the only significant meteorological effect found.

Analysis of pesticides in food and environmental samples by enzyme-linked immunosorbent assays

Enzyme-linked immunosorbent assays (ELISAs) are the most extensively studied types of immunoassay and their application in pesticide residue monitoring is an area with enormous potential for growth. In comparison with classical analytical methods, ELISA methods offer the possibility of highly sensitive, relatively rapid, and cost-effective measurements. This review introduces the general ELISA formats used, focusing on their use in pesticide analysis. Identifying and studying the effects of interferences in immunoassays is an active area of research and we discuss the matrix effects observed in several studies involving e.g. food, crop and environmental samples. The procedures to eliminate the matrix interferences are briefly discussed. (C) 1998 Elsevier B.V. B.V.

Genetic and environmental effects over milk production of buffalo cows in Brazil

The objective of this paper was to evaluate the relevance of environmental and genetics effects on milk production of buffalo cows in Brazil. The data were based on the Buffalo Genetic Improvement Program - PROMEBUL, using information of 1,911 cows (107 Jafarabadi, 101 Mediterranean, 1,056 Mu/Tab and 647 crossbred females) with parturition between 1982 and 2003. The mathematic model for evaluating milk production included the fixed effects of herd, parturition year (1982 to 2003) and month (January to December), calf's sex (male or female), genetic group (Jafarabadi, Mediterranean, Murrah, and crossbreed), number of milking (one or two), lactation order (1 to 12) and duration of lactation (as a linear effect). The mean milk production in herds was 1,590.36 +/- 609.25 kg. All sources of variation were significant (P<0.05) for the studied characteristics, except calf's sex. The mean milk production per genetic group was 1,651.4; 1,592.2; 1,578.3 and 1,135.5 kg, for Murrah, Mediterranean, Crossbred and Jafarabadi, respectively. The duration of lactation was the most important source of variation over milk production, followed by the year of parturition, herd, parturition order, genetic group and month of parturition.

Genetic and environmental effects on parturition and lactation intervals in water buffaloes from Brazil

Genetic and environmental effects on parturition interval (PI) and duration of lactation (DL) were evaluated in 107 Jafarabadi, 98 Mediterranean, 1027 Murrah and 624 crossbred buffalo females (n=1856), based on data from the Buffalo Genetic Improvement Program-PROMEBUL from 1980 to 2003. The statistical model included effects of herd, parturition year and month, calf's sex, parturition order and genetic group, composing 11, 34, 12, 2, 12 and 4 classes, respectively. A significant effect over PI was observed (P<0.01) in all classes, excepting sex. Mean parturition intervals per genetic group presented significant differences through SNK test (P<0.05), with mean values of 451.29; 429.47; 406.97 and 389.78 days in Mediterranean, crossbred, Murrah and Jafarabadi, respectively. Mean DL values were 276.68; 270.33; 258.03 and 235.59 days for Mediterranean, Murrah, crossbred and Jafarabadi groups, respectively. No significant differences in DL were observed in relation to genetic groups. However, herd and parturition order, year and month significantly influenced DL (P<0.01). The herd was the main source of variation over DL, followed by parturition year and month. A regression based on parturition month in relation to PI and DL showed that females giving birth in the last months of the year presented higher PI and DL.

Diagnosis and environmental planning for Paranagud - PR - Brazil

The main goal of this study was to identify and analyse environmental problems related to human occupation at the south part of the city of Paranagua PR, Brazil, aiming the diagnosis and conceptual evaluation of landscape use. For landscape use assessments and degradation diagnosis purposes, the environment was classified considering mainly geological and geomorphologic characteristics, such as declivity and sediment origin. The identification of potential environmental impacts was made by aerial photographs, Landsat-TM images, photographic records, surface sediment samples, water-column samples, and mainly observation visits to each classified unit. Surface sediment samples were taken with a Petit-Ponar sampler, in 13 station located in Paranagua Bay. In order to characterize the contamination level on sediments, the concentration of the following elements were analysed: arsenic (As), copper (Cu), cadmium (Cd), nickel (Ni), lead (Ph) e zinc (Zn). For the extraction of these elements, samples were treated with HCl 0.1N for 12 hours. This method has the advantage of determining contaminants which are weakly bind to the sediment, thus more available to the system. Analysis were performed by atomic absorption spectroscopy. According to the adopted criteria, sectors were classified as hills, mangroves, continental sediments and beach ridges urban and port industrial. Water quality and concentrations of metallic elements were determined at three sectors one control and two with the influence of urban and port/industrial activities, respectively the major upland impacts found were: deforestation due to disordered occupation, and solid waste emission through domestic and industrial sewage. The diagnosis of the actual situation was used as a basis for a management plan, once it allows the identification of impacts, and consequent environmental irregularities. Based on this considerations, suggestions for land use and management were presented, which offers a better approach for recuperation and protection of the studied ecosystem.