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São Paulo, Brazil

Vampre T.M.,Instituto Biologico | Fuccillo R.,Faculdades Oswaldo Cruz | de Andrea M.M.,Brazilian National Council for Scientific and Technological Development
Revista Brasileira de Ciencia do Solo | Year: 2010

HCB (hexachlorobenzene) is an environmentally ubiquitous organochlorine compound and is classified as one of the persistent organic pollutants (POP). It is highly toxic and has been found in the region "Baixada Santista" of the state of São Paulo (Brazil) for a number of years. To evaluate the potential of the earthworm species Eisenia andrei as bioindicator of HCB-contamination, earthworm specimens were maintained for 14 days in soil containing 14C-HCB, and their bioaccumulation was analyzed. No mortality was detected after neither 7 nor 14 days of contact with the treated soil, indicating that the dose was sub-lethal and would enable a biondication study. Soil and animal tissue samples were submitted to solvent extraction 14 days after the beginning of the study to determine radiocarbon, HCB and lipid contents in the organisms. Most of the radiocarbon from the applied 14C-HCB remained in the soil in the form of extractable residue and only small amounts were found in the animal tissues as extractable and bound residues. The gas chromatography of the extracts detected only HCB and consequently, no degradation occurred, neither in the soil, nor in animal tissues. The lipid content of the earthworm tissues was negatively correlated with HCB amounts (-0.2), indicating that HCB may have inhibited lipid formation. Finally, the bioaccumulation factor (BAF) of 6.5 indicated that HCB is actually bioaccumulated by the worms which indicates that this animal may be used as bioindicator in HCB-contamination studies. Source

De Lima I.L.,Instituto Florestal Do Estado Of Sao Paulo | Garcia R.,Faculdades Oswaldo Cruz | Longui E.L.,Instituto Florestal Do Estado Of Sao Paulo | Florsheim S.M.B.,Instituto Florestal Do Estado Of Sao Paulo
Scientia Forestalis/Forest Sciences | Year: 2011

For the better use of Tectona grandis wood it is necessary to study the relationship between the anatomy and wood quality with the factors that may affect growth conditions. Spacing is one of growth factors to be considered for production and a better quality of teak wood. The aim of the present work was to verify the influence of spacing on the cellular dimensions of the wood of a 31-year old Tectona grandis tree; and its radial variability. In this study, we used the e×perimental delineation of randomized blocks with three treatments (3 × 1.5; 3 × 2 and 3 × 2.5m) and five replications, and where 15 trees with average diameter were chosen in the region of Pederneiras/SP. From each tree a disc of 7cm thickness at DBH (diameter at breast height) was removed and from each disc samples were taken in different distances in pith-to-bark radial direction (pith, intermediate and bark). It was concluded that the fiber length, fiber wall thickness and frequency vessel were influenced by spacing of planting. A good positive relationship was found between fiber length and fiber wall thickness with radial position and a negative relation between vessel diameter and ray frequency with the radial position. Source

Bulcao R.,Federal University of Rio Grande do Sul | Garcia S.C.,Federal University of Rio Grande do Sul | Limberger R.P.,Federal University of Rio Grande do Sul | Baierle M.,Federal University of Rio Grande do Sul | And 3 more authors.
Quimica Nova | Year: 2012

In the recent years, analytical toxicologists have been facing difficulties in detecting designer drugs due to the chemical modifications on the existing structures and the speed in which they are released into the market, requiring the development and improvement of specific and appropriate analytical methods. This work is a review of the literature which summarizes the characteristics of the drugs and the analytical validated methods using conventional and unconventional matrices currently used for correct identification and quantification of the following classes of emerging drugs of abuse: derivatives of opiates, amphetamines, tryptamines, piperazines and cannabinoids. Source

Araujo Reis-Menezes A.,University of Sao Paulo | Gambale W.,University of Sao Paulo | Cintra Giudice M.,Faculdades Oswaldo Cruz
Indoor and Built Environment | Year: 2011

Libraries are very propitious environments for the growth of fungi. The great concentration of organic material available for these microorganisms, and often with the lack of adequate ventilation or climate control, would favour this situation. This study was conducted in 2003 to determine the predominant genera of fungi in public libraries by a survey of fungi contaminating the upper surface of books, with and without air conditioning in the city of São Paulo, Brazil, in the winter and summer, during the respective periods with high and low levels of airborne fungi in that city. Six libraries were chosen, located on the campus of the University of São Paulo, three of them with air conditioning and the other three with natural ventilation. In these six libraries, 31 genera of fungi were identified in total. The genera and frequency of contaminant fungi recovered differed significantly between the libraries with and without air conditioning and in the samples collected in the summer as opposed to the winter. Cladosporium was the most frequent in the libraries with and without air conditioning, and in the winter. Aspergillus was isolated more often in the summer. © The Author(s), 2011. Source

Ferreto H.F.R.,Brazilian Nuclear Energy Research Institute (IPEN) | Oliveira A.C.F.,Brazilian Nuclear Energy Research Institute (IPEN) | Gaia R.,Faculdades Oswaldo Cruz | Parra D.F.,Brazilian Nuclear Energy Research Institute (IPEN) | Lugao A.B.,Brazilian Nuclear Energy Research Institute (IPEN)
AIP Conference Proceedings | Year: 2014

The aim of this paper is to investigate structural changes of high density polyethylene (HDPE) modified by ionizing radiation (gamma rays) in different atmospheres. The gamma radiation process for modification of commercial polymers is a widely applied technique to promote new physical-chemical and mechanical properties. Gamma irradiation originates free radicals which can induce chain scission or recombination, providing its annihilation, branching or crosslinking. This polymer was irradiated with gamma source of 60Co at doses of 5, 10, 20, 50 or 100 kGy at a dose rate of 5 kGy/h. The changes in molecular structure of HDPE, after gamma irradiations were evaluated using thermogravimetric analysis (TGA) and tensile machine and oscillatory rheology. The results showed the variations of the properties depending on the dose at each atmosphere. © 2014 American Institute of Physics. Source

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