Bioaccumulation of tributyltin by blue crabs

This study evaluated the bioaccumulation of tributyltin (TBT) by the blue crab (Callinectes sapidus). Animals were fed with contaminated food containing 30 µg g-1 of TBT expressed as Sn. The analytes were determined in the gills, hepatopancreas and muscle. Acid digestion was used in the total Sn determination, and a solid-phase extraction technique was used for the selective determination of TBT. Limits of detection of 44.6 and 4.46 ng g-1 were found for HG-ICP OES (hydride generation-inductively coupled plasma optical emission spectroscopy) and ICP-MS (ICP-mass spectrometry), respectively. The results for non-contaminated animals were below 50 ng g-1, while the animals subjected to the contaminated food showed higher tissue concentrations of Sn (until 6229 ng g-1) and TBT (until 3357 ng g-1) related to the number of exposure days. According to the results, Sn is bioaccumulated by the blue crab in higher concentrations in the hepatopancreas. For most of these animals, the results suggest that Sn is bioaccumulated as TBT.

Sintese e aplicação de filmes biocomponentes nanoestruturados de 'TI'/'TI''O IND.2'/'W''O IND.3' por template e 'SI'/'TI''O IND.2'/'PT' por heterojunção em conversão de energia solar e remediação ambiental

Pós-graduação em Química - IQ

Action of Brazilian propolis on hematological and serum biochemical parameters of Blue-fronted Amazons (Amazona aestiva, Linnaeus, 1758) in captivity

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Selective photoinactivation of Candida albicans in the non-vertebrate host infection model Galleria mellonella

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Silica-based Nano-coating on Zirconia Surfaces Using Reactive Magnetron Sputtering: Effect on Chemical Adhesion of Resin Cements

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

A New and Simple Visual Technique Based on Indigo Dye for Determination of Ozone in Ambient Air

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Are Reactive Rock Phosphate and Superphosphate Mixtures Suitable for No-Till Soybean?

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

Comparative Analysis of Azo Dye Biodegradation by Aspergillus oryzae and Phanerochaete chrysosporium

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

The triple near-Earth asteroid (153591) 2001 SN263: an ultra-blue, primitive target for the Aster space mission

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Reduced levels of intracellular reactive oxygen species and apoptotic status are not correlated with increases in cryotolerance of bovine embryos produced in vitro in the presence of antioxidants

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

In Vitro Assessment of Mutagenic And Genotoxic Effects of Coumarin Derivatives 6,7-Dihydroxycoumarin and 4-Methylesculetin

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

INFLUENCE OF NOZZLE TYPE AND SPRAY RATES ON CORN AND WEED PLANTS DROP DEPOSITIONS

The objective of this study was to evaluate different nozzles and spray rates on drop deposition in corn (Zea mays), Euphorbia heterophylla and Brachiaria plantaginea, both weeds located at and between crop rows. The experimental design established was complete random blocks with treatments arranged at 2 x 2 factorial scheme (2 nozzles types: DG11002VS flat flan and medium droplets, TXVK08 cone and very fine droplets; and 2 rates: 100 and 200 L ha(-1)) with four replications. The spray applications occurred at 13 days after corn germination (3-5 expanded leaves), when E. heterophylla and B. plantaginea plants had 2-4 and 2-3 leaves, respectively. Solution of Brilliant Blue (FD&C-1) dye at 3,000 ppm was used as spray tracer. It was concluded that the greatest average deposits in corn plants was provided by TXVK08, independently of the spray rates used. The most uniform deposits occurred when the spray rates of 200 L ha(-1) was used. Spray deposits were most uniform in B. plantaginea compared to E. heterophylla when both weds were located at crop row, independently of nozzle or spray rates. However, the DG 11002VS spray nozzle provided the most uniform drop deposition on B. plantaginea located between the rows, while the most efficient deposition over E. heterophylla located between rows was TXVK08.

Estudo fotodinâmico da clorofila a, azul de metileno e rosa bengala como agente inseticida contra Aedes aegypti

Photodynamic therapy, term introduced by von Tapeiner in 1900, can be defined as the administration of a non toxic drug, i.e., a dye, known as photosensitizer (FS), which subsequently will be illuminated with light of specific wavelength. PDT is based on the interaction among FS, oxygen and light, which through photochemical reactions cause cell death. The FS molecules must have a high probability to form the singlet state after the excitation, which can induce chemical changes in the neighborhood in two ways, called reactions type I and type II. The type II reaction is based on the exchange of energy to molecular oxygen, exciting it to its state of higher energy (singlet), which is highly reactive. The proposed mechanisms for cell death are linked to damage to the DNA, mitochondria and to the cytoplasmic membrane. Several pre‐clinical and clinical trials have been carried out and the PDT is already used in many countries for treatment mainly against certain types of cancer. The therapy also has been gaining strength in antimicrobial control, since the microorganisms have appeared increasingly resistant to current antibiotics. Another attempt to use the PDT is for the inactivation of macro‐organisms, such as micro‐crustaceans and mosquitoes. To this end I tested whether the photosensitizers methylene blue, rose Bengal and the chlorophyll a has insecticidal activity against the yellow fever and dengue vector mosquito, Aedes aegypti. Since these diseases have no effective treatments, its control is linked to the vector control, which has shown resistance to chemical pesticides used. Based on this, this work shows its importance, because it is a new type of mosquito control since all the photosensitizers used are low cost, do not generate toxic products at the concentrations used and showed good results in mortality. The best photosensitizer was rose Bengal... (Complete abstract click electronic access below)

Avaliação da viabilidade e desenvolvimento in vitro de oócitos de gatas domésticas após vitrificação em meio suplementado com vitamina E

Pós-graduação em Medicina Veterinária - FCAV

Removal of dyes by lignocellulose adsorbents originating from biodiesel production

In this study, use was made of tucumã cake, in natura (TCN) and thermally treated (TCT), as potential alternative adsorbents for the adsorption of cationic and anionic dyes. The effects of the parameters: contact time, adsorbent: adsorbate mass ratio, and initial concentration of dye were analyzed. The adsorption isotherms were established from optimized adsorption parameters. The best conditions for adsorption were: equilibrium time of 7 h, concentration of 25 mg L 1 and ratio of 1:200 for the methylene blue dye; and pH 6.5, concentration of 25 mg L 1 and ratio of 1:200 for the congo red dye. The adsorption process was best represented by the Dubinin–Radushkevich and Sips isotherms. The kinetics of adsorption of the dyes were best described by the pseudo-second-order kinetic and Elovich models. TCT showed the best maximum adsorption capacity (Qm) for the methylene blue dye (63.92 mg g 1 ).