Population differentiation and speciation in the genus Characidium (Characiformes: Crenuchidae): effects of reproductive and chromosomal barriers

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

The role of chromosome variation in the speciation of the red brocket deer complex: the study of reproductive isolation in females

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

Mechanisms of SnO2 Nanoparticles Formation and Growth in Acid Ethanol Solution Derived from SAXS and Combined Raman-XAS Time-Resolved Studies

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Lignin chemistry and topochemistry during kraft delignification of Eucalyptus globulus genotypes with contrasting pulpwood characteristics

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

Effect of hemolysis on canine, bovine and earn e serum chemistry

Hemolysis is the main cause of biochemical analysis rejection's in veterinary laboratories, however the relative error caused by hemoglobin on serum biochemical profile has not been properly established on several species. In order to establish criteria for aproval and rejection of hemolyzed samples for serum biochemical tests, the hypothesis that hemolysis causes biochemical changes in canine, cattle and horses and that laboratorial error depends on species and hemolysis degree was tested. Thus, non-hemolyzed serum was contaminated with crescent hemoglobin levels and using commercial routine reagents, the serum concentrations of uric acid, albumin, cholesterol, triglycerides and urea, besides the activity of ALT, AST, CK and GUT were quantified in triplicate samples. The relative error was calculated by the comparison between hemolyzed and non-hemolyzed samples. Hemolys is did not cause significant error on the albumin determination in all three species, AST in canine and cattle, ALT in horses, UK and cholesterol in canine. There was a linear increase on uric acid levels in horses and cattle, triglycerides in all three species. A linear increase in serum urea in all species serum, UK and cholesterol in cattle and cholesterol in horses was observed. Serum AST activity on equine serum and ALT in cattle decreased linearly due to hemolysis. It was concluded that hemolysis promotes changes in canine, equine and bovine serum chemistry profile, however the laboratorial error not necessarily compromises the diagnosis in all cases, because the changes depends on species and degree of in vitro hemolysis.

Using 3D Animations in Teaching Chemistry

This paper discuss possibilities of use of 3D animation as a tool for teaching Chemistry support. The research proposes to investigate the conception process and development of educational animations to use in a Blended Learning environment in undergraduate chemistry. Associated with general chemistry teachers, were raised the demands and difficulties on the content transmission, and the most relevant topics, about "Atomic Theory" with propose to create appropriate animations to meeting needs of themes. Thinking about offering more dynamic materials, we elaborate animations in a format of "micro-documentary", with a length between 4 and 7 minutes. We use the narration aloud to the subject-matter understanding, leaving the external text as a complement of the animation. The conclusions are positives, students accepted well the format and they proved are able to remember, organize and systematize several information presented in animations. These skills don't ensure knowledge acquisition, but may be considered prerequisites to learning occur.

Evaluation and degradation chemistry of orbifloxacin using LC-MS

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

Chemistry and pharmacology of some plants mentioned in the letter of Pero Vaz de Caminha

Brazil has a long tradition in the study of medicinal plants. When the Portuguese arrived to the new colony, Pero Vaz de Caminha, the scriber of the fleet, left the first impressions of the local and the inhabitants. He clearly mentions how the Indians use natural dye as tincture to paint their bodies. This article reviews the phytochemical and pharmacological characteristics of these colorants and other medicinal plants recently identified mentioned in this letter.

Speciation of butyltin derivatives in surface sediments of three southern Brazilian harbors

For the first time, organotin compounds were determined in surface sediment samples collected from Sao Francisco do Sul, Itajai-Navegantes and Imbituba Harbors, located in Santa Catarina State, Brazil. Butyltins (BTs) were determined by gas chromatography with a pulsed flame photometric detector (GC-PFPD) after being modified using the Grignard derivatization method. The concentrations of BTs derivatives ranged from n.d. to 1136.6 ng (Sn) g(-1) of dry weight (dw) sediment for tributyltin (TOT), n.d. to 394.4 ng (Sn)g(-1) dw for dibutyltin (DOT) and n.d. to 312.2 ng (Sn)g(-1) dw for monobutyltin (MBT). The highest concentration of total BTs was found at the Itajai-Acu River dockyard, indicating intense inputs of antifouling paints to the environment. The relative difference in the BTs levels is a particular characteristic of sediments from harbors and may be related to the shipyards and the boat traffic which still use TBT-based antifouling paints.

Theoretical chemistry: current applications to photochemistry and thermochemistry

A historical perspective is given contrasting challenges and advances in theoretical chemistry at the time the first issue of Theoretical Chemistry Accounts appeared in 1962 and the progress achieved since then as expressed in current state-of-the-art applications in photochemistry and thermochemistry.

Evaluation of comprehensive two-dimensional gas chromatography coupled to rapid scanning quadrupole mass spectrometry for quantitative analysis

Comprehensive two-dimensional gas chromatography (GC x GC) is a powerful technique that provides excellent separation and identification of analytes in highly complex samples with considerable increase in GC peak capacities. However, since second dimension analyses are very fast, detectors with a rapid acquisition rate are required. Over the last years, quite a number of studies have discussed the potential and limitations of the combination GC x GC with a variety of quadrupole mass spectrometers. The present research focuses on the evaluation of qMS effectiveness at a 10,000-amu/s scan speed and 20-Hz scan frequency for the identification (full scan mode acquisition-TIC) and quantification (extracted ion chromatogram) of target pesticide residues in tomato samples. The following MS parameters have been evaluated: number of data points per peak, mass spectrum quality, peak skewing, and sensitivity. The validated proposed GC x GC/qMS method presented satisfactory results in terms of repeatability (coefficient of variation lower than 15%), accuracy (84-117%), and linearity (ranging from 25 to 500 ng/g), while significant enhancement in sensitivity was observed (a factor of around 10) under scan conditions. (C) 2012 Elsevier B.V. All rights reserved.