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

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A simple and rapid method was developed for the determination of amfepramone hydrochloride, fenprorex, and diazepam in capsules using high performance liquid chromatography (HPLC) with UV detection. This procedure provided conditions for the separation of the active ingredient from the complex matrices of the dosage forms by extraction in methanol. Isocratic reversed phase chromatography was performed using acetonitrile, methanol, and aqueous 0,1% ammonium carbonate (50:10:40) as a mobile phase, LiChrospher 100 RP 18 column (125 x 5 mm id, 5 mu m), a column temperature of 25 +/- 1 degrees C and detection at 230 nm.The calibration curves were linear over a wide concentration range (20-2000 mu g.mL(-1) to amfepramone hydrochloride, 8-800 mu g.mL(-1) to fenproporex, and 4-200 mu g.mL(-1) to diazepam) and good analytical recovery (87.1 to 107.8%) was obtained. The method is accurate and precise, as well as having advantages such as simplicity and short duration of analysis. Twenty samples of pharmaceutical preparations labelled as natural products were analysed. Anorectics and diazepam, were detected in 40% of the samples.

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Este artigo busca explorar a condição do narrador performer no conto “Sarapalha”, de Guimarães Rosa. A partir da construção das personagens no universo da ficção, parte-se para articulação entre o campo da performance e da literatura, explorando os signos que desestabilizam as categorias de espaço, tempo e ação. A abordagem priva pela aproximação das categorias narrativas com as categorias performáticas do texto, apontando os índices simbólicos e as estratégias de construção e elaboração presentes no universo rosiano. Para tanto, privilegiou-se o cruzamento entre o narrar e o performatizar como ações da escritura, bem como os níveis de materialidade e fisicalidade contidos no conto

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

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Specimens of the zipper sand skate Psammobatis extenta were collected in the region of Ubatuba off the northern coast of the State of São Paulo, Brazil, monthly for once year (January - December 2000), at 25- to 40-m isobaths. A total of 123 individuals were caught. The total length (TL) of females averaged 224.6 mm, and of males 217 mm. The overall sex ratio was 1:1. Analysis of the length-weight relationship indicated the existence of positive allometry in females, and isometry in males. The length at onset of sexual maturity was determined for both sexes; females reached sexual maturity at smaller sizes than males (TL50 = 230.7 and TL50 = 237.7 mm respectively). Females showed functional parity of both ovaries and uteri. Females that were pregnant or were carrying vitellogenic oocytes were observed during nine of 12 months of the survey, indicating a continuous reproductive cycle. Psammobatis extenta was most abundant from January to April, and again from June to October. Most individuals were collected at the 40-m isobath. Both adults and neonates were collected in the study area. However, adolescent skates were scarce, which either indicates differential occupation of the area, or suggests that the shallow waters of the continental shelf are used as breeding grounds.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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Cellulose can be obtained from innumerable sources such as cotton, trees, sugar cane bagasse, wood, bacteria, and others. The bacterial cellulose (BC) produced by the Gram-negative acetic-acid bacterium Acetobacter xylinum has several unique properties. This BC is produced as highly hydrated membranes free of lignin and hemicelluloses and has a higher molecular weight and higher crystallinity. Here, the thermal behavior of BC, was compared with those of microcrystalline (MMC) and vegetal cellulose (VC). The kinetic parameters for the thermal decomposition step of the celluloses were determined by the Capela-Ribeiro non-linear isoconversional method. From data for the TG curves in nitrogen atmosphere and at heating rates of 5, 10, and 20 A degrees C/min, the E(alpha) and B(alpha) terms could be determined and consequently the pre-exponential factor A(alpha) as well as the kinetic model g(alpha). The pyrolysis of celluloses followed kinetic model g(alpha) = [-ln(1 - alpha)](1.63) on average, characteristic for Avrami-Erofeev with only small differences in activation energy. The fractional value of n may be related to diffusion-controlled growth, or may arise from the distributions of sizes or shapes of the reactant particles.

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Objetivou-se avaliar as características morfológica e funcional do sêmen bovino congelado comparando-se a eficácia de dois diferentes diluidores. O ejaculado de quatro touros foi dividido em duas partes iguais, uma submetida ao diluidor Tris e gema de ovo (A) e outra ao diluidor à base de lecitina de soja (Andromed®) (B). No experimento I, cinco palhetas dos diluidores A e B de cada touro foram descongeladas e avaliadas quanto à motilidade, vigor, concentração, morfologia espermática e teste de termor-resistência lento. Foram feitas, ainda, avaliação da integridade de membranas, por meio da associação das sondas iodeto de propídio, isotiocionato de fluoresceína - Pisum sativum e carbocianina catiônica lipofílica, e avaliação funcional da membrana plasmática com teste hiposmótico. A avaliação da integridade da cromatina foi realizada pelo método de coloração com laranja de acridina. No experimento II, o sêmen com os diferentes diluidores foi utilizado na fecundação in vitro, sendo observadas taxas de clivagem e desenvolvimento embrionário in vitro. em relação aos resultados obtidos, apenas a porcentagem de espermatozoides no sêmen congelado foi discretamente maior com o diluidor A, concluindo-se que o diluidor composto por lecitina de soja pode substituir o composto por Tris e gema de ovo, respeitando-se as variações individuais de cada touro utilizado no presente experimento.

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Using a freeze-etch technique the cytoplasmic and plasma membrane ultrastructure of Paracoccidiodies brasiliensis yeast-phase cells was studied. The multinucleate yeast-phase cells which grow by simultaneous multiple budding, like those of Mucor sp. contain several nuclei, mitochondria, well-developed ER, small vacuoles and lipid droplets. Complex structures with no apparent connexion to the plasma membrane of P. brasiliensis usually lack inveginations, but invaginations which do occur are always rod-shaped which indicates P. brasiliensis to be of either ascomycetous or basidiomycetous origin.

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This work describes an analytical procedure for vanadium determination in human hair slurries by electrothermal AAS using longitudinal heating (LHGA) and transversal heating (THGA) graphite furnace atomizers. The samples were powdered using cryogenic grinding and the hair slurries containing 0.2% (m/v) were prepared in three different media for determination of vanadium: 0.14 mol L-1 HNO3, 0.1% (v/v) Triton X-100 and 0.1% (v/v) water soluble tertiary amines (CFA-C, pH 8). The limits of detection (LOD), limits of quantification (LOQ), and characteristic masses obtained were 0.28, 0.95 mu g L-1 and 35 pg (LHGA) and 0.34, 1.13 mu g L-1 and 78 pg (THGA), respectively. The accuracy of the analytical results obtained by the proposed procedure in both equipments was confirmed by a paired t-test at the 95% confidence level and compared with a conventional procedure based on acid digestion. (c) 2006 Elsevier B.V. All rights reserved.

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Films containing different volumes of latex of natural rubber (NR) in a fixed mass of poly (vinylidene fluoride) (PVDF) powder were fabricated by compressing under annealing a mixture of both materials without using any solvent. This is an important issue keeping in mind that these films have to be used in the future as biomaterials in different applications once the solvents that are used to dissolve the PVDF become toxic to human. The films with different percentage of latex in PVDF were characterized using microRaman scattering and Fourier transform infrared absorption (FTIR) spectroscopies, thermomechanical techniques using thermogravimetry (TG), differential scanning calorimetry (DSC), dynamical-mechanical analysis (DMA) and scanning electron microscopy (SEM). The results showed that the latex of NR and PVDF do not interact chemically, leading to the formation of a polymeric blend with high thermal stability and mechanical properties suitable for applications involving bone (prostheses, for instance). Besides, the results recorded using the micro-Raman technique revealed that for a fixed amount of PVDF the higher the amount of latex in the blend, the better the miscibility between both materials. Copyright (c) 2005 John Wiley & Sons, Ltd.

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This work presents the study of substrate surface effects on rhodamine B-containing silica films obtained from TEOS (tetraethylorthosilicate) acid hydrolysis. Soda-lime glass substrates were treated with basic solution under different reaction times and temperatures. Rhodamine B-containing silica films were deposited on pre-treated substrates by the spin-coating method. The substrate surface directly affects film morphology and homogeneity. The films are formed by packed silica spheres which protect the dye against acid-base attack. Luminescence spectra present shifts on the dye emission maximum as expected for different pH values on the substrate surface depending on the alkaline treatment. (c) 2006 Elsevier B.V. All rights reserved.

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The objectives of the present study were to evaluate factors associated with estrous synchronization responses and pregnancy per insemination (P/AI) in Bos indicus beef cows submitted to progesterone-based fixed-time artificial insemination (FTAI) protocols. A total of 2388 cows (1869 Nellore and 519 crossbred Nellore x Angus) from 10 commercial farms were evaluated to determine the relationships among breed, body condition score (BCS) on the first day of the FTAI protocol, the occurrence of estrus between progesterone device removal and FTAI and diameter of largest ovarian follicle (LF) at FTAI on estrous synchronization responses and P/AI. Cows (n=412 primiparous; 1976 multiparous) received an intravaginal device containing progesterone or an ear implant containing norgestomet (a progestin), and an injection of estradiol at the beginning of the estrous synchronization protocol. Body condition was scored using a 1-5 scale on the first day of the FTAI protocol and at 30-60 days postpartum. Females received 300IU of equine chorionic gonadotropin (eCG) and PGF(2 alpha) on the day the progesterone device/implant was removed and were inseminated 48-60h later. At insemination, cows (n=2388) were submitted to an ultrasonographic exam to determine the diameter of the LF. Follicles were classified into four categories based on mean and standard deviation (SD) of the LF (LF1 = two SD below the mean; LF2 = mean minus one SD; LF3 = mean plus one SD; LF4 = two SD above the mean). Ovulation rate was determined in a subset of cows (n=813) by three consecutive ultrasonographic exams: (1) at time of progesterone device/implant removal, (2) at time of FTAI and (3) 48 h after FTAI. Ovulation was defined as the disappearance of a large follicle (>= 8.0 mm) that was previously recorded. Estrus was determined in a subset of the cows (n = 445) by the activation of a detection of estrous patch placed on the tail head on the day of progesterone device/implant removal. Pregnancy was diagnosed 30 days after FTAI. Pregnancy was influenced (P = 0.001) by follicle diameter [LF1 = 27.5% (81/295), LF2 = 46.6% (328/705), LF3 = 57.9% (647/1118), LF4 = 63.3% (171/270)] and the occurrence of estrus [estrus = 67.7% (174/257) and no estrus = 36.2% (68/188)]. Follicle diameter at FTAI influenced ovulation rate [LF1 = 42.5% (34/80), LF2 = 73.9% (161/218), LF3 = 95.8% (407/425), LF4 = 97.8% (88/90)], the occurrence of estrus [LF1 = 54.8% (51/93), LF2 = 33.6% (43/128), LF3 = 68.9% (126/183), LF4 = 90.2% (37/41)] and P/AI among cows that had ovulations [LF1 =32.4% (11/34), LF2 = 50.3% (81/161), LF3 = 60.0% (244/407), LF4 = 68.2% (60/88)]. Improving estrous responses between progesterone device withdrawal and FTAI and increasing the diameter of the LF at FTAI may be important aspects to achieve improved estrous synchronization responses and P/AI following progesterone/progestin and estradiol based FTAI protocols in suckled Bos indicus cows. (C) 2010 Elsevier B.V. All rights reserved.