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Estudou-se o efeito do choque a frio e da cera, na conservação pós-colheita do maracujá-doce (Passiflora alata Dryander), verificando as principais alterações físicas e químicas durante o armazenamento. Os frutos, colhidos no estádio pré-climatérico, foram desinfetados com hipoclorito de sódio e em seguida, submetidos aos tratamentos: testemunha; cera Sta fresh (1:2); choque frio (-2°C por 2 horas) + cera Sta fresh (1:2); choque frio (-2°C por 2 horas). Os frutos foram avaliados a cada 6 dias quanto a perda de peso, textura, rendimento de suco, sólidos solúveis totais e acidez total titulável. Após 30 dias a 9°C e 85-90% UR, pode-se concluir que o tratamento mais adequado à conservação do maracujá-doce foi o que utilizou a cera Sta Fresh. Os tratamentos com choque a frio e com choque a frio + cera não foram eficientes para manutenção da qualidade pós-colheita do maracujá-doce.

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This review concerns the phenomenon of heterogeneous growth (Het-G) in fish. Het-G is characterized by different growth rates between conspecifics. Although genetic determination on Het-G is recognized, grouping increases the difference in size between conspecifics. This review focuses on population factors and the mechanisms underlying the socially mediated Het-G are summarized and discussed. The aim of this paper is to arrive at a general statement explaining why grouping decreases mean growth and why it suppresses growth only in some individuals. The mechanisms described are: a) food competition, b) chemical factors released by conspecifics, and c) social stress. Social stress is analyzed in terms of the effect on appetite, digestive processes and metabolism. It is proposed that the predominant mechanism promoting socially mediated growth suppression is related to the social habit of the species. The biological significance of growth heterogeneity in fish is also discussed. Growth variability is suggested as an adaptative strategy to optimize survival of the population in a restricted space.

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This paper appraises the influence of chelipeds on sexual and maturation phasis of the crab Hepatus pudibundus (Herbst, 1785), collected in Ubatuba (SP) region. The allometric constants obtained from the regression (carapace width X cheliped weight) adjusted to a power function (Y=aX(b)) were analysed. It was verified that males show larger chelipeds than females. The mean percentage of the chelipeds weight differs in sex and maturation.

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We prove the equivalence of many-gluon Green's functions in the Duffin-Kemmer-Petieu and Klein-Gordon-Fock statistical quantum field theories. The proof is based on the functional integral formulation for the statistical generating functional in a finite-temperature quantum field theory. As an illustration, we calculate one-loop polarization operators in both theories and show that their expressions indeed coincide.

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Cathepsin D, a lysosomal aspartic protease, has been purified from porcine liver using a combination of pepstatin-A agarose and Affi-Gel Blue affinity chromatography, followed by size-exclusion chromatography. The purified protein consists of two polypeptide chains of 15 and 30 kDa, and has an isoelectric point of 6.8. Porcine liver cathepsin D has maximum activity at pH 2.5-3.0 as determined by its activity against hemoglobin, with a K-cat of 14.3 s(-1) and a k(cat)/K-M of 2.70 x 10(6) s(-1) M-1 as determined by the hydrolysis of a fluorogenic peptide substrate.

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We examined the relationship between food patch size and feeding party size with comparative data from two populations of muriquis (Brachyteles arachnoides) in the 37,797-ha forest at the Parque Estadual de Carlos Botelho (PECB), São Paulo, and the 800-ha forest at the Estacao Biologica de Caratinga (EBC), Minas Gerais. Precipitation Mins more abundant and less seasonal at PECB than EBC, and the density of large trees (>25.0 cm) was higher at PECB (206 ha(-1)) than at EBC (132 ha(-1)). At both sites, the size of feeding parties is positively related to the size of food patches, As predicted, food parches at PECB are significantly larger than those at EBC for both fruit and leaf sources. Contrary to expectations, feeding parties were larger at EEC than PECB, the higher population density of muriquis and sympatric primates at EBC may make large associations more advantageous to these muriquis than to muriquis living at lower population densities in PECB.

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This work describes the synthesis, IR and UV-Vis spectroscopic characterization as well the thermal behavior of the [NiCl2(HIPz)(4)]center dot C3H6O (1), [Ni(H2O)(2)(HIPz)(4)](NO3)(2) (2), [Ni(NCS)(2)(HIPz)(4)] (3) and [Ni(N-3)(2)(HIPz)(4)] (4) (HIPz = 4-iodopyrazole) pyrazolyl complexes. TG experiments reveal that the compounds 1-4 undergo thermal decomposition in three or four mass loss steps yielding NiO as final residue, which was identified by X-ray powder diffraction.

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A research about arthropode fauna in laying hen excrement was carried out in a poultry house in the State of São Paulo, from January 2001 to December 2002. The objective was to verify the frequency of Diptera and Coleoptera collected by Berlese funil and flutuation methods, and to show correlation between the collect methods and sazonality possible in the currents seasons. A total of 29,499 insects were collected from seventy five collects, being 16,702 Diptera (six families) and 12,797 Coleoptera (four families). Some arthropodes presented direct relation with the collect method, the seasons of the years and the rainfall precipitation, with significant increase in the number of insects collected in certain periods of the year.

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

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Cisplatin is a potent drug used in clinical oncology but causes spermatogenesis damage. Amifostine is a drug used against toxicity caused by ionizing irradiation and chemotherapeutic drugs. Since cisplatin provokes fertility and induces germ cell apoptosis and necrosis, we proposed to evaluate the amifostine cytoprotective action on testes of cisplatin-treated rats. Thirty-day-old prepubertal Wistar rats received a single cisplatin dose of 5 mg/kg and were killed after 3, 6, and 12 hr. The hematoxylin-eosin stained testicular sections were submitted to histological, morphometric, and stereological analysis. The terminal deoxynucleotidyl transferase-mediated deoxyuridinetriphosphate nick end-labeling (TUNEL) method was used to label apoptotic cells. TUNEL-positive and TUNEL-negative germ cells with abnormal nuclear morphology (ANM) were scored. Significant alterations of greater part of the parameters occurred in the cisplatin-treated group (CE) compared to the group that received amifostine before the cisplatin-treatment (ACE); however, testicular weight and volume did not vary between these groups. Tubular diameter was reduced in CE in comparison to ACE rats, while interstitial tissue and lymphatic space volume and volume density were significantly higher in CE rats; interstitial testicular edema probably occurred in cisplatin-treated rats. CE rats showed important histological alterations, which were more accentuated than in ACE rats. The numerical densities of apoptotic germ cells and TUNEL-negative cells with ANM were lower in ACE than in CE rats. In conclusion, the amifostine previously administered to prepubertal rats reduced the testicular damage caused by cisplatin. We conclude that amifostine partially protected the rat seminiferous epithelium against cisplatin toxicity.

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Polypropylene powder and sisal fibers were oxygen plasma treated, and the mechanical properties of their composites were tested. Two main effects were investigated: the incorporation of oxygen polar groups in the polypropylene surface and the surface degradation and chain scission of both polypropylene and sisal fibers. Prior to these treatments, three reactor configurations were tested to investigate the best condition for both effects to occur in PP film. Results showed that polypropylene-cellulose adhesion forces are about an order of magnitude higher for PP film treatments at 13.56 MHz than at 40 kHz owing to much higher chain scission at lower frequencies, although it probably also occurs at high frequency and high power. Polypropylene powder treated with oxygen plasma in optimum conditions for polar group incorporation did not result in improvement in any composite mechanical property, probably owing to the polymer melting. Sisal fibers and PP powder treated In conditions of surface degradation did not improve flexural or tensile properties but resulted in higher impact resistance, comparable to the improvement obtained with the addition of compatibilizer.