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91.
Fabiola G. Arcos Ana María Ibarra María del Carmen Rodríguez-Jaramillo Ethel Awilda García-Latorre & Celia Vazquez-Boucard 《Aquaculture Research》2009,40(6):644-655
The oyster's reproductive process is poorly documented, especially in terms of a quantitative approach. In recent years, investigations with this species have been directed at determining important reproductive factors. Within this scope, techniques that allow standardized and accurate quantitative estimations of gonad development have become of primary importance. In this study, the histological characteristics and the levels of vitellin/vitellogenin-like proteins (Vn/Vtg) from ovaries of the Mexican Pacific 'pleasure' oyster Crassostrea corteziensis (Hertlein 1951) were analysed during different stages of gonad maturation using quantitative histological techniques and an enzyme-linked immunosorbent assay. This was performed in order to evaluate a possible quantitative tool to predict the degrees of gonad maturity and to analyse the biological implications of the findings relative not only to broodstock conditioning but also to natural populations. Using this information, we expect to be able to undertake further research on different reproductive aspects of this oyster species, including, among others, evaluation of the response in Vn/Vtg concentrations to different diets and environmental conditions during laboratory conditioning. 相似文献
92.
Thomas F Randet C Gilbert A Silvestre V Jamin E Akoka S Remaud G Segebarth N Guillou C 《Journal of agricultural and food chemistry》2010,58(22):11580-11585
Until now, no analytical method, not even isotopic ones, had been able to differentiate between sugars coming from C4-metabolism plants (cane, maize, etc.) and some crassulacean acid metabolism plants (e.g., pineapple, agave) because in both cases the isotope distributions of the overall carbon-13/carbon-12 and site-specific deuterium/hydrogen isotope ratios are very similar. Following recent advances in the field of quantitative isotopic carbon-13 NMR measurements, a procedure for the analysis of the positional carbon-13/carbon-12 isotope ratios of ethanol derived from the sugars of pineapples and agave using the site-specific natural isotopic fractionation-nuclear magnetic resonance (SNIF-NMR) method is presented. It is shown that reproducible results can be obtained when appropriate analytical conditions are used. When applied to pineapple juice, this new method demonstrates a unique ability to detect cane and maize sugar, which are major potential adulterants, with a detection limit in the order of 15% of the total sugars, which provides an efficient mean of controlling the authenticity of juices made from this specific fruit. When applied to tequila products, this new method demonstrates a unique ability to unambiguously differentiate authentic 100% agave tequila, as well as misto tequila (made from at least 51% agave), from products made from a larger proportion of cane or maize sugar and therefore not complying with the legal definition of tequila. 相似文献
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Beltrame Renato Travassos Morais Junior Nilson Nunes Careta Joao Vitor Pagoto Ribeiro Ariádna Patricia Lima Thales Alves Dutra da Costa Ricardo Lopes Dias Quirino Celia Raquel 《Tropical animal health and production》2020,52(2):503-509
Tropical Animal Health and Production - Twenty-eight pluriparous and non-lactating Santa Inês sheep were synchronized with vaginal sponge and an intramuscular (IM) injection of... 相似文献
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Live fences are common elements in neotropical agricultural landscapes and could play important roles in the conservation
of biodiversity by enhancing landscape connectivity, however, little is known about their abundance and spatial arrangement.
The objectives of this study were to characterize the abundance and spatial patterns of live fences in a fragmented landscape
dominated by pastures in Río Frío, Costa Rica, to determine their contribution to landscape structure and connectivity and
to examine their role as tools for landscape conservation planning. Live fences accounted for 45.4% of all fences in the landscape
and occurred with a mean density of 50.5 linear meters per hectare. Although live fences covered only a small total area of
the landscape (<2%), they had an important effect on landscape structure and connectivity, increasing total tree cover, dividing
pastures into smaller areas, creating rectilinear networks that cross the landscape and providing direct physical connections
to forest patches. Simulations showed that the conversion of all existing wooden fences to live fences would greatly enhance
landscape connectivity by more than doubling the area, density and number of direct connections to forest habitats, and reducing
the average distance between tree canopies. Our study demonstrates that live fences play key roles in defining the structure
and composition of neotropical agricultural landscapes and merit consideration in both conservation efforts and agricultural
policies designed to enhance landscape connectivity and promote biodiversity conservation. 相似文献
99.
Mitjans M del Campo J Abajo C Martínez V Selga A Lozano C Torres JL Vinardell MP 《Journal of agricultural and food chemistry》2004,52(24):7297-7299
We examined the potential antioxidant activity and the immunopharmacological activity of new epicatechin conjugates obtained by depolymerization of grape polymeric flavanols in the presence of cysteamine or cysteine and with or without gallate. The compounds studied were (-)-epicatechin (1), cysteinyl-epicatechin (2), cysteamine-epicatechin (3), (-)-epicatechin gallate (4), cysteinyl-epicatechin gallate (5), and cysteamine-epicatechin gallate (6) When incubated with an erythrocyte suspension, flavanols protected the erythrocyte membrane from hemolysis induced by 2,2'-azobis(2-amidinopropane) dihydrochloride, an azo free-radical initiator. All the epicatechin derivatives tested were more efficient as antioxidant than epicatechin. The most potent antioxidant was compound 6. The compounds were tested for their capacity to modulate IL-1beta and IL-6, which are the main cytokine factors influencing the acute phase of the inflammatory response. (-)-Epicatechin and its related compounds inhibited the production of IL-1beta and IL-6 in whole blood incubated in the presence of Escherichia coli lipopolysaccharide. The most efficient inhibitor of cytokine formation was compound 3. 相似文献
100.
M. Cristina Forti Adilson Carvalho Adolpho J. Melfi Celia R. Montes 《Water, air, and soil pollution》2001,130(1-4):1121-1126
SO4 2?, NO3 ? and H+ depositions are estimated in the Brazilian territory based on the existing rainfall chemical data and on annual rainfall distribution over the whole territory. Local and regional depositions are estimated. Rainfall chemical data over the Braziliian territory shows that the average pH values are usually low (between 4.0 and 5.5). These values are observed in the tropical Amazon forest as well as in urban areas. However, the rainwater acidity in the tropical forests are due to organic acids naturally produced by the vegetation while in urban areas the acidity is mainly due to acidic anion deposition (NO3 ? and SO4 2?). In some Amazonian areas, the average input values through rainfall for NO3 ? is about 0.06 keq.ha.yr?1 and for SO4 2? is between 0.23 and 0.54 keq.ha?1.yr?1. On the other hand, in some urban centers, such as São Paulo, values of .072 keq.ha?1.yr?1 for NO3 ? and 1.16 keq.ha?1.yr?1 of SO4 2? are found and in sites where sulfate sources (coal mining) are present, as for the area of Florianópolis, values as high as 5.59 keq.ha?1.yr?1 for SO4 2? are found. 相似文献