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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
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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
96.
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
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OBJECTIVE: To assess validity of the Nambour food-frequency questionnaire (FFQ) relative to weighed food records (WFRs), and the extent to which selected demographic, anthropometric and social characteristics explain differences between the two dietary methods.DESIGN: Inter-method validity study; 129-item FFQ vs. 12 days of WFR over 12 months.SETTING: Community-based Nambour Skin Cancer Prevention Trial.SUBJECTS: One hundred and fifteen of 168 randomly selected participants in the trial (68% acceptance rate) aged 25-75 years.RESULTS: Spearman correlations between intakes from the two methods ranged from 0.18 to 0.71 for energy-adjusted values. Differences between FFQ and WFR regressed on personal characteristics were significantly associated with at least one characteristic for 16 of the 21 nutrients. Sex was significantly associated with differences for nine nutrients; body mass index (BMI), presence of any medical condition and age were each significantly associated with differences for three to six nutrients; use of dietary supplements and occupation were associated with differences for one nutrient each. There was no consistency in the direction of the significant associations. Regression models explained from 7% (riboflavin) to 27% (saturated fat) of variation in differences in intakes.CONCLUSIONS: The relative validity of FFQ estimates for many nutrients is quite different for males than for females. Age, BMI, medical condition and level of intake were also associated with relative validity for some nutrients, resulting in the need to adjust intakes estimates for these in modelling diet-disease relationships. Estimates for cholesterol, beta-carotene equivalents, retinol equivalents, thiamine, riboflavin and calcium would not benefit from this. 相似文献
98.
Suárez-Pantaleón C Mercader JV Agulló C Abad-Somovilla A Abad-Fuentes A 《Journal of agricultural and food chemistry》2008,56(23):11122-11131
The development of immunoassays for the detection of the plant growth regulator forchlorfenuron (CPPU) is described. To achieve that purpose, a set of CPPU derivatives has been obtained by the previous synthesis of the adequate p-aminophenyl alkanoic acid. Protein conjugates of these compounds have been used as immunogens to produce rabbit polyclonal antibodies and a collection of mouse monoclonal antibodies. Additionally, a battery of structural analogues of the target analyte has been synthesized and used for the characterization of antibody binding. This strategy has demonstrated that most antibodies followed Landsteiner's principle, although some monoclonal antibodies showing important deviations from this behavior have also been found. Finally, different assay formats have been developed with a variety of antibodies and conjugates, and a rapid procedure has been optimized for the indirect ELISA format using monoclonal and polyclonal antibodies. In the indirect competitive ELISA, assay IC50 values for CPPU below 0.5 nM were found with LODs as low as 0.013 nM. 相似文献
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Sastre Blanca Barbero-Sierra Celia Bienes Ramón Marques Maria Jose García-Díaz Andrés 《Journal of Soils and Sediments》2017,17(3):873-888
Journal of Soils and Sediments - Soil erosion is a threat for the sustainability of the grove production all over the world, and olive groves are where the highest erosion is achieved. This study... 相似文献