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991.
Patricia G. Cardoso Eduarda Pereira Tiago F. Grilo Armando C. Duarte Miguel A. Pardal 《Water, air, and soil pollution》2012,223(1):421-428
Mercury bioaccumulation kinetics of two important macrobenthic species, the polychaete Hediste diversicolor and the bivalve Scrobicularia plana, were evaluated following a dietary pathway (i.e. contaminated algae), through a mesocosm laboratory experiment. Both studied
species presented a similar model of Hg bioaccumulation kinetics, a linear pattern of accumulation through time being the
mercury accumulation in the organisms proportional to the mercury concentration in the food. Mercury bioaccumulation rates
were higher in the polychaete H. diversicolor (reaching approximately 0.15 μg g−1 at the end of the experiment) than in the bivalve S. plana (≈0.07 μg g−1), which could be related to their feeding strategies, ingestion rates and assimilation efficiencies. Moreover, the mercury
bioaccumulation revealed to be quite a fast process especially for the polychaete, and despite the fact that this species
is not an edible organism, it is an important prey item, which can greatly contribute to the transport of contaminants to
higher trophic levels. Therefore, the bioaccumulation of mercury by these important macrobenthic species, especially the bivalves,
represents a non-negligible risk for humans. 相似文献
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993.
Maria Gabriela Baracat Sanchez José Marques Jr. Diego Silva Siqueira Livia Arantes Camargo Gener Tadeu Pereira 《Precision Agriculture》2013,14(2):201-214
Predicting and mapping productivity areas allows crop producers to improve their planning of agricultural activities. The primary aims of this work were the identification and mapping of specific management areas allowing coffee bean quality to be predicted from soil attributes and their relationships to relief. The study area was located in the Southeast of the Minas Gerais state, Brazil. A grid containing a total of 145 uniformly spaced nodes 50 m apart was established over an area of 31.7 ha from which samples were collected at depths of 0.00–0.20 m in order to determine physical and chemical attributes of the soil. These data were analysed in conjunction with plant attributes including production, proportion of beans retained by different sieves and drink quality. The results of principal component analysis (PCA) in combination with geostatistical data showed the attributes clay content and available iron to be the best choices for identifying four crop production environments. Environment A, which exhibited high clay and available iron contents, and low pH and base saturation, was that providing the highest yield (30.4l ha?1) and best coffee beverage quality (61 sacks ha?1). Based on the results, we believe that multivariate analysis, geostatistics and the soil–relief relationships contained in the digital elevation model (DEM) can be effectively used in combination for the hybrid mapping of areas of varying suitability for coffee production. 相似文献
994.
Erwan Plouguerné Lauro M. de Souza Guilherme L. Sassaki Jéssica Figueiredo Cavalcanti Maria Teresa Villela Romanos Bernardo A. P. da Gama Renato Crespo Pereira Eliana Barreto-Bergter 《Marine drugs》2013,11(11):4628-4640
Total lipids from the Brazilian brown seaweed Sargassum vulgare were extracted with chloroform/methanol 2:1 and 1:2 (v/v) at room temperature. After performing Folch partition of the crude lipid extract, the lipids recovered from the Folch lower layer were fractionated on a silica gel column eluted with chloroform, acetone and methanol. The fraction eluted with methanol, presented a strong orcinol-positive band characteristic of the presence of sulfatides when examined by TLC. This fraction was then purified by two successive silica gel column chromatography giving rise to fractions F4I86 and F4II90 that exhibited strong activity against herpes simplex virus type 1 and 2. The chemical structures present in both fractions were elucidated by ESI-MS and 1H/13C NMR analysis HSQC fingerprints based on their tandem–MS behavior as sulfoquinovosildiacylglycerols (SQDGs). The main SQDG present in both fractions and responsible for the anti-herpes activity observed was identified as 1,2-di-O-palmitoyl-3-O-(6-sulfo-α-d-quinovopyranosyl)-glycerol. 相似文献
995.
D.R. Ayres R.J. Pereira A.A. Boligon F.F. Silva F.S. Schenkel V.M. Roso L.G. Albuquerque 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2013,130(6):417-424
Cattle resistance to ticks is measured by the number of ticks infesting the animal. The model used for the genetic analysis of cattle resistance to ticks frequently requires logarithmic transformation of the observations. The objective of this study was to evaluate the predictive ability and goodness of fit of different models for the analysis of this trait in cross‐bred Hereford x Nellore cattle. Three models were tested: a linear model using logarithmic transformation of the observations (MLOG); a linear model without transformation of the observations (MLIN); and a generalized linear Poisson model with residual term (MPOI). All models included the classificatory effects of contemporary group and genetic group and the covariates age of animal at the time of recording and individual heterozygosis, as well as additive genetic effects as random effects. Heritability estimates were 0.08 ± 0.02, 0.10 ± 0.02 and 0.14 ± 0.04 for MLIN, MLOG and MPOI models, respectively. The model fit quality, verified by deviance information criterion (DIC) and residual mean square, indicated fit superiority of MPOI model. The predictive ability of the models was compared by validation test in independent sample. The MPOI model was slightly superior in terms of goodness of fit and predictive ability, whereas the correlations between observed and predicted tick counts were practically the same for all models. A higher rank correlation between breeding values was observed between models MLOG and MPOI. Poisson model can be used for the selection of tick‐resistant animals. 相似文献
996.
Farias Nadja Naiara Pereira Freitas Ednardo Rodrigues do Nascimento Germano Augusto Jerônimo Xavier Regina Patrícia Souza de Melo Braz Nádia Dantas Francisco Diego Teixeira Figueiredo Carlos Weiber Silva Gomes Valter Luis Maia Watanabe Pedro Henrique 《Tropical animal health and production》2019,51(1):179-185
Tropical Animal Health and Production - The aim of the current study was to evaluate the addition of fresh and stored copra meal to the diet of meat quails. Two hundred eighty-seven-day-old male... 相似文献
997.
Ana Canadas Marta Santos Rui Medeiros Patrícia Dias‐Pereira 《Veterinary and comparative oncology》2019,17(4):489-496
E‐cadherin is a cell adhesion molecule that participates in several cellular processes that guarantee the maintenance of structural and functional integrity of epithelial tissues. E‐cadherin plays an important role in mammary carcinogenesis, and various studies have demonstrated the effect of CDH1 genetic variation in risk, progression and biological behaviour of human breast cancer. Although there are some recognized genetic variations in canine CDH1 gene, their influence in canine mammary tumour development and progression has not been previously evaluated. In this study, we aim to assess the influence of CDH1 SNPs rs850805755, rs852280880 and rs852639930 in the risk, clinicopathological features and clinical outcome of canine mammary tumours. A case‐control study was conducted involving 206 bitches with mammary tumours and 161 bitches free of mammary neoplasia. CDH1 SNPs rs850805755 and rs852280880 were associated with a decreased risk and a later onset of mammary tumour development. Furthermore, these SNPs were related to the development of small size carcinomas, of low histological grade and low nuclear pleomorphism. SNP rs852639930 was associated with the development of small size tumours with a non‐infiltrative, non‐invasive growth pattern. Data from the present investigation demonstrate that these CDH1 genetic variants could have a protective role in canine mammary tumours, by being associated with low risk of tumour development, delayed onset of the disease and less aggressive clinicopathological features. 相似文献
998.
Buffy coat smear or Knott's test: which to choose for canine microfilaria screening in field studies? 下载免费PDF全文
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