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921.
Jose Antonio Grande Antonio Jiménez Sixto Romero María Luisa de la Torre Tamara Gómez-Olivera 《Water, air, and soil pollution》2010,212(1-4):299-307
In this work, the determination of moving averages is proposed as a method for quantifying metal, arsenic, and sulfate discharges into a water course undergoing acid mine drainage processes which flows into a public water supply dam in the Iberian Pyrite Belt. The analysis of the results obtained by applying moving averages shows that the highest metal and sulfate concentrations occur in October, coinciding with the first rainfall and the sponging of mine dumps, with November and December being the months when the highest contributions to the Andevalo Dam take place. The discharge of acid mine waters with its corresponding metal load into the Andevalo Dam means, for a single hydrological year, more than 6,000 t of sulfates, almost 600 t of iron, and 1 t of As, of special relevance for the hydrochemical quality of the stored waters. When they arrive at the dam, these metals precipitate, since the water pH is near 7, and remain latent in the bottom sediment as long as the chemical makeup of the dam water does not change. 相似文献
922.
923.
Sharpsnout bream (Diplodus puntazzo) has been used in Adriatic aquaculture for less than a decade, but the decreasing trend of rearing this species will probably
result in its complete substitution by more exploited sea bream (Sparus aurata). Only two facilities still rear both fish species in neighbouring cages in monoculture. A switch of parasites was observed
between sparids during monitoring of the gill monogeneans of farmed fish. In wild fish of the Adriatic Sea, Lamellodiscus elegans (Monogenea: Monopisthocotylea) has previously been reported in annular (Diplodus annularis), and two-banded sea bream (D. vulgaris) and sharpsnout bream (D. puntazzo), and the present study confirmed its presence also in sea bream, in low prevalence and abundance. The exclusively sea bream
monogenean Sparicotyle chrysophrii (Monogenea: Polyopisthocotylea) was also isolated from sharpsnout bream, showing prevalence and abundance values even higher
than in its resident host. In the occurrence of L. elegans in sea bream, the opportunistic switch resulted in lower abundance and prevalence than in the original host, while in the
second case of switching the monogenean S. chrysophrii showed better reproductive capacity on a new host (sharpsnout bream). Both cases point to the possible enlargement of parasite
host range. 相似文献
924.
Capuano E Fedele F Mennella C Visciano M Napolitano A Lanzuise S Ruocco M Lorito M del Castillo MD Fogliano V 《Journal of agricultural and food chemistry》2007,55(10):4189-4195
Amadoriase I is a fructosyl amine oxidase from Aspergillus fumigatus that catalyzes the oxidation of Amadori products (APs) producing glucosone, H2O2, and the corresponding free amine. All the enzymes of this family discovered so far only deglycate small molecular weight products and are inactive toward large molecular weight substrates, such as glycated BSA or ribonuclease A. Therefore, they cannot be used to reverse protein glycation occurring in diabetes or in foods. In this paper, the effect of Amadoriase I added during the in vitro reaction between glucose and peptides having different polarities or proteins with molecular weights ranging from to 5 to 66 kDa was tested. The formation of APs was monitored by ESI-MS of intact glycated protein or peptides and by measuring the Nepsilon-(1-deoxy-d-fructos-1-yl)-L-lysine and furosine concentrations. Results showed that the formation of APs is reduced up to 80% when peptides and glucose are incubated in the presence of Amadoriase. The effect is more evident for hydrophobic peptides. In protein-glucose systems, the effect was dependent on the molecular weight and steric hindrance being negligible for BSA and at a maximum for insulin, where the formation of APs was reduced up to 60%. These findings indicate new potential applications of Amadoriase I as an efficient tool for inhibiting protein glycation in real food systems. 相似文献
925.
Baroni MV Chiabrando GA Costa C Fagúndez GA Wunderlin DA 《Journal of agricultural and food chemistry》2004,52(24):7222-7226
We report the development of a rapid, specific, and sensitive enzyme-linked immunoassay (ELISA) for the evaluation of sunflower pollen in honey as a method alternative to melissopalynology, which is considered the standard technique for the evaluation of floral origin of honey. Two 33-36 kDa proteins, identified as characteristic of sunflower pollen, were isolated and used as coating antigens in the competitive ELISA. We verified its analytical performance by evaluating reproducibility, specificity, and exactitude in relation to melissopalynology. The competitive ELISA developed during this work is able to quantify sunflower pollen in honey, with a detection limit of 10%, showing linear response between 10 and 90%. The method afforded low cross reactivity with honey from other floral origin, thus evidencing an adequate selectivity. We also observed a significant correlation (r = 0.975; p < 0.001) when the proposed ELISA was referenced to melissopalynology. Hence, we conclude that the competitive ELISA constitutes a valuable and feasible alternative for authentication of sunflower honey. This work opens the possibility to develop similar assays for other pollen types. 相似文献
926.
Rodríguez García JC Iglesias Rodríguez R Peña Crecente RM Barciela García J García Martín S Herrero Latorre C 《Journal of agricultural and food chemistry》2006,54(19):7206-7212
Thirteen metal elements were determined in 40 honey samples from Galicia with different environmental origins: rural, urban, and industrial areas. The data set of the honey metallic profiles was studied with a double purpose: first, to make a preliminary evaluation of honey as an environmental indicator in Galicia with the aim of monitoring pollution and, second, to compare the different capabilities of diverse pattern recognition prediction procedures for modeling the environmental surrounding of the hive. A certain level of similarity for urban and industrial samples was obtained using principal component analysis and cluster analysis, whereas significant differences for urban and industrial honeys were found in relation to rural honey samples. Different classification rules to associate metal content of honeys with their environmental surrounding were obtained by chemometric pattern recognition procedures. In general, the classification methods developed by neural networks provided better results than the traditional pattern recognition procedures. The metal profiles of honey seem to provide sufficient information to enable categorization criteria for classifying samples according to their environmental surrounding. Thus, honey could be a potential pollution indicator for the Galician area. 相似文献
927.
José Manuel Briceño-Linares Jon Paul Rodríguez Kathryn M. Rodríguez-Clark Franklin Rojas-Suárez Pablo Antonio Millán Eleonora G. Vittori Mar Carrasco-Muñoz 《Biological conservation》2011,(4):1188-1193
The yellow-shouldered parrot (Amazona barbadensis) is listed in Venezuela as Endangered and internationally as Vulnerable, primarily due to poaching for the illegal pet trade. Various interventions have been implemented to reduce poaching (increasing the population from 700 in 1989 to 1600 in 2009), but poaching pressure is still high, and is ever-changing, requiring an evolving response. Between 2000 and 2003, our only intervention was environmental education in schools: in the short term, unsurprisingly, it had no impact on poaching, which reached 100% of nestlings in monitored nests. From 2004 onwards, we implemented a set of new field interventions. In 2004, 24 h field surveillance decreased poaching to 56%. In 2005, the addition of foster nests and a pilot test of “assisted breeding” brought the figure down to 18%. In 2006, assisted breeding was expanded, achieving 0% poaching. In 2007, poachers raided our “secure” site, and took 34 nestlings, bringing poaching up to 60%. A pilot study of artificial nests offered promising results. In 2008 and 2009, the addition of patrolling by local police reduced poaching to 16% and 1%, respectively. During 2004–2009, nestling poaching averaged 25%. Ensuring parrot recruitment in the future will require a combination of the strategies employed to date; in the short term, expanding the use of artificial nests to increase availability of nesting sites in easily-patrolled areas has the most potential to build on past successes. 相似文献
928.
Olguín Héctor F. Puig Alba Loez Carolina R. Salibián Alfredo Topalián Mirta L. Castañé Patricia M. Rovedatti María G. 《Water, air, and soil pollution》2004,155(1-4):355-381
Results of different approaches potentially useful for the evaluation of water ambient quality were analysed and compared in a small temperate lowland river with mixed diffuse and multiple-point source pollution. The Reconquista River (Buenos Aires Province, Argentina), one of the most polluted watercourses of Latin America, receives agrochemicals as well as domestic and industrial (mostly untreated) effluents. Physical and chemical water variables were determined; unispecies algal bioassays (with Chlorella pyrenoidosa and Scenedesmus acutus) were carried out in laboratory; and density and structure of phyto- and zooplankton were analysed at three sites in four dates (representing a range of likely conditions in the river). A general scheme of association among plankton, bioassays and physical/chemical variables was elaborated, that helped to infer possible control factors in this multi-stressed system. Some empirical methods, but mainly mathematical ones including multivariate techniques (as PCA, cluster analysis), were applied for evaluation of samples. A preliminary selection of indices and attributes as potential indicators of the water river quality was made, and then applied for assay a tentative integrative ordination of samples. The relative best water quality was recorded when-where dissolved oxygen concentration, algal diversity and planktonic crustacean density were higher. The worst water quality corresponded to the lack of cladocerans and lowest crustacean density, and higher: organic and industrial pollution, major nutrients (ammonium and orthophosphates), BOD, hardness, conductivity, algal biomass in bioassays, phytoplankton density (>10 000 ind. mL-1), dominance of a single algal species (>90%), and rotifer proportion in zooplankton (>85%). 相似文献
929.
Maela Lupo Brenda L. Fina María C. Aguirre Mirta Armendariz Alfredo Rigalli 《Water, air, and soil pollution》2012,223(8):5221-5225
The upper limit of fluoride concentration in water for human consumption is 1.5?ppm. Many studies have been carried out concerning the water fluoride concentration in wide areas around the world, but none have studied the change of fluoride concentration as a function of geographical coordinates and through time. This paper describes ??microvariation?? of fluoride concentration among wells separated by less than 500?m in a month. On the other hand, ??macrovariation?? is also studied describing changes among cities that are separated by more than 10?km and compared with fluoride concentrations measured 65?years ago. Fluoride concentration was measured in a wide geographical area of Argentina, which is 133,000?km2. Samples of water were collected from different regions. Macrovariation: Differences in fluoride concentration in well water among regions were found, as well as an increase in water fluoride concentration during seven decades. Microvariation: Daily water fluoride concentration in a specific area displayed a great variation in the measurements through time. In addition, wells with no more than 500?m of separation were measured at the same time and were significantly different. These results indicate that in order to determine the fluoride concentration of a region, different samples of the same area should be obtained and a sampling through time should also be done. 相似文献
930.