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Bioactive compounds are used in the design and development of new food products with potential health benefits, although little is known regarding their bioavailability and interactions. This study assessed the stability, in vitro bioaccessibility, and human bioavailability of β-cryptoxanthin from β-cryptoxanthin-rich drinks with and without added phytosterols developed for this purpose. The developed drinks showed no difference in the content of β-cryptoxanthin, and they were stable over 6 months. In vitro, hydrolysis of β-cryptoxanthin esters and the amount of free β-cryptoxanthin at duodenal and micellar phases were similar regardless of the presence of phytosterols. In the human study, the daily intake provoked significant increments of β-cryptoxanthin in serum regardless of the type of the drink. In conclusion, in vitro and in vivo human studies have shown that the bioavailability of β-cryptoxanthin is not significantly affected by the presence of phytosterols when they are simultaneously supplied in a drink.  相似文献   

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Twenty years ago, Desender and Turin (1989) analysed the changes in the composition of carabid beetles in four NW European countries between the periods <1950 and 1950-1985. Recently, a new distribution atlas of carabid beetles in Belgium was compiled using data collected during the period 1986-2008. In the light of the Countdown2010 target of halting the loss of biodiversity, we used these new data to test whether or not previously observed trends were altered. Since 1950, 46 species were no longer recorded in Belgium and seven species were added to the Belgian fauna. By relating the changes in distribution area to ecological and life history traits as well as to conservation priorities of the species, we examined which species characteristics were associated with the strongest changes in distribution. Comparing the period before 1950 with the period 1950-1985 showed that species from nutrient-poor dry biotopes and heathlands, threatened, rare and big species declined. Generalists, non-threatened species, species with a pan-European distribution range, species in the centre of their distribution range and common species, on the other hand, increased. From the period 1950-1985 to 1986-2008, mainly macropterous species, both rare and very common species and big species decreased, while generalists, dimorphic species, species with a pan-European distribution range and species that were already common in the second period increased. For the conservation of carabid beetles in a strongly industrialised and highly fragmented NW European landscape, we propose actions on two levels: first, the protection and adequate management of high quality biotopes, especially nutrient-poor grasslands and heathlands, in large core areas for specialist species and second, the creation and/or restoration of a ‘matrix’ that facilitates the exchange of individuals between core areas for the conservation of both generalist and specialist species.  相似文献   

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This study assesses the effect of salinity in bioavailability and toxicity of Zn by means of laboratory bioassays by observing contamination in both sediment and water, accumulation of Zn in biological tissues, and histopathological damage in the gills and guts tissues of Ruditapes philippinarum clams, which were exposed to different types of sediments from the Gulf of Cádiz (SW Spain) as well as two dilutions of toxic mud coming from an accidental mining spill. With this objective, the coefficients of distribution (K D) for Zn between overlying water and sediments were calculated, the histopathological frequencies in the tissues of the gills and guts of clams were determined, and the biota-sediment bioaccumulation factors as well as the bioaccumulation factors were quantified in the different stations. Results showed that the greatest histopathological damages appeared when the salinity values decreased. Statistical results showed that salinity was inversely correlated with histopathological damage (p?<?0.01) for the lesion index for gills. The most outstanding results were observed in the two dilutions of toxic mud (0.3% and 7.9%) at a salinity value of 10. Salinity was inversely correlated with the concentration of Zn in biological tissues (p?<?0.05) and inversely correlated with the concentration of Zn in water and sediment. Zn mobilization to the overlying water is produced when salinity values decrease.  相似文献   

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Transactions of the Chinese Society of Agricultural Engineering sponsored by the ChineseSociety of Agricultural Engineering ( CSAE) is a national excellent academic journal,whichintroduces the latest scientific achievements and developing trends of Agricultural Engineering( AE) and providesthe academic developments abroad and athome of the discipline.Itisunder theleadership of China Association for Science and Technology.The Transactions of the CSAE wasstarted in Beijing in May 1 985…  相似文献   

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The aim of the study was to investigate how the quality of snow varies within a city. The study area is situated in the Luleå municipality, in northern Sweden (lat. 65°35′N and long. 22°10′E). For this study, the city was divided into three different types of areas: housing areas, city centre and outskirts. In one area of each type, sampling sites were selected. Snow samples were taken at nine occasions, once every fourteenth day in the city centre and in the housing area. Analyses were carried out for pH, conductivity, suspended solids and both the total and dissolved concentration of phosphorus and selected metals. It was concluded that traffic or activities related to traffic were a major source of heavy metals and phosphorus in urban snow, both in the city centre and in the housing area. Also, the type of area and the design of the street were important for the quality of snow. A clear relation was found between the pH and the quantity of suspended solids in the snow. Higher pH values were found in snow samples from sites with higher traffic loads, and lower pH values at sites, which were the no-traffic sites, with small quantities of particles. The particulate and dissolved substances in the snow behaved in different ways.  相似文献   

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The mobility and migration capacity of Zn in the soil-plant system were studied in a series of pot experiments with barley as a test plant. The parameters of Zn accumulation depending on the metal concentrations in soils and soil solutions were estimated by soil and water culture methods. Experiments with barley in water culture were performed on a nutrient (soil) solution extracted from soddy-podzolic soil (Albic Retisol (Loamic, Ochric)) to which Zn2+ was added to reach working concentrations increasing from 0.07 to 430 μM. Different responses of barley plants to changes in the concentration of Zn in the studied soil were identified. Ranges of the corresponding concentrations in the soil and aboveground barley biomass were determined. Parameters of Zn accumulation by test plants were determined depending on the metal content in soddypodzolic soil and the soil solution. A new method was proposed for evaluating the buffer capacity of soils with respect to a heavy metal (Zn) using test plants (BCS(P)Zn). The method was used to evaluate the buffering capacity of loamy sandy soddy-podzolic soil. The considered methodological approach offers opportunities for using data obtained during the agroecological monitoring of agricultural lands with heavy metals (HMs), including the contents of exchangeable HMs and macroelements (C and Mg) in soils and concentrations of HMs and (Ca + Mg) in plants, in the calculation of the buffering capacity of the surveyed soils for HMs.  相似文献   

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Eurasian Soil Science - The postagrogenic dynamics of organic carbon (Corg), total nitrogen (Ntot), and density fractions of organic matter (OM) in the dark gray soil (Haplic Phaeozem, Belgorod...  相似文献   

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Eurasian Soil Science - The results of morphosubstantive genetic study of a soil–sedimentary sequence with four buried soils in the Boguty River basin (southeastern Altai) are discussed. A...  相似文献   

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Diagnostic features of a catastrophic aridization of climate, desertification, and paleoecological crisis in steppes of the Lower Volga region have been identified on the basis of data on the morphological, chemical, and microbiological properties of paleosols under archeological monuments (burial mounds) of the Middle Bronze Age. These processes resulted in a certain convergence of the soil cover with transformation of zonal chestnut (Kastanozems) paleosols and paleosolonetzes (Solonetz Humic) into specific chestnut-like eroded saline calcareous paleosols analogous to the modern brown desert-steppe soils (Calcisols Haplic) that predominated in this region 4300–3800 years ago.1 In the second millennium BC, humidization of the climate led to the divergence of the soil cover with secondary formation of the complexes of chestnut soils and solonetzes. This paleoecological crisis had a significant effect on the economy of the tribes in the Late Catacomb and Post-Catacomb time stipulating their higher mobility and transition to the nomadic cattle breeding.  相似文献   

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Experience in irrigation of chernozems in the steppe zone of Russia for a period from 1950 to 1990 is analyzed. By the end of this period and in the subsequent years, the areas under irrigation reduced considerably, and the soil productivity worsened. This was caused by the improper design of irrigation systems, on the one hand, and by the low tolerance of chernozems toward increased moistening upon irrigation, on the other hand. The analysis of the factors and regimes of soil formation under irrigation conditions shows that irrigation-induced changes in the soil hydrology also lead to changes in the soil physicochemical, biochemical, and other properties. In particular, changes in the composition of exchangeable cations lead to the development of solonetzic process. In many areas, irrigation of chernozems was accompanied by the appearance of solonetzic, vertic, saline, and eroded soils. The development of soil degradation processes is described. In general, the deterioration of irrigated chernozems was related to the absence of adequate experience in irrigation of steppe soils, unskilled personnel, improper regime of irrigation, and excessively high rates of watering. In some cases, the poor quality of irrigation water resulted in the development of soil salinization and alkalization. To improve the situation, the training of personnel is necessary; the strategy of continuous irrigation should be replaced by the strategy of supplementary irrigation in the critical periods of crop development.  相似文献   

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Exploitation of wildlife for meat in the tropics (‘bushmeat’) is a critical threat for biodiversity, particularly in Africa. Here, we investigate the importance of protected areas (National Parks and other forest parks) as sources for the trade by exploring patterns in pricing and condition of bushmeat carcasses. We surveyed carcass prices in a large sample of trading points (87 markets surveyed, over a 35,000 km2 area) in Cameroon and Nigeria in the Cross–Sanaga region of West Africa. We assessed evidence for national parks as the source of animals traded as bushmeat. The study area included rural and urban centers (Calabar, Nigeria, and Douala, Cameroon) close to important protected areas: the Cross River National Park in Nigeria, and Korup National Park in Cameroon. Both parks host very high species diversity, including a range of endemics. Prices increased with distance from national park boundaries, particularly in Cameroon, where parks may be less depleted than in Nigeria. There was evidence that trading points closer to parks were more likely to function as wholesalers, with meat moving onto further trading points, rather than being sold to the end consumer. Carcasses were more often smoked (a treatment aimed at preservation) if they were not sold to their final consumers; smoking was also commoner at larger trading points. Prices were higher close to the road network, where opportunities for further trade were more available. We consider how wildlife harvests in and around protected areas may be managed to minimize depletion of animal populations, and if protected areas may, on the principle of marine no-take zones, be sustainable sources for regulated harvests.  相似文献   

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Eurasian Soil Science - Despite the widespread use of the taxon “mesotrophic (transitional) peat soils” in the present-day Russian and foreign pedology, including some fundamental...  相似文献   

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