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The loss of sperm quality in sterlet (Acipenser ruthenus) due to freeze-thaw process in cryopreservation was investigated in the present study. Two antifreeze proteins (AFPI or AFPIII) were used at different concentrations of 0.1, 1, 10, and 100 μg/mL. We compared motility, curvilinear velocity, and plasma membrane integrity of fresh, cryopreserved sperm, and sperm cryopreserved in the presence of antifreeze proteins. Fresh sperm (control) had 85?±?4% motility and 160?±?2 μm/s curvilinear velocity, respectively. After cryopreservation, the motility of frozen-thawed sperm without addition of antifreeze proteins significantly decreased (44?±?9%), compared to the control. The highest motility of frozen-thawed sperm was obtained in cryopreserved sperm with addition of 1 μg/mL of AFPIII (58?±?14%). No significant differences were observed in curvilinear velocity between fresh sperm and cryopreserved sperm with/without addition of AFPI or AFPIII. The flow cytometry analysis revealed that fresh sperm contained 94.5?±?6% live cells, while the cryopreserved sperm only contained 26.6?±?14% live cells. Supplementation of antifreeze proteins has significantly improved the percentage of live cells in frozen-thawed sperm, except 0.1 μg/ml of AFPI group. No significant difference in percentage of live cells was detected in the sperm cryopreserved with 10 μg/mL of AFPI or AFPIII, compared to fresh sperm. Thus, addition of antifreeze proteins to cryopreservation medium could be considered to improve the post-thawed sperm quality of sterlet.  相似文献   
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At the European scale, soil characteristics are needed to evaluate soil quality, soil health and soil-based ecosystem services in the context of the European Green Deal. While some soil databases exist at the European scale, a much larger wealth of data is present in individual European countries, allowing a more detailed soil assessment. There is thus an urgent and crucial need to combine these data at the European scale. In the frame of a large European Joint Programme on agricultural soils launched by the European Commission, a survey was conducted in the spring of 2020, in the 24 European participating countries to assess the existing soil data sources, focusing on agricultural soils. The survey will become a contribution to the European Soil Observatory, launched in December 2020, which aims to collect metadata of soil databases related to all kind of land uses, including forest and urban soils. Based upon a comprehensive questionnaire, 170 soil databases were identified at local, regional and national scales. Soil parameters were divided into five groups: (1) main soil parameters according to the Global Soil Map specifications; (2) other soil chemical parameters; (3) other physical parameters; (4) other pedological parameters; and (5) soil biological features. A classification based on the environmental zones of Europe was used to distinguish the climatic zones. This survey shows that while most of the main pedological and chemical parameters are included in more than 70% of the country soil databases, water content, contamination with organic pollutants, and biological parameters are the least frequently reported parameters. Such differences will have consequences when developing an EU policy on soil health as proposed under the EU soil strategy for 2023 and using the data to derive soil health indicators. Many differences in the methods used in collecting, preparing, and analysing the soils were found, thus requiring harmonization procedures and more cooperation among countries and with the EU to use the data at the European scale. In addition, choosing harmonized and useful interpretation and threshold values for EU soil indicators may be challenging due to the different methods used and the wide variety of soil land-use and climate combinations influencing possible thresholds. The temporal scale of the soil databases reported is also extremely wide, starting from the '20s of the 20th century.  相似文献   
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This paper sets out to clarify the factors in soil erosion and soil conservation. The Czech Republic struggles with soil conservation. Shifts in the rural economy, the loss of good-quality agricultural soil to urbanisation, and sub-optimal land management leading to erosion are at issue. Here, we apply quantitative and qualitative methods to assess erosion risk, whilst considering legislative and policy measures and the responsibility of individual farmer. The studied area was the cadastral district of Rtyně-Podkrkono?í. This choice was based on the fact that farmland there is classified as being subject to ‘no risk’ under current reference measures with regard to soil erosion, and yet 18 erosion events in this area were reported over a period of three years. Our results provide evidence that current measures are insufficient. Although applicable standards were followed, the farmland in question has undergone repeated erosion, whilst soil conservation practice has been ineffective. Compared to the farmland owner, who invests in long-term management, we highlight the problem when a land manager prefers short-term returns. Our assessment of soil erosion was focused on repeated erosion reports that were filed in the monitoring system in relation to farmland parcels managed by a company specialising in maize production. The tolerable erosion rate of 4/t/ha/y was exceeded on all land parcels.  相似文献   
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The effect of dibutyryl cyclic adenosine-3′,5′-monophosphate (DBcAMP) on the activity of aryl hydrocarbon hydroxylase (AHH) was studied under in vivo conditions in the liver of female rats. To maintain an elevated level of DBcAMP for a longer period of time, the nucleotide was given by a continuous infusion up to 26 hr without disturbing the animals. Under these conditions the basal activity of AHH was not significantly changed, indicating that cAMP is not an inducer or inhibitor of AHH. On the other hand, 3-methylcholanthrene-and phenobarbital-mediated induction of AHH was reduced in the presence of DBcAMP by about 50 and 35%, respectively. A reduced induction rate of AHH has also been seen after the application of the herbicide atrazine, which increases the endogenous level of cAMP. The results suggest that cAMP is not involved in the induction of AHH caused by xenobiotics. The inhibitory effect of DBcAMP on the induction of AHH may be due to an inhibition of enzyme synthesis which, in turn, may be the consequence of a direct effect of DBcAMP or an indirect effect caused by changes in the level of steroid hormones.  相似文献   
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Two malting hulled varieties (Sebastian, Malz) and one nonmalting hull-less variety (AF Lucius) were used to assess vitamins C and E in the green biomass of young plants of spring barley ( Hordeum vulgare L.) in three stages of growth and development (BBCH 29, 31, 32-33). The samples from sampling I (BBCH 29) had statistically significantly higher vitamin C content and vitamin E activity compared to sampling I (BBCH 31). The highest average vitamin content was determined in the malting variety Sebastian (vitamin C, 520 mg 100 g(-1) DM; vitamin E, 73.06 mg kg(-1) DM) compared to the varieties Malz (501 mg 100 g(-1) DM; 61.84 mg kg(-1) DM) and AF Lucius (508 mg 100 g(-1) DM; 67.81 mg 100 g(-1) DM). The locality Krome?r?i?z? (Czech Republic, CR), with vitamin C and E contents of 524 mg 100 g(-1) DM and 68.74 mg kg(-1) DM, respectively, proved to be more suitable for growing green biomass compared to the locality Z?abc?ice (CR) (content of vitamins C and E, 477 mg 100 g(-1) DM and 66.39 mg kg(-1) DM, respectively). During the research period (2005-2007), it was determined that the green mass of young plants of spring barley was a significant source of vitamins C and E in the growth stage BBCH 29; in later samplings (BBCH 32-33) the vitamin levels dropped (by as much as 48%). These vitamins are important antioxidants for human health. Therefore, "green barley" can be recommended for the preparation of natural dietary supplements and is preferred to synthetic vitamin preparations.  相似文献   
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Plant Foods for Human Nutrition - The composition of garlic (Allium sativum L.) may vary among cultivars and, moreover, change over time, thereby affecting both biological activity and flavour....  相似文献   
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