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The Alliance for Freshwater Life: A global call to unite efforts for freshwater biodiversity science and conservation 
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下载免费PDF全文 William Darwall Vanessa Bremerich Aaike De Wever Anthony I. Dell Jörg Freyhof Mark O. Gessner Hans‐Peter Grossart Ian Harrison Ken Irvine Sonja C. Jähnig Jonathan M. Jeschke Jessica J. Lee Cai Lu Aleksandra M. Lewandowska Michael T. Monaghan Jens C. Nejstgaard Harmony Patricio Astrid Schmidt‐Kloiber Simon N. Stuart Michele Thieme Klement Tockner Eren Turak Olaf Weyl 《水产资源保护:海洋与淡水生态系统》2018,28(4):1015-1022
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Aleksandra Ukalska‐Jaruga Agnieszka Klimkowicz‐Pawlas Boena Smreczak 《Soil Use and Management》2019,35(4):595-606
The objective of this study was to investigate differences in organic matter fractions, such as dissolved organic carbon and humic substances, in soils under different land uses. Soil samples were collected from the upper layer of arable lands and grasslands. Humic substances (HS) were chemically fractionated into fulvic acids (FA), humic acids (HA) and humins (HUM), and based on the separated fractions, the humification index (HI) and the degree of HS transformation (DT) were calculated. Dissolved organic carbon (DOC) was determined by cold (CWE) and hot water (HWE) extractions. Regardless of land use, the results indicated significant differences in soil organic carbon (SOC) and HS composition, with HA and HUM as the dominant fractions. Total SOC was higher in grassland (median = 17.51 g kg?1) than arable soils (median = 9.98 g kg?1); the HI and DT indices did not differ significantly between land uses (HI = 0.3–10.3 and DT = 0.2–6.2 for grasslands, p > 0.05; HI = 0.3–3.9 and DT = 0.2–20.1 for arable lands, p > 0.05). This indicates the relatively high stability of organic carbon and efficient humification processes in both land uses. Additionally, in arable soils lower CWE‐C (0.75 g kg?1) and higher HWE‐C (2.59 g kg?1) than in grasslands (CWE‐C = 1.13 g kg?1, HWE‐C = 1.60 g kg?1) can be related to farming practice and application of soil amendments. The results showed that both labile and humified organic matter are better protected in grassland soils and are consequently less vulnerable to mineralization. 相似文献
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Ewa Przedpe?ska-W?sowicz Aleksandra Polatajko Ma?gorzata Wierzbicka 《Water, air, and soil pollution》2012,223(8):5445-5458
We investigated the influence of cadmium stress on zinc hyperaccumulation, mineral nutrient uptake, and the content of metal-binding proteins in Arabidopsis halleri. The experiments were carried out using plants subjected to long-term cadmium exposure (40?days) in the concentrations of 45 and 225???M Cd2+. Inductively coupled plasma-mass spectrometry, size exclusion chromatography coupled with plasma-mass spectrometry, and laser ablation inductively coupled plasma-mass spectrometry used for ablation of polyacylamide gels were employed to assess the content of investigated elements in plants as well as to identify metal-binding proteins. We found that A. halleri is able to translocate cadmium to the aerial parts in high amounts (translocation index >1). We showed that Zn content in plants decreased significantly with the increase of cadmium content in the growth medium. Different positive and negative correlations between Cd content and mineral nutrients were evidenced by our study. We identified more than ten low-molecular-weight (<100?kDa) Cd-binding proteins in Cd-treated plants. These proteins are unlikely to be phytochelatins or metallothioneins. We hypothesize that low-molecular-weight Cd-binding proteins can be involved in cadmium resistance in A. halleri. 相似文献
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Aleksandra Skalec Maciej Janeczek Albert Czerski 《Anatomia, histologia, embryologia》2019,48(5):466-475
Despite the great progress in the field of tendon injuries and chronic tendinopathies in recent years, treatment of these conditions is still challenging. Research utilising animal models is crucial for further advancement in tendon research, with the rabbit being a commonly used species in this field. The objective of the present study was to comprehensively describe the macro‐ and microanatomy of the common calcanean tendon (tendo Achillei), together with associated structures. Eight female New Zealand rabbits were subjected to anatomical dissection and histologic analysis, revealing significant species‐specific features. The soleus muscle presented a thin, spindle shape with no tendon of insertion and attached directly to the lateral gastrocnemius muscle. Therefore, it does not contribute to the formation of the common calcanean tendon. The calcaneal tendon of the semitendinosus muscle was identified as a strong tendinous band at the medial side of the medial gastrocnemius muscle and the superficial digital flexor muscle and tendon distally. The saphenous artery was accompanied by the medial saphenous vein and characteristic accessory medial saphenous vein. The complex structure of the paratendinous connective tissue is described, with the paratenon being contiguous with the epitenon of the individual tendons and epimysium of associated muscles. At the level of the calcaneal tuber, the retromalleolar fat pad was identified, adhering to the cranial surface of the conjoint gastrocnemius tendon. Histologic studies confirmed the presence of the subtendinous calcaneal bursa of superficial digital flexor tendon and the bursa of calcaneal tendon. 相似文献
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由于地域广阔性和气候环境差异性,俄罗斯植物园在世界范围内具有独特地位,不仅是植物科学研究、物种保护和科普教育机构,同时也是城市、区域乃至国家的文化艺术特色与活力的展示媒介。文章以俄罗斯10个著名植物园为研究对象,从结构布局、科学研究、植物保护与展示、景观建筑4个层面探讨其地域特色营造方法,从区位交通、资源集聚、市民活动3方面分析其活力营造策略,旨在为我国植物园的发展与建设提供借鉴。 相似文献
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AbstractIn many northern regions frost hardiness of new cultivars of woody plants and perennials is fundamental for nursery production and the greenery industry. This study was conducted to determine the effect of calcium fertilization on frost resistance of Forsythia sp. cultivars. Plants were sprayed five times at four week intervals with calcium nitrate 1?g of (Ca(NO3)2). 100?ml H2O?1 per shrub. Shoots were frozen at three temperatures: –20, –25, and –30?°C. In all cases the chlorophyll content index in the leaves, and the calcium (Ca2+) content in leaves and stems of forsythia cultivars were significantly higher when calcium nitrate supplementation was provided. The Ca2+content in the roots was not affected. The freezing temperature had a great effect on the stem frost damage of tested forsythia cultivars. The greatest damage was observed after freezing at –30?°C. However, tissue damage of plants that were sprayed with calcium nitrate was considerably less evident, and cross sections of stems looked significantly better. At the lowest temperatures (–25 and –30?°C) a positive effect of calcium fertilization on lower electrolyte leakage was observed in all tested cultivars. Fertilization with finely ground calcium nitrate increased stem freezing tolerance of forsythia tested cultivars, especially new ones which have stems that are more susceptible to frost damage. 相似文献
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Piotrowska KK Woclawek-Potocka I Bah MM Piskula MK Pilawski W Bober A Skarzynski DJ 《The Journal of reproduction and development》2006,52(1):33-41
The aim of this study was to examine whether active metabolites of phytoestrogens (equol and para-ethyl-phenol) inhibit sensitivity of bovine corpus luteum (CL) to luteinizing hormone (LH) and to auto/paracrine luteotropic factors (prostaglandin E2-PGE2 and prostaglandin F(2alpha)-PGF(2alpha)), and whether they influence pulsatile progesterone (P4) secretion by the bovine CL. In in vivo experiments, high levels of equol and para-ethyl-phenol were found in plasma and in the CL tissue of heifers and cows fed a soy bean diet (2.5 kg/animal/day), along with lower concentrations of P4 (P < 0.05). Both Prostaglandins (PG) and LH strongly stimulated P4 secretion in cultured pieces of CL that were collected from cows fed a standard diet (P < 0.01). There was no effect of PGs and LH on P4 stimulation in CLs obtained from cows fed a diet rich in soy bean. Finally, we examined whether active metabolites of phytoestrogens participated in regulation of pulsatile P4 secretion and LH-stimulated P4 secretion in vitro using a microdialysis system. Equol and para-ethyl-phenol had no effect on basic and pulsatile P4 secretion in CLs during 240 min of perfusion when compared to the control (P < 0.05). However, they inhibited LH-stimulated P4 secretion (P < 0.05). Phytoestrogens and their metabolites may disrupt CL function by inhibiting PG- and LH-stimulated P4 secretion. 相似文献
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Aleksandra Szyd?owska-Czerniak Konrad TrokowskiEdward Sz?yk 《Industrial Crops and Products》2011,33(1):123-131
The effects of three independent variables: solvent polarity, temperature and extraction time on the antioxidant capacity, total phenolic content and phenolic acid composition in extracts obtained from sunflower shells before and after enzymatic treatment were studied. Response surface methodology based on three-level, three-variable Box-Behnken design was used for optimization of extraction parameters and evaluation of their effect on antioxidant capacity and total phenolic content in shell extracts.The average antioxidant capacities of extracts from sunflower shells without enzymatic treatment (368.1-1574.4 μmol TE/100 g) were higher than those for cellulolytic and pectolytic enzymes-treated shells (222.7-1419.0 and 270.7-1570.7 μmol TE/100 g, respectively). The content of total phenolic compounds ranged between 58.2-341.2 mg CGA/100 g, 26.7-277.3 mg CGA/100 g and 51.4-301.5 mg CGA/100 g for extracts obtained from shells without enzyme and treated with cellulolytic and pectolytic enzymes, respectively. Total phenolic content (TPC) in the studied shell extracts correlated significantly (p < 0.0001) positively with their antioxidant capacity determined by the ferric reducing antioxidant power (FRAP) method (r = 0.9275). Results of FRAP, TPC and phenolic acid composition in the studied shell extracts depend on the extraction conditions (solvent polarity, temperature, time), but they are independent on the addition of enzyme solutions. The antioxidant capacity and total phenolic content in the resulting extracts increased with a line in extraction temperature and solvent polarity. 相似文献
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