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Ashton MJ, Layzer JB. Summer microhabitat use by adult and young‐of‐year snail darters (Percina tanasi) in two rivers. Ecology of Freshwater Fish 2010: 19: 609–617. © Published 2010. This article is a US Government work and is in the public domain in the USA. Abstract – We characterised microhabitat availability and use by adult and young‐of‐year (YOY) snail darters (Percina tanasi Etnier 1976 ) while snorkelling in the French Broad and Hiwassee rivers, TN, USA. Both age groups of snail darters disproportionately used most microhabitat variables compared to their availability. Snail darters primarily occupied moderately deep, swift water over gravel substrates with little macrophyte coverage and no silt. Univariate comparisons indicated that adult and YOY darters occupied different habitat, but there was no marked differences between principal components analysis plots of multivariate microhabitat use within a river. Although the availability of microhabitat variables differed between the French Broad and Hiwassee rivers, univariate means and multivariate plots illustrated that the habitats used were generally similar by age groups of snail darters between rivers. Because our observations of habitat availability and use were constrained to low flow periods and depths <1 m, the transferability of our results to higher flow periods may be limited. However, the similarity in habitat use between rivers suggests that our results can be applied to low‐normal flow conditions in other streams. 相似文献
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试验结果表明,发光网线应用于被动性张网渔具时,增产效果不明显,而且还必须考虑资源保护和解决光源激发问题。在拖网渔具上应用时,能提高渔获效率,夜间生产效果高于白天,而且调整方便。 相似文献
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Lee AW Chen TL Shih CM Huang CY Tsao NW Chang NC Chen YH Fong TH Lin FY 《Journal of agricultural and food chemistry》2010,58(24):12941-12949
Ursolic acid (UA), a triterpenoid compound found in plants, is used in the human diet and in medicinal herbs and possesses a wide range of biological benefits including antioxidative, anti-inflammatory, and anticarcinogenic effects. Endothelial expression of allograft inflammatory factor-1 (AIF-1) mediates vasculogenesis, and nitric oxide (NO) produced by endothelial NO (eNOS) represents a mechanism of vascular protection. It is unclear whether UA affects the neovascularization mediated by AIF-1 and eNOS expression. This study investigated the effects and mechanisms of UA on angiogenesis in vivo in hind limb ischemic animal models and in vitro in human coronary artery endothelial cells (HCECs). This study explored the impact of UA on endothelial cell (EC) activities in vitro in HCECs, vascular neovasculogenesis in vivo in a mouse hind limb ischemia model, and the possible role of AIF-1 in vasculogenesis. The results demonstrate that UA enhances collateral blood flow recovery through induction of neovascularization in a hind limb ischemia mouse model. In vitro data showed that UA increases tube formation and migration capacities in human endothelial cells, and exposing HCECs to UA increased AIF-1 expression through a NO-related mechanism. Moreover, UA administration increased capillary density and eNOS and AIF-1 expression in ischemic muscle. These findings suggest that UA may be a potential therapeutic agent in the induction of neovascularization and provide a novel mechanistic insight into the potential effects of UA on ischemic vascular diseases. 相似文献
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本文对40个云南高原甘薯地方品种种薯萌芽特性进行了比较研究,结果表明:“易门黄皮”、“蒙自黄心”、“卷叶”、“紫红皮”、“普洱黄山芋”、“红鸡窝”、“路南红皮”、“樱枝”、东川白花”等一批云南甘薯地方品种种薯萌芽能力强,出苗较早,幼苗生长状况较好,是选育甘薯新品种的重要亲本材料,亦可在生产上直接利用。 相似文献
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Constructive Approaches to Intellectual Property Complexity in Today's Agricultural Technology World
Essential to progress in plant biotechnology for deliverable applications patent patent application data must be transparent in order to determine where there is whitespace for innovation.…… 《分子植物育种》2007,5(2):299-300
Essential to progress in plant biotechnology for deliverable applications, patent and patent application data must be transparent in order to determine where there is whitespace for innovation. 相似文献
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