本研究旨在比较不同土地利用数量预测方法的适用性,并结合空间分布预测模型对香溪河流域未来的土地利用进行预测,以期为该区域的土地利用规划提供决策支持,有效控制总磷污染负荷的产生。结合土地利用数量预测的3种算法(线性外推法、马...本研究旨在比较不同土地利用数量预测方法的适用性,并结合空间分布预测模型对香溪河流域未来的土地利用进行预测,以期为该区域的土地利用规划提供决策支持,有效控制总磷污染负荷的产生。结合土地利用数量预测的3种算法(线性外推法、马尔科夫链模型以及遗传算法)与空间预测模型CLUE-S(Conversion of land use and its effect at small regional extent),对流域内的土地利用变化进行预测,通过输出系数法对流域内的总磷污染负荷进行估算。结果表明,基于线性外推与马尔科夫链两种无约束预测模型,2020年流域内林地面积将比2010年减少约1%,绝大多数林地转变为水田与旱地,且大多发生在流域中部坡度较平缓区域。而基于存在自然社会经济约束条件的遗传算法优化情景下,水田面积减少1060 hm2、旱地面积减少3370 hm2,其面积主要转化为林地,且大多发生在流域高海拔、较陡峭的北部区域。基于输出系数法分析得到的流域内总磷污染负荷在线性外推与马尔科夫链预测情景下相比于2010年均有所增加,分别增加11 000 kg和8000 kg,而在遗传算法情景下,总磷负荷相比于2010年减少约24 000kg。空间分布上,在线性外推与马尔科夫链情景下增加的负荷主要位于流域中部区域,而在遗传算法情景下流域北部区域总磷负荷减少量最为明显。研究结果表明,遗传算法在土地利用优化预测方面表现优异,结合CLUE-S模型,可以对未来土地利用规划起到一定的支持作用,有效控制非点源污染负荷的产生。展开更多
OBJECTIVE Only limited number of drugs are currently available for treating ischemic stroke.Therapeutic angiogenesis has recently emerged as one of the most promising therapies for cerebral ischemic injury.Isopropyl-...OBJECTIVE Only limited number of drugs are currently available for treating ischemic stroke.Therapeutic angiogenesis has recently emerged as one of the most promising therapies for cerebral ischemic injury.Isopropyl-β-(3,4-dihydroxyphenyl)-α-hydroxypropanoate(IDHP)is a metabolite derived from the botanical formulation for Dantonic®.Here,we investigated the angiogenic efficacy of IDHP in cerebral ischemia.METHODS The in vivo effects of IDHP were evaluated in the C57BL/6 mouse Matrigel plug and rat transient middle cerebral artery occlusion(tMCAO)models.Primary human umbilical vein endothelial cells(HUVEC)and human brain microvascular endothelial cells(HBMEC)were used to explore the effects of IDHP on stimulating proliferation,migration and tube formation in vitro.ELISA and Western blotting were used to quantitate the release and expression of relevant target molecules and signaling pathways.RESULTS IDHP reduced infarct volume and improved sensorimotor function in rats subjected to tMCAO by promoting angiogenesis,and promoted Matrigel neovascularization in mice.Moreover,IDHP produced a biphasic modulation on proliferation and migration both in HUVEC and HBMEC.It also induced tube formation in a 12-day HUVEC-HDF co-culture model and in Matrigel assays.IDHP-induced angiogenesis was accompanied by increased levels of p-AMPKα(Thr172)and p-eNOS(Ser1177)both in vitro and in vivo,and the decreased level of VEGF in rat brains on day 1 whereas enhanced level of VEGF on day 3 and 7 after tMCAO.Mechanistically,AMPK knockdown or pharmacologically inhibiting AMPK and its upstream kinases(CaMKKβ)inhibited the eNOS phosphorylation induced by IDHP in HUVEC.Furthermore,selective eNOS inhibitor(L-NIO),selective CaMKKβinhibitor(STO)and AMPKa inhibitor(Compound C)blocked the capillary-like tube formation in the co-culture model induced by IDHP(10 nmol·L^(-1)).CONCLUSION Collectively,these findings showed that IDHP protected rats from cerebral ischemia-reperfusion injury by promoting angiogenesis via activating CaMKKβ/AMPK(Thr172)/eNOS(Ser1177)signaling,and suggest it to be a promising new drug candidate for the prevention and/or treatment of cerebral ischemia and other vascular occlusive diseases.展开更多
文摘本研究旨在比较不同土地利用数量预测方法的适用性,并结合空间分布预测模型对香溪河流域未来的土地利用进行预测,以期为该区域的土地利用规划提供决策支持,有效控制总磷污染负荷的产生。结合土地利用数量预测的3种算法(线性外推法、马尔科夫链模型以及遗传算法)与空间预测模型CLUE-S(Conversion of land use and its effect at small regional extent),对流域内的土地利用变化进行预测,通过输出系数法对流域内的总磷污染负荷进行估算。结果表明,基于线性外推与马尔科夫链两种无约束预测模型,2020年流域内林地面积将比2010年减少约1%,绝大多数林地转变为水田与旱地,且大多发生在流域中部坡度较平缓区域。而基于存在自然社会经济约束条件的遗传算法优化情景下,水田面积减少1060 hm2、旱地面积减少3370 hm2,其面积主要转化为林地,且大多发生在流域高海拔、较陡峭的北部区域。基于输出系数法分析得到的流域内总磷污染负荷在线性外推与马尔科夫链预测情景下相比于2010年均有所增加,分别增加11 000 kg和8000 kg,而在遗传算法情景下,总磷负荷相比于2010年减少约24 000kg。空间分布上,在线性外推与马尔科夫链情景下增加的负荷主要位于流域中部区域,而在遗传算法情景下流域北部区域总磷负荷减少量最为明显。研究结果表明,遗传算法在土地利用优化预测方面表现优异,结合CLUE-S模型,可以对未来土地利用规划起到一定的支持作用,有效控制非点源污染负荷的产生。
基金National Natural Science Foundation of China(31971143)and Primary R&D Plan of Shaanxi Province(2021KWZ-24)。
文摘OBJECTIVE Only limited number of drugs are currently available for treating ischemic stroke.Therapeutic angiogenesis has recently emerged as one of the most promising therapies for cerebral ischemic injury.Isopropyl-β-(3,4-dihydroxyphenyl)-α-hydroxypropanoate(IDHP)is a metabolite derived from the botanical formulation for Dantonic®.Here,we investigated the angiogenic efficacy of IDHP in cerebral ischemia.METHODS The in vivo effects of IDHP were evaluated in the C57BL/6 mouse Matrigel plug and rat transient middle cerebral artery occlusion(tMCAO)models.Primary human umbilical vein endothelial cells(HUVEC)and human brain microvascular endothelial cells(HBMEC)were used to explore the effects of IDHP on stimulating proliferation,migration and tube formation in vitro.ELISA and Western blotting were used to quantitate the release and expression of relevant target molecules and signaling pathways.RESULTS IDHP reduced infarct volume and improved sensorimotor function in rats subjected to tMCAO by promoting angiogenesis,and promoted Matrigel neovascularization in mice.Moreover,IDHP produced a biphasic modulation on proliferation and migration both in HUVEC and HBMEC.It also induced tube formation in a 12-day HUVEC-HDF co-culture model and in Matrigel assays.IDHP-induced angiogenesis was accompanied by increased levels of p-AMPKα(Thr172)and p-eNOS(Ser1177)both in vitro and in vivo,and the decreased level of VEGF in rat brains on day 1 whereas enhanced level of VEGF on day 3 and 7 after tMCAO.Mechanistically,AMPK knockdown or pharmacologically inhibiting AMPK and its upstream kinases(CaMKKβ)inhibited the eNOS phosphorylation induced by IDHP in HUVEC.Furthermore,selective eNOS inhibitor(L-NIO),selective CaMKKβinhibitor(STO)and AMPKa inhibitor(Compound C)blocked the capillary-like tube formation in the co-culture model induced by IDHP(10 nmol·L^(-1)).CONCLUSION Collectively,these findings showed that IDHP protected rats from cerebral ischemia-reperfusion injury by promoting angiogenesis via activating CaMKKβ/AMPK(Thr172)/eNOS(Ser1177)signaling,and suggest it to be a promising new drug candidate for the prevention and/or treatment of cerebral ischemia and other vascular occlusive diseases.
