Microcystins (MCYSTs) isolated from blue-green algae,are hepatotoxic polypeptides.It will induce severe intrahepatic hemorrhage and liver necrosis at low concentrations in rats and mice.MCYST- LR is one of MCYSTs whic...Microcystins (MCYSTs) isolated from blue-green algae,are hepatotoxic polypeptides.It will induce severe intrahepatic hemorrhage and liver necrosis at low concentrations in rats and mice.MCYST- LR is one of MCYSTs which consists of 2 variable L- amino acids(leucine and arginine),3 D-amino acids and 2 unusualamino acids(including Adda).MCYSTs bind to protein phosphatase 1 and 2A,and strongly inhibit their activities.The resultant increase of phosphoprotein was referred to be involved in tumor-promoting activity in liver.According to the above results and animal study,MCYST-LR is a potent liver tumor promoter.There were 9 positive from 30 samples of pond-ditch water in high endemic county-Haimen by high-peformance liquid chromatograph and 3 already confirmed by liquid chromograph/mass spectrometer.The quantities of MCYSTs were different between drinking water of liver cancer cases and controls groups.122±0.057and 0.072±0.044μg/200ml respectively) by ELISA. It is not easy to remove by conventional water treatment procedures.The relationship between MCYSTs and oncogenes and anti-oncogenes are under studying.展开更多
CCC plasmid was isolated from an economically important blue-green alga- Spirulina platensis (1.7×106 dalton from the S6 strain and 1.2×106 dalton from the F, strain) using a rapid method based on ultrasonic...CCC plasmid was isolated from an economically important blue-green alga- Spirulina platensis (1.7×106 dalton from the S6 strain and 1.2×106 dalton from the F, strain) using a rapid method based on ultrasonic disruption of algal cells and alkaline removal of chromosomal DNA. The difference in the molecular weight of the OOC DNAs from the two strains differing in form suggests that plasmid may be related with the differentiation of algal form. This modified method, which does not use any lysozyme, is a quick and effective method of plasmid isolation, especially for filamentous blue-green algae.展开更多
Based on the experience and lessons from previous control of lakes, as well as the present situation of water eutrophication and outbreak of blue-green algae in lakes, general ideas of controlling outbreak of blue-gre...Based on the experience and lessons from previous control of lakes, as well as the present situation of water eutrophication and outbreak of blue-green algae in lakes, general ideas of controlling outbreak of blue-green algae in large and middle lakes were proposed. Firstly, it is needed to control serious outbreak of blue-green algae and then build health aquatic ecosystems and corresponding control goals finally. Secondly, quantity of blue-green algae in lakes and lake eutrophication should be reduced at the same time. Thirdly, quantity of reduced blue-green algae must exceed the natural increase of them in quantity persistently, so that outbreak of blue-green algae will reduce and even be eliminated. Fourthly, engineering measures and corresponding safeguard measures to control outbreak of blue-green algae in lakes should be combined.展开更多
Since the water supply crisis in the Taihu Lake on May 29,2007,the control of the Taihu Lake has achieved remarkable results,and the eutrophication has been greatly reduced.Existing problems are as follows:outbreaks o...Since the water supply crisis in the Taihu Lake on May 29,2007,the control of the Taihu Lake has achieved remarkable results,and the eutrophication has been greatly reduced.Existing problems are as follows:outbreaks of blue-green alga still appear seriously every year,and there is no goal to eliminate outbreaks of blue-green alga;the load into the lake greatly exceeds the environmental capacity;reed wetlands are greatly reduced;there is still the possibility of a water supply crisis;the research of eliminating outbreak of blue-green alga is weak.In this paper,the experience of controlling the Taihu Lake is summarized,and the ultimate goals of eliminating eutrophication and outbreaks of blue-green alga and restoring wetlands and biodiversity are proposed.Control measures are proposed,such as deepening the promotion of the lake chief system,establishing the lake chief system in an all-round way,and increasing applied scientific and technological efforts and capital investment.The necessity and possibility of further controlling the Taihu Lake to eliminate outbreaks of blue-green alga should be recognized.Relying on controlling eutrophication alone cannot eliminate outbreaks of blue-green alga.The point that phosphorus control is the key to eliminate outbreaks of blue-green alga is not suitable for the Taihu Lake.The integration ideas of"three types"of technologies should be innovated.The first one is"double reduction and double increase"measures to eliminate eutrophication,of which"double reduction"is to reduce external point sources and non-point sources and internal blue-green alga in sediment;for external sources,the treatment standard of sewage plants should be paid special attention to.The second one is"double algae removal"measures to salvage blue-green alga,suppresses and kills algae.The blue-green alga on the surface,middle and bottom of water should be thoroughly salvaged and eliminated from various water areas.The third one is"double restoration"measures to restore wetlands and biodiversity.The area of wetlands should be restored to the area from the 1960s to the 1970s before outbreaks of blue-green alga,and vegetation coverage reaches 25%-30%.The Taihu Lake is controlled in different waters to ensure water supply safety in water sources.Five suggestions are proposed,such as revising the"Overall Plan for the Comprehensive Treatment of Water Environment in the Taihu Lake Basin"again,incorporating the goal of eliminating outbreaks of blue-green alga in the plan,setting up this research topic,greatly improving sewage treatment standards in local legislation.展开更多
城市生态环境质量的监测和评价对于城市可持续发展具有重要意义。为评价我国近海发达城市近年来生态环境质量,该文以南京市为例,基于2021年Sentinel-2A遥感影像,利用绿色空间、蓝色空间、建筑及不透水地表面构建了一种新的遥感绿色指数(...城市生态环境质量的监测和评价对于城市可持续发展具有重要意义。为评价我国近海发达城市近年来生态环境质量,该文以南京市为例,基于2021年Sentinel-2A遥感影像,利用绿色空间、蓝色空间、建筑及不透水地表面构建了一种新的遥感绿色指数(remote sensing green index,RSGI)模型,并初次将模型应用于南京市的生态环境质量评价。首先,对南京市Sentinel-2A遥感影像进行神经网络监督分类,构建RSGI,用于评价南京市各区的生态环境质量;其次,运用皮尔逊相关系数分析了RSGI与城市各生态要素之间的相关性;最后运用聚合层次聚类分析法分析了南京市各区之间的相似程度。结果表明:南京市生态环境质量呈现出中间低四周高的结构,其中六合区RSGI值最高(0.86),秦淮区最低(0.38),相差0.48;RSGI与绿色空间密度呈现0.01级别正相关趋势,与人口密度、建筑密度、不透水地表面密度呈现0.01级别负相关趋势;南京市11个区在城市生态要素方面以70%相似度为阈值可划分为4个集合,第一集合为秦淮区、鼓楼区和建邺区,第二集合为雨花台区和栖霞区,第三集合为玄武区和高淳区,第四集合由其他4个区组成。研究结果可为南京市未来城市规划与可持续发展提供科学依据。展开更多
基于2000-2020年土地利用类型数据,采用景观指数、景观动态度、地理探测器等方法,分析沿黄城市泰安市蓝绿空间时空演变特征及其驱动因素。结果表明,1)近20 a泰安市蓝绿空间规模整体呈减少趋势,动态度为-0.41%,面积减少131.24 km 2,但呈...基于2000-2020年土地利用类型数据,采用景观指数、景观动态度、地理探测器等方法,分析沿黄城市泰安市蓝绿空间时空演变特征及其驱动因素。结果表明,1)近20 a泰安市蓝绿空间规模整体呈减少趋势,动态度为-0.41%,面积减少131.24 km 2,但呈现明显的阶段性特征,前10 a变化剧烈,动态度为-0.82%,后10 a动态度仅为0.005%。2)2000-2020年,蓝绿空间景观格局指数发生了显著变化,且各指数在前10 a的变化程度更大;类型水平上,绿色空间和蓝色空间的景观形状整体趋于规则、均有连片发展趋势,但绿色空间的景观形状更复杂、分布离散度更大;景观水平上,蓝绿空间破碎度呈减弱趋势,但景观连通性下降、景观异质性增强。3)地理探测分析表明,社会经济因素是蓝绿空间分异的主导因子,生产总值、人口密度、第一与第二产业产值等社会经济因素对蓝绿空间变化的解释力显著大于高程等自然因素。研究认为城镇化进程中需要加强对国土空间的科学管控,应加强泰安市蓝绿空间的完整性、连通性保护。该研究为泰安市蓝绿空间优化与管理、区域可持续发展提供一定参考。展开更多
A more exact model of phycobilisomes has been designed with the rods composed of the hexamer disks and an abstract allophycocyanin (APC) core. Based on this model, the excitation energy transfer was simulated using th...A more exact model of phycobilisomes has been designed with the rods composed of the hexamer disks and an abstract allophycocyanin (APC) core. Based on this model, the excitation energy transfer was simulated using the computer simulation technique. The simulation shows that the excitation energy is transferred from the outlayer disk to the core in a partly reversible way in phycobilisomes, and that the transfer rate from the last disk to the core is less than those between disks. The energy transfer between the two trimers in a hexamer is dominantly through the α84-chromophores (m), while that between the disks is through the β84-chromophores (f) that are also responsible for the transfer of energy into the core.展开更多
文摘Microcystins (MCYSTs) isolated from blue-green algae,are hepatotoxic polypeptides.It will induce severe intrahepatic hemorrhage and liver necrosis at low concentrations in rats and mice.MCYST- LR is one of MCYSTs which consists of 2 variable L- amino acids(leucine and arginine),3 D-amino acids and 2 unusualamino acids(including Adda).MCYSTs bind to protein phosphatase 1 and 2A,and strongly inhibit their activities.The resultant increase of phosphoprotein was referred to be involved in tumor-promoting activity in liver.According to the above results and animal study,MCYST-LR is a potent liver tumor promoter.There were 9 positive from 30 samples of pond-ditch water in high endemic county-Haimen by high-peformance liquid chromatograph and 3 already confirmed by liquid chromograph/mass spectrometer.The quantities of MCYSTs were different between drinking water of liver cancer cases and controls groups.122±0.057and 0.072±0.044μg/200ml respectively) by ELISA. It is not easy to remove by conventional water treatment procedures.The relationship between MCYSTs and oncogenes and anti-oncogenes are under studying.
基金This research was supported in part by The President of The Chinese Academy of Sciences Foundation
文摘CCC plasmid was isolated from an economically important blue-green alga- Spirulina platensis (1.7×106 dalton from the S6 strain and 1.2×106 dalton from the F, strain) using a rapid method based on ultrasonic disruption of algal cells and alkaline removal of chromosomal DNA. The difference in the molecular weight of the OOC DNAs from the two strains differing in form suggests that plasmid may be related with the differentiation of algal form. This modified method, which does not use any lysozyme, is a quick and effective method of plasmid isolation, especially for filamentous blue-green algae.
文摘Based on the experience and lessons from previous control of lakes, as well as the present situation of water eutrophication and outbreak of blue-green algae in lakes, general ideas of controlling outbreak of blue-green algae in large and middle lakes were proposed. Firstly, it is needed to control serious outbreak of blue-green algae and then build health aquatic ecosystems and corresponding control goals finally. Secondly, quantity of blue-green algae in lakes and lake eutrophication should be reduced at the same time. Thirdly, quantity of reduced blue-green algae must exceed the natural increase of them in quantity persistently, so that outbreak of blue-green algae will reduce and even be eliminated. Fourthly, engineering measures and corresponding safeguard measures to control outbreak of blue-green algae in lakes should be combined.
文摘Since the water supply crisis in the Taihu Lake on May 29,2007,the control of the Taihu Lake has achieved remarkable results,and the eutrophication has been greatly reduced.Existing problems are as follows:outbreaks of blue-green alga still appear seriously every year,and there is no goal to eliminate outbreaks of blue-green alga;the load into the lake greatly exceeds the environmental capacity;reed wetlands are greatly reduced;there is still the possibility of a water supply crisis;the research of eliminating outbreak of blue-green alga is weak.In this paper,the experience of controlling the Taihu Lake is summarized,and the ultimate goals of eliminating eutrophication and outbreaks of blue-green alga and restoring wetlands and biodiversity are proposed.Control measures are proposed,such as deepening the promotion of the lake chief system,establishing the lake chief system in an all-round way,and increasing applied scientific and technological efforts and capital investment.The necessity and possibility of further controlling the Taihu Lake to eliminate outbreaks of blue-green alga should be recognized.Relying on controlling eutrophication alone cannot eliminate outbreaks of blue-green alga.The point that phosphorus control is the key to eliminate outbreaks of blue-green alga is not suitable for the Taihu Lake.The integration ideas of"three types"of technologies should be innovated.The first one is"double reduction and double increase"measures to eliminate eutrophication,of which"double reduction"is to reduce external point sources and non-point sources and internal blue-green alga in sediment;for external sources,the treatment standard of sewage plants should be paid special attention to.The second one is"double algae removal"measures to salvage blue-green alga,suppresses and kills algae.The blue-green alga on the surface,middle and bottom of water should be thoroughly salvaged and eliminated from various water areas.The third one is"double restoration"measures to restore wetlands and biodiversity.The area of wetlands should be restored to the area from the 1960s to the 1970s before outbreaks of blue-green alga,and vegetation coverage reaches 25%-30%.The Taihu Lake is controlled in different waters to ensure water supply safety in water sources.Five suggestions are proposed,such as revising the"Overall Plan for the Comprehensive Treatment of Water Environment in the Taihu Lake Basin"again,incorporating the goal of eliminating outbreaks of blue-green alga in the plan,setting up this research topic,greatly improving sewage treatment standards in local legislation.
文摘城市生态环境质量的监测和评价对于城市可持续发展具有重要意义。为评价我国近海发达城市近年来生态环境质量,该文以南京市为例,基于2021年Sentinel-2A遥感影像,利用绿色空间、蓝色空间、建筑及不透水地表面构建了一种新的遥感绿色指数(remote sensing green index,RSGI)模型,并初次将模型应用于南京市的生态环境质量评价。首先,对南京市Sentinel-2A遥感影像进行神经网络监督分类,构建RSGI,用于评价南京市各区的生态环境质量;其次,运用皮尔逊相关系数分析了RSGI与城市各生态要素之间的相关性;最后运用聚合层次聚类分析法分析了南京市各区之间的相似程度。结果表明:南京市生态环境质量呈现出中间低四周高的结构,其中六合区RSGI值最高(0.86),秦淮区最低(0.38),相差0.48;RSGI与绿色空间密度呈现0.01级别正相关趋势,与人口密度、建筑密度、不透水地表面密度呈现0.01级别负相关趋势;南京市11个区在城市生态要素方面以70%相似度为阈值可划分为4个集合,第一集合为秦淮区、鼓楼区和建邺区,第二集合为雨花台区和栖霞区,第三集合为玄武区和高淳区,第四集合由其他4个区组成。研究结果可为南京市未来城市规划与可持续发展提供科学依据。
基金Project supported by the National Natural Science Foundtion of China.
文摘A more exact model of phycobilisomes has been designed with the rods composed of the hexamer disks and an abstract allophycocyanin (APC) core. Based on this model, the excitation energy transfer was simulated using the computer simulation technique. The simulation shows that the excitation energy is transferred from the outlayer disk to the core in a partly reversible way in phycobilisomes, and that the transfer rate from the last disk to the core is less than those between disks. The energy transfer between the two trimers in a hexamer is dominantly through the α84-chromophores (m), while that between the disks is through the β84-chromophores (f) that are also responsible for the transfer of energy into the core.
