The survival of Dunhuang Oasis is largely determined by the evolution of sand dunes in the southern edge of the oasis, mainly composed of shield dunes and mega pyramid dunes, which occupy twothirds and one-third of th...The survival of Dunhuang Oasis is largely determined by the evolution of sand dunes in the southern edge of the oasis, mainly composed of shield dunes and mega pyramid dunes, which occupy twothirds and one-third of the area, respectively. However, few studies have focused on dynamics of these dunes, especially in terms of quantification. So the theoretical basis of sand-control engineering is relatively limited. Here we present the characteristics of dune dynamics of a shield dune and mega pyramid dune in the southern edge of Dunhuang Oasis during April 2014-April 2016 based on measurement data of a 3-D laser scanner. Results indicate that the volume of the shield dune decreased during the monitoring period of two years, and the gravity centers of the monitored shield dune moved windward, indicating that sand was transported toward the oasis. Conversely, the dune volume of the mega pyramid dune increased and the gravity center presented no prominent movement, indicating that the megapyramid dune was relatively stable and its migration toward the oasis was not notable. Thus, compared with mega pyramid dunes, shield dunes in the southern edge of Dunhuang Oasis are identified as a more significant sand source endangering the protection of the oasis, and sand-control engineering should mainly focus on these shield dunes.展开更多
The periphery of oasis plays an important role in mutual transformation between desert and oasis. Vegetation is an important part in the ecosystem and it is an important index indicating certain landscape, Based on se...The periphery of oasis plays an important role in mutual transformation between desert and oasis. Vegetation is an important part in the ecosystem and it is an important index indicating certain landscape, Based on several times field investigation, this paper attaches importance to the feasible measures for vegetation restoration according to the current condition of study area - Qira County of Xinjiang Uygur Autonomous Region, In order to improve die local ecological environment, people lived in Qira County should work bard to protect their homehind and reduce the degree of sandstorm, More protection forest should be established along with other ecological techniques. Results derived from this study contribute largely to the ecological environmental protection of oasis.展开更多
AIM： To evaluate the antioxidant and phase II detoxification enzyme inducing ability of green leaf vegetables consumed in Asia.METHODS： The antioxidant properties of six commonly consumed Asian vegetables were deter...AIM： To evaluate the antioxidant and phase II detoxification enzyme inducing ability of green leaf vegetables consumed in Asia.METHODS： The antioxidant properties of six commonly consumed Asian vegetables were determined using the ABTS, DPPH, deoxyribose, PR bleaching and ironascorbate induced lipid peroxidation assay. Induce of phase II detoxification enzymes was also determined for each respective vegetable extract. Protection against authentic ONOO- and HOCl mediated cytotoxicity in human colon HCT116 cells was determined using the MTT 3-（4,5-dimethylthiazol-2-yl）-2,5-diphenyl tetrasodium bromide） viability assay.RESULTS： All of the extracts derived from green leaf vegetables exhibited antioxidant properties, while also having cytoprotective effects against ONOO- and HOCI mediated cytotoxicity. In addition, evaluation of the phase II enzyme inducing ability of each extract, as assessed by quinone reductase and glutathione- S-transferase activities, showed significant variation between the vegetables analyzed.CONCLUSION： Green leaf vegetables are potential sources of antioxidants and phase II detoxification enzyme inducers in the Asian diet. It is likely that consumption of such vegetables is a major source of beneficial phytochemical constituents that may protect against colonic damage.展开更多
基金supported by the National Natural Sciences Foundation of China(Grant No.41871016)the National Key Research and Development Program of China(Grant No.2017YFC0504801)+1 种基金Opening Fund of Key Laboratory of Desert and Desertification,Chinese Academy of Sciences(Grant No.KLDD-2017-007)Technology research and development program of China Railway Urumqi Group Co.,Ltd.(2017J002,2017J003)
文摘The survival of Dunhuang Oasis is largely determined by the evolution of sand dunes in the southern edge of the oasis, mainly composed of shield dunes and mega pyramid dunes, which occupy twothirds and one-third of the area, respectively. However, few studies have focused on dynamics of these dunes, especially in terms of quantification. So the theoretical basis of sand-control engineering is relatively limited. Here we present the characteristics of dune dynamics of a shield dune and mega pyramid dune in the southern edge of Dunhuang Oasis during April 2014-April 2016 based on measurement data of a 3-D laser scanner. Results indicate that the volume of the shield dune decreased during the monitoring period of two years, and the gravity centers of the monitored shield dune moved windward, indicating that sand was transported toward the oasis. Conversely, the dune volume of the mega pyramid dune increased and the gravity center presented no prominent movement, indicating that the megapyramid dune was relatively stable and its migration toward the oasis was not notable. Thus, compared with mega pyramid dunes, shield dunes in the southern edge of Dunhuang Oasis are identified as a more significant sand source endangering the protection of the oasis, and sand-control engineering should mainly focus on these shield dunes.
基金National Natural Science Foundation of China （Grant No.40261006） West Light Foundation of The Chinese Academy of Science, Xinjiang Universities Scientific Research Plan （Grant No. XJEDU2004S03, XJEDU2005107） Doctoral Start Fund of Xinjiang University.
文摘The periphery of oasis plays an important role in mutual transformation between desert and oasis. Vegetation is an important part in the ecosystem and it is an important index indicating certain landscape, Based on several times field investigation, this paper attaches importance to the feasible measures for vegetation restoration according to the current condition of study area - Qira County of Xinjiang Uygur Autonomous Region, In order to improve die local ecological environment, people lived in Qira County should work bard to protect their homehind and reduce the degree of sandstorm, More protection forest should be established along with other ecological techniques. Results derived from this study contribute largely to the ecological environmental protection of oasis.
文摘AIM： To evaluate the antioxidant and phase II detoxification enzyme inducing ability of green leaf vegetables consumed in Asia.METHODS： The antioxidant properties of six commonly consumed Asian vegetables were determined using the ABTS, DPPH, deoxyribose, PR bleaching and ironascorbate induced lipid peroxidation assay. Induce of phase II detoxification enzymes was also determined for each respective vegetable extract. Protection against authentic ONOO- and HOCl mediated cytotoxicity in human colon HCT116 cells was determined using the MTT 3-（4,5-dimethylthiazol-2-yl）-2,5-diphenyl tetrasodium bromide） viability assay.RESULTS： All of the extracts derived from green leaf vegetables exhibited antioxidant properties, while also having cytoprotective effects against ONOO- and HOCI mediated cytotoxicity. In addition, evaluation of the phase II enzyme inducing ability of each extract, as assessed by quinone reductase and glutathione- S-transferase activities, showed significant variation between the vegetables analyzed.CONCLUSION： Green leaf vegetables are potential sources of antioxidants and phase II detoxification enzyme inducers in the Asian diet. It is likely that consumption of such vegetables is a major source of beneficial phytochemical constituents that may protect against colonic damage.
