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Dynamics of morphological changes for mitochondrial fission and fusion

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Science china(Physics,Mechanics & Astronomy) 2010年第4期53卷 680-689页

作者： WANG ShiQi 1,2.4 , FU ChangLiang 1,2., ZHANG Yan 1,2., CHEN Quan 3.& LONG Mian 1,2.1 Key Laboratory of Microgravity (National Microgravity Laboratory), beijing 100190,{2. 2.Center for Biomechanics and Bioengineering, institute of Mechanics, Chinese {3. of sciences, beijing 100190,{2. 3.State Key Laboratory of Biomembrane and Membrane Biotechnology, institute of Zoology, Chinese {3. of sciences,{12.,{2. 4 institute of Vertebrate Paleontology and Paleoanthropology, Chinese {3. of sciences, beijing 100044,{2. Key Laboratory of Microgravity (National Microgravity Laboratory) Beijing China Center for Biomechanics and Bioengineering Institute of Mechanics Chinese Academy of Sciences Beijing China institute of Vertebrate Paleontology and Paleoanthropology Chinese Academy of Sciences Beijing China State Key Laboratory of Biomembrane and Membrane Biotechnology Institute of Zoology Chinese Academy of Sciences Beijing China

Mitochondria experience continuous fusion and fission in a living cell, but their dynamics remains poorly quantified. Here a theoretical model was developed, upon a simplified population balance equation (PBE), to predict the morphological changes induced by mitochondrial fission and fusion. Assuming that both fission and fusion events are statistically independent, the survival probability of mitochondria staying in the fission or fusion state was formulated as an exponentially-decayed function with time, which depended on the time-dependent distribution of the mitochondrial volume and the fission and fusion rates. Parametric analysis was done for two typical volume distributions. One was Gamma distribution and the other was Gaussian distribution, derived from the measurements of volume distribution for individual mitochondria in a living cell and purified mitochondria in vitro. The predictions indicated that the survival probability strongly depended on morphological changes of individual mitochondria and was inversely correlated to the fission and fusion rates. This work provided a new insight into quantifying the mitochondrial dynamics via monitoring the evolution of the mitochondrial volume.

关键词： mitochondria morphology fission fusion dynamics modeling

Structural Adjustment of Oasis Agriculture in Xinjiang

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Chinese Journal of Population,resources and Environment 2005年第3期3卷 29-33页

作者： Lei Jun1,2.& Zhang Xiaolei1 1 Xinjiang institute of Ecology and Geography, Chinese academy of {2.,Urumqi 83.011,{3. 2.institute of Geography Science and natural resources research, Chinese academy of {2., beijing 100101.{3. Xinjiang institute of Ecology and Geography Chinese Academy of Sciences Urumqi 830011 China institute of Geography Science and natural {2. {3. Chinese Academy of Sciences Beijing 100101 China

Xinjiang’s oasis agriculture has made enormous strides over past decades. Structural adjustment of oasis agriculture sector has promoted production diversification. Xinjiang’s oasis agriculture sector is entering a new era. The era means more adjustments in oasis agricultural and rural economic structure so as to realize the sustainable development of agriculture. By summing and analyzing the main problems in Xinjinag’s oasis agricultural structure, such as raising farmer’s income, industry structure within agriculture, rural urbanization, pressure coming from market, agricultural environment degradation, puts forward the thinking, director and countermeasures to adjust oasis agricultural structure.

关键词： oasis agriculture structural adjustment agricultural industrialization Xinjiang

Review on the study of entanglement in quantum computation speedup

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Chinese Science Bulletin 2007年第16期52卷 2161-2166页

作者： DING ShengChao1,3.& JIN Zhi1,2.1 institute of Computing Technology,Chinese {2. of sciences,{3. 100080,china 2.{2. of Mathematics and Systems Science,Chinese {2. of sciences,{3. 100080,china 3.Graduate University of Chinese {2. of sciences,{3. 100080,china institute of Computing Technology Chinese Academy of Sciences Beijing China Graduate University of Chinese academy of sciences Beijing China academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing China

The role the quantum entanglement plays in quantum computation speedup has been widely disputed. Some believe that quantum computation's speedup over classical computation is impossible if entan-glement is absent,while others claim that the presence of entanglement is not a necessary condition for some quantum algorithms. This paper discusses this problem systematically. Simulating quantum computation with classical resources is analyzed and entanglement in known algorithms is reviewed. It is concluded that the presence of entanglement is a necessary but not sufficient condition in the pure state or pseudo-pure state quantum computation speedup. The case with the mixed state remains open. Further work on quantum computation will benefit from the presented results.

关键词：量子论量子纠缠量子计算加速模拟

Forcing mechanism of the Pleistocene east Asian monsoon variations in a phase perspective

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Science china Earth sciences 2005年第10期48卷 1708-1717页

作者： TIAN Jun1,2. WANG Pinxian1, CHENG Xinrong1, WANG Rujian1 & SUN Xiangjun1,3.1. State Key Laboratory of Marine Geology, Tongji University, Shanghai 2.0092. china 2. {2. of Geology and Geophysics, Chinese academy of {3., beijing 10002., china 3. {2. of Botany, Chinese academy of {3., beijing 100093. china Tongji University Chinese academy of sciences

The deep sea records from the ODP Sites 1143.and 1144 in the northern and southern South china Sea (SCS), including foraminiferal δ 18O and δ 13., Opal% and pollen percentage, reveal that the variations of the east Asian monsoon have been closely correlated with the variations of the Earth’s orbital parameters (eccentricity, obliquity and precession) and the global ice volume on orbital scale. All the monsoonal proxies show strong 100 ka, 41 ka and 2.0}ka cycles. Although G. ruber δ 13. of Site 1143.is coherent with the ETP (ETP= normalized (eccentricity + obliquity-precession) at eccentricity, obliquity and precession bands, most of the coherent relationship focuses on the precession band, and the other monsoonal proxies are coherent with the ETP only at the precession band, which indicate that precession dominates the Pleistocene tropical climate changes. The phase relationship of the monsoonal proxies with the foraminiferal δ 18O implies that the global ice volume changes have played a significant role in modulating the east Asian monsoon climate, at least dominating the winter monsoon. This forcing mechanism of the east Asian monsoon is apparently different from that of the Indian ocean mon-soon. The variations of the east Asian monsoon at the precession band, at least that of the winter monsoon, have been controlled not only by the sensible heating but also by the latent heating of the surface water in the South china Sea.

关键词： South china Sea, ODP, east Asian monsoon, orbital forcing, global ice volume.

Prediction method for October 2.03.solar storm

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Science china(Technological sciences) 2006年第5期49卷 629-640页

作者： XIE Yanqiong1, 2. 3. WEI Fengsi1, FENG Xueshang1 & ZHONG Dingkun1, 2.1. State Key Laboratory of Space Weather, Center for Space Science and Applied research, Chinese {2. of sciences, {3. 100080, china 2. Graduate School, Chinese {2. of sciences, {3. 10003., china 3. {12. of Meteorology, PLA University of Science and Technology, Nanjing 2.1101, china State Key Laboratory of Space Weather Center for Space Science and Applied Research Chinese Academy of Sciences Beijing China Graduate School Chinese Academy of Sciences Beijing China institute of Meteorology PLA University of Science and Technology Nanjing China

Aiming at two intense shock events on October 2. and 2., 2.03. this paper presents a two-step method, which combines synoptic analysis of space weather ——“observing” and quantitative prediction ——“palpating”, and then uses it to test predictions. In the first step of “observing”, on the basis of observations of the solar source surface magnetic field, interplanetary scintillation (IPS) and ACE spacecraft, we find that the propagation of the shocks is asymmetric relative to the normal direction of their solar sources, and the Earth is located near the direction of the fastest speed and the greatest energy of the shocks. As the two fast ejection shock events, the fast explosion of coronal mass of the extremely high temperature, the strong magnetic field, and the high speed background solar wind are also helpful to their rapid propagation. In the second step of “palpating”, we adopt a new membership function of the fast shock events for the ISF method. The predicted results show that for the onset time of the geomagnetic disturbance, the relative errors between the observational and the predicted results are 1.8% and 6.7%; and for the magnetic disturbance magnitude, the relative errors are 4.1% and 3.1%, re- spectively. Furthermore, the comparison among the predicted results of our two-step method with those of five other prevailing methods shows that the two-step method is advantageous. The results tell us that understanding the physical features of shock propagation thoroughly is of great importance in improving the prediction precision.

关键词： solar storm, interplanetary shock, interplanetary scintillation, two-step method, ISF method.

Indoor imitation experimental study on driving factors of rainfall-runoff process

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Science china Earth sciences 2005年第3期48卷 417-428页

作者： ZHANG Shifeng1, LIU Changming 1, XIA Jun1, TAN Ge 1, LI Lin1, LIU Caitang1, ZHOU Changqing 1 & GUO Lei2.1. institute of Geographic sciences and {2. {3. research, Chinese academy of sciences, beijing 100101, china 2. College of Water {3. and Hydropower Engineering, Wuhan University, Wuhan 43.072. china institute of Geographic sciences and {2. {3. research Chinese Academy of Sciences Beijing China College of Water resources and Hydropower Engineering Wuhan University Wuhan China

The driving actions of rainfall-runoff process can be attributed to two aspects. The first is the influence of precipitation process, and the second is that of the ground pad. The re- search results of 179 indoor experiments conducted to imitate rainfall-runoff process indicate that both precipitation duration and intensity play important roles in affecting confluence lag time, which is obviously inconsistent with the traditional hypotheses. The nonlinear relationship is of great significance to the confluence curve especially when the precipitation duration is less than the total confluence time or the precipitation intensity is small. Therefore it can be concluded that the unit hydrograph (UH) can be applied to rainfall-runoff process imitation in the humid areas in the south china region. However, the UH application should be strictly modified in accordance with precipitation conditions in the arid and semiarid region of north china where the precipitation duration is short and the intensity is unstable. It will be hard to get ideal imitation results if the UH is applied blindly without considering specific conditions in the north china region. This also explains the unsatisfactory imitation results caused by using various hydrological models in the north china region. When the precipitation duration is short, and the watershed has not reached total watershed concentration, the characteristics of confluence change greatly, which reflects the actual situation in the north china region. Therefore necessary nonlinear corrections should be made when UH is applied. If the duration is longer than the total confluence time and the balance between pondage and discharge is stricken, the imitation research results will be applicable to both rainfall-runoff relation with longer duration in the south china region and the basic theoreti- cal research on runoff generation and concentration. On conditions of adequate rainfall, peak discharge is in linear relationship with inten

关键词： rainfall-runoff, driving factors, indoor imitation, experiment.

Water Security Problem in North china: research and Perspective

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Pedosphere 2005年第5期15卷 563-575页

作者： XIA Jun LIU Meng-Yu JIA Shao-Feng Key Laboratory of Water Cycle ＆Related Land Surface Processes Institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 （China） State Key Laboratory of Water resources ＆ Hydropower Engineering sciences Wuhan University Wuhan 430072（China） Center for Agricultural resources research Institute of Genetic and Developmental Biology Chinese Academy of Sciences Shijiazhuang 050021 （China）

This paper addresses the emergence of water security problems in North china with the aim of highlighting key waterresources management and water security issues for the long-term development of North china. Three key problemsrelated to water resources and security issues in North china in the 2.st century are addressed, namely 1) the watercycle under environmental change, 2. agricultural water saving, and 3. water security. Development of internationalresearch related to these issues is also reviewed. The research plan developed recently by the Chinese academy of sciences(CAS) is discussed and suggestions on research and development of water resources science in North china are *** to focus on experimental catchments and dedicated research stations, a detailed knowledge of the water cycle onNorth china farmland has been compiled. A range of techniques that include isotope tracers has been used to acquirehydrologic data. Much research has been devoted to developing distributed hydrological models at different scales. In thewell irrigation district, five different water saving irrigation regimes have been investigated, and these regimes have hadwidespread application, and reduced water use 60-150 mm while they increased water use efficiency (WUE) by 2.%-3.%.Furthermore, preventing water pollution is the most essential step to ensure North china’s water security.

关键词： environmental change North china water cycle water resources water security

Accurate Quantification of Grassland Cover Density in an Alpine Meadow Soil Based on Remote Sensing and GPS

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Pedosphere 2005年第6期15卷 778-783页

作者： LIU Yan-Sui HU Ye-Cui PENG Liu-Ying institute of Geographic sciences and {2. {3. research Chinese Academy of Sciences Beijing 100101 （China） Graduate School of Chinese academy of sciences Beijing 100039 （China）

The principles of remotely estimating grassland cover density in an alpine meadow soil from space lie in the synchronous collection of in situ samples with the satellite pass and statistically linking these cover densities to their image properties according to their geographic coordinates. The principles and procedures for quantifying grassland cover density from satellite image data were presented with an example from Qinghai Lake, china demonstrating how quantification could be made more accurate through the integrated use of remote sensing and global positioning systems (GPS). An empirical model was applied to an entire satellite image to convert pixel values into ground cover density. Satellite data based on 68 field samples was used to produce a map of ten cover densities. After calibration a strong linear regression relationship (r2.= 0.745) between pixel values on the satellite image and in situ measured grassland cover density was established with an 89% accuracy level. However, to minimize positional uncertainty of field samples, integrated use of hyperspatial satellite data and GPS could be utilized. This integration could reduce disparity in ground and space sampling intervals, and improve future quantification accuracy even more.

关键词： alpine meadow soil grassland cover density quantitative remote sensing Qinghai Lake

Problems and countermeasures of sustainable development in Fujian Province in the new century

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Journal of geographical sciences 2000年第4期10卷 20-27页

作者： ZHOU Guo-min, MAO Han-ying, YANG Yan-feng (institute of Geographic sciences and {2. {3. research, Chinese academy of sciences, beijing 100101, china) 中科院地理科学与资源所北京

Fujian province is one of the coastal provinces with rapid economic growth after the reform and opening to the outside world. Being one of the two basic strategies of china in the new era, sustainable development plays a directive role in the coordinated development of socio-economy, natural {2. and ecology of Fujian. This paper analyses some important issues influencing sustainable development in Fujian in the next 2. years, such as the sustainable development of economy, investment environment improving and further opening to the outside, urbanization and coordinated development of city system, rational exploitation of natural {2., environmental conservation and ecological rehabilitation, and narrowing intraprovincial gap. Corresponding countermeasures are put forward.

关键词： Fujian province sustainable development problems and countermeasures