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Calculation of Ecological Footprint Based on Modified Method and Quantitative Analysis of Its Impact Factors——A Case Study of Shanghai

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Chinese Geographical Science 2006年第4期16卷 306-313页

作者： gao Chengkang JIANG Dahe WANG dan YAN Jonathan College of Environmental Science and Engineering Tongji University Shanghai 200092 China Department of Geography Shanghai Normal University Shanghai 200234 China Department of Pacific and International Affairs University of California San Diego USA

Ecological footprint （EF） has attracted much attention internationally as a potential indicator for sustainable development. In China, EF has also gained recognition in related fields and disciplines. Moreover, some scholars in these fields have proposed alternative methods to calculate EF and have made some progress. This paper, therefore, begins with the introduction and development of EF in China. However, the established methods of EF calculation hold some limitations, such as indicator variance and result abnormality. In order to resolve those problems, the authors make a further modification considering the demand of EF as a comprehensive indicator： 1） More accurate analysis has been done to divide EF into several parts： imported EF, exported EF, and producible EF, which is the solution to the problem of abnormality in original EF results and can explain abnormal phenomena reasonably. 2） Considering the actual situa- tion of Shanghai, emended equivalence factor is brought forward and a matrix is formed with equivalence factors. The measure can reduce the deviation between the fact and the results. 3） The calculation compares local yield with global average yield to analyze the effects of yields. And based on local yields in different years, the results are more accurate. Finally, the calculation method is applied to calculating EF of Shanghai from 1980 to 2003, and the subsequent detailed analysis is presented. Available data and results suggest a statistically significant correlation coefficient between EF and GDP, population density and urbaniTation level. Through analyzing the process of calculating EF and its results, it can be seen that EF, as a macro-indicator, can not exactly indicate whether development within a region can meet the re- quests of sustainable development, which can be explained by the fact that the result of EF is impacted greatly by sub- jective factors including national policy,available technology, population, etc. Nevertheless, EF ca

关键词： ecological footprint quantitative analysis impact factors Shanghai

Plant phylogenomics based on genome-partitioning strategies:Progress and prospects

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Plant Diversity 2018年第4期40卷 158-164页

作者： Xiangqin Yu dan Yang Cen Guo Lianming gao Key Laboratory for Plant Diversity and Biogeography of East Asia Kunming Institute of Botany Chinese Academy of Sciences Kunming College of Life Science University of Chinese Academy of Sciences Germplasm Bank of Wild Species Kunming Institute of Botany Chinese Academy of Sciences

The rapid expansion of next-generation sequencing （NGS） has generated a powerful array of approaches to address fundamental questions in biology. Several genome-partitioning strategies to sequence selected subsets of the genome have emerged in the fields of phylogenomics and evolutionary genomics. In this review, we summarize the applications, advantages and limitations of four NGS-based genome- partitioning approaches in plant phylogenomics： genome skimming, transcriptome sequencing （RNA- seq）, restriction site associated DNA sequencing （RAD-Seq）, and targeted capture （Hyb-seq）. Of these four genome-partitioning approaches, targeted capture （especially Hyb-seq） shows the greatest promise for plant phy^ogenetics over the next fex~ years. This reviex~ wi~ aid ~esea^chers in their selection of appropriate genome-partitioning approaches to address questions of evolutionary scale, where we anticipate continued development and expansion ofwhole-genome sequencing strategies in the fields of plant phylogenomics and evolutionary biology research.

关键词： Plant phylogenomics Next-generation sequencing Whole-genome sequencing Genome skimming RAD-Seq Targeted capture

Use of calcein and alizarin red S for immersion marking of black rockfish Sebastes schlegelii juveniles

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Chinese Journal of Oceanology and Limnology 2014年第1期32卷 88-98页

作者： Lü Hongjian ZHANG Xiumei XI dan gao Tianxiang College of Fisheries Ocean University of China College of Animal Science and Technology Southwest University

Black rockfish Sebastes schlegelii juveniles （30-40 mm total length） were immersed in a range of calcein （CAL） solutions at concentrations ranging from 50 to 250 mg/L and alizarin red S （ARS） solutions at concentrations ranging from 100 to 500 mg/L in filtered seawater （salinity 30） for 24 h. Fluorescent marks were detected in otoliths （sagittae, asteriscus）, scales, fin rays （dorsal, pectoral, ventral, anal, and caudal fin rays）, and fin spines （dorsal, ventral, and anal fin spines） after a 60-d growth experiment. With the exception of 50-100 rng/L CAL, acceptable marks were produced in the otoliths and fin spines by all concentrations of CAL and ARS. In particular, marks were clearly visible under normal light in the sagittae, asteriscus, and fin spines offish immersed in 200 500 mg/L, 300-500 rag/L, and 200-500 mg/LARS, respectively. Scales and fin rays had acceptable marks at much higher concentrations （≥50 mg/L CAL, ≥300 mg/L ARS for scales and ≥50 mg/L CAL,≥200 mg/L ARS for fin rays）. The mark quality was highest （i.e., acceptable marks were observed in all sampled structures after immersion marking） in fish immersed in 150-250 mg/L CAL or 300-500 mg/LARS. In addition, there was no significant difference in survival and growth of marked fish compared with controls 60 d post-marking （P〉0.05）.

关键词： Sebastes schlegelii calcein (CAL) alizarin red S (ARS) otoliths fin rays fin spines

Fano Resonance Effect in CO-Adsorbed Zigzag Graphene Nanoribbons

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Chinese Physics Letters 2017年第9期34卷 91-94页

作者： gao Wang Meng-Qiu Long dan Zhang Advanced Research Center Central South University Changsha 410083 Institute of Super Microstructure and Ultrafast Process Central South University Changsha 410083 School of Science Hunan University of Technology Zhuzhou 412007

Quantum interference plays an important role in tuning the transport property of nano-devices. Using the non- equilibrium Green＇s Function method in combination with density functional theory, we investigate the influence to the transport property of a CO molecule adsorbed on one edge of a zigzag graphene nanoribbon device. Our results show that the CO molecule-adsorbed zigzag graphene nanoribbon devices can exhibit the Fano resonance phenomenon. Moreover, the distance between CO molecules and zigzag graphene nanoribbons is closely related to the energy sites of the Fano resonance. Our theoretical analyses indicate that the Fano resonance would be attributed to the interaction between CO molecules and the edge of the zigzag graphene nanoribbon device, which results in the localization of electrons and significantly changes the transmission spectrum.

关键词： DOS Fano Resonance Effect in CO-Adsorbed Zigzag Graphene Nanoribbons CO

Controlling the key by choosing the detection bits in quantum cryptographic protocols

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Science China(Information Sciences) 2015年第11期58卷 200-210页

作者： LIU Bin gao Fei HUANG Wei LI dan WEN QiaoYan State Key Laboratory of Networking and Switching Technology Beijing University of Posts and Telecommunications College of Computer Science Chongqing University

Eavesdropping detection is an indispensable process of most quantum cryptographic protocols. By publishing and comparing part of the shared bits, called as detection bits, the participants can check whether there exists an eavesdropper. Generally, the detection bits are chosen randomly. Consequently, the secret bits, i.e., the rest bits, are also random. Then, what if the detection bits are chosen non-randomly? Can the participant who chooses the detection bits make the secret bits to be a predetermined string he expected?This paper focuses on the participants’ key control capability when they choose the detection bits selectively in two-party quantum communication protocols. Concretely, we analyze the participants’ key control capability in different situations of different proportions of the detection bits. And we prove that the participants can predetermine, with high probability, any part of the secret bits of which the length is smaller than that of the detection bits. The above result has various potential applications in quantum cryptographic ***, utilizing this non-random selection of the detection bits, one can realize the function of a deterministic quantum key distribution protocol through a random one if the number of the detection bits is not smaller than that of the secret bits. What is more, we find that quite a few quantum key agreement protocols cannot guarantee the fairness of the key in the sense that the participant who chooses the detection bits can control the key somewhat.

关键词： eavesdropping detection deterministic quantum key distribution quantum key agreement quantum information quantum cryptography

Regional climate dynamical downscaling over the Tibetan Plateau——From quarter-degree to kilometer-scale

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Science China Earth Sciences 2022年第12期65卷 2237-2247页

作者： Yanhong gao Jianwei XU Meng ZHANG Zhaoyang LIU Jingyu dan Institute of Atmospheric Sciences&Department of Atmospheric and Oceanic Sciences Fudan UniversityShanghai 200438China Shanghai Frontiers Science Center of Atmosphere-Ocean Interaction Shanghai 200438China Natiobal Observations and Research Station for Wetland Ecosystems of the Yangtze Estuary Shanghai 200438China College of Resource and Environment Hunan University of Art and SciencesChangde 415000China

The Tibetan Plateau(TP)possesses the largest cryosphere in the world outside of the Arctic and Antarctic,and is the source of nine major rivers in *** surface environment of the TP has undergone significant changes against the background of global *** is projected that the continuation of climate change in the future will result in most of the glaciers and frozen soil disappearing by the end of this century,and freshwater resources will be greatly reduced,on which 22%of the world’s population *** environmental changes are of great concern to global society given the influences of the TP on the climate at the global ***,great uncertainties exist in global climate simulations over the TP,which affects our ability to properly understand the associated water security *** on atmospheric dynamics and physical processes,dynamical downscaling can characterize surface conditions more accurately than global simulations,and better simulate and predict regional or local weather and climate *** advances in supercomputing,the grid spacing of dynamical downscaling simulations has been continuously increasing,marching the technique into the kilometer-scale *** this paper,the origin and development of dynamical downscaling in the TP region from the quarter-degree to kilometer scale is firstly introduced,including an assessment of the advantages and disadvantages of dynamical downscaling at the kilometer scale over the ***,the main land surface factors affecting the performance of dynamical downscaling over the TP are described,as well as a brief introduction to a land surface model with specific plateau ***,it has emerged that perfecting the land surface model and improving the performance of land-atmosphere interaction are the most effective ways to advance the performance of dynamic downscaling in this ***,the challenges and some recommended future research directions are discussed and

关键词： Tibetan Plateau Climate dynamical downscaling Land surface processes

Safety-Critical Model-Free Control for Multi-Target Tracking of USVs with Collision Avoidance

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IEEE/CAA Journal of Automatica Sinica 2022年第7期9卷 1323-1326页

作者： Shengnan gao Zhouhua Peng Haoliang Wang Lu Liu dan Wang School of Marine Electrical Engineering Dalian Maritime UniversityDalian 116026China School of Marine Engineering Dalian Maritime UniversityDalian 116026China IEEE

Dear editor,This letter addresses the multi-target tracking of underactuated unmanned surface vehicles(USVs)subject to multiple stationary/moving *** kinetic model parameters of each USV are totally unknown.A safety-critical model-free control method is proposed for tracking multiple targets with a collision-free containment ***,a distributed containment extended state observer(DCESO)is designed to estimate the convex hull spanned by the multiple *** the kinematic level,a collision-free kinematic guidance law is presented using a control barrier function(CBF)and an extended state observer for each follower *** the kinetic level,a model-free position tracking control law by using an adaptive ESO(AESO)is presented for each follower *** the designed safety-critical model-free control method,cooperative tracking of multiple targets under multiple stationary/moving obstacles can be achieved using completely unknown kinetic model *** are provided to illustrate the efficacy of the proposed safety-critical model-free control method for a fleet of USVs.

关键词： stationary collision totally

State diagram of spin-torque oscillator with perpendicular reference layer and planar field generation layer

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Progress in Natural Science:Materials International 2015年第3期25卷 258-262页

作者： Mengwei Zhang Longze Wang dan Wei Kaizhong gao Key Lab of Advanced Materials School of Materials Science and EngineeringTsinghua University Advanced Technology Development Seagate Technology

The state diagram of spin-torque oscillator(STO) with perpendicular reference layer(REF) and planar field generation layer(FGL) was studied by a macrospin model and a micro-magnetic model. The state diagrams are calculated versus the current density, external field and external field angle. It was found that the oscillation in FGL could be controlled by current density combined with external field so as to achieve a wide frequency range. An optimized current and applied field region was given for microwave assisted magnetic recording(MAMR), considering both frequency and output field oscillation amplitude. The results of the macro-spin model were compared with those of the micro-magnetic model. The macro-spin model was qualitatively different from micro-magnetics and experimental results when the current density was large and the FGL was non-uniform.

关键词： Spin-torque oscillator Micromagnetic Macrospin External field MAMR

A microfluidic photolithography for controlled encapsulation of single cells inside hydrogel microstructures

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Science China Chemistry 2012年第4期55卷 494-501页

作者： JiangJiang Liu dan gao SiFeng Mao Jin-Ming Lin Tsinghua Univ Dept Chem Beijing Key Lab Microanalyt Methods & Instrumenta Beijing 100084 Peoples R China

A microfluidic approach to generate hydrogel microstructures inside microchannels for controlled encapsulation of single cells was developed. The method was based,on a modified microscope projection photolithography which allowed for the photopolymerization of poly（ethylene glycol） diacrylate （PEGDA） inside microchannels. Uniformsized hydrogel microstmctures （-50 pan in diameter） were generated one by one with determined positions to encapsulate single cells without losing the viability. Cells of interest could be identified by any kinds of visible labels to be selectively encapsulated inside the formed hydrogel microstructures. Large-scale encapsulation of single cells was achieved with a relatively high efficiency of 80% and the viability of encapsulated cells could be guaranteed by removing the dead cells identified with Trypan blue. This method is simple, fast and convenient to pattern the microchannels with single cells for a wide range of cell-based applications. For demonstration, two intracellular enzyme assays of carboxylesterase were performed to investigate the distribution of enzyme concentrations and the kinetic information within the encapsulated single HepG2 cells.

关键词： microfluidic single cells hydrogel microstructures HepG2 cells enzyme assay