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A STUDY ON DESERTIFICATION OF WEST JIliN PROVINCE BASED ON REMOTE SENSING AND GIS TECHNIQUES

Chinese Geographical Science 2002年第1期12卷 73-79页

作者： zhu jin hua, li jin song(Changchun Institute of Geography, the Chinese Academy of Sciences, Changchun 130021, P.R. China) Changchun Institute of Geography the Chinese Academy of Sciences Changchun P. R. China

'West Jilin Province' in this paper means Zhenlai, Baicheng, Taonan, Da'an,Tongyu, Fuyu, songyuan, Qian'an, Changling, also includes Gongzhuling, Shuangliao, lishu, Siping andNong' an which have been suffered from desertification. In west Jilin Province there are three sandzones passing through, they are Xiang (Xianghai) -Wu (Ulan Tug) sand zone, Hai-Feng sand zone, andTao'er River right bank sand zone. The desertification area of west Jilin Province is 819 100 ha,making up 12. 5% of the total land area. Among desertification types, in Jilin Province lightdesertification is the major, then is medium decertification, hevey desertification is the *** to the comparison of the interpretation results of the Landsat images of the 1980s and the1990s by remote sensing and GIS techniques, it can be seen that the desertification area in westJilin Province basically didn't change on the whole, only increased 6130 ha, making up 0. 8% of thedesertification area, change scale is less than 1%. Evidently, desertification is controlled mostly,but some areas are continuing deterioration. The desertification process of China can be dividedinto three types according to origin nature, they are sandy steppe desertification, fixed sandarea(sand land) activation and dunes transfer invasion. Reasons of desertification of West JilinProvince are analyzed, they include natural factors (such as material source factors, chimatefactors) and artificial factors (such as destroying grass to reclaim, steppe decreasing greatly,illegally feeling shelter forest stands, constructing reservoir to influence eco-environment etc. ).Some suggestions are put forward as follows: establishing the social project for ecologicalreconstruction of degenerated land; intensifying planning and management of land use, revertingfarmland into forestland or pasture in a planned way. The key desertification control is to dependmainly on policy and management, then control techniques.

关键词： remote sensing (RS) and GIS techniques desertification west jilin province

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Effect of order–disorder transition on thermodynamic and electronic properties of σ and χ phases in W–Re alloy: the first-principles calculation

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Tungsten 2025年第1期7卷 195-213页

作者： Zhi-Peng zhu Dian Jia William Yi Wang Jun-Lei Yin Xing-Yu Gao Shu-Feng Yang Hai-Feng song jin-Shan li State Key Laboratory of Solidification Processing Northwestern Polytechnical University Laboratory of Computational Physics Institute of Applied Physics and Computational Mathematics School of Metallurgical and Ecological Engineering University of Science and Technology Beijing

The Tungsten-Rhenium(W-Re) alloys,celebrated for their high melting point,strength at elevated temperatures,electrical resistivity,and radiation resistance,have been widely utilized in high-temperature components,aerospace,electronics,and nuclear *** constituents of the topologically close-packed(TCP) phases,the sigma phase(σ) and chi phase(χ) formed within W-Re alloys wield considerable influence on the mechanical properties and the stability of the *** calculations were utilized in the present work to explore the structural,thermodynamic,and electronic properties of both ordered and disordered configurations within the σ and χ phases,culminating in a systematic elucidation of the higher phase stability exhibited by the ordered *** is found that the bulk modulus of these two phases is directly proportional to the concentration of Re in the alloy,while the equilibrium volume is inversely *** thermodynamic parameters of the σ and χ phases are calculated via the mean-field potential *** similar trends observed in the isobaric heat capacity,enthalpy increment,and entropy change curves for these two phases suggest they possess comparable thermodynamic *** is noteworthy that the contribution of ionic vibrations predominantly affects the isobaric heat capacity,while the contribution of thermal electronic excitations increases linearly with *** the structure and thermodynamic properties of TCP phases in W-Re alloys at low temperatures has profound significance for optimizing material performance,microstructures features,establishing theoretical foundations,and predicting material behavior.

关键词： First-principles calculations Phase stability TCP phases Thermodynamic properties W–Re alloy

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Domain generalization with semi-supervised learning for people-centric activity recognition

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Science China(Information Sciences) 2025年第1期68卷 171-188页

作者： jing liU Wei zhu Di li Xing HU liang song Academy for Engineering & Technology Fudan University Shanghai East-bund Research Institute on Networking Systems of AI School of Optoelectronic Information and Computer Engineering University of Shanghai for Science & Technology

People-centric activity recognition is one of the most critical technologies in a wide range of real-world applications,including intelligent transportation systems, healthcare services, and brain-computer interfaces. Large-scale data collection and annotation make the application of machine learning algorithms prohibitively expensive when adapting to new tasks. One way of circumventing this limitation is to train the model in a semi-supervised learning manner that utilizes a percentage of unlabeled data to reduce the labeling burden in prediction tasks. Despite their appeal, these models often assume that labeled and unlabeled data come from similar distributions, which leads to the domain shift problem caused by the presence of distribution gaps. To address these limitations, we propose herein a novel method for people-centric activity recognition,called domain generalization with semi-supervised learning(DGSSL), that effectively enhances the representation learning and domain alignment capabilities of a model. We first design a new autoregressive discriminator for adversarial training between unlabeled and labeled source domains, extracting domain-specific features to reduce the distribution gaps. Second, we introduce two reconstruction tasks to capture the task-specific features to avoid losing information related to representation learning while maintaining task-specific consistency. Finally, benefiting from the collaborative optimization of these two tasks, the model can accurately predict both the domain and category labels of the source domains for the classification task. We conduct extensive experiments on three real-world sensing datasets. The experimental results show that DGSSL surpasses the three state-of-the-art methods with better performance and generalization.

关键词： activity recognition deep learning domain generalization semi-supervised learning adversarial training

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Combined anisotropic and cyclic constitutive model for laser powder bed fusion fabricated aluminum alloy

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Chinese Journal of Aeronautics 2025年第1期38卷 165-184页

作者： Fei-Fan li Jihong zhu Weihong ZHANG Shifeng WEN jingwen song Jun MA Gang FANG State IJR Center of Aerospace Design and Additive Manufacturing School of Mechanical EngineeringNorthwestern Polytechnical UniversityXi’an 710072China Research&Development Institute of Northwestern Polytechnical University in Shenzhen Shenzhen 518063China School of Materials Science and Engineering Northwestern Polytechnical UniversityXi'an 710072China Department of Mechanical and Industrial Engineering Norwegian University of Science and TechnologyTrondheim 7491Norway State Key Laboratory of Tribology in Advanced Equipment Department of Mechanical EngineeringTsinghua UniversityBeijing 100084China

This study presents new methods to effectively model the anisotropic yielding and hardening behavior of laser powder bed fusion fabricated aluminum alloy under both monotonic and cyclic loading *** proposed model combines the yield surface-interpolation method to accurately describe the anisotropic hardening rates in various directions,with the Chaboche kinematic hardening rule to precisely reflect the cyclic *** numerical implementation of the combined anisotropic and cyclic constitutive model,a fully implicit stress integration algorithm based on return mapping method is ***,the multiple parameters associated with the model are categorized and identified in an uncoupled *** isotropic and cyclic hardening parameters are determined by an inverse method,and the stability of the optimization outcomes is validated by applying different starting points for the ***,the back-stress effect on the identification of anisotropic parameters associated with the stress invariant-based Hill48 yield function is considered for the first *** consideration leads to an improved prediction accuracy compared to the identification of anisotropic parameters without considering back-stress *** combined anisotropic and cyclic constitutive model,along with the calibrated parameters,are proven capable of accurately reproducing the intricate deformation behavior of laser powder bed fusion fabricated AlSi10Mg.

关键词： Constitutive models Anisotropy Kinematic hardening Laser powder bed fusion Aluminum alloys

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DNA walker induced “signal on” fluorescence aptasensor strategy for rapid and sensitive detection of extracellular vesicles in gastric cancer

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Chinese Chemical Letters 2025年第2期36卷 328-331页

作者： Gaojian Yang Zhiyang li Rabia Usman zhu Chen Yuan liu song li Hui Chen Yan Deng Yile Fang Nongyue He State Key Laboratory of Digital Medical Engineering School of Biological Science and Medical Engineering Southeast University Department of Clinical Laboratory the Affiliated Drum Tower Hospital of Nanjing University Medical School Hunan Key Laboratory of Biomedical Nanomaterials and Devices Hunan University of Technology Institute of Cytology and Genetics School of Basic Medical Sciences Hengyang Medical School University of South China Institute for Future Sciences University of South China

The extracellular vesicles show great potential as a noninvasive biomarker for the early detection of cancer. Hence, there is an urgent requirement to create biosensors that are time-saving, simple, and easily scalable in order to accomplish rapid, sensitive, and quantitative detection of extracellular vesicles. In this study, we present a self-propelled DNA walker powered by endonuclease *** CI, which enables the development of a “signal on” sensing platform for the rapid and highly sensitive detection of extracellular vesicles. The DNA motor employed tracks made of streptavidin magnetic beads, which consisted of substrate strands labeled with fluorescein and motor strands locked by aptamers. The aptamer recognition of the target protein on extracellular vesicles unlocked the motor strand, initiating the DNA motor process. After replacing the optimal buffer solution containing the endonuclease *** I, the motor strands autonomously moved along the streptavidin magnetic beads track, continuously releasing fluorescent molecules and producing detectable fluorescence signals. Under optimal conditions, the detection range was from 2×10～4particles/mL to 2×10～9particles/mL, with a detection limit of 2.9×10～3particles/mL,demonstrating excellent selectivity. This method has demonstrated good selectivity in different tumorderived extracellular vesicles and performs well in complex biological samples. The ability to effectively analyze surface proteins of extracellular vesicles in a short period of time gives our DNA walker a tremendous potential for developing simple and cost-effective clinical diagnostic devices.

关键词： Aptamer Detection Extracellular vesicles Nt.BbvCI Streptavidin magnetic beads

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Impacts of the annual cycle of background SST in the tropical Pacific on the phase and amplitude of ENSO

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Atmospheric and Oceanic Science Letters 2025年第1期18卷 12-17页

作者： song Jiang Congwen zhu Ning Jiang State Key Laboratory of Severe Weather(LASW) Chinese Academy of Meteorological SciencesBeijingChina College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijingChina

The dominant annual cycle of sea surface temperature(SST)in the tropical Pacific exhibits an antisymmetric mode,which explains 83.4%total variance,and serves as a background of El Niño-Southern Oscillation(ENSO).However,there is no consensus yet on its anomalous impacts on the phase and amplitude of *** on data during 1982-2022,results show that anomalies of the antisymmetric mode can affect the evolution of ENSO on the interannual scale via Bjerknes feedback,in which the positive(negative)phase of the antisymmetric mode can strengthen El Niño(La Niña)in boreal winter via an earlier(delayed)seasonal cycle transition and larger(smaller)annual *** magnitude of the SST anomalies in the equatorial eastern Pacific can reach more than±0.3◦C,regulated by the changes in the antisymmetric mode based on random sensitivity *** reveal the spatial pattern of the annual cycle associated with the seasonal phase-locking of ENSO evolution and provide new insight into the impact of the annual cycle of background SST on ENSO,which possibly carries important implications for forecasting ENSO.

关键词： Annual cycle SST anomaly Antisymmetric mode ENSO

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Palindrome-mediated DNA nanotubes with cell-specific aptamers to improve targeted antitumor effects and reduce toxicity on non-small cell lung cancer

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Science China(life Sciences) 2025年第2期68卷 454-466页

作者： Cheng Zheng Lanlan song Chang Yu lingye zhu jing Zhang Ning Wang Mengchu liu Shini li liangxing Wang Zhifa Shen Xiaoying huang Division of Pulmonary Medicine the First Affiliated Hospital of Wenzhou Medical UniversityKey Laboratory of Interdiscipline and Translational MedicineWenzhou 325000China Intervention Department the First Affiliated Hospital of Wenzhou Medical UniversityWenzhou 325000China Key Laboratory of Laboratory Medicine Ministry of Education of Chinaand Zhejiang Provincial Key Laboratory of Medical GeneticsSchool of Laboratory Medicine and Life SciencesWenzhou Medical UniversityWenzhou 325035China

Chemotherapy is regarded as a widely used and effective treatment strategy for lung cancer,although most conventional chemotherapeutics cause severe toxic side-effects due to their indiscriminate attacks on both cancerous and normal *** nucleic acid nanomaterials are emerging as a promising drug delivery strategy,their clinical applications are limited by rapid degradation by nucleases and difficulties in targeting cancer *** this study,we have developed a Rhein-loaded aptamer-based DNA nanotube(DNT-S6@Rhein)for the targeted and efficient therapy of non-small cell lung *** the palindrome segments,two specified oligonucleotides were hybridized and folded into the well-defined nanotubes(DNT-S6),with the S6 aptamer distributed *** obtained nanotubes exhibited excellent serum stability and targeting ability towards A549 cells due to the firm structure and decoration of the S6 ***,as an antitumor drug and DNA intercalator,can be effectively inserted into the *** drug-loaded nanotubes rapidly disassembled in intracellular environment and then the released Rhein was found to activate cellular apoptotic process and significantly suppress proliferation,migration and invasion of A549 ***,DNT-S6@Rhein could efficiently accumulate in tumor regions,offering compelling therapeutic efficacy and biocompatibility under both in vitro and in vivo *** findings of this study provide a promising strategy for mitigating the inevitable systemic side-effects of chemotherapy and expand the potential application of DNA nanostructure on targeted drug delivery.

关键词： DNA nanotube self-assembly Rhein targeted drug delivery cancer therapy

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Mechanistic insight on nanomaterial-induced reactive oxygen species formation

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Journal of Environmental Sciences 2025年第5期151卷 200-210页

作者： Jianzhong Cao Qingchun Wu Xuting liu Xiangyu zhu Chunfeng huang Xinyu Wang Yang song State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China University of Chinese Academy of Sciences Beijing 100049China

Reactive oxygen species(ROS)are closely related to cell death,proliferation and ***,excessive ROS levels may exceed the cellular oxidative capacity and cause irreversible *** are often inadvertently exposed to nanomaterials(NMs).Therefore,elucidating the specific routes of ROS generation induced by NMs is crucial for comprehending the toxicity mechanisms of NMs and regulating their potential *** paper provides a comprehensive review of the toxicity mechanisms and applications of NMs from three perspectives:(1)Organelle *** the impact of NMmediated ROS onmitochondria,unravelingmechanisms at the organelle level.(2)NMs’*** the broad applications and biosafety considerations of Nanozymes,a unique class of NMs.(3)Cellular *** the toxic effects and mechanisms of NMs in cells at a holistic cellular *** on these perspectives,the paper scrutinizes the regulation of Fenton reactions by NMs in ***,it introduces diseases resulting fromNM-mediated ROS at the organism *** comprehensive review aims to provide valuable insights for studying NM-mediated mechanisms at both cellular and organism levels,offering considerations for the safe design of nanomaterials.

关键词： Nanomaterials Reactive oxygen species(ROS) Toxicity Mitochondria Oxidative stress

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Hierarchical porous carbon guided by constructing organic-inorganic interpenetrating polymer networks to facilitate performance of zinc hybrid supercapacitors

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Chinese Chemical Letters 2025年第1期36卷 561-567页

作者： Ting Shi Ziyang song Yaokang Lv Dazhang zhu ling Miao lihua Gan Mingxian liu Shanghai Key Lab of Chemical Assessment and Sustainability School of Chemical Science and EngineeringTongji UniversityShanghai 200092China College of Chemical Engineering Zhejiang University of TechnologyHangzhou 310014China

Customized design of well-defined cathode structures with abundant adsorption sites and rapid diffusion dynamics,holds great promise in filling capacity gap of carbonaceous cathodes towards high-performance Zn-ion hybrid supercapacitors(ZHC).Herein,we fabricate a series of dynamics-oriented hierarchical porous carbons derived from the unique organic-inorganic interpenetrating polymer *** interpenetrating polymer networks are obtained through physically knitting polyferric chloride(PFC)network into the highly crosslinked resorcinol-formaldehyde(RF)*** of covalent bonding,physical interpenetrating force in such RF-PFC networks efficiently relieves the RF skeleton shrinkage upon ***,the in-situ PFC network sacrifices as a structure-directing agent to suppress the macrophase separation,and correspondingly 3D hierarchical porous structure with plentiful ion-diffusion channels(pore volume of 1.35 cm^(3)/g)is generated in the representative HPC_(4) via nanospace occupation and swelling *** removal of Fe fillers leaves behind a large accessible specific surface area of 1550 m^(2)/g for enhanced Zn-ion *** used as the cathode for ZHC,HPC_(4) demonstrates a remarkable electrochemical performance with a specific capacity of 215.1 mAh/g at 0.5 A/g and a high Zn^(2+)ion diffusion coefficient of 11.1×10^(-18)cm^(2)/*** ZHC device yields 117.0 Wh/kg energy output at a power density of 272.1 W/kg,coupled with good cycle lifespan(100,000 cycles@10 A/g).This work inspires innovative insights to accelerate Zn diffusion dynamics by structure elaboration towards high-capacity cathode materials.

关键词： Carbonaceous cathode Interpenetrating polymer networks Zinc-ion hybrid supercapacitors Specific capacity Energy/power density

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China's Yangtze River drought: A cascade of impacts from mountains to sea

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Science China Earth Sciences 2025年第3期68卷 957-962页

作者： Nan JIA Jie CHENG Yinshuai li lilin ZHENG Wen song Ruishan CHEN Annah zhu Center for Systems Integration and Sustainability Part of College of Agriculture and Natural Resources Michigan State University School of Design Shanghai Jiao Tong University School of Geographic Sciences East China Normal University Wageningen University

1. Introduction With record heatwaves and low precipitation, in 2022 the Yangtze River basin experienced its most severe drought since 1961(Lyu et al., 2023). Meanwhile, it also hosted the most severe heatwave recorde...

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