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Journal of Arid Land 2014年第6期6卷 753-761页

作者： Lu GONG changjun li Tashpolat TIYIP College of Resources and Environment Science Xinjiang University Key Laboratory of Oasis Ecology Ministry of Education Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences Cele National Station of Observation & Research for Desert-Grassland Ecosystem in Xinjiang

How common reed （Phragmites australis Trin. ex Steud.） colonization correlates to soil heterogeneity and environmental determinants remains unclear in arid areas. We conducted a field investigation and soil sampling in 100 plots along Keriya River Basin to uncover the relationship between common reed and heterogeneous soils. Reed colonization variables and its soil properties were measured and recorded for the analysis of their relationship using Pearson correlation and redundancy analysis methods. The comparison results of common reed characteris- tics among 100 plots showed that common reeds performed strong tolerance and ecophysiological plasticity to edaphic stresses. Common reed colonization was tightly connected to soil heterogeneity according to the correla- tion analysis between its colonization characteristics and soil properties. Common reed colonization got feedbacks on soil properties as well, including the increase of soil organic matter and the alleviation of salt uplifting. The main limiting environmental determinant of common reed colonization was soil salt, followed by pH and soil water content.

关键词： soil heterogeneity plant colonization common reed plasticity determinant

A MODIFIED PRECONDITIONER FOR PARAMETERIZED INEXACT UZAWA METHOD FOR INDEFINITE SADDLE POINT PROBLEMS

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Journal of Computational Mathematics 2018年第4期36卷 579-590页

作者： Xinhui Shao Chen li Tie Zhang changjun li Department of Mathematics College of Science Northeastern University Shenyang 110819 China

The preconditioner for parameterized inexact Uzawa methods have been used to solve some indefinite saddle point problems. Firstly, we modify the preconditioner by making it more generalized, then we use theoretical analyses to show that the iteration method converges under certain conditions. Moreover, we discuss the optimal parameter and matrices based on these conditions. Finally, we propose two improved methods. Numerical experiments are provided to show the effectiveness of the modified preconditioner. All methods have fantastic convergence rates by choosing the optimal parameter and matrices.

关键词： Preconditioner Inexace Uzawa method Saddle point problems Ndefiniteness Convergence

Constructing central hollow cylindrical reduced graphene oxide foams with vertically and radially orientated porous channels for highly efficient solar-driven water evaporation and purification

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Nano Research 2023年第5期16卷 6343-6352页

作者： changjun li Wei li Hao-Yu Zhao Xin-Yue Feng Xiaofeng li Zhong-Zhen Yu State Key Laboratory of Organic-Inorganic Composites College of Materials Science and EngineeringBeijing University of Chemical TechnologyBeijing 100029China Beijing Key Laboratory of Advanced Functional Polymer Composites Beijing University of Chemical TechnologyBeijing 100029China College of Materials Science and Engineering Shandong University of Science and TechnologyQingdao 266590China

Although solar steam generation is an eco-friendly approach for desalinating seawater and purifying wastewater,there are still issues on how to improve the efficiency of solar energy utilization and accelerate the water and heat transport inside the solardriven water ***,we design a central hollow cylindrical reduced graphene oxide(RGO)foam with vertically and radially orientated channels as a solar steam generation device for efficient water evaporation and *** vertically aligned porous channels accelerate upward transport of water to the top evaporation surface,while the radially aligned porous channels facilitate water transport and heat transfer along the radial directions for fully utilizing the heat accumulated inside the central cylindrical hole of the *** central hole of the foam plays a highly positive role in accumulating more heat for accelerating the water evaporation,the newly generated inner sidewall resulted from the central hole can gain extra thermal energy from surrounding environment in the same way as the outer sidewall of the foam due to the surface cooling effect of the water *** a result,the vertically and radially aligned RGO foam evaporator with central hollow cylinder achieves a high solar steam generation rate of 2.32 kg·m^(−2)·h^(−1)with an exceptional energy conversion efficiency of 120.9%under 1-sun irradiation,superior to the vertically aligned RGO foam without the central hole(1.83 kg·m^(−2)·h^(−1),96.9%)because of the enhanced water and heat transfer inside the porous channels,the efficient utilization of environmental energy.

关键词： hollow cylindrical foams reduced graphene oxide solar steam generation water evaporation rate seawater desalination

Retrieve Sea Surface Salinity Using Principal Component Regression Model Based on SMOS Satellite Data

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Journal of Ocean University of China 2016年第3期15卷 399-406页

作者： ZHAO Hong li changjun li Hongping LV Kebo ZHAO Qinghui School of Mathematical Sciences Ocean University of China Department of Marine Technology College of Information Science and Engineering Ocean University of China

The sea surface salinity(SSS) is a key parameter in monitoring ocean states. Observing SSS can promote the understanding of global water cycle. This paper provides a new approach for retrieving sea surface salinity from Soil Moisture and Ocean Salinity(SMOS) satellite data. Based on the principal component regression(PCR) model, SSS can also be retrieved from the brightness temperature data of SMOS L2 measurements and Auxiliary data. 26 pair matchup data is used in model validation for the South China Sea(in the area of 4?–25?N, 105?–125?E). The RMSE value of PCR model retrieved SSS reaches 0.37 psu(practical salinity units) and the RMSE of SMOS SSS1 is 1.65 psu when compared with in-situ SSS. The corresponding Argo daily salinity data during April to June 2013 is also used in our validation with RMSE value 0.46 psu compared to 1.82 psu for daily averaged SMOS L2 products. This indicates that the PCR model is valid and may provide us with a good approach for retrieving SSS from SMOS satellite data.

关键词： sea surface salinity retrieved algorithm SMOS principle component regression

LRP6 in mesenchymal stem cells is required for bone formation during bone growth and bone remodeling

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Bone Research 2014年第1期2卷 43-54页

作者： changjun li Bart O Williams Xu Cao Mei Wan Department of Orthopaedic Surgery Johns Hopkins University School of Medicine Center for Skeletal Disease and Tumor Metastasis and Laboratory of Cell Signaling and Carcinogenesis Van Andel Research Institute

lipoprotein receptor-related protein 6 （LRP6） plays a critical role in skeletal development and homeostasis in adults. However, the role of LRP6 in mesenchymal stem cells （MSCs）, skeletal stem cells that give rise to osteoblastic lineage, is unknown. In this study, we generated mice lacking LRP6 expression specifically in nestin＋ MSCs by crossing nestin-Cre mice with LRP6 flox mice and investigated the functional changes of bone marrow MSCs and skeletal alterations. Mice with LRP6 deletion in nestin＋ cells demonstrated reductions in body weight and body length at I and 3 months of age. Bone architecture measured by microCT （uCT） showed a significant reduction in bone mass in both trabecular and cortical bone of homozygous and heterozygous LRP6 mutant mice. A dramatic reduction in the numbers of osteoblasts but much less significant reduction in the numbers of osteoclasts was observed in the mutant mice. Osterix＋ osteoprogenitors and osteocalcin＋ osteoblasts significantly reduced at the secondary spongiosa area, but only moderately decreased at the primary spongiosa area in mutant mice. Bone marrow MSCs from the mutant mice showed decreased colony forming, cell viability and cell proliferation. Thus, LRP6 in bone marrow MSCs is essential for their survival and proliferation, and therefore, is a key positive regulator for bone formation during skeletal growth and remodeling.

关键词： bone LRP6 in mesenchymal stem cells is required for bone formation during bone growth and bone remodeling stem

Development of a Self-Recording Per-Minute Precipitation Dataset for China

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Journal of Meteorological Research 2019年第6期33卷 1157-1167页

作者： Xiaohui JU Shaoping HUANG changjun li Jun li Yunjian ZHAN Shaohua FAN National Meteorological Information Center China Meteorological AdministrationBeijing 100081 Jiangxi Meteorological Information Center Nanchang 330096 Shandong Meteorological Information Center Jinan 250031 Department of Forecasting and Networking China Meteorological AdministrationBeijing 100081

The establishment of self-recording precipitation observation systems in China began in 1951,and strips of self-recording precipitation graph paper have been archived since *** than 9 million sheets of self-recording graph paper from 2253 stations in 31 provinces have been digitized by using image scanning and curve extraction *** specification and quality control have been applied to the digitized data,and the China Surface Self-Recording Per-Minute Precipitation Dataset(V1.0)has been *** integrity and accuracy of this dataset are *** is the first attempt in China to establish a per-minute precipitation dataset that covers the period from1951 to *** evaluation reveals that the station density is high and the data continuity is good in most areas of ***,the integrity of stations in some areas of western China is relatively *** availability rate and accuracy rate in summer are higher than 99%at most stations,with the overall availability and accuracy rates reaching as much as 99.42%and 99.22%,respectively.

关键词： precipitation recording paper siphon rain gauge tipping bucket rain gauge digitalization curve extraction per-minute precipitation data datasets

Endocrine role of bone in the regulation of energy metabolism

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Bone Research 2021年第4期9卷 425-443页

作者： Ruoyu Zhou Qiaoyue Guo Ye Xiao Qi Guo Yan Huang changjun li Xianghang Luo Department of Endocrinology Endocrinology Research CenterXiangya Hospital of Central South UniversityChangshaHunanChina

Bone mainly functions as a supportive framework for the whole body and is the major regulator of calcium homeostasis and hematopoietic ***,an increasing number of studies have characterized the significance of bone as an endocrine organ,suggesting that bone-derived factors regulate local bone metabolism and metabolic *** addition,these factors can regulate global energy homeostasis by altering insulin sensitivity,feeding behavior,and adipocyte *** findings may provide a new pathological mechanism for related metabolic diseases or be used in the diagnosis,treatment,and prevention of metabolic diseases such as osteoporosis,obesity,and diabetes *** this review,we summarize the regulatory effect of bone and bone-derived factors on energy metabolism and discuss directions for future research.

关键词： metabolism homeostasis prevention

Optimal root system strategies for desert phreatophytic seedlings in the search for groundwater

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Journal of Arid Land 2015年第4期7卷 462-474页

作者： li changjun ZENG Fanjiang ZHANG Bo liU Bo GUO Zichun GAO Huanhuan TIYIP Tashpolat State Key Laboratory of Desert and Oasis Ecology Xinjiang Institute of Ecology and GeographyChinese Academy of Sciences College of Resources and Environment Science Xinjiang University Cele National Station of Observation and Research for Desert Grassland Ecosystem Xinjiang Institute of Ecology and GeographyChinese Academy of Sciences Key Laboratory of Biogeography and Bioresource in Arid Land Xinjiang Institute of Ecology and GeographyChinese Academy ofSciences University of Chinese Academy of Sciences

Desert phreatophytes are greatly dependent on groundwater, but how their root systems adapt to different groundwater depths is poorly understood. In the present study, shoot and root growths of Alhagi sparsifolia Shap. seedlings were studied across a gradient of groundwater depths. Leaves, stems and roots of different orders were measured after 120 days of different groundwater treatments. Results indicated that the depth of soil wetting front and the vertical distribution of soil water contents were highly controlled by groundwater depths. The shoot growth and biomass of A. sparsifolia decreased, but the root growth and rooting depth increased under deeper groundwater conditions. The higher ratios of root biomass, root/shoot and root length/leaf area under deeper groundwater conditions implied that seedlings of A. sparsifolia economized carbon cost on their shoot growths. The roots of A. sparsifolia distributed evenly around the soil wetting fronts under deeper groundwater conditions. Root diameters and root lengths of all orders were correlated with soil water availabilities both within and among treatments. Seedlings of A. sparsifolia produced finer first- and second-order roots but larger third- and fourth-order roots in dry soils. The results demonstrated that the root systems of desert phreatophytes can be optimized to acquire groundwater resources and maximize seedling growth by balancing the costs of carbon gain.

关键词： desert phreatophytes root system strategy groundwater depth soil water biomass partition

PCLAF induces bone marrow adipocyte senescence and contributes to skeletal aging

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Bone Research 2024年第3期12卷 595-610页

作者： lingqi Xie Yalun Cheng Biao Hu Xin Chen Yuze An Zhuying Xia Guangping Cai changjun li Hui Peng Department of Endocrinology Endocrinology Research CenterXiangya Hospital of Central South UniversityChangshaHunan 410008China National Clinical Research Center for Geriatric Disorders Xiangya HospitalChangshaHunan 410008China Key Laboratory of Organ Injury Aging and Regenerative Medicine of Hunan ProvinceChangshaHunan 410008China

Bone marrow adipocytes(BMAds)affect bone homeostasis,but the mechanism remains ***,we showed that exercise inhibited PCNA clamp-associated factor(PCLAF)secretion from the bone marrow macrophages to inhibit BMAds senes... 详细信息

关键词： skeletal inhibited homeostasis

Characterization of dust collected in EAST after 2019 campaign

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Plasma Science and Technology 2021年第7期23卷 39-44页

作者： Kun ZHANG Rui DING Jiao PENG Rong YAN Junling CHEN Dahuan ZHU changjun li Xiongyuan SI Institute of Plasma Physics Hefei Institutes of Physical ScienceChinese Academy of SciencesHefei 230031People’s Republic of China University of Science and Technology of China Hefei 230026People’s Republic of China Biotechnology Center Anhui Agricultural UniversityHefei 230026People’s Republic of China

Dust presented in experimental advanced superconducting tokamak(EAST)with mixed plasmafacing materials has been collected and characterized for the first *** at different positions in the vessel was collected by vacuum cleaner after the first experimental campaign in *** shape,composition,and size of dust particles have been analyzed using different *** 80%of the total number of dust particles have size between 20 and 80μm,and most of dust particles are spherical,while schistose shape,columnar and irregular shape were also *** the help of energy-dispersive x-ray spectroscopy different elements of dust have been identified,which is generally consistent with the different plasma-facing components in *** x-ray fluorescence and inductively coupled plasma emission spectrometer are complementary methods for measuring the dust composition *** was found that the major components of dust were lithium dust in the form of lithium carbonate and lithium hydroxide,which is due to the routine lithium wall conditioning during EAST operation.

关键词： tokamak dust morphology composition analysis