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Gravity-based heuristic for set covering problems and its application in fault diagnosis

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Journal of Systems Engineering and Electronics 2012年第3期23卷 391-398页

作者： yun li Zhiming Cai Naval University of Engineering Wuhan 430033 E R. China Troops 54645 of the PLA Zhanjiang 524022 P. R. China

A novel algorithm named randomized binary gravita- tional search （RBGS） algorithm is proposed for the set covering problem （SCP）. It differs from previous SCP approaches because it does not work directly on the SCP matrix. In the proposed algo- rithm, the solution of SCP is viewed as multi-dimension position of objects in the binary search space. All objects in the space attract each other by the gravity force, and this force causes a global movement of all objects towards the objects with heavier masses which correspond to good solutions. Computation results show that the proposed algorithm is very competitive. In addition, the proposed aigodthm is extended for SCP to solve the fault diagno- sis problem in graph-based systems.

关键词： set covering problem (SCP) gravity force binary search space fault diagnosis.

Association between Serum Ferritin Levels and Metabolic-associated Fatty liver Disease in Adults:a Cross-sectional Study Based on the NHANES

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Current Medical Science 2024年第3期44卷 494-502页

作者： Jiang-hui li xue-yao MA yun YI Lu-rao li Zhi-yong XU Ying CHANG Department of Gastroenterology Zhongnan Hospital of Wuhan UniversityWuhan430071China Hubei Clinical Center and Key Laboratory of Intestinal and Colorectal Diseases Wuhan430071China Endoscopy Center The People’s Hospital of YingshanHuanggang438799China

Objective Ferritin,initially acting as an iron-storage protein,was found to be associated with metabolic *** study was designed to investigate the association between serum ferritin and metabolic-associated fatty liver disease(MAFLD)using data from the National Health and Nutrition Examination Survey(NHANES)of the United State of *** A cross-sectional study was conducted,enrolling a total of 2145 participants from the NHANES in the 2017–2018 *** steatosis and liver fibrosis were assessed by ultrasound images and several non-invasive *** regression analysis was conducted to determine the associations between serum ferritin concentration and MAFLD and liver *** The analysis revealed that participants with higher serum ferritin levels(Q3 and Q4 groups)had a higher prevalence of MAFLD than those with the lowest serum ferritin levels[Q3 vs.Q1:OR=2.17(1.33,3.53),Pliver index(Fli);Q4 vs.Q1:OR=3.13(1.91,5.13),Pli].Additionally,participants with the highest serum ferritin levels(Q4 group)displayed a higher prevalence of liver fibrosis[Q4 vs.Q1:OR=2.59(1.19,5.62),Pliver stiffness measurement;OR=5.06(1.12,22.94),Pliver fibrosis in *** serum ferritin levels combined with diabetes are important risk factors for liver fibrosis.

关键词： serum ferritin liver fibrosis metabolic-associated fatty liver disease National Health and Nutrition Examination Survey

Accumulation and bioavailability of heavy metals in a soil-wheat/maize system with long-term sewage sludge amendments

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Journal of Integrative Agriculture 2018年第8期17卷 1861-1870页

作者： YANG Guo-hang ZHU Guang-yun li He-lian HAN xue-mei li Ju-mei MA Yi-bing School of Resources and Environment University of Jinan Institute of Agricultural Resources and Regional Planning Chinese Academy of Agricultural Sciences

A long-term field experiment was carried out with a wheat-maize rotation system to investigate the accumulation and bioavailability of heavy metals in a calcareous soil at different rates of sewage sludge amendment. There are significant linear correlations between the contents of Hg, Zn, Cu, Pb, and Cd in soil and sewage sludge amendment rates. By increasing 1 ton of applied sludge per hectare per year in soil, the contents of Hg, Zn, Cu, Pb, and Cd in soil increased by 6.20, 619, 92.9, 49.2, and 0.500 μg kg–1, respectively. For Hg, sewage sludge could be safely applied to the soil for 18 years at an application rate of 7.5 t ha–1 before content exceeded the soil environmental quality standards in China(1 mg kg–1). The safe application period for Zn is 51 years and is even longer for other heavy metals(112 years for Cu, 224 years for Cd, and 902 years for Pb) at an application rate of 7.5 t ha–1 sewage sludge. The contents of Zn and Ni in wheat grains and Zn, Cu, and Cr in maize grains increased linearly with increasing sewage sludge amendment rates. The contents of Zn, Cr, and Ni in wheat straws and Zn, Cu, and As in maize straws were positively correlated with sewage sludge amendment rates, while the content of Cu in wheat straws and Cr in maize straws showed the opposite trend. The bioconcentration factors of the heavy metals in wheat and maize grains were found to be in the order of Zn>Cu>Cd>Hg>Cr=Ni>Pb>As. Furthermore, the bioconcentration factors of heavy metals in wheat were greater than those in maize, indicating that wheat is more sensitive than maize as an indicator plant. These results will be helpful in developing the critical loads for sewage sludge amendment in calcareous soils.

关键词： sewage sludge agricultural use heavy metals calcareous soil bioconcentration factors

Effect of land-use and land-cover change on nutrients in soil in Bashang area,China

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Journal of Environmental Sciences 2003年第4期15卷 548-553页

作者： SHENG xue-bin SUN Jian-zhong liU yun-xia Research Center for Eco Environmental Sciences Chinese Academy of SciencesBeijing 100085China.

The Bashang area is a water source area and ecological barrier zone for Beijing and Tianjin. The area is located at 200 km from Beijing and Tianjin and is a typical agriculture pasture interlacing zone, in which the eco environment is vulnerable and hence it is sensitive to environmental change. The area is relatively lagged in social and economic development, where the traditional cultivation mode is predominated in agriculture and animal husbandry, but the disturbance by human activity is relatively small. Therefore, in order to reveal the interrelation between eco environmental change in the area and environmental change in Beijing and Tianjin area, it is fairly necessary to study the effect of land use and land cover change on nutrients in soil in this area. According to the actual situation of changed land use for the limited time period, five series of changed land plots were selected and 4 samples were collected from each series for the study. The samples were collected from different soil forming levels at the same site in different time. Analysis of the collected samples indicates that in the process of change of land use and land cover, the nutrients in soil, such as organic matter, total N, total P, total K, and available N, P, K, and B, Mo, Mn, Zn, Cu, and Fe, have regularly changed. When the land had changed from grassland and non irrigated farmland into woodland, and from non irrigated farmland into irrigated field, the nutrients in soil totally increased. But there exists some exception, i.e. quick acting N, P, K, and some microelements have appeared to be inconsistent with the mentioned above regularity in some cases.

关键词： Bashang area land use change variation of nutrients

Photon Distribution of a Squeezed Chaotic State

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Chinese Physics Letters 2011年第4期28卷 22-24页

作者： FAN Hong-Yi ZHOU Jun XU xue-Xiang HU li-yun Department of Material Science and Engineering University of Science and Technology of ChinaHefei 230026 Department of Material and Chemical Engineering West Anhui UniversityLu’an 237012 College of Physics and Communication Electronics Jiangxi Normal UniversityNanchang 330022

We investigate the photon number distribution of squeezed chaotic field(SCF)(a mixed state),by converting the density operator of SCF into its normally ordered bivariate distribution form we find that it is a Legendre... 详细信息

关键词： chaotic distribution ordered

Lung stem cells in regeneration and tumorigenesis

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Journal of Genetics and Genomics 2021年第4期48卷 268-276页

作者： Yuting Chen yun xue Yujuan Jin Hongbin Ji State Key Laboratory of Cell Biology Shanghai Institute of Biochemistry and Cell BiologyCenter for Excellence in Molecular Cell ScienceChinese Academy of SciencesUniversity of Chinese Academy of SciencesShanghai 200031China School of life Science and Technology ShanghaiTech UniversityShanghai 201210China Shanghai Pulmonary Hospital Tongji UniversityShanghai 200092China

Adult lung is a highly quiescent organ,with extremely low cell turnover ***,emerging evidences support the occurrence of repair and regeneration in pulmonary epithelia in response to various *** regeneration mainly depends on the proliferation of regionally distributed pulmonary stem cells that re-enter the cell *** lineage-tracing approaches help to track the lung epithelial differentiation and/or de-differentiation path,and single-cell transcriptomic technique reveals the essential molecular signaling involved in lung *** of the molecular signaling that balances quiescence and self-renewal leads to the transformation of lung stem cells,and thus promotes lung cancer ***,different subtypes of lung cancer share common cells of origin and the pathological transition among various subtypes is responsible for drug resistance in the *** this review,we summarize the recent understanding of lung stem cells in regeneration and tumorigenesis as well as related molecular mechanisms,with the hope to provide helpful insights for clinical treatments of respiratory diseases.

关键词： Lung stem cells Lung cancer Regeneration Tumorigenesis Pathological transition

Non-cell autonomous role of astrocytes in axonal degeneration of cortical projection neurons in hereditary spastic paraplegias

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Neural Regeneration Research 2022年第6期17卷 1265-1266页

作者： xue-Jun li Department of Biomedical Sciences University of Illinois College of Medicine RockfordRockfordILUSA Department of Bioengineering University of Illinois at ChicagoChicagoILUSA

Impai red axonal deve lopment and degeneration underlie many debilitating diseases,including hereditary spastic paraplegia(HSP).HSPs are a heterogeneous group of neurogenetic disorders characterized by axonopathy of cortical motor neurons(Fink,2006;Blackstone et al.,2010).The axonal degeneration of these cortical projection neurons(PNs)in HSP patients disrupts the signals from brain to spinal motor neurons,leading to muscle weakness and *** the discovery of the first HSP gene(SPAST)in 1999,over 80 distinct genetic loci associated with HSP have been *** the mutations of these divergent genes specifically result in axonal degeneration of cortical PNs remains largely unclear,which contributes to the lack of effective treatment to ameliorate,stop,or reverse axonal defects in HSPs.

关键词： degeneration axonal projection

Molecular Dynamics Study of Interaction between Acrylamide Copolymers and Alumina Crystal

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Chinese Journal of Chemical Physics 2012年第5期25卷 571-576,I0003,I0004页

作者： Feng-he Wang Feng-yun Wang xue-dong Gong Department of Environmental Science and Engineering Nanjing Normal UniversityNanjing 210042China Department of Chemistry Nanjing University of Science and TechnologyNanjing 210094China

Four acrylamide polymer flocculants, anionic polyacrylamide P（AA-co-AM）, cationic poly- acrylamide P（DMB-co-AM）, nonionic polyacrylamide P（AM）, and hydrophobical polyacry- lamide P（OA-co-AM） have been prepared by copolymerizing with acrylic acid, cationic monomer dimethylethyl （acryloxyethyl） ammonium bromide （DMB） and hydrophobical monomer octadecyl acrylate with acrylamide. The interactions between the flocculants with the （012） surface of alumina crystal （A1203） have been simulated by molecular dynamics method. All the polymers can bind tightly with A1203 crystal, the interaction between the O of polymers and A1 of the （012） surface of A1203 is significantly strong. The order of binding energy is as follows： P（DMB-co-AM）〉P（OA-co-AM）〉P（AA-co-AM）〉P（AM）, implying a better flocculation performance of P（DMB-co-AM） than the others. Analy- sis indicates that binding energy is mainly determined by Coulomb interaction. Bonds are found between the O atoms of the polymers and the A1 atoms of A1203. The poly- mers＇ structures deform when they combine with A1203 crystal, but the deformation en- ergies are low and far less than non-bonding energies. Flocculation experiments in sus- pension medium of l%Kaolin show a transmittancy of 90.8% for 6 mg/L P（DMB-co-AM） and 73.0% for P（AM）. The sequence of flocculation performance of four polymers is P（DMB-co-AM）〉P（OA-co-AM）〉P（AA-co-AM）〉P（AM）, which is in excellent agreement with the simulation results of binding energy.

关键词： Molecular dynamics simulation Acrylamide copolymer Binding energy Floc-culation

Altering elastic-plastic mechanical response of a series of isostructural metal-organic complex crystals

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Science China Chemistry 2022年第4期65卷 710-718页

作者： Zheng Tang Xiao-Peng Sun Shu-Dong Wang xue-Yang Ji yun li Zi-Shuo Yao Jun Tao Key Laboratory of Cluster Science of Ministry of Education School of Chemistry and Chemical EngineeringBeijing Institute of TechnologyBeijing 100081China Henan Key Laboratory of Polyoxometalate Chemistry College of Chemistry and Chemical EngineeringHenan UniversityKaifeng 475004China

The mechanically compliant single crystals have attracted massive ***,the related reports on the single crystals composed of metal-organic complexes remain *** this study,we synthesized a series of isostructural single crystals of Zn^(Ⅱ) complexes that manifest mechanical bending in response to external *** these crystals,the mechanical responses can be shifted between elastic bending and plastic bending by the control of the intermolecular interactions through a rational structural modification in the substituent group of pyridine *** the molecular reorientation corresponding to ligand variation elongates the interfacial distance between molecular slip planes,and the structural disorder of ligands disperses the interplanar intermolecular interactions,the shift from elastic bending to plastic bending of the metal-organic complex-based single crystal was *** different mechanical responses of single crystals were comprehensively investigated both experimentally and theoretically.

关键词： mechanical property flexible crystals crystal engineering metal-organic complex intermolecular interaction