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journal of Forestry Research 2012年第2期23卷 191-196页

作者： LEI Cheng-liang jU Cun-yong CAI Ti-jiu j1ng xia WEI xiao-hua DI Xue-ying School of Forestry Northeast Forestry UniversityHarbin 150040P.R.China College of Geomatics Xi'an University of Science and TechnologyXi'an 710054P.R.China Department of Earth and Environmental Science University of BritishColumbia(Okanagan)3333 University wayKelownaBritish Colum-biaCanadaV1V 1V7.

Boreal forests play an important role in global environment systems. Understanding boreal forest ecosystem structure and function requires accurate monitoring and estimating of forest canopy and biomass. We used partial least square regression （PLSR） models to relate forest parameters, i.e. canopy closure density and above ground tree biomass, to Landsat ETM＋ data. The established models were optimized according to the variable importance for projection （VIP） criterion and the bootstrap method, and their performance was compared using several statistical indices. All variables selected by the VIP criterion passed the bootstrap test （p〈0.05）. The simplified models without insignificant variables （VIP 〈1） performed as well as the full model but with less computation time. The relative root mean square error （RMSE%） was 29% for canopy closure density, and 58% for above ground tree biomass. We conclude that PLSR can be an effective method for estimating canopy closure density and above ground biomass.

关键词： above-ground tree biomass bootstrap method canopy clo- sure density partial least square regression (PLSR) VIP criterion

CaH2-promoted activity of Ni-carbonate interface for CO2 methanation

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journal of Energy Chemistry 2025年第1期100卷 522-532页

作者： jin-Peng Wang Guo-Cui Mao Hui-Lin jiang Bao-xia Dong Yun-Lei Teng School of Chemistry and Chemical Engineering Yangzhou University

Transition metal-carbonate interfaces often act as active sites in heterogeneous catalytic *** interface between transition metal and metal carbonate exhibits a dynamic equilibrium during the CO2hydrogenation reaction,involving surface carbonate hydrogenation and ***,there have been few reports on engineering the activity of the interface between transition metal and alkaline earth metal carbonate for catalytic *** work demonstrated that the incorporation of CaH2in Ni/CaCO3enhances the CO2methanation activity of the *** CO2conversion for Ni/CaH2-CaCO3reached 68.5%at 400°C,which was much higher than that of the Ni/CaCO3（31.6%） and Ni/CaH2-CaO （42.4%） ***,the Ni/CaH2-CaCO3catalysts remained stable during the stability test for 24 h at 400°C and 8 *** research revealed that CaH2played a crucial role in promoting the activity of the Ni-carbonate interface for ***2could modify the electronic structure of Ni and tune the structural properties of CaCO3to generate medium basic sites （OH groups）,which are favorable for the activation of H2and ***-situ Fourier transform infrared spectroscopy （FTIR） analysis combined with density functional theory calculations demonstrated that CO2activation occurs at the hydroxyl group （OH） on the CaH2-modified Ni-carbonate surface,leading to the formation of CO3H****,our study has confirmed that CO2methanation over the Ni/CaH2-CaCO3catalysts proceeds via the formate pathway.

关键词： Metal hydride Ni catalysts Carbonate Metal-carbonate interface

Recombinant chitinase-3-like protein 1 alleviates learning and memory impairments via M2 microglia polarization in postoperative cognitive dysfunction mice

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Neural Regeneration Research 2025年第9期20卷 2727-2736页

作者： Yujia Liu Xue Han Yan Su Yiming Zhou Minhui Xu jiyan Xu Zhengliang Ma xiaoping Gu Tianjiao xia Department of Anesthesiology Nanjing Drum Tower HospitalAffiliated Hospital of Medical SchoolNanjing UniversityNanjingJiangsu ProvinceChina Medical School Nanjing UniversityNanjingJiangsu ProvinceChina jiangsu Key Laboratory of Molecular Medicine Nanjing UniversityNanjingJiangsu ProvinceChina State Key Laboratory of Pharmaceutical Biotechnology Nanjing UniversityNanjingJiangsu ProvinceChina Department of Anesthesiology Zhongshan HospitalFudan UniversityShanghaiChina

Postoperative cognitive dysfunction is a seve re complication of the central nervous system that occurs after anesthesia and surgery,and has received attention for its high incidence and effect on the quality of life of *** date,there are no viable treatment options for postoperative cognitive *** identification of postoperative cognitive dysfunction hub genes could provide new research directions and therapeutic targets for future *** identify the signaling mechanisms contributing to postoperative cognitive dysfunction,we first conducted Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analyses of the Gene Expression Omnibus GSE95426 dataset,which consists of mRNAs and long non-coding RNAs differentially expressed in mouse hippocampus3 days after tibial *** dataset was enriched in genes associated with the biological process"regulation of immune cells,"of which Chill was identified as a hub ***,we investigated the contribution of chitinase-3-like protein 1 protein expression changes to postoperative cognitive dysfunction in the mouse model of tibial fractu re *** were intraperitoneally injected with vehicle or recombinant chitinase-3-like protein 124 hours post-surgery,and the injection groups were compared with untreated control mice for learning and memory capacities using the Y-maze and fear conditioning *** addition,protein expression levels of proinflammatory factors(interleukin-1βand inducible nitric oxide synthase),M2-type macrophage markers(CD206 and arginase-1),and cognition-related proteins(brain-derived neurotropic factor and phosphorylated NMDA receptor subunit NR2B)were measured in hippocampus by western *** with recombinant chitinase-3-like protein 1 prevented surgery-induced cognitive impairment,downregulated interleukin-1βand nducible nitric oxide synthase expression,and upregulated CD206,arginase-1,pNR2B,and brain-derived neurotropic factor expr

关键词： Chil1 hippocampus learning and memory M2 microglia neuroinflammation postoperative cognitive dysfunction(POCD) recombinant CHI3L1

Effects of histone deacetylase inhibitors on transcriptional regulation of the hsp70 gene in Drosophila

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Cell Research 2006年第6期16卷 566-576页

作者： Yan Mei Zhao~(1,*) xia Chen~(1,*) Hui Sun~1 Zhi Gen Yuan~1 Guo Ling Ren~1 xiao Xue Li~1 jun Lu~1 Bai Qu Huang~1 ~1The Institute of Genetics and The Institute of Genetics and Cytology Northeast Normal University Changchun China

Histone acetyltransferases/deacetylases contribute to the activation or inactivation of transcription by modifying thestructure of *** we examined the effects of histone deacetylase inhibitors(HDIs),trichostatin A,and sodiumbutyrate on hsp 70 gene transcriptional regulation in *** chromatin immunoprecipitation assays revealedthat HDI treatments induced the hyperacetylation of histone H3 at the promoter and the transcribing regions of hsp70gene,increased the accessibility of heat-shock factor to target heat-shock element,and promoted the RNA polymeraseⅡ-mediated ***,the quantitative real-time PCR confirmed that the HDI-induced hyperacetylation ofhistone H3 enhanced both the basal and the inducible expression of hsp70 mRNA *** addition,the acetylation levelof histone H3 at the promoter exhibited a fluctuated change upon the time of heat *** experimental data impli-cated a causal link between histone acetylation and enhanced transcription initiation of hsp70 gene in Drosophila.

关键词： histone acetylation hsp70 histone deacetylase inhibitor Drosophila melanogaster

Photometric investigation and orbital period analyses of the W UMa binaries FP Lyn, FV CVn and V354 UMa

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Research in Astronomy and Astrophysics 2019年第7期19卷 103-114页

作者： Raul Michel Qi-Qi xia jesus Higuera1 Observatorio Astronomico Nacional Instituto de AstronomíaUniversidad Nacional Autońoma de MéxicoApartado Postal 877EnsenadaB.C.22830Mexico Shandong Provincial Key Laboratory of Optical Astronomy and Solar-Terrestrial Environment Institute of Space SciencesShandong UniversityWeihai 264209China

New light curves and photometric solutions of FP Lyn,FV CVn and V354 UMa are *** found that these three systems are W-subtype shallow contact *** addition,it is obvious that the light curves of FP Lyn and V354 UMa are ***,a hot spot was added on the primary star of FP Lyn and a dark spot was added on the secondary star of V354 *** the same time,we added a third light to the photometric solution of FP Lyn for the final *** obtained mass ratios and fill-out factors are q = 1.153 and f = 13.4% for FP Lyn,q = 1.075 and f = 4.6% for FV CVn,and q = 3.623 and f = 10.7% for V354 UMa *** investigations of orbital period for these three systems indicate that the periods are *** Lyn and V354 UMa were discovered to have secularly increasing components with rates of dp/dt = 4.19 ×10^-7 dyr^-1 and dp/dt = 7.70 ×10^-7 dyr^-1 respectively,which are feasibly caused by conservative mass transfer from the less massive component to the more massive *** addition,some variable components were discovered for FV CVn,including a rate of dp/dt =-1.13 ×10^-6 dyr^-1 accompanied by a cyclic oscillation with amplitude and period of 0.0069 d and 10.65 yr *** most likely explanation for the long-term decrease is angular momentum *** existence of an additional star is the most plausible explanation for the periodic variation.

关键词： stars:binaries:close stars:binaries:eclipsing stars:individual (FP Lyn, FV CVn and V354 UMa)

Perilipin-2 mediates ferroptosis in oligodendrocyte progenitor cells and myelin injury after ischemic stroke

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Neural Regeneration Research 2025年第7期20卷 2015-2028页

作者： jian Yang jiang Wu Xueshun Xie Pengfei xia jinxin Lu jiale Liu Lei Bai xiang Li Zhengquan Yu Haiying Li Department of Neurosurgery&Brain and Nerve Research Laboratory The First Affiliated Hospital of Soochow UniversitySuzhouJiangsu ProvinceChina Institute of Stroke Research Soochow UniversitySuzhouJiangsu ProvinceChina

Differentiation of oligodendrocyte progenitor cells into mature myelin-forming oligodendrocytes contributes to *** of remyelination due to oligodendrocyte progenitor cell death can result in severe nerve *** is an iron-dependent form of regulated cell death caused by membrane rupture induced by lipid peroxidation,and plays an important role in the pathological process of ischemic ***,there are few studies on oligodendrocyte progenitor cell *** analyzed transcriptome sequencing data from GEO databases and identified a role of ferroptosis in oligodendrocyte progenitor cell death and myelin injury after cerebral *** analysis suggested that perilipin-2(PLIN2)was involved in oligodendrocyte progenitor cell ***2 is a lipid storage protein and a marker of hypoxia-sensitive lipid droplet *** further investigation,we established a mouse model of cerebral ischemia/*** found significant myelin damage after cerebral ischemia,as well as oligodendrocyte progenitor cell death and increased lipid peroxidation levels around the infarct *** ferroptosis inhibitor,ferrostatin-1,rescued oligodendrocyte progenitor cell death and subsequent myelin *** also found increased PLIN2 levels in the peri-infarct area that co-localized with oligodendrocyte progenitor ***2 knockdown rescued demyelination and improved neurological *** findings suggest that targeting PLIN2 to regulate oligodendrocyte progenitor cell ferroptosis may be a potential therapeutic strategy for rescuing myelin damage after cerebral ischemia.

关键词： bioinformatics bulk RNA sequencing ferroptosis ischemic stroke myelin injury oligodendrocyte progenitor cell perilipin-2 single-cell RNA sequencing

Actively tunable electromagnetically induced transparency in hybrid Dirac-VO2 metamaterials

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Optoelectronics Letters 2025年第1期21卷 13-20页

作者： DI Ke XIE Meng xia Huarong CHEng Anyu LIU Yu DU jiajia Department of Optoelectronic Engineering Chongqing University of Post and Telecommunications Chongqing Key Laboratory of Autonomous Navigation and Microsystem Chongqing University of Posts and Telecommunications Department of Automation Chongqing University of Post and Telecommunications

In this paper, we present a metamaterial structure of Dirac and vanadium dioxide（VO2） and investigate its optical properties using the finite-difference time-domain（FDTD） technique. Using the phase transition feature of VO2, the design can realize active tuning of the plasmon induced transparency（PIT） effect at terahertz frequency, thereby converting from a single PIT to a double-PIT. When VO2is in the insulating state, the structure is symmetric to obtain a single-band PIT effect. When VO2is in the metallic state, the structure turns asymmetric to realize a dual-band PIT effect. This design provides a reference direction for the design of actively tunable metamaterials. Additionally, it is discovered that the transparent window's resonant frequency and the Fermi level in this structure have a somewhat linear relationship. In addition, the structure achieves superior refractive index sensitivity in the terahertz band, surpassing 1 THz/RIU. Consequently, the design exhibits encouraging potential for application in refractive index sensors and optical switches.

关键词： Transparency

论新时代全面深化改革的历史逻辑、理论逻辑和现实逻辑

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新疆师范大学学报（哲学社会科学版） 2025年第1期46卷 50-59页

作者：张夏恒西北政法大学商学院(管理学院) 陕西西安710122

新时代全面深化改革具有深厚的历史逻辑、丰富的理论逻辑和鲜明的现实逻辑。从历史逻辑看,全面深化改革始于党的十一届三中全会,提出于党的十八届三中全会,成熟于党的二十届三中全会。从理论逻辑看,全面深化改革概念历经从改革与开放到... 详细信息

新时代全面深化改革具有深厚的历史逻辑、丰富的理论逻辑和鲜明的现实逻辑。从历史逻辑看,全面深化改革始于党的十一届三中全会,提出于党的十八届三中全会,成熟于党的二十届三中全会。从理论逻辑看,全面深化改革概念历经从改革与开放到改革开放,从全面改革到深化改革,再从全面改革、深化改革到全面深化改革的演化,全面深化改革以马克思主义、党的领导、中国特色社会主义、习近平新时代中国特色社会主义思想等为理论支撑。从现实逻辑看,新时代全面深化改革不仅体现了中国特色社会主义进入新时代改革的重要性与必要性,而且全面深化改革是应对中国改革面临的诸多挑战和机遇的时代选择,要将以人民为中心、坚持党的领导、推进国家治理体系和治理能力现代化、坚持社会主义制度、构建高水平社会主义市场经济体制、因地制宜发展新质生产力等作为新时代全面深化改革的现实抓手与工作重心。

关键词：新时代全面深化改革改革开放党的二十届三中全会党的十八届三中全会党的十一届三中全会

Microstructures of mechanically activated Ti-46at.%Al powders and spark plasma sintered ultrafine TiAl alloy

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Rare Metals 2007年第6期26卷 572-577页

作者： xia Li DIng Hui Ruan Xuefong REN Yaoyao College of Power and Mechanical Engineering Wuhan University Wuhan 430072 China School of Physicals Wuhan University Wuhan 430072 China

Powder of Ti-46at.%Al was synthesized through mechanical activation （MA） for different milling times, and the 16 h MAed powder was sintered by using a spark plasma sintering （SPS） process at different sintering temperatures. The XRD profiles showed that the MAed Ti-46at,%Al powder for 12, 16, and 20 h contained initial α-Ti and Al phases, and that the SPSed TiAl alloys contained the gamma TiAl and α2-Ti3Al phases. The TEM showed two different types of regions in the 16 h MAed Ti-46at.%Al powder. One type consisted of only Al with a grain size about 80 nm, and the other type a mixture of Al and Ti with a grain size of 30 nm. According to the optical micrographs of MA-SPSed samples, the alloys sintered at higher temperatures showed a coarser microstructure. In the case of the 1473 Ksintering, typical duplex structures （（α2 ＋γ） lamella and γ phases） with interlamellar spacings of 50-400 nm and the grain size either less than 100 nm, or 1000 nm were observed.

关键词： metal materials titanium aluminides spark plasma sintering (SPS) mechanical activation (MA)

动态序列情境对面部表情知觉的影响和作用机制

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心理科学进展 2025年第1期33卷 1-10页

作者：方霞潘之禾浙江大学心理与行为科学系杭州310058

现实生活中,面部表情通常随时间推移呈动态变化,个体对任一表情的解读都可能受其所处的动态序列情境的影响。尽管近年来有研究表明同时呈现的情境信息会对目标表情的知觉产生影响,但对于序列变化的表情信息如何影响目标表情知觉却知之... 详细信息

现实生活中,面部表情通常随时间推移呈动态变化,个体对任一表情的解读都可能受其所处的动态序列情境的影响。尽管近年来有研究表明同时呈现的情境信息会对目标表情的知觉产生影响,但对于序列变化的表情信息如何影响目标表情知觉却知之甚少。本研究拟通过行为实验和眼动技术,借助人工合成和真人表演的动态表情,考察序列变化的表情信息(即动态序列情境)对初始表情和最终表情的知觉的影响及其作用机制。研究成果有助于揭示生态化情境下的面部表情加工机制,为基于人工智能的动态表情识别提供参考。

关键词：面部表情情绪知觉动态序列情境