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Estimating Stem Volume Using QuickBird Imagery and Allometric Relationships for Open Populus xiaohei Plantations

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Journal of Integrative Plant Biology 2007年第9期49卷 1304-1312页

作者： Xiao-qing Wang zeng-Yuan Li Xing-E Liu Guang Deng Ze-hui Jiang Research Institute of Wood Industry Chinese Academy of Forestry Beijing 100091 China Research Institute of Forest Resource Information Techniques Chinese Academy of Forestry Beijing 100091 China Intemational Centre for Bamboo and Rattan Beijing 100102 China)

There has been a great deal of interest in studying the crown of trees using remote sensing data. In this study, crown width was extracted from high-resolution QuickBird images for open Populus xiaohei plantations. Regression models for predicting the individual stem volumes of Populus xiaohei were established using extracted crown width, as well as estimated tree parameters （i.e. diameter at breast height [DBH] and tree height） as predictors. Our results indicated that crown width could be accurately extracted from QuickBird images using a multi-scale segmentation approach with a mean relative error of 5.74%, especially for wide-spacing stands. Using either extracted crown width alone or with estimated DBH and tree height can successfully estimate individual stem volume of Populus xiaohei with the R2 value ranging from 0.87 to 0.92 depending on different model forms. In particular, the two second-order polynomial models （model 2 and model 6）, based on QuickBird image-derived crown widths and estimated DBH and tree heights, respectively, were the best at describing the relationship between stem volume and tree characteristics.

关键词： diameter at breast height Populus xiaohei QuickBird image stem volume tree crown tree height.

One hour of pilocarpine-induced status epilepticus is sufficient to develop chronic epilepsy in mice, and is associated with mossy fiber sprouting but not neuronal death

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Neuroscience Bulletin 2013年第3期29卷 295-302页

作者： Ling-Lin Chen Hang-Feng Feng Xue-Xia Mao qing Ye Ling-hui zeng Department of Pharmacology College of Medicine Zhejiang University Department of Pharmacy Zhejiang University City College

Determining the minimal duration of status epilepticus （SE） that leads to the development of subsequent spontaneous seizures （i.e., epilepsy） is important, because it provides a critical timewindow for seizure intervention and epilepsy prevention. In the present study, male ICR （imprinting Control Region） mice were injected with pilocarpine to induce acute sei zures. SE was terminated by diazepam at 10 min, 30 min, 1 h, 2 h and 4 h after seizure onset. Spon taneous seizures occurred in the 1, 2 and 4 h SE groups, and the seizure frequency increased with the prolongation of SE. Similarly, the Morris water maze revealed that the escape latency was significantly increased and the number of target quadrant cross ings was markedly decreased in the 1, 2 and 4 h SE groups. Robust mossy fiber sprouting was observed in these groups, but not in the 10 or 30 min group. In contrast, FluoroJade B staining revealed significant cell death only in the 4 h SE group. The incidence and frequency of spontaneous seizures were corre lated with Timm score （P = 0.004） and escape latency （P = 0.004）. These data suggest that SE longer than one hour results in spontaneous motor seizures and memory deficits, and spontaneous seizures are likely associated with robust mossy fiber sprouting but not neuronal death.

关键词： epileptogenesis pilocarpine Fluoro-JadeB staining Timm staining Morris water maze

Control of diffuse P-pollutants by multiple buffer/detention structures by Yuqiao Reservoir, North China

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Journal of Environmental Sciences 2004年第4期16卷 616-620页

作者： WANGXia-hui YINCheng-qing SHANBao-qing ResearchCenterforEco-EnvironmentalSciences ChineseAcademy-ofSciencesBeijing100085China

A case study on the transport process of agricultural diffuse P-pollutants was conducted in an experimental watershed locating in the north bank of Yuqiao Reservoir during 2001 and 2002. It was found that diversified artificial and natural buffer/detention landscape structures distributing along the ephemeral stream channel in this watershed played an important role of pollutants removal on downstream water quality, especially they have control effect on the diffuse P-pollutants transport process. Surface flow velocity was reduced sharply after passing through these structures. During continuous runoff events, the removal rate of TSS, TP, TDP, DRP by the whole system were 66.7%, 60.7%, 48.4%, and 43.3%, respectively. During discontinuous runoff events, removal rate of pollutants by the whole system was higher due to there was no or little surface water and pollutants exported from the watershed, of which removal rate of pollutants all exceeded 99%. The statistical analysis results of runoff events(n=8) indicated that dry pond was the steadiest structure for controlling diffuse P-pollutants export.

关键词： diffuse P-pollutants buffer/detention structures removal transport process water quality

INVERSE PROBLEM METHOD FOR WATER ENVIRONMENT TOTAL CAPACITY CONTROL OF A TIDAL RIVER

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Journal of Hydrodynamics 2005年第3期17卷 323-329页

作者： WANGDao-zeng ZHAOYu-feng LINWei-qing ShanghaiInstituteofAppliedMathematicsandMechanics ShanghaiUniversityShanghai200072China ShanghaiAcademeofEnvironmentalScience Shanghai200233China

In this paper, an improved method for water environment total capacity control of tidal rivers was presented. The maximal capacity of point pollution sources for the Huangpu River was computed by this method, and the result was compared with the practically observed data. The numerical result shows that the method is effective and efficient.

关键词： inverse problem tidal river PST-BFGS method point source pollution Huangpu River

Sensitivity Analysis of Semi-simple Eigenvalues of Regular Quadratic Eigenvalue Problems

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Acta Mathematicae Applicatae Sinica 2015年第2期31卷 499-518页

作者： hui-qing XIE Department of Mathematics East China University of Science and Technology

This paper discusses the sensitivity analysis of semisimple eigenvalues and associated eigen-matrix triples of regular quadratic eigenvalue problems analytically dependent on several parameters. The directional derivatives of semisimple eigenvalues are obtained. The average of semisimple eigenvalues and corresponding eigen-matrix triple are proved to be analytic, and their partial derivatives are given. On these grounds, the sensitivities of the semisimple eigenvalues and corresponding eigenvector matrices are defined.

关键词： sensitivity analysis quadratic eigenvalue problems multiple eigenvalue matrix-valued functions

Preparation of CdSe/ZnSe Core-shell Nanocrystal in One-step Reaction

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Chemical Research in Chinese Universities 2005年第6期21卷 728-733页

作者： FEI Xiao-fang SHAN Gui-ye KONG Xiang-gui WANG Xin zeng qing-hui ZHANG You-lin Key Laboratory of Excited State Physics Process Changchun Institute of Optic Fine Mechanics and Physics Chinese Academy of Sciences Changchun 130033 P. R. China College of Life Sciences Jilin University Changchun 130021 P. R. China Center for Advanced Optoelectronic Functional Material Research Northeast Normal University Changchun 130024 P. R. China

High-quality Zn-doped CdSe core-shell nanocrystals were successfully prepared by incorporating a stoichiometric amount of Zn precursor into the CdSe reaction system, in which the Se precursor was excess and an Se-rich surface was formed. By injecting different amounts of Zn precursor, the core-shell nanocrystals demonstrated by the emission spectra were formed. The obtained Zn-doped CdSe nanocrystals exhibit a photoluminescence efficiency from 30% to 85%, which is comparable to those for the reported CdSe/ZnS, CdSe/CdS in the literature. In particular, a shell ZnSe layer with different thicknesses of ZnSe can be formed in this experiment by only changing the amount of Zn precursor added, which is simple and effective.

关键词： CdSe/ZnSe Core-shell one-step Photoluminescence

Construction of two-dimensional(2D) H-bonded supramolecular nanostructures studied by STM

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Chinese Chemical Letters 2013年第3期24卷 177-182页

作者： Jing Xu qing-Dao zeng National Center for Nanoscience and Technology(NCNST)

In this review, a group ot two-dimensional （2D） hydrogen-bonded supramolecular networks developed in our laboratory are discussed. Our attention is mainly focused on：（1） recognition of Fe3＋ through twocomponent molecular networks; （2） site-selective fabrication of 2D fullerene arrays; and （3） fabrication of the nanoporous structure regulated by photoisomerization reaction process. It is envisioned that special supramolecular nanostructures, through H-bonding interactions, can be constructed or reconstructed to be further investigated toward the research of multi-component systems, molecule recognition, single molecular switches, and host-guest supramolecular chemistry.

关键词： Scanning tunneling microscopy (STM)Self-assemblySupramolecular networkHydrogen bonds

改良数字化导板对第二磨牙游离缺失辅助种植的精确度

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中国组织工程研究 2025年第4期29卷 738-744页

作者：张宇航曾宇宁曾尽娣卢依旋叶慧吉建新广州医科大学附属第一医院口腔科广东省广州市510120 广州信德君乐口腔门诊部有限公司广东省广州市510620

背景:静态数字化导板辅助种植可提高种植精度,但对于开口度小和种植位点牙合间距离小的患者后牙区使用较为受限,为此需要对数字化导板进行改良。目的:研究改良数字化导板对第二磨牙游离缺失辅助种植的精确度。方法:选择2020年7月至2023... 详细信息

背景:静态数字化导板辅助种植可提高种植精度,但对于开口度小和种植位点牙合间距离小的患者后牙区使用较为受限,为此需要对数字化导板进行改良。目的:研究改良数字化导板对第二磨牙游离缺失辅助种植的精确度。方法:选择2020年7月至2023年7月就诊于广州医科大学附属第一医院的第二磨牙游离缺失患者40例,采用掷硬币法随机分为试验组(n=22)与对照组(n=18),分别接受改良数字化导板辅助种植手术与常规自由手种植手术。对患者术前及术后锥形束CT进行重叠分析,比较组间的颈部偏差、尖端偏差、深度偏差、角度偏差值。术后1周,通过目测类比评分评估患者对手术过程的满意度。结果与结论:①试验组植入25颗种植体(上颌12颗,下颌13颗),对照组植入23颗种植体(上颌8颗,下颌15颗),试验组患者颈部偏差、尖端偏差、深度偏差、角度偏差值均小于对照组(P0.05);②两组患者对手术过程的满意度比较差异无显著性意义(P>0.05);③结果表明,改良数字化导板对第二磨牙游离缺失辅助种植可提高手术精度,适用于开口度小和种植位点牙合间距离小的患者后牙区。

关键词：种植精度改良种植导板第二磨牙缺失牙合间距离牙种植

Investigation of Direct Causes of Drug Relapse and Abstainers’ Demands in a Compulsive Detoxification Center in Wuhan City of China

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Biomedical and Environmental Sciences 2007年第5期20卷 404-409页

作者： zeng-ZHEN WANG qing WANG Department of Epidemiology and Health Statistics School of Public Health Tongji Medical College Huazhong University of Science and Technology Wuhan 430030 Hubei China Compulsive Detoxification Center Public Security Office Wuhan 430040 Hubei China

Objective To identify the direct causes of drug relapse and abstainers’ demand, and to develop programs for the prevention of drug relapse. Methods Abstainers in a Compulsive Detoxification Center in Wuhan City, capital of Hubei Province were randomly selected. An investigation on the direct causes of drug relapse and abstainers’ demands was conducted with multiple-choice questionnaires and face to face interviews. Data were analyzed with SPSS 12.0. Results The direct causes leading to drug relapse included： temptation to use drug again by themselves or by their drug mates, seeking pleasure and ecstasy from drug use, relatively well off living, mental stress, irritation, demoralization, family conflicts, unemployment, feeling distrusted by the family, lack of care and love from the family, and discrimination by others. abstainers’ demands after detoxification and returning to the society included： care and support from the family, employment assistance, changing living environment, understanding by others, support from the society, and keeping far away from drugs. Conclusions Environmental factors are the direct causes of drug relapse, and negative irritation is its predisposing causes. Leaving former residence, more care and help given by both the family and the society and raising their overall quality of life are the demands of abstainers.

关键词： Drug abuse Causes of drug relapse Demands