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Integration method of TINs and Grids for multi-resolution surface modeling

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Geo-Spatial Information Science 2013年第1期16卷 61-68页

作者： Xie xiao Xu WEIPING Zhu qing Zhang YETING Du ZHIQIANG State Key Laboratory of Information Engineering in Surveying Mapping and Remote SensingWuhan University129 Luoyu RoadWuhan 430079China b Faculty of Geosciences and Environmental Engineering of Southwest Jiaotong University Chengdu 610031China

Highly detailed surface models and their real-time applications are increasingly popular in architecture,construction and other design and engineering ***,new and related problems have emerged concerning the efficient management of the resulting large datasets and the seamless integration of heterogeneous ***,the increasingly common requirements of local high-fidelity modeling combined with large-scale landscapes lead to difficulty in the seamless multi-resolution representation of hybrid triangulated irregular networks(TINs)and *** paper presents a hybrid data structure with high-efficiency and a related organizational method for the seamless integration of multi-resolution *** approach is characterized by(1)a self-adaptive algorithm for feature-preserving surface partitioning,(2)an efficient hybrid index structure for combined Grid and TIN surfaces,and(3)a view-dependent scheduling strategy with access to Grids of necessary resolution,giving priority to the dynamic loading of *** using typical real design datasets of highway constructions are able to achieve accuracy-preserved and real-time availability of results that prove the validity and efficiency of this approach.

关键词： surface modeling TIN Grid LoDs high fidelity

Downstream signaling of reactive oxygen species,protein kinase C epsilon translocation and delayed neuroprotection in sevoflurane preconditioned rats following cerebral ischemia/reperfusion

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Neural Regeneration Research 2009年第3期4卷 205-212页

作者： Zhi Ye Qulian guo E Wang Yundan Pan qing Li Honghao Zhou Department of Anesthesiology Xiangya Hospital Central South University Changsha 410008 Hunan Province China Institute of Cfinical Pharmacology Central South University Changsha 410078 Hunan Province China

BACKGROUND： Brief exposure to the anesthetic sevoflurane results in delayed neuroprotection, However, few studies have addressed delayed neuroprotection after preconditioning with a single administration of sevoflurane. OBJECTIVE： To explore the relationship between a single preconditioning administration of sevoflurane and reactive oxygen species production and protein kinase C-epsilon （PKC-ε ） translocation. DESIGN, TIME, AND SETTING： The randomized, controlled, animal experiment was conducted at the Central Laboratory, Xiangya Hospital, Central South University, China from November 2007 to April 2008. MATERIALS： A total of 120 healthy, male, Sprague Dawley rats were equally and randomly assigned into five groups： sham operation, ischemia/reperfusion, sevoflurane, 2-mercaptopropionylglycine （2-MPG, a selective reactive oxygen species scavenger）＋ sevoflurane （MPG ＋ sevoflurane）, and MPG. Sevoflurane （Baxter, USA） and MPG （Sigma, USA） were used in this study. METHODS： Intervention consisted of three procedures. （1） MPG injection： a selective reactive oxygen species scavenger, MPG （20 mg/kg）, was infused into the rat caudal vein in the MPG and MPG ＋ sevoflurane groups. （2） Sevoflurane preconditioning： 30 minutes following MPG injection, rats in the sevoflurane and MPG ＋ sevoflurane groups breathed a mixed gas of 2.4% sevoflurane and 97.6% oxygen for 60 minutes. Rats in the sham operation, ischemia/reperfusion, and MPG groups breathed 100% pure oxygen for 60 minutes. （3） IschemiaJreperfusion： 24 hours after sevoflurane or pure oxygen preconditioning, middle cerebral artery occlusion models were established in the ischemia/reperfusion, sevoflurane, MPG ＋ sevoflurane, and MPG groups. Following 2 hours ischemia/6 hours and 24 hours reperfusion, the carotid artery was separated, but the middle cerebral artery was not occluded, in the sham operation group. MAIN OUTCOME MEASURES： In the ischemic hemisphere, PKC-ε translocation in the rat parietal cortex was measured by Wes

关键词： sevoflurane delayed neuroprotection reactive oxygen species cerebral ischemia/reperfusion injury protein kinase C-ε

Tetrahedral framework nucleic acid carrying angiogenic peptide prevents bisphosphonate-related osteonecrosis of the jaw by promoting angiogenesis

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International Journal of Oral Science 2022年第2期14卷 201-211页

作者： Dan Zhao Dexuan xiao Mengting Liu Jiajie Li Shuanglin Peng qing He Yue Sun Jingang xiao Yunfeng Lin State Key Laboratory of Oral Diseases&National Clinical Research Center for Oral Diseases&Department of Oral and Maxillofacial Surgery West China Hospital of StomatologySichuan UniversityChengduChina Department of Oral and Maxillofacial Surgery The Affiliated Stomatology Hospital of Southwest Medical UniversityLuzhouChina

The significant clinical feature of bisphosphonate-related osteonecrosis of the jaw(BRONJ)is the exposure of the necrotic *** clinical manifestations include jaw pain,swelling,abscess,and skin fistula,which seriously affect the patients’life,and there is no radical ***,new methods need to be found to prevent the occurrence of ***,a novel nanoparticle,t FNA-KLT,was successfully synthesized by us,in which the nanoparticle tetrahedral framework nucleic acid(tFNA)was used for carrying angiogenic peptide,KLT,and then further enhanced ***-KLT possessed the same characteristics as tFNA,such as simple synthesis,stable structure,and good ***,tFNA enhanced the stability of KLT and carried more KLT to interact with endothelial ***,it was confirmed that tFNA-KLT had the superior angiogenic ability to tFNA and KLT both in vitro and in *** we apply tFNA-KLT to the prevention of *** results showed that tFNA-KLT can effectively prevent the occurrence of BRONJ by accelerating *** summary,the prepared novel nanoparticle,tFNA-KLT,was firstly synthesized by *** was also firstly confirmed by us that tFNA-KLT significantly enhanced angiogenesis and can effectively prevent the occurrence of BRONJ by accelerating angiogenesis,thus providing a new avenue for the prevention of BRONJ and a new choice for therapeutic angiogenesis.

关键词： angiogenesis prevention swelling

Semisolid die forging process,microstructures and properties of AZ31 magnesium alloy mobile telephone shells

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International Journal of Minerals,Metallurgy and Materials 2011年第6期18卷 665-670页

作者： Ren-guo Guan Li-qing Chen Fu-rong Cao Zhan-yong Zhao Yong Ren College of Materials and Metallurgy Northeastern University Shenyang 110004 China State Key Lab of Rolling and Automation Northeastern University Shenyang 110004 China

A semisolid slurry of AZ31 magnesium alloy was prepared by vibrating wavelike sloping plate process,and the semisolid die forging process,microstructures,and properties of the magnesium alloy mobile telephone shell were *** semisolid forging process was performed on a YA32-315 four-column universal hydraulic *** microstructures were observed by optical microscopy,the hardness was analyzed with a model 450SVD Vickers hardometer,the mechanical properties was measured with a CMT5105 tensile test machine,and the fractograph of elongated specimens was observed by scanning electron microscopy （SEM）.The results reveal that with the increase of die forging force,the microstructures of the product become fine and dense.A lower preheating temperature and a longer dwell time are favorable to the formation of fine and dense *** optimum process conditions of preparing mobile telephone shells with excellent surface quality and microstructures are a die forging force of 2000 kN,a die preheating temperature of 250℃,and a dwell time of 240 *** solution treatment at 430℃ and aging at 220℃ for 8 h,the Vickers hardness is 61.7 and the ultimate tensile strength of the product is *** fractographs show the mixing mechanisms of quasi-cleavage fracture and ductile fracture.

关键词： magnesium alloys semisolid forging microstructure mechanical properties fracture

The synthesis and cytotoxic activity of novel organogermanium sesquioxides with anthraquinone or naphthalene moiety

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Chinese Chemical Letters 2007年第11期18卷 1347-1350页

作者： guo Qiang Shangguan Lun Liang Huang xiao Gang Qu Department of Pharmacy Jining Medical College Rizhao 276826 China Key Laboratory of Rare Earth Chemistry and Physics Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun 130022 China

Four novel organogermanium scsquioxidcs with anthraquinonc or naphthalene moiety were synthesized. The structures were characterized by IR NMR and elemental analysis, and their cytotoxicitics wcrc evaluated against human chronic mycloid leukemia K562 cell lines. The cytotoxicity could bc improved by the introduction of planar aromatic chromophorc moiety to the parent compound, Ge-132.

关键词： Organogermanium sesquioxide Synthesis Cytotoxicity

TBAF-catalyzed cyclization of 6-hydroxyhex-2-ynoates and 7-hydroxyhept-2-ynoates

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Chinese Chemical Letters 2011年第8期22卷 931-934页

作者： xiao qing Wang Ping Jing Jia Su Ping Liu Wei Yu State Key Laboratory of Applied Organic Chemistry Lanzhou University Lanzhou 730000 China

Tetrabutyl ammonium fluoride（TBAF） was found to be capable of catalyzing the intramolecular hydroalkoxylation of 6- hydroxyhex-2-ynoates and *** reaction could be used to prepare 2,5-substituted THF rings and 2,6- s... 详细信息

关键词： Tetrabutyl ammonium fluoride Et_3SiH Tetrahydrofuran Tetrahydropyran

CO_(2)浓度升高对农田生态系统水分利用效率的影响效应——基于气候箱控制性试验的Meta分析

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湖北农业科学 2024年第7期63卷 13-20页

作者：朱金瑞邹婧汝赵国庆河南大学民生学院河南开封475000 河南大学地理与环境学院河南开封475000

选取1985—2020年21篇与气候箱控制性试验有关的文献,利用Meta分析法研究CO_(2)浓度升高对农田生态系统水分利用效率(WUE)的影响。结果显示,在气候箱的控制下CO_(2)浓度升高对水分利用效率有正面影响,增加的比例为20%,对碳积累和蒸散发... 详细信息

选取1985—2020年21篇与气候箱控制性试验有关的文献,利用Meta分析法研究CO_(2)浓度升高对农田生态系统水分利用效率(WUE)的影响。结果显示,在气候箱的控制下CO_(2)浓度升高对水分利用效率有正面影响,增加的比例为20%,对碳积累和蒸散发分别有正面和负面的效应,影响的效应分别为34%和-4%,但都存在显著的异质性(P0.05)。异质性分析结果显示,CO_(2)浓度升高对WUE的影响效应在不同物种间具有显著的差异,其中对大豆和番茄的影响效应显著高于对小麦的影响效应(P<0.05)。此外,CO_(2)浓度升高对WUE的影响效应与光照强度、温度和土壤相对含水量都有显著的相关关系(P<0.05),其中与光照强度有负相关关系,与温度和土壤含水量有正相关关系;而与CO_(2)富集程度没有显著的相关关系。

关键词： CO_(2)浓度升高农田生态系统水分利用效率 Meta分析气候箱环境因子

Distribution and mechanism of gently dipping fractures subjected to river incision: A case study from Nujiang River, China

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Journal of Mountain Science 2018年第1期15卷 211-224页

作者： ZHU Lei HUANG Run-qiu YAN Ming CHEN guo-qing WEI Wei State Key Laboratory of Geohazard Prevention and Geoenvironment Protection Chengdu University of Technology College of architecture and urban planning Sichuan Agricultural University

Gently dipping fractures subjected to river incision are widely distributed on rock *** this paper,a rock slope on the Nujiang River(China)is investigated to study the role of gently dipping fractures in the rock slopes *** field surveys indicate that gentle fractures are concentrated in four main ***,the kinematics of the fracture system suggest that the genesis of these fractures can be synthesized into a progressive evolution *** model indicates that the joints begin with the formation of an array of en echelon cracks that are subjected to continued crack elongation and shearing before ultimately approaching one another and interacting to form a complex joint *** analysis is performed to reveal the mechanisms of this genesis,and three main fracture patterns are identified based on the slope stress and are classified with respect to the slope *** on the detail field investigations and the evolutionary history of the river valley,we propose that intermittent incision by the river was the main factor contributing to the concentrated distribution of gently dipping joints.

关键词： Joints Rock slope Distribution Fracture mode Genesis mechanism

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基于SPEI的中国干旱多尺度时空特征分析

节水灌溉 2024年第6期 111-120,127页

作者：高晴孙金伟赵晓雪吴立峰赵静谢恒星姚付启鲁东大学水利工程学院山东烟台264025 鲁东大学资源与环境工程学院山东烟台264025 南昌工程学院水利与生态工程学院南昌330099 长江水利委员会长江科学院武汉430012 渭南师范学院环境与生命科学学院陕西渭南714099

干旱作为影响社会经济发展的自然灾害之一,探究中国干旱时空变化特征,对干旱预防和策略制定具有重要意义。以1979-2020年中国7个区域的标准降水蒸散指数(SPEI)网格数据作为基础,应用干旱频率和强度指标,结合改进的Mann-Kendall检验(MMK... 详细信息

干旱作为影响社会经济发展的自然灾害之一,探究中国干旱时空变化特征,对干旱预防和策略制定具有重要意义。以1979-2020年中国7个区域的标准降水蒸散指数(SPEI)网格数据作为基础,应用干旱频率和强度指标,结合改进的Mann-Kendall检验(MMK)方法和滑动时间窗口法,分析不同时间尺度(1个月、3个月、6个月、12个月)下的中国干旱时空特征。结果表明:在空间上,青藏高原、内蒙草原地区、西北荒漠地区、东北湿润半湿润温带地区的干旱程度更为突出;干旱频率随SPEI时间尺度增大而减小,随干旱等级(SPEI-3、SPEI-6以及SPEI-12尺度)的增加而减少;中国空间趋势变化为西北荒漠地区、青藏高原、内蒙草原地区、华中华南湿润亚热带地区北部、华北湿润半湿润暖温带地区南部、东北湿润半湿润温带地区具有显著干旱化趋势,青藏高原和东北湿润半湿润温带地区均具有明显的干湿差异。在时间上,西北荒漠地区的SPEI-1~SPEI-12尺度、青藏高原的SPEI-1~SPEI-12尺度、内蒙草原地区的SPEI-1~SPEI-12尺度、东北湿润半湿润温带地区的SPEI-6和SPEI-12尺度、华中华南湿润亚热带地区SPEI-1、SPEI-3和SPEI-12尺度的干旱较为突出。研究结果可为中国干旱预防和影响评估提供一定参考依据。

关键词：干旱标准降水蒸散指数改进的Mann-Kendall检验滑动时间窗口多尺度时空特征