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经纬度梯度上狗牙根半致死温度及耐寒性评价

中国草地学报 2022年第3期44卷 49-57页

作者：陈鸣晖冯渝茜金诗璇范吉标严学兵扬州大学动物科学与技术学院江苏扬州225009

为理解狗牙根[Cynodon dactylon(L.)Pers.]耐寒性与地理分布之间的关系,采用电导法结合Logistic方程对不同经纬度上28个地区的野生狗牙根进行抗寒性评价。结果表明,纬度梯度上狗牙根的半致死温度(LT_(50))范围是-8.70~-0.70℃,仙1抗寒... 详细信息

为理解狗牙根[Cynodon dactylon(L.)Pers.]耐寒性与地理分布之间的关系,采用电导法结合Logistic方程对不同经纬度上28个地区的野生狗牙根进行抗寒性评价。结果表明,纬度梯度上狗牙根的半致死温度(LT_(50))范围是-8.70~-0.70℃,仙1抗寒性最强;经度梯度上是-9.91~-2.40℃,郯1抗寒性最强。狗牙根的耐寒性与纬度有非线性关系,中纬度的狗牙根耐寒性显著小于高纬度和低纬度。狗牙根的耐寒性也与年降水量呈极显著正相关。结果表明,经度梯度的郯1、单1和潼3以及纬度梯度的仙1、仙2和郑3等材料具有耐寒品种开发潜力。

关键词：狗牙根相对电导率耐寒性 Logistic方程经纬度

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SnO高压结构稳定性和电学性能研究

光谱学与光谱分析 2025年第1期45卷 82-87页

作者：刘涛黄宇轩高金金王世霞上海理工大学材料与化学学院上海200093

近年来氧化亚锡(SnO)在光、电等方面的应用日益广泛,为了拓宽SnO的应用范围,采用拉曼光谱原位测试和第一性原理计算对高压条件下SnO的结构性能和电子性质进行研究。SnO表征结果:扫描电子显微镜结果显示,所选取SnO样品为具有横向尺寸的... 详细信息

近年来氧化亚锡(SnO)在光、电等方面的应用日益广泛,为了拓宽SnO的应用范围,采用拉曼光谱原位测试和第一性原理计算对高压条件下SnO的结构性能和电子性质进行研究。SnO表征结果:扫描电子显微镜结果显示,所选取SnO样品为具有横向尺寸的片状堆叠,整体呈花状;X射线衍射图谱表明,SnO样品在常温常压下晶体结构为四方晶系结构(空间群P4/nmm)。采用Mao-Bell型金刚石压腔结合原位拉曼光谱探究了SnO样品在高压下的结构性能变化,结果显示:SnO在常压有四种拉曼振动模式(A_(1g)、B_(1g)、E_(1g)和E_(2g)),分别位于211、350、113和460 cm^(-1)波数附近,其中113和211 cm^(-1)为SnO拉曼特征峰。随SnO样品体系加压至12.5 GPa,压力使Sn分子间和原子间距不断减小,导致Sn-O键长缩短,当原子发生伸缩振动时,缩短的键长使得键能增大,因此活性拉曼振动模(E_(1g)和A_(1g))均向高频方向移动;随着体系压力的继续增大,晶格发生畸变进而使得非弹性散射强度降低,峰型宽化;当加压至8 GPa时,125和216 cm^(-1)附近振动模峰急剧减小;加压至10 GPa时两个特征峰完全消失,在非静水压环境下8~10 GPa时该物质发生了非晶化;当体系加压至12.5 GPa时,谱图中仍未出现新峰,表明高压下非晶化状态稳定。随后体系进行卸压,卸压至3 GPa后SnO的E_(1g)和A_(1g)模重新出现表明样品恢复低压下的晶体结构,卸至常压特征峰强度明显分别为110和209 cm^(-1)处与加压前吻合,证明了SnO高压相变行为具有可逆性。为进一步了解压力对SnO电学性能影响,使用第一性原理方法计算了SnO在常压和实验非晶化压力(8 GPa)下的电子性质,通过非晶化前后SnO的带隙宽度变化,探究压力对SnO导电性能的影响。结果显示,在常压下SnO为具有0.43 eV带隙的间接带隙半导体,在费米能级附近态密度没有发生重叠,8 GPa时SnO显示金属性质,由于SnO O-p、Sn-s和Sn-p轨道的态密度在费米能级处重叠,导致带隙的闭合,材料发生金属化。研究结果表明SnO高压下可能产生非晶化及压力所导致的非晶化行为可逆,同时高压导致SnO发生半导体到金属的转变,拓展了SnO高压结构和电学性质的探究,为SnO高压下的应用提供进一步帮助。

关键词： SnO 拉曼光谱金刚石压腔第一性原理电子性质

A matrix metalloproteinase-responsive hydrogel system controls angiogenic peptide release for repair of cerebral ischemia/reperfusion injury

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Neural Regeneration Research 2025年第2期20卷 503-517页

作者： Qi Liu Jianye Xie Runxue Zhou jin Deng Weihong Nie Shuwei Sun Haiping Wang Chunying shi Department of Human Anatomy Histology and EmbryologySchool of Basic MedicineQingdao UniversityQingdaoShandong ProvinceChina Department of Neurology The Affiliated Hospital of Qingdao UniversityQingdaoShandong ProvinceChina Department of General Practice The Affiliated Hospital of Qingdao UniversityQingdaoShandong ProvinceChina

Vascular endothelial growth factor and its mimic peptide KLTWQELYQLKYKGI(QK)are widely used as the most potent angiogenic factors for the treatment of multiple ischemic ***,conventional topical drug delivery often results in a burst release of the drug,leading to transient retention(inefficacy)and undesirable diffusion(toxicity)in ***,a drug delivery system that responds to changes in the microenvironment of tissue regeneration and controls vascular endothelial growth factor release is crucial to improve the treatment of ischemic *** metalloproteinase-2(MMP-2)is gradually upregulated after cerebral ***,vascular endothelial growth factor mimic peptide QK was self-assembled with MMP-2-cleaved peptide PLGLAG(TIMP)and customizable peptide amphiphilic(PA)molecules to construct nanofiber hydrogel ***-TIMP-QK was found to control the delivery of QK by MMP-2 upregulation after cerebral ischemia/reperfusion and had a similar biological activity with vascular endothelial growth factor in *** results indicated that PA-TIMP-QK promoted neuronal survival,restored local blood circulation,reduced blood-brain barrier permeability,and restored motor *** findings suggest that the self-assembling nanofiber hydrogel PA-TIMP-QK may provide an intelligent drug delivery system that responds to the microenvironment and promotes regeneration and repair after cerebral ischemia/reperfusion injury.

关键词： angiogenesis biomaterial blood-brain barrier cerebral ischemia/reperfusion injury control release drug delivery inflammation QK peptides matrix metalloproteinase-2 neuroprotection self-assembling nanofiber hydrogel

经翼点入路显微手术治疗前循环脑动脉瘤的临床效果

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中外医学研究 2017年第2期15卷 11-12页

作者：周金旋施辉秋杨丛汕尾市第二人民医院汕尾逸挥基金医院广东汕尾516600

目的:研究经翼点入路显微手术治疗前循环脑动脉瘤的临床效果。方法:将笔者所在医院神经外科2014年2月-2015年2月收治的50例前循环脑动脉瘤患者分为对照组(25例)与试验组(25例)。对照组采取血管内栓塞术治疗,试验组采用经翼点入路显微手... 详细信息

目的:研究经翼点入路显微手术治疗前循环脑动脉瘤的临床效果。方法:将笔者所在医院神经外科2014年2月-2015年2月收治的50例前循环脑动脉瘤患者分为对照组(25例)与试验组(25例)。对照组采取血管内栓塞术治疗,试验组采用经翼点入路显微手术治疗。评估两组疗效并对比并发症发生率。结果:试验组患者治疗总有效率为92.0%,较对照组的68.0%更高,差异有统计学意义(P<0.05)。试验组术后并发症发生率4.0%,明显低于对照组的20.0%(P<0.05)。结论:翼点入路手术方案治疗大脑前循环动脉瘤的效果较血管内栓塞术更佳,但应注意合理选择手术时机、手术入路,确保术中显微操作精确性,并做好并发症防治及围术期管理工作。

关键词：显微神经外科手术大脑前循环翼点入路动脉瘤

Reveal training performance mystery between Tensor Flow and PyTorch in the single GPU environment

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Science China(Information Sciences) 2022年第1期65卷 147-163页

作者： Hulin DAI xuan PENG xuanhua shi Ligang HE Qian XIONG Hai jin National Engineering Research Center for Big Data Technology and System Service Computing Technology and System LabSchool of Computer Science and Technology Huazhong University of Science and Technology Department of Computer Science University of Warwick

Deep learning has gained tremendous success in various fields while training deep neural networks(DNNs) is very compute-intensive, which results in numerous deep learning frameworks that aim to offer better usability and higher performance to deep learning practitioners. Tensor Flow and Py Torch are the two most popular frameworks. Tensor Flow is more promising within the industry context, while Py Torch is more appealing in academia. However, these two frameworks differ much owing to the opposite design philosophy:static vs dynamic computation graph. Tensor Flow is regarded as being more performance-friendly as it has more opportunities to perform optimizations with the full view of the computation graph. However, there are also claims that Py Torch is faster than Tensor Flow sometimes, which confuses the end-users on the choice between them. In this paper, we carry out the analytical and experimental analysis to unravel the mystery of comparison in training speed on single-GPU between Tensor Flow and Py Torch. To ensure that our investigation is as comprehensive as possible, we carefully select seven popular neural networks, which cover computer vision, speech recognition, and natural language processing(NLP). The contributions of this work are two-fold. First, we conduct the detailed benchmarking experiments on Tensor Flow and Py Torch and analyze the reasons for their performance difference. This work provides the guidance for the end-users to choose between these two frameworks. Second, we identify some key factors that affect the performance,which can direct the end-users to write their models more efficiently.

关键词： deep learning performance comparison TensorFlow PyTorch

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福建漳州地区高职学生患龋状况及相关因素的调查研究

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临床口腔医学杂志 2017年第1期33卷 10-13页

作者：魏婷婷彭好津吴天昊傅小彬林荣金陈瑄瑄史建陆漳州卫生职业学院福建漳州363000 海南省人民医院口腔科海南海口570311 漳州卫生职业学院附属口腔医院福建漳州363000 漳州市疾病预防控制中心宣教科福建漳州363000 厦门市口腔医院福建厦门361000

目的:调查漳州地区高职学生龋病流行情况及相关因素分析。方法:调查福建漳州地区3所高职院校5327名19岁学生的患龋情况,并通过问卷了解学生饮食习惯、口腔卫生行为习惯及口腔健康知识态度。结果:5327名调查对象的患龋率51.15%,龋均2.41... 详细信息

目的:调查漳州地区高职学生龋病流行情况及相关因素分析。方法:调查福建漳州地区3所高职院校5327名19岁学生的患龋情况,并通过问卷了解学生饮食习惯、口腔卫生行为习惯及口腔健康知识态度。结果:5327名调查对象的患龋率51.15%,龋均2.41±3.19,男女对比差异无统计学意义(P>0.05)。与对照组相比,病例组甜食摄入频繁,口腔卫生行为习惯较差、口腔知识较匮乏,但态度较端正(P<0.05)。结论:福建漳州地区高职学生患龋率高,应加强口腔知识宣教,提高口腔保健意识,降低患龋率,提高群体口腔健康水平。

关键词：高职学生龋病行为知识态度

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丹酚酸膜缓控释滴丸的制备及其体外释放度

沈阳药科大学学报 2010年第7期27卷 525-529页

作者：刘伟星吴婵娟王锦旋石春勤吴先玉高崇凯广东药学院药剂教研室广东广州510006

目的研究丹酚酸缓释滴丸的制备方法。方法通过固体分散技术,以聚乙二醇6000(polyeth-ylene-glycol 6000,PEG-6000)和聚乙二醇400(polyethylene-glycol 400,PEG-400)为滴丸基质制备滴丸丸心,以乙基纤维素(ethyl cellulose,EC)、丙烯酸树脂高渗(eudragit RL100)、丙烯树脂低渗(eud-ragit RS100)、邻苯二甲酸二乙酯(diethyl phthalate,DEP)为包衣材料,体积分数为95%的乙醇溶液为包衣溶剂进行包衣,利用均匀设计优化处方,制得具有良好缓释效果丹酚酸缓释滴丸。结果以PEG-6000和PEG-400为固体分散辅料可制得外观圆整,质地均匀的丹酚酸滴丸,包衣处方中以乙基纤维素3.0 g、丙烯酸树脂RL100和RS100 1.0 g、邻苯二甲酸二乙酯2.5 mL、体积分数为95%的乙醇溶液100 mL、包衣增质量分数为3%能达到最佳的释放效果。结论所制备的丹酚酸缓释滴丸具有良好的释放效果。

关键词：丹酚酸滴丸包衣

Deriving a minimum set of viewpoints for maximum coverage over any given digital elevation model data

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International Journal of Digital Earth 2016年第12期9卷 1153-1167页

作者： xuan shi Bowei Xue Department of Geoscience University of ArkansasFayettevilleARUSA

This paper introduces how to automatically derive a minimum set of viewpoints for maximum coverage over a large scale of digital terrain *** is a typical data and computation-intensive research covering a series of geocomputation tasks that have not been implemented efficiently or optimally in prior *** paper introduces a three-step computational solution to resolve the *** any given digital elevation model(DEM)data,automatic generation of control viewpoints is the first step through map algebra calculation and hydrological modeling *** each viewpoint,the viewshed calculation then has to be *** combined viewshed derived from the viewshed of all viewpoints establishes the maximum viewshed coverage of the given ***,detecting the minimum set of viewpoints for the maximum coverage is a Non-deterministic Polynomial-time hard *** outcome of the computation has broader societal impacts since the research questions and solutions can be adapted into realworld application and decision-making practice,such as the distribution,optimization and management of telecommunication infrastructure and wildfire observation towers,and military tactics and operations dependent upon landscape and terrain features.

关键词： Minimum set maximum coverage viewshed digital terrain optimization

Parallelizing maximum likelihood classification on computer cluster and graphics processing unit for supervised image classification

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International Journal of Digital Earth 2017年第7期10卷 737-748页

作者： xuan shi Bowei Xue Department of Geosciences University of ArkansasFayettevilleARUSA

Supervised image classification has been widely utilized in a variety of remote sensing *** large volume of satellite imagery data and aerial photos are increasingly available,high-performance image processing solutions are required to handle large scale of *** paper introduces how maximum likelihood classification approach is parallelized for implementation on a computer cluster and a graphics processing unit to achieve high performance when processing big imagery *** solution is scalable and satisfies the need of change detection,object identification,and exploratory analysis on large-scale high-resolution imagery data in remote sensing applications.

关键词： Maximum likelihood classification supervised classification parallel computing graphics processing unit