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Using a Hidden Markov Model to Analyze the Flood-Season Rainfall Pattern and Its Temporal Variation over East China

Journal of Meteorological Research 2018年第3期32卷 410-420页

作者： Lianyi GUO Zhihong JIANG Weilin chen Key Laboratory of Meteorological Disaster of Ministry of Education Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science & Technology Joint International Research Laboratory of Climate and Environment Change Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science & Technology

The homogeneous hidden Markov model(HMM), a statistical pattern recognition method, is introduced in this paper. Based on the HMM, a 53-yr record of daily precipitation during the flood season(April-September) at 389 stations in East China during 1961-2013 is classified into six patterns: the South China(SC) pattern, the southern Yangtze River(SY) pattern, the Yangtze-Huai River(yh) pattern, the North China(NC) pattern, the overall wetter(OW) pattern, and the overall drier(OD) pattern. Features of the transition probability matrix of the first four patterns reveal that 1) the NC pattern is the most persistent, followed by the yh, and the SY is the least one; and 2) there exists a SY-SC-SY-yh-NC propagation process for the rain belt over East China during the flood season. The intraseasonal variability in the occurrence frequency of each pattern determines its start and end time. Furthermore,analysis of interdecadal variability in the occurrence frequency of each pattern in recent six decades has identified three obvious interdecadal variations for the SC, yh, and NC patterns in the mid-late 1970 s, the early 1990 s, and the late 1990 s. After 2000, the patterns concentrated in the southern region play a dominant role, and thus there maintains a "flooding in the south and drought in the north" rainfall distribution in eastern China. In summary, the HMM provides a unique approach for us to obtain both spatial distribution and temporal variation features of flood-season rainfall.

关键词： hidden Markov model(HMM) rainfall patterns flood season rain belt propagation interdecadal variability

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Fairness-Aware Harvested Energy Efficiency Algorithm for IRS-Aided Intelligent Sensor Networks with SWIPT

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Computer Modeling in Engineering & Sciences 2023年第12期137卷 2675-2691页

作者： Yingying chen Weiqiang Tan Shidang Li School of Geography Geomatics and PlanningJiangsu Normal UniversityXuzhou221116China School of Computer Science and Cyber Engineering Guangzhou UniversityGuangzhou510006China School of Physics and Electronic Engineering Jiangsu Normal UniversityXuzhou221116China

In this paper,a novel fairness-aware harvested energy efficiency-based green transmission scheme for wireless information and power transfer(SWIPT)aided sensor networks is developed for active beamforming of multiantenna transmitter and passive beamforming at intelligent reflecting surfaces(IRS).By optimizing the active beamformer assignment at the transmitter in conjunction with the passive beamformer assignment at the IRS,we aimtomaximize the minimumharvested energy efficiency among all the energy receivers(ER)where information receivers(IR)are bound to the signal-interference-noise-ratio(SINR)and the maximum transmitted power of the *** handle the non-convex problem,both semi-definite relaxation(SDR)and block coordinate descent technologies are ***,the original problem is transformed into two convex sub-problems which can be solved via semidefinite *** simulation results demonstrate that the IRS and energy beamformer settings in this paper provide greater system gain than the traditional experimental setting,thereby improving the fairness-aware harvested energy efficiency of the ER.

关键词： SWIPT intelligent reflecting surfaces fairness-aware harvested energy efficiency semi-definite relaxati

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颈动脉损伤大鼠新生内膜增生与局部平滑肌细胞的增殖

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中国组织工程研究与临床康复 2007年第2期11卷 222-225,T0001页

作者：陈凤英郭艳红高炜内蒙古医学院附属医院急救中心内蒙古自治区呼和浩特市010050 北京大学第三医院心内科北京市100083

目的:观察大鼠颈动脉损伤后高同型半胱氨酸血症对新生内膜形成和局部炎症因子单核细胞趋化因子1、细胞间黏附分子1表达及局部平滑肌细胞增殖的影响。方法:实验于2004-10/2005-02在北京大学第一临床医院心血管研究所完成。①Wistar雄性大... 详细信息

目的:观察大鼠颈动脉损伤后高同型半胱氨酸血症对新生内膜形成和局部炎症因子单核细胞趋化因子1、细胞间黏附分子1表达及局部平滑肌细胞增殖的影响。方法:实验于2004-10/2005-02在北京大学第一临床医院心血管研究所完成。①Wistar雄性大鼠50只,采用随机数字法分为蛋氨酸组:1g/(kg·d)L-蛋氨酸灌胃;对照组:饮用水灌胃,每组25只。4周后检测两组血浆同型半胱氨酸浓度,并行左颈动脉球囊拉伤,分别于3,7,14,28d取材,检测血管损伤后新生内膜增生和局部单核细胞趋化因子1、细胞间黏附分子1表达情况。结果:①两组大鼠血浆同型半胱氨酸浓度:蛋氨酸组血浆同型半胱氨酸浓度明显高于对照组[(106.19±19.75),(4.90±0.10)μmol/L]。②两组大鼠血管组织形态学观察结果:苏木精-伊红染色血管损伤后7d可见内膜增生,14,28d蛋氨酸组新生内膜增生厚度比对照组增加36%,33%;新生内膜面积增加41%,30%;内膜面积/中膜面积增加36%,21%;管腔面积减少47%,61%;两组间比较差异均有显著性,但中膜面积无显著性差别。蛋氨酸组14d血管内膜和中膜平滑肌细胞中增殖细胞核抗原阳性颗粒百分比是对照组的1.7倍和2.3倍[(84.40±9.05)%比(49.00±4.51)%,P<0.01;(53.30±5.25)%比(23.70±6.17)%,P<0.01]。未损伤的右颈总动脉两组血管内膜及中膜增殖细胞核抗原阳性颗粒数小于0.1%。蛋氨酸组血管损伤局部单核细胞趋化因子1、细胞间黏附分子1表达增强,单核细胞趋化因子1主要分布在新生内膜和中膜,细胞间黏附分子1主要分布在内皮下和新生内膜,3d,7d明显,持续28d。结论:高同型半胱氨酸血症上调血管损伤局部炎症因子单核细胞趋化因子1、细胞间黏附分子1表达,促使局部平滑肌细胞增殖,使新生内膜增生。

关键词：高半胱氨酸肌平滑炎症趋化因子类胞间粘附分子

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Transcranial magnetic stimulation for motor symptoms in Parkinson＇s disease

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中华物理医学与康复杂志 2015年第5期37卷 326-326页

作者： Chou yh Hickey PT Sundman M

BACKGROUND AND OBJECTIVE Parkinson''s disease (PD) is a progressive neurodegenerative disorder affecting approximately one percent of the population older than 60 years of age and four percent of those over the age of 80. Current treatments include medical therapy, as well as surgical techniques, including deep brain stimulation. During the past two decades, repetitive transcranial magnetic stimulation (rTMS) has been examined as a possible treatment for PD. This meta-analysis was designed to better understand the effects of (rTMS) on the motor symptoms of *** A literature search was conducted using multiple databases through June 30, 2014. Studies included those focused on PD and rTMS which were sham controlled and randomized. Motor symptoms were measured using the motor examination of the Unified Parkinson''s Disease Rating Scale (UPDRS).RESULTS Twenty studies were included, for a total of 470 patients. The effect size of rTMS on the UPDRS was 0.46, a medium effect size in reducing motor symptoms (P<0.001). The subgroup analysis found no significant differences in effect size between rTMS sites and between high-frequency and low-frequency rTMS. However, the treatment effects of high-frequency rTMS that targeted the primary motor cortex, as well as low frequency rTMS applied over other frontal regions, were both significant (P<0.001 andP=0.008, respectively). A meta-regression analysis revealed that a greater number of pulses per session or across sessions was associated with a greater treatment *** This systematic review and meta-analysis suggests that repetitive transcranial magnetic stimulation can improve motor symptoms in Parkinson''s disease, with key modulators of effect including stimulation site, frequency and number of pulses.

关键词：经颅磁刺激帕金森氏症症状运动神经退行性疾病药物治疗帕金森病 rTMS

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血管内皮生长因子与运动的相关性

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中国组织工程研究与临床康复 2007年第23期11卷 4602-4605页

作者：葛运华成都体育学院研究生部四川省成都市610041

目的:血管内皮生长因子是一种广泛存在于机体组织的细胞因子,与运动密切相关,是近来运动人体科学界和运动医学界研究的焦点。对近来血管内皮生长因子与运动的相关研究进行综述,以能够找到提高训练质量乃至运动水平的方法。资料来源:应... 详细信息

目的:血管内皮生长因子是一种广泛存在于机体组织的细胞因子,与运动密切相关,是近来运动人体科学界和运动医学界研究的焦点。对近来血管内皮生长因子与运动的相关研究进行综述,以能够找到提高训练质量乃至运动水平的方法。资料来源:应用计算机检索***1996-01/2006-12的相关文章,并根据相关的参考文献检索了部分文章,检索词“vascular endothelial growth factor,exercise”,限定语言种类为English;同时计算机检索中国知识资源总库1996-01/2006-12的相关文献,限定语言种类为中文,检索词“血管内皮生长因子,运动”。资料选择:纳入条件:①随机对照试验研究。②试验包括对照组和干预组。同时排除综述和重复的研究。资料提炼:共找到相关研究47篇,排除17篇,30篇符合标准。通过30个实验对运动中血管内皮生长因子在机体中的表达、作用及含量和动态变化进行了相关的分析和研究。资料综合:①血管内皮生长因子与运动的关系密切相关,现在仍然是运动医学界的研究焦点之一,研究的方向为运动对机体血管内皮生长因子的影响,目的是发现运动对机体的影响。②不同的运动方式对机体的血管内皮生长因子的表达不同,目前采用的训练方式多为极限运动或运动与其他因素相结合,如低压强+运动。③观察部位多集中在大脑、肌肉、心血管、血液等,不同部位的表达不同。④运动对血管内皮生长因子表达有动态变化的规律。结论:血管内皮生长因子与运动的关系密切相关,不同的运动方式会造成血管内皮生长因子在机体不同部位不同表达。运动对血管内皮生长因子表达的影响呈现出规律性。

关键词：受体血管内皮生长因子运动综述文献

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Association of polymorphisms in the vascular endothelial growth factor gene and its serum levels with diabetic retinopathy in Chinese patients with type 2 diabetes： A cross-sectional study

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Chinese Medical Journal 2014年第4期127卷 651-657页

作者： Fan XH Wu QH Li Y Hao yh Ning N Kang Z Cui Y Liu RH Department of Social Medicine School of Health ManagementHarbin Medical University Harbin Heilongjiang 150081 China Second Hospital of Harbin Heilongjiang 150001 China Second Hospital of Harbin Heilongjiang i50001 China Wenhua Community Clinics Qiqihar Heilongjiang 161005 China

Background Vascular endothelial growth factor （VEGF） is a major mediator of angiogenesis,and plays a key role in the pathogenesis of diabetic retinopathy （DR）.This study was designed to identify the possible role of VEGF gene polymorphisms in the development of DR in type 2 diabetic patients in Chinese and clarify the relationship between VEGF serum levels and the risk of *** This cross-sectional study included 1 040 Chinese subjects with type 2 diabetes *** were 372 patients diagnosed with DR in the case group and 668 patients without DR in the control *** from each patient was analyzed for VEGF polymorphisms of-2578A/C （rs699947）,-1154G/A （rs1570360）,-460C/T （rs833061）,＋405C/G （rs2010963）,and ＋936C/T （rs3025039） using MassARRAY compact *** VEGF serum levels were quantified by enzyme-linked immunosorbent assay （ELISA）.Results No evidence of association was observed between-2578 A/C （rs699947）,＋405C/G （rs2010963）,＋936C/T （rs3025039）,and DR risk under stringent Bonferroni＆#39;s ***,VEGF serum levels were significantly higher in DR patients than those of control *** genetic variation of VEGF polymorphisms influenced VEGF serum levels; subjects carrying the VEGF-2578 C/C （rs699947） genotype had greater VEGF serum levels than those carrying the C/A genotype and VEGF serum levels were significantly higher in CC genotype of the ＋405C/G （rs2010963） compared with those of the other *** The data did not suggest significant association between the VEGF polymorphisms and DR risk under stringent Bonferroni＆#39;s ***,our study indicated that DR patients have higher VEGF levels than diabetic patients without retinopathy,and-2578A/C （rs699947） and ＋405C/G （rs2010963） may be important factors in determining serum VEGF levels.

关键词： vascular endothelial growth factor polymorphism genetics diabetic retinopathy

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髋关节置换术后股骨假体周围骨密度的变化

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中国组织工程研究与临床康复 2007年第41期11卷 8337-8339页

作者：朱燕辉上海交通大学医学院附属第九人民医院骨科上海市200011

目的:总结国内外全髋关节置换术后股骨假体周围骨密度变化的研究,为全髋关节置换术后假体周围骨溶解的早期发现提供依据。资料来源:检索Medline1980-01/2006-04和Embase1980-10/2006-08期间的相关文章,检索词"Total Hip Arthroplasty,bo... 详细信息

目的:总结国内外全髋关节置换术后股骨假体周围骨密度变化的研究,为全髋关节置换术后假体周围骨溶解的早期发现提供依据。资料来源:检索Medline1980-01/2006-04和Embase1980-10/2006-08期间的相关文章,检索词"Total Hip Arthroplasty,bone loss",并限定文章语言种类为English。同时检索万方数据库1990-01/2001-04期间的相关文章,限定文章语言种类为中文,检索词"全髋置换术,假体周围,骨密度"。资料选择:纳入标准是与全髋置换术后假体周围骨密度相关的文章,以临床研究类文章为主,同时包括综述性文章。资料提炼:共收集相关文献56篇,按上述标准纳入30篇,其余文献均被排除。资料综合:全髋置换术股骨假体有两种固定方式:骨水泥固定型与非骨水泥固定型。两种类型虽然固定方式不同,但术后假体周围均存在骨量丢失,应用双能X线吸收测定法能够早期检测出假体周围骨量的丢失。结论:双能X线吸收测定法逐渐成为定量监测假体周围骨量丢失的重要手段,术后连续性检测假体周围骨密度对于早期发现假体松动有重要意义。

关键词：髋关节股骨假体骨密度

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Risk of complex regional pain syndrome after distal radial fracture

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中华物理医学与康复杂志 2015年第3期37卷 175-175页

作者： Roh yh Lee BK Noh JH

BACKGROUND AND OBJECTIVE The most common type of fracture in the upper extremity is the distal radial *** fractares carry a high risk of creating complex regional pain syndrome,type I(CRPS-1).This study was designed to further understand the risk of CRPS-1 among patients with these *** Subjects were 477 patients with a distal radial fracture,treated surgically between July of 2010 and April of *** patients were assessed for symptoms of CRPS-1 at six,1 2 and 24 weeks after *** follow-up,42 patients with were diagnosed with

关键词：复杂区域综合征骨折风险远端桡骨疼痛

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桑叶黄酮对α-糖苷酶活性的影响

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中国组织工程研究与临床康复 2007年第21期11卷 4191-4193页

作者：薛长勇刘英华张荣欣郑子新张月红景洪江张永欧阳红 Eugene chen 解放军总医院营养科北京市100853 美国密西根大学心血管中心

目的:观察桑叶提取物桑叶黄酮对α-糖苷酶活性的影响及其对小鼠餐后血糖的影响。方法:实验于2005-07/10在解放军总医院营养科实验室和动物中心实验室进行。在体外实验中,设立空白组、阿卡波糖不同含量组和桑叶黄酮不同含量组(终浓度为0,... 详细信息

目的:观察桑叶提取物桑叶黄酮对α-糖苷酶活性的影响及其对小鼠餐后血糖的影响。方法:实验于2005-07/10在解放军总医院营养科实验室和动物中心实验室进行。在体外实验中,设立空白组、阿卡波糖不同含量组和桑叶黄酮不同含量组(终浓度为0,7.81,15.63,31.25,62.50,125.00,250.00mg/L)。以阿卡波糖为阳性对照、以无抑制剂时α-糖苷酶活性为100%,检测桑叶总黄酮、HP-20树脂吸附黄酮和非吸附黄酮对α-糖苷酶活性的影响。在体内实验中,将昆明小鼠40只,按血糖水平随机分为4组,即淀粉组、淀粉+HP-20吸附黄酮组、蔗糖组、蔗糖+HP-20吸附黄酮组,每组10只,分别给予淀粉(3g/kg)、淀粉(3g/kg)+HP-20吸附黄酮(500mg/kg)、蔗糖(1.5g/kg)以及蔗糖(1.5g/kg)+HP-20吸附黄酮(500mg/kg)。检测并比较1h、2h血糖水平。结果:①当阿卡波糖、桑叶总黄酮含量为0,7.81,15.63,31.25,62.50,125.00,250.00mg/L时,α-糖苷酶IC50=70.43,82.11mg/L。②在相同HP-20树脂吸附黄酮浓度条件下,α-糖苷酶活性分别为100.00%,94.61%,84.90%,63.04%,26.27%,11.37%和6.76%,其IC50=59.25mg/L;在相同HP-20树脂非吸附黄酮浓度条件下,α-糖苷酶活性分别为100.00%,90.55%,88.55%,85.91%,78.00%,69.91%和56.36%,其IC50=82.86mg/L。③在给予淀粉的糖耐量实验中,HP-20树脂吸附黄酮组1h后血糖水平明显低于其淀粉对照组[(9.06±1.10),(11.13±1.45)mmol/L,t=2.1009,P=0.00209];在给予蔗糖的糖耐量实验中,HP-20树脂吸附黄酮组1h后血糖水平也明显低于其蔗糖对照组[(9.88±1.01),(12.75±1.17)mmol/L,t=2.1009,P=0.000014]。结论:体外实验提示桑叶总黄酮、HP-20树脂吸附和非吸附黄酮均具有抑制α-糖苷酶活性的作用,其中HP-20吸附黄酮对糖苷酶的抑制作用强于阿卡波糖;体内实验也证实HP-20吸附黄酮能够抑制给予淀粉和蔗糖后1h血糖的升高。

关键词：桑叶黄酮 α甘露糖苷酶树脂类,合成

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Preparation,characterization and properties of aminoethyl chitin hydrogels

Preparation,characterization and properties of aminoethyl ch...

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2012年湖北生物产业发展高端论坛暨湖北省生物工程学会2012年度学术交流会

作者： He GH Wang Z Zheng H Yin yh Xiong X School of Chemical Engineering Wuhan University of Technology

Aminoethyl chitin(AEC) was synthesized by grafting 2-chlorethylamine hydrochloride to chitin molecule,and characterized by FT-IR and H *** product had a better performance in the solubility with amino amount increasing from 25.52%to 110.8%by measuring the transmittance of AEC ***-linked hydrogels were synthesized by forming Schiff base among AEC chains using glutaraldehyde(GA),and characterized by *** circular of elliptical macropores in hydrogels were observed by Scanning Electron Microscopy(SEM). The swelling performance of AEC hydrogel showed that it was sensitive to environmental *** addition,the equilibrium swelling ratio(SR) changed with amino amount,declined with the increase of cross-linking degree and increased with the increase of AEC *** antibacterial activity of obtained hydrogels was studied against Staphylococcus aureus(***) via optical density(OD) *** reduction rate(BRR) showed the gels exhibited antibacterial activity in a certain period,demonstrated that these chitin-based hydrogels were promising biomaterials.

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