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质心分析法在小沙洲动态演化分析中的应用——以江苏辐射沙洲亮月沙为例 被引量:4
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作者 刘永学 张忍顺 李满春 《海洋通报》 CAS CSCD 北大核心 2004年第1期69-75,共7页
在遥感 (RS)、GIS 技术的支持下,根据 1973 —2000 年江苏盐城幅卫片,对江苏辐射沙洲外围小沙洲的动态趋势研究方法进行了探讨。在小沙洲轮廓边缘叠合比较的基础上,引入了形态学中质心的概念,并将之运用到辐射沙洲北部的亮月沙沙洲... 在遥感 (RS)、GIS 技术的支持下,根据 1973 —2000 年江苏盐城幅卫片,对江苏辐射沙洲外围小沙洲的动态趋势研究方法进行了探讨。在小沙洲轮廓边缘叠合比较的基础上,引入了形态学中质心的概念,并将之运用到辐射沙洲北部的亮月沙沙洲中。研究结果表明:( 1 ) 通过对外围小沙洲进行质心分析,可较好地揭示小沙洲的动态变化趋势。( 2 ) 亮月沙在整体南退的趋势下,同时还叠加了较为明显的东西摆动韵律,共可分为 6 个阶段。本文还对亮月沙动态变化趋势原因进行了讨论。 展开更多
关键词 质心分析 动态演化 亮月沙 江苏辐射沙洲
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上海地区正常成人X线头影的图形质心分析
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作者 龚宇华 魏亭亭 唐国华 《上海口腔医学》 CAS CSCD 北大核心 2012年第3期303-307,共5页
目的:建立上海地区正常成人图形质心分析法(centrographic analysis,CGA)的正常范围。方法:选取上海地区汉族正常成年人75名(男34名,女41名),年龄18~21岁。拍摄X线头颅侧位定位片,进行图形质心分析。并与高加索人的面部形态进行比... 目的:建立上海地区正常成人图形质心分析法(centrographic analysis,CGA)的正常范围。方法:选取上海地区汉族正常成年人75名(男34名,女41名),年龄18~21岁。拍摄X线头颅侧位定位片,进行图形质心分析。并与高加索人的面部形态进行比较。采用SAS9.2软件包对所得数据进行统计学分析。结果:获得上海地区正常成人图形质心分析法的正常范围,其中面部质心位于Ba-A线上;面上部质心位于质心平面上;面下部质心位于质心平面前方0.92~1.29mm;下切牙长轴经过下颌骨性联合部的后1/3;上切牙长轴经过眶点后方,并与下切牙形成良好的覆、覆盖关系;上下唇前缘位于外平面处。各测量指标在男女性别之间无显著差异(P>0.05)。结论:正常成人X线头影的图形质心分析存在地区和种族差异,与高加索人相比,上海人下颌位置相对靠前,上、下切牙唇倾,面下1/3软组织略突。 展开更多
关键词 图形质心分析 正常 头影测量 上海地区
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山地果园手扶式单履带运输车设计与试验 被引量:12
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作者 陈猛 张衍林 +2 位作者 李善军 孟亮 张雯 《华中农业大学学报》 CAS CSCD 北大核心 2019年第1期125-132,共8页
设计一种以单履带为行走机构的山地果园运输车,该山地果园运输车由单履带行走装置、车架、传动装置、动力系统等组成,其主体外形尺寸为1 540mm×600mm×815mm。根据整车质心分析和人机工程学确定车辆的结构和运动参数,并利用Cre... 设计一种以单履带为行走机构的山地果园运输车,该山地果园运输车由单履带行走装置、车架、传动装置、动力系统等组成,其主体外形尺寸为1 540mm×600mm×815mm。根据整车质心分析和人机工程学确定车辆的结构和运动参数,并利用Creo建立三维模型,计算出车辆的质心位置。根据车辆的质心位置分析车辆在横向坡面和纵向坡面的稳定性。对该山地果园运输车样机在满载情况下进行不同工作环境的测试,结果表明:设计的山地果园运输车的最大载荷为75kg,具备上10°纵向坡,下30°纵向坡以及通过20°横向坡面和通过各种复杂路面的能力。该运输车能够较好地满足山地果园横向运输要求。 展开更多
关键词 运输车 单履带 山地果园 质心分析 稳定性分析
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舰载红外干扰弹防御反舰导弹的战术运用研究 被引量:2
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作者 高东华 张祥林 《红外技术》 CSCD 北大核心 2005年第2期95-98,共4页
本文从舰载红外干扰弹防御反舰导弹的基本原理过程出发,分析了红外弹干扰质心死区形成的原因、影响其大小的主要因素以及作战使用中避免来袭导弹的威胁态势处于质心死区和减小质心死区的战术方法,提出了红外干扰弹防御反舰导弹作战使用... 本文从舰载红外干扰弹防御反舰导弹的基本原理过程出发,分析了红外弹干扰质心死区形成的原因、影响其大小的主要因素以及作战使用中避免来袭导弹的威胁态势处于质心死区和减小质心死区的战术方法,提出了红外干扰弹防御反舰导弹作战使用的战术决策原则和使用方法。 展开更多
关键词 红外干扰 防御反舰导弹 战术运用研究 红外对抗 质心死区分析
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Quality of life and palliative care needs of elderly patients with advanced heart failure 被引量:8
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作者 Helen YL Chan Doris SF Yu +2 位作者 Doris YP Leung Aileen WK Chan Elsie Hui 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2016年第5期420-424,共5页
Objective To examine the quality of life and palliative care needs of elderly patients with advanced heart failure (HF). Methods This was a correlation descriptive study conducted at a 650-bed sub-acute hospital. Pa... Objective To examine the quality of life and palliative care needs of elderly patients with advanced heart failure (HF). Methods This was a correlation descriptive study conducted at a 650-bed sub-acute hospital. Patients who were aged 65 or over, diagnosed with HF of New York Heart Association Class III or IV symptoms, and mentally sound were eligible to the study. The Edmonton Symptom Assessment Scale, the overall quality of life single item scale, and the McQill Quality of Life Questionnaire (MQoL), were used for measurement. Multi- ple regression analysis was performed to determine factors for predicting quality of life. Results A convenience sample of 112 patients was recruited. Their age was 81.5 ± 8.5 years. The three most distressing symptoms reported by the patients were tiredness (5.96 ± 2.78), drowsiness (5.47± 2.93), and shortness of breath (5.34 ± 2.96). Their mean overall quality of life single item scale score was 4.72 ± 2.06 out of 10. The mean MQoL physical subscale score was the lowest (4.20 ± 1.767), whereas their mean psychological subscale was the highest (7.14 ±2.39). However, in a multivariate analysis model, quality of life was significantly associated with existential wellbeing, physical wellbeing, psychological wellbeing and educational level. Conclusions The findings highlight that spiritual concerns are significant palliative care needs among elderly patients with advanced HF, in addition to symptom management. This is in line with the argument that palliative care that places great emphasis on holistic care should be integrated to the care of this group of patients. 展开更多
关键词 ASSESSMENT Heart failure Palliative care The elderly
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Short- and Long-term Therapeutic Efficacies of Intravenous Transplantation of Bone Marrow Stem Cells on Cardiac Function in Rats with Acute Myocardial Infarction:A Meta-analysis of Randomized Controlled Trials 被引量:2
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作者 Can Jiang Dong Zheng +3 位作者 Yun-lu Feng Jun Guo Hai-rui Li Ai-dong Zhang 《Chinese Medical Sciences Journal》 CAS CSCD 2016年第3期142-148,共7页
Objective To investigate the short- and long-term therapeutic efficacies of intravenous transplantation of bone marrow stem cells(MSCs) in rats with experimental myocardial infarction by metaanalysis.Methods Randomize... Objective To investigate the short- and long-term therapeutic efficacies of intravenous transplantation of bone marrow stem cells(MSCs) in rats with experimental myocardial infarction by metaanalysis.Methods Randomized controlled trials were systematically searched from Pub Med,Science Citation Index(SCI),Chinese journal full-text database(CJFD) up to December 2014.While the experimental groups(MSCs groups) were injected MSCs intravenously,the control groups were injected Delubecco's minimum essential medium(DMEM) or phosphate buffered saline(PBS).Subgroup analysis for each outcome measure was performed for the observing time point after the transplantation of MSCs.Weighted mean differences(WMD) and 95% confidence intervals(CI) were calculated for outcome parameters including ejection fraction(EF) and fractional shortening(FS),which were measured by echocardiogram after intravenous injection and analyzed by Rev Man 5.2 and STATA 12.0.Results Data from 9 studies(190 rats) were included in the meta-analysis.As compared to the control groups,the cardiac function of the experimental groups were not improved at day 7(EF:WMD=0.08,95%CI-1.32 to 1.16,P>0.01; FS:WMD=-0.12,95%CI-0.90 to 0.65,P>0.01) until at day 14 after MSCs' transplantation(EF:WMD=10.79,95%CI 9.16 to 12.42,P<0.01; FS:WMD=11.34,95%CI 10.44 to 12.23,P<0.01),and it lasted 4 weeks or more after transplantation of MSCs(EF:WMD=13.94,95%CI 12.24 to 15.64,P<0.01; FS:WMD=9.64,95%CI 7.98 to 11.31,P<0.01).Conclusion The therapeutic efficacies of MSCs in rats with myocardid infarction become increasing apparent as time advances since 2 weeks after injection. 展开更多
关键词 mesenchymal stem cells RATS myocardial infarction INTRAVENOUS
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Lipid profiling of mammalian cells with in situ matrix-assisted laser desorption ionization-mass spectrometry 被引量:1
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作者 ZHANG YanDong LI HaiFang +1 位作者 MA Yuan LIN JinMing 《Science China Chemistry》 SCIE EI CAS 2014年第3期442-446,1-3,共5页
The analysis of cellular lipids and phospholipids has been of continuously increasing research interest due to the importance of these molecules in psychological process.In this work,a mass spectrometry-based method f... The analysis of cellular lipids and phospholipids has been of continuously increasing research interest due to the importance of these molecules in psychological process.In this work,a mass spectrometry-based method for direct,in situ analysis of lipids in cells was reported.Mammalian cells were directly cultured on ITO-coated glass and then analyzed by matrix-assisted laser desorption ionization-mass spectrometry(MALDI-MS).The matrix application process was achieved by electrospray coating,which produced a homogenous layer of matrix crystal on the sample.The detection results and reproducibility are satisfactory.With this method,a profile of abundant membrane lipids is generated,which is characteristic of cell type.In conclusion,this in situ MALDI-MS cellular lipid analysis method provides a platform for sensitive and robust molecular profiling of mammalian cells. 展开更多
关键词 lipid profiling MALDI-MS linear discriminative analysis
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