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Analysis of Porter’s Five Forces Competitive Model in China’s Property Rights Trading Market
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作者 Weinong Wang 《Proceedings of Business and Economic Studies》 2024年第3期206-211,共6页
In recent years,China’s property rights trading market has been extremely competitive,but there are also new contradictions and challenges.This paper aims to analyze the external and internal competitive market of th... In recent years,China’s property rights trading market has been extremely competitive,but there are also new contradictions and challenges.This paper aims to analyze the external and internal competitive market of the property rights market through Porter’s five forces competition model,then find out the problems and defects in the development,thereby promoting the better development and progress of China’s property rights trading market. 展开更多
关键词 porters five forces competitive model Market optimization Innovative development
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甘肃积石山 M_(s)6.2级地震的震害特征与启示 被引量:2
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作者 王丽丽 王兰民 +5 位作者 卢育霞 许世阳 夏晓雨 盖海龙 池佩红 郭梅 《世界地震工程》 北大核心 2024年第1期58-71,共14页
2023年12月18日,甘肃省临夏回族自治州积石山保安族东乡族撒拉族自治县(35.70°N,102.79°E)发生了6.2级地震,震中烈度为VIII度。地震发生后,通过实地烈度评估与科学考察,对震区VI~VIII度区不同建(构)筑物与生命线工程的震害特... 2023年12月18日,甘肃省临夏回族自治州积石山保安族东乡族撒拉族自治县(35.70°N,102.79°E)发生了6.2级地震,震中烈度为VIII度。地震发生后,通过实地烈度评估与科学考察,对震区VI~VIII度区不同建(构)筑物与生命线工程的震害特点进行了统计分析;从抗震设计与施工管理、场地放大效应与地震次生灾害对建筑结构抗震性能的影响等角度,提出了此次地震的震害启示。结果表明:1)严重破坏和毁坏的建筑结构主要集中在老旧的土木结构、砖木结构和无设防或设防不规范的砖混结构。2)造成建筑结构破坏的主要原因是少量自建房抗震设计和施工的不规范、场地放大效应和地震次生灾害。3)优化和改良生土砌筑材料,改进纵横墙间的拉结措施,强化结构整体性是提高土木结构抗震的有效方法;普及“上下圈梁与构造柱”等基本抗震设防措施,规范水泥砂浆强度,提升农村工匠的施工水平,可有效提高砌体结构的整体性,避免房屋出现整体性垮塌;室内洗手间的墙体应该与房顶、纵横墙间建立有效联接,提高结构的抗震性能。4)孤突斜坡、河流高阶地与岸边为抗震不利地带。当建造用地极为匮乏,不得不选址在这些场地之上时,应该综合考虑场地的地形地貌特征、岩土体物理力学特性、水文地质条件、抗震设防目标、建筑结构类型等影响因素,做好地震灾害风险评估,根据评估结果进行科学设防。灾后重建过程中,应由政府统一规划选址、统一设计,规范施工。 展开更多
关键词 积石山6.2级地震 震害调查 场地放大效应 黄土液化流滑 震害特征
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Lactoferrin modification of berberine nanoliposomes enhances the neuroprotective effects in a mouse model of Alzheimer’s disease 被引量:3
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作者 Lin Wang Bi-Qiang Zhou +5 位作者 Ying-Hong Li Qian-Qian Jiang Wei-Hong Cong Ke-Ji Chen Xiao-Min Wen Zheng-Zhi Wu 《Neural Regeneration Research》 SCIE CAS CSCD 2023年第1期226-232,共7页
Previous studies have shown that berberine has neuroprotective effects against Alzheimer’s disease,including antagonizing tau phosphorylation,and inhibiting acetylcholinesterase activity and neural cell apoptosis.How... Previous studies have shown that berberine has neuroprotective effects against Alzheimer’s disease,including antagonizing tau phosphorylation,and inhibiting acetylcholinesterase activity and neural cell apoptosis.However,its low bioavailability and adverse reactions with conventional administration limit its clinical application.In this study,we prepared berberine nanoliposomes using liposomes characterized by low toxicity,high entrapment efficiency,and biodegradability,and modified them with lactoferrin.Lactoferrin-modified berberine nanoliposomes had uniform particle size and high entrapment efficiency.We used the lactoferrin-modified berberine nanoliposomes to treat a mouse model of Alzheimer’s disease established by injection of amyloid-beta 1-42 into the lateral ventricle.Lactoferrin-modified berberine nanoliposomes inhibited acetylcholinesterase activity and apoptosis in the hippocampus,reduced tau over-phosphorylation in the cerebral cortex,and improved mouse behavior.These findings suggest that modification with lactoferrin can enhance the neuroprotective effects of berberine nanoliposomes in Alzheimer’s disease. 展开更多
关键词 ACETYLCHOLINEsTERAsE Alzheimer’s disease apoptosis BERBERINE brain targeting LACTOFERRIN NANOLIPOsOMEs neuroprotective effects Tau phosphorylation
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A novel binary effective medium model to describe the prepeak stressstrain relationship of combined bodies of rock-like material and rock 被引量:1
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作者 Tienan Wang Yue Zhai +2 位作者 Huan Gao Yubai Li Ruifeng Zhao 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2023年第5期601-616,共16页
Combined bodies of rock-like material and rock are widely encountered in geotechnical engineering,such as tunnels and mines.The existing theoretical models describing the stress-strain relationship of a combined body ... Combined bodies of rock-like material and rock are widely encountered in geotechnical engineering,such as tunnels and mines.The existing theoretical models describing the stress-strain relationship of a combined body lack a binary feature.Based on effective medium theory,this paper presents the governing equation of the“elastic modulus”for combined and single bodies under triaxial compressive tests.A binary effective medium model is then established.Based on the compressive experiment of concretegranite combined bodies,the feasibility of determining the stress threshold based on crack axial strain is discussed,and the model is verified.The model is further extended to coal-rock combined bodies of more diverse types,and the variation laws of the compressive mechanical parameters are then discussed.The results show that the fitting accuracy of the model with the experimental curves of the concretegranite combined bodies and various types of coal-rock combined bodies are over 95%.The crack axial strain method can replace the crack volumetric strain method,which clarifies the physical meanings of the model parameters.The variation laws of matrix parameters and crack parameters are discussed in depth and are expected to be more widely used in geotechnical engineering. 展开更多
关键词 Combined body stress-strain relationship Hooke’s law effective medium theory stress threshold determination
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Cu_(3)Mo_(2)O_(9)/Mn_(0.3)Cd_(0.7)S S型异质结的构筑及其光解水产氢性能研究 被引量:2
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作者 于佳慧 姚欣彤 +4 位作者 苏萍 王仕凯 张大凤 葛博 蒲锡鹏 《聊城大学学报(自然科学版)》 2024年第1期52-61,共10页
采用超声辅助研磨煅烧法制备了Cu_(3)Mo_(2)O_(9)/Mn_(0.3)Cd_(0.7)S S型异质结光催化剂,通过X射线粉末衍射仪、扫描电子显微镜、X射线光电子能谱、固体紫外漫反射等测试技术表征了样品的物相、形貌、化学元素组成以及光吸收能力等物理... 采用超声辅助研磨煅烧法制备了Cu_(3)Mo_(2)O_(9)/Mn_(0.3)Cd_(0.7)S S型异质结光催化剂,通过X射线粉末衍射仪、扫描电子显微镜、X射线光电子能谱、固体紫外漫反射等测试技术表征了样品的物相、形貌、化学元素组成以及光吸收能力等物理化学性质。在可见光加近红外光照射下进行了光催化析氢性能测试,结果表明,Cu_(3)Mo_(2)O_(9)/Mn_(0.3)Cd_(0.7)S复合材料的光解水产氢性能均优于纯相的Mn_(0.3)Cd_(0.7)S和Cu_(3)Mo_(2)O_(9),其中Cu 3Mo 2O 9的质量分数为1%的Cu_(3)Mo_(2)O_(9)/Mn_(0.3)Cd_(0.7)S显示出最佳的产氢速率(1.554 mmol·h^(-1)·g^(-1)),是Mn 0.3 Cd_(0.7)S的5.5倍。且经过四次循环实验后仍保持较好的光催化活性。此外,根据电化学测试以及红外热成像结果提出了合理的机理,Cu 3Mo 2O 9的光热效应与S型异质结的协同作用是Cu_(3)Mo_(2)O_(9)/Mn_(0.3)Cd_(0.7)S光催化活性提高的关键。 展开更多
关键词 光解水产氢 s型异质结 Mn_(0.3)Cd_(0.7)s Cu_(3)Mo_(2)O_(9) 光热效应
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Effect of Hashimoto’s Thyroiditis on Efficacy of 131I Ablation Therapy in Intermediate- and High-Risk of Thyroid Papillary Carcinoma
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作者 Lu Zhou Gang Cheng 《Journal of Biosciences and Medicines》 2023年第4期103-113,共11页
Objective: The purpose of this study was to investigate the effect of Hashimoto’s thyroiditis on efficacy of <sup>131</sup>I ablation in intermediate- and high-risk of thyroid papillary carcinoma patients... Objective: The purpose of this study was to investigate the effect of Hashimoto’s thyroiditis on efficacy of <sup>131</sup>I ablation in intermediate- and high-risk of thyroid papillary carcinoma patients. The findings will help to develop a personalized treatment plan for patients with thyroid papillary carcinoma complicated with Hashimoto’s thyroiditis. Material and Methods: From January 2016 to December 2020, patients who were diagnosed with intermediate- and high-risk PTC with lymph node metastasis were analyzed retrospectively, excluding patients with incomplete clinical data, distant metastasis, positive TGAb, TSH Results: A total of 525 patients (166 males and 359 females) were included in the study, including 368 patients in ER group (70.1%) and 157 patients in NER group (29.9%). Eleven factors including combining Hashimoto’s thyroiditis, pre-ablative Tg levels, sex, tumor diameter, extraglandular invasion, multifocal, bilateral lesions, central lymph node metastasis, lateral lymph node metastasis, lymph node metastasis rate, thyroglobulin were statistically different between ER group and NER group with significance at P Conclusion: Hashimoto’s thyroiditis, Ps-Tg level and lateral lymph node metastasis are potential predictors for short-term efficacy of <sup>131</sup>I treatment in intermediate- and high-risk thyroid papillary carcinoma. Hashimoto’s thyroiditis, high Ps-Tg level and increased number of lateral lymph node metastasis reduce the efficacy of <sup>131</sup>I therapy in patients with intermediate and high risk thyroid papillary carcinoma. 展开更多
关键词 Papillary Thyroid Carcinoma Hashimoto’s Thyroiditis <sup>131sup>I Therapy Curative effect
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Analysis of Serum Antibody Level after COVID-19 Vaccine and Side Effects after Vaccine
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作者 Hiromi Nagashima Shinji Chiba +7 位作者 Shinnosuke Oura Itaru Fujimura Masachika Akiyama Yu Utsumi Hironori Sakai Wataru Hojo Takuya Iwabuchi Makoto Maemondo 《Advances in Infectious Diseases》 2023年第2期249-262,共14页
Background: COVID-19 has caused a large number of deaths, in the elderly. In this situation, vaccines have been considered the main strategy to combat COVID-19 and were developed worldwide in 2020. One problem with CO... Background: COVID-19 has caused a large number of deaths, in the elderly. In this situation, vaccines have been considered the main strategy to combat COVID-19 and were developed worldwide in 2020. One problem with COVID-19 vaccination is side effects after vaccination. In this report, we identify the relationship between side effects and elevation of antibodies as determined by monitoring several kinds of antibodies against COVID-19. Objective: We investigated whether the antibody level changed depending on side effects after COVID-19 vaccination. Methods: Healthy volunteers, who received two vaccinations between 10 March and 7 May 2021, were collected for this study. Information including age, gender, smoking history, medical history including allergies and side reactions after vaccination was obtained by questionnaire. Serum levels of antibodies of IgG and IgM against each S1, SP, and NP antigens of COVID-19 were evaluated frequently for 3 - 4 months after the first vaccination. Result: Ten employees working at Iwate Medical University were evaluated in this study. Side effects were observed in 7 of 10 patients, and grade 2 side effects in all 3 patients with a history of allergic disease. Serum S1 and SP IgG were elevated sufficiently in all patients. In all patients, IgG antibody titers fell below the cutoff point in approximately 3 months. No cases had elevated NP antibodies. SP IgM was elevated in three cases;all three cases with elevated IgM had allergic disease and the degree of side effects was relatively higher. Subjects with long-lasting elevated SPIgM were observed. Conclusion: S1 IgG and SP IgG exceeded the cutoff in all subjects after vaccination but decreased below the cutoff in all subjects within 4 months, regardless of side effects or allergic history. On the other hand, elevated SPIgM was suspected to be related to side effects and history of allergies, and cases with persistent elevation of SPIgM were observed. 展开更多
关键词 COVID-19 Vaccination History of Allergic Disease side effect s1 IgG sP IgG sP IgM
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基于线性密集台阵的2023年甘肃积石山M_(S)6.2地震断层低速带研究
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作者 吴柏辰 秦满忠 +3 位作者 郭晓 王亚红 孙点峰 温淑琳 《地震工程学报》 CSCD 北大核心 2024年第3期734-741,共8页
2023年12月18日,甘肃省积石山县发生M_(S)6.2逆冲型地震。该地震发生在祁连活动地块拉脊山北缘断裂带,在断裂两侧曾发生过20余次5级左右中强地震,地震活动频次高,因此研究拉脊山断裂带特征具有重要意义。根据拉脊山断裂走向和此次地震... 2023年12月18日,甘肃省积石山县发生M_(S)6.2逆冲型地震。该地震发生在祁连活动地块拉脊山北缘断裂带,在断裂两侧曾发生过20余次5级左右中强地震,地震活动频次高,因此研究拉脊山断裂带特征具有重要意义。根据拉脊山断裂走向和此次地震余震分布,在刘集乡布设一条线性密集台阵,利用不同方位的余震事件计算体波的走时延时和放大效应。结果表明,P波和S波分别存在6个采样点(约0.012 s)和15个采样点(约0.03 s)的走时延时,推断出台阵西侧存在一个约150 m宽近似垂直的断层低速带,且该结果与远震P波相似性系数矩阵结果一致。 展开更多
关键词 甘肃积石山M_(s)6.2地震 走时延时 体波放大效应 线性密集台阵 断层低速带
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Gas hydrate saturation from NGHP 02 LWD data in the Mahanadi Basin
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作者 Uma Shankar Pradeep Kumar Yadav +1 位作者 Sneha Devi Udham Singh Yadav 《Energy Geoscience》 EI 2024年第2期279-289,共11页
During the Indian National Gas Hydrate Program(NGHP)Expedition 02,Logging-while-drilling(LWD)logs were acquired at three sites(NGHP-02-11,NGHP-02-12,and NGHP-02-13)across the Mahanadi Basin in area A.We applied rock p... During the Indian National Gas Hydrate Program(NGHP)Expedition 02,Logging-while-drilling(LWD)logs were acquired at three sites(NGHP-02-11,NGHP-02-12,and NGHP-02-13)across the Mahanadi Basin in area A.We applied rock physics theory to available sonic velocity logs to know the distribution of gas hydrate at site NGHP-02-11 and NGHP-02-13.Rock physics modeling using sonic velocity at well location shows that gas hydrate is distributed mainly within the depth intervals of 150-265 m and 100 -215 mbsf at site NGHP-02-11 and NGHP-02-13,respectively,with an average saturation of about 4%of the pore space and the maximum concentration of about 40%of the pore space at 250 m depth at site NGHP-02-11,and at site NGHP-02-13 an average saturation of about 2%of the pore space and the maximum concentration of about 20%of the pore space at 246 m depth,as gas hydrate is distributed mainly within 100-246 mbsf at this site.Saturation of gas hydrate estimated from the electrical resistivity method using density derived porosity and electrical resistivity logs from Archie's empirical formula shows high saturation compared to that from the sonic log.However,estimates of hydrate saturation based on sonic P-wave velocity may differ significantly from that based on resistivity,because gas and hydrate have higher resistivity than conductive pore fluid and sonic P-wave velocity shows strong effect on gas hydrate as a small amount of gas reduces the velocity significantly while increasing velocity due to the presence of hydrate.At site NGHP-02-11,gas hydrate saturation is in the range of 15%e30%,in two zones between 150-180 and 245-265 mbsf.Site NGHP-02-012 shows a gas hydrate saturation of 20%e30%in the zone between 100 and 207 mbsf.Site NGHP-02-13 shows a gas hydrate saturation up to 30%in the zone between 215 and 246 mbsf.Combined observations from rock physics modeling and Archie’s approximation show the gas hydrate concentrations are relatively low(<4%of the pore space)at the sites of the Mahanadi Basin in the turbidite channel system. 展开更多
关键词 Mahanadi Basin Gas hydrate sonic log effective medium modeling Electrical resistivity log Archie’s analysis Gas hydrate saturation
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The Impact and Intervention of Handheld Tai Chi Water-Resistance Fitness Ball on Middle-Aged and Elderly Patients with Parkinson’s Disease
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作者 He Huang 《Health》 2024年第4期319-349,共31页
Through the use of a survey and statistical methods, this study explores the effects and interventions of handheld Tai Chi water resistance fitness balls on the elderly with Parkinson’s disease. Firstly, a questionna... Through the use of a survey and statistical methods, this study explores the effects and interventions of handheld Tai Chi water resistance fitness balls on the elderly with Parkinson’s disease. Firstly, a questionnaire on exercise compliance for patients with Parkinson’s disease was developed, and its reliability and validity were tested. Then, a survey was conducted to investigate the current status of exercise compliance among Parkinson’s disease patients, including general information, scoring status, and single and multiple factor analyses of influencing factors [1]. The results of the study show that through qualitative research, the dimensions and item pools of the questionnaire were initially constructed, and the reliability analysis of the questionnaire was conducted through Delphi expert consultation, with favorable results in terms of its reliability and validity [2]. Regarding the current status of exercise compliance among Parkinson’s disease patients, the study found that the level of exercise compliance needs improvement, and there are significant differences in exercise compliance levels among patients under different circumstances. Finally, the research results were discussed and conclusions were drawn. The innovation of this study lies in the development of a questionnaire on exercise compliance for patients with Parkinson’s disease and the preliminary qualitative research and Delphi expert consultation conducted on it, providing new ideas and methods for the study of exercise compliance. However, the study also has limitations as it did not examine the effects of other interventions on Parkinson’s disease, so further research should be conducted [3]. 展开更多
关键词 Parkinson’s Disease Exercise Compliance Tai Chi Water Resistance Fitness Ball Influencing Factors Intervention effectiveness
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基于外部气相沉积的S+C+L波段低色散斜率大有效面积非零色散位移光纤的设计与制备
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作者 查健江 王元达 +3 位作者 何学荣 侯伟 王敬胜 文建湘 《光子学报》 EI CAS CSCD 北大核心 2024年第2期52-63,共12页
针对现有光纤无法满足宽带光密集波分复用系统传输和S+C+L波段粗波分复用的要求,设计了一种具有中心凹陷的三角形芯+环形的折射率剖面,利用外部气相沉积工艺制备了一种非零色散位移光纤,并通过调整第一芯层的相对折射率和第二芯层与第... 针对现有光纤无法满足宽带光密集波分复用系统传输和S+C+L波段粗波分复用的要求,设计了一种具有中心凹陷的三角形芯+环形的折射率剖面,利用外部气相沉积工艺制备了一种非零色散位移光纤,并通过调整第一芯层的相对折射率和第二芯层与第一芯层的半径比,探究了其对光纤衰减、色散斜率和有效面积等参数的影响。研究发现,当第一芯层的相对折射率逐渐增大且第二芯层与第一芯层半径比逐渐减小时,零色散波长和有效面积逐渐减小。当第一芯层的相对折射率在0.52%~0.53%,芯层半径比在2.6~2.7时,光纤的有效面积接近70μm^(2),零色散波长在1420 nm附近,在1550 nm波段的色散系数大于8 ps·nm^(-1)·km^(-1),色散斜率为0.059 ps·nm^(-2)·km^(-1),可以较好地抑制传输过程中光非线性效应,满足长途干线网与城域网的使用要求。 展开更多
关键词 光纤通信 非零色散位移光纤 外部气相沉积工艺 s%PLUs%C%PLUs%L波段 低色散斜率 大有效面积 波分复用
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热效应作用下S波入射弹性地基自由场地地震响应研究
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作者 杨奕琪 马强 《振动与冲击》 EI CSCD 北大核心 2024年第10期114-122,共9页
基于热弹性介质中波的传播理论,建立了平面S波入射下弹性地基自由场地模型,采用亥姆霍兹矢量分解原理,对热效应作用下弹性地基自由场地中的波场进行分析,获得了热效应作用下平面S波入射弹性地基自由场地地震地面运动的解析解答。通过数... 基于热弹性介质中波的传播理论,建立了平面S波入射下弹性地基自由场地模型,采用亥姆霍兹矢量分解原理,对热效应作用下弹性地基自由场地中的波场进行分析,获得了热效应作用下平面S波入射弹性地基自由场地地震地面运动的解析解答。通过数值计算,分析了热传导系数、介质温度、热膨胀系数等热物性参数对弹性地基自由场地地震地面运动所产生的影响规律。研究结果表明:考虑热效应和不考虑热效应的两种理论模型下所得到的水平和竖向位移放大系数有着明显差异;地表水平和竖向位移放大系数以及相应的加速度随着热膨胀系数和介质温度的增大而增大;热传导系数和热通量相位延迟对地表位移放大系数和加速度的影响较小;随着入射波频率的增大,地表位移放大系数和加速度均逐渐增大。 展开更多
关键词 热弹性介质 热效应 自由场地 地震地面运动 平面s
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基于改进D-S证据理论的相控阵雷达作战效能评估
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作者 郑丽莎 尹东亮 王旋 《系统工程与电子技术》 EI CSCD 北大核心 2024年第4期1330-1336,共7页
针对相控阵雷达作战效能评估中战场环境等不确定因素的影响,采用改进Dempster-Shafer(D-S)证据理论对其进行作战效能评估方法的优化。首先,通过构建相控阵雷达作战效能评估指标体系,明确评估指标并赋值权。其次,引入Kulsinski差异和模... 针对相控阵雷达作战效能评估中战场环境等不确定因素的影响,采用改进Dempster-Shafer(D-S)证据理论对其进行作战效能评估方法的优化。首先,通过构建相控阵雷达作战效能评估指标体系,明确评估指标并赋值权。其次,引入Kulsinski差异和模糊熵方法,对传统的D-S证据理论进行改进,减少指标在融合过程中的融合权重不确定性的影响。最后,通过改进D-S证据理论对评估指标进行数据融合,建立评估准确性较高的相控阵雷达作战效能评估模型。通过算例验证分析,所提方法能够有效减少融合过程中的不确定性影响,可实现相控阵雷达作战效能评估的目的,提高作战效能评估精度。 展开更多
关键词 相控阵雷达 Dempster-shafer(D-s)证据理论 作战效能评估 Kulsinski差异 模糊熵
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多奈哌齐联合丁苯酞治疗老年阿尔茨海默病的效果及对患者Hcy、CysC、VEGF的影响
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作者 黄炜 吴珍琴 黄晓岚 《临床合理用药杂志》 2024年第24期29-33,共5页
目的观察多奈哌齐联合丁苯酞治疗老年阿尔茨海默病(AD)的效果及对患者血清同型半胱氨酸(Hcy)、胱抑素C(CysC)、血管内皮生长因子(VEGF)的影响。方法选取2021年1月—2022年6月福州市中医院收治的老年AD患者90例作为观察组,选择同期进行... 目的观察多奈哌齐联合丁苯酞治疗老年阿尔茨海默病(AD)的效果及对患者血清同型半胱氨酸(Hcy)、胱抑素C(CysC)、血管内皮生长因子(VEGF)的影响。方法选取2021年1月—2022年6月福州市中医院收治的老年AD患者90例作为观察组,选择同期进行健康体检的90例健康老年人作为健康对照组,将观察组患者按随机数字表法分为Ⅰ亚组、Ⅱ亚组、Ⅲ亚组各30例,分别给予多奈哌齐、丁苯酞及多奈哌齐+丁苯酞治疗,3组均治疗24周。治疗前、治疗24周结束时对2组受试者进行血清Hcy、CysC、VEGF检测及记录简易精神状态检查量表(MMSE)、日常生活活动能力量表(ADL)评分,根据MMSE评分将患者分为轻度、中度、重度,比较不同病情程度患者治疗前血清Hcy、CysC、VEGF水平,采用Pearson相关分析探讨Hcy、CysC、VEGF与病情程度的相关性,治疗24周结束时评价临床疗效。结果观察组血清Hcy、CysC水平明显高于健康对照组,血清VEGF水平明显低于健康对照组(P均<0.01)。轻度、中度、重度患者血清Hcy、CysC、VEGF水平比较,差异有统计学意义(F/P=20.917/<0.001、37.397/<0.001、60.507/<0.001);Pearson相关分析显示,Hcy、CysC与病情程度呈正相关(r=0.853、0.864,P<0.01),VEGF与病情程度呈负相关(r=-0.901,P<0.01)。3亚组治疗总有效率比较,差异有统计学意义(χ^(2)=6.477,P=0.039);Ⅲ亚组治疗总有效率高于Ⅰ亚组、Ⅱ亚组(χ^(2)/P=5.963/0.015、4.812/0.028),但Ⅰ亚组、Ⅱ亚组治疗总有效率比较,差异无统计学意义(P>0.05)。3亚组治疗24周后MMSE评分与血清VEGF水平较治疗前升高,ADL评分与血清Hcy、CysC水平较治疗前降低,且治疗后3亚组间MMSE、ADL评分与血清Hcy、CysC、VEGF水平比较,差异有统计学意义(P<0.01),Ⅲ亚组治疗后相应指标与Ⅰ亚组、Ⅱ亚组比较差异有统计学意义(P<0.01),但Ⅰ亚组、Ⅱ亚组比较差异无统计学意义(P>0.05)。结论Hcy、CysC、VEGF参与老年AD的形成过程,Hcy、CysC与病情程度呈正相关,VEGF与病情程度呈负相关,多奈哌齐联合丁苯酞治疗老年AD能更有效降低Hcy、CysC水平,升高VEGF水平,进而提高临床治疗效果。 展开更多
关键词 阿尔茨海默病 老年人 多奈哌齐 丁苯酞 同型半胱氨酸 胱抑素C 血管内皮生长因子 临床疗效
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Compressed H3S: Fits to the Empirical Hc2(T) Data and a Discussion of the Meissner Effect
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作者 Gulshan Prakash Malik Vijaya Shankar Varma 《World Journal of Condensed Matter Physics》 2023年第4期111-127,共17页
Based on μ-, T- and H-dependent pairing and number equations and the premise that μ(T) is predominantly the cause of the variation of the upper critical field H<sub>c</sub><sub>2</sub>(T), wh... Based on μ-, T- and H-dependent pairing and number equations and the premise that μ(T) is predominantly the cause of the variation of the upper critical field H<sub>c</sub><sub>2</sub>(T), where μ, T and H denote the chemical potential, temperature and the applied field, respectively, we provide in this paper fits to the empirical H<sub>c</sub><sub>2</sub>(T) data of H<sub>3</sub>S reported by Mozaffari, et al. (2019) and deal with the issue of whether or not H<sub>3</sub>S exhibits the Meissner effect. Employing a variant of the template given by Dogan and Cohen (2021), we examine in detail the results of Hirsch and Marsiglio (2022) who have claimed that H<sub>3</sub>S does not exhibit the Meissner effect and Minkov, et al. (2023) who have claimed that it does. We are thus led to suggest that monitoring the chemical potential (equivalently, the number density of Cooper pairs N<sub>s</sub> at T = T<sub>c</sub>) should shed new light on the issue being addressed. 展开更多
关键词 Compressed H<sub>3sub>s Upper and Lower Critical Fields Chemical Potential Generalized Pairing and Number Equations Coherence Length Penetration Depth Meissner effect
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2008年汶川M_(S)8.0地震地表破裂带沙坝村吴家院一带几何结构变化特征研究
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作者 沈长伟 王虎 +2 位作者 邓林 李开锦 薛浩 《四川地震》 2024年第2期9-14,43,共7页
以往学者通常侧重于大尺度(数公里级别)的地表形态对大地震同震地表破裂的影响研究,而鲜有涉及短距离尺度(10~100 m级)的相关报道。本文基于2008年汶川M_(S)8.0地震地表破裂带沙坝村吴家院一带的几何展布样式与微地貌测绘,为回答短距离... 以往学者通常侧重于大尺度(数公里级别)的地表形态对大地震同震地表破裂的影响研究,而鲜有涉及短距离尺度(10~100 m级)的相关报道。本文基于2008年汶川M_(S)8.0地震地表破裂带沙坝村吴家院一带的几何展布样式与微地貌测绘,为回答短距离尺度是否存在显著的几何结构变化和探究其影响因素提供一个典型案例。具体通过无人机摄影测量技术及激光雷达技术精确的获取了该段落断层展布特征及近断层地形地貌数据,发现吴家院一带地表破裂带在西南侧地形相对稳定无起伏时,破裂带集中为一支断层,而往北东向延伸遇到地形起伏如负地形时,断层分叉为三支分支断层。上述研究结果表明局部范围内地形起伏可能会导致同震地表破裂发生分叉现象,单一断层可能弥散为多支断层。 展开更多
关键词 地表破裂带 地形效应 激光雷达 无人机摄影测量 汶川M_(s)8.0地震
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四川地区场地放大系数特征分析及在强地震动模拟中的应用——以2022年芦山M_(S)6.1地震为例 被引量:1
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作者 傅磊 谢俊举 +3 位作者 陈苏 张斌 张旭 李小军 《地球物理学报》 SCIE EI CAS CSCD 北大核心 2023年第7期2933-2950,共18页
基于四川地区62个强震动台站的场地资料,依据中国抗震规范及美国下一代衰减的Geomatrix(GMX)场地分类方法将台站场地进行了划分,并以台站的场地放大系数和高频衰减参数(κ0)为基础数据,研究了不同场地类型的场地放大系数平均特征.结果显... 基于四川地区62个强震动台站的场地资料,依据中国抗震规范及美国下一代衰减的Geomatrix(GMX)场地分类方法将台站场地进行了划分,并以台站的场地放大系数和高频衰减参数(κ0)为基础数据,研究了不同场地类型的场地放大系数平均特征.结果显示,在中国Ⅱ类场地中,受狭窄山间谷底地形效应影响,满足GMX的C类场地在大于10 Hz的高频段有明显放大;受深厚软弱沉积层影响,满足GMX的D类场地在小于5 Hz的低频段放大效应显著.考虑震源滑动模型、山区和盆地品质因子差异、局部场地效应,采用区域内余震平均应力降,通过随机有限断层法模拟了2022年芦山M_(S)6.1地震中9个断层距(Rrup)<100 km的强震动台站的加速度时程、傅里叶振幅谱(FAS)和反应谱(PSA).结果显示,模拟结果与观测加速度时程的S波部分符合良好.在8 s以下周期范围内模拟与观测FAS和PSA形状和幅值基本一致.较好地模拟结果支持此次地震为2013年芦山M_(S)7.0芦山地震的一次余震.另外,模拟结果体现了此次地震在Rrup<35 km范围内有明显的方向性效应,与观测数据相符.最后,考虑各类场地的场地放大系数和κ0的平均特性,比较了此次地震中Rrup<150 km的167个盆地和130个山区烈度台观测和模拟峰值加速度(PGA)和峰值速度(PGV),以及周期为0.5 s、1.0 s、5.0 s和8.0 s的PSA幅值随断层距的衰减特性.结果显示,山区和盆地的地震动参数随距离的衰减特性较为相似,山区和盆地的PGA、PGV强度相当.但是,在周期大于1.0 s的长周期段,盆地的反应谱幅值整体上大于山区. 展开更多
关键词 芦山M_(s)6.1地震 场地效应 强地震动 随机有限断层法 方向性效应
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Pretreatment with Rhodiola Rosea Extract Reduces Cognitive Impairment Induced by Intracerebroventricular Streptozotocin in Rats: Implication of Anti-oxidative and Neuroprotective Effects 被引量:14
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作者 PETER CHUNG 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2009年第4期318-326,共9页
Objective To investigate the pretreatment effects of Rhodiola rosea (R. rosea) extract on cognitive dysfunction, oxidative stress in hippocampus and hippocampal neuron injury in a rat model of Alzheimer's disease ... Objective To investigate the pretreatment effects of Rhodiola rosea (R. rosea) extract on cognitive dysfunction, oxidative stress in hippocampus and hippocampal neuron injury in a rat model of Alzheimer's disease (AD). Methods Male Sprague-Dawley rats were pretreated with R. rosea extract at doses of 1.5, 3.0, and 6.0 g/kg for 3 weeks, followed by bilateral intracerebroventricular injection with streptozotocin (1.5 mg/kg) on days 1 and 3. Behavioral alterations were monitored after 2 weeks from the lesion using Morris water maze task. Three weeks after the lesion, the rats were sacrificed for measuring the malondialdehyde (MDA), glutathione reductase (GR) and reduced glutathione (GSH) levels in hippocampus and histopathology of hippocampal neurons. Results The MDA level was significantly increased while the GR and GSH levels were significantly decreased with striking impairments in spatial learning and memory and severe damage to hippocampal neurons in the model rat induced by intracerebroventricular injection of streptozotocin. These abnormalities were significantly improved by pretreatment with R. rosea extract (3.0 g/kg). Conclusion R. rosea extract can protect rats against cognitive deficits, neuronal injury and oxidative stress induced by intracerebroventricular injection of streptozotocin, and may be used as a potential agent in treatment of neurodegenerative diseases such as AD. 展开更多
关键词 Rhodiola rosea Oxidative stress Neuroprotective effect Learning and memory Alzheimer's disease Intracerebroventricular streptozotocin
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Effect of Friedel's salt on strength enhancement of stabilized chloride saline soil 被引量:6
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作者 程寅 李战国 +1 位作者 黄新 白晓红 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第4期937-946,共10页
In the field of soil stabilization, only calcium silicate hydrate(CSH) and ettringite(AFt) as hydration products have been reported to directly contribute to the strength enhancement of the soil. A chloride dredger fi... In the field of soil stabilization, only calcium silicate hydrate(CSH) and ettringite(AFt) as hydration products have been reported to directly contribute to the strength enhancement of the soil. A chloride dredger fill, an artificial chloride saline soil, and a non-saline soil were stabilized by Portland cement(PC) and PC with Ca(OH)_2(CH) with different contents. A series of unconfined compressive strength(UCS) tests of stabilized soil specimen after curing for 7 d and 28 d were carried out, and the hydration products and microstructure of the specimens were observed by X-ray diffractometry(XRD), scanning electronic microscopy(SEM), and energy-dispersive X-ray analysis(EDXA). The results showed that the strengths of PC+CH-stabilized chloride saline soils were much higher than those of PC-stabilized soils. A new hydration product of calcium aluminate chloride hydrate, also known as Friedel's salt, appeared in the PC+CH-stabilized chloride saline soils. The solid-phase volume of Friedel's salt expanded during the formation of the hydrate; this volume filled the pores in the stabilized soil. This pore-filling effect was the most important contribution to the significantly enhanced strength of the PC+CH-stabilized chloride saline soils. On the basis of this understanding, a new optimized stabilizer was designed according to the concept that the chloride in saline soil could be utilized as a component of the stabilizer. The strength of the chloride saline soils stabilized by the optimized stabilizer was even further increased compared with that of the PC+CH-stabilized soils. 展开更多
关键词 CHLORIDE sALINE sOIL sTABILIZED sOIL Friedel’s sALT strength enhancement effect
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Surface-effects-dominated thermal and mechanical responses of zinc oxide nanobelts 被引量:6
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作者 A. J. Kulkarni. M. Zhou 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2006年第3期217-224,共8页
t Molecular dynamics (MD) simulations are carried out to characterize the mechanical and thermal responses of [011^-1]-oriented ZnO nanobelts with lateral dimensions of 21.22A × 18.95 A, 31.02A× 29.42 A, a... t Molecular dynamics (MD) simulations are carried out to characterize the mechanical and thermal responses of [011^-1]-oriented ZnO nanobelts with lateral dimensions of 21.22A × 18.95 A, 31.02A× 29.42 A, and40.81A ×39.89A over the temperature range of 300-1000 K. The Young's modulus and thermal conductivity of the nanobelts are evaluated. Significant surface effects on properties due to the highsurface-to-volume ratios of the nanobelts are observed. For the mechanical response, surface-stress-induced internal stress plays an important role. For the thermal response, surface scattering of phonons dominates. Calculations show that the Young's modulus is higher than the corresponding value for bulk ZnO and decreases by -33% as the lateral dimensions increase from 21.22 A × 18.95A to 40.81 A × 39.89A. The thermal conductivity is one order of magnitude lower than the corresponding value for bulk ZnO single crystal and decreases with wire size. Specifically, the conductivity of the 21.22 A × 18.95 A belt is approximately (31-18)% lower than that of the 40.81 A × 39.89 A belt over the temperature range analyzed. A significant dependence of properties on temperature is also observed, with the Young's modulus decreasing on average by 12% and the conductivity decreasing by 50% as temperature increases from 300 K to 1000 K. 展开更多
关键词 Zinc oxide nanobelts surface effects size dependence Young's modulus Thermal conductivity
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