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Lactoferrin modification of berberine nanoliposomes enhances the neuroprotective effects in a mouse model of Alzheimer’s disease 被引量:6
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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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Verification of the Physiological Therapeutic Effects of Harvesting Activities in a Patient with Moderate Alzheimer’s Disease with Long-Term Agricultural Experience
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作者 Kikuo Eguchi Seigo Koura +1 位作者 Nao Eguchi Akihiko Kondou 《Open Journal of Therapy and Rehabilitation》 2024年第3期236-244,共9页
Background: Harvesting activities have proven effective in reducing stress in patients with dementia. At a psychiatric hospital, occupational therapists (OT) made patients with dementia perform vegetable harvesting ac... Background: Harvesting activities have proven effective in reducing stress in patients with dementia. At a psychiatric hospital, occupational therapists (OT) made patients with dementia perform vegetable harvesting activities as a part of their treatment. The patients became calmer and began to smile not only after but also before and during harvesting activity. Therefore, this study aimed to measure autonomic nervous system (ANS) responses over time in a female patient in her 80s with moderate Alzheimer’s disease (AD) who had experience in farming when performing harvesting activities. Additionally, this study aimed to consider factors associated with changes in ANS responses over time and to verify the physiological therapeutic effects of harvesting activities. Methods: An OT with more than 10 years of experience and a good relationship with the patient conducted one-on-one sessions with the patient. Harvesting activity was performed in a courtyard with trees. The patient harvested lettuce (three lettuce plants) grown in a planter while sitting on a chair. Additionally, the planter was set up on a desk. ANS responses were measured over time from before to after the activity for different events at six time periods. Changes in the patient’s ANS responses were assessed during each period. Results: With the involvement of environmental factors and OT during harvesting activities, parasympathetic nervous system (PNS) activity significantly increased. This may lead to improved mental stability. Conclusion: The findings of this study indicate that implementing harvesting activities may have a positive effect on the PNS in patients with AD with long-term agricultural experience. However, further studies with a larger sample size and multidimensional evaluations are needed. 展开更多
关键词 Alzheimer’s Disease Autonomic Nervous Response Harvesting Activity Therapeutic effects
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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:5
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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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A novel binary effective medium model to describe the prepeak stressstrain relationship of combined bodies of rock-like material and rock 被引量:2
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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:3
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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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简易烈度计记录的噪声水平评价:以泸定M_(S)6.8级地震为例
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作者 郭文轩 任叶飞 +4 位作者 姚鑫鑫 岸田忠大 江鹏 王宏伟 温瑞智 《振动与冲击》 EI CSCD 北大核心 2024年第18期313-320,共8页
在我国地震预警和烈度速报系统中,烈度计被广泛使用。烈度计的频谱特征主要是通过检定实验室进行标定,但在破坏性地震中,烈度计响应特点缺少必要的研究分析。该文以2022年四川泸定M_(S)6.8级地震为例,对比分析了烈度计记录和强震仪记录... 在我国地震预警和烈度速报系统中,烈度计被广泛使用。烈度计的频谱特征主要是通过检定实验室进行标定,但在破坏性地震中,烈度计响应特点缺少必要的研究分析。该文以2022年四川泸定M_(S)6.8级地震为例,对比分析了烈度计记录和强震仪记录在噪声水平、信噪比(signal-to-noise ratio,SNR)、高通滤波截止频率(f_(HP))取值以及有效周期范围(T_(max))方面的特点,综合评价了烈度计记录的频谱特征,分析了噪声影响。得到以下结论:在整个频域范围内,烈度计记录的SNR要比强震仪记录平均意义上低一个数量级,可以估计烈度计动态范围较强震仪大致低20 dB;烈度计记录的最佳f_(HP)取值相较于强震仪记录存在更大的不确定性,尤其是在竖直方向上;烈度计记录的最佳f_(HP)取值更大,反应谱T_(max)较传统强震仪记录在水平方向小1~2 s,在竖直方向小3 s左右。该研究结果有助于合理应用烈度计记录,服务地震学和地震工程学相关研究。 展开更多
关键词 烈度计记录 信噪比(sNR) 高通滤波截止频率 有效周期范围 泸定6.8级地震
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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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Dynamic Uncertainty:Exploring the Spatial Order of Future Digital Architecture
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作者 Yuxin Zhao 《Journal of Civil Engineering and Architecture》 2024年第10期475-484,共10页
The spatial order of architecture has been significantly impacted by digital architectural design and production,creating a dynamic uncertainty.This study aims to explore digital architecture from the perspective of s... The spatial order of architecture has been significantly impacted by digital architectural design and production,creating a dynamic uncertainty.This study aims to explore digital architecture from the perspective of spatial order,discussing the antidote/poison effect caused by digital technologies in architectural practice and the cultural digital changes in digital architectures.The study selected four digital architecture cases,including the(W)rapper at Los Angeles by Eric Owen Moss,Beijing Daxing International Airport by Zaha Hadid,3D Print Niaokan Bridge by Xu Weiguo,and World Internet Conference Center by Yuan Feng.This study is hypothesising that the future special order of digital architectures will be a dynamic and balanced new spatial order.This new order includes the symbiosis of a human-machine and virtual-real hierarchy;the interactive co-existence between nature,humanity and technology;and the creative multi-immersive sharing of parametric information,built-environment resources and cultural artistic information.The evolution of spatial order of future digital architecture will be discussed in connection with the idea of the metaverse.The value of this work is its ability to inspire a broader examination of the new order of digital architectural space. 展开更多
关键词 spatial superimposition digital technology’s antidote&poison effect the spatial order of digital architectures alteration of spatial order
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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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朱氏滋脾固肾方Ⅰ号对慢性肾脏病2~4期脾肾气虚证症状评分、SCr及BUN的影响
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作者 费佳 马源 朱辟疆 《西部中医药》 2024年第8期111-114,共4页
目的:探讨朱氏滋脾固肾方Ⅰ号治疗慢性肾脏病(chronic kidney disease,CKD)2~4期脾肾气虚证的临床效果及对症状评分、血清肌酐(Serum creatinine,SCr)、血清尿素氮(blood urea nitrogen,BUN)等指标的影响。方法:选取CKD 2~4期患者60例,... 目的:探讨朱氏滋脾固肾方Ⅰ号治疗慢性肾脏病(chronic kidney disease,CKD)2~4期脾肾气虚证的临床效果及对症状评分、血清肌酐(Serum creatinine,SCr)、血清尿素氮(blood urea nitrogen,BUN)等指标的影响。方法:选取CKD 2~4期患者60例,依据随机数字表法分为观察组和对照组各30例。对照组采取西医常规治疗,观察组在对照组治疗基础上联合朱氏滋脾固肾方Ⅰ号治疗,两组患者均持续治疗12周,后续治疗在专科门诊随访。比较两组临床效果、症状评分、生活质量评分、肾功能指标水平(SCr、BUN)及不良反应情况。结果:观察组总有效率为86.67%(26/30),高于对照组的60.00%(18/30)(P<0.05)。治疗后两组各项症状评分、SCr及BUN水平均较治疗前下降(P<0.05),生活质量评分均上升(P<0.05),且观察组上述指标下降或上升较对照组显著(P<0.05)。两组不良反应发生率比较差异无统计学意义(P>0.05)。结论:朱氏滋脾固肾方Ⅰ号治疗CKD 2~4期脾肾气虚证患者具有显著疗效,可以改善患者肾功能及生活质量。 展开更多
关键词 肾脏病 慢性 朱氏滋脾固肾方Ⅰ号 肾功能 生活质量 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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创业投资声誉、创业板IPOs初始收益和长期业绩 被引量:11
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作者 文守逊 张泰松 黄文明 《审计与经济研究》 CSSCI 北大核心 2012年第4期104-112,共9页
以我国创业板市场IPOs为样本,引入创业投资声誉对IPO折抑价理论模型进行修正,采用多元回归和两阶段回归方法,实证检验创业投资声誉与创业板IPOs初始收益和长期业绩之间的关系后发现:我国创业板市场中创业投资核证监督作用微弱;创业投资... 以我国创业板市场IPOs为样本,引入创业投资声誉对IPO折抑价理论模型进行修正,采用多元回归和两阶段回归方法,实证检验创业投资声誉与创业板IPOs初始收益和长期业绩之间的关系后发现:我国创业板市场中创业投资核证监督作用微弱;创业投资声誉对IPOs初始收益无显著影响;创业投资声誉对IPO后企业长期业绩有显著正效应。本文的研究结论对创投声誉下的创业板发行制度建设有积极作用。 展开更多
关键词 创业投资声誉 创业板 ipo折抑价 初始收益 长期业绩 ipos效应
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