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Photonics Research 2022年第2期10卷 289-296页

作者： Dayong Wang Duoxuan Ma Kunlun Li Yaya Zhang Jie Zhao Yunxin Wang Lu rong College of Physics and Optoelectronics Faculty of ScienceBeijing University of TechnologyBeijing 100124China Beijing Engineering Research Center of Precision Measurement Technology and Instruments Beijing 100124China

Massive usage scenarios prompt the prosperity of terahertz refractive index(THz RI) measurement ***, they are very difficult in measuring the full-field dynamical RI distributions of either solid samples without a priori thickness or liquid samples. In this study, we propose total internal reflection THz digital holography and apply it for measuring RI distributions for both solid and liquid samples dynamically. An RI measurement model is established based on an attenuated total reflection prism with a pitching angle. The pitching angle and the field of view can be numerically calculated from the spectrogram of the off-axis Fresnel hologram,which solves the adjustment of the visually opaque prism irradiated by the invisible THz beam. Full-field RI distributions of the droplets of solid-state soy wax and distilled water are obtained and compared with THz time-domain spectroscopy. The evaporation of an ethanol solution droplet is recorded, and the variation of the RI distribution at the sample–prism interface is quantitatively visualized with a temporal resolution of 10 Hz. The proposed method greatly expands the sample range for THz RI measurements and provides unprecedented insight into investigating spontaneous and dynamic THz phenomena.

关键词： refractive distribution field

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车辆检测设备散热设计与仿真分析

机械研究与应用 2024年第3期37卷 147-149,155页

作者：范永佟世继施桢蓉连云港杰瑞电子有限公司江苏连云港222006

为了保证高功耗车辆检测设备在高温环境下的工作性能,使用热仿真软件,研究均温板、翅片和界面导热材料等散热结构对车辆检测设备散热性能的影响,并基于仿真结果对设备的散热结构进行优化;制作样机后,在高温箱里进行样机试验,并将试验结... 详细信息

为了保证高功耗车辆检测设备在高温环境下的工作性能,使用热仿真软件,研究均温板、翅片和界面导热材料等散热结构对车辆检测设备散热性能的影响,并基于仿真结果对设备的散热结构进行优化;制作样机后,在高温箱里进行样机试验,并将试验结果与仿真结果进行对比。结果显示:均温板具有超高的导热系数,可以降低扩散热阻,有利于降低芯片温度;增高机箱翅片的高度可使降温效果极为明显;调整翅片间距和厚度、增加基座的厚度以及选取厚度合适、导热系数高的硅胶垫片等措施均能一定程度上提高设备的散热能力。这些散热措施有效保证了设备的稳定运行,为类似产品的设计提供了指导。

关键词：高功耗高温环境均温板翅片硅胶垫片

Seismic performance of fabricated continuous girder bridge with grouting sleeve-prestressed tendon composite connections

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结构与土木工程前沿:英文版 2023年第6期17卷 827-854页

作者： Jin WANG Weibing XU Xiuli DU Yanjiang CHEN Mengjia DING rong FANG Guang YANG School of Water Resources and Hydropower Engineering North China Electric Power UniversityBeijing102206China Beijing Key Laboratory of Earthquake Engineering and Structural Retrofit Beijing University of TechnologyBeijing100124China Key Laboratory of Urban Security and Disaster Engineering of China Ministry of Education Beijing University of TechnologyBeijing100124China

The seismic performance of a fully fabricated bridge is a key factor limiting its *** this study,a fiber element model of a fabricated concrete pier with grouting sleeve-prestressed tendon composite connections was built and verified.A numerical analysis of three types of continuous girder bridges was conducted with different piers:a cast-in-place reinforced concrete pier,a grouting sleeve-fabricated pier,and a grouting sleeve-prestressed tendon composite fabricated ***,the seismic performance of the composite fabricated pier was *** results show that the OpenSees fiber element model can successfully simulate the hysteresis behavior and failure mode of the grouted sleeve-fabricated *** traditional non-near-fault ground motions,the pier top displacements of the grouting sleeve-fabricated pier and the composite fabricated pier were less than those of the cast-in-place reinforced concrete *** composite fabricated pier had a good self-centering *** addition,the plastic hinge zones of the grouting sleeve-fabricated pier and the composite fabricated pier shifted to the joint seam and upper edge of the grouting sleeve,*** composite fabricated pier with optimal design parameters has good seismic performance and can be applied in high-intensity seismic areas;however,the influence of pile-soil interaction on its seismic performance should not be ignored.

关键词： seismic performance continuous girder bridge grouting sleeve-prestressed tendon composite connections grouted sleeve connection design parameters

Symmetrical Independence Tests for Two Random Vectors with Arbitrary Dimensional Graphs

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Acta Mathematica Sinica,English Series 2022年第4期38卷 662-682页

作者： Jia Min LIU Gao rong LI Jian Qiang ZHANG Wang Li XU Center for Applied Statistics Renmin University of ChinaBeijing 100872P.R.China School of Statistics Beijing Normal UniversityBeijing 100875P.R.China

Test of independence between random vectors X and Y is an essential task in statistical *** type of testing methods is based on the minimal spanning tree of variables X and *** main idea is to generate the minimal spanning tree for one random vector X,and for each edges in minimal spanning tree,the corresponding rank number can be calculated based on another random vector *** resulting test statistics are constructed by these rank ***,the existed statistics are not symmetrical tests about the random vectors X and Y such that the power performance from minimal spanning tree of X is not the same as that from minimal spanning tree of *** addition,the conclusion from minimal spanning tree of X might conflict with that from minimal spanning tree of *** order to solve these problems,we propose several symmetrical independence tests for X and *** exact distributions of test statistics are investigated when the sample size is ***,we study the asymptotic properties of the statistics.A permutation method is introduced for getting critical values of the *** with the existing methods,our proposed methods are more efficient demonstrated by numerical analysis.

关键词： Exact distribution minimal spanning tree asymptotic distribution symmetrical independence test

宫颈癌患者lncRNA HAND2-AS1表达及其对宫颈癌Caski细胞增殖、侵袭和迁移能力的影响

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检验医学 2024年第5期39卷 429-437页

作者：张晓科褚艳荣王荣崔发财焦作市妇幼保健院检验科河南焦作454000 焦作市妇幼保健院妇产科河南焦作454000 河南省人民医院郑州大学人民医院检验科河南郑州450003

目的探讨宫颈癌患者血清长链非编码RNA(lncRNA)心脏和神经嵴衍生物表达转录本2反义序列1(HAND2-AS1)表达的临床意义,分析lncRNA HAND2-AS1对宫颈癌Caski细胞增殖、侵袭和迁移的影响机制。方法采用基因表达交互分析(GEPIA)数据库分析lncR... 详细信息

目的探讨宫颈癌患者血清长链非编码RNA(lncRNA)心脏和神经嵴衍生物表达转录本2反义序列1(HAND2-AS1)表达的临床意义,分析lncRNA HAND2-AS1对宫颈癌Caski细胞增殖、侵袭和迁移的影响机制。方法采用基因表达交互分析(GEPIA)数据库分析lncRNA HAND2-AS1在宫颈癌组织和正常宫颈组织中的表达情况。选取2019年1月—2021年12月焦作市妇幼保健院宫颈癌患者48例(宫颈癌组)、宫颈上皮内瘤变(CIN)患者48例(CIN组)和健康体检者48名(正常对照组)。收集其中14例宫颈癌患者术后癌组织和癌旁组织(距癌组织边缘>2 cm)样本,同时收集所有研究对象血清样本和临床资料,检测lncRNA HAND2-AS1相对表达量。将宫颈癌细胞系Caski按转染质粒的不同分为过表达组(转染pcDNA3.1-HAND2-AS1)和阴性对照组(转染pcDNA3.1-NC)、干扰组(转染si-HAND2-AS1)和干扰对照组(转染si-NC)。采用CCK-8实验、Transwell实验和划痕实验检测细胞的增殖、侵袭和迁移能力,采用免疫印迹法检测细胞内磷脂酰肌醇3-激酶(PI3K)、磷酸化磷脂酰肌醇3-激酶(p-PI3K)、蛋白激酶B(Akt)和磷酸化蛋白激酶B(p-Akt)的表达情况。结果GEPIA数据库分析结果显示,宫颈癌组织lncRNA HAND2-AS1表达显著低于正常宫颈上皮组织(P0.05)。不同肿瘤大小、国际妇产科学联合会(FIGO)分期和有无淋巴转移的宫颈癌患者之间血清lncRNA HAND2-AS1相对表达量差异均有统计学意义(P0.05)。结论宫颈癌患者血清lncRNA HAND2-AS1呈低表达,且与病情严重程度有关。lncRNA HAND2-AS1可能通过调控PI3K/Akt信号通路影响宫颈癌细胞的增殖、侵袭和迁移。

关键词：心脏和神经嵴衍生物表达转录本2反义序列1 长链非编码RNA 宫颈癌侵袭迁移

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赤霞珠葡萄酒颜色相关物质分析及可视化表征

食品与发酵工业 2024年第12期50卷 127-134,I0007页

作者：高琛瑜董荣石淼李飞飞乔丹李记明庞红勋周元张珍珍新疆农业大学食品科学与药学学院新疆乌鲁木齐830000 新疆张裕巴保男爵酒庄有限公司新疆石河子832061

选取新疆天山北麓产区赤霞珠干红葡萄酒从酒精发酵结束至最终色泽衰退(深紫红色-黄褐色)过程中10款样品为试材,测定葡萄酒的基础理化指标、CIELab参数、多酚类物质含量、总色素、聚合色素等指标,针对其进行皮尔逊相关性分析,基于存在相... 详细信息

选取新疆天山北麓产区赤霞珠干红葡萄酒从酒精发酵结束至最终色泽衰退(深紫红色-黄褐色)过程中10款样品为试材,测定葡萄酒的基础理化指标、CIELab参数、多酚类物质含量、总色素、聚合色素等指标,针对其进行皮尔逊相关性分析,基于存在相关性的基础上利用偏最小二乘法-判别分析筛选样品的特征指标,最终利用可视化表征直观反映酒体颜色及特征指标相对含量。结果表明,基础理化指标、多酚类物质含量等指标与CIELab参数之间均呈现相关性。偏最小二乘法-判别分析和CIELab颜色空间表征及二维灰度图表明,酒体呈现紫红色时,酒体的主要特征指标为L^(*)(57.97~81.21)、总单宁含量(4322.66~4385.43 mg/L)。酒体呈现胭脂红色时,酒体的主要特征指标为a^(*)(14.69~16.41)、总酚含量(2157.59~2983.46 mg/L)、总单宁含量(3302.57~3459.51 mg/L)。酒体呈现宝石红色时,酒体的主要特征指标为a^(*)(18.13~20.52)、苹果酸含量(1.10~1.40 g/L)、单宁含量(4558.06~4652.22 mg/L)。酒体呈现砖红色时,酒体的主要特征指标为总单宁含量(4762.08~5185.81 mg/L)、总酚含量(3568.87~3809.33 mg/L)。当总酚含量低于2000 mg/L时,酒体黄化程度严重且不再适宜陈酿。该方法直观反映了不同色泽赤霞珠葡萄酒颜色及其特征指标信息,能够良好鉴别区分不同色泽赤霞珠葡萄酒,为构建新疆天山北麓产区不同色泽赤霞珠葡萄酒评价体系奠定基础。

关键词：葡萄酒颜色可视化表征 CIELab参数多酚类物质颜色品质评价

Five new spirosterol saponins from Allii Macrostemonis Bulbus

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Chinese Journal of Natural Medicines 2023年第3期21卷 226-232页

作者： WANG rong WANG Lulu ZHANG Manli GUO Yadi ZHANG Jing MA Guoxu College of Chinese Medicinal Materials Jilin Agricultural UniversityChangchun 130118China College of Medicine Changchun University of Science and TechnologyChangchun 130600China Key Laboratory of Bioactive Substances and Resource Utilization of Chinese Herbal Medicine Institute of Medicinal Plant DevelopmentPeking Union Medical College and Chinese Academy of Medical SciencesBeijing 100193China

Five new spirostanol saponins(1−5)and seven known compounds(6−12)were isolated from the n-butanol fraction of 75%ethanol extract of Allii Macrostemonis *** identification and structural elucidation of all the isolates were performed through extensive 1D and 2D NMR experiments,HR-ESI-MS data analysis and comparisons with literature *** evaluation showed that compounds 6−11 exhibited certain scavenging effects on ABTS radical,where compounds 6,7 and 11 had IC50 values of 0.208,0.057 and 0.014 mg·mL−1,respectively.

关键词： Allii Macrostemonis Bulbus Spirosterol saponin Antioxidant

重症脑卒中患者益生菌联合早期肠内营养治疗前后营养指标、炎症因子水平变化及预后危险因素分析

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临床和实验医学杂志 2024年第3期23卷 241-245页

作者：刘洁张新杰杨秀荣邢台市第三医院重症医学科河北邢台054000 邢台市第三医院康复科河北邢台054000

目的分析重症脑卒中患者益生菌联合早期肠内营养治疗前后营养指标、炎症因子水平变化及预后危险因素。方法回顾性选取自2020年1月至2022年10月邢台市第三医院收治的104例重症脑卒中患者作为研究对象,按照治疗方法不同将其分为对照组和... 详细信息

目的分析重症脑卒中患者益生菌联合早期肠内营养治疗前后营养指标、炎症因子水平变化及预后危险因素。方法回顾性选取自2020年1月至2022年10月邢台市第三医院收治的104例重症脑卒中患者作为研究对象,按照治疗方法不同将其分为对照组和观察组,各52例。两组均在常规治疗的基础上,对照组予以早期肠内营养治疗,观察组予以益生菌联合早期肠内营养治疗,持续治疗14 d。比较两组治疗后1 d的营养指标(总蛋白、前清蛋白、血红蛋白、甘油三酯)、炎症因子[超敏C-反应蛋白(hs-CRP)、降钙素原、白细胞计数(WBC)]、美国国立卫生研究院卒中量表(NIHSS)评分、急性生理学及慢性健康状况评分系统Ⅱ(APACHEⅡ)评分、格拉斯哥昏迷指数(GCS)评分,以改良Rankin量表评分评价预后,使用单因素分析及多因素Logistic回归分析重症脑卒中患者预后的危险因素。结果观察组治疗后1 d的总蛋白、前清蛋白、血红蛋白、甘油三酯水平分别为(67.83±5.60)g/L、(224.15±26.75)mg/L、(144.13±8.77)g/L、(1.64±0.52)mmol/L,均高于对照组[(61.37±4.56)g/L、(172.56±18.73)mg/L、(130.68±6.74)g/L、(1.42±0.36)mmol/L],差异均有统计学意义(P<0.05)。观察组治疗后1 d的hs-CRP、降钙素原、WBC水平分别为(17.04±4.14)mg/L、(3.06±0.57)ng/L、(10.08±2.12)×10^(9)/L,均低于对照组[(26.14±5.62)mg/L、(5.17±1.28)ng/L、(13.30±2.87)×10^(9)/L],差异均有统计学意义(P<0.05)。观察组治疗后1 d NIHSS评分、APACHEⅡ评分分别为(7.68±1.43)、(9.76±2.31)分,均低于对照组[(10.45±1.72)、(13.16±2.85)分],GCS评分为(13.48±0.52)分,高于对照组[(12.26±0.48)分],差异均有统计学意义(P<0.05)。经单因素分析及多因素Logistic回归分析,高龄、NIHSS评分高、营养不良及APACHEⅡ评分高均是重症脑卒中患者预后的危险因素(P<0.05)。结论益生菌联合早期肠内营养治疗能够有效改善重症脑卒中患者的营养状态,降低炎症反应水平,提高疗效,而患者的预后与年龄、病情轻重和营养状态有关,值得临床予以重视。

关键词：重症脑卒中益生菌早期肠内营养营养指标炎症因子预后

Factors Influencing Alzheimer's Disease Risk: Whether and How They are Related to the APOE Genotype

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Neuroscience Bulletin 2022年第7期38卷 809-819页

作者： rong Zhang Xiaojiao Xu Hang Yu Xiaolan Xu Manli Wang Weidong Le Institute of Neurology Sichuan Academy of Medical SciencesSichuan Provincial People's HospitalUniversity of Electronic Science and Technology of ChinaChengdu 611731China

Alzheimer's disease(AD)is the most prevalent neurodegenerative disease featuring progressive cognitive *** the etiology of late-onset AD remains unclear,the close association of AD with apolipoprotein E(APOE),a gene that mainly regulates lipid metabolism,has been firmly established and may shed light on the exploration of AD pathogenesis and ***,various confounding factors interfere with the APOE-related AD risk,raising questions about our comprehension of the clinical findings concerning *** this review,we summarize the most debated factors interactingwith theAPOEgenotype and ADpathogenesis,depict the extent to which these factors relate to APOEdependent AD risk,and discuss the possible underlying mechanisms.

关键词： Apolipoprotein E Alzheimer's disease Ethnicity Diet Geographic factor Aging Gender

Ontology-Based BERT Model for Automated Information Extraction from Geological Hazard Reports

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地球科学学刊:英文版 2023年第5期34卷 1390-1405页

作者： Kai Ma Miao Tian Yongjian Tan Qinjun Qiu Zhong Xie rong Huang Hubei Key Laboratory of Intelligent Vision Based Monitoring for Hydroelectric Engineering China Three Gorges UniversityYichang 443002China College of Computer and Information Technology China Three Gorges UniversityYichang 443002China Hubei Engineering Technology Research Center for Farmland Environment Monitoring China Three Gorges UniversityYichang 443002China School of Computer Science China University of GeosciencesWuhan 430074China Key Laboratory of Urban Land Resources Monitoring and Simulation Ministry of Natural ResourcesShenzhen 518034China Beijing Key Laboratory of Urban Spatial Information Engineering Beijing 100045China College of Economics and Management China Three Gorges UniversityYichang 443002China

Geological knowledge can provide support for knowledge discovery, knowledge inference and mineralization predictions of geological big data. Entity identification and relationship extraction from geological data description text are the key links for constructing knowledge graphs. Given the lack of publicly annotated datasets in the geology domain, this paper illustrates the construction process of geological entity datasets, defines the types of entities and interconceptual relationships by using the geological entity concept system, and completes the construction of the geological corpus. To address the shortcomings of existing language models(such as Word2vec and Glove) that cannot solve polysemous words and have a poor ability to fuse contexts, we propose a geological named entity recognition and relationship extraction model jointly with Bidirectional Encoder Representation from Transformers(BERT) pretrained language model. To effectively represent the text features, we construct a BERT-bidirectional gated recurrent unit network(BiGRU)-conditional random field(CRF)-based architecture to extract the named entities and the BERT-BiGRU-Attention-based architecture to extract the entity relations. The results show that the F1-score of the BERT-BiGRU-CRF named entity recognition model is 0.91 and the F1-score of the BERT-BiGRU-Attention relationship extraction model is 0.84, which are significant performance improvements when compared to classic language models(e.g., word2vec and Embedding from Language Models(ELMo)).

关键词： ontology BERT model name entity recognition relation extraction knowledge graph