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放射性脑损伤的研究进展

中华放射医学与防护杂志 2024年第1期44卷 65-71页

作者：曾丽晶夏煌陈钰昕林佩悦杨晶曾文艺李小波徐本华郑榕福建医科大学附属协和医院放疗科福建省肿瘤智能影像与精准放疗重点实验室福建省消化、血液系统与乳腺恶性肿瘤放射与治疗临床医学研究中心福州350001 福建医科大学医学影像学院福州350122

原发性或转移性脑部恶性肿瘤患者接受放射治疗时,会引起脑组织功能和形态学变化,导致放射性脑损伤,并且其发病机制尚无统一定论,现有的研究进展和治疗方案有待阐明和完善。本综述从血管损伤、炎症反应、神经元功能障碍、胶质细胞损伤以... 详细信息

原发性或转移性脑部恶性肿瘤患者接受放射治疗时,会引起脑组织功能和形态学变化,导致放射性脑损伤,并且其发病机制尚无统一定论,现有的研究进展和治疗方案有待阐明和完善。本综述从血管损伤、炎症反应、神经元功能障碍、胶质细胞损伤以及肠道微生物方面讨论放射性脑损伤的发病机制,以及治疗与预防的相关研究进展,旨在为放射性脑损伤的研究和临床诊治提供参考和理论依据。

关键词：放射性脑损伤放射治疗星形胶质细胞肠道微生物

The investigation on particulate organic carbon fluxes with disequilibria between thorium-234 and uranium-238 in the Prydz Bay,the Southern Ocean

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Acta Oceanologica Sinica 2008年第2期27卷 21-29页

作者： HE Jianhua MA Hao CHEN Liqi XIANG Baoqiang zeng Xianzhang YINMingduan zeng wenyi Key Laboratory of Global Change and Marine - Atmospheric Chemistry Third Institute of Oceanography State OceanicAdministration（SOA） Xiamen 361005 China Third Institute of Oceanography SOA Xiamen 361005 China Department of Engineering Physics Tsinghua University Beijing 100084 China Key Laboratory of Marine Science and Numerical Modeling First Institute of Oceanography SOA Qingdao 266061 China

Dissolved and particulate thorium-234, particulate organic carbon in the upper 150 m of water columns from five stations in the Prydz Bay, the Southern Ocean were determined during the 22nd Chinese National Antarctic Research Expedition （from November 2005 to March 2006 ）. The disequilibria between thorium-234 and its parent uranium-238 in upper layer was used to derive the averaged residence time of thorium-234, which decreased along with the latitude to the south and a minimum value, 1 - 8 d for particulate thorium-234 and 29 - 48 d for dissolved thorium-234, appeared at the medium latitude station, and the export fluxes of thorium-234 were calculated too and ＇a maximum value, 0. 35 -0. 63 Bq/（m^3 · d） for the particulate thorium-234 and 0. 44 -0. 65 Bq/ （m^3 ·d） for the dissolved thorium-234, appeared at the same station. The export fluxes of particulate organic carbon at different water columns were derived by two methods with irreversible scavenging model, and the averaged values were 104. 7 mmol/ （ m2 · d ）（ E method） and 120. 6 mmol/（ m2·d ）（ B method ）, respectively, indicating that a relatively high new production would exist in summer in the Prydz Bay where it will play a potential significant role in sequestering the absorption CO2 to deeper ocean.

关键词： POC fluxes disequilibria between thorium-234 and uranium-238 Prydz Bay Southern Ocean

An in-situ analysis and measurement of thorium-234,uranium isotopes in seawater

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Acta Oceanologica Sinica 2007年第3期26卷 73-83页

作者： zeng Xianzhang QIU Manhua YINMingduan zeng wenyi HE Jianhua WAN Xueguo CHEN Hengliang LI Jing TAN Baozeng Key laboratory of Global Change and Marine - Atmospheric Chemistry of State Oceanic Administration Third Institute of Ocea-nography State Oceanic Administration Xiamen 361005 China Third Institute of Oceanography State Oceanic Administration Xiamen 361005 China China National Nuclear Corporation Beijing Nuclear Instrument Factory Beijing 100020 China

A low-level β counting-or spectrum apparatus used for the detection of the β radiation of thorium-234 and α spectrum of thorium- 228 simultaneously and an easy operating procedure for the enrichment, radiochemical separating, sampling and measurement of thorium-234 and uranium-238 in the ocean are developed based on the requirements of analyzing export productivity in the eupho- ric zone via thorium-234 - uranium-238 radioactivity disequilibrium. The detecting efficiency both of 13 and α radiation is higher than 20%. The background of βradiation is less than 0. 5 min ^-1 , and the energy resolution of ct detector is better than 1%. Total recycle ratio of thorium-234 is about 75%. Using the above apparatus and procedure, the radioactivities of dissolved thorium-234 and uranium-238, particle thorium-234 and uranium-238 in seawater of the South China Sea, the Southern Ocean and the Arctic Ocean were analyzed.

关键词： ocean β counting-or spectrum apparatus radiochemical separating thorium-234 uranium-238

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变权决策中均衡函数均衡效果

系统工程理论与实践 2016年第3期36卷 712-718页

作者：李德清曾文艺军械工程学院基础部石家庄050003 北京师范大学信息科学与技术学院北京100875

讨论和型与积型可分解均衡函数的均衡效果.首先引入惩罚力度和激励力度两个概念,它们分别反映可分解惩罚式均衡函数和激励式均衡函数在变权决策过程中的均衡能力.然后从三个角度分析均衡函数在不同惩罚力度或激励力度下的均衡效果:一是... 详细信息

讨论和型与积型可分解均衡函数的均衡效果.首先引入惩罚力度和激励力度两个概念,它们分别反映可分解惩罚式均衡函数和激励式均衡函数在变权决策过程中的均衡能力.然后从三个角度分析均衡函数在不同惩罚力度或激励力度下的均衡效果:一是对变权向量的orness测度值的均衡效果;二是对因素权重的均衡效果;三是对综合决策值的均衡效果.结果表明,从可分解均衡函数的惩罚力度和激励力度出发,能很好地掌握均衡函数在变权决策中的作用规律,并且能为变权决策过程中如何选择合适的均衡函数从多方面提供考量准则.

关键词：变权综合可分解均衡函数惩罚力度激励力度本原函数

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逆行性植体周炎的诊断、病因与防治

中华口腔医学杂志 2022年第3期57卷 302-306页

作者：曾文奕杜宇中山大学光华口腔医学院·附属口腔医院口腔种植科·广东省口腔医学重点实验室广州510055 中山大学光华口腔医学院·附属口腔医院牙体牙髓病科·广东省口腔医学重点实验室广州510055

逆行性植体周炎(retrograde peri-implantitis,RPI)是一种较少见的种植修复治疗生物学并发症,近年有发病率逐渐增高的趋势。RPI的特征为种植体植入后尖端出现骨缺损,而冠方骨结合正常。由于RPI不一定有临床症状或指征,若种植修复治疗术... 详细信息

逆行性植体周炎(retrograde peri-implantitis,RPI)是一种较少见的种植修复治疗生物学并发症,近年有发病率逐渐增高的趋势。RPI的特征为种植体植入后尖端出现骨缺损,而冠方骨结合正常。由于RPI不一定有临床症状或指征,若种植修复治疗术后未进行定期影像学检查,较易发生漏诊,继而延误治疗时机且影响远期疗效。RPI常见致病因素包括邻牙根尖周病损、种植位点残留细菌及种植体尖端污染等,治疗方法则根据病变来源和严重程度选择。本文通过回顾文献总结关于RPI的诊断分类、病因病理以及预防治疗,为今后的临床决策提供参考。

关键词：牙种植植体周炎根尖周病诊断分类治疗

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基于数值拟合的区间值模糊推理算法

北京师范大学学报（自然科学版） 2008年第5期44卷 459-464页

作者：冯霜曾文艺北京师范大学数学科学学院数学与复杂系统教育部重点实验室北京100875 北京师范大学信息科学与技术学院北京100875

将数值拟合技术引入到区间值模糊推理中,提出一种基于数值拟合的区间值模糊双向推理算法.并给出3个应用实例来说明该算法的可行性.同时比较并证明了该算法的良好性质.

关键词：区间值模糊集合模糊集合数值拟合模糊推理

Contrast in Secondary Organic Aerosols between the Present Day and the Preindustrial Period:The Importance of Nontraditional Sources and the Changed Atmospheric Oxidation Capability

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Advances in Atmospheric Sciences 2024年第10期41卷 1936-1952+2092-2100页

作者： Yingchuan YANG wenyi YANG Xueshun CHEN Jiawen ZHU Huansheng CHEN Yuanlin WANG Wending WANG Lianfang WEI Ying WEI Qian YE Huiyun DU Zichen WU Zhe WANG Jie LI Xiaodong zeng Zifa WANG State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry Institute of Atmospheric Physics Chinese Academy of Sciences University of Chinese Academy of Sciences Chinese Academy of Environmental Planning International Center for Climate and Environment Sciences Institute of Atmospheric PhysicsChinese Academy of Sciences Institute of Urban Meteorology China Meteorology Administration Unit 93213 of PLA

Quantifying differences in secondary organic aerosols(SOAs) between the preindustrial period and the present day is crucial to assess climate forcing and environmental effects resulting from anthropogenic activities. The lack of vegetation information for the preindustrial period and the uncertainties in describing SOA formation are two leading factors preventing simulation of SOA. This study calculated the online emissions of biogenic volatile organic compounds(VOCs)in the Aerosol and Atmospheric Chemistry Model of the Institute of Atmospheric Physics(IAP-AACM) by coupling the Model of Emissions of Gases and Aerosols from Nature(MEGAN), where the input vegetation parameters were simulated by the IAP Dynamic Global Vegetation Model(IAP-DGVM). The volatility basis set(VBS) approach was adopted to simulate SOA formation from the nontraditional pathways, i.e., the oxidation of intermediate VOCs and aging of primary organic aerosol. Although biogenic SOAs(BSOAs) were dominant in SOAs globally in the preindustrial period, the contribution of nontraditional anthropogenic SOAs(ASOAs) to the total SOAs was up to 35.7%. In the present day, the contribution of ASOAs was 2.8 times larger than that in the preindustrial period. The contribution of nontraditional sources of SOAs to SOA was as high as 53.1%. The influence of increased anthropogenic emissions in the present day on BSOA concentrations was greater than that of increased biogenic emission changes. The response of BSOA concentrations to anthropogenic emission changes in the present day was more sensitive than that in the preindustrial period. The nontraditional sources and the atmospheric oxidation capability greatly affect the global SOA change.

关键词： anthropogenic and biogenic emissions IAP-AACM MEGAN secondary organic aerosol VBS

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模糊最小一乘线性回归

北京师范大学学报（自然科学版） 2008年第4期44卷 348-353页

作者：冯启磊曾文艺北京师范大学数学科学学院北京100875 北京师范大学信息科学与技术学院北京100875

针对输入和输出的模糊数据,根据最小一乘准则,提出了基于对称三角模糊数的模糊最小一乘线性回归模型,并将它转化成线性规划问题,应用Matlab进行求解,通过实例,并与Tanaka,Diamond,Kim-Bishu,Kao-Chyu,Nasrabadi,Chang等模型相比较,验证... 详细信息

针对输入和输出的模糊数据,根据最小一乘准则,提出了基于对称三角模糊数的模糊最小一乘线性回归模型,并将它转化成线性规划问题,应用Matlab进行求解,通过实例,并与Tanaka,Diamond,Kim-Bishu,Kao-Chyu,Nasrabadi,Chang等模型相比较,验证了我们的模型具有更优的拟合性和良好的稳定性.

关键词：模糊数据模糊最小一乘模糊线性回归参数估计

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广义梯形模糊数相似性度量的新方法及其应用

北京师范大学学报（自然科学版） 2015年第2期51卷 120-125页

作者：李俊红曾文艺北京师范大学信息科学与技术学院北京100875 河北师范大学数学与信息科学学院石家庄河北050024

针对模糊数相似度计算问题,提出一种新的基于广义梯形模糊数的相似度量方法,在保证度量有效性的前提下,降低相似度的计算复杂性,提高其区分度,扩大其适用范围.给出区分性、无效率和不合理率三个评价指标,以对不同相似度方法进行比较.实... 详细信息

针对模糊数相似度计算问题,提出一种新的基于广义梯形模糊数的相似度量方法,在保证度量有效性的前提下,降低相似度的计算复杂性,提高其区分度,扩大其适用范围.给出区分性、无效率和不合理率三个评价指标,以对不同相似度方法进行比较.实验结果表明新方法具有较好的性能.最后,通过基于DS证据理论的故障诊断实例说明所提方法的合理性和可用性.

关键词：相似度广义梯形模糊数模糊决策故障诊断 DS证据理论