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基于对称双环嵌套管的低损耗弱耦合六模空芯负曲率光纤

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物理学报 2024年第7期73卷 90-103页

作者：惠战强刘瑞华高黎明韩冬冬李田甜巩稼民西安邮电大学电子工程学院西安710121 西安市微波光子与光通信技术重点实验室西安710121

本文设计了一种具有对称双环嵌套管结构的新型低损耗少模空芯负曲率光纤,该光纤支持LP_(01),LP_(11),LP_(21),LP_(02),LP_(31a),LP_(31b)共6种纤芯模式.所设计的光纤以SiO(_2)作为基底材料,采用特殊的对称双环嵌套结构将包层区域进行划... 详细信息

本文设计了一种具有对称双环嵌套管结构的新型低损耗少模空芯负曲率光纤,该光纤支持LP_(01),LP_(11),LP_(21),LP_(02),LP_(31a),LP_(31b)共6种纤芯模式.所设计的光纤以SiO(_2)作为基底材料,采用特殊的对称双环嵌套结构将包层区域进行划分,能够有效地减小纤芯模式与包层模式的耦合.使用有限元法对该少模空芯负曲率光纤的结构参数进行优化,并分析了纤芯各个模式的限制损耗和弯曲损耗.仿真结果表明,所提出的少模空芯负曲率光纤能够同时支持弱耦合的6种纤芯模式独立传输(相邻模式间的有效折射率差均大于10~(–4),有效地避免了纤芯内模式间的耦合).在400 nm带宽(1.23—1.63μm,覆盖O,E,S,C,L波段)范围内,纤芯中的6个模式均保持低损耗稳定传输.各模式限制损耗在1.4μm处达到最低,其中基模LP_(01)模式的限制损耗最低,为4.3×10^(–7)d B/m.此外,当弯曲半径为7 cm时,各模式在一定工作波长范围内均保持低弯曲损耗传输.公差分析表明,当结构参数偏移±1%时,该少模空芯负曲率光纤仍然可以保持低损耗弱耦合的传输特性.

关键词：空芯负曲率光纤少模光纤限制损耗弯曲损耗

Impact of Temperature on Mortality in Three Major Chinese Cities

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Biomedical and Environmental Sciences 2014年第7期27卷 485-494页

作者： ZHANG Jing li tian tian TAN Jian Guo HUANG Cun Rui KAN Hai Dong School of Public Health Key Laboratory of Public Health Safety of Ministry of EducationFudan University Institute of Environmental Health and Related Product Safety China Center for Disease Control and Prevention Shanghai Key Laboratory of Meteorology and Health Shanghai Meteorological InstituteSMB School of Public Health and Institute of Health and Biomedical Innovation Queensland University of Technology Research Institute for the Changing Global Environment and Fudan Tyndall Centre Fudan University Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention Fudan University

Objective To study the relation between temperature and mortality by estimating the temperature-related mortality in Beijing, Shanghai, and Guangzhou. Methods Data of daily mortality, weather and air pollution in the three cities were collected. A distributed lag nonlinear model was established and used in analyzing the effects of temperature on mortality. Current and future net temperature-related mortality was estimated. Results The association between temperature and mortality was J-shaped, with an increased death risk of both hot and cold temperature in these cities. The effects of cold temperature on health lasted longer than those of hot temperature. The projected temperature-related mortality increased with the decreased cold-related mortality. The mortality was higher in Guangzhou than in Beijing and Shanghai. Conclusion The impact of temperature on health varies in the 3 cities of China, which may have implications for climate policy making in China.

关键词： Climate change Temperature Mortality Time-series

Willingness to Pay for Measures of Managing the Health Effects of Heat Wave in Beijing,China:a Cross-sectional Survey

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Biomedical and Environmental Sciences 2016年第9期29卷 628-638页

作者： ZHANG Yi CHEN Chen BAN Jie ZHAO Jin Hui XU Dan Dan ZHU Peng Fei li tian tian Department of Environmental Health Risk Assessment Institute for Environmental Health and Related Product Safety Chinese Center for Disease Control and Prevention Institute of Environmental Health Beijing Center for Diseases Prevention and Control

Objective There are evidences that heat wave events cause deaths and emergency cases. This article used the contingent valuation method to find the willingness to pay for the protective measures and investigated the factors that influence the willingness to pay. Methods A cross-sectional face-to-face household survey was completed by 637 urban long-term residents and 591 rural long-term residents aged 15-79 in Beijing, China. Binary logistic regression was used to identify factors that influenced the payment rate or payment amount for the protective measures, including independent variables for district, gender, age, education, income, air conditioner ownership, heat wave experience, and chronic non-communicable disease. Results The payment rate was 41.1% for protective measures provided by the government and 39.5% by measures provided by the market. Most of the respondents were willing to pay 40 CNY per capita annually for measures provided by the government or the market. The factors influencing willingness to pay were district, gender, income, air conditioner ownership, heat wave experience, and chronic non-communicable disease. Conclusion Protective measures for heat waves need to be provided immediately. More attention should be paid to the situation of vulnerable groups, such as people who live in urban areas, those without air conditioning, and those who have experienced a heat wave in the past.

关键词： Heat wave Protective measure Willingness to pay Influencing factor

Assessing Heat-related Mortality Risks in Beijing,China

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Biomedical and Environmental Sciences 2012年第4期25卷 458-464页

作者： li tian tian GAO Yan lin WEI Zai Hua WANG Jing GUO Ya Fei liU Fan liU Zhao Rong CHENG Yah li Institute of Environmental Health and Related Product Safety Chinese Center for Disease Control and PreventionBeijing 100050China Beijing Municipal Center for Disease Control and Prevention Beijing 100013China College of Environmental Sciences and Engineering Peking UniversityBeo'ing 100871China Center for Atmosphere Watch and Services Chinese Academy of Meteorological SciencesKey Laboratory for Atmospheric ChemistryCMABeijing 100081China

Objective To obtain the exposure-response relationship for temperature and mortality, and assess the risk of heat-related premature death. Methods A statistical model was developed using a Poisson generalized linear regression model with Beijing mortality and temperature data from October 1st, 2006 to September 30th, 2008. We calculated the exposure-response relationship for temperature and mortality in the central city, and inner suburban and outer suburban regions. Based on this relationship, a health risk model was used to assess the risk of heat-related premature death in the summer （June to August） of 2009. Results The population in the outer suburbs had the highest temperature-related mortality risk. People in the central city had a mid-range risk, while people in the inner suburbs had the lowest risk. Risk assessment predicted that the number of heat-related premature deaths in the summer of 2009 was 1581. The city areas of Chaoyang and Haidian districts had the highest number of premature deaths. The number of premature deaths in the southern areas of Beijing （Fangshan, Fengtai, Daxing, and Tongzhou districts） was in the mid-range. Conclusion Ambient temperature significantly affects human mortality in Beijing. People in the city and outer suburban area have a higher temperature-related mortality risk than people in the inner suburban area. This may be explained by a temperature-related vulnerability. Key words： Temperature; Mortality; Premature death; Health risk; Generalized linear regression model; Climate change

关键词： Temperature Mortality Premature death Health risk Generalized linear regression model Climate change

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国际原油价格对中国通货膨胀的非线性冲击

价格月刊 2024年第2期 38-48页

作者：张源野叶阿忠李田田福州大学经济与管理学院福建福州350108

为更好了解国际油价冲击下的通胀风险,分别以国际原油价格、PPI和CPI为门槛变量,使用门槛向量自回归模型与广义脉冲响应函数分析了国际原油价格波动对中国PPI和CPI的冲击。研究发现:国际原油价格波动对中国的PPI和CPI有显著影响,且影响... 详细信息

为更好了解国际油价冲击下的通胀风险,分别以国际原油价格、PPI和CPI为门槛变量,使用门槛向量自回归模型与广义脉冲响应函数分析了国际原油价格波动对中国PPI和CPI的冲击。研究发现:国际原油价格波动对中国的PPI和CPI有显著影响,且影响程度和方向取决于国际原油价格、PPI和CPI所处的门槛区间。当国际原油价格处于不同水平时,国际油价冲击造成的影响各有不同。当通货膨胀处于较高水平时,国际油价冲击对通货膨胀造成的影响较大,反之,则影响较小。此外,国际原油价格冲击对通货膨胀的影响具有非对称性,但国际油价上涨造成的影响并没有总是大于下跌冲击。

关键词：门槛向量自回归广义脉冲响应国际原油价格 PPI CPI

Projections of Temperature-related Non-accidental Mortality in Nanjing, China

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Biomedical and Environmental Sciences 2019年第2期32卷 134-139页

作者： SUN Qing Hua Radley M.Horton Daniel A.Bader Bryan Jones ZHOU lian li tian tian National Institute of Environmental Health Chinese Center for Disease Control and Prevention Center for Climate Systems Research Columbia University City University of New York Institute for Demographic Research Jiangsu Provincial Center for Disease Control and Prevention

The health effects of climatic changes constitute an important research area, yet few researchers have reported city-or region-specific projections of temperature-related deaths based on assumptions about mitigation and adaptation. Herein, we provide quantitative projections for the number of additional deaths expected in the future.

关键词： RCP China SSP

“三子水剂”外洗治疗女阴瘙痒症临床疗效观察

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广州中医药大学学报 2024年第2期41卷 360-365页

作者：张艺王萍李田田北京市回民医院皮肤科北京100054 首都医科大学附属北京中医医院皮肤科北京100010 首都医科大学附属北京中医医院疮疡血管外科北京100010

【目的】观察“三子水剂”外洗治疗女阴瘙痒症(pruritus vulvae,PV)的临床疗效。【方法】将60例湿热下注型女阴瘙痒症患者随机分为对照组和试验组,每组各30例。对照组给予皮肤康洗液外洗治疗,试验组给予“三子水剂”外洗治疗。7 d为1个... 详细信息

【目的】观察“三子水剂”外洗治疗女阴瘙痒症(pruritus vulvae,PV)的临床疗效。【方法】将60例湿热下注型女阴瘙痒症患者随机分为对照组和试验组,每组各30例。对照组给予皮肤康洗液外洗治疗,试验组给予“三子水剂”外洗治疗。7 d为1个疗程,连续治疗4个疗程。观察2组患者治疗前后瘙痒程度、瘙痒频率及继发皮损等症状评分及皮肤病生活质量指数(DLQI)评分的变化情况,并评价2组患者的临床疗效和安全性。【结果】(1)疗效方面,治疗4周后,试验组的总有效率和愈显率分别为96.67%(29/30)、86.67%(26/30),对照组分别为90.00%(27/30)和63.34%(19/30);组间比较,试验组的愈显率明显高于对照组,差异有统计学意义(P0.05)。(2)症状评分方面,治疗后,2组患者的瘙痒程度、瘙痒频率、继发皮损等症状评分均较治疗前降低(P<0.05),且试验组对瘙痒程度、瘙痒频率、继发皮损等症状评分的降低作用均明显优于对照组,差异均有统计学意义(P<0.05)。(3)生活质量方面,治疗后,2组患者的DLQI评分均较治疗前明显降低(P<0.01),且试验组对DLQI评分的降低作用明显优于对照组,差异有统计学意义(P<0.05)。(4)安全性方面,治疗期间,2组患者均未出现外阴皮肤不适及过敏反应,且均未发现血常规、肝功能及肾功能等安全性指标的异常变化,具有较高的安全性。【结论】“三子水剂”外洗治疗女阴瘙痒症,具有安全性高、疗效好的特点,能够有效减轻患者瘙痒程度,降低瘙痒频率,缓解继发皮损,有利于提高患者生活质量。

关键词：三子水剂女阴瘙痒症湿热下注型临床疗效生活质量安全性

左甲状腺素钠片治疗妊娠合并亚临床甲状腺功能减退症的效果及对甲状腺激素水平、妊娠结局及子代生长发育的影响

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生殖医学杂志 2024年第7期33卷 900-906页

作者：黄启玉李甜甜荆门市人民医院产科荆门448000

目的探讨左甲状腺素钠片(LT_(4))治疗妊娠合并亚临床甲状腺功能减退症(亚临床甲减)的效果及对甲状腺激素水平、妊娠结局及子代生长发育的影响。方法回顾性选取2020年7月至2022年1月于我院就诊、定期产检及分娩的120名妊娠期亚临床甲... 详细信息

目的探讨左甲状腺素钠片(LT_(4))治疗妊娠合并亚临床甲状腺功能减退症(亚临床甲减)的效果及对甲状腺激素水平、妊娠结局及子代生长发育的影响。方法回顾性选取2020年7月至2022年1月于我院就诊、定期产检及分娩的120名妊娠期亚临床甲减孕妇为研究对象,依据其是否接受LT_(4)治疗情况,分为LT_(4)组(n=68)和非LT_(4)组(n=52),其中LT_(4)组依据血清促甲状腺激素(TSH)水平给与维持剂量(50~200μg/d) LT_(4)治疗至分娩结束,非LT_(4)组接受常规治疗干预。另选取同期于我院定期产检及分娩的健康孕妇50例作为对照组。比较3组基线状态及分娩前甲状腺激素水平、分娩方式、妊娠结局以及新生儿24 h内与出生后第6个月的甲状腺功能参数[游离甲状腺素(FT_(4))、游离三碘甲状腺原氨酸(FT3)、总三碘甲状腺原氨酸(TT3)、总甲状腺素(TT_(4))水平]以及生长发育指标,并统计治疗期间不良反应。结果 (1)相较于基线状态,LT_(4)组与非LT_(4)组分娩前TSH水平均显著降低(P0.05),但非LT_(4)组早产发生率显著高于对照组和LT_(4)组(P0.05)。(4)出生后6个月,非LT_(4)组身长、体重和端坐时间显著低于对照组与LT_(4)组(P0.05)。治疗期间,3组间不良反应发生率比较无显著性差异(P>0.05)。结论 LT_(4)治疗妊娠合并亚临床甲减效果显著,对改善孕妇甲状腺功能与妊娠结局、促进胎儿正常发育方面有一定助益,且安全性高,值得推荐。

关键词：妊娠合并亚临床甲减左甲状腺素钠片甲状腺激素妊娠结局

幽门螺杆菌感染对胃癌患者NF-κB/NLRP3信号通路和炎性因子的影响

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中华医院感染学杂志 2024年第3期34卷 361-365页

作者：韩静王柏清王珏磊李甜甜孙光斌天津市第五中心医院消化内科天津300450

目的探讨幽门螺杆菌(Hp)感染对胃癌患者单个核细胞核因子κB(NF-κB)/Nod样受体蛋白3(NLRP3)信号通路和炎性因子的影响.方法选取2020年6月-2023年1月天津市第五中心医院收治的49例Hp阳性胃癌患者为感染组,选择同期Hp阴性的47例胃癌患者... 详细信息

目的探讨幽门螺杆菌(Hp)感染对胃癌患者单个核细胞核因子κB(NF-κB)/Nod样受体蛋白3(NLRP3)信号通路和炎性因子的影响.方法选取2020年6月-2023年1月天津市第五中心医院收治的49例Hp阳性胃癌患者为感染组,选择同期Hp阴性的47例胃癌患者为对照组;采用酶联免疫吸附法检测患者血清炎性因子白细胞介素-1β(IL-1β)、IL-18、肿瘤坏死因子-α(TNF-α)、半胱氨酸天冬氨酸蛋白-1(Caspase-1)的水平;分别采用荧光定量聚合酶链式反应(PCR)以及Western blot方法检测NF-κB p56、NLRP3、Caspase-1三个基因mRNA以及蛋白表达水平.结果感染组外周血炎性因子IL-1β、IL-18、TNF-α、Caspase 1水平均高于对照组,外周血单个核细胞中NF-κB p56 mRNA、NLRP3 mRNA、Caspase-1 mRNA表达量与蛋白相对表达量高于对照组(P<0.05);感染组、对照组Ⅲ期患者NF-κB p56、NLRP3、Caspase-1蛋白表达量均高于对照组Ⅰ~Ⅱ期,蛋白表达量随着病理分期增加而上升(P<0.05).结论Hp感染能促进胃癌患者NF-κB/NLRP3信号通路的活化程度及IL-1β、IL-18等炎性因子的释放,与胃癌的发生密切相关.

关键词：幽门螺杆菌胃癌核因子κB Nod样受体家族蛋白3 半胱氨酸天冬氨酸蛋白-1 白细胞介素-1β