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Air Pollution Exposure Based on Nighttime Light Remote Sensing and Multi-source Geographic Data in Beijing

Chinese Geographical Science 2023年第2期33卷 320-332页

作者： ZHANG Zheyuan WANG Jia XIONG Nina liang Boyi WANG zong Beijing Forestry University Beijing Key Laboratory of Precision ForestryBeijing 100083China Beijing Forestry University Institute of GISRS&GPSBeijing 100083China Beijing Municipal Institute of City Management Beijing 100028China Beijing Key Laboratory of Municipal Solid Wastes Testing Analysis and Evaluation Beijing 100028China

Air pollution is a problem that directly affects human health,the global environment and the climate.The air quality index(AQI)indicates the degree of air pollution and effect on human health;however,when assessing air pollution only based on AQI monitoring data the fact that the same degree of air pollution is more harmful in more densely populated areas is ignored.In the present study,multi-source data were combined to map the distribution of the AQI and population data,and the analyze their pollution population exposure of Beijing in 2018 was analyzed.Machine learning based on the random forest algorithm was adopted to calculate the monthly average AQI of Beijing in 2018.Using Luojia-1 nighttime light remote sensing data,population statistics data,the population of Beijing in 2018 and point of interest data,the distribution of the permanent population in Beijing was estimated with a high precision of 200 m×200 m.Based on the spatialization results of the AQI and population of Beijing,the air pollution exposure levels in various parts of Beijing were calculated using the population-weighted pollution exposure level(PWEL)formula.The results show that the southern region of Beijing had a more serious level of air pollution,while the northern region was less polluted.At the same time,the population was found to agglomerate mainly in the central city and the peripheric areas thereof.In the present study,the exposure of different districts and towns in Beijing to pollution was analyzed,based on high resolution population spatialization data,it could take the pollution exposure issue down to each individual town.And we found that towns with higher exposure such as Yongshun Town,Shahe Town and Liyuan Town were all found to have a population of over 200000 which was much higher than the median population of townships of51741 in Beijing.Additionally,the change trend of air pollution exposure levels in various regions of Beijing in 2018 was almost the same,with the peak value being in winter and the lowest value being in

关键词： air quality index(AQI) population pollution exposure nighttime light remote sensing Luojia-1 random forest

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肺动脉高压的药物治疗新进展

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现代预防医学 2012年第9期39卷 2294-2296+2303页

作者：余荷梁宗安四川大学华西医院重症医学科

随着对肺动脉高压(pulmonary hypertension,PH)发病机制研究的深入,其药物治疗也迅速发展,除了被批准的前列环素(PGI2)及其类似物,内皮素(ET)受体阻断剂和5型磷酸二酯酶(PDE-5)抑制剂外,许多新型药物也进入临床研究,成为肺动脉高压治疗... 详细信息

随着对肺动脉高压(pulmonary hypertension,PH)发病机制研究的深入,其药物治疗也迅速发展,除了被批准的前列环素(PGI2)及其类似物,内皮素(ET)受体阻断剂和5型磷酸二酯酶(PDE-5)抑制剂外,许多新型药物也进入临床研究,成为肺动脉高压治疗的新方向,本文就近年来肺动脉高压的药物治疗进展作一综述。

关键词：肺动脉高压药物治疗进展

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仿基因计算机的基因与免疫模型

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计算机工程与设计 2009年第17期30卷 3953-3956页

作者：朱洪亮余综华北计算技术研究所北京100083

将生物学中的基因遗传和免疫理论,同计算机信息安全理论相结合,在可信计算的基础上,研究能够提供自我保护、自主免疫、动态进化等特性的新一代计算机系统--仿基因计算机系统。结合公钥加密算法、单向散列算法和自然语言文本水印技术,对... 详细信息

将生物学中的基因遗传和免疫理论,同计算机信息安全理论相结合,在可信计算的基础上,研究能够提供自我保护、自主免疫、动态进化等特性的新一代计算机系统--仿基因计算机系统。结合公钥加密算法、单向散列算法和自然语言文本水印技术,对仿基因计算机的基因算法和免疫模型进行详细的阐述,并说明了该模型的可行性、安全性和有效性。

关键词：遗传免疫信息安全可信计算仿基因

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种下分层施用有机肥和化肥对花生产质量的影响

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中国土壤与肥料 2023年第8期 128-134页

作者：司贤宗张翔索炎炎李亮余辉河南省农业科学院植物营养与资源环境研究所河南郑州450002 正阳县花生研究所河南正阳463600

采用花生营养分层调控-起垄-播种一体机,通过研究花生种下分层施用有机肥与化肥对花生生长发育、养分积累、产量和品质、土壤理化性状的影响,旨在为砂姜黑土区夏花生微域土壤调理、高效施肥提供科学依据。结果表明,与有机肥和化肥撒施相... 详细信息

采用花生营养分层调控-起垄-播种一体机,通过研究花生种下分层施用有机肥与化肥对花生生长发育、养分积累、产量和品质、土壤理化性状的影响,旨在为砂姜黑土区夏花生微域土壤调理、高效施肥提供科学依据。结果表明,与有机肥和化肥撒施相比,种下施肥能改善花生农艺性状、提高经济性状,改善土壤理化性状,增加花生养分积累量,油酸含量平均增加1.94个百分点,产量平均增加554.0 kg/hm^(2),增产11.2%,其中,花生种下5和8 cm分层施用有机肥600 kg/hm^(2)和化肥600 kg/hm^(2)产量最高,为5759.4 kg/hm^(2)。花生种下5和8 cm分层施用有机肥和化肥的产量比种下5 cm同层施用有机肥和化肥的产量平均增加175.7 kg/hm^(2),平均增产3.3%,油酸含量平均增加0.89个百分点。化肥减施25%时,花生种下施用有机肥和化肥比有机肥和化肥撒施产量平均增加258.1~419.4 kg/hm^(2),平均增产5.2%~8.5%,油酸含量平均增加0.75~1.71个百分点,其中花生种下5和8 cm分层施用有机肥和化肥的增产提质效果最好。总之,花生种下5和8 cm分层施用有机肥600 kg/hm^(2)和化肥450 kg/hm^(2),与撒施有机肥600 kg/hm^(2)和化肥600 kg/hm^(2)相比,化肥减施25%,花生增产419.4 kg/hm^(2),增产8.5%,能实现有机肥和化肥协同增效,达到化肥减施和大面积均衡增产的目的,应在夏花生主产区推广应用。

关键词：花生种下分层施用有机肥化肥产质量

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Sphenoid wing meningioma en plaque： report of 37 cases

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Chinese Medical Journal 2009年第20期122卷 2423-2427页

作者： LI Yong SHI Ji-tong AN yu-zhi ZHANG Tian-ming FU Ji-di ZHANG Jia-liang ZHAO Ji-zong Department of Neurosurgery Beijing Tongren Hospital Capital Medical University Beijing 100730 China. Department of Ophthalmology Beijing Tongren Hospital Capital Medical University Beijing 100730 China. Department of Neurosurgery Beijing Tiantan Hospital Capital Medical University Beijing 100050 China

Background Sphenoid wing meningioma en plaque is a special morphological subgroup of intracranial meningiomas, defined by a carpet-like, soft tissue component that infiltrates the dura and invades the sphenoid wing and orbit associated with a significant hyperostosis. This report summarized our experiences in 37 patients with sphenoid wing meningioma en plaque who had been treated with transcranio-orbital approach surgery. Methods A retrospective study was made on clinical manifestations, neuroradiological features, and operative techniques in 37 patients undergoing transcranio-orbital approach from Sep. 1998 to Apr. 2009. Patients ages： 16 years to 67 years, 45.5 years in average; sex： 15 males, 22 females. Chief complaints were progressive proptosis and visual acuity deficits. All patients were operated on using a fronto-temporal approach with orbital decompression. The extent of tumor resection and postoperative complications were investigated. Results Simpson grade Ⅱ resection was achieved in 9 patients, Simpson grade Ⅲ in 22 patients and Simpson grade Ⅳ in 6 patients. Pathological examination showed 27 （73%） patients were meningothelial meningiomas. After surgery, proptosis improved in all patients, visual acuity improved in 18 patients （69%）. Temporary ophthalmoplegia was found in 8 patients, cerebrospinal fluid leak was found in 1 patient. Duration of follow up was from 3 months to 9 years, tumor recurred in 7 patients, and 5 patients underwent second surgery, including two trans-nasal endoscopic surgeries to resect sphenoid sinus-involved tumor. There were no operation-related deaths or other significant complications. Conclusions Sphenoid wing meningioma en plaque, mainly meningothelial meningiomas, are more likely to produce adjacent hyperostosis and have characteristic radiological appearances. All the hyperostosis bone of the great wing of sphenoid bone should be removed to prevent recurrence. Extensive tumor removal with bony decompression at the orbital apex can produce satisfactory cosmetic and fun

关键词： meningioma sphenoid bone neurosurgical procedures

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岩体裂隙粗糙度表征及其对裂隙渗流特性的影响

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岩土力学 2023年第6期44卷 1585-1592页

作者：甘磊刘玉张宗亮沈振中马洪影河海大学水利水电学院江苏南京210098 中国电力建设集团有限公司北京100048

岩体裂隙粗糙程度对裂隙渗流特性的影响显著。利用三维光学扫描系统获取岩体裂隙面点云数据,结合SURFER和GEOMAGIC STUDIO等软件计算裂隙面节理粗糙度系数JRC和表面粗糙比率Rs,建立JRC与Rs的定量关系,开展应力、渗流和化学耦合作用下石... 详细信息

岩体裂隙粗糙程度对裂隙渗流特性的影响显著。利用三维光学扫描系统获取岩体裂隙面点云数据,结合SURFER和GEOMAGIC STUDIO等软件计算裂隙面节理粗糙度系数JRC和表面粗糙比率Rs,建立JRC与Rs的定量关系,开展应力、渗流和化学耦合作用下石灰岩裂隙渗流试验,研究JRC和Rs对粗糙裂隙渗流特性的影响。结果表明:JRC与Rs呈对数函数关系,其平方根R2为0.9128,该表征公式与裂隙渗流试验结果最大相对误差MRE、平均绝对误差MAE和均方根误差RMSE分别为6.93%、0.34和0.27。JRC与渗流量、稳定期渗透率分别呈二次函数和对数函数关系,Rs和各参数的拟合关系与JRC相同。JRC值越大,渗流量和渗透率越小,且三场耦合作用下裂隙面JRC和Rs值均有所增大。该表征方法可用于岩体裂隙面粗糙度估算,由裂隙面JRC值可预测该裂隙渗流量和稳定时刻渗透率。

关键词：岩体裂隙粗糙度三维扫描节理粗糙度系数渗流量渗透率

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On Equivalence of Simple Closed Curves in Flat Surfaces

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Acta Mathematica Sinica,English Series 2014年第11期30卷 1827-1832页

作者： zong liang SUN Department of Mathematics Shenzhen University

By explicit constructions,we give direct proofs of the following results： for any distinct homotopy classes of simple closed curves α and β in a closed surface of genus g 〉1,there exist a hyperbolic structure X and a holomorphic quadratic differential q on X such that lX（α） = lX（β）,extX（α） = extX（β） and lq（α） = lq（β）,where lX（·）,extX（·） and lq（·） are the hyperbolic length,the extremal length and the quadratic differential length respectively.These imply that there are no equivalent simple closed curves in hyperbolic surfaces or in flat surfaces.

关键词： Hyperbolic metric quadratic differential metric simple closed curve

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Robust twin-field quantum key distribution through sending or not sending

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National Science Review 2023年第4期10卷 76-85页

作者： Cong Jiang zong-Wen yu Xiao-Long Hu Xiang-Bin Wang Jinan Institute of Quantum Technology State Key Laboratory of Low Dimensional Quantum Physics Department of Physics Tsinghua University Data Communication Science and Technology Research Institute School of Physics State Key Laboratory of Optoelectronic Materials and Technologies Sun Yat-sen University Shanghai Branch CAS Center for Excellence and Synergetic Innovation Center in Quantum Information and Quantum Physics University of Science and Technology of China Shenzhen Institute for Quantum Science and Engineering and Physics Department Southern University of Science and Technology Frontier Science Center for Quantum Information

The sending-or-not-sending(SNS) protocol is one of the most major variants of the twin-field(TF)quantum key distribution(QKD) protocol and has been realized in a 511-km field fiber, the farthest field experiment to date. In practice, however, all decoy-state methods have unavoidable source errors, and the source errors may be non-random, which compromises the security condition of the existing TF-QKD protocols. In this study, we present a general approach for efficiently calculating the SNS protocol’s secure key rate with source errors, by establishing the equivalent protocols through virtual atenuation and the tagged model. This makes the first result for TF QKD in practice where source intensity cannot be controlled exactly. Our method can be combined with the two-way classical communication method such as active odd-parity pairing to further improve the key rate. The numerical results show that if the intensity error is within a few percent, the key rate and secure distance only decrease marginally. The key rate of the recent SNS experiment in the 511-km field fiber is still positive using our method presented here, even if there is a ±9.5% intensity fluctuation. This shows that the SNS protocol is robust against source errors.

关键词： quantum information quantum key distribution sending or not sending twin field source error

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Ruthenium complexes targeting mitochondria and nuclei sequentially

Ruthenium complexes targeting mitochondria and nuclei sequen...

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第十一届全国化学生物学学术会议

作者： Wen-Jin Wang Cai-ping Tan yu-jian Wang liang-nian Ji zong-wan Mao MOE Key Laboratory of Bioinorganic and Synthetic Chemistry School of Chemistry and Chemical EngineeringSun Yat-sen University

Owing to the role in the regulation of fundamental cellular functions,mitochondria have always been a crucial targets for cancer treatment. Herein,five ruthenium complexes were designed and synthesized,among which Ru2,Ru3 and Ru5 containing triphenylphosphine as mitochondria targeting moiety.Accordingly,these complexes displayed high cytotoxicity to all tested tumor cell lines.Ru5 shows the lowest IC50 value(0.51 μM) against human lung cancer A549 cells,which is almost twenty-fold lower than the IC value obtained in human normal cells.Confocal imaging reveals that Ru2,Ru3,Ru5 was sequestered in mitochondria at first 8 h,and then they distributed from mitochondria to nucleus with the accumulation of mitochondrial damage.Whereas the complexes Ru1 and Ru4 dispersed in cytoplasm throughout the imaging assay.Our results suggest that mitochondria may act as a switch for cell nucleus membrane permeability,the damage of mitochondria can result in the changes of nucleus’ permeability.

关键词： Mitochondria Nucleus,Migration,Ruthenium complexes

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血液净化室护士职业压力及应对

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系统医学 2016年第3期1卷 14-16页

作者：梁宗槟梁宗桦于荣伊犁州奎屯医院血液净化室新疆奎屯833200 新疆维吾尔自治区人民医院胃肠外科新疆乌鲁木齐830000 伊犁州奎屯医院肾病科新疆奎屯833200

目的分析血液净化室护士职业压力相关因素和应对策略。方法对该院2014年5月—2015年10月在血液净化室工作的8名护士的职业压力状况进行分析,总结相关影响因素,并提出具体应对策略。结果该组8名护士,实施应对策略前后,重度职业压力所占... 详细信息

目的分析血液净化室护士职业压力相关因素和应对策略。方法对该院2014年5月—2015年10月在血液净化室工作的8名护士的职业压力状况进行分析,总结相关影响因素,并提出具体应对策略。结果该组8名护士,实施应对策略前后,重度职业压力所占比重分别为25.0%、0.0%,对当前工作不满意所占比重分别为50.0%、12.5%,比较差异有统计学意义(P<0.05);分析认为职业压力大与工作量大、工作环境差、职业危险系数高和护患关系紧张等因素有关。结论职业压力直接影响到净化室护士身心健康以及血液净化工作质量,有必要改善工作环境,合理安排工作时间,并对净化室护士进行专业培训,使其能够以良好的身心状态投入到工作中。

关键词：血液净化护士职业压力因素策略

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