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Inter-comparisons of VOC oxidation mechanisms based on box model:A focus on OH reactivity

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Journal of Environmental Sciences 2022年第4期34卷 286-296页

作者： Xiaoyun Yang bin yuan Zhe Peng Yuwen Peng Caihong Wu Suxia Yang Jin Li Min Shao Institute for Environmental and Climate Research Jinan UniversityGuangzhou 511443China Guangdong-Hongkong-Macao Joint Laboratory of Collaborative Innovation for Environmental Quality Guangzhou 511443China Department of Chemistry and Cooperative Institute for Research in Environmental Sciences University of ColoradoBoulderCO 80309USA

Volatile organic compounds(VOCs)oxidation processes play a very important role in atmospheric chemistry,and the chemical reactions are expressed in various manners in chemical *** gain an improved understanding of VOCs evolution during oxidation processes and evaluate the discrepancies of VOCs oxidation schemes among different mechanisms,we used the total VOC reactivity as a diagnostic and evaluated tool to explore the differences for six widely used chemical *** compared the total VOC reactivity evolution under high-NO_(x)xconditions for several sets of precursors,including n-pentane,toluene,ethene,isoprene and a mixture of 57 Photochemical Assessment Monitoring Stations(PAMS)species in a 0-D photochemical box ***-comparison of total VOC reactivity of individual precursor simulations showed discrepancies to different extent of the oxidation schemes among the studied mechanisms,which are mainly attributed to the different lumping approaches for organic *** PAMS simulation showed smaller discrepancy than individual precursor cases in terms of total VOC ***07 and RACM2 performances are found to better match the MCM for simulation of total VOC *** suggest that the performance in simulating secondary organic products,OH concentrations and NO_(x)concentrations are related to the OH reactivity discrepancies among various chemical *** in this study can be used in selection of chemical mechanisms to better model OH reactivity in different *** results in this study also provide directions to further improve the ability in modelling total VOC reactivity with the chemical mechanisms.

关键词： VOCs Box model Chemical mechanism Total VOC reactivity VOC oxidation

阿兹夫定片在健康成年及老年受试者中单次和多次给药的药代动力学研究

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中国临床药理学杂志 2024年第9期40卷 1316-1320页

作者：张宇刘小健鞠浩爽何斌源万元浩柴立维任乐阳吕敏贾亚强张微徐萍天津市第五中心医院Ⅰ期临床试验研究室天津300450 河南真实生物科技有限公司河南平顶山467000 有济(天津)医药科技有限公司天津300000 天津洛必塔医学研究有限公司天津300000

目的评价单次口服和多次口服阿兹夫定片在中国健康成年及老年受试者中的药代动力学特征及安全性。方法本研究采取开放、平行方案设计。试验分为2个试验组:健康成年受试者组和健康老年受试者组,分别入组12例受试者。入组的受试者首先进... 详细信息

目的评价单次口服和多次口服阿兹夫定片在中国健康成年及老年受试者中的药代动力学特征及安全性。方法本研究采取开放、平行方案设计。试验分为2个试验组:健康成年受试者组和健康老年受试者组,分别入组12例受试者。入组的受试者首先进行单次给药,空腹口服阿兹夫定片5 mg,经3 d清洗期后进入多次给药阶段,空腹口服阿兹夫定片5 mg·d^(-1),连续给药7 d。结果单次给予阿兹夫定片5 mg后,健康成年受试者C_(max),AUC_(0-∞)分别为(4.76±2.12)ng·mL^(-1),(6.53±2.20)ng·mL^(-1)·h,T_(max),t_(1/2)的中位数分别为0.75,1.87 h;健康老年受试者平均C_(max),AUC_(0-∞)分别为(6.40±3.25)ng·mL^(-1),(9.50±3.70)ng·mL^(-1)·h,T_(max),t_(1/2)的中位数分别为0.63,2.66 h。连续7 d给予阿兹夫定片5 mg后,健康成年受试者C_(max,ss),AUC_(0-∞,ss)分别为(3.26±1.61)ng·mL^(-1),(5.38±2.19)ng·mL^(-1)·h,T_(max,ss),t_(1/2,ss)的中位数分别为0.88,2.13 h;健康老年受试者平均C_(max,ss),AUC_(0-∞,ss)分别为(3.97±2.09)ng·mL^(-1),(6.71±3.26)ng·mL^(-1)·h,T_(max,ss),t_(1/2,ss)的中位数分别为0.75,2.56 h。单次给药后,健康老年人和健康成年人C_(max)、AUC_(0-t)和AUC_(0-∞)的几何均数比值及其90%置信区间分别为128.37%(88.23%~186.76%)、139.93%(105.42%~185.72%)、140.03%(106.33%~184.41%)。连续7 d给予阿兹夫定片5 mg,健康老年人和健康成年人C_(max,ss)、AUC_(0-t,ss)和AUC_(0-∞,ss)的几何均数比值及其90%置信区间分别为118.66%(80.83%~174.20%)、118.41%(83.60%~167.69%),118.95%(84.78%~166.89%)。结论单次及多次口服阿兹夫定片后,健康老年人与健康成年人相比,系统暴露均有所提高。健康老年人服用阿兹夫定片后,其不良事件和药物不良反应发生的种类、严重程度和发生率与健康成年人相比无明显差异,安全性耐受性良好。

关键词：阿兹夫定片老年受试者健康成年受试者药代动力学

Resource investment for DDoS attack resistant SDN: a practical assessment

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Science China(Information Sciences) 2023年第7期66卷 112-129页

作者： bin yuan Fan ZHANG Jun WAN Huan ZHAO Shui YU Deqing ZOU Qiangsheng HUA Hai JIN School of Cyber Science and Engineering Huazhong University of Science and Technology National Engineering Research Center for Big Data Technology and System Services Computing Technology and System Lab Hubei Engineering Research Center on Big Data Security Shenzhen Huazhong University of Science and Technology Research Institute School of Computer Science and Technology Huazhong University of Science and Technology Cluster and Grid Computing Lab School of Computer Science University of Technology Sydney

Software-defined networks(SDNs) present a novel network architecture that is widely used in various datacenters. However, SDNs also suffer from many types of security threats, among which a distributed denial of service(DDoS) attack, which aims to drain the resources of SDN switches and controllers,is one of the most common. Once the switch or controller is damaged, the network services can be *** defense schemes against DDoS attacks have been proposed from the perspective of attack detection;however, such defense schemes are known to suffer from a time consuming and unpromising accuracy, which could result in an unavailable network service before specific countermeasures are taken. To address this issue through a systematic investigation, we propose an elaborate resource-management mechanism against DDoS attacks in an SDN. Specifically, by considering the SDN topology, we leverage the M/M/c queuing model to measure the resistance of an SDN to DDoS attacks. Network administrators can therefore invest a reasonable number of resources into SDN switches and SDN controllers to defend against DDoS attacks while guaranteeing the quality of service(QoS). Comprehensive analyses and empirical data-based experiments demonstrate the effectiveness of the proposed approach.

关键词： SDN security DDoS attacks resource management queueing theory QoS

New Way to Synthesize DW286——a Novel Fluoronaphthyridone Antibacterial Agent

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Chemical Research in Chinese Universities 2011年第6期27卷 981-983页

作者： FENG Lian-shun LIU Ming-liang ZHANG Yi-bin GUO Hui-yuan Institute of Medicinal Biotechnology Chinese Academy of Medical Sciences and Peking Union Medical College Beijing 100050 P. R. China

A new route for the synthesis of DW286, 7-[3-（aminomethyl）-4-（methoxyimino）-3-methyltetrahy- dro-1H-1-pyrrolyl]-1-cyclopropyl-6-fluoro-4-oxo-1,4-dihydro[1,8]naphthyridine-3-carboxylic acid hydrochloric acid salt, is described. In the presence of benzadehyde, DW286 was prepared by the direct condensation of 7-chloro-1-cyclopropyl-6-fluoro-4-oxo-1,4-dihydro[1,8]naphthyridine-3-carboxylic acid with new pyrrolidine derivative 7 which could be obtained by routine reactions.

关键词： DW286 Benzadehyde Direct condensation

Analysis of causes of pain after kyphoplasty for osteoporotic vertebral compression fractures

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Chinese Medical Journal 2013年第11期126卷 2192-2194页

作者： CHEN Xiao-ming MA Hua-song WANG Meng YANG bin yuan Wei Department of Orthopaedics the People's Liberation Army 306Hospital Beijing 100101 China

For the treatment of osteoporotic vertebral compression fractures （OVCFs）, percutaneous kyphoplasty （PKP）enables rapid pain relief and spinal stabilization, as well as correction of kyphosis. Although serious complications such as pulmonary embolism and spinal cord and nerve damage may occur,1 recurrence of pain after PKP is unlikely to require medical attention. The present study analyzed the causes of post-operative residual pain by reviewing the clinical data of 16 from 121 patients with OVCFs who underwent PKP from August 2005 to April 2009. METHODS

关键词： osteoporosis compression fractures kyphoplasty

Effect of diabetes mellitus on long-term outcomes of surgical revascularization in patients with ischemic heart failure:a propensity score-matching study

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Chinese Medical Journal 2021年第10期134卷 1146-1151页

作者： Meng Liu Hua-Jun Zhang Han Song Nan Cheng yuan-bin Wu Rong Wang Department of Cardiovascular Surgery Institute of Cardiac SurgeryPLA General HospitalInstitute of Cardiac SurgeryBeijing 100853China Department of Health Service PLA General HospitalBeijing 100853China

Background:Diabetes mellitus(DM)is an important risk factor in the long-term outcomes of surgical ***,few studies have focused on patients with ischemic heart failure(IHF)and DM,and the results are *** study aimed to evaluate the effect of DM on the long-term outcomes of IHF patients undergoing coronary artery bypass grafting(CABG).Methods:In this propensity-matched study,data of IHF patients who underwent CABG in our hospital from January 2007 to December 2017 were *** a mean 73-month follow-up time,the patients were divided into two groups according to whether they had *** primary endpoint was all-cause death,and the secondary endpoint was a composite of all-cause death,stroke,recurrent myocardial infarction,and ***:There was no significant difference in all-cause mortality between the two groups(5.8%vs.4.1%,P=0.216).The incidence of main adverse cardiovascular and cerebrovascular events(MACCE)in the secondary endpoint was significantly higher in the DM group than that in the non-DM group(10.4%vs.8.1%,P=0.023).Conclusions:DM can negatively affect the long-term outcomes of IHF patients undergoing CABG by significantly increasing the overall incidence of MACCE,though the long-term survival does not show a significant difference between the DM and non-DM patients.

关键词： Coronary artery bypass grafting Diabetes mellitus Ischemic heart failure

Design and implementation of square Helmholtz coil for uniform magnetic field generation

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Journal of Southeast University(English Edition) 2019年第1期35卷 16-21页

作者： Wang Chao yuan bin Mao Junfa Zhang Shuang School of Electronic Information and Electrical Engineering Shanghai Jiao Tong UniversityShanghai 200240China College of Electronic Science and Engineering Jilin UniversityChangchun 130021China

In order to calibrate electrical instruments and generate a constant magnetic field, a novel design method for square Helmholtz coil is proposed. According to the superposition principle in electromagnetics, the theory of the square Helmholtz coil is established, and the design method is verified by Matlab calculation. Compared with conventional circular Helmholtz coil, the novel square one is with a larger uniform region. Simulation work is conducted in Maxwell, and the distribution of the magnetic field is obtained. The results demonstrate the validation of the applied calculation method of the proposed Helmholtz model. The space utilization rate η is used to make a comparison between the square and circular coils for the uniform region. The square Helmholtz coil is fabricated, the length of a single square coil is 1.5 m, and the amplitude of the magnetic field is controlled by the current. The GSM-19 T proton magnetometer is used to measure the amplitude of the magnetic field generated by the square Helmholtz coil. Experimental results indicate that a wide-range variable uniform magnetic field from 0 to 120 μT is generated in the center of Helmholtz coils.

关键词： proton magnetometer square Helmholtz coils space utilization rate uniform magnetic field

废机油残留物再生剂对老化沥青动态力学性能和组分迁移的影响

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材料导报 2024年第2期38卷 276-283页

作者：况栋梁马小军马晓燕袁斌侯俊鹏蔡军长安大学材料科学与工程学院西安710064 青海交通规划设计研究院有限公司西宁810000 甘肃路桥集团养护科技有限公司兰州730050 青海西互高速公路管理有限公司西宁810000

目前,再生沥青的研究主要集中在老化沥青性能的恢复上,而对老化后再生沥青性能变化的研究较少。本研究以自制的两种废机油残留物再生剂(REOB1、REOB2)对老化基质沥青进行再生,并对再生沥青进行短期老化(TFOT)和长期老化(PAV)。采用动态... 详细信息

目前,再生沥青的研究主要集中在老化沥青性能的恢复上,而对老化后再生沥青性能变化的研究较少。本研究以自制的两种废机油残留物再生剂(REOB1、REOB2)对老化基质沥青进行再生,并对再生沥青进行短期老化(TFOT)和长期老化(PAV)。采用动态剪切流变仪(DSR)和薄层棒状色谱仪(TLC-FID)分析再生沥青及其老化后的动态力学性能和化学组分变化情况。结果表明,两种REOB再生剂均能使老化基质沥青的性能恢复至原样沥青水平,并且REOB2再生剂与老化基质沥青的相容性优于REOB1再生剂;采用CAM模型对沥青复数模量、相位角主曲线进行拟合,并以原样沥青主曲线为参考,对老化与再生沥青拟合数据进行归一化处理,发现两种REOB再生剂均可以恢复老化基质沥青的复数模量和相位角。在二次老化过程中,RA+REOB再生沥青的归一化复模量指标(NCMI)在低频和中频范围内逐渐增大,即使经过长期老化,其复模量仍低于长期老化的基质沥青;而归一化相角指标(NPAI)在中频范围内的下降幅度明显大于低频范围和高频范围内的下降幅度,RA+REOB1再生沥青经过PAV老化后的NPAI低于长期老化后的基质沥青;随着老化程度的加深,RA+REOB再生沥青的化学组分从芳烃组分向胶质迁移,REOB1再生沥青经PAV老化后轻组分损失最大。

关键词：道路工程再生沥青再生剂二次老化动态力学性能化学组分

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非嗜酸性粒细胞哮喘诊治进展

重庆医科大学学报 2024年第1期49卷 1-7页

作者：张心悦邵子建练康吴德美袁斌吴芳唐兰芳浙江大学医学院附属儿童医院中医科、国家儿童健康与疾病临床医学研究中心杭州310005 南京中医药大学第一临床医学院、南京中医药大学附属医院儿科南京210028 浙江大学医学院附属儿童医院呼吸内科、国家儿童健康与疾病临床医学研究中心杭州310005

哮喘是全球最常见的慢性呼吸系统疾病之一,非嗜酸性粒细胞哮喘(non-eosinophilic asthma,NEA)是哮喘的一种特殊表型,其气道炎症的特征是细胞浸润以中性粒细胞为主,缺乏嗜酸性粒细胞。NEA发病与环境及宿主因素均有关,例如职业暴露、环境... 详细信息

哮喘是全球最常见的慢性呼吸系统疾病之一,非嗜酸性粒细胞哮喘(non-eosinophilic asthma,NEA)是哮喘的一种特殊表型,其气道炎症的特征是细胞浸润以中性粒细胞为主,缺乏嗜酸性粒细胞。NEA发病与环境及宿主因素均有关,例如职业暴露、环境污染、吸烟、感染和肥胖,上述风险因素单独或联合作用可以激活特定的细胞和分子途径,导致NEA发生。NEA的临床特征是对标准哮喘治疗的反应不佳,尤其是对吸入性皮质类固醇,导致疾病更严重和难以控制的哮喘。虽然NEA不是最普遍的哮喘表型,但重度哮喘患者中NEA比例高,其重要性不容忽视。本文就近年来NEA的流行病学现状、致病因素、发病机制和治疗现状作一综述。

关键词：哮喘非嗜酸性粒细胞型诊断治疗