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Surface Ozone in Jiuzhaigou National Park, Eastern Rim of the Qinghai-Tibet Plateau, China

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Journal of Mountain Science 2012年第5期9卷 687-696页

作者： QIAO xue TANG Ya Daniel JAFFE CHEN Pan xiao Weiyang DENG Guiping Department of Environment College of Architecture and EnvironmentSichuan UniversityNo 24South Section OneFirst Ring RoadChengdu 61o065China Department of Atmospheric Sciences University of Washington4o8Atmospheric Sciences-Geophysics(ATG)BuildingBox 351640SeattleWA 98195USA Jiuzhaigou Administration Bureau Jiuzhaigou County 623407Sichuan ProvinceChina

Located in southwestern China, Jiuzhaigou National Park is one of the most popular tourism destinations in China, famous for its unique aquatic ecosystems and beautiful forests. However, plants in the park may be at high ozone risk as a result of the intensive use of diesel tour buses in the park. In addition, Jiuzhaigou is close to a region with relatively high regional anthropogenic NOn emissions. During the growing season, also the peak season of tourism, we measured ozone concentration at two sites within the Park and these were： Jiuzhaigou Bureau （JB） and Long Lake （LL）. The results indicate that ozone concentrations were not high enough to cause foliar injury during the monitoring period, although the risk of ozone to plants was higher in spring than in summer and autumn. Diurnal ozone cycles at JB and LL displayed significantly higher ozone concentrations in the daytime than in the nighttime, suggesting photochemical production of ozone during the day and ozone deposition during the night as a result of the nocturnal boundary layer. In parallel with the seasonal change of background surface ozone in the Northern Hemisphere, maximum daily 8-h average ozone concentration （MDA8） and daily ozone concentration decreased from spring to autumn at the two sites. This temporal variation in Jiuzhaigou wasmost likely associated with the downward mixing of ozone-rich air from the free troposphere, because all the high-ozone events （MDA8 〉 70.0 ppb） were observed in spring and ozone-rich air from the free troposphere was the dominant cause. In summary, our data suggest that ozone concentrations in Jiuzhaigou were more affected by the regional-scale of background pattern in air quality and meteorological conditions than by local tourist activities.

关键词： Free troposphere Photochemicalproduction of ozone Surface ozone Mountainousregion Tourism

The Role of HIV Replicative Fitness in Perinatal Transmission of HIV

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Virologica Sinica 2011年第3期26卷 147-155页

作者： xue-qing Chen Chang Liu xiao-hong Kong （Laboratory of Medical Molecular Virology School of Medicine Nankai University Tianjin 300071 China）

Perinatal transmission of Human immunodeficiency virus(HIV),also called mother-to-child transmission(MTCT),accounts for 90% of infections in infants worldwide and occurs in 30%-45% of children born to untreated HIV-1 infected *** HIV-1 infected mothers,some viruses are transmitted from mothers to their infants while others are *** relationship between virologic properties and the pathogenesis caused by HIV-1 remains *** studies have demonstrated that one obvious source of selective pressure in the perinatal transmission of HIV-1 is maternal neutralizing *** studies have shown that viruses which are successfully transmitted to the child have growth advantages over those not transmitted,when those two viruses are grown ***,the higher fitness is determined by the gp120 protein of the virus *** suggests that the selective transmission of viruses with higher fitness occurred exclusively,regardless of transmission *** are many factors contributing to the selective transmission and HIV replicative fitness is an important one that should not be *** review summarizes current knowledge of the role of HIV replicative fitness in HIV MTCT transmission and the determinants of viral fitness upon MTCT.

关键词： Human immunodeficiency virus(HIV) Acquired immune deficiency syndrome(AIDS) Mother-to-child transmission(MTCT) Replicative fitness Gp120

Overexpression of Dickkopf-3 induces apoptosis through mitochondrial pathway in human colon cancer

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World Journal of Gastroenterology 2012年第14期18卷 1590-1601页

作者： Zi-rong Yang Wei-Guo Dong xiao-Fei Lei Meng Liu QiSheng Liu Department of Gastroenterology Renmin Hospital of Wuhan UniversityWuhan 430060Hubei ProvinceChina

AIM:To investigate the mechanisms of the biological roles of Dickkopf-3(Dkk-3) in cell invasion,survival and apoptosis in colon cancer ***:Three human colon cancer cell lines,i.e.,HT-29,LoVo and SW480,were *** of Dkk-3 induced by pEGFP-N1-Dkk-3-GFP plasmid in LoVo cells was performed using Lipofectamine 2000 *** transcription polymerase chain reaction and Western blotting were performed to determine the mRNA and protein expression levels of Dkk-3,*** proliferation assay,cell cycle analysis,hoechst 33258 assay and Matrigel invasion assay were performed on Dkk-3 overexpressing ***:The mRNA and protein expressions of Dkk-3 in HT-29(mRNA:0.06 ± 0.02,protein:0.06 ± 0.01) and LoVo(mRNA:0.07 ± 0.02,protein:0.07 ± 0.02) cells were significantly lower than that in SW480 cells(mRNA:0.92 ± 0.04,protein:0.69 ± 0.13;all P < 0.05),and the greatest levels of invasiveness wasin LoVo ***-3 overexpression inhibited the proliferation and invasion of LoVo cells and induced cell cycle arrest at G0/G1 phase and subsequent apoptosis,as indicated by increased chromatin condensation and fragments,upregulated Bax and cytochrome c protein,downregulated survivin and Bcl-2 protein,and the activation of caspase-3 and ***,Dkk-3 overexpression reduced the accumulation of cytosolic fraction of β-***:Dkk-3 overexpression induced apoptosis in human colon cancer possibly through the mitochondrial ***-3 may be involved in the Wnt/β-catenin signaling pathways in colon cancer.

关键词： Dickkopf-3 Overexpression Invasion Apotosis Colon cancer Mitochondria

Analytical solution to incident angle quasi-phase-matching engineering for second harmonic generation in a periodic-poled lithium niobate crystal

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Chinese Physics B 2024年第2期33卷 115-123页

作者：洪丽红邱雅婷李晓霓陈宝琴李志远 State Key Laboratory of High Field Laser Physics Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghai 201800China School of Physics and Optoelectronics South China University of TechnologyGuangzhou 510640China

Phase matching or quasi-phase matching(QPM)is of significant importance to the conversion efficiency of second harmonic generation(SHG)in artificial nonlinear crystals like lithium niobate(LN)crystal or microstructured nonlinear crystals like periodic-poled lithium niobate(PPLN)*** this paper,we propose and show that the incident angle of pump laser light can be harnessed as an alternative versatile tool to engineer QPM for high-efficiency SHG in a PPLN crystal,in addition to conventional means of period adjusting or temperature tuning.A rigorous model is established and analytical solution of the nonlinear conversion efficiency under the small and large signal approximation theory is obtained at different incident *** variation of phase mismatching and walk-off length with incident angle or incident wavelength are also *** simulations for a PPLN crystal with first order QPM structure are used to confirm our theoretical predictions based on the exact analytical solution of the general large-signal *** results show that the narrow-band tunable SHG output covers a range of 532 nm–552.8 nm at the ideal incident angle from 0°to 90°.This theoretical scheme,fully considering the reflection and transmission at the air-crystal interface,would offer an efficient theoretical system to evaluate the nonlinear frequency conversion and help to obtain the maximum SHG conversion efficiency by selecting an optimum incident wavelength and incident angle in a specially designed PPLN crystal,which would be very helpful for the design of tunable narrow-band pulse nanosecond,picosecond,and femtosecond laser devices via PPLN and other microstructured LN crystals.

关键词： nonlinear frequency conversion transmission reflection lithium niobate

国内药政改革背景下中小型合同研究生产组织的发展战略探索

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中国新药杂志 2024年第11期33卷 1089-1092页

作者：吴晓燕黄哲沈阳药科大学沈阳110179

通过研究当前国内药品管理相关制度,对国内合同研究生产组织(contract development manufacture organization,CDMO)的发展现状和问题进行分析,为中小型CDMO的发展战略提出建议。研究结果表明适合中小型CDMO的发展战略包括:选择特色化... 详细信息

通过研究当前国内药品管理相关制度,对国内合同研究生产组织(contract development manufacture organization,CDMO)的发展现状和问题进行分析,为中小型CDMO的发展战略提出建议。研究结果表明适合中小型CDMO的发展战略包括:选择特色化发展道路,打造高技术壁垒的平台;持续完善质量管理体系;引进和培养专业技术人才和管理人才;加强外部联盟与合作。

关键词：药品上市持有人制度合同研究生产组织发展战略药品研发药政改革

High throughput VLSI architecture for H.264/AVC context-based adaptive binary arithmetic coding(CABAC) decoding

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Journal of Zhejiang University-Science C(Computers and Electronics) 2013年第6期14卷 449-463页

作者： Kai HUANG De MA rong-jie YAN Hai-tong GE xiao-lang YAN Institute of VLSI Design Zhejiang University State Key Laboratory of Computer Science Institute of SoftwareChinese Academy of Sciences Hangzhou C-Sky Micro-System Company

Context-based adaptive binary arithmetic coding(CABAC) is the major entropy-coding algorithm employed in H.264/*** this paper,we present a new VLSI architecture design for an H.264/AVC CABAC decoder,which optimizes both decode decision and decode bypass engines for high throughput,and improves context model allocation for efficient external memory *** on the fact that the most possible symbol(MPS) branch is much simpler than the least possible symbol(LPS) branch,a newly organized decode decision engine consisting of two serially concatenated MPS branches and one LPS branch is proposed to achieve better parallelism at lower timing path cost.A look-ahead context index(ctxIdx) calculation mechanism is designed to provide the context model for the second MPS branch.A head-zero detector is proposed to improve the performance of the decode bypass engine according to UEGk encoding *** addition,to lower the frequency of memory access,we reorganize the context models in external memory and use three circular buffers to cache the context models,neighboring information,and bit stream,respectively.A pre-fetching mechanism with a prediction scheme is adopted to load the corresponding content to a circular buffer to hide external memory *** results show that our design can operate at 250 MHz with a 20.71k gate count in SMIC18 silicon technology,and that it achieves an average data decoding rate of 1.5 bins/cycle.

关键词： H.264/AVC Context-based adaptive binary arithmetic coding(CABAC) Decoder VLSI

Preliminary Research on Cd^(2+) Removal from Wastewater by Sphaerotilus Natans

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Chemical Research in Chinese Universities 2005年第6期21卷 654-657页

作者： QIN Yu-chun GUAN xiao-hui YIN rong WANG Li-wen WEI De-zhou School of Resources and Civil Engineering Northeastern University Shenyang 110004 P. R. China Department of Applied Chemistry Northeast Institute of Electric Power Engineering Jilin 132012 P. R. China Department of Common Courses Beihua University Jilin 132011 P. R. China

Influencing factors, such as the biomass concentration, pH value, temperature and time of adsorption on the removal of Cd^2＋ were investigated when Sphaerotilus natans was used as a biosorbent. The results show that Sphaerotilus natans has a significant effect on the adsorption of Cd^2＋. The process of adsorption will reach the equilibrium in 20 min. Temperature has no significant effect on the adsorption. The removal rate of Cd^2＋. can approach to 90% under the conditions of pH 5.5, the biomass mass concentration O. 6 g/L and the initial mass concentration of cadmium ≤20 mg/L. The maximum specific uptake is 1.9 mmol/g dry biomass . The adsorption was fitted with the Freundlich isotherm adsorption equation when the concentration of Cd^2＋ is in a range of 0--100 mg/L. HCl and EDTA can desorb Cd^2＋ from biomass effectively.

关键词： Sphaerotilus natans Cadmium ion Adsorption character Influencing factor

国内外谷子资源农艺、品质性状差异分析以及遗传多样性研究

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作物学报 2024年第10期50卷 2468-2482页

作者：薛亚鹏辛旭霞王若楠于筱菡刘少雄王瑞云刘敏轩山西农业大学农学院山西太谷030801 中国农业科学院作物科学研究所/作物基因资源与育种全国重点实验室北京100081

对新引进国外谷子资源的综合农艺性状、品质性状以及与国内地方品种的亲缘关系进行研究,为优异资源挖掘、利用提供数据参考。本研究以88份新引进谷子品种和152份国内地方品种为研究对象,对其开展田间农艺性状的调查,对收获后的种子进行... 详细信息

对新引进国外谷子资源的综合农艺性状、品质性状以及与国内地方品种的亲缘关系进行研究,为优异资源挖掘、利用提供数据参考。本研究以88份新引进谷子品种和152份国内地方品种为研究对象,对其开展田间农艺性状的调查,对收获后的种子进行品质测定,同时利用重测序获得的SNP标记开展亲缘关系分析。结果表明,数量性状在参试材料之间有显著的差异,遗传多样性丰富,遗传多样性指数H'≥2.00的性状有7个,数量性状综合评价排名前3的材料为来自山东省的半月硬(F=2.47)、来自英国的新引进种质Y-190(F=2.45)和来自山西省的大白谷I(F=2.38);质量性状差异不显著,遗传多样性指数H¢介于0.38~1.37之间;相关性分析显示除穗粗与千粒重呈现不显著负相关外,其余数量性状之间均呈现不同程度的正相关。品质测定结果显示各性状基本符合正态分布且在不同品种间存在差异,品质性状的遗传多样性指数H'介于1.65~2.05,粗蛋白和粗脂肪的遗传多样性最丰富(H'≥2.00);相关性分析显示,粗蛋白含量与粗脂肪含量、粗脂肪含量与粗纤维含量均呈现不显著负相关;淀粉含量与粗纤维含量、L*与b*均呈现显著的正相关。基于表型性状将参试材料划分为4类,且每个类群均存在表型特异性;基于SNP的进化树和群体结构分析表明不同品种间存在多样的亲缘关系,部分新引进种质与国内地方品种间存在较近的亲缘关系,不同材料间的具体的亲缘关系还需进一步研究。通过本研究对近几年新引进的国外资源的农艺性状、品质性状以及与国内资源的异同进行了全面的评价,为后续优异资源的利用、推广奠定了基础。

关键词：谷子农艺性状品质性状 SNP 亲缘关系

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Formation and capturing of nanoparticles in Cu-1wt.%Fe alloy melt during directional solidification process

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Journal of Iron and Steel Research International 2017年第4期24卷 411-415页

作者： Tao Wang xiao-hua Chen Guo-dong Shi Chang-rong Li Zi-dong Wang School of Materials Science and Engineering University of Science and Technology BeijingBeijing 100083China State Key Laboratory for Advanced Metals and Materials University of Science and Technology BeijingBeijing 100083China

A single crystal Cu-1wt.%Fe alloy with finely dispersed iron-rich nanoparticles which keep coherent interface with the copper matrix was prepared under directional *** of nanoparticles in the alloy melt was investigated by performing differential scanning calorimeter tests and designed water quenching experiment at a certain *** show that iron-rich nanoparticles are formed in the Cu-1wt.%Fe alloy melt before primaryα-Cu forms,which is not consistent with equilibrium phase *** that iron-rich nanoparticles are uniformly captured in the matrix was described,which is that numerous nanoparticles follow Brownian motions and are engulfed in the solidified matrix which makes it possible to form uniformly distributed nanoparticles reinforced single crystal Cu-1wt.%Fe alloy.

关键词： Single crystal Copper alloy Nanoparticle Coherent interface Brownian motion