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Peat humification-and δ^(13)C_(cellulose)-recorded warm-season moisture variations during the past 500 years in the southern Altai Mountains within northern Xinjiang of China

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Journal of Mountain Science 2017年第11期14卷 2200-2211页

作者： ZHANG Dong-liang YANG Yun-peng lan Bo Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences University of Chinese Academy of Sciences School of Environmental and Chemical Engineering Chongqing Three Gorges University

To predict future spatio-temporal patterns of climate change, we should fully understand the spatio-temporal patterns of climate change during the past millennium. But, we are not yet able to delineate the patterns because the qualities of the retrieved proxy records and the spatial coverage of those records are not adequate. Northern Xinjiang of China is one of such areas where the records are not adequate. Here, we present a 500-yr land-surface moisture sequence from Heiyangpo Peat(48.34°N, 87.18°E, 1353 m a.s.l) in the southern Altai Mountains within northern Xinjiang. Specifically, peat carbon isotope value of cellulose(δ^(13)C_(cellulose)) was used to estimate the warm-season moisture variations and the degree of humification was used to constrain the δ^(13)C_(cellulose)-based hydrological interpretation. The climatic attributions of the interpreted hydrological variations were based on the warm-season temperature reconstructed from Belukha ice core and the warm-season precipitation inferred from the reconstructed Atlantic Multidecadal Oscillations(AMO). The results show that humification decreased and the δ^(13)C_(celluose)-suggested moisture decreased from ~1510 to ~1775 AD, implying that a constant dryingcondition may have inhibited peat decay. Our comparison with reconstructed climatic parameters suggests that the moisture-level decline was most likely resulted from a constant decline of precipitation. The results also show that humification kept a stable level and the δ^(13)C_(celluose)-suggested moisture also decreased from ~1775 to ~2013 AD, implying that peat decay in the acrotelm primarily did not depend on the water availability or an aerobic environment. Again, our comparison with reconstructed climatic parameters suggests that the land-surface moisturelevel decline was most likely resulted from a steady warming of growing-season temperature.

关键词： Peat Carbon isotope of cellulose Humification Warm-season moisture Southern Altai Mountains

Proprotein convertase 1 mRNA and protein expression in ischemic rat cortex after reperfusion

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Neural Regeneration Research 2011年第4期6卷 295-299页

作者： Shuqin Zhan An Zhou Jingquan lan Tao Yang Department of Neurology Second Affiliated Hospital Medical School of Xi'an Jiaotong University Xi'an 710004 Shaanxi Province China Robert S. Dow Neurobiology Laboratories Legacy Clinic Research and Technology Center Portland 97232 OR USA

Proprotein convertase 1 （PC1） is a member of the family of proprotein convertases （PCs）, which are the processing enzymes of neuropeptides. Previous studies have addressed PC1 effects with regard to the neuroendocrine system. In this study, the developing changes of PC1 mRNA and PC1 protein in rat cortices after transient focal cerebral ischemia were investigated by fluorescent double labeling （both in situ hybridization and immunocytochemistry） using a transient focal cerebral ischemia model in rats. The results were compared with those of sham-operated rat cortices. Both the mRNA and protein levels of PC1 in ischemic cortices decreased gradually at 4, 8, and 16 hours of reperfusion after 100 minutes of middle cerebral artery occlusion. After 24 hours of reperfusion, enhanced intensities of signals for PC1 protein were observed, while signals for PC1 mRNA remained low. These results suggest that transient focal cerebral ischemia influences PC1 mRNA and protein expression in cortices of ischemic rats. Thus, PC1 is regulated by ischemic stress.

关键词： cerebral ischemia proprotein convertase 1 cortex rats

A Distributed Decision Mechanism for Controller Load Balancing Based on Switch Migration in SDN

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China Communications 2018年第10期15卷 129-142页

作者： Tao Hu Peng Yi Jianhui Zhang Julong lan National Digital Switching System Engineering & Technological R&D Center Zhengzhou 450002 China

Software Defined Networking(SDN) provides flexible network management by decoupling control plane from data plane. And multiple controllers are deployed to improve the scalability and reliability of the control plane, which could divide the network into several subdomains with separate controllers. However, such deployment introduces a new problem of controller load imbalance due to the dynamic traffic and the static configuration between switches and controllers. To address this issue, this paper proposes a Distribution Decision Mechanism(DDM) based on switch migration in the multiple subdomains SDN network. Firstly, through collecting network information, it constructs distributed migration decision fields based on the controller load condition. Then we choose the migrating switches according to the selection probability, and the target controllers are determined by integrating three network costs, including data collection, switch migration and controller state synchronization. Finally, we set the migrating countdown to achieve the ordered switch migration. Through verifying several evaluation indexes, results show that the proposed mechanism can achieve controller load balancing with better performance.

关键词： software defined networking controller load balancing switch migration distributed decision

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地中海贫血产前诊断在出缺陷防控中的作用

医师在线 2024年第2期14卷 28-30页

作者：张兰兰黄芬芳黄艳华龚菲菲胡雪梅梁佩钦州市妇幼保健院医学遗传与产前诊断科广西钦州535000

目的探讨地中海贫血产前诊断在出生缺陷防控中的作用。方法对在孕早期(11~14周)超声引导下经腹绒毛穿刺取材247例,在孕中期(16~26周)超声引导下羊膜腔穿刺取材903例,在孕中、晚期(23~37周)超声引导下脐静脉穿刺取材73例,总共1223例单胎... 详细信息

目的探讨地中海贫血产前诊断在出生缺陷防控中的作用。方法对在孕早期(11~14周)超声引导下经腹绒毛穿刺取材247例,在孕中期(16~26周)超声引导下羊膜腔穿刺取材903例,在孕中、晚期(23~37周)超声引导下脐静脉穿刺取材73例,总共1223例单胎妊娠且有生育重型或中间型地贫患儿高风险的孕妇进行地中海贫血产前诊断。结果经腹行绒毛穿刺247例,一次穿刺成功率99.59%,2例穿刺术后2周内流产,诊断胎儿中间型、重型地贫共62例,其中重型地贫32例,通过咨询后49例胎儿中间型、重型地贫选择引产。羊水穿刺取材903例,一次穿刺成功率99.89%,有3例病例在术后2周内流产,诊断胎儿中间型、重型地贫共202例,其中重型地贫68例,通过咨询后112例胎儿中间型、重型地贫选择引产。脐血穿刺取材73例,一次穿刺成功率98.63%,术后2周内流产0例,诊断胎儿中间型、重型地贫共20例,其中重型地贫7例,通过咨询后1例重型地贫未引产,9例胎儿中间型、重型地贫选择引产。结论侵入性产前诊断技术能安全有效地应用到地中海贫血产前诊断中,有效防止中间型和重型地中海贫血患儿出生,达到优生优育的目的。

关键词：地中海贫血产前诊断出生缺陷防控

Neuroprotection in glaucoma： present and future

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Chinese Medical Journal 2013年第8期126卷 1567-1577页

作者： CHEN Shi-da WANG Lu ZHANG Xiu-lan Zhongshan Ophthalmic Center State Key Laboratory ofOphthalmology Sun Yat-sen University Guangzhou Guangdong5/oo6o China

Objective To review the updated research on neuroprotection in glaucoma, and summarize the potential agents investigated so far. Data sources The data in this review were collected from PubMed and Google Scholar databases published in English up to September 2012, with keywords including glaucoma, neuroprotection, and retinal ganglion cells, both alone and in combination. Publications from the past ten years were selected, but important older articles were not excluded. Study selection Articles about neuroprotection in glaucoma were selected and reviewed, and those that are cited in articles identified by this search strategy and judged relevant to this review were also included. Results Although lowering the intraocular pressure is the only therapy approved as being effective in the treatment of glaucoma, increasing numbers of studies have discovered various mechanisms of retinal ganglion cells death in the glaucoma and relevant neuroprotective strategies. These strategies target neurotrophic factor deprivation, excitotoxic damage, oxidative stress, mitochondrial dysfunction, inflammation, activation of intrinsic and extrinsic apoptotic signals, ischemia, and protein misfolding. Exploring the mechanism of axonal transport failure, synaptic dysfunction, the glial system in glaucoma, and stem cell used in glaucoma constitute promising research areas of the future. Conclusions Neuroprotective strategies continue to be refined, and future deep investment in researching the pathogenesis of glaucoma may provide novel and practical neuroprotection tactics. Establishing a system to assess the effects of neuroprotection treatments may further facilitate this research.

关键词： glaucoma, neuroprotection retinal ganglion cells

Effects of graphite on the microstructure and properties of ultrafine WC-11Co composites by spark plasma sintering

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Rare Metals 2011年第1期30卷 63-67页

作者： SUN lan YANG Tian＇en JIA Chengchang XIONG Ji School of Manufacturing Science and Engineering Sichuan University Chengdu 610065 China School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China

Ultrafine WC-11Co hard metals added with different proportions of graphite were prepared by spark plasma sintering at 40 MPa/1200°C for 5 min,and the influence of graphite as free carbon on the microstructure and mechanical properties were *** XRD analysis showed that decarbonization could be prevented by adding *** hard metals composed of finer and more homogeneous WC grains with little flaws can be achieved after 0 wt.% to 1.5 wt.% graphite was *** hardness and fracture toughness increase initially with increasing graphite content,and with over 1.5 wt.% they descend due to coarse grains and more ***,1.5 wt.% graphite is the optimal addition content in view of the hardness and transverse rupture ***,the coercive force decreases while the saturated magnetic intensity increases with the increase of graphite content.

关键词： composite materials tungsten carbide cobalt graphite spark plasma sintering microstructure mechanical properties

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重组人促卵泡激素药物非临床评价的思考

中国临床药理学杂志 2024年第9期40卷 1385-1392页

作者：陈美灵许曾平崔岚曹萍吴爽张晓东国家药品监督管理局药品审评中心北京100022

本文综述了重组人促卵泡激素(rFSH)药物的国内外研究进展情况,根据国内外相关指导原则及相关审评案例从审评角度梳理了rFSH药物非临床评价一般要求和常见问题,并对近年来的研发热点长效rFSH产品的临床开发前景进行分析并给出了相应的建... 详细信息

本文综述了重组人促卵泡激素(rFSH)药物的国内外研究进展情况,根据国内外相关指导原则及相关审评案例从审评角度梳理了rFSH药物非临床评价一般要求和常见问题,并对近年来的研发热点长效rFSH产品的临床开发前景进行分析并给出了相应的建议,以期为相关工作提供参考。

关键词：重组人促卵泡激素非临床评价药物研发临床开发前景

长江口北岸南通地区酸雨污染及组分变化趋势分析

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四川环境 2021年第3期40卷 55-59页

作者：徐爱兰石雯耿建生张琪王平江苏省南通环境监测中心江苏南通226006 南通大学信息科学技术学院江苏南通226019

分析2007~2019年南通市各子站降水监测点位数据得出,近10年来,全市酸雨污染大幅减轻,酸雨发生率渐趋下降,强中度酸雨逐渐消除,降水酸度和酸雨酸度均有减弱,现阶段酸雨污染以弱酸性酸雨污染为主。近年来全市硫酸根离子当量浓度呈现逐年... 详细信息

分析2007~2019年南通市各子站降水监测点位数据得出,近10年来,全市酸雨污染大幅减轻,酸雨发生率渐趋下降,强中度酸雨逐渐消除,降水酸度和酸雨酸度均有减弱,现阶段酸雨污染以弱酸性酸雨污染为主。近年来全市硫酸根离子当量浓度呈现逐年明显降低的趋势,机动车尾气排放的大量致酸物质使降雨中NO^(-)_(3)占比明显上升,SO^(2-)_(4)与NO^(-)_(3)浓度的比值已降至1.25∶1,南通市酸雨已由硫酸型向硫酸与硝酸并重混合型过渡。全市酸雨区域分布格局总体变化不大,主要呈现东南沿江沿海略高于西北部区域。

关键词：长江口北岸南通地区酸雨组分分析

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滑坡面瑞雷波波场模拟及H/V谱比探测

吉林大学学报（地球科学版） 2024年第3期54卷 1031-1041页

作者：王芃邵广周恒翔天蓝笛瑄王国顺霍科宇长安大学地质工程与测绘学院西安710054

滑坡是一种分布广泛、数量众多、危害巨大的地质灾害,准确确定滑坡滑动面对滑坡防治具有重大意义。传统的勘探手段,如钻探和地球物理方法在起伏较大的滑坡地形中具有诸多限制。本文以四川省屏山县东池庄滑坡为参考,建立了起伏地形软弱... 详细信息

滑坡是一种分布广泛、数量众多、危害巨大的地质灾害,准确确定滑坡滑动面对滑坡防治具有重大意义。传统的勘探手段,如钻探和地球物理方法在起伏较大的滑坡地形中具有诸多限制。本文以四川省屏山县东池庄滑坡为参考,建立了起伏地形软弱性土质滑坡模型,进行了瑞雷波波场模拟并经过模式分离后计算求得水平/垂直(H/V)谱比曲线。对比分析了波场传播及H/V谱比曲线的特征,发现在110道检波器排列中,中心部位检波器的峰值频率可作为计算土石分界面的卓越频率。设计了土层厚度分别为25、31、35 m的滑坡模型,发现土层厚度与峰值频率呈负相关关系。给出了地层为黏性土与泥岩时的频率-深度经验公式,得到了连续滑动面信息,经验公式计算结果与实际模型吻合较好。

关键词：软弱性滑坡 H/V谱比曲线波场模拟峰值频率