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| 1 | 长江三角洲地区大气O3和PM10的区域污染特征模拟显示文摘以TRACE-P污染源资料及上海市地方排放清单为基础,采用Models-3/CMAQ环境空气质量模型和中尺度气象模式MM5,模拟研究了2001-01和2001-07长三角近地面二次污染物O3及PM10的浓度分布及输送状况,并以上海市国控点2001年冬、夏季各10 d的小时监测数据对模型进行了验证.验证结果显示,Models-3/CMAQ对O3和PM10的模拟结果与监测值的相关系数分别为0.77和0.52;一致性指数分别达到0.81和0.99.模型对O3小时最高浓度的估算偏低27%,标准偏差为-3.1%;对PM10小时平均浓度的估算偏低10%,标准偏差为46%.模型已具备再现和模拟长三角大气污染输送过程的能力,且误差落在可接受的范围之内.模拟结果显示,2001-07长三角区域16个主要城市中,有14个城市O3小时最大浓度超过国家二级标准,高浓度O3可覆盖苏南和浙北广大区域.2001-01泰州、扬州、南京、镇江、常州等城市受本地排放源和北部大气污染输送的影响显著,大气PM10日均浓度超过PM10国家二级标准.长三角地区环境空气质量与污染类型受大气污染传输与化学转化的影响十分明显.夏季太阳辐射较强时,南部城市排放的污染物常以二次污染物的形式影响下风向城市;太阳辐射较弱的情况下,则以一次污染物输送为主的形式影响周边地区.冬季长三角区域颗粒物污染总体水平较高,这与我国北方地区排放的颗粒物在西北风作用下向长三角输送造成的影响密切相关.长三角地区的大气污染已逐渐从局地转为区域问题. | 李莉 陈长虹 黄成 黄海英 李作攀 Joshua S. Fu Carey J. Jang David G. Streets | 2008 | 环境科学2008，29，1： | 91 |
| 2 | 自发性脑出血管理指南 美国心脏协会/美国卒中协会针对医疗专业人员的指南显示文摘目的本指南旨在为自发性脑出血的诊断和治疗提供最新的全面推荐意见。方法利用PubMed进行规范化文献检索,检索时间至2013年8月底。撰写委员会成员通过远程电信会议讨论指南内容及推荐意见,采用美国心脏协会/美国卒中协会的疗效确定性水平和证据分级方案对推荐意见进行分级。由6位同行评议专家以及卒中委员会科学声明监督委员会和卒中委员会领导委员会成员对指南草案进行发表前审阅。结果本文为急性脑出血患者的医疗诊治提供了循证指南,重点包括诊断、凝血功能障碍和血压管理、继发性脑损伤防治、颅内压控制、外科治疗的作用、转归预测、康复、二级预防以及将来需要考虑的问题。本指南已纳入最新的3期临床试验结果。结论脑出血是一种需要进行早期积极救治的危重疾病。本指南为脑出血患者的目标导向治疗提供了一个框架。 | J. Claude Hemphill Ⅲ Steven M. Greenberg Craig S. Anderson Kyra Beckelr Bernard R. Bendok Mary Cushman Gordon L. Fung Joshua N. Goldstein R. LochMacdonald Pamela H Mitchell, Phillip A Scott,Magdy H Selim, Daniel Woo 高圆圆 徐欣 | 2015 | 国际脑血管病杂志2015，23，10： | 444 |
| 3 | Nano-Graphene Oxide for Cellular Imaging and Drug Delivery显示文摘Two-dimensional graphene offers interesting electronic,thermal,and mechanical properties that are currently being explored for advanced electronics,membranes,and composites.Here we synthesize and explore the biological applications of nano-graphene oxide(NGO),i.e.,single-layer graphene oxide sheets down to a few nanometers in lateral width.We develop functionalization chemistry in order to impart solubility and compatibility of NGO in biological environments.We obtain size separated pegylated NGO sheets that are soluble in buffers and serum without agglomeration.The NGO sheets are found to be photoluminescent in the visible and infrared regions.The intrinsic photoluminescence(PL)of NGO is used for live cell imaging in the near-infrared(NIR)with little background.We found that simple physisorption viaπ-stacking can be used for loading doxorubicin,a widely used cancer drug onto NGO functionalized with antibody for selective killing of cancer cells in vitro.Owing to its small size,intrinsic optical properties,large specifi c surface area,low cost,and useful non-covalent interactions with aromatic drug molecules,NGO is a promising new material for biological and medical applications. | Xiaoming Sun Zhuang Liu Kevin Welsher Joshua Tucker Robinson Andrew Goodwin Sasa Zaric Hongjie Dai | 2008 | Nano Research2008，1，3： | 118 |
| 4 | 采用PCR-DGGE技术分析蛋鸡肠道细菌种群结构及多样性显示文摘利用基于16S rDNA的PCR-DGGE(变性梯度凝胶电泳)图谱技术结合特异性和共性条带割胶回收DNA进行克隆和测序,对2、4、6和8周龄蛋鸡嗉囊、十二指肠、空肠、回肠和盲肠内容物细菌群落的结构和多样性进行了比较,并鉴定了8周龄蛋鸡部分特异性和共性群落成员,分析蛋鸡年龄和肠段部位对微生物群落结构和多样性的影响。肠道菌群DGGE图谱显示肠道部位对细菌种群结构影响很大,盲肠内微生物的多样性最高,其次是回肠和空肠,嗉囊和十二指肠的微生物多样性比较低。十二指肠内细菌与其它肠段相比差异最大,其次是盲肠与其它肠段细菌组成的差异。随着蛋鸡周龄的增加,消化道微生物经历了由简单(2周)到复杂(4周),再回复简单(6周)到复杂(8周)的变化过程。DGGE图谱中共性条带序列分析表明8周龄蛋鸡消化道前段的优势细菌是三得利乳杆菌(Lactobacillus suntoryeus)、索氏梭菌(Clostridium sordellii)和大肠杆菌,盲肠中的特异性条带主要是各种不可培养的细菌以及超巨巨单胞菌(Megamonas hypermegale)和梭菌属细菌(Clostridiumspp)。该研究结果表明蛋鸡肠道部位决定细菌群落的结构和多样性,蛋鸡的周龄影响肠道细菌多样性。 | 倪学勤 Joshua Gong Hai Yu 曾东 Shayan Sharif 周小秋 | 2008 | 畜牧兽医学报2008，39，7： | 56 |
| 5 | Implications of butyrate and its derivatives for gut health and animal production显示文摘Butyrate is produced by microbial fermentation in the large intestine of humans and animals.It serves as not only a primary nutrient that provides energy to colonocytes, but also a cellular mediator regulating multiple functions of gut cells and beyond, including gene expression, cell differentiation, gut tissue development, immune modulation, oxidative stress reduction, and diarrhea control.Although there are a large number of studies in human medicine using butyrate to treat intestinal disease, the importance of butyrate in maintaining gut health has also attracted significant research attention to its application for animal production, particularly as an alternative to in-feed antibiotics.Due to the difficulties of using butyrate in practice(i.e., offensive odor and absorption in the upper gut), different forms of butyrate,such as sodium butyrate and butyrate glycerides, have been developed and examined for their effects on gut health and growth performance across different species.Butyrate and its derivatives generally demonstrate positive effects on animal production, including enhancement of gut development, control of enteric pathogens, reduction of inflammation, improvement of growth performance(including carcass composition), and modulation of gut microbiota.These benefits are more evident in young animals, and variations in the results have been reported.The present article has critically reviewed recent findings in animal research on butyrate and its derivatives in regard to their effects and mechanisms behind and discussed the implications of these findings for improving animal gut health and production.In addition, significant findings of medical research in humans that are relevant to animal production have been cited. | ANDrea Bedford Joshua Gong | 2018 | Animal Nutrition2018，，2： | 31 |
| 6 | Seven Things We Think We Know about Auxin Transport显示文摘植物激素植物生长素的极的运输和最大值调整的局部性的植物生长素的建立胚胎的开发,干细胞维护,根和射击建筑学,和回归线生长回答。过去的十年被戏剧的进步在阐明的努力标记植物生长素运输由调整的复杂机制种生长。作为植物生长素的理解,运输规定逐渐地被详细描述,这个过程在某些方面涉及几乎所有植物生长和环境回答,变得清楚。然而,我们仍然关于这基本规章的机制的一些基本方面缺乏信息。在这评论,我们在场我们知道什么(或我们认为什么我们知道) 并且我们什么不知道大约七个调整植物生长素的过程。我们在主要、侧面的根,向光性,分叉的射击,叶扩大,和脉络在 gravitropism 讨论植物生长素运输的角色。我们也在根尖端,植物生长素运输过程的 flavonoid 调整,和植物生长素 transporters 的 translational 以后规定的突出的方面讨论植物生长素倒流 / 喷泉模型。这讨论没打算彻底,但是加亮在哪个通常认为假设要求更真实的确认的区域。 | Wendy Ann Peer Joshua J. Blakeslee Haibing Yang Angus S. Murphy | 2011 | Molecular Plant2011，4，3： | 29 |
| 7 | 金蝉花多糖的抗氧化活性及结构分析显示文摘本实验研究金蝉花多糖的抗氧化活性,并对其纯化组分进行结构分析。采用热水浸提、不同浓度乙醇分级沉淀的方法从金蝉花中提取多糖,分别获得_(50)%醇沉金蝉花多糖(_(50)%polysaccharides from Cordyceps cicadas,CP_(50))和_(80)%醇沉金蝉花多糖(CP_(80)),并检测两者的体外抗氧化活性。结果表明:CP_(50)较CP_(80)表现出较强的清除自由基的能力,且具有一定的还原能力和总抗氧化能力。CP_(50)进一步经二乙氨乙基(diethylaminoethyl,DEAE)纤维素-52和Sephadex G-100凝胶柱分离纯化,得到活性多糖CPA-1和CPB-1。经紫外扫描光谱法和高效凝胶过滤色谱法鉴定CPA-1和CPB-1为均一多糖;单糖组成分析显示两个组分中均含有葡萄糖、甘露糖和半乳糖,其物质的量比分别为:1∶0.48∶0.52和1∶0.14∶0.114。红外光谱(infrared spectroscopy,IR)及刚果红实验发现,CPA-1和CPB-1具有典型的多糖红外吸收,且含有三股螺旋分子结构。 | 封燕 贡小辉 韦德群 刘英坤 赵明 于小凤 OPEYEMI Joshua Olatunji 焦心怡 欧阳臻 | 2016 | 食品科学2016，37，13： | 30 |
| 8 | high-entropy silicide:(Mo_(0.2)Nb_(0.2)Ta_(0.2)Ti_(0.2)W_(0.2))Si_(2)显示文摘A high-entropy metal disilicide,(Mo_(0.2)Nb_(0.2)Ta_(0.2)Ti_(0.2)W_(0.2))Si_(2),has been successfully synthesized.X-ray diffraction(XRD),energy dispersive X-ray spectroscopy(EDX),and electron backscatter diffraction(EBSD)collectively show the formation of a single high-entropy silicide phase.This high-entropy(Mo_(0.2)Nb_(0.2)Ta_(0.2)Ti_(0.2)W_(0.2))Si_(2) possesses a hexagonal C40 crystal structure with ABC stacking sequence and a space group of P6222.This discovery expands the known families of high-entropy materials from metals,oxides,borides,carbides,and nitrides to a silicide,for the first time to our knowledge,as well as demonstrating that a new,non-cubic,crystal structure(with lower symmetry)can be made into highentropy phase.This(Mo_(0.2)Nb_(0.2)Ta_(0.2)Ti_(0.2)W_(0.2))Si_(2) exhibits high nanohardness of 16.7±1.9 GPa and Vickers hardness of 11.6±0.5 GPa.Moreover,it has a low thermal conductivity of 6.9±1.1Wm^(-1) K^(-1),which is approximately one order of magnitude lower than that of the widely-used tetragonal MoSi_(2) and ~1/3 of those reported values for the hexagonal NbSi_(2) and TaSi_(2) with the same crystal structure. | Joshua Gild Jeffrey Braun Kevin Kaufmann Eduardo Marin Tyler Harrington Patrick Hopkins Kenneth Vecchio Jian Luo | 2019 | Journal of Materiomics2019，5，3： | 27 |
| 9 | 动脉瘤性蛛网膜下腔出血处理指南 美国心脏协会卒中委员会特别写作组给医疗专业人员的声明显示文摘蛛网膜下腔出血(subarachnoid hemorrhage,SAH)是一种常见病,常常导致严重后果,约占全部卒中病例的5%,在美国每年有多达3万人罹患该病。美国心脏协会(American Heart Association,AHA)曾发表过“动脉瘤性SAH处理指南”。此后,在血管内技术、诊断方法以及手术和围手术期管理方面已取得了显著进展。尽管如此,SAH患者的预后依然较差,基于人群研究报告的病死率高达45%,并且存活者会遗留严重残疾。一些多中心前瞻性随机试验和前瞻性队列分析已对SAH的治疗方案产生影响。然而, | Joshua B. Bederson E. Sander Connolly H. Hunt Batjer Ralph G. Dacey Jacques E. Dion Michael N. Diringer John E. Duldner Robert E. Harbaugh Aman B. Patel Robert H. Rosenwasser 高翔(译) 李洛(译) 李海峰(译) | 2009 | 国际脑血管病杂志2009，17，4： | 24 |
| 10 | Essential oils as alternatives to antibiotics in swine production显示文摘This review article summarizes the efficacy, feasibility and potential mechanisms of the application of essential oils as antibiotic alternatives in swine production.Although there are numerous studies demonstrating that essential oils have several properties, such as antimicrobial, antioxidative and antiinflammatory effects, feed palatability enhancement and improvement in gut growth and health, there is still a need of further investigations to elucidate the mechanisms underlying their functions.In the past,the results has been inconsistent in both laboratory and field studies because of the varied product compositions, dosages, purities and growing stages and conditions of animals.The minimal inhibitory concentration(MIC) of essential oils needed for killing enteric pathogens may not ensure the optimal feed intake and the essential oils inclusion cost may be too high in swine production.With the lipophilic and volatile nature of essential oils, there is a challenge in effective delivery of essential oils within pig gut and this challenge can partially be resolved by microencapsulation and nanotechnology.The effects of essential oils on inflammation, oxidative stress, microbiome, gut chemosensing and bacterial quorum sensing(QS) have led to better production performance of animals fed essential oils in a number of studies.It has been demonstrated that essential oils have good potential as antibiotic alternatives in feeds for swine production.The combination of different essential oils and other compounds(synergistic effect) such as organic acids seems to be a promising approach to improve the efficacy and safety of essential oils in applications.High-throughput systems technologies have been developed recently,which will allow us to dissect the mechanisms underlying the functions of essential oils and facilitate the use of essential oils in swine production. | Faith A.Omonijo Liju Ni Joshua Gong Qi Wang Ludovic Lahaye Chengbo Yang | 2018 | Animal Nutrition2018，，2： | 24 |
| 11 | 夏季长三角地区臭氧非线性响应曲面模型的建立及应用显示文摘2013年8月上旬,长三角地区发生了一次大范围高浓度臭氧污染事件.本研究基于WRF-CMAQ空气质量模型系统,结合长三角地区大气污染物排放清单,构建了臭氧与其前体物之间的非线性响应曲面模型(Response surface modeling,RSM).基于RSM探讨了长三角地区O_3化学的敏感性特征,分析了上海市O_3的来源并预测不同情景下O_3的变化,提出O_3污染的最优控制方案.研究结果表明,长三角地区夏季O3主控因素区域差别较大,上海环科院、杭州卧龙桥、南京玄武湖等城区点位属于VOC控制型;徐州铜山、合肥肥西、丽水青田等郊区属于NOx控制型.O_3的敏感性特征在不同浓度水平下也呈现较大差异,随着O_3浓度水平的升高,各地区NOx敏感性均有所增加.从区域来源来看,远距离传输对平日上海O_3贡献较大,占50%以上;而在O_3污染日,本地及区域贡献为72.1%,而远距离传输贡献下降至27.9%.快速预测了110组减排情景,表明在本地及区域前体物均减排70%的情况下,2013年8月上海O_3浓度能完全达标. | 严茹莎 李莉 安静宇 卢清 黄成 王书肖 朱云 Carey J.Jang Joshua S.Fu | 2016 | 环境科学学报2016，36，4： | 22 |
| 12 | 基于响应面模型的区域大气污染控制辅助决策工具研发显示文摘基于CMAQ模型结果,利用高维克里金插值算法,建立了排放控制因子与污染物环境浓度的响应面模型(RSM),实现了大气污染可控源排放与复合污染水平的实时函数响应.研究结果显示,RSM对PM2.5的预测结果与CMAQ实际模拟结果的误差在容许范围内(最大误差小于0.20μg.m-3,3.89%).基于所建立的RSM,开发了RSM-VAT区域大气污染控制可视化辅助决策工具.使用RSM-VAT对美国8个典型城市的PM2.5污染状况进行了控制情景分析,通过'可视化展示'和'图表分析'二大模块,输出不同控制情景下的环境污染物浓度的实时响应图、可视化展示和数据分析图表等结果. | 劳苑雯 朱云 Carey Jang Che Jen Lin 邢佳 陈志润 谢俊平 王书肖 Joshua Fu | 2012 | 环境科学学报2012，32，8： | 20 |
| 13 | 振动信号短时分析方法及在机械故障诊断中的应用显示文摘研究了低信噪比情况下提取周期性冲击故障信号特征的短时分析方法。定量分析了短时能量方法的抑噪特性 ,指出信号的局部特征越明显则短时能量处理越能显著地提高信噪比 ,短时能量函数中实际有用信号能量与实际噪声信号能量的比值可作为一特征量使用。建立了信号一步自相关系数与重心频率及过零率之间的定量关系 ,指出短时一步自相关系数和短时过零率的物理含义相同 ,反映的只是信号功率谱重心的变化 ,与信号能量的变化无关 ,故不适宜于分析受强噪声干扰的时变故障信号。 | 朱利民 钟秉林 贾民平 Joshua Altmann | 2000 | 振动工程学报2000，13，3： | 20 |
| 14 | High Performance In Vivo Near-IR (>1 μm) Imaging and Photothermal Cancer Therapy with Carbon Nanotubes显示文摘Short single-walled carbon nanotubes(SWNTs)functionalized by PEGylated phospholipids are biologically non-toxic and long-circulating nanomaterials with intrinsic near infrared photoluminescence(NIR PL),characteristic Raman spectra,and strong optical absorbance in the near infrared(NIR).This work demonstrates the first dual application of intravenously injected SWNTs as photoluminescent agents for in vivo tumor imaging in the 1.0-1.4μm emission region and as NIR absorbers and heaters at 808 nm for photothermal tumor elimination at the lowest injected dose(70μg of SWNT/mouse,equivalent to 3.6 mg/kg)and laser irradiation power(0.6 W/cm2)reported to date.Ex vivo resonance Raman imaging revealed the SWNT distribution within tumors at a high spatial resolution.Complete tumor elimination was achieved for large numbers of photothermally treated mice without any toxic side effects after more than six months post-treatment.Further,side-by-side experiments were carried out to compare the performance of SWNTs and gold nanorods(AuNRs)at an injected dose of 700μg of AuNR/mouse(equivalent to 35 mg/kg)in NIR photothermal ablation of tumors in vivo.Highly effective tumor elimination with SWNTs was achieved at 10 times lower injected doses and lower irradiation powers than for AuNRs.These results suggest there are significant benefits of utilizing the intrinsic properties of biocompatible SWNTs for combined cancer imaging and therapy. | Joshua T.Robinson Kevin Welsher Scott M.Tabakman Sarah P.Sherlock Hailiang Wang Richard Luong Hongjie Dai | 2010 | Nano Research2010，3，11： | 20 |
| 15 | WJBC 5^(th) Anniversary Special Issues(2): Proteomics In 2014, can we do better than CA125 in the early detection of ovarian cancer?显示文摘Ovarian cancer is a lethal gynecologic malignancy with greater than 70% of women presenting with advanced stage disease. Despite new treatments, long term outcomes have not significantly changed in the past 30 years with the five-year overall survival remaining between 20% and 40% for stage Ⅲ and Ⅳ disease. In contrast patients with stage Ⅰ disease have a greater than 90% five-year overall survival. Detection of ovarian cancer at an early stage would likely have significant impact on mortality rate. Screening biomarkers discovered at the bench have not translated to success in clinical trials. Existing screening modalities have not demonstrated survival benefit in completed prospective trials. Advances in high throughput screening are making it possible to evaluate the development of ovarian cancer in ways never before imagined. Data in the form of human '-omes' including the proteome, genome, metabolome, and transcriptome are now available in various packaged forms. With the correct pooling of resources including prospective collection of patient specimens, integration of high throughput screening, and use of molecular heterogeneity in biomarker discovery, we are poised to make progress in ovarian cancer screening. This review will summarize current biomarkers, imaging, and multimodality screening strategies in the context of emerging technologies. | Joshua G Cohen Matthew White Ana Cruz Robin Farias-Eisner | 2014 | World Journal of Biological Chemistry2014，5，3： | 18 |
| 16 | Amelioration of experimental colitis by Astragalus membranaceus through anti-oxidation and inhibition of adhesion molecule synthesis显示文摘AIM: To investigate the protective effects of Astragalus membranaceus(Am) against hapten-induced colitis in male Sprague-Dawley rats as well as its underlying mechanism.METHODS: Experimental colitis was induced in rats by enema administration of 2,4-dinitrobenzene sulfonic acid (DNBS). Rats were either pretreated with Am extract (2 or 4 g/kg, p.o. once daily) starting from 10 d before DNBS enema, or received Am post-treatment (2 or 4 g/kg, p.o.twice daily) on the three consecutive days following DNBS administration. Colonic lesion area and histological damage were determined, while the activities of myeloperoxidase (MPO) and xanthine oxidase, as well as reduced glutathione (GSH) content were measured in the excised colonic tissues. Besides, protein expression of inducible nitrite oxide synthase (iNOS), intercellular adhesion molecule-1 (ICAM-1) and P-selectin was also detected by Western blot analysis.RESULTS: Our findings had shown that both macroscopic lesion area and histological colonic damage induced by DNBS were significantly reduced by both Am pre- and post-treatments. These were accompanied by attenuation of the elevated colonic MPO activity and downregulation of the iNOS, P-selectin, and ICAM-1 protein expression.Besides, deprivation of colonic GSH level under colitis condition was also preserved.CONCLUSION: These results demonstrate that Am possesses both preventive and therapeutic potential in experimental colitis. The anti-inflammatory actions involve anti-oxidation along with inhibition of adhesion molecule synthesis in the colonic tissues. | Joshua Ka-Shun Ko Flora Ying-Lee Lam Andrew Pok-Lap Cheung | 2005 | World Journal of Gastroenterology2005，11，37： | 17 |
| 17 | Molecular approaches to study the insect gut symbiotic microbiota at the 'omics' age显示文摘 | Weibing Shi Ryan Syrenne Jian-Zhong Sun Joshua S. Yuan | 2010 | Insect Science2010，17，3： | 17 |
| 18 | An XA21-Associated Kinase (OsSERK2) Regulates Immunity Mediated by the XA21 and XA3 Immune Receptors显示文摘米饭 XA21 有免疫力的受体 kinase 和在结构上联系了 XA3 受体授与免疫到 Xanthomonas oryzae pv。oryzae (Xoo ) ,细菌的叶老家的原因的代理人。这里,我们报导 OsSERK2 的隔离(米饭体的 embryogenesis receptorkinase 2 ) 并且证明 OsSERK2 断然调整免疫由 XA21 和 XA3 以及米饭免疫者 receptorFLS2 (OsFLS2 ) 调停了。为 OsSerk2 显示的瑞斯植物 silenced 改变了形态学并且把敏感归结为荷尔蒙 brassinolide。OsSERK2 在酵母与每有免疫力的受体的 intracellulardomains 交往以一种 kinase 活动依赖者方式的二混血儿的系统。OsSERK2 在 vitro 与 XA21 经历 bidirectionaltransphosphorylation 并且在 vivo 与 XA21 形成组成的建筑群。这些结果在三米饭免疫者受体的功能为 OsSERK2 表明一个必要角色并且建议和米饭免疫者受体的 thatdirect 相互作用为他们的功能是批评的。一起拿,我们的调查结果建议米饭 XA21, XA3,和 FLS2 的反省 OsSERK2 的规定的 thatthe 机制不同于 AtSERK3/BAK1-mediated regulationof Arabidopsis FLS2 和 EFR.Key 词的: | Xuewei Chena Shimin Zuo Benjamin Schwessinger Mawsheng Chern Patrick E. Canlas Deling Ruan Xiaogang Zhou Jing Wang Arsalan Daudi Christopher J. Petzold Joshua L. Heazlewood Pamela C. Ronald | 2014 | Molecular Plant2014，7，5： | 17 |
| 19 | 铂合金氧还原催化剂:合成、结构和性能显示文摘质子交换膜燃料电池是一种将燃料中的化学能直接转化为电能的装置,它具有转化效率高、能量密度高、低温启动、易于操作等优点,因而被认为是最具发展前景的新能源利用方式,在电动汽车、便携电源及分散式电站有着广泛应用.但是,目前质子交换膜燃料电池技术的发展面临着巨大挑战,主要问题包括高成本、低功率密度和低寿命.众所周知,质子交换膜燃料电池中的阴极氧还原反应在酸性条件下是一个复杂的四电子过程,动力学速度缓慢,限制了电池的最终性能.目前大量使用的阴极氧还原催化剂是细小的铂或铂合金纳米颗粒负载在碳载体上,其成本占燃料电池总成本的比例最大.制约燃料电池商业化发展的另一个重要问题是电池寿命低,其中氧还原催化剂的稳定性是决定电池寿命的主要因素.在这样的研究背景下,如何降低催化剂中铂的用量、提高催化剂活性和稳定性显得尤为重要,这也是近年来国内外学者研究的热点.在铂基合金催化剂中,通常采用过渡金属元素作为掺杂元素,由于原子半径不匹配(几何效应)以及电子结构不同(电子效应),合金催化剂表现出优于纯铂催化剂的催化性能.近几年,对于铂基合金催化剂的研究已取得重大进展,以合金组成和结构研究为基础,通过精确控制原子结构、调控表面电子状态以及制备工艺,获得了各种特殊形貌的催化剂,大大提高了催化活性.本文深入综述了近年来铂基合金氧还原催化剂制备、形貌和性能,特别关注了催化剂形貌和催化活性之间的关系.值得注意的是,具有有序原子排列的铂合金催化剂不仅在半电池中表现出优异活性,在实际质子交换膜燃料电池中也显示了很好的活性和稳定性.另一方面,碳载体的形貌及微观结构也对提高催化活性和稳定性起到决定性作用,通过化学手段加强金属纳米颗粒与碳载体之间的相互作用也是提高催化剂稳定性的重要途径.尽管铂基氧还原催化剂在近几年取得了重要进展,但在实际商业化过程中还存在诸多挑战,本文在综述进展的基础上,对铂基催化剂的发展提出了展望.首先,对于氧还原反应机理仍需要深入研究,采用更加精确的理论模型模拟氧还原动力学过程,以获得影响催化活性的关键因素.其次,提高催化剂在膜电极中的催化活性和利用率.目前,氧还原催化剂在半电池测试中性能优异,但是实际燃料电池操作条件下其性能远不能达到要求,这与膜电极、催化剂层及扩散层结构相关.因此,基于不同铂基催化剂的特性,合理设计膜电极组件的结构是将催化剂进行实际应用的基础.最后,催化剂的稳定性仍需进一步提高,尽管目前大部分催化剂在实验室半电池研究中表现了很好的稳定性,但在实际燃料电池中的稳定性研究还不足,而且对催化剂在膜电极中性能衰退机理的研究也非常有限.因此,对于铂基氧还原催化剂的研发仍需要国内外科研工作者不懈的努力. | 王晓霞 Joshua Sokolowski 刘辉 武刚 | 2020 | Chinese Journal of Catalysis2020，41，5： | 15 |
| 20 | Biomarkers for the diagnosis of Alzheimer's disease, dementia Lewy body, frontotemporal dementia and vascular dementia显示文摘Background Dementia is a chronic brain disorder classified by four distinct diseases that impact cognition and mental degeneration. Each subgroup exhibits similar brain deficiencies and mutations. This review will focus on four dementia subgroups: Alzheimer's disease, vascular dementia, frontotemporal dementia and dementia Lewy body. Aim The aim of this systematic review is to create a concise overview of unique similarities within dementia used to locate and identify new biomarker methods in diagnosing dementia. Methods 123 300 articles published after 2010 were identified from PubMed, JSTOR, WorldCat Online Computer Library and PALNI (Private Academic Library Network of Indiana) using the following search items (in title or abstract):'Neurodegenerative Diseases' OR 'Biomarkers' OR 'Alzheimer's Disease' OR 'Frontal Temporal Lobe Dementia' OR 'Vascular Dementia, OR 'Dementia Lewy Body' OR 'Cerebral Spinal Fluid' OR 'Mental Cognitive Impairment'. 47 studies were included in the qualitative synthesis. Results Evidence suggested neuroimaging with amyloid positron emission tomography (PET) scanning and newly found PET tracers to be more effective in diagnosing Alzheimer's and amnesiac mental cognitive impairment than carbon-11 Pittsburgh compound-B radioisotope tracer. Newly created methods to make PET scans more accurate and practical in clinical settings signify a major shift in diagnosing dementia and neurodegenerative diseases. Conclusion Vast improvements in neuroimaging techniques have led to newly discovered biomarkers and diagnostics. Neuroimaging with amyloid PET scanning surpasses what had been considered the dominant method of neuroimaging and MRI. Newly created methods to make PET scans more accurate and practical in clinical settings signify a major shift in diagnosing dementia pathology. Continued research and studies must be conducted to improve current findings and streamline methods to further subcategorise neurodegenerative disorders and diagnosis. | Joshua Marvin Anthony Maclin Tao Wang Shifu Xiao | 2019 | General Psychiatry2019，32，1： | 14 |
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