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The role of titanium at the interface of hematite photoanode in multisite mechanism:Reactive site or cocatalyst site?
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作者 Minfei Xie Xing Ji +6 位作者 Huaying Meng Nanbing Jiang Zhenyu Luo Qianqian Huang Geng Sun Yunhuai Zhang Peng Xiao 《Chinese Journal of Catalysis》 SCIE CAS CSCD 2024年第9期77-86,共10页
Hematite(α-Fe_(2)O_(3))constitutes one of the most promising photoanode materials for oxygen evolution reaction(OER).Recent research on Fe_(2)O_(3) have found a fast OER rate dependence on surface hole density,sugges... Hematite(α-Fe_(2)O_(3))constitutes one of the most promising photoanode materials for oxygen evolution reaction(OER).Recent research on Fe_(2)O_(3) have found a fast OER rate dependence on surface hole density,suggesting a multisite reaction pathway.However,the effect of heteroatom in Fe_(2)O_(3) on the multisite mechanism is still poorly understood.Herein we synthesized Fe_(2)O_(3) on Ti substrates(Fe_(2)O_(3)/Ti)to study the oxygen intermediates of OER by light-dark electrochemical scans.We identified the Fe-OH species disappeared and Ti-OH intermediates appeared on Fe_(2)O_(3)/Ti when pH=11‒14,which significantly improved the OER performance of Fe_(2)O_(3)/Ti.Combined with the density functional theory calculations,we propose that Ti atom acts as cocatalyst site and captures proton from neighboring Fe-OH species under highly alkaline condition,thereby promoting the coupling of Fe=O and reducing the energy barrier of the non-electrochemical step.Our work provides a new insight into the role of heteroatom in OER multisite mechanism based on clarifying the reaction intermediates. 展开更多
关键词 HEMATITE Oxygen evolution reaction multisite mechanism INTERMEDIATE Proton capture
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MultiSite Gateway技术在疟原虫条件性基因打靶载体快速构建中的应用
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作者 王各各 李娇娜 +4 位作者 杜峰 邓舒 梁佳元 曹雅明 罗恩杰 《中国医科大学学报》 CAS CSCD 北大核心 2012年第12期1068-1072,共5页
目的构建可条件性敲除约氏疟原虫ebl基因的打靶载体。方法以约氏疟原虫基因组DNA为模板,PCR扩增EBL-3U和EBL-5U1、EBL-5U2+EBL.orf同源臂片段,利用MultiSite Gateway技术,完成若干DNA片段的定性重组,构建打靶载体pCHD-EBL-RFT,并对质粒... 目的构建可条件性敲除约氏疟原虫ebl基因的打靶载体。方法以约氏疟原虫基因组DNA为模板,PCR扩增EBL-3U和EBL-5U1、EBL-5U2+EBL.orf同源臂片段,利用MultiSite Gateway技术,完成若干DNA片段的定性重组,构建打靶载体pCHD-EBL-RFT,并对质粒酶切和测序鉴定。PCR扩增约氏疟原虫UIS4-5U片段,置换质粒PbUIS4/flp中原有同源臂,并通过位点特异突变技术,获取AvrII和NheI两种线性化位点,构建插入载体PyUIS4/flp。结果构建出打靶载体pCHD-EBL-FRT和PyUIS4/flp,酶切鉴定和测序分析正确。结论将MultiSite Gateway技术成功地用于疟原虫条件打靶载体的构建,建立了以MultiSite Gateway技术为基础的打靶载体构建体系。 展开更多
关键词 疟原虫 质粒 基因打靶 multisite GATEWAY技术
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Multisite mutations of the PRSS1 gene in a Chinese patient with chronic pancreatitis 被引量:1
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作者 Liu, Qi-Cai Gao, Feng +1 位作者 Cheng, Zu-Jian Ou, Qi-Shui 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS 2008年第3期331-332,共2页
BACKGROUND: Chronic pancreatitis shows alterations in the trypsinogen gene (protease serine 1, PRSS1) in some individuals. The conversion of trypsinogen to trypsin in the pancreas is believed to be one of the causes o... BACKGROUND: Chronic pancreatitis shows alterations in the trypsinogen gene (protease serine 1, PRSS1) in some individuals. The conversion of trypsinogen to trypsin in the pancreas is believed to be one of the causes of pancreatitis. This study was to identify the mutation of the PRSS1 gene in a Chinese patient with chronic pancreatitis and to analyze the clinical features of the disease. METHODS: In 6 patients with chronic pancreatitis and 120 normal controls, PRSS1 genes were amplified by the polymerase chain reaction and the products were analyzed by sequencing. RESULTS: Multisite mutations of PRSS1 were found in a patient with chronic pancreatitis. C to A mutation occurred in exon 3 of PRSS1, and T to A mutation in the same exon. These mutations were not found in normal controls or the patients with chronic pancreatitis. CONCLUSION: These are novel mutations in PRSS1. 展开更多
关键词 chronic pancreatitis PRSS1 multisite mutation
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Sequential reactant water management by complementary multisite catalysts for surpassing platinum hydrogen evolution activity
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作者 Yu Lin Defang Ding +5 位作者 Shicheng Zhu Qunlei Wen Huangjingwei Li Zhen Li Youwen Liu Yi Shen 《Nano Research》 SCIE EI CSCD 2024年第3期1232-1241,共10页
Alkaline hydrogen evolution reaction(HER)offers a near-zero-emission approach to advance hydrogen energy.However,the activity limited by the multiple reaction steps involving H_(2)O molecules transfer,absorption,and a... Alkaline hydrogen evolution reaction(HER)offers a near-zero-emission approach to advance hydrogen energy.However,the activity limited by the multiple reaction steps involving H_(2)O molecules transfer,absorption,and activation still unqualified the thresholds of economic viability.Herein,we proposed a multisite complementary strategy that incorporates hydrophilic Mo and electrophilic V into Ni-based catalysts to divide the distinct steps on atomically dispersive sites and thus realize sequential regulation of the HER process.The Isotopic labeled in situ Raman spectroscopy describes 4-coordinated hydrogen bonded H_(2)O to be free H_(2)O passing the inner Helmholtz plane in the vicinity of the catalysts under the action of hydrophilic Mo sites.Furthermore,potential-dependent electrochemical impedance spectroscopy(EIS)reveals that electrophilic V sites with abundant 3d empty orbitals could activate the lone-pair electrons in the free H_(2)O molecules to produce more protic hydrogen,and dimerize into H_(2) at the Ni sites.By the sequential management of reactive H_(2)O molecules,NiMoV oxides multisite catalysts surpass Pt/C hydrogen evolution activity(49 mV@10 mA∙cm^(-2) over 140 h).Profoundly,this study provides a tangible model to deepen the comprehension of the catalyst–electrolyte interface and create efficient catalysts for diverse reactions. 展开更多
关键词 hydrogen evolution activity complementary multisite catalysts sequential reactive water management interfacial water molecules
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mitoTALENs植物线粒体基因编辑载体的构建方法
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作者 周家伟 武志强 《生物技术通报》 CAS CSCD 北大核心 2024年第10期172-180,共9页
【目的】mitoTALENs植物线粒体基因编辑技术能够高效地实现线粒体基因的敲除,进而有效实现线粒体基因功能的研究,但mitoTALENs载体构建过程非常的繁琐复杂且目前仍没有较为系统完整的载体构建方法作为参考。为解决这个问题,结合前人已... 【目的】mitoTALENs植物线粒体基因编辑技术能够高效地实现线粒体基因的敲除,进而有效实现线粒体基因功能的研究,但mitoTALENs载体构建过程非常的繁琐复杂且目前仍没有较为系统完整的载体构建方法作为参考。为解决这个问题,结合前人已发表的及本实验室摸索出的方法对mitoTALENs载体构建的完整过程进行了详尽描述,为之后利用mitoTALENs技术进行植物线粒体基因功能研究的研究者们提供重要参考。【方法】以水稻线粒体WA352基因作为目的基因,利用其序列特异性区域设计了靶点TAL,首先采用Platinum gate TALEN assembly的两步组装技术分别构建了mitoTALENs的TALEN-left和TALEN-right载体,然后利用multisite LR反应将TALEN-left、TALEN-right及含有其他功能元件的进入载体和目的载体进行反应,生成最终的表达载体。【结果】第一步组装构建10个载体,第二步组装构建2个载体,最后通过multisite LR反应构建1个终表达载体。【结论】详细介绍了mitoTALENs载体的构建过程,为该技术使用者提供重要参考,以促进植物线粒体基因编辑研究领域的发展。 展开更多
关键词 线粒体基因编辑 mitoTALENs载体 Platinum gate TALEN assembly multisite LR
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Independent and reproducible hippocampal radiomic biomarkers for multisite Alzheimer’s disease:diagnosis,longitudinal progress and biological basis 被引量:15
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作者 Kun Zhao Yanhui Ding +21 位作者 Ying Han Yong Fan Aaron F.Alexander-Bloch Tong Han Dan Jin Bing Liu Jie Lu Chengyuan Song Pan Wang Dawei Wang Qing Wang Kaibin Xu Hongwei Yang Hongxiang Yao Yuanjie Zheng Chunshui Yu Bo Zhou Xinqing Zhang Yuying Zhou Tianzi Jiang Xi Zhang Yong Liu 《Science Bulletin》 SCIE EI CAS CSCD 2020年第13期1103-1113,M0004,共12页
Hippocampal morphological change is one of the main hallmarks of Alzheimer’s disease(AD).However,whether hippocampal radiomic features are robust as predictors of progression from mild cognitive impairment(MCI)to AD ... Hippocampal morphological change is one of the main hallmarks of Alzheimer’s disease(AD).However,whether hippocampal radiomic features are robust as predictors of progression from mild cognitive impairment(MCI)to AD dementia and whether these features provide any neurobiological foundation remains unclear.The primary aim of this study was to verify whether hippocampal radiomic features can serve as robust magnetic resonance imaging(MRI)markers for AD.Multivariate classifier-based support vector machine(SVM)analysis provided individual-level predictions for distinguishing AD patients(n=261)from normal controls(NCs;n=231)with an accuracy of 88.21%and intersite crossvalidation.Further analyses of a large,independent the Alzheimer’s Disease Neuroimaging Initiative(ADNI)dataset(n=1228)reinforced these findings.In MCI groups,a systemic analysis demonstrated that the identified features were significantly associated with clinical features(e.g.,apolipoprotein E(APOE)genotype,polygenic risk scores,cerebrospinal fluid(CSF)Ab,CSF Tau),and longitudinal changes in cognition ability;more importantly,the radiomic features had a consistently altered pattern with changes in the MMSE scores over 5 years of follow-up.These comprehensive results suggest that hippocampal radiomic features can serve as robust biomarkers for clinical application in AD/MCI,and further provide evidence for predicting whether an MCI subject would convert to AD based on the radiomics of the hippocampus.The results of this study are expected to have a substantial impact on the early diagnosis of AD/MCI. 展开更多
关键词 Hippocampal radiomic features multisite Alzheimer’s disease MRI Independent cross-validation Brain biomarker Biological basis
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ASAF: altered spontaneous activity fingerprinting in Alzheimer’s disease based on multisite fMRI 被引量:4
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作者 Jiachen Li Dan Jin +20 位作者 Ang Li Bing Liu Chengyuan Song Pan Wang Dawei Wang Kaibin Xu Hongwei Yang Hongxiang Yao Bo Zhou Alexandre Bejanin Gael Chetelat Tong Han Jie Lu Qing Wang Chunshui Yu Xinqing Zhang Yuying Zhou Xi Zhang Tianzi Jiang Yong Liu Ying Han 《Science Bulletin》 SCIE EI CAS CSCD 2019年第14期998-1010,共13页
Several monocentric studies have noted alterations in spontaneous brain activity in Alzheimer's disease (AD), although there is no consensus on the altered amplitude of low-frequency fluctuations in AD patients. T... Several monocentric studies have noted alterations in spontaneous brain activity in Alzheimer's disease (AD), although there is no consensus on the altered amplitude of low-frequency fluctuations in AD patients. The main aim of the present study was to identify a reliable and reproducible abnormal brain activity pattern in AD. The amplitude of local brain activity (AM), which can provide fast mapping of spontaneous brain activity across the whole brain, was evaluated based on multisite rs-fMRI data for 688 subjects (215 normal controls (NCs), 221 amnestic mild cognitive impairment (aMCI) 252 AD). Two-sample t-tests were used to detect group differences between AD patients and NCs from the same site. Differences in the AM maps were statistically analyzed via the Stouffer's meta-analysis. Consistent regions of lower spontaneous brain activity in the default mode network and increased activity in the bilateral hippocampus/parahippocampus, thalamus, caudate nucleus, orbital part of the middle frontal gyrus and left fusiform were observed in the AD patients compared with those in NCs. Significant correlations (P?<?0.05, Bonferroni corrected) between the normalized amplitude index and Mini-Mental State Examination scores were found in the identified brain regions, which indicates that the altered brain activity was associated with cognitive decline in the patients. Multivariate analysis and leave-one-site-out cross-validation led to a 78.49% prediction accuracy for single-patient classification. The altered activity patterns of the identified brain regions were largely correlated with the FDG-PET results from another independent study. These results emphasized the impaired brain activity to provide a robust and reproducible imaging signature of AD. 展开更多
关键词 Brain SPONTANEOUS activity multisite Biomarkers Leave-one-site-out cross-validation Alzheimer's disease
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Multisite co-allocation scheduling algorithms for parallel jobs in computing grid environments 被引量:4
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作者 ZHANG Weizhe FANG Binxing +3 位作者 HU Mingzeng LIU Xinran ZHANG Hongli GAO Lei 《Science in China(Series F)》 2006年第6期906-926,共21页
Cooperation of multi-domain massively parallel processor systems in computing grid environment provides new opportunities for multisite job scheduling. At the same time, in the area of co-allocation, heterogeneity, ne... Cooperation of multi-domain massively parallel processor systems in computing grid environment provides new opportunities for multisite job scheduling. At the same time, in the area of co-allocation, heterogeneity, network adaptability and scalability raise the challenge for the international design of multisite job scheduling models and algorithms. It presents multisite job scheduling schema through the introduction of multisite job scheduling model and the performance model under the grid environment. It introduces two job multisite and cooperative scheduling models and algorithms with the core of the optimal and greedy-heuristic resource selection strategies. Meanwhile, compared with single and multisite cooperative scheduling models and algorithms introduced by Sabin, Yahyapour and other persons, the validity and advance of the scheduling model and the performance model herein are proved. 展开更多
关键词 computational grid parallel job multisite co-allocation resource selection resource reservation and job backfilling.
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基于WEB服务器方式中优化ClearCase手动同步系统的实现
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作者 赵新跃 顾玉雯 《计算机应用与软件》 CSCD 北大核心 2008年第1期190-192,共3页
针对ClearCase同步功能的不足,使用网页浏览的方式,运用适合Unix、Solaris等操作系统的Perl脚本语言及ASP客户端脚本语言编写程序代码,改善繁琐的操作界面,简化手动同步的步骤,提高手动同步功能的实用价值,构建了具有Web服务器方式的运... 针对ClearCase同步功能的不足,使用网页浏览的方式,运用适合Unix、Solaris等操作系统的Perl脚本语言及ASP客户端脚本语言编写程序代码,改善繁琐的操作界面,简化手动同步的步骤,提高手动同步功能的实用价值,构建了具有Web服务器方式的运行环境,优化了手动同步功能。 展开更多
关键词 CLEARCASE multisite WEB服务器
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FY-3A/MERSI, ocean color algorithm, products and demonstrative applications 被引量:4
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作者 SUN Ling GUO Maohua +2 位作者 ZHU Jianhua HU Xiuqing SONG Qingjun 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2013年第5期75-81,共7页
A medium resolution spectral imager (MERSI) on-board the first spacecraft of the second generation of Chinas polar-orbit meteorological satellites FY-3A, is a MODIS-like sensor with 20 bands covering visible to ther... A medium resolution spectral imager (MERSI) on-board the first spacecraft of the second generation of Chinas polar-orbit meteorological satellites FY-3A, is a MODIS-like sensor with 20 bands covering visible to thermal infrared spectral region. FY-3A/MERSI is capable of making continuous global observations, and ocean color application is one of its main targets. The objective is to provide information about the ocean color products of FY-3A/MERSI, including sensor calibration, ocean color algorithms, ocean color prod- ucts validation and applications. Although there is a visible on-board calibration device, it cannot realize the on-board absolute radiometric calibration in the reflective solar bands. A multisite vicarious calibration method is developed, and used for monitoring the in-flight response change and providing post-launch cal- ibration coefficients updating. FY-3A/MERSI ocean color products consist of the water-leaving reflectance retrieved from an atmospheric correction algorithm, a chlorophyll a concentration (CHL1) and a pigment concentration (PIG1) from global empirical models, the chlorophyll a concentration (CHL2), a total sus- pended mater concentration (TSM) and the absorption coefficient of CDOM and NAP (YS443) from Chi- na's regional empirical models. The atmospheric correction algorithm based on lookup tables and ocean color components concentration estimation models are described. By comparison with in situ data, the FY-3A/MERSI ocean color products have been validated and preliminary results are presented. Some suc- cessful ocean color applications such as algae bloom monitoring and coastal suspended sediment variation have demonstrated the usefulness of FY-3A/MERSI ocean color products. 展开更多
关键词 FY-3A/MERSI ocean color multisite calibration atmospheric correction China's regional model
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A molecularly imprinted polymer receptor for the enantiomeric recognition of amino acid hydantoins mimicking cooperative hydrogen bonds between nucleotide bases 被引量:1
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作者 周杰 何锡文 郭洪声 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2000年第4期482-488,共7页
Using acrylamide as hydrogen bonding functional monomer and (5R)-5-benzylhydantoin as template, a molecularly imprinted polymer was prepared in a polar solvent, which exhibited good enantiomeric recognition properties... Using acrylamide as hydrogen bonding functional monomer and (5R)-5-benzylhydantoin as template, a molecularly imprinted polymer was prepared in a polar solvent, which exhibited good enantiomeric recognition properties. The binding characteristics and selectivity of the polymer were evaluated by batch methods. Scatchard analysis showed that two classes of binding sites were produced in the polymer matrix and their dissociation constants were calculated to be 3.5 × 10?5mol/L and 4.3 × 10?4 mol/L, respectively, by utilizing the model of multiple independent classes of binding sites. These results were more reasonable than those obtained by Scatchard analysis, which was in agreement with the prediction of the binding characteristics of the polymer by exploring the effect of acrylamide on UV spectra of (5R)-5-benzylhydantoin. The substrate and enantio-selectivity of the polymer was investigated. Finally, the study of effect of water on the chiral separation factor of the polymer further proved that the hydrogen bonding interactions played an important role in the recognition of the acrylamide-based molecularly imprinted polymers. 展开更多
关键词 (5R)-5-Benzylhydantoin molecular imprinting molecular recognition multisite binding model ENANTIOSELECTIVITY
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