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关键词： Ultra high-performance liquid   chromatography-mass spectrometry   Data mining   Metabolic fingerprinting   Metabolomics   Multivariate data analysis   TOF MASS-SPECTROMETRY   PLANT METABOLOMICS   GENOMICS   H-1-NMR   RATS  

摘要： Ultra high-performance liquid chromatography hyphenated to mass spectrometry (UHPLC-MS) technologies has been widely applied in metabolomics, and the high resolution and peak capacity thereof are only some of the key aspects that are exploited in such and related fields. In the current study, we investigated if low resolution chromatography, with the aid of multivariate data analyses, could be sufficient for a metabolic fingerprinting study that aims at discriminating between samples of different biological status or origin. UHPLC-MS data from chemically-treated Arabidopsis thaliana plants were used and chromatograms with different gradient lengths were compared. MarkerLynx (TM) technology was employed for data mining, followed by principal component analysis (PCA) and orthogonal projections to latent structure discriminant analysis (OPLS-DA) as multivariate statistical interpretations. The results showed that, despite the congestion in low resolution chromatograms (of 5 and 10 min), samples could be classified based on their respective biological background in a similar manner as when using chromatograms with better resolution (of 20 and 40 min). This paper thus underlines that, in a metabolic fingerprinting study, low resolution chromatography together with multivariate data analyses suffice for biological classification of samples. The results also suggest that, depending on the initial objective of the undertaken study, optimisation in chromatographic resolution prior to full scale metabolomics studies is mandatory.

关键词： Positive ions  

摘要： It is important to understand the electrolyte-electrode interactions for fabricating graphene oxide (GO)- and ionic liquid (IL)-based ultracapacitors. Therefore, we explored how the type and size of the cations in various ILs determine the nature of processed materials. In all cases, the ILs intercalate into the graphitic structure but marked differences are observed during exfoliation via thermal reduction. The combination of a long alkyl chain ammonium-based cation and a large-volume anion leads to strong interactions and defect formation, as evidenced by CO2 production during annealing. In contrast, using the same anions but different cations stabilize the GO functional groups below 400 degrees C.

关键词： Synchronization   Localization   Time of arrival (TOA)   Clock bias   Wireless sensor networks  

摘要： This paper considers the joint node synchronization and localization problem, a key enabling aspect for wireless sensor networks. A new algorithm that can jointly estimate the clock bias and the position of an unknown sensor node is developed. The newly proposed method only involves the applications of closed-form weighted least squares (WLS) technique and therefore has lower computational complexity than conventional maximum likelihood (ML) estimators. More importantly, through theoretical performance analysis, the new algorithm is shown to be able to achieve the Cramer-Rao Lower Bound (CRLB) accuracy under the condition of high signal-to-noise ratio (SNR), a prominent advantage over other existing closed-form methods. Simulations demonstrate the good performance of the developed algorithm. (C) 2012 Elsevier B.V. All rights reserved.

关键词： 竞业限制协议   用人单位   责任竞合   违约责任   实务处理   违反   劳动者   诉权  

摘要： 一、问题的提出 周某于2008年3月进入A测试公司从事销售工作。双方签订了商业秘密保护及竞业限制协议，对周某的竞业限制义务作了约定，并约定：周某违反竞业禁止条款的，所得全部收益应当归A测试公司所有，并根据其从事竞业的自然月数，按照每月双倍于其在A测试公司任职期间月工资的标准向A测试公司支付违约金：违约金不足以弥补A测试公司损失的，A测试公司有权进一步追偿。

关键词： 微生物检验   医院感染   监控   临床意义  

摘要： 目的:对微生物检验在医院感染监控中的作用进行分析。方法:选取2010年5月-2012年7月医院收治的在医院进行就诊的患者68例;随机分为两组,甲组患者32例,采用常规性护理方法;乙组患者36例,在常规护理基础上,采用微生物针对检验进行监控护理,对比两组患者感染现象。结果:乙组患者在住院治疗期间的微生物感染情况显著高于甲组患者,差异性显著,具有统计学意义(P<0.05)。结论:对患者进行微生物检验检测,能有效预防医院感染,并及时发现和治疗。

关键词： 道路交通事故   物证检验鉴定  

摘要： 以道路交通事故所具有的特点及事故处理中常见问题为基础,阐述物证检验鉴定结论在道路交通事故中的作用。

关键词： 食品   标准菌株   质量控制  

摘要： 在微生物检验工作中常需要使用标准菌种作为阳性或阴性对照,本文根据食品微生物检验的特点及保种目的,探讨了标准菌种的购买、验收、标识、转种、确认、领取及销毁等程序,规范了标准菌种管理以保证其来源的可靠性和溯源性。

关键词： 债券市场   违约处理   人大   侧记   个人投资者   投资群体   可能性   公司债  

摘要： 虽然这并不是中国债市上首次债券持有人大会．却是继”福禧事件”后最受市场关注的一场债券持有人大会，不仅因为“11超日债”被视为可能性最高的债券市场”违约第一单”，还因为这只公司债的投资群体包括众多的个人投资者。

关键词： 贫血   血液检验   鉴别诊断  

摘要： 贫血在临床上是一种常见的症状，其定义是在单位容积的循环血液中，红细胞的数量、红细胞比积与血红蛋白量均小于正常值，并且伴随全血容量的减少，导致出现综合的症状。各个系统的疾病都有可能导致贫血。临床上，营养不良性的贫血主要包括缺铁性与巨幼细胞性2种类型，而巨幼红细胞性是最为常见的一种营养不良性贫血，经常危及患者的发育及身体的健康。

关键词： 溶血现象   干扰作用   生化检验  

摘要： 目的探讨、分析溶血现象在生化检验中的干扰作用。方法以2012年7月至2012年8月期间于我院检验科进行生化检验的60例正常人为研究对象,观察未溶血及溶血后标本的谷丙转氨酶(ALT)、总胆红素(TBIL)、谷草转氨酶(AST)、总蛋白(TP)、总胆固醇(CHO)、葡萄糖(GLU)、尿酸(UA)、三酰甘油(TG)、尿素氮(BUN)、乳酸脱氢酶(LDH)等10项常见的生化指标,并对各指标进行统计学分析,比较标本溶血前、后各检测指标的差异。结果标本中溶血前、后ALT、TBIL、AST、TP、GLU、UA、LDH的含量存在比较显著的差异,但是溶血对TG、CHO、BUN的检测值几乎无影响。结论溶血现象对生化检验的很多指标都有干扰作用,排除溶血的干扰对检验结果的准确性至关重要。