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关键词： Shibor   基准性   货币政策   利率传导   利率体系   信贷渠道   市场基准利率   价格型   联动性   传导渠道  

摘要： 本文在系统综述国内外相关研究成果的基础上,分别从市场性、稳定性、相关性以及基础性四个方面对Shibor、全国银行间同业拆借利率(Ibor)、银行间质押式国债回购利率(Repo)以及商业银行定期存款利率(Or)的基准性进行了检验与比较。结果表明,与其它三个利率体系相比,Shibor的基准性更强,可以作为我国市场利率体系的基准利率。在此基础上,本文分别从市场利率与货币政策工具变量的联动性和市场利率对实体经济变量的传递效应两个方面,对Shibor在我国货币政策传导机制中的作用进行了分析。结果表明,Shibor能够更好地在我国货币政策的利率传导机制中发挥作用,对货币政策工具的变动更为敏感,并主要通过信贷渠道影响实体经济增长。最后,本文就如何进一步完善Shibor利率体系提出了五点政策建议。

关键词： Support vector machines   Neural networks   Oral malodor classification   METHYL MERCAPTAN   DIVERSITY  

摘要： Objective: This study presents an effective method of classifying oral malodor from oral microbiota in saliva by using a support vector machine (SVM), an artificial neural network (ANN), and a decision tree. This approach uses concentrations of methyl mercaptan in mouth air as an indicator of oral malodor, and peak areas of terminal restriction fragment (T-RF) length polyrnorphisms (T-RFLPs) of the 16S rRNA gene as data for supervised machine-learning methods, without identifying specific species producing oral malodorous compounds. Methods: 1 6S rRNA genes were amplified from saliva samples from 309 subjects, and T-RFLP analysis was carried out with the DNA fragments. T-RFLP analysis provides information on microbiota consisting of fragment lengths and peak areas corresponding to bacterial strains. The peak area is equivalent to the frequency of a specific fragment when one molecule is selected from terminal fragments. Another frequency is obtained by dividing the number of species-containing samples by the total number of samples. An SVM, an ANN, and a decision tree were trained based on these two frequencies in 308 samples and classified the presence or absence of methyl mercaptan in mouth air from the remaining subject. Results: The proportion that trained SVM expressed as entropy achieved the highest classification accuracy, with a sensitivity of 51.1% and specificity of 95.0%. The ANN and decision tree provided lower classification accuracies, and only classification by the ANN was improved by weighting with entropy from the frequency of appearance in samples, which increased the accuracy to 81.9% with a sensitivity of 60.2% and a specificity of 90.5%. The decision tree showed low classification accuracy under all conditions. Conclusions: Using T-RF proportions and frequencies, models to classify the presence of methyl mercaptan, a volatile sulfur-containing compound that causes oral malodor, were developed. SVM classifiers successfully classified the presence

关键词： machine learning   maximum likelihood classification   logistic regression   support vector machine   tree classifiers   random forests   COVER CLASSIFICATION   REQUIREMENTS   TM  

摘要： Although a large number of new image classification algorithms have been developed, they are rarely tested with the same classification task. In this research, with the same Landsat Thematic Mapper (TM) data set and the same classification scheme over Guangzhou City, China, we tested two unsupervised and 13 supervised classification algorithms, including a number of machine learning algorithms that became popular in remote sensing during the past 20 years. Our analysis focused primarily on the spectral information provided by the TM data. We assessed all algorithms in a per-pixel classification decision experiment and all supervised algorithms in a segment-based experiment. We found that when sufficiently representative training samples were used, most algorithms performed reasonably well. Lack of training samples led to greater classification accuracy discrepancies than classification algorithms themselves. Some algorithms were more tolerable to insufficient (less representative) training samples than others. Many algorithms improved the overall accuracy marginally with per-segment decision making.

关键词： HIGH HYDROSTATIC-PRESSURE   DIFFERENTIAL SCANNING CALORIMETRY   PENETRANT-INDUCED PLASTICIZATION   MASS-TRANSFER PROPERTIES   SORBED CARBON-DIOXIDE   GLASSY-POLYMERS   MECHANICAL-PROPERTIES   TRANSMITTING FLUIDS   BARRIER PROPERTIES   VOLATILE COMPOUNDS  

摘要： As high-pressure processing is used increasingly for the treatment of packed products, different packaging has been investigated with respect to their structural behaviour and stability under high-pressure processing. Often, failures and changes of the polymeric structure occur. Common damage symptoms of high-pressure-treated packaging materials are defined and classified in this review. These damage symptoms are allocated to the physico-chemical effects that created them. The effects may be separated into direct effects induced by the action of the high-pressure alone and indirect effects that are mediated via compressed contents of the package, i.e. filled product and gaseous headspace. The direct effects split up again in reversible and irreversible structural changes. The indirect effects are generated by compressed headspace gases, other compressed substances and the consequences of increased amounts of gases dissolved in the polymers. If applicable, current theoretical approaches have been allocated to the different categories of damage. Copyright ? 2013 John Wiley & Sons, Ltd.

关键词： Drying   Heat transfer   Local evaporation rate   Mass transfer   Mathematical modeling   Reaction engineering approach (REA)   Sample thickness effect   COMPUTATIONAL FLUID-DYNAMICS   MASS-TRANSFER   MOISTURE TRANSPORT   HIGH-TEMPERATURE   DRYING KINETICS   SPRAY DRYER   DIFFUSION-COEFFICIENT   FOOD MATERIALS   BIOT-NUMBER   MILK POWDER  

摘要： The reaction engineering approach (REA) is examined here to investigate its suitability as the local evaporation rate to be used in multiphase drying. For this purpose, REA is first implemented to model the convective drying of materials with various thicknesses. The relative activation energy, as the fingerprint of REA, generated from one size of a material is used to model the convective drying of the same material with different thicknesses. Because the results indicate that REA parameters can model the drying of materials with various thicknesses, REA can be scaled down to describe the local evaporation rate (at the microscale as affected by local composition and temperature). The relative activation energy is used to describe the global drying rate in modeling the local evaporation rate. REA is combined with a system of equations of conservation of heat and mass transfer in order to yield the spatial reaction engineering approach (S-REA) as a nonequilibrium multiphase drying model. By using S-REA, the spatial profiles of moisture content, concentration of water vapor, temperature, and local evaporation rate can be generated, which can assist in comprehending the transport phenomena.

关键词： Anti-drug antibody   Confirmatory   Cut point   Immunoassay   Specificity   BIOTECHNOLOGY PRODUCTS   HOST ANTIBODIES   CUT POINTS   RECOMMENDATIONS  

摘要： Biotechnology-derived therapeutics may induce an unwanted immune response leading to the formation of anti-drug antibodies (ADAs) which can result in altered efficacy and safety of the therapeutic protein. Anti-drug antibodies may, for example, affect pharmacokinetics of the therapeutic protein or induce autoimmunity. It is therefore crucial to have assays available for the detection and characterization of ADAs. Commonly, a screening assay is initially used to classify samples as either ADA positive or negative. A confirmatory assay, typically based on antigen competition, is subsequently employed to separate false positive samples from truly positive samples. In this manuscript we investigate the performance of different statistical methods classifying samples in competition assays through simulation and analysis of real data. In our evaluations we do not find a uniformly best method although a simple t-test does provide good results throughout. More crucially we find that very large differences between uninhibited and inhibited measurements relative to the assay variability are required in order to obtain useful classification results questioning the usefulness of competition assays with high variability. (C) 2013 Elsevier B.V. All rights reserved.

关键词： SURFACE-PLASMON RESONANCE   ARRAYED IMAGING REFLECTOMETRY   MYOTONIC-DYSTROPHY   CUG REPEATS   PROTEIN   KINETICS   RECOGNITION   LIGANDS   BINDING   STRATEGIES  

摘要： The near-ubiquity of the involvement of RNA in crucial biological processes is accepted. It is important, therefore, to study and understand the biophysical principles that regulate the function of RNA and its interactions with other molecules (e.g., proteins and antibiotics). Methods enabling the high-throughput determination of RNA-protein binding kinetics and thermodynamics would greatly accelerate understanding of these interactions. To that end, we describe the development of a real-time biomolecular interaction analysis platform based on arrayed imaging reflectometry (AIR) for multiplex analysis of RNA-protein interactions. We demonstrate the use of aqueous AIR by measuring the binding kinetics between muscleblind-like 1 (MBNL1), a splicing regulator protein that plays a pivotal role in the Myotonic Dystrophies and Huntington's Disease, and several of its RNA targets simultaneously on a microarrayed chip. Using this approach, we observe that the kinetics of MBNL1 binding isolated CUG and repeat CUG RNA sequences (as models for "normal" and "pathogenic" RNA, respectively) are different even though their steady state binding constants are similar. The ability to compare binding kinetics between RNA sequences rapidly and easily may provide insight into the molecular basis of MBNL1-RNA binding, and more generally suggests that AIR can be a powerful tool to enable the label-free, real-time analysis of biomolecular interactions in a high-throughput format.

关键词： ceria   DFT plus U   hybrid functional   HSE06   catalysis   OXYGEN VACANCY FORMATION   TRANSITION-METAL   SUBSTITUTED CEO2   PLUS U   ADSORPTION   ACTIVATION   ENERGIES   INSIGHT   OXIDES  

摘要： For CeO2 or M-doped CeO2 catalysts, reliable energetics associated with surface reactivity requires accurate representation of oxidized and reduced metal states. Density functional theory (DFT) is used extensively for metals and metal oxides; however, for strongly correlated electron materials, conventional DFT fails to predict both qualitative and quantitative properties. This is the result of a localized electron self-interaction error that is inherit to DFT. DFT+U has shown promise in correcting energetic errors due to the self-interaction error, however, its transferability across processes relevant to surface catalysis remains unclear. Hybrid functionals, such as HSE06, can also be used to correct this self-interaction error. These hybrid functionals are computationally intensive, and especially demanding for periodic surface slab models. This perspective details the challenges in representing the energetics of M-doped ceria catalyzed processes and examines using DFT extensions to model the localized electronic properties. (c) 2013 Wiley Periodicals, Inc.

关键词： 资源寻求   量表编制   调节作用   同伴帮助关系   人力资源管理   领导支持  

摘要： 资源在员工完成工作任务和实现未来发展中起到十分重要的作用。以往研究更多地讨论了组织为员工提供资源的重要性，但针对员工自身如何主动获取资源并没有系统的研究。本研究针对这一方面的空缺，根据工作要求-资源理论，提出资源寻求的定义，即个体主动向工作关系中的他人寻求有助于完成工作任务和个体发展的额外资源，并与已有资源进行整合以便充分利用、提高工作效能的过程。进一步，我们根据资源寻求的内容，将其分为信息资源寻求和情感资源寻求两个维度。以资源寻求的概念以及信息资源寻求和情感资源寻求为基础，本研究编制了资源寻求问卷，并对问卷进行一系列检验。预实验通过探索性因素分析对资源寻求量表的二因素模型进行检验。实验一以302名工程技术人员为样本，利用验证性因素分析对资源寻求的二因素模型进行验证，以同伴帮助、工作满意度和工作绩效为指标，检验资源寻求及其两个维度的预测效度，并通过因素分析对资源寻求和主动性人格进行区分。实验二以568名呼叫中心客服员工为样本，检验资源寻求及两个维度在转换型领导与领导支持和同伴帮助关系中的调节作用。\n 研究结果发现，1）探索性因素分析支持了资源寻求中信息资源寻求和情感资源寻求两个因素;2）验证性因素分析证实了资源寻求的二因素模型;3）在控制了外向性、宜人性和开放性后，资源寻求与同伴帮助、工作满意度和工作绩效正相关，其中信息资源寻求对同伴帮助、工作满意度和工作绩效的预测显著，情感资源寻求对同伴帮助的预测显著;4）资源寻求在转换型领导与领导支持和同伴帮助的关系中起调节作用，资源寻求水平高时，转换型领导与领导支持和同伴帮助正相关更强。信息资源寻求在转换型领导与领导支持关系中的调节作用显著，在转换型领导与同伴帮助关系中的调节作用不显著。文章最后对研究结果及其理论和实践意义进行了讨论。

关键词： 合同订立   推定形式   口头形式   合同成立   自动售货机   现货交易   买卖合同   合同纠纷   受害方  

摘要： 法律规定合同订立方式有口头形式、书面形式、推定形式三种。一、口头形式口头形式在日常生活中经常被采用。集市的现货交易、商店里的零售等一般都采用口头形式。二、书面形式合同书以及任何记载当事人要约、承诺和权利义务内容的文件,都是合同书面形式的具体表现。三、推定形式推定形式,是当事人未用语言、文字表达其意思表示,仅用行为向对方发出要约,对方接受该要约,作出一定或指定的行为作为承诺的,合同成立。例如商店安装自动售货机,顾客将规定的货币投入机器内,