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关键词： 新闻图像   新闻量表   新闻图像作用   社会舆论  

摘要： 新闻图像作用量表能够告诉受众自己为什么受新闻图像影响,以及在哪些方面受到其影响;也可以使新闻图像传播者在传播实践中更有的放矢或规范自己的传播行为。而在此基础上编制的新闻图像作用判定量表则进一步为新闻媒体图像编辑等把关人在选用图像时以及制定图像传播策略时提供具体操作方法。

关键词： autocatalysis   asymmetric amplification   asymmetric catalysis   chirality   origin of homochirality  

摘要： Pyrimidyl alkanol was found to act as an asymmetric autocatalyst in the enantioselective addition of diisopropylzinc to pyrimidine-5-carbaldehyde. Asymmetric autocatalysis of 2-alkynylpyrimidyl alkanol with an extremely low enantiomeric excess (ca. 0.00005% ee) exhibits enormous asymmetric amplification to afford the same compound with >99.5% ee. This asymmetric autocatalysis with amplification of ee has been employed to examine the validity of proposed theories of the origins of homochirality. Circularly polarized light, quartz, sodium chlorate, cinnabar, chiral organic crystals and spontaneous absolute asymmetric synthesis were considered as possible candidates for the origin of chirality;each could act as a chiral source in asymmetric autocatalysis. Asymmetric autocatalysis can discriminate the isotope chirality arising from the small difference between carbon (carbon-13/carbon-12) and hydrogen (D/H) isotopes. Cryptochiral compounds were also discriminated by asymmetric autocatalysis.

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

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： CBC   Ethylenediaminetetraacetic acid   Macrocytes   Neutropenia   Relative lymphocytosis  

摘要： Collection of lower sample volumes into dipotassium ethylenediaminetetraacetic acid (K2EDTA) containers, according to the manufacturers" data and current Clinical and Laboratory Standards Institute, results in erroneous haematology results. To proof this we collected acceptable limit of lower sample volumes for haematology analyses into the 4.0ml standard spray-dried K2EDTA. 9.0ml of blood from 15 retroviral volunteers was collected and each donation was aliquot into the following volumes 4.0, 2.0, 1.5, 1.0, 0.5ml. These samples were analyzed within 4hrs of collection on Sysmex KX-21N haematology analyzer for complete blood count (CBC) including leukocytes differentials. T-test showed there was no significant difference between results of lower samples volumes and the standard volume and regression analysis showed excellent correlation for all parameters. Lower sample collection volumes compared to the standard volume showed negative bias for platelet count but the difference was considered insignificant with percentage differences of 4.6%, 3.0%, 2.9%, and 1.7% for 1.0, 1.5, 0.5, and 2.0ml collection volumes respectively. Flag messages were noticed in about 67.0% of the patients irrespective of collection volumes. Acceptable CBC values for spray-dried K2EDTA collection tubes containing lower sample volumes can be obtained with as little as 1.0ml in Nigerian subjects.

关键词： High-pressure processing   packaging   headspace   crystallinity   polymer  

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： Support vector machines   Neural networks   Oral malodor classification  

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： Drying   Heat transfer   Local evaporation rate   Mass transfer   Mathematical modeling   Reaction engineering approach (REA)   Sample thickness effect  

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  

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： RNA splicing   NUCLEOTIDE sequence   PROTEIN binding   REFLECTOMETRY   MICROARRAY technology  

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  

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.