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关键词： Blood cell classification   Leukemia diagnosis   Acute lymphocytic leukemia   Acute myeloid leukemia   Artificial neural networks  

摘要： Pattern recognition applied to blood samples for diagnosing leukemia remains an extremely difficult task which frequently leads to misclassification errors due in large part to the inherent problem of data overlap. A novel artificial neural network (ANN) algorithm is proposed for optimizing the classification of multidimensional data, focusing on acute leukemia samples. The programming tool established around the ANN architecture focuses on the classification of normal vs. abnormal blood samples, namely acute lymphocytic leukemia (ALL) and acute myeloid leukemia (AML). There were 220 blood samples considered with 60 abnormal samples and 160 normal samples. The algorithm produced very high sensitivity results that improved up to 96.67% in ALL classification with increased data set size. With this type of accuracy, this programming tool provides information to medical doctors in the form of diagnostic references for the specific disease states that are considered for this study. The results obtained prove that a neural network classifier can perform remarkably well for this type of flow-cytometry data. Even more significant is the fact that experimental evaluations in the testing phase reveal that as the ALL data considered is gradually increased from small to large data sets, the more accurate are the classification results.

关键词： Crude oils   Oil spills   Weathering   SOM   PCA   Discriminant PLS   Variable selection  

摘要： Weathering processes considerably change the chemical composition of crude oils spilled on the environment. The impact of this effect on the classification capabilities of Kohonen neural networks (self-organizing maps, SOM) trained to predict the geographical origin of crude oils, was studied. A set of 38 worldwide crude oils from six distinct geographical regions was considered and each product was weathered to build a database of 263 samples. Gas Chromatography-Mass Spectrometry was used to monitor weathering and to determine a suite of 22 ratios of PAHs (polycyclic aromatic hydrocarbons) and alkanes. which are currently considered resilient to weathering. Three different experiments were performed with SOMs to study the effect of oil weathering and analytical conditions on the final results: a) weathered and un-weathered samples were randomly distributed in the training and validation sets, b) the training set included only unweathered samples while the validation set consisted of all the weathered samples, and c) the operational conditions (instruments/technicians) were different for the samples of the training and validation sets. After training the different SOMs, the percentage of correct classifications was in the 83.8%-95.7% range for the validation sets. A consensus SOM associated to a confidence level is proposed in which the decision is taken based on the number of votes of the winning class. The lowest success on the classification of the most weathered samples was expected and can be explained easily by the important changes on the chromatographic profiles due to the disappearance of the lightest alkanes and the relative enrichment on the more substituted PAHs. Most incorrect classifications occurred because the samples activated neurons at the close neighbourhood of the regions where they should belong to. The 'consensus' approach improved the capability to predict unknown samples. Results were compared to those from discriminant partial least squares

关键词： Acceptance   Macroevolution   Understanding  

摘要： The goal of this research was to illuminate the relationship between students' acceptance and understanding of macroevolution. Our research questions were: (1) Is there a relationship between knowledge of macroevolution and acceptance of the theory of evolution?;(2) Is there a relationship between the amount of college level biology course work and acceptance of evolutionary theory and knowledge of macroevolution?;and (3) Can college student acceptance of the theory of evolution and knowledge of macroevolution change over the course of a semester? The research participants included 667 students from a first-semester biology course and 74 students from the evolutionary biology course. Data were collected using both the MATE (a measure of the acceptance of evolutionary theory) and the MUM (a measure of understanding of macroevolution). Pre-instruction data were obtained for the introductory biology course, and pre- and post-data were obtained for the evolutionary biology course. Analysis revealed acceptance of evolution (as measured by the MATE) was correlated to understanding of macroevolution, and the number of biology courses was significantly correlated to acceptance and knowledge of macroevolution. Finally, there was a statistically significant change in students' understanding of macroevolution and acceptance of evolution after the one-semester evolutionary biology course. Significance of these findings is discussed. © 2010 Springer Science+Business Media, LLC.

关键词： 新国标   一次性饭盒   检验   农贸市场   一次性餐具   可降解   塑料制作   纸质餐盒  

摘要： 在上海一些超市、快餐厅、小饭店、农贸市场等地方发现，装熟食的一次性餐具大多标明“可降解”。在虹桥路一家快餐厅，服务员用来打包的一次性饭盒是透明塑料制作的，店主表示这种饭盒“可降解”。在武宁路一家农贸市场，卖卤食的小贩用的是纸质餐盒，盒盖上也标着“可降解”……

关键词： 水电站   岩溶   枢纽布置   泄流消能   基础防渗   地震   滞洪削峰   通口水电站  

摘要： 2008年5月12日四川汶川发生8.0级地震,导致通口河中上游山体垮塌,在唐家山形成特大型堰塞湖,交通中断。建于典型岩溶地段的通口水电站大坝在堰塞湖下游约23km处,为碾压混凝土高坝,泄洪消能系统采用溢流表孔+宽尾墩+戽式消力池的方式。工程建在高烈度地区,距离震中较近,在汶川特大地震中震损轻微,防渗体系完好,在唐家山堰塞湖泄洪过程中的滞洪削峰为保护下游沿岸和城市发挥了很大的作用。本文对此进行了介绍。

关键词： 险验检疫联络员   完善   常态化  

摘要： 检验检疫联络员机制是检验检疫事业发展的客观需要，也是检验检疫机构和地方政府通力合作的成果，如何在建立大质检工作机制中，进一步完善检验检疫联络员机制，充分发挥检验检疫联络员的“宣传员”、“联络员”、“监督员”的作用，为企业提供更加优质高效的服务，更好的服务经济，值得我们思考。

关键词： 质量管理   检验科   临床标本检测   检测结果   循征医学   临床诊断   质量控制   科学性  

摘要： 随着循征医学的发展，临床标本检测的质量以及它在临床诊断中的所起的作用越来越重要。然而病人标本不同于其他标本，在一般情况下病人标本只随机或晨间采集一次。检验科通过这一次采样及对它的一次检测，就要求让检测结果能达到体内的真值，这种要求科学性较差。我们只能通过努力，采用各种质量控制的方法争取检测结果尽可能接近真值，尽可能客观地反映体内情况。

关键词： 包装设计   土特产品   装潢设计  

摘要： 本文对各种土特产品进行了包装分类、设计和定位;阐述了土特产包装应该融入地域文化、民族文化等因素以提高其文化内涵和品位,突出地方特色、民族特色,意义在于土特产品蕴含了文化因素,超越了产品本身的商业价值,我们用土特产品宣传地域文化,借地域文化特色来促进土特产品的销售,这样既能扩大经济效益又能弘扬地域文化。

关键词： 国际货物销售合同   合同形式   中国   法律适用   书面形式  

摘要： 一、中国国际货物销售合同形式的概念 就“国际货物销售合同的形式”而言，只能从“合同形式”的狭义上来理解。为本文研究之目的，“中国国际货物销售合同的形式”，仅限于中国国际货物销售合同的订立是否应当采取书面形式，无涉中国国际货物销售合同形式的具体种类。

关键词： Electromyography   Evoked contractions   Maximal voluntary contractions   Medial gastrocnemius   Soleus  

摘要： The present study aimed to investigate the immediate effects of 15 min static or sub-maximal contract-relax stretching modalities on the neuromuscular properties of plantar flexor muscles. Ten male volunteers were tested before and immediately after 15 min static or contract-relax stretching programs of plantar flexor muscles (20 stretches). Static stretching consisted in 30 s stretches to the point of discomfort. For the contract-relax stretching modality, subjects performed 6 s sub-maximal isometric plantar flexion before 24 s static stretches. Measurements included maximal voluntary isometric torque (MVT) and the corresponding electromyogsraphic activity of soleus (SOL) and medial gastrocnemius (MG) muscles (RMS values), as well as maximal peak torque (Pt) elicited at rest by single supramaximal electrical stimulation of the tibial nerve. After 15 min stretching, significant MVT and SQL RMS decreases were obtained (-6.9 +/- 11.6% and 6.5 +/- 15.4%, respectively). No difference was obtained between stretching modalities. Pt remained unchanged after stretching. MG RMS changes were significantly different between stretching modalities (-9.4 +/- 18.3% and +3.5 +/- 11.6% after static and contract-relax stretching modalities, respectively). These findings indicated that performing 15 min static or contract-relax stretching had detrimental effects on the torque production capacity of plantar flexor muscles and should be precluded before competition. Mechanisms explaining this alteration seemed to be stretch modality dependent. (C) 2009 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.