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| 1 | 基于类别空间的基因选择显示文摘基因选择通常是在基因空间中进行的.由于基因空间的维数(基因数目)比该空间中的样本数要多得多,这种做法存在严重的维数发难(curse of dimensionality)问题,其结果是在基因空间中所建立数据模型难于获得满意的精度,基于所建立模型的基因选择结果可信度低.如何对具有极少样本的极高维空间进行特征选择(基因选择)是一个极具挑战性的课题.将基因空间变换为它的对偶空间,称为类别空间,从而空间的维数仅为基因空间中样本的类别数,空间中的样本数则为基因空间的维数.显然,在类别空间中不存在任何维数发难现象;提出了在类别空间中基于将不同的类尽可能分开的原则、并借助主分量分析的基于类别空间基因选择方法.对真实基因数据的基因选择实验,并通过Fisher指标、加权Fisher指标以及leave-one-out cross validation等可分性指标,与其他两种基因选择方法进行了深入的比较,结果表明该方法是十分有效的. | 张军英 Y.J.Wang J.Khan R.Clarke | 2003 | 中国科学(E辑)2003，33，12： | 9 |
| 2 | Chopper-modulated gas chromatography electroantennography enabled using high-temperature MEMS flow control device显示文摘We report the design,fabrication and characterization of a microelectromechanical systems(MEMS)flow control device for gas chromatography(GC)with the capability of sustaining high-temperature environments.We further demonstrate the use of this new device in a novel MEMS chopper-modulated gas chromatography-electroantennography(MEMS-GC-EAG)system to identify specific volatile organic compounds(VOCs)at extremely low concentrations.The device integrates four pneumatically actuated microvalves constructed via thermocompression bonding of the polyimide membrane between two glass substrates with microstructures.The overall size of the device is 32 mm×32 mm,and it is packaged in a 50 mm×50 mm aluminum housing that provides access to the fluidic connections and allows thermal control.The characterization reveals that each microvalve in the flow control chip provides an ON to OFF ratio as high as 1000:1.The device can operate reliably for more than 1 million switching cycles at a working temperature of 300℃.Using the MEMS-GC-EAG system,we demonstrate the successful detection of cis-11-hexadecenal with a concentration as low as 1 pg at a demodulation frequency of 2 Hz by using an antenna harvested from the male Helicoverpa Virescens moth.In addition,1μg of a green leafy volatile(GLV)is barely detected using the conventional GC-EAG,while MEMS-GC-EAG can readily detect the same amount of GLV,with an improvement in the signal-to-noise ratio(SNR)of~22 times.We expect that the flow control device presented in this report will allow researchers to explore new applications and make new discoveries in entomology and other fields that require high-temperature flow control at the microscale. | Ming-Da Zhou Muhammad Akbar Andrew J.Myrick Yiqiu Xia Waleed J.Khan Xiang Gao Thomas C.Baker Si-Yang Zheng | 2017 | Microsystems & Nanoengineering2017，3，1： | 2 |
| 3 | Socioeconomic status and the risk of cervical intraepithelial neoplasia grade 3 among oncogenic human papillomavirus DNA‐positive women with equivocal or mildly abnormal cytology显示文摘 | Michelle J.Khan Edward E.Partridge Sophia S.Wang MarkSchiffman | 2005 | Cancer2005，，1： | 1 |
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