IEEE Trans Neural Netw
September 2007
The support vector machine (SVM) has been demonstrated to be a very effective classifier in many applications, but its performance is still limited as the data distribution information is underutilized in determining the decision hyperplane. Most of the existing kernels employed in nonlinear SVMs measure the similarity between a pair of pattern images based on the Euclidean inner product or the Euclidean distance of corresponding input patterns, which ignores data distribution tendency and makes the SVM essentially a "local" classifier. In this paper, we provide a step toward a paradigm of kernels by incorporating data specific knowledge into existing kernels.
View Article and Find Full Text PDFThe generalization error bounds found by current error models using the number of effective parameters of a classifier and the number of training samples are usually very loose. These bounds are intended for the entire input space. However, support vector machine (SVM), radial basis function neural network (RBFNN), and multilayer perceptron neural network (MLPNN) are local learning machines for solving problems and treat unseen samples near the training samples to be more important.
View Article and Find Full Text PDFObesity is an important risk factor for a cluster of metabolic and cardiovascular diseases, including insulin resistance, Type 2 diabetes, nonalcoholic fatty liver disease and atherosclerosis. Systemic low-grade inflammation, characterized by elevated circulating concentrations of proinflammatory factors, has recently been proposed to be a key mediator that links obesity with its medical complications. Adipose tissue is now recognized as the major contributor to systemic inflammation associated with obesity.
View Article and Find Full Text PDFHigh-resolution 1H NMR spectroscopy as a complementary method in the analysis of human bone marrow fatty acid (FA) composition was examined. Marrow FA composition in 10 bone samples measured by NMR and gas chromatography (GC) were compared. NMR T1 relaxation time of FA was determined and reproducibility tests were performed to assess the variability.
View Article and Find Full Text PDFPurpose: To prospectively determine the diagnostic accuracy of diffusion-weighted magnetic resonance (MR) imaging for discrimination of malignant neck nodes due to lymphoma, squamous cell carcinoma (SCC), and undifferentiated nasopharyngeal carcinoma (NPC), with histologic findings and imaging criteria as reference standards.
Materials And Methods: Ethics committee approval and informed consent were obtained. Patients with malignant lymphadenopathy underwent 1.
This study examined age-related emotional responses and coping at the peak and the end of the SARS outbreak in Hong Kong. Three hundred and eighty-five Hong Kong Chinese, aged 18-86 years, rated the extent that they experienced 'shock', 'sadness', 'anger' and 'fear' in the face of SARS. They also completed selected items from Brief COPE (Carver, 1997).
View Article and Find Full Text PDFIn owl monkeys, the typical retroviral restriction factor of primates, TRIM5alpha, is replaced by TRIMCyp. TRIMCyp consists of the TRIM5 RING, B-box 2 and coiled-coil domains, as well as the intervening linker regions, fused with cyclophilin A. TRIMCyp restricts infection of retroviruses, such as human immunodeficiency virus (HIV-1) and feline immunodeficiency virus (FIV), with capsids that can bind cyclophilin A.
View Article and Find Full Text PDFPrevious studies have found that in American culture high-arousal positive states (HAP) such as excitement are valued more and low-arousal positive states (LAP) such as calm are valued less than they are in Chinese culture. What specific factors account for these differences? The authors predicted that when people and cultures aimed to influence others (i.e.
View Article and Find Full Text PDFInt J Radiat Oncol Biol Phys
September 2007
Purpose: To determine whether the standard techniques of measuring tumor size and change in size after treatment could be applied to the measurement of nasopharyngeal cancers, which are often irregular in shape.
Methods And Materials: The standard measurements of bidimensional (BDM) (World Health Organization criteria) and unidimensional (UDM) (Response Evaluation Criteria in Solid Tumors [RECIST] criteria), together with the maximum depth of the tumor perpendicular to the pharyngeal wall (DM), were acquired from axial magnetic resonance images of primary nasopharyngeal carcinoma in 44 patients at diagnosis and in 29 of these patients after treatment. Tumor volume measurements (VM), acquired from the summation of areas from the axial magnetic resonance images, were used as the reference standard.
Arterioscler Thromb Vasc Biol
August 2007
Objective: Adipocyte fatty acid-binding protein (A-FABP) has been shown to be an important player in atherosclerosis in animal models. However, the clinical relevance of these findings is still unknown. This study aims to examine the relationship between serum A-FABP level and carotid intima-media thickness (IMT), an indicator of atherosclerosis in humans.
View Article and Find Full Text PDFUnlabelled: We have reported previously that (11)C-acetate ((11)C-ACT) PET was complementary to (18)F-FDG PET in the evaluation of primary hepatocellular carcinoma (HCC) in relation to the degree of tumor cellular differentiation. In this retrospective study, our goals were to further explore the complementary role of (11)C-ACT and (18)F-FDG PET in the detection of metastatic HCC disease, to evaluate the tracer characteristics of individual organ metastasis, to identify the risk factors of metastasis, and to evaluate how these results could affect patient management.
Methods: One hundred twenty-one patients were selected for this study.
Flavonoids are polyphenolic compounds that are widespread in the plant kingdom, and structure-activity relationships (SAR) for vascular relaxation effects were examined for 17 of them using porcine coronary arteries. Density functional theory was employed to calculate the chemical parameters of these compounds. The order of potency for vascular relaxation was as follows: flavones (apigenin and luteolin) >or= flavonols (kaempferol and quercetin)>isoflavones (genistein and daidzein)>flavanon(ol)es (naringenin)>chalcones (phloretin)>anthocyanidins (pelargonidin)>flavan(ol)es ((+)-catechin and (-)-epicatechin).
View Article and Find Full Text PDFBackground: Adipocyte-fatty acid binding protein (A-FABP), a major cytoplasmic protein in adipocytes, plays a central role in the development of diabetes and atherosclerotic cardiovascular disease in experimental animals. We have previously shown that A-FABP is present in the bloodstream and that its circulating levels correlate with metabolic risk factors in a cross-sectional study. In the present study, we further evaluated the prospective association of A-FABP with the metabolic syndrome (MetS) as defined by the updated National Cholesterol Education Program criteria.
View Article and Find Full Text PDFRadiotherapy is used to treat a wide variety of head and neck tumours that arise in and around the skull base. The delayed effects of radiation damages a range of structures, including the nervous system, bone, major vessels, mucus membranes, pituitary and salivary glands, as well as increasing the risk of radiation-induced neoplasms. In this review the complications resulting from radiation treatment for nasopharyngeal carcinoma (NPC), a cancer treated with a high dose of radiation to a fairly large region, are illustrated.
View Article and Find Full Text PDFConf Proc IEEE Eng Med Biol Soc
September 2008
A nonlinear canonical correlation analysis (CCA) for detecting neural activation in fMRI data is proposed in this paper. We use the BOLD response based on the HDR models with various parameters as reference signals. Instead of characterizing the relationship between the paradigm and time series using the oversimplified linear model, we employ the kernel trick that maps the intensities of the voxels within a small cubic at each time point into a high-dimensional kernel space, where the linear combinations correspond to nonlinear ones in the original space.
View Article and Find Full Text PDFWhile distance function learning for supervised learning tasks has a long history, extending it to learning tasks with weaker supervisory information has only been studied recently. In particular, some methods have been proposed for semisupervised metric learning based on pairwise similarity or dissimilarity information. In this paper, we propose a kernel approach for semisupervised metric learning and present in detail two special cases of this kernel approach.
View Article and Find Full Text PDFCurrently fielded treatments for nerve agent intoxication promote survival, but do not afford complete protection against either nerve agent-induced motor and cognitive deficits or neuronal pathology. The use of human plasma-derived butyrylcholinesterase (HuBuChE) to neutralize the toxic effects of nerve agents in vivo has been shown to both aid survival and protect against decreased cognitive function after nerve agent exposure. Recently, a commercially produced recombinant form of human butyrylcholinesterase (r-HuBuChE; PharmAthene Inc.
View Article and Find Full Text PDFThe one-class classification problem aims to distinguish a target class from outliers. The spherical one-class classifier (SOCC) solves this problem by finding a hypersphere with minimum volume that contains the target data while keeping outlier samples outside. SOCC achieves satisfactory performance only when the target samples have the same distribution tendency in all orientations.
View Article and Find Full Text PDFGender differences in social network characteristics are well documented in the literature. Socio-emotional selectivity theory emphasizes the importance of future time perception on selection of social partners whereas cultural studies stress the roles of Renqing (relationship orientation) on social interactions. This study examined the effects of future time perspective and adherence to Renqing on social network characteristics, and their associations with psychological well-being of 321 Chinese men and women, aged 28-91 years.
View Article and Find Full Text PDFNucleophosmin-anaplastic lymphoma kinase (NPM-ALK) expression is associated with the lymphoid malignancy anaplastic large cell lymphoma (ALCL) and results from a t(2;5) chromosomal translocation. We show that NPM-ALK induces Ras activation and phosphorylation of the ERK MAP Kinase consistent with activation of the Ras-MAP Kinase pathway. Furthermore, we demonstrate that activation of Ras is necessary for inducing transcription via NFAT/AP-1 composite transcriptional binding sites.
View Article and Find Full Text PDFBackground: Nucleophosmin-anaplastic lymphoma kinase expression is associated with a lymphoid malignancy, anaplastic large cell lymphoma, and is characterized by a t(2;5) chromosomal translocation.
Materials And Methods: We describe a novel transgenic mouse line in which NPM-ALK expression is targeted to the T-cell lineage using the CD2 promoter.
Results: Surprisingly, the mice develop B cell lymphomas in the majority of cases.
Purpose: To prospectively study the relationship among vertebral marrow fat content, marrow diffusion indexes, and marrow and erector spinae muscle perfusion indexes in female subjects with varying bone mineral density.
Materials And Methods: Institutional study approval and informed consent were obtained. Dual x-ray absorptiometry, proton magnetic resonance (MR) spectroscopy, diffusion-weighted MR imaging, and dynamic contrast material-enhanced MR imaging of the lumbar spine and erector spinae muscle were performed in 110 women (mean age, 73 years; range, 67-84 years).
Breast Cancer Res Treat
September 2007
In vivo proton magnetic resonance spectroscopy ((1)H-MRS) has been demonstrated to be successful in the differentiation of benign and malignant breast lesions in a non-invasive manner by detecting increased levels of composite choline (Cho) compounds. Currently there is molecular evidence of increased Cho metabolism in breast cancer cells. In breast malignancies, (1)H-MRS achieved a high-overall sensitivity (82%).
View Article and Find Full Text PDFBreast Cancer Res Treat
May 2007
Magnetic resonance imaging of the breast is useful in assessing breast lesions. An understanding of the pathologic characteristics of the tumors may help to understand these magnetic resonance imaging observations.Large lesional size (>10 mm), ill-defined margin, and irregular outlines are associated with malignancy.
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