Fu Jen Catholic University

About: Fu Jen Catholic University is a education organization based out in Taipei, Taiwan. It is known for research contribution in the topics: Population & Medicine. The organization has 6842 authors who have published 9512 publications receiving 171005 citations. The organization is also known as: FJU & Fu Jen.

Double Nearest Proportion Feature Extraction for Hyperspectral-Image Classification

Abstract: For the classification among different land-cover types in a hyperspectral image, particularly in the small-sample-size situation, a feature-extraction method is an approach for reducing the dimensionality and increasing the classification accuracy. Fisher's linear discriminant analysis (LDA) is one of the most popular feature-extraction methods. However, it cannot be applied directly to the classification of hyperspectral image because of several natures of Fisher's criterion. Nonparametric discriminant analysis (NDA) and nonparametric weighted feature extraction, on the other hand, are two extensions of LDA with a creative idea about emphasizing the boundary structure of class distributions. However, the overlap situation was not considered in these methods and thus decreased the robustness of these methods. In this paper, a new feature-extraction method is introduced based on a structure named double nearest proportion. This structure enables the proposed method to reduce the effect of overlap, allows a new regularization technique to be embedded, and includes LDA and NDA as special cases. These properties enable the proposed method to be more robust and thus, generally, have better performance.

Fluoxetine depresses glutamate exocytosis in the rat cerebrocortical nerve terminals (synaptosomes) via inhibition of P/Q-type Ca2+ channels

Abstract: Fluoxetine, an antidepressant that is used clinically in the treatment of mood disorders, is a selective serotonin reuptake inhibitor. In the present study we investigated the effects of fluoxetine on 4-aminopyridine (4AP)-evoked glutamate release in cerebrocortical nerve terminals (synaptosomes). Fluoxetine suppressed the release of glutamate evoked by 4AP in a concentration-dependent manner. This effect was associated with a reduction in the depolarization-evoked increase in cytosolic free calcium levels in the absence of significant effect on the synaptosomal membrane potential. In addition, both ionomycin- and sucrose-evoked glutamate releases were not affected by fluoxetine, indicating that fluoxetine-mediated inhibition of glutamate release is not a direct effect on the exocytotic machinery. Furthermore, the inhibitory action of fluoxetine was completely abolished in synaptosomes pretreated with P/Q type Ca(2+) channel blocker omega-agatoxin IVA (omega-AgTX IVA) or protein kinase C (PKC) stimulator 4beta-phorbol 12, 13-dibutyrate (PDBu). These results suggest that, in cerebrocortical nerve terminals, fluoxetine inhibits glutamate release through the suppression of P/Q type Ca(2+) channel activity. The presynaptic action of fluoxetine is mediated by a PKC-sensitive signaling pathway. Synapse 48:170-177, 2003.

Mitochondrial DNA Content Varies with Pathological Characteristics of Breast Cancer

Abstract: Changes in mitochondrial DNA (mtDNA) content in cancers have been reported with controversial results, probably due to small sample size and variable pathological conditions. In this study, mtDNA content in 302 breast tumor/surrounding normal tissue pairs were evaluated and correlated with the clinico-pathological characteristics of tumors. Overall, mtDNA content in tumor tissues is significantly lower than that in the surrounding normal tissues, . MtDNA content in tumor tissues decreased with increasing tumor size. However, when the tumor is very large (>50 cm3), mtDNA content started to increase. Similarly, mtDNA content decreased from grades 0 and I to grade II tumors, but increased from grade II to grade III tumors. Tumors with somatic mtDNA alterations in coding region have significantly higher mtDNA content than tumors without somatic mtDNA alterations (). Tumors with somatic mtDNA alterations in the D-Loop region have significantly lower mtDNA content (). Patients with both low and high mtDNA content in tumor tissue have significantly higher hazard of death than patients with median levels of mtDNA content. mtDNA content in tumor tissues change with tumor size, grade, and ER/PR status; significant deviation from the median level of mtDNA content is associated with poor survival.

Field-induced polarization rotation in (001)-cut Pb(Mg1/3Nb2/3)0.76Ti0.24O3

Abstract: Polarization rotation of field-induced phase transformations was observed by means of a polarizing microscope on a (001)-cut single crystal $\mathrm{Pb}({\mathrm{Mg}}_{1/3}{\mathrm{Nb}}_{2/3}{)}_{0.76}{\mathrm{Ti}}_{0.24}{\mathrm{O}}_{3}$ (PMNT24%) at room temperature with an electric field applied along the [001] direction. A hysteresis loop was also measured for comparison. As the electric field increases, polarizations of rhombohedral $R$ domains rotate toward the [001] tetragonal ${T}_{001}$ phase through ${M}_{A}$-type monoclinic distortions, i.e., $\stackrel{\ensuremath{\rightarrow}}{R}{M}_{A}\ensuremath{\rightarrow}{T}_{001}.$ The crystal cannot entirely reach the ${T}_{001}$ phase as the field approaches 44 kV/cm. In addition, spotlike domains that perhaps correspond to ${M}_{B}$-type monoclinic or triclinic phases were also observed. This field-induced phase transformation is strongly irreversible.