Browsing by Issue Date, starting with "2013-04-25"

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Evidence of securin-mediated resistance to gefitinib-induced apoptosis in human cancer cells
(2013-04-25)
Yu, Sheng-Yi
;
Liu, Huei-Fang
;
Wang, Su-Pei
;
Chang, Chia-Ching
;
Tsai, Chuan-Mei
Gefitinib, a tyrosine kinase inhibitor of the epidermal growth factor receptor (EGFR), has been used to treat numerous cancers; however, evidence has shown that cancer cells can become resistant to gefitinib during therapy. Here, we report a human proto-oncogene, securin, which displays resistance to death in cancer cells. Gefitinib treatment decreases securin levels at the protein level by inducing protein instability but did not affect on the securin gene expression. Treatment with gefitinib induced cytotoxicity in various human cancer cell types, including RKO (colon cancer), A549 (lung cancer), BFTC905 (bladder cancer), MCF7 (breast cancer) and A375 (skin cancer). BFTC905 and A549 cells expressed relatively high levels of the phosphorylated and total EGFR proteins; however, A375, MCF7 and RKO cells did not markedly express these proteins. Moreover, following treatment with gefitinib, the securin-wild type cancer cells were more resistant to apoptotic induction than the securin-null cancer cells. Surprisingly, both the securin-wild type and securin-null cancer cells expressed the EGFR protein at similar levels. Treatment with gefitinib induced mitochondrial dysfunction, cytochrome c release, caspase-3 activation and poly (ADP-ribose) polymerase protein cleavage, indicating that apoptosis occurred in these cancer cells. The transfection of a GPF-securin expression vector increased both the proliferation rates and resistance to gefitinib-induced death in these cancer cells. Taken together, these findings demonstrate that the presence of securin promotes resistance to gefitinib-induced apoptosis via an EGFR-independent pathway in human cancer cells. (C) 2013 Elsevier Ireland Ltd. All rights reserved.
METHOD FOR TREATING THE DISLOCATION IN A GAN-CONTAINING SEMICONDUCTOR LAYER
(2013-04-25)
Lee Wei-I
;
Yeh Yen-Hsien
;
Wu Yin-Hao
;
Yu Tzu-Yi
A method for treating the threading dislocation within a GaN-containing semiconductor layer is provided. The method includes a substrate is provided. A GaN-containing semiconductor layer with the threading dislocation is formed on the substrate. An etching process with an etching gas is performed to remove the threading dislocation in the GaN-containing semiconductor layer so as to increase the efficiency for the light emitting device.
INDEPENDENTY-CONTROLLED-GATE SRAM
(2013-04-25)
CHUANG Ching-Te
;
Chen Yin-Nien
;
Hsieh Chien-Yu
;
Fan Ming-Long
;
Hu Pi-Ho
The present invention provides an IG 7T FinFET SRAM, which adopts independently-controlled-gate super-high-VT FinFETs to achieve a stacking-like property, whereby to eliminate the read disturb and half-select disturb. Further, the present invention uses keeper circuits and read control voltage to reduce leakage current of the bit lines during read. Furthermore, the present invention can effectively overcome the problem of the conventional 6T SRAM that is likely to have read errors at low operation voltage.
Polarization and Droplet Size Effects in the Laser-Trapping-Induced Reconfiguration in Individual Nematic Liquid Crystal Microdroplets
(2013-04-25)
Usman, Anwar
;
Chiang, Wei-Yi
;
Uwada, Takayuki
;
Masuhara, Hiroshi
;
應用化學系
We experimentally demonstrate reordering throughout the inside of an individual bipolar nematic liquid-crystalline microdroplet optically trapped by a highly focused laser beam, when the laser powers are above a definite threshold. The threshold depends on the droplet size and laser polarization. A physical interpretation of the results is presented by considering the nonlocal orientations of the nematic liquid-crystal molecules in the droplets with the dimensions on the order of the focal spot diameter or larger. On the basis of the finite size approximation, we show that the dependence of threshold power on the droplet size is calculated to be in qualitative agreement with the experimental data.
Magnetic Resonance Imaging of Mouse Islet Grafts Labeled with Novel Chitosan-Coated Superparamagnetic Iron Oxide Nanoparticles
(2013-04-29)
Juang, Jyuhn-Huarng
;
Shen, Chia-Rui
;
Wang, Jiun-Jie
;
Kuo, Chien-Hung
;
Chien, Yu-Wen
Object: To better understand the fate of islet isografts and allografts, we utilized a magnetic resonance (MR) imaging technique to monitor mouse islets labeled with a novel MR contrast agent, chitosan-coated superparamagnetic iron oxide (CSPIO) nanoparticles. Materials and Methods: After being incubated with and without CSPIO (10 mu g/ml), C57BL/6 mouse islets were examined under transmission electron microscope (TEM) and their insulin secretion was measured. Cytotoxicity was examined in alpha (alpha TC1) and beta (NIT-1 and beta TC) cell lines as well as islets. C57BL/6 mice were used as donors and inbred C57BL/6 and Balb/c mice were used as recipients of islet transplantation. Three hundred islets were transplanted under the left kidney capsule of each mouse and then MR was performed in the recipients periodically. At the end of study, the islet graft was removed for histology and TEM studies. Results: After incubation of mouse islets with CSPIO (10 mu g/mL), TEM showed CSPIO in endocytotic vesicles of alpha- and beta-cells at 8 h. Incubation with CSPIO did not affect insulin secretion from islets and death rates of alpha TC1, NIT-1 and beta TC cell lines as well as islets. After syngeneic and allogeneic transplantation, grafts of CSPIO-labeled islets were visualized on MR scans as persistent hypointense areas. At 8 weeks after syngeneic transplantation and 31 days after allogeneic transplantation, histology of CSPIO-labeled islet grafts showed colocalized insulin and iron staining in the same areas but the size of allografts decreased with time. TEM with elementary iron mapping demonstrated CSPIO distributed in the cytoplasm of islet cells, which maintained intact ultrastructure. Conclusion: Our results indicate that after syngeneic and allogeneic transplantation, islets labeled with CSPIO nanoparticles can be effectively and safely imaged by MR.
Atomic-level quantized reaction of HfOx memristor
(2013-04-29)
Syu, Yong-En
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Chang, Ting-Chang
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Lou, Jyun-Hao
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Tsai, Tsung-Ming
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Chang, Kuan-Chang
In this study, we have observed dynamic switching behaviors in a memristive device. There are only a few atoms in the resistive switching reaction which enables the high-speed resistive switching characteristics, which was analyzed dynamically by real-time analyzing tools. From fundamental conductance considerations, the resistance of the conductive path in HfOx memristor is found to be due to barriers which are atomically incremented during the RESET process. Simultaneously, we have demonstrated the quantized switching phenomena at ultra-cryogenic temperature (4 K), which are attributed to the atomic-level reaction in metallic filament. (C) 2013 AIP Publishing LLC.
Band alignment tuning of InAs quantum dots with a thin AlGaAsSb capping layer
(2013-04-29)
Liao, Yu-An
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Hsu, Wei-Ting
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Huang, Shih-Han
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Chiu, Pei-Chin
;
Chyi, Jen-Inn
We investigate the optical properties of InAs quantum dots (QDs) capped with a thin AlxGa1-xAsSb layer. As evidenced from power-dependent and time-resolved photoluminescence (PL) measurements, the GaAsSb-capped QDs with type-II band alignment can be changed to type-I by adding Al into the GaAsSb capping layer. The evolution of band alignment with the Al content in the AlGaAsSb capping layer has also been confirmed by theoretical calculations based on 8-band k . p model. The PL thermal stability and the room temperature PL efficiency are also improved by AlGaAsSb capping. We demonstrate that using the quaternary AlGaAsSb can take the advantages of GaAsSb capping layer on the InAs QDs while retaining a type-I band alignment for applications in long-wavelength light emitters. (C) 2013 AIP Publishing LLC.
Ion sensor for measuring ion concentration of a solution
(2013-04-30)
Yu Peichen
;
Chen Bing-Mau
;
Chang Chia-Hua
;
Hsu Min-Hsiang
;
Huang Chan-Hung
An ion sensor includes: a conductive base structure including a substrate and an electrode film formed on the substrate; a plurality of ion-sensitive nanorods protruding from the electrode film; and an encapsulant enclosing the conductive base structure, surrounding the ion-sensitive nanorods, and formed with a window for exposing the ion-sensitive nanorods. Each of the ion-sensitive nanorods has a conductive core and an ion-sensitive layer formed on and enclosing the conductive core. The ion-sensitive material exhibits an ion selectivity of absorbing an ion of interest thereon for inducing a surface potential corresponding to concentration of the ion of interest.
尋找臨界點上的同情：2012亞洲思想界上海論壇雜感
(深河出版有限公司, 2013-05-01)
呂怡婷
翻身：抗美援朝時期中國的反美大眾運動與冷戰國民的形成
(深河出版有限公司, 2013-05-01)
任佑卿
;
焦艷
「烏托邦」與「豐富的痛苦」
(深河出版有限公司, 2013-05-01)
姚丹
THE ANALYSIS OF SPEED-REPORTING RATES FROM A CELLULAR NETWORK BASED ON A FINGERPRINT-POSITIONING ALGORITHM
(2013-05-01)
Chen, Chi-Hua
;
Lo, Chi-Chun
;
Lin, Hui-Fei
;
傳播與科技學系
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資訊管理與財務金融系註：原資管所+財金所
The collection of real-time traffic information is an important part of intelligent transportation systems. In particular, cellular floating vehicle data (CFVD) technology has become increasingly widespread, and more and more popular for measuring and forecasting real-time traffic information, based on anonymous sampling of the positions of mobile phones. This study proposes an analytical model to analyse the speed-reporting rates - based on communication behaviour, traffic conditions, and the two consecutive fingerprint-positioning locations from the call arrival and call completion signals of the same call - for a feasibility evaluation of CFVD.
Sealing Bump With Bottom-Up Cu TSV Plating Fabrication in 3-D Integration Scheme
(2013-05-01)
Chiang, Cheng-Hao
;
Kuo, Li-Min
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Hu, Yu-Chen
;
Huang, Wen-Chun
;
Ko, Cheng-Ta
A sealing bump approach for the simplification of the conventional bottom-up copper through-silicon via (TSV) plating process flow is developed to reduce the process steps and increase the throughput without sacrificing the structure integrity and electrical performance. In this approach, TSV and bump formation can be achieved simultaneously through the bottom-up plating. Results from the analysis reveal excellent electrical characteristics and quality examination, which indicate that the proposed approach may be a good candidate for the TSV fabrication in 3-D integration.
Reduction of Equivalent Series Inductor Effect in Delay-Ripple Reshaped Constant On-Time Control for Buck Converter With Multilayer Ceramic Capacitors
(2013-05-01)
Chen, Wei-Chung
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Wang, Ching-Sung
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Su, Yi-Ping
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Lee, Yu-Huei
;
Lin, Chia-Ching
The stability of conventional constant on-time control buck converter is constrained by the time constant, which is the product of the output capacitor and its equivalent series resistance (ESR). Specialty polymer capacitor which is mostly used as output capacitor for such a consideration although it limits the performance of converter. On the other hand, the multilayer ceramic capacitors are widely used in commercial power management ICs due to the advantages of low cost and ESR. However, the stability often confronts with the subharmonic problem caused by small time constant. A differential-zero compensator with the noise margin enhancement (DZC-NME) technique in constant on-time control buck dc-dc converter with output ceramic capacitor is proposed in this paper. Thus, the proposed DZC-NME technique not only eliminates the limit of large time constant but also tolerates the existence of equivalent series inductor (ESL) effect. Experiment results demonstrate small output ripple of 10 mV and high efficiency of 91% when ESR is smaller than 1 m Omega and large interference from ESL effect is 40 mV.
Reduplication of adjectives in Chinese: a default state
(2013-05-01)
Liu, Chen-Sheng Luther
;
外國語文學系
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Department of Foreign Languages and Literatures
Chinese reduplicated adjectives denote a perceptible state realized from the property denoted by the adjectival base. The 'degree' conveyed by reduplicated adjectives is the by-product of state realization and can be interpreted as the positive degree. A gradable adjective denoting a property that is more perceptible to human sense is more amenable to reduplication, and the rhetorical style of parallelism can make the property denoted by adjectives more perceptible. The gradability requirement on adjectives amenable to reduplication results from the perceptibility requirement on the state denoted by reduplicated adjectives. Depending on the means by which the property denoted by their adjectival base is realized as a state, reduplicated adjectives can be divided into two types.
Electrical Characteristics of Al2O3/InSb MOSCAPs and the Effect of Postdeposition Annealing Temperatures
(2013-05-01)
Hai Dang Trinh
;
Lin, Yueh Chin
;
Chang, Edward Yi
;
Lee, Ching-Ting
;
Wang, Shin-Yuan
The characteristics of Al2O3/InSb MOSCAPs processed with different postdeposition annealing (PDA) temperatures are investigated. X-ray photoelectron spectroscopy analysis shows a significant reduction of InSb-oxides after HCl plus trimethyl aluminum treatment and oxide deposition. Multifrequency capacitance-voltage (C-V) characteristics exhibit low-frequency and asymmetrical C-V behaviors, in which capacitance in the InSb conduction band side is lower than in the valence band side. The electrical properties of the MOSCAPs are sensitive to PDA temperature and degraded significantly at PDA temperature > 300 degrees C. This degradation is closely related to the diffusion of In, Sb into Al2O3 as indicated by transmission electron microscopy analyses.
Imaging cells and sub-cellular structures with ultrahigh resolution full-field X-ray microscopy
(2013-05-01)
Chien, C. C.
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Tseng, P. Y.
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Chen, H. H.
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Hua, T. E.
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Chen, S. T.
Our experimental results demonstrate that full-field hard-X-ray microscopy is finally able to investigate the internal structure of cells in tissues. This result was made possible by three main factors: the use of a coherent (synchrotron) source of X-rays, the exploitation of contrast mechanisms based on the real part of the refractive index and the magnification provided by high-resolution Fresnel zone-plate objectives. We specifically obtained high-quality microradiographs of human and mouse cells with 29 nm Rayleigh spatial resolution and verified that tomographic reconstruction could be implemented with a final resolution level suitable for subcellular features. We also demonstrated that a phase retrieval method based on a wave propagation algorithm could yield good subcellular images starting from a series of defocused microradiographs. The concluding discussion compares cellular and subcellular hard-X-ray microradiology with other techniques and evaluates its potential impact on biomedical research. (C) 2012 Elsevier Inc. All rights reserved.
為什麼講這個和為什麼這麼講
(深河出版有限公司, 2013-05-01)
王曉明
Rapid Surface-Wave Dispersion and Plane-Wave Reflection Analyses of Planar Corrugated Surfaces by Asymptotic Corrugations Boundary Conditions Even for Oblique Azimuth Planes
(2013-05-01)
Kehn, Malcolm Ng Mou
;
交大名義發表
;
National Chiao Tung University
The asymptotic corrugations boundary condition (ACBC) is used together with classical theory of vector potentials to analyze planar corrugations. A transcendental characteristic equation is derived, from which the dispersion diagram can be obtained, thereby conveying surface wave passband and stopband properties, even for propagation within oblique azimuth planes as well as both principal TE and TM polarizations. From the formulation, field distributions for the regions within the grooves and above the corrugations can also be generated. When compared with the dispersion graphs obtained from characteristic equations derived by the classical transverse resonance technique (TRT), the newly presented ACBC method provides superior accuracy. Explicit formulas for the complex reflection coefficient (amplitude and phase) for both TE and TM polarized plane-wave incidences are also derived as closed-form analytic functions of all parameters (especially the azimuth phi angle of incidence) using a novel concept of unusual transversely phased plane-waves. These proposed approaches are massively more efficient than full-wave solvers, providing unparalleled speedup of computation by thousands of times. The surface-wave and reflection properties of planar corrugations are thus herein analyzed in a unified, complete, and elegant manner that is also highly efficient but yet accurate. This thorough work is thus a great boost to the continued use of corrugated surfaces as artificial magnetic conductors (AMC), electromagnetic bandgap (EBG) structures, and soft/hard surfaces in all walks of antenna design, especially in terms of speed and accuracy.
Very small photoluminescent gold nanoparticles for multimodality biomedical imaging
(2013-05-01)
Lai, Sheng-Feng
;
Chien, Chia-Chi
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Chen, Wen-Chang
;
Chen, Hsiang-Hsin
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Chen, Yi-Yun
An original synthesis method based on X-ray irradiation produced gold nanoparticles (AuNPs) with two important properties for biomedical research: intense visible photoluminescence and very high accumulation in cancer cells. The nanoparticles, coated with MUA (11-mercaptoundecanoid acid), are very small (1.4 nm diameter); the above two properties are not present for even slightly larger sizes. The small MUA-AuNPs are non-cytotoxic (except for very high concentrations) and do not interfere with cancer cell proliferation. Multimodality imaging using visible light fluorescence and X-ray microscopy is demonstrated by tracing the nanoparticle-loaded tumor cells. (C) 2012 Elsevier Inc. All rights reserved.