Browsing by Issue Date, starting with "2012-02-15"

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Aqueous zymography screening of matrix metalloproteinase activity and inhibition based on colorimetric gold nanoparticles
(2012-02-15)
Chuang, Yao-Chen
;
Huang, Wei-Ting
;
Chiang, Pin-Hsuan
;
Tang, Meng-Che
;
Lin, Chih-Sheng
An optical gold nanoparticles (AuNPs)-based method was fabricated for the rapid detection of matrix metalloproteinase (MMP) activity and screening potential MMP inhibitors without sophisticated instruments. The diagnosis platform was composed of AuNPs, particular MMP substrates and 6-mercapto-1-hexanol (MCH). The functionalized AuNPs were subjected to specific MMP digestion, and the MMP found the substrate on AuNPs, such that the AuNPs lost shelter and MCH increased the attraction force between AuNPs. Consequently, AuNPs aggregation and a color change from red to purple with increasing MMP concentration were observed. The surface plasmon resonance (SPR) of the formed AuNPs allowed for the quantitative detection of MMP activity. A sensitive linear correlation existed between the absorbance and the activity of the MMPs, which ranged from 10 ng/mL to 700 ng/mL in NTTC buffer and plasma samples. The proposed colorimetric method could be accomplished in a homogeneous solution with one-step operation in 30 min and has been successfully applied to the determination of particular MMP activity in plasma samples, in which the results are consistent with substrate zymography. This technology may become a simple platform for parallel screening a number of inhibitors and offer an alternative method to studying the efficiency of inhibitors for suppressing MMP activity. The absorbance ratio at 625 nm and 525 nm (A(625)/A(525)) confirmed the efficiency of the inhibitors as observed in substrate zymography. The IC50 of ONO-4817 and galardin for MMP-1, MMP-2 and MMP-7 determined by the proposed colorimetric method was similar to the results of substrate zymography. Crown Copyright (C) 2011 Published by Elsevier B.V. All rights reserved.
Expert system based parallel multi-1D block matching algorithm with implementation for motion estimation
(2012-02-15)
Lin, Shin-Yeu
;
Su, Chong-Wei
;
Huang, Jung-Shou
;
電控工程研究所
;
Institute of Electrical and Control Engineering
In this paper, we propose an expert-system based parallel multi-1-dimensional block matching algorithm (ESPM-1D-BMA) for motion estimation (ME). Instead of the conventional 2D block matching, we employ the parallel multi-1D blocks matching to improve the computing speed. To improve the ME accuracy, we design a knowledge base and inference engine to determine the true motion vector (MV) from the results of parallel multi-1D blocks matching. To speed up the computing speed further, we present a hardware architecture for implementing the ESPM-1D-BMA. We have demonstrated that the MV estimation accuracy achieved by the proposed ESPM-1D-BMA is much better than the comparing fast block matching algorithms and is close to the 2 dimensional full search block matching algorithm (2D-FSBMA). We also demonstrate that the computing speed of the proposed ESPM-1D-BMA is about two times as fast as the mixed-signal 2D-FSBMA (MS-2D-FSBMA). (C) 2011 Elsevier Ltd. All rights reserved.
Photonic crystal horizontally slotted nanobeam cavity for silicon-based nanolasers
(2012-02-15)
Lu, Tsan-Wen
;
Lin, Pin-Tso
;
Lee, Po-Tsung
;
光電工程學系
;
Department of Photonics
We theoretically propose and investigate a TM-polarized one-dimensional photonic crystal nanocavity with a horizontal SiO2 slot on a suspended silicon nanobeam via the three-dimensional finite-element method. The ultrahigh quality factor and ultrasmall effective mode volume of 1.5 x 10(7) and 0.176 half-wavelength cubic of the horizontally SiO2-slotted nanocavity show strong possibilities for realizing an erbium-doped SiO2 nanolaser. This horizontal SiO2 slot structure can be precisely formed via the sputtering process and further transformed into an air slot via selective wet etching for optical index and biomolecule sensing. (C) 2012 Optical Society of America
Spontaneous subpicosecond pulse formation with pulse repetition rate of 80 GHz in a diode-pumped Nd:SrGdGa3O7 disordered crystal laser
(2012-02-15)
Chen, Y. F.
;
Liang, H. C.
;
Tung, J. C.
;
Su, K. W.
;
Zhang, Y. Y.
We explore the operation of spontaneous mode locking in a diode-pumped Nd:SrGdGa3O7 disordered crystal laser. The first- and second-order autocorrelations are simultaneously performed to evaluate the temporal characteristics. An 80 GHz pulse train with a pulse duration as short as 616 fs is observed. The maximum output power is 415 mW at a pump power of 6.1 W. (C) 2012 Optical Society of America
Surface modification of poly(2-methoxy-5-(2 '-ethyl-hexyloxy)-1,4-phenylene vinylene) (MEH-PPV) by confined photo-catalytic oxidation
(2012-02-15)
Yen, Ying-Chieh
;
Cheng, Chih-Chia
;
Wang, Yeh-Sheng
;
Chu, Yu-Lin
;
Lu, Chu-Hua
In this study, the surface of pi-conjugated polymer, poly(2-methoxy-5(2'-ethyl-hexyloxy)-1,4-phenylene vinylene) (MEH-PPV), was successfully modified with the sulfate anion (SO4-) groups by the confined photo-catalytic oxidation (CPO). After the surface modification, the water contact angle of MEH-PPV is changed from 95.5 degrees to 82.1 degrees without influence on its optical properties (based on the UV and PL spectra), and the water droplet can be absorbed on the modified MEH-PPV surface without sliding even at substrate tilt angles of 90 degrees and 180 degrees. The CPO on the MEH-PPV surface is able to further expand the use of MEH-PPV for applications. In addition, the water transport test indicates that the modified MEH-PPV can be a candidate for transporting water droplet. (C) 2011 Elsevier Inc. All rights reserved.
Generalized synchronization of chaotic systems with different orders by fuzzy logic constant controller (vol 38, pg 2302, 2011)
(2012-02-15)
Li, Shih-Yu
;
Ge, Zheng-Ming
;
機械工程學系
;
Department of Mechanical Engineering
Enhanced performance and reliability of NILC-TFTs using FSG buffer layer
(2012-02-15)
Chen, Chien-Chih
;
Wu, YewChung Sermon
;
Chang, Chih-Pang
;
材料科學與工程學系
;
Department of Materials Science and Engineering
A new manufacturing method for Ni-metal-induced lateral crystallization thin film transistors (NILC-TFTs) using fluorine-silicate-glass (FSG) was proposed. In FSG-TFTs, fluorine ion was implanted into the buffer oxide layer to form FSG before NILC processes. It was found FSG-TFTs exhibit high field-effect mobility, low threshold voltage, low subthreshold slope, high ON/OFF current ratio, low trap state density, low interface trap state density, and good reliability compared with typical NILC-TFTs. (c) 2011 Elsevier B.V. All rights reserved.
Synthesis of fluorene-based hyperbranched polymers for solution-processable blue, green, red, and white light-emitting devices
(2012-02-15)
Shih, Hung-Min
;
Wu, Ren-Chi
;
Shih, Ping-I
;
Wang, Chien-Lung
;
Hsu, Chain-Shu
For the purpose of making hyperbranched polymer (Hb-Ps)-based red, green, blue, and white polymer light-emitting diodes (PLEDs), three Hb-Ps Hb-terfluorene (Hb-TF), Hb-4,7-bis(9,9'-dioctylfluoren-2-yl)-2,1,3-benzothiodiazole (Hb-BFBT), and Hb-4,7-bis[(9,9'-dioctylfluoren-2-yl)-thien-2-yl]-2,1,3-benzothiodiazole (Hb-BFTBT) were synthesized via [2+2+2] polycyclotrimerization of the corresponding diacetylene-functionalized monomers. All the synthesized polymers showed excellent thermal stability with degradation temperature higher than 355 degrees C and glass transition temperatures higher than 50 degrees C. Photoluminance (PL) and electroluminance (EL) spectra of the polymers indicate that Hb-TF, Hb-BFBT, and Hb-BFTBT are blue-green, green, and red emitting materials. Maximum brightness of the double-layer devices of Hb-TF, Hb-BFBT, and Hb-BFTBT with the device configuration of indium tin oxide/poly(3,4-ethylene dioxythiophene):poly(styrene sulfonate)/light-emitting polymer/CsF/Al are 48, 42, and 29 cd/m(2); the maximum luminance efficiency of the devices are 0.01, 0.02, and 0.01 cd/A. By using hostguest doped system, saturated red electrophosphorescent devices with a maximum luminance efficiency of 1.61 cd/A were obtained when Hb-TF was used as a host material doped with Os(fptz)(2)(PPh(2)Me(2))(2) as a guest material. A maximum luminance efficiency of 3.39 cd/A of a red polymer light-emitting device was also reached when Hb-BFTBT was used as the guest in the PFO (Poly(9,9-dioctylfluorene)) host layer. In addition, a series of efficient white devices were, which show low turn-on voltage (3.5 V) with highest luminance efficiency of 4.98 cd/A, maximum brightness of 1185 cd/m(2), and the Commission Internationale de l'Eclairage (CIE) coordinates close to ideal white emission (0.33, 0.33), were prepared by using BFBT as auxiliary dopant. (c) 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 50: 696-710, 2012
Existence of traveling wave solutions for diffusive predator-prey type systems
(2012-02-15)
Hsu, Cheng-Hsiung
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Yang, Chi-Ru
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Yang, Ting-Hui
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Yang, Tzi-Sheng
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應用數學系
In this work we investigate the existence of traveling wave solutions for a class of diffusive predator-prey type systems whose each nonlinear term can be separated as a product of suitable smooth functions satisfying some monotonic conditions. The profile equations for the above system can be reduced as a four-dimensional ODE system, and the traveling wave solutions which connect two different equilibria or the small amplitude traveling wave train solutions are equivalent to the heteroclinic orbits or small amplitude periodic solutions of the reduced system. Applying the methods of Wazewski Theorem, LaSalle's Invariance Principle and Hopf bifurcation theory, we obtain the existence results. Our results can apply to various kinds of ecological models. (C) 2011 Elsevier Inc. All rights reserved.
Constructing a yield model for integrated circuits based on a novel fuzzy variable of clustered defect pattern
(2012-02-15)
Lin, Jun-Shuw
;
工業工程與管理學系
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Department of Industrial Engineering and Management
As the wafer size increases, the clustering phenomenon of defects becomes significant. In addition to clustered defects, various clustering patterns also influence the wafer yield. In fact, the recognition of clustering pattern usually exists fuzziness. However, the wafer yield models in previous studies did not consider the fuzziness of clustering pattern belonging to which shape in recognition. Therefore, the objective of this study is to develop a new fuzzy variable of clustering pattern (FVCP) by using fuzzy logic control, and predict the wafer yield by using back-propagation neural network (BPNN) incorporating ant colony optimization (ACO). The proposed method utilizes defect counts, cluster index (CI), and FVCP as inputs for ACO-BPNN. A simulated study is utilized to demonstrate the effectiveness of the proposed model. (C) 2011 Elsevier Ltd. All rights reserved.
Influence of Cu column under-bump-metallizations on current crowding and Joule heating effects of electromigration in flip-chip solder joints
(2012-02-15)
Liang, Y. C.
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Tsao, W. A.
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Chen, Chih
;
Yao, Da-Jeng
;
Huang, Annie T.
The electromigration behavior of SnAg solder bumps with and without Cu column under-bump-metallizations (UBMs) has been investigated under a current density of 2.16 x 10(4) A/cm(2) at 150 degrees C. Different failure modes were observed for the two types of samples. In those without Cu column UBMs, when SnAg solder bumps that had implemented 2 mu m Ni UBMs were current stressed at 2.16 x 10(4) A/cm(2), open failure occurred in the bump that had an electron flow direction from the chip side to the substrate side. However, in those with Cu column UBMs, cracks formed along the interface of Cu6Sn5 intermetallic compounds and the solder on the substrate side in the Sn-3.0Ag-0.5Cu solder bump that had an electron flow direction from the substrate side to the chip side. A three-dimensional simulation of the current density distribution was performed in order to obtain a better understanding of the current crowding behavior in solder bumps. The current crowding effect was found to account for the void formation on both the chip and the substrate side for the two kinds of solder bumps. One more important finding, as confirmed by infrared microscopy, is that the alleviation of current crowding by Cu column UBMs also helped decrease the Joule heating effect in solder bumps during current stressing. Therefore, the measured failure time for the solder joints with Cu column UBMs appears to be much longer than that of the ones with the 2 mu m Ni UBMs. (C) 2012 American Institute of Physics. [doi:10.1063/1.3682484]
具容忍變異字元線驅動抑制機制之隨機存取記憶體
(2012-02-16)
莊景德
;
林宜緯
;
陳家政
;
石維強
本發明提供一種隨機存取記憶體，其包括複數個字元線驅動器、至少一第一追隨電晶體與第二追隨電晶體。各字元線驅動器有一輸入端以接收一解碼訊號、一電源端以接受一工作電壓、與一驅動端以驅動一字元線。一實施例中，第一追隨電晶體有兩通道端，分別耦接字元線驅動器的驅動端與第二追隨電晶體的一個通道端。其中，第一追隨電晶體的電子特性追隨字元線驅動器中驅動電晶體的電子特性，第二追隨電晶體的電子特性追隨各記憶單元中閘通電晶體的電子特性。
液晶透鏡及其製造方法
(2012-02-16)
廖凌嶢
;
黃乙白
;
林裕閔
;
謝漢萍
本發明係揭露一種液晶透鏡及其製造方法，其包含一第一基板、一第一電極、一第一配向層、一液晶層、一第二配向層、一電場均化層、至少一第二電極、一第三電極及一第二基板。第一電極設於第一基板上，第一配向層設於第一電極上，液晶層設於第一配向層上，第二配向層設於液晶層上，電場均化層設於第二配向層上，第二電極及第三電極設於電場均化層上，且第三電極設於第二電極之間。第二基板則設於第二電極及第三電極上。其中第三電極係配合第二電極產生電場梯度，並藉由電場均化層均勻影響液晶層，使液晶達到快速聚焦的效果。
軟性微系統結構及其製造方法
(2012-02-16)
趙子元
;
梁家瑋
;
鄭裕庭
一種將多晶片/單晶片整合於軟基材上形成軟性微系統結構的製造方法，該方法包含低溫覆晶製程以及晶圓級的半導體製程。在本發明中，晶片係利用低溫覆晶製作出金屬對金屬之連接結構，以使晶片整合於軟性基板上；另外，更利用蝕刻位於軟性基板下之犧牲層，使軟性基板可由操作基板上分離。因此，本發明係使用標準化製程將晶片整合於軟基材上，且不需使用特殊的材料或製程，故具有製程簡單、成本低的優點。
Time-Resolved Spectroscopy of Ultrafast Photoisomerization of Octopus Rhodopsin under Photoexcitation
(2012-02-16)
Yabushita, Atsushi
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Kobayashi, Takayoshi
;
Tsuda, Motoyuki
;
電子物理學系
;
Department of Electrophysics
A primary process in vision is the cis-trans photoisomerization of a chromophore of rhodopsin, called retinal. In the present work, we have performed ultrafast time-resolved spectroscopy of octopus rhodopsin. using a sub-5-fs pulse laser. In comparison with our previous study on bacteriorhodopsin, we found that octopus rhodopsin follows similar dynamics after photoexcitation but with different time constants. Spectrogram analysis showed that a C=N stretching mode appeared directly after photoexcitation. After reaching the conical intersection region at 80 fs, the overlapping hydrogen out-of-plane and in-plane C=C-H modes emerged as distinct peaks at similar to 200 fs, finishing a rapid relaxation along the coordinate related with these modes. The intensities of these peaks and a C=C stretching mode were found to be modulated at a period of similar to 500 fs, reflecting torsional motion around the C=C double bond before thermalization with the distribution of structural variations in the all-trans structure in configuration space.
Deciphering the Preference and Predicting the Viability of Circular Permutations in Proteins
(2012-02-16)
Lo, Wei-Cheng
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Dai, Tian
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Liu, Yen-Yi
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Wang, Li-Fen
;
Hwang, Jenn-Kang
Circular permutation (CP) refers to situations in which the termini of a protein are relocated to other positions in the structure. CP occurs naturally and has been artificially created to study protein function, stability and folding. Recently CP is increasingly applied to engineer enzyme structure and function, and to create bifunctional fusion proteins unachievable by tandem fusion. CP is a complicated and expensive technique. An intrinsic difficulty in its application lies in the fact that not every position in a protein is amenable for creating a viable permutant. To examine the preferences of CP and develop CP viability prediction methods, we carried out comprehensive analyses of the sequence, structural, and dynamical properties of known CP sites using a variety of statistics and simulation methods, such as the bootstrap aggregating, permutation test and molecular dynamics simulations. CP particularly favors Gly, Pro, Asp and Asn. Positions preferred by CP lie within coils, loops, turns, and at residues that are exposed to solvent, weakly hydrogen-bonded, environmentally unpacked, or flexible. Disfavored positions include Cys, bulky hydrophobic residues, and residues located within helices or near the protein's core. These results fostered the development of an effective viable CP site prediction system, which combined four machine learning methods, e. g., artificial neural networks, the support vector machine, a random forest, and a hierarchical feature integration procedure developed in this work. As assessed by using the hydrofolate reductase dataset as the independent evaluation dataset, this prediction system achieved an AUC of 0.9. Large-scale predictions have been performed for nine thousand representative protein structures; several new potential applications of CP were thus identified. Many unreported preferences of CP are revealed in this study. The developed system is the best CP viability prediction method currently available. This work will facilitate the application of CP in research and biotechnology.
燃料電池、具有面穿透導電性之板體及其製作方法
(2012-02-16)
許富明
;
陳仁浩
本發明係揭露一種燃料電池、具有面穿透導電性之板體及其製作方法。其中具有面穿透導電性之板體包含一基板及複數個線狀導體，各線狀導體係鍍覆一層金屬材料，並受一磁場的導引而以垂直於基板表面的方式，設置於基板中。另外，基板係為環氧樹脂，線狀導體為碳纖維，而金屬材料則為鐵、鈷或鎳等磁性材料。
Quenching effects of gold nanoparticles in nanocomposites formed in water-soluble conjugated polymer nanoreactors
(2012-02-17)
Yang, Po-Jen
;
Chu, Hsuan-Chih
;
Lee, Yu-Hsien
;
Kobayashi, Takayoshi
;
Chen, Te-Cheng
In this paper we describe the first example of the in situ synthesis of gold nanoparticles (AuNPs) in the presence of a water-soluble conjugated polyfluorene (NPF) presenting pendent ammonium groups, with the polymer acting as an aqueous surfactant and providing fluorescent nanoreactors. Using this approach, we produced well-dispersed NPF-AuNP nanocomposites without the need for any additional reducing agents. The photoluminescence emission intensity of NPF-AuNP nanocomposite solution was quenched to a greater extent upon increasing the concentration of AuNPs, presumably through energy transfer or electron transfer from the fluorescent polymer to the metal nanoparticles. Through variations in the degrees of protonation and deprotonation of the amino groups of NPF at different values of pH, we found that the extent of quenching of AuNPs in NPF-AuNP nanocomposite solutions was directly related to the adsorption and desorption behavior of NPF on the metal surfaces. Transmission electron microscopy revealed that the greatest aggregation of AuNPs in the nanocomposite solution occurred at pH 3. suggesting that the ammonium groups (RNMe2 at pH 8.5; RNMe2H+ at pH 3) of the polymer side chains adsorbed onto the AuNP surfaces under these conditions. Distinct time-resolved fluorescence signals of the AuNP-quenched NPF polymers at different values of pH confirmed the interactions between these species. (C) 2012 Elsevier Ltd. All rights reserved.
障害乗越え補助装置
(2012-02-17)
鄭璧瑩
;
黄健寶
白色発光蛍光体およびその発光装置
(2012-02-17)
陳登銘
;
張峻魁