Browsing by Issue Date, starting with "2012-11-19"

Now showing 1 - 20 of 34953

Development of a Gd(III)-Based Receptor-Induced Magnetization Enhancement (RIME) Contrast Agent for beta-Glucuronidase Activity Profiling
(2012-11-19)
Chen, Shih-Hsien
;
Kuo, Yu-Ting
;
Singh, Gyan
;
Cheng, Tian-Lu
;
Su, Yu-Zheng
beta-Glucuronidase is a key lysosomal enzyme and is often overexpressed in necrotic tumor masses. We report here the synthesis of a pro receptor induced magnetization enhancement (pro RIME) magnetic resonance imaging (MRI) contrast agent ([Gd(DOTA-FP beta Gu)]) for molecular imaging of beta-glucuronidase activity in tumor tissues. The contrast agent consists of two parts, a gadolinium complex and a beta-glucuronidase substrate (beta-D-glucopyranuronic acid). The binding association constant (K-A) of [Gd(DOTA-FP beta Gu)] is 7.42 X 10(2), which is significantly lower than that of a commercially available MS-325 (K-A = 3.0 x 10(4)) RIME contrast agent. The low K-A value of [Gd(DOTA-FP beta Gu)] is due to the pendant beta-D-glucopyranuronic acid moiety. Therefore, [Gd(DOTA-FP beta Gu)] can be used for detection of beta-glucuronidase through RIME modulation. The detail mechanism of enzymatic activation of [Gd(DOTA-FP beta Gu)] was elucidated by LC-MS. The kinetics of beta-glucuronidase catalyzed hydrolysis of [Eu(DOTA-FP beta Gu)] at pH 7.4 best fit the Miechalis-Menten kinetic mode with K-m = 1.38 mM, K-cat = 3.76 x 10(3), and k(cat)/K-m = 2.72 x 10(3) M-1 s(-1). The low K-m value indicates high affinity of beta-glucuronidase for [Gd(DOTA-FP beta Gu)] FP beta Gu) at physiological pH. Relaxometric studies revealed that T-1 relaxivity of [Gd(DOTA-FP beta Gu)] changes in response to the concentration of beta-glucuronidase. Consistent with the relaxometric studies, [Gd(DOTA-FP beta Gu)] showed significant change in MR image signal in the presence of beta-glucuronidase and HSA. In vitro and in vivo MR images demonstrated appreciable differences in signal enhancement in the cell lines and tumor xenografts in accordance to their expression levels of beta-glucuronidase. [GRAPHICS] .
Cationic Iridium Complexes with Intramolecular pi-pi Interaction and Enhanced Steric Hindrance for Solid-State Light-Emitting Electrochemical Cells
(2012-11-19)
Chen, Hsiao-Fan
;
Hung, Wen-Yi
;
Chen, Shou-Wei
;
Wang, Ting-Chih
;
Lin, Shih-Wei
Cationic iridium complexes incorporated 4,5-diaza-9,9'-spirobifluorene as N<^>N ancillary ligands, in which one (2) or two (3) phenyl groups were introduced onto 4,5-diazafluorene to afford intraligand pi-pi interactions. The X-ray crystal structures of complexes 2 and 3 show that the pendant phenyl ring forms strong intramolecular face-to-face pi-stacking with the difluorophenyl ring of the cyclometalated ligand with distances of 3.38 angstrom for complex 2 and 3.40 and 3.46 angstrom for complex 3. This pi-pi stacking interaction minimizes the expansion of the metal ligand bonds in the excited state, resulting in a longer device lifetime in the light-emitting electrochemical cell (LEC) devices.
Lithospheric structure of Taiwan from gravity modelling and sequential inversion of seismological and gravity data
(2012-11-20)
Masson, F.
;
Mouyen, M.
;
Hwang, C.
;
Wu, Y. -M.
;
Ponton, F.
Using a Bouguer anomaly map and a dense seismic data set, we have performed two studies in order to improve our knowledge of the deep structure of Taiwan. First, we model the Bouguer anomaly along a profile crossing the island using simple forward modelling. The modelling is 2D, with the hypothesis of cylindrical symmetry. Second we present a joint analysis of gravity anomaly and seismic arrival time data recorded in Taiwan. An initial velocity model has been obtained by local earthquake tomography (LET) of the seismological data. The LET velocity model was used to construct an initial 3D gravity model, using a linear velocity-density relationship (Birch's law). The synthetic Bouguer anomaly calculated for this model has the same shape and wavelength as the observed anomaly. However some characteristics of the anomaly map are not retrieved. To derive a crustal velocity/density model which accounts for both types of observations, we performed a sequential inversion of seismological and gravity data. The variance reduction of the arrival time data for the final sequential model was comparable to the variance reduction obtained by simple LET. Moreover, the sequential model explained about 80% of the observed gravity anomaly. New 3D model of Taiwan lithosphere is presented. (C) 2012 Elsevier B.V. All rights reserved.
Vertical crustal motion of active plate convergence in Taiwan derived from tide gauge, altimetry, and GPS data
(2012-11-20)
Chang, Emmy T. Y.
;
Chao, Benjamin F.
;
Chiang, Chieh-Chung
;
Hwang, Cheinway
;
土木工程學系
Located at the converging junction between the Eurasian and Philippine Sea plates, the island of Taiwan is subject to an active lithospheric deformation as well as seismicity. Taking the difference between the satellite altimetry data (ALT) that give the absolute sea level variation and the tide gauge data (TG) that record the relative sea level variation, we obtain the absolute vertical crustal motion of the tide gauge sites. We use 20 TO stations along the west and east coasts of Taiwan along with the ALT measurements from the TOPEX/Poseidon-Jason satellites in the nearby waters. The ALT-TG results are compared with vertical GPS measurements in discussing vertical motion. We find a general subsidence of the entire Taiwan coast during the past two decades. The west coast sees no prominent vertical motion but with a severe local subsidence due to the over-withdrawal of groundwater. On the east coast, the ALT-TG results in the northern section demonstrate a northward dipping motion. The elastic thickness of the neighboring oceanic lithosphere modeled as an elastic plate with the flexure of the subducting plate shows that the adjacent Philippine Sea plate should be an old, thick oceanic plate, which could drag the slab into the mantle as manifested in a gentle northward subsidence in the northeast Taiwan. In the southern section of the east coast, the ALT-TG results reveal a segmented or undulating pattern in the vertical-motion rates, judging from the different behaviors between the co-seismic and interseismic vertical motions marked by the major earthquakes during the studied period, we postulate a temporal saw-tooth scenario for the deformation in phases. It demonstrates the opposite motions under different mechanisms in the frontal sections of the subduction zone, which can be understood with lateral collision and slab dragging subject to varied temporal and spatial dependences. (C) 2011 Elsevier B.V. All rights reserved.
Real-Time Microscopic Assessment of Ischemia-Reperfusion with Intravital Autofluorescence Imaging
(2012-11-20)
Lu, Hsueh-Han
;
Chang, Wei-Tien
;
Wu, Yao-Ming
;
Liau, Ian
;
應用化學系
交大e-News第130期
(2012-11-20)
Secretariat
;
國立交通大學秘書室
Efficient solid-state white light-emitting electrochemical cells based on phosphorescent sensitization
(2012-11-21)
Su, Hai-Ching
;
Chen, Hsiao-Fan
;
Chen, Po-Hsien
;
Lin, Shih-Wei
;
Liao, Chih-Teng
Efficient phosphorescent sensitized white light-emitting electrochemical cells (LECs) based on a blue-emitting phosphorescent cationic transition metal complex (CTMC) doped with a red-emitting fluorescent dye are demonstrated. Blue phosphorescence and phosphorescence-sensitized red fluorescence contribute to white emission. Furthermore, the microcavity effect of the device structure is utilized to suppress the green part of the electroluminescence (EL) spectrum of the blue-emitting phosphorescent metal complex (1) via destructive interference. Hence, more saturated blue EL emission can be obtained. When combined with saturated red emission, white EL emission with Commission Internationale de l'Eclairage coordinates approaching (0.33, 0.33) can be obtained without the need for saturated deep-blue emitting CTMCs. Peak external quantum efficiency and power efficiency of the phosphorescence sensitized white LECs are up to 7.9% and 15.6 lm W-1, respectively. These efficiencies are among the highest reported for white LECs and reveal that phosphorescent sensitization is useful for improving device efficiencies of white LECs.
Particle chain display - an optofluidic electronic paper
(2012-11-21)
Fan, Shih-Kang
;
Chiu, Cheng-Pu
;
Hsu, Ching-Hsiang
;
Chen, Shih-Chiang
;
Huang, Li-Lin
A particle-based display medium and a driving mechanism insensitive to the charge polarity of those particles, based on the transformation of particle chains, are developed for reflective electronic paper displays. Particle chains are formed by dipole-dipole interactions between polarized particles with an appropriate electric field applied across the tested display medium, L e. the solution that regulates the light in the field of display technology, containing neutral polystyrene (PS) particles dispersed in water. Formation of the particle chains results in a large change in optical transmittance and reflectance of the display medium. The performance of the particle chain displays (PCD) was evaluated according to macroscopic (device), microscopic (particle) and optical (reflectance) points of view. A display medium (thickness 100 mu m) containing colored PS particles (3 mu m, 2.5% w/v) was polarized to display the fixed images of the directly driven electrodes and programmable images of arrayed (5 x 5) electrodes with electric fields (0.48 MV m(-1) and 0.09 MV m(-1), 500 kHz, respectively). The formation of particle chains under electric fields (0.2 MV m(-1) and 0.4 MV m(-1), 500 kHz) was observed in the microscopic images of a display medium (thickness 100 mu m) with fluorescent PS particles (5 mu m, 1%). Images recorded with a confocal microscope demonstrated the particle chains. The opacity, a common parameter serving to characterize a display medium, was derived by measuring the reflectance ratio of a black background to a white background of the display medium with varied thickness and particle concentration. The temporal response of a display medium (thickness 50 mu m) with black PS particles (3 mu m, 5%) was tested. When an electric field (0.6 MV m(-1), 500 kHz) was applied, the reflectance increased twice at the first data point in 0.7 s, attaining a contrast ratio of 2. Application of a voltage (20 s) yielded a contrast ratio of 10. The performance of a tested display medium, composed of simple PS particles and water and driven to form particle chains by polarization, is reported.
一種鈣鈦礦氧化物觸媒的製備方法
(2012-11-21)
吳樸偉
;
張雲閔
本發明係提供一種La0.6Ca0.4Co1-xIrxO3(x=0~1)鈣鈦礦氧化物觸媒的製備方法。該觸媒在鹼性系統中，同時具有優良的氧氣生成與還原反應雙功能催化能力。使用固態燒結法(Solid State Reaction Method)，且以檸檬酸鹽法(Amorphous Citrate Precursor)與機械研磨法(Mechanical Alloying)以製備鈣鈦礦觸媒。此觸媒的電化學活性，相對於傳統La0.6Ca0.4CoO3，不論是電流對電壓曲線、定電流放電或定電流充電，不僅能有效地降低電流對電壓的損失，更能有效地提升電化學性能。
Isotope Label-Aided Mass Spectrometry Reveals the Influence of Environmental Factors on Metabolism in Single Eggs of Fruit Fly
(2012-11-21)
Tseng, Te-Wei
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Wu, June-Tai
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Chen, Yu-Chie
;
Urban, Pawel L.
;
應用化學系
In order to investigate the influence of light/dark cycle on the biosynthesis of metabolites during oogenesis, here we demonstrate a simple experimental protocol which combines in-vivo isotopic labeling of primary metabolites with mass spectrometric analysis of single eggs of fruit fly (Drosophila melanogaster). First, fruit flies were adapted to light/dark cycle using artificial white light. Second, female flies were incubated with an isotopically labeled sugar (C-13(6)-glucose) for 12 h - either during the circadian day or the circadian night, at light or at dark. Third, eggs were obtained from the incubated female flies, and analyzed individually by matrix-assisted laser desorption/ionization (MALDI) mass spectrometry (MS): this yielded information about the extent of labeling with carbon-13. Since the incorporation of carbon-13 to uridine diphosphate glucose (UDP-glucose) in fruit fly eggs is very fast, the labeling of this metabolite was used as an indicator of the biosynthesis of metabolites flies/eggs during 12-h periods, which correspond to circadian day or circadian night. The results reveal that once the flies adapted to the 12-h-light/12-h-dark cycle, the incorporation of carbon-13 to UDP-glucose present in fruit fly eggs was not markedly altered by an acute perturbation to this cycle. This effect may be due to a relationship between biosynthesis of primary metabolites in developing eggs and an alteration to the intake of the labeled substrate - possibly related to the change of the feeding habit. Overall, the study shows the possibility of using MALDI-MS in conjunction with isotopic labeling of small metazoans to unravel the influence of environmental cues on primary metabolism.
於矽晶片上形成太陽能電池之矽鍺層的方法
(2012-11-21)
張翼
;
唐士軒
;
林岳欽
本發明係在矽基板上成長矽鍺層，並在其上成長三五族化合物半導體太陽能電池。首先在矽晶片上使用矽離子佈植方法以促進矽晶片和矽鍺磊晶層的鬆弛，降低矽鍺磊晶層的厚度，再於矽基板上生長無應力的P型摻雜矽鍺緩衝層，藉以降低三五族高效率太陽能電池生產成本。並於矽鍺緩衝層上形成三五族高效率太陽能電池。
Stable Isotope-Labeled Raman Imaging Reveals Dynamic Proteome Localization to Lipid Droplets in Single Fission Yeast Cells
(2012-11-21)
Venkata, Hemanth Nag Noothalapati
;
Shigeto, Shinsuke
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應用化學系
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應用化學系分子科學碩博班
;
Department of Applied Chemistry
Lipid droplets have been hypothesized to be intimately associated with intracellular proteins. However, there is little direct evidence for both spatiotemporal and functional relations between lipid droplets and proteins provided by molecular-level studies on intact cells. Here, we present in vivo time-lapse Raman imaging, coupled with stable-isotope (C-13) labeling, of single living Schizosaccharomyces pombe cells. Using characteristic Raman bands of proteins and lipids, we dynamically visualized the process by which C-13-glucose in the medium was assimilated into those intracellular components. Our results show that the proteins newly synthesized from incorporated C-13-substrate are localized specifically to lipid droplets as the lipid concentration within the cell increases. We demonstrate that the present method offers a unique platform for proteome visualization without the need for tagging individual proteins with fluorescent probes.
Laser-Polarization Effects on Coherent Vibronic Excitation of Molecules with Quasi-Degenerate Electronic States
(2012-11-22)
Kanno, Manabu
;
Ono, Yukari
;
Kono, Hirohiko
;
Fujimura, Yuichi
;
應用化學系分子科學碩博班
The laser-polarization effects on nonadiabatically couple pi-electron rotation (ring current) and molecular vibration have been theoretically analyzed for aromatic molecules with quasi-degenerate excited states irradiated by an ultrashort laser pulse of arbitrary polarization. We first derived general formulations of the coherent electronic wave packet and expectation value of electronic angular momentum within a frozen-nuclei model. The relative quantum phase of the superposed quasi-degenerate States, which.. determines the oscillating behavior of angular momentum; can be manipulated by the ellipticity and orientation of the incident laser. Nuclear wave packet simulations with a model molecule confirmed the controllability of pi-electron rotation, although the angular momentum is gradually reduced by nonadiabatic couplings. The amplitude of molecular vibration depends prominently on the orientation of linear polarization vectors rather than the helicity of circular polarization. The characteristic feature in vibrational amplitudes is attributed to the interference in nonadiabatic transition governed by the-relative quantum phase between nuclear wave packets. This offers a new strategy for laser control of molecular vibrations through the wave packet interference in nonadiabatic transition.
DRUG CARRIER WITH THERMAL SENSITIVITY, MANUFACTURING METHOD THEREOF, AND USE THEREOF
(2012-11-22)
CHEN San-Yuan
;
HU Shang-Hsiu
;
HUANG Hsin-Yang
A drug carrier with thermal sensitivity, a manufacturing method thereof, and a use thereof are disclosed. The drug carrier comprises a nano-magnetic particle, a drug, a composite polymer, and a dense silica shell. The nano-magnetic particle and the drug are encapsulated in the composite polymer which is formed by self-assembly a water-soluble polymer (such as poly vinyl alcohol) and a thermosensitive copolymer (such as Pluronic F68 or Pluronic F127). The stability and drug release of the drug carrier a can be adjusted by combining PVA and thermosensitive copolymer with a different ratio. When an external magnetic field was applied, the cores exhibit significant size shrinkage and the diameter of the drug carrier decreases more than 10 folds due to the change of temperature, which causes burst-like drug release because of shell destruction and physical collapse of the drug carrier.
RUTHENIUM COMPLEX-BASED PHOTOSENSITIZER DYES FOR DYE-SENSITIZED SOLAR CELLS
(2012-11-22)
Diau Eric Wei-Guang
;
Huang Wei-Kai
This invention relates to ruthenium complex-based photosensitizer dyes for dye-sensitized solar cells, which have a general structural formula represented by formula (I).
Vanadium Substitution of LiFePO4 Cathode Materials To Enhance the Capacity of LiFePO4-Based Lithium-Ion Batteries
(2012-11-22)
Chiang, Ching-Yu
;
Su, Hui-Chia
;
Wu, Pin-Jiun
;
Liu, Heng-Jui
;
Hu, Chih-Wei
The mechanism of enhancing the capacity of the LiFePO4 cathodes in lithium ion batteries by the addition of a small amount of vanadium, which locate on the lithium site and induce lithium vacancies in the crystal structure, is reported in this article. As a result, the capacity increases from 138 mAh/g found for pristine LiFePO4 to 155 mAh/g for the V-added compound, and the conductivity increases from 4.75 x 10(-4) S/cm for the LiFePO4 without V addition to 1.9 x 10(-2) S/cm for the V-added compound. A possible model to facilitate the enhancement of conductivity and capacity is described with evidence supported by X-ray powder diffraction, X-ray absorption spectroscopy, and neutron powder diffraction data.
LOCALIZATION DEVICE AND LOCALIZATION METHOD WITH THE ASSISTANCE OF AUGMENTED REALITY
(2012-11-22)
Lo Chi-Chung
;
Tseng Yu-Chee
;
Lin Chung-Wei
;
Kuo Lun-Chia
;
Lin Tsung-Ching
A localization device assisted with augmented reality and a localization method thereof are provided. The localization device includes a subject object coordinate generating unit, a relative angle determining element and a processing unit. The subject object coordinate generating unit selects at least three subject objects outside the localization device and obtains at least three subject object coordinate values of the at least three subject objects. The relative angle determining element determines at least two viewing angle differences between any two of the at least three subject objects. The processing unit generates a location coordinate value of the localization device according to the at least two viewing angle differences and the at least three subject object coordinate values.
民歌音樂的波瀾
(2012-11-25)
高綮翊
;
Department of Communication and Technology
;
傳播與科技學系
每個年代，都有屬於他們的流行歌，這些旋律，陪伴著那個時代的人成長，體會過年少青狂，經歷過成長蛻變。每一首歌背後，都連結著一個個的故事，值得我們細細品味。
這個人　我的瘋言瘋語
(2012-11-25)
張睿文
;
Department of Communication and Technology
;
傳播與科技學系
無法表達，因為不想讓人知道。當看到的時候，千萬不要看得太認真，因為真假虛實並沒有一定的標準。就當作保有童年的天真和無知的胡言亂語吧！
V怪客的革命魅力
(2012-11-25)
陳儀澧
;
Department of Communication and Technology
;
傳播與科技學系
撇開經過改編之後翻攝的電影會有失原味，導演詹姆斯．麥克特透過整部電影，想向觀眾述說的理念、以及敘事運用的手法操作，可以說是相當的出神入化。