Browsing by Issue Date, starting with "2011-02-04"

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More on the Magnus-Derek game
(2011-02-04)
Chen, Li-Jui
;
Lin, Jinn-Jy
;
Shieh, Min-Zheng
;
Tsai, Shi-Chun
;
資訊工程學系
We consider the so called Magnus-Derek game, which is a two-person game played on a round table with n positions. The two players are called Magnus and Derek. Initially there is a token placed at position O. In each round Magnus chooses a positive integer m <= n/2 as the distance of the targeted position from his current position for the token to move, and Derek decides a direction, clockwise or counterclockwise, to move the token. The goal of Magnus is to maximize the total number of positions visited, while Derek's is to minimize this number. If both players play optimally, we prove that Magnus, the maximizer, can achieve his goal in O(n) rounds, which improves a previous result with O(n log n) rounds. Then we consider a modified version of the Magnus-Derek game, where one of the players reveals his moves in advance and the other player plays optimally. In this case we prove that it is NP-hard for Derek to achieve his goal if Magnus reveals his moves in advance. On the other hand, Magnus has an advantage to occupy all positions. We also consider the circumstance that both players play randomly, and we show that the expected time to visit all positions is O(n log n). (c) 2010 Elsevier B.V. All rights reserved.
Multi-lane vehicle detection apparatus
(2011-02-08)
Tzuang
;
Ching-Kuang C.
;
Chang
;
Chi-Ho
A vehicle detection apparatus adopting microwave sensing schemes for performing the multi-lane vehicle detection is provided in the present invention. According to the present invention, the signal-to-noise ratio (SNR) of the detected reflecting wave is varied within an inconsiderable range so that the provided apparatus may exhibit a unique property which is adoptable for the multi-lane vehicle detection and the precision is unachievable by the existing detectors.
Power Factor Enhancement for Few-Layered Graphene Films by Molecular Attachments
(2011-02-10)
Sim, Daohao
;
Liu, Dayong
;
Dong, Xiaochen
;
Xiao, Ni
;
Li, Sean
In this work, we prepared few-layered graphene (FLG) films and investigated their thermoelectric properties. It was found that pristine FLG films showed a low thermopower of similar to 40 mu V/K. We further processed these FLG films by attaching them with 1,1'-azobis(cyanocyclohexane) or 1,3,6,8-pyrenetetrasulfonic acid. The thermopower of FLG films with attached molecules increased to above similar to 180 mu V/K. Such enhancement in the thermopower led to an increase in their power factor by more than 4.5 times. Theoretical investigation indicated that a potential difference can be introduced between the outer layer and inner layer of FLG films upon molecule attachments. Simulation of the thermopower based on Kubo's formula provided qualitative support to our experimental results.
Chemical Capture of Phosphine by a Sol-Gel-Derived Cu/TiO2 Adsorbent - Interaction Mechanisms
(2011-02-10)
Chang, Sue-Min
;
Hsu, Ying-Ya
;
Chan, Ting-Shan
;
環境工程研究所
;
Institute of Environmental Engineering
In this study, a novel sol gel-derived Cu/TiO2 adsorbent has been demonstrated to exhibit exceptional capacities of 40,62, 49.52, and 108.48 mg PH3/g Cu/TiO2 for the oxidative capture of phosphine (PH3) in N-2, air, and humidified air, respectively. We have proposed the oxidative mechanisms for PH3 on the Cu/TiO2 sample on the basis of elemental, chemical state, functional group, and microstructural analysis. Moreover, the influence of O-2 and water vapor on the capture capacity is discussed. The transformation of PH3 followed the sequence of PH2 -> H2P-OH -> HP(OH)(2) -> P(OH)(3) -> HO-P=O -> H3PO4. At the same time, the CuO/Cu(OH)(2) moieties in the TiO2 lattice were reduced to Cu-0. The H2P-OH and HO-P=O are the two stable intermediates, and they occupied the active species to inhibit further chemisorption. Direct oxidation of PH3 or the intermediates with adsorbed O-2 was not efficient. However, the Cu/TiO2 sample catalyzed their interactions via reduction and then oxidation of the Cu-2+ ions. Water vapor acts as a cocatalyst to facilitate the oxidation of the intermediates. The end product, H3PO4, migrated to bound the TiO2 support and free the CuO/Cu(OH)(2) for the following catalytic processes. Although competitive adsorption of water molecules initially retarded the adsorption rate, the high extent of oxidation greatly promoted the capture capacity of the Cu/TiO2 in humidified air.
Nanoscale Correlation between Exciton Dissociation and Carrier Transport in Silole-Containing Cyclopentadithiophene-Based Bulk Heterojunction Films
(2011-02-10)
Huang, Jen-Hsien
;
Teng, Chin-Min
;
Hsiao, Yu-Sheng
;
Yen, Feng-Wen
;
Chen, Peilin
Understanding the effects of conjugated polymer structures on exciton lifetimes and morphologies within bulk heterojunction (BHJ) films is a necessary step toward the development of better organic solar cells. Studying the impact of a polymer's structure on the optical, morphological, and performance characteristics of a device can lead to advances in the design of new polymers. In this study, we synthesized carbon- and silicon-bridged cyclopentadithiophene- (CPDT-) based polymers and determined their photophysical properties and morphologies by measuring the exciton lifetime distributions in their BHJ films The silicon-bridged CPDT-based polymer/[6,6]-phenyl-C(61)-butyric acid methyl ester (PCBM) BHJ exhibited a higher degree of luminescence quenching, suggesting that thermodynamically favorable mixing on the molecular scale and nanoscale phase separation occurred simultaneously in the blend film. We attribute this favorable morphology to the presence of strong pi-pi stacking in the silicon-bridged CPDT-based polymers. Under AM 1.5 G illumination (100 mA cm(-2)), a device incorporating the silicon-bridged CPDT-based polymer and PCBM (1:2, w/w) gave an overall power conversion efficiency of 3.5% with a short-circuit current of 9.0 mA cm(-2), an open-circuit voltage of 0.72 V, and a fill factor of 53.6%.
Electrochemical Growth of Gold Nanostructures for Surface-Enhanced Raman Scattering
(2011-02-10)
Yang, Yu-Cheng
;
Huang, Ting-Kai
;
Chen, Yu-Liang
;
Mevellec, Jean-Yves
;
Lefrant, Serge
We demonstrate a facile fabrication of gold nanostructures including Au nanoplates (NPs), Au nanothorns (NTs), and Au nanowires (NWs) on indium tin oxide substrates via electrochemical growth. A simple two-electrode electrochemical deposition system was applied for the fabrication process. Dense Au nanostructures were grown directly on an Au seeding layer on the substrate. After 48 h, the Au NPs were 2-5 mu m in width and 150-200 nm in thickness. The Au NTs were 1-3 mu m in height, 300-500 nm in bottom side width, and 20 nm at the apex. The Au NWs were 30-80 nm in diameter and about 20 mu m in length. The entire process was template-free and economical. We investigated the correlation between surface plasmon resonance (SPR) and surface enhanced scattering (SERS) effects of the Au nanostructures with different excitation wavelengths. By using the SPR absorption maxima of the nanostructures as the excitation wavelengths for SERS, the highest SERS enhancements were achieved. SERS effects of the Au NWs were investigated further. We discovered that the length and the density of the Au NWs affected the SERS performance significantly. The result is rationalized by the amount of "hot spot" generated at the crossing of the Au NWs. With the Au NWs, Rhodamine 6G can be detected at a concentration as low as 10(-9) M.
A Novel Single-Composition Trichromatic White-Light Ca(3)Y(GaO)(3)(BO(3))(4):Ce(3+),Mn(2+),Tb(3+) Phosphor for UV-Light Emitting Diodes
(2011-02-10)
Huang, Chien-Hao
;
Chen, Teng-Ming
;
應用化學系
;
Department of Applied Chemistry
A novel single-composition white-emitting phosphor Ca(3)Y(GaO)(3)(BO(3))(4):Ce(3+), Mn(2+),Tb(3+) has been synthesized by a high-temperature solid-state reaction. The spectral overlap between the emission band of Ce(3+) and the excitation band of Mn(2+), which supports the occurrence of the energy transfer from Ce(3+) to Mn(2+), has been studied and demonstrated to be a resonant type via a dipole-quadrupole mechanism. Because there was no spectral overlap between the emission spectra of Ce(3+) and excitation band of Tb(3+) in our study, no energy transfer from Ce(3+) to Tb(3+) was observed, Indicating that Ce(3+) and Tb(3+) were coexcited. Through effective resonance-type energy transfer and coexcitation, the chromaticity coordinates of Ca(3)Y(GaO)(3)(BO(3))(4):Ce(3+),Mn(2+),Tb(3+) phosphors can be tuned from (0.152, 0.061) for Ca(3)Y-(GaO)(3)(BO(3))(4):Ce(3+) to (0.562, 0.408) for Ca(3)Y(GaO)(3)(BO(3))(4):Mn(2+), and eventually reaching (0.314, 0.573) for Ca(3)Y(GaO)(3)(BO(3))(4):Tb(3+). A white light-emitting diode (LED) was fabricated by using the white-emitting single-composition (Ca(0.97))(3)(Y(0.92))(GaO)(3)(BO(3))(4):0.01Ce(3+),-0.03Mn(2+),0.07Tb(3+) pumped by a 365 nm UV-chip. Our results indicated that the CIE chromaticity coordinates and correlated color temperature (CCT) for white UV-LEDs were (0.31, 0.33) and 6524 K, respectively. Therefore, our novel white Ca(3)Y(GaO)(3)(BO(3))(4):Ce(3+),Mn(2+),Tb(3+) can serve as a key material for phosphor-converted white-light UV-LEDs.
A High-Pressure Infrared Spectroscopic Study on the Interaction of Ionic Liquids with PEO-PPO-PEO Block Copolymers and 1,4-Dioxane
(2011-02-10)
Jiang, Jyh-Chiang
;
Li, Sz-Chi
;
Shih, Pao-Ming
;
Hung, Tzu-Chieh
;
Chang, Shu-Chieh
We have investigated the effect of pressure on imidazolium C-H-O interactions in 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)amide (EMI(+)TFSA(-))/L64 and EMI(+)TFSA(-)/1,4-dioxane mixtures. The addition of Pluronic L64 to EMI(+)TESA(-) leads to appreciable changes in band frequencies and shapes of the imidazolium C-H stretching bands. A possible explanation is the formation of C-H-O interactions between imidazolium C-H groups and oxygen atoms of polyethylene oxides (PEOs). In other words, L64 can be added to change the relative contribution of the isolated and associated components of EMI(+)TESA(-). In contrast to L64, the oxygen atoms of 1,4-dioxane cannot perturb the local structures of imidazolium C-H groups of EMI(+)TFSA(-) and the association configuration is still favored in the presence of 1,4-dioxane. As the pressure is elevated, 1,4-dioxane molecules tend to associate with themselves and TFSA-interacts with EMI(+) to form associated configurations. Our results suggest the formation of association between EMI(+) cation and L64 and the complexes are stable up to the pressure of 2.5 GPa.
Chemical Capture of Phosphine by a Sol-Gel-Derived Cu/TiO(2) Adsorbent - Interaction Mechanisms
(2011-02-10)
Chang, Sue-Min
;
Hsu, Ying-Ya
;
Chan, Ting-Shan
;
環境工程研究所
;
Institute of Environmental Engineering
In this study, a novel sol gel-derived Cu/TiO(2) adsorbent has been demonstrated to exhibit exceptional capacities of 40,62, 49.52, and 108.48 mg PH(3)/g Cu/TiO(2) for the oxidative capture of phosphine (PH(3)) in N(2), air, and humidified air, respectively. We have proposed the oxidative mechanisms for PH(3) on the Cu/TiO(2) sample on the basis of elemental, chemical state, functional group, and microstructural analysis. Moreover, the influence of O(2) and water vapor on the capture capacity is discussed. The transformation of PH(3) followed the sequence of PH(2) -> H(2)P-OH -> HP(OH)(2) -> P(OH)(3) -> HO-P=O -> H(3)PO(4). At the same time, the CuO/Cu(OH)(2) moieties in the TiO(2) lattice were reduced to Cu(0). The H(2)P-OH and HO-P=O are the two stable intermediates, and they occupied the active species to inhibit further chemisorption. Direct oxidation of PH(3) or the intermediates with adsorbed O(2) was not efficient. However, the Cu/TiO(2) sample catalyzed their interactions via reduction and then oxidation of the Cu(2)+ ions. Water vapor acts as a cocatalyst to facilitate the oxidation of the intermediates. The end product, H(3)PO(4), migrated to bound the TiO(2) support and free the CuO/Cu(OH)(2) for the following catalytic processes. Although competitive adsorption of water molecules initially retarded the adsorption rate, the high extent of oxidation greatly promoted the capture capacity of the Cu/TiO(2) in humidified air.
Monitoring and estimating the flow conditions and fish presence probability under various flow conditions at reach scale using genetic algorithms and kriging methods
(2011-02-10)
Lin, Yu-Pin
;
Wang, Cheng-Long
;
Yu, Hsiao-Hsuan
;
Huang, Chung-Wei
;
Wang, Yung-Chieh
The combination of current velocity and water depth influences stream flow conditions, and fish activities prefer particular flow conditions. This study develops a novel optimal flow classification method for identifying types of stream flow based on the current velocity and the water depth using a genetic algorithm. It is applied to the Datuan stream in northern Taiwan. Fish were sampled and their habitat investigated at the study site during the spring, summer, fall and winter of 2008-2009. The current velocity, water depth and maps of the presence probability of fish were estimated by ordinary and indicator kriging. The optimal classification results were compared with the classification results obtained using the Froude number and empirical methods. The flow classification results demonstrate that the proposed optimal flow classification method that considers depth-velocity and optimally identified criteria for classifying flow types, yields a current velocity and water depth of 0.32 (m/s) and 0.29 (m), respectively, and classifies the flow conditions in the study area as pool, run, riffle and slack The variography results of the current velocity and the water depth data reveal that seasonal flows are not spatially stationary among seasons in the study area. Kriging methods and a two-dimensional hydrodynamic model (River 2D) with empirical and optimal flow classification methods are more effective than the Froude number method in classifying flow conditions in the study area. The flow condition classifications and probability maps were generated by River 2D, ordinary kriging and indicator kriging, to quantify the flow conditions preferred by Sicyopterus japonicus in the study area. However, the proposed optimal classification method with kriging and River 2D is an effective alternative method for mapping flow conditions and determining the relationship between flow and the presence probability of target fish in support of stream restoration. (C) 2010 Elsevier B.V. All rights reserved.
A Novel Single-Composition Trichromatic White-Light Ca3Y(GaO)(3)(BO3)(4):Ce3+,Mn2+,Tb3+ Phosphor for UV-Light Emitting Diodes
(2011-02-10)
Huang, Chien-Hao
;
Chen, Teng-Ming
;
應用化學系
;
Department of Applied Chemistry
A novel single-composition white-emitting phosphor Ca3Y(GaO)(3)(BO3)(4):Ce3+, Mn2+,Tb3+ has been synthesized by a high-temperature solid-state reaction. The spectral overlap between the emission band of Ce3+ and the excitation band of Mn2+, which supports the occurrence of the energy transfer from Ce3+ to Mn2+, has been studied and demonstrated to be a resonant type via a dipole-quadrupole mechanism. Because there was no spectral overlap between the emission spectra of Ce3+ and excitation band of Tb3+ in our study, no energy transfer from Ce3+ to Tb3+ was observed, Indicating that Ce3+ and Tb3+ were coexcited. Through effective resonance-type energy transfer and coexcitation, the chromaticity coordinates of Ca3Y(GaO)(3)(BO3)(4):Ce3+,Mn2+,Tb3+ phosphors can be tuned from (0.152, 0.061) for Ca3Y-(GaO)(3)(BO3)(4):Ce3+ to (0.562, 0.408) for Ca3Y(GaO)(3)(BO3)(4):Mn2+, and eventually reaching (0.314, 0.573) for Ca3Y(GaO)(3)(BO3)(4):Tb3+. A white light-emitting diode (LED) was fabricated by using the white-emitting single-composition (Ca-0.97)(3)(Y-0.92)(GaO)(3)(BO3)(4):0.01Ce(3+),-0.03Mn(2+),0.07Tb(3+) pumped by a 365 nm UV-chip. Our results indicated that the CIE chromaticity coordinates and correlated color temperature (CCT) for white UV-LEDs were (0.31, 0.33) and 6524 K, respectively. Therefore, our novel white Ca3Y(GaO)(3)(BO3)(4):Ce3+,Mn2+,Tb3+ can serve as a key material for phosphor-converted white-light UV-LEDs.
應用於生物晶片之電源控制裝置及其操作方法
(2011-02-11)
吳重雨
;
林伯剛
;
林俐如
;
楊文嘉
;
萬諶
本發明揭露一種應用於一生物晶片之電源控制裝置。該生物晶片包含M個區域且每一區域各自包含複數個生物細胞。該電源控制裝置包含一時脈產生模組、一組合式電路及M個控制模組。該時脈產生模組用以產生一時脈訊號。該組合式電路用以根據該時脈訊號產生M個具有不同相位之控制訊號。該M個控制模組中之一第i控制模組係根據第i控制訊號控制第i區域之一電源開啟或關閉。當該第i區域之該電源被開啟，該第i區域中之該等生物細胞被觸發。該等生物細胞具有一觸發－還原時間；該第i區域之該電源所對應之一開啟時間間隔小於該觸發－還原時間。
Implantation of Post-translational Tyrosylprotein Sulfation into a Prokaryotic Expression System
(2011-02-11)
Lu, Lu-Yi
;
Chen, Bo-Han
;
Wu, Jennifer Yun-Shin
;
Wang, Chen-Chu
;
Chen, Da-Huang
A master equation approach to the dynamics of zero electron kinetic energy (ZEKE) states and ZEKE spectroscopy
(2011-02-14)
Wang, Yi-Hsieh
;
Mineo, H.
;
Chao, S. D.
;
Selzle, H. L.
;
Neusser, H. J.
We have theoretically studied important dynamic processes involved in zero electron kinetic energy (ZEKE) spectroscopy using the density matrix method with the inverse Born-Oppenheimer approximation basis sets. In ZEKE spectroscopy, the ZEKE Rydberg states are populated by laser excitation (either a one- or two- photon process), which is followed by autoionizations and l-mixing due to a stray field. The discrimination field is then applied to ionize loosely bound electrons in the ZEKE states. This is followed by using the extraction field to extract electrons from the ZEKE levels which have a strength comparable to that of the extraction field. These extracted electrons are measured for the relative intensities of the ion states under investigation. The spectral positions are determined by the applied laser wavelength and modified by the extraction electric field. In this paper, all of these processes are conducted within the context of the density matrix method. The density matrix method can provide not only the dynamics of system's population and coherence (or phase) but also the rate constants of the processes involved in the ZEKE spectroscopy. Numerical examples are given to demonstrate the theoretical treatments. (C) 2011 American Institute of Physics. [doi: 10.1063/1.3547363]
Beamlike photon-pair generation for two-photon interference and polarization entanglement
(2011-02-14)
Lo, Hsin-Pin
;
Yabushita, Atsushi
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Luo, Chih-Wei
;
Chen, Pochung
;
Kobayashi, Takayoshi
Beamlike photon pairs were generated by spontaneous parametric down-conversion using a type-II beta-BaB2O4 crystal. A pump laser generated photon pairs when it transmitted through the crystal and was reflected back into the crystal by a mirror to generate more photon pairs. The photon pairs generated when the pump laser first transmitted through the crystal (first photon pairs) were also reflected back into the crystal to overlap with the light path of the photon pairs generated in the second transmission of the pump laser through the crystal (second photon pairs). We observed interference between the first and second photon pairs modulated with a half period of the wavelength of the photon pairs, which demonstrates two-photon interference using the beamlike photon pairs. The fringe period confirms that the observed interference is not classical interference but quantum two-photon interference. Through rotating the angles of quarter-wave plates in the light paths of the photon pairs, we generated beamlike photon pairs with entangled polarization. The phase between the first and second photon pairs could be tuned by changing the position of mirrors reflecting the pump pulses and photon pairs. The fringes of coincidence counts showed that the beamlike photon pairs have polarization entanglement.
Balanced carrier transport in organic solar cells employing embedded indium-tin-oxide nanoelectrodes
(2011-02-14)
Hsu, Min-Hsiang
;
Yu, Peichen
;
Huang, Jen-Hsien
;
Chang, Chia-Hua
;
Wu, Chien-Wei
In this paper, we present evidence of balanced electron and hole transport in polymer-fullerene based solar cells by means of embedded indium-tin-oxide nanoelectrodes. Enabled by a controllable electrochemical deposition, the individual nanoelectrodes are uniformly enclosed by a poly (3,4-ethylenedioxythiophene) hole-conducting layer, allowing a relatively short route for holes to reach the anode and hence increasing the effective hole mobility. Consequently, the power conversion efficiency and photogenerated current are maximized with a deposition condition of 50 mu C, where the ratio of the electron to hole mobility is nearly unity. (C) 2011 American Institute of Physics. [doi:10.1063/1.3556565]
Etching method for nitride semiconductor
(2011-02-15)
Lee
;
Wei-I
;
Huang
;
Hsin-Hsiung
;
Zeng
The invention discloses etching method for the nitride semiconductor. Firstly dielectric layer is formed on gallium nitride. The line pattern or dot pattern is formed on the dielectric layer by using the exposure, development, and etching processes. The dielectric layer is used as the mask for the epitaxial lateral overgrowth of follow-up gallium nitride layer. The thick gallium nitride film is grown on the dielectric layer. Then the wet etching process is used to remove the dielectric layer, and the thick gallium nitride film on the dielectric layer is etched to form the specific shape as required.
Predicting and analyzing DNA-binding domains using a systematic approach to identifying a set of informative physicochemical and biochemical properties
(2011-02-15)
Huang, Hui-Lin
;
Lin, I-Che
;
Liou, Yi-Fan
;
Tsai, Chia-Ta
;
Hsu, Kai-Ti
Background: Existing methods of predicting DNA-binding proteins used valuable features of physicochemical properties to design support vector machine (SVM) based classifiers. Generally, selection of physicochemical properties and determination of their corresponding feature vectors rely mainly on known properties of binding mechanism and experience of designers. However, there exists a troublesome problem for designers that some different physicochemical properties have similar vectors of representing 20 amino acids and some closely related physicochemical properties have dissimilar vectors. Results: This study proposes a systematic approach (named Auto-IDPCPs) to automatically identify a set of physicochemical and biochemical properties in the AAindex database to design SVM-based classifiers for predicting and analyzing DNA-binding domains/proteins. Auto-IDPCPs consists of 1) clustering 531 amino acid indices in AAindex into 20 clusters using a fuzzy c-means algorithm, 2) utilizing an efficient genetic algorithm based optimization method IBCGA to select an informative feature set of size m to represent sequences, and 3) analyzing the selected features to identify related physicochemical properties which may affect the binding mechanism of DNA-binding domains/proteins. The proposed Auto-IDPCPs identified m=22 features of properties belonging to five clusters for predicting DNA-binding domains with a five-fold cross-validation accuracy of 87.12%, which is promising compared with the accuracy of 86.62% of the existing method PSSM-400. For predicting DNA-binding sequences, the accuracy of 75.50% was obtained using m=28 features, where PSSM-400 has an accuracy of 74.22%. Auto-IDPCPs and PSSM-400 have accuracies of 80.73% and 82.81%, respectively, applied to an independent test data set of DNA-binding domains. Some typical physicochemical properties discovered are hydrophobicity, secondary structure, charge, solvent accessibility, polarity, flexibility, normalized Van Der Waals volume, pK (pK-C, pK-N, pK-COOH and pK-a(RCOOH)), etc. Conclusions: The proposed approach Auto-IDPCPs would help designers to investigate informative physicochemical and biochemical properties by considering both prediction accuracy and analysis of binding mechanism simultaneously. The approach Auto-IDPCPs can be also applicable to predict and analyze other protein functions from sequences.
Immunopathogenic behaviors of canine transmissible venereal tumor in dogs following an immunotherapy using dendritic/tumor cell hybrid
(2011-02-15)
Pai, Chien-Chun
;
Kuo, Tzong-Fu
;
Mao, Simon J. T.
;
Chuang, Tien-Fu
;
Lin, Chen-Si
Canine transmissible venereal tumor (CTVT) is a naturally occurring tumor that can be transmitted between dogs via live tumor cell inoculation. It is also a spontaneous self-regression tumor and its behavior is closely related to host immune responses. Since CTVT had been widely used for tumor models in canine cancers, whether this self-regression may overtake the immunity elicited from an exogenous tumor vaccine remains unclear and certainly worthwhile to be investigated. In this study, we used DCs/tumor hybrids as a tumor vaccine to evaluate the CTVT model. We prepared mature allogeneic dendritic cells from bone marrow and then assessed their phenotype (CD80, CD83, CD86, CD1a, CD11c, CD40 and MHC II), antigen uptake and presenting abilities. Fused dendritic cell/CTVT hybrids were then used as a vaccine, administered three times at two-week intervals via subcutaneous injection near the bilateral auxiliary and inguinal lymph nodes. In comparison with unvaccinated dogs (spontaneous regressed group), within a period of 2.5 months, the vaccinations substantially inhibited tumor progression (p<0.05) and accelerated the rate of regression by a mechanism involving amplification of the host tumor-specific adaptive immune responses and NK cytotoxicity (p<0.001). Pathologic examination revealed early massive lymphocyte infiltration resulting in final tumor necrosis. In addition, there are not any detectable effects on routine physical, body temperature or blood chemistry examinations. In conclusion, our data furnishes a reference value showing that CTVT is a model of potential use for the study of immunity elicited by vaccines against tumors, and also enable early-phase evaluation of the dendritic cell/tumor vaccine in terms of raising host immunity. (C) 2010 Elsevier B.V. All rights reserved.
iGEMDOCK: a graphical environment of enhancing GEMDOCK using pharmacological interactions and post-screening analysis
(2011-02-15)
Hsu, Kai-Cheng
;
Chen, Yen-Fu
;
Lin, Shen-Rong
;
Yang, Jinn-Moon
;
生物科技學系
Background: Pharmacological interactions are useful for understanding ligand binding mechanisms of a therapeutic target. These interactions are often inferred from a set of active compounds that were acquired experimentally. Moreover, most docking programs loosely coupled the stages (binding-site and ligand preparations, virtual screening, and post-screening analysis) of structure-based virtual screening (VS). An integrated VS environment, which provides the friendly interface to seamlessly combine these VS stages and to identify the pharmacological interactions directly from screening compounds, is valuable for drug discovery. Results: We developed an easy-to-use graphic environment, iGEMDOCK, integrating VS stages (from preparations to post-screening analysis). For post-screening analysis, iGEMDOCK provides biological insights by deriving the pharmacological interactions from screening compounds without relying on the experimental data of active compounds. The pharmacological interactions represent conserved interacting residues, which often form binding pockets with specific physico-chemical properties, to play the essential functions of a target protein. Our experimental results show that the pharmacological interactions derived by iGEMDOCK are often hot spots involving in the biological functions. In addition, iGEMDOCK provides the visualizations of the protein-compound interaction profiles and the hierarchical clustering dendrogram of the compounds for post-screening analysis. Conclusions: We have developed iGEMDOCK to facilitate steps from preparations of target proteins and ligand libraries toward post-screening analysis. iGEMDOCK is especially useful for post-screening analysis and inferring pharmacological interactions from screening compounds. We believe that iGEMDOCK is useful for understanding the ligand binding mechanisms and discovering lead compounds. iGEMDOCK is available at http://gemdock.life.nctu.edu.tw/dock/igemdock.php.