Browsing by Issue Date, starting with "2014-12-08"

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Homopharma: A new concept for exploring the molecular binding mechanisms and drug repurposing
(2014-12-08)
Chiu, Yi-Yuan
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Tseng, Jen-Hu
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Liu, Kuan-Hsiu
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Lin, Chih-Ta
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Hsu, Kai-Cheng
Background: Drugs that simultaneously target multiple proteins often improve efficacy, particularly in the treatment of complex diseases such as cancers and central nervous system disorders. Many approaches have been proposed to identify the potential targets of a drug. Recently, we have introduced Space-Related Pharmamotif (SRPmotif) method to recognize the proteins that share similar binding environments. In addition, compounds with similar topology may bind to similar proteins and have similar protein-compound interactions. However, few studies have focused on exploring the relationships between binding environments and protein-compound interactions, which is important for understanding molecular binding mechanisms and helpful to be used in discovering drug repurposing. Results: In this study, we propose a new concept of "Homopharma", combining similar binding environments and protein-compound interaction profiles, to explore the molecular binding mechanisms and drug repurposing. A Homopharma consists of a set of proteins which have the conserved binding environment and a set of compounds that share similar structures and functional groups. These proteins and compounds present conserved interactions and similar physicochemical properties. Therefore, these compounds are often able to inhibit the proteins in a Homopharma. Our experimental results show that the proteins and compounds in a Homopharma often have similar protein-compound interactions, comprising conserved specific residues and functional sites. Based on the Homopharma concept, we selected four flavonoid derivatives and 32 human protein kinases for enzymatic profiling. Among these 128 bioassays, the IC50 of 56 and 25 flavonoid-kinase inhibitions are less than 10 mu M and 1 mu M, respectively. Furthermore, these experimental results suggest that these flavonoids can be used as anticancer compounds, such as oral and colorectal cancer drugs. Conclusions: The experimental results show that the Homopharma is useful for identifying key binding environments of proteins and compounds and discovering new inhibitory effects. We believe that the Homopharma concept can have the potential for understanding molecular binding mechanisms and providing new clues for drug development.
Lasing behaviors upon phase transition in solution-processed perovskite thin films
(2014-12-08)
Kao, Tsung Sheng
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Chou, Yu-Hsun
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Chou, Chun-Hsien
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Chen, Fang-Chung
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Lu, Tien-Chang
In this paper, the temperature dependent lasing characteristics of solution-processed organic-inorganic halide perovskite CH3NH3PbI3 films have been demonstrated. The lasing temperature can be sustained up to a near room temperature at 260 K. Via the temperature dependent photoluminescence (PL) measurements, an emerged phase-transition band can be observed, ascribing to the crystalline structures changed from the orthorhombic to tetragonal phase states in the perovskites as a function of a gradual increase in the ambient temperature. The optical characteristics of the PL emission peaks and the anomalous shifts of the peak intensities are highly correspondent with the phase states in perovskites at different temperatures, showing a low-threshold lasing behavior at the phase transition. The laser cavities may be formed under multiple random scattering provided by the polycrystalline grain boundary and/or phase separation upon the phase transition. Since the threshold gain is potentially high in the random cavities, the large material gain exhibited by the solution-processed perovskite would be very promising in making practical laser devices. (C) 2014 AIP Publishing LLC.
SCMHBP: prediction and analysis of heme binding proteins using propensity scores of dipeptides
(2014-12-08)
Liou, Yi-Fan
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Charoenkwan, Phasit
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Srinivasulu, Yerukala Sathipati
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Vasylenko, Tamara
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Lai, Shih-Chung
Background: Heme binding proteins (HBPs) are metalloproteins that contain a heme ligand (an iron-porphyrin complex) as the prosthetic group. Several computational methods have been proposed to predict heme binding residues and thereby to understand the interactions between heme and its host proteins. However, few in silico methods for identifying HBPs have been proposed. Results: This work proposes a scoring card method (SCM) based method (named SCMHBP) for predicting and analyzing HBPs from sequences. A balanced dataset of 747 HBPs (selected using a Gene Ontology term GO: 0020037) and 747 non-HBPs (selected from 91,414 putative non-HBPs) with an identity of 25% was firstly established. Consequently, a set of scores that quantified the propensity of amino acids and dipeptides to be HBPs is estimated using SCM to maximize the predictive accuracy of SCMHBP. Finally, the informative physicochemical properties of 20 amino acids are identified by utilizing the estimated propensity scores to be used to categorize HBPs. The training and mean test accuracies of SCMHBP applied to three independent test datasets are 85.90% and 71.57%, respectively. SCMHBP performs well relative to comparison with such methods as support vector machine (SVM), decision tree J48, and Bayes classifiers. The putative non-HBPs with high sequence propensity scores are potential HBPs, which can be further validated by experimental confirmation. The propensity scores of individual amino acids and dipeptides are examined to elucidate the interactions between heme and its host proteins. The following characteristics of HBPs are derived from the propensity scores: 1) aromatic side chains are important to the effectiveness of specific HBP functions; 2) a hydrophobic environment is important in the interaction between heme and binding sites; and 3) the whole HBP has low flexibility whereas the heme binding residues are relatively flexible. Conclusions: SCMHBP yields knowledge that improves our understanding of HBPs rather than merely improves the prediction accuracy in predicting HBPs.
Temperature-dependent carrier-phonon coupling in topological insulator Bi2Se3
(2014-12-08)
Lai, Yi-Ping
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Chen, Hsueh-Ju
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Wu, Kuang-Hsiung
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Liu, Jia-Ming
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電子物理學系
Temperature-dependent (11.0K +/- 294.5 K) carrier-phonon coupling in Bi2Se3 is investigated by ultrafast pump-probe spectroscopy. The rise time of the differential reflectivity is interpreted by a combined effect of electron temperature relaxation and hot-phonon lifetime. The electron-phonon coupling constant of the bulk state (lambda = 0.63 +/- 0.05) is deduced from theoretical fitting. Increasing hot-phonon lifetime with decreasing temperature is attributed to a decreasing phonon-phonon collision rate. A complete analysis of the thermalization process is presented. Understanding carrier and phonon dynamics is essential for future optoelectronic and spintronic applications of topological insulators. (C) 2014 AIP Publishing LLC.
Cooperative spectrum sensing method and system for locationing primary transmitters in a cognitive radio system
(2014-12-09)
Wu Sau-Hsuan
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Huang Din-Hwa
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Ko Chun-Hsien
In a cooperative spectrum sensing method and system for locationing primary transmitters, each of secondary users transmits to a corresponding one of cognitive radio (CR) base station location information thereof and a received signal strength indicator (RSSI) value generated thereby in response to sensing power signals from the primary transmitters. The CR base stations transmit the location information and the RDDI values of the secondary users to a data fusion center such that the data fusion center obtains the number and locations of the primary transmitters based on the location information and the RSSI values received thereby using a learning algorithm to thereby reconstruct a power propagation map of the primary transmitters.
Method for estimating capacitance weight errors and successive approximation analog to digital converter using the same
(2014-12-09)
Hong Hao-Chiao
;
Hsieh Tsung-Yin
A successive approximation (SA) analog-to-digital converter (ADC) capable of estimating its own capacitance weight errors includes a comparator, a capacitor set, a switch set and a controller. The capacitor set includes a primary capacitor array including a plurality of binary-weighted capacitors, and a secondary capacitor array including a plurality of binary-weighted capacitors with known capacitance weights. The controller controls the switch set and repeats the steps of pre-charging the primary capacitor array, redistributing electric charges to the primary capacitor array and the secondary capacitor array, and performing a successive approximation binary searching on the primary capacitor array and the secondary capacitor array to calculate the capacitance weight error of each capacitor in the primary capacitor array. The calculated capacitance weight errors are used for calibrating the output of the successive approximation ADC.
Method of semiconductor manufacturing process
(2014-12-09)
Wu YewChung Sermon
;
Wang Bau-Ming
;
Hsiao Feng-Ching
The present invention related to a method for manufacturing a semiconductor, comprising steps of: providing a growing substrate; forming a semiconductor substrate on the growing substrate; forming a first structure with plural grooves and between the growing substrate and the semiconductor substrate; and changing the temperature of the growing substrate and the semiconductor substrate.
Microphone array structure able to reduce noise and improve speech quality and method thereof
(2014-12-09)
Bai Mingsian R.
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Chen Chun-Hung
The present invention discloses a microphone array structure able to reduce noise and improve speech quality and a method thereof. The method of the present invention comprises steps: using at least two microphone to receive at least two microphone signals each containing a noise signal and a speech signal; using FFT modules to transform the microphone signals into frequency-domain signals; calculating an included angle between a speech signal and a noise signal of the microphone signal, and selecting a phase difference estimation algorithm, a noise reduction algorithm or both to reduce noise according to the included angle; if the phase difference estimation algorithm is used, calculating phase difference of the microphone signals to obtain a time-space domain mask signal; and multiplying the mask signal and the average of the microphone signals to obtain the speech signals of the microphone signals. Thereby is eliminated noise and improve speech quality.
Method for visualizing a complicated metro map in a limited displaying area
(2014-12-09)
Wang Yu-Shuen
;
Chi Ming-Te
The prevented invention provides a method to visualize complicated metro maps in a limited displaying area, in which the route to the passenger's destination is highlighted. In order to achieve high readability, it sets 1) the distance between neighboring stations to be equal, 2) the transportation lines to lie in octilinear directions, 3) the angles of incident edges at each station to be maximized, and 4) the station positions to be inside the displaying area. It also labels the names of stations that passenger will pass by to make the route navigation easy and intuitive.
開幕講座
(2014-12-10)
Library
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圖書館
快分享啦!；講座：用iPad彩繪夢想怪獸老爸-黃世明 12/10(三)12:10-13:10 圖書館2樓大廳；免報名+免費參加+供餐點講座；網路圖文作家，怪獸老爸，著有「帶著iPad玩畫畫!塗鴉創意50招」等書。 12/10，對於圖文創作有興趣的同學，千萬別錯過了!
好刊大放送
(2014-12-11)
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好刊大放送喜歡就帶走
Efficient Optical Trapping of CdTe Quantum Dots by Femtosecond Laser Pulses
(2014-12-11)
Chiang, Wei-Yi
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Okuhata, Tomoki
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Usman, Anwar
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Tamai, Naoto
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Masuhara, Hiroshi
The development in optical trapping and manipulation has been showing rapid progress, most of it is in the small particle sizes in nanometer scales, substituting the conventional continuous-wave lasers with high-repetition-rate ultrashort laser pulse train and nonlinear optical effects. Here, we evaluate two-photon absorption in optical trapping of 2.7 nm-sized CdTe quantum dots (QDs) with high-repetition-rate femtosecond pulse train by probing laser intensity dependence of both Rayleigh scattering image and the two-photon-induced luminescence spectrum of the optically trapped QDs. The Rayleigh scattering imaging indicates that the two-photon absorption (TPA) process enhances trapping ability of the QDs. Similarly, a nonlinear increase of the two-photon-induced luminescence with the incident laser intensity fairly indicates the existence of the TPA process.
具有由資料控制之電源供應的靜態隨機存取記憶體
(2014-12-11)
莊景德
;
楊皓義
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夏茂墀
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林勇維
;
盧建宇
Characterizing the electrical properties of raised S/D junctionless thin-film transistors with a dual-gate structure
(2014-12-11)
Cheng, Ya-Chi
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Chen, Hung-Bin
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Su, Jun-Ji
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Shao, Chi-Shen
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Wang, Cheng-Ping
This letter demonstrates a p-type raised source-and-drain (raised S/D) junctionless thin-film transistors (JL-TFTs) with a dual-gate structure. The raised S/D structure provides a high saturation current (> 1 mu A/mu m). The subthreshold swing (SS) is 100 mV/decade and the drain-induced barrier lowering (DIBL) is 0.8 mV/V, and the I-on/I-off current ratio is over 10(8) A/A for L-g = 1 mu m. Using a thin channel structure obtains excellent performance in the raised S/D structure. Besides the basic electrical characteristics, the dual-gate structure can also be used to adjust V-th in multi-V-th circuit designs. This study examines the feasibility of using JL-TFTs in future three-dimensional (3D) layer-to-layer stacked high-density device applications.
SYSTEM ARCHITECTURE AND METHOD FOR SERVICE CONTINUITY IN HETEROGENEOUS WIRELESS NETWORK
(2014-12-11)
TSENG CHIEN-CHAO
;
CHAN MIN-CHENG
The present invention provides a system architecture and a method for service continuity in heterogeneous wireless networks, which comprises a handover decision module and a session continuity module. The handover decision module is responsible for maintaining link layer association and network layer reachability in according to the underlying network conditions to fulfill the service requirement of applications. When acting as a sender, the session continuity module will select transmission path(s), reestablish the transport connection(s) and tag packets with session IDs and sequence numbers. When acting as a receiver, the session continuity module will identify and reorder packets using session IDs and sequence numbers, regardless of the IP addresses and ports of the packets. To sum up, the present invention can provide service continuity and multipath transmission for network devices.
步行資訊運算系統及步行資訊運算方法
(2014-12-11)
胡竹生
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孫冠群
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鄭期元
「資料庫廠商展」
(2014-12-11)
Library
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「資料庫廠商展」活動場景
利用非軸向光源經角膜反射之像散現象估算虹膜影像清晰度之系統
(2014-12-11)
石勝文
16:00「抽獎啦」
(2014-12-11)
Library
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圖書館
16:00「抽獎啦」公開透明童叟無欺； 2014年圖書館週-行動閱讀So easy
「推啤酒杯大賽」與「資料庫廠商展」
(2014-12-11)
Library
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圖書館
「推啤酒杯大賽」與「資料庫廠商展」活動場景暨獎品一覽