Browsing by Issue Date, starting with "2017-10-16"

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Comparative genomic analyses highlight the contribution of pseudogenized protein-coding genes to human lincRNAs
(2017-10-16)
Liu, Wan-Hsin
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Tsai, Zing Tsung-Yeh
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Tsai, Huai-Kuang
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生物資訊及系統生物研究所
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Institude of Bioinformatics and Systems Biology
Background: The regulatory roles of long intergenic noncoding RNAs (lincRNAs) in humans have been revealed through the use of advanced sequencing technology. Recently, three possible scenarios of lincRNA origins have been proposed: de novo origination from intergenic regions, duplication from other long noncoding RNAs, and pseudogenization from protein-coding genes. The first two scenarios are largely studied and supported, yet few studies focused on the evolution from pseudogenized protein-coding sequence to lincRNA. Due to the non-mutually exclusive nature of these three scenarios and the need of systematic investigation of lincRNA origination, we conducted a comparative genomics study to investigate the evolution of human lincRNAs. Results: Combining with syntenic analysis and stringent Blastn e-value cutoff, we found that the majority of lincRNAs are aligned to intergenic regions of other species. Interestingly, 193 human lincRNAs could have protein-coding orthologs in at least two of nine vertebrates. Transposable elements in these conserved regions in human genome are much less than expectation. Moreover, 19% of these lincRNAs have overlaps with or are close to pseudogenes in the human genome. Conclusions: We suggest that a notable portion of lincRNAs could be derived from pseudogenized protein-coding genes. Furthermore, based on our computational analysis, we hypothesize that a subset of these lincRNAs could have potential to regulate their paralogs by functioning as competing endogenous RNAs. Our results provide evolutionary evidence of the relationship between human lincRNAs and protein-coding genes.
The Design of Subretinal Implant Chip With Shared IrO2 Electrodes and Adaptive Background Current Cancellation Techniques
(2017-10-16)
Wu, Chung-Yu
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電子工程學系及電子研究所
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Department of Electronics Engineering and Institute of Electronics
Revisiting the photophysics of 9-fluorenone: Ultrafast time-resolved fluorescence and theoretical studies
(2017-10-16)
Chang, Chih-Wei
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Solling, Theis I.
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Diau, Eric Wei-Guang
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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
Ultrafast intersystem crossing dynamics of fluorenone in gas and condensed phases were investigated by time-resolved mass spectrometry and fluorescence up-conversion spectroscopy. The former shows the ultrafast Franck-Condon relaxation and the internal conversion dynamics of isolated fluorenone in the gas phase. The latter reveals that the vibrational relaxation time is 2.2 ps and a 110 ps fluorescence lifetime of fluorenone in hexane. The fluorescence lifetime in acetonitrile and dimethylsulfoxide is 16 ns and 15.1 ns, respectively. The potential energy surface along the C=O out of plane bending motion shows that this coordinate is important for ISC in both polar and non-polar solvents. (C) 2017 Elsevier B.V. All rights reserved.
Very large photoresponsiviy and high photocurrent linearity for Ge-dot/SiO2/SiGe photoMOSFETs under gate modulation
(2017-10-16)
Kuo, Ming-Hao
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Hong, Po-Yu
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Liu, Ping-Che
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Lee, Meng-Chun
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Lin, Horng-Chih
We report a novel visible-near infrared photoMOSFET containing a self-organized, gate-stacking heterostructure of SiO2/Ge-dot/SiO2/SiGe-channel on Si substrate that is simultaneously fabricated in a single oxidation step. Our typical photoMOSFETs exhibit very large photoresponsivity of 1000-3000A/W at low optical power (< 0.1 mu W) or large photocurrent gain of 10(3)-10(8)A/A with a wide dynamic power range of at least 6 orders of magnitude (nW-mW) linearity at 400-1250 nm illumination, depending on whether the photoMOSFET operates at V-G = + 3- + 4.5V or -1- + 1V. Numerical simulations reveal that photocarrier confinement within the Ge dots and the SiGe channel modifies the oxide field and the surface potential of SiGe, significantly increasing photocurrent and improving linearity. (C) 2017 Optical Society of America
Growth and characterization of high quality N-type GaSb/GaAs heterostructure by IMF growth mode using MOCVD for low power application
(2017-10-16)
Hsiao, Chih Jen
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Kakkerla, Ramesh Kumar
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Chang, Po Chun
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Lumbantoruan, Franky Juanda
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Lee, Tsu Ting
In this study, we demonstrate the growth of a 150-nm-thick GaSb layer on a GaAs substrate with excellent film quality using the interfacial misfit dislocation growth mode by the Metal-Organic Chemical Vapor Deposition technique. The n-type GaSb epilayer grown on the GaAs substrate has a low threading dislocation density of 3.2 x 10(6) cm(-2) and a surface roughness of approximately 0.8 nm. A high carrier mobility up to 4600 cm(2) V-1 s(-1) with a carrier concentration of 1.2 x 10(17) cm(-3) is achieved in this study. The fabricated Al2O3/GaSb/GaAs MOSCAP demonstrated excellent capacitance-voltage (C-V) characteristics with a small frequency dispersion of approximately 2.8%/decade. The results demonstrate the potential of high-mobility Sb-based materials on GaAs for p-type channel CMOS applications in the future. Published by AIP Publishing.
Unconscious Perceptual Grouping Modulated by Top-Down Attention
(2017-10-16)
Lo, Shih-Yu
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交大名義發表
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National Chiao Tung University
Economic benefits of sharing and redistributing influenza vaccines when shortages occurred
(2017-10-17)
Chen, Sheng-I
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工業工程與管理學系
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Department of Industrial Engineering and Management
Background Recurrent influenza outbreak has been a concern for government health institutions in Taiwan. Over 10% of the population is infected by influenza viruses every year, and the infection has caused losses to both health and the economy. Approximately three million free vaccine doses are ordered and administered to high-risk populations at the beginning of flu season to control the disease. The government recommends sharing and redistributing vaccine inventories when shortages occur. While this policy intends to increase inventory flexibility, and has been proven as widely valuable, its impact on vaccine availability has not been previously reported. Material and methods This study developed an inventory model adapted to vaccination protocols to evaluate government recommended polices under different levels of vaccine production. Demands were uncertain and stratified by ages and locations according to the demographic data in Taiwan. Results When vaccine supply is sufficient, sharing pediatric vaccine reduced vaccine unavailability by 43% and overstock by 54%, and sharing adult vaccine reduced vaccine unavailability by 9% and overstock by 15%. Redistributing vaccines obtained greater gains for both pediatrics and adults (by 75%). When the vaccine supply is in short, only sharing pediatric vaccine yielded a 48% reduction of unused inventory, while other polices do not improve performances. Conclusions When implementing vaccination activities for seasonal influenza intervention, it is important to consider mismatches of demand and vaccine inventory. Our model confirmed that sharing and redistributing vaccines can substantially increase availability and reduce unused vaccines.
Scalable van der Waals Heterojunctions for High-Performance Photodetectors
(2017-10-18)
Yeh, Chao-Hui
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Liang, Zheng-Yong
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Lin, Yung-Chang
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Wu, Tien-Lin
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Fan, Ta
Atomically thin two-dimensional (2D) materials have attracted increasing attention for optoelectronic applications in view of their compact, ultrathin, flexible, and superior photosensing characteristics. Yet, scalable growth of 2D heterostructures and the fabrication of integrable optoelectronic devices remain unaddressed. Here, we show a scalable formation of 2D stacks and the fabrication of phototransistor arrays, with each photosensing element made of a graphene-WS2 vertical heterojunction and individually addressable by a local top gate. The constituent layers in the heterojunction are grown using chemical vapor deposition in combination with sulfurization, providing a clean junction interface and processing scalability. The aluminum top gate possesses a self-limiting oxide around the gate structure, allowing for a self-aligned deposition of drain/source contacts to reduce the access (litigated) channel regions and to boost the device performance. The generated photo current, inherently restricted by the limited optical absorption cross section of 2D materials, can be enhanced by 2 orders of magnitude by top gating. The resulting photoresponsivity can reach 4.0 A/W under an illumination power density of 0.5 mW/cm(2), and the dark current can be minimized to few picoamperes, yielding a low noise-equivalent power of 2.5 x 10(-16) W/Hz(1/2). Tailoring 2D heterostacks as well as the device architecture moves the applications of 2D-based optoelectronic devices one big step forward.
交大e-News第242期-培養「非」型人才交通大學成立百川學士學位學程
(2017-10-19)
國立交通大學秘書室
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Secretariat
Anisotropic Electric Field Effect on the Photoluminescence of CH3NH3PbI3 Perovskite Sandwiched between Conducting and Insulating Films
(2017-10-19)
Awasthi, Kamlesh
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Wang, Chi-Yung
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Fathi, Amir
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Narra, Sudhakar
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Diau, Eric Wei-Guang
Photoluminescence (PL) of a nanocrystalline film of methylammonium lead iodide perovskite (MAPbI(3)) sandwiched between an electrode of a fluorine-doped tin oxide (FTO) layer and an insulating film of poly(methyl methacrylate) is found to increase and decrease significantly with the application of an external electric field (F-ext), depending on the direction of the applied field, based on the measurements of electrophotoluminescence (E-PL) spectra, i.e., field-induced change in PL spectra. The field-induced change in PL intensity is confirmed to originate from the field-induced change in the number of free carriers which induce radiative recombination, based on temporally resolved E-PL measurements. We propose that an internal field (F-int) exists even without application of F-ext. The anisotropic behavior of the effect of F-ext on PL is interpreted in terms of a synergy effect of F-int and F-ext; both fields are additive with the applied field direction from Ag to FTO electrode (positive direction) or subtractive with the opposite applied field direction (negative direction), where FTO is the positive electrode, resulting in an increased or decreased total electric field as well as quenching or enhancement of PL, respectively. The PL lifetime in the nanosecond region increased and decreased with an application of an electric field in the positive and negative directions, respectively, which is attributed to a field-induced change in the concentration of free carriers.
COMMUNICATION SYSTEM AND CHANNEL ESTIMATING METHOD THEREOF
(2017-10-19)
David W. LIN
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Yen-Kai WANG
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Yu-Sheng GUO
A communication system includes at least one transmitting unit and at least one receiving unit. The at least one transmitting unit is configured to transmit at least one input signal after precoding it with at least one precoding matrix. The at least one receiving unit wirelessly coupled with the at least one transmitting unit is configured to receive the at least one precoded input signal, and generate at least one channel quality signal corresponding to the at least one precoded input signal, in which the at least one transmitting unit generates at least one magnitude information estimate or at least one phase information estimate or at least one of both for at least one channel state information according to the at least one channel quality signal, the at least one precoding matrix and at least one noise size signal.
Structural and Photophysical Properties of Methylammonium Lead Tribromide (MAPbBr(3)) Single Crystals
(2017-10-20)
Wang, Kai-Hung
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Li, Liang-Chen
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Shellaiah, Muthaiah
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Sun, Kien Wen
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應用化學系
The structural and photophysical characteristics of MAPbBr(3) single crystals prepared using the inverse temperature crystallization method are evaluated using temperature-dependent X-ray diffraction (XRD) and optical spectroscopy. Contrary to previous research reports on perovskite materials, we study phase transitions in crystal lattice structures accompanied with changes in optical properties expand throughout a wide temperature range of 300-1.5 K. The XRD studies reveal several phase transitions occurred at similar to 210 K, similar to 145 K, and similar to 80 K, respectively. The coexistence of two different crystallographic phases was observed at a temperature below 145 K. The emission peaks in the PL spectra are all asymmetric in line shape with weak and broad shoulders near the absorption edges, which are attributed to the Br atom vacancy on the surface of the crystals. The time-resolved PL measurements reveal the effect of the desorption/adsorption of gas molecules on the crystal surface on the PL lifetimes. Raman spectroscopy results indicate the strong interplays between cations and different halide atoms. Lastly, no diamagnetic shift or split in emission peaks can be observed in the magneto-PL spectra even at an applied magnetic field up to 5 T and at a temperature as low as 1.5 K.
Structure-Property Relationship Study of Donor and Acceptor 2,6-Disubstituted BODIPY Derivatives for High Performance Dye-Sensitized Solar Cells
(2017-10-20)
Yeh, Shih-Chieh
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Wang, Li-Jing
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Yang, Hong-Ming
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Dai, Yu-Huei
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Lin, Chao-Wen
Seven donor and acceptor 2,6-disubstituted 4,4-difluoro-4-bora-3a,4a-diaza-s-indacene (BODIPY) dyes have been synthesized and characterized. Including MPBTCA, which is a known compound, the seven BODIPY dyes have been characterized by varied physical methods, such as UV/Visible absorption spectroscopy, low energy photo-electron spectroscopy (AC-2), and HOMO-LUMO DFT/TDDFT calculation. All seven BODIPY dyes have absorption lambda(max) around 535-545 nm, which is significantly longer than 499 nm of 4,4-difluoro-1,3,5,7,8-pentamethyl-4-bora-3a,4a-diaza-s-indacene (PM 546). Having structural variation on donor group, acceptor group, donor pi-spacer, acceptor pi-spacer, and the substituent on boron, some BODIPY dyes exhibit small extinction coefficients or spectral integrals in solution (MPCtBTCA, MPBT-pyO, MPBTT-pyO, MTBTCA), broadening absorption spectral profile (MTBTCA), weak intramolecular charge transfer characteristics (MPBT-pyO, MPBTT-pyO, MTBTCA), too low LUMO energy level (PPBTCA), or insufficient dye-uptake by TiO2 FTO (MPBT-pyO, MPBTT-pyO, MTBTCA). Two of the seven BODIPY dyes, MPBTCA and MPBTTCA, do not show the adverse properties like other BODIPY dyes. With our improved TiO2 FTO (fluorine doped tin oxide) dyeing method, namely a solution dropping method, high performance dye-sensitized solar cells (DSCs) have been realized by MPBTCA and MPBTTCA photosensitizers. Power conversion efficiencies of 6.3 and 6.4% have been achieved by MPBTCA and MPBTTCA DSCs, respectively. To the best of our knowledge, MPBTCA and MPBTTCA are the most efficient dyes for the donor and acceptor 2,6-disubstituted BODIPY DSCs so far.
Infrared absorption spectra of partially deuterated methoxy radicals CH2DO and CHD2O isolated in solid para-hydrogen
(2017-10-21)
Haupa, Karolina A.
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Johnson, Britta A.
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Sibert, Edwin L., III
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Lee, Yuan-Pern
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應用化學系
The investigation of partially deuterated methoxy radicals is important because the symmetry lowering from C-3v to C-s provides new insights into the couplings between rovibronic states via Jahn-Teller and spin-orbit interactions. The vibrational spectrum of the partially deuterated methoxy radical CH2DO in a matrix of p-H-2 has been recorded. This species was prepared by irradiating a p-H-2 matrix containing deuterated d1-nitritomethane (CH2DONO) at 3.3 K with laser light at 355 nm. The identification of the radical is based on the photochemical behavior of the precursor and comparison of observed vibrational wavenumbers and infrared (IR) intensities with those predicted from a refined quartic, curvilinear, internal coordinate force field calculated with the coupled-cluster singles and doubles with perturbative triples/cc-pVTZ method. CH2DO reacts with H-2 with a rate coefficient (3.5 +/- 1.0) x 10(-3) s(-1). Predominantly c-CHDOH and a negligibly small amount of t-CHDOH were produced. This stereoselectivity results from the reaction H + C-s-CH2DOH, which was demonstrated by an additional experiment on irradiation of a CH2DOH/Cl-2/p-H-2 matrix with ultraviolet and IR light to induce the H + CH2DOH reaction; only c-CHDOH was observed from this experiment. Even though the energies of transition states and products for the formation of c-CHDOH and t-CHDOH differ by only similar to 10 cm(-1), the selective formation of c-CHDOH can be explained by tunneling of the hydrogen atom via an optimal tunneling path. Similarly, the vibronic spectrum for the partially deuterated specie d(2)-methoxy radical (CHD2O) was obtained upon irradiation of d(2)-nitritomethane (CHD2ONO) at 355 nm. Lines associated with the fundamental vibrational modes were observed and assigned; line positions agree with theoretically predicted vibrational wavenumbers. CHD2O reacts with H-2 with a rate coefficient (6.0 +/- 1.4) x 10(-3) s(-1); CD2OH was produced as a major product because the barrier for the formation of CHDOH from H + CHD2OH is greater by similar to 400 cm(-1). Rate coefficients of the decays of CH3O, CH2DO, CHD2O, and CD3O and their corresponding potential energy surfaces are compared. Published by AIP Publishing.
Multifunctional nanoparticles with controllable dimensions and tripled orthogonal reactivity
(2017-10-21)
Wu, Chih-Yu
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Chang, Chun-Wei
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Yuan, Ruei-Hung
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Chiang, Yu-Chih
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Chen, Jiun-Tai
Multifunctional nanoparticles featuring three distinct and orthogonal functionalities for performing catalyst-free click reactions of azide-alkyne and maleimide-thiol and atom transfer radical polymerization (ATRP) are fabricated using a simple chemical vapor deposition copolymerization approach with the flexibility to control the particle size and geometry.
最純真的微笑　熊米屋小愉兒餅乾
(2017-10-22)
蔡亞融
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Department of Communication and Technology
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傳播與科技學系
熊米屋是小愉兒（喜憨兒）親自手作的烘焙坊。但由於目前尚無實體店，他們藉由走出台北捷運街頭推廣叫賣，讓更多人認識熊米屋小愉兒的餅乾。
願這一切都不會失去
(2017-10-22)
關子茵
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Department of Communication and Technology
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傳播與科技學系
想家了，請關注遊子們的思鄉病。
浪浪別哭　讓愛不再流浪
(2017-10-22)
蔡璨竹
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Department of Communication and Technology
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傳播與科技學系
「浪浪別哭」，一間結合動物中途之家的咖啡廳，用滿滿的愛，幫助浪浪們找到適合自己的家。
政治場域的舞台鬥爭
(2017-10-22)
王毓楷
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Department of Communication and Technology
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傳播與科技學系
學校究竟是否屬於政治場域的一環，或許同言論自由與意識型態的權衡一樣難以定論。
安靜的鋒芒　為內向者除去污名
(2017-10-22)
簡梵軒
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Department of Communication and Technology
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傳播與科技學系
在講求競爭與速度的現代社會下，外向者特質較受推崇，然而近幾年內向者的價值也逐漸受到注目與肯定，本文藉由分析雙方差異，探討兩者的特質與重要性。