Browsing by Issue Date, starting with "2013-04-22"

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Increased risk of deep neck infection among HIV-infected patients in the era of highly active antiretroviral therapy-a population-based follow-up study
(2013-04-22)
Liu, Ching-Feng
;
Weng, Shih-Feng
;
Lin, Yung-Song
;
Lin, Chih-Sheng
;
Lien, Ching-Feng
Background: Deep neck infections (DNIs) in HIV-infected patients often produce severe complications, even death. Data on the incidence rates and risks of DNI among HIV-infected patients are scarce, particularly with the widespread use of highly active antiretroviral therapy (HAART). We evaluated the incidence rates and risks for DNI among HIV-infected patients and observed the long-term trends. Methods: A total of 9888 new HIV-infected patients diagnosed in 2001-2007 were included and matched with 49440 randomly selected subjects. The HIV-infected subjects were offered free access to HAART. All subjects were traced until December 2009. A Kaplan-Meier analysis generated the cumulative DNI incidence rate. The adjusted hazard ratio was computed using Cox proportional hazard regressions. Results: From the HIV-infected and comparison cohorts, 222 individuals (57.01 cases per 10000 person-years) and 735 individuals (35.54 cases per 10000 person-years) developed DNI, respectively. The log rank test indicated that patients with HIV had a significantly higher 8-year incidence rate of DNI than the control group (P < 0.0001). The adjusted hazard ratio for developing DNI after an HIV attack during the mean 3.94 years follow-up period was 1.59. The incidence rate and relative risk of DNI were 74.58 (per 10000 person-years) and 2.05 (P < 0.0001). Both figures were highest in the first follow-up year and decreased year-by-year thereafter. Conclusion: The risk of developing DNI is significantly elevated among HIV-infected patients, even with free access to HAART. Additional research is needed to examine the role of HAART in reducing the risk.
交大e-News第139期
(2013-04-22)
Secretariat
;
國立交通大學秘書室
Synthetic Modification of Acyclic Bent Allenes (Carbodicarbenes) and Further Studies on Their Structural Implications and Reactivities
(2013-04-22)
Chen, Wen-Ching
;
Hsu, Yu-Chen
;
Lee, Ching-Yu
;
Yap, Glenn P. A.
;
Ong, Tiow-Gan
The paper describes the synthetic development of Bertrand-type acyclic carbodicarbene scaffolds derived from an unsymmetrical bis(benzimidazol-2-yl)methane bearing two sterically demanding pendant arms, isopropyl (6a) or cyclohexyl (6b). X-ray crystallographic analysis shows that the impact of these pendant arms on the overall structural parameters of carbodicarbenes is minimal. The chemical reactivity of the carbodicarbenes was evaluated with iodomethane to afford compound 7, illustrating its nudeophilic properties. Finally, experiments were also undertaken to investigate the coordination ability of carbodicarbene toward the formation of rhodium carbonyl (10) and palladium allyl complexes (11). The crystal structures of the metal complexes have been determined, revealing that their metal-carbene distances are elongated only slightly, this fact was rationalized on the basis of geometrical steric considerations with regard to the ligand.
Achieving saturation in vertical organic transistors for organic light-emitting diode driving by nanorod channel geometric control
(2013-04-22)
Li, Chang-Hung
;
Stehlin, Fabrice
;
Wang, Kai-Ruei
;
Lin, Yu-Hsin
;
Wieder, Fernand
When conventional field-effect transistors with short channel length suffer from non-saturated output characteristics, this work proposed a vertical channel transistor to operate like a solid-state vacuum tube and exhibit good saturated curves. We utilized deep ultra-violet interference lithography to produce ordered grid-like metal to control the potential profile in vertical channel. We compared experimental and simulated characteristics to investigate the keys to achieve saturation. Finally, with an optimized design, a vertical organic transistor is used to drive a solution-processed white-light organic light-emitting diode to perform a luminescence control (0-260 cd/m(2)) with a 3.3-V base potential swing. (C) 2013 AIP Publishing LLC. [http://dx.doi.org/10.1063/1.4802999]
Electrically tunable-focusing and polarizer-free liquid crystal lenses for ophthalmic applications
(2013-04-22)
Lin, Yi-Hsin
;
Chen, Hung-Shan
;
光電工程學系
;
Department of Photonics
An electrically tunable-focusing and polarizer-free liquid crystal (LC) lens for ophthalmic applications is demonstrated. The optical mechanism of a LC lens used in human eye system is introduced. The polarizer-free LC lens for myopia-presbyopia based on artificial accommodation is demonstrated. The continuously tunable-focusing properties of the LC lenses are more practical in applications for different visional conditions of people. The concept we proposed can also be applied to another types of lenses as long as the focusing properties are tunable. The concept in this paper can also be extensively applied to imaging systems, and projection systems, such as cameras in cell phones, pico projectors, and endoscopes. (C) 2013 Optical Society of America
Phase and dielectric behaviors of a polymorphic liquid crystal doped with graphene nanoplatelets
(2013-04-22)
Wu, Po-Chang
;
Lee, Wei
;
光電學院
;
College of Photonics
We report on the phase behavior and dielectric properties of the liquid crystal (LC) 4'-n-octyloxy-4-cyanobiphenyl dispersed with graphene nanoplatelets (GNPs). The temperature-dependent dielectric permittivity at 10(4) Hz and its derivative with respect to the temperature reveal that the incorporation of GNPs in a LC cell leads to the modification of crystalline polymorphism and shift in phase transition temperature owing to the enhanced positional and orientational order. Additionally, the dielectric data between 1 and 10(3) Hz show that the dopant reduces the ionic concentration and alters the diffusivity in the LC mesophases. (C) 2013 AIP Publishing LLC [http://dx.doi.org/10.1063/1.4802839]
Novel features of the transport coefficients in Lifshitz black branes
(2013-04-23)
Sun, Jia-Rui
;
Wu, Shang-Yu
;
Zhang, Hai-Qing
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物理研究所
;
Institute of Physics
We study the transport coefficients, including the conductivities and shear viscosity of the non-relativistic field theory dual to the Lifshitz black brane with multiple U(1) gauge fields by virtue of the gauge/gravity duality. Focusing on the case of double U(1) gauge fields, we systematically investigate the electric, thermal, and thermoelectric conductivities for the dual nonrelativistic field theory. In the large frequency regime, we find a nontrivial power law behavior in the electric alternating current conductivity when the dynamical critical exponent z > 1 in (2 + 1)-dimensional field theory. The relations between this novel feature and the "symmetric hopping model" in condensed matter physics are discussed. In addition, we also show that the Kovtun-Starinets-Son bound for the shear viscosity to the entropy density is not violated by the additional U(1) gauge fields and dilaton in the Lifshitz black brane. DOI: 10.1103/PhysRevD.87.086005
Digital-to-analog conversion device
(2013-04-23)
Chou Fang-Ding
;
Hung Chung-Chih
A digital-to-analog conversion device is disclosed. The digital-to-analog conversion device comprises a variable delay buffer circuit and a plurality of synchronization circuits. The buffer circuit receives a digital signal with a plurality of bits and sequentially outputs a plurality of first complementary digital signal sets delayed according to the order of from MSB to LSB. Each synchronization circuit receives the first complementary digital signal set and a clock signal, uses the clock signal as the timing reference of the first complementary digital signal set, and outputs a second complementary digital signal set corresponding to the first complementary digital signal set to a digital-to-analog conversion unit, so as to convert the second complementary digital signal sets into an analog signal. The present invention uses the delays respectively corresponding to different input bits to control the timing of current switches, whereby the transient glitches are reduced.
Chip-to-chip multi-signaling communication system with common conductive layer
(2013-04-23)
Su Chau-Chin
;
Ho Ying-Chieh
;
Huang Po-Hsiang
A chip-to-chip multi-signaling communication system with common conductive layer, which comprises a first chip, a second chip, and a common conductive layer, is disclosed. The first chip has at least a first metal pad and a second metal pad. The second chip has at least a first metal pad and a second metal pad. The common conductive layer is to a conductive material and glued directly to the first chip and the second chip. Wherein, the first metal pad of the second chip is aligned with the first metal pad of the first chip for receiving the signal from the first metal pad of the first chip through the common conductive layer. The interference generated by other pads of the first and the second chips is suppressed by the design of the pads and the common conductive layer.
Optical access system for dual service network
(2013-04-23)
Chen Jyehong
;
Lin Chun-Ting
;
Shih Po-Tsung
;
Peng Peng-Chun
;
Dai Sheng-Peng
The present invention relates to an optical access system for dual service network, which mainly comprises an optical modulation device which is used to receive on-off keying (OOK) signal from cable network and radio frequency (RF) signal from wireless network, the optical modulation device then modulates the OOK signal and the RF signal to an optical signal and send out an output optical signal. Lastly, the output optical signal is being delivered to an optical receiving device through an optical fiber transmission channel, and the optical receiving device can access the OOK signal and RF signal from the output optical signal. In addition, the present invention does not require remote nodes (receiver side) to use any optical filter to discern on-off keying signal from cable network and RF signal from wireless network. The present invention can also apply to the field of wavelength-division multiplexing system.
Power-efficient backbone-oriented wireless sensor network, method for constructing the same and method for repairing the same
(2013-04-23)
Huang Kuei-Li
;
Wu Chao-Nan
;
Wang Jui-Tang
;
Tseng Chien-Chao
The present invention discloses a power-efficient backbone-oriented wireless sensor network, a method for constructing the same and a method for repairing the same, wherein energy-rich nodes are used to form backbones linking to a server, and wherein regular nodes having limited energy storage link to the backbones. When one energy-rich node malfunctions, the energy-rich node, which is posterior to the malfunctioning energy-rich node, searches for and links to a linkable neighboring energy-rich node on the backbone. If there is none linkable neighboring energy-rich node, the regular nodes are used to form a temporary tunnel until the malfunctioning energy-rich node has been repaired. The present invention can relieve the influence of hot spots, increase the robustness of the wireless sensor network, and prolong the service life of the wireless sensor network.
下一站，幸福：導讀亞里斯多德《尼可馬各倫理學》第一書與第二書
(2013-04-24)
陳斐婷
;
開放教育推動中心
;
Open Education Office
課程首頁本課程是由交通大學新文藝復興閱讀計畫提供。 96 年 8 月當各大學紛紛摩拳擦掌準備迎接新生的同時，交通大學校長吳重雨則因為一則來自於七月份泰晤士報，有關於英國首相布朗公布其夏日讀書清單的新聞中，看到了他對知識的尊重。在這同時，吳重雨校長也思考著，要如何為學生準備追求知識的環境和激發他們對知識的尊重與喜愛。台積電張忠謀董事長曾陳述他 18 歲進入哈佛那一年，博覽文史哲理工經典群籍，至此奠定了他求知的基礎，並借海明威名言，將其改為「哈佛這一年為人生可帶走的盛宴。」吳重雨校長以張董事長的學習為借鏡，認為學生固然能藉由自我閱讀的方式學習到豐沛的知識，但透過名人、大師親臨現場地介紹經典書籍，更能加深學子們對於書籍的認識與興趣，這也是「新文藝復興閱讀計劃」 ( 以下簡稱 : 「經典名著選讀」 ) 活動展開籌劃的緣由。於是，吳重雨校長便積極敦請「交大通識教育委員會」，接手籌備本計劃的相關活動，而該中心也成為實際施行本計畫的策動、開課以及認證單位。至此，期許交大學子藉由閱讀、聽講來提昇人文素養、開拓視野的「新文藝復興閱讀計劃」，就此展開。
Optical Properties and Exciton Dynamics of Alloyed Core/Shell/Shell Cd1-xZnxSe/ZnSe/ZnS Quantum Dots
(2013-04-24)
Fitzmorris, Bob C.
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Pu, Ying-Chih
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Cooper, Jason K.
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Lin, Yi-Fang
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Hsu, Yung-Jung
In this study we introduce a new method for the onepot synthesis of core/shell/shell alloyed Cd1-xZnxSe/ZnSe/ZnS QDs and examine the effect of the shell coating on the optical properties and exciton dynamics of the alloy core. The photoluminescence (PL) quantum yield is greatly enhanced after shell growth, from 9.6% to 63%. The exciton dynamics were studied by time correlated single photon counting (TCSPC) and fit using integrated singular value decomposition global fitting (i-SVD-GF), which showed the biexponential observed lifetimes on the nanosecond time scale remain the same after shell growth. Using ultrafast transient absorption (TA) spectroscopy and SVD-GF, we have determined that surface passivation by ZnSe and ZnSe/ZnS shells reduces nonradiative recombination primarily on the picosecond time scale. These findings are helpful in directing the development of the next generation of QDs for biological labeling and other applications.
Reversibly Thermoswitchable Two-Dimensional Periodic Gratings Prepared from Tethered Poly(N-isopropylacrylamide) on Silicon Surfaces
(2013-04-24)
Chen, Jem-Kun
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Wang, Jing-Hong
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Cheng, Chih-Chia
;
Chang, Jia-Yaw
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應用化學系
In this study we used atom transfer radical polymerization to graft poly(N-isopropylacrylamide) (PNI-PAAm) onto flat Si substrates. We then applied very large-scale integration and reactive ion etching sequentially to generate 200-nm-scale hole arrays of tethered PNIPAAm as two-dimensional periodic concave gratings (2DPCGs) on the Si surfaces. The hole array structures of tethered PNIPAAm could be created and erased reversibly at 25 and 40 degrees C, respectively, leading to significant. changes in the effective refractive index (n(eff)). The values of neff of the 2DPCGs were related to the depth of their holes generated after etching for various times, resulting in a color change from blue to red that could be observed by the naked eye at incident angles of 10-20 degrees. Moreover, we used effective-medium theory to calculate the filling factors of air inside the 2DPCGs to verify the structural changes of the tethered PNIPAAm. Such designed 2DPCGs of thermorespective hydrogel films have potential applications in temperature-responsive optical devices [e.g., as antireflection structured surfaces (ARSs)] that operate at both visible and near-infrared wavelengths.
Transformation of Polymer Nanofibers to Nanospheres Driven by the Rayleigh Instability
(2013-04-24)
Huang, Yu-Chieh
;
Fan, Ping-Wen
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Lee, Chih-Wei
;
Chu, Chien-Wei
;
Tsai, Chia-Chan
We study the thermal annealing effect of poly(methyl methacrylate) (PMMA) nanofibers made from anodic aluminum oxide (AAO) templates and their transformation to PMMA nanospheres. The PMMA nanofibers are prepared by wetting an AAO template with a 30 wt % PMMA solution, followed by the evaporation of the solvent, After the AAO template is removed by a weak base, the PMMA nanofibers are thermally annealed in ethylene glycol, a nonsolvent for PMMA. The surfaces of the nanofibers undulate and transform into nanospheres, driven by the Rayleigh instability. The driving force for the transformation process is the minimization of the interfacial energy between PMMA nanofibers and ethylene glycol. The transformation times at higher annealing temperatures are shorter than those at lower annealing temperatures. This study provides a facile route to prepare polymer nanospheres which are not accessible by other traditional methods.
Evidence of securin-mediated resistance to gefitinib-induced apoptosis in human cancer cells
(2013-04-25)
Yu, Sheng-Yi
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Liu, Huei-Fang
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Wang, Su-Pei
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Chang, Chia-Ching
;
Tsai, Chuan-Mei
Gefitinib, a tyrosine kinase inhibitor of the epidermal growth factor receptor (EGFR), has been used to treat numerous cancers; however, evidence has shown that cancer cells can become resistant to gefitinib during therapy. Here, we report a human proto-oncogene, securin, which displays resistance to death in cancer cells. Gefitinib treatment decreases securin levels at the protein level by inducing protein instability but did not affect on the securin gene expression. Treatment with gefitinib induced cytotoxicity in various human cancer cell types, including RKO (colon cancer), A549 (lung cancer), BFTC905 (bladder cancer), MCF7 (breast cancer) and A375 (skin cancer). BFTC905 and A549 cells expressed relatively high levels of the phosphorylated and total EGFR proteins; however, A375, MCF7 and RKO cells did not markedly express these proteins. Moreover, following treatment with gefitinib, the securin-wild type cancer cells were more resistant to apoptotic induction than the securin-null cancer cells. Surprisingly, both the securin-wild type and securin-null cancer cells expressed the EGFR protein at similar levels. Treatment with gefitinib induced mitochondrial dysfunction, cytochrome c release, caspase-3 activation and poly (ADP-ribose) polymerase protein cleavage, indicating that apoptosis occurred in these cancer cells. The transfection of a GPF-securin expression vector increased both the proliferation rates and resistance to gefitinib-induced death in these cancer cells. Taken together, these findings demonstrate that the presence of securin promotes resistance to gefitinib-induced apoptosis via an EGFR-independent pathway in human cancer cells. (C) 2013 Elsevier Ireland Ltd. All rights reserved.
METHOD FOR TREATING THE DISLOCATION IN A GAN-CONTAINING SEMICONDUCTOR LAYER
(2013-04-25)
Lee Wei-I
;
Yeh Yen-Hsien
;
Wu Yin-Hao
;
Yu Tzu-Yi
A method for treating the threading dislocation within a GaN-containing semiconductor layer is provided. The method includes a substrate is provided. A GaN-containing semiconductor layer with the threading dislocation is formed on the substrate. An etching process with an etching gas is performed to remove the threading dislocation in the GaN-containing semiconductor layer so as to increase the efficiency for the light emitting device.
INDEPENDENTY-CONTROLLED-GATE SRAM
(2013-04-25)
CHUANG Ching-Te
;
Chen Yin-Nien
;
Hsieh Chien-Yu
;
Fan Ming-Long
;
Hu Pi-Ho
The present invention provides an IG 7T FinFET SRAM, which adopts independently-controlled-gate super-high-VT FinFETs to achieve a stacking-like property, whereby to eliminate the read disturb and half-select disturb. Further, the present invention uses keeper circuits and read control voltage to reduce leakage current of the bit lines during read. Furthermore, the present invention can effectively overcome the problem of the conventional 6T SRAM that is likely to have read errors at low operation voltage.
Polarization and Droplet Size Effects in the Laser-Trapping-Induced Reconfiguration in Individual Nematic Liquid Crystal Microdroplets
(2013-04-25)
Usman, Anwar
;
Chiang, Wei-Yi
;
Uwada, Takayuki
;
Masuhara, Hiroshi
;
應用化學系
We experimentally demonstrate reordering throughout the inside of an individual bipolar nematic liquid-crystalline microdroplet optically trapped by a highly focused laser beam, when the laser powers are above a definite threshold. The threshold depends on the droplet size and laser polarization. A physical interpretation of the results is presented by considering the nonlocal orientations of the nematic liquid-crystal molecules in the droplets with the dimensions on the order of the focal spot diameter or larger. On the basis of the finite size approximation, we show that the dependence of threshold power on the droplet size is calculated to be in qualitative agreement with the experimental data.
Magnetic Resonance Imaging of Mouse Islet Grafts Labeled with Novel Chitosan-Coated Superparamagnetic Iron Oxide Nanoparticles
(2013-04-29)
Juang, Jyuhn-Huarng
;
Shen, Chia-Rui
;
Wang, Jiun-Jie
;
Kuo, Chien-Hung
;
Chien, Yu-Wen
Object: To better understand the fate of islet isografts and allografts, we utilized a magnetic resonance (MR) imaging technique to monitor mouse islets labeled with a novel MR contrast agent, chitosan-coated superparamagnetic iron oxide (CSPIO) nanoparticles. Materials and Methods: After being incubated with and without CSPIO (10 mu g/ml), C57BL/6 mouse islets were examined under transmission electron microscope (TEM) and their insulin secretion was measured. Cytotoxicity was examined in alpha (alpha TC1) and beta (NIT-1 and beta TC) cell lines as well as islets. C57BL/6 mice were used as donors and inbred C57BL/6 and Balb/c mice were used as recipients of islet transplantation. Three hundred islets were transplanted under the left kidney capsule of each mouse and then MR was performed in the recipients periodically. At the end of study, the islet graft was removed for histology and TEM studies. Results: After incubation of mouse islets with CSPIO (10 mu g/mL), TEM showed CSPIO in endocytotic vesicles of alpha- and beta-cells at 8 h. Incubation with CSPIO did not affect insulin secretion from islets and death rates of alpha TC1, NIT-1 and beta TC cell lines as well as islets. After syngeneic and allogeneic transplantation, grafts of CSPIO-labeled islets were visualized on MR scans as persistent hypointense areas. At 8 weeks after syngeneic transplantation and 31 days after allogeneic transplantation, histology of CSPIO-labeled islet grafts showed colocalized insulin and iron staining in the same areas but the size of allografts decreased with time. TEM with elementary iron mapping demonstrated CSPIO distributed in the cytoplasm of islet cells, which maintained intact ultrastructure. Conclusion: Our results indicate that after syngeneic and allogeneic transplantation, islets labeled with CSPIO nanoparticles can be effectively and safely imaged by MR.