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141.
Jae Won Chang Mohammed Bhuiyan Hsiu‐Ming Tsai Hannah J. Zhang Gang Li Shaghayegh Fathi David C. McCutcheon Lara Leoni Richard Freifelder Chin‐Tu Chen Raymond E. Moellering 《Angewandte Chemie (International ed. in English)》2020,59(35):15161-15165
Herein, we report the development of an 18F‐labeled, activity‐based small‐molecule probe targeting the cancer‐associated serine hydrolase NCEH1. We undertook a focused medicinal chemistry campaign to simultaneously preserve potent and specific NCEH1 labeling in live cells and animals, while permitting facile 18F radionuclide incorporation required for PET imaging. The resulting molecule, [18F]JW199, labels active NCEH1 in live cells at nanomolar concentrations and greater than 1000‐fold selectivity relative to other serine hydrolases. [18F]JW199 displays rapid, NCEH1‐dependent accumulation in mouse tissues. Finally, we demonstrate that [18F]JW199 labels aggressive cancer tumor cells in vivo, which uncovered localized NCEH1 activity at the leading edge of triple‐negative breast cancer tumors, suggesting roles for NCEH1 in tumor aggressiveness and metastasis. 相似文献
142.
Yao Chun-Hsu Chang Tung-Hao Tsai Min-Jia Lai Yuan-Chun Chen Yi-An Chang Yuan-Jen Chen Chin-Hsing 《Journal of Radioanalytical and Nuclear Chemistry》2017,311(2):1277-1286
Volumetric modulated arc therapy (VMAT) was developed to shorten treatment time and increase target conformance. However, a true three-dimensional (3D) gel dosimeter is needed for dose verification. In this study, two clinic cases were adopted: a simple case of lung cancer and a complex case of larynx cancer. For each clinic case, two treatment plans were generated for the same planning target volume using VMAT and intensity modulated radiation therapy calculation software packages. An N-isopropylacrylamide (NIPAM) polymer gel dosimeter was used for 3D dose verification. In addition, the dose characteristics of the NIPAM gel dosimeter were investigated for the two clinic cases.
相似文献143.
We present in this paper a finite difference solver for Maxwell's equations in non‐staggered grids. The scheme formulated in time domain theoretically preserves the properties of zero‐divergence, symplecticity, and dispersion relation. The mathematically inherent Hamiltonian can be also retained all the time. Moreover, both spatial and temporal terms are approximated to yield the equal fourth‐order spatial and temporal accuracies. Through the computational exercises, modified equation analysis and Fourier analysis, it can be clearly demonstrated that the proposed triple‐preserving solver is computationally accurate and efficient for use to predict the Maxwell's solutions. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
144.
Yi-Jung Liu Chih-Hung Yen Chia-Hao Hsu Kuo-Hui Yu Li-Yang Chen Tsung-Han Tsai Wen-Chau Liu 《Optical Review》2009,16(6):575-577
An interesting GaN-based light emitting diode (LED) using a 50 nm indium oxide (In2O3)/250 nm indium-tin oxide (ITO) mixed structure to replace the commonly used ITO (250 nm) current spreading layer is fabricated
and studied. Use of the In2O3 layer could reduce the contact resistance of p-GaN in LEDs. In addition, this highly-resistive In2O3 layer, below the ITO layer could improve the current spreading performance. Experimentally, at room temperature, using this
mixed structure, the luminous and EL intensities are enhanced by 17.7 and 17.1%, respectively. 相似文献
145.
Chen Kai-Huang Cheng Chien-Min Shih Chia-Chi Tsai Jen-Hwan 《Applied Physics A: Materials Science & Processing》2011,103(4):1173-1177
In this study, the ferroelectricity of as-deposited Bi3.9La0.1Ti2.9V0.1O12 (BLTV), Bi3.9Ti2.9V0.1O12 (BTV), and Bi4Ti3O12 (BIT) thin films was prepared and compared by rf magnetron sputtering technology. For the BLTV, BTV, and BIT thin films deposited
on Pt/Ti/SiO2/Si and SiO2/Si substrate, the physical and electrical characteristics of lanthanum doped BTV (BLTV) were better than those of BIT and
BTV thin films. Regarding the physical properties, the micro-structure of as-deposited BTV and BLTV thin films were obtained
and compared by XRD patterns and SEM images. The BLTV and BTV thin films were also exhibited clear the ferroelectricity. The
remanent polarization (P
r
) of as-deposited BLTV thin films was 11 μC/cm2 as the measured frequency of 100 kHz. It was higher than those of BTV thin films. Finally, the polarization of BLTV thin
film capacitor decreased by 9%, while that of the BTV decreased by 15% after the fatigue test with 109 switching cycles. 相似文献
146.
S. P. Changlai H. H. Tsai S. C. Tsai H. P. Chen C. L. Chang Y. H. Yao C. Y. Chen 《Journal of Radioanalytical and Nuclear Chemistry》2012,291(3):859-863
This work is the first evaluation of environmental gamma exposure rates by the Nuclear Medicine Department at Lin Shin Hospital
(LSH) in Taichung with Thermoluminescent dosimeter (TLD-100H) during the Fukushima Nuclear Power Plant (FNPP) accident. After
the 9.0 MW strong earthquake hit northern Japan on March 11, 2011, a TLD-100H was used to monitor environmental kerma rate at Taichung
(2,500 km away from northern Japan) from Mar-08 to Apr-09, 2011 and evaluated kerma rate due to global fallout of the sever
FNPP accidents. Exposure rates varied widely among positions close to the PET/CT facility. Observed kerma rates of up to 4.12 ± 0.62 mSv mo−1 indicated an explicit, heavy leakage of photon through the PET/CT facility. No significant contributions were detected at
Taichung, Taiwan. Hence, the health effect cause by the “extra radiation” from FNPP accidents is negligible. As this was a
rare case of environmental monitoring during a nuclear power plant accident, its findings are of considerable significance. 相似文献
147.
148.
Tsung-Hsuan Tsai Tse-Wei Chen Shen-Ming Chen Ramiah Sarawathi 《Russian Journal of Electrochemistry》2012,48(3):291-301
The NiHCF-PEDOT, CuHCF-PEDOT and MnHCF-PEDOT films were prepared on glassy carbon electrode (GCE) by multiple scan cyclic
voltammetry and characterized using cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and scanning electron
microscope (SEM) techniques. The advantages of these films are demonstrated for selectivity detection of ascorbic acid using
cyclic voltammetry and amperometric method. Interestingly, the NiHCF-PEDOT and CuHCF-PEDOT modified electrodes exhibited a
wide linear response range (5 × 10−6−3 × 10−4 M, R
2 = 0.9973 and 1.8 × 10−3−1.8 × 10−2 M, R
2 = 0.9924). The electrochemical sensors facilitated the oxidation of AA but not responded to other electroactive biomolecules
such as dopamine, uric acid, H2O2, glucose. The difference is MnHCF-PEDOT/GCE that no response to AA. In addition, the NiHCF-PEDOT and CuHCF-PEDOT modified
electrodes exhibited a distinct advantage of simple preparation, specificity, stability and reproducibility. 相似文献
149.
Chia-Chi Shih Yu-Jen Chen Sean Wu Cheng-Che Tsai I-Min Jiang 《Optics Communications》2009,282(19):3977-3981
This study presents an integrated device that consists of a directional coupler and an electro-optic switch. The device is designed to include a nematic liquid crystal cell, comprising a grating-like electrode. Applying the appropriate voltage to the cell yields a periodically distributed refractive index. An incident polarized beam will couple to an adjacent channel if it is parallel to the channel. The coupling efficiency is controlled by applied voltage. An obliquely injected polarized beam will be reflected and refracted in the channel, and propagated along a curved path. The route of the beam can be controlled by applying the voltage. A multiport routing was achieved for voltage modulation. In addition, the distribution of refractive index is also investigated by employing conoscopic technique experimentally and numerically. 相似文献
150.
The effect of polarization-matched AlGaInN electron-blocking layer and barrier layer on the optical performance of blue InGaN light-emitting diodes is numerically investigated. The polarization-matched AlGaInN electron-blocking layer and barrier layer are employed in an attempt to reduce the polarization effect inside the active region of the light-emitting diodes. The simulation results show that the polarization-matched AlGaInN electron-blocking layer is beneficial for confining the electrons inside the quantum well region. With the use of both polarization-matched AlGaInN electron-blocking layer and barrier layer, the optical performance of blue InGaN light-emitting diodes is greatly improved due to the increased overlap of electron and hole wavefunctions. The method proposed in this paper can also be applied to the light-emitting diodes operating in other spectral range. 相似文献