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951.
952.
Miau-Hwa Ko Yu-Lin Hsieh Sung-Tsang Hsieh To-Jung Tseng 《International journal of molecular sciences》2015,16(3):4642-4665
Wallerian degeneration or nerve demyelination, arising from spinal nerve compression, is thought to bring on chronic neuropathic pain. The widely distributed metabotropic glutamate receptor subtype 5 (mGluR5) is involved in modulating nociceptive transmission. The purpose of this study was to investigate the potential effects of mGluR5 on peripheral hypersensitivities after chronic constriction injury (CCI). Sprague-Dawley rats were operated on with four loose ligatures around the sciatic nerve to induce thermal hyperalgesia and mechanical allodynia. Primary afferents in dermis after CCI exhibited progressive decreases, defined as partial cutaneous denervation; importantly, mGluR5 expressions in primary afferents were statistically increased. CCI-induced neuropathic pain behaviors through the intraplantar injections of 2-methyl-6-(phenylethynyl)-pyridine (MPEP), a selective mGluR5 antagonist, were dose-dependently attenuated. Furthermore, the most increased mGluR5 expressions in primary afferents surrounded by reactive Schwann cells were observed at the distal CCI stumps of sciatic nerves. In conclusion, these results suggest that nerve demyelination results in the increases of mGluR5 expression in injured primary afferents after CCI; and further suggest that mGluR5 represents a main therapeutic target in developing pharmacological strategies to prevent peripheral hypersensitivities. 相似文献
953.
Jiun-Jen Chen Ya-Ting Chen Duraisamy Senthil Raja Yu-Hao Kang Pen-Chang Tseng Chia-Her Lin 《Science and Technology of Advanced Materials》2015,16(5)
Three new isostructural metal–organic frameworks (MOFs), [V(OH)(NDC)] (1), [Cr(OH)(NDC)] (2), and [Ga(OH)(NDC)] (3) have been synthesized hydrothermally using 1,4-naphthalene dicarboxylate (NDC) as the linker. These MOFs (1, 2 and 3) have been used as a template for the synthesis of metal-oxide-inserted nanoporous carbon materials. The newly synthesized MOFs and the resulting porous carbon hybrid functional materials have been characterized using powder x-ray diffraction, scanning electron microscopy, transmission electron microscopy, and energy dispersive x-ray spectroscopic analysis. Results show that compounds 2 and 3 form their respective metal oxide nanoparticles on the surface of the carbon materials during carbonization at 800 °C. The gas sorption properties of the new MOFs and their corresponding carbon frameworks have been reported. 相似文献
954.
Kai‐Jun Pai Ming‐De Chien Chu‐Chung Hsieh Ming‐Yao Cheng Cheng‐Kuan Liang Yu‐Kang Lo Yu‐Chen Liu Po‐Jung Tseng 《International Journal of Circuit Theory and Applications》2014,42(11):1154-1171
The high‐power fast charger (HPFC) incorporating a power stage with a controlling loop is presented in this paper. A power stage is composed of an inter‐leaved boost power factor correction and a DC‐DC full‐bridge phase‐shifted (FBPS) converter, and that the HPFC can supply a constant‐voltage (CV) or a constant‐current (CC) power to charge a secondary lithium‐ion battery pack. In addition, the ripple current can be reduced due to the DC‐DC FBPS converter combines with the current‐doubler rectifier at HPFC's output side. Also, the controlling loop is equipped with a voltage compensator and a current compensator, and this design is for the sake of HPFC, which can either operate in CV or CC output mode. Moreover, the shut‐down situation will be prevented by proposed bi‐phase charging controller, when the charging current is adjusted from the fist CC level to the second CC level. Analysis and design considerations of the proposed circuits are presented in details. Experimental results agree well with the theoretical predictions and confirm the validity of the proposed approach. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
955.
In optical communication systems which require the coupling of the light source to the fiber, efficient coupling can be practically realized either using a separate lens or by direct formation of the lens at the fiber end. A novel lensed plastic optical fiber (LPOF) is presented with efficient coupling of the plastic optical fibers with a light source. An aspherical plastic lens was bound with a flattened plastic fiber end by laser transmission welding (LTW) to form an aspherical fiber endface which can provide better coupling efficiency than a spherical fiberface. An analysis demonstrates that LTW can offer strong welding with small heat affected zones that are appropriate for commercial use. In this study a useful method for manufacturing lensed-end fibers is developed and demonstrated experimentally. 相似文献
956.
It has been difficult to develop molecular tools for studying the fungal pathogen Candida albicans because this species uses a non-standard genetic code and is diploid without a complete sexual cycle. Vector systems with regulatable promoters to produce conditional mutants, epitope tags for protein detection and recyclable selection markers are useful for functional study of genes. However, most currently available vectors contain only a subset of desired properties, which limits their application. To combine several useful properties in one vector, the vector pTET25 was initially modified into pTET25M, so that the URA3 gene flanked by dpl200 could be used repetitively. To enable more choices for cloning, a multiple cloning site was introduced at both ends of GFP in pTET25M. GFP expression was induced by doxycycline in a dose- and time-dependent manner when the plasmid was introduced into C. albicans with or without URA3. The applicability of the vectors was verified by constructing strains capable of expressing either the N-terminal GFP fusion of Cdc10 or the C-terminal GFP fusion of Cdc11. Additionally, by replacing the GFP gene of pTET25M with DNA sequence encoding Cdc10 with an epitope tag of six histidine residues at the C-terminus, doxycycline-induced expression of CDC10 was achieved when the expression vector was introduced into C. albicans. This new system allows for inducible expression of a desired C. albicans gene with the advantage of convenience of cloning. It also allows the presence of a recyclable URA3 marker and the detectable expression of fusion or epitope-tagged protein. 相似文献
957.
This study explored the driving behaviors and crash risk of 768 drivers who were under administrative lifetime driver's license revocation (ALLR). It was found that most of the ALLR offenders (83.2%) were still driving and only a few (16.8%) of them gave up driving completely. Of the offenders still driving, 67.6% experienced encountering a police roadside check, but were not detained or ticketed by the police. Within this group, 50.6% continued driving while encountering a police check, 18.0% of them made an immediate U-turn and 9.5% of them parked and exited their car. As to crash risk, 15.2% of the ALLR offenders had at least one crash experience after the ALLR had been imposed. The results of the logistic regression models showed that the offenders’ crash risk while under the ALLR was significantly correlated with their personal characteristics (personal income), penalty status (incarceration, civil compensation and the time elapsed since license revocation), annual distance driven, and needs for driving (working, commuting and driving kids). Low-income offenders were more inclined to have a crash while driving under the ALLR. Offenders penalized by being incarcerated or by paying a high civil compensation drove more carefully and were less of a crash risk under the ALLR. The results also showed there were no differences in crash risk under the ALLR between hit-and-run offences and drunk driving offences or for offenders with a professional license or an ordinary license. Generally, ALLR offenders drove somewhat more carefully and were less of a crash risk (4.3 crashes per million km driven) than legal licensed drivers (23.1 crashes per million km driven). Moreover, they seemed to drive more carefully than drivers who were under short-term license suspension/revocation which previous studies have found. 相似文献
958.
Electron transfer dissociation (ETD) is an alternative peptide dissociation method developed in recent years. Compared with the traditional collision induced dissociation (CID) b and y ion formation, ETD generates c and z ions and the backbone cleavage is believed to be less selective. We have reported previously the application of a statistical data mining strategy, K-means clustering, to discover fragmentation patterns for CID, and here we report application of this approach to ETD spectra. We use ETD data sets from digestions with three different proteases. Data analysis shows that selective cleavages do exist for ETD, with the fragmentation patterns affected by protease, charge states, and amino acid residue compositions. It is also noticed that the c(n-1) ion, corresponding to loss of the C-terminal amino acid residue, is statistically strong regardless of the residue at the C-terminus of the peptide, which suggests that the peptide gas phase conformation plays an important role in the dissociation pathways. These patterns provide a basis for mechanism elucidation, spectral prediction, and improvement of ETD peptide identification algorithms. 相似文献
959.
Since the passage of the Natural Gas Policy Act (NGPA) of 1978, the US Federal Energy Regulatory Commission (FERC) has taken a number of important steps aimed at fostering competition at all levels of the gas industry. With the issuance of Order 451, FERC took the next logical step, eliminating separate price categories for old interstate supplies and establishing a single, higher, and generally above-market price ceiling for this gas. Using a simple model of a gas market with price controls, this paper investigates the general conditions under which the average price of gas may be expected to either rise or fall as a consequence of Order 451. The general conclusion of the paper is that, at least for the US market, the old gas stage of this multi-staged price deregulation should be expected to result in lower average gas prices and greater production. 相似文献
960.
Ampere A. Tseng 《International Journal of Pressure Vessels and Piping》1983,11(4):191-205
A finite element analysis is performed to study the magnitude of attainable prestress of a duplex tube for use in the sodium heated steam generator. This analysis simulates a tube prestress process by incrementally increasing the radial expansion of the inner tube and following with unloading at selected increments. The prestressed tube is then loaded to normal operating conditions. Various radial temperature gradients are evaluated as a basis for any expected operating condition. The finite element analysis indicates that interface contact can be created and maintained during service over a wide range of radial expansion prestress. Interface contact usually increases heat transfer efficiency and reportedly prevents interface motion between the inner and outer tubes, which could cause galling failure. 相似文献