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41.
Dong-Cheol Woo Chi-Bong Choi Sung-Ho Lee Eunjung Bang Sang-Soo Kim Hyang-Shuk Rhim Sang-Young Kim Bo-Young Choe 《Applied magnetic resonance》2010,38(1):65-74
The purpose of this study was to characterize the neurochemical profiles of various parts of the canine brain using proton
nuclear magnetic resonance spectroscopy, tissue extraction, and external simulated phantom concentration quantification. The
occipital, frontal, and temporal lobes, thalami, cerebellar cortices, and spinal cords of five pure bred adult beagles were
collected, and heavy water solutions for the nuclear magnetic resonance sample were prepared using the methanol–chloroform–water
extraction method. The metabolite concentrations in canine brain tissues were measured and compared with those found in human
and rat brain tissues. In addition, the cross peaks of Lac, Glu/Gln, and mIns were identified using two-dimensional correlation
spectroscopy in the canine frontal cortex. The present study demonstrated the absolute quantification of canine neuronal parts
using in vitro high-resolution magnetic resonance spectroscopy, with tissue extraction used to accurately measure metabolite
concentrations, thus providing valuable metabolic information regarding the various canine neuronal regions. 相似文献
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I. Bang J. A. Mandel H. Steudel O. Folin L. Pincussen F. Fregl F. Emich H. Lieb J. V. Dubsky A. Fodor J. Herzog W. Denis R. D. Bell L. Hannaert R. Wodon C. Vallée A. Polonowski P. E. Howe E. L. Kennaway K. L. Gad-Andresen R. Fosse M. Nicloux und G. Welter 《Fresenius' Journal of Analytical Chemistry》1923,63(1-2):72-80
Ohne Zusammenfassung 相似文献
44.
Shenghan Zhou Houxiang Liu Bang Chen Wenkui Hou Xinpeng Ji Yue Zhang Wenbing Chang Yiyong Xiao 《Entropy (Basel, Switzerland)》2021,23(6)
The traditional sequential pattern mining method is carried out considering the whole time period and often ignores the sequential patterns that only occur in local time windows, as well as possible periodicity. Therefore, in order to overcome the limitations of traditional methods, this paper proposes status set sequential pattern mining with time windows (SSPMTW). In contrast to traditional methods, the item status is considered, and time windows, minimum confidence, minimum coverage, minimum factor set ratios and other constraints are added to mine more valuable rules in local time windows. The periodicity of these rules is also analyzed. According to the proposed method, this paper improves the Apriori algorithm, proposes the TW-Apriori algorithm, and explains the basic idea of the algorithm. Then, the feasibility, validity and efficiency of the proposed method and algorithm are verified by small-scale and large-scale examples. In a large-scale numerical example solution, the influence of various constraints on the mining results is analyzed. Finally, the solution results of SSPM and SSPMTW are compared and analyzed, and it is suggested that SSPMTW can excavate the laws existing in local time windows and analyze the periodicity of the laws, which solves the problem of SSPM ignoring the laws existing in local time windows and overcomes the limitations of traditional sequential pattern mining algorithms. In addition, the rules mined by SSPMTW reduce the entropy of the system. 相似文献
45.
In this Letter, we propose a generic nonlinear coupling coefficient, η(NL)2=η|γ/β?|(fiber2)/|γ/β?|(fiber1), which gives a quantitative measure for the efficiency of nonlinear matching of optical fibers by describing how a fundamental soliton couples from one fiber into another. Specifically, we use η(NL) to demonstrate a significant soliton self-frequency shift of a fundamental soliton, and we show that nonlinear matching can take precedence over linear mode matching. The nonlinear coupling coefficient depends on both the dispersion (β?) and nonlinearity (γ), as well as on the power coupling efficiency η. Being generic, η(NL) enables engineering of general waveguide systems, e.g., for optimized Raman redshift or supercontinuum generation. 相似文献
46.
We demonstrate how the gradient of the tapering in a tapered fiber can significantly affect the trapping and blueshift of dispersive waves (DWs) by a soliton. By modeling the propagation of a fundamental 10?fs soliton through tapered fibers with varying gradients, it is shown that the soliton traps and blueshifts an increased fraction of the energy in its DW when the gradient is decreased. This is quantified by the group-acceleration mismatch between the soliton and DW at the entrance of the taper. These findings have direct implications for the achievable power in the blue edge of a supercontinuum generated in a tapered fiber and explain observations of a lack of power in the blue edge. 相似文献
47.
Do-Gyeong Lee Dae-Young Lee Myeng-Chong Song Jin-Gyeong Cho Myun-Ho Bang Nam-In Baek 《Chemistry of Natural Compounds》2010,46(3):338-339
A new compound, 4-O-(6'-O-p-hydroxybenzoyl-β-D-glucopyranosyl)-cis-p-coumaric acid, was isolated from the fruits of hot pepper (Capsicum annuum L.). The structure of the compound was established on the basis of NMR, FAB-MS, and IR spectroscopic data. 相似文献
48.
We characterize graphs that have intersection representations using unit intervals with open or closed ends such that all ends of the intervals are integral in terms of infinitely many minimal forbidden induced subgraphs. Furthermore, we provide a linear-time algorithm that decides if a given interval graph admits such an intersection representation. 相似文献
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