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181.
182.
Molecular mechanism of a new Laminaria japonica polysaccharide on the suppression of macrophage foam cell formation via regulating cellular lipid metabolism and suppressing cellular inflammation 下载免费PDF全文
183.
Nitrite stabilization of lipids in cured pork 总被引:1,自引:0,他引:1
Peroxidation studies indicated that phospholipids, microsomes and mitochondria from cured pork samples are less susceptible to metmyoglobin/hydrogen peroxide-catalyzed peroxidation than their counterparts from nitrite-free pork samples. The reaction of phospholipids and polyunsaturated fatty acid ethyl esters with dinitrogen trioxide increased their stability to peroxidative changes. Phospholipids from cured pork and those lipids reacted with dinitrogen trioxide were capable of nitrosating a secondary amine. These data, together with infrared analyses, indicate that nitrite or dinitrogen trioxide reacts with unsaturated lipids to form nitro-nitroso derivatives, thus stabilizing the lipids toward peroxidation changes. This mechanism can, in part, explain the antioxidant role of nitrite in cured meats. 相似文献
184.
This study aimed to assess the association between some features of articles title and number of citations in a volume of Addictive Behavior journal. All research articles published in the volume number 32 (2007) in the Addictive Behaviors journal (n = 302) were analyzed by two independent authors. For each article, the following information has been extracted: number of citations up to June 2013 in the Scopus citation database, type of and characteristics of titles, having different words in the keywords, reference to place and presence of an acronym. The summary statistics showed that mean number of citation was 16.36 ± 19.55 times. Articles with combinational title (use of a hyphen or a colon separating different ideas within a sentence) and articles with different words in the keywords (at least two different keywords) had higher number of citations. The number of citations was not correlated with the number of words in the title (r = 0.05, P = 0.325). Our results suggested that some features in the paper such as type of the title and articles with keywords different from words included in the title can help to predict the number of citation counts. These findings can be used by authors and reviewers in order to maximize the impact of articles. The length of title is not associated with citation counts. Therefore, the guide for authors of journals can be more flexible regarding the length of the title. 相似文献
185.
H Brismar M Asghar RM Carey P Greengard A Aperia 《Canadian Metallurgical Quarterly》1998,95(10):5573-5578
The recruitment of G protein-coupled receptors from the cytoplasm to the plasma membrane generally is believed to be a constitutive process. We show here by the use of both confocal microscopy and subcellular fractionation that, for at least one such receptor, this recruitment is regulated and not constitutive. Cells from a proximal tubular-like cell line, LLCPK1 cells, were incubated with either a D1 agonist, a dopamine precursor, or an inhibitor of dopamine metabolism to increase dopamine availability in the cell. Each of the three procedures led to a rapid translocation of dopamine D1 receptors from the cytosol to the plasma membrane. 相似文献
186.
M. Obadat Hosin “David” Lee M. Asghar Bhatti Brian Maclean 《Canadian Metallurgical Quarterly》2003,16(3):100-107
The objective of this research is to develop a microelectromechanical system (MEMS)-based intelligent hybrid Biaxial Strain Transducer (BiAST) sensor for predicting railroad fatigue life based on strain history. The developed BiAST prototype was deployed to collect real-time strain data from the full-scale test track at the Transportation Technology Center (TTCI), near Pueblo, Colorado. The collected strain data were analyzed using the “Binner” fatigue analysis program for counting the load cycles and estimating the fatigue life of a rail structure. Field-testing results of the BiAST were used to evaluate the BiAST prototype with respect to its repeatability, accuracy, and hybridization. BiAST was effective in detecting the dynamic response of a particular wheel and spurious overload events. BiAST can be used to detect passing wheels, train speed, and track condition. 相似文献
187.
H. A. Asghar 《国际能源研究杂志》1991,15(6):509-513
The paper addresses the problem of the estimation of ground losses from underground structures. Existing work has been limited to the cylinder and the sphere for steady state conditions. The numerical solution of the three-dimensional equations for time-dependent conditions requires a prohibitive amount of computing time. The present paper analyses a spherical underground structure with a periodic source at its centre and with periodic ground surface temperature. 相似文献
188.
In this paper the two-point boundary value problem (BVP) of the cantilever deflection at nano-scale separations subjected to van der Waals and electrostatic forces is investigated using analytical and numerical methods to obtain the instability point of the beam. In the analytical treatment of the BVP, the nonlinear differential equation of the model is transformed into the integral form by using the Green's function of the cantilever beam. Then, closed-form solutions are obtained by assuming an appropriate shape function for the beam deflection to evaluate the integrals. In the numerical method, the BVP is solved with the MATLAB BVP solver, which implements a collocation method for obtaining the solution of the BVP. The large deformation theory is applied in numerical simulations to study the effect of the finite kinematics on the pull-in parameters of cantilevers. The centerline of the beam under the effect of electrostatic and van der Waals forces at small deflections and at the point of instability is obtained numerically. In computing the centerline of the beam, the axial displacement due to the transverse deformation of the beam is taken into account, using the inextensibility condition. The pull-in parameters of the beam are computed analytically and numerically under the effects of electrostatic and/or van der Waals forces. The detachment length and the minimum initial gap of freestanding cantilevers, which are the basic design parameters, are determined. The results of the analytical study are compared with the numerical solutions of the BVP. The proposed methods are validated by the results published in the literature. 相似文献
189.
Photooxidative degradation of 4-nitrophenol (4-NP) in UV/H2O2 process: influence of operational parameters and reaction mechanism 总被引:3,自引:0,他引:3
The photooxidative degradation of 4-nitrophenol (4-NP) was studied in the UV/H2O2 process. The effects of applied H2O2 dose, initial 4-NP concentration and UV light intensity have been studied. Degradation was complete in 13 min and follows apparent first-order kinetics. The removal efficiency of 4-NP depends on the operational parameters and increases as the initial concentration of H2O2 and light intensity are increased but it decreases when the initial concentration of 4-NP is increased. From HPLC analysis, major intermediate products were hydroxyl derivatives of 4-NP as a result of photooxidative hydroxylation. 相似文献
190.
Michael Peter Kennedy Muhammad Asfandyar Awan Malik Summair Asghar 《Analog Integrated Circuits and Signal Processing》2013,77(3):415-421
Numerous circuit topologies have been proposed for divide-by-ρ injection-locked frequency dividers (ILFDs), most of which have been optimized for division by even numbers, especially divide-by-2. It has been more difficult to realize division by odd numbers, such as divide-by-3. In this paper we present simulations of an RF CMOS ILFD that can operate equally well in both divide-by-2 and divide-by-3 modes. The ILFD is based on a cross-coupled CMOS LC oscillator with direct injection and an auxiliary injection path. The paper presents two variants of the circuit architecture and Cadence simulations in the multi-GHz frequency range using a standard TSMC 65 nm CMOS process design kit. 相似文献