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131.
Luis Santos-Molina Alexa Herrerias Charles N. Zawatsky Ozge Gunduz-Cinar Resat Cinar Malliga R. Iyer Casey M. Wood Yuhong Lin Bin Gao George Kunos Grzegorz Godlewski 《Molecules (Basel, Switzerland)》2021,26(16)
Alcohol consumption is associated with gut dysbiosis, increased intestinal permeability, endotoxemia, and a cascade that leads to persistent systemic inflammation, alcoholic liver disease, and other ailments. Craving for alcohol and its consequences depends, among other things, on the endocannabinoid system. We have analyzed the relative role of central vs. peripheral cannabinoid CB1 receptors (CB1R) using a “two-bottle” as well as a “drinking in the dark” paradigm in mice. The globally acting CB1R antagonist rimonabant and the non-brain penetrant CB1R antagonist JD5037 inhibited voluntary alcohol intake upon systemic but not upon intracerebroventricular administration in doses that elicited anxiogenic-like behavior and blocked CB1R-induced hypothermia and catalepsy. The peripherally restricted hybrid CB1R antagonist/iNOS inhibitor S-MRI-1867 was also effective in reducing alcohol consumption after oral gavage, while its R enantiomer (CB1R inactive/iNOS inhibitor) was not. The two MRI-1867 enantiomers were equally effective in inhibiting an alcohol-induced increase in portal blood endotoxin concentration that was caused by increased gut permeability. We conclude that (i) activation of peripheral CB1R plays a dominant role in promoting alcohol intake and (ii) the iNOS inhibitory function of MRI-1867 helps in mitigating the alcohol-induced increase in endotoxemia. 相似文献
132.
Kunpeng Li Appa Iyer Sivakumar Viswanath Kumar Ganesan 《European Journal of Operational Research》2008
In this paper, we study the problem of synchronized scheduling of assembly and air transportation to achieve accurate delivery with minimized cost in consumer electronics supply chain. This problem was motivated by a major PC manufacturer in consumer electronics industry. The overall problem is decomposed into two sub-problems, which consist of an air transportation allocation problem and an assembly scheduling problem. The air transportation allocation problem is formulated as an integer linear programming problem with the objective of minimizing transportation cost and delivery earliness tardiness penalties. The assembly scheduling problem seeks to determine a schedule ensuring that the orders are completed on time and catch the flights such that the waiting penalties between assembly and transportation is minimized. The problem is formulated as a parallel machine scheduling problem with earliness penalties. The computational complexities of the two sub-problems are investigated. The air transportation allocation problem with split delivery is shown to be solvable. The parallel machine assembly scheduling problem is shown to be NP-complete. Simulated annealing based heuristic algorithms are presented to solve the parallel machine problem. 相似文献
133.
On the Path Coverage Properties of Random Sensor Networks 总被引:1,自引:0,他引:1
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The separation of silver from a uranium matrix has been carried out using Cyanex-471X (triisobutylphosphine sulphide) in xylene. The effects of various parameters such as the Cyanex-471X concentration, the nitric acid molarity, the contact time and the nitrate ion concentration on the extraction of silver have been studied. The silver metal ion species extracted into the organic phase was found to be Ag(NO3)·2S (where S is Cyanex-471X). The stripping of silver into an aqueous medium was carried out with 5% NaHSO3, followed by its determination using ICP-AES. 相似文献
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Mrinal Iyer 《Journal of the mechanics and physics of solids》2011,59(8):1506-1535
The quasi-continuum method has provided many insights into the behavior of lattice defects in the past decade. However, recent numerical analysis suggests that the approximations introduced in various formulations of the quasi-continuum method lead to inconsistencies—namely, appearance of ghost forces or residual forces, non-conservative nature of approximate forces, etc.—which affect the numerical accuracy and stability of the method. In this work, we identify the source of these errors to be the incompatibility of using quadrature rules, which is a local notion, on a non-local representation of energy. We eliminate these errors by first reformulating the extended interatomic interactions into a local variational problem that describes the energy of a system via potential fields. We subsequently introduce the quasi-continuum reduction of these potential fields using an adaptive finite-element discretization of the formulation. We demonstrate that the present formulation resolves the inconsistencies present in previous formulations of the quasi-continuum method, and show using numerical examples the remarkable improvement in the accuracy of solutions. Further, this field theoretic formulation of quasi-continuum method makes mathematical analysis of the method more amenable using functional analysis and homogenization theories. 相似文献
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The present research investigates material transfer associated with the contact between polymers and silicon surfaces. Material transfer from a variety of solid polymers (UHMWPE, Teflon, KEL-F, PMMA, Nylon 66, and PEEK) was studied and characterized by optical microscopy, scanning electron microscopy, atomic force microscopy, and by computer image analysis. Experimental results suggest that material transfer is affected by the Hertz contact area. The number of particles and the total particle area increase with an increase in load and a decrease in the Young's modulus. Also, material transfer increases when the contacting surfaces are rougher. Friction appears to be a weak parameter in the material transfer phenomenon. Additionally, hardness is significant only when normal loading is great enough to initiate plastic deformation in the polymer 相似文献