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971.
M. Hassan Farshbaf-Shaker 《Numerical Functional Analysis & Optimization》2013,34(11):1321-1349
A scalar Allen-Cahn-MPEC problem is considered and a penalization technique is applied to show the existence of an optimal control. We show that the stationary points of the penalized problems converge to some stationary points of the limit problem, which however are weaker than C-stationarity conditions. 相似文献
972.
973.
Hassan Madkhali Amer Tarawneh Zulfiqar Ali Hoang V. Le Stephen J. Cutler Ikhlas A. Khan Zia Shariat-Madar 《Molecules (Basel, Switzerland)》2021,26(14)
The goal of this study was to assess the pharmacological effects of black tea (Camellia sinensis var. assamica) water extract on human kinin-forming enzymes in vitro. Tea is a highly consumed beverage in the world. Factor XII (FXII, Hageman factor)-independent- and -dependent activation of prekallikrein to kallikrein leads to the liberation of bradykinin (BK) from high-molecular-weight kininogen (HK). The excessive BK production causes vascular endothelial and nonvascular smooth muscle cell permeability, leading to angioedema. The prevalence of angiotensin-converting enzyme inhibitor (ACEI)-induced angioedema appears to be through BK. Both histamine and BK are potent inflammatory mediators. However, the treatments for histamine-mediated angioedema are unsuitable for BK-mediated angioedema. We hypothesized that long-term consumption of tea would reduce bradykinin-dependent processes within the systemic and pulmonary vasculature, independent of the anti-inflammatory actions of polyphenols. A purified fraction of the black tea water extract inhibited both kallikrein and activated FXII. The black tea water extracts inhibited factor XII-induced cell migration and inhibited the production of kallikrein on the endothelial cell line. We compared the inhibitory effects of the black tea water extract and twenty-three well-known anti-inflammatory medicinal herbs, in inhibiting both kallikrein and FXII. Surprisingly, arjunglucoside II specifically inhibited the activated factor XII (FXIIa), but not the kallikrein and the activated factor XI. Taken together, the black tea water extract exerts its anti-inflammatory effects, in part, by inhibiting kallikrein and activated FXII, which are part of the plasma kallikrein–kinin system (KKS), and by decreasing BK production. The inhibition of kallikrein and activated FXII represents a unique polyphenol-independent anti-inflammatory mechanism of action for the black tea. 相似文献
974.
In this paper we present the relaxed inertial proximal algorithm for Ky Fan minimax inequalities. Based on Opial lemma, we propose a weak convergence result to a solution of the problem by eliminating in the algorithm (RIPAFAN) the Browder–Halpern’s factor of contraction. We present after, a first result of strong convergence by adding a strong monotonicity condition. Secondly, we eliminate the strong monotonicity and add a Browder–Halpern’s contraction factor in the algorithm (RIPAFAN) and then ensure the strong convergence to a selected solution with respect to the contraction factor. Some examples are proposed. The first one concerns the convex minimization where the objective function is only controlled with a provided well conditioning. In the second one, we propose monotone set-valued variational inequalities. The last example deals with the problem of fixed point for a nonexpansive set-valued operator. 相似文献
975.
Hassan Hadadzadeh Ali Reza Rezvani Mahmood Karimi Abdolmaleki Khaled Ghasemi Hadi Esfandiari Marzieh Daryanavard 《Journal of chemical crystallography》2010,40(1):48-57
Abstract
Pyridine-2,6-dicarboxylic acid (dipic) was used for the synthesis of a co-crystal with 1,10-phenanthroline-5,6-dione (phen-dione) and a nickel(II) complex. The co-crystal dipic·phen-dione·4H2O (1) has been synthesized and studied by X-ray crystallography. The structure is stabilized with hydrogen bonds between dipic, H2O and phen-dione. It is surprising that there is no direct hydrogen bonding between phen-dione and dipic and yet the molecules co-crystallize in aqueous solution. A new complex of nickel(II), [Ni(phen)(dipic)(H2O)]·4H2O (2), (where phen = 1,10-phenanthroline) has been synthesized and characterized by elemental and thermogravimetric analyses, FT-IR, UV–Vis and 1H-NMR spectroscopy. The structure of (2) has been studied by X-ray crystallography. The coordination around Ni(II) is a distorted octahedron. The crystal packing shows that the dimensionality of (2) is enlarged to 3D, through hydrogen bonds and π–π interactions. Cyclic voltammetry of (2) shows that the Ni(II/I) couple is irreversible. 相似文献976.
Previously, we presented an algorithm for counting Kekulé structures for parallelogram-like benzenoids with holes by counting
descending paths using rectangular meshes with holes. In this article, we describe an algorithm to count Kekulé structures
for convex cyclofusenes using a combinatorial/geometric approach. 相似文献
977.
Javid Hussain Nausheen Bukhari Hidayat Hussain Sajjad Haider Zahid Hassan 《Helvetica chimica acta》2010,93(7):1428-1431
Phlomisamide ( 1 ), a new ceramide, and a new stigmasterol derivative, phlomisteriod ( 2 ), have been isolated from Phlomis cashmeriana. Their structures were elucidated by comprehensive analysis of their 1D‐ (1H‐ and 13C‐NMR) and 2D‐NMR (COSY, HMQC, HMBC), and HR‐EI‐MS data. 相似文献
978.
A novel technique called miniaturized homogeneous liquid–liquid extraction (MHLLE) followed by high performance liquid chromatographic-fluorescence detection (HPLC-FL) was developed for the extraction and determination of some polycyclic aromatic hydrocarbons (PAHs) as model for analytical problem in sediment samples. The method is based on the rapid extraction of PAHs from a methanolic sample solution into 0.5 mL n-hexane, as a solvent of lower density than water. After addition of water, the extracting solvent immediately forms a distinct water-immiscible phase at the top of the vial, which can be easily separated, evaporated and re-dissolved in 25 μL of methanol and injected to the HPLC instrument. The parameters affecting the extraction process such as type and volume of organic extraction solvent, extraction time, and salt addition were investigated and the partition coefficient between methanol/water–n-hexane phases was evaluated and used to predict the extraction efficiency. Under optimal conditions, the limits of detection were estimated for the individual PAHs as 3Sb (three times of the standard deviation of baseline) of the measured chromatogram, are in the range of 0.003–0.04 ng g−1 for sediment samples. The relative recoveries of PAHs at spiking levels of 1.0 ng g−1 for sediment samples were in the range of 81–92%. The method was also applied to a corresponding standard references materials (IAEA-408) successfully. The proposed method is very fast, simple, and sensitive without any need for stirring and centrifugation. 相似文献
979.
Abdollah Salimi Roaya Zand‐Karimi Abdollah Noorbakhash Saied Soltanian 《Electroanalysis》2010,22(20):2434-2442
For the first time silicon nitride (Si3N4) nanoparticles was used for preparation electrochemical biosensor. GOx immobilized on the Si3N4 nanoparticles exhibits facile and direct electrochemistry. The surface coverage and heterogeneous electron transfer rate constant (ks) of immobilized GOx were 6.3×10?13 mol cm?2 and 47.4±0.3 s?1. The sensitivity, linear concentration range and detection limit of the biosensor for glucose detection were 38.57 µA mM?1 cm?2, 25 µM to 8 mM and 6.5 µM, respectively. This biosensor also exhibits good stability, reproducibility and long life time. These indicate Si3N4 nanoparticles is good candidate material for construction of third generation biosensor and bioelectronics devices. 相似文献
980.
Harb HY Collins KD Garcia Altur JV Bowker S Campbell L Procter DJ 《Organic letters》2010,12(23):5446-5449
The use of a silicon stereocontrol element in cyclobutanol and cyclopentanol-forming cyclizations mediated by SmI(2) results in excellent diastereocontrol. The C-Si bond in the products of cyclization provides a versatile handle for further manipulation. An asymmetric route to cyclization substrates involving copper-catalyzed silyl transfer has also been developed. 相似文献