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101.
Abdellah Bnouhachem Muhammad Aslam Noor Mohamed Khalfaoui Sheng Zhaohan 《Applied mathematics and computation》2009,215(2):695-706
In this paper, we propose a new modified logarithmic-quadratic proximal (LQP) method for solving nonlinear complementarity problems (NCP). We suggest using a prediction-correction method to solve NCP. The predictor is obtained via solving the LQP system approximately under significantly relaxed accuracy criterion and the new iterate is computed by using a new step size αk. Under suitable conditions, we prove that the new method is globally convergent. We report preliminary computational results to illustrate the efficiency of the proposed method. This new method can be considered as a significant refinement of the previously known methods for solving nonlinear complementarity problems. 相似文献
102.
X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM) studies have been used to analyze the surface of diffusion layer (PTFE/C) and catalyst layer (Pt/C/PTFE) of electrode. Detail analysis of carbon C1s peak showed that the carbon was of the form of C, C-O, CO, CF, CF2 and CF3 with CF2 is more dominated on the surface compared to CF and CF3. The oxygen O1s photoelectron peak showed that the oxygen was of the form of CO and C-O. The platinum was of the form of Pt0 with some Pt oxidized to PtO. The scanning electron microscopy was used to observe the dispersion of Teflon in the diffusion layer, the distribution of platinum in the catalyst layer loaded with 0.38 mg Pt/cm2 and also the cross section of the membrane electrode assembly. The prepared electrode delivers a superior performance compared with the commercial electrode (E-TEK). The difference in performance between the two electrodes is due to the good localization of the platinum particles. 相似文献
103.
Let 2 m n. The paper gives necessary and sufficient conditionson the parameters s1, s2, ..., sm, p1, p2, ..., pm such thatthe Jacobian determinant extends to a bounded operator fromHs1p1 x Hs2p2 x ... x Hsmpm into S'. Here all spaces are definedon Rn or on domains Rn. In almost all cases the regularity ofthe Jacobian determinant is calculated exactly. 相似文献
104.
We give necessary and sufficient conditions on the parameterss1, s2, ..., sm, p1, p2, ..., pm such that the Jacobian determinantextends to a bounded operator from into Z'. Here all spaces are defined on Rn and 2mn. In almostall cases the regularity of the Jacobian determinant is calculatedexactly. 相似文献
105.
106.
Fatima Bouhtit Mehdi Najar Doua Moussa Agha Rahma Melki Mustapha Najimi Khalid Sadki Noureddine Boukhatem Dominique Bron Nathalie Meuleman Abdellah Hamal Laurence Lagneaux Philippe Lewalle Makram Merimi 《Molecules (Basel, Switzerland)》2021,26(2)
Acute myeloid leukemia (AML) is a cancer of the myeloid lineage of blood cells, and treatment for AML is lengthy and can be very expensive. Medicinal plants and their bioactive molecules are potential candidates for improving human health. In this work, we studied the effect of Ptychotis verticillata (PV) essential oil and its derivatives, carvacrol and thymol, in AML cell lines. We demonstrated that a combination of carvacrol and thymol induced tumor cell death with low toxicity on normal cells. Mechanistically, we highlighted that different molecular pathways, including apoptosis, oxidative, reticular stress, autophagy, and necrosis, are implicated in this potential synergistic effect. Using quantitative RT-PCR, Western blotting, and apoptosis inhibitors, we showed that cell death induced by the carvacrol and thymol combination is caspase-dependent in the HL60 cell line and caspase-independent in the other cell lines tested. Further investigations should focus on improving the manufacturing of these compounds and understanding their anti-tumoral mechanisms of action. These efforts will lead to an increase in the efficiency of the oncotherapy strategy regarding AML. 相似文献
107.
108.
Sara El Kharraf Maria Leonor Faleiro Farah Abdellah Soukaïna El-Guendouz El Mestafa El Hadrami Maria Graa Miguel 《Molecules (Basel, Switzerland)》2021,26(18)
Interest in the use of essential oils (EOs) in the biomedical and food industries have seen growing over the last decades due to their richness in bioactive compounds. The challenges in developing an EO extraction process that assure an efficient levels of monoterpenes with impact on biological activities have driven the present study, in which the EO extraction process of rosemary, lavender and citrus was performed by simultaneous hydrodistillation–steam distillation, and the influence of EO composition on biological activities, namely antioxidant, anti-inflammatory, antidiabetic, anti-acetylcholinesterase, anti-tyrosinase, antibacterial, and antibiofilm activity, were evaluated. The EO yields of combinations were generally higher than the individual plants (R. officinalis (Ro), L. angustifolia (La), and C. aurantium (Ca)) extracted by the conventional hydrodistillation. The EOs obtained by this process generally had a better capacity for scavenging the free radicals, inhibiting α-glucosidase, and acetylcholinesterase activities than the individual EOs. The combination of EOs did not improve the ability for scavenging peroxide hydrogen or the capacity for inhibiting lipoxygenase activity. The antioxidant activity or the enzyme inhibition activity could not only be attributed to their major compounds because they presented lower activities than the EOs. The chemical composition of the combination Ro:La:Ca, at the ratio 1/6:1/6:2/3, was enriched in 1,8-cineole, linalool, and linalyl acetate and resulted in lower MIC values for all tested strains in comparison with the ratio 1/6:2/3:1/6 that was deprived on those components. The biofilm formation of Gram positive and Gram negative bacteria was impaired by the combination Ro:La:Ca at a sub-inhibitory concentration. 相似文献
109.
110.
A self-adaptive descent LQP alternating direction method for the structured variational inequalities
Numerical Algorithms - In this paper, by combining the logarithmic-quadratic proximal (LQP) method and alternating direction method, we proposed an LQP alternating direction method for solving... 相似文献