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101.
In this paper we generalize the abstract results of Mock and Marcowich [13, 12] for convergence of discrete Van Roosbroeck systems [12, 13, 17], to the case when the solutions are typically in W1,4-ε and not in H2. These conditions are verified on finite element discretizations. Error estimates are derived when the solution is unique. Due to the singularity at the flat angles, these estimates in the H1 norm are only O(h1/2). The techniques that are presented are broad and may be applied to other type of discretizations. 相似文献
102.
Mohamed Nabil Abd Al Moaty El Sayed Helmy El Ashry Laila Fathy Awad Nihal Ahmed Ibrahim Marwa Muhammad Abu-Serie Assem Barakat Mezna Saleh Altowyan Mohamed Teleb 《Molecules (Basel, Switzerland)》2022,27(8)
The role of metalloenzymes in tumor progression had broadened their application in cancer therapy. Of these, MMPs and CAs are validated druggable targets that share some pivotal signaling pathways. The majority of MMPs or CAs inhibitors are designed as single-target agents. Despite their transient efficacy, these agents are often susceptible to resistance. This set the stage to introduce dual inhibitors of correlated MMPs and CAs. The next step is expected to target the common vital signaling nodes as well. In this regard, VEGFR-2 is central to various tumorigenesis events involving both families, especially MMP-2 and CA II. Herein, we report simultaneous inhibition of MMP-2, CA II, and VEGFR-2 via rationally designed hybrid 1,2,4-triazolo[4,3-a]pyrimidinone acyclo C-nucleosides. The promising derivatives were nanomolar inhibitors of VEGFR-2 (8; IC50 = 5.89 nM, 9; IC50 = 10.52 nM) and MMP-2 (8; IC50 = 17.44 nM, 9; IC50 = 30.93 nM) and submicromolar inhibitors of CA II (8; IC50 = 0.21 µM, 9; IC50 = 0.36 µM). Docking studies predicted their binding modes into the enzyme active sites and the structural determinants of activity regarding substitution and regioselectivity. MTT assay demonstrated that both compounds were 12 folds safer than doxorubicin with superior anticancer activities against three human cancers recording single-digit nanomolar IC50, thus echoing their enzymatic activities. Up to our knowledge, this study introduces the first in class triazolopyrimidinone acyclo C-nucleosides VEGFR-2/MMP-2/CA II inhibitors that deserve further investigation. 相似文献
103.
In continuation to our search for new heterocyclic systems based antiinflammatories, the suggestion and synthesis of some
pyrimidines, thienopyrimidines, and their derivatives, were herein realized. The pharmacological screening showed that many
of these compounds have good antiinflammatory activity. The structure assignments of the new compounds are based on chemical
and spectroscopic evidence. The detailed synthesis, spectroscopic data, and pharmacological properties are reported.
Correspondence: Abd El-Galil Elsayed Amr, National Research Center, Organic Chemistry Department, Cairo, Dokki, Egypt. 相似文献
104.
Nabil Absi 《4OR: A Quarterly Journal of Operations Research》2008,6(3):311-314
This is a summary of the author’s PhD thesis supervised by Philippe Chrétienne and Safia Kedad-Sidhoum and defended in December
2005 at the Université Pierre et Marie Curie (Paris VI). The thesis is written in French and is available from . This work mainly deals with multi-item capacitated lot-sizing problems with setup times, shortages on demand and safety
stock deficit costs. We propose a new mathematical model that includes these new constraints. Three solution approaches are
considered: branch-and-cut, Lagrangean relaxation and MIP-based heuristics approaches. Experimental results showing the effectiveness
and the limit of each approach are presented.
This work was financed by the ANRT and DynaSys S.A. 相似文献
105.
We describe a scheme for rapidly introducing a periodic linear time delay to a train of picosecond laser pulses. By incorporating this scheme in one arm of the Michelson interferometer of a conventional autocorrelator, the second order intensity autocorrelation function of a cw train of picosecond pulses is continuously displayed on an oscilloscope. 相似文献
106.
107.
This is an investigation of the effect of paper-yellowing inhibitors on the rheological, colloidal, and interfacial properties of paper-coating liquids and the associated changes in the liquid surface microstructure. In addition to rheological measurements, we measured the zeta potential and imaged the surface microstructure of coating liquids by transmission electron microscopy (TEM) using an advanced Pt/C replica technique. The zeta potential is related to the concentration of added inhibitors. The images reveal interparticle structuring with increasing concentration of inhibitors. The structuring is related to the interaction between the coating liquids and the inhibitors. It was also found that the viscosity and the elastic modulus increased with inhibitor concentration. The significant changes in mixture properties due to the additives show the importance of the rheological and surface characterization of liquids and the ensuing effect on the corresponding engineering process. 相似文献
108.
We present a numerical study of large deformations of non-linearly elastic membranes. We consider the non-linear membrane model obtained by Le Dret and Raoult using Γ-convergence, in the case of a Saint Venant-Kirchhoff bulk material. We consider conforming P1 and Q1 finite element approximations of the membrane problem and use a non-linear conjugate gradient algorithm to minimize the discrete energy. We present numerical tests including membranes subjected to live pressure loads. 相似文献
109.
In batch statistical process control (BSPC), data from a number of “good” batches are used to model the evolution (trajectory) of the process and they also define model control limits, against which new batches may be compared. The benchmark methods used in BSPC include partial least squares (PLS) and principal component analysis (PCA). 相似文献
110.