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Cover Picture: Fluorescent Silica Nanoparticles with Multivalent Inhibitory Effects towards Carbonic Anhydrases (Chem. Eur. J. 29/2015) 下载免费PDF全文
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A new retail facility is to locate and its service quality is to determine where similar facilities of competitors offering the same goods are already present. The market share captured by each facility depends on its distance to customers and its quality, which is described by a probabilistic Huff-like model. In order to maximize the profit of the new facility, a two-stage method is developed, which takes into account the reactions of the competitors. In the quality decision stage, the competitive decision process occurring among facilities is modelled as a game, whose solution is given by its Nash equilibrium. The solution, which can be represented as functions of the location of the new facility, is obtained by analytical resolution of a system of equations in the case of one facility in the market or by polynomial approximation in the case of multiple facilities. In the location decision stage, an interval based global optimization method is used to determine the best location of the new facility. Numerical experiments on randomly generated instances demonstrate the effectiveness of the method. 相似文献
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Ahmed Nasreddine Benaichouche Hamouche Oulhadj Patrick Siarry 《Journal of Heuristics》2016,22(4):383-404
In this paper, we propose a grayscale image segmentation method based on a multiobjective optimization approach that optimizes two complementary criteria (region and edge based). The region-based fitness used is the improved spatial fuzzy c-means clustering measure that is shown performing better than the standard fuzzy c-means (FCM) measure. The edge-based fitness used is based on the contour statistics and the number of connected components in the image segmentation result. The optimization algorithm used is the multiobjective particle swarm optimization (MOPSO), which is well suited to handle continuous variables problems, the case of FCM clustering. In our case, each particle of the swarm codes the centers of clusters. The result of the multiobjective optimization technique is a set of Pareto-optimal solutions, where each solution represents a segmentation result. Instead of selecting one solution from the Pareto front, we propose a method that combines all solutions to get a better segmentation. The combination method takes place in two steps. The first step is the detection of high-confidence points by exploiting the similarity between the results and the membership degrees. The second step is the classification of the remaining points by using the high-confidence extracted points. The proposed method was evaluated on three types of images: synthetic images, simulated MRI brain images and real-world MRI brain images. This method was compared to the most widely used FCM-based algorithms of the literature. The results demonstrate the effectiveness of the proposed technique. 相似文献
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Sakhri Nasreddine Menni Younes Chamkha Ali J. Lorenzini Giulio Ameur Houari Kaid Noureddine Bensafi Mohammed 《Journal of Thermal Analysis and Calorimetry》2021,145(6):3349-3358
Journal of Thermal Analysis and Calorimetry - Arid regions around the world are characterized by hard summer and winter seasons, which leads to thermal discomfort. The southwest of Algeria is... 相似文献
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Hamza Mechchate Aicha El Allam Nasreddine El Omari Naoufal El Hachlafi Mohammad Ali Shariati Polrat Wilairatana Mohammad S. Mubarak Abdelhakim Bouyahya 《Molecules (Basel, Switzerland)》2022,27(7)
Aging is a continuous process over time that is mainly related to natural alterations in mechanical–biological processes. This phenomenon is due to several factors, including the time and energy of biological processes. Aging can be attributed to biological factors such as oxidative stress, cell longevity, and stem cell senescence. Currently, aging is associated with several diseases, such as neurodegenerative diseases, cancer, and other diseases related to oxidative stress. In addition, certain natural molecules, including those derived from vegetables, have shown the ability to delay the aging process. Their effects are linked to different mechanisms of action, such as tissue regeneration and the activation of longevity and anti-senescence genes. The present work discusses the impact of vegetables, and bioactive compounds isolated from vegetables, against the physiological and pathological aging process and accompanying human diseases. 相似文献
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Superionic-protonic behavior of a new mixed sodium dihydrogen phosphate-arsenate at room temperature
Khaled Jarraya Nasreddine Ennaceur Mimoun El MarssiTahar Mhiri 《Physica B: Condensed Matter》2011,406(8):1546-1549
The elaborate mixed material of the formula NaH2(PO4)0.48(AsO4)0.52·H2O denoted by NDAP belongs to a group of compounds having properties that are intermediate between those of a normal salt and an acid, and undergoes a transition from a paraelectric to a superprotonic phase transition at room temperature. The temperature phase transition (296 K) leading to a superionic-protonic phase characterized by an unusual high conductivity at room temperature was found. The conductivity relaxation parameters associated with the high-disorder protonic conduction have been determined from the analysis of the M″/M″max spectrum and measured in a wide temperature range. Transport properties in this material appear to be due to proton hopping mechanism. 相似文献
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Caroline Barrère Marie Hubert-Roux Carlos Afonso Majed Rejaibi Nasreddine Kebir Nicolas Désilles Laurence Lecamp Fabrice Burel Corinne Loutelier-Bourhis 《Analytica chimica acta》2014
The structural characterization of polyamides (PA) was achieved by tandem mass spectrometry (MS/MS) with a laser induced dissociation (LID) strategy. Because of interferences for precursor ions selection, two chemical modifications of the polymer end groups were proposed as derivatization strategies. The first approach, based on the addition of a trifluoroacetic acid (TFA) molecule, yields principally to complementary bn and yn product ions. This fragmentation types, analogous to those obtained with peptides or other PA, give only poor characterization of polymer end-groups [1]. A second approach, based on the addition of a basic diethylamine (DEA), permits to fix the charge and favorably direct the fragmentation. In this case, bn ions were not observed. The full characterization of ω end group structure was obtained, in addition to the expected yn and consecutive fragment ions. 相似文献
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Fluorescent Silica Nanoparticles with Multivalent Inhibitory Effects towards Carbonic Anhydrases 下载免费PDF全文
Dr. Nadia Touisni Nasreddine Kanfar Dr. Sébastien Ulrich Prof. Dr. Pascal Dumy Prof. Dr. Claudiu T. Supuran Prof. Dr. Ahmad Mehdi Dr. Jean‐Yves Winum 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(29):10306-10309
Multifunctional silica nanoparticles decorated with fluorescent and sulfonamide carbonic anhydrase (CA) inhibitors were prepared and investigated as multivalent enzyme inhibitors against the cytosolic isoforms hCA I and II and the transmembrane tumor‐associated ones hCA IX and XII. Excellent inhibitory effects were observed with these nanoparticles, with KI values in the low nanomolar range (6.2–0.67 nM ) against all tested isozymes. A significant multivalency effect was seen for the inhibition of the monomeric enzymes hCA I and II compared to the dimeric hCA IX and hCA XII isoforms, where no multivalent effect was observed, suggesting that the multivalent binding is occurring through enzyme clustering. 相似文献