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101.
We consider the impact of partial positive externalities (imperfect complementarity) among downstream retailers on supply chain performance. We show that double marginalization may fail to exist in a decentralized setting when some retailers carry multiple imperfect complements. By giving a precise characterization on the degree of complementarity, we prove that a decentralized supply chain loses at least 25% of the optimal profit and that its performance degrades rapidly with the complementarity effect. 相似文献
102.
Georgia M. Arvanitis Michael E. Berardini Douglas M. Ho 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(3):m126-m128
The title complex [systematic name: trans‐bis(3‐isopropyl‐7‐oxocyclohepta‐1,3,5‐trienolato)copper(II)], [Cu(C10H11O2)2],is a substance possessing antimicrobial activity. The compound crystallizes in a number of polymorphic forms, the structures for two of which are reported here. Stacks of square‐planar molecules exhibiting weak intermolecular copper–olefin π interactions (not observed in earlier reports on this substance) are described. The molecules have crystallographically imposed inversion symmetry, with stacking and copper–olefin π distances ranging from 3.226 (2) to 3.336 (1) Å. 相似文献
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Gregoria Gregoriou Christiana M. Neophytou Alexandru Vasincu Yiota Gregoriou Haria Hadjipakkou Eftychia Pinakoulaki Marios C. Christodoulou Georgia D. Ioannou Ioannis J. Stavrou Atalanti Christou Constantina P. Kapnissi-Christodoulou Siegfried Aigner Hermann Stuppner Antonis Kakas Andreas I. Constantinou 《Molecules (Basel, Switzerland)》2021,26(16)
Extracts derived from the Ceratonia siliqua L. (carob) tree have been widely studied for their ability to prevent many diseases mainly due to the presence of polyphenolic compounds. In this study, we explored, for the first time, the anti-cancer properties of Cypriot carobs. We produced extracts from ripe and unripe whole carobs, pulp and seeds using solvents with different polarities. We measured the ability of the extracts to inhibit proliferation and induce apoptosis in cancer and normal immortalized breast cells, using the MTT assay, cell cycle analysis and Western Blotting. The extracts’ total polyphenol content and anti-oxidant action was evaluated using the Folin–Ciocalteu method and the DPPH assay. Finally, we used LC-MS analysis to identify and quantify polyphenols in the most effective extracts. Our results demonstrate that the anti-proliferative capacity of carob extracts varied with the stage of carob maturity and the extraction solvent. The Diethyl-ether and Ethyl acetate extracts derived from the ripe whole fruit had high Myricetin content and also displayed specific activity against cancer cells. Their mechanism of action involved caspase-dependent and independent apoptosis. Our results indicate that extracts from Cypriot carobs may have potential uses in the development of nutritional supplements and pharmaceuticals. 相似文献
106.
Vasiliki Palli Georgios Leonis Nikoletta Zoupanou Nikitas Georgiou Maria Chountoulesi Nikolaos Naziris Demeter Tzeli Costas Demetzos Georgia Valsami Konstantinos D. Marousis Georgios A. Spyroulias Thomas Mavromoustakos 《Molecules (Basel, Switzerland)》2022,27(8)
Losartan potassium salt (LSR) is a well-known antihypertensive drug with proven beneficial effects on human health. Its formulation with the non-toxic 2-hydroxypropyl-β-cyclodextrin (2-HP-β-CD) could improve its pharmacological profile. Thus, its molecular interactions are studied using a combination of Differential Scanning Calorimetry (DSC), Nuclear Magnetic Resonance (NMR) and Molecular Dynamics (MD). First, its complexation is shown through Differential Scanning Calorimetry as lyophilization provided distinct thermal properties in comparison to the mixture. The complexation is further proved by utilizing the chemical shift changes in the complexation and T1 values. Furthermore, the reversible favorable complexation was shown by MD calculations. Such physical chemical properties provide evidence that this formulation must be further explored through biological experiments. 相似文献
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Ioannis M. Takakis Phaedon M. Hadjimihalakis Georgia G. Tsantali Helena Pilini 《Journal of heterocyclic chemistry》1992,29(1):123-128
Nitration of the dioxolo-annelated benzenes 11 led to the corresponding dinitro derivatives 12 . Nucleophilic substitution of the latter with azide ion furnished the monoazides 13 which on thermolysis afforded the benzofuroxans 14 . Deoxygenation of furoxans 1a,b,e,f, 2a-c,e,f, 5, 7, 9 and 14 with triphenylphosphine, furnished the respective benzofurazans 3a,b,e,f, 4a-c,e,f, 6, 8, 10 and 15 . 相似文献
110.
We introduce a general adaptive line search framework for solving fixed point and variational inequality problems. Our goals are to develop iterative schemes that (i) compute solutions when the underlying map satisfies properties weaker than contractiveness, for example, weaker forms of nonexpansiveness, (ii) are more efficient than the classical methods even when the underlying map is contractive, and (iii) unify and extend several convergence results from the fixed point and variational inequality literatures. To achieve these goals, we introduce and study joint compatibility conditions imposed upon the underlying map and the iterative step sizes at each iteration and consider line searches that optimize certain potential functions. As a special case, we introduce a modified steepest descent method for solving systems of equations that does not require a previous condition from the literature (the square of the Jacobian matrix is positive definite). Since the line searches we propose might be difficult to perform exactly, we also consider inexact line searches.Preparation of this paper was supported, in part, from the National Science Foundation NSF Grant 9634736-DMI, as well as the Singapore-MIT AllianceAcknowledgments.We are grateful to the associate editor and the referees for their insightful comments and suggestions that have helped us improve both the exposition and the content of this paper. 相似文献