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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
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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
107.
Dr. Abed Saady Georgia K. Malcolm Dr. Matthew P. Fitzpatrick Dr. Noel Pairault Dr. Graham J. Tizzard Dr. Soran Mohammed Prof. Ali Tavassoli Prof. Stephen M. Goldup 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2024,136(16):e202400344
Inspired by interlocked oligonucleotides, peptides and knotted proteins, synthetic systems where a macrocycle cages a bioactive species that is “switched on” by breaking the mechanical bond have been reported. However, to date, each example uses a bespoke chemical design. Here we present a platform approach to mechanically caged structures wherein a single macrocycle precursor is diversified at a late stage to include a range of trigger units that control ring opening in response to enzymatic, chemical, or photochemical stimuli. We also demonstrate that our approach is applicable to other classes of macrocycles suitable for rotaxane and catenane formation. 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