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31.
Alexandros Patsourakos 《Letters in Mathematical Physics》1998,45(3):269-276
In this Letter we characterize Lie elements and the elements of the kernel of the Lie bracketing from right to left mapping, using tensor calculus tools. 相似文献
32.
Alexandros Patsourakos 《Letters in Mathematical Physics》1997,41(4):391-402
In this Letter, we construct a natural contracting homotopy in the usual cochain complex of free Lie algebras. As a consequence, we prove that the triple cohomology of Lie algebras coincides with a slightly different form of the standard cohomology theory. 相似文献
33.
Godlewski G Alapafuja SO Bátkai S Nikas SP Cinar R Offertáler L Osei-Hyiaman D Liu J Mukhopadhyay B Harvey-White J Tam J Pacak K Blankman JL Cravatt BF Makriyannis A Kunos G 《Chemistry & biology》2010,17(11):1256-1266
The enzyme fatty acid amide hydrolase (FAAH) catalyzes the in vivo degradation of the endocannabinoid anandamide, thus controlling its action at receptors. A novel FAAH inhibitor, AM3506, normalizes the elevated blood pressure and cardiac contractility of spontaneously hypertensive rats (SHR) without affecting these parameters in normotensive rats. These effects are due to blockade of FAAH and a corresponding rise in brain anandamide levels, resulting in CB? receptor-mediated decrease in sympathetic tone. The supersensitivity of SHR to CB? receptor-mediated cardiovascular depression is related to increased G protein coupling of CB? receptors. Importantly, AM3506 does not elicit hyperglycemia and insulin resistance seen with other FAAH inhibitors or in FAAH?/? mice, which is related to its inability to inhibit FAAH in the liver due to rapid hepatic uptake and metabolism. This unique activity profile offers improved therapeutic value in hypertension. 相似文献
34.
Assessment of block and random copolymer overlayers on polymer optical fibers toward protein detection through electrostatic interaction 下载免费PDF全文
Alexandros El Sachat Anastasia Meristoudi Stergios Pispas Christos Riziotis 《Journal of Polymer Science.Polymer Physics》2015,53(5):327-334
A simple fiber optic based scheme for the selective detection of proteins, based on surface electrostatic interactions, is presented. The implementation of this method is conducted using a modified polymer optical fiber's surface and thin overlayers of properly designed sensitive copolymer materials with predesigned molecular characteristics. Block poly(styrene‐b‐2vinylpyridine) (PS‐b‐P2VP) and random PS‐r‐P2VP copolymers of the same monomers and similar molecular weights, were modified and used as sensing materials. This configuration proved to be efficient concerning the fast detection of charged proteins, and also the efficient discrimination of differently charged proteins such as lysozyme and bovine serum albumin. Results on the sensing performance of block and random copolymers are also discussed drawing conclusion on their efficiency given their considerable different fabrication cost. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2015 , 53, 327–334 相似文献
35.
Alexandros Perivolaris Athena M. Fidelli Ross Inglis Vadim G. Kessler Alexandra M.Z. Slawin 《Journal of Coordination Chemistry》2014,67(23-24):3972-3986
In an attempt to employ salicylic acid (HOsalH), 2,6-dihydroxy benzoic acid {(HO)2PhCO2H}, and naphthalene-1,8-dicarboxylic acid {1,8-naph(CO2H)2} in Mn(III) salicylaldoximate chemistry as a means to alter the structural identity of the hexanucluear clusters usually obtained from this reaction system, we have isolated a family of hexanuclear Mn(III) complexes based on salicyladloxime (saoH2) and 2-hydroxy-1-naphthaldehyde oxime (naphthsaoH2). Five hexanuclear clusters, [Mn6O2(sao)6(HOsal)2(EtOH)4]·EtOH (1·EtOH), [Mn6O2(sao)6{1,8-naph(CO2Me)(CO2)}2(MeOH)6]·3MeOH (2·3MeOH), [Mn6O2(naphthsao)6{1,8-naph(CO2Et)(CO2)}2(EtOH)6] (3·2MeOH), [Mn6O2(naphthsao)6(MeCO2)2(EtOH)4]·2H2O (4·2H2O), and [Mn6O2(naphthsao)6{(HO)2PhCO2}2(EtOH)4]·4EtOH (5·4EtOH), have been synthesized and characterized by single-crystal X-ray crystallography. The magnetic properties of 3, 4, and 5 are discussed. 相似文献
36.
37.
Kruk I Zajdel P van Beek W Bakaimi I Lappas A Stock C Green MA 《Journal of the American Chemical Society》2011,133(35):13950-13956
Na(0.40(2))MnO(2) belongs to a family of mixed Mn(3+) and Mn(4+) porous oxides that contains both octahedral and square pyramidal Mn-O units. Neutron and synchrotron radiation studies identify the presence of both sodium ordering (T(Na) ≈ 310 K) and Mn charge and orbital ordering. Below T(Na), the centrosymmetric Pbam structure adopts an (ab 4c) supercell of Pnnm symmetry that accommodates a coupled commensurate modulation down the c-axis channels of both Na position and occupancy with Mn valence. 相似文献
38.
Margarita Droulia Athina Anastasaki Alexandros Rokotas Marinos Pitsikalis Patrina Paraskevopoulou 《Journal of polymer science. Part A, Polymer chemistry》2011,49(14):3080-3089
Statistical copolymers of methyl methacrylate (MMA) with 2‐methacryloyloxyethyl ferrocenecarboxylate (MAEFC) were prepared by free radical polymerization. The reactivity ratios were estimated using the Fineman‐Ross, inverted Fineman‐Ross, Kelen‐Tüdos, and extended Kelen‐Tüdos graphical methods. Structural parameters of the copolymers were obtained by calculating the dyad monomer sequence fractions and the mean sequence length. The glass‐transition temperature (Tg) values of the copolymers were measured and examined by means of several theoretical equations, allowing the prediction of these Tg values. The thermal degradation behavior of the copolymers was also studied and compared with the respective homopolymers. Cyclic voltammetry was employed to study the electrochemical properties of the copolymers. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011 相似文献
39.
Alexandros PapafilippouMichael A. Terzidis Julia Stephanidou-Stephanatou Constantinos A. Tsoleridis 《Tetrahedron letters》2011,52(12):1306-1309
The zwitterionic intermediates generated from dialkyl azodicarboxylates and triphenylphosphine displayed excellent reactivity toward 3-formylchromones to afford chromeno[2,3-c]pyrazolines and chromeno[2,3-e]tetrazepines. 相似文献
40.
Stavros D. Peroukidis Alexandros G. Vanakaras Sotiris Droulias Demetri J. Photinos 《Liquid crystals》2013,40(10):1430-1435
We study theoretically the optical properties of a two-dimensional lattice of metallic (gold) nanorods immersed within a nematic liquid crystal (NLC) strongly anchored to the surface of the nanorods. The distribution of the director field of the NLC is found by minimising the corresponding total free energy via simulated annealing. Optical properties such as transmittance, reflectance and absorbance of the structure are found by employing a hybrid discrete-dipole approximation/layer-multiple-scattering technique. We show, in particular, that when the NLC is strongly anchored to the nanorods, light absorbance is more efficient compared to the case where the liquid crystal (LC) is aligned by application of an external field. Also, the alignment of the LC molecules via an external field leads to a significant shift of the surface-plasmon resonance of the gold nanorods relative to the strong-anchoring case, an effect which can be exploited in switching applications. We also report that the rate of light absorption is a non-monotonic function of the height of nanorods due to the guiding of EM waves taking place for long enough nanorods. 相似文献