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111.
In a recent paper, Ghenciu and Lewis studied strong Dunford-Pettis sets and made the following two assertions:
While the statements are correct, the proofs are flawed. The difficulty with the proofs is discussed, and a fundamental result
of Elton is used to establish a simple lemma which leads to quick proofs of both (1) and (2). 相似文献
(1) | The Banach space X * contains a nonrelatively compact strong Dunford-Pettis set if and only if ℓ∞ ↪ X *. |
(2) | If c 0 ↪ Y and H is a complemented subspace of X so that H * is a strong Dunford-Pettis space, then W(X, Y) is not complemented in L(X, Y). |
112.
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114.
The effects of grape seeds polyphenols on SKH-1 mice skin irradiated with multiple doses of UV-B 总被引:1,自引:0,他引:1
Filip A Daicoviciu D Clichici S Bolfa P Catoi C Baldea I Bolojan L Olteanu D Muresan A Postescu ID 《Journal of photochemistry and photobiology. B, Biology》2011,105(2):133-142
The study investigated the protective activity of red grape seeds (Vitis vinifera L, Burgund Mare variety) (BM) extracts in vivo on multiple doses of ultraviolet radiation (UV)-B-induced deleterious effects in SKH-1 mice skin. Eighty 8-weeks-old female SKH-1 mice were divided into 8 groups: control, vehicle, UV-B irradiated, vehicle+UV-B irradiated, BM 2.5mg polyphenols (PF)/cm(2)+UV-B irradiated, BM 4 mg PF/cm(2)+UV-B irradiated, UV-B+BM 2.5mg PF/cm(2), UV-B+BM 4 mg PF/cm(2). The extract was applied topically before or after each UV-B exposure (240 mJ/cm(2)), for 10 days consecutively. The antioxidant activity of BM extract is higher than gallic acid (k(BM)=0.017, k(gallic acid)=0.013). Multiple doses of UV-B generated the formation of cyclobutane pyrimidine dimers (CPDs) and sunburn cells, increased glutathione peroxidase (GPx) and catalase (CAT) activities respectively glutathione (GSH) and IL-1β levels in skin. In group treated with 2.5mg PF/cm(2) before UV-B irradiation BM extract inhibited UV-B-induced sunburn cells, restored the superoxide dismutase (MnSOD) activity, increased insignificantly CAT and GPx activities and reduced IL-1β level. The BM 4.0 mg PF/cm(2) treatment decreased GSH level and reduced the percentage of CPDs positive cells in skin. Both doses of BM extract administered after UV-B irradiation increased the MnSOD and GPx activities and reduced the formation of sunburn cells in skin. Our results suggest that BM extract might be a potential chemo-preventive candidate in reducing the oxidative stress and apoptosis induced by multiple doses of UV-B in skin. 相似文献
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116.
László Csaba BenczeCsaba Paizs Monica Ioana To?aFlorin Dan Irimie 《Tetrahedron: Asymmetry》2011,22(6):675-683
Possible routes for the enzymatic transformation of various substituted 1-(5-phenylfuran-2-yl)ethane-1,2-diols and their mono- and diacetylated counterparts were studied. Combining the regioselectivity of LPS mediated acylation of the starting racemic diols, the stereoselectivity of LAK shown in the enantiomer selective transformation of the previously formed racemic primary acetates and the LPS mediated mild hydrolysis-alcoholysis of the resolution products, an efficient preparative scale procedure for the synthesis of various highly enantiomerically enriched (R)- and (S)-phenylfuran-2-yl-ethane-1,2-diols has been developed. 相似文献
117.
Ioana Varduca Enache Lucia Mutihac Amel Ben Othman Jacques Vicens 《Journal of inclusion phenomena and macrocyclic chemistry》2011,71(3-4):537-543
The native and methyl ester amino acids have been extracted by calix[4]azacrowns 1 (1,3-[ethylene-bis-aminocarbonylmethoxy)]-p-tert-butylcalix[4]arene) and 2 (1,3-[propylene-bis-aminocarbonylmethoxy)]-p-tert-butyl-calix[4]arene) from an aqueous phase into a chloroform phase and transported through a chloroform liquid membrane as ion pairs in the presence of picrate or tropaeolin 00 as counter ions aiming their separation. The amino acids under study exhibited good extractability by calix[4]azacrowns 1 and 2. Both receptors 1 and 2 showed good extractability towards amino acids under study. The results are discussed in term of correlation of structural properties of amino acids and calix[4]azacrowns involved in experiments. In this respect, the influence of chain length of receptors upon extraction and transport of amino acids, and the nature of anions used as counter ions are evaluated. 相似文献
118.
Ioana Pomparău 《PAMM》2013,13(1):419-420
In the paper [1], a direct version of the classical Kaczmarz algorithm was proposed, which gives us in only one iteration a solution of an arbitrary consistent system of linear equations. Unfortunately, as any direct method applied to large sparse matrices, this algorithm is based on some modifications of the system matrix sparsity structure such that a big fill-in appears. In order to overcome this difficulty, in the present paper we propose a modified version of this direct Kaczmarz algorithm in which the transformations applied to the system matrix try to conserve the initial sparsity structure. This transformations are done via clustering using Jaccard and Hamming distances. The modified Kaczmarz algorithm is no more a direct method, but we obtain an acceleration of convergence with respect to the classical Kaczmarz algorithm. Numerical experiments which ilustrate the efficiency of our algorithm are also presented. (© 2013 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
119.
We correct a few errors that appeared in [Convergence of invariant measures for singular stochastic diffusion equations, Stochastic Process. Appl. 122 (4) (2012) 1998–2017] by I. Ciotir and J.M. Tölle. 相似文献
120.
Elena Fertman Sergiy Dolya Vladimir Desnenko Anatoly Beznosov Marcela Kajňaková Alexander Feher 《Journal of magnetism and magnetic materials》2012
A detailed study of the low-temperature magnetic state and the relaxation in the phase-separated colossal magnetoresistance Nd2/3Ca1/3MnO3 perovskite has been carried out. Clear experimental evidence of the cluster-glass magnetic behavior of this compound has been revealed. Well defined maxima in the in-phase linear ac susceptibility χ′(T) were observed, indicative of the magnetic glass transition at Tg∼60 K. Strongly divergent zero-field-cooled and field-cooled static magnetizations and frequency dependent ac susceptibility are evident of the glassy-like magnetic state of the compound at low temperatures. The frequency dependence of the cusp temperature Tmax of the χ′(T) susceptibility was found to follow the critical slowing down mechanism. The Cole–Cole analysis of the dynamic susceptibility at low temperature has shown extremely broad distribution of relaxation times, indicating that spins are frozen at “macroscopic” time scale. Slow relaxation in the zero-field-cooled magnetization has been experimentally revealed. The obtained results do not agree with a canonical spin-glass state and indicate a cluster glass magnetic state of the compound below Tg, associated with its antiferromagnetic–ferromagnetic nano-phase segregated state. It was found that the relaxation mechanisms below the cluster glass freezing temperature Tg and above it are strongly different. Magnetic field up to about μ0H∼0.4 T suppresses the glassy magnetic state of the compound. 相似文献