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131.
Tomasz Brzezinski 《Proceedings of the American Mathematical Society》2000,128(8):2261-2270
Entwined modules arose from the coalgebra-Galois theory. They are a generalisation of unified Doi-Hopf modules. In this paper, Frobenius properties and Maschke-type theorems known for Doi-Hopf modules are extended to the case of entwined modules.
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Products of reactions between chloropentafluorobenzene and strong N-bases (DBN, DBU, TBD, and MTBD) in polar aprotic solvents and in the presence of water were isolated and identified by analytical and spectroscopic methods. The products of these dehydrohalogenation reactions are apropriate lactams, and if the TBD N-base is used, a condensation occurs with formation of benzimidazole derivative. All the products are not formed directly in the nucleophilic substitution by N-bases but after the hydrolyses of the N-bases with formation of amines known as hard nucleophiles. 相似文献
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Patryk Brzezinski 《Mathematische Nachrichten》2013,286(17-18):1726-1743
This paper deals with volume estimates for hyperplane sections of the simplex and for m‐codimensional sections of powers of m‐dimensional Euclidean balls. In the first part we consider sections through the centroid of the n‐dimensional regular simplex. We state a volume formula and give a lower bound for the volume of sections through the centroid. In the second part we study the extremal volumes of m‐codimensional sections “perpendicular” to of unit balls in the space for all . We give volume formulas and use them to show that the normal vector (1, 0, …, 0) yields the minimal volume. Furthermore we give an upper bound for the ‐dimensional volumes for natural numbers . This bound is asymptotically attained for the normal vector as . 相似文献
137.
Vittorio Canale Magdalena Kotaska Anna Dziubina Matylda Stefaniak Agata Siwek Gabriela Starowicz Krzysztof Marciniec Patryk Kasza Grzegorz Sataa Beata Duszyska Xavier Bantreil Frdric Lamaty Marek Bednarski Jacek Sapa Pawe Zajdel 《Molecules (Basel, Switzerland)》2021,26(13)
The complex pathophysiology of depression, together with the limits of currently available antidepressants, has resulted in the continuous quest for alternative therapeutic strategies. Numerous findings suggest that pharmacological blockade of α2-adrenoceptor might be beneficial for the treatment of depressive symptoms by increasing both norepinephrine and serotonin levels in certain brain areas. Moreover, the antidepressant properties of 5-HT7 receptor antagonists have been widely demonstrated in a large set of animal models. Considering the potential therapeutic advantages in targeting both α2-adrenoceptors and 5-HT7 receptors, we designed a small series of arylsulfonamide derivatives of (dihydrobenzofuranoxy)ethyl piperidines as dually active ligands. Following green chemistry principles, the designed compounds were synthesized entirely using a sustainable mechanochemical approach. The identified compound 8 behaved as a potent α2A/5-HT7 receptor antagonist and displayed moderate-to-high selectivity over α1-adrenoceptor subtypes and selected serotonin and dopaminergic receptors. Finally, compound 8 improved performance of mice in the forced swim test, displaying similar potency to the reference drug mirtazapine. 相似文献
138.
Christiansen SC Hedin N Epping JD Janicke MT del Amo Y Demarest M Brzezinski M Chmelka BF 《Solid state nuclear magnetic resonance》2006,29(1-3):170-182
The robustness and sensitivities of different polarization-transfer methods that exploit heteronuclear dipole-dipole couplings are compared for a series of heterogeneous solid systems, including polycrystalline tetrakis(trimethylsilyl)silane (TKS), adamantane, a physical mixture of doubly (13)C,(15)N-enriched and singly (13)C-enriched polycrystalline glycine, and a powder sample of siliceous marine diatoms, Thalossiosira pseudonana. The methods were analyzed according to their respective frequency-matching spectra or resultant signal intensities. For a series of (13)C{(1)H} cross-polarization experiments, adiabatic passage Hartmann-Hahn cross-polarization (APHH-CP) was shown to have several advantages over other methods, including Hartmann-Hahn cross-polarization (HHCP), variable-amplitude cross-polarization (VACP), and ramped-amplitude cross-polarization (RACP). For X-Y systems, such as (13)C{(15)N}, high and comparable sensitivities were obtained by using APHH-CP with Lee-Goldburg decoupling or by using the transferred-echo double resonance (TEDOR) experiment. The findings were applied to multinuclear (1)H, (13)C, (15)N, and (29)Si CP MAS characterization of a powder diatom sample, a challenging inorganic-organic hybrid solid that places high demands on NMR signal sensitivity. 相似文献
139.
Nebeluk Robert Zarzycki Krzysztof Seredyński Dawid Chaber Patryk Figat Maksym Domański Paweł D. Zieliński Cezary 《Nonlinear dynamics》2023,111(9):8383-8395
Nonlinear Dynamics - Moving-object tracking using a pan–tilt camera setup is quite a well-known task in robotics. However, the presented research addresses specific properties of the tracked... 相似文献
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