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991.
992.
Marilena Vlachou Angeliki-Sofia Foscolos Angeliki Siamidi Angeliki Syriopoulou Nikitas Georgiou Aikaterini Dedeloudi Antonis D. Tsiailanis Andreas G. Tzakos Thomas Mavromoustakos Ioannis P. Papanastasiou 《Molecules (Basel, Switzerland)》2022,27(1)
The aqueous dissolution profile of the isomeric synthetic adamantane phenylalkylamine hydrochlorides I and II was probed. These adducts have shown significant antiproliferative/anticancer activity associated with an analgesic profile against neuropathic pain. They are both devoid of toxic effects and show appreciable enzymatic human plasma stability. The structures of these two compounds have been elucidated using 2D NMR experiments, which were used to study their predominant conformations. Compound II’s scaffold appeared more flexible, as shown by the NOE spatial interactions between the alkyl bridge chain, the aromatic rings, and the adamantane nucleus. Conversely, compound I appeared very rigid, as it did not share significant NOEs between the aforementioned structural segments. MD simulations confirmed the NOE results. The aqueous dissolution profile of both molecules fits well with their minimum energy conformers’ features, which stem from the NOE data; this was nicely demonstrated, especially in the case of compound II. 相似文献
993.
The aim of this study was to investigate binding interactions between β-lactoglobulin (BLG) and two different mucins, bovine submaxillary mucins (BSM) and porcine gastric mucin (PGM), using intrinsic and extrinsic fluorescence spectroscopies. Intrinsic fluorescence spectra showed an enhanced decrease of fluorescence intensity of BLG at all pH conditions when BLG was mixed with PGM rather than with BSM. We propose that, unlike BSM, the tertiary structure of PGM changes and the hydrophobic regions are exposed at pH 3 due to protonation of negatively charged residues. Results suggest that PGM also facilitated the structural unfolding of BLG and its binding with PGM by a hydrophobic interaction, especially at acidic pH, which was further supported by extrinsic fluorescence spectroscopy. Hydrophobic interaction is suggested as the dominant interaction mechanism between BLG and PGM at pH 3, whereas electrostatic interaction is the dominant one between BLG and BSM. 相似文献
994.
Selin Pıravadılı Mucur Daniel Lenkeit Ioannis Kanelidis Sait Eren San Elisabeth Holder Emine Tekin 《Journal of Polymer Science.Polymer Physics》2014,52(2):147-156
An alternating triarylamine‐functionalized fluorene‐based copolymer synthesized using a Suzuki–Miyaura cross‐coupling procedure is used as blue emitting layer in polymer light‐emitting diodes (PLEDs). Subsequently, the effects of CdSe/ZnS quantum dots (QDs) on the optoelectronic properties of the copolymer are investigated. Therefore, CdSe/ZnS QDs are embedded into the copolymer matrix and hybrid PLEDs are fabricated. The devices comprised of CdSe/ZnS QDs reveal enhanced performances, yielding about 3.4 times more luminous efficiency than that of the device without QDs. Further enhancement is achieved by using electron transport layer; the luminous efficiency rose from 0.065 to 1.740 cd A?1 for the hybrid PLEDs, corresponding to a superb 27‐fold intensification of the efficiency. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2014 , 52, 147–156 相似文献
995.
The error behavior of exponential operator splitting methods for nonlinear Schrödinger equations in the semiclassical regime is studied. For the Lie and Strang splitting methods, the exact form of the local error is determined and the dependence on the semiclassical parameter is identified. This is enabled within a defect-based framework which also suggests asymptotically correct a posteriori local error estimators as the basis for adaptive time stepsize selection. Numerical examples substantiate and complement the theoretical investigations. 相似文献
996.
George Costakis Antonios Manoussos Ioannis Parissis 《Complex Analysis and Operator Theory》2014,8(8):1601-1643
We study the notion of recurrence and some of its variations for linear operators acting on Banach spaces. We characterize recurrence for several classes of linear operators such as weighted shifts, composition operators and multiplication operators on classical Banach spaces. We show that on separable complex Hilbert spaces the study of recurrent operators reduces, in many cases, to the study of unitary operators. Finally, we study the notion of product recurrence and state some relevant open questions. 相似文献
997.
998.
999.
Synthesis and characterization of chiral poly(l‐lactide‐b‐hexyl isocyanate) macromonomers with norbornenyl end groups and their homopolymerization through ring opening metathesis polymerization to afford polymer brushes
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Ioannis Choinopoulos Spyros Koinis Marinos Pitsikalis 《Journal of polymer science. Part A, Polymer chemistry》2017,55(6):1102-1112
We report the synthesis of the novel half‐titanocene alkoxide complex bischloro‐η5‐cyclopentadienyl(bicyclo[2.2.1]‐hept‐5‐en‐2‐oxy) titanium (IV), [CpTiCl2(O‐NBE)]. This complex was employed for the synthesis of chiral poly(l ‐lactide‐b‐hexyl isocyanate) diblock copolymer bearing a norbornene end group with sequential addition of monomers. The poly(hexyl isocyanate) block is chiral due to the last l ‐lactide unit of the poly(l ‐lactide) block. This macromonomer was polymerized towards a chiral polymer brush structure with polynorbornene backbone and chiral poly(l ‐lactide‐b‐hexyl isocyanate) side chains using Grubbs first‐generation catalyst. The polymers were characterized using size exclusion chromatography (SEC), nuclear magnetic resonance (NMR), and circular dichroism (CD) spectroscopy and their thermal properties were investigated by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) analysis. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017 , 55, 1102–1112 相似文献
1000.
Ioannis Papageorgiou 《Potential Analysis》2011,35(3):275-286
A criterion is presented for the Modified Logarithmic Sobolev inequality on metric measure spaces. The criterion based on
U-bound inequalities introduced by Hebisch and Zegarlinski allows to show the inequality for measures that go beyond log-concavity. 相似文献