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131.
132.
Herein, we propose two chalcone molecules, (E)-1-(4-methoxyphenyl)-3-(p-tolyl) prop-2-en-1-one and (E)-3-(4-hydroxyphenyl)-1-(2,4,6-trihydroxyphenyl) prop-2-en-1-one, based on the anticancer bioactive molecule Xanthohumol, which are suitable for further in vitro and in vivo studies. Their ability to create stable complexes with the antiapoptotic X-linked IAP (XIAP) protein makes them promising anticancer agents. The calculations were based on ligand-based and structure-based virtual screening combined with the pharmacophore build. Additionally, the structures passed Lipinski’s rule for drug use, and their reactivity was confirmed using density functional theory studies. ADMET studies were also performed to reveal the pharmacokinetic potential of the compounds. The candidates were chosen from 10,639,400 compounds, and the docking protocols were evaluated using molecular dynamics simulations. 相似文献
133.
Natasa P. Kalogiouri Christina Karadimou Mary S. Avgidou Elissavet Petsa Emmanouil-Nikolaos Papadakis Serafeim Theocharis Ioannis Mourtzinos Urania Menkissoglu-Spiroudi Stefanos Koundouras 《Molecules (Basel, Switzerland)》2022,27(20)
A rapid and simple HPLC-DAD analytical method was developed and optimized for the determination of anthocynanins in three red Greek winegrape varieties (Kotsifali, Limnio, and Vradiano). The critical parameters, such as the acidifying solvent and the extraction temperature, which affect the extraction of anthocyanins from the grapes, were studied to find the optimum values. The developed methodology was validated in terms of selectivity, linearity, accuracy, and precision and presented satisfactory results. The limits of quantification (LOQs) ranged between 0.20 mg/kg to 0.60 mg/kg, and the limits of detection (LODs) ranged between 0.06 mg/kg and 0.12 mg/kg. The RSD% of the within-day and between-day assays were lower than 6.2% and 8.5%, respectively, showing adequate precision. The accuracy ranged between 91.6 and 119% for within-day assay and between 89.9 and 123% for between-day assay. Sixteen samples from the main regions of each variety as well as from the official ampelographic collections of Greece were collected during the 2020 growing season and were further analyzed by HPLC-DAD. Notable differences in the anthocyanin content were detected among the cultivars using hierarchical cluster analysis (HCA). 相似文献
134.
Christine M. Papadakis Kristoffer Almdal Kell Mortensen Frank Rittig Petr tpnek 《Macromolecular Symposia》2000,162(1):275-290
We report on polarized and depolarized dynamic light scattering (DLS) measurements on two asymmetric poly(ethylene‐alt‐propylene‐block‐dimethylsiloxane) (PEP‐PDMS) diblock copolymers in bulk. Apart from the disordered phase, the samples form various ordered morphologies below their respective order‐to‐disorder transition temperatures: One of the samples forms the hexagonal structure composed of PEP cylinders in a PDMS matrix, whereas the other one forms three ordered structures as a function of temperature, among them two cubic micellar structures and a non‐cubic structure. We report here on the dynamic processes found in polarized DLS measurements in the disordered, hexagonal, cubic micellar and non‐cubic structure in the same material. 相似文献
135.
I. Papadakis Christophe R. Quétel Philip D. P. Taylor Paul De Bièvre 《Accreditation and quality assurance》2000,5(5):198-204
Metrological certification through a primary method of measurement and how it can be achieved is demonstrated in this paper,
using the example of re-certification of cadmium and lead content in a biological material, the Bureau Communataire de Reference,
reference material CRM-278R mussel tissue. The measurement method used was isotope dilution in combination with inductively
coupled plasma mass spectrometry. Microwave digestion was applied to the samples prior to the measurements. A detailed uncertainty
budget was evaluated according to the International Organisation of Standardisation, Guide to the Expression of Uncertainty
and EURACHEM Guide, resulting in an expanded uncertainty.
Received: 20 August 1999 / Accepted: 3 January 2000 相似文献
136.
137.
138.
Stavros Argyrios Papadakis 《代数通讯》2013,41(1):313-321
In this note we deal with rational curves in ? 3 which are images of a line by means of a finite sequence of cubo-cubic Cremona transformations. We prove that these curves can always be obtained applying to the line a sequence of such transformations increasing at each step the degree of the curve. As a corollary we get a result about curves that can give speciality for linear systems of ? 3. 相似文献
139.
Raffaello Papadakis Ioanna Deligkiozi Athanase Tsolomitis 《Analytical and bioanalytical chemistry》2010,397(6):2253-2259
This work deals with the design, synthesis, and characterization of a new solvatochromic dye. The intense solvatochromic behavior
of this new synthesized non symmetric viologen was investigated using UV–Vis spectrophotometry. A further purpose was the
study of the interactions between the solvent and solute molecules responsible for the solvatochromism. Several protic and
aprotic solvents were used, and the resulting absorption maxima wavenumbers obtained via UV–Vis spectrophotometry, were correlated
with the solvent polarity parameters, E
T
(30) (Dimroth–Reichardt solvent polarity parameter) and the Gutmann’s donor number (DN) using the biparametric model introduced
by Krygowski and Fawcett. The analysis of the relative contribution of each parameter has clearly shown that the dominating
interaction responsible for the solvatochromic behavior observed is the proton donation by the solute molecules to the solvent
molecules, the latter acting as a Lewis bases. This is an interaction which can be described by DN. Additionally, the good
correlation with the Kamlet–Taft parameter β is in good agreement. 相似文献
140.
Papadakis CM Rittig F Almdal K Mortensen K Stĕpánek P 《The European physical journal. E, Soft matter》2004,15(4):359-370
The structure and dynamics of a strongly asymmetric poly(ethylene propylene)-poly(dimethylsiloxane) (PEP-PDMS) diblock copolymer in the melt have been studied over a wide temperature range. Small-angle neutron scattering reveals that the sample exhibits two stable phases in this temperature range: Above the order-to-disorder transition temperature, it is disordered, whereas the domain structure is body-centered cubic (bcc) below, being stable down to the lowest temperatures measured. In the disordered state, dynamic light scattering (DLS) in the polarized geometry reveals the heterogeneity mode and the cluster mode. In the bcc phase, the PEP and the PDMS blocks form the micellar cores and the matrix, respectively. Here, two modes are observed in DLS, and the diffusion coefficients measured using pulsed field gradient (PFG) NMR are broadly distributed with the most probable diffusion coefficient coinciding with the slow DLS mode. We attribute the fast process in the bcc state to concentration fluctuations of the micellar cores (PEP), relaxing by mutual diffusion of the micelles with copolymers dissolved in the PDMS matrix. The slower process in the bcc state is ascribed to activated long-range self-diffusion of single copolymers from micelle to micelle through the PDMS matrix. This assignment is corroborated by the good coincidence of the reduced diffusivities with the ones from the literature. However, this mode may also be assigned to the rearrangement of entire micelles.This paper is dedicated to the memory of G. Fleischer 相似文献