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101.
Pavel Seredin Dmitry Goloshchapov Yuri Ippolitov Jitraporn Vongsvivut 《International journal of molecular sciences》2021,22(12)
The aim of this work is to develop a biomimetic interface between the natural tooth tissue and the restorative composite and to study it on the basis of synchrotron micro-FTIR mapping and multidimensional processing of the spectral data array. Using hierarchical cluster analysis of 3D FTIR data revealed marked improvements in the formation of the dentine/adhesive/dental hybrid interface using a biomimetic approach. The use of a biomimetic strategy (application of an amino acid–modified primer, alkaline calcium and a nano-c-HAp–modified adhesive) allowed the formation of a matrix that can be structurally integrated with natural dentine and dental composite. The biomimetic hybrid layer was characterised by homogeneous chemical composition and a higher degree of conversion of the adhesive during polymerisation, which should provide optimal integration of the dental composite with the dentine. 相似文献
102.
Akira Kaieda Dr. Masashi Takahashi Hiromi Fukuda Dr. Rei Okamoto Dr. Shinji Morimoto Masayuki Gotoh Takahiro Miyazaki Yuri Hori Satoko Unno Dr. Tomohiro Kawamoto Dr. Toshimasa Tanaka Dr. Sachiko Itono Terufumi Takagi Dr. Hiroshi Sugimoto Dr. Kengo Okada Dr. Weston Lane Dr. Bi-Ching Sang Dr. Kumar Saikatendu Dr. Shinichiro Matsunaga Dr. Seiji Miwatashi 《ChemMedChem》2019,14(24):2093-2101
We identified novel potent inhibitors of p38 mitogen-activated protein (MAP) kinase using a structure-based design strategy, beginning with lead compound, 3-(butan-2-yl)-6-(2,4-difluoroanilino)-1,3-dihydro-2H-imidazo[4,5-b]pyridin-2-one ( 1 ). To enhance the inhibitory activity of 1 against production of tumor necrosis factor-α (TNF-α) in human whole blood (hWB) cell assays, we designed and synthesized hybrid compounds in which the imidazo[4,5-b]pyridin-2-one core was successfully linked with the p-methylbenzamide fragment. Among the compounds evaluated, 3-(3-tert-butyl-2-oxo-2,3-dihydro-1H-imidazo[4,5-b]pyridin-6-yl)-4-methyl-N-(1-methyl-1H-pyrazol-3-yl)benzamide ( 25 ) exhibited potent p38 inhibition, superior suppression of TNF-α production in hWB cells, and also significant in vivo efficacy in a rat model of collagen-induced arthritis (CIA). In this paper, we report the discovery of potent, selective, and orally bioavailable imidazo[4,5-b]pyridin-2-one-based p38 MAP kinase inhibitors. 相似文献
103.
Kazuko Iwamoto Shinichi Matsumura Yuri Yoshioka Ayami Yamamoto Shohei Makino Tatsuya Moriyama Nobuhiro Zaima 《Lipids》2019,54(5):311-320
Accumulation of amyloid-β peptide is associated with Alzheimer's dementia. Previously, we reported that sesamin and sesamolin inhibited β-secretase activity in vitro, and each was transported to the serum and brain in mice after oral administration. However, the bioavailability of sesamin and sesamolin was poor in mice. In this study, we aimed to improve the bioavailability of sesamin and sesamolin. We found that the levels of sesamin and sesamolin in mouse serum and brain were higher after the administration of a mixture of sesame extract and turmeric oil (MST) than those after administering sesame extract alone. Serum sesamin and sesamolin contents in the MST-treated group were 23-fold and 15-fold higher, respectively, than those in the sesame extract-treated group. Brain sesamin and sesamolin contents in the MST-treated group were 14-fold and 11-fold higher, respectively, than those in the sesame extract-treated group. These results suggest that turmeric oil is an effective solvent to enhance the bioavailability of sesamin and sesamolin. 相似文献
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107.
Yuri S. Lipatov Tatiana T. Alekseeva Lyubov A. Sorochinskaya Galina V. Dudarenko 《Polymer Bulletin》2008,59(6):739-747
Summary Peculiarities of formation kinetics of sequential semi-interpenetrating polymer networks based on crosslinked polyurethane
with different cross-linking density and linear polystyrene and polybutylmethacrylate have been studied. Polyurethane networks
were synthesized differing in molecular mass Mc of the chains between cross-links. Monomeric styrene and butyl methacrylate were introduced into these networks by swelling
them in monomers up to equilibrium. The kinetics of polymerization of monomers in swollen networks was investigated. The experimental
data show the dependence of the kinetic parameters of polymerization on Mc, this dependence being different for various monomers. Sharp discrepancy in molecular mass distribution of polymers formed
in various matrices has been observed. The differences in dependencies of reaction kinetics and molecular mass distribution
are supposed to be connected to various dependence of the chain growth and termination of various monomers on the density
of network, i.e. on the confinements imposed by the intranetwork space. 相似文献
108.
Generating vegetation leaf area index earth system data record from multiple sensors. Part 1: Theory
Sangram Ganguly Mitchell A. Schull Arindam Samanta Nikolay V. Shabanov Cristina Milesi Ramakrishna R. Nemani Yuri Knyazikhin Ranga B. Myneni 《Remote sensing of environment》2008,112(12):4333-4343
The generation of multi-decade long Earth System Data Records (ESDRs) of Leaf Area Index (LAI) and Fraction of Photosynthetically Active Radiation absorbed by vegetation (FPAR) from remote sensing measurements of multiple sensors is key to monitoring long-term changes in vegetation due to natural and anthropogenic influences. Challenges in developing such ESDRs include problems in remote sensing science (modeling of variability in global vegetation, scaling, atmospheric correction) and sensor hardware (differences in spatial resolution, spectral bands, calibration, and information content). In this paper, we develop a physically based approach for deriving LAI and FPAR products from the Advanced Very High Resolution Radiometer (AVHRR) data that are of comparable quality to the Moderate resolution Imaging Spectroradiometer (MODIS) LAI and FPAR products, thus realizing the objective of producing a long (multi-decadal) time series of these products. The approach is based on the radiative transfer theory of canopy spectral invariants which facilitates parameterization of the canopy spectral bidirectional reflectance factor (BRF). The methodology permits decoupling of the structural and radiometric components and obeys the energy conservation law. The approach is applicable to any optical sensor, however, it requires selection of sensor-specific values of configurable parameters, namely, the single scattering albedo and data uncertainty. According to the theory of spectral invariants, the single scattering albedo is a function of the spatial scale, and thus, accounts for the variation in BRF with sensor spatial resolution. Likewise, the single scattering albedo accounts for the variation in spectral BRF with sensor bandwidths. The second adjustable parameter is data uncertainty, which accounts for varying information content of the remote sensing measurements, i.e., Normalized Difference Vegetation Index (NDVI, low information content), vs. spectral BRF (higher information content). Implementation of this approach indicates good consistency in LAI values retrieved from NDVI (AVHRR-mode) and spectral BRF (MODIS-mode). Specific details of the implementation and evaluation of the derived products are detailed in the second part of this two-paper series. 相似文献
109.
Sung-Tae Hong Yuri Hovanski Curt A. Lavender K. Scott Weil 《Journal of Materials Engineering and Performance》2008,17(3):382-386
The die stress profiles during compaction of commercially pure titanium (Ti) and commercial lubricated iron (Fe) powders were
experimentally investigated using an instrumented die. The die was designed to simulate double-action pressing, and a detailed
stress profile was measured along the height of the die using multiple custom-made strain gage pins. The stress history shows
that residual stress remained in the die in the radial direction after the axial compaction stress was removed from the powder.
Also, the stress profile at the maximum axial stress and the residual stress profile were observed to be symmetric across
the height of the compact for both powders, but both have a unique shape for each powder. For both the stress profile at the
maximum axial stress and the residual stress profile, the unlubricated Ti powder produced a much higher radial stress at the
center of the compact with a steep pressure gradient on both top and bottom of the compact, while the lubricated Fe powder
produced a rather uniform radial stress distribution along the height of the compact.
This article was presented at Materials Science & Technology 2007, Automotive and Ground Vehicles symposium held September
16–20, 2007, in Detroit, MI. 相似文献
110.
Vladislav Dushin Valeriy Nikitin Yuri Philippov Nickolay Smirnov 《Microgravity science and technology》2008,20(3-4):155-160
The paper presents the results of investigating the instability of the displacement of viscous fluid by a less viscous one in two-dimensional and three-dimensional porous specimens. The effects of the three-dimensional phenomena on development of instability are revealed, in particular, the faster growth of 3D disturbances as compared with 2D ones, while 2D displacement integral parameters (such as the outflow of the displacing fluid) have much higher deviations than those parameters obtained in 3D modelling. This can be explained by much higher number of fingers in 3D cases of displacement reaching the outflow surface, and by the subsequent compensation of disturbances in the overall outflow. 相似文献