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排序方式: 共有1001条查询结果,搜索用时 15 毫秒
921.
Izabela Neska-Dugosz Karolina Buchholz Justyna Durlewicz Maciej Gagat Dariusz Grzanka Krzysztof Tojek Anna Klimaszewska-Winiewska 《International journal of molecular sciences》2021,22(18)
Genomic instability (GIN) has an important contribution to the pathology of colorectal cancer (CRC). Therefore, we selected mitosis and cytokinesis kinesins, KIF11 and KIF14, as factors of potential clinical and functional value in CRC, as their aberrant expression has been suspected to underlie GIN. We examined the expression and the prognostic and biological significance of KIF11 and KIF14 in CRC via in-house immunohistochemistry on tissue microarrays, public mRNA expression datasets, as well as bioinformatics tools. We found that KIF11 and KIF14 expression, at both the protein and mRNA level, was markedly altered in cancer tissues compared to respective controls, which was reflected in the clinical outcome of CRC patients. Specifically, we provide the first evidence that KIF11 protein and mRNA, KIF14 mRNA, as well as both proteins together, can significantly discriminate between CRC patients with better and worse overall survival independently of other relevant clinical risk factors. The negative prognostic factors for OS were high KIF11 protein, high KIF11 protein + low KIF14 protein, low KIF11 mRNA and low KIF14 mRNA. Functional enrichment analysis revealed that the gene sets related to the cell cycle, DNA replication, DNA repair and recombination, among others, were positively associated with KIF11 or KIF14 expression in CRC tissues. In TCGA cohort, the positive correlations between several measures related to GIN and the expression of KIFs were also demonstrated. In conclusion, our results suggest that CRC patients can be stratified into distinct risk categories by biological and molecular determinants, such as KIF11 and KIF14 expression and, mechanistically, this is likely attributable to their role in maintaining genome integrity. 相似文献
922.
Information about the mobility and the partitioning properties of brominated persistent organic pollutants, the environmental levels of which are sometimes higher than those of the chlorinated analogues, is limited. We estimated n-octanol/ water (log K(OW)), n-octanol/air (log K(OA)), and air/water (log K(AW)) partition coefficients for 1436 chloro- and bromo-analogues of dibenzo-p-dioxins, dibenzofurans, biphenyls, naphthalenes, diphenyl ethers, and benzenes by employing quantitative structure-property relationship (QSPR) techniques. The searches for similar partitioning patterns were performed by means of two-dimensional cluster analysis. Five classes of compounds were identified. Each of the class is characterized by similar partition coefficients and, in consequence, similar environmental properties. Finally the data was fitted into a simple multimedia model involving the partitioning map. In addition, we found thatthe changes in the partition coefficients upon the replacement of chlorine with bromine were constant: 0.11, 0.31, and -0.21 per bromine atom for log K(OW), log K(OA), and log K(AW), respectively. On the basis of this observation, a method for rapid estimation of changes in the partition coefficient upon chlorine-bromine substitution was proposed. 相似文献
923.
Krzysztof Drozdowicz Urszula WiącekEwa Krynicka Barbara GabańskaUrszula Woźnicka 《Annals of Nuclear Energy》2008
Diffusion cooling of thermal neutron flux in a finite volume of a medium results from the leakage of neutrons. The cooling effect is particularly complex when the system consists of zones with different neutron scattering properties. A study is presented on the diffusion cooling in Plexiglas (hydrogenous material), which constitutes an outer cylindrical shell surrounding an inner cylinder made of a non-hydrogenous substance. The pulsed neutron method has been used. Numerous series of the desired pulsed neutron experiments in two-zone cylindrical systems have been substituted by Monte Carlo simulations. The decay constant of the fundamental mode in the time distribution of the pulsed thermal neutron flux has been determined in each experiment. The so-called theoretical decay constants (defined under a particular assumption) have been calculated as a function of the system geometry and neutron dynamic parameters including the diffusion cooling coefficient of the outer Plexiglas shell. The variability of this parameter has been determined from a combination of experimental and theoretical results. For a system with a theoretical decay constant varying between 12,000 and 34,000 s−1, the diffusion cooling coefficient of Plexiglas in the outer layer varies between 9000 and 4800 cm4 s−1 with the latter being close to the value for homogeneous material. A function has been obtained and successfully applied in interpreting real experiments using Czubek’s method of measuring the absorption cross-section of small samples. 相似文献
924.
Electrochemical impedance spectroscopy technique was used to describe behavior of AB5-type hydrogen storage alloy. Impedance investigations were performed during cyclic voltammetry measurement and charge/discharge cycles. The comprehensive interpretation of instantaneous impedance spectra obtained in potentiostatic mode allowed further to interpret impedance results in galvanostatic mode. Proposed methodology enabled to trace electrical parameters as a function of state of charge (SOC) and depth of discharge (DOD). 相似文献
925.
Methodologies of Compressing a Stable Performance Convolutional Neural Networks in Image Classification 总被引:1,自引:0,他引:1
Al-Hami Mo’taz Pietron Marcin Casas Raul Wielgosz Maciej 《Neural Processing Letters》2020,51(1):105-127
Neural Processing Letters - Deep learning has made a real revolution in the embedded computing environment. Convolutional neural network (CNN) revealed itself as a reliable fit to many emerging... 相似文献
926.
Maciej Nastaj Konrad Terpiłowski Bartosz G. Sołowiej 《International Journal of Food Science & Technology》2020,55(5):2179-2187
The aim of this paper was to investigate the effect of whey protein isolate (WPI) and polymerised whey protein isolate (WPP) addition on physicochemical properties of processed cheese with partial fat replacement. Surface properties were determined by advancing (θa) and receding (θr) contact angles, apparent free surface energy (γs). Roughness measurements, cheese meltability and Turbiscan Stability Index (TSI) were evaluated by Turbiscan. Higher WPP concentrations produced the more hydrophobic surfaces of the samples. Conversely, increase in WPI addition promoted the hydrophilic cheese surfaces. The effect of roughness was much larger for samples containing WPI. The increase in protein addition caused a decrease in meltability and an increase in stability of cheeses. The optical and confocal images have proved that cheeses with WPP demonstrated more packed and denser structure in comparison to samples with WPI. 相似文献
927.
Marcin Pajak Marcin Mozdzierz Maciej Chalusiak Shinji Kimijima Janusz S. Szmyd Grzegorz Brus 《International Journal of Hydrogen Energy》2018,43(45):20474-20487
The presented paper focuses on a numerical analysis of a heat and mass transfer process in a novel type of methane/steam reforming reactor. The novelty of the macro-patterned reactor design lies in dividing a reformer into segments of various lengths and reactivity. Precisely, splitting the catalyst and filling the created empty volume with porous, non-reactive, thermal conducting material such as metallic foam. This approach allows for moderating a sharp temperature drop at the inlet of the reactor typical for the endothermic methane/steam reforming process. To analyze the considered system, the mathematical and numerical models of transport phenomena and the reaction kinetics were developed and implemented into an in-house solver. The kinetics of methane/steam reforming was taken from the literature. The outlet composition obtained from the kinetic model was compared with the experimental measurements and good agreement was found. The conducted numerical analysis includes cases that differ from a number and lengths of catalytic and non-catalytic segments. The obtained results indicate that the macro-patterned design is a promising strategy that allows for a significant improvement of temperature distribution in a reforming reactor. It was shown that the proposed approach could help to cut the cost of the catalyst material by allowing for the conversion of methane with a smaller amount of the catalyst close to the reference case. 相似文献
928.
929.
半导体磁光理论和红外磁光光谱研究进展 总被引:1,自引:0,他引:1
本文主要报告我们近几年在发展磁光光谱实验技术、研制红外磁光测试系统和通过红外磁光光谱研究HgCdTe、GaAs、Si等半导体的能带结构,杂质缺陷,声子及其它元激发行为等工作中取得的成果,同时对有关理论作一般性介绍。 相似文献
930.
In this work, we investigate the relationship between the rubbery modulus and the degree of cure for partially to fully cured LY5052 epoxy resin. In particular, this paper experimentally tests an existing model formulated for shear modulus by redefining for in the tensile storage modulus. Experiments to characterize viscoelastic behaviour were performed in a dynamic mechanical and thermal analysis (DMTA) instrument in the frequency domain. Master curves are then created from DMTA using general time–temperature–cure superposition. The master curves are then normalized using the model so that the master curve does not depend on the properties in the rubbery region. This results in a unique master curve that describes the viscoelastic behaviour of the LY5052 epoxy resin for the given conditions. Once the relationship between the rubbery modulus and the degree of cure has been established, the amount of experimental characterization can be reduced. This could lead to the development of simplified experimental methodologies and simplified models to characterize the viscoelasticity of low molecular weight resins like the LY5052 epoxy resin system. 相似文献