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71.
Cardiac failure has a big impact on the daily life of patients and this can be evaluated using quality of life questionnaires. The aim of this study was to translate and adapt for the French population and test the validity of two quality of life self-administered-questionnaires: the Duke health Profile, the Minnesota Quality of Life Questionnaire in Cardiac Failure and one function capacity questionnaire, the Goldman Specific Activity Scale. The questionnaires were translated and retranslated then submitted to a committee of experts: the final version was presented to 30 patients. The study of the quantitative properties of the three instruments was performed on a sample of 74 patients with cardiac failure to assess their validity and 26 stable patients after cardiac transplantation to test reproducibility. The results of this study show that these three instruments are valid and reproducible and are comparable to the original documents: Cronbach's Alpha ranging from 0.54 to 0.78 for the Duke, except for the social dimension, and from 0.73 to 0.93 for the Minnesota, except for its incapacity dimension, intraclass correlation coefficient > 0.6 in all dimensions. The validity of convergence with LVEF and the NYHA measured during hospitalisation for decompensation was poor, except for the Goldman. The three instruments provided coherent information. The authors conclude that a structured method allows transcultural adaptation of instruments of evaluation of quality of life, the French version having comparable properties to the original documents: they may be used for clinical research.  相似文献   
72.
73.
Production of initial and mechanically alloyed powders of oxide-dispersion-strengthened (ODS) 12Kh13M2FBR (EP-450) reactor stainless steel are considered. Structures of powders and compacted materials have been studied. The rate of thermal creep of the mechanically alloyed EP-450 ODS steel in comparison with the conventional EP-450 steel was estimated.  相似文献   
74.
Glass transition temperatures of polymers were modelled by means of the CORAL software available on the Internet (http://www.insilico.eu/coral). The architecture of monomers was represented via simplified molecular input line entry systems (SMILES). Three random splits into the training and validation sets were tested to build up quantitative structure - property relationships (QSPRs). The index of Ideality of Correlation (IIC) represents a new measure of predictive potential. Application of the IIC as the criterion of predictive potential for the calibration set was tested in this work and resulted in correct recommendations for selection of the best model from three different models considered here.  相似文献   
75.
Microsystem Technologies - The model of fractional magneto-thermoelasticity is applied to one-dimensional problems of a thermoelectric spherical shell subjected to an arbitrary thermal loading of...  相似文献   
76.
Conclusions It has been established that the use of 0.05–0.5% by weight of ferrocene, 1,1-diethylferrocene, or iron (III) acetylacetonate as a fuel additive will reduce carbon emission by 50–60%.Translated from Khimiya i Tekhnologiya Topliv i Masel, No. 3, pp. 40–41, March, 1975.  相似文献   
77.
Using rice straw, bagasse, and cotton stalk fibers as reinforcing fillers in polyester composite was studied. The effects of fiber loading and fiber size on the modulus of rupture (MOR), modulus of elasticity (MOE), tensile strength, water absorption, and thickness swelling were investigated as well. The effect of esterification using maleic anhydride on the aforementioned properties also was studied. Ultraviolet light resistance and thermal behavior of the produced composites were also investigated. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 87: 653–660, 2003  相似文献   
78.
This article presents a comprehensive study of disturbances of the temperature regime of the Earth’s stratosphere, which are related to sudden stratospheric warmings over Western and Eastern Siberia and the Russian Far East in the winters of 2008–2012. This study is based on data obtained using temperature remote-sensing techniques (lidar and satellite ones). The analysis rests on data on vertical temperature distribution in the stratosphere, obtained from lidar measurements over regions of Tomsk (56°N, 85°E), Yakutsk (61°N, 130°E), and Paratunka, the Kamchatka territory (53°N, 158°E). For complex analysis of the spatial–temporal temperature distribution in the middle atmosphere, the lidar measurement data are applied along with satellite data on temperature acquired by the microwave limb sounder on the Earth Observing System Aura satellite. We consider the regional effects of sudden stratospheric warmings that were observed over the Asian region of Russia (~85–160°E) in the winters of 2008–2012. There were stratospheric warmings over the Asian region of Russia each winter during the period under consideration, as deduced from lidar and satellite measurements of temperature. Lidar and satellite measurements of temperature have evidenced the previously known peculiarities of the development of winter stratospheric warmings. On the whole, lidar and satellite measurements of height distribution of temperatures agree. Possible reasons for the divergences under consideration are discussed.  相似文献   
79.
Copolymer hydrogels were prepared through the γ irradiation of aqueous solutions composed of different ratios of acrylamide (AAm) and vinyl pyrrolidone (VP) monomers. The chemical structure, thermal stability, and structural morphology of the hydrogels were characterized with Fourier transform infrared spectroscopy, thermogravimetric analysis (TGA), and scanning electron microscopy, respectively. The IR spectroscopy analysis showed the formation of copolymerization and the presence of hydrogen bonding. The TGA study showed that the AAm/VP‐based hydrogels possessed higher thermal stability than polyacrylamide (PAAm). However, the thermal stability of the AAm/VP hydrogels increased with an increasing ratio of the VP component. The study of the swelling kinetics in water showed that all the hydrogels reached the equilibrium state after 24 h. However, the AAm/VP‐based hydrogels showed swelling in water that was lower than that of the hydrogel based on pure AAm. Meanwhile, the degree of swelling of the AAm/VP‐based hydrogels decreased with an increasing ratio of VP in the feeding solutions. The results showed that the PAAm and AAm/VP‐based hydrogels prepared at 50 kGy were affected by a change in the temperature around 25°C, whereas the hydrogels prepared at 25 kGy did not show this characteristic. However, the hydrogels prepared at different doses displayed reversible pH character. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007  相似文献   
80.
Antimicrobial, membranotropic and cytotoxic properties of dicationic imidazolium surfactants of n-s-n (Im) series with variable length of alkyl group (n = 8, 10, 12, 14, 16) and spacer fragment (s = 2, 3, 4) were explored and compared with monocationic analogues. Their activity against a representative range of Gram-positive and Gram-negative bacteria, and also fungi, is characterized. The relationship between the biological activity and the structural features of these compounds is revealed, with the hydrophobicity emphasized as a key factor. Among dicationic surfactants, decyl derivatives showed highest antimicrobial effect, while for monocationic analogues, the maximum activity is observed in the case of tetradecyl tail. The leading compounds are 2–4 times higher in activity compared to reference antibiotics and prove effective against resistant strains. It has been shown that the antimicrobial effect is not associated with the destruction of the cell membrane, but is due to specific interactions of surfactants and cell components. Importantly, they show strong selectivity for microorganism cells while being of low harm to healthy human cells, with a SI ranging from 30 to 100.  相似文献   
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