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941.
Yurii S. Borovikov Daria D. Andreeva Stanislava V. Avrova Vladimir V. Sirenko Armen O. Simonyan Charles S. Redwood Olga E. Karpicheva 《International journal of molecular sciences》2021,22(12)
Point mutations in the genes encoding the skeletal muscle isoforms of tropomyosin can cause a range of muscle diseases. The amino acid substitution of Arg for Pro residue in the 90th position (R90P) in γ-tropomyosin (Tpm3.12) is associated with congenital fiber type disproportion and muscle weakness. The molecular mechanisms underlying muscle dysfunction in this disease remain unclear. Here, we observed that this mutation causes an abnormally high Ca2+-sensitivity of myofilaments in vitro and in muscle fibers. To determine the critical conformational changes that myosin, actin, and tropomyosin undergo during the ATPase cycle and the alterations in these changes caused by R90P replacement in Tpm3.12, we used polarized fluorimetry. It was shown that the R90P mutation inhibits the ability of tropomyosin to shift towards the outer domains of actin, which is accompanied by the almost complete depression of troponin’s ability to switch actin monomers off and to reduce the amount of the myosin heads weakly bound to F-actin at a low Ca2+. These changes in the behavior of tropomyosin and the troponin–tropomyosin complex, as well as in the balance of strongly and weakly bound myosin heads in the ATPase cycle may underlie the occurrence of both abnormally high Ca2+-sensitivity and muscle weakness. BDM, an inhibitor of myosin ATPase activity, and W7, a troponin C antagonist, restore the ability of tropomyosin for Ca2+-dependent movement and the ability of the troponin–tropomyosin complex to switch actin monomers off, demonstrating a weakening of the damaging effect of the R90P mutation on muscle contractility. 相似文献
942.
Rodriguez J. S. Duran J. F. Aguilar Y. Alcazar G. A. Perez Souza R. M. Zambrano O. A. 《Metallurgical and Materials Transactions A》2022,53(8):2961-2976
Metallurgical and Materials Transactions A - In the present work, the dynamic recrystallization and microstructural evolution of the family of advanced high-strength steels Fe18MnxAl0.74C are... 相似文献
943.
Grigoriev O.N. Panasyuk A.D. Brodnikovskyy M.P. Podchernyaeva I.O. Melakh L.M. Yurechko D.V. Vedel D.V. Kozak I.V. 《Powder Metallurgy and Metal Ceramics》2022,60(9-10):626-634
Powder Metallurgy and Metal Ceramics - Hot pressing was used to produce compact ceramic samples with the following composition (wt.%): 60 ZrB2 + 20 SiC + 20 (Al2O3 + 32 t-ZrO2). The tetragonal... 相似文献
944.
Rudenko A. V. Kataev A. A. Tkacheva O. Yu. Zaikov Yu. P. Pianykh A. A. Arkhipov G. V. 《Russian Journal of Non-Ferrous Metals》2022,63(1):1-6
Russian Journal of Non-Ferrous Metals - Viscosity of conventional cryolite-alumina melts NaF–AlF3–CaF2–Al2O3 with a cryolite ratio (xNaF/xAlF3, mol/mol) 2.3 was studied in... 相似文献
945.
Turchanin M.A. Dreval L.O. Agraval P.G. Korsun V.A. Vodopyanova A.O. 《Powder Metallurgy and Metal Ceramics》2022,60(11-12):727-737
Powder Metallurgy and Metal Ceramics - The thermodynamic properties of liquid alloys in glass-forming systems were described in the framework of the associated solution model (ASM) according to the... 相似文献
946.
Rutskii D. V. Morozov V. V. Zyuban N. A. Kirilichev M. V. Nikititin M. S. Voitenko R. M. Kharlamov V. O. 《Metallurgist》2022,66(5-6):544-556
Metallurgist - Results are provided for a study showing the effect of Ca- and Ba-containing master alloys on composition and contamination with non-metallic inclusions during extra-furnace... 相似文献
947.
Sivtsov A. V. Egiazar’yan D. K. Sheshukov O. Yu. Tsimbalist M. M. Orlov P. P. Mikheenkov M. A. 《Metallurgist》2022,66(1-2):11-18
Metallurgist - A method for controlling dynamic current-voltage characteristics in an electric arc furnace is described. The influence of the electrode’s current direct component on the... 相似文献
948.
Anodic reactions at the CO, CO2|Ni electrode in molten sodium carbonate at 1000°C are examined in detail. Experimental polarization curves are fitted via a computer graphics procedure to a model employing five anodic reactions with activation, concentration and resistance polarization, and passivation. The resultant empirical parameters are interpreted in terms of absolute rate expressions describing possible anodic reactions. Three of the anodic reactions are found to be in accord with the findings at inert electrodes by previous investigators, i.e. oxidation of CO by two mechanisms and oxidation of carbonate, while the cathodic reaction is consistent with reduction of CO2. The remaining two anodic reactions were associated with the oxidation of nickel to Ni2+ with formation of a NiO film above a passivation potential, and, at higher anodic overpotentials, oxidation of NiO to a higher oxide, e.g. Ni2O3. There is an indication of the formation of a third oxide at still higher anodic overpotentials. 相似文献
949.
O. V. Goslavskii A. G. Derzhavin I. N. Shcherbinin 《Metal Science and Heat Treatment》1989,31(11):822-825
1. | Maraging steel 05Kh13N7D2 with a different degree of strengthening exhibits quite high impact strength. With an increase in aging temperature from 450 to 600°C the impact strength a0.25 increases from 49 to 118 J/cm2. |
2. | Prolonged soaking at 300°C leads to the embrittlement of steel aged at 550°C for 10 h. The critical brittleness temperature T50 is –80°C in the original condition and it remains practically unchanged. |
3. | Fracture toughness KIC and critical crack opening c for steel 05Kh13N7D2 are at quite a high level at temperatures to –125°C. |
950.
Quasi-isotropic. laminates have isotropic elastic properties in all in-plane directions. Therefore, this kind of laminate is widely used for structural elements. The simplest stacking sequence of quasi-isotropic laminates is [0/-60/60]s. When the direction of applied axial load to [0/-60/60]s laminate is inclined at a 30-degree angle, we have the other quasi-isotropic laminate [30/-30/90]s under axial load. The failure mechanisms of these two laminates are, however, entirely different from each other because these two laminates have different distribution of the interlaminar stresses. It was confirmed by tensile fatigue tests that the [0/-60/60]s laminate does not show any visible fatigue damage, but the [30/-30/90]s laminate develops edge-delamination during cyclic loading. The analytical results were in good agreement with the experimental results. 相似文献