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91.
Typical non-metallic inclusions in two industrial low-carbon steels for oil pipelines were investigated as three-dimensional objects on film filters after electrolytic extraction and filtration of metal samples. A method of soft chemical extraction using a 10%AA electrolyte was used to study the initial corrosion process in the steel matrix surrounding various non-metallic inclusions. To determine and compare “corrosive” inclusions and their influence on the initial stages of corrosion of the adjacent layer of the steel matrix, quantitative parameters (such as the diameter of the corrosion crater (Dcr) and pit (Dpit), and the relative dissolution coefficient of the metal matrix (KD) around various inclusions) were determined after chemical extraction. It was found that CaO-Al2O3-MgO oxides and TiN inclusions did not cause an initial corrosion of the steel matrix surrounding these inclusions. However, tensile stresses in the steel matrix occurred around CaS inclusions (or complex inclusions containing a CaS phase), which contributed to the initiation of corrosion around these inclusions. 相似文献
92.
Adrian M. Dubuc Marc Remke Andrey Korshunov Paul A. Northcott Shing H. Zhan Maria Mendez-Lago Marcel Kool David T. W. Jones Alexander Unterberger A. Sorana Morrissy David Shih John Peacock Vijay Ramaswamy Adi Rolider Xin Wang Hendrik Witt Thomas Hielscher Cynthia Hawkins Rajeev Vibhakar Sidney Croul James T. Rutka William A. Weiss Steven J. M. Jones Charles G. Eberhart Marco A. Marra Stefan M. Pfister Michael D. Taylor 《Acta neuropathologica》2013,125(3):373-384
93.
The present study compared intake of sweet (saccharin), bitter (quinine), and neutral (water) tastants available either in the context of suckling behavior through a surrogate nipple or independent adultlike feeding through an intraoral cheek cannula in 3-hr-old newborn rats lacking any suckling experience and 24-hr-old rats with regular experience with the dam's nipple. The new technique of online monitoring of fluid flow was applied for assessment of the temporal patterns of ingestion. Newborn and 1-day-old rats tested in the context of suckling behavior showed extremely low intake of quinine, moderate intake of water, and high intake of saccharin. In the same way, they demonstrated low intake of quinine and high intake of saccharin in the context of independent feeding, but intake of water was also high and comparable to that of saccharin. Suckling rats attained higher efficacy of fluid extraction from nipple than pups drinking from cannula. The differential responsiveness to quinine, saccharin, and water in suckling rats was also manifested through attachment behavior, with pups spending less time on the nipple providing quinine and more time on the nipple with saccharin than on the nipple providing water. These results suggest that neonates show taste differentiation as early as 3 hr after birth, and that this taste differentiation is more pronounced in the context of suckling behavior than in the context of adultlike, independent ingestion. 相似文献
94.
Olga A. Goncharova Andrey Yu. Luchkin Nina P. Andreeva Vadim E. Kasatkin Sergey. S. Vesely Nikolay N. Andreev Yurii I. Kuznetsov 《Materials》2022,15(4)
It has been shown by a set of corrosion, electrochemical and physical methods that a chamber corrosion inhibitor that consists of a mixture of octadecylamine (ODA) and benzotriazole (BTA) efficiently protects copper and brass from atmospheric corrosion and can be used for the temporary protection of metal items. The optimum temperatures of treatment with the ODA + BTA mixed inhibitor is 120 °C for brass and 100 °C for copper. One-hour treatment in ODA + BTA vapors at these temperatures results in the formation of nanosized adsorption films on the surface of these metals. These films stabilize the passive state and provide efficient temporary protection of metal items. The ODA + BTA inhibitor is superior to its components in terms of protective aftereffect. Our analysis of the mutual effect of BTA and ODA indicated that they show an antagonism of protective action on copper, but there is also a synergistic enhancement in the case of brass. Electrochemical impedance spectroscopy studies demonstrate that the inhibitors in question mainly act by using a blocking mechanism on copper and brass. Chamber treatment of the metals studied in vapors of the ODA + BTA mixture resulted in a noticeable hydrophobization of the copper surface and an insignificant effect on the brass surface. Chamber treatment of copper samples with artificially created polymodal roughness made it possible to obtain a superhydrophobic surface. 相似文献
95.
Anastasiya S. Babkina Irina V. Ostrova Mikhail Ya Yadgarov Artem N. Kuzovlev Andrey V. Grechko Alexey V. Volkov Arkady M. Golubev 《Viruses》2022,14(2)
The increased plasma levels of von Willebrand factor (VWF) in patients with COVID-19 was reported in many studies, and its correlation with disease severity and mortality suggest its important role in the pathogenesis of thrombosis in COVID-19. We performed histological and immunohistochemical studies of the lungs of 29 patients who died from COVID-19. We found a significant increase in the intensity of immunohistochemical reaction for VWF in the pulmonary vascular endothelium when the disease duration was more than 10 days. In the patients who had thrombotic complications, the VWF immunostaining in the pulmonary vascular endothelium was significantly more intense than in nonsurvivors without thrombotic complications. Duration of disease and thrombotic complications were found to be independent predictors of increased VWF immunostaining in the endothelium of pulmonary vessels. We also revealed that bacterial pneumonia was associated with increased VWF staining intensity in pulmonary arterial, arteriolar, and venular endothelium, while lung ventilation was an independent predictor of increased VWF immunostaining in arterial endothelium. The results of the study demonstrated an important role of endothelial VWF in the pathogenesis of thrombus formation in COVID-19. 相似文献
96.
Parkhitko A Myachina F Morrison TA Hindi KM Auricchio N Karbowniczek M Wu JJ Finkel T Kwiatkowski DJ Yu JJ Henske EP 《Proceedings of the National Academy of Sciences of the United States of America》2011,108(30):12455-12460
Tuberous sclerosis complex (TSC) is a tumor suppressor syndrome characterized by benign tumors in multiple organs, including the brain and kidney. TSC-associated tumors exhibit hyperactivation of mammalian target of rapamycin complex 1 (mTORC1), a direct inhibitor of autophagy. Autophagy can either promote or inhibit tumorigenesis, depending on the cellular context. The role of autophagy in the pathogenesis and treatment of the multisystem manifestations of TSC is unknown. We found that the combination of mTORC1 and autophagy inhibition was more effective than either treatment alone in inhibiting the survival of tuberin (TSC2)-null cells, growth of TSC2-null xenograft tumors, and development of spontaneous renal tumors in Tsc2(+/-) mice. Down-regulation of Atg5 induced extensive central necrosis in TSC2-null xenograft tumors, and loss of one allele of Beclin1 almost completely blocked macroscopic renal tumor formation in Tsc2(+/-) mice. Surprisingly, given the finding that lowering autophagy blocks TSC tumorigenesis, genetic down-regulation of p62/sequestosome 1 (SQSTM1), the autophagy substrate that accumulates in TSC tumors as a consequence of low autophagy levels, strongly inhibited the growth of TSC2-null xenograft tumors. These data demonstrate that autophagy is a critical component of TSC tumorigenesis, suggest that mTORC1 inhibitors may have autophagy-dependent prosurvival effects in TSC, and reveal two distinct therapeutic targets for TSC: autophagy and the autophagy target p62/SQSTM1. 相似文献
97.
Jiri Dvorak Petr Kral Andrey G. Kadomtsev Vladimir I. Betekhtin Maria V. Narykova Marie Kvapilova Vaclav Sklenicka 《Materials》2022,15(5)
The commercial purity of VT1-0 titanium was processed by the rolling process and executed at elevated, room, and cryo-temperatures. These processings led to the formation of an ultrafine-grained microstructure, with the mean grain size at a nanometer level. Some of these materials were statically annealed at a temperature of 823 K for 1 h, which led to significant subgrains and grain coarsening. The constant load creep tests in tension were carried out in argon on all states of materials, at temperatures of 648–723 K and different ranges of applied stresses. From the value of the steady-state creep rate, the control creep mechanisms were determined. The microstructure analyses were carried out via SEM and TEM. It was found that titanium prepared at elevated and room temperatures have a higher creep strength than titanium prepared at cryo-temperatures. Furthermore, the post-SPD —annealing led to a significant decrease in the creep properties. The influence of the preparation temperature on the difference of the creep behavior were discussed and explained using the microstructure analyses of the tests’ samples. 相似文献
98.
Vladimir Shvartz Maria Sokolskaya Andrey Petrosyan Artak Ispiryan Sergey Donakanyan Leo Bockeria Olga Bockeria 《Pathophysiology》2022,29(1):106
Background: Understanding of the risk factors for the development of adverse outcomes after aortic valve replacement is necessary to develop timely preventive measures and to improve the results of surgical treatment. Methods: We analyzed patients with aortic stenosis (n = 742) who underwent surgical treatment in the period 2014–2020. The average age was 63 (57;69) years—men 58%, women 42%. Results: The hospital mortality rate was 3% (22 patients). The following statistically significant threshold values (cut-off points) were obtained in the ROC analysis: aortic cross-clamp time > 93 min AUC (CI) 0.676 (0.640–0.710), p = 0.010; cardiopulmonary bypass time > 144 min AUC (CI) 0.809 (0.778–0.837), p < 0.0001, hemoglobin before op <120 g/L. AUC (CI) 0.762 (0.728–0.793), p < 0.0001, hematocrit before op <39% AUC (CI) 0.755 (0.721–0.786), p < 0.001, end-diastolic dimension index >2.39 AUC (CI) 0.647 (0.607–0.686), p = 0.014, end-systolic dimension index > 1.68 AUC (CI) 0.657 (0.617–0.695), p = 0.009. Statistically significant independent predictors of hospital mortality were identified: BMI > 30 kg/m2 (OR 2.84; CI 1.15–7.01), ischemic heart disease (OR 3.65; CI 1.01–13.2), diabetes (OR 3.88; CI 1.38–10.9), frequent ventricular ectopy before operation (OR 9.78; CI 1.91–50.2), mitral valve repair (OR 4.47; CI 1.76–11.3), tricuspid valve repair (OR 3.06; CI 1.09–8.58), 3 and more procedures (OR 4.44; CI 1.67–11.8). Conclusions: The hospital mortality rate was 3%. The main indicators associated with the risk of death were: diabetes, overweight (body mass index more than 30 kg/m2), frequent ventricular ectopy before surgery, hemoglobin level below 120 g/L, hematocrit level below 39%, longer cardiopulmonary bypass time and aortic cross-clamp time, additional mitral and tricuspid valve interventions. 相似文献
99.
This review outlines current issues of the pharmacovigilance (PV) system in the Russian Federation, namely the present state of regulatory aspects, regulatory requirements in both Russia and the Eurasian Economic Union, and review of causes of under-reporting of adverse drug reactions. Specific attention will be focused on how the system is designed to monitor drug safety functions, reporting and accountability of pharmaceutical products, their manufacturers and medical staff, the role played by regional centers for drug-safety monitoring, and insufficient understanding of the part taken by patients in the system of PV. The prospects of the Russian PV system and its harmonization with global practice will also be discussed. 相似文献
100.