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1.
Margarita A. Sazonova Vasily V. Sinyov Anastasia I. Ryzhkova Marina D. Sazonova Tatiana V. Kirichenko Victoria A. Khotina Zukhra B. Khasanova Natalya A. Doroschuk Vasily P. Karagodin Alexander N. Orekhov Igor A. Sobenin 《International journal of molecular sciences》2021,22(2)
Chronic stress is a combination of nonspecific adaptive reactions of the body to the influence of various adverse stress factors which disrupt its homeostasis, and it is also a corresponding state of the organism’s nervous system (or the body in general). We hypothesized that chronic stress may be one of the causes occurence of several molecular and cellular types of stress. We analyzed literary sources and considered most of these types of stress in our review article. We examined genes and mutations of nuclear and mitochondrial genomes and also molecular variants which lead to various types of stress. The end result of chronic stress can be metabolic disturbance in humans and animals, leading to accumulation of reactive oxygen species (ROS), oxidative stress, energy deficiency in cells (due to a decrease in ATP synthesis) and mitochondrial dysfunction. These changes can last for the lifetime and lead to severe pathologies, including neurodegenerative diseases and atherosclerosis. The analysis of literature allowed us to conclude that under the influence of chronic stress, metabolism in the human body can be disrupted, mutations of the mitochondrial and nuclear genome and dysfunction of cells and their compartments can occur. As a result of these processes, oxidative, genotoxic, and cellular stress can occur. Therefore, chronic stress can be one of the causes forthe occurrence and development of neurodegenerative diseases and atherosclerosis. In particular, chronic stress can play a large role in the occurrence and development of oxidative, genotoxic, and cellular types of stress. 相似文献
2.
Loboda P. I. Minitsky A. V. Byba Ye. G. Sysoev M. O. Radchuk S. V. 《Powder Metallurgy and Metal Ceramics》2020,58(11-12):651-656
Powder Metallurgy and Metal Ceramics - The infiltration of aluminum melts into porous metal skeletons produced by powder metallurgy methods, including 3D printing, under a pressure gradient was... 相似文献
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Kazuo Tsubota Stephen C. Pflugfelder Zuguo Liu Christophe Baudouin Hyo Myung Kim Elisabeth M. Messmer Friedrich Kruse Lingyi Liang Jimena Tatiana Carreno-Galeano Maurizio Rolando Norihiko Yokoi Shigeru Kinoshita Reza Dana 《International journal of molecular sciences》2020,21(23)
Over the past decades, the number of patients with dry eye disease (DED) has increased dramatically. The incidence of DED is higher in Asia than in Europe and North America, suggesting the involvement of cultural or racial factors in DED etiology. Although many definitions of DED have been used, discrepancies exist between the various definitions of dry eye disease (DED) used across the globe. This article presents a clinical consensus on the definition of DED, as formulated in four meetings with global DED experts. The proposed new definition is as follows: “Dry eye is a multifactorial disease characterized by a persistently unstable and/or deficient tear film (TF) causing discomfort and/or visual impairment, accompanied by variable degrees of ocular surface epitheliopathy, inflammation and neurosensory abnormalities.” The key criteria for the diagnosis of DED are unstable TF, inflammation, ocular discomfort and visual impairment. This definition also recommends the assessment of ocular surface epitheliopathy and neurosensory abnormalities in each patient with suspected DED. It is easily applicable in clinical practice and should help practitioners diagnose DED consistently. This consensus definition of DED should also help to guide research and clinical trials that, to date, have been hampered by the lack of an established surrogate endpoint. 相似文献
5.
Zavadiuk S.V. Loboda P.I. Soloviova T.O. Trosnikova I.Iu. Karasevska O.P. 《Powder Metallurgy and Metal Ceramics》2020,59(1-2):22-28
Powder Metallurgy and Metal Ceramics - The properties of sintered and heat-treated steels produced from the Catamold 8740 material by powder injection molding were examined. Parts made of the... 相似文献
6.
The paper concerns an analysis of an equilibrium problem for 2D elastic body with two semirigid inclusions. It is assumed that inclusions have a joint point, and we investigate a junction problem for these inclusions. The existence of solutions is proved, and different equivalent formulations of the problem are proposed. We investigate a convergence to infinity of a rigidity parameter of the semirigid inclusion. It is proved that in the limit, we obtain an equilibrium problem for the elastic body with a rigid inclusion and a semirigid one. A parameter identification problem is investigated. In particular, the existence of a solution to a suitable optimal control problem is proved. 相似文献
7.
An artistic rendering method of free-form surfaces with the aid of half-toned text that is laid-out on the given surface is presented. The layout of the text is computed using symbolic composition of the free-form parametric surface S(u, v) with cubic or linear Bézier curve segments C(t) = {cu (t), cv (t)} , comprising the outline of the text symbols. Once the layout is constructed on the surface, a shading process is applied to the text, affecting the width of the symbols as well as their color, according to some shader function. The shader function depends on the surface orientation and the view direction as well as the color and the direction or position of the light source. 相似文献
8.
This paper presents work directed at capturing the entrepreneurial and collaborative activity of university researchers. The Triple Helix points to the emergence of the entrepreneurial university as well as to an increasing overlay of activities in universities, industry and government. This study explores ways in which patent-based metrics could be utilized in a Triple Helix context, and how hybrid indicators could be developed by combining patent with survey data. More specifically, it aims to develop indicators that connect technological inventiveness of university researchers to both funding organizations and users, as well as to entrepreneurial activities by academics. The paper develops a simplified model of the innovation process to benchmark the relevance of the indicators to the Triple Helix. An analysis of Finnish academic patents illustrates that patent data can already provide useful indicators but, on its own, cannot provide information about how academic patents are interconnected with government or industry through funding or utilization links. An exclusive analysis of patents can point to patent concentrations on certain universities, to inventors and assignees, or to potential gaps in translating applied science into industrial technology. However, the patent data had to be combined with an inventor survey in order to relate academic patents more to their Triple Helix environment. The survey indicated that most patented academic inventions are connected to (often publicly funded) scientific research by the inventors and tend to be utilized in large firms rather than in start-up companies founded by academic entrepreneurs. 相似文献
9.
Montress G.K. Parker T.E. Loboda M.J. 《IEEE transactions on ultrasonics, ferroelectrics, and frequency control》1994,41(5):664-679
The results of residual phase noise measurements on a number of VHF, UHF, and microwave amplifiers, both silicon (Si) bipolar junction transistor (BJT) and gallium arsenide (GaAs) field effect transistor (FET) based, electronic phase shifters, frequency dividers and multipliers, etc., which are commonly used in a wide variety of frequency source and synthesizer applications are presented. The measurement technique has also been used to evaluate feedback oscillator components, such as the loop and buffer amplifiers, which can play important roles in determining an oscillator's output phase noise spectrum (often in very subtle ways). While some information has previously been published related to component residual phase noise properties, it generally focused on the flicker noise levels of the devices under test, for carrier offset frequencies less than 10 kHz. The work reported herein makes use of an extremely low noise, 500 MHz surface acoustic wave resonator oscillator (SAWRO) test source for residual phase noise measurements, both close-to-and far-from-the-carrier. Using this SAWRO-based test source at 500 MHz, we have been able to achieve a measurement system phase noise floor of -184 dBc/Hz, or better, for carrier offset frequencies greater than 10 kHz, and a system flicker phase noise floor of -150 dBc/Hz, or better, at 1 Hz carrier offset. The paper discusses the results of detailed residual phase noise measurements performed on a number of components using this overall system configuration. Several interesting observations related to the residual phase noise properties of moderate to high power RF amplifiers, i.e., amplifiers with 1 dB gain compression points in the range of +20 to +33 dBm, are highlighted 相似文献
10.