scholarly journals Scientific Review on the Ionospheric Absorption and Research Prospects of a Complex Eikonal Model for One-Layer Ionosphere

2014 ◽  
Vol 2014 ◽  
pp. 1-14 ◽  
Author(s):  
Alessandro Settimi ◽  
Alessandro Ippolito ◽  
Claudio Cesaroni ◽  
Carlo Scotto
Keyword(s):  
Simple Formula ◽  
Horizontal Gradient ◽  
Scientific Review ◽  
Eikonal Model ◽  
Ionospheric Absorption ◽  
Complex Eikonal

The present paper conducts a scientific review on ionospheric absorption, extrapolating the research prospects of a complex eikonal model for one-layer ionosphere. As regards the scientific review, here a quasi-longitudinal (QL) approximation for nondeviative absorption is deduced which is more refined than the corresponding equation reported by Davies (1990). As regards the research prospects, a complex eikonal model for one-layer ionosphere is analyzed in depth here, already discussed by Settimi et al. (2013). A simple formula is deduced for a simplified problem. A flat, layered ionospheric medium is considered, without any horizontal gradient. The authors prove that the QL nondeviative amplitude absorption according to the complex eikonal model is more accurate than Rawer’s theory (1976) in the range of middle critical frequencies.

MOLECULAR ASPECTS OF SARCOPENIA PATHOGENESIS IN CHRONOC KIDNEY DISEASE: INTEGRATED ROLE OF mTOR

2018 ◽  
Vol 22 (5) ◽  
pp. 9-16 ◽  
Author(s):  
M. Z. Gasanov
Keyword(s):  
Kidney Disease ◽  
Muscle Mass ◽  
Protein Metabolism ◽  
Mammalian Target Of Rapamycin ◽  
Healthy Person ◽  
Scientific Review ◽  
Cytoskeleton Organization ◽  
Molecular Aspects ◽  
End Stage

In recent decades, the main pathogenetic mechanisms for maintaining muscle mass and strength have been discovered. Most of the scientific papers on the molecular aspects of the  pathogenesis of sarcopenia were focused on the Akt-signaling  pathway. The subject of the study were people of elderly and senile  age, immobilized patients, patients with CKD 1-4 stages, animals. However, recently more attention has been paid to the role  of protein – the mammalian target of rapamycin mTOR. It seems to be a key link in the control of muscle mass and is a promising  marker in understanding the mechanisms of the pathogenesis of  sarcopenia. Its importance in protein metabolism in patients with  end stage kidney disease is not studied and requires further research. The presented scientific review contains  information on the role of mTOR and its components – mTORC1 and mTORC2 in maintaining muscle mass and strength in a healthy  person and in the formation of sarcopenia in patients with CKD. The  general aid of mTORC1 complex is regulation of protein production  which is necessary for cell growth and differentiation. mTORC2  complex functions are not enough studied. It is established that it  plays important role in such biological processes as cytoskeleton  organization, intracellular homeostasis maintaining, so it provides  cell resistance and cell survivability in negative external and internal  impulses. mTOR protein can be considered as promising molecular  marker in diagnostics of protein metabolism early disturbances in  patients with CKD and also as additory factor of sarcopenia severity assessment.

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