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  • Closed Access
    Authors: 
    Ashot Avagimyan; Albina Kajaia; Luiza Gabunia; Ketevan Ghambashidze; Nodar Sulashvili; Levan Ratiani; Kiyan Heshmat-Ghahdarijani; Mohammad Sheibani; Artashes Aznauryan;
    Publisher: Elsevier BV

    Abstract Arterial hypertension is a highly urgent problem of modern medicine since the crisis of blood pressure control remains open, despite the increasing number of uncontrolled arterial hypertension. Today, one of the most critical problems of cardiology is the study of the mechanisms of development and progression of arterial hypertension. Therefore, our international and multidisciplinary working group presents a vision of a new therapeutic target - urotensin II in the pathogenesis of arterial hypertension. Thus, this article reflects the concept of the Armenian, Georgian and Iranian medical schools.

  • Closed Access
    Authors: 
    Ashot Avagimyan; Lilit Sukiasyan; Lev Kakturskiy; Lusine Mkrtchyan; Vergine Chavushyan; K Chelidze; Alexey Ionov; Ivan Pavluchenko;
    Publisher: Elsevier BV

    Today, cardiovascular diseases, due to their widespread prevalence, are among the most relevant biomedical problems in the modern world. The development of cardiovascular comorbidity among patients with diabetes mellitus is of high clinical urgency. Therefore, the study of cardiovascular risk modification among patients with diabetes mellitus is of paramount importance. In the context of the above, the data on the cardiotoxicity of fructose look very alarming since these patients usually use fructose as an affordable alternative to glucose. At the same time, it is an independent inducer of destabilization of cardiovascular homeostasis. Sixty rats were used in the experiment to study this problem. Modeling of fructose-induced overload was performed using a diabetic fructose supplement in an aqueous solution. The collection of herbs "Diabefit" was used as an infusion in addition to feeding highly enriched with fructose. The used markers which reflect the state of the heart and the blood vessels were: MDA, SOD, NO, and ET-1. MDA, ET-1, and NO concentrations demonstrated a significant increase in the fructose overload group and a significant decrease in the Diabefit group. At the same time, changes in SOD level as an indicator of the antioxidant reserve, on the contrary, implied a decrease in the group with a high fructose content and increased in the Diabefit group. All detected changes were associated with fructose-induced inhibition of SOD activity and its restoration using the Diabefit phyto-collection.

  • Publication . Article . Part of book or chapter of book . Other literature type . 2022

    This article examines the territorialization of party support in the Republic of Georgia as political parties in Georgia try to territorialize by aligning themselves to existing societal cleavages....

  • Closed Access
    Authors: 
    Rana Muhammad Adnan; Zaher Mundher Yaseen; Salim Heddam; Shamsuddin Shahid; Aboalghasem Sadeghi-Niaraki; Ozgur Kisi;
    Publisher: Elsevier BV

    Abstract Reliable modeling of river sediments transport is important as it is a defining factor of the economic viability of dams, the durability of hydroelectric-equipment, river susceptibility to pollution, suitability for navigation, and potential for aesthetics and fish habitat. The capability of a new machine learning model, fuzzy c-means based neuro-fuzzy system calibrated using the hybrid particle swarm optimization-gravitational search algorithm (ANFIS-FCM-PSOGSA) in improving the estimation accuracy of river suspended sediment loads (SSLs) is investigated in the current study. The outcomes of the proposed method were compared with those obtained using the fuzzy c-means based neuro-fuzzy system calibrated using particle swarm optimization (ANFIS-FCM-PSO), ANFIS-FCM, and sediment rating curve (SRC) models. Various input combinations involving lagged river flow (Q) and suspended sediment (S) values were used for model development. The effect of Q and S on the model's accuracy also was assessed by including the difference between lagged Q and S values as inputs. The model performance was assessed using the root mean square error (RMSE), mean absolute error (MAE), Nash-Sutcliffe Efficiency (NSE), and coefficient of determination (R2) and several graphical comparison methods. The results showed that the proposed model enhanced the prediction performance of the ANFIS-FCM-PSO (or ANFIS-FCM) models by 8.14% (1.72%), 14.7% (5.71%), 12.5% (2.27%), and 25.6% (1.86%), in terms of the RMSE, MAE, NSE and R2, respectively. The current study established the potential of the proposed ANFIS-FCM-PSOGSA model for simulation of the cumulative sediment load. The modeling results revealed the potential effects of the river flow lags on the sediment transport quantification.

  • Authors: 
    Elham Al Fares; Tamar Sanikidze; Sophio Kalmakhelidze; David Topuria; Luigi Mansi; Sean L. Kitson; Mikaeil Molazadeh;
    Publisher: Bentham Science Publishers Ltd.

    Background and Objective: Herniarin is a simple coumarin that is found naturally in some plant species. In this study, we aimed to evaluate the protective effect of herniarin against ionizing radiation-induced genotoxicity and cytotoxicity in human peripheral blood lymphocytes. Methods: Herniarin was added to human lymphocytes before irradiation with a dose of 2 Gy of Xrays. The antagonistic potential of herniarin against radiation was measured by MTT [3-(4,5- dimethyl-2-thiazolyl)-2,5-diphenyl-2H tetrazolium bromide] assay, micronucleus assay, flow cytometry, and reactive oxygen species (ROS) level analysis. Results: The maximum survival of lymphocytes against radiation was observed at a concentration of 50 μM of herniarin and a treatment time of 1 h. Pretreatment with 50 μM herniarin significantly decreased the micronuclei frequency, the percentage of apoptotic lymphocytes, and the ROS level in irradiated human lymphocytes. Moreover, 50 μM herniarin significantly increased the cytokinesis blocked proliferation index in irradiated lymphocytes. Conclusion: Herniarin could reduce radiation-induced cytotoxicity and genotoxicity in human lymphocytes. To complete the results of this study, it is suggested that in the future, more preclinical studies with larger samples or animal models be performed on herniarin.

  • Publication . Other literature type . Article . Preprint . 2022
    Open Access English
    Authors: 
    Jennifer Schober; Igor Rogachevskii; Axel Brandenburg;
    Country: Switzerland
    Project: SNSF | Magnetohydrodynamical dyn... (185863)

    In relativistic magnetized plasmas, asymmetry in the number densities of left- and right-handed fermions, i.e., a non-zero chiral chemical potential mu_5, leads to an electric current along the magnetic field. This causes a chiral dynamo instability for a uniform mu_5, but our simulations reveal a dynamo even for fluctuating mu_5 with zero mean. It produces magnetically-dominated turbulence and generates mean magnetic fields via the magnetic alpha effect. Eventually, a universal scale-invariant k^(-1) spectrum of mu_5 and a k^(-3) magnetic spectrum are formed independently of the initial condition. 6 pages, 4 figures, published in Phys. Rev. Lett

  • Publication . Other literature type . Article . Preprint . 2022
    Open Access English
    Authors: 
    Jennifer Schober; Igor Rogachevskii; Axel Brandenburg;
    Country: Switzerland
    Project: SNSF | Magnetohydrodynamical dyn... (185863)

    We study the dynamics of magnetic fields in chiral magnetohydrodynamics, which takes into account the effects of an additional electric current related to the chiral magnetic effect in high energy plasmas. We perform direct numerical simulations, considering weak seed magnetic fields and inhomogeneities of the chiral chemical potential mu_5 with a zero mean. We demonstrate that a small-scale chiral dynamo can occur in such plasmas if fluctuations of mu_5 are correlated on length scales that are much larger than the scale on which the dynamo growth rate reaches its maximum. Magnetic fluctuations grow by many orders of magnitude due to the small-scale chiral dynamo instability. Once the nonlinear backreaction of the generated magnetic field on fluctuations of mu_5 sets in, the ratio of these scales decreases and the dynamo saturates. When magnetic fluctuations grow sufficiently to drive turbulence via the Lorentz force before reaching maximum field strength, an additional mean-field dynamo phase is identified. The mean magnetic field grows on a scale that is larger than the integral scale of turbulence after the amplification of the fluctuating component saturates. The growth rate of the mean magnetic field is caused by a magnetic alpha effect that is proportional to the current helicity. With the onset of turbulence, the power spectrum of mu_5 develops a universal k^(-1) scaling independently of its initial shape, while the magnetic energy spectrum approaches a k^(-3) scaling. 22 pages, 22 figures

  • Publication . Article . Preprint . 2022
    Open Access English
    Authors: 
    Yonghui Lin; Hans-Werner Hammer; Ulf-G. Meißner;
    Publisher: APS
    Project: EC | STRONG-2020 (824093)

    We present a combined analysis of the electromagnetic form factors of the nucleon in the space- and timelike regions using dispersion theory. Our framework provides a consistent description of the experimental data over the full range of momentum transfer, in line with the strictures from analyticity and unitarity. The statistical uncertainties of the extracted form factors are estimated using the bootstrap method, while systematic errors are determined from variations of the spectral functions. We also perform a high-precision extraction of the nucleon radii and find good agreement with previous analyses of spacelike data alone. For the proton charge radius, we find $r_E^p = 0.840^{+0.003}_{-0.002}{}^{+0.002}_{-0.002}$~fm, where the first error is statistical and the second one is systematic. The Zemach radius and third moment are in agreement with Lamb shift measurements and hyperfine splittings. The combined data set of space- and timelike data disfavors a zero crossing of $\mu_p G_E^p/G_M^p$ in the spacelike region. Finally, we discuss the status and perspectives of modulus and phase of the form factors in the timelike region in the context of future experiments as well as the onset of perturbative QCD. Comment: 7 pages, 4 figures

  • Authors: 
    Natia Sordia; Emanuel Jauk; Khatuna Martskvishvili;
    Publisher: American Psychological Association (APA)
  • Open Access
    Authors: 
    Duglas Ugulava; David Zarnadze;
    Publisher: Elsevier BV

    Abstract The equation A u = f with a linear symmetric positive definite operator A : D ( A ) ⊂ H → H having a discrete spectrum and dense image in a complex Hilbert space H is considered. This equation is transferred into the Hilbert space of finite orbits D ( A n ) as well as into the Frechet space of all orbits D ( A ∞ ) , that is, the projective limit of the sequence of spaces { D ( A n ) } . For an approximate solution of the inverse of A, linear spline central algorithms in these spaces are constructed. The convergence of the sequence of approximate solutions to the exact solution is proved. The obtained results are applied to the quantum harmonic oscillator operator A u ( t ) = − u ″ ( t ) + t 2 u ( t ) , t ∈ R , in the Hilbert space of finite orbits D ( A n ) , and in the Frechet space of all orbits D ( A ∞ ) that in this case coincides with the Schwartz space of rapidly decreasing functions. Some quantum mechanical interpretations of obtained results are also given.

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