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Author(s): S M Mercanlıgil [1]; P Arslan [1]; C Alasalvar [2]; E Okut [1]; E Akgül [3]; A Pınar [4]; P à Geyik [5]; L Tokgözoğlu [3]; F Shahidi [6] [...]

In this article, we investigate the mechanics of breathing performed by a ventilator with different kernels by an effective integral transform. We mainly obtain the solutions of the fractional respiratory mechanics model. Our goal is to give the underlying model flexibly by making use of the advantages of the non-integer order operators. The big advantage of fractional derivatives is that we can formulate models describing much better the systems with memory effects. Fractional operators with different memories are related to different types of relaxation process of the non-local dynamical systems. Additionally, since we consider the utilisation of different kinds of fractional derivatives, most often having benefit in the implementation, the similarities and differences can be obviously seen between these derivatives.

In this research, we analyze the magnetohydrodynamics heat act of a viscous incompressible Jeffrey nanoliquid, which passed in the neighborhood of a linearly extending foil. As a process, we employ alumina (Al2O3)\left({{\rm{Al}}}_{2}{{\rm{O}}}_{3}) as nanoparticles, assuming that the base fluid is ethylene glycol. In this involvement, we consider the heating by Joule effect and viscous dissipation. We select the passable transformations, motion, and temperature formulas converting into non-linear differential equation arrangement. We solved the system by using a Keller-box method. Then, we provide a graphical description of outcomes according to the selected control parameters. Higher values of dissipation parameter cause a surge in temperature field as well as strengthen width of the heat boundary layer. The velocity, drag coefficient, and heat transfer (HT) rate for the base fluid are comparatively greater than that of the Al2O3{{\rm{Al}}}_{2}{{\rm{O}}}_{3}–ethylene glycol nanofluid, although the temperature is embellished by the inclusion of nanoparticles. Moreover, we report depreciation in surface drag as well as HT by the virtue of amplification in the Deborah number. The proclaimed outcomes are advantageous to boost the incandescent light bulb’s, cooling and heating processes, filament emitting light, energy generation, multiple heating devices, etc.

Background: Hormone replacement therapy (HRT) is associated with reduced cardiovascular risk, but the underlying mechanism(s) are not fully understood. This study investigated the effects of a 6-month course of HRT on cardiac autonomic function parameters assessed by heart rate variability (HRV) in postmenopausal women.Methods: Forty-six healthy postmenopausal women (age 48 +/- 5, range 40-60) with normal baseline electrocardiogram and negative exercise testing were enrolled. HRT, which was either 0.625 mg/day conjugated equine estrogen (CEE) plus 2.5 mg/day medroxyprogesterone acetate or 0.625 mg/day CEE alone were administered depending on hysterectomy status. Power spectral analysis of HRV was performed to calculate the low frequency component in absolute (LF) and normalized units (LF nu), high frequency component in absolute (HF), and normalized units (HF nu), and the LF/HF ratio. The standard deviation of RR intervals (SDNN) was calculated from the time series of RR intervals.Results: A 6-month course of HRT did not significantly alter resting heart rate (P > 0.05). The LF/HF ratio and LF nu significantly decreased after HRT (P = 0.022 and P = 0.032), whereas a significant increase was noted in the HF component of HRV (P = 0.043), indicating an improvement in cardiac autonomic function. The SDNN value, which was 28.8 +/- 11.8 ms before HRT significantly increased to 35.4 +/- 16.7 ms after 6 months (P = 0.011).Conclusion: Our results indicate that a 6-month course of HRT may significantly improve cardiac autonomic function parameters, a finding that could at least partly explain the potential cardioprotective effect(s) of HRT. [ABSTRACT FROM AUTHOR]

Background: The aim of the study was to investigate the effects of hormone replacement therapy (HRT) on myocardial repolarization characteristics in postmenopausal women without coronary artery disease.Methods: Fifty-one consecutive healthy postmenopausal women (age 48 +/- 5) with negative exercise stress testing were prospectively enrolled into the study. Standard 12-lead electrocardiograms were obtained to evaluate the effects of 6 months of HRT on QT intervals, corrected QT intervals (QTcmax and QTcmin), QT dispersion (QTd), and corrected QTd (QTcd). Hormone regimens were continuous 0.625 mg/day conjugated equine estrogen (CEE) plus 2.5 mg/day medroxyprogesterone acetate (MPA) or 0.625 mg/day CEE alone depending on the hysterectomy status.Results: Although not statistically significant, CEE alone or in combination with MPA increased QTmax and QTmin values. However, the increase in QTmin was greater than the increase in QTmax, which resulted in statistically significant shortening of QTd (P = 0.007 in CEE and P < 0.001 in CEE + MPA groups). There was a significant prolongation of QTcmin values after 6 months in patients assigned to the CEE group (P = 0.001). The QTcd values were significantly shortened by HRT with both regimens (for CEE group 49 +/- 13 ms vs 38 +/- 13 ms, P = 0.01; for CEE + MPA group 49 +/- 14 ms vs 36 +/- 13, P < 0.001).Conclusion: HRT significantly decreased the QTd and QTcd in postmenopausal women without coronary artery disease, independent of the addition of MPA to the regimen. This improvement in myocardial repolarization may be one of the mechanisms of the favorable effects of HRT on cardiovascular system. However, the clinical implications of the shortening of QTd in postmenopausal women with HRT must be clarified. [ABSTRACT FROM AUTHOR]

The aim of this work is to tackle the three–dimensional (3D) Heston– Cox–Ingersoll–Ross (HCIR) time–dependent partial differential equation (PDE) computationally by employing a non–uniform discretization and gathering the finite difference (FD) weighting coe cients into differentiation matrices. In fact, a non–uniform discretization of the 3D computational domain is employed to achieve the second–order of accuracy for all the spatial variables. It is contributed that under what conditions the proposed procedure is stable. This stability bound is novel in literature for solving this model. Several financial experiments are worked out along with computation of the hedging quantities Delta and Gamma.

Introduction: Oxidative stress and inflammation are the basic molecular mechanisms in bilirubin neurotoxicity. We aimed to investigate the relationship between serum bilirubin and an antioxidant, anti-inflammatory and neuroprotective peptid, adrenomedullin (AM) levels. Methods: The correlation between serum bilirubin and AM levels was investigated in a total of 87 newborns. Newborns were further divided into two groups according to the serum bilirubin levels. Group I (with significant hyperbilirubinemia) and Group II (without significant hyperbilirubinemia) were compared with respect to demographic, anthropometric and biochemical parameters including serum AM levels. Results: In the correlation analysis, a significant positive correlation was detected between serum indirect bilirubin and AM levels in 87 newborns ( p < 0.001, r = 0.945). In demographic, anthropometric and biochemical comparison of the two study groups, serum indirect bilirubin levels were 21.53 ± 3.59 and 9.37 ± 4.87 mg/dl in Groups I and II, respectively ( p < 0.001), and serum AM levels were 1.45 ± 0.06 and 1.28 ± 0.07 ng/ml in Groups I and II, respectively ( p < 0.001) Conclusion: AM probably plays a significant role in adverse effects and neuronal injury steps of significant hyperbilirubinemia. In parallel with the results of this study the role, effects and physiopathological basis of AM in neonatal hyperbilirubinemia should be established especially with further animal studies. Results of this study may be used in establishing reference values for AM as there are very limited number of studies in newborns. [ABSTRACT FROM AUTHOR]

Examines the use of the helical computed tomography on variations of portal venous branching. Prevalence of intraheptic portal venous variations; Feasibility of tumor resection and planning the operative approach; Classification of the arterioportographic study.

Reproducing kernel functions are obtained for the solution of generalized Kuramoto–Sivashinsky (GKS) equation in this paper. These reproducing kernel functions are valuable in the reproducing kernel Hilbert space method. They will be useful for interested researchers.

Higher order differential equations have always been an onerous problem to investigate for the mathematicians and engineers. Different numerical methods were applied to get numerical approximations of such problems. This paper gives some reproducing kernel functions to find approximate solutions of the tenth-order boundary value problems (BVPs). These reproducing kernel functions are very important in the reproducing kernel Hilbert space method.