Objectives: To assess the changes in blood vessel stiffness and digital pulse wave amplitude because of flowmediateddilatation, and to explore how these two variables change when endothelial dysfunction isexperimentally induced.Method: The experimental study was conducted at the departments of physiology at the College of Medicine,Mustansiriyah University, and the College of Medicine, Al-Iraqia University, Baghdad, Iraq, from October 14, 2021, toMay 31, 2022, and comprised healthy young males who were subjected to the flow-mediated dilatation techniqueon the left brachial artery. Pulse transit time and the amplitude of the digital pulse wave were measured duringreactive hyperaemia for 2.5 minutes from the left middle finger using a piezoelectric pressure sensor and asimultaneous Lead I electrocardiogram. Endothelial dysfunction (ED) was induced by oscillatory and retrogradeshear rates. The correlation between variables was calculated in Excel running on the Windows operating system.Results: There were 10 second-year medical students with mean age 22±0 years and mean body mass index25.7±4.8kg/m2. During reactive hyperaemia, pulse transit time was significantly increased by 3-5% in both normalendothelium and experimentally induced endothelial dysfunction relative to the pre-occluded artery, and thedifference was not significant (p>0.05). Digital pulse wave amplitude increased significantly in normal endotheliumrelative to the pre-occluded artery (p<0.05), but not in experimentally-induced endothelial dysfunction (p>0.05).Conclusion: The pulse transit time and digital pulse wave amplitudes of the photo plethysmography signal may beused to detect changes in vessel wall diameter and tone throughout the reactive hyperaemia process. Digital pulsewave amplitude was better able to detect experimentally-induced endothelial dysfunction, as assessed by the flowmediateddilatation protocol, than pulse transit time.Key Words: Hyperemia, Brachial Artery, Dilatation, Plethysmography, Electrocardiography, Pulse Wave,Endothelium, Running
Diabetes mellitus can be defined as a metabolic disorder disease .Complication of diabetes are due to diabetic nephropathy .This study was done in vitro to study the effect of different concentrations of erlotinib inhibitor ( tyrosine kinase inhibitor) on electrolyte levels (MgâºÂ²,CaâºÂ²,Naâº) in sera of Iraqi patients with newly diagnosis type2 diabetes and diabetic nephropathy in addition to find the best percentage inhibition for utilizing different concentrations from erlotinib (6.97x10â»â·, 9.30x10â»â· ,1.16x10â»â¶,1.39x10â»â¶ ,1.62x10â»âµ )molar on electrolyte levels . This study was conducted in The National Diabetes Ce
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The approach maintenance and replacement one of techniques of operations research whom cares of the failure experienced by a lot of production lines which consist of a set of machines and equipment, which in turn exposed to the failure or work stoppages over the lifetime, which requires reducing the working time of these machines or equipment below what can or conuct maintenance process once in a while or a replacement for one part of the machine or replace one of the machines in production lines. In this research is the study of the failure s that occur in some parts of one of the machines for the General Company for Vege
... Show MoreThis paper presents a newly developed method with new algorithms to find the numerical solution of nth-order state-space equations (SSE) of linear continuous-time control system by using block method. The algorithms have been written in Matlab language. The state-space equation is the modern representation to the analysis of continuous-time system. It was treated numerically to the single-input-single-output (SISO) systems as well as multiple-input-multiple-output (MIMO) systems by using fourth-order-six-steps block method. We show that it is possible to find the output values of the state-space method using block method. Comparison between the numerical and exact results has been given for some numerical examples for solving different type
... Show MoreIn this study many specimen s were prepared from 2024-T3 Aluminum alloy for corrosion test by the dimensions of (15*15*3) mm according to ASTM G71-31 and then subjected to shot peening process at different time (15, 30, 45) minutes using steel ball having a diameter of 2.75 mm and Rockwell Hardness of 55RC to induce compressive residual stress which were measured using X-Ray diffraction method, surface roughness and hardness were tested before and after peening. Electrochemical corrosion test by Tafel extrapolation method was carried out in an environment of 3 .5% NaCl solutions (sea water) where Corrosion rate calculated using Tafle equation.
The obtained results show a favorable influence of SP treatment
... Show MoreArtificial Neural networks (ANN) are powerful and effective tools in time-series applications. The first aim of this paper is to diagnose better and more efficient ANN models (Back Propagation, Radial Basis Function Neural networks (RBF), and Recurrent neural networks) in solving the linear and nonlinear time-series behavior. The second aim is dealing with finding accurate estimators as the convergence sometimes is stack in the local minima. It is one of the problems that can bias the test of the robustness of the ANN in time series forecasting. To determine the best or the optimal ANN models, forecast Skill (SS) employed to measure the efficiency of the performance of ANN models. The mean square error and
... Show MoreAs they are the smallest functional parts of the muscle, motor units (MUs) are considered as the basic building blocks of the neuromuscular system. Monitoring MU recruitment, de-recruitment, and firing rate (by either invasive or surface techniques) leads to the understanding of motor control strategies and of their pathological alterations. EMG signal decomposition is the process of identification and classification of individual motor unit action potentials (MUAPs) in the interference pattern detected with either intramuscular or surface electrodes. Signal processing techniques were used in EMG signal decomposition to understand fundamental and physiological issues. Many techniques have been developed to decompose intramuscularly detec
... Show MoreIn this paper, the reliability and scheduling of maintenance of some medical devices were estimated by one variable, the time variable (failure times) on the assumption that the time variable for all devices has the same distribution as (Weibull distribution.
The method of estimating the distribution parameters for each device was the OLS method.
The main objective of this research is to determine the optimal time for preventive maintenance of medical devices. Two methods were adopted to estimate the optimal time of preventive maintenance. The first method depends on the maintenance schedule by relying on information on the cost of maintenance and the cost of stopping work and acc
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