Background: Mitral valve stenosis is a condition in which the hearts mitral valve is narrowed (stenosis), This narrowing blocks the valve from opening properly obstructing blood flow through the heart and the rest of the body and this causes changes in physical parameters (resistance and conductance). Aim of the study: To assess the changes in the physical parameters in mitral valve stenosis disease in different gender and age by using Doppler ultrasound. Methods : The examination of patients at the Division of Echo - at the Iraqi Center for Heart Disease in Medical City for surgery specialist - Baghdad - Iraq, during(February2009 till November2010). The current study included fifty eight cases containing (27 males and 31 females) ages ranging between (16- 82) and is divided between 29 people from healthy people (I) which contain (13 males and 16 females) ages ranging between (16- 82) and a standard deviation of 22.6. Twenty nine of patients with mitral valve stenosis were divided into group (II) contains (6 males and 8 females) ages ranging between (28-76) and the standard deviation of 17.8, group (III) contains (5 males and 4 females) ages ranging between (40-71) and the standard deviation of 16.1 and group (IV) contain (3 male and 3 female) ages ranging between (56-72) and the standard deviation of 17.9. Studying changes developments in physical factors resulting from mitral valve stenosis and depending on these factors were calculated to change the resistance and conductivity and studying the relationship of the change in area and the change of physical factors. Results: The flow rate and area of mitral valve was significantly less in group IV than other groups, but pressure gradient, max velocity, pressure half time, max pressure were higher and more significantly in group IV. Resistance is significantly increases and it is higher in group IV compared with other groups. Conductance is higher in group I but more significant in group II. Conclusion: There is a strong correlation between the pressure half time and area of mitral valve. Resistance was significantly increased and it is higher in sever mitral stenosis. Conductance is high in mild mitral stenosis. The increase in mitral pressure gradient is frequently compensated by a decreased conductance. Age was highly influential but sex exerts less influence to change the physical parameters.
In this study, condensation polymerization was used to synthesize a number of novel liquid crystal polymers with 1,3,4-oxadiazole rings based on melamine. The new synthesized polymers were characterized by Fourier transform infrared (FTIR) and proton nuclear magnetic resonance (1HNMR) spectroscopy. Differential scanning calorimetry (DSC) and optical polarization microscopy (OPM) were used to investigate their liquid crystalline properties. The results demonstrated that throughout a wide temperature range, most of the polymers exhibited columnar (CohX) and nematic (N) liquid crystalline phases.
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Linear motor offers several features in many applications that require linear motion. Nevertheless, the presence of cogging force can deteriorate the thrust of a permanent magnet linear motor. Using several methodologies, a design of synchronous single sided linear iron-core motor was proposed. According to exact formulas with surface-mounted magnets and concentrated winding specification, which are relying on geometrical parameters. Two-dimensional performance analysis of the designed model and its multi-objective optimization were accomplished as a method to reduce the motor cogging force using MAXWELL ANSYS. The optimum model design results showed that the maximum force ripple was approximatrly reduced by 81.24%compared to the origina
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Objective: Synthesis, Characterization of formazan derivatives and studies the antioxidant activity of prepared compounds and molecular docking. Methods: In this study, formazan compounds (III–XIV) were produced by combining Schiff base compounds (I), (II) with diazonium salts resulting from reactions of different aromatic amines with sodium nitrate in the presence of Con.HCl at 0–5°C. When isonicotinic acid hydrazide reacts with (N,N-dimethylbenzaldehyde, 4-hydroxy-3-methoxybenzaldehyde) in the presence glacial acetic acid as a solvent Schiff base compounds are created. Results: The prepared compounds were identified by FT-IR, 1H NMR, 13C NMR, then the antioxidant activity of the derivatives and molecular docking were studied. D
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IA Ali, FK Emran, DF Salloom, Annals of the Romanian Society for Cell Biology, 2021
Periodontitis is one of the most prevalent bacterial diseases affecting man with up to 90% of the global population affected. Its severe form can lead to the tooth loss in 10-15% of the population worldwide. The disease is caused by a dysbiosis of the local microbiota and one organism that contributes to this alteration in the bacterial population is Prophyromonas gingivalis. This organism possesses a range of virulence factors that appear to contribute to its growth and survival at a periodontal site amongst which is its ability to invade oral epithelial cells. Such an invasion strategy provides a means of evasion of host defence mechanisms, persistence at a site and the opportunity for dissemination to other sites in the mouth. However, p
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