Endothelin-1 (ET-1) is a potent vasoconstrictor hormone that has been identified as an important factor
responsible for the development of cardiovascular dysfunctions. ET-1 exerts its vasoconstrictor activity
through two pharmacologically distinct receptors, ETA and ETB that are found in vascular smooth muscle
cells (VSMCs) and the vasodilator activity through an ETB receptor located on endothelial cells. This study
aimed to show the impact of 1µM L-arginine (LA), 100µM tetrahydrobiopterin (BH4), and their combined
effect on ET-1 activity in both lead-treated and lead-untreated rat aortic rings. This means, investigating how
endothelial dysfunction reverses the role of nitric oxide precursor and cofactor. In this study, Rat aortic rings
have been pre-incubated with BH4, LA and their combination. Subsequently, the aortic rings were preincubated with 200µM N-Nitro-L-arginine methyl ester (L-NAME) and 0.5µM BQ-123. Then, the vascular
response to cumulative doses of rat ET-1 was analyzed in each of the above-mentioned groups (LA, BH4, LA
& BH4, L-NAME, BQ-123), in the presence and absence of lead acetate 1µM Pb (C2H3O2)2. ET-1 efficacy and
potency were significantly decreased in the presence of LA, BH4, and LA and BH4 combination in the untreated
group, while it significantly increased in the presence of lead. In the second trial of experiments ET-1 efficacy
markedly decreased in BQ-123- incubated cells in both lead-treated and untreated aortic rings. In the presence
of lead, the efficacy of ET-1 was raised with the use of L-NAME. In conclusion, LA and BH4 can be considered
pharmacological agents to alter the potency of ET-1-induced vasoconstriction and concomitantly lower blood
pressure.
Metasurface polarizers are essential optical components in modern integrated optics and play a vital role in many optical applications including Quantum Key Distribution systems in quantum cryptography. However, inverse design of metasurface polarizers with high efficiency depends on the proper prediction of structural dimensions based on required optical response. Deep learning neural networks can efficiently help in the inverse design process, minimizing both time and simulation resources requirements, while better results can be achieved compared to traditional optimization methods. Hereby, utilizing the COMSOL Multiphysics Surrogate model and deep neural networks to design a metasurface grating structure with high extinction rat
... Show MoreThe use of blended cement in concrete provides economic, energy savings, and ecological benefits, and also provides. Improvement in the properties of materials incorporating blended cements. The major aim of this investigation is to develop blended cement technology using grinded local rocks . The research includes information on constituent materials, manufacturing processes and performance characteristics of blended cements made with replacement (10 and 20) % of grinded local rocks (limestone, quartzite and porcelinite) from cement.
The main conclusion of this study was that all ty
... Show MoreA simple and accurate method to determinate furosemide (FUR) based on converting the secondary amine to primary amine with acidic hydrolysis then azotization by nitrous acid and coupled with resorcinol as a coupling agent in aqueous medium at pH 13. The optical characteristic like beers law limit found to be (0.25-2.5) μg.ml−1, detection and quantification limits (0.0196) (0.0654) μg.ml−1respectivly and Sandel sensitivity was 0.006738 μg.cm−2. The least-square method was used to evaluate the regression equation and the correlation coefficient. The resulted azo dye has a maximum absorbance at 430 nm with light oran
Anaerobic digestion is a technology widely used for treatment of organic waste for biogas production as a source for clean energy. In this study, poultry house wastes (PHW) material was examined as a source for biogas production. The effects of inoculum addition, pretreatment of the substrate, and temperature on the biogas production were taken into full consideration. Results revealed that the effect of inoculum addition was more significant than the alkaline pretreatment of raw waste materials. The biogas recovery from inoculated waste materials exceeds its production from wastes without inoculation by approximately 70% at mesophilic conditions. Whereby, the increase of biogas recovery from pretreated wastes was by 20% higher than its
... Show MoreIn this work, some mechanical properties of the polymer coating were improved by preparing a hybrid system containing Graphene (GR) of different weight percentages (0.25, 0.5, 1, and 2wt%) with 5wt% carbon fibres (CF) and added to a polymer coating by using casting method. The properties were improved as GR was added with further improvement on adding 5wt% of CF. The impact strength of acrylic polymer with GR increases with increasing weight ratio of GR; maximum value was obtained when the polymer coating was incorporated with 1wt% GR and 5wt% CF. The impact strength of acrylic polymer with GR and GR/CF composites incorporated with GR at 1wt% and CF at 5wt%. Hardness increase with increasing weight ratio of Gr and a significant imp
... Show MoreMany condensed polymers [A1-A7] were prepared via reaction of (Ethylenediaminetetraacetic acid = EDTA), with different prepared imide-diamines by modification [ modification of amino acids and antibiotics (B1- B7)] Imide-diamines were prepared by chlorination of L-amino acids such as [ L-Histidine, L-Alanine, L-Valine, L-Glycine and L-Aspargine ] or selected antibiotics such as [Cephallixine monohydrate and Amoxilline ] with thionyl chloride at 0°C, then reacted with ammonia to obtain imidediamines [B1-B7] . The physical properties of all prepared condensed polymers [A1-A7], new prepared diamines [B1-B7] were studied and characterized by FT -IR spectroscope to certify the structural formulas. The thermal analysis (TGA, DTA) were studied, a
... Show MoreThis work includs synthesis of several Schiff bases by condensation of 6- methoxy – 2- amino benzothiazole with some aldehydes and ketones (2- hydroxyl benzaldehyde, 4- hydroxyl benzaldehyde, 4- N,N –dimethy amino acetophenone, benzophenone) to abtain schiff bases (1-5). These schiff bases were found to react with phthalate anhydride to give oxazepine derivatives (6-10) that were reacted with primary aromatic amines to give Diazepine derivatives (11-15). Besides, we prepared new tetrazole derivatives (16-20) from the reaction of the prepared Schiff bases with sodium azide in the prepared compounds that were characterized by physical properties, FT-IR and some of the 1H-NMR and 13C –NMR spectroscopy.
The objective of this research work is to evaluate the quality of central concrete plant of Al-Rasheed Company by using Six Sigma approach which is a measure of quality that strives for near elimination of defects using the statistical methods to improve outputs that are critical to customers. The fundamental objective of Six Sigma methodology is the implementation of a measurement-based strategy that focuses on process improvement and variation reduction to reach delighting customers, and then suggesting an improvement system to improve the production of concrete in Al-Rasheed State Contracting Construction Company.
A field survey includes two parts (open and close questionnaire) that aimed to get the data and information required f