Double-layer micro-perforated panels (MPPs) have been studied extensively as sound absorption systems to increase the absorption performance of single-layer MPPs. However, existing proposed models indicate that there is still room for improvement regarding the frequency bands of absorption for the double-layer MPP. This study presents a double-layer MPP formed with two single MPPs with inhomogeneous perforation backed by multiple cavities of varying depths. The theoretical formulation is developed using the electrical equivalent circuit method to calculate the absorption coefficient under a normal incident sound. The simulation results show that the proposed model can produce absorption coefficient with wider absorption bandwidth compared with the conventional double- and even triple-layer MPPs. The bandwidth can be increased to higher frequency by decreasing the cavity depth behind a sub-MPP with small hole diameter and a high perforation ratio, and to lower frequency by increasing the cavity depth behind a sub-MPP with large hole diameter and a small perforation ratio. The experimental data, measured by impedance tube, are in good agreement with the predicted results.
A potential alternative energy resource to meet energy demands is the vast amount of gas stored in hydrate reserves. However, major challenges in terms of exploration and production surround profitable and effective exploitation of these reserves. The measurement of acoustic velocity is a useful method for exploration of gas hydrate reserves and can be an efficient method to characterize the hydrate-bearing sediments. In this study, the compressional wave velocity (P-wave velocity) of consolidated sediments (Bentheimer) with and without tetrahydrofuran hydrate-bearing pore fillings were measured using the pulse transmission method. The study has found that the P-wave velocity of consolidated sediments increase with increasing hydrate format
... Show MoreObjectives: to assess the normal range of different lip parameters with gender difference and its role in esthetic procedures for Iraqi people. Methods: direct lip measurements were performed with closed lip position using a digital vernier caliper in 132 young Iraqi subjects (89 female and 43 male). Results: Lip measurements showed sexual dimorphism with higher value in men than women in six parameters. Cutaneous height of the upper lip was higher in both sexes. The mustache area in males was longer in males compared to females. Also, it was noticed that upper lip vertical thickness had a higher value, especially in subjects with cosmetic procedures. In addition to that, vertical upper lip thickness showed a higher rise in values
... Show MoreBackground: The purpose of this study is to evaluate the care of multiple trauma victims with maxillofacial injuries in terms of epidemiological distributions, types of injuries, the related different modalities of surgical treatments delivered, and their complications. Materials and Methods: This prospective study was performed on 50 patients with multiple traumas including maxillofacial injuries, caused by different etiological factors, who were brought first to the surgical emergencies department of the Medical City then referred to the Maxillofacial unit in the Specialized Surgeries Hospital, Baghdad, Iraq, during the period from April 2007 to April 2008. Information was documented prospectively from the time of the emergency call to
... Show MoreKE Sharquie, AA Noaimi, ZT Burhan, Journal of Cosmetics, Dermatological Sciences and Applications, 2016 - Cited by 9
Collagen triple helix repeat containing-1 (CTHRC1) is an essential marker for Rheumatoid Arthritis (RA), but its relationship with pro-inflammatory, anti-inflammatory, and inflammatory markers has been scantily covered in extant literature. To evaluate the level of CTHRC1 protein in the sera of 100 RA patients and 25 control and compare levels of tumour necrosis factor alpha (TNF-α), interleukin 10 (IL-10), RA disease activity (DAS28), and inflammatory factors. Higher significant serum levels of CTHRC1 (29.367 ng/ml), TNF-α (63.488 pg/ml), and IL-10 (67.1 pg/ml) were found in patient sera as compared to that in control sera (CTHRC1 = 15.732 ng/ml, TNF-α = 33.788 pg/ml, and IL-10 = 25.122 pg/ml). There was no significant correlation be
... Show MoreBackground: The aim of this study was to evaluate the expression of fibroblast growth factor-2 and Heparanase in salivary pleomorphic adenoma, and to correlate the two studied markers with each other and with clinicopathological parameters including: age, sex, tumor site and histopathological presentation. Methods: Sections of twenty five formalin-fixed paraffin embedded tissue blocks specimens of salivary pleomorphic adenoma were immunostained using monoclonal antibodies (Fibroblast growth factor-2 and Heparanase) to assess their expression in this tumor. Results: The expression of fibroblast growth factor-2 and Heparanase were positive in all pleomorphic adenoma cases (100%). The positive expression of fibroblast growth factor-2 was signi
... Show MoreObjective: To evaluate whether the SOX2 protein could be used as a predictor in patients with GC and to assessment the correlation between the IHC expression of the SOX2 protein and the various clinic pathological Parameters as age, sex, histopathological subtypes, grade and stage of the tumor by immune-histochemical Technique. This is a retrospective study conducted on 60 randomly selected patients (30) normal versus (30) GC, at the pathology department of the Gastroenterology and Hepatology Teaching Hospital & some private hospitals. It were collected and diagnosed during the period between from 2014 to 2018. From each block were stained with H&E and IHC stained for SOX2. The Statistical analysis was done using SPSS system, and the differ
... Show MoreCarbon fiber reinforced polymers (CFRP) were widely used in strengthening reinforced concrete members
in the last few years, these fibers consist mainly of high strength fibers which increase the member capacity in addition to changing the mode of failure of the reinforced concrete beams. Experimental and theoretical investigations were carried to find the behavior of reinforced concrete beams strengthened by CFRP in shear and bending. The experimental work included testing of 12 beams divided into 4 groups; each group contains 3 beams. The following parameters were taken into consideration: - Concrete crushing strength. - CFRP strengthening location (shear strengthening and both shear and flexure strengthening). Reinforced beams were