The standard formulation of Wave Intensity Analysis (WIA) assumes that the flow velocity (U) in the conduit is <;<; the velocity of propagation of waves (c) in the system, and Mach number, M=U/c, is negligible. However, in the large conduit arteries, U is relatively high due to ventricular contraction and c is relatively low due to the large compliance; thus M is > 0, and may not be ignored. Therefore, the aim of this study is to identify experimentally the relationship between M and the reflection coefficient in vitro. Combinations of flexible tubes, of 2 m in length with isotropic and uniform circular cross sectional area along their longitudinal axes, were used to present mother and daughter tubes to produce a range of reflection coefficients. An approximately semi-sinusoidal pulse was generated at the inlet of the mother tube using a syringe pump, first in the condition of initial velocity, U 0 =0, and when U 0 >0 with steady flow to superimpose the pulse. Pressure (P) and Velocity (U) were measured in the mother tube, wave speed was determined using the foot to foot and PU-loops methods. The theoretical reflection coefficient, R t at M=0, has been compared to the experimental reflection coefficient, R at M>0, which was determined as dP-/dP+ as calculated using WIA. The function R(M) changes significantly with the geometrical and mechanical features of the connected tubes. In our experiments, R increased significantly with small values of M. In the range of M=0-0.02, R increased by 4-36%. Therefore, we conclude that M significantly affects the magnitude of reflections.
Background: Atrophic postoperative and traumatic scarring are common cosmetic problems for patients. Combining CO2 laser ablation with a fractional photothermolysis system in a treatment known as ablative fractional resurfacing fulfilling the new demands for a lesser risk of side effects and minimal or no downtime.Objective: To assess the safety and efficacy of ablation fractional CO2 laser treatments for surgical scarring .methods: Twenty one patient ( 14 women, and 7 men ) with various skin types , I to IV , aged 3 to 48 years , presents with 24 scars between June and December 2012 , four patients excluded from study because they are not continued in follow up , the remaining 17 patient completed all 3 treatments & 6 months follow
... Show MoreFor the past few years, the sediment began to accumulate in Al-Gharraf River which reduces the flow capacity of the River. In the present research, a numerical model was developed using Hec-Ras software, version 5.0.4. to simulate the flow and sediment transport in the upper reach of the river. The hydrological and cross-section data measured by the Ministry of Water Resources, for the reach located between Kut and Hai cities and having a length of 58200 m, was used to perform calibration and verification of the model. Moreover, field sampling of suspended and bed loads was gathered for five months starting from 7/2/2019, and laboratory tests of samples were conducted to be used as in
This study evaluates 22 patients with retained foreign bodies in the maxillofacial region that were all caused by penetrating missile injuries. Surgical intervention for the retrieval of the foreign bodies was carried out in 20 patients through the existing wounds and through separate incisions; all patients were followed up for a minimum of 2 months during which all the complications were registered and managed. Preoperative imaging is a prerequisite for the accurate localization of the foreign body and the subsequent successful removal of it. All patients developed complications that were categorized in this study into those that result from the injury itself and those that occur because of the retrieval procedure, the latter category bei
... Show MoreThis study was conducted to test the hypothesis that the duration of time spent by the student inside the examination rooms answering the all kinds of written ex-amination questions has some kind of a positive effect on the final score he will get from that exam. And if there arc gender differences in this respect. Students and methods: Data on the final examinations of the autumn quarter was gathered on 892 examina-tions conducted at the end of this quarter , this included male participants of 566 and females of 326. Examinations were on twenty different subjects , including all of the first five years of the undergraduate students of Iraqi College of Medicine for the academic year 2002 — 2003 . The scheduled time of the examinations was
... Show MoreThe present study aimed to examine the effect of endosulfan insecticide on some molecular and biochemical parameters in white mice. Thirty mice were separated randomly into three groups for treatment with endosulfan. One group (G1) served as the control, while the other two groups received intraperitoneal injections of endosulfan G2 (3 mg/kg) and G3 (17 mg/kg) twice a week for 21 and 45 days, respectively. A biochemical study by measuring liver function parameters, including (alanine aminotransferase (ALT) and aspartate aminotransferase (AST)) and kidney function parameters, including (Blood Urea and Creatinine) and malondialdehyde (MDA), catalase activity (CAT). This study also tested DNA damage by comet assay (normal%, low%, med
... Show MoreFinancial inclusion refers to the access of financial services at low cost and high-quality from the formal financial sector to all segments of society, especially marginalized groups, and then use and benefit from them. Financial inclusion is also associated with banking stability, as well as with financial integrity and financial protection for the consumer, therefore, it achieves a number of objectives, the most important of which is to support and enhance banking stability. This is what made it attract the attention of many countries and central banks recently.
The study aims to show the impact of financial inclusion indicators on ban
... Show MoreBalad –Rooz is considered as one of the endemic foci of Schistosomiasisin Iraq.A survey was performed during the first three months of 2002 in fewprimary schools in Balad –Rooz to assess the prevalence among them.
This study aimed to identify the alterations of liver in the quail (Coturnix coturnix) exposed by nanosilver particles.45 quail (females) were collected from agriculture research center in Abu-Ghraib, divided into (6) groups including: T1(12 quails were exposed to 4ppm), T2 (12 quails were exposed to 8ppm) and T3 (12 quails were exposed to 12ppm) of silver nanoparticles solution for 60 days. As well as three groups for control (3 females for each). Birds were dissected to isolate livers for histological preperations after fixation with Bouin's fluid, Routine stains Hematoxyline and eosin were used. Histological study showed that the structure of liver in a control groups consist of hepatocytes arranged radially cords around the central vein
... Show MoreThere are main methods of scientific research, and that the researcher's choice of the appropriate methodology for scientific research is one of the most important rules on which the researcher must rely in order to prepare scientific research properly. There is no doubt that the methodology of scientific research is of great importance that they all agree on the preparation of accurate scientific research. Scientific research is an organized research that does not come by chance, but comes as a result of the activity of the mind. It is theoretical because it relies on theories for the purposes of perceiving the proportions and relationships between things, and everyone is subjected to testing and experiment.