Frictional resistance occurs whenever sliding happens, negatively impacting treatment outcomes and duration. It is a clinical challenge and must be dealt with efficiently to achieve the best orthodontic results. Aims of this study: compare and evaluate the static frictional forces under the wet condition to mimic the oral environment produced by using a polycrystalline ceramic bracket, monocrystalline ceramic bracket, 0.014 of an inch nickel-titanium (Rhodium coated archwires, and ilusio aesthetic archwires), and 0.019 x 0.025 of an inch stainless steel (Rhodium coated archwires, and ilusio aesthetic archwires). Ninety-six aesthetic brackets (48 monocrystalline and 48 polycrystalline brackets) were used and stored in different incub

Polyhydroxyalkanoates (PHAs) have gained much attention as biodegradable polymers, many efforts are being made to minimize the cost of PHAs by finding cheap carbon source depending on the type of microorganism and fermentation conditions. The aims of this study were to evaluate the effects of different glucose concentrations and other important conditions on the PHA production by Bacillus cereus isolated from soil. Polyhydroxyalkanoates PHAs accumulated by soil microorganisms were examined by screening the isolated bacteria using Sudan B Black and Nile Blue staining process. A Gram positive strain was identified using the 16s rRNA gene, deposited in the NCBI GenBank sequence database. Different growth conditions (favorite glucose concentrat

Corrosion experiments were carried out to investigate the effect of several operating parameters on the corrosion rate and corrosion potential of carbon steel in turbulent flow conditions in the absence and presence of sodium benzoate inhibitor using electrochemical polarization technique. These parameters were rotational velocity (0 - 1.57 m/s), temperature (30oC – 50oC), and time. The effect of these parameters on the corrosion rate and inhibition efficiency were investigated and discussed. It was found that the corrosion rate represented by limiting current increases considerably with increasing velocity and temperature and that it decreased with time due to the formation of corrosion product layer. The corrosion potential shifted t

The effect of applied current on protection of carbon steel in 0.1N NaCl solution (pH=7) was investigated under flow conditions (0-0.262 m/s) for a range of temperatures (35-55°C) using rotating cylinder electrode. Various values of currents were applied to protect steel from corrosion, these were Iapp.=Icorr., Iapp.=2Icorr. and Iapp.=2.4Icorr. under stationary and flow conditions. Corrosion current was measured by weight loss method. The variation of protection potential with time and rotation velocity at various applied currents was assessed. It is found that the corrosion rate of carbon steel increases with rotation velocity and
has unstable trend with temperature. The protection current required varies with temperature and it inc

We describe the synthesis and characterization of a novel 2D-MnOx material using a combination of HR-TEM, XAS, XRD, and reactivity measurements. The ease with which the 2D material can be made and the conditions under which it can be made implies that water oxidation catalysts previously described as “birnessite-like” (3D) may be better thought of as 2D materials with very limited layer stacking. The distinction between the materials as being “birnessite-like” and “2D” is important because it impacts on our understanding of the function of these materials in the environment and as catalysts. The 2D-MnOx material is noted to be a substantially stronger chemical oxidant than previously noted for other birnessite-like manganese oxi

Background: Acute abdominal pain classically refers to pain within the abdomen that has been present for less than 7 days from the time of presentation. The use of CT scan in the evaluation of acute abdominal pain has increased to a large extent due to high accuracy of CT in the diagnosis of specific diseases like appendicitis and diverticulitis, especially with the use of multidetector CT scanners. It has been shown that the use of intravenous contrast media increases the diagnostic accuracy of CT scan examination, with a positive predictive value of 95% in the cases of acute appendicitis. The accuracy of CT scan imaging in patients with acute abdominal pain was not affected by the lack of entral contrast material.
Objectives: To eva

       Field experiment was conducted during 2018- 2019 in loam soil at the research field of the Department of Biology, College of Science, Baghdad University, Baghdad, Iraq, to study the effect of bio-fertilizers and two levels of chemical fertilization ( 50% and 100%) in some agronomic traits of wheat Triticum aestivum L. cultivar IPA 99  by the genus Azotobacter chroococum and AMF Glomus mosseae singly or in combination under drought condition. The experimental design was a Completely Randomized Block Design (CRBD)with three replications. The results revealed that the application of bio-fertilizers reduced the negative impacts of water deficit. However, &nbsp

This paper presents an investigation to the effect of the forming speed on healing voids that inhabit at various size in an ingot. The study was performed by using finite element method with bilinear isotropic material option, circular type voids were considered. The closure index was able to predict the minimum press force necessary to consolidate voids and the reduction. The simulation was carried out, on circular cross-section lead specials containing a central void of different size. At a time with a flat die, different ratio of inside to outside radius was taken with different speed to find the best result of void closure.

 The adsorption of Ru and Ce were carried out using manganese dioxide as adsorbent. The Optimization of the adsorption conditions were studied as a function of shaking time, nitric acid, metal ions, concentrations and temperature effects.      A rapid initial adsorption on MnO2 is followed by a steady and slow increase of metal uptake. The equilibration time is reached after four hours shaking for Ru and Ce and    the adsorption is much better from one molar acidic solution and 90°C.

Fifty isolates of Bacillus sp. were subjected to the first and second screening to detect the ability to produce laccase enzyme and select the highest ones production of laccase on Petri plates containing nutrient agar supplemented with Cu2+.
Syringaldazine was used as an indicator and substrate for the determination of laccase activity. Three isolates, which consumed less time to developed pink color were tested for the production of laccase quantitatively. The effective isolate B16 with significant amounts of laccase 1.84 unit /ml was selected for laccase study.
The optimization studies revealed that the maximum laccase production was achieved when the production medium was at the following conditions: 5 days of incubation, tempe