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 incubation media (distilled water and acid challenge); each 16 bracket-archwire combinations were tested 6 times by Instron testing machine under wet conditions. Polycrystalline ceramic brackets combined with 0.014-inch NiTi rhodiumcoated archwires produced significantly low mean static frictional force in an acidic environment. Furthermore, no significant mean static frictional forces difference between monocrystalline and polycrystalline ceramic brackets if combined with 0.014 of an inch NiTi ilusio or 0.019 x 0.025 of an inch SS rhodium coated archwires. Conclusion: Coupling polycrystalline ceramic brackets with 0.014 of an inch NiTi rhodium coated rather than ilusio archwires in an acidic environment is advisable. At the same time, it is wise to combine with polycrystalline ceramic brackets the 0.019 x 0.025 of an inch SS ilusio archwires in distilled water rather than to combine with monocrystalline brackets
The marketing logistic chain, as an integrated system aimed to balance the achievement of its main opposite objectives which represented in the access to the best service presented to the customer with lowest possible logistic costs especially the transportation costs, where encourages the researcher to choose the second objective as a field of this study in order to reduce the transportation costs in the final link of marketing logistic chain which related to delivering of fuel oil to the customer that falls within organizational responsibilities of the company under consideration (Oil Marketing Company) and also known in a brief name by (SOMO) through two methods, the first is by functioning quantative techniques by using trans
... Show MoreDensity Functional Theory at the generalized-gradient approximation level coupled with large unit cell method is used to simulate the electronic structure of (II-VI) zinc-blende cadmium sulfide nanocrystals that have dimensions 2-2.5 nm. The calculated properties include lattice constant, conduction and valence bands width, energy of the highest occupied orbital, energy of the lowest unoccupied orbital, energy gap, density of states etc. Results show that lattice constant and energy gap converge to definite values. However, highest occupied orbital, lowest unoccupied orbital fluctuates indefinitely depending on the shape of the nanocrystal.
Nisoldipine (NSD) is a dihydropyridine class of calcium channel blockers used for hypertension treatment, it belongs to class II BCS (low solubility with high permeability), its absolute bioavailability is only 5% due to presystemic metabolism in the gut wall. It is also a substrate for a CYP3A and P-gp. Bilosomes are lipid bilayer vesicles incorporating bile salts in their walls to prevent degredation by GIT bile salts. The aim of this study is to prepare nisoldipine bilosomes as vesicular carrier and assess the effect of different formulation variables such as type of surfactant, amount of cholesterol, surfactant and sonication time on particle size, entrapment efficiency and poly dispersity index of the prepared bilos
... Show MoreIn this study, the effect of the thermal conductivity of phase change material (PCM) on the performance of thermal energy storage has been analyzed numerically. A horizontal concentric shell-and-tube latent heat thermal energy storage system (LHTESS) has been performed during the solidification process. Two types of paraffin wax with different melting temperatures and thermal conductivity were used as a PCM on the shell side, case1=0.265W/m.K and case2=0.311 W/m.K. Water has been used as heat transfer fluid (HTF) flow through in tube side. Ansys fluent has been used to analyze the model by taking into account phase change by the enthalpy method used to deal with phase transition. The numerical simulatio
... Show MoreThe interest in Multi social skills and self-concept is extremely important for many of the scholars of education and psychology has taken a great deal in their writings and their interests as they see that social skills training is to make sure of the same, and that whenever enable the individual from acquiring social skills whenever asserted itself.The research aims know social skills and self-concept and their relationship to the children Riyadh age (4-6 years), and the research sample consisted of(200) boys and girls from kindergarten in the city of Baghdad Bjanbey Rusafa second and Karkh second.And to the objectives of the research realized the researcher has built two measures of social skills a
... Show MoreThe fluctuations in oil prices in world markets affect the general budget and the trade balance of the rent countries, because oil is a strategic commodity affected by economic and political factors. The fluctuations in oil prices affect the public budgets of the rent countries through the public revenue side of oil revenues. On the other hand, these fluctuations affect the balance of trade through the volume of oil exports, which lead to imbalance of trade surplus or deficit . &nbs
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This research aims to identify the challenges faced by families of children with intellectual disabilities and to identify the impact of the challenges facing them on the mental health of their children with intellectual disabilities. Based on the following questions: What is the nature of the challenges faced by families of children with disabilities and how do these challenges affect the mental health of their children with intellectual disabilities? The study was conducted on a sample of four families of six children with intellectual disabilities, depending on the degree and type of disability. To achieve the study's objectives, the qualitative approach was used, Because of the importance of accessin
... Show MoreA chemometric method, partial least squares regression (PLS) was applied for the simultaneous determination of piroxicam (PIR), naproxen (NAP), diclofenac sodium (DIC), and mefenamic acid (MEF) in synthetic mixtures and commercial formulations. The proposed method is based on the use of spectrophotometric data coupled with PLS multivariate calibration. The Spectra of drugs were recorded at concentrations in the linear range of 1.0 - 10 μg mL-1 for NAP and from 1.0 - 20 μg mL-1 for PIR, DIC, and MEF. 34 sets of mixtures were used for calibration and 10 sets of mixtures were used for validation in the wavelength range of 200 to 400 nm with the wavelength interval λ = 1 nm in methanol. This method has been used successfully to quant
... Show MoreThe present study aimed to investigate the possible production of Thioflavin T and the effect of NaCl concentrations and growth phases on the growth rate, doubling time and proline of C. saipanensis N. Hanagata (Scenedesmaceae, Shaerophleales). The alga was cultured in BG 11 medium and six NaCl concentrations were used in the experiments during different growth phases. The results have unveiled the presence of Triflavin T in the alga. The study results showed a growth rate decrease at all NaCl concentrations except in control treatment, while the doubling time, was recorded highest value (14 days) at the NaCl concentration of 0.08 M. The highest value of Proline (0.509 mg. Lˉ¹) was recorded at the treatment of 0.08 M of NaCl and recorded
... Show MoreIt is through a review of conversion of vegetable oils into glycidyl ethers focusing on their roles in achieving sustainability and improved epoxy resin performance. It involves functionalization of triglycerides in the form of epoxidation followed by glycidylation and yields bio-based monomers having improved mechanical as well as thermal properties. The review covers the underlying chemistry, production drivers, industrial applications, and future issues, supported by quantitative data and comparative studies. In addition, it integrates recent data on catalyst choice, feedstock flexibility, and environmental performance factors of bio-based resins, indicating their suitability for replacing traditional petroleum-based components.<
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