ABSTRACT Background: Bracket rebonding is a common problem in orthodontics which may result in many drawbacks. The aims of this study were to evaluate the effects of application of two enamel protective agents “Icon” and “ProSeal” on shear bond strength before and after rebonding of stainless steel orthodontic brackets using conventional orthodontic adhesive and to assess the site of bond failure. Materials and methods: Fifty sound extracted human upper first premolar teeth were selected and randomly divided into two equal groups; the first time bonding and the rebonding groups (n=30). Each group was subdivided into control, Icon and ProSeal subgroups. The enamel protective agents were applied after etching (precondi

The research deals with the principle of the prohibition of international waterway diversion in the law of international watercourses. The research reviews individual and collective doctrinal efforts that have touched upon the principle as an internationally wrongful act because of its serious damage and consequences for downstream States. The research addresses the nature of the principle of the prohibition of diversion of international watercourses; its various effects; principles of international law establishing the principle of prohibition of diversion; and its application in State practice and international justice. This principle has been enshrined in most international treaties and judicial decisions. The principle of prohibition

Attitude is an important subject that has attracted researchers and thinkers in organizational theory and organizational behavior because of its great importance in various field studies. Field evidence suggests that individuals in their daily lives or careers respond to specific events through a set of internal tendencies Internal tendencies are negative or positive and systematic. These trends tend to be invisible, not limited to certain boundaries, and involve a significant number of individuals within organizations or society.

 The research aims to identify the impact of trends in the ethics of public service workers for individuals, through a sample of (72) doctors and (60) administrative staff

The filler in the asphalt mixture is essential since it plays a significant role in toughening and stiffening the asphalt. Changes in filler type can lead the asphalt mixtures to perform satisfactorily during their design life or degrade rapidly when traffic and environmental effects are considered. This study aims to assess the impact of filler types such as limestone dust (LS) and hydrated lime (HL) on Marshall characteristics and moisture damage in asphalt mixtures. Three different percentages of HL were employed in this study to partially replace the LS mineral filler: 1.5, 2.0, and 2.5% by aggregate weight. Furthermore, a control mixture was created with 7% LS by overall aggregate weight for the wearing course layer. The Marsha

This experiment was performed to investigate the effect of dietary supplementation with linseed on egg quality of laying quail. A total of 320 9-week-old Japanese quail (Coturnix coturnix japonica) 9-wk old were allocated to 4 treatment groups with 4 replicates containing 20 quail each. Birds were fed a commercial diet containing 0% (C), 2% (T1), 4% (T2), or 6% (T3) linseed. Birds received water and diet ad libitum during the total period of the experiment. Egg quality characteristics were monitored over 3 consecutive 21-d periods. Egg quality criteria involved in this experiment were egg weight, yolk diameter, yolk height, yolk weight, albumen height, albumen weight, shell weight, shell thickness, Haugh unit, albumen percentage, yolk perce

Porous silicon (P-Si) has been produced in this work by photoelectrochemical (PEC) etching process. The irradiation has been achieved using diode laser of (2 W) power and 810 nm wavelength. The influence of various irradiation times on the properties of P-Si material such as P-Si layer thickness, surface aspect, pore diameter and the thickness of walls between pores as well as porosity and etching rate was investigated by depending on the scanning electron micrograph (SEM) technique and gravimetric measurements.

This study investigates the ionic conduction dependence on the size of alkaline cations in gel polymer electrolytes based on double iodide can enhance by incorporating a salt having a bulky cation.

Moisture induced damage can cause a progressive deterioration in the performance of asphalt pavement by the loss of adhesion between asphalt binder and aggregate surface and/or loss of cohesion within the binder in the presence of water. The objective of this paper is to improve the asphalt mixtures resistance to moisture by using hydrated lime as an anti-stripping additive. For this purpose, two types of asphalt binder were utilized; asphalt grades (40-50) and (60-70) with one type of aggregate of 19.0 mm aggregate nominal maximum size, and limestone dust as a mineral filler. Marshall method was adopted to find the optimum asphalt content. Essentially, two parameters were determined to evaluate the moisture susceptibili

This study was conducted according to contract with the North Refineries Company-Baiji and deals with the hydrodesulphurization of vacuum gas oil of Kirkuk crude oil, boiling range 611-833 K. A trickle bed reactor packed with a commercial cobalt-molybdenum on alumina catalyst was used. The operating conditions were: temperature range 583-643 K, liquid hourly space velocity range 1.50-3.75 1/h, hydrogen to oil ratio about 250 l/l and pressure kept constant at 3.5MPa.
The results showed that the aromatic content decreased and sulfur removal increased with increasing temperature and decreasing space velocity. The properties (viscosity, density, flash point and carbon residue) of the products decrease with temperature increasing, but the

Asphalt binder is a thermoplastic material that conducts as an elastic solid at lower service temperatures or throughout fast loading rate. At a high temperature or slow rate of loading, asphalt binder conducts as a different liquid. The classical duplication generates a required to assess the mechanical properties of asphalt concrete at the anticipated service temperature to reduce the stress cracking, which happens at lower temperatures, fatigue, and the plastic deformation at higher temperatures (rutting). In this study, an achievement was made to assess the effect of temperature on the mechanical characteristics of asphalt concrete mixes. A total of 132 asphalt concrete samples were attended utilizing two asphalt cement grades (40-50) a