Background: Thermocycling simulates the temperature dynamics in the oral environment. This in vitro study done to measure and compare the effect of thermocycling on the shear bond strength of stainless steel and sapphire brackets bonded to human enamel teeth using light cured orthodontic adhesive and debonded at various time, and to measure adhesive remnant index after debonding. Materials and Methods: one-hundred-twenty extracted upper first premolars for orthodontic reason were used in this study; depending on weather thermocycled or not, the sample was divided into two main groups, then within each group 30 teeth were used for stainless-steel brackets (Bionic®) and for sapphire brackets (Pure®). Both groups were subdivided into three

     In this work, the switching nonlinear dynamics of a Fabry-Perot etalon are studied. The method used to complete the solution of the differential equations for the nonlinear medium. The Debye relaxation equations solved numerically to predict the behavior of the cavity for modulated input power. The response of the cavity filled with materials of different response time is depicted. For a material with a response time equal to = 50 ns, the cavity switches after about (100 ns). Notice that there is always a finite time delay before the cavity switches. The switch up time is much longer than the cavity build-up time of the corresponding linear cavity which was found to be of the order of a few round-trip ti

ملخص البحث تنوعت اساليب وطرائق التدريب بشكل واسع وكبير وتعددت الاهداف التدريبية تبعا لخصوصية الاداء في النشاط الرياضي الممارس، وكل هذا جعل امام العاملين في الانشطة الرياضية كم كبير من الحلول لمواجهة المشاكل التي تواجههم في اثناء الاعداء للرياضيين، وتعد التمرينات المركبة واحدة من الاساليب التنظيمية للتمرين التي تضم في محتواها تعدد الاداءات خلال التمرين الواحد مما يتيح للاعب تطبيق متطلبات بدنية او مهارية ا

Background: Sperm motility disorder is an important cause of infertility in male, and one of the causes of reduced motility of the sperm is the disorders of the mitochondria because it provides the required energy for sperm motility, Laser biostimulation or low-level laser therapy has a positive effect on the mitochondria and led to increasing the synthesis of ATP. Method: Twenty fresh human semen samples were used in this research study, each sample was separated into two portions, one was used as control which is not exposed to the laser beam and the other was irradiated with the wavelength of 410 nm diode laser with an output power of 100 mW and an exposure time of 60 seconds, then the measurement of

Occupies total quality management applications play a key role in the development of institutions of higher education performance and achieve its strategic objectives through the commitment of senior management and their employees to continuous improvement of the quality of performance in the various areas of work, and can be integrated knowledge management processes, which means identifying information of value and how to take advantage. The data were collected using the style of the questionnaire for the purpose of analyzing their results on a sample composed of 83 member of the administrative leadership in colleges as representing the decision-making centers in those colleges . 

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Recent research has examined the improvement of physical and dielectric properties of BaTiO₃ ceramic material by small addition of excess TiO₂ or BaCO₃. The prepared samples sintered at different temperatures and varying soaking time. The results show that increasing the sintering temperature within 1350°C and soaking time of 10 hrs give better electrical and physical properties, which indicate the reaction is complete at higher temperature and period.

The optical absorption data of Hydrogenated Amorphous Silicon was analyzed using a Dunstan model of optical absorption in amorphous semiconductors. This model introduces disorder into the band-band absorption through a linear exponential distribution of local energy gaps, and it accounts for both the Urbach and Tauc regions of the optical absorption edge.Compared to other models of similar bases, such as the O’Leary and Guerra models, it is simpler to understand mathematically and has a physical meaning. The optical absorption data of Jackson et al and Maurer et al were successfully interpreted using Dunstan’s model. Useful physical parameters are extracted especially the band to the band energy gap , which is the energy gap in the a

         Interested in this research shed light on the reality of foreign trade to Iraq Who suffers from a marked deterioration due to poor economic diversification of the country And increase the degree of economic exposure   , Which creates a state of extreme caution towards the question of accession to the (WTO)   , As controls Iraq's foreign trade commodity  , a president of one oil As well as the contribution of this item  , and by a large formation in GDP   , And that such a large and dangerous decline in the degree of economic diversification will create negative effects On overall economic activity components&