Background: Debonding orthodontic brackets and removal of residual bonding material from the enamel surface include critical steps that may cause enamel damage. The aim of the present study was to evaluate and compare the site of bond failure and enamel surface damage after debonding of three types of esthetic brackets (composite, ceramic, sapphire) bonded with light cure composite and resin-modified glass ionomer adhesive. Materials and methods: Seventy two maxillary premolars teeth were divided into three groups each group consisted of 24 teeth according to the type of brackets. Each group was subdivided into two subgroups (12 teeth for each) according to the bonding material that was used. After 7 days of bonding procedure, the brackets

Three new polyphosphates were synthesized in good yields by reacting diethylenetriamine with the appropriate phosphate ester in ethanol under acidic conditions. The polyphosphate structures were determined using FT-IR and 1H-NMR spectroscopies, and their elemental compositions were confirmed by EDX spectroscopy. Polyphosphates were added to poly(vinyl chloride) (PVC) at low concentrations to fabricate thin films. The PVC films were irradiated with ultraviolet light for long periods, and the effect of polyphosphates as the photostabilizer was investigated by determining changes in the infrared spectra (intensity of specific functional group peaks), reduction in molecular weight, weight loss, and surface morphology. Minimal changes we

The conservation of natural resources such as water is one of the areas that sustainable agriculture seeks to preserve, rationalize its use and protect it from pollution, because water is a specific factor for agriculture. Despite Iraq's possession of two international rivers, the Tigris and the Euphrates, which pour into the Shatt Al-Arab, it suffers from water shortages in recent times, As a result of several reasons combined, including water policies initiated by the riparian countries to reduce the quantities of water coming from the two rivers to Iraq, led by neighbor Turkey through the construction of dams and reservoirs and the establishment of irrigation projects, as well as climate changes from rising temperatures and lo

The impact of undergraduate research experiences on students' academic development and retention in STEM fields is significant. Students' success in STEM fields is based on developing strong research and critical thinking skills that make it essential for students to engage in research activities throughout their academic programs. This work evaluates the effectiveness of undergraduate research experiences with respect to its influence on student retention and academic development. The cases presented are based on years of experience implementing undergraduate research programs in various STEM fields at Colorado State University Pueblo (CSU Pueblo) funded by HSI STEM Grants. The study seeks to establish a correlation between students' reten

     In this article, a new efficient approach is presented to solve a type of partial differential equations, such (2+1)-dimensional differential equations non-linear, and nonhomogeneous. The procedure of the new approach is suggested to solve important types of differential equations and get accurate analytic solutions i.e., exact solutions. The effectiveness of the suggested approach based on its properties compared with other approaches has been used to solve this type of differential equations such as the Adomain decomposition method, homotopy perturbation method, homotopy analysis method, and variation iteration method. The advantage of the present method has been illustrated by some examples.

تعدُّ القارة الإفريقية ذات موقع جيوسياسي إذ إنه يربط دول العالم بعضها ببعض، وأنّها تحتوي على ثلث الاحتياط النفطي المؤكد العالمي واليوريانيوم والمعادن الأخرى مما جعلها ذات أهمية للدول العظمى، وأنّها غير مستقرة سياسياً إذ تكثر بها النزعات والهجمات الإرهابية مما جعل الدول العظمى تتسابق لوقف المشاكل، ومن أهم هذه الدول العظمى هي فرنسا التي تحتفظ بنفوذها السبق أي الاستعماري في القارة وأنّها لا تتنازل عنه لأي دو

Acquisition of metacognition has an effective and important role in educational process, so it can reduce difficulties faced by learners during theirunderstanding of the subjects.

Brown (1980) considers that it is conscious and reflective controlcarried out by the individual in his actions and cognitive responses through the use of self-regulation skills (planning, monitoring and evaluation).

The search problem raises through following question: Havestudents  ofhigh school for distinct metacognition?

Metacognition is very important  , so the effective learninginvolves planning and goalsetting, and monitoring the progress of the individual and adapted as needed, and allthese activities are metacognition i

يعد الصراعات الدولية ظاهرةقديمة قدم البشرية وعلى المستوى الدولي وغالبا ما تكون الدول الصغرى هي الساحة لتصفية الصرااعت بين الدول الكبرى كما هو الحال في سوريا مما يؤدي لعدوم وجود امن انساني فيها

Human beings are under the threat of the environment they are living in. With the course of time, they seriousness of this threat and its effect in changing their life . The most common threat that human beings might pass through is the trauma which is commonly bound with wars. The greater trauma that human beings might have is the threatening sudden facing or death facing. Consequently there would be disorder especially War disorder. This Phenomenon is clearly observed in Iraqi society as Iraq has been passing through continuous wars and disasters namely during and after the American Invasion. These events might lead to changes in Peoples  behavior and to Social Violence. Thus, the Study aims at:

ان العلاقة ما بين الحكومة المركزية واقليم كردستان يحكمها نوعا من مظاهر التوتر الذي يتعلق بالاختصاصات الموزعة ما بينهما، والمشكلة الاساسية ذات علاقة بالتأويل الدستوري، فمنذ العام 2003 ومروراً بالإعلان الدستوري ونحن نعاني من قضية شائكة وهي ما الصلاحيات التي تتمتع بها الحكومة المركزية قياسا بالصلاحيات التي يتمتع بها اقليم كردستان، وتوزيع الثروات والموارد الطبيعية وغيرها من المسائل الخلافية بين ممثلي الكتل ال