It is found that hypersensitive teeth have a larger number and wider patent tubules than those of non-sensitive teeth. Objective: The aim of this study is to compare between the effects of diode laser at different power densities, with and without sodium fluoride on the sealing of exposed dentinal tubules and dentin permeability. Materials and methods: 118 teeth were used. Samples were divided into three major groups. The first consisted of 100 teeth used for permeability test. The second consisted of 16 teeth for measuring external surface temperature elevation while irradiation. The third, in turn, consisted of one pair of teeth observed under SEM for dentine surface morphology analysis. Results: For dentin permeability measurement, the results revealed a highly significant difference between the control group and 2, 3 W with varnish groups. For the external surface temperature elevation, the results revealed that temperature rise, for both laser alone and with varnish groups, was between (67-97.9 ∘C) at 1.6, 2 W. SEM analysis revealed that approximately optimum sealing of tubules occurred in 2W with the varnish group. Conclusions: The combined application of 940 nm diode laser at 2W with 809.7 W/cm² power densities, with sodium fluoride white varnish show a significant improvement in their effects on dentin permeability reduction as compared to each treatment alone.
Thyme essential oil (TEO) was extracted from dried leaves of Thymus vulgaris. The air-dried aerial parts of the plant produced 1.0% yield of TEO. The detection of this essential oil’s compounds was performed by GC-MASS. The cytotoxic activity of TEO was evaluated against two human cancer cell lines, namely HeLa (human epithelial cervical cancer) and MCF-7 (human breast carcinoma). Cells grown in 96 multi-well plates were treated with six concentrations of EO (6.25, 12.5, 25, 50, 100, 200 ppm) and incubated at 37 °C for 72 hrs. Cancer cell lines elicited various degrees of sensitivity to the cytotoxic effect of essential oil. The TEO exhibited significant differences (p≤ 0.01) between the effects of
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(3)
In this study, simple, low cost, precise and speed spectrophotometric methods development for evaluation of sulfacetamide sodium are described. The primary approach contains conversion of sulfacetamide sodium to diazonium salt followed by a reaction with p-cresol as a reagent in the alkaline media. The colored product has an orange colour with absorbance at λmax 450 nm. At the concentration range of (5.0-100 µg.mL-1), the Beer̆ s Low is obeyed with correlation coefficient (R2= 0.9996), limit of detection as 0.2142 µg.mL-1, limit of quantification as 0.707 µg.mL-1 and molar absorptivity as 1488.249 L.mol-1.cm-1. The other approach, cloud point extraction w
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يهدف البحث إلى تحقيق عدد من الأهداف: الكشف عن مدى تفاعلية الجمهور إزاء استخدام التطبيقات الإعلانية في الفضائيات عبر أجهزة الهاتف المحمول. التعرف على تفضيلات الجمهور بين التطبيقات. الوقوف على أهم الموضوعات التي يفضل الجمهور التفاعل معها في التطبيقات الإعلانية. الكشف عن أبرز المعوقات التي تواجه مستخدمي التطبيقات الإعلانية في الفضائيات عبر الهاتف المحمول. الوقوف على مدى مساهمة التطبيقات الإعلانية في الفضائي
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إن التغيرات السريعة والبعيدة المدى في تكنولوجيا المعلومات القائمة على أساس الالكترونيات الدقيقة تساعد في حدوث تحول في صورة الاقتصاد العالمي، وكذلك تساعد في تغيير المزايا التنافسية للبلدان، وربط المؤسسات البعيدة ببعضها البعض، ونشر الخدمات المالية على نطاق عالمي، وكذلك إثارة مشكلات جديدة او العكس فتح فرص جديدة أمام تنمية ونمو أفقر البلدان .
وأدت هذه التكنولوجيا الجديد
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The principal components analysis is used in analyzing many economic and social phenomena; and one of them is related to a large group in our society who are the university instructors. This phenomenon is the delay occurred in getting university instructor to his next scientific title. And as the determination of the principal components number inside the principal components depends on using many methods, we have compared between three of these methods that are: (BARTLETT, SCREE DIAGRAM, JOLLIFFE).
We concluded that JOLLIFFE method was the best one in analyzing the studying phenomenon data among these three methods, we found the most distinguishing factors effecting on t
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Design sampling plan was and still one of most importance subjects because it give lowest cost comparing with others, time live statistical distribution should be known to give best estimators for parameters of sampling plan and get best sampling plan.
Research dell with design sampling plan when live time distribution follow Logistic distribution with () as location and shape parameters, using these information can help us getting (number of groups, sample size) associated with reject or accept the Lot
Experimental results for simulated data shows the least number of groups and sample size needs to reject or accept the Lot with certain probability of
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كثيرة هي البحوث والدراسات التي نراجعها في السلوك التنظيمي، بحكم عملنا كأستاذ دراسات عليا بتخصص ادارة الموارد البشرية ونظرية المنظمة، ووقع بيننا بحثاً نظرياً متميزاً للباحثين
(Karin Sanders & Birgit Schyns)([1])، نشر في مجلة اصيلة هي (Personnel Review)، في عام (2006)، بمجلدها (35) وبالعدد (5)، تحت عنوان (Trust, Conflict and Cooperative Beha
The current study was conducted to evaluate the effect a mixture of threespecies of arbuscular mycorrhizal fungi (Glomus etunicatum, G. leptotichum andRhizophagus intraradices) double and triple mixture and organic matter by usingplastic pots in the greenhouse at some mycorrhiza and physiological limitationscharacteristics in tomato plant after four and eight weeks of cultivation. Theresults of the determinants mycorrhiza significant increase the percentage ofmycorrhizal frequency F% dry weight of roots mycorrhiza (g.plant-1) andorganic matter in all mycorrhiza single, double and triple mixture after four andeight weeks cultivation treatments. The highest percentage of mycorrhizalfrequency and increase the dry weight of the root in the trea
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Abstract
Due to the momentum of winning in the streets of the city of Baghdad as a result of the large number of checkpoints so felt researcher to conduct a field visit to find out the main reasons that led to this congestion and to find practical solutions to mitigate wastage winning the arrival time citizen to where you want the least possible time.
This research aims to overcome the difficulties experienced by citizens to reach their places of work and reduce waste at the time of service and waiting time as well as reduce the cost of waiting.
Has emerged study a set of conclusions, including the use of model queue (G / G / C) and the mome
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