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Article
Estimating the Stability of Orthodontic Micro-implant after Applying Orthodontic Force "An Experimental in Vivo Study"

Author: Estimating the Stability of Orthodontic Micro-implant after Applying Orthodontic Force "An Experimental in Vivo Study"
Journal: Al-Rafidain Dental Journal مجلة الرافدين لطب الأسنان ISSN: 18121217 Year: 2013 Volume: 13 Issue: 1 Pages: 154-161
Publisher: Mosul University جامعة الموصل

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Abstract

Aims: To evaluate weather micro-screw implants remain stationary or move against orthodontic forces during different healing periods (immediate loading, loading after 2 weeks and 4 weeks). Materials and Methods: Thirty micro-screw implants were implanted in 6 rabbits. These rabbits divided into 3 groups (2 in each group). The first group received loading immediaty after implantation. The second and third groups received loading after 2 weeks and 4 weeks of healing period respectively. The stabil-ity of these implants was measured using periotest device before and after loading. The data was ana-lyzed using descriptive statistic, Analysis of variance (ANOVA), Duncan Multiple analysis range test and student t-test. Result: Among the three groups, the first group having a significant greater stability of micro-screw implants immediately before and after loading and after 2 weeks of loading period. Conclusion: micro-screw implants can be loaded immediately after implantation with light orthodontic force; also these implants can be loaded after 4 weeks of healing period.


Article
SPECTROPHOTOMETRIC MICRO DETERMINATION OF DRUG

Author: Fadhil Jasim
Journal: Al-Fatih journal مجلة الفتح ISSN: 87521996 Year: 2005 Volume: 1 Issue: 22 Pages: 54-65
Publisher: Diyala University جامعة ديالى

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Abstract

The drug desferrioxamine mesylate (DFOM) forms with vanadium (v) a colored chelate (λ max = 460 nm) complex at pH – range (1- 1.34 ) which is extractable with Benzyl alcohol as organic solvent . Under the appropriate experimental conditions a calibration plot was set up from which some analytical parameters were derived and deduced by regression .Standard additions procedure was also adopted .It has been estimated that the concentration of the drug DFOM to be 487.6 mg per unit and 485.1 mg per unit for both calibrations. Under optimal conditions, the developed method has been achieved the following characteristics: LDR (2.0 – 275 μ g ml -1) DFOM, RSD % (0.3- 0.45), sandell sensitivity (0.158 μ g. cm-2), LOD (0.5 μ g ml -1), recovery %(101.466 ± 0.763), Erel %(1.466). stability constant ( 2.1x 107 M -1).The mole – ratio method ( 1:1) approved that DFOM V (v) as a structure of the complex. The developed procedure has been adapted to analyze DFOM in various pharmaceuticals.


Article
Influence of Shape Design of MEMS (Micro-Cantilever Based Sensor) on High-Sensitivity
تاثیر تصمیم شكل المستشعر الكابولي الادق على زیادة التحسس

Author: Ibtissam Mahdi Shihab
Journal: Engineering and Technology Journal مجلة الهندسة والتكنولوجيا ISSN: 16816900 24120758 Year: 2012 Volume: 30 Issue: 20 Pages: 3581-3595
Publisher: University of Technology الجامعة التكنولوجية

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Abstract

In this paper, a novel analysis was carried out on the biosensor microcantileversin order to increase the sensitivity of a micro- cantilever basedbiosensor piezoresistive. Holes were made and compared with the basicrectangular (R), triangular (T), and step(S) profile cantilever. Effect of changingthe micro-cantilevers profile and its cross-section shape was investigated. A finiteelement ANSYS was used to analyze these models. The micro-cantilevers aremade of silicon with elastic modulus 130Gpa and poisson’s ratio 0.28. Severalcases were studied by making one, two and three holes in each biosensorpiezoresistive micro-cantilevers (rectangular (R), triangular (T), and step(S) profilecantilever). Results showed that triangular micro-cantilever with two holes (T22)has the better sensitivity, also showed T12 respectively 61.7% and 65% highersensitivity than R12, S12.

لغ رض (Micro-Cantilever based sensor ) فى ھذا البحث تم اجراء تحلیل مبتك ر عل ىزیادة التحسس من خلال عمل ثقوب دائریھ فى عتبات المستش عر الت ي ھ ى بمقط ع مس تطیل مثل ثومتدرج. لغرض اجراء المقارنھ بینھما من خ لال دراس ة ت اثیر تغی ر مقط ع ش كل العتب ھ عل ى اداء130 و نسبة بویسن 0.28 Gpa المستشعر .و تم استخدام مادة السلیكون والذي لھ معامل المرونةت م دراس ة ع دة .ANSYS لتص نیع المتحسس ات ولغ رض تحلی ل ھ ذه النم اذج ت م اس تخدام طریق ةح الات م ن خ لال وج ود ثق ب واح ده او ثقب ان او ثلاث ة ثق وب ف ى ك ل م ن المق اطع الثلاث ھ مثل ث،م ع (T مستطیل ومتدرج. اظھرت نتائج الدراسھ بان العتبھ ( المستشعر ) ذات المقطع المثلث( 22، R اكث ر بالتت ابع م ن 12 (T وجود ثقب ان ھ ى الاكث ر تحس س للاجھ ادات واظھ رت ایض ا ب ان( 12ةبسنب % 61.7 و % 65 ھى الاكثر تحسس للاجھادات. S12


Article
Optimizing Overcut Parameter of Micro-Holes Machining by EDM Using Taguchi Method
إیجاد عامل تجاوز القطع المثالي في التشغیل بالشرارة الكھربائیة للثقوب الدقیقة باستخدام طریقة Taguchi

Authors: Laith A. Mohammed --- Shukry H. Aghdeab
Journal: Engineering and Technology Journal مجلة الهندسة والتكنولوجيا ISSN: 16816900 24120758 Year: 2014 Volume: 32 Issue: 2 Part (A) Engineering Pages: 298-304
Publisher: University of Technology الجامعة التكنولوجية

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Abstract

In this paper Taguchi method was performed to estimate the optimum overcut parameter for Electro Discharge Machining (EDM) to obtain micro-holes of copper alloy workpieces. Taguchi method is used to formulate the experimental layout, to analyses the effect of each parameter on the machining characteristics and to predict the optimal choice for each machining parameter (current, gap distance and machining time), and analyzed the effect of these parameters on the overcut parameter. Theanalysis shows that, the current significantly affects the overcut parameter.

في هذه المقالة تم استخدام طريقة تاجاشي لتقدير القيمة المثلى لعامل تجاوز القطع للتشغيل بالشرارة الكهربائية للحصول على ثقوب دقيقة لعينات من سبيكة النحاس. استخدمت طريقة تاجاشي لصياغة النموذج التجريبي وتحليل تأثير كل متغير على الخصائص التشغيلية والتنبؤ بأمثل اختيار لكل متغير تشغيلي (التيار ، مسافة الفجوة وزمن التشغيل)، وتحليل تأثير كل متغير من هذه المتغيرات على عامل تجاوز القطع. اظهر التحليل ان التيار هو المؤثر الفعال على عامل تجاوز القطع.

Keywords

EDM --- Micro-Holes --- Taguchi Method


Article
Design and Implementation of a Line Follower Robot Based on Fuzzy Logic controller by Using Microcontroller
تصميم و تنفيذ الروبوت متتبع الخط بالاعتماد على مسيطر المنطق المضبب باستخدام المسيطر الدقيق

Author: Ahmed A. Radhi احمد علي راضي
Journal: Journal of Al-Ma'moon College مجلة كلية المأمون ISSN: 19924453 Year: 2016 Issue: 28 Pages: 288-303
Publisher: AlMamon University College كلية المامون الجامعة

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Abstract

Robot is widely used to help human to do something, especially for difficult or danger ous tasks. The robot requires, some techniques, sensors and controller have been. In this research robot movement is guided by. Fuzzy logic control as intelligent control applied to govern the robot follow line. Infrared sensors are used to sense line as the input variable for the controller. Based on these signals, the controller control the turning angle of forward movement thus making robot move forward and turning at the same time. A fuzzy logic control was selected for its robustness and flexibility.

استخدم الروبوت على نطاق واسع لمساعدة الإنسان على فعل الاشياء، وخاصة بالنسبة للمهمات الصعبة أو الخطرة, الروبوت يتطلب بعض التقنيات، وأجهزة للاستشعار و تطبيق المتحكم . تم في هذا البحث تطبيق المنطق الضبابي للتحكم الذكي في الروبوت متتبع الخط. واستخدمت أجهزة استشعار بالأشعة تحت الحمراء للاستشعار كمدخلات لوحدة التحكم. وبناء على هذه الإشارات، وحدة التحكم و السيطرة عملت على تحويل زاوية الحركة إلى الأمام وبالتالي جعل الروبوت يتحرك إلى الأمام، وتحويل الاتجاه في الوقت نفسه. وقد تم اختيار المنطق الضبابي لمتانة ومرونة عملة.


Article
The Effect of Green Tea Polyphenol (EGCG) on Orthodontic Micro-Implant Stability: An experimental study

Authors: Mustafa Muath Hamed Al-Sultan --- Zaid Salim Twafeeq
Journal: Journal of Oral and Dental Research مجلة طب الفم والاسنان ISSN: 23106417 Year: 2017 Volume: 4 Issue: 2 Pages: 102-109
Publisher: Iraqi Association for Oral Research الجمعية العراقية لبحوث طب الفم

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Abstract

Background Increasing the orthodontic micro-implant stability and enhancing bone response around it, is a fundamental objective of successful therapy. Materials and Methods Thirty orthodontic micro-implants, 1.3 mm in width and 5 mm in length (Dentos, AbsoAnchor, South Korea), were used with three implants were inserted in the right tibias of ten New Zealand rabbits, the rabbits categories into two groups, fve each. The primary stability was measured once the implant inserted, using Periotest. The experimental group fed (0.5% wt/vol/day) Green Tea, using the loading technique, for four weeks interval. At the end of the experimental period, the rabbits were sacrifced, and the secondary stability measurement was taken. Results Using paired t-test, the results showed a signifcant increase in secondary stability for the experimental group after four weeks experimental period when compared with the primary one. While the control group showed a non-signifcant increase in the secondary stability compared with the primary one. Conclusion This study concluded that the Green Tea could enhance bone response around orthodontic micro-implant within four weeks healing period and consequently increase the stability of orthodontic micro-implant

Keywords

Green Tea --- Micro-Implant --- Stability


Article
A Microleakage evaluation of Sonicfll, Silorane-based and nanofll methacrylate-based composites (a comparative study)

Authors: Muhanned A. AlHadad --- Hikmet A. Sh. AlGharrawi --- Jacob Y. Al-Hashemi
Journal: Journal of Oral and Dental Research مجلة طب الفم والاسنان ISSN: 23106417 Year: 2017 Volume: 4 Issue: 2 Pages: 120-129
Publisher: Iraqi Association for Oral Research الجمعية العراقية لبحوث طب الفم

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Abstract

Introduction Resin composites have been improved greatly nowadays, and many advancement has been reached. However, polymerization shrinkage is still a challenging drawback of composite resin restorations. Objectives this study was conducted with aim of comparing, in vitro, the marginal adaptation of three different, low shrinkages, direct posterior composites. Materials and Methods The following composites, Sonic fll® (nanohybrid composite), Filtek® P90 (Silorane-based composite) and Filtek® Z350 (nanofll composite) utilizing a standardized Class V cavity preparation followed by thermal cycling. Sixty human premolars prepared with standardized Class V cavities. The specimens were divided into three groups (n=20) according to the material used. All specimens were subjected to thermocycling at (5° to 55°C), then immersed in 2% methylene blue dye for 24hrs. For each group microleakage at the occlusal and gingival regions was measured by determining dye penetration using scoring system under steromicroscope at 100x. Results The statistical analysis of the results showed that, silorane-based composite exhibited the lowest microleakage, with statistical signifcant difference (p< 0.05) when compared with Sonicfll® composite and Filtek® Z350 XT nanofll composite. On the other hand, the results of this study showed non-signifcant difference between Sonic fll® composite and Filtek® Z350 XT. Also, there is a signifcant difference ( < 0.01) in dye penetration between occlusal and gingival regions within each group. Conclusion Taking into consideration the types of composites tested in this study, we recommend the clinical use of Siloran-based composite material for higher microleakage resistance and better marginal seal.


Article
MICRO-ENDOSCOPIC DISCECTOMY, A MODERN APPROACH FOR LUMBAR DISC PATHOLOGY

Authors: Mohamed El Husseini --- Taghrid Chaaban
Journal: Basrah Journal of Surgery مجلة البصرة الجراحية ISSN: 16833589 / ONLINE 2409501X Year: 2017 Volume: 23 Issue: 2 Pages: 26-33
Publisher: Basrah University جامعة البصرة

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Abstract

MICRO-ENDOSCOPIC DISCECTOMY, A MODERN APPROACH FOR LUMBAR DISC PATHOLOGYMohamed El Husseini* & Taghrid Chaaban@ *MD, PhD, Neurosurgeon, Hôpital Libano Français, Zahle, Lebanon. @MS Nursing, IUL, Beirut, Lebanon.Abstract In the last decade, the neuro-endoscope has been used increasingly in the surgical management of spinal diseases, both intradural and extradural. Endoscopic discectomy is increasingly performed in lumbar region. This study included 200 patients with lumbar disc pathology operated upon with both techniques: Classic and Endospine Karl Storz system technique introduced by Destandau. Based on results (Macnab modified criteria), microendoscopic discectomy should be used in properly selected patients.Key words: endoscopic, lumbar disc hernia, Endospine, Destandau technique


Article
A New Structure for Cascaded Single-Stage Distributed Amplifier Using Proposed Active Inductor Loads
هيكلة جديدة للمضخمات التوزيعية باستخدام احمال حثية فعالة

Author: Azad R. Kareem آزاد رحيم كريم
Journal: Al-Khwarizmi Engineering Journal مجلة الخوارزمي الهندسية ISSN: 18181171 23120789 Year: 2005 Volume: 1 Issue: 1 Pages: 19-25
Publisher: Baghdad University جامعة بغداد

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Abstract

A modification to cascaded single-stage distributed amplifier (CSSDA) design by using active inductor is proposed. This modification is shown to render the amplifier suitable for high gain operation in small on-chip area. Microwave office program simulation of the Novel design approach shows that it has performance compatible with the conventional distributed amplifiers but with smaller area. The CSSDA is suitable for optical and satellite communication systems.

البحث يتناول دراسة موجزة لمضخمات أشارات الترددات المايكوية ذات النطاق الواسع جدا باستخدام مبدا (Cascaded Single Stage Distributed Amplification) الذي يستخدم بشكل كبير في تطبيقات الاتصالات البصرية و انظمة الاتصالات عبر الاقمار الصناعية. هذا النوع من المضخمات يضم في تركيبته محاثات في دائرة الخرج. ان حجم المحاثة هو احد اهم المشاكل التي ترافق تصميم الدوائر المتكاملة (integrated circuits) للانظمة المايكروية, لذلك تم تطويرهذه التقنية من المضخمات بحيث اصبحت تستخدم نوع مستحدث من المحاثات سميت "محاثات فعالة" الهدف الاساسي منها هو انها تحتاج مساحة اقل عندما تصمم على الدوائر المتكاملة .التشكيل الجديد للمضخم أختبر باستخدام برنامج (Microwave Office) الذي هو مختص بالانظمة المايكروية وكانت نتائج الاختبار هو ان المضخم الجديد مطابق بكفائته للمضخم التقليدي مع فرق انه يحتاج حجوم اصغر للمحاثات .


Article
High Resolution Miniaturized Lens Arrays Scanners and Image Formation Systems For Medical Applications
تصميم منظومات مسح وتصوير عاليه التفريق ذات مصفوفات من العدسات المصغرة المايكروية للتطبيقات الطبية

Authors: Samira M. Arif --- Mohamed S. Ahmed --- Dayah N. Raouf
Journal: Engineering and Technology Journal مجلة الهندسة والتكنولوجيا ISSN: 16816900 24120758 Year: 2011 Volume: 29 Issue: 5 Pages: 871-885
Publisher: University of Technology الجامعة التكنولوجية

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Abstract

The optical design of miniaturized high resolution micro lens arrays systemsMLAs, for scanning and image formation, is achieved. The types of scanner systemsthat have been handled are microlens array MLA scanner system with f-number F#2.54, for two scanning angles. The one with higher scanning angle predicts theinfluence of increasing aberrations on the output. The imaging capabilities of singleand multiple array systems are presented. Their performance characteristics arestudied and analyzed to fit medical applications, the most important are compactnessand resolution. The overall size of the designed systems is a fraction of a centimeterand the resolution is in a few micrometers regime. However, it is found thatoptimizations are needed to enhance the quality of images, specifically for largerscanning angles.

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