Objectives: To review the failure rates of molar tubes and the effect of molar tube base design, adhesive type, and bonding technique on the failure rates of molar tubes. Data: The revolution of molar bonding greatly impacted fixed orthodontic appliance treatment by reducing chair-side time and improving patient comfort. Even with the many advantages of molar bonding, clinicians sometimes hesitate to use molar tubes due to their failure rates. Sources: Internet sources, such as Pubmed and Google Scholar. Study selection: studies testing the bond failure rate of molar tubes. Conclusions: The failure rate of the molar tubes can be reduced and the bond strength of the molar tubes can be improved by changing the design of the molar tube base

    Saccharin is firstly synthesized in 1879. It is a very well-known as an inexpensive substitute for sugar as it is a non-caloric sweetener. The article shows the properties, use, metabolism and various synthesis and reactions of saccharine. Moreover, the toxicological reports explain that saccharin is mostly responsible for the bladder tumors observed in the male rats, the relationship between the consumption of saccharin and bladder cancer is afforded by epidemiological studies.  The benefit-risk evaluation for saccharin is hardly to indicate. Saccharin is a sugar substitute, frequently used either in food industry, or in pharmaceutical formulations and even in tobacco products. The chemistry of saccharin is inter

Directional control valves are designed to control direction of flow, while actuators maintain required speeds and precise positions. Magnetorheological (MR) fluid is a controllable fluid. Utilizing the MR fluid properties, direct interface between magnetic fields and fluid power is possible, without the need for mechanical moving parts like spools. This study proposes a design of a four-way three-position MR directional control valve, presents a method of building, and explains the working principle of the valve. An analysis of the design and finite elements using finite element method of magnetism (FEMM) software was performed on each valve. The magnetic circuit of the MR valve was analyzed and the performance was simulated. The

To create a highly efficient photovoltaic-thermal (PV-T) system and maximise the energy and exergy efficiency, this study aims to propose an innovative configuration of a PV-T system comprising wavy tubes with twisted-tape inserts. Following the validation of a numerical model, a parametric study has been conducted to assess the geometrical effects of twisted tape and wavy tubes, as well as the coolant fluid type and velocity, on the overall performance of a PV-T system, located in Shiraz, Iran. It is found that employing twisted tape improves the energy and exergy efficiency by approx. 6.3%. The best configuration yields 12.4% and 16.8% increase in energy and exergy efficiency compared to conventional PV systems. This is achieved at 15% vo

New series of metal ions complexes have been prepared from the new ligand [4-Amino-N-(5-methyl-isaxazol-3-yl)-benzenesulfonamide] derived from Sulfamethoxazole and 3-aminophenol. Accordingly, mono-nuclear Mn(II), Fe(III), Co (II), and Rh(III) complexes were prepared by the reaction of previous ligand with MnCl₂.4H₂O, CoCl₂.6H₂O, FeCl₃.6H₂O and RhCl₃H₂O, respectively. The compounds have been characterized by Fourier-transform infrared (FTIR), ultraviolet–visible (UV–vis), mass,  ¹H-, and ¹³C-nuclear magnetic resonance (NMR) spectra and thermo gravimetric analysis (TGA& DSC) curve, Bohr magnetic (B.M.), elemental microanal

تركت العولمة المتسارعة أثرا عميقا على مدى واسع من السياسات والتطبيقات الاقتصادية في كل من الدول النامية والمتقدمة على حد سواء, إذ نشأت الأنظمة الضريبية الحالية عندما نمّط كل بلد سياسته الضريبية بشكل تركز معه على متطلبات الاقتصاد المحلي, وعندما كانت تعقد المفاوضات بين الأمم المختلفة حول المعاملات الضريبية والاتفاقات الضريبية كانت تجري في إطار من هيمنة السياسة الضريبية المحلية.

لكن العولم

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 .

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RÉSUMÉ                                                    

            LeMauger Bleu est une méthode emblématique de l’enseignement traditionnel, qui présente une littérature française riche et patrimoniale, et dont l’objectif est de faciliter l’accès au texte par le vocabulaire et la grammaire et d’étendre la culture générale et littéraire de l’apprenant. La démarche (traditionnelle) est toujours la même : le texte, le vocabulaire et la grammaire, la traduct

عرض كتاب (وهم التحكم : القوة والسياسة الخارجية في القرن الحادي والعشرين)