Background: Elastomeric chains are used to generate force in many orthodontic procedures, but this force decays over time, which could affect tooth movement. This study aimed to study the force degradation of elastomeric chains. Data and Sources: An electronic search on Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, LILACS, and PubMed was made, only articles written in English were included, up to January 2022.Study selection: Fifty original articles, systematic reviews, and RCTs were selected. Conclusion: Tooth movement, salivary enzymes, alcohol-containing mouthwash, whitening mouthwash, and alkaline and strong acidic (pH <5.4) solutions all have a significant impact on elastomeric chain force degradation. The force level of elastomeric chains degrades rapidly over time; however, the force degradation rate is slower in thermoset chains than in thermoplastic ones. An efficient tooth movement could be achieved by using a thermoset chain type with monthly replacement. Ethylene oxide and gamma sterilization methods are preferred to avoid the risk of cytotoxicity.
Worldwide, enormous amounts of waste cause major environmental issues, including scrap tires and plastic, and large waste, a consequence of the demolition of buildings, including crushed concrete, crushed clay bricks, and crushed thermo-stone. From that point, it’s possible to consider that the recycling processes for these materials and using them in the manufacturing field will reduce the adverse effects on the environment of these wastes and the consumption of natural resources. Sustainable concrete blocks can be considered as one of the products produced by using these materials as partial volume replacement of the coarse, fine aggregate, or cement content, considering their dry density, workability, absorption, compressive st
... Show MoreConstruction projects are characterized as projects with multi phases and activities, complex, unique, and have many different parties and stakeholders. Risks could appear at one or more of the construction project stages and may affect the achievement of project objectives. Therefore, one of the key elements in the planning phase of any project is the risk management process (RMP). This study attempts to understand the terminology of risk in general, risk management, and response to risk in particular. This study is mainly a review of thirty-eight studies that have been published between 1997 and 2020 that demonstrate the importance of the crucial phase of risk response from the risk management process and its impact on
... Show MoreThe 2000 Nobel Prize in Chemistry was awarded to Alan J. Heeger, Alan G. MacDiarmid, and Hideki Shirakawa for the discovery and development of conductive polymers, particularly polyacetylene. Since then, research on conducting polymers has progressed rapidly, with sustained focus on their morphology, structural design, and technological applications. This paper presents a comprehensive review of conducting polymers, focusing on their structure, synthesis, and applications in electrical, optical, and energy-conversion technologies. Prominent systems – including polyaniline, polypyrrole, polythiophene, polyacetylene, poly(p-phenylene vinylene) (PPV), poly(p-phenylene) (PPP), and poly(3,4-ethylenedioxythiophene) (PEDOT) – are discussed wit
... Show MoreBegan research of the foundations of Orientalist discourse based on force and metadata and authority, and the possibility of turning the West's view of the East as if made radical changes in the structure of the West or in a relationship of power and authority between it and the east. We have adopted in our paper on the research categories of Edward Said and visions in the field of Orientalism in general, and especially his book entitled the name of this area, not forgetting, or leave the expansion to other sources, a researcher in this field, to enrich the research.
We went to Orientalism as a concept and based cognitive, and the work of the Orientalist, and the meanings of Orientalism, which suggests Balastala which was c
... Show MoreThe evaluation of assignment problems for job suppliers is necessary to meet demands; therefore, academics in the operations research field and management factories have paid considerable attention to assignment problems. Notably, because the central point of classical assignment models with parameters assumes that supplier management oversees all inputs and outputs are fixed data, these types of models cannot provide exact and accurate data. Hence, specific inputs and/or outputs can be improper and ambiguous. Consequently, existing studies have explored various approaches to determine an optimal route that corresponds to assignments to suppliers when ambiguous values are involved. However, the computation of multiple routes for each assign
... Show Moreيهدف هذا البحث الى التطرق الى صورة العربي كما يعرضها ادب اليافعين العبري في رواية " نادية " للكاتبة العبرية " كاليلا رون فيدر " . والتي تعد من الاديبات العبريات اللواتي تطرقن بصورة مباشرة الى موضوع ما خلف الجدار ، والصراع العربي – الإسرائيلي وانعكاساته على المجتمع الإسرائيلي بصورة عامة والمجتمع العربي بصورة خاصة . ينقسم هذا البحث إلى ثلاثة فصول، تطرق الفصل الأول إلى "ادب اليافعين"، و تاريخه ، مميزاته والفئ
... Show MoreThroughout what mentioned above, It is obvious that the aware narrator in these biography models was the strongest tool in presenting the content, especially the biographies under study were written by feminine hands, striving to prove her identity by all means and ways. In addition, we can suppose that the hiding of she writer behind the character is no more than a mask, by which she want to mask herself so that she can express herself frankly and freely, especially when she talks about subjects that are inconsistent with the society, customs and traditions. It is important to refer that the existence of the participant narrator in the biographies under study does not prevent the presence of another narrator such as external or aware na
... Show MoreIncreasing requests for modified and personalized pharmaceutics and medical materials makes the implementation of additive manufacturing increased rapidly in recent years. 3D printing has been involved numerous advantages in case of reduction in waste, flexibility in the design, and minimizing the high cost of intended products for bulk production of. Several of 3D printing technologies have been developed to fabricate novel solid dosage forms, including selective laser sintering, binder deposition, stereolithography, inkjet printing, extrusion-based printing, and fused deposition modeling. The selection of 3D printing techniques depends on their compatibility with the printed drug products. This review intent to provide a perspecti
... Show MoreIn present days, drug resistance is a major emerging problem in the healthcare sector. Novel antibiotics are in considerable need because present effective treatments have repeatedly failed. Antimicrobial peptides are the biologically active secondary metabolites produced by a variety of microorganisms like bacteria, fungi, and algae, which possess surface activity reduction activity along with this they are having antimicrobial, antifungal, and antioxidant antibiofilm activity. Antimicrobial peptides include a wide variety of bioactive compounds such as Bacteriocins, glycolipids, lipopeptides, polysaccharide-protein complexes, phospholipids, fatty acids, and neutral lipids. Bioactive peptides derived from various natural sources like bacte
... Show More