Orthodontic treatment is widely used to correct irregular teeth and/or jaw discrepancies to improve oral function and facial aesthetics. However, it is frequently associated with enamel damage that include chipping, demineralisation, and white spot formation. So far, current bonding systems that can maintain shear bond strengths (SBS) suitable for clinical performance are unable to limit enamel demineralisation, adhesive remnants and damage caused on removal of brackets after treatment. This study reports a novel “safe enamel etch” clinically viable procedure that was accomplished via application of novel etchant pastes developed with β-tricalcium phosphate and monocalcium phosphate monohydrate powders mixed with citric acid (5 M) or phosphoric acid (37% PA) to yield BCA and BPA etchants respectively. Although enamel etched with clinically used PA gel yielded higher SBS than the BCA/BPA etchants, it exhibited greater adhesive remnants with evidence of enamel damage. In contrast, the experimental etchants resulted in unblemished enamel surfaces with zero or minimal adhesive residue and clinically acceptable SBS. Furthermore, the BPA etchant caused lower enamel decalcification with extensive calcium-phosphate precipitation. The study conclusively showed that BPA facilitated
Hydrogels are hydrophilic biocompatible polymers that can be used as a drug delivery material in different medical branches, including vital pulp therapy. The aim of this study is to characterize the physical and biological properties of the newly developed formula as a candidate direct pulp-capping material. The hydrogel composite was prepared from natural and synthetic origins (polyvinyl alcohol (PVA), hyaluronic acid (HA), and sodium alginate (SA)) with the incorporation of bioactive Moringa. Different formulas of hydrogel containing different concentrations were evaluated for physicochemical (FTIR, XRD, SEM, degradation, and swelling), mechanical (viscosity, folding endurance, film thickness), and biological (antioxidant, antibacterial,
... Show MoreIn this study, aluminum alloyAA6061-T6 was joined by a hot press process with three types of material; polyamide PA 6.6 (nylon), 1% carbon nanotube/PA6.6 and 30% carbon fiber/PA6.6 composites. Three parameters were considered in the hot pressing; temperature (180, 200 and 220°C), pressure (2, 3, 4, 5 and 6 bar) and time of pressing (1, 2, 3, 4 and 5 minutes for 200ºC, and 0.25, 0.5, 0.75, 1 and 1.25 minutes for220ºC). Applied pressure has great effect on shear strength of the joint, corresponding to bonding time and temperature. Maximum shear strength was 8.89MPa obtained for PA6.6 at bonding conditions of 4 bar, 220ºC and 0.75 minute. For 30% carbon fiber/PA6,6 shear recorded was
Ruthenium-Ruthenium and Ruthenium–ligand interactions in the triruthenium "[Ru3(μ-H)(μ3-κ2-Hamphox-N,N)(CO)9]" cluster are studied at DFT level of theory. The topological indices are evaluated in term of QTAIM (quantum theory of atoms in molecule). The computed topological parameters are in agreement with related transition metal complexes documented in the research papers. The QTAIM analysis of the bridged core part, i.e., Ru3H, analysis shows that there is no bond path and bond critical point (chemical bonding) between Ru(2) and Ru(3). Nevertheless, a non-negligible delocalization index for this non-bonding interaction is calculated
... Show MoreThe operation and management of water resources projects have direct and significant effects on the optimum use of water. Artificial intelligence techniques are a new tool used to help in making optimized decisions, based on knowledge bases in the planning, implementation, operation and management of projects as well as controlling flowing water quantities to prevent flooding and storage of excess water and use it during drought.
In this research, an Expert System was designed for operating and managing the system of AthTharthar Lake (ESSTAR). It was applied for all expected conditions of flow, including the cases of drought, normal flow, and during floods. Moreover, the cases of hypothetical op
... Show MoreThis paper presents the implementation of a complex fractional order proportional integral derivative (CPID) and a real fractional order PID (RPID) controllers. The analysis and design of both controllers were carried out in a previous work done by the author, where the design specifications were classified into easy (case 1) and hard (case 2) design specifications. The main contribution of this paper is combining CRONE approximation and linear phase CRONE approximation to implement the CPID controller. The designed controllers-RPID and CPID-are implemented to control flowing water with low pressure circuit, which is a first order plus dead time system. Simulation results demonstrate that while the implemented RPID controller fails to stabi
... Show MoreThe discourse surrounding lingual sovereignty within the African postcolonial context is profoundly intertwined with the fabric of cultural identity and self-determination. Language serves not merely as a conduit for communication but as a repository for a people's collective consciousness, encapsulating their traditions, thoughts, and perspectives. In the realm of postcolonial literature, this dialogue often grapples with the paradox of expressing indigenous narratives through the linguistic tools of former colonizers. Chinua Achebe's seminal work, "Things Fall Apart," exemplifies this conundrum, artfully weaving the orature and culture of Umuofia within the English language. Achebe's choice to write in English—a language imposed upon hi
... Show MoreIn recent days, the escalating need to seamlessly transfer data traffic without discontinuities across the Internet network has exerted immense pressure on the capacity of these networks. Consequently, this surge in demand has resulted in the disruption of traffic flow continuity. Despite the emergence of intelligent networking technologies such as software-defined networking, network cloudification, and network function virtualization, they still need to improve their performance. Our proposal provides a novel solution to tackle traffic flow continuity by controlling the selected packet header bits (Differentiated Services Code Point (DSCP)) that govern the traffic flow priority. By setting the DSCP bits, we can determine the appropriate p
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