Abstract:Purpose: This study aimed to assess how the material and base design of orthodontic brackets affect the shear bond strength (SBS) when bonded to a provisional polymethyl methacrylate PMMA crown. Methods: Fifty provisional PMMA maxillary crowns were fabricated and divided into five groups based on the orthodontic brackets used: Group 1: Bionic®, Group 2: Discreet™, Group 3: Radiance™, Group 4: Symetri®, and Group 5: Translux®. After surface treatment with 9.6% hydrofluoric acid, brackets were bonded. Each study group was subdivided into three subgroups according to artificial water ageing protocols used: baseline (24 h), 5000 thermocycles and 10000 thermocycles. SBS was tested and failure mode was analyzed. Statistical analysis included two-way ANOVA, and Tukey's post-hoc test (P < 0.05). Results: Radiance™ exhibited the highest SBS values under all aging conditions. Bionic® showed the second-highest SBS. Discreet™, Symetri™, and Translux® showed significant decreases in SBS values after ageing. ARI scores indicated that “Index 0” and “Index 1” significantly increased after ageing particularly for Discreet™, Symetri®, and Translux® orthodontic brackets. Conclusion: Radiance™ demonstrated superior SBS and durability compared to other brackets. However, caution is advised when using Radiance™ on PMMA crowns, as their SBS exceeds the clinically acceptable range.
Abstract:This paper analyses the progress and impacts achieved after their implementation both globally and in Georgia. The work mainly uses the qualitative method of research, which is divided into 2 stages: the analysis of secondary sources and in-depth interviews. In the case of Georgia, the main emphasis in the research was made around the renewable energy sector, because at this stage the country has one of the biggest prospects of getting closer to the sustainable development model through the development of a specific field. As a result of the research, it was confirmed that, as well as specifically in the context of Georgia, as well as on a global scale, the implementation of sustainable development goals in activities is hindered by low awareness in society. As for the impact on business, research has shown that specific concepts have a uniquely positive impact on both the private sector and the quality of life in general. Specifically, in the case of Georgia, the gaps in the involvement and readiness of the state institutions were highlighted. Achieving the goals set in a specific direction requires the involvement of each individual and the maximum understanding of the existing perspectives and needs in order to effectively and powerfully implement the goals in the activities, which will give you a relevant impact on the business and the quality of life in general.
Abstract:Objectives: This study compared the efficacy of the XP-endo retreatment (XPER) system in removing TotalFill HiFlow BC (Bioceramic) and TotalFill BC sealers from dentinal walls to that of the ProTaper Universal retreatment (PTUR) system using micro-computed tomography (micro-CT) analysis. Materials and methods: Forty human-extracted single-rooted mandibular premolars were decoronated, and the roots were randomly divided into two main groups of 20 according to the retreatment system used (PTUR or XPER), and each group was divided again into two subgroups (n = 10) based on the sealer type used (TotalFill HiFlow BC or TotalFill BC). All root canals were instrumented and obturated. After two weeks, the retreatment procedure was performed using both systems. All specimens were scanned with a micro-CT device after obturation and again after retreatment, and the volume of root-filling material removed was measured. One-way analysis of variance and independent t-tests were used for statistical analysis. Results: XPER removed 88% � 14.57% of the root canal filling material in the apical third, which was significantly (p = 0.000) more than that removed by PTUR (62.7% � 24.95%). Overall, XPER removed significantly more HiFlow BC (94.66% � 10.75%) than conventional BC sealer (92.66% � 10.31%). Conclusions: XPER was more efficient than PTUR in the BC sealer retreatment at the apical root third. Moreover, the use of HiFlow BC sealer with continuous wave obturation made the retreatment easier as compared with conventional BC sealer with single cone obturation.
Abstract:The 2nd International Conference on Computational & Applied Physics (ICCAP�2023) was held from October 8th to 10th, 2023. This conference was organized by the Laboratory of Physical-Chemical Inorganic Materials and their Applications (LPCMIA) at Blida1 University, within the Faculty of Sciences, Physics Department, in Algeria.
Abstract:Growing concern of carbon dioxide emissions, greenhouse effects and rapid depletion of fossil fuels raise the necessity to produce and adopt new eco-friendly sustainable alternatives to the internal combustion engine driven vehicles. For this reason, in the last decade, electric vehicles have become in some way widespread, principally because of their negligible flue gas emissions and lesser reliance on oil. Although electric cars were introduced many years ago, agriculture electric vehicles have recently gained attention. The world of agriculture has changed, small specialized farm utility vehicles are now used for a specific purpose, and in several cases they have an electric engine. In our research, we focused on the design and preparation of a prototype the variable, multifunctional ecological electric loader, which would be dimensionally adapted to the needs of use in greenhouse, interior growing halls, as a result of research by students of innovative dual technical education with effective support of their teachers. The research deals with specifically the solution of aluminium welding by the TIG method, because the prototype frame is the welding of aluminium parts. The result of our research was the design and construction of a prototype of a smaller electric loader, which meets demanding quality parameters (performance) and environmental attributes (reduced noise and almost zero emissions) for work in greenhouses. The benefit of our research is the design and actual implementation of a prototype of a different ecological �green� electric loader, which is still missing on the market in the agricultural sector and is the output of creative innovative technical education in the environment of secondary vocational schools
Abstract: Groundnut is an important cash crop and a diet component for rural households in sub-Saharan Africa. However, Aflatoxin contamination remains a barrier to promoting groundnut-based food products as food levels above maximum limit (ML) can adversely affect human health. Three objectives were set, namely, (i) to characterize the post-harvest operations and risk factors affecting aflatoxin contamination, (ii) to assess aflatoxin incidence in on-farm stores and, iii) to assess agronomic practices that can be integrated to improve yield and reduce aflatoxin contamination. The average aflatoxin levels in on-farm stores ranged from 11.3 to 16.4μg/kg, and the proportions of ML were 25.7% at 4μg/kg, 56.3% at 15μg/kg and 80% at 20μg/kg (~5 to 7 months after harvest). The application of Aflasafe® reduced aflatoxin contamination to safe level across the locations. Postharvest operations showing significant hazards include intermittent rain at harvest and drying (6.5), insect pests attacks after harvest (6), prolonged harvest to stripping interval (6.6), drying on bare ground (6.2), storing on bare floor (6.9), use of low efficient shelling machines (6.5) and re-use of rejected nuts (6.1). The potential increase of pod yield when best practices were adapted was in order of Triple Super Phosphate fertilizer (25.6-84.2%), YaraLegume fertilizer (18.4 to 52.7%), Rhizobium inoculant (14.6 to 45.8%) and Aflasafe® (5.5 to 43.1%). This study provides solutions to minimize aflatoxin risk if appropriate technologies (e.g. improved variety, fertilizer, Rhizobium inoculant, and Aflasafe®) and policies are deployed. In addendum, good drying and storage conditions are significant to optimizing benefits from good agronomic practices. Interventions to address cost limitations which hinder the adoption of these technologies require critical policy consideration.
Abstract:This research aimed to assess the effectiveness of a plyometric training regimen in improving agility, speed, and social interaction among boys with mild intellectual disability (ID) aged 10-12, within the context of the Special Olympics. The study involved thirty-two boys (average age = 10.69 ± 0.8 years; average IQ = 61 ± 7) from three inclusive education centers. Over a period of 10 weeks, participants engaged in a plyometric training program twice a week. Evaluations were conducted before and after the intervention using the Reaction Time Test, 4-Corner Agility Test, 10-Meter Speed Run, 4x5 Meter Relay Test, and the Friendship Activity Scale (FAS). Significant improvements were observed across all measures. Reaction time decreased by 0.83 seconds (t = 7.44, p < 0.001), agility improved by 0.77 seconds (t = 11.93, p < 0.001), 4x5 meter speed increased by 0.61 m/s (t = 17.37, p < 0.001), and 10-meter run speed improved by 1.55 m/s (t = -12.76, p < 0.001). Furthermore, the FAS score rose by 0.81 points (t = 9.59, p < 0.001), indicating a boost in social interactions.The plyometric training program significantly enhanced agility, speed, and social interaction in children with mild intellectual disability, demonstrating its efficacy as an inclusive physical education strategy within the Special Olympics framework.
Abstract:AIMS Copper nanoparticles (CuNPs) etch and rinse (ER) adhesive on the survival rate of Streptococcus mutans (S.mutans) micro tensile bond strength (μTBS) and Degree of conversion (DC) with carious dentin. METHOD Mandibular teeth with carious lesions were included. S.mutans were inoculated on CAD. Samples were allocated based on the application of Opti Bond FL primer modified with CuNPs in different concentrations. Group 1: Unmodified ER adhesive, Group 2: 0.1wt% CuNPs+ER adhesive, Group 3: 0.5wt% CuNPs+ER adhesive, and Group 4: 1wt% CuNPs+ER adhesive. Samples inoculated with S.mutans underwent evaluation of their survival rates. Samples were restored and underwent μTBS and failure mode assessment. DC was assessed using FTIR. Statistical analysis was conducted using ANOVA and Tukey test to evaluate significant differences across groups in terms of antibacterial potency, μTBS of ER adhesive, and DC RESULTS Group-4 (1wt%CuNPs+ER) treated teeth exhibited the minimum bacterial survival. Group-1 (Unmodified ER adhesive) showed maximum scores S.mutans survival. The highest bond of composite to the CAD was observed in Group-3 (0.5wt % CuNPs + ER adhesive) samples. μTBS was found to be lowest in Group-1 CONCLUSION CuNPs to an etch and rinse adhesive system at a concentration of 0.1wt% is a practicable way to provide adhesive interfaces with antimicrobial activity while also improving μTBS.
Abstract:The purpose of this study is to investigate the relationship of the silk of Seres and the wild silkworm silk made by Bing-Yi Dong-Yi people of the East. The BingJam, BingGeum, and Bing-Yi were studied through knowledge of textiles type and wild silk JakJam fibers through cross-checking of Eastern and Western records. We investigated who Bing-Yi, the first silk weaver, were, and found that Bing-Yi people used 5-colored BingJam fibers of wild silkworm in WonGyo mountain of current Shandong to weave BingGeum brocade from about BC 2,300. BingJam was identified as JakJam or CheonJam when are harvested in fall, and Bing-Yi was called Pung-Yi and Ram-Yi as the people among Dong-Yi of GoJoseon Gu-Yi. The place where the first silk was produced was not India nor the center Jina, but the Dong-Yi in the Far East. And the jade sculptures in the shape of silkworm from Hongshan culture and Geum silk piece excavated from the Wiyoungja area are unrefutable evidences. Seres people were the Yuezhi, a capital or a part of Ma(k)Han among the Sam(k)Han GoJoseon, and they exported not only their silk brocade with sericin remains, but also the quality iron produced in Jin/Byeon(k)Han, and the luxury patterned furs which were the famous products of Bal Joseon.
Abstract:Fiber-reinforced polymer composites offer numerous advantages over conventional materials, due to their better specific strength and stiffness. The service conditions and manufacturing process of the laminated plate are the causes of delamination which is a critical issue that needs to be addressed. Localized stress increases in and surrounding the delaminated zone if incipient delamination is not detected and stopped. This accelerated delamination process, driven by localized stress, ultimately leads to the failure of the composite structure. Therefore, it is imperative to explore the dynamic characteristics of delaminated composite structures. This study focuses on assessing the impact of delamination at various interfaces on the vibration characteristics of composite square plates composed of multiple plies. It also investigates how factors such as the shape, severity, and location of delamination affect the vibration properties of the composite plate. The modal analysis results obtained from a Finite Element (FE) model created using ABAQUS software are compared and validated against analytical and experimental findings from prior literature. Additionally, an analytical model used for finite element modeling of the composite plate is presented. The findings reveal that modal parameters of delaminated plates can serve as valuable indicators for identifying the shape, severity, and location of delamination.