Fluoride release and uptake abilities of different fissure sealants

Background: The long-term capability of resin sealants and glass ionomer cements to release fluoride is associated to a reduction in pit and fissure caries. The regular use of fluoride varnishes/toothpastes can result in the absorption of fluoride into the sealant. The objective of the present study was to assess the fluoride release/uptake capacities of different fissure sealants. Material and Methods: Three different fissure sealants (Fuji Triage/GC, Fissurit FX/Voco and Grandio Seal/Voco) were examined. Ten discs of each material were prepared. Each disc was incubated with distilled water and then the solution analyzed for diluted for fluoride concentration, using a combination of fluoride electrode (OrionGP 1 S/N 13824, Orion Research Inc, Boston, MA, USA) connected to an expandable ion analyzer (Orion 720A, Orion Research Inc, Boston, MA, USA). Standard curves between 1 and 100 ppm F- were used to calibrate the electrode. Cumulative fluoride release was measured on days 1, 2, 3, 5, 7, 21, 35 and 49, then two different fluoride varnishes/ pastes (Profluorid Varnish/Voco, MI Paste Plus/GC), were applied to the sealants tested, and fluoride release (after reuptake) was measured on days 56, 70 and 84. Results: Kruskal Wallis test confirmed significant differences in fluoride release between Fuji Triage/GC and Fissurit FX/Voco and Grandio Seal/Voco from day 1 ( P < 0.001). The application of fluoride varnish Profluorid Varnish enhanced the fluoride release for all sealants ( P < 0.05). MI Paste Plus enhanced the fluoride release for all sealants except for Fuji Triage/GC ( P > 0.05). Conclusions: The GIC-based sealant (Fuji Triage/GC) released significantly more fluoride than the resin sealants tested. The exposure to the fluoridated varnish (Profluorid Varnish) significantly recharged the sealants tested more than the CPP-ACPF toothpaste (MI Paste Plus)

KARAKTERISTIK AUDITOR, RISIKO AUDIT, DAN TANGGUNG JAWAB DALAM MENDETEKSI KECURANGAN

This study investigate the relation between auditor characteristics and audit risk with its responsibilities to detect fraudulent financial statements. This study predicts auditor independence, auditor competence and ethical awareness are positively related to auditor's responsibility to detect fraudulent financial statements. Linear regression analysis is employed to test the hypothesis with following results: (1) Independence is positively related to auditor's responsibilities in detecting fraud. (2) Competence is positively related to auditor's responsibility to detect fraud. (3) Audit risk is positivele related to auditor's responsibility to detect fraud. (4) Ethical awareness is not related to auditor's responsibility in detecting frau

Analysis of Changes in Pollutant Concentrations Levels Using a Meteorological Normalisation Technique Based on a Machine Learning Algorithm

In this study, a methodological procedure combining a technique of meteorological normalisation, based on a random forest algorithm, with trend analysis and the change points detections in air quality time series is developed to analyse changes in pollutant concentrations levels. Data of air pollutants and meteorological parameters, collected over the period 2013–2019 in a rural area affected by anthropic sources of air pollutants, are used to test the procedure. The results appear to be promising in revealing, in a robust way, changes in pollutant levels not clearly observable in the original data

EURADOS intercomparison exercise on Monte Carlo modelling of a medical linear accelerator

Background. In radiotherapy, Monte Carlo (MC) methods are considered a gold standard to calculate accurate dose distributions, particularly in heterogeneous tissues. EURADOS organized an international comparison with six participants applying different MC models to a real medical linear accelerator and to one homogeneous and four heterogeneous dosimetric phantoms. Aims. The aim of this exercise was to identify, by comparison of different MC models with a complete experimental dataset, critical aspects useful for MC users to build and calibrate a simulation and perform a dosimetric analysis. Results. Results show on average a good agreement between simulated and experimental data. However, some significant differences have been observed especially in presence of heterogeneities. Moreover, the results are critically dependent on the different choices of the initial electron source parameters. Conclusions. This intercomparison allowed the participants to identify some critical issues in MC modelling of a medical linear accelerator. Therefore, the complete experimental dataset assembled for this intercomparison will be available to all the MC users, thus providing them an opportunity to build and calibrate a model for a real medical linear accelerator.