Study on the effect of wet scrubbing technique on emissions in a dual fuel engine operating with diesel and hydrogen.

Reducing emissions from internal combustion (IC) engines is a crucial goal, encompassing nitrogen oxide (NO), hydrocarbon (HC), carbon monoxide (CO), and smoke. To enhance both performance and emissions, contemporary IC engines have turned to alternative gases such as hydrogen (H2) and exhaust after-treatment systems. A promising method to effectively decrease exhaust emissions entails the application of the scrubber technique as an exhaust gas after-treatment. This study's objective is to explore two avenues for curtailing exhaust emissions. The first involves substituting traditional fuels in IC engines with hydrogen gas (H2) at a flow rate of 6 LPM. The second entails integrating a liquid chemical solution into the scrubber technique. Notably, the utilization of KMnO4 solutions exhibits an appreciable reduction in NO and CO emissions compared to solutions containing NaOH. The experimental process included two aspects: investigating hydrogen fuel (H2) as an alternative fuel for IC engines and incorporating a scrubber technique using both KMnO4 and NaOH solutions. These experiments were conducted using a single-cylinder engine with a power output of 5.2 kW, cooled by water. The engine underwent tests under various load conditions, spanning from minimal to maximal loads. The findings revealed that employing KMnO4 solutions within the scrubber technique led to reductions of 25% and 40% in NO and CO emissions, respectively, in contrast to the utilization of NaOH solutions. Similarly, introduction hydrogen gas also has a significant effect on emission reduction.

Effect of activated chlorhexidine and irritrol with photon-induced-photoacoustic-streaming and EDDY® on the dislocation resistance of biodentine.

Background: Irrigant activation techniques, which are more effective in anatomically complex areas, can be used to maximize irrigant efficacy. Aim: This in vitro study aimed to evaluate the efficacy of different agitation techniques on the dislocation resistance of Biodentine to the root canal dentin. Materials and Methods: Seventy single-rooted teeth divided into seven experimental groups (n = 10); Group I-Irritrol/Photon-induced-photoacoustic-streaming (PIPS), Group II-Irritrol/EDDY®, Group III- Irritrol/Syringe-needle-irrigation (SNI), Group IV-Chlorhexidine-gluconate (CHX)/PIPS, Group V-CHX/EDDY®, Group VI-CHX/SNI, Group VII-Saline. The midroot dentin slice was obtained from each tooth, and Biodentine was condensed with hand pluggers into the root canal lumen. The push-out bond strength values were measured using a universal testing machine. Each sample was categorized into one of the three failure modes: adhesive/cohesive/mixed. Scanning-Electron-Microscopy (SEM) was used to conduct the analyses, and the composition of Biodentine was analyzed using Energy-Dispersive Spectroscopy. The One-way ANOVA, post-hoc Tukey's test, and the Chi-square test were used for statistical analysis. Results: The push-out bond strength values of Biodentine showed that Group VII-Saline had a statistically significant difference (P = 0.002), however, the differences between the other groups were not statistically significant (P = 0.922). The percentages of the failure modes of the samples showed that there was a higher rate of mixed failure except for Group VII-Saline. SEM examination showed that Group VII-Saline had no open dentinal tubules, whereas the other groups, particularly the Irritrol groups, had open dentinal tubule areas. Conclusions: Within the scope of the study, using Irritrol or CHX as the final irrigation in the root canal treatment did not result in differences in the dislocation resistance of Biodentine to root canal dentin when PIPS and EDDY® were used.

Avaliação da desinfecção dos cones de guta percha utilizando diferentes produtos químicos: revisão de literatura / Evaluation of the disinfection of guta percha cones using different chemicals: literature review

Introdução: Os cones de guta percha são utilizados para obturação de canais radiculares, entretanto a desinfecção desses cones deve ser realizada previamente à obturação, evitando uma contaminação, uma vez que com o manuseio diário na clínica, pode ocorrer a proliferação de microrganismos. Objetivo: Relatar através de uma revisão de literatura a importância da desinfecção de cones de guta percha previamente á obturação dos canais radiculares, com diferentes soluções desinfetantes utilizadas na odontologia. Metodologia: Foi realizada uma busca em artigos de revisão de literatura nas bases de dados Pubmed, Scielo, Lilacs com diferentes anos de publicação, mas todos com enfoque principal no tema de desinfecção de cones de guta percha com diferentes soluções químicas. Foram utilizados os descritores guta percha, desinfecção, soluções químicas. Conclusão: Medidas de prevenção devem ser empregadas durante o atendimento odontológico, em especial durante a obturação dos canais radiculares, sendo a desinfecção dos cones de guta percha essencial(AU)

Introduction: Gutta percha points are used to fill root canals, however its disinfection must be performed prior to filling, avoiding contamination, since with daily handling in the proliferation of microorganisms can occur. Objective: To report through a literature review the importance of disinfecting gutta percha points prior to root canal filling, with different disinfectant solutions used in dentistry. Methodology: A search for literature review articles was carried out in the Pubmed, Scielo, Lilacs databases with different years of publications, but all with a main focus on the topic of disinfection of gutta-percha points with different chemical solutions. The keywords gutta percha, disinfection, chemical solutions were used. Conclusion: Preventive measures must be used during dental care, especially during root canal filling, with the disinfection of gutta percha points being an essential(AU)

Modeling sources of interlaboratory variability in electrophysiological properties of mammalian neurons.

Patch-clamp electrophysiology is widely used to characterize neuronal electrical phenotypes. However, there are no standard experimental conditions for in vitro whole cell patch-clamp electrophysiology, complicating direct comparisons between data sets. In this study, we sought to understand how basic experimental conditions differ among laboratories and how these differences might impact measurements of electrophysiological parameters. We curated the compositions of external bath solutions (artificial cerebrospinal fluid), internal pipette solutions, and other methodological details such as animal strain and age from 509 published neurophysiology articles studying rodent neurons. We found that very few articles used the exact same experimental solutions as any other, and some solution differences stem from recipe inheritance from advisor to advisee as well as changing trends over the years. Next, we used statistical models to understand how the use of different experimental conditions impacts downstream electrophysiological measurements such as resting potential and action potential width. Although these experimental condition features could explain up to 43% of the study-to-study variance in electrophysiological parameters, the majority of the variability was left unexplained. Our results suggest that there are likely additional experimental factors that contribute to cross-laboratory electrophysiological variability, and identifying and addressing these will be important to future efforts to assemble consensus descriptions of neurophysiological phenotypes for mammalian cell types. NEW & NOTEWORTHY This article describes how using different experimental methods during patch-clamp electrophysiology impacts downstream physiological measurements. We characterized how methodologies and experimental solutions differ across articles. We found that differences in methods can explain some, but not all, of the study-to-study variance in electrophysiological measurements. Explicitly accounting for methodological differences using statistical models can help correct downstream electrophysiological measurements for cross-laboratory methodology differences.

Sci-Sat AM: Brachy - 03: Feasibility study of the determination of absorbed dose to water using a fricke based system.

By measuring the dose to water directly a metrology standard, independent of air kerma, can be developed to make the basis of HDR brachytherapy dosimetry consistent with current dosimetry methods for external radiation beams. The Fricke dosimeter system, a liquid chemical dosimeter, provides a means of measuring the absorbed dose rate to water directly by measuring the radiation-induced change in absorption of the Fricke solution. In an attempt to measure the absorbed dose to water directly for a 192 Ir HDR brachytherapy source a ring shaped Fricke holder was constructed from PMMA, essentially following the work of Austerlitz et al. (Med. Phys. 2008). Benchmark measurements conducted in a 60 Co beam yielded a standard uncertainty in the absorption reading of 0.16 %, comparable with previous results in the literature. Measurements of the standard uncertainty of the control (unirradiated) solution using the holder yielded 0.2 %, indicating good process control and minimal contamination from the holder itself. However, it was found that the holder sealing method (to allow measurements in a water phantom) significantly contaminated the Fricke solution, resulting in an excessive background reading. Irradiations were therefore conducted in air to determine the feasibility of the procedure. Irradiations with a 17 GBq source gave a standard uncertainty of approximately 0.5 %, indicating that the target uncertainty of 1.5% for the measurement of absorbed dose to water using a Fricke-based primary standard is achievable. This would be comparable with calorimeter-based systems currently being developed.