The impact of magnification on undergraduate dental students' performance during cavity preparations: A systematic review.

PURPOSE/OBJECTIVES: Loupe magnification is a commonly utilized tool within dental education due to its proposed benefits of improving working posture, visual acuity, and procedural quality. Although procedural quality has been researched at the graduate level, literature encompassing the undergraduate level remains scarce. Therefore, this systematic review aims to critically assess the available literature to ascertain the effects of loupe magnification on the performance of undergraduate dental students' cavity preparations. MATERIALS AND METHODS: A systematic search was conducted across electronic databases, including PubMed, MEDLINE via Ovid, The Cochrane Library for Cochrane Reviews, and Scopus, to identify relevant studies published from inception to February 15, 2023. We included English language studies that evaluated the effect of loupe magnification on the performance of undergraduate dental students in cavity preparations. RESULTS: In total, six studies fulfilled the inclusion criteria. The outcomes assessed encompassed tooth preparation accuracy. Of these six articles, one was conducted on endodontic access cavity preparations, four on restorative cavity preparations, and one on nonstandard cavity preparation designs performed on acrylic blocs. Four articles determined that loupes positively impacted undergraduate students' performance in cavity preparations, while two articles established no significant difference in performance between loupes and naked-eye cavity preparations. CONCLUSION: This systematic review suggests that loupe magnification positively impacts undergraduate dental students' performance in cavity preparations. However, the heterogeneity of the studies and the variations in methodologies limit the ability to draw definitive conclusions.

Removal of copper ions from wastewater by adsorption/electrosorption on modified activated carbon cloths.

Adsorption and electrosorption of copper ions (Cu(2+)) from wastewater were investigated with variously modified activated carbon fiber (ACF) cloth electrodes. Commercial polyacrylonitrile-based ACF cloths were modified by nitric acid or impregnated with chitosan solution. The surface characteristics of ACFs before and after modification were evaluated by nitrogen adsorption-desorption isotherms, zeta potential, Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS) and cyclic voltammetry. Adsorption and electrosorption capacities of Cu(2+) on ACF cloths without and with a bias potential were measured, respectively, and the electrosorption isotherms were also investigated. The initial pH of the copper ion solution was adjusted to 4.0. Experimental results showed that electrosorption effectively increases adsorption capacity. The adsorption/electrosorption isotherms of Cu(2+) on ACF cloths were in good agreement with Langmuir and Freundlich equations. The equilibrium adsorption capacity at 0.3 V was 0.389 mmol/g, which is two times higher than that at open circuit. The maximum electrosorption capacity of Cu(2+) on chitosan impregnated ACF cloths was 0.854 mmol/g, which is about 2.2 times higher than that on the pristine cloths.

Effect of surface acidic oxides of activated carbon on adsorption of ammonia.

The influence of surface acidity of activated carbon (AC) was experimentally studied on adsorption of ammonia (NH(3)). Coconut shell-based AC was modified by various acids at different concentrations. There were five different acids employed to modified AC, which included nitric acid, sulfuric acid, hydrochloric acid, phosphoric acid, and acetic acid. Acidic functional groups on the surface of ACs were determined by a Fourier transform infrared spectrograph (FTIR) and by the Boehm titration method. Specific surface area and pore volume of the ACs were measured by a nitrogen adsorption apparatus. Adsorption amounts of NH(3) onto the ACs were measured by a dynamic adsorption system at room temperature according to the principle of the ASTM standard test method. The concentration of NH(3) in the effluent stream was monitored by a gas-detecting tube technique. Experimental results showed that adsorption amounts of NH(3) on the modified ACs were all enhanced. The ammonia adsorption amounts on various activated carbons modified by different acids are in the following order: nitric acid>sulfuric acid>acetic acid approximately phosphoric acid>hydrochloric acid. It is worth to note that the breakthrough capacity of NH(3) is linearly proportional to the amount of acidic functional groups of the ACs.

Effect of moisture on H(2)S adsorption by copper impregnated activated carbon.

The aim of this study is to investigate the effect of moisture on adsorption efficiency of hydrogen sulfide (H(2)S) by impregnated activated carbon (IAC). Copper(II) nitrate was used as an impregnant. Two humidification conditions of IAC, pre-moistened and gas stream containing moisture, were studied. The experimental results revealed that the copper species onto the IAC was suggested to be Cu(OH)(2) that deposited on activated carbon during the impregnation process. The adsorption mechanism of H(2)S by copper impregnated IAC was proposed, involving physic-sorption and chemical reactions. Moreover, the H(2)S breakthrough capacity decreased with increasing the relative humidity of gas stream. The causes were attributed to three points as follow: the competition adsorption occurred between moisture and H(2)S; the copper(II) species reduced to copper(I) species leading to IAC deactivation; and the rate of chemical reaction restrained by moisture.

SpliceInfo: an information repository for mRNA alternative splicing in human genome.

We have developed an information repository named SpliceInfo to collect the occurrences of the four major alternative-splicing (AS) modes in human genome; these include exon skipping, 5'-alternative splicing, 3'-alternative splicing and intron retention. The dataset is derived by comparing the nucleotide and protein sequences available for a given gene for evidence of AS. Additional features such as the tissue specificity of the mRNA, the protein domain contained by exons, the GC-ratio of exons, the repeats contained within the exons, and the Gene Ontology are annotated computationally for each exonic region that is alternatively spliced. Motivated by a previous investigation of AS-related motifs such as exonic splicing enhancer and exonic splicing silencer, this resource also provides a means of identifying motifs candidates and this should help to identify potential regulatory mechanisms within a particular exonic sequence set and its two flanking intronic sequence sets. This is carried out using motif discovery tools to identify motif candidates related to alternative splicing regulation and together with a secondary structure prediction tool, will help in the identification of the structural properties of such regulatory motifs. The integrated resource is now available on http://SpliceInfo.mbc.NCTU.edu.tw/.