Relationship between mothers\' awareness of eruption time of first permanent molar and its caries in 7-9-year-old children

Introduction: Since the first permanent molar (FPM) as a first permanent tooth erupts between 6-7 years old and has a long period of eruption, it is the most caries prone tooth. One of the problems is inadequate knowledge of parents about the eruption time of the FPM; because these teeth erupt behind the deciduous teeth without a primary successor. In the present study, mothers' knowledge about its eruption time and its effect on health of these teeth was evaluated. Materials& Methods: This cross-sectional study was conducted on 406 schoolchildren (7-9 years old) and their mothers using multi-stage sampling in Babol in 2017. Mothers completed the check list according to the study objectives. Clinical status of FPM was measured using DMFT (Decayed, Missed, Filled Teeth) index. Finally, data were analyzed with SPSS 18 using t-test and chi-square. Significance level was considered as p<0.05. Results: Mothers’ awareness about the eruption time of FPM (p<0.001) was associated with higher ratio of children with sound FPM. Mothers’ education level was the most significant contributing factor to mothers' knowledge about FPM eruption time. Conclusion: Mothers’ education and their knowledge about the FPMs eruption time were the major predictors of FPM caries status

Acid modified carbon coated monolith for methyl orange adsorption

Carbon coated monolith (CCM) was chemically modified by treating with nitric acid. The acid modified carbon coated monolith (ACCM) was then characterized by using various techniques. Two folds increase in acidic sites was observed on ACCM compared to CCM. Surface studies showed mesoporous nature of ACCM. A decrease in ACCM surface area and an increase in pore volume observed after the modification. The ATR-FT-IR studies showed increase in carboxylic groups on ACCM confirming CCM oxidation by nitric acid. The pH studies showed optimum adsorption (88 mg/g) at pH 6 which is very near to pHPZC of ACCM. Contact time studies showed equilibration time in between 4320 and 4560 min for initial MO concentration range 0.05–0.6 g/L. Comparatively 53% higher MO adsorption was observed on ACCM than CCM under similar experimental conditions. Freundlich model applicability confirms multilayer MO adsorption on ACCM surface. Pseudo-second-order kinetics model was fitted best to the experimental data revealing chemical nature of adsorption process. The adsorption process is endothermic and spontaneous in nature. Desorption studies showed optimum MO recovery (73%) when 1 N NaOH was used as an eluent

Carbon coated monolith, a mesoporous material for the removal of methyl orange from aqueous phase: adsorption and desorption studies

The cordierite monolith was successfully modified to carbonaceous material termed as carbon coated monolith (CCM). Surface studies showed about 65% of the total pore volume falls in mesopore range with acidic functionality dominating over the surface. Batch adsorption experiments were carried out to study the applicability of CCM for the removal of methyl orange (MO) from aqueous solution. Different parameters such as effect of MO concentration, contact time, initial pH, regeneration and desorption potential of CCM were studied. Optimum adsorption of MO on CCM was observed at pH 6 (27.2 mg/g). The increase in initial MO concentration from 50 to 500 mg/L leads to increase in adsorption capacity from 15.99 to 88.5 mg/g. The observed equilibration time ranged in between 5000 and 5800 min. Linear and non-linear isotherm studies showed better applicability of Freundlich model. Kinetics studies showed better fitting for pseudo-second-order model. The Weber and Morris model showed multi-linearity indicating two or more steps were involved to describe the adsorption process. Desorption studies showed maximum recovery of MO when alkaline NaOH solution was used as an eluent. The regeneration studies showed decrease in adsorption capacity from 47.93 to 23.76 mg/g after three cycles

Prevalence of Common Methods of Suicide among Iranian Men; a Systematic Review

Background: Suicide is one of the public health problems with a high rate worldwide. Sex is a risk factor for successful suicide, making it the seventh leading cause of death in men in the United States. Based on the increasing suicide rate in Iran, we aimed to investigate the common methods of suicide in Iranian men. Methods: This study is a systematic review with subgroup analysis based on the prevalence of methods of suicide in Iranian men during 2009-2019. Specific keywords based on medical subject headings (MeSH) were searched in Iranian and international databases including PubMed, Scopus, Google Scholar, SID, and MagIran by designing a search strategy. Selected studies were reviewed using the study evaluation tool. For data analysis, STATA software version 14 was used. Also, heterogeneity studies by Q and I2 statics were assessed. Results: In the first phase, 529 studies were extracted, and finally, data were extracted from 19 studies. Because of the heterogeneity of the studies, meta-analysis was not possible and the final results were extracted based on subgroup analysis. Drug abuse was the most common method of suicide and the use of firearms was the least prevalent among Iranian men. Conclusion: Currently, the most common method of suicide in Iranian men is drug abuse. Therefore, it is recommended to design preventive interventions based on gender and take into account commonly available methods

Adsorption of carbon dioxide using activated carbon impregnated with Cu promoted by zinc

In the present study, modified activated carbon (AC) was used in a fixed-bed column for CO2 adsorption of gaseous mixtures. The adsorbents were prepared by impregnation two metals Cu and Zn on the surface of the acid modified AC using a two-stage modification. At the first stage, the samples of AC were pretreated by oxidizing agent (nitric acid) to increase the amount of oxygen surface groups and at the second stage, the acid modified AC were impregnated by two metal salts Cu and Zn on the surface to produce a superior CO2 adsorbent. Metal-loaded acid modified AC was prepared by using different ratios of Cu/Zn ranging from 4 to 20%. The CO2 adsorbed have been measured over the temperature range of (30–50 °C), pressure (100–200 kPa) and CO2 concentrations from 5 to 50%. An increase of 49% CO2 adsorbed was resulted by using modified activated carbon. The breakthrough curves indicated that the breakthrough time increased with increasing the operating pressure, and decreased with increasing the temperature from 30 to 50 °C and CO2 concentration from 5 to 50%. The deactivation model was successfully applied to analyze the breakthrough curves under various operating conditions

Palm oil: features and applications

Palm fruits are the source of two distinct but related vegetable oils, namely palm oil and palm kernel oil. Palm oil has many food and industrial applications. Ever-increasing demands for palm oil have substantially impacted its industry, creating some environmental concerns. Both types of oil are high in saturated fatty acids with potential cardiovascular risks. Several attempts have been made to reduce undesirable health and environmental impacts. However, additional research and development activities are needed to meet the concerns of the medical professionals and environmental activists

Synthesis, characterization and performance evaluation of three-layered photoanodes by introducing a blend of WO3 and Fe2O3 for dye degradation

A three-layered photoanode has been synthesized by the introduction of an additional layer of mixed WO3 and Fe2O3. A total of nine differently-packaged films were prepared by sol-gel method. The fabricated photoanodes were then successfully characterized by X-ray diffractometry (XRD), scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDX). A comparative study was also done to differentiate the films fabricated with WO3, Fe2O3 and their mixture. Compact, columnar tree and shallow patterns were observed on the cross cleavage of the synthesized layers. These distinct patterns were associated with the growth of layers which consequently led to unique surface morphologies. An increase in photocurrent density was observed on the bicomponent film which has been linked to a high degree of surface roughness as well as improved internal porosity. Three-layered photoanodes, modified with an additional bicomponent layer of WO3:Fe2O3 established much higher photocurrent outputs compared to that of nanostructured WO3 or Fe2O3, regardless of the bicomponent layer arrangement. However, with the bicomponent layer on top and middle, the measured photocurrent soared more than three times as much compared to a slight increase observed when the bicomponent was placed on the bottom

Removal of Ni (II) from aqueous solution by an electric arc furnace slag using artificial neural network approach

An artificial neural network (ANN) was built to model the adsorption of nickel on electric arc furnace slag (EAFS). The effect of operating parameters such as pH, the initial metal ion concentration, particle size, and adsorbent dosage were investigated to optimize the sorption process. The operating variables were used as the input for a neural network, which predicted the nickel (II) ion uptake at any time point as the output. The adsorbent was characterized by SEM and BET measurements. From the experimental results the adsorption capacity of 45% was obtained at pH of 8, also as when the adsorbent dosage increases from 0.1 to 1 g/l there is an increase in the percentage removal of Ni(II) ion from 25% to 37% respectively. Further more from the particle size analysis result, it revealed that as the particle size increases from 0.5µm to 3mm the percentage removal of Ni(II) ion decrease from 52% to 33%. Finally by increasing the initial concentration of Ni(II) ion from 50 to 1000 mg L-1, the adsorption capacity also increase from 24% to 43%. The ANN models present high correlation coefficient (R²=1) was found to perform excellently in predicting the adsorption behaviour of nickel in aqueous solutions onto EAFS