Taguchi based fuzzy logic optimization of multiple quality characteristics of cobalt disulfide nanostructures

Cobalt sulfide nanostructures, with a formula of CoxSy, have recently received considerable attention due to their unique catalytic, electric, magnetic, optical, and mechanical properties. In this study, cobalt disulfide (CoS2) nanoparticles have been synthesized by the solvothermal method using cobalt chloride and sodium thiosulfate as the precursors. The Taguchi method has been implemented to investigate and optimize the affecting parameters involved in minimizing the band-gap energy. Then, the predictions used to model the anticipated results with fuzzy logic. It has been found that the reaction temperature and the precursor ratio are the most effective parameters when attempting to minimize the band-gap energy

Mothers view about oral health status, oral hygiene behaviors, and dental services utilization of their children with hearing impairment attending special schools

Aim: Parents are the principal decision-makers regarding their child's health. Awareness of mothers� view about their children's health, particularly with special health care needs (SHCN) (include hearing impaired children), is essential for health care providers. Therefore, the present study aimed to assess the mothers view about oral health status, oral hygiene practices, and dental services utilization of their children with hearing impairment attending special schools. Methods: A cross-sectional study was conducted between May and September 2020 among mothers of students with hearing impairment attending special schools. Also, the telephone structured interview was used to gathering mothers view. Results: 57.4 of the mothers rated their children's oral health status as excellent or good, 27.9 as moderate, and 14.7 as poor. About half of the mothers (49.2) stated that their children used toothbrushes once daily, and 15 use dental floss. Also, 54 of the children visited the dentist before this survey's conduct. Conclusion: The findings of the present study suggest that children with hearing impairment can also have good oral health status and behaviors. These results may be attributed to the fact that the study sample was taken from two special schools. Also, only the mothers� perception assessment of students� oral health status was done. Further studies are required to increase the strength of evidence. © 2021 Special Care Dentistry Association and Wiley Periodicals LL

Drug resistance pattern of Mycobacterium tuberculosis in the province with highest incidence of tuberculosis in Iran

Objective/background Incidence of tuberculosis (TB) in Golestan Province is consistently higher than other provinces of Iran. This study aimed to determine the rate of drug resistance to first-line antibiotics in Mycobacterium tuberculosis (MTB) isolates recovered from new cases in this province. Methods The sputum and broncho-alveolar lavage samples from 3828 patients who were suspected for active TB were collected from March 2015 to July 2015. All specimens were subjected to smear microscopy and culture. Drug susceptibility testing to rifampicin, isoniazid, ethambutol, and streptomycin was performed on Löwenstein–Jensen medium using proportion method. Results Of 3828 clinical specimens, 40 were culture-positive for MTB. The mean age of patients was 48.6 ± 17.5 years and 23 (57%) patients were male. Thirty-eight patients were native Iranians while two (5%) were immigrant patients from Turkmenistan and Afghanistan. A set of 34 (85%) isolates were pan-susceptible, six (15%) were resistant to at least one drug, and one isolate (2.5%) was multidrug resistant. Conclusions The rate of drug resistance in this study area point to the necessity for further enforcement of TB treatment and disease control management. Future studies are recommended for assessments of drug resistance pattern of MTB isolates in Golestan Province. © 201

Multi-objective optimization of reaction parameters and kinetic studies of cobalt disulfide nanoparticles

In this study, cobalt disulfide (CoS2) nanoparticles have been successfully synthesized through a simple and facile solvothermal method. The experiments were carried out based on the thermodynamic calculations using FactSage software. The black nano-sized CoS2 powder has been produced in an autoclave reactor. The reaction parameters, such as the ratio of primary salts, effect of solvents, temperature and surfactant were optimized to obtain fine and uniform nanoparticles. The band gap energy of the samples was measured with butler relations. The results proved the production of highly pure CoS2 nanoparticles with a semi-spherical morpholog