A study on the impact of fire crackers on airborne microflora during diwali

Diwali is celebrated widely in Asian countries, with a custom of firing crackers. Crackers pollute the environment with noise, particulate matter and chemicals. There are reports on the variation of particulates during firing crackers but none on airborne microbes. The present study was conducted to know the impact of fire crackers on airborne microflora. The air samples were collected 3 days prior to Diwali, on Diwali and 3 days after Diwali during the year 2017 at 15 different areas in Chennai, India. Andersen N-6 viable particle air sampler was exposed with petridishes containing nutrient agar and potato dextrose agar for the isolation of bacteria and fungi respectively. An average of 1,904 ± 2.5 CFU/m3 of bacteria recorded prior Diwali was reduced by 53.23% on Diwali and increased by 27.37% after Diwali. This reduction on Diwali is attributed to the exposure of bacteria to chemicals emitted by the crackers. For fungi, an average of 235.57 ± 1.67 CFU/m3 was recorded prior Diwali, with an increase of 78.5% on Diwali. The increase in fungal count might be due to the release of spores by ground crackers. The study shows that bacteria are susceptible to the chemicals emitted by fire crackers when compared with fungi.

Surface active gold nanoparticles biosynthesis by new approach for bionanocatalytic activity

In the present day, nanotechnology is one of the most promising leading scientific and potentials areas in modern key technology development toward to the humankind. The synthesis of noble metal nanoparticles (NPs) is an expanding research area due to the possible applications for the development of bio-medical applications. Eco-friendly approach for the biosynthesis of gold nanoparticles (AuNPs) using the aqueous extract from Ruellia tuberosa and Phyllanthus acidus (leaf and twig) for the first time. Surface active AuNPs were characterized by UV-Vis spectroscopy, FTIR (Fourier transform infrared) spectroscopy, DSC (differential scanning colorimetry), DLS (dynamic light scattering) and environmental SEM (scanning electron microscope) analysis at room temperature (RT). Enhanced surface plasmon resonance (SPR) absorbance UV visible optical spectra were detected in the range of 552, 548, 558 and 536 nm. SEM and DLS (transmission mode) analysis confirmed the morphology of the nanoparticles to be spherical with the average size in the range of 88.37, 94.31, 82.23 and 81.36 nm. Further they have enhanced the enzyme activity on α-amylase, cellulase, and xylanase. The results suggest that the phyto-fabricated AuNPs from R. tuberosa and P. acidus is simple, less expensive, eco-friendly, green synthesis and also can be exploited for the potential future industrial and bio-medical applications.

A comparative study of the efficacy of four different bristle designs of tooth brushes in plaque removal

BACKGROUND

The aim of the study was to compare the efficacy of four most commonly used bristle designs of toothbrushes in plaque removal.

MATERIALS AND METHODS

The study was a randomized 4 cell, examiner blind cross-over design assessing the plaque removal efficacy of all four brushes on a single occasion. Sixteen subjects aged 14-15 years participated in the study. On day 1 of each test period, the subjects were rendered plaque free and were asked to suspend oral hygiene practices for 24 hours. On day 2, the subjects were scored for plaque prior to brushing using the Turesky-Gilmore modification of Quigley-Hein plaque index. The subjects then brushed with the allocated toothbrush for 2 minutes and the post-brushing plaque scores were assessed. A wash-out period of 4 days was allowed between the test periods.

RESULTS

All the brushes showed a significant reduction in the post-brushing plaque scores ( p < 0.001). The mean reduction in the plaque scores for all the brushes was around 53%. The percentage plaque reduction was greater in the anterior surface than the posterior surface (59.6 +/- 7.45% vs. 49.83 +/- 4.35%). The percentage plaque reductions in the upper, lower, buccal and lingual surfaces were similar. No significant difference in the reduction of plaque scores between the four brushes was seen.

CONCLUSION

The data derived from the study supports the contention of many researchers that there is no single superior design of manual toothbrush. Though minor and some site differences in favor of the brushes were seen, they were not statistically significant.