Controllable gold nanoparticle deposition on carbon nanotubes and their application in immunosensing

A CNT–AuNPs hybrid nanocomposite platform was prepared from nanodisperse AuNPs in N-[3-(trimethoxysilyl)propyl]ethylenediamine (EDAS) sol–gel matrices with purified MWCNT.

The effect of tinted spectacle lenses on contrast sensitivity and colour vision

Aim: Spectacle wearers often prefer tintedlenses to clear or non-tinted lenses for their protection against harmful radiation, improved cos-mesis, enhancement of visual performance and effects on colour vision. Among the available tinted lenses on the market blue, brown and grey tinted spectacle lenses are popular with varying gradesranging from A to D. Due to reduced transmission of light through such lenses, the optical system of the eyes and the environmental vision may be temporarily altered. Colour vision (CV) and con-trast sensitivity (CS) are important aspects of this altered visual world. This study investigated the effect of spectacle lenses of varying grades of tint on CS and CV.Method: The study adopted a pre- and postest research design and a sample of 90 participants were selected from the University of KwaZulu-Natal student population using convenience sam-ling. Each participant was screened for patholgy, dyschromatopsia, severe dry eyes (TBUT<5 seconds), and the presence of any more than low metropia. Thereafter each successful participant was tested for CS and CV with their habitual precription and then tested randomly with a white clear) lens (placebo) and tinted (blue, brown, and grey) spectacle lenses made of CR39 material each having grades A, B and C over their habitual state. Light transmission was 85%, 75%, and 50% for grades A, B, and C respectively. The Functional Acuity Contrast Test (FACT) chart and American Optical Hardy, Rand, and Rittler (AO HRR) were used for the assessment of CS and CV respectively.Results: The data was analysed using the Statistical Package of Social Science (SPSS) version18. Compared to the habitual state, contrast sensitivity was enhanced with all the tinted lensesThe greater enhancement was for low spatial frequencies (LSF) and least for high spatial frequencies (HSF). With all tints Grade C had the least enhancement for very HSF. Many subjects showed no change in CV with any of the lensesused. The grey tint showed greater enhancement of CV as the density increases. Blue and brown tints showed a similar trend with grade B enhancing CV the most while grade C resulted in theleast reduction of CV.Conclusion: Grade A, B, and C of blue, brown and grey tinted spectacle lenses do not alter colour vision significantly but for the selected levels of transmission of the tints used, contrast sensitivity can be improved to some extent. 

Paediatric trauma epidemiology in an urban scenario in India

PURPOSES

To identify the epidemiology of paediatric trauma in an urban scenario of India and compare results with studies from developed countries, and to formulate preventive measures to decrease such traumas.

METHODS

Between January 2004 and 2005 inclusive, 500 paediatric, orthopaedic trauma patients presenting to our hospital were prospectively studied. Information was recorded in a prescribed proforma.

RESULTS

The children's ages ranged from 0 to 16 years; 274 were males. Most fractures occurred in children aged 7 to 12 years and decreased in older children. The ratio of fractures in left versus right upper extremity was 2:1. In children aged 0 to 6 years, the most common injured site was the elbow, whereas in children aged 7 to 16 years it was the distal radius. In descending order, most injuries were sustained at home (47%), in school (21%), due to sports (17%), and due to vehicular accidents (13%).

CONCLUSION

An effective accident prevention programme in developing countries requires changes in lifestyle and environment, and overcoming obstacles such as ignorance, illiteracy, and inadequate resources.