PubMed Health⌕ Search

Biomedical subjects

M Witcomb

Publications and source records attributed to M Witcomb.

4 recordsLinked to original sources
PubMed2006

Fabrication of a nanostructured gold-polymer composite material.

A facile synthesis route is described for the preparation of a poly-(o-aminophenol)-gold nanoparticle composite material by polymerization of o-aminophenol (AP) monomer using HAuCl(4) as the oxidant. The synthesis was carried out in a methanol medium so that it could serve a dual solvent role, a solvent for both the AP and the water solution of HAuCl(4). It was found that oxidative polymerization of AP leads to the formation of poly-AP with a diameter of 50+/-10nm, while the reduction of AuCl(4) (-) results in the formation of gold nanoparticles ( approximately 2nm). The gold nanoparticles were uniformly dispersed and highly stabilized throughout the macromolecular chain that formed a uniform metal-polymer composite material. The resultant composite material was characterized by means of different techniques, such as UV-vis, IR and Raman spectroscopy, which offered the information about the chemical structure of polymer, whereas electron microscopy images provided information regarding the morphology of the composite material and the distribution of the metal particles in the composite material.

Aminophenols↗
PubMed2003

Do junior doctors take sick leave?

Nosocomial infections place a heavy burden on overstretched health services. An audit of junior doctors' sick leave behaviour was undertaken in 1993 and again in 2001. The object was to ascertain the level of common infectious illness and to investigate whether junior doctors were remaining at work inappropriately. The doctors were asked if any factors had influenced their decision to take sick leave or not. Between the two audits several initiatives have been introduced to improve the working conditions of junior doctors, including the New Deal to reduce hours of work. Eighty one junior doctors in a large teaching hospital participated in 1993 and 110 in 2001. The number reporting an infectious illness in the previous six months was similar (61.7% in 1993, 68.2% in 2001). There had been a significant increase in the percentage of infectious illness episodes for which the doctors took sick leave (15.1% in 1993, 36.8% in 2001, p < 0.001). The most common reason for taking less sick leave than was felt necessary was concern about colleagues having to do extra work (72% in 1993, 68% in 2001). Consultant pressure was cited by 26% (1993) and 20% (2001). Use of the staff occupational health unit was minimal, with none of the ill doctors contacting the department in 1993 and only three in 2001. Overall, despite the reduction in the number of infectious doctors not taking sick leave, the majority remained at work. Fundamental changes are needed if potentially infected doctors are not to present a risk of iatrogenic infection.

Attitude of Health Personnel↗
PubMed1978

Epidemic listeriosis. Report of 14 cases detected in 9 months.

During the period August 1977 to April 1978, 14 Black patients in Johannesburg area had systemic infections caused by Listeria monocytogenes. Nine of these patients were neonates who presented with septicaemia (5 cases) or septicaemia and meningitis (4 cases) and 5 were adults, all of whom had meningitis. The mortality rate was 43% (6/14), with 4 neonatal and 2 adult deaths. All isolates of L. monocytogenes were type 4b. Only sporadic cases of human listeriosis have previously been reported in South Africa, and the cases reported here constitute the first epidemic in this country.

Adult↗