Direct observation of shot noise in linewidth broadening of DBR lasers

The relative intensity noise in DBR lasers has been measured as a function of the tuning current. Excellent correlation was found with the expected linewidth broadening, thus identifying shot noise in the passive regions to be the dominant mechanism. The noise spectrum peaks at around 300 MHz.<>     

How can health service users contribute to the NHS research and development programme?

The National Childbirth Trust, along with other groups of health service users, is working with health professionals and researchers in planning clinical trials, setting priorities for research, systematically reviewing research reports, and getting research findings into practice. User groups may bridge the gap between the public and researchers by explaining research issues to a wide audience, presenting the needs and views of health service users to the research community, and suggesting how members of the public may be approached for their views directly. Service users recognise their need for training and support, and they call for development and evaluation of this work.     

Identification of fatty acid ethyl esters as products of rabbit myocardial ethanol metabolism

To characterize metabolic factors potentially associated with alcohol-induced heart disease, myocardial ethanol intermediary metabolism was studied in isolated, perfused rabbit hearts and whole heart homogenates. Results showed that intact rabbit hearts and homogenates of rabbit left ventricle incorporate carbon-14-labeled ethanol at 20 and 59 nmol/g/h, respectively, into a neutral lipid species that co-migrates with triacylglycerides in standard chromatographic solvent systems. After isolation and purification by thin layer chromatography in an apolar solvent system, the labeled species were identified by gas chromatographic-mass spectral analysis to be a family of fatty acid ethyl esters. Heat inactivation of incorporation and the kinetics of formation of products suggest that the process is enzymatic. Gas chromatography identified the fatty acid components as predominantly unsaturated moieties, especially oleic, linoleic, and arachidonic acids. These results provide insight into potential biochemical mechanisms contributing to the triacylglyceride accumulation, decreased beta oxidation of fatty acids, and other lipid abnormalities typical of effects of ethanol on the heart.     

Induction of nephrotoxic nephritis with purified antibody: preparation, properties and assay of antibody

The effects of Vinca alkaloids on the vas deferens have been examined after in vitro and in vivo administration. In the organ bath, vinblastine (1 X 10-4M for 4 hr) caused an increase in sensitivity to noradrenaline and biochemical, histochemical and ulstrastructural signs of noradrenaline depletion from the nerves supplying the outer longitudinal muscle layer. After intravenous injection of Vinca alkaloids the nerve fibres seemed less affected. It is concluded that the apparent resistance to the drugs in vivo is largely due to low tissue perfusion.