During 19837 a clinical diagnosis of subacute sclerosing panencephalitis (SSPE) was confirmed by the detection of measles virus haemagglutination inhibiting antibody in the cerebrospinal fluid (CSF) in 81 subjects resident in Tamilnadu. The antibody titre (reciprocol of the endpoint dilution) in the CSF ranged from 2 to 32 and in the sera from 8 to 2048. The CSF: serum ratios of titres were 1:41:64 in 80 cases and 1:128 in one case. The median age at onset of SSPE was 10 years and 97% of cases were diagnosed at stage 2 and beyond. Based on the geographic distribution of 72 cases in an estimated population of 84 million, the annual incidence of SSPE was calculated to be 214 per million population, or 43 cases per million children below 20 years. Assuming that only 10% of all cases would have reached the level of laboratory diagnosis, the incidence may be as high as 21 cases per million population.

Thermal and photo-optical properties of azoxybenzene/alkyloxy-azobenzene containing chiral dimesogens are presented. Alkyloxyazobenzene containing dimesogenic materials exhibited two kinds of smectic A phases. Photoirradiation at temperatures exhibiting smectic phases of pure materials in azobenzene linked dimesogens resulted in formation of the isotropic phase, and this was systematically studied at different liquid crystalline temperatures. The efficacy of these compounds as a dopant in the glassy liquid crystalline material was also explored. Increasing concentration to 4 wt%/5 wt% in azobenzene/azoxy-benzene derivatives caused a dramatic red-shift in the wavelength of reflected light by the host cholesteric glassy liquid crystal. Photo-isomerization of these dopants led to a blue-shift of the reflected light, and this effect could be used to tune the light reflectivity of these mixtures over the visible region.

Four halophytes belonging to three dicotyledon families, Acanthaceae, Aizoaceae and Chenopodiaceae, were screened for the presence of fungal endophytes. Thirty-six species of fungi, including some sterile forms, were isolated. Camarosporium species showed some degree of host preference as they were the dominant endophytes of the halophytes of Chenopodiaceae but were absent from the other halophytes. Some genera such as Colletotrichum, Phomopsis, Phyllosticta and Sporormiella were ubiquitous.