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In this paper we define seasonal and along-shore variations in suspended particle size distributions (PSDs) at two marine bathing beaches in southern California, using a low-angle light scattering instrument (LISST). Empirical Orthogonal Function (EOF) analysis of the LISST data set (n = 55 651) identified three particle size modes that collectively account for > 90% of the variance in the de-meaned PSD data at six sites along the shoreline at Huntington Beach and Newport Beach: a dinoflagellate mode, a large particle mode, and a small particle mode. These three modes exhibit distinct seasonal patterns, and along-shore distributions, reflecting both the sources of particles and environmental factors that trigger their occurrence. Comparison of volume-based PSDs generated from the LISST and from image analysis of optical micrographs indicates that the LISST performs well when measuring the size distribution of particles associated with dinoflagellate blooms. However, LISST measurements on stormwater-impacted samples consistently yield a rising tail at small particle sizes that may be an artifact arising from the non-spherical nature of inorganic particles in terrestrial runoff. The results presented here demonstrate that PSDs measured by light scattering instruments such as the LISST represent a new data resource for assessing water quality, and managing human health risk, at marine bathing beaches.

Santonin-kainic acid complex was evaluated as a chemotherapeutic of the mass treatment of the Ascaris lumbricoides infection in Korea. The results could be summarized as follows: 1) The negative conversion rate was 82.9% in average in 4 treated groups. Some variations of negative conversion rate among the treated groups were noticed. 2) The egg reduciton rate was 97.7% in average and the results were rather uniform among the three evaluated groups. 3) By the analysis of egg reduction, it seems that the lightly infected cases whose E.P.G. were under 5,000 were resistant to treatment with the less reduced egg output. 4) After the treatment with this complex, the number of egg discharged cases were reduced to 1.84% and the average number of discharge eggs per incompletely treated or untreated cases were reduced to 12.5% compared with the level of before-treatment egg output. 5) The successive observations of the pattern of worm expulsion after drug intake was made. The worms were mostly expelled in the stool within 3 days, and 58.9% of total expelled worms were collected within 24-hour stool. 6) The minimum length of the immature worms expelled was 7.6cm. Among the 659 Ascaris collected in the first-day stool from 91 rural people, 8.5% were in the range of 7.6-12.2 cm-long, immature worms. The sex ratio, male: female= 0.69: 1.

The authors examined 3,169 fecal specimens from inhabitants of seven localities such as City, Eups and Myons in Cheju Do on July 1970 with cellophane thick smear technique. The results were analysed and summarized as follows: 1) The overall egg positive rate of helminths was 82.2% and it was attributed to high rates of soil-transmitted helminths as in case of other parts in Korea. 2) The infection rates of each species were; A. lumbricoides 44.3%, T. trichiurus 65.6%, hookworm 1.5%, T. orientalis 0.8%, C. sinensis 0.2%, P. westermani 0.4%, M. yokogawai 0.9%, Taenia sp. 12.7% and H. nana 1.4%. 3) The infection rates of soil-transmitted helminths were relatively lower than those of mainland Korea especially in case of hookworm and T. orientalis. The proportion of unfertilized ova passers among the Ascaris infected case was 22.1%. 4) The ova of heterophyids, most probably Metagonimus yokogawai were detected in lower percentage but discovered throughout the localities surveyed and in all age groups. It is certainly presumed that Metagonimus infection is autochthonous. 5) The most interesting results were obtained in Taenia sp. infection and the higher rates were shown in rural area than in urbanized areas. The positive rates were within 5% in childhood and adolescence but abruptly increased up to 36.4 % in adults.