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Abstract: The highly efficient red phosphors (Ca1−x Sr x )(S1−y Se y ):Eu2+,M3+ (M=Sc and Y) were prepared, starting from CaCO3, SrCO3, Eu2O3, Sc2O3, Y2O3, S, and SeO2 with a flux, by a conventional solid-state reaction. The optimized red phosphors converted 11.8% (Sc3+) and 11.7% (Y3+) of the absorbed blue light into luminescence. These quantum values are much higher than Q =3.0% of CaS:Eu2+. For the fabrication of light-emitting diodes (LEDs), the prepared phosphors were coated with MgO from non-aqueous solution to overcome their weakness against moisture. White LEDs were fabricated by pasting the prepared red phosphors and the yellow YAG:Ce3+ phosphor on an InGaN blue chip (λ ems =446.5nm). The incorporation of the red phosphor to the YAG:Ce3+ phosphor resulted in an improved color rendering index (Ra) from 70 to 80. [Copyright &y& Elsevier]

The present study examined the effects of chorionicity of twins on variations of height, weight, and body mass index (BMI) during childhood in the classical twin design. Mothers of 81 pairs of monochorionic monozygotic (MCMZ), 47 pairs of dichorionic monozygotic (DCMZ), and 457 pairs of dizygotic (DZ) twins drawn from the South Korean Twin Registry reported their children's height and weight. Twins' age ranged from 1.9 to 8.7 yrs, with a mean of 4.0 yrs and SD of 1.7 yrs. We computed maximum likelihood twin correlations and performed model-fitting analyses. In correlational and model-fitting analyses, we treated age and sex as covariates to control their main effects. Maximum likelihood MCMZ, DCMZ, and DZ twin correlations were, respectively, .96, .92, and .74, for height, .88, .91, and .57 for weight, and .93, .92, and .61 for BMI. The pattern of these twin correlations suggested very modest chorion effects on body measures. Model-fitting analyses confirmed the observations from twin correlations. Whereas genetic and shared environmental influences were significant for all three body measures, chorion effects attained statistical significance only for height (4%), and those for weight and BMI were zero. These findings indicate that genetic and environmental estimates for height, weight, and BMI during childhood are biased little by the chorion type of MZ twins, supporting the validity of the equal prenatal environment assumption in the classical twin design. [ABSTRACT FROM AUTHOR]

A total of 2,026 leprosy patients of the National Sorokdo Hospital was examined their intestinal parasites by cellophane thick smear method in January 1983. The egg positive cases of Taenia spp. were treated with bithionol and the segments of Taenia were collected for species identification. The results were as follows: 1. Total egg positive rate of any kind helminth was 78.2 % and cumulative total was 85.2 %. The egg positive rate for each helminth was as follow; Taenia spp. 3.4 %, Ascaris lumbricoides 4.5 %, Trichuris trichiura 72.l %, Clonorchis sinensis 2.8 % and other 0.05 %. 2. A total of 66 Taenia egg positive cases was treated; out of them proglottids of Taenia were collected from 26 cases. All of the collected worms were identified as T. saginata. The results revealed significantly high egg positive rate of T. trichiura. However, A. lumbricoides was found to be controlled considerably by repeated chemotherapy during past 3 years. If chemotherapeutic agent is replaced with oxantel-pyrantel tablet, better result is expected. No clue was found for prevalence of T. solium from both human and the pig in the island.