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Presents a semiconductor waveguide absorption modulator utilizing a heterostructure field-effect transistor structure. Device extinction ratio; Measurement of transistor transconductance of the materials; Integration of an identical structure in optoelectronic devices.

Demonstrates a field-effect transistor detector with a triple-strained indium gallium arsenide quantum well absorbing region. Characteristics of the detector; Achievement of quantum efficiency at a resonant wavelength; Operation of the transistor detector in the field-effect transistor.

Examines the operation of a single quantum well heterojunction field-effect photodetector. Presentation of responsivity on gate-length device; Basis of the photodetector design; Significance of the third terminal for weighted photodetectors in neutral networks.

Demonstrates the growth of high quality epilayers with doped profiles for the fabrication of laser diodes by solid source molecular beam epitaxy. Display of low threshold current densities in area lasers; Growth of lasers with carbon doped cladding layers; Reliability of carbon-doped lasers.

Background: Polymorphisms of NAT-2 acetylation contribute to drug toxicity, efficacy and cancer risk. Predominance of slow acetylation (SA) phenotype in ethnically distinct populations may have clinical implications for drug selection and cancer risk. The purpose of this study was to determine the genetic basis of SA phenotype predominance in Minnesota Hmong.Methods: Urine and DNA were obtained for phenotype and genotype analysis from unrelated healthy Hmong 18 and 65 years of age. Urinary molar ratios (MR) of caffeine metabolites (AFMU/1X) identified rapid acetylators (RA) phenotypes with a MR >= 0.6 and SA with MR < 0.6. Direct sequencing of the NAT-2 coding-region followed by cloning techniques for ambiguous genotypes identified individuals homozygous or heterozygous with a *4 and *13 allele as RA and variants as SA by genotype.Results: From 61 subjects (30±11 years, 27 male), analysis of 51 urine-DNA pairs identified 46 (90.2%) SA and 5 (9.8%) RA by phenotype. In contrast, genotypic analysis identified 5 (9.8%) SA and 46 (90.2%) RA. An 84% discordance between phenotype and genotype was observed. Direct sequencing did not reveal novel NAT-2 polymorphisms.Conclusions: Genotypic analysis appears to demonstrate considerable discordance with the phenotype in Hmong. Genotyping alone, without a metabolic probe, would not have accurately predicted acetylation phenotype.Clinical Pharmacology & Therapeutics (2005) 79, P72–P72; doi: 10.1016/j.clpt.2005.12.261 [ABSTRACT FROM AUTHOR]

The yearly nutrient supply from land and atmosphere to the study area in SW Kattegat is 10 900 tons of N and 365 tons of P. This is only few percent of the supply from adjacent marine areas, as the yearly transport through the study area is 218000 tons of N and 18250 tons ofP. Yearly nent of the year) resuspension. Resuspension frequency in deep water is less than 1 percent of the year. Resuspension rates, as averages for the study area, are 10-17 times higher than net deposition rates. Because of resuspension, shallow-water sediments are coarse lag deposits with small amounts of organic matter (1.1 percent) and nutrients (0.04 percent N and 0.02 percent P). Deepwater sediments, in contrast, are fine grained with high levels of organic matter (11.7 percent) and nutrients (0.43 percent N and 0.15 percent P). Laboratory studies showed that resuspension changes the diffusive sedimentwater fluxes of nutrients, oxygen consumption, and penetration into the sediment. Fluxes of dissolved reactive phosphate from sediment towater after resuspension were negative in organic-rich sediments (13.2 percent organic matter) with low porosity (56) and close to zero in coarse sediments with a low organic matter content (2.3 percent) and high porosity (73). Fluxes of inorganic N after resuspension were reduced to 70 percent and 0--20 percent in relation to the rates before resuspension, respectively. [ABSTRACT FROM AUTHOR]