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Peter K Mueller

Publications and source records attributed to Peter K Mueller.

4 recordsLinked to original sources

Analysis of a summertime PM2.5 and haze episode in the mid-Atlantic region.

Observations of the mass and chemical composition of particles less than 2.5 microm in aerodynamic diameter (PM2.5), light extinction, and meteorology in the urban Baltimore-Washington corridor during July 1999 and July 2000 are presented and analyzed to study summertime haze formation in the mid-Atlantic region. The mass fraction of ammoniated sulfate (SO4(2-)) and carbonaceous material in PM2.5 were each approximately 50% for cleaner air (PM2.5< 10 microg/m3) but changed to approximately 60% and approximately 20%, respectively, for more polluted air (PM2.5>30 microg/m3). This signifies the role of SO4(2-) in haze formation. Comparisons of data from this study with the Interagency Monitoring of Protected Visual Environments network suggest that SO4(2-) is more regional than carbonaceous material and originates in part from upwind source regions. The light extinction coefficient is well correlated to PM2.5 mass plus water associated with inorganic salt, leading to a mass extinction efficiency of 7.6 +/- 1.7 m2/g for hydrated aerosol. The most serious haze episode occurring between July 15 and 19, 1999, was characterized by westerly transport and recirculation slowing removal of pollutants. At the peak of this episode, 1-hr PM2.5 concentration reached approximately 45 microg/m3, visual range dropped to approximately 5 km, and aerosol water likely contributed to approximately 40% of the light extinction coefficient.

Air Movements↗

Protein synthesis of eucaryotic cells could be decreased by antisense-DNA of the multi KH domain protein vigilin.

Vigilin, a member of the KH protein family, is exceptional among these proteins as it contains 14 KH domains in consecutive order. Vigilin is present in the nucleus and the cytoplasm of all eucaryotic cells studied so far and has apparently high affinity to tRNA and mRNA. There is circumstantial evidence that vigilin expression parallels high translational activity as demonstrated for pancreatic cells in vitro and in vivo as well as for carcinoma cell lines. On a molecular level we have recently demonstrated that vigilin promotes in vitro the export of tRNA from the nucleus to the translational machinery in the cytoplasm and may hence function as an intercompartimental conveyor. In the present study we show that exposure to a vigilin antisense oligo DNA (VAOD) expectedly resulted in a decrease of vigilin-expression, and was concomitant to lower amylase- and trypsin synthesis in freshly isolated pancreatic cells. In addition, carcinoma cells reacted with an increased mortality under exposure to VAOD giving further support for the notion that vigilin participates in cellular life-sustaining processes such as protein translation.

Animals↗