Phosphorus is required for numerous cellular compounds and as a result can serve as a useful proxy for total cell biomass in studies of cell elemental composition. Single-cell analysis by synchrotron X-ray fluorescence (SXRF) enables quantitative and qualitative analyses of cell elemental composition with high elemental sensitivity. Element standards are required to convert measured X-ray fluor...

1. Chemical analyses of ecologically diverse species of Drosophila reveal substantial variation among them in their nitrogen and phosphorus contents, determined as a percentage of adult dry mass. Across Drosophila species, the nitrogen content of flies is positively correlated with phosphorus content. 2. For both N and P, the concentration in the flies is correlated with that of their breeding ...

The chemical composition of secondary organic aerosol (SOA) particles, formed by the dark ozonolysis of αpinene, was characterized by a high-resolution time-of-flight aerosol mass spectrometer. The experiments were conducted using a continuous-flow chamber, allowing the particle mass loading and chemical composition to be maintained for several days. The organic portion of the particle mass loa...

A. M. Parsons, L. G. Evans, S. Karunatillake, T. P. McClanahan, J. E. Moersch, S. F. Nowicki, J. S. Schweitzer, R. D. Starr, S. Squyres and G.J. Taylor NASA Goddard Space Flight Center, Code 691, Greenbelt, MD 20771, [email protected], Computer Sciences Corporation, Lanham, MD 20706, Louisiana State University, Baton Rouge, LA 70803, University of Tennessee, Knoxville, TN 37996, Universiti...

The new field of 'stoichiogenomics' integrates evolution, ecology and bioinformatics to reveal surprising patterns of the differential usage of key elements [e.g. nitrogen (N)] in proteins and nucleic acids. Because the canonical amino acids as well as nucleotides differ in element counts, natural selection owing to limited element supplies might bias monomer usage to reduce element costs. For ...

Prokaryotic heterotrophs (hereafter, bacteria) represent a large proportion of global biomass, and therefore bacterial biomass stoichiometry likely exerts control on global phosphorus (P), carbon (C), and nitrogen cycling and primary productivity. In this study we grew recently isolated freshwater heterotrophic bacteria across an ecologically relevant range of resource C:P ratios (organic C to ...

PURPOSE To unravel the cataractogenic process(es) leading to the birefringent lenticular bodies known as perinuclear retrodots. METHODS Ten human lenses containing biomicroscopically verified perinuclear retrodots were systematically screened and analyzed using scanning electron microscopy and energy dispersive x-ray microanalysis to verify their ultrastructure and elemental composition. RE...

Introduction Conclusions References Tables Figures

Physical, chemical, and mineralogical characteristics of six bentonites were assessed and related to their elemental release to wine. Extraction essays of bentonites in wine at three pH levels were carried out. The multielemental analysis of bentonites and wines was performed by atomic absorption spectrometry (AAS) and inductively coupled plasma mass spectrometry (ICP-MS). Bentonite addition re...