Woven Coded CPFSK With Hierarchical Code Structure

We introduce hierarchical woven coded continuous phase frequency-shift keying (hierarchical WCCPFSK) as the serial concatenation of different outer convolutional codes and inner CPFSK. We compare it to WCCPFSK with identical outer convolutional codes. With the proposed code combinations, hierarchical WCCPFSK achieves superior decoding capability. Simulations show that it performs better at medium SNRs.     

Urinary 2-ethyl-3-oxohexanoic acid as major metabolite of orally administered 2-ethylhexanoic acid in human

Human metabolism of 2-ethylhexanoic acid (2-EHA), which is a known metabolite of important phthalates, was investigated using 2-EHA-contaminated food. The results of our studies reveal that the major catabolic pathway of 2-EHA in human is beta-oxidation. The dominant final urinary metabolite was identified and quantified as 3-oxo-2-ethylhexanoic acid (3-oxo-2-EHA), but only after immediate methylation of the extract from urine and prior to GC-MS analysis. Former studies without the precaution of immediate methylation had found 4-heptanone as the major metabolite, which is obviously an artifact arising from the decarboxylation of 3-oxo-2-EHA.