Comparison of CID, ETD and metastable atom-activated dissociation (MAD) of doubly and triply charged phosphorylated tau peptides.

The fragmentation behavior of the 2+ and 3+ charge states of eleven different phosphorylated tau peptides was studied using collision-induced dissociation (CID), electron transfer dissociation (ETD) and metastable atom-activated dissociation (MAD). The synthetic peptides studied contain up to two known phosphorylation sites on serine or threonine residues, at least two basic residues, and between four and eight potential sites of phosphorylation. CID produced mainly b-/y-type ions with abundant neutral losses of the phosphorylation modification.

Classification of jet fuels by fuzzy rule-building expert systems applied to three-way data by fast gas chromatography--fast scanning quadrupole ion trap mass spectrometry.

A fast method that can be used to classify unknown jet fuel types or detect possible property changes in jet fuel physical properties is of paramount interest to national defense and the airline industries. While fast gas chromatography (GC) has been used with conventional mass spectrometry (MS) to study jet fuels, fast GC was combined with fast scanning MS and used to classify jet fuels into lot numbers or origin for the first time by using fuzzy rule-building expert system (FuRES) classifiers. In the process of building classifiers, the data were pretreated with and without wavelet transformation and evaluated with respect to performance.

Gas chromatography tandem mass spectrometry for biomarkers of alcohol abuse in human hair.

We present the development of a new, faster analytical method for the determination of fatty acid ethyl esters (FAEEs) in human hair to detect potential alcohol abuse. FAEEs have been established as metabolites of ethanol consumption in humans and are embedded in the hair follicles during hair growth. The developed method has a total analysis time-including washing, extraction, concentration, separation, and detection-of less than 1 hour.

Analysis of suspected trace human remains from an indoor concrete surface.

This paper describes the sequence of analyses used to determine the nature of a stain located on the floor of room in the former Athens Mental Health and Retardation Hospital in Athens, OH. The location of the stain was reported to be the position in which a decomposing body was discovered on January 11, 1979. The current stain is found to contain strong evidence for both natural decomposition products and deliberate adulteration.