Given a wavelet w and a noisy trace t + s * w + n, an approximation ŝ of the spike train s can be obtained using the [Formula: see text] norm. This extraction has the advantage of preserving isolated spikes in s. On some types of data the spike train ŝ can represent s as a sparse series of spikes, which may be sampled at a rate higher than the sample rate of the data trace t. The extracted spike train ŝ may be qualitatively much different than those commonly extracted using the [Formula: see text] norm. The [Formula: see text] norm can also be used to extract a wavelet ŵ from a trace t when a spike train s is known. This wavelet extraction can be constrained to give a smooth wavelet which integrates to zero and goes to zero at the ends. Given a trace t and an initial approximation for either s or w, it is possible to alternately extract spike trains and wavelets to improve the representation of trace t. Although special algorithms have been developed to solve [Formula: see text] problems, all of the calculations can be performed using a general linear programming system. Proper weighting procedures allow these methods to be used on ungained data.

In 2000, soldiers from a Special Operations Force had airborne lead exposures 20 to 38 times the permissible exposure limit. Their average blood lead level was 13.9 microg/dL. Immediate implementation of pertinent Occupational Safety and Health Administration regulations was recommended. In 2003, investigators learned that the unit also used an outdoor firing range with exposures exceeding the permissible exposure limit. Attempts to conduct more detailed evaluations and control measures were hindered by frequent deployments in the unit and a strong commitment to realistic training. Despite these challenges, the controls implemented resulted in limited success. The average blood lead level in the unit was 6.8 microg/dL in 2005, a reduction of 51%. Proper initial range construction is essential to controlling lead exposures at firing ranges. Occupational health specialists caring for these soldiers must identify, assess, and mitigate exposures from firing ranges while respecting the importance of realistic training.

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