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H T Nagle

Publications and source records attributed to H T Nagle.

4 recordsLinked to original sources

Effect of environmental pollutants on taste and smell.

Various man-made and naturally occurring chemicals and substances can modify the chemosensory systems of animals and man. This article provides an overview of research studies that investigate the impact of pollution on taste and smell perception. Acute and chronic alterations in taste and olfaction are discussed for solvents, herbicides, fungicides, pesticides, disinfectants, germicides, soil fumigants, dyes, pharmaceuticals, textile wastes, smog, tobacco smoke, perfumes, flavors, plastics, synthetic rubber, and other industrial substances. The mechanisms by which pollutants may cause physiologic and biologic changes are highlighted. Natural detoxification systems are discussed, as well as treatments for chemosensory deficits.

Air Pollutants

A comparison of the noise sensitivity of nine QRS detection algorithms.

The noise sensitivities for nine different QRS detection algorithms were measured for a normal, single-channel lead II, synthesized ECG corrupted with five different types of synthesized noise. The noise types were electromyographic interference, 60 Hz powerline interference, baseline drift due to respiration, abrupt baseline shift, and a composite noise constructed from all of the other noise types. The percentage of QRS complexes detected, the number of false positives, and the detection delay were measured. None of the algorithms were able to detect all QRS complexes without any false positives for all of the noise types at the highest noise level. Algorithms based on amplitude and slope had the highest performance for EMG-corrupted ECG. An algorithm using a digital filter had the best performance for the composite noise corrupted data.

Algorithms

A Monte Carlo technique for signal level detection in implanted intracranial pressure monitoring.

Statistical monitoring techniques like CUSUM, Trigg's tracking signal and EMP filtering have a major advantage over more recent techniques, such as Kalman filtering, because of their inherent simplicity. In many biomedical applications, such as electronic implantable devices, these simpler techniques have greater utility because of the reduced requirements on power, logic complexity and sampling speed. The determination of signal means using some of the earlier techniques are reviewed in this paper, and a new Monte Carlo based method with greater capability to sparsely sample a waveform and obtain an accurate mean value is presented. This technique may find widespread use as a trend detection method when reduced power consumption is a requirement.

Biomedical Engineering