Eugene P. Wagner

A history and review of quantitative electroencephalography in traumatic brain injury.

The electroencephalogram (EEG) is a physiologic measure of cerebral function that has been used by some to assess coma and prognosticate survival and global outcome after traumatic brain injury (TBI). Surface recordings of the brains electrical activity reveal distinct patterns that indicate injury severity, depth of unconsciousness, and patient survival. The data produced with traditional qualitative studies, however, does not allow resolution and quantification of the wave frequency spectrum present in the brain. As a result, conventional EEG typically has only been used for gross and qualitative analyses and is not practical for use in long-term patient monitoring or as a sophisticated prognostic tool. One area of investigation that is working to address the limitations of conventional EEG has been the development and implementation of Fourier Transform (FT) EEG which resolves and quantifies frequency bands present in the brain. When FT analysis is applied to EEG, it provides concurrent and continuous monitoring, resolution, and quantification of all frequencies emitted. This review discusses the history and significance of conventional EEG and provides a review of how FT-EEG, commonly referred to as Quantitative EEG (QEEG), is being used in the clinical setting. The specific applications and significance of QEEG methods regarding treatment of patients with TBI are discussed in detail. The advantages, disadvantages, and future directions of QEEG in TBI are also discussed.

Construction and Evaluation of a Visible Spectrometer Using Digital Micromirror Spatial Light Modulation

Digital micromirror devices (DMDs), also known as spatial light modulators, have been produced in a wide variety of configurations specific to their applications such as joint-transform correlator systems, optical neural networks, and high-definition televisions. The characteristics of DMD technology and flexibility of design lend themselves to a new application in optical spectrometers. Medium-resolution optical spectrometers, with a spectral bandwidth on the order of 1 nm, are widely used in instrumentation designed to record molecular absorption spectra in the ultraviolet and visible regions and are among the most widely used laboratory instruments. Modern UV-visible spectrometers usually are designed to use a multichannel detector, such as a photodiode array (PDA), in conjunction with a compact fixed-resolution spectrograph and can record spectra with reasonable speed, ∼ 30 ms. These spectrographs have no moving parts and are used for on-line detection of chromatographic eluents, for routine analytical determinations, and for industrial applications such as measurements made in process streams. However, diode array detectors are generally more expensive and are less sensitive than photomultiplier tubes (PMTs), particularly in the UV, and require cooling when a long integration time and low dark current are necessary. In addition, the diode array cannot acquire spectra fast enough for most kinetic studies to be made. A medium-resolution spectrometer which incorporates DMD technology and a PMT for detection has the potential of obtaining a spectrum on the order of a few milliseconds with high sensitivity at a lower cost than that for current PDA or charged-coupled device (CCD) spectrometers. Another advantage of the DMD spectrometer is that it possesses the capability of repetitively scanning a small portion of the spectrum without collecting the entire spectrum (random pixel access). The high sensitivity of a DMD spectrometer using a PMT also makes it ideal for fluorescence and phosphorescence detection.

Status of and perspectives on microwave and glow discharges for spectrochemical analysis. Plenary lecture

Glow discharge atomic emission and atomic fluorescence and microwave plasma atomic emission spectrometric methods are reviewed and compared with the conventional atomic approaches of electrothermal atomization atomic absorption spectrometry, inductively coupled plasma atomic emission spectrometry, and inductively coupled plasma mass spectrometry. Diagnostical characteristics and analytical figures of merit are given for a number of plasma types and spectrometric methods, respectively. Theoretical efficiencies of detection and measurement are given for the glow discharge and microwave plasma methods. Quantitation methods are discussed and future predictions of a number of atomic spectrometric methods are given in tabular form.

Determination of silicate by hollow cathode glow discharge-atomic emission spectrometry with hydride generation technique

Abstract Hollow cathode glow discharge atomic emission spectrometry has been applied to the determination of silicon coupled with a novel gaseous hydride generation technique, involving drying of an aqueous solution of silicate (sample) and mixing with powdered LiAlH4. Sample introduction into the glow discharge chamber was performed via a pinhole at the center of the cathode which was connected to the hydride generator. The detection limit for silicon was 6μg at 288.1 nm and 30 μg at 251.6 nm. ∗ on leave from Faculty of Integrated Arts and Sciences, Hiroshima University, Higashi-Hiroshima, 739, Japan

Measuring rehabilitation research capacity: report from the AAPM&R Research Advisory Committee.

Wagner AK, McElligott J, Wagner II EP, Gerber LH: Measuring rehabilitation research capacity: Report from the AAPM&R research advisory committee. Am J Phys Med Rehabil 2005;84:955–968. There is considerable concern regarding the paucity of individuals pursuing biomedical research in general and rehabilitation research in particular. The Research Advisory Committee (RAC) of the American Academy of Physical Medicine and Rehabilitation (AAPM&R) accepted the task to explore the barriers to biomedical research careers for physicians and rehabilitation scientists and, in particular, those factors pertaining to successfully conducting rehabilitation research. Concurrently, the Foundation for PM&R was also exploring the related issue of building capacity for rehabilitation research and planning a Rehabilitation Research Summit to address this issue for the spring of 2005. The goals of the Research Summit included the identification of barriers to rehabilitation research and development of an active agenda to enhance research capacity. As such, AAPM&R and the Foundation for PM&R worked through the RAC survey to provide some key information that would help the summit leaders achieve their goals. This report presents portions of the survey related to research capacity and outlines the methodology of the data collection and analysis within the context of the capacity taxonomy framework as presented at the Research Summit, “Building Research Capacity,” held in the spring of 2005. This survey report provides quantitative information about researchers and academicians, their research environment, as well as their barriers and incentives for conducting rehabilitation research. Observations here provide a platform for future work in understanding the adequacy of the rehabilitation research enterprise, its appropriateness, and ability to meet societal needs for those with disabilities