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Biomedical subjects

D D Woods

Publications and source records attributed to D D Woods.

15 recordsLinked to original sources
PubMed1992

Cognitive simulation as a tool for cognitive task analysis.

Cognitive simulations are runnable computer programs that represent models of human cognitive activities. We show how one cognitive simulation built as a model of some of the cognitive processes involved in dynamic fault management can be used in conjunction with small-scale empirical data on human performance to uncover the cognitive demands of a task, to identify where intention errors are likely to occur, and to point to improvements in the person-machine system. The simulation, called Cognitive Environment Simulation or CES, has been exercised on several nuclear power plant accident scenarios. Here we report one case to illustrate how a cognitive simulation tool such as CES can be used to clarify the cognitive demands of a problem-solving situation as part of a cognitive task analysis.

Cognition↗
PubMed1991

Evaluating the human engineering of microprocessor-controlled operating room devices.

Although human engineering features are widely appreciated as a potential cause of operating room incidents, evaluating the human engineering features of devices is not widely understood. Standards, guidelines, laboratory and field testing, and engineering discipline are all proposed methods for improving the human engineering of devices. New microprocessor technology offers designers great flexibility in the design of devices, but this flexibility is often coupled with complexity and more elaborate user interaction. Guidelines and standards usually do not capture these features of new equipment, in part because technology improvements occur faster than meaningful guidelines can be developed. Professional human engineering of new devices relies on a broad, user-centered approach to design and evaluation. Used in the framework of current knowledge about human operator performance, these techniques offer guidance to new equipment designers and to purchasers and users of these devices.

Anesthesiology↗
PubMed1979

Signal detection in computer-synthesized noise.

Human observers detected sinusoidal and pulse-train signals in noise derived from two computer-synthesized sources and from a Gaussian noise source. The synthesized noise stimuli were generated from sequences of pulses whose amplitudes were drawn from two divergent types of probability distributions: a centrally peaked distribution and a bimodal distribution. No differences in the detectability of signals in these noise stimuli were evident at pulse rates of 1000, 2000, 4000, or 10 000 Hz. subjects could not discriminate between the two types of computer-generated maskers at any pulse rate. The data support a spectrum-analyzer model of detection in which multiband filtering of the input smooths the masker energy in each spectral region to approximate the Gaussian case.

Computers↗
PubMed1978

Cellular and humoral responses to myelin basic protein in multiple sclerosis: a dichotomy.

The macrophage migration inhibition factor (MIF) assay and a counterimmunodiffusion assay were utilized to measure immune responses to human myelin basic protein in 75 patients with multiple sclerosis (MS) and in 120 control subjects. Eight out of ten MS patients in acute exacerbation and one out of seventeen convalescent, but none of chronically ill MS patients gave positive results in the MIF test. Forty-six percent of the patients with negative MIF assays but only 22% of those with positive assays had positive antibody results. In the counterimmunodiffusion assay, myelin basic protein antibody was demonstrated in almost 2/3 of patients during convalescence but it was not present in those whose illness had been stable for 6 months or longer. While no correlation with the stage or duration of the illness was present in other disorders, in MS an inverse correlation with clinical activity and in vitro evidence of cellular sensitization to encephalitogenic basic protein was apparent.

Autoantibodies↗
PubMed1966

Methionine synthesis by extracts of Salmonella typhimurium.

1. Following the genetic studies by Smith (1961) and Smith & Childs (1963) with methionine auxotrophs of Salmonella typhimurium, methionine formation from homocysteine has been investigated with cell-free extracts of this organism. 2. As found with Escherichia coli (Woods, Foster & Guest, 1964), methyl groups are formed by an N(5)N(10)-methylenetetrahydrofolate reductase. They are then transferred to homocysteine by either a simple N(5)-methyltetrahydropteroyl-triglutamate-homocysteine methyltransferase or alternatively a cobalamin-dependent N(5)-methyltetrahydrofolate-homocysteine methyltransferase. 3. S. typhimurium differs from E. coli in being able to synthesize significant amounts of cobalamin.

Alcohol Oxidoreductases↗