Non-equilibrium dynamics as an indispensable characteristic of a healthy biological system

Healthy systems in physiology and medicine are remarkable for their structural variability and dynamical complexity. The concept of fractal growth and form offers novel approaches to understanding morphogenesis and function from the level of the gene to the organism. For example, scale-invariance and long-range power-law correlations are features of non-coding DNA sequences as well as of healthy heartbeat dynamics. For cardiac regulation, perturbation of the control mechanisms by disease or aging may lead to a breakdown of these long-range correlations that normally extend over thousands of heartbeats. Quantification of such long-range scaling alterations are providing new approaches to problems ranging from molecular evolution to monitoring patients at high risk of sudden death. We briefly review recent work from our laboratory concerning the application of fractals to two apparently unrelated problems: DNA organization and beat-to-beat heart rate variability. We show how the measurement of long-range power-law correlations may provide new understanding of nucleotide organization as well as of the complex fluctuations of the heartbeat under normal and pathologic conditions.     

Persons and their Properties

According to what I call 'the asymmetry thesis', persons, though they are the direct bearers of the properties expressed by mental predicates, are not the direct bearers of properties such as those expressed by 'weighs 135 pounds' or 'has crossed legs'. A number of different views about persons entail the asymmetry thesis. I first argue that the asymmetry thesis entails an error theory about our discourse involving person-referring terms. I then argue that it is further threatened by consideration of the grounds we have for self-ascribing mental and physical predicates.     

Female business owners in industries traditionally dominated by males

This study examined selected demographics, personality traits, and job-related characteristics of females and males operating small businesses in traditionally male-dominated industries. Of the 56 participating businesses owners, all but 2 were Caucasian. Organizational characteristics were also observed. Significant gender differences were found in marital status, industry experience, age of firms, number of females hired, and effectiveness of communication scores.     

An Excel macro for transformed and weighted averaging

An Excel macro is presented for averaging spreadsheet data. The macro has several special features: (1) The data are weighted by the inverse variance of each datum to decrease the contribution-of noisy outliers. (2) There is a provision for a power or a log transform of the data before averaging. The rationale for transforming the data before averaging is discussed (3) The output includes the average value, its standard error, and the reduced chi-square that measures the goodness of fit (4) The standard error is corrected by a heterogeneity factor based on the reduced chi-square The averaging of data is rarely done properly, and the intent of this article is to clarify the issues and provide a tool that allows researchers to improve their averaging techniques.     

Prediction of Task-Related Arousal Under Conditions of Environmental Distraction1

The Arousability Predisposition Scale (APS) was used to assess individual differences in arousal that occur when a task is performed under conditions of environmental distraction. The APS is a brief (12-item) scale, that purportedly measures arousability as a trait or predisposition. To manipulate arousal experimentally, subjects performed a speeded search task under conditions of visual and auditory distraction. Pre- and postdistraction task measures of arousal were taken using Thayer's Activation-Deactivation Adjective Check List. The distraction task caused a general increase in arousal as compared to a control group who did not perform the task. Although there were no differences in pretest measures, subjects judged highly arousable on the APS showed a greater change in task-related arousal than subjects judged low on arousability, validating the usefulness of the APS as a measure of arousability under conditions of environmental stress.     

Attention and automaticity: Toward a theoretical integration

We sketch an initial version of a theory intended to account for the role of attention in the acquisition and expression of automaticity, and we test some initial predictions. The theory combines Logan's instance theory of automaticity and Bundesen's theory of visual attention, with Bundesen's theory determining what Logan's theory learns. We report four experiments that test the assumption that subjects learn what they report explicitly do not learn what they do not report explicitly. The experiments provide partial support for the predictions and encourage further development of the combined theory. Received: 4 September 1997 / Accepted: 12 January 1998