A rejoinder to "Psychotherapy research ethics: Continuing the debate on controlled clinical trials."

Responds to C. A. Heflinger's (1987) critique of the present authors (1986) by reiterating their concern for the principle of autonomy. The present authors note that all patients were fully informed about the research plan and their right to withdraw. Nonetheless, the ethical criticism offered by Heflinger regarding randomization cannot be entirely dismissed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Retinal adaptation to non-uniform fields: average luminance or symbol luminance?

Various lighting and video display terminal design recommendations have been based on the assumption that the eye adapts to the average luminance of the field being viewed. Other evidence suggests that for irregular patterns the eye adapts to a level biased toward the peak luminance in the field being viewed. Subjects in this study adapted to uniform fields of varying average luminance and to two test patterns, one of which (dots) had a peak luminance equal to the brightest uniform field and an average luminance equal to the least bright uniform field. Time, to respond to a test pattern following adaptation to dots was intermediate between the two extreme uniform fields, but closer to that of the brighter field which had an average luminance equal to the test pattern's peak luminance. For that reason, proposed lighting differences based on image polarity or recommendations of positive image polarity do not appear to be warranted.     

Human Resource Planning: A Business Necessity

Abstract

Information-based organizations are structured to function with as small and efficient a staff as possible. To this end, executives at The Promus Companies are using IT to spread decision-making authority and responsibility for customer satisfaction and customer service throughout the organization.     

Real-time motion segmentation of sparse feature points at any speed.

We present a real-time incremental approach to motion segmentation operating on sparse feature points. In contrast to previous work, the algorithm allows for a variable number of image frames to affect the segmentation process, thus enabling an arbitrary number of objects traveling at different relative speeds to be detected. Feature points are detected and tracked throughout an image sequence, and the features are grouped using a spatially constrained expectation-maximization (EM) algorithm that models the interactions between neighboring features using the Markov assumption. The primary parameter used by the algorithm is the amount of evidence that must accumulate before features are grouped. A statistical goodness-of-fit test monitors the change in the motion parameters of a group over time in order to automatically update the reference frame. Experimental results on a number of challenging image sequences demonstrate the effectiveness and computational efficiency of the technique.     

Analysis of long flow lines with quality and operational failures

This paper presents approximation methods for the performance analysis of long manufacturing lines, i.e. lines with more than two machines and one buffer, that have both quality and operational failures. We describe three different versions of long flow lines that differ in the locations of the inspection stations and in the sets of machines that each inspection station monitors. We explain a transformation method that approximates long manufacturing lines that have quality and operational failures with long lines that only have operational failures. Such lines can be evaluated by decomposition methods. We introduce other approximations to quantify the effects of the separation of inspections from operations. Comparison with simulation shows that the solution methods provide reliable performance estimates.     

Commentary on Meehl and Waller's (2002) Path Analysis and Verisimilitude.

P. E. Meehl and N. G. Waller's (see record 2002-18342-001) proposed method may not yield unique solutions for model parameters nor unique solutions for model lack of fit. The author argues from a naturalistic-cognitive philosophy of science that science seeks objective knowledge and that hypothesis testing is central to achieving that goal. It is also argued that P. E. Meehl and N. G. Waller's proposal blurs the distinction between hypothesis testing and explorations of the data seeking an optimal model to serve as a prospective inductive generalization. But it is noted that inductive generalizations are never unique and must be tested to eliminate those that reflect subjective aspects of the researcher's methods and points of view. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A note on validity generalization procedures.

Reviews validity generalization (VG) procedures and finds them to be subject to the logical fallacy of "affirming the consequent." It is argued that alternative models may explain variation in validity coefficients as well as the cross-situational consistency model espoused by many users of the VG approach. Moreover, some of the assumptions that form the statistical foundation of VG work are open to question. It is suggested that Fisher z transformations, which remove most of these problems and usually produce more conservative estimates of the degree to which sampling error may account for variability in correlations, be used. It is also recommended that a more stringent criterion than the 75% decision rule for rejecting the situational specificity hypothesis be used. (64 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

"Debunking myths about self-quitting: Evidence from 10 prospective studies of persons who attempt to quit smoking by themselves": Reply.

Replies to the comments of S. Cohen et al (see record 1990-05833-001) concerning S. Schachter's (see record 1982-30809-001) study on smoking cessation. Schachter agrees that Cohen's data are evidence that self-selected, hard-core smokers are indeed hard-core smokers, but questions what this has to do with self-quitting over time in the general population. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Three-Dimensional Visualization of Transgenic Tobacco Leaves

We have done a three-dimensional visualization of transgenic tobacco (Nicotiana tabacum) leaves for the study of chloroplast gene expression and regulation. The aim was to visualize tobacco leaves shot with tungsten particles. These tungsten particles were coated with the foreign DNA and shot into the leaf using the biolistic technique of DNA insertion. The visualization can be used to examine the leaves to gauge the efficiency of the shooting process, i.e.,to see what parts of the leaves have been effectively penetrated by the DNA-coated tungsten particles and also to judge the depth of penetration. The image data for the 3D visualization was collected at planes 10 microns apart, using a prototype version of a High Numerical Aperture Reflecting Microscope. The raw image data collected from the microscope was restored using the Row Action Projection (RAP) algorithm and the Partial Minimization and Constrained Iteration (PCMI) algorithm. These restored images were then used for 3D visualization using the Visualization Toolkit.     

Expression of the serine rich Entamoeba histolytica protein (SREHP) in the avirulent vaccine strain Salmonella typhi TY2 chi 4297 (delta cya delta crp delta asd): safety and immunogenicity in mice

Infection by the intestinal protozoan parasite Entamoeba histolytica remains a significant threat to health in much of the world. Here we describe the successful expression of the serine rich Entamoeba histolytica protein (SREHP), a protective antigen of ameba, in an attenuated vaccine strain Salmonella typhi TY2 chi 4297 (delta cya delta crp delta asd). The attenuation of S. typhi TY2 chi 4297 was not altered by expression of the SREHP-maltose binding protein (MBP) fusion protein and mice parenterally vaccinated with S. typhi TY2 chi 4297 expressing SREHP-MBP developed serum anti-amebic and anti-LPS antibodies. S. typhi TY2 chi 4297 expressing SREHP-MBP represents a prototype combination vaccine designed to prevent both amebiasis and typhoid fever.