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Biomedical subjects

P R Swank

Publications and source records attributed to P R Swank.

17 recordsLinked to original sources
PubMed1992

Teacher interactions in mainstream social studies and science classes.

This investigation was designed to change teacher-student interactions in middle school social studies and science classes. Eighteen of 35 teacher volunteers received a six-session inservice emphasizing teacher effectiveness variables. Results indicated significant differences between experimental and control teachers on a pre-post contrast, as well as on a follow-up (maintenance) contrast. Differential effects on the science and social studies teachers were seen. Similarities and differences related to student type, independent of the intervention, were obtained.

Child↗
PubMed1991

A computer program for microplate reader interface and analysis of kinetic, microclot lysis assays.

This paper describes the development and use of a program for the APPLE IIe computer which records and analyzes data from an automated microplate reader for the purpose of determining the time required for clots formed in microplate wells to half lyse as determined by optical density readings. The use of this software has led to significant savings of technician time over that required for nonautomated systems.

Electronic Data Processing↗
PubMed1991

Crisis intervention: long-term training effects.

10 months following a crisis-intervention training program which focused on interpretation of signal events, 17 participants more frequently reported increased belief in their ability to recognize the need for intervention and to intervene effectively than did 22 control subjects. Perceived frequency of intervention by trained participants, however, had decreased rather than increased. Implications of the findings and recommendations for research are discussed.

Adult↗
PubMed1990

Parallel line analysis: multifunctional software for the biomedical sciences.

An easy to use, interactive FORTRAN program for analyzing the results of parallel line assays is described. The program is menu driven and consists of five major components: data entry, data editing, manual analysis, manual plotting, and automatic analysis and plotting. Data can be entered from the terminal or from previously created data files. The data editing portion of the program is used to inspect and modify data and to statistically identify outliers. The manual analysis component is used to test the assumptions necessary for parallel line assays using analysis of covariance techniques and to determine potency ratios with confidence limits. The manual plotting component provides a graphic display of the data on the terminal screen or on a standard line printer. The automatic portion runs through multiple analyses without operator input. Data may be saved in a special file to expedite input at a future time.

Data Interpretation, Statistical↗
PubMed1989

Identification of features of metaplastic cells in sputum for the detection of squamous-cell carcinoma of the lung.

Digitized images of 1,556 squamous metaplastic cells from the sputum of 15 patients with confirmed squamous-cell carcinoma of the lung and 13 subjects without apparent neoplasia were analyzed to determine if features existed within these relatively normal cells that could be used to differentiate between the two populations. Results indicate that such marker features do exist. A cross-validation study using an additional 465 cells confirmed the conclusion that squamous metaplastic cells from patients with squamous-cell carcinoma of the lung do differ from those of subjects without cancer. While such marker features alone are not reliable enough to assist pathologists in the diagnosis of squamous-cell carcinoma of the lung, they might, in sufficient numbers, be used to identify patients for whom follow-up testing would be advised.

Biomarkers, Tumor↗
PubMed1988

The use of a pragmatic protocol with normal preschool children.

The purpose of the present study was to examine the use of language functions in a structured setting in normal preschool children. Subjects were 240 males and females between the ages of two and five years. Results indicated statistically significant differences in the appropriateness of responses among several different age groups. The results are discussed relative to the assessment of the preschool child with a possible language disorder.

Child, Preschool↗
PubMed1987

The reliability of cytopathologists' classifications of bronchial epithelial atypias from Kodachrome slides.

The accuracy of computerized cell image analysis techniques for classification of atypical cells is determined by comparing computer-generated classifications with those made by cytopathologists. This measure of accuracy depends not only on the reliability of the computer classifications but also on the reliability of the cytopathologists' classifications. This study reports on the observed reliability of cytopathologists' classifications of squamous epithelial atypias in sputum across cytopathologists and two different classification times. Results indicated the percentage agreement among cytopathologists and computerized cell image analysis techniques. It is recommended that, in the future, all analyses of computerized classification schemes by interpreted in light of the consistency of the cytopathologists' classifications.

Diagnosis, Computer-Assisted↗
PubMed1984

Precision cell location and relocation techniques. An application for cell image analysis.

Two methods for precise cell location and relocation were developed at the Cell Image Analysis Laboratory, NASA, to increase the efficiency of the cell image acquisition process. The first method uses a Zeiss Zonax with a 10 micron scanning stage and automatically records cell coordinates on 5.25-inch floppy disks. The second method uses a Digital Positioning Device with a 10 micron scanning stage, and the cell coordinates displayed on light-emitting diodes (LEDs) are recorded manually. Because of its superior speed and automation, the Zonax was selected as the method of choice. By using a Zonax for off-line cell location and another Zonax for on-line cell relocation, more than three times the number of digitized images were collected in ten months than in the previous three years. Other beneficial applications of the cell location and relocation methods were realized in photomicrography, data base verification and cytopathology.

Computers↗
PubMed1983

Nuclear segmentation of bronchial epithelial cells by minimax and thresholding techniques. A comparison.

Two nuclear segmentation methods, Baky's minimax algorithm and thresholding, were compared on a sample of 879 atypical bronchial epithelial cells in sputum. Nuclear-cytoplasmic (N/C) ratios for all cells were determined by each segmentation method and compared to a visually determined value. Cells were categorized by atypia class (from metaplastic through malignant), by staining characteristics (orangeophilic and nonorangeophilic) and by method of digitization (either scanning microphotometry or video system). The method of digitization was confounded by subject differences. The results indicated that with most classes of atypia, N/C ratios determined by minimax were closer to the visually derived values than were those of thresholding, particularly with orangeophilic cells. Both methods become progressively less accurate, as compared to the visual procedure, as the degree of atypia increases.

Bronchi↗
PubMed1983

Classification of bronchial epithelial atypias by the atypia status index.

The atypia status index (ASI) is a categorization method of classifying digitized images of atypical bronchial epithelial cells in sputum. The ASI is defined as a linear composite of features linearly related to atypia stage. Over 200 features were examined for more than 3,000 cells that had been classified by atypia stage (squamous metaplasia, mild, moderate or severe atypia and malignant) and staining characteristic (orangeophilia and nonorangeophilia). We reduced the number of features by using a selection process to minimize redundancy. The feature weights were optimized via a least-squares procedure. The 14 features selected accounted for over 60% of the variation of atypia stage and produced ASI values that were within one atypia stage of the criterion classification for over 90% of the cells. The results are consistent with the hypothesis of a progressive pattern in bronchial epithelial atypia and indicate the feasibility of using image analysis for mass screening of premalignant atypias in sputum from subjects considered to be at high risk for lung cancer.

Adult↗
PubMedDate not supplied

Application of cell-image analysis to the diagnosis of cellular atypias in sputum: a review.

The incidence of carcinoma of the lung continues to steadily rise, and attempts at early diagnosis to improve prognosis have not yet been rewarding. The goal of our research is to decrease the incidence of lung cancer by detecting premalignant bronchial dysplasias in individuals in whom development of lung cancer is potentially preventable. To achieve this, we have developed an atypia status index (ASI)--the assignment of numerical values to the various stages of atypical bronchial epithelial cells in sputum, and a cell atypia profile (CAP)--an ASI-generated scale of 200 such atypical bronchial epithelial cells in a single sputum specimen. Computerized cell-image analysis techniques and statistical data analysis are used to generate the ASIs and CAPs for each subject. This study is a step toward the development of an automated cell-image analysis system for mass screening of premalignant atypias in sputum of those considered at high risk for lung cancer (i.e., men and women of 40 yr of age and older, with more than 20 pack-yr of cigarette smoking).

Adult↗
PubMedDate not supplied

Correlates of postsecondary employment outcomes for young adults with learning disabilities.

The purpose of this study is twofold: (a) to examine the efficiency of a set of selected variables for predicting postsecondary employment success for young adults classified as learning disabled in high school and (b) to provide a portrayal of employment adjustment in the first years after exiting high school. Data on both employment stability and job status were gathered through telephone interviews. Of the 284 students with learning disabilities who exited the four participating high schools between 1986 and 1989, contact was made with 175 (62%). This sample was composed of 75% males, who ranged in age from 18 to 23 years. Statistical tests reveal that students (a) with high math ability, (b) who were employed during high school, and (c) whose parents actively participated in their education were more likely to experience employment success after high school. Overall, 86% of the sample was employed either full- or part-time, with the majority in entry-level, unskilled jobs. In terms of postsecondary education, 26% completed at least one semester of college or technical school, though at the time of follow-up only 13% were enrolled in school.

Adolescent↗
PubMedDate not supplied

The application of visual cell profiles in the study of premalignant atypias in sputum.

Because the diagnosis of squamous-cell carcinoma of the lung by routine cytologic screening of sputum is often inconclusive, our laboratory is studying the use of cytomorphologic profiles as a reliable diagnostic aid. This study reports the analysis of the profiles of 75 subjects, both cigarette-smoking volunteers and hospitalized patients suspect for lung cancer. Twenty-five of the subjects had been classified as having squamous metaplasia, 25 as having atypias and 25 as having squamous-cell carcinoma. Four slides were made for each subject, with 100 random fields viewed on each slide. The frequency of free alveolar macrophages, metaplastic squamous cells, epithelial atypical cells and malignant squamous cells were noted for each field. The results indicated that, although there were large differences between individual profiles within each diagnostic category, there were significant differences between the average profiles for each diagnostic category. Furthermore, although there were differences in cell frequencies from slide to slide and within slides, the differences were constant across diagnostic categories. The results are supportive of the progressive-atypia hypothesis for squamous-cell carcinoma of the lung and provide a baseline for comparison with subsequent individual profiles.

Carcinoma↗
PubMedDate not supplied

Visual cell profiles for quantitation of premalignant cells in sputum: a preliminary report.

Visual cell profiles were used to analyze the distribution of atypical bronchial cells in sputum specimens from cigarette-smoking volunteers, cigarette-smoking asbestos workers and cigarette-smoking uranium miners. The preliminary results of these sputum visual cell profile studies have demonstrated distinctive distributions of bronchial cell atypias in progressive patterns of squamous metaplasia, mild, moderate and severe atypias and carcinoma, similar to those the authors have previously reported using cell image analysis techniques to determine an atypia status index (ASI). The information gained from this study will be helpful in further validating this ASI and subsequently achieving the ultimate goal of employing cell image analysis for the rapid and precise identification of premalignant atypias in sputum.

Age Factors↗