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Biomedical subjects

B L Hopkins

Publications and source records attributed to B L Hopkins.

At least 19 recordsLinked to original sources
PubMed2004

DNA sequence and analysis of human chromosome 9.

Chromosome 9 is highly structurally polymorphic. It contains the largest autosomal block of heterochromatin, which is heteromorphic in 6-8% of humans, whereas pericentric inversions occur in more than 1% of the population. The finished euchromatic sequence of chromosome 9 comprises 109,044,351 base pairs and represents >99.6% of the region. Analysis of the sequence reveals many intra- and interchromosomal duplications, including segmental duplications adjacent to both the centromere and the large heterochromatic block. We have annotated 1,149 genes, including genes implicated in male-to-female sex reversal, cancer and neurodegenerative disease, and 426 pseudogenes. The chromosome contains the largest interferon gene cluster in the human genome. There is also a region of exceptionally high gene and G + C content including genes paralogous to those in the major histocompatibility complex. We have also detected recently duplicated genes that exhibit different rates of sequence divergence, presumably reflecting natural selection.

Base Composition↗
PubMed2001

The physical maps for sequencing human chromosomes 1, 6, 9, 10, 13, 20 and X.

We constructed maps for eight chromosomes (1, 6, 9, 10, 13, 20, X and (previously) 22), representing one-third of the genome, by building landmark maps, isolating bacterial clones and assembling contigs. By this approach, we could establish the long-range organization of the maps early in the project, and all contig extension, gap closure and problem-solving was simplified by containment within local regions. The maps currently represent more than 94% of the euchromatic (gene-containing) regions of these chromosomes in 176 contigs, and contain 96% of the chromosome-specific markers in the human gene map. By measuring the remaining gaps, we can assess chromosome length and coverage in sequenced clones.

Chromosomes, Human, Pair 1↗
PubMed2001

A high-density transcript map of the human dominant optic atrophy OPA1 gene locus and re-evaluation of evidence for a founder haplotype.

Dominant optic atrophy (DOA, gene OPA1) is the commonest form of inherited optic atrophy. Linkage studies have shown that a locus for this disease lies in a 1.4-cM region at chromosome 3q28-->q29 and have suggested a founder haplotype for as many as 95% of the linked families. To aid the identification of candidate genes for this disease, we have constructed a Bacterial Artificial Chromosome (BAC) contig covering approximately 3.3 Mb and encompassing the OPA1 critical region (flanking markers D3S3669 and D3S3562). This physical map corrects errors in the marker order reported in the literature, allowing the OPA1 critical region to be precisely defined. A reassessment of the founder effect in the light of the revised marker order suggests that it may not be as significant as had previously been suggested. A high-density transcript map was created by precisely mapping genes and expressed sequence tags (ESTs) from GeneMap'99, that have been loosely assigned to the region by radiation hybrid mapping. One known gene (KIAA0567 protein) and 15 ESTs were found to lie within the minimal disease region. Analysis of the sequence data already available from within the OPA1 critical region allowed the identification and mapping of a further 31 ESTs. The work presented in this study provides the basis for the characterisation of candidate genes and the ultimate identification of the gene mutated in DOA.

Chromosomes, Artificial, Bacterial↗
PubMed2001

Documentation of hazards and safety perceptions for mechanized logging operations in East Central Alabama.

The logging industry remains one of the most hazardous in the nation. Despite more stringent safety regulations and improvements in equipment safety features, the rate of logging fatalities has decreased at a much lower rate than the decrease in the rate of illnesses and injuries in the same occupation. The objective of this research was to identify and assess the hazards associated with logging operations in the Southeast region of the U.S. and propose interventions, taking into consideration the fact that, currently, most operations in the region are fully mechanized. Five logging crews in East Central Alabama participated in the study and were observed repeatedly during their normal operations. Researchers observed loggers engaging in multiple unsafe behaviors, but none of those led to an injury. The incidence of unsafe behaviors may be due in part to a lack of awareness of the hazards. Results indicate that Occupational Safety and Health Administration (OSHA) regulations appear to have little influence on logging safety. Loggers believe that most safety training recommendations are difficult to implement and negatively impact productivity. Thus, there seem to be fundamental drawbacks in the logging industry regarding effective delivery of safety training to loggers. The present study was a joint venture by the Industrial and Systems Engineering and Psychology departments of Auburn University, with support from the United States Forest Service (USFS).

Accidents, Occupational↗
PubMed1999

Perception of quality of life of persons with HIV/AIDS and maintenance of nutritional parameters while on protease inhibitors.

This descriptive study investigated quality of life issues, biochemical indices, and nutritional parameters of individuals with HIV/AIDS before the initiation of protease inhibitors (PI) and after PI therapy. Telephone interviews were conducted with 45 men and women who were diagnosed with HIV/AIDS. A 26-item subjective questionnaire was used to determine intake of liquid nutritional supplements, use of micronutrient and herb supplements, adherence to modified diets, gastrointestinal symptoms, employment status, sociability, and ability to conduct activities of daily living. A medical chart review was conducted to collect data on biochemical indices, weight, medication regimens, and incidence of opportunistic infections. The results of the study suggest that HIV/AIDS individuals gain weight, improve CD4 counts, and decrease HIV RNA viral load while on PI-based drug combination therapy. Opportunistic infections decreased, quality of life was improved, and blood albumin was elevated. Hyperlipidemia, that is, elevations in total cholesterol and triglycerides, was observed in study participants (44% and 40% of patients, respectively) after PI therapy. These findings support the need for future investigations to examine the long-term influence of PI-based combination drug therapies on nutrient intake, body composition, and quality of life of persons with HIV/AIDS.

Acquired Immunodeficiency Syndrome↗
PubMed1995

Applied behavior analysis and statistical process control?

This paper examines Pfadt and Wheeler's (1995) suggestions that the methods of statistical process control (SPC) be incorporated into applied behavior analysis. The research strategies of SPC are examined and compared to those of applied behavior analysis. I argue that the statistical methods that are a part of SPC would likely reduce applied behavior analysts' intimate contacts with the problems with which they deal and would, therefore, likely yield poor treatment and research decisions. Examples of these kinds of results and decisions are drawn from the cases and data Pfadt and Wheeler present. This paper also describes and clarifies many common misconceptions about SPC, including W. Edwards Deming's involvement in its development, its relationship to total quality management, and its confusion with various other methods designed to detect sources of unwanted variability.

Behavior Therapy↗
PubMed1990

Empowering people with physical disabilities through advocacy skills training.

Members of an advocacy organization for people with physical disabilities were trained to identify and report issues at group meetings. In addition, two consecutive chairpersons were trained to conduct action-oriented meetings. Measures of group members' activities outside meetings and related outcomes on identified issues were also collected. Results indicated increases in the number of disability-related issues reported by trained members and consistent improvements in chairperson performance following training. Retrospective interviews and permanent records showed that advocacy activities, as well as the outcomes of members' actions, increased after training. These findings and their implications for the empowerment of people with disabilities are discussed.

Adult↗
PubMed1987

The long-term effects of a token economy on safety performance in open-pit mining.

A token economy that used trading stamps as tokens was instituted at two dangerous open-pit mines. Employees earned stamps for working without lost-time injuries, for being in work groups in which all other workers had no lost-time injuries, for not being involved in equipment-damaging accidents, for making adopted safety suggestions, and for unusual behavior which prevented an injury or accident. They lost stamp awards if they or other workers in their group were injured, caused equipment damage, or failed to report accidents or injuries. The stamps could be exchanged for a selection of thousands of items at redemption stores. Implementation of the token economy was followed by large reductions in the number of days lost from work because of injuries, the number of lost-time injuries, and the costs of accidents and injuries. The reductions in costs far exceeded the costs of operating the token economy. All improvements were maintained over several years.

Accident Prevention↗
PubMed1986

Effective and reliable behavioral control technology.

The fiberglass-reinforced plastics industry and the literature on controlling exposures to toxic substances were surveyed to select work practices and housekeeping conditions that might be useful in reducing workers' exposures to styrene. A training program was developed to teach the selected behaviors to workers, and a behavior maintenance program was developed to encourage their continued use after training. These behavioral controls were introduced to appropriate workers in three different plants and were effective in changing all selected behaviors and conditions. Statistically reliable reductions in workers' exposures to styrene accompanied the changes in behaviors. All improvements were maintained throughout the course of data collection. The research provides a clear demonstration that behavioral controls can be used reliably to reduce workers' exposures to toxic substances.

Behavior Therapy↗
PubMed1986

Behavioral technology for reducing occupational exposures to styrene.

We conducted a test of the usefulness of behavioral methods to control occupational health problems by reducing workers' exposures to toxic chemicals. Four plastics workers were trained in nine behaviors selected for potential to reduce their exposures to styrene, a common chemical with multiple toxic effects. Behavioral measures indicated that the workers quickly came to emit most of the behaviors. Measures of air samples indicated that large decreases in exposures to styrene accompanied the changes in behaviors for the three workers who had been selected because they most needed relief from their exposures and because they had opportunities to control their exposures by the ways they behaved.

Behavior Therapy↗
PubMed1977

Evaluating interobserver reliability of interval data.

Previous recommendations to employ occurrence, nonoccurrence, and overall estimates of interobserver reliability for interval data are reviewed. A rationale for comparing obtained reliability to reliability that would result from a random-chance model is explained. Formulae and graphic functions are presented to allow for the determination of chance agreement for each of the three indices, given any obtained per cent of intervals in which a response is recorded to occur. All indices are interpretable throughout the range of possible obtained values for the per cent of intervals in which a response is recorded. The level of chance agreement simply changes with changing values. Statistical procedures that could be used to determine whether obtained reliability is significantly superior to chance reliability are reviewed. These procedures are rejected because they yield significance levels that are partly a function of sample sizes and because there are no general rules to govern acceptable significance levels depending on the sizes of samples employed.

Journal Article↗
PubMed1976

Safe and unsafe behavior and its modification.

After discussing some of the limitations of existing behavioral safety research, the authors propose a new approach to the problem. The approach is based on systematically controlling the psychological environment by precisely defining and rewarding safe behabiors and extinguishing unsafe behaviors. This approach to changing behavior is broadly designated the experimental analysis of behavior, and comprises two separate components, applied behavior analysis and applied behavior management. Application of the principles to the problem of increasing the frequency of safe behaviors and decreasing the frequency of unsafe behaviors is illustrated with two examples, one real, one hypothetical. A conclusion is drawn that researchers pursuing behavioral approaches to accident reduction should utilize the methods and technology of applied behavior analysis and management.

Accident Prevention↗
PubMed1973

The effects of contingent music on the intensity of noise in junior high home economics classes.

The effects of quiet-contingent music on the general noise levels of four seventh- and eighth-grade classrooms were investigated. Following a baseline procedure, popular radio music was used to reinforce maintenance of noise below an acceptable level of intensity, 70 decibels, in three of the four classes. In the fourth class, a reversal design was used to show that the contingent presentation of the radio music was important to control the noise produced by the students. The teacher was free to engage in instructional activities because data collection and presentation of music were controlled by automatic apparatus.

Journal Article↗
PubMed1973

The modification of sentence structure and its relationship to subjective judgements of creativity in writing.

The present study objectively defined and manipulated some compositional variables in 10-sentence stories written by fourth-, fifth-, and sixth-grade students, and related these operationally defined variables to subjective judgements of creativity. Points, exchangeable for candy and extra recess, were given to members of two teams contingent upon their using different adjectives, different action verbs, and different sentence beginnings. The students' use of these selected parts of speech was modified and the independent subjective ratings indicated that stories written during contingency conditions were generally rated as more creative than those written during baseline conditions. Operational definitions that specify non-repetition or variety of responses, and contingencies that require response diversity may provide a beginning basis for defining writing creativity and the conditions that maximize its occurrence.

Journal Article↗
PubMed1973

Effects of bonuses for punctuality on the tardiness of industrial workers.

This study evaluated the effectiveness of an incentive procedure designed to increase the punctuality of six workers who were chronically late to work in a manufacturing company. The six workers in the experiment received a 2.00 pesos ($0.16 U.S.) bonus for every day that they arrived on time. A reversal design was used. The contingent bonuses increased the workers' rates of punctuality compared to their baseline rates. A control group of six workers observed during the same 77-week period showed a trend toward decreasing punctuality. These results suggest that the use of small daily bonuses is a practical procedure for modifying chronic tardiness among industrial workers.

Journal Article↗