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Biomedical subjects

B Randolph

Publications and source records attributed to B Randolph.

7 recordsLinked to original sources
PubMed2000

Age differences in visual search for compound patterns: long- versus short-range grouping.

Visual search for compound patterns was examined in observers aged 6, 8, 10, and 22 years. The main question was whether age-related improvement in search rate (response time slope over number of items) was different for patterns defined by short- versus long-range spatial relations. Perceptual access to each type of relation was varied by using elements of same contrast (easy to access) or mixed contrast (hard to access). The results showed large improvements with age in search rate for long-range targets; search rate for short-range targets was fairly constant across age. This pattern held regardless of whether perceptual access to a target was easy or hard, supporting the hypothesis that different processes are involved in perceptual grouping at these two levels. The results also point to important links between ontogenic and microgenic change in perception (H. Werner, 1948, 1957).

Adult↗
PubMed1995

Check-off logs for routine equipment maintenance.

The regulatory requirement for appropriate routine instrument maintenance documentation is approached by laboratories in numerous ways. Standard operating procedures (SOPs) may refer to maintenance listed in instrument manuals, may indicate "periodic" performance of an action, or may indicate specific tasks to be performed at certain frequencies. The Quality Assurance Unit (QAU) task of assuring the performance of these indicated maintenance tasks can be extremely laborious if these records are merged with other analysis records. Further, the lack of written maintenance schedules often leads to omission of infrequently performed tasks. We recommend creation of routine maintenance check-off logs for instruments with tasks grouped by frequency of expected performance. Usage of such logs should result in better laboratory compliance with SOPs and the compliance can be readily monitored by QAU or by regulatory agencies.

Documentation↗
PubMed1989

Patients' and physicians' assessments of patients' health in rural Mississippi.

A two-week health-appraisal survey of the patients of a rural Mississippi medical clinic during the month of January 1988 revealed that the larger percentage of the patients assessed their individual health status in about the same way that it was assessed by the clinic's staff physicians. The highest dissimilarity between physicians' and patients' assessments of patients' health occurred for the black patients in general and for the black men specifically. Findings of this study indicate a need for increased efforts in health education for rural communities, more research on how rural people assess their own health, and greater knowledge of rural people's health belief models.

Adolescent↗
PubMed1984

Bacteriophage T4 bypass31 mutations that make gene 31 nonessential for bacteriophage T4 replication: isolation and characterization.

T4 bacteriophage mutants called bypass31 (byp31) that specifically suppress gene 31 amber mutations have been isolated and characterized. The mechanism by which the byp31 mutation, byp31-1, suppresses gene 31 nonsense mutations does not involve synthesis of gp31 or of a particular gp31 fragment; furthermore, the byp31 allele suppresses all nonsense mutations in gene 31 that have been tested. We detect no unusual properties among the T4 particles made in su- cells by the T4amN54byp31-1 double mutant. These virions, made in the absence of gp31, show normal heat sensitivity, normal sensitivity to osmotic shock, and normal morphology. Specific different gene 31 missense mutants are able to form plaques with high efficiencies on the following two types of host defective cells: (i) Escherichia coli groEL (Tilly et al., Proc. Natl. Acad. Sci. U.S.A. 78:1629-1633, 1981) mutants that block T4 capsid assembly and (ii) E. coli rho mutants in which T4+ heads are assembled, but in which tail production and DNA synthesis are blocked. (Note that not all rho mutants block T4 production [G. Binkowski and L. D. Simon, p. 342-350, in C. K. Mathews, E. M. Kutter, G. Mosig, and P. B. Berget, ed., Bacteriophage T4, 1983]; T4 is able to replicate in rho mutants such as rho ts15, whose principal defect is that they fail to terminate transcription.) The byp31-1 allele permits production of T4 particles in E. coli groEL host-defective mutants, but not in E. coli rho host mutants.

DNA Replication↗
PubMed1983

Stabilization of proteins by a bacteriophage T4 gene cloned in Escherichia coli.

The cloned bacteriophage T4 pin gene functions to stabilize several different kinds of proteins in Escherichia coli bacteria. Incomplete proteins such as puromycyl polypeptides, abnormal but complete proteins such as the lambda phage tsO protein, and labile eukaryotic proteins encoded by genes cloned in E. coli such as mature human fibroblast interferon are stabilized in cells in which the T4 pin gene is expressed. The cloned T4 pin gene does not seem to affect the turnover of normal E. coli proteins.

Bacterial Proteins↗