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Biomedical subjects

J L Middleton

Publications and source records attributed to J L Middleton.

3 recordsLinked to original sources
PubMed1991

A student-centered, problem-based surgery clerkship.

In the academic year 1989-90, the department of surgery at one college of medicine revised its third-year clerkship to focus on students' learning decision-making skills and critical thinking (cognitive skills) and acquiring knowledge about surgery. Learning to perform procedures and tasks (psychomotor skills) would be accomplished in the required fourth-year acting internships. Problem-based learning (PBL) was chosen as the clerkship's primary instructional method. Comprehensive student and program evaluation systems were established. The response by faculty and students has been very positive. Students believe that the new clerkship has helped them increase their abilities in resource use, time management, and retention of knowledge. Faculty have noted students' increased eagerness and enthusiasm for learning.

Clinical Clerkship↗
PubMed1975

Dichlorofluoromethane inactivates Saccharomyces cerevisiae.

Saccharomyces cerevisiae was incubated in aerosol cans containing YM broth and dichlorofluoromethane (f-21). The presence and number of viable cells were determined by inoculating (1% vol/vol) YM broth and by the plate count procedure (YM agar). Inactivation of the yeast was greater or more rapid when: (i) the thermodynamic activity (saturation value) of f-21 became greater through increasing the concentration of chemical from 0.5 to 1.5% (wt/wt) in a given volume (20, 40, or 80 ml) of broth, or by holding the concentration of chemical constant but increasing the volume of broth in the test vessel, (ii) the temperature of treatment was increased (7, 22, 37, and 47 C), (iii) samples with 1.5% (wt/wt) f-21 were agitated, (iv) young (8 h) rather than old (36 h or 10 days) cells were treated, and (v) cells were grown in YM broth without, rather than with, glucose. Adjusting the pH (6.3 to 4.0) of broth before treatment, pretreating the substrate with f-21, or distilling the chemical before use had no effect on viability of cells when treated with f-21. Yeast cells inactivated by f-21, chlorine, or heat were more resistant to disruption by sonic treatment than were viable cells.

Cell Survival↗