The filtration efficiency of ventilation air cleaners is highly particle‐size dependent over the 0.01 to 3 μm diameter size range. Current standardized test methods, which determine only overall efficiencies for ambient aerosol or other test aerosols, provide data of limited utility. Because particles in this range are respirable and can remain airborne for prolonged time periods, measurement of air cleaner fractional efficiency is required for application to indoor air quality issues. The objectives of this work have been to 1) develop a test apparatus and procedure to quantify the fractional filtration efficiency of air cleaners over the 0.01 to 3 μm diameter size range and 2) quantify the fractional efficiency of several induct air cleaners typical of those used in residential and office ventilation systems. Results show that efficiency is highly dependent on particle size, flow rate, and dust load present on the air cleaner. A minimum in efficiency was often observed in the 0.1 to 0.5 μm diameter size range. The presence of a dust load frequently increased an air cleaner's efficiency; however, some air cleaners showed little change or a decrease in efficiency with dust loading. The common furnace filter had fractional efficiency values of less than 10% over much of the measurement size range.

No abstract

This exploratory study was designed to investigate the relationship between specific classroom behaviors and critical thinking. Four indicants of student involvement were measured using a modified version of Flanders's Interaction Analysis system: student participation, peer-to-peer interaction, faculty questions, and faculty encouragement and use of student ideas. Critical thinking was assessed by use of the Watson-Glaser Critical Thinking Appraisal and the Chickering behavioral self-report index. Twelve college classrooms, equally divided among disciplines, were studied using canonical correlations, analysis of variance, and univariate analyses. Student participation, encouragement, and peer-to-peer interaction consistently emerged as being significantly and positively related to critical thinking. The results, though more suggestive than definitive, have significant implications for future research methodology and for faculty development efforts.

No abstract

Today, most agree that the health care system in the United States is in need of reform and that existing health disparities have huge implications for both that system and society as a whole. As a result, academic medicine has come to play a central role in addressing health disparities in a pluralistic society. Today, diversity is no longer a projection; it is a reality. Yet, most diversity efforts continue to run parallel to core institutional processes, rather than as part of the mission of the institution. Researchers agree that, to promote a healthy and vital society, leaders in academic medicine must create institutions that can serve diverse populations. To do so, they must first increase their institutional capacity for diversity. This article outlines the next generation of work on diversity and inclusion, drawing on a broad body of research and practice to identify some of the key elements for building the kind of institutional capacity necessary for sustained change in academic medicine, including a deeper engagement of mission, one that considers diversity as core to excellence; an inclusive and differentiated understanding of diversity institutionally; alignment and intentionality with respect to key institutional elements; key metrics associated with success and a serious process to monitor progress; and the identification of diverse talent for leadership at all levels.