In continuation of our investigation into the buildup phenomenon appearing in gamma ray attenuation measurements in laboratory experiments we study the dependence of the buildup factor on the area of the absorber in an effort to reduce the buildup of photons. Detailed measurements are performed for up to two mean free paths of [superscript 60]Co…

The determination of the solid-liquid phase diagram of a binary system is always used as an experiment in the undergraduate physical chemistry laboratory courses. However, most phase diagrams investigated in the lab are simple eutectic ones, despite the fact that complex binary solid-liquid phase diagrams are more common. In this article, the…

Instrumentation for real-time PCR is used primarily for amplification and quantitation of nucleic acids. The capability to measure fluorescence while controlling temperature in multiple samples can also be applied to the analysis of proteins. Conformational stability and changes in stability due to ligand binding are easily assessed. Protein…

We present a lab that enables students to test the role of genes involved in the regulation of lateral roots growth in the model plant "Arabidopsis thaliana." Here, students design an experiment that follows the effects of the hormone auxin on the stimulation of genes involved in the formation of lateral root initials. These genes, known…

We have applied the heuristic-analytic theory of reasoning to interpret inconsistencies in student reasoning approaches to physics problems. This study was motivated by an emerging body of evidence that suggests that student conceptual and reasoning competence demonstrated on one task often fails to be exhibited on another. Indeed, even after…

This laboratory exercise presents a novel way to introduce undergraduate students to the specific detection of enzymatic activity by electrophoresis. First, students prepare a crude peroxidase extract and then analyze the homogenate via electrophoresis. Zymography, that is, a SDS-PAGE method to detect enzyme activity, is used to specifically…

Glow sticks are a popular Halloween staple familiar to most of our students. The production of light via a chemical reaction is called "chemiluminescence," and glow sticks are often used as demonstrations and experiments in the chemistry classroom to study reaction rates as a function of temperature. A black light can be used to…

In this article, Brian Coppola begins with the single key concept of Boyer, in "Scholarship Reconsidered." The statement appears as follows: "We believe the time has come to move beyond the tired old "teaching versus research" debate and give the familiar and honorable term "scholarship" a broader, more capacious…

We review literature on the teaching and learning of chemical kinetics at both the secondary and tertiary levels. Our aim in doing so is to summarize research literature, synthesize recommendations for future research, and suggest implications for practitioners. Two main bodies of literature emerged from the chemical kinetics education research:…

In this paper, we show data from the Colorado Learning Attitudes about Science Survey that suggests that Georgetown physics majors become increasingly expert in their attitudes towards physics learning and knowing after taking a course that combines two reformed curricula, Matter and Interactions (M&I) and Tutorials in Introductory Physics…

A meta-analysis of recent quantitative studies that examine the effects of cooperative learning (CL) on achievement outcomes in chemistry is presented. Findings from 25 chemical education studies involving 3985 participants (N[subscript treatment] = 1,845; N[subscript control] = 2,140) and published since 2001 show positive association between…

This paper advances a model describing how peer assessment supports self-assessment. Although prior research demonstrates that peer assessment promotes self-assessment, the connection between these two activities is underspecified. This model, the assessment cycle, draws from theories of self-assessment to elaborate how learning takes place…

Students frequently expressed difficulty in understanding the molecular mechanisms involved in chromosomal recombination. Therefore, we explored alternative methods for presenting the two concepts of the double-strand break model: Holliday junction and heteroduplex formation, and Holliday junction resolution. In addition to a lecture and…

Teaching assistants (TAs) that lead reformed recitations and labs must understand and buy into the design of the course and the research-based instructional strategies that the course requires in order to create high-fidelity implementations. We present a model that outlines possible influences on TAs' buy-in and their in-class actions coupled…

At the authors' public liberal arts institution, biology masters students are required to enroll in BIOL 5050: Teaching Techniques. Course topics include designing effective lectures, assessment, classroom management, diversity in the classroom, and active learning strategies. The impact of this type of training on graduate students' attitudes and…