Everyone enjoys seeing the cloudy white fog generated when solid carbon dioxide (dry ice) is placed in water. Have you ever wondered what physical and chemical processes occur to produce this fog? When asked this question, many chemical educators suggest that the fog is produced when atmospheric water vapor condenses on cold carbon dioxide gas…

In today's competitive global economy characterized by knowledge acquisition, the concept of knowledge management has become increasingly prevalent in academic and business practices. Knowledge creation is an important factor and remains a source of competitive advantage over knowledge management. Constructivism holds that learners learn actively…

Congruency effects were examined using a manual response version of the Stroop task in which the relationship between the colour word and its hue on incongruent trials was either kept constant or varied randomly across different pairings within the stimulus set. Congruency effects were increased in the condition where the incongruent hue-word…

The molecular basis of evolution is an important and challenging concept for students to understand. In a previous article, we provided some of the scientific background necessary to teach this topic. This article features a series of laboratory activities demonstrating that molecular events can alter the genomes of organisms. These activities are…

The main result of an experiment is typically an estimate of the average treatment effect (ATE) and its standard error. In most experiments, the number of covariates that may be moderators is large. One way this issue is typically skirted is by interpreting the ATE as the average effect for "some" population. Cornfield and Tukey (1956)…

An experiment is described in this test that was designed to study the role of the cyclin B protein in a cell-free system. The work was performed in the lab of Tim Hunt who, together with Hartwell and Nurse, received the Nobel Prize in Physiology or Medicine in 2001 "for their discoveries of key chemicals that regulate the cell division cycle." It…

Signals during delays to reinforcement may lessen reductions in responding that typically occur when there is a delay between a response and its reinforcer. Sparse applied research has been devoted to understanding the conditions under which responding may be maintained when delays to reinforcement are introduced. We evaluated the extent to which…

Purpose: In this series of articles--"Research Ethics I", "Research Ethics II", and "Research Ethics III"--the authors provide a comprehensive review of the 9 core domains for the responsible conduct of research (RCR) as articulated by the Office of Research Integrity. In "Research Ethics I", they present a historical overview of the evolution of…

Purpose: This work provides a quantitative assessment of the positional tracking accuracy of the NDI Wave Speech Research System. Method: Three experiments were completed: (a) static rigid-body tracking across different locations in the electromagnetic field volume, (b) dynamic rigid-body tracking across different locations within the…

The present research examined whether 3-month-old infants, the youngest found so far to engage in goal-related reasoning about human agents, would also act as if they attribute goals to a novel non-human agent, a self-propelled box. In two experiments, the infants seemed to have interpreted the box's actions as goal-directed after seeing the box…

Gradient scouting is the best way to decide the most suitable elution mode in reversed-phase high-performance liquid chromatography (RP-HPLC). A simple rule for this decision involves the evaluation of the ratio [delta]t/t[subscript G] (where [delta]t is the difference in the retention time between the last and the first peak and t[subscript G] is…

In order to meet changing curricular and societal needs, a three-phase system and synchronous motor laboratory experience for sophomore-level students in a wide variety of engineering majors was designed, implemented, and assessed. The experiment is unusual in its early placement in the curriculum, and in that it focuses primarily on basic…

Systematic errors can cause measurements to deviate from the actual value of the quantity being measured. Faulty equipment (such as a meterstick that is not marked correctly), inaccurate calibration of measuring devices (such as a scale to measure mass that has not been properly zeroed), and improper use of equipment by the experimenter (such as…

Several principles of green chemistry are introduced through this experiment designed for use in the undergraduate analytical chemistry laboratory. An established experiment of liquid CO2 extraction of D-limonene has been adapted to include a quantitative analysis by gas chromatography. This facilitates drop-in incorporation of an exciting…

This article describes a case study involving an assistive device that aided a student with low vision registered in the introductory physics course at Trent University in the fall of 2009. His Snellen visual acuity fluctuated significantly, with an average acuity of about 20/400. This low acuity presented obvious difficulties for him with the…