Describes an experiment that provides a study of the different colors and shapes of crystals of transition metal dimethylglyoxime complexes with the use of a low power microscope. Discusses the preparation and examination of the crystals. (CW)

Infants become selectively sensitive to phonological distinctions relevant to their native language at an early age. One might expect that infants bring some of this phonological knowledge to bear in encoding the words they subsequently acquire. In line with this expectation, studies have found that 14-month-olds are sensitive to mispronunciations…

Two eye movement experiments examined effects on syntactic reanalysis when the correct analysis was briefly entertained at an earlier point in the sentence. In Experiment 1, participants read sentences containing a noun phrase coordination/clausal coordination ambiguity, while in Experiment 2 they read sentences containing a subordinate clause…

Bacteriocins, bacteriocidal proteins produced by bacteria, have a very restricted killing range. In this exercise each student isolates an environmental "Enterococcus spp." culture using selective media and then evaluates it for bacteriocin activity against "Enterococcus" strains isolated by classmates.

Items commonly belong to many categories. Cross-classification is the classification of a single item into more than one category. This research explored 2- to 6-year-old children's use of 2 different category systems for cross-classification: script (e.g., school-time items, birthday party items) and taxonomic (e.g., animals, clothes). The…

The model-based view (MBV) of science education, which strives for authenticity in science teaching, is currently seeking support from the philosophical positions related to the Semantic View of Theories (SVT). These recent advances are promising steps towards establishing a robust philosophical framework, but they need revision in so far as they…

We present an experimental method to obtain the effective mass of an unloaded oscillating spring. We measure the period "T"("n") of the partial springs that result when hanging "n" of the total "N" coils of a given spring. Data are correlated with the expectation of a simple model for "T"("n") that takes into account the effective mass of the…

In the 1930s physicists were confronted by two conflicting values for the charge of the electron as measured with great precision by two different methods. Could it be that there are two kinds of (negative) electrons, differing in charge by a fraction of a percent? The experiments were reconciled when a small systematic error in one of the…

Once an intriguing topological novelty known only to mathematicians, the Mobius strip has become a source of fascination and inspiration to the layperson and artist alike. Principal among its features are the two strange properties that the Mobius strip is a surface with only one side and one edge. A Mobius strip is readily formed by taking a long…

When viewing an event in which an object moves behind an occluder on part of its trajectory, 4-month-old infants perceive the trajectory as continuous only when time or distance out of sight is short. Little is known, however, about the conditions under which young infants perceive trajectories to be discontinuous. In the present studies we focus…

In reading, fixation durations are longer when the eyes fall near the center of words than when fixation occurs toward the words' ends-the inverted-optimal viewing position (I-OVP) effect. This study assessed whether the I-OVP effect was based on the fixation position in the word or the fixation position in the visual stimulus. In Experiments 1-3,…

This article reports that a quiet debate is unfolding over proposals to tinker with No Child Left Behind Act's (NCLB) definition of what constitutes "scientifically based research" in education while other ideas for revamping it are taking center stage. Sprinkled through the federal education statute more than 100 times, the references…

A phase-shift interferometry experiment is proposed, working on a Twyman-Green optical configuration with additional polarization components. A guideline is provided to modern phase-shift interferometry, using concepts and laboratory equipment at the level of undergraduate optics courses. (Contains 5 figures.)

Results of two experiments show children's understanding of diversity in personal preference is incomplete. Despite acknowledging diversity, in Experiment 1 (N = 108), six- and eight-year-old children were less likely than adults to see preference as a legitimate basis for personal tastes and more likely to say a single truth could be found about…

The refraction of a light ray by a homogeneous, isotropic and non-dispersive transparent material half-space in uniform rectilinear motion is investigated theoretically. The approach is an amalgamation of the original Fermat's principle and the fact that an isotropic optical medium at rest becomes optically anisotropic in a frame where the medium…