Describes a method for identifying and examining single ice crystals by photographing a thin sheet of ice placed between two inexpensive polarizing filters. Suggests various natural and prepared sources for ice that promote students' insight into crystal structures, and yield colorful optical displays. Includes directions, precautions, and sample…

Two studies investigated interrater agreement among 10 clinical dental examiners who scored residual subgingival calculus after student scaling on 4,160 real and 92 manikin tooth surfaces. Interrater reliability was low. Results suggest a need in periodontics for effective examiner calibration methods and objective subgingival calculus detection…

A portable and inexpensive blowfly trap, constructed from flower pots/buckets and mesh, suitable for introductory studies in blowfly succession is described. Investigations that examine species composition over time and the differences between baits are discussed. (KR)

Two surveys investigated the extent of photography instruction in dental schools. The first survey of 53 schools revealed that 36% had formal dental photography programs. Of 21 photography instructors surveyed in the second study, 67% had no formal training, many knew little about texts or resources, and techniques and knowledge varied. (MSE)

A technique for the numerical identification of bacteria using normalized likelihoods calculated from a probabilistic database is described, and the principles of the technique are explained. The listing of the computer program is included. Specimen results from the program, and examples of how they should be interpreted, are given. (KR)

This article takes a critical look at practical work in school science and the often extravagant claims that are made for it. A case is made for a more rigorous, theory-driven approach to practical methods. (Author/CW)

Described is an interdisciplinary unit on pseudoscience which combines interest in unidentified flying objects (UFO's), physics, astronomy, art, and english composition. The different phases of the lesson, assignments, and evaluation are discussed. A list of books available on UFOs is provided. (CW)

A simple experimental arrangement that makes it possible to simultaneously observe and compare on a screen the two interference patterns produced by reflected and transmitted light from incident white light impinging on a soap film directly is described. Procedures and illustrated effects are discussed. (CW)

Two experiments which can be used to illustrate light diffraction using compact disks are detailed. Included are procedures, computations, and probable results. (CW)

Describes science experiments for undergraduate biology instruction on the concepts of mutation and characterization of the resulting mutant strains. The filamentous fungi "Fusarium moniliforme" is used to illustrate the induction of mutants (mutagenesis), identification of the mutated gene, construction of a biochemical pathway, and…

Presents a singular alternative to the Indole Methyl-red Voges-Proskauer Citrate (IMViC) test that uses bile-esculin agar to distinguish between the Escherichia coli and Enterobacter aerogenes bacteria. Includes materials and methods, results, and conclusions for the test. (MDH)

Shows how fruit flies can be used in the teaching genetics laboratory to correlate the principles of heredity with the modern understanding of enzymes. (Contains 16 references.) (MDH)

Describes a novel course in first-year undergraduate practical biology that introduces students to the principles and practices of a variety of biological techniques. (CCM)

Presents a series of experiments that can be used to demonstrate how aspirin can be synthesized and characterized, how the hydrolysis of aspirin can be used as an introduction to kinetics, and how coordination chemistry (chelation) can be introduced by preparing and characterizing the copper complexes of aspirin and salicylic acid. (Contains over…

Presents instructions for carrying out polymerase chain reactions with a bit of inexpensive equipment. (WRM)