In order to determine whether the human pattern of circulating melatonin resembles that previously described in lower animals, men 19-32 years old were exposed to a light-dark cycle with 14 hours of light per day (L:D 14:10). In whites and blacks, nocturnal (dark phase, sleeping) melatonin levels were almost always elevated to 0.05-0.1 ng/ml plasma compared with lower or undetectable levels during the day, measured by the tadpole bioassay. Thin-layer migration of bioactive material was identical to that for melatonin standard. A rhythm with nocturnal elevation of urinary 5-hydroxyindoleacetic acid (5-HIAA) was observed. Nocturnal (sleep phase) rise in blood melatonin (but not urinary 5-HIAA) continued during 21/2 day-night cycle lengths after the onset of constant light. Though the dark phase plasma melatonin rise was less marked after reversal of the sleep-wake cycle (no change in the light cycle), dark phase rise in urinary 5-HIAA continued. Though marked cardiovascular and other effects were produced by intravenous isoproterenol or scopolamine, no definite effect on melatonin levels was observed after either drug during the light phase in waking subjects.

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This study was undertaken to develop guidelines for making interpretive inferences from scores on the Test of English for International Communication (TOEIC), a norm‐referenced test of English‐language listening comprehension (LC) and reading (R) skills, about level of ability to use English in face‐to‐face conversation, indexed by performance in the Language Proficiency Interview (LPI) situation. LPI performance, rated according to behaviorally defined levels on the LPI/ILR/FSI quasi‐absolute proficiency scale, was treated as a context‐independent criterion, using the familiar regression model in an apparently novel application (for such criterion‐referencing purposes) in the context of a large‐scale ESL‐testing program. The study employed TOEIC/LPI data‐sets generated during operational ESL assessments in representative TOEIC‐use settings (places of work or work‐related ESL training) in Japan, France, Mexico, and Saudia Arabia, involving samples of adult, educated ESL users/learners in or preparing for ESL‐essential positions with companies engaged in international commerce. The pattern of TOEIC/LPI concurrent correlations was consistent across samples and there was relatively close fit between sample LPI means and estimates from TOEIC scores, especially TOEIC‐LC, using combined‐sample regression equations. Theoretical and pragmatic implications of the findings are discussed. General guidelines are provided for making inferences about LPI‐assessed level of oral English proficiency from TOEIC scores. Directions are suggested for further research and development activities in the TOEIC testing context.

The criterion most frequently used in studies designed to assess the predictive validity of measures used in college admission has been the freshman‐year GPA. It is not self‐evident that the first‐year GPA provides either a sufficient or a representative sample of a student's academic performance. Questions have been raised regarding the validity of admissions measures for predicting longer‐term performance in college. This is the report of a systematic review of research bearing on (a) the validity of admissions measures for predicting GPA that reflects performance beyond the freshman year—i.e., longer‐term cumulative or independently computed post‐freshman‐year GPA, such as senior‐year GPA; (b) the comparative relevance and utility of freshman‐year, cumulative, and independently computed post‐freshman‐year GPA as criteria for the validation of admissions measures. Among other things, the research reviewed lends support to the traditional practice of employing the freshman‐year GPA in admissions‐related predictive validity studies.