PHASE-SHIFTING EFFECTS OF DUSKLIKE AND DAWNLIKE LIGHT PULSES ON THE CIRCADIAN ACTIVITY RHYTHMS OF SYRIAN HAMSTERS
Bibliographic record
Abstract
This study tested whether light pulses with a dusklike offset or a dawnlike onset caused phase shifts of different sizes in the circadian wheel-running activity of Syrian hamsters, Mesocricetus auratus. Six experiments were conducted, each with 30 hamsters; the hamsters received first one type of pulse and then the other type a few weeks later, allowing a paired comparison. The six experiments represented the combination of two maximum light intensities (150 and 250 lux) and three zeitgeber times (ZTs) at which the pulses were given (ZT13.5, ZT14.5, and ZT20). Pulses were 30 minutes long, a relatively short duration to minimize circadian time effects. Aschoff's type II method of measuring phase shifts was used. In none of the six experiments did a two-tailed paired t test detect a significant difference in the size of phase shifts caused by dusklike versus dawnlike pulses. A three-way analysis of variance (ANOVA) on the combined data from all six experiments (with pulse type, pulse intensity, and ZT as factors) also failed to detect a significant effect of pulse type. Statistical power was calculated and found to be reasonably good. These negative results are in line with those of a previous study in which a different methodology was used.
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How this classification was reachedexpand
Full frame distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.001 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.000 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one teacher head, not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".