Abrupt Increase in UV Sensitivity at Late Log‐Phase of Growth in <i>Paramecium tetraurelia</i>
Bibliographic record
Abstract
In this study, changes in UV sensitivity, a parameter of the clonal aging that has been studied in the daily reisolation culture, were examined in the logarithmically growing Paramecium culture. Cells in logarithmically growing cultures are thought to change the internal states under rapidly changing external conditions. In contrast, cells in daily reisolation cultures gradually change the internal states, the process being called clonal development and aging, under the external conditions that are kept almost constant. Cells were sampled at regular intervals, irradiated with UV, and examined for UV sensitivity assessed by the clonal survival. We found that log-phase cells showed low sensitivity to UV until they reached 2,000-3,000 cells/ml, and beyond that cell density, abruptly became highly UV sensitive. The extent of this increase in UV sensitivity was similar to that between two age groups, 130 fissions of clonal age apart. When cells from a culture of 2,000-3,000 cells/ml were resuspended in culture medium at various cell densities, they changed to UV sensitive only when the cultures reached over approximately 2,600 cells/ml. These results suggest that paramecia become UV sensitive in response to change in the nutrient level when cell density exceeds 2,000-3,000 cells/ml.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.000 |
| 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 | 0.001 |
| Insufficient payload (model declined to judge) | 0.001 | 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 source (direct Gemma or distilled Codex), 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".