Residual Force Enhancement Is Preserved for Conditions of Reduced Contractile Force
Bibliographic record
Abstract
INTRODUCTION: The isometric muscle force attained after active stretch is greater than that attained in a purely isometric contraction. This property is referred to as residual force enhancement (RFE). Because RFE is thought to be caused by a titin-based passive force, it should be preserved in reduced contractile force states. Therefore, we evaluated the magnitude of RFE in normal and reduced contractile force states. METHODS: Skinned fibers of rabbit psoas and soleus (N = 60) were used in all experiments. Reduced contractile force states were induced (i) by using a low Ca concentration (N = 30), (ii) by adding 20 mM butanedione monoxime (N = 15), and (iii) by lowering the pH level (N = 15). Force enhancement and reference isometric tests were conducted for each condition. In the force enhancement tests, fibers were actively stretched from an average sarcomere length of 2.4 to 3.0 μm. The isometric force attained 15 s after the end of stretching was used for analysis. In the isometric reference tests, fibers were activated isometrically at an average sarcomere length of 3.0 μm, and the force at steady state was used for analysis. The absolute and relative magnitudes of RFE were calculated. RESULTS: The absolute RFE was the same for the normal and reduced contractile force states. Because the isometric reference force was smaller in the reduced contractile force states, the relative RFE was greater in the reduced contractile force than the normal states for all conditions. CONCLUSION: RFE was preserved in the reduced contractile force states.
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 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 | 0.001 | 0.001 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.001 | 0.000 |
| Bibliometrics | 0.000 | 0.001 |
| Science and technology studies | 0.000 | 0.002 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.002 | 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".