Effect of lipid extraction on analyses of stable carbon and stable nitrogen isotopes in coastal organisms of the Aleutian archipelago
Bibliographic record
Abstract
We tested whether extracting lipids reduced confounding variation in δ 13 C and δ 15 N values by analyzing paired lipid-extracted (LE) and non-lipid-extracted (NLE) samples of bald eagle ( Haliaeetus leucocephalus (L., 1766)) whole eggs, muscle tissue from nine seabird and one terrestrial bird species, muscle tissue from four marine fish species, and blue mussels ( Mytilus edulis L., 1758) collected from the Aleutian archipelago, Alaska. Lipid extraction significantly increased δ 13 C by an average of 2.0‰ in whole eggs, 0.8‰ in avian muscle, 0.2‰ in fish muscle, and 0.6‰ in blue mussels. Lower δ 13 C values in NLE samples covaried positively with lipid content across all sample types. Lower δ 13 C values in NLE samples were not correlated with lipid content within bald eagle eggs and blue mussels, but covaried positively with percent lipid in avian and fish muscles. Neither lipid extraction nor percent lipid significantly changed δ 15 N values for any sample type. Lower δ 13 C values in most NLE avian and fish muscle tissues should not confound interpretation of pelagic versus nearshore sources of primary production, but lipid extraction may be necessary when highly precise estimates of δ 13 C are needed. Lipid extraction may not be necessary when only δ 15 N is of interest.
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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 | 0.001 | 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 | 0.000 |
| 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".