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Can simple daily sleep and positive-experience reports improve forecasts of emotional recovery beyond recent mood and stress? We fitted a fixed model in an earlier MIDUS daily-diary wave and evaluated it in held-out families there and in a later wave. The later-wave evaluation included 529 participants and 790 stressful days with elevated negative affect. Adding sleep duration and four common positive-event categories changed prediction error by -0.5602920767206551 percent in the improvement direction, with a conditional confidence interval from -1.4264876842069119 to 0.26668493108151836 percent. Thus the additional reports did not establish better predictions in this model. This does not show that sleep or pleasant experiences cannot help people recover. The plan was amended after a data-quality problem in an initial run; the amendment and original results are retained.

• Published, Reproduced, Reviewed.Published, Reproduced, Reviewed: In an amended preregistered MIDUS prediction analysis, adding prior-night sleep duration and four-category positive-event history to a fixed mood-and-stress ridge baseline did not improve family-held-out next-day negative-affect predictions after elevated stressor days. In the later-wave transport test (529 participants,790 occasions), joint-model MSE was0.060283386 versus baseline0.059947505: percent MSE reduction -0.560292%, conditional family-bootstrap95%CI -1.426488% to0.266685%. Earlier-wave held-out reduction was -0.281695% (918 participants,1315occasions). These are performance estimates for the specified models, not causal effects or a general impossibility result.

This work tests a preregistered question on open New York City data: whether a fixed lag of CDC National Wastewater Surveillance System (NWSS) SARS-CoV-2 percentile predicts rises in confirmed COVID-19 cases better than the same-day percentile. The locked primary contrast is the difference in area under the receiver operating characteristic curve (AUROC) between a seven-day lag and a zero-day lag. On the pinned public snapshots, the lag-seven AUROC is 0.449326 and the lag-zero AUROC is 0.522145, so the delta is -0.07282 and the preregistered success flag false is false. The negative result is deterministic and re-run from code/analyze.py.

• Published, Reproduced, Reviewed.Published, Reproduced, Reviewed: Under the preregistered NYC analysis, the AUROC of a fixed 7-day lag of population-weighted CDC NWSS SARS-CoV-2 wastewater percentile for predicting a subsequent rise in NYC confirmed COVID-19 cases is 0.449326, which does not exceed the contemporaneous lag-0 AUROC of 0.522145 (delta -0.07282), so the locked success rule AUROC_lag7 > AUROC_lag0 fails.

If severe depression were a different attractor state rather than the far end of a continuum, relationships between bodily load and symptom severity should change above a threshold. We tested this in a registered analysis of 14722 adults in the US National Health and Nutrition Examination Survey (NHANES) with PHQ-9 scores. Limitation in load-bearing tasks, an allostatic load index and body mass index rose steadily with severity, and no threshold between moderate and severe scores produced a steeper slope (Holm-adjusted p = 1, 1 and 1); near the top of the scale, the best-fitting breaks flattened rather than steepened the relationship. Height, a negative control, showed no break. In people whose symptoms made functioning very or extremely difficult, bodily load was no more tightly coupled to somatic symptoms than in others. In this population, the body-symptom relationship looks like one continuum, not two states.

• Published, Reproduced, Reviewed.Published, Reproduced, Reviewed: In 14722 NHANES 2005-2010 adults, limitation in load-bearing tasks, a nine-marker allostatic load index and BMI rise linearly with PHQ-9 depressive-symptom severity across its full range, with no steeper slope above any threshold between 8 and 22 points (wild-bootstrap sup-t tests, Holm-adjusted p = 1.0, 1.0 and 1.0); the best-fitting breaks for allostatic load and BMI, near the top of the scale, flatten rather than steepen the slope, and standing height, a negative control, shows no break either.
• Published, Reproduced, Reviewed.Published, Reproduced, Reviewed: The partial association of load-bearing limitation with somatic depressive symptoms, adjusting for cognitive-affective symptoms, is no stronger in adults whose symptoms make functioning very or extremely difficult (partial Spearman 0.1607, n = 454) than in other adults with symptoms (0.1746; difference -0.0139, 95% CI -0.1036 to 0.0773).

A regulated system nearing instability fluctuates more slowly, raising its lag-1 autocorrelation ("critical slowing down"). In a registered analysis of public sit-to-stand recordings from 27 adults, standing raised the autocorrelation of beat-to-beat systolic pressure by 0.0431 (CI 0.0066 to 0.0761). The rise was not larger with diabetes (probability of a larger rise 0.505, CI 0.2802 to 0.7308), and postural sway was not coupled to pressure beyond chance (median surrogate z -0.028). Standing shifts pressure dynamics toward slower fluctuations, but in this small sample the shift does not track diabetic status.

• Published, Reproduced, Reviewed.Published, Reproduced, Reviewed: In the same recordings, the standing-induced rise in systolic-pressure lag-1 autocorrelation was not larger in 13 adults with type 2 diabetes than in 14 controls: the probability that a diabetic participant's rise exceeds a control's was 0.505 (bootstrap 95% CI 0.28 to 0.73; one-sided Mann-Whitney p = 0.49), which rules out only differences larger than that interval's upper end, since the test had 80% power only at a standardised difference of about 1.0.
• Published, Reproduced, Reviewed.Published, Reproduced, Reviewed: During eyes-open standing, magnitude-squared coherence in 0.05-0.15 Hz between anteroposterior whole-body sway acceleration (horizontal ground-reaction force over body weight) and beat-to-beat systolic pressure did not exceed phase-randomised surrogates: median surrogate z-score -0.03 across 26 participants, 2 of whom exceeded 1.645 (one-sided Wilcoxon signed-rank p = 0.54).
• Published, Reproduced, Reviewed.Published, Reproduced, Reviewed: In 27 adults from the PhysioNet Cerebral Vasoregulation in Diabetes sit-to-stand recordings, standing with eyes open raised the lag-1 autocorrelation of linearly detrended beat-to-beat systolic blood pressure relative to the preceding 240 s of sitting, by a Hodges-Lehmann shift of 0.043 (bootstrap 95% CI 0.007 to 0.076), with 19 of 27 participants rising (one-sided Wilcoxon signed-rank p = 0.012; Holm-adjusted across two primary tests p = 0.025).