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A global increase in offshore windfarm development is critical to our renewable energy future. Yet, widespread construction plans have generated substantial concern for impacts to co-occurring organisms and the communities they form. Pile driving construction, prominent in offshore windfarm development, produces among the highest amplitude sounds in the ocean creating widespread concern for a diverse array of taxa. However, studies addressing ecologically key species are generally lacking and most research is disparate, failing to integrate across response types (e.g., behavior, physiology, and ecological interactions), particularly in situ. The lack of integrative field studies presents major challenges to understand or mitigate actual impacts of offshore wind development. Here, we examined critical behavioral, physiological, and antipredator impacts of actual pile driving construction on the giant sea scallop (Placopecten magellanicus). Benthic taxa including bivalves are of particular concern because they are sound-sensitive, cannot move appreciable distances away from the stressor, and support livelihoods as one of the world's most economically and socially important fisheries. Overall, pile driving sound impacted scallops across a series of behavioral and physiological assays. Sound-exposed scallops consistently reduced their valve opening (22%), resulting in lowered mantle water oxygen levels available to the gills. Repeated and rapid valve adductions led to a 56% increase in metabolic rates relative to pre-exposure baselines. Consequently, in response to predator stimuli, sound-exposed scallops displayed a suite of significantly weaker antipredator behaviors including fewer swimming events and shorter time-to-exhaustion. These results show aquatic construction activities can induce metabolic and ecologically relevant changes in a key benthic animal. As offshore windfarm construction accelerates globally, our field-based study highlights that spatial overlap with benthic taxa may cause substantial metabolic changes, alter important fisheries resources, and ultimately could lead to increased predation., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

The passive exhalation flow-volume plots of preterm lambs exhibit curvature. To explain this curvature, we proposed two mathematical models that could predict the measured passive exhalation flow-volume data well. One model takes into account the flow and volume dependence of resistance and compliance. The second model emphasizes the time dependence of lung mechanics and considers the respiratory system viscoelastic properties and the analogy of the lung to two electronic resistor-capacitor circuits connected in parallel. We attempted to determine which of the two models is more valid by analyzing passive exhalation flow-volume data that were obtained while briefly obstructing flow midway through deflation. In 14 preterm lambs (130 d gestation), the flow of exhaled gas increased from 76 +/- 35 mL/s when measured just before obstruction to 90 +/- 30 mL/s when measured immediately after release of the obstruction (p less than 0.0001). This finding suggests that a time-dependent phenomenon was taking place during obstruction and is inconsistent with the model based upon the flow and volume dependence of resistance and compliance. We made similar measurements in four near-term (143-146 d gestation) and four full-term lambs (9-12 d of age). Their flow-volume curves were relatively linear, and they showed no increases in flow after removal of the obstruction. The results of this study strongly suggest that time-dependent phenomena caused the curvilinearity in the passive exhalation flow-volume plots of preterm lambs. We suspect that the time-dependent phenomena is associated with the premature lung and with parenchymal lung disease.(ABSTRACT TRUNCATED AT 250 WORDS)

This report calls attention to the Kleine-Levin Syndrome, a sleep disorder which predominantly occurs in adolescent males. It can easily be mistaken for other psychiatric or neurologic illness. Differential diagnosis and treatment are discussed.

Previous studies have shown large inhomogeneities in the distributions of ventilation and perfusion of newborn infants with hyaline membrane disease. The purpose of this study was to show that measurements of lung mechanics also show evidence of lung inhomogeneities and that a multiple compartment analysis of mechanics gives a more accurate representation of passive exhalation flow and volume than single valued mechanics. We studied 10 sedated preterm lambs (130 d gestation) weighing 2.2 +/- 0.3 kg at 4 h postnatal age. Passive exhalation lung mechanics of the respiratory system were measured by obstructing gas flow near end inhalation then, after pressures within the lung reached equilibrium, allowing the animals to exhale to the atmosphere. Airway pressure and flow signals were monitored by a computer then analyzed using single and multiple compartment analyses. Single compartment analysis of time constant (tau) in s, respiratory system resistance (R) in cm H2O/L/s and quasistatic compliance (C) in mL/cm H2O yielded tau = 0.16 +/- 0.07, R = 92 +/- 17, and C = 1.8 +/- 1.1 (mean +/- SD). Multiple compartment analysis yielded "fast compartment" tau 1 = 0.10 +/- 0.04, R1 = 90 +/- 28, and C1 = 1.1 +/- 0.5 and "slow compartment" tau 2 = 0.25 +/- 0.12, R2 = 503 +/- 288, and C2 = 0.7 +/- 0.6. All of the animals studied exhibited nonlinearity in their flow-volume plots. Calculated flow-volume plots were much more accurately portrayed by the two-compartment analysis than by single valued mechanics. Multiple compartment analysis of lung mechanics may provide useful insight into the pathophysiology of the preterm lab with hyaline membrane disease.