Wetland Dynamics In A Terminal Lake Basin: Implications To Recent Hydroclimatic Evolution

Spatiotemporal surface water extent dynamics are important factors to understand the evolution of land surface and hydrologic processes in the Prairie Pothole Region (PPR). Surface water bodies such as lakes and wetlands are highly responsive to the variability in air temperature and precipitation, making them effective indicators of long-term hydrological conditions. Increased levels of precipitation influencing subsequent fill and spill processes have facilitated the wetland behavior in the Devils Lake Basin (DLB) as well as the rising lake levels that has caused $1 billon in flood damages. To date, the impacts of recent wetting (1993-present) on surface water area dynamics are inconclusive in various Northern Great Plains (NGP) watersheds. In this study, I utilize remotely sensed satellite imagery, field-based streamflow observations, PRISM precipitation data (the combination of remote sensing and numerical model), and numerically modeled open water evaporation to detect the influence of hydroclimatic drivers on surface water extent dynamics. Here, I delineated waterbodies utilizing a density slicing approach of the short-wave infrared band (SWIR) from Landsat imagery to identify the lake and wetland area changes to recent wetting in the DLB. Our results report six phases of dry and wet conditions experienced in the DLB over the study period from 1990-2017. Substantial total surface water expansion is detected in a pre-2011 period (2006-2011) increasing at 120 km2/year and then declining at 140 km2/year in a post-2011 (2011-2017) contraction of surface water extent. The pre-2011 changes are due to increased levels of precipitation and fill and spill processes after the 1999-2005 NGP drought. In contrast, the shrinkage of wetland areas during the post-2011 period is due to the hydroclimatic dominance of evaporation. During the post-2011 period, the responses of smaller wetlands (\u3c90,000 m2) are highly variable while the larger wetlands and lakes decline promptly due to evaporation. During the study period a hysteric loop of open water evaporation and surface water extent was also detected. With most of the global climate models predicting a continued progression of wetting conditions in the NGP, wetlands and open water area are also expected to increase. However, the findings show otherwise in the DLB where wetland areas are decreasing in the post-2011 period

Effect of angiotensin-converting enzyme inhibitor and angiotensin receptor blocker initiation on organ support-free days in patients hospitalized with COVID-19

IMPORTANCE Overactivation of the renin-angiotensin system (RAS) may contribute to poor clinical outcomes in patients with COVID-19. Objective To determine whether angiotensin-converting enzyme (ACE) inhibitor or angiotensin receptor blocker (ARB) initiation improves outcomes in patients hospitalized for COVID-19. DESIGN, SETTING, AND PARTICIPANTS In an ongoing, adaptive platform randomized clinical trial, 721 critically ill and 58 non–critically ill hospitalized adults were randomized to receive an RAS inhibitor or control between March 16, 2021, and February 25, 2022, at 69 sites in 7 countries (final follow-up on June 1, 2022). INTERVENTIONS Patients were randomized to receive open-label initiation of an ACE inhibitor (n = 257), ARB (n = 248), ARB in combination with DMX-200 (a chemokine receptor-2 inhibitor; n = 10), or no RAS inhibitor (control; n = 264) for up to 10 days. MAIN OUTCOMES AND MEASURES The primary outcome was organ support–free days, a composite of hospital survival and days alive without cardiovascular or respiratory organ support through 21 days. The primary analysis was a bayesian cumulative logistic model. Odds ratios (ORs) greater than 1 represent improved outcomes. RESULTS On February 25, 2022, enrollment was discontinued due to safety concerns. Among 679 critically ill patients with available primary outcome data, the median age was 56 years and 239 participants (35.2%) were women. Median (IQR) organ support–free days among critically ill patients was 10 (–1 to 16) in the ACE inhibitor group (n = 231), 8 (–1 to 17) in the ARB group (n = 217), and 12 (0 to 17) in the control group (n = 231) (median adjusted odds ratios of 0.77 [95% bayesian credible interval, 0.58-1.06] for improvement for ACE inhibitor and 0.76 [95% credible interval, 0.56-1.05] for ARB compared with control). The posterior probabilities that ACE inhibitors and ARBs worsened organ support–free days compared with control were 94.9% and 95.4%, respectively. Hospital survival occurred in 166 of 231 critically ill participants (71.9%) in the ACE inhibitor group, 152 of 217 (70.0%) in the ARB group, and 182 of 231 (78.8%) in the control group (posterior probabilities that ACE inhibitor and ARB worsened hospital survival compared with control were 95.3% and 98.1%, respectively). CONCLUSIONS AND RELEVANCE In this trial, among critically ill adults with COVID-19, initiation of an ACE inhibitor or ARB did not improve, and likely worsened, clinical outcomes. TRIAL REGISTRATION ClinicalTrials.gov Identifier: NCT0273570