St. Louis Area Earthquake Hazards Mapping Project: Seismic and Liquefaction Hazard Maps

We present probabilistic and deterministic seismic and liquefaction hazard maps for the densely populated St. Louis metropolitan area that account for the expected effects of surficial geology on earthquake ground shaking. Hazard calculations were based on a map grid of 0.005°, or about every 500 m, and are thus higher in resolution than any earlier studies. To estimate ground motions at the surface of the model (e.g., site amplification), we used a new detailed near-surface shear-wave velocity model in a 1D equivalent- linear response analysis. When compared with the 2014 U.S. Geological Survey (USGS) National Seismic Hazard Model, which uses a uniform firm-rock-site condition, the new probabilistic seismic-hazard estimates document much more variability. Hazard levels for upland sites (consisting of bedrock and weathered bedrock overlain by loess-covered till and drift deposits), show up to twice the ground-motion values for peak ground acceleration (PGA), and similar ground-motion values for 1.0 s spectral acceleration (SA). Probabilistic ground-motion levels for lowland alluvial floodplain sites (generally the 20-40-m-thick modern Mississippi and Missouri River floodplain deposits overlying bedrock) exhibit up to twice the ground-motion levels for PGA, and up to three times the ground-motion levels for 1.0 s SA. Liquefaction probability curves were developed from available standard penetration test data assuming typical lowland and upland water table levels. A simplified liquefaction hazard map was created from the 5%-in-50-year probabilistic ground-shaking model. The liquefaction hazard ranges from low (\u3c40% of area expected to liquefy) in the uplands to severe (\u3e60% of area expected to liquefy) in the lowlands. Because many transportation routes, power and gas transmission lines, and population centers exist in or on the highly susceptible lowland alluvium, these areas in the St. Louis region are at significant potential risk from seismically induced liquefaction and associated ground deformation

An Assessment of H1N1 Influenza-Associated Acute Respiratory Distress Syndrome Severity after Adjustment for Treatment Characteristics

Pandemic influenza caused significant increases in healthcare utilization across several continents including the use of high-intensity rescue therapies like extracorporeal membrane oxygenation (ECMO) or high-frequency oscillatory ventilation (HFOV). The severity of illness observed with pandemic influenza in 2009 strained healthcare resources. Because lung injury in ARDS can be influenced by daily management and multiple organ failure, we performed a retrospective cohort study to understand the severity of H1N1 associated ARDS after adjustment for treatment. Sixty subjects were identified in our hospital with ARDS from “direct injury” within 24 hours of ICU admission over a three month period. Twenty-three subjects (38.3%) were positive for H1N1 within 72 hours of hospitalization. These cases of H1N1-associated ARDS were compared to non-H1N1 associated ARDS patients. Subjects with H1N1-associated ARDS were younger and more likely to have a higher body mass index (BMI), present more rapidly and have worse oxygenation. Severity of illness (SOFA score) was directly related to worse oxygenation. Management was similar between the two groups on the day of admission and subsequent five days with respect to tidal volumes used, fluid balance and transfusion practices. There was, however, more frequent use of “rescue” therapy like prone ventilation, HFOV or ECMO in H1N1 patients. First morning set tidal volumes and BMI were significantly associated with increased severity of lung injury (Lung injury score, LIS) at presentation and over time while prior prescription of statins was protective. After assessment of the effect of these co-interventions LIS was significantly higher in H1N1 patients. Patients with pandemic influenza-associated ARDS had higher LIS both at presentation and over the course of the first six days of treatment when compared to non-H1N1 associated ARDS controls. The difference in LIS persisted over the duration of observation in patients with H1N1 possibly explaining the increased duration of mechanical ventilation

Anticipating and Adapting to the Future Impacts of Climate Change on the Health, Security and Welfare of Low Elevation Coastal Zone (LECZ) Communities in Southeastern USA

Low elevation coastal zones (LECZ) are extensive throughout the southeastern United States. LECZ communities are threatened by inundation from sea level rise, storm surge, wetland degradation, land subsidence, and hydrological flooding. Communication among scientists, stakeholders, policy makers and minority and poor residents must improve. We must predict processes spanning the ecological, physical, social, and health sciences. Communities need to address linkages of (1) human and socioeconomic vulnerabilities; (2) public health and safety; (3) economic concerns; (4) land loss; (5) wetland threats; and (6) coastal inundation. Essential capabilities must include a network to assemble and distribute data and model code to assess risk and its causes, support adaptive management, and improve the resiliency of communities. Better communication of information and understanding among residents and officials is essential. Here we review recent background literature on these matters and offer recommendations for integrating natural and social sciences. We advocate for a cyber-network of scientists, modelers, engineers, educators, and stakeholders from academia, federal state and local agencies, non-governmental organizations, residents, and the private sector. Our vision is to enhance future resilience of LECZ communities by offering approaches to mitigate hazards to human health, safety and welfare and reduce impacts to coastal residents and industries

Deficit Irrigation Management of Maize in the High Plains Aquifer Region: A Review

Irrigated agriculture is a major economic contributor of the High Plains Region and it primarily relies on the High Plains Aquifer as a source of water. Over time, areas of the High Plains Aquifer have experienced drawdowns limiting its ability to supply sufficient water to sustain fully irrigated crop production. This among other reasons, including variable climatic factors and differences in state water policy, has resulted in some areas adopting and practicing deficit irrigation management. Considerable research has been conducted across the High Plains Aquifer region to identify locally appropriate deficit irrigation strategies. This review summarizes and discusses research conducted in Nebraska, Colorado, Kansas, and Texas, as well as highlights areas for future research. Editor’s note: This paper is part of the featured series on Optimizing Ogallala Aquifer Water Use to Sustain Food Systems. See the February 2019 issue for the introduction and background to the series