Discrepancies in Mass Shootings and Access to Trauma Care Across the United States, 2014-2018.

INTRODUCTION: The United States has one of the highest rates of gun violence and mass shootings. Timely medical attention in such events is critical. The objective of this study was to assess geographic disparities in mass shootings and access to trauma centers. METHODS: Data for all Level I and II trauma centers were extracted from the American College of Surgeons and the Trauma Center Association of America registries. Mass shooting event data (4+ individuals shot at a single event) were taken from the Gun Violence Archive between 2014 and 2018. RESULTS: A total of 564 trauma centers and 1672 mass shootings were included. Ratios of the number of mass shootings vs trauma centers per state ranged from 0 to 11.0 mass shootings per trauma center. States with the greatest disparity (highest ratio) included Louisiana and New Mexico. CONCLUSION: States in the southern regions of the US experience the greatest disparity due to a high burden of mass shootings with less access to trauma centers. Interventions are needed to increase access to trauma care and reduce mass shootings in these medically underserved areas.

Comparative analysis of three next-generation sequencing techniques to measure nosZ gene abundance in Missouri claypan soils.

Quantitative next-generation sequencing techniques have been critical in gaining a better understanding of microbial ecosystems. In soils, denitrifying microorganisms are responsible for dinitrogen (N2) production. The nosZ gene codes for nitrous oxide reductase, the enzyme facilitating the reduction of nitrous oxide (N2O) to N2. The objectives of this research were to: 1) understand how soil depth influences RNA concentration and nosZ gene abundance; 2) assess the spatial dependence of nosZ gene abundance in two claypan soil fields; and 3) compare and evaluate multiple RNA-based sequencing methods for quantifying nosZ gene abundance in soils in relation to dinitrogen (N2) production. Research sites consisted of two intensively studied claypan soil fields in Central Missouri, USA. Soil cores were collected from two landscape transects across both fields and analyzed for extractable soil RNA at two depths (0-15 cm and 15-30 cm). Measurements of nosZ gene abundance were obtained using real-time quantitative polymerase chain reaction (RT-qPCR), droplet digital polymerase chain reaction (ddPCR), and nanostring sequencing (NS). In both fields, soil RNA concentrations were significantly greater at 0-15 cm depth compared to 15-30 cm. These data indicated low overall soil microbial activity below 15 cm. Due to low quantities of extractable soil RNA in the subsoil, nosZ gene abundance was only determined in the 0-15 cm depth. Sequencing method comparisons of average nosZ gene abundance showed that NS results were constrained to a narrow range and were 10-20-fold lower than ddPCR and RT-qPCR at each landscape position within each field. Droplet digital PCR appears to be the most promising method, as it reflected changes in N2 production across landscape position.

The COVID-19 pandemic and its impacts on mass shootings in six major US cities.

BACKGROUND: The COVID-19 pandemic has significant impacts on the US socioeconomic structure. Gun violence is a major public health issue and the effects on this area have not been well-elucidated. The objective of this study was to determine the impacts of the pandemic on mass shootings in six major United States cities with historically high rates of gun violence. METHODS: Mass shooting data were extracted from an open-source database, Gun Violence Archive. Mass shooting was defined as four or more people shot at a single event. Data from six cities with the highest incidence of mass shootings were analyzed in 2019 versus 2020 (Baltimore, Chicago, Detroit, New Orleans, Philadelphia, and St. Louis). Geographic data were examined to assess changes in each city's mass shooting geographic distribution over time. Quantitative changes were assessed using the Area Deprivation Index (ADI), and qualitative data were assessed using ArcGIS. RESULTS: In 2020, the overall percentage of mass shootings increased by 46.7% though there was no change in the distribution of these events when assessed quantitatively (no change in average ADI) nor qualitatively (using ArcGIS). In the six cities analyzed, the total proportion of mass shooting events was unchanged during the pandemic (21.8% vs 20.6%, p = 0.64). Chicago, the US city with the highest incidence of mass shootings, did not experience a significant change in 2020 (n = 34/91, 37.3% vs. n = 53/126, 42.1%, p = 0.57). Baltimore had a significant decrease in mass shooting events (n = 18/91, 19.8% vs. 10/126, 7.9%, p = 0.01). The other four cities had no significant change in the number of mass shootings (p>0.05). CONCLUSION: This study is the first to use ArcGIS technology to describe the patterns of mass shooting in six major US cities during the COVID-19 pandemic. The number of mass shootings in six US cities remained largely unchanged which suggests that changes in mass shootings is likely occurring in smaller cities. Future studies should focus on the changing patterns of homicides in at-risk communities and other possible social influences.

A Case Study of Environmental Benefits of Sensor-Based Nitrogen Application in Corn.

Crop canopy reflectance sensors make it possible to estimate crop N demand and apply appropriate N fertilizer rates at different locations in a field, reducing fertilizer input and associated environmental impacts while maintaining crop yield. Environmental benefits, however, have not been quantified previously. The objective of this study was to estimate the environmental impact of sensor-based N fertilization of corn using model-based environmental Life Cycle Assessment. Nitrogen rate and corn grain yield were measured during a sensor-based, variable N-rate experiment in Lincoln County, MO. Spatially explicit soil properties were derived using a predictive modeling technique based on in-field soil sampling. Soil NO emissions, volatilized NH loss, and soil NO leaching were predicted at 60 discrete field locations using the DeNitrification-DeComposition (DNDC) model. Life cycle cumulative energy consumption, global warming potential (GWP), acidification potential, and eutrophication potential were estimated using model predictions, experimental data, and life cycle data. In this experiment, variable-rate N management reduced total N fertilizer use by 11% without decreasing grain yield. Precision application of N is predicted to have reduced soil NO emissions by 10%, volatilized NH loss by 23%, and NO leaching by 16%, which in turn reduced life cycle nonrenewable energy consumption, GWP, acidification potential, and eutrophication potential by 7, 10, 22, and 16%, respectively. Although mean N losses were reduced, the variations in N losses were increased compared with conventional, uniform N application. Crop canopy sensor-based, variable-rate N fertilization was predicted to increase corn grain N use efficiency while simultaneously reducing total life-cycle energy use, GWP, acidification, and eutrophication.

Economically optimal nitrogen rate reduces soil residual nitrate.

Post-harvest residual soil NO(3)-N (RSN) is susceptible to transfer to water resources. Practices that minimize RSN levels can reduce N loss to the environment. Our objectives were (i) to determine if the RSN after corn (Zea mays L.) harvest can be reduced if N fertilizer is applied at the economically optimal N rate (EONR) as compared to current producer practices in the midwestern USA and (ii) to compare RSN levels for N fertilizer rates below, at, and above the EONR. Six experiments were conducted in producer fields in three major soil areas (Mississippi Delta alluvial, deep loess, claypan) in Missouri over 2 yr. Predominant soil great groups were Albaqualfs, Argiudolls, Haplaquolls, and Fluvaquents. At four transects in each field, six treatment N rates from 0 to 280 kg N ha(-1) were applied, the EONR was determined, and the RSN was measured to a 0.9-m depth from five treatment plots. The EONR at sampling sites varied from 49 to 228 kg N ha(-1) depending on site and year. Estimated average RSN at the EONR was 33 kg N ha(-1) in the 0.9-m profile. This was at least 12 kg N ha(-1) lower than RSN at the producers' N rates. The RSN increased with increasing Delta EONR (total N applied - EONR). This relationship was best modeled by a plateau-linear function, with a low RSN plateau at N rates well below the EONR. A linear increase in RSN began anywhere from 65 kg N ha(-1) below the EONR to 20 kg N ha(-1) above the EONR at the three sites with good data resolution near the EONR. Applying N rates in excess of the EONR produced elevated RSN values in all six experiments. Our results suggest that applying the EONR will produce environmental benefits in an economically sound manner, and that continued attempts to develop methods for accurately predicting EONR are justified.