Multiple Mitigation Strategies Research Articles

Exploring Thermal Discomfort during Mediterranean Heatwaves through Softscape and Hardscape ENVI-Met Simulation Scenarios

The study examines the effectiveness of various design strategies in alleviating the impacts of heatwaves in the Mediterranean region, focusing on a densely populated post-refugee urban area in Greece. By analyzing five different design scenarios, the study aims to identify the most efficient approach to mitigate thermal stress outdoors. The five design scenarios include changes in albedo values and coatings and alterations in the number and type of trees. The methodology includes a literature review, field work and microclimate simulations with the use of ENVI-met 5.6.1. The study evaluates ENVI-met data through potential air temperature, PET and UTCI analysis. The experimental results indicate that the most effective strategy is associated with urban greening. In particular, increasing tree cover considerably reduces air temperature, PET and UTCI values by 4 to 10 degrees Celsius. This finding highlights the potential of urban greening to enhance thermal comfort and combat heatwave effects. The research findings may be useful to landscape architects and urban designers, in light of a more climate-responsive urban design in the Mediterranean region. Future research may also assess the combined impact of multiple mitigation strategies on a larger scale, informing evidence-based policies for heatwave resilience.

Evaluation of White Rot Fungus to Control Growth of Escherichia coli in Cattle Manure

Biological soil amendments of animal origin, such as aqueous dairy manure, may be contaminated with microbial pathogens that can subsequently result in contaminated soil, water runoff, and crops. Multiple mitigation strategies are being evaluated to reduce these risks. Inclusion of filamentous fungus in a biofiltration system to inactivate pathogenic bacteria in aqueous dairy manure prior to land application is explored in this study as a preharvest preventative method. Of the microbes used to remediate biologically contaminated sites, ligninolytic white-rot fungi have been previously studied for their ability to degrade a wide variety of toxic or persistent environmental contaminants. Reduction of two E. coli strains (E. coli TVS355 and E. coli O157:H7 4407) was evaluated in aqueous dairy manure and PBS and in the presence of white-rot fungi Pleurotus ostreatus on three different nutrient sources (woodchips (WC), spent mushroom compost (SMC), and reticulated polyurethane foam (RPF)). Overall, E. coli TVS355 was more persistent in aqueous dairy manure and PBS, surviving for 50 days in the presence of P. ostreatus, with a final concentration of 4 log CFU/g in aqueous manure and 7 log CFU/g in PBS. However, greater (p < 0.0001) reduction of E. coli O157:H7 was observed, surviving for 50 days at an average of 4 log CFU/g in aqueous dairy manure and an average of 3 log CFU/g in PBS. Therefore, P. ostreatus has the potential to result in bacterial decay, with potential reduction observed in E. coli O157:H7. The RPF matrix showed positive results as a potential model for a nutrient limiting resource for P. ostreatus and could be the key to increased bacterial reductions if resulting in ligninolytic activity in order to seek other nutrient sources.

Geomagnetically Induced Current Mitigation in New Zealand: Operational Mitigation Method Development With Industry Input

AbstractReducing the impact of Geomagnetically induced currents (GICs) on electrical power networks is an essential step to protect network assets and maintain reliable power transmission during and after storm events. In this study, multiple mitigation strategies are tested during worst‐case extreme storm scenarios in order to investigate their effectiveness for the New Zealand transmission network. By working directly with our industry partners, Transpower New Zealand Ltd, a mitigation strategy in the form of targeted line disconnections has been developed. This mitigation strategy proved more effective than previous strategies at reducing GIC magnitudes and durations at transformers at most risk to GIC while still maintaining the continuous supply of power throughout New Zealand. Under this mitigation plan, the average 60‐min mean GIC decreased for 27 of the top 30 at‐risk transformers, and the total network GIC was reduced by 16%. This updated mitigation has been adopted as an operational procedure in the New Zealand national control room to manage GIC. In addition, simulations show that the installation of 14 capacitor blocking devices at specific transformers reduces the total GIC sum in the network by an additional 16%. As a result of this study Transpower is considering further mitigation in the form of capacitor blockers. We strongly recommend collaborating with the relevant power network providers to develop effective mitigation strategies that reduce GIC and have a minimal impact on power distribution.

The Experiences of Skilled Nursing Staff in Memory Care Units During the COVID-19 Pandemic.

The novel coronavirus disease 2019 (COVID-19) resulted in the need for multiple mitigation strategies. The impacts of these safety measures were felt more extremely by healthcare providers. This qualitative study focused on the experiences of staff in skilled nursing facilities, specifically in locked memory care units, during the first year of the COVID-19 pandemic. This study used a basic interpretive methodology. In-depth interviews were conducted with skilled nursing staff members who worked in a locked memory care unit during the 2020 calendar year. Thematic analysis was used to organize and interpret the data. A total of 11 participants provided data that resulted in themes around reasons for working on a locked memory care unit, experiences working with people who have behavioral and psychological symptoms due to dementia, training, outcomes of shared experiences, outcomes of policy changes, management support, and suggestions for a future pandemic. The results of this study may have implications for skilled nursing facilities with locked memory care units that continue to grapple with the realities of providing care during a pandemic. Providing appropriate training, social support, and appropriate protective equipment are among the suggestions.

The Impact of Hurricane Ida on Emergency Medical Services Operations in New Orleans

Introduction:On August 29, 2021 Hurricane Ida struck New Orleans with Category 4 winds. While the most severe weather occurred during a 24-hr period on August 29, the city suffered significant damage to telecommunication systems, medical facilities, and infrastructure for several weeks afterward. At the height of the storm, multiple events affected routine deployment of EMS, including damage to transmission lines causing interruption of the 911 system, and suspension of ambulance travel for safety when the winds exceeded 50 mph. These factors, as well as pre-storm preparations, affected utilization of EMS by residents and thus a “peri-hurricane” period was examined to determine the overall effect of Hurricane Ida on New Orleans EMS operations.Method:Run sheets for calls to NOEMS between August 26-September 9, 2021 were analyzed to assess the most frequently reported medical complaint just prior to and after the hurricane. Run sheets were also evaluated to determine average time from call to arrival on scene, time to arrival at patient (“response time”), and time from leaving scene to arrival at destination (“transport time”). To account for the atypical period during which EMS response was suspended due to wind, both mean and median times were calculated. Data was compared to a control period of Aug 26-Sept 9, 2022.Results:During the study period, 1,971 calls were received, with trauma and respiratory the most common complaints. The mean call-to-arrival time was one hour, although the median time was 15 minutes. Response time was 34 minutes compared to 21 minutes in 2022, and median response time was comparable to the control period. Transport time mean and median were 12.3 and 11.3 minutes, also similar to 2022.Conclusion:Despite citywide infrastructure failures and suspension of operations for over 12 hours during landfall, multiple mitigation strategies enabled NOEMS to quickly resume operations and minimize impact on patient care times.

“Sorry, I don’t good English”: Japanese L2 students’ written peer feedback in the face-to-face and anonymous review modes

To verify and extend the previous research claim that L2 students from collectivistic Asian cultures are resistant to criticizing others’ work due to a desire to preserve group cohesion, this study explored whether anonymity helps ameliorate their alleged reluctance to give negative feedback. Nineteen Japanese L2 students reviewed essays in the face-to-face and anonymous modes, and their feedback comments were comparatively analyzed according to the types, levels of negativity, and mitigation strategies implemented. The results showed that Japanese L2 students adopt an extremely polite interpersonal rhetorical stance regardless of the peer review mode. Criticism almost always assumes a mitigated form, and it is not uncommon to employ multiple mitigation strategies or lexical hedges in a single comment. The pragmatic competence with respect to hedging disagreement or requests did not correlate with the language used or the reviewer’s L2 proficiency. These observations suggest that the use of mitigating devices is transferred from learners’ L1 repertoire, indicating that cultural attributes might not be a major factor influencing Asian students’ reluctance to provide negative feedback in peer interactions.

A longitudinal study to examine the influence of farming practices and environmental factors on pathogen prevalence using structural equation modeling.

The contamination of fresh produce with foodborne pathogens has been an on-going concern with outbreaks linked to these commodities. Evaluation of farm practices, such as use of manure, irrigation water source, and other factors that could influence pathogen prevalence in the farming environment could lead to improved mitigation strategies to reduce the potential for contamination events. Soil, water, manure, and compost were sampled from farms in Ohio and Georgia to identify the prevalence of Salmonella, Listeria monocytogenes (Lm), Campylobacter, and Shiga-toxin-producing Escherichia coli (STEC), as well as Arcobacter, an emerging human pathogen. This study investigated agricultural practices to determine which influenced pathogen prevalence, i.e., the percent positive samples. These efforts identified a low prevalence of Salmonella, STEC, and Campylobacter in soil and water (< 10%), preventing statistical modeling of these pathogens. However, Lm and Arcobacter were found in soil (13 and 7%, respectively), manure (49 and 32%, respectively), and water samples (18 and 39%, respectively) at a comparatively higher prevalence, suggesting different dynamics are involved in their survival in the farm environment. Lm and Arcobacter prevalence data, soil chemical characteristics, as well as farm practices and weather, were analyzed using structural equation modeling to identify which factors play a role, directly or indirectly, on the prevalence of these pathogens. These analyses identified an association between pathogen prevalence and weather, as well as biological soil amendments of animal origin. Increasing air temperature increased Arcobacter and decreased Lm. Lm prevalence was found to be inversely correlated with the use of surface water for irrigation, despite a high Lm prevalence in surface water suggesting other factors may play a role. Furthermore, Lm prevalence increased when the microbiome's Simpson's Diversity Index decreased, which occurred as soil fertility increased, leading to an indirect positive effect for soil fertility on Lm prevalence. These results suggest that pathogen, environment, and farm management practices, in addition to produce commodities, all need to be considered when developing mitigation strategies. The prevalence of Arcobacter and Lm versus the other pathogens suggests that multiple mitigation strategies may need to be employed to control these pathogens.

Improving OFF-State Bias-Stress Stability in High-Mobility Conjugated Polymer Transistors with an Antisolvent Treatment.

Conjugated polymer field-effect transistors are emerging as an enabling technology for flexible electronics due to their excellent mechanical properties combined with sufficiently high charge-carrier mobilities and compatibility with large-area, low-temperature processing. However, their electrical stability remains a concern. ON-state (accumulation mode) bias-stress instabilities in organic semiconductors have been widely studied, and multiple mitigation strategies have been suggested. In contrast, OFF-state (depletion mode) bias-stress instabilities remain poorly understood despite being crucial for many applications in which the transistors are held in their OFF-state for most of the time. Here, a simple method of using an antisolvent treatment is presented to achieve significant improvements in OFF-state bias-stress and environmental stability as well as general device performance for one of the best performing polymers, solution-processable indacenodithiophene-co-benzothiadiazole (IDT-BT). IDT-BT is weakly crystalline, and the notable improvements to an antisolvent-induced, increased degree of crystallinity, resulting in a lower probability of electron trapping and the removal of charge traps is attributed. The work highlights the importance of the microstructure in weakly crystalline polymer films and offers a simple processing strategy for achieving the reliability required for applications in flexible electronics.

COVID-19 and Courts: An Exploration of the Impacts of the Pandemic on Case Processing and Operations

ABSTRACT The COVID-19 pandemic instantly changed the day-to-day practices of the criminal justice system. The court system, traditionally reliant on face-to-face interaction, had to quickly alter operations to decrease the virus’ spread while remaining functional as an integral role in the criminal justice system. The current exploratory study examines the response strategies U.S. court systems implemented, impacts on case processing, case backlogs, and additional consequences endured due to the pandemic. Using responses from self-report surveys of court staff (e.g., judges, clerks), results indicated that courts prioritized the types of cases heard and implemented multiple mitigation strategies that were deemed effective, some of which may be sustainable post-pandemic. Despite an increase in virtual jury trials and hearings, many courts saw a surge in backlogged cases and complications in assembling juries. The overall findings may inform judiciary policy and practice concerning short and long-term pandemic outcomes on court processing and future pandemic preparedness.

Chilean pathways for mid-century carbon neutrality under high renewable potential

Implementing nationally determined contributions is more challenging for developing countries given potential economic consequences. Chile, a developing economy, is committed to reaching carbon neutrality by 2050. To do so, Chile announced multiple mitigation strategies such as phasing out coal by 2040, peaking emissions by 2025, and developing renewable energies. Fortunately, Chile holds a prominent renewable potential, standing out for solar, but it also has a significant challenge decarbonizing an economy that heavily relies on fossil fuels. The contribution of this paper is twofold. First, the first country-level disaggregated version of GCAM Latin America (GCAM-LA) was developed, where all South American countries are modeled as an independent energy-economy region. This model includes Chile as a separated region and incorporates interactions among the energy, water, agriculture and land use, economy, and climate systems. Second, different decarbonization strategies to reach carbon neutrality by 2050 were obtained, considering technology availability and high renewable energy potential. Results indicate that carbon neutrality is feasible when enforcing different combinations of the current Chilean mitigation strategies, even delaying coal phase-out by five years and failure of developing advanced solar technologies. If some policies are not fully implemented, such as delaying coal phase-out by five years or failure of developing advanced solar technologies, carbon neutrality can be achieved by incurring in a higher capital cost in the power sector. Moreover, decarbonization is mainly driven by high electrification levels in the final demand sector, reaching 53.7%–62.9% of the total consumption. However, such levels of electrification are reduced, particularly in the transport sector, when Chile relies on negative emissions from the land use and forestry sector.

Assessing catchment scale water quality of agri-food systems and the scope for reducing unintended consequences using spatial life cycle assessment (LCA).

Life cycle assessment is a multidisciplinary framework usually deployed to appraise the sustainability of various product or service supply-chains. Over recent decades, its use in the agri-food sector has risen sharply, and alongside this, a wide range of methodological advances have been generated. Spatial-life cycle assessment, defined in the current document as the interpretation of life cycle assessment results within a geographical nature, has not gone unexplored entirely, yet its rise as a sub-method of life cycle assessment has been rather slow relative to other avenues of research (e.g., including the nutritional sciences within life cycle assessment). With this relative methodological stagnation as a motivating factor, our paper combines a process-based model, the Catchment Systems Model, with various life cycle impact assessments (ReCiPe, Centre for Environmental Studies and Environmental Product Declaration) to propose a simple, yet effective, approach for visualising the technically feasible efficacy of various on-farm intervention strategies. As water quality was the primary focus of this study, interventions reducing acidification and eutrophication potentials of both arable and livestock farm types in the Southeast of England were considered. The study site is an area with a marked range of agricultural practices in terms of intensity. All impacts to acidification potential and eutrophication potential are reported using a functional unit of 1ha. Percentage changes relative to baseline farm types, i.e., those without any interventions, arising from various mitigation strategies, are mapped using geographical information systems. This approach demonstrates visually how a spatially-orientated life cycle assessment could provide regional-specific information for farmers and policymakers to guide the restoration of certain waterbodies. A combination of multiple mitigation strategies was found to generate the greatest reductions in pollutant losses to water, but in terms of individual interventions, optimising farm-based machinery (acidification potential) and fertiliser application strategies (eutrophication potential) were found to have notable benefits.

On steady state noncondensable gas buildup in Autonomous Reactivity Control (ARC) systems

The Autonomous Reactivity Control (ARC) system, a new engineered passive safety system for liquid metal reactors, has been the subject of many recent studies, having shown the potential to improve both safety and performance of liquid metal reactors while introducing only a minor impact on normal operations. This study investigates one area of ARC system performance which has not yet been examined — the production of internal noncondensable gases during normal operations. Using neutronic calculations, this study finds that a non-negligible quantity of gases will be produced through transmutation reactions of the internal ARC system fluids, and a lower bound on this quantity is calculated. Through a series of geometric arguments and considerations on mutual solubility and chemical reactivity, the volume and distribution of noncondensable gas buildup is examined for a wide range of ARC system designs. To demonstrate the impact of these noncondensable gases, a series of thermal-hydraulic and transient calculations are performed, and it is shown that the production of noncondensable gases from transmutation of the liquid potassium expander fluid will have negative impacts on the performance of the ARC system, causing an unsteady and restricted actuation which will lead to a reduction of benefits for a given reactor’s transient performance and an increased uncertainty on the state of the system during reactor operations. In the end, multiple mitigation strategies are discussed, but ultimately this study motivates a reevaluation of the fundamental ARC system design so that its benefits may be most fully realized.

Emission estimates and inventories of non-methane volatile organic compounds from anthropogenic burning sources in India

Comprehensive, spatially disaggregated emission inventories are required for many developing regions to evaluate the relative impacts of different sources and to develop mitigation strategies which can lead to effective emission controls. This study developed a 1 km 2 non-methane volatile organic compound (NMVOC) emission model for the combustion of fuel wood, cow dung cake, municipal solid waste (MSW), charcoal, coal and liquefied petroleum gas (LPG) in India from 1993 to 2016. Inputs were selected from a range of detailed fuel consumption surveys and recent emission factors measured during comprehensive studies of local burning sources. For the census year of 2011, we estimated around 13 (5–47) Tg of NMVOCs were emitted from biomass and MSW combustion in India. Around 54% of these emissions were from residential solid biofuel combustion, 23% from open burning of MSW, 23% from crop residue burning on fields and <1% from LPG for cooking. NMVOC emissions from residential combustion were shown to be highly sensitive to the amount of cow dung cake combusted and this acted as a key pollution source across the Indo-Gangetic Plain. The results of this study indicate that multiple mitigation strategies are required across several different categories of burning source to achieve effective NMVOC emission reduction. • New emission inventories developed for burning sources in India. • Estimates made for non-methane volatile organic compounds. • Estimates made for polycyclic aromatic hydrocarbons. • Pollution from cow dung cake combustion significant to North of India. • Waste and crop residue burning also significant pollution sources.

The Driving Influence of Multi-Dimensional Urbanization on PM2.5 Concentrations in Africa: New Evidence from Multi-Source Remote Sensing Data, 2000-2018.

Africa’s PM2.5 pollution has become a security hazard, but the understanding of the varying effects of urbanization on driven mechanisms of PM2.5 concentrations under the rapid urbanization remains largely insufficient. Compared with the direct impact, the spillover effect of urbanization on PM2.5 concentrations in adjacent regions was underestimated. Urbanization is highly multi-dimensional phenomenon and previous studies have rarely distinguished the different driving influence and interactions of multi-dimensional urbanization on PM2.5 concentrations in Africa. This study combined grid and administrative units to explore the spatio-temporal change, spatial dependence patterns, and evolution trend of PM2.5 concentrations and multi-dimensional urbanization in Africa. The differential influence and interaction effects of multi-dimensional urbanization on PM2.5 concentrations under Africa’s rapid urbanization was further analyzed. The results show that the positive spatial dependence of PM2.5 concentrations gradually increased over the study period 2000–2018. The areas with PM2.5 concentrations exceeding 35 μg/m3 increased by 2.2%, and 36.78% of the African continent had an increasing trend in Theil–Sen index. Urbanization was found to be the main driving factor causing PM2.5 concentrations changes, and economic urbanization had a stronger influence on air quality than land urbanization or population urbanization. Compared with the direct effect, the spillover effect of urbanization on PM2.5 concentrations in two adjacent regions was stronger, particularly in terms of economic urbanization. The spatial distribution of PM2.5 concentrations resulted from the interaction of multi-dimensional urbanization. The interaction of urbanization of any two different dimensions exhibited a nonlinear enhancement effect on PM2.5 concentrations. Given the differential impact of multi-dimensional urbanization on PM2.5 concentrations inside and outside the region, this research provides support for the cross-regional joint control strategies of air pollution in Africa. The findings also indicate that PM2.5 pollution control should not only focus on urban economic development strategies but should be an optimized integration of multiple mitigation strategies, such as improving residents’ lifestyles, optimizing land spatial structure, and upgrading the industrial structure.

Surgically generated aerosol and mitigation strategies: combined use of irrigation, respirators and suction massively reduces particulate matter aerosol

BackgroundAerosol is a health risk to theatre staff. This laboratory study quantifies the reduction in particulate matter aerosol concentrations produced by electrocautery and drilling when using mitigation strategies such as irrigation, respirator filtration and suction in a lab environment to prepare for future work under live OR conditions.MethodsWe combined one aerosol-generating procedure (monopolar cutting or coagulating diathermy or high-speed diamond- or steel-tipped drilling of cadaveric porcine tissue) with one or multiple mitigation strategies (instrument irrigation, plume suction and filtration using an FFP3 respirator filter) and using an optical particle counter to measure particulate matter aerosol size and concentrations.ResultsSignificant aerosol concentrations were observed during all aerosol-generating procedures with concentrations exceeding 3 × 106 particles per 100 ml. Considerable reductions in concentrations were observed with mitigation. In drilling, suction, FFP3 filtration and wash alone respectively reduced aerosol by 19.3–31.6%, 65.1–70.8% and 97.2 to > 99.9%. The greatest reduction (97.38 to > 99.9%) was observed when combining irrigation and filtration. Coagulating diathermy reduced concentrations by 88.0–96.6% relative to cutting, but produced larger particles. Suction alone, and suction with filtration reduced aerosol concentration by 41.0–49.6% and 88.9–97.4% respectively. No tested mitigation strategies returned aerosol concentrations to baseline.ConclusionAerosol concentrations are significantly reduced through the combined use of filtration, suction and irrigation. Further research is required to characterise aerosol concentrations in the live OR and to find acceptable exposure limits, and in their absence, to find methods to further reduce exposure to theatre staff.

Modeling the Transmission of COVID-19: Impact of Mitigation Strategies in Prekindergarten-Grade 12 Public Schools, United States, 2021.

Schools are an integral part of the community; however, congregate settings facilitate transmission of SARS-CoV-2, presenting a challenge to school administrators to provide a safe, in-school environment for students and staff. We adapted the Centers for Disease Control and Prevention's COVIDTracer Advanced tool to model the transmission of SARS-CoV-2 in a school of 596 individuals. We estimate possible reductions in cases and hospitalizations among this population using a scenario-based analysis that accounts for (a) the risk of importation of infection from the community; (b) adherence to key Centers for Disease Control and Prevention-recommended mitigation strategies: mask wearing, cleaning and disinfection, hand hygiene, and social distancing; and (c) the effectiveness of contact tracing interventions at limiting onward transmission. Low impact and effectiveness of mitigation strategies (net effectiveness: 27%) result in approximately 40% of exposed staff and students becoming COVID-19 cases. When the net effectiveness of mitigation strategies was 69% or greater, in-school transmission was mostly prevented, yet importation of cases from the surrounding community could result in nearly 20% of the school's population becoming infected within 180 days. The combined effects of mitigation strategies and contact tracing were able to prevent most onward transmission. Hospitalizations were low among children and adults (<0.5% of the school population) across all scenarios examined. Based on our model, layering mitigation strategies and contact tracing can limit the number of cases that may occur from transmission in schools. Schools in communities with substantial levels of community spread will need to be more vigilant to ensure adherence of mitigation strategies to minimize transmission. Our results show that for school administrators, teachers, and parents to provide the safest environment, it is important to utilize multiple mitigation strategies and contract tracing that reduce SARS CoV-2 transmission by at least 69%. This will require training, reinforcement, and vigilance to ensure that the highest level of adherence is maintained over the entire school term.

Disentangling the environmental processes responsible for the world's largest farmed fish-killing harmful algal bloom: Chile, 2016

The dictyochophyte microalga Pseudochattonella verruculosa was responsible for the largest farmed fish mortality ever recorded in the world, with losses for the Chilean salmon industry amounting to US$ 800 M in austral summer 2016. Super-scale climatic anomalies resulted in strong vertical water column stratification that stimulated development of a dynamic P. verruculosa thin layer (up to 38 μg chl a L−1) for several weeks in Reloncaví Sound. Hydrodynamic modeling (MIKE 3D) indicated that the Sound had extremely low flushing rates (between 121 and 200 days) in summer 2016. Reported algal cell densities of 7000–20,000 cells mL−1 generated respiratory distress in fish that was unlikely due to low dissolved oxygen (permanently >4 mg L−1). Histological examination of salmon showed that gills were the most affected organ with significant tissue damage and circulatory disorders. It is possible that some of this damage was due to a diatom bloom that preceded the Pseudochattonella event, thereby rendering the fish more susceptible to Pseudochattonella. No correlation between magnitude of fish mortality and algal cell abundance nor fish age was evident. Algal cultures revealed rapid growth rates and high cell densities (up to 600,000 cells mL−1), as well as highly complex life cycle stages that can be easily overlooked in monitoring programs. In cell-based bioassays, Chilean P. verruculosa was only toxic to the RTgill-W1 cell line following exposures to high cell densities of lysed cells (>100,000 cells mL−1). Fatty acid profiles of a cultured strain showed elevated concentrations of potentially ichthyotoxic, long-chain polyunsaturated fatty acids (PUFAs) (69.7% ± 1.8%)- stearidonic (SDA, 18:4ω3–28.9%), and docosahexaenoic acid (DHA, 22:6ω3–22.3%), suggesting that lipid peroxidation may help to explain the mortalities, though superoxide production by Pseudochattonella was low (< 0.21 ± 0.19 pmol O2− cell−1 h−1). It therefore remains unknown what the mechanisms of salmon mortality were during the Pseudochattonella bloom. Multiple mitigation strategies were used by salmon farmers during the event, with only delayed seeding of juvenile fish into the cages and towing of cages to sanctuary sites being effective. Airlift pumping, used effectively against other fish-killing HABs in the US and Canada was not effective, perhaps because it brought subsurface layers of Pseudochattonella to the surface, or and it also may have lysed the fragile cells, rendering them more lethal. The present study highlights knowledge gaps and inefficiency of contingency plans by the fish farming industry to overcome future fish-killing algal blooms under future climate change scenarios. The use of new technologies based on molecular methods for species detection, good farm practices by fish farms, and possible mitigation strategies are discussed.

172 Enteric methane emissions from pregnant beef heifers as affected by multiple mitigation strategies

Abstract This study was conducted to determine if enteric methane (CH4) emissions from pregnant beef heifers could be reduced by using multiple dietary mitigation strategies. The trial was designed as a 4 x 4 Latin square consisting of a 21-d adaptation phase followed by a 21-d data collection phase. Forty Aberdeen Angus cross pregnant beef heifers were randomly assigned to one of the four dietary treatments (n = 10): i) low protein grass hay (L; 6.1% CP; 1.9% fat); ii) adequate protein grass hay (AD; 10.8% CP; 1.9% fat); iii) AD supplemented with sunflower screenings (ADSS; 9.8% CP; 5.6% fat); and iv) above adequate protein legume grass mix hay (AAD; 12.8% CP; 1.7% fat). Total dry matter intake (DMI) was 32%, 27% and 39% greater (P &amp;lt; 0.0001) for AD, ADSS and AAD respectively, relative to the L diet (6.5 kg d-1). Average daily gain (ADG; kg d-1) was influenced by dietary treatment (P &amp;lt; 0.0001), as heifers offered L, AD, ADSS and AAD diets gained 0 ± 0.2, 0.6 ± 0.2, 0.5 ± 0.2 and 0.7 ± 0.2 kg d-1, respectively. Enteric CH4 emissions (L d-1), were influenced by dietary treatment (P &amp;lt; 0.0001) with 184 ± 18.9, 214 ± 19.0, 204 ± 19.1 and 232 ± 19.1 L d-1 for heifers offered L, AD, ADSS and AAD diets, respectively. Further, heifers offered AD, ADSS and AAD diets emitted 19%, 22% and 14% less (P=0.03) enteric CH4 (% GEI) relative to diet L, respectively. This study demonstrates that supplementation to meet nutrient requirements for protein or increasing the fat content of forage-based diets using low-cost by-products such as sunflower screenings can decrease enteric CH4 emissions without adversely impacting total DMI and ADG.

PSII-22 Trends in Mycotoxin Contamination in United States Corn

Abstract Mycotoxins are harmful secondary fungal metabolites and are of key concern to food and feed safety globally. These toxins are detrimental to animal health and can compromise animal performance even at low levels. Classic signs such as decreased feed intake and vomiting used as indicators for exposure overlook other costs of mycotoxicosis, including increasing the frequency and severity of disease via immune suppression, inciting inflammation, and modulating the gastrointestinal environment. This survey examines initial samples of the 2019 crop with previous year trends. New crop corn samples were submitted from September 2019 and consisted of corn (46%), corn silage (50%), and corn byproduct (4%). Samples were analyzed utilizing the liquid chromatography and tandem mass spectrometry (LC-MS/MS) method for six major mycotoxin groups: aflatoxins (Afla), type A trichothecenes (A-Trich), type B trichothecenes (B-Trich), fumonisins (FUM), zearalenone (ZEN), and ochratoxin-A (OTA). Data are presented for major mycotoxin classes in Table 1. Fewer samples are available thus far compared to the fall of 2018 (50 samples in 2019 vs. 135 samples in 2018), thus risk profile of this crop year is likely to change as the sample pool expands. Co-occurrence (≥ 2 mycotoxins) has decreased compared to 2018. The prevalence of B-Trich decreased compared with previous years, but levels are similar to 2018. Prevalence and levels of ZEN decreased from 2018, and are similar to 2017, while FUM is similar in prevalence to 2018, but average ppb numerically increased. As of yet, no Alfa has been detected; however, corn stored with higher moisture content has increased the risk for storage toxins. Mycotoxin risk of this harvest season is still coming into focus as harvest delays have affected sample submission. Due to continued risk of multi-mycotoxin contamination, multiple mitigation strategies are needed beyond just adsorption, including biotransformation, support of the immune system and liver function.

Boarding of Critically Ill Patients in the Emergency Department.

Emergency department boarding is the practice of caring for admitted patients in the emergency department after hospital admission, and boarding has been a growing problem in the United States. Boarding of the critically ill has achieved specific attention because of its association with poor clinical outcomes. Accordingly, the Society of Critical Care Medicine and the American College of Emergency Physicians convened a Task Force to understand the implications of emergency department boarding of the critically ill. The objective of this article is to review the U.S. literature on (1) the frequency of emergency department boarding among the critically ill, (2) the outcomes associated with critical care patient boarding, and (3) local strategies developed to mitigate the impact of emergency department critical care boarding on patient outcomes. Review article. Emergency department-based boarding of the critically ill patient is common, but no nationally representative frequency estimates has been reported. Boarding literature is limited by variation in the definitions used for boarding and variation in the facilities studied (boarding ranges from 2% to 88% of ICU admissions). Prolonged boarding in the emergency department has been associated with longer duration of mechanical ventilation, longer ICU and hospital length of stay, and higher mortality. Health systems have developed multiple mitigation strategies to address emergency department boarding of critically ill patients, including emergency department-based interventions, hospital-based interventions, and emergency department-based resuscitation care units. Emergency department boarding of critically ill patients was common and was associated with worse clinical outcomes. Health systems have generated a number of strategies to mitigate these effects. A definition for emergency department boarding is proposed. Future work should establish formal criteria for analysis and benchmarking of emergency department-based boarding overall, with subsequent efforts focused on developing and reporting innovative strategies that improve clinical outcomes of critically ill patients boarded in the emergency department.