1,633 research outputs found

    MANAGING MANURE TO IMPROVE AIR AND WATER QUALITY

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    Animal waste from confined animal feeding operations is a potential source of air and water quality degradation from evaporation of gases, runoff to surface water, and leaching to ground water. This report assesses the potential economic and environmental tradeoffs between water quality policies and air quality policies that require the animal agriculture sector to take potentially costly measures to abate pollution. A farm-level analysis of hog farms estimates the economic and environmental tradeoffs that occur when policies are designed to address pollutant flows to one environmental medium without considering flows to another medium. A national analysis addresses the broader impacts of coordinated (water and air) policies, including long-term structural adjustments and welfare impacts on both producers and consumers. The report also analyzes the potential implications of adding air quality regulations to existing Clean Water Act regulations in the Chesapeake Bay watershed, where a limited land base increases producers' costs of meeting manure management requirements.animal waste, nitrogen, ammonia, water quality, nutrient management plan, manure management costs, price and quantity adjustments, CAFO, Environmental Economics and Policy, Livestock Production/Industries,

    B841: Maine\u27s Household Garbage

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    The objective of this report is to present findings from an analysis of Maine\u27s nonbulky domestic waste stream.https://digitalcommons.library.umaine.edu/aes_bulletin/1009/thumbnail.jp

    Making It Easier To Be Green: A Single Case Demonstration of the Effects of Computer Defaults To Conserve Energy in a University Computer Lab

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    This is the publisher's version, also available electronically from http://online.liebertpub.com/doi/abs/10.1089/SUS.2013.9827Educational buildings and university campuses represent some of the most computer-dense settings in the United States. Unfortunately, the administrators and users in these settings often lack proper energy saving strategies, resulting in excessive energy waste. Research in behavioral economics has reliably shown that effort is an inhibitory factor in changing a variety of behaviors. That is, humans have a tendency to choose the option that requires the least amount of effort, regardless of whether that option is the best one. Thus, it might be inferred that interventions requiring greater effort for computer users to conserve energy are unlikely to be effective. This study highlights a successful cost-cutting application of default energy savings settings in a campus computer-testing laboratory. Default settings applied by the research team did not require effort on the part of users and resulted in computers powering-down after a relatively short period of inactivity. A cost analysis revealed modest fiscal and electricity savings among the small number of computers included in the study. However, extrapolating these modest savings across the many hundreds of work stations typically found on university campuses suggests a substantial savings would result from the adoption of the intervention described herein. Implications for practice and future research are discussed

    MANURE MANAGEMENT FOR WATER QUALITY COSTS TO ANIMAL FEEDING OPERATIONS OF APPLYING MANURE NUTRIENTS TO LAND

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    Nutrients from livestock and poultry manure are key sources of water pollution. Ever-growing numbers of animals per farm and per acre have increased the risk of water pollution. New Clean Water Act regulations compel the largest confined animal producers to meet nutrient application standards when applying manure to the land, and USDA encourages all animal feeding operations to do the same. The additional costs for managing manure (such as hauling manure off the farm) have implications for feedgrain producers and consumers as well. This report's farm-level analysis examines on-farm technical choice and producer costs across major U.S. production areas for hauling manure to the minimum amount of land needed to assimilate manure nutrients. A regional analysis then focuses on off-farm competition for land to spread surplus manure, using the Chesapeake Bay region as a case study. Finally, a sectorwide analysis addresses potential long-term structural adjustments at the national level and ultimate costs to consumers and producers.manure management costs, price and quantity adjustments, water quality, animal waste, manure nutrients, excess nutrients, confined animals, CAFO, manure nitrogen, manure phosphorus, manure use, assimilative capacity, nutrient management plan, Environmental Economics and Policy, Livestock Production/Industries,

    Evidence for Height and Immune Function Trade-offs Among Preadolescents in a High Pathogen Population

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    Background In an energy-limited environment, caloric investments in one characteristic should trade-off with investments in other characteristics. In high pathogen ecologies, biasing energy allocation towards immune function over growth would be predicted, given strong selective pressures against early-life mortality. Methodology In the present study, we use flow cytometry to examine trade-offs between adaptive immune function (T cell subsets, B cells), innate immune function (natural killer cells), adaptive to innate ratio and height-for-age z scores (HAZ) among young children (N = 344; aged 2 months–8 years) in the Bolivian Amazon, using maternal BMI and child weight-for-height z scores (WHZ) as proxies for energetic status. Results Markers of adaptive immune function negatively associate with child HAZ, a pattern most significant in preadolescents (3+ years). In children under three, maternal BMI appears to buffer immune and HAZ associations, while child energetic status (WHZ) moderates relationships in an unexpected direction: HAZ and immune associations are greater in preadolescents with higher WHZ. Children with low WHZ maintain similar levels of adaptive immune function, but are shorter compared to high WHZ peers. Conclusions Reduced investment in growth in favor of immunity may be necessary for survival in high pathogen contexts, even under energetic constraints. Further, genetic and environmental factors are important considerations for understanding variation in height within this population. These findings prompt consideration of whether there may be a threshold of investment into adaptive immunity required for survival in high pathogen environments, and thus question the universal relevance of height as a marker of health. Lay Summary Adaptive immune function is negatively associated with child height in this high pathogen environment. Further, low weight-for-height children are shorter but maintain similar immune levels. Findings question the relevance of height as a universal health marker, given that costs and benefits of height versus immunity may be calibrated to local ecology

    Re-examination of the I-5 dust storm

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    The infamous dust storm over the thanksgiving holiday of 1991 that led to loss of life from numerous automobile accidents on Interstate 5 (I-5) has been re-examined. Pauley et al. (1996) conducted an earlier investigation of this dust storm following the tenets of Danielsen's paradigm—a paradigm that links the tropopause fold phenomenon and a balanced thermally indirect circulation about the upper level jet stream. However, a cursory examination of mesoscale structures in the storm from the North American Regional Reanalysis (NARR) indicated evidence of a low-level unbalanced thermally direct circulation that demanded further investigation using a high-resolution Weather Research and Forecasting (WRF) model simulation. Principal results from the present study follow: (1) Although the model simulation showed evidence of a weak indirect circulation in the upper troposphere in support of the Danielsen's paradigm, the dynamic control of the storm stemmed from the lower tropospheric mesoscale response to geostrophic imbalance. (2) A lower tropospheric direct circulation led to mass/temperature adjustments that were confirmed by upper air observations at locations in proximity to the accident site, and (3) boundary layer deepening and destabilization due to these mesoscale processes pinpointed the timing and location of the dust storm. Although the present study does not underestimate the value of analyses that focus on the larger/synoptic scales of motion, it does bring to light the value of investigation that makes use of the mesoscale resources in order to clarify synoptic-mesoscale interactions

    Nonoperative management of tibial stress fractures result in higher return to sport rates despite increased failure versus operative management: A systematic review

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    PURPOSE: To compare return to sport (RTS) rates and complications after nonoperative versus operative management of tibial stress fractures. METHODS: A literature search was conducted per the 2020 Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines using EMBASE, PubMed, and Scopus computerized data from database inception to February 2023. Studies evaluating RTS sport rates and complications after nonoperative or operative management of tibial stress fractures were included. Failure was defined as defined by persistent stress fracture line seen on radiographic imaging. Study quality was assessed using the Modified Coleman Methodology Score. RESULTS: Twenty-two studies consisting of 341 patients were identified. The overall RTS rate ranged from 91.2% to 100% in the nonoperative group and 75.5% to 100% in the operative group. Failures rates ranged from 0% to 25% in the nonoperative groups and 0% to 6% in the operative group. Reoperations were reported in 0% to 6.1% of patients in the operative group, whereas 0% to 12.5% of patients initially managed nonoperatively eventually required operative treatment. CONCLUSIONS: Patients can expect high RTS rates after appropriate nonoperative and operative management of tibial stress fractures. Treatment failure rates were greater in patients undergoing nonoperative management, with up to 12.5% initially treated nonoperatively later undergoing operative treatment. LEVEL OF EVIDENCE: Level IV; Systematic Review of level I-IV studies

    High Nucleosome Occupancy Is Encoded at Human Regulatory Sequences

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    Active eukaryotic regulatory sites are characterized by open chromatin, and yeast promoters and transcription factor binding sites (TFBSs) typically have low intrinsic nucleosome occupancy. Here, we show that in contrast to yeast, DNA at human promoters, enhancers, and TFBSs generally encodes high intrinsic nucleosome occupancy. In most cases we examined, these elements also have high experimentally measured nucleosome occupancy in vivo. These regions typically have high G+C content, which correlates positively with intrinsic nucleosome occupancy, and are depleted for nucleosome-excluding poly-A sequences. We propose that high nucleosome preference is directly encoded at regulatory sequences in the human genome to restrict access to regulatory information that will ultimately be utilized in only a subset of differentiated cells
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