1,219 research outputs found
Giving credit to reforestation for water quality benefits.
While there is a general belief that reforesting marginal, often unprofitable, croplands can result in water quality benefits, to date there have been very few studies that have attempted to quantify the magnitude of the reductions in nutrient (N and P) and sediment export. In order to determine the magnitude of a credit for water quality trading, there is a need to develop quantitative approaches to estimate the benefits from forest planting in terms of load reductions. Here we first evaluate the availability of marginal croplands (i.e. those with low infiltration capacity and high slopes) within a large section of the Ohio River Basin (ORB) to assess the magnitude of the land that could be reforested. Next, we employ the Nutrient Tracking Tool (NTT) to study the reduction in N, P and sediment losses from converting corn or corn/soy rotations to forested lands, first in a case study and then for a large region within the ORB. We find that after reforestation, N losses can decrease by 40 to 80 kg/ha-yr (95-97% reduction), while P losses decrease by 1 to 4 kg/ha-yr (96-99% reduction). There is a significant influence of local conditions (soils, previous crop management practices, meteorology), which can be considered with NTT and must be taken into consideration for specific projects. There is also considerable interannual and monthly variability, which highlights the need to take the longer view into account in nutrient credit considerations for water quality trading, as well as in monitoring programs. Overall, there is the potential for avoiding 60 million kg N and 2 million kg P from reaching the streams and rivers of the northern ORB as a result of conversion of marginal farmland to tree planting, which is on the order of 12% decrease for TN and 5% for TP, for the entire basin. Accounting for attenuation, this represents a significant fraction of the goal of the USEPA Gulf of Mexico Hypoxia Task Force to reduce TN and TP reaching the dead zone in the Gulf of Mexico, the second largest dead zone in the world. More broadly, the potential for targeted forest planting to reduce nutrient loading demonstrated in this study suggests further consideration of this approach for managing water quality in waterways throughout the world. The study was conducted using computational models and there is a need to evaluate the results with empirical observations
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Are geometric morphometric analyses replicable? Evaluating landmark measurement error and its impact on extant and fossil Microtus classification.
Geometric morphometric analyses are frequently employed to quantify biological shape and shape variation. Despite the popularity of this technique, quantification of measurement error in geometric morphometric datasets and its impact on statistical results is seldom assessed in the literature. Here, we evaluate error on 2D landmark coordinate configurations of the lower first molar of five North American Microtus (vole) species. We acquired data from the same specimens several times to quantify error from four data acquisition sources: specimen presentation, imaging devices, interobserver variation, and intraobserver variation. We then evaluated the impact of those errors on linear discriminant analysis-based classifications of the five species using recent specimens of known species affinity and fossil specimens of unknown species affinity. Results indicate that data acquisition error can be substantial, sometimes explaining >30% of the total variation among datasets. Comparisons of datasets digitized by different individuals exhibit the greatest discrepancies in landmark precision, and comparison of datasets photographed from different presentation angles yields the greatest discrepancies in species classification results. All error sources impact statistical classification to some extent. For example, no two landmark dataset replicates exhibit the same predicted group memberships of recent or fossil specimens. Our findings emphasize the need to mitigate error as much as possible during geometric morphometric data collection. Though the impact of measurement error on statistical fidelity is likely analysis-specific, we recommend that all geometric morphometric studies standardize specimen imaging equipment, specimen presentations (if analyses are 2D), and landmark digitizers to reduce error and subsequent analytical misinterpretations
Intent to Continue Growing Switchgrass as a Dedicated Energy Crop: A Case Study of Switchgrass Producers in East Tennessee
Efforts to reduce the United States’ dependence on foreign petroleum encourage the production of fuels from bioenergy crops. Recent energy mandates have therefore “opened doors” for alternative feedstock sources for ethanol production. Switchgrass is a candidate feedstock. Under the University of Tennessee’s Biofuels Initiative, the University of Tennessee, partnering with DuPont-Danisco Cellulosic Ethanol LLC, contracted for the production of switchgrass with local farmers to guarantee biomass feedstock supply for an ethanol conversion research facility. This study used methods borrowed from the social psychology literature in combination with economic theory to analyze factors influencing switchgrass farmers’ intentions to continue growing switchgrass after contracts with the granting agent expired. Understanding what motivates producers to make long term commitments to switchgrass production as an energy crop may be important information for private investors who will rely on a fixed supply of switchgrass.
A probit model was used to determine the factors affecting producers’ intentions to continue producing switchgrass after their contract expires. Results suggest that community perceptions about the production of switchgrass as a dedicated energy crop may have an important impact on farmers’ intentions to make a long-term commitment to produce switchgrass. Therefore, educating and involving community and extension personnel may have a positive impact on farmers’ decisions to make long-term commitments to grow switchgrass as a dedicated energy crop
Development of a best practices manual for the U.S. Department of Energy\u27s Wind for Schools Project
The Development of a Best Practices Manual for the U.S. Department of Energy’s Wind for Schools Project is an effort to provide the necessary research and data to make the completion of a Best Practices Manual possible. The Best Practices Manual will be used to help with the future development of Wind for Schools Projects nationally. The Wind for Schools Project was developed in 2005; currently 11 states are actively participating. As the Wind for Schools Project developed, various approaches and techniques were used to meet the goals of the program. A Best Practices Manual will serve as a repository of successful strategies and approaches employed by the program. The development of the Best Practices Manual focused on the research needed to understand the Wind for Schools Project; this included background on the U.S. Education System, a comprehensive study of the Wind for Schools Structure, a study of each 11 state programs, defining a best practice, the development and dispersion of a survey for the Wind for Schools Facilitators and Wind Application Center Directors, and a final outline for the Best Practices Manual. This effort is an attempt to pull together all the necessary research for the Best Practices Manual; which will in turn present generally-accepted, informally-standardized methods and techniques that have been developed to accomplish the three main goals of Wind for Schools
Marshall University Music Department Presents the Marshall University Aftrican Drumming & Dance Ensemble, Steven Hall, conductor, Jessica Fox, assistant conductor
https://mds.marshall.edu/music_perf/1643/thumbnail.jp
Animal Behavior: Fly Flight Moves Forward
SummaryA new study has resolved the paradox of how flies maintain reflexive aversion to your approaching swatter, whilst tolerating similar visual signals during normal forward flight
Monitoring, Creeping, or Surveillance? A Synthesis of Online Social Information Seeking Concepts
Affordances of Internet sites and Internet-based applications make personal information about romantic partners, friends, family members, and strangers easy to obtain. People use various techniques to find information about others, capitalizing on online affordances by using search engines to find relevant websites and databases; scouring the target’s social media or social networking site presence; accessing information about the target via their links or network association with others on social media; or asking questions or crowdsourcing information through online channels. Researchers have coined an assortment of terms to describe online social information seeking behaviors, such as interpersonal electronic surveillance, social surveillance, monitoring, patient-targeted Googling, cybervetting, websleuthing, human flesh search, lateral surveillance, Facebook surveillance, and Facebook stalking. Although considerable research has examined these behaviors, there has been little effort to clarify the concepts themselves. As a result, the literature is currently full of inconsistent and overlapping conceptualizations. To synthesize these concepts for future research, this review examines 73 online social information seeking concepts extracted from 186 articles. Specifically, the concepts are reviewed in light of their scope; the information seeker or target of information seeking (e.g., romantic partners, parents, children, employees, criminals); motives for information seeking (e.g., uncertainty, threat, curiosity); and the intensity of the behavior. Recommendations are provided for future research, such as employing clear conceptualizations and incorporating affordances. Finally, we offer a decision tree that researchers can use to help select appropriate terms to use in their work moving forward
Transcriptome meta-analysis reveals a central role for sex steroids in the degeneration of hippocampal neurons in Alzheimer’s disease
BACKGROUND: Alzheimer’s disease is the most prevalent form of dementia. While a number of transcriptomic studies have been performed on the brains of Alzheimer’s specimens, no clear picture has emerged on the basis of neuronal transcriptional alterations linked to the disease. Therefore we performed a meta-analysis of studies comparing hippocampal neurons in Alzheimer’s disease to controls. RESULTS: Homeostatic processes, encompassing control of gene expression, apoptosis, and protein synthesis, were identified as disrupted during Alzheimer’s disease. Focusing on the genes carrying out these functions, a protein-protein interaction network was produced for graph theory and cluster exploration. This approach identified the androgen and estrogen receptors as key components and regulators of the disrupted homeostatic processes. CONCLUSIONS: Our systems biology approach was able to identify the importance of the androgen and estrogen receptors in not only homeostatic cellular processes but also the role of other highly central genes in Alzheimer’s neuronal dysfunction. This is important due to the controversies and current work concerning hormone replacement therapy in postmenopausal women, and possibly men, as preventative approaches to ward off this neurodegenerative disorder
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