223 research outputs found

    Soil Microbial Community Dynamics in Response to Prescribed Extreme Fires Following \u3ci\u3eJuniperus virginiana\u3c/i\u3e Invasion in the Loess Canyons of Nebraska

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    In Nebraska and other regions of the Great Plains, the conifer Juniperus virginiana (eastern redcedar) is converting grasslands to dense woodlands. This is driven by the interacting drivers of fire suppression, altered grazing regimes, climate change and other anthropogenic factors, impacting the provisioning of ecosystem services. This vegetation state transition modifies water resource regulation and biogeochemical cycles leading to altered edaphic properties including soil microbial community composition. To restore these grasslands and control J. virginiana spread, prescribed extreme burns are implemented as a management tool through local prescribed burn associations. We hypothesized that the alternative state transition to dense J. virginiana woodlands leads to a corresponding state transition below-ground that persists post-extreme burn and may facilitate J. virginiana re-establishment. To address this hypothesis, paired grasslands and J. virginiana woodlands in the Loess Canyons of Central Nebraska were subjected to one prescribed extreme burn between 2005 and 2019 to provide a natural burn chronosequence. We quantified J. virginiana re-establishment, soil chemistry, soil microbial biomass and microbial community composition in these paired sites across the chronosequence. Our results partially supported our hypothesis where differences in edaphic variables between J. virginiana sites and grassland sites observed post-burn were largely temporary; however, differences in soil magnesium and microbial community composition were more persistent (\u3e 14 years post-burn). Soil magnesium values were significantly higher in the J. virginiana sites both pre-burn and post-burn across the 14 year chronosequence. Microbial communities were also distinct between J. virginiana and grassland sites pre-burn and across the burn chronosequence. Rapid recovery and/or persistence of specific edaphic factors and soil microbial communities in J. virginiana woodlands post-burn may facilitate early J. virginiana re-establishment. Restoration of historical fire intervals is needed to prevent long term changes to soil function that may facilitate J. virginiana re-establishment. Advisors: Tala Awada and Rhae A. Drijbe

    Revolutionising Fish Ageing: Using Near Infrared Spectroscopy to Age Fish

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    The project aimed to evaluate the innovative application of NIRS as a reliable, repeatable, and cost-effective method of ageing fish, using otoliths of Barramundi and Snapper as study species. Specific research questions included assessing how geographic and seasonal variation in otoliths affects NIRS predictive models of fish age, as well as how the NIR spectra of otoliths change in the short-term (i.e., <12 months) and long-term (i.e., historical otolith collections) and what effect this has on the predictive ability of NIRS models. The cost-effectiveness of using NIRS to supplement standard fish ageing methods was also evaluated using a hypothetical case study of Barramundi

    Calretinin is a novel candidate marker for adverse ovarian effects of early life exposure to mixtures of endocrine disruptors in the rat

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    Open Access via Springer Compact Acknowledgements This work was funded by the Ministry of Environment and Food of Denmark, and by a grant from the European Commission 7th Framework Program CONTAMED (Contaminant mixtures and human reproductive health-novel strategies for health impact and risk assessment of endocrine disrupters, grant agreement no.: 215202), as well as the Medical Research Council (UK) (MR/L010011/1 to PAF) and the EU Horizon 2020 project FREIA (Grant Number 825100). We would like to thank Heidi Letting, the Animal facilities at DTU food, and the University of Aberdeen Proteomics Core Facility for their support and assistance in this work.Peer reviewedPublisher PD

    Heterogeneity

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    This entry discusses heterogeneity in the context of ecological landscapes and how the heterogeneity impacts the resilience of the system. Heterogeneity is closely linked to the scale of measurement, both spatially and temporally. We will walk through a simple example that highlights how the scale of observation can impact the heterogeneity of the system. The differences between functional and measured heterogeneity will also be explained. Finally, heterogeneity will be discussed in the context of its utility to management and how it can be used to understand the resilience of agro-ecosystems. Overview - What Will You Learn In This Lesson? This lesson discusses what heterogeneity is and how it relates to understanding and interpreting natural phenomena. Objectives This lesson covers the concept of heterogeneity. At the end of this module you should be able to: Define heterogeneity in the context of environmental management Explain the relationship between heterogeneity and ecological resilience Differentiate between functional and measured heterogeneity in ecology Understand the importance and usefulness of heterogeneity in resource management Modules Lesson home Overview and Objectives Introduction - What Is Heterogeneity? Measures of Heterogeneity Heterogeneity in Management - How Does This Concept Impact Real-World Management? Example - Heterogeneity of Zoning in Cities Summary - What Did We Learn? Quiz Questions References and Further Reading Glossar

    Transcription factor network downstream of protease activated receptors (PARs) modulating mouse bladder inflammation

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    <p>Abstract</p> <p>Background</p> <p>All four PARs are present in the urinary bladder, and their expression is altered during inflammation. In order to search for therapeutic targets other than the receptors themselves, we set forth to determine TFs downstream of PAR activation in the C57BL/6 urinary bladders.</p> <p>Methods</p> <p>For this purpose, we used a protein/DNA combo array containing 345 different TF consensus sequences. Next, the TF selected was validated by EMSA and IHC. As mast cells seem to play a fundamental role in bladder inflammation, we determined whether c-kit receptor deficient (Kit<sup>w</sup>/Kit<sup>w-v</sup>) mice have an abrogated response to PAR stimulation. Finally, TFEB antibody was used for CHIP/Q-PCR assay and revealed up-regulation of genes known to be downstream of TFEB.</p> <p>Results</p> <p>TFEB, a member of the MiTF family of basic helix-loop-helix leucine zipper, was the only TF commonly up-regulated by all PAR-APs. IHC results confirm a correlation between inflammation and TFEB expression in C57BL/6 mice. In contrast, Kit<sup>w</sup>/Kit<sup>w-v </sup>mice did not exhibit inflammation in response to PAR activation. EMSA results confirmed the increased TFEB binding activity in C57BL/6 but not in Kit<sup>w</sup>/Kit<sup>w-v </sup>mice.</p> <p>Conclusion</p> <p>This is the first report describing the increased expression of TFEB in bladder inflammation in response to PAR activation. As TFEB belongs to a family of TFs essential for mast cell survival, our findings suggest that this molecule may influence the participation of mast cells in PAR-mediated inflammation and that targeting TFEB/MiTF activity may be a novel approach for the treatment of bladder inflammatory disorders.</p

    Fourteen propositions for resilience, fourteen years later

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    In 2006, Walker et al. published an article titled, “A Handful of Heuristics and Some Propositions for Understanding Resilience in Social-ecological Systems.” The article was incorporated into the Ecology and Society special feature, Exploring Resilience in Social-Ecological Systems. Walker et al. identified five heuristics and posed 14 propositions for understanding resilience in social-ecological systems. At the time, the authors hoped the paper would promote experimentation, critique, and application of these ideas in resilience and social-ecological systems research. To determine the extent to which these propositions have achieved the authors’ hopes, we reviewed the scientific literature on socialecological systems since the article was published. Using Scopus, we identified 627 articles that cited the Walker et al. article. We then identified and assessed the articles relative to each proposition. In addition, we conducted a more general Scopus review for articles that did not cite the Walker et al. article specifically but incorporated a proposition’s concepts. Overall, articles often cite Walker et al. as a reference for a definition of a heuristic or ecological resilience generally and not to reference a specific proposition. Nonetheless, every proposition was at least mentioned in the literature and used to advance resilience scholarship on social-ecological systems. Eleven propositions were tested by multiple articles through application of case studies or other research, and 7 of the 11 propositions were substantially discussed and advanced. Finally, three propositions were heavily critiqued either as concepts in resilience literature or in their application

    Vehicle Design Data Format and Process for a Complete TARIS and OLTARIS Radiation Analysis for Designers and Engineers

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    Protecting astronauts from space radiation is a complex task when it comes to modeling and simulation. This document shows what information is needed from a spacecraft designer using CAD (Computer-Assisted Design) at each phase of the design to enable the engineers to evaluate the design phase against space radiation limits to determine the suitability of the design for space flight. The current personal exposure limits are listed in NASA STD-3001. A proxy to determine the REID (Radiation Exposure Induced Death) in NASA STD-3001 is the whole body effective dose equivalent (E or effective dose). For short-term tissue effects, organ-averaged gray equivalent (G (sub T)) is used. The TARIS (Tool for the Assessment of Radiation In Space - for LaRC (Langley Research Center) engineers) and OLTARIS (On-Line TARIS) - for designers) systems are used to generate these response functions. The E can use ICRP60 or NASA Q-values. A possible space radiation design basis environment for short-term tissue effects is described and used in all analyses. A single space vehicle was designed with three astronaut configurations and two of those configurations were used in a storm shelter thickness perturbation analysis. Conversion of the data from the CAD model to input necessary for TARIS and OLTARIS is also discussed in detail with relevant examples

    Characterizing uncertainty of the hydrologic impacts of climate change

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    The high climate sensitivity of hydrologic systems, the importance of those systems to society, and the imprecise nature of future climate projections all motivate interest in characterizing uncertainty in the hydrologic impacts of climate change. We discuss recent research that exposes important sources of uncertainty that are commonly neglected by the water management community, especially, uncertainties associated with internal climate system variability, and hydrologic modeling. We also discuss research exposing several issues with widely used climate downscaling methods. We propose that progress can be made following parallel paths: first, by explicitly characterizing the uncertainties throughout the modeling process (rather than using an ad hoc “ensemble of opportunity”) and second, by reducing uncertainties through developing criteria for excluding poor methods/models, as well as with targeted research to improve modeling capabilities. We argue that such research to reveal, reduce, and represent uncertainties is essential to establish a defensible range of quantitative hydrologic storylines of climate change impacts
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