1,870 research outputs found

    Characterization of Legacy Sediment variations in accretion and carbon dynamics following dam removal in a recently restored tidal freshwater wetland

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    Damming disrupts the natural flow of sediment to adjoining water bodies resulting in the accumulation of Legacy Sediments (LS). While the impact of LS inputs has been well investigated in lotic Mid-Atlantic piedmont stream restorations, (i.e. milldam removal 1,2,3,4,5,), there have been few studies investigating LS following dam removal in low-gradient coastal plain streams. The objectives of this study were to quantify spatial and temporal variations of LS characteristics in a low-gradient tidal stream restoration within the lower James River watershed. Secondary objectives were to assess the current temporal and spatial variability in sediment deposition within the recently restored Kimages Creek wetlands and adjacent, unaltered wetlands of Harris Creek to investigate current sedimentation processes in a restoration setting

    A Baseline Study of Edaphic Characteristics, Vegetation Structure, and Recruitment of Native Baldcypress (Taxodium distichum (L). Rich. Var. distichum) in the Newly Restored Wetland of the VCU Rice Rivers Center

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    In theory, the ideal of ecological restoration is to reestablish a completely functioning ecosystem, however restoration success is often elusive (Stanturf et al. 2001). There is a significant gap in the current research on the impacts of restoration management of restored wetlands on ecosystem functions, especially biogeochemical cycling (Bernal & Mitsch 2013). Furthermore, there are many questions about management techniques when it comes to ecological engineering versus self-design (Bernal & Mitsch, 2013). However, we do know that it is critical to understand the species’ life history, habitat template, and spatio temporal scope when attempting to re-establish populations (Lake et al. 2007). Since resources for conservation and restoration of wetlands are limiting there is a great need to fully understand both the biogeochemical cycling and life history strategies of recruitment and population expansion of target wetland species in restored wetlands in order to have the best chance of restoration success (Mitsch & Gosselink 2007)

    Understanding cellular function and disease with comparative pathway analysis

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    Pathway analysis is important in interpreting the functional implications of high-throughput experimental results, but robust comparison across platforms and species is problematic. A new approach, Pathprinting, provides a cross-platform, cross-species comparative analysis of pathway expression signatures. This method calculates pathway-level statistics from gene expression across nearly 180,000 microarrays in the Gene Expression Omnibus. Pathprinting can accurately retrieve phenotypically similar samples and identify sets of human and mouse genes that are prognostic in cancer

    UPPS-P Model Impulsivity and Marijuana Use Behaviors in Adolescents: A Meta-Analysis

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    Background Impulsivity is often included as a risk factor in models of adolescent marijuana use behaviors; however, the magnitude of the association between impulsivity and marijuana use behaviors is variable across studies. The present study reviewed existent literature to 1) quantify the relationship between separable impulsivity-related traits and both marijuana use and negative marijuana consequences and 2) quantify the size of the effect of gender on these relationships. Method Thirty-eight studies (41 independent samples) were meta-analyzed using a random effects model to examine the relationship between impulsivity traits and marijuana use behaviors. Results Marijuana use was significantly related to all impulsivity-related traits except lack of perseverance (r’s ranging from 0.13–0.23, p’s < 0.01). Negative marijuana consequences were only significantly related to sensation seeking, lack of planning, and positive urgency (r’s ranging from 0.37–0.39, p’s < 0.01). Effects were small for marijuana use, but medium for negative marijuana consequences. Gender was not a significant moderator of any relationships. Conclusions Impulsivity-related traits had more robust relationships with negative marijuana consequences than marijuana use, suggesting impulsivity-related traits are important in differentiating adolescents most likely to experience negative consequences from marijuana use. Few relationships examined gender and many of the impulsivity-related traits, other than sensation seeking. Data and trends suggest a more multi-dimensional approach to marijuana use and consequences is warranted

    Automatic, context-specific generation of Gene Ontology slims

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    Background: The use of ontologies to control vocabulary and structure annotation has added value to genome-scale data, and contributed to the capture and re-use of knowledge across research domains. Gene Ontology (GO) is widely used to capture detailed expert knowledge in genomic-scale datasets and as a consequence has grown to contain many terms, making it unwieldy for many applications. To increase its ease of manipulation and efficiency of use, subsets called GO slims are often created by collapsing terms upward into more general, high-level terms relevant to a particular context. Creation of a GO slim currently requires manipulation and editing of GO by an expert (or community) familiar with both the ontology and the biological context. Decisions about which terms to include are necessarily subjective, and the creation process itself and subsequent curation are time-consuming and largely manual

    Characterization of Current and Historical Variations in Sediment Accretion and Carbon Dynamics at the Rice Rivers Center Kimages Creek Wetland Restoration

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    Current research of freshwater wetland soils have assessed and reported smaller stocks of soil organic carbon in restored wetlands compared to reference natural wetlands. However, a majority of these studies focus on sites restored from agricultural draining of non-tidal depressional wetlands,whereas carbon and accretion dynamics in tidal freshwater wetlands restored via dam removal is poorly understood. The U.S. Army Corps of Engineers estimates over 80,000 dams greater than 6 feet and tens of thousands of smaller dams pepper the U.S., of which the majority are unsafe, old or no longer serve their intended purpose. Damming disrupts the natural flow of sediment to adjoining water bodies resulting in the accumulation of what are commonly referred to as Legacy Sediments (LS). These sediments have the ability to alter the biology, hydrology, geomorphology, and biogeochemistry of their river corridors and adjacent riparian ecosystems. While the effect of these sediment inputs on ecosystem function has been well investigated in non-tidal regions, particularly in the form of milldam removal, there has been little-to-no inquiry on how LS exist within and affect tidal wetlands and their biotic and abiotic processes. The objectives of this study are to uantify the current temporal and spatial variation in sediment deposition and soil carbon dynamics within KC and Harris Creek (HC) wetlands via sediment collection tiles (SCTs); assess the differences in LS characteristics along the tidal to non-tidal gradient and between different depositional areas through soil core sampling and radiocarbon dating; and, compare carbon sequestration and sediment accretion rates between the two historical environments: the pre-impoundment forested freshwater wetland & the Lake Charles environment (LS)

    Protein-protein interaction as a predictor of subcellular location

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    Background: Many biological processes are mediated by dynamic interactions between and among proteins. In order to interact, two proteins must co-occur spatially and temporally. As protein-protein interactions (PPIs) and subcellular location (SCL) are discovered via separate empirical approaches, PPI and SCL annotations are independent and might complement each other in helping us to understand the role of individual proteins in cellular networks. We expect reliable PPI annotations to show that proteins interacting in vivo are co-located in the same cellular compartment. Our goal here is to evaluate the potential of using PPI annotation in determining SCL of proteins in human, mouse, fly and yeast, and to identify and quantify the factors that contribute to this complementarity

    Beliefs About the Direct Comparison of E-Cigarettes and Cigarettes

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    Background: Recent data suggests that positive beliefs about electronic cigarettes (e-cigs) use can lead to later e-cig use. Considering that many advertisements claim that e-cigs are superior to cigarettes, individuals' likelihood to view e-cigs more favorably than cigarettes can also influence subsequent e-cig use; however, no studies have directly assessed such a comparison. Objectives: The present study created and validated the Comparing E-Cigarettes and Cigarettes questionnaire (CEAC), which asks individuals to directly compare e-cigs and cigarettes on a number of dimensions, in two independent samples. Methods: In sample 1 (451 undergraduates; mean age = 20.35, SD = 5.44, 72.4% female, 73.4% Caucasian) we explored the factor structure of the CEAC and in sample 2 (699 community adults collected via Amazon's Mechanical Turk; mean age = 34.04, SD = 10.9, 47.7% female, 83.3% Caucasian) we replicated the factor structure. Results: Exploratory factor analysis suggested a three-factor structure: General Benefits (α = 0.80), General Effects (α = 0.86), and Health Benefits (α = 0.88), which was replicated via confirmatory factor analysis, χ2 = 4.36; RMSEA = 0.07, 90% CI = 0.06–0.08; TLI = 0.99; CFI = 0.99, and was relatively invariant across product use and gender. Individuals reported viewing e-cigs as safer and more beneficial than cigarettes and these beliefs were higher in e-cig users. Conclusions: Future work should establish how these comparative beliefs are influenced by e-cig use and/or influence subsequent transition to and increases in e-cig use. Although e-cigs are likely less harmful than cigarettes, and thus these comparative beliefs represent that state of nature, e-cigs are not completely without risk

    Transitioning from cigarettes to electronic cigarettes increases alcohol consumption

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    Objective Electronic cigarettes (e-cigs) are a nicotine delivery device that have recently been linked to alcohol use. Many individuals that smoke cigarettes transition to e-cigs as an alternative to cigarette use, despite potential negative health effects of e-cigs. No research to date has examined how former smokers that have transitioned to e-cigs differ from former smokers that do not use e-cigs, particularly in relation to alcohol use. Further, no research has examined how former smokers that use e-cigs regularly or socially may differ in alcohol consumption. Method Using an online community dwelling sample (Former smokers N=198, mean age=34.70, SD=11.45, 56.1% female, 78.3% Caucasian, 37.9% e-cig users), the present study assessed smoking status and alcohol use, with the latter assessed using a Timeline Followback calendar and the Alcohol Use Disorder Identification Test (AUDIT). Results In all former smokers, total drinks (b=4.01, p=0.02) and average drinks per drinking day (b=0.61, p=.01) were both related to e-cig use status, with e-cig users reporting higher alcohol consumption. Among e-cig using former smokers, social users, but not regular users, showed positive relationships with AUDIT scores, b=1.90, p=.02, total drinks, b=9.12, p<.001, average drinks, b=0.98, p=.006, and hazardous drinking status, OR=3.21, p=.01. Conclusions Findings suggest that: (1) former smokers who use e-cigs may have a potential for higher alcohol use; and (2) those who use e-cigs socially may be at heightened risk for hazardous patterns of alcohol consumption. This should be taken into consideration by healthcare providers

    A Comprehensive Audit of Professional Development for K-12 School Leaders in the Commonwealth of Virginia

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    The intent of this paper is to provide a mixed-methods audit of professional development provided to K-12 school leadership in Virginia\u27s diverse landscape to include identification of providers, funding, effectiveness, and expectations. In the Commonwealth of Virginia, geographical, political, and socio-economical differences across 132 school divisions cause variability in leaders\u27 experiences with professional development. A mixed-methods approach was used, including a review of current literature, an online survey, virtual interviews, and virtual focus group discussions. This data collection results in a comprehensive audit of professional development provided to school leaders in Virginia\u27s diverse landscape. The study defines effective professional development for school leaders and considers commonalities and disparities of school leaders\u27 experience with professional development, including divisions\u27 commitment to funding, leaders’ access to providers, and leaders’ exposure to traditional and emerging content topics in order to provide recommendations to Virginia Commonwealth University\u27s School of Education as an external provider of professional development for school leaders
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