7,426 research outputs found

    Determining the Accessibility of Zeolite L Channels Using the Color Change of Thionine Dyes

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    Host-guest materials are created when a guest dye molecule enters the channels within the zeolite host, which can be useful to understand how molecules act in a constrained environment. In the study of Zeolite L, it was previously unclear if Brooker’s merocyanine was able to go into the channels of Zeolite L. The purpose of this research was to determine if thionine dye could be inserted into the zeolite crystal channels and how much dye would be adsorbed. Thionine was chosen as a guest dye to compare synthesized zeolite with known literature behavior. Zeolite L was synthesized in the lab, and the crystal structure was confirmed with XRD. Then, a zeolite suspension was added to a 2.5 x 10-5 M aqueous thionine solution and heated to boiling until the solution turned from purple to blue. The color change indicated that the dye molecules entered the channels of the zeolite, which lead to three conclusions. First, the synthesized Zeolite L channels could incorporate dye molecules, which followed the literature example. This project also proved to be a faster way of confirming that the crystal was correct versus examining the crystal in the XRD. Lastly, the amount of dye that entered the zeolite channels was measured and compared to previous studies

    Applications of ISES for geology

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    The principal applications for onboard data processing and real-time data transmission in the geological sciences are the detection of early warning signs of potential catastrophic events and the rapid assessment of impact and damage following major events. Also, the opportunity for quick look and supporting data during field investigations should not be disregarded. The Eos platforms are ideal for these applications because of the variety of earth sensing instruments and their differing modes of operation. Further study is required to define the role for each instrument and to assess how they can aid each other in establishing an improved output product

    Guide to the National Invertebrate Database (NID)

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    Molecular docking and geographical information systems as tools to assess the potential impact of veterinary medicines on non-target organisms and the environment

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    Veterinary medicines (VMs) from agricultural industry can enter the environment in a number of ways. This includes direct exposure through aquaculture, accidental spillage and disposal, and indirect entry by leaching from manure or runoff after treatment. Many compounds used in animal treatments have ecotoxic properties that may have chronic or sometimes lethal effects when they come into contact with non-target organisms. VMs enter the environment in mixtures, potentially having additive effects. Traditional ecotoxicology tests are used to determine the lethal and sometimes reproductive effects on freshwater and terrestrial organisms. However, organisms used in ecotoxicology tests can be unrepresentative of the populations that are likely to be exposed to the compound in the environment. Most often the tests are on single compound toxicity but mixture effects may be significant and should be included in ecotoxicology testing. This work investigates the use, measured environmental concentrations (MECs) and potential impact of sea lice treatments on salmon farms in Scotland. Alternative methods for ecotoxicology testing including mixture toxicity, and the use of in silico techniques to predict the chronic impact of VMs on different species of aquatic organisms were also investigated. The Scottish Environmental Protection Agency (SEPA) provided information on the use of five sea lice treatments from 2008-2011 on Scottish salmon farms. This information was combined with the recently available data on sediment MECs for the years 2009-2012 provided by SEPA using ArcGIS 10.1. In depth analysis of this data showed that from a total of 55 sites, 30 sites had a MEC higher than the maximum allowable concentration (MAC) as set out by SEPA for emamectin benzoate and 7 sites had a higher MEC than MAC for teflubenzuron. A number of sites that were up to 16 km away from the nearest salmon farm reported as using either emamectin benzoate or teflubenzuron measured positive for the two treatments. There was no relationship between current direction and the distribution of the sea lice treatments, nor was there any evidence for alternative sources of the compounds e.g. land treatments. The sites that had MECs higher than the MAC could pose a risk to non-target organisms and disrupt the species dynamics of the area. There was evidence that some marine protected sites might be at risk of exposure to these compounds. To complement this work, effects on acute mixture toxicity of the 5 sea lice treatments, plus one major metabolite 3-phenoxybenzoic acid (3PBA), were measured using an assay using the bioluminescent bacteria Aliivibrio fischeri. When exposed to the 5 sea lice treatments and 3PBA A. fischeri showed a response to 3PBA, emamectin benzoate and azamethiphos as well as combinations of the three. In order to establish any additive effect of the sea lice treatments, the efficacy of two mixture prediction equations, concentration addition (CA) and independent action ii(IA) were tested using the results from single compound dose response curves. In this instance IA was the more effective prediction method with a linear regression confidence interval of 82.6% compared with 22.6% of CA. In silico molecular docking was carried out to predict the chronic effects of 15 VMs (including the five used as sea lice control). Molecular docking has been proposed as an alternative screening method for the chronic effects of large animal treatments on non-target organisms. Oestrogen receptor alpha (ERα) of 7 non-target bony fish and the African clawed frog Xenopus laevis were modelled using SwissModel. These models were then ‘docked’ to oestradiol, the synthetic oestrogen ethinylestradiol, two known xenoestrogens dichlorodiphenyltrichloroethane (DDT) and bisphenol A (BPA), the antioestrogen breast cancer treatment tamoxifen and 15 VMs using Auto Dock 4. Based on the results of this work, four VMs were identified as being possible xenoestrogens or anti-oestrogens; these were cypermethrin, deltamethrin, fenbendazole and teflubenzuron. Further investigation, using in vitro assays, into these four VMs has been suggested as future work. A modified recombinant yeast oestrogen screen (YES) was attempted using the cDNA of the ERα of the zebrafish Danio rerio and the rainbow trout Oncorhynchus mykiss. Due to time and difficulties in cloning protocols this work was unable to be completed. Use of such in vitro assays would allow for further investigation of the highlighted VMs into their oestrogenic potential. In conclusion, VMs used as sea lice treatments, such as teflubenzuron and emamectin benzoate may be more persistent and have a wider range in the environment than previously thought. Mixtures of sea lice treatments have been found to persist together in the environment, and effects of these mixtures on the bacteria A. fischeri can be predicted using the IA equation. Finally, molecular docking may be a suitable tool to predict chronic endocrine disrupting effects and identify varying degrees of impact on the ERα of nine species of aquatic organisms

    Introduction to Library Trends 47 (2) Fall 1998: How Classifications Work: Problems and Challenges in an Electronic Age

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    published or submitted for publicatio

    ESTIMATION OF THE NONMARKET BENEFITS OF AGRICULTURAL LAND RETENTION IN EASTERN CANADA

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    We assess the nonmarket value for retention of farmland in the Moncton area of New Brunswick. We examine a number of factors explaining household external values for farmland preservation and expand on previous work by Beasley et al., Bergstrom et al., and Halstead. Our findings indicate that the marginal external benefit of preserving farmland in general in this region is small compared to the market price and that spatial embedding is not automatic in contingent valuation studies.Land Economics/Use,

    THE ENDOWMENT EFFECT AND WTA: A QUASI-EXPERIMENTAL TEST

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    This paper reports a test of the endowment effect in an economic analysis of localized air pollution. Regression techniques are used to test the significance of perceived property rights on household WTP for improved air quality versus WTA compensation to forgo an improvement in air quality. Our experiment contributes to the research into the WTP/WTA divergence by providing a new basis for supporting the existence of an endowment effect. Our results are in contrast to recent work by Shogren et al. which supports the substitution proposition of Hanemann while rejecting the endowment effect.Contingent valuation, Endowment effect, Property rights, Substitution effect, Environmental Economics and Policy,

    ‘Our voice started off as a whisper and now it is a great big roar’ : The Salford Dementia Associate Panel as a model of involvement in research activities

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    This paper presents the work of the ‘Salford Dementia Associate Panel’, based at the Salford Institute for Dementia, Salford University (UK). We discuss the roles of the Dementia Associates, in particular around the areas of engagement and research. The panel is made up of people living with dementia, and current and former care partners. It highlights the development of this group over a four-year period and demonstrates over time how the role of a Dementia Associate member has evolved. The panel is involved in research, education and public engagement activities conducted by staff and students within the Institute. The motivations for becoming involved are clearly articulated and demonstrate how the personal backgrounds of individuals have driven the collective involvement and desire to bring about change. The benefits and challenges associated with working as part of a panel are discussed. We conclude by bringing together our experiences as a set of suggestions for others who may wish to create a similar forum to promote the involvement of people living with dementia and former and current care partners
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