1,023 research outputs found

    Definitions of Water Quality: A Survey of Lake-Users of Water Quality-Compromised Lakes

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    Understanding and defining water quality is an important precursor for influencing pro-environmental behavior and accurately assessing potential outcomes of human–lake interactions. This study surveyed 82 lake-users in Nebraska regarding their definitions of water quality and the importance of various water quality features to determine if lake-users’ definitions align with complex and multi-faceted governmental and scientific definitions. Survey sites included two recreational reservoirs (e.g., boating and fishing), Holmes Lake (urban watershed) and Branched Oak Lake (agricultural watershed). The biological and chemical parameters are similar between the lakes and both lakes were listed as “impaired” on the Section 303(d) (United States Environmental Protection Agency,Washington, DC, USA) list of impaired waters of the US at the time of the surveys. The results of our survey suggest that the overwhelming majority of lake-users’ self-generated definitions of water quality did not include more than one feature of water quality found in the relevant policy and regulatory definitions and they focused primarily on water clarity. Further, when provided a list of specific water quality features, the participants rated all provided features of water quality as highly important. This suggests that the failure to include those features in a self-generated definition is not the consequence of perceiving that feature as low importance

    Energy Conversion Alternatives Study (ECAS), General Electric Phase 1. Volume 3: Energy Conversion subsystems and components. Part 2: Primary heat input systems and heat exchangers

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    Primary heat input systems and heat exchangers were evaluated for advanced energy conversion systems. Results are presented and discussed

    CAUGHT BETWEEN A ROCK AND A HARD MINERAL ENCRUSTATION: LONG-LIVED AQUATIC INSECTS ACCUMULATE CALCIUM CARBONATE DEPOSITS IN A MONTANE DESERT STREAM

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    Aquatic ecosystems overlying regions of limestone bedrock can feature active deposition of calcium carbonate in the form of travertine or tufa. Although most travertine deposits form a cement-like layer on stream substrates, mineral deposits can also form on benthic invertebrates. However, little is known about which taxa may be prone to calcium carbonate encrustation and which life history traits may make taxa more susceptible to becoming encrusted. Here we report the presence of calcium carbonate deposits on live insects collected from a montane stream in the Madrean Sky Islands (Huachuca Mountains) of Arizona between 2011 and 2013. Life history differences are examined between taxa with and without travertine deposits. Thirteen genera of aquatic insects were found with calcium carbonate deposits on the exoskeleton as well as 22 other genera, also encountered in the study stream, that have not previously been found with such deposits. Taxa with calcium carbonate encrustation had significantly longer-lived aquatic stages than those without encrustation. Furthermore, encrustation presence did not differ among aerial dispersal modes. These results suggest that the extent of calcium carbonate deposition on aquatic insects is primarily related to the length of time they are in the stream. Since mineral encrustation may reduce predation pressure and mobility, changes in patterns of travertine formation in these systems may have profound effects on ecological interactions. Los ecosistemas dulceacuícolas ubicados en regiones de roca caliza pueden contener depósitos de carbonato de calcio en forma de travertino o tufa. Aunque muchos depósitos de travertino se encuentran como una capa o manto de cemento sobre el fondo del arroyo, los depósitos también pueden formarse sobre los invertebrados bentónicos. Sin embargo, poco se sabe acerca de las especies que son propensas a los depósitos de travertino, o acerca de las características de estas especies que influyen en tal proceso. En este manuscrito reportamos la presencia de depósitos de travertino en insectos vivos y recolectados en un arroyo montañoso en el Archipiélago Madrense de Arizona durante 2011–2013 y examinamos las diferencias en las historias de vida entre taxones con o sin depósitos de travertino. Encontramos trece géneros de insectos acuáticos con travertino sobre el exoesqueleto y vientedos géneros sin travertino. Los taxones con travertino tienen una fase acuática significativamente más larga que los taxones sin travertino. Además, la presencia de travertino no difirió entre especies con distintas maneras de dispersión aérea. Estos resultados sugieren que las diferencias en los depósitos de travertino en insectos acuáticos ocurren principalmente a causa de la duración del período de vida acuática del insecto. Aunque los depósitos de travertino pueden reducir la presión por depredación y movilidad, cambios en los patrones de formación de travertino en estos sistemas pueden afectar profundamente las interacciones ecológicas

    L-Lysine Imprinted Nanoparticles for Antibody Biorecognition

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    The aim of this study was to prepare L-lysine-imprinted poly(HEMA-MAAsp) nanoparticles which can be used for the adsorption of IgG from aqueous solutions. L-lysine was complexed with MAAsp and Llysine- imprinted poly(HEMA-MAAsp) nanoparticles were synthesized by miniemulsion polymerization. Also, non-imprinted nanoparticles were synthesized without L-lysine for control purpose. L-lysine-imprinted poly(HEMA-MAAsp) nanoparticles were characterized by means of elemental analysis, Fourier transform infrared spectroscopy (FTIR) and transmission electron microscopy (TEM). When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/3500

    The energy partitioning of non-thermal particles in a plasma: or the Coulomb logarithm revisited

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    The charged particle stopping power in a highly ionized and weakly to moderately coupled plasma has been calculated to leading and next-to-leading order by Brown, Preston, and Singleton (BPS). After reviewing the main ideas behind this calculation, we use a Fokker-Planck equation derived by BPS to compute the electron-ion energy partitioning of a charged particle traversing a plasma. The motivation for this application is ignition for inertial confinement fusion -- more energy delivered to the ions means a better chance of ignition, and conversely. It is therefore important to calculate the fractional energy loss to electrons and ions as accurately as possible, as this could have implications for the Laser Megajoule (LMJ) facility in France and the National Ignition Facility (NIF) in the United States. The traditional method by which one calculates the electron-ion energy splitting of a charged particle traversing a plasma involves integrating the stopping power dE/dx. However, as the charged particle slows down and becomes thermalized into the background plasma, this method of calculating the electron-ion energy splitting breaks down. As a result, the method suffers a systematic error of order T/E0, where T is the plasma temperature and E0 is the initial energy of the charged particle. In the case of DT fusion, for example, this can lead to uncertainties as high as 10% or so. The formalism presented here is designed to account for the thermalization process, and in contrast, it provides results that are near-exact.Comment: 10 pages, 3 figures, invited talk at the 35th European Physical Society meeting on plasma physic

    Assessing Two-Mode Semantic Network Story Representations Using a False Memory Paradigm

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    This paper describes a novel method of representing semantic networks of stories (and other text) as a two-mode graph. This method has some advantages over traditional one-mode semantic networks, but has the potential drawback (shared with n-gram text networks) that it contains paths that are not present in the text. An empirical study was devised using a false memory paradigm to determine whether these induced paths are remembered as being true of a set of stories. Results indicate that participants report false memories consistent with the induced paths. Implications for further research and two-mode semantic representations are discussed

    Arteriography during ex vivo renal perfusion A complication

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    A case of bilateral renal-cell carcinoma unsuccessfully treated with bench surgery is reported. The reason for failure was apparently the toxicity of the contrast media used during the ex vivo arteriographic studies. © 1973
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