2,325 research outputs found

    The distribution and diversity of an entire assemblage of Plecoptera (stoneflies) inhabiting Indiana, USA

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    Plecoptera are an environmentally sensitive order of aquatic insects commonly used in water quality monitoring and are experiencing declines across the globe. A dataset containing over 6,300 specimen records from regional museums, literature records, and new collections was used to answer three major questions. How many species are found in the state of Indiana? How are those species distributed across the HUC8 drainages of the state? What landscape factors have the greatest impact on species richness within HUC8 watersheds? The dataset revealed a total of 93 species recorded from the state. The three richest of 38 HUC8s were the Lower East Fork White (66 species), the Blue-Sinking (58), and the Lower White (51) drainages, all concentrated in the southern unglaciated part of the state. Results from K-means cluster analysis suggests that species assemblages of HUC8 drainages form two clusters: one northern cluster primarily composed of drainages north of the limit of Wisconsinan glaciation, and a southern cluster primarily composed of those drainages which were unglaciated or were glaciated only during the Illinoian period. HUC8 drainage richness was predicted using nine variables, reduced from 116 and subjected to AICc Importance and Hierarchical Partitioning. AICc Importance revealed four variables associated with Plecoptera species richness, topographic wetness index, HUC8 area, percent soil hydrologic group C/D, and percent historic wetland ecosystem. Hierarchical Partitioning indicated topographic wetness index, HUC8 area, and percent cherty red clay surface geology as significantly important to predicting species richness

    PLECOPTERA OR STONEFLIES (INSECTA) OF INDIANA: DIVERSITY AND CONSERVATION STATUS OF SPECIES

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    Stoneflies (Plecoptera) are indicators of water quality and have been lost in dramatic numbers from Midwest states, including Indiana. This study synthesizes over 5,000 specimen level records from museums and recent fieldwork to build a current species list, assess watershed level species richness, and calculate state level conservation assessments using NatureServe’s Conservation Rank Calculator. Results include 1,050 positive occurrence records that yielded 92 species. Among these is one recently described species, a new species not yet described, and three previously described species new to Indiana. We have also found additional locations for rare species and confirmed the presence of a few species thought to be extirpated. United States Geological Survey Hierarchical Unit Code scale 6 (HUC6) drainages with the highest species richness values were the Patoka-White (73 species), Lower Ohio-Salt (60 species), and the Wabash River (57 species). The other seven drainages produced from five to 28 species, being limited by low gradient streams due to lake plain landscapes and by stream nutrient enrichment from agriculture. Eleven species were rated as extirpated or presumed extirpated, leaving 81 extant species. Of these, 17 were rated as critically imperiled (S1), 26 imperiled (S2), 25 vulnerable (S3), while only 13 species were rated as secure (S4 & S5). Watersheds and specific streams were discussed for their ability to support individual species or rich assemblages.Indianapolis Zoo funded via Indiana Department of Natural Resourcesunpublishednot peer reviewedOpe

    The DEEP2 Redshift Survey: Lyman Alpha Emitters in the Spectroscopic Database

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    We present the first results of a search for Lyman-alpha emitters (LAEs) in the DEEP2 spectroscopic database that uses a search technique that is different from but complementary to traditional narrowband imaging surveys. We have visually inspected ~20% of the available DEEP2 spectroscopic data and have found nine high-quality LAEs with clearly asymmetric line profiles and an additional ten objects of lower quality, some of which may also be LAEs. Our survey is most sensitive to LAEs at z=4.4-4.9 and that is indeed where all but one of our high-quality objects are found. We find the number density of our spectroscopically-discovered LAEs to be consistent with those found in narrowband imaging searches. The combined, averaged spectrum of our nine high-quality objects is well fit by a two-component model, with a second, lower-amplitude component redshifted by ~420 km/s with respect to the primary Lyman-alpha line, consistent with large-scale outflows from these objects. We conclude by discussing the advantages and future prospects of blank-sky spectroscopic surveys for high-z LAEs.Comment: Accepted for publication in Ap

    Population Stratification of a Common APOBEC Gene Deletion Polymorphism

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    The APOBEC3 gene family plays a role in innate cellular immunity inhibiting retroviral infection, hepatitis B virus propagation, and the retrotransposition of endogenous elements. We present a detailed sequence and population genetic analysis of a 29.5-kb common human deletion polymorphism that removes the APOBEC3B gene. We developed a PCR-based genotyping assay, characterized 1,277 human diversity samples, and found that the frequency of the deletion allele varies significantly among major continental groups (global F (ST) = 0.2843). The deletion is rare in Africans and Europeans (frequency of 0.9% and 6%), more common in East Asians and Amerindians (36.9% and 57.7%), and almost fixed in Oceanic populations (92.9%). Despite a worldwide frequency of 22.5%, analysis of data from the International HapMap Project reveals that no single existing tag single nucleotide polymorphism may serve as a surrogate for the deletion variant, emphasizing that without careful analysis its phenotypic impact may be overlooked in association studies. Application of haplotype-based tests for selection revealed potential pitfalls in the direct application of existing methods to the analysis of genomic structural variation. These data emphasize the importance of directly genotyping structural variation in association studies and of accurately resolving variant breakpoints before proceeding with more detailed population-genetic analysis

    Explaining Reinforcement Learning to Mere Mortals: An Empirical Study

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    We present a user study to investigate the impact of explanations on non-experts' understanding of reinforcement learning (RL) agents. We investigate both a common RL visualization, saliency maps (the focus of attention), and a more recent explanation type, reward-decomposition bars (predictions of future types of rewards). We designed a 124 participant, four-treatment experiment to compare participants' mental models of an RL agent in a simple Real-Time Strategy (RTS) game. Our results show that the combination of both saliency and reward bars were needed to achieve a statistically significant improvement in mental model score over the control. In addition, our qualitative analysis of the data reveals a number of effects for further study.Comment: 7 page

    Refining Research Representations through Fiction, Journalism, and Creative Non-Fiction Writing Ideas

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    Research accounts have been critiqued as boring and unreasonably difficult to read when the actual research process is deeply fascinating and should be accessible to many. Academic researchers should draw on the creative writing disciplines (e.g., fiction, creative nonfiction, journalism) in order to improve the quality of written research accounts, and there are numerous style guides that give guidance on how to improve the quality of writing. An understanding of different academic disciplines’ style expectations seems to be needed in order to Publish and Persevere, yet literary understandings of writing will allow us to enliven writing in engaging ways. It is important to acknowledge that requiring strict adherence to style guides may be a form of intersectional oppression of race, class, and region that is seldom reflected upon. In this article, the authors review four style guides from the areas of journalism and creative writing, including the classics guides The Elements of Style (Strunk & White, 1959) and On Writing Well (Zinsser, 2006), as well as Thrice Told Tales: Three Mice Full of Writing Advice (Lewis, 2013), a contemporary guide with eye catching graphics, and The Writing Life (1989), literary author Annie Dillard’s reflective thoughts on writing

    Stellar Mass--Gas-phase Metallicity Relation at 0.5z0.70.5\leq z\leq0.7: A Power Law with Increasing Scatter toward the Low-mass Regime

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    We present the stellar mass (MM_{*})--gas-phase metallicity relation (MZR) and its scatter at intermediate redshifts (0.5z0.70.5\leq z\leq0.7) for 1381 field galaxies collected from deep spectroscopic surveys. The star formation rate (SFR) and color at a given MM_{*} of this magnitude-limited (R24R\lesssim24 AB) sample are representative of normal star-forming galaxies. For masses below 109M10^9 M_\odot, our sample of 237 galaxies is \sim10 times larger than those in previous studies beyond the local universe. This huge gain in sample size enables superior constraints on the MZR and its scatter in the low-mass regime. We find a power-law MZR at 108M<M<1011M10^{8} M_\odot < M_{*} < 10^{11} M_\odot: 12+log(O/H)=(5.83±0.19)+(0.30±0.02)log(M/M){12+log(O/H) = (5.83\pm0.19) + (0.30\pm0.02)log(M_{*}/M_\odot)}. Our MZR shows good agreement with others measured at similar redshifts in the literature in the intermediate and massive regimes, but is shallower than the extrapolation of the MZRs of others to masses below 109M10^{9} M_\odot. The SFR dependence of the MZR in our sample is weaker than that found for local galaxies (known as the Fundamental Metallicity Relation). Compared to a variety of theoretical models, the slope of our MZR for low-mass galaxies agrees well with predictions incorporating supernova energy-driven winds. Being robust against currently uncertain metallicity calibrations, the scatter of the MZR serves as a powerful diagnostic of the stochastic history of gas accretion, gas recycling, and star formation of low-mass galaxies. Our major result is that the scatter of our MZR increases as MM_{*} decreases. Our result implies that either the scatter of the baryonic accretion rate or the scatter of the MM_{*}--MhaloM_{halo} relation increases as MM_{*} decreases. Moreover, our measures of scatter at z=0.7z=0.7 appears consistent with that found for local galaxies.Comment: 18 pages, 10 figures. Accepted by ApJ. Typos correcte

    The DEEP2 Redshift Survey: Lyα Emitters in the Spectroscopic Database

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    We present the first results of a search for Lyα emitters (LAEs) in the DEEP2 spectroscopic database that uses a search technique that is different from but complementary to traditional narrowband imaging surveys. We have visually inspected ~20% of the available DEEP2 spectroscopic data and have found nine high-quality LAEs with clearly asymmetric line profiles and an additional 10 objects of lower quality, some of which may also be LAEs. Our survey is most sensitive to LAEs at z = 4.4–4.9 and that is indeed where all but one of our high-quality objects are found. We find the number density of our spectroscopically discovered LAEs to be consistent with those found in narrowband imaging searches. The combined, averaged spectrum of our nine high-quality objects is well fit by a two-component model, with a second, lower amplitude component redshifted by ~420 km s^(−1) with respect to the primary Lyα line, consistent with large-scale outflows from these objects. We conclude by discussing the advantages and future prospects of blank-sky spectroscopic surveys for high-z LAEs

    Removal of Kidney Stones by Extracorporeal Shock Wave Lithotripsy Is Associated with Delayed Progression of Chronic Kidney Disease

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    ∙ The authors have no financial conflicts of interest. © Copyright: Yonsei University College of Medicine 2012 This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial Licens
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