233 research outputs found

    Influence of Gamma-Ray Emission on the Isotopic Composition of Clouds in the Interstellar Medium

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    We investigate one mechanism of the change in the isotopic composition of cosmologically distant clouds of interstellar gas whose matter was subjected only slightly to star formation processes. According to the standard cosmological model, the isotopic composition of the gas in such clouds was formed at the epoch of Big Bang nucleosynthesis and is determined only by the baryon density in the Universe. The dispersion in the available cloud composition observations exceeds the errors of individual measurements. This may indicate that there are mechanisms of the change in the composition of matter in the Universe after the completion of Big Bang nucleosynthesis. We have calculated the destruction and production rates of light isotopes (D, 3He, 4He) under the influence of photonuclear reactions triggered by the gamma-ray emission from active galactic nuclei (AGNs). We investigate the destruction and production of light elements depending on the spectral characteristics of the gamma-ray emission. We show that in comparison with previous works, taking into account the influence of spectral hardness on the photonuclear reaction rates can increase the characteristic radii of influence of the gamma-ray emission from AGNs by a factor of 2-8. The high gamma-ray luminosities of AGNs observed in recent years increase the previous estimates of the characteristic radii by two orders of magnitude. This may suggest that the influence of the emission from AGNs on the change in the composition of the medium in the immediate neighborhood (the host galaxy) has been underestimated.Comment: 13 pages, 13 figures, 3 table

    Building consensus: idea brokerage in teacher policy networks

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    This is the author accepted manuscript.We show how policy makers converged to support similar reforms on a major educational issue: teacher effectiveness. Our study demonstrates the importance of idea brokers—actors that facilitate connections between preferences in policy networks and promote consensus around new policy ideas. Our study is based on analysis of testimony from 200 Congressional hearingsfrom 2001 to 2015. We use discourse network analysis to examine network ties based on policy preferences expressed in hearings. We visualize policy networks, identify brokers, and estimate exponential random graph models to examine policy changes between the Bush and Obama administrations. We show how idea brokerage is associated with a convergence of policy preferences around teacher effectiveness among a coalition of political actors.William T. Grant Foundatio

    STEM leaders promoting resilience within equity-centered K-12 STEM education organizations

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    IntroductionThis study examines storytelling’s role in supporting organizational resilience for equitable STEM instruction by schools and districts. Within K-12 organizations, some practices may be perceived as mundane, but storytelling supports transformation toward achieving equitable STEM learning opportunities in a school. Therefore, storytelling is a means for achieving organizational resilience.MethodsThrough a comparative case study design, this paper explores challenges identified by educational leaders through focus groups who worked with teams to activate interdisciplinary learning to support thriving STEM programming to enhance equitable science instruction.ResultsWe characterize STEM systems’ social and organizational phenomena from three educational contexts. We start by sharing these systems’ backgrounds and educational goals, with specific attentiveness to their STEM programming. We then share the stories told by their leaders to promote organizational resilience (these characteristics, as previously described, are italicized throughout this section) within each of the given contexts.DiscussionThe STEM stories in this study shared the state of STEM within a school and district, the instructional mission of STEM, and a community STEM story

    USU Teaching Documentation: Dossiers from the Mentoring Program

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    The nation\u27s land grant institutions were founded on the principle of access for the general public to the knowledge gained through research and creative activity fostered in higher education. Central to our access mission is our dedication to teaching and learning that is informed by research and discovery, both of which must result, at least in part, from our engagement with our external constituents. That teaching and learning informs our research and vice versa; our research informs and aids in our teaching mission. This work, compiled by Professors Maria Luisa Spicer-Escalante and Cathy Ferrand Bullock, is focused on how the best, highly informed teaching is accomplished when done in an intentional manner. That intentional process helps the best university educators thoughtfully build their teaching story in an organized manner. Educators think about how they can successfully reach and engage their appropriate student audiences (or mentees), what they hope to accomplish, and how they intend to accomplish their goals. Further, as learning outcomes are identified and established, first-rate methods for course design, content inclusion, and continuous improvement can be outlined. Those of us who follow these intentional principles may then detail our growth and success along the way as teachers in the development of documents that tell our stories. Undoubtedly, the ability to clearly document and articulate that story will help academic personnel add to their tenure and promotion preparation in a very meaningful way. But as or even more important is the opportunity to describe these journeys with all the efforts, large and small, of improving their product in terms of learning outcomes and student growth and success. The nuggets of wisdom compiled by Professors Spicer-Escalante and Bullock, in USU Teaching Documentation: Dossiers from the Mentoring Program, will help teachers across the board from the new lecturer or assistant professor to the experienced professor dive into their teaching programs and find ways to continuously experiment and refine their approaches to our critically important student audiences. Good luck, teach on, and successfully document some of the most important work you all do! Frank Galey Executive Vice President and Provost Utah State University 2019https://digitalcommons.usu.edu/ua_faculty/1000/thumbnail.jp

    The role of Prototyping in Ergonomic Practice and Research to Anticipate New Products and Services

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    This article argues for the dual role of prototyping in facilitating abductive thinking in research and practice within “Ergonomics” and “Design”. Moreover, this duality also pertains to the development of innovative commodities, as well as in the acquisition of new knowledge. Since PE investigates real-life scenarios the aim of the researcher is to understand the nature and complexity of the future state of the system. In this sense prototypes can be used as probes into that future state due to the fact that once implemented they unveil real interactions and transformations of the system. Based on the act of design as a critical inquiry in itself, prototypes and prototyping are then being more and more perceived as carriers of reflection and argumentation From a pedagogical perspective, prototyping exposes students to larger issues around creating and testing operational models of knowledge. Reversely, when being engaged in collaborative project with industry, prototyping can play an expanded as well as a more effective role in conceptualizing innovative solutions in an efficient manner.acceptedVersionPublisher embargo applies until August 13, 201

    The Vehicle, 1964, Vol. 6

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    Vol. 6 Table of Contents Milepostspage 2 John Fitzgerald Kennedy Memorial Pagepage 4 Sadness No. 4 (Sorgen)Sherry S. Frypage 5 Christian BurialRoger J. Barrypage 7 The World of BeautyDavid Helmpage 9 The Song of the LarksDon Kapraunpage 10 ContrastKeith Haierpage 13 PanoramaDaun Alan Leggpage 13 A Child\u27s View of DeathCherie Brondellpage 14 RegretLiz Puckettpage 16 Brutal WarMary H. Soukuppage 17 aloneLiz Puckettpage 18 MadgeLinda Galeypage 19 Moon WatchingJoel E. Hendrickspage 20 AnalysisLiz Puckettpage 21 UniverseRick Talleypage 21 Anyone Can Be A LuniticRick Towsonpage 22 I, Too, Have A Rendezvous with DeathElaine Lancepage 23 The ReturnRobert D. Thomaspage 24 NamesLarry Gatespage 25 Eternal MomentsDavid Helmpage 25 The Last DaysPauline B. Smithpage 26 BeliefRichard J. Wiesepage 27 StormPauline B. Smithpage 28 ExplosionLiz Puckettpage 29 Autumn EveJoel E. Hendrickspage 29 The Girl On the White PonyLarry Gatespage 31 HoffnungTerry Michael Salempage 33 Stone WallsDaun Alan Leggpage 34 AdorationGail M. Barenfangerpage 37 MirageRoy L. Carlsonpage 38 Nature and NonsenseRick Talleypage 39 A Step Through A Looking GlassMarilyn Henrypage 40 Thoughts of a Summer PastPauline B Smithpage 42 Indiana GrassLarry Gatespage 43 RedondillaRoberta Matthewspage 44 Summer LoveDaun Alan Leggpage 45 To Youth Reaching For MaturityDavid Helmpage 45 Thanksgiving DayJoel E. Hendrickspage 46 Sadness No. 6 (Schatten)Sherry S. Frypage 48https://thekeep.eiu.edu/vehicle/1012/thumbnail.jp

    Hepatopathy following consumption of a commercially available blue-green algae dietary supplement in a dog

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    BACKGROUND: Dietary supplement use in both human and animals to augment overall health continues to increase and represents a potential health risk due to the lack of safety regulations imposed on the manufacturers. Because there are no requirements for demonstrating safety and efficacy prior to marketing, dietary supplements may contain potentially toxic contaminants such as hepatotoxic microcystins produced by several species of blue-green algae. CASE PRESENTATION: An 11-year-old female spayed 8.95 kg Pug dog was initially presented for poor appetite, lethargy polyuria, polydipsia, and an inability to get comfortable. Markedly increased liver enzyme activities were detected with no corresponding abnormalities evident on abdominal ultrasound. A few days later the liver enzyme activities were persistently increased and the dog was coagulopathic indicating substantial liver dysfunction. The dog was hospitalized for further care consisting of oral S-adenosylmethionine, silybin, vitamin K, and ursodeoxycholic acid, as well as intravenous ampicillin sodium/sulbactam sodium, dolasetron, N-acetylcysteine, metoclopramide, and intravenous fluids. Improvement of the hepatopathy and the dog’s clinical status was noted over the next three days. Assessment of the dog’s diet revealed the use of a commercially available blue-green algae dietary supplement for three-and-a-half weeks prior to hospitalization. The supplement was submitted for toxicology testing and revealed the presence of hepatotoxic microcystins (MCs), MC-LR and MC-LA. Use of the supplement was discontinued and follow-up evaluation over the next few weeks revealed a complete resolution of the hepatopathy. CONCLUSIONS: To the authors’ knowledge, this is the first case report of microcystin intoxication in a dog after using a commercially available blue-green algae dietary supplement. Veterinarians should recognize the potential harm that these supplements may cause and know that with intervention, recovery is possible. In addition, more prudent oversight of dietary supplement use is recommended for our companion animals to prevent adverse events/intoxications

    The Natural Products Atlas: An Open Access Knowledge Base for Microbial Natural Products Discovery

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    \ua9 2019 American Chemical Society. Despite rapid evolution in the area of microbial natural products chemistry, there is currently no open access database containing all microbially produced natural product structures. Lack of availability of these data is preventing the implementation of new technologies in natural products science. Specifically, development of new computational strategies for compound characterization and identification are being hampered by the lack of a comprehensive database of known compounds against which to compare experimental data. The creation of an open access, community-maintained database of microbial natural product structures would enable the development of new technologies in natural products discovery and improve the interoperability of existing natural products data resources. However, these data are spread unevenly throughout the historical scientific literature, including both journal articles and international patents. These documents have no standard format, are often not digitized as machine readable text, and are not publicly available. Further, none of these documents have associated structure files (e.g., MOL, InChI, or SMILES), instead containing images of structures. This makes extraction and formatting of relevant natural products data a formidable challenge. Using a combination of manual curation and automated data mining approaches we have created a database of microbial natural products (The Natural Products Atlas, www.npatlas.org) that includes 24 594 compounds and contains referenced data for structure, compound names, source organisms, isolation references, total syntheses, and instances of structural reassignment. This database is accompanied by an interactive web portal that permits searching by structure, substructure, and physical properties. The Web site also provides mechanisms for visualizing natural products chemical space and dashboards for displaying author and discovery timeline data. These interactive tools offer a powerful knowledge base for natural products discovery with a central interface for structure and property-based searching and presents new viewpoints on structural diversity in natural products. The Natural Products Atlas has been developed under FAIR principles (Findable, Accessible, Interoperable, and Reusable) and is integrated with other emerging natural product databases, including the Minimum Information About a Biosynthetic Gene Cluster (MIBiG) repository, and the Global Natural Products Social Molecular Networking (GNPS) platform. It is designed as a community-supported resource to provide a central repository for known natural product structures from microorganisms and is the first comprehensive, open access resource of this type. It is expected that the Natural Products Atlas will enable the development of new natural products discovery modalities and accelerate the process of structural characterization for complex natural products libraries

    \u3ci\u3eSenecio Conrathii\u3c/i\u3e N.E.Br. (Asteraceae), a New Hyperaccumulator of Nickel from Serpentinite Outcrops of the Barberton Greenstone Belt, South Africa

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    Five nickel hyperaccumulators belonging to the Asteraceae are known from ultramafic outcrops in South Africa. Phytoremediation applications of the known hyperaccumulators in the Asteraceae, such as the indigenous Berkheya coddii Roessler, are well reported and necessitate further exploration to find additional species with such traits. This study targeted the most frequently occurring species of the Asteraceae on eight randomly selected serpentinite outcrops of the Barberton Greenstone Belt. Twenty species were sampled, including 12 that were tested for nickel accumulation for the first time. Although the majority of the species were excluders, the known hyperaccumulators Berkheya nivea N.E.Br. and B. zeyheri (Sond. & Harv.) Oliv. & Hiern subsp. rehmannii (Thell.) Roessler var. rogersiana (Thell.) Roessler hyperaccumulated nickel in the leaves at expected levels. A new hyperaccumulator of nickel was discovered, Senecio conrathii N.E.Br., which accumulated the element in its leaves at 1695 ± 637 µg g−1 on soil with a total and exchangeable nickel content of 503 mg kg−1 and 0.095 µg g−1, respectively. This makes it the third known species in the Senecioneae of South Africa to hyperaccumulate nickel after Senecio anomalochrous Hilliard and Senecio coronatus (Thunb.) Harv., albeit it being a weak accumulator compared with the latter. Seven tribes in the Asteraceae have now been screened for hyperaccumulation in South Africa, with hyperaccumulators only recorded for the Arctoteae and Senecioneae. This suggests that further exploration for hyperaccumulators should focus on these tribes as they comprise all six species (of 68 Asteraceae taxa screened thus far) to hyperaccumulate nickel
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