19,376 research outputs found

    Aphidophagous Coccinellids in Alfalfa, Small Grains, and Maize in Eastern South Dakota

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    In a 13-year study of aphidophagous coccinellids associated with alfalfa (Medicago sativa), maize (Zea mays), and small grain crops in eastern South Dakota, the following species were consistently associated with the crops: Hippodamia convergens, H. tredecimpunctata tibialis, H. parenthesis, Coleomegilla maculata lengi, Coccinella transversoguttata richardsoni, Cycloneda munda, and Adalia bipunctata. All species except A. bipunctata were associated with each of the three crops, while A. bipunctata occurred only in maize. Relative abundances of each species varied among crops and among years. Although only seven species were associated with the crops, additional species were captured on sticky traps stationed adjacent to sampled fields. The species diversity of immature coccinellids did not differ among crops but did differ among years. The diversity of adults differed among crops and years. The site from which samples were taken had no influence on the diversity of immatures or adults. Species relative abundances in alfalfa and small grains were more similar to each other than they were to relative abundances in maize

    An interactive graphics program to retrieve, display, compare, manipulate, curve fit, difference and cross plot wind tunnel data

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    The Aerodynamic Data Analysis and Integration System (ADAIS), developed as a highly interactive computer graphics program capable of manipulating large quantities of data such that addressable elements of a data base can be called up for graphic display, compared, curve fit, stored, retrieved, differenced, etc., was described. The general nature of the system is evidenced by the fact that limited usage has already occurred with data bases consisting of thermodynamic, basic loads, and flight dynamics data. Productivity using ADAIS of five times that for conventional manual methods of wind tunnel data analysis is routinely achieved. In wind tunnel data analysis, data from one or more runs of a particular test may be called up and displayed along with data from one or more runs of a different test. Curves may be faired through the data points by any of four methods, including cubic spline and least squares polynomial fit up to seventh order

    Rotor performance characteristics from an aeroacoustic helicopter wind-tunnel test program

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    An investigation of helicopter rotor noise at model scale was conducted in the Langley 4 by 7 meter tunnel. The program described was the first of a planned three-phase project whose purpose was to examine the characteristic noise mechanism involved in main rotor/tail rotor interaction noise. This first phase was conducted with a main rotor only, in order to identify the characteristic noise generated by only the main rotor. The aerodynamic operating conditions of the rotor system were defined during the test. The acoustic data were properly referenced

    Parasitism, Adult Emergence, Sex Ratio, and Size of \u3ci\u3eAphidius Colemani\u3c/i\u3e (Hymenoptera: Aphidiidae) on Several Aphid Species

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    Aphidius colemani Viereck parasitizes several economically important aphid pests of small grain crops including the greenbug, Schizaphis graminum and the Russian wheat aphid, Diuraphis noxia. The ability of A. colemani to switch from S. graminum to several species of aphids common to agricultural and associated non-agricultural ecosystems in the Great Plains, and the effects of host-change on several biological parameters that influence population growth rate were determined. Female A. colemani parasitized and developed to adulthood in nine of 14 aphid species to which they were exposed in the laboratory. All small grain feeding aphids except Sipha flava were parasi­tized. Two sunflower feeding species (Aphis nerii and A. helianthi) and two crucifer feeding species (Lipaphis erysimi and Brevicoryne brassicae) were parasitized, as was the cotton aphid. Aphis gossypii. The average percentage of aphids parasitized differed significantly among host aphid species. as did the percentage of parasitoids surviving from the mummy to the adult stage and the time required for immature development. The sex ratio of adults that enclosed from the various hosts did not differ significantly among species. Dry weights of adult parasitoids differed significantly among host species. Adults from S. graminum weighed most (0.054 mg) while those emerging from A. helianthi weighed least (0.020 mg). Results are discussed in terms of strategies for classical biological control of aphid pests of cereals

    Lift cruise fan V/STOL aircraft conceptual design study T-39 modification. Volume 1: Technical report

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    The conversion of two T-39 aircraft into lift cruise fan research and technology vehicles is discussed. The concept is based upon modifying the T-39A (NA265-40) Sabreliner airframe into a V/STOL configuration by incorporating two LCF-459 lift cruise fans and three YJ-97 gas generators. The propulsion concept provides the thrust for horizontal flight or lift for vertical flight by deflection of bifurcated nozzles while maintaining engine out safety throughout the flight envelope. The configuration meets all the study requirements specified for the design with control powers in VTOL and conversion in excess of the requirement making it an excellent vehicle for research and development. The study report consists of two volumes; Volume 1 (Reference a) contains background data detailed description and technical substantiation of the aircraft. Volume 2 includes cost data, scheduling and program planning not addressed in Volume 1

    Exploring how nurses assess, monitor and manage acute pain for adult critically ill patients in the emergency department: Protocol for a mixed methods study

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    © 2017 The Author(s). Background: Many critically ill patients experience moderate to severe acute pain that is frequently undetected and/or undertreated. Acute pain in this patient cohort not only derives from their injury and/or illness, but also as a consequence of delivering care whilst stabilising the patient. Emergency nurses are increasingly responsible for the safety and wellbeing of critically ill patients, which includes assessing, monitoring and managing acute pain. How emergency nurses manage acute pain in critically ill adult patients is unknown. The objective of this study is to explore how emergency nurses manage acute pain in critically ill patients in the Emergency Department. Methods: In this paper, we provide a detailed description of the methods and protocol for a multiphase sequential mixed methods study, exploring how emergency nurses assess, monitor and manage acute pain in critically ill adult patients. The objective, method, data collection and analysis of each phase are explained. Justification of each method and data integration is described. Discussion: Synthesis of findings will generate a comprehensive picture of how emergency nurses' perceive and manage acute pain in critically ill adult patients. The results of this study will form a knowledge base to expand theory and inform research and practice

    Corruption in Uganda: A Comparative Study of Citizens’ and Public Officials’ Perceptions

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    The findings of this study into the complex problem of corruption in Uganda dispel the pervasive and popular view that corruption in East Africa’s third largest economy is an exclusive behavior monopolized by public officials. This study finds that corruption is engendered by an unholy alliance between citizens desperate to access services and public officials eager to exact a price on services they are obliged to freely provide. This study determined that corruption in Uganda largely depends upon collaboration by citizens and public officials, hence changing the simplest meaning of corruption from the abuse of public office to an act that benefits the community. Using the Institutional Analysis and Development framework (IAD), the primary purpose of this quantitative comparative study was to examine to what extent citizens and public officials differed in levels of their perception of corruption and the degree of the forms of corruption in Uganda. Using a survey of 12,000 citizens and 670 public officials, we found that citizens and public officials were slightly different in their perception of corruption, but corruption is a collaborative endeavor involving many behaviors that are discussed in detail. Key recommendations are to adopt technological inter-faces, reduce work incentives, and subject potential candidates to prove suitability before working in public service. Future research agendas are also discussed
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