9,536 research outputs found

    Cost and schedule management on the quiet short-haul research aircraft project

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    The Quiet Short-Haul Research Aircraft (QSRA) Project, one of the largest aeronautical programs undertaken by NASA to date, achieved a significant cost underrun. This is attributed to numerous factors, not the least of which were the contractual arrangement and the system of cost and schedule management employed by the contractor. This paper summarizes that system and the methods used for cost/performance measurement by the contractor and by the NASA project management. Recommendations are made for the use of some of these concepts in particular for future programs of a similar nature

    Annual and solar-magnetic-cycle variations in the interplanetary magnetic field, 1926-1971

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    The analysis of forty-five years of inferred interplanetary magnetic field polarity shows an annual variation and a variation of about twenty years, associated here with the solar magnetic cycle. On the average the phase of the annual variation of the interplanetary field changes about 2 and 2/3 years after sunspot maximum, i.e. for about ten consecutive years the predominant polarity of the interplanetary field is away from the sun during the six-month interval in which the earth is at southern heliographic latitudes. Then a change of phase occurs so that for about the next ten years the predominant polarity is toward the sun, while the earth is at southern heliographic latitudes. The annual variation changes its predominant polarity within a few days of the times when the heliographic latitude of the earth is zero

    A least squares method for the reduction of free-oscillation data

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    Least squares determination of frequency, damping ratio, amplitude, and phase angle from free oscillation dat

    The equatorial rotation velocity of the photosphere is measured to be the same as sunspots

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    The equatorial rotation rate of the photosphere was measured at effect data. It was found that scattered light has a large influence and must be taken into account properly. When this was done it was found that the rotation rate from Doppler shifts agreed very well with the rate found for sunspots. Short-term fluctuations in rotation rate (i.e. from day to day) were less than plus or minus 15 m/s and were thus within observational errors

    DNA fingerprinting analysis of coagulase negative staphylococci implicated in catheter related bloodstream infections

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    AIMS: The epidemiological assessment of cases of coagulase negative staphylococcal catheter related bloodstream infection. METHODS: Two hundred and thirty patients with suspected catheter related bloodstream infection were evaluated over a two year period. Central venous catheters were cultured both endoluminally and extraluminally. Peripheral blood, catheter hubs, skin entry, and skin control sites were also cultured. Pulsed field gel electrophoresis (PFGE) was used to DNA fingerprint coagulase negative staphylococci isolated from patients with presumptive catheter related bloodstream infection. RESULTS: Sixty cases of catheter related bloodstream infection were identified, 21 of which were attributed to coagulase negative staphylococci. Two hundred and ninety four separate isolates of coagulase negative staphylococci from the 21 cases of catheter related bloodstream infection were subjected to PFGE (mean of 14 for each case). Catheter related bloodstream infection was only confirmed by PFGE analysis in 16 of the 21 cases because in the remaining five cases peripheral blood and central venous catheter coagulase negative staphylococci isolates were different. Skin entry, control skin, and central venous catheter hub isolates matched peripheral blood isolates in six, four, and seven cases, respectively. Coagulase negative staphylococci isolates could not be cultured from the patients’ own skin in seven cases of catheter related bloodstream infection. Central venous catheter lumens were colonised in all cases of catheter related bloodstream infection compared with 44–81% of cases that had positive external surface catheter tip cultures, depending on the threshold used to define significant growth. CONCLUSIONS: Catheter related bloodstream infection as a result of coagulase negative staphylococci may be over stated in about a quarter of cases, unless a discriminatory technique is used to fingerprint isolates. No single, simplistic route of bacterial contamination of central venous catheters was identified, but endoluminal catheter colonisation is invariably present in cases of catheter related bloodstream infection. The use of central venous catheters as a means of access for monitoring and as a route of administration of drugs has become almost mandatory in patients with serious illnesses. Infections of central venous catheters are common and coagulase negative staphylococci remain the most frequent pathogens—for example, 37% of 1267 isolates in one meta-analysis.Controversy remains over the source of, and route of access by, these bacteria to the central venous catheters. Recent developments, such as catheters with antimicrobial properties, are an important advance, but until such issues are resolved it remains unclear how best to reduce the risk of catheter related bloodstream infection. “Pulsed field gel electrophoresis is well recognised as the gold standard for fingerprinting coagulase negative staphylococci” Because there are at least 33 distinct coagulase negative staphylococci species that have been identified, and because methods that use phenotyping alone cannot accurately distinguish between strains of coagulase negative staphylococci, DNA fingerprinting is required to clarify the epidemiology of coagulase negative staphylococci catheter related bacterial bloodstream infection. Despite the accepted difficulties in determining the relatedness of coagulase negative staphylococci, diagnostic laboratories routinely rely on limited information from phenotypic tests to compare isolates fro

    A perceived gap between invasive species research and stakeholder priorities

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    Information from research has an important role to play in shaping policy and management responses to biological invasions but concern has been raised that research focuses more on furthering knowledge than on delivering practical solutions. We collated 449 priority areas for science and management from 160 stakeholders including practitioners, researchers and policy makers or advisors working with invasive species, and then compared them to the topics of 789 papers published in eight journals over the same time period (2009–2010). Whilst research papers addressed most of the priority areas identified by stakeholders, there was a difference in geographic and biological scales between the two, with individual studies addressing multiple priority areas but focusing on specific species and locations. We hypothesise that this difference in focal scales, combined with a lack of literature relating directly to management, contributes to the perception that invasive species research is not sufficiently geared towards delivering practical solutions. By emphasising the practical applications of applied research, and ensuring that pure research is translated or synthesised so that the implications are better understood, both the management of invasive species and the theoretical science of invasion biology can be enhanced

    Review of \u3cem\u3eMr. Wuffles\u3c/em\u3e by David Wiesner

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    https://digitalcommons.cedarville.edu/intern_book_reviews/1104/thumbnail.jp

    The Intersection of Politics and Theology: Reading Augustine in Light of Augustine

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    Augustine’s The City of God is a foundational theological text for the development of Christian thought across time. Over the centuries, political scientists and theologians have been especially interested in this text in a variety of ways, but for the purposes of this discussion, the focus will be on Books I-V and Book XIX. Typically, theologians have been interested in Augustine’s rebuttal of pagan claims that are found in the first five books, while political scientists focus most of their attention on Book XIX for its discussion of the highest ends of the state through the means of politics in a context characterized by fallen humanity. Studying the arguments set forth in these two sections independently of one another has proved to produce valuable additions to both theological and political science scholarship; however, by ignoring the other sections, scholars will have a limited understanding of Augustine’s view on the highest good. It is essential to read Books I-V and Book XIX in light of one another because Augustine is filling in the gaps in his own arguments; because The City of God was a work that was developed over thirteen years, it is absolutely necessary for theologians and political scientists to have read both portions of the text, so they are able to understand the full meaning of Augustine’s completed arguments

    Review of \u3cem\u3eCrankee Doodle\u3c/em\u3e by Tom Angleberger

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    https://digitalcommons.cedarville.edu/intern_book_reviews/1103/thumbnail.jp

    Review of \u3cem\u3eA Moose That Says Moooooooooo!\u3c/em\u3e by Jennifer Hamburg

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    https://digitalcommons.cedarville.edu/intern_book_reviews/1102/thumbnail.jp
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