3,841 research outputs found

    Combining social network analysis and the NATO Approach Space to define agility. Topic 2: networks and networking

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    This paper takes the NATO SAS-050 Approach Space, a widely accepted model of command and control, and gives each of its primary axes a quantitative measure using social network analysis. This means that the actual point in the approach space adopted by real-life command and control organizations can be plotted along with the way in which that point varies over time and function. Part 1 of the paper presents the rationale behind this innovation and how it was subject to verification using theoretical data. Part 2 shows how the enhanced approach space was put to use in the context of a large scale military command post exercise. Agility is represented by the number of distinct areas in the approach space that the organization was able to occupy and there was a marked disparity between where the organization thought it should be and where it actually was, furthermore, agility varied across function. The humans in this particular scenario bestowed upon the organization the levels of agility that were observed, thus the findings are properly considered from a socio-technical perspective

    The Use of Breast Cup Immobilization in Radiation Therapy and Patient Reported Outcomes on Cosmesis and Pain

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    Purpose/Objective(s): Breast cosmesis and pain are among the most reported outcomes in patients undergoing breast irradiation. There is variability in the degree of adverse reactions based on different patient specific characteristics. It has been found that women with large body habitus, African American race, and larger breast size tend to have an increased chance of experiencing worse toxicity from treatment. Attempts to improve cosmesis and pain have been highly explored. We explore here whether the use of a breast cup for treatment leads to worse cosmesis and pain when compared to those treated without a breast cup. This is an important topic as it is felt that the use of a breast cup would provide a significant dosimetric advantage (i.e., organ at risk dosing) during treatment. We now explore this treatment option through a retrospective analysis of patient reported outcomes experienced during and after completing post-operative radiation therapy to the breast. Materials/Methods: 645 patients undergoing adjuvant breast irradiation were evaluated from 2011 through 2019. 79 patients were treated using a breast cup. Mean heart dose was analyzed and compared between the two treatment groups and was found to be comparable in each arm. Additionally, patient reported outcomes among the entire cohort were collected via survey documentation forms during treatment, at 1 month post treatment, and at 1 year after treatment. These results were collected using the Michigan Radiation Oncology Quality Consortium (MROQC) database as each patient was consented to enroll in MROQC prior to starting treatment. The outcomes of skin changes, lymphedema, and breast pain among the two treatment groups were then compared for statistically significant differences via a logistic regression analysis. Results: Patients were evaluated at 3 time points; during treatment, 1-month post-treatment and at 1 year after treatment. Of the 79 patients treated with a breast cup, when compared to the no cup patients, grade 2 pruritus and grade 1 alteration in skin texture were not significantly different at any time point (p \u3e 0.05). With regards to lymphedema, no statistically significant difference was seen between the two groups of patients outside of the 1 month after treatment survey time point; all p values greater than 0.05 except for the 1-month mark (p value 0.03). Lastly, breast pain survey remarks at the pre-specified time points failed to show a significant difference in the symptom between the two analyzed treatment groups (p\u3e 0.05). Conclusion: From our patient\u27s perspective, the use of a breast cup during radiation therapy did not negatively impact breast cosmesis or pain when compared to patients treated without a cup. Breast cup use was also found to produce similar dosimetric coverage to the heart as non-cup patients, even in left sided breast cancers

    Spin Waves in Detwinned BaFe2_2As2_2

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    Understanding magnetic interactions in the parent compounds of high-temperature superconductors forms the basis for determining their role for the mechanism of superconductivity. For parent compounds of iron pnictide superconductors such as AAFe2_2As2_2 (A=A= Ba, Ca, Sr), although spin excitations have been mapped out throughout the entire Brillouin zone (BZ), measurements were carried out on twinned samples and did not allow for a conclusive determination of the spin dynamics. Here we use inelastic neutron scattering to completely map out spin excitations of ∼\sim100\% detwinned BaFe2_2As2_2. By comparing observed spectra with theoretical calculations, we conclude that the spin excitations can be well described by an itinerant model with important contributions from electronic correlations.Comment: 6 pages, 4 figures, with supplemental materia

    Where do we go from here? An assessment of navigation performance using a compass versus a GPS unit

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    The Global Positioning System (GPS) looks set to replace the traditional map and compass for navigation tasks in military and civil domains. However, we may ask whether GPS has a real performance advantage over traditional methods. We present an exploratory study using a waypoint plotting task to compare the standard magnetic compass against a military GPS unit, for both expert and non-expert navigators. Whilst performance times were generally longer in setting up the GPS unit, once navigation was underway the GPS was more efficient than the compass. For mediumto long-term missions, this means that GPS could offer significant performance benefits, although the compass remains superior for shorter missions. Notwithstanding the performance times, significantly more errors, and more serious errors, occurred when using the compass. Overall, then, the GPS offers some clear advantages, especially for non-expert users. Nonetheless, concerns over the development of cognitive maps remain when using GPS technologies

    Recent Improvements to the Acoustical Testing Laboratory at the NASA Glenn Research Center

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    The Acoustical Testing Laboratory (ATL) consists of a 27 by 23 by 20 ft (height) convertible hemi/anechoic chamber and separate sound-attenuating test support enclosure. Absorptive fiberglass wedges in the test chamber provide an anechoic environment down to 100 Hz. A spring-isolated floor system affords vibration isolation above 3 Hz. These specifications, along with very low design background levels, enable the acquisition of accurate and repeatable acoustical measurements on test articles that produce very low sound pressures. Removable floor wedges allow the test chamber to operate in either a hemi-anechoic or anechoic configuration, depending on the size of the test article and the specific test being conducted. The test support enclosure functions as a control room during normal operations. Recently improvements were accomplished in support of continued usage of the ATL by NASA programs including an analysis of the ultra-sonic characteristics. A 3 dimensional traverse system inside the chamber was utilized for acquiring acoustic data for these tests. The traverse system drives a linear array of 13, 1/4"-microphones spaced 3" apart (36" span). An updated data acquisition system was also incorporated into the facility

    A Cure for HIV Infection: "Not in My Lifetime" or "Just Around the Corner"?

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    With the advent and stunning success of combination antiretroviral therapy (ART) to prolong and improve quality of life for persons with HIV infection, HIV research has been afforded the opportunity to pivot towards studies aimed at finding "a cure." The mere idea that cure of HIV might be possible has energized researchers and the community towards achieving this goal. Funding agencies, both governmental and private, have targeted HIV cure as a high priority; many in the field have responded to these initiatives and the cure research agenda is robust. In this "salon" two editors of Pathogens and Immunity, Michael Lederman and Daniel Douek ask whether curing HIV is a realistic, scalable objective. We start with an overview perspective and have asked a number of prominent HIV researchers to add to the discussion
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