2,336 research outputs found

    Study on the effect of contamination on the performance of X-ray telescopes

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    Modifications were made to the X-ray reflectometer located at the Space Sciences Laboratory, Marshall Space Flight Center. One was an automatic drive for the Large Micrometer Head. This system, interfaced with the Hewlett Packard Computer System, is used to record data and provides the X-ray reflectometer with an automated data-taking capability. Using this system, a complete scatter curve can be obtained automatically. Previously, it was necessary to manually reset the system after recording for each data point in the scatter curve. The second modification provided an externally controlled electrical drive to move the microfocus X-ray source along its axis. With this modification, one can translate the X-ray source while it is operating to locate the position providing maximum count rate

    Pedotransfer functions for Irish soils – estimation of bulk density (ρb) per horizon type

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    This work was conducted as part of the Irish Soil Information System Project, managed by Teagasc (the Irish Agriculture and Food Development Authority) and co-funded by the Environmental Protection Agency (EPA) of Ireland through their Science, Technology, Research and Innovation for the Environment (STRIVE) Programme, as part of the National Development Plan 2007–2013.peer-reviewedSoil bulk density is a key property in defining soil characteristics. It describes the packing structure of the soil and is also essential for the measurement of soil carbon stock and nutrient assessment. In many older surveys this property was neglected and in many modern surveys this property is omitted due to cost both in laboratory and labour and in cases where the core method cannot be applied. To overcome these oversights pedotransfer functions are applied using other known soil properties to estimate bulk density. Pedotransfer functions have been derived from large international data sets across many studies, with their own inherent biases, many ignoring horizonation and depth variances. Initially pedotransfer functions from the literature were used to predict different horizon type bulk densities using local known bulk density data sets. Then the best performing of the pedotransfer functions were selected to recalibrate and then were validated again using the known data. The predicted co-efficient of determination was 0.5 or greater in 12 of the 17 horizon types studied. These new equations allowed gap filling where bulk density data were missing in part or whole soil profiles. This then allowed the development of an indicative soil bulk density map for Ireland at 0–30 and 30–50 cm horizon depths. In general the horizons with the largest known data sets had the best predictions, using the recalibrated and validated pedotransfer functions.Environmental Protection Agenc

    Nachhaltigkeit von drei graslandbasierten Milchproduktionssystemen in der Schweiz mit der Bewertungsmethode RISE

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    Dairy farming is a key sector for Swiss agriculture and the food industry. Therefore, sustainability of dairy farms is important. Grassland-based farming systems are the most common production system, combining the indoor feeding of fresh grass with partial grazing. The effects of three dairy production systems (VW: full grazing plus on avg. 46±93 SD kg concentrate (KF), GFKF: indoor feeding/partial grazing plus on avg. 345±204 SD kg KF and GFKFplus: indoor feeding/partial grazing plus on avg. 1007±353 SD kg KF) on sustainability, according to RISE, were studied on 12 pilot farms in the lowland of Switzerland. In most of the sustainability themes, the farms performed medium to good according to the RISE evaluation scale. The GFKFplus farms produced the highest output of milk by low N- and P-self-sufficiency, showed the highest energy input and the lowest greenhouse gas output per kg milk. The GFKF group achieved remarkable results by moderate N-, P- and energy inputs. The VW farms showed a lower milk output but a higher level of feed self-sufficiency and a lower energy consumption. In the search for the optimal production strategy, farms should consider the individual farm structure (contiguous areas), the market potential but also social aspects such as the preferences of the farmer`s family

    In Search of Modifiable Risk and Protective Factors for Teen Dating Violence

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    Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/137513/1/jora12280_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/137513/2/jora12280.pd

    On Czerwinski's "PNP{\rm P} \neq {\rm NP} relative to a P{\rm P}-complete oracle"

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    In this paper, we take a closer look at Czerwinski's "PNP{\rm P}\neq{\rm NP} relative to a P{\rm P}-complete oracle" [Cze23]. There are (uncountably) infinitely-many relativized worlds where P{\rm P} and NP{\rm NP} differ, and it is well-known that for any P{\rm P}-complete problem AA, PANPA    PNP{\rm P}^A \neq {\rm NP}^A \iff {\rm P}\neq {\rm NP}. The paper defines two sets DP{\rm D}_{\rm P} and DNP{\rm D}_{\rm NP} and builds the purported proof of their main theorem on the claim that an oracle Turing machine with DNP{\rm D}_{\rm NP} as its oracle and that accepts DP{\rm D}_{\rm P} must make Θ(2n)\Theta(2^n) queries to the oracle. We invalidate the latter by proving that there is an oracle Turing machine with DNP{\rm D}_{\rm NP} as its oracle that accepts DP{\rm D}_{\rm P} and yet only makes one query to the oracle. We thus conclude that Czerwinski's paper [Cze23] fails to establish that PNP{\rm P} \neq {\rm NP}

    Structural Studies on Alkylisocyanate Polymers by Thermal Degradation Tandem Mass Spectrometry

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    AbstractHomopolymers and copolymers of alkylisocyanates having n-hexyl, 2,6-dimethylheptyl, 3,7-dimethyloctyl, and (2,2-dimethyl-1,3-dioxolan-4-yl)methyl substituents underwent thermal degradation in the course of desorption electron ionization to yield trimers and monomers that were characterized in situ by tandem mass spectrometry. The trimers were trisubstituted cyanuric acids, the protonated molecules displaying a characteristic series of alkene eliminations on collision-induced dissociation to yield protonated cyanuric acid, m/z 130. Confirmation of the identity of the pyrolysates was obtained by using two types of MS3 experiments: the reaction intermediate scan and the two-dimensional familial scan. The ion chemistry of the trimers and of the protonated monomer, the alkylisocyanate, was elucidated. Among the many interesting fragmentation processes undergone by the ionized trimers were α and β CC bond cleavages and charge-remote fragmentations, which provided information on branching in the alkyl substituent. The dioxolane-containing substituent showed unique ion chemistry. The monomer distribution in the copolymers was deduced from the abundances of the various protonated trimers. The distribution was found to be random in all copolymers except that containing the dioxolane substituent

    Personal protective equipment solution for UK military medical personnel working in an Ebola virus disease treatment unit in Sierra Leone.

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    The combination of personal protective equipment (PPE) together with donning and doffing protocols was designed to protect British and Canadian military medical personnel in the Kerry Town Ebola Treatment Unit (ETU) in Sierra Leone. The PPE solution was selected to protect medical staff from infectious risks, notably Ebola virus, and chemical (hypochlorite) exposure. PPE maximized dexterity, enabled personnel to work in hot temperatures for periods of up to 2h, protected mucosal membranes when doffing outer layers, and minimized potential contamination of the doffing area with infectious material by reducing the requirement to spray PPE with hypochlorite. The ETU was equipped to allow medical personnel to provide a higher level of care than witnessed in many existing ETUs. This assured personnel working as part of the international response that they would receive as close to Western treatment standards as possible if they were to contract Ebola virus disease (EVD). PPE also enabled clinical interventions that are not seen routinely in West African EVD treatment regimens, whilst providing a robust protective barrier. Competency in using PPE was developed during a nine-day pre-deployment training programme. This allowed over 60 clinical personnel per deployment to practice skills in PPE in a simulated ETU and in classrooms. Overall, the training provided: (i) an evidence base underpinning the PPE solution chosen; (ii) skills in donning and doffing of PPE; (iii) personnel confidence in the selected PPE; and (iv) quantifiable testing of each individual's capability to don PPE, perform tasks and doff PPE safely

    Oxidation behavior and microstructural evolution of Ti-6Al-4V and Ti-6Al-4V-1B sheet

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    A direct comparison between the oxidation behavior of Ti-6Al-4V and Ti-6Al-4V + 1B has been conducted to elucidate whether the addition of boron to Ti-6Al-4V impacts the oxidation behavior. Industrially prepared sheet of Ti-6Al-4V and Ti-6Al-4V + 1B were oxidized at temperatures between 650 and 950 °C for holding times of 25 and 50 h. Weight-gain measurements and characterization of surface and near-surface microstructures showed that the addition of 1 wt% B increased the material’s oxidation resistance. Additionally, the ingress of oxygen tends to decrease the solubility of other alloying species in α-Ti and leads to the formation of a distinctive and atypical microstructure with a distinct morphology
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