7,693 research outputs found

    IECM calibration and data reduction requirements

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    The induced environment contamination monitor (IECM) tape recorder format, as it relates to the ouput of meaningful data from the IECM instrument, is explained. Eight-bit words (or bytes) generate numbers that represent voltage levels of electronic detection probes for each experiment. This information is amalgamated by the IECM Data Acquisition and Control System (DACS). In some cases bits represent certain status situations concerning an experiment, such as whether a valve is opened or closed. Voltages are transformed into meaningful physical phenomena through equations of calibration. Data formats and plots are generated as requested for each IECM experimenter

    Inelastic neutron scattering studies of the quantum frustrated magnet clinoatacamite, γ\gamma-Cu2(OD)3Cl, a proposed valence bond solid (VBS)

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    The frustrated magnet clinoatacamite, γ\gamma-Cu2_2(OH)3_3Cl, is attracting a lot of interest after suggestions that at low temperature it forms an exotic quantum state termed a Valence Bond Solid (VBS) made from dimerised Cu2+^{2+} (S=1/2S=1/2) spins.\cite{Lee_clinoatacamite} Key to the arguments surrounding this proposal were suggestions that the kagom\'e planes in the magnetic pyrochlore lattice of clinoatacamite are only weakly coupled, causing the system to behave as a quasi-2-dimensional magnet. This was reasoned from the near 95^\circ angles made at the bridging oxygens that mediate exchange between the Cu ions that link the kagom\'e planes. Recent work pointed out that this exchange model is inappropriate for γ\gamma-Cu2_2(OH)3_3Cl, where the oxygen is present as a μ3\mu_3-OH.\cite{Wills_JPC} Further, it used symmetry calculations and neutron powder diffraction to show that the low temperature magnetic structure (T<6T<6 K) was canted and involved significant spin ordering on all the Cu2+^{2+} spins, which is incompatible with the interpretation of simultaneous VBS and N\'eel ordering. Correspondingly, clinoatacamite is best considered a distorted pyrochlore magnet. In this report we show detailed inelastic neutron scattering spectra and revisit the responses of this frustrated quantum magnet.Comment: Proceedings of The International Conference on Highly Frustrated Magnetism 2008 (HFM2008

    Reference amounts utilised in front of package nutrition labelling:impact on product healthfulness evaluations

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    Background/Objectives: The research question addressed in this paper is how different reference amounts utilised in front of package nutrition labelling influence evaluation of product healthfulness. Subjects/Methods: A total of 13 117 participants from six European countries (Germany, UK, Spain, France, Poland and Sweden) were recruited via online panels. A mixed between/within-subject factorial design was employed with food (biscuits, sandwiches, yogurts), healthfulness and presence of Guideline Daily Amounts as within-subjects factors and reference amount (‘per 100 g’, ‘typical portion’, ‘half portion’) and country as between-subjects factors. Results: Overall, people correctly ranked foods according to their objective healthfulness as defined by risk nutrients alone, and could distinguish between more and less healthful variants of foods. General healthfulness associations with the three product categories do not appear to have had a strong influence on product ratings. This study shows that where the reference amount of ‘per 100 g’ is very different from the ‘typical’ portion size, as was the case for biscuits, products with a ‘per 100 g’ label are rated significantly less healthful than the ‘typical’ or ‘half typical’ portions. Conclusion: The results indicate that across the three food categories, consumers do factor the reference amount, that is, the quantity of food for which the nutritional information is being presented, into their judgements of healthfulness. Therefore, appropriate reference amounts are also of importance for the effective presentation of nutritional information

    The Reproductive Season of the Highland Stoneroller, Campostoma spadiceum, Evidenced by Museum Specimens

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    The Highland Stoneroller (Campostoma spadiceum) was described as a distinct species in 2010. Since then, the only study specific to this species is a survey of distribution, and nothing is known about reproduction. We examined 134 lots including 315 specimens of C. spadiceum housed in the Henderson State University collection of fishes to evaluate the timing of reproductive events. We dissected individuals to reveal sex and reproductive status. Females as small as 49 mm total length were able to yolk eggs, and follicles were in development by October. Ripe eggs were present in specimens collected from January through May, but were most common in March through May. Several females had oviposited in early March, but most specimens that appeared to have spawned had done so likely in April. Nuptial tubercles appeared on males as early as January and February, but most adult males were fully tubercled from March through May
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