9,532 research outputs found

    A geostationary imaging spectrometer TOMS instrument

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    One design for a geostationary Total Ozone Mapping Spectrometer (TOMS) with many desirable features is an imaging spectrometer. A preliminary study makes use of a 0.25 m Czerny-Turner spectrometer with which the Earth is imaged on a charge-coupled device (CCD) in dispersed light. The wavelength is determined by a movable grating which can be set arbitrarily by ground control. The signal integration time depends on wavelength but this system allows arbitrary timing by command. Special circumstances such as a requirement to track a low-lying sulfur dioxide cloud or a need to discriminate high level ozone from total ozone at midlatitudes could be obtained by adding a particular wavelength to the normally pre-programmed time sequence. The incident solar irradiance is measured by deploying a diffuser plate in the field of view. Individual detector elements correspond to scene elements in which the several wavelengths are serially sampled and the Earth radiance is compared to the incident sunlight. Thus the problem of uncorrelated drift of multiple detectors is removed

    Acid catalyzed reactions of alpha and beta styryl azides

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    Acid degradation of alpha and beta styryl azide

    The formation of 3,6-diphenylpyridazine and 2,5-diphenylpyrrole from alpha-styryl azide

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    Formation of 3,6-diphenylpyridazine and 2,5- diphenylpyrrole from alpha-styryl azid

    Experimental observation of the 'Tilting Mode' of an array of vortices in a dilute Bose-Einstein Condensate

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    We have measured the precession frequency of a vortex lattice in a Bose-Einstein condensate of 87Rb atoms. The observed mode corresponds to a collective motion in which all the vortices in the array are tilted by a small angle with respect to the z-axis (the symmetry axis of the trapping potential) and synchronously rotate about this axis. This motion corresponds to excitation of a Kelvin wave along the core of each vortex and we have verified that it has the handedness expected for such helical waves, i.e. precession in the opposite sense to the rotational flow around the vortices. The experimental method used to excite this collective mode closely resembles that used to study the scissors mode and excitation of the scissors mode for a condensate containing a vortex array was used to determine the angular momentum of the system. Indeed, the collective tilting of the array that we have observed has previously been referred to as an `anomalous' scissors mode.Comment: 5 pages, 7 figures to be published in PR

    The core structure of presolar graphite onions

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    Of the ``presolar particles'' extracted from carbonaceous chondrite dissolution residues, i.e. of those particles which show isotopic evidence of solidification in the neighborhood of other stars prior to the origin of our solar system, one subset has an interesting concentric graphite-rim/graphene-core structure. We show here that single graphene sheet defects in the onion cores (e.g. cyclopentane loops) may be observable edge-on by HREM. This could allow a closer look at models for their formation, and in particular strengthen the possibility that growth of these assemblages proceeds atom-by-atom with the aid of such in-plane defects, under conditions of growth (e.g. radiation fluxes or grain temperature) which discourage the graphite layering that dominates subsequent formation of the rim.Comment: 4 pages, 7 figures, 11 refs, see also http://www.umsl.edu/~fraundor/isocore.htm

    Antioxidant Feeding Does Not Impact Incidence or Severity of Liver Abscesses

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    Liver abscesses are a large source of economic loss in feedlot cattle. Not only do liver abscesses lead to a decrease in feedlot performance, but these livers are condemned in the abattoir and can also lead to a further decrease in carcass value due to trim loss. Tylosin phosphate is a metaphylactic macrolide drug that effectively decreases the occurrence of liver abscesses. The drug is approved by the Food and Drug Administration for over-the-counter use. However, in January 2017 the FDA will require a veterinary feed directive for medically important antibiotics (antibiotics that are used in human health) used in production animal feed. Macrolides are one class of antibiotic that will require a veterinary feed directive. A drug that is accompanied by a veterinary feed directive will require it to be used within the regulations that the FDA has set for the specific drug. This new directive is to encourage the animal production industry to use less medically important antibiotics. It is therefore important to look at alternatives to control liver abscesses in feedlot cattle. Various studies have shown that α-tocopherol acetate increases the humoral response and that ascorbate increases mononuclear lymphocyte counts. These antioxidants are also known to maintain the integrity and structure of ruminal papillae, thereby inhibiting pathogenic bacteria that lead to the formation of liver abscesses from gaining access to the portal blood and then eventually the liver. The objective of this study was to evaluate the impact of antioxidants on feedlot performance, carcass characteristics, and incidence and severity of liver abscesses in finishing heifers

    Assessment and diagnosis of Developmental Language Disorder: The experiences of speech and language therapists

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    © The Author(s) 2019. This article is distributed under the terms of the Creative Commons Attribution-NonCommercial 4.0 License (http://www.creativecommons.org/licenses/by-nc/4.0/) which permits non-commercial use, reproduction and distribution of the work without further permission provided the original work is attributed as specified on the SAGE and Open Access pages (https://us.sagepub.com/en-us/nam/open-access-at-sage).Background: For many years research and practice have noted the impact of the heterogeneous nature of Developmental Language Disorder (also known as language impairment or specific language impairment) on diagnosis and assessment. Recent research suggests the disorder is not restricted to the language domain and against this background, the challenge for the practitioner is to provide accurate assessment and effective therapy. The language practitioner aims to support the child and their carers to achieve the best outcomes. However, little is known about the experiences of the language practitioner in the assessment process, in contrast to other childhood disorders, yet their expertise is central in the assessment and diagnosis of children with language disorder. Aims: This study aimed to provide a detailed qualitative description of the experiences of speech and language therapists involved in the assessment and diagnosis of children with Developmental Language Disorder. Methods & Procedures: The qualitative study included three focus groups to provide a credible and rich description of the experiences of speech and language therapists involved in the assessment of Developmental Language Disorder. The speech and language therapists who participated in the study were recruited from three NHS Trusts across the UK and all were directly involved in the assessment and diagnosis procedures. The lengths of practitioner experience ranged from 2 years to 38 years. The data was analysed using a thematic analysis in accordance with the principles set out by Braun & Clarke (2006). Outcomes & Results: The data showed a number of key themes concerning the experiences of speech and language therapists in assessing children with Developmental Language Disorder (DLD). These themes ranged from the participants’ experiences of the barriers to early referral, challenges for assessment and the concerns over continued future support. Conclusions & Implications: This study provides first-hand evidence from speech and language therapists in the assessment of children with Developmental Language Disorder, drawing together experiences from language practitioners from different regions. The findings provide insight to the barriers to referral, the potential variations in the assessment process, the role of practitioner expertise and the challenges faced them. The importance of early intervention, useful assessment tools and future support were expressed. Taken together, the results relate to some issues to be addressed on a practical level and a continuing need for initiatives to raise awareness of DLD in the public domain.Peer reviewe

    Correlation of the Subjective Hip Value with Validated Patient-Reported Outcome Measurements for the Hip

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    Background: The subjective hip value (SHV) was developed as a patient-reported outcome measurement (PROM) that is easily and quickly performed and interpreted. The SHV is defined as a patient's subjective hip measurement tool expressed as a percentage of an entirely normal hip joint, which would score 100%. The hypothesis is that results of the subjective hip value correlate with the results of the modified Harris hip score and the International Hip Outcome Tool in patients with hip-related diseases. Methods: 302 patients completed the modified Harris hip score (mHHS), the International Hip Outcome Tool (iHot-33) as well as the SHV. The SHV consist of only one question: "What is the overall percent value of your hip if a completely normal hip represents 100%?". The patients were divided into five different groups depending on the diagnosis. Pearson correlation was used to evaluate the correlation between the different PROMs and linear regression analysis was used to calculate R2. Results: 302 complete datasets were available for evaluation. There was a high correlation between the SHV and the iHOT-33 (r = 0.847; r2 = 0.692, p < 0.001) and the mHHS (r = 0.832; r2 = 0.717, p < 0.001). The SHV showed a medium (r = 0.653) to high (r = 0.758) correlation with the mHHS and the iHOT-33 in all diagnosis groups. Conclusion: The SHV offers a useful adjunct to established hip outcome measurements, as it is easily and quickly performed and interpreted. The SHV reflects the view of the patient and is independent of the diagnosis. Further research with prospective studies is needed to test the psychometric properties of the score
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