2,196 research outputs found

    Annual Solar Irradiation Mapping and Visualization for Complex Geometries

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    We introduce an innovative approach to producing an- nual solar irradiation data for complex geometries in urban settings. The method uses advanced ray-tracing and ambient sampling approaches with cumulative sky models derived from hourly climate data. In contrast to earlier approaches that have produced annual irradi- ation maps in the form of images from pre-selected viewing points, this method produces results for all the surfaces of the scene simultaneously. In this approach polygon surface meshes are derived from imported building and terrain digital models. Irradiance are calculated at mesh vertices by making use of Radi- ance software tools. This hybrid ray-tracing and statistical sampling analysis allows inter-reflection between and obscuration by other surfaces to be accounted for with high fidelity. The resulting polygon and irradiance data sets are combined to form 3D models for interactive visualization. The method has a number of advantages over existing image-based approaches and is capable of being applied to detailed study of building designs and larger scale urban scenes

    Inorganic nitrogen and glucose additions alter the short-term formation efficiency of mineral associated organic matter carbon

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    Carbon within mineral associated organic matter (MAOM) is an important persistent form of soil organic carbon (SOC). However, processes driving the retention of new labile C in MAOM are not fully understood. We investigated the effects of glucose and ammonium nitrate (AN) addition on the short-term (72 h) retention of applied 13C-glucose within MAOM. We found an interactive effect of AN addition with the glucose addition rate. Higher rates of glucose addition resulted in proportionally less glucose-C retained, indicating lower MAOM-C formation efficiency. Addition of AN only altered the proportional retention of glucose where glucose was applied at the lowest rate. In this instance glucose-13C recovery increased with AN addition. However, after 72 h there was no treatment difference in total MAOM-C, indicating that any changes in formation efficiency as a result of AN and glucose additions, did not result in differences in total MAOM-C in the short-term. Whether and how this affects the medium and longer-term dynamics of MAOM-C requires further investigation

    WISE J064336.71-022315.4: A Thick Disk L8 Gaia DR2-Discovered Brown Dwarf at 13.9 Parsecs

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    While spectroscopically characterizing nearby ultracool dwarfs discovered in the Gaia Second Data Release with the TripleSpec spectrograph on the Palomar 200'' telescope, we encountered a particularly cool, nearby, new member of the solar neighborhood: Gaia DR2 3106548406384807680 = WISE J064336.71-022315.4 = 2MASS J06433670-0223130. The Gaia\it{Gaia} parallax corresponds to a distance of 13.9 ±\pm 0.3 pc. Using our TripleSpec spectrum we classify W0643 as spectral type L8, and measured a heliocentric radial velocity of 142 ±\pm 12 km s−1^{-1}. When combined with Gaia\it{Gaia} astrometry, we determine a Galactic velocity (heliocentric; UU towards Galactic center) of U,V,WU, V, W = -109, -91, -12 (±\pm10, 5, 3) km s−1^{-1}. We estimate that W0643 passed within ∼\sim1.4 pc away from the Sun ∼\sim100,000 years ago

    Pre-main-sequence isochrones - III: The Cluster Collaboration isochrone server

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    We present an isochrone server for semi-empirical pre-main-sequence model isochrones in the following systems: Johnson–Cousins, Sloan Digital Sky Survey, Two-Micron All-Sky Survey, Isaac Newton Telescope (INT) Wide-Field Camera and INT Photometric Hα Survey (IPHAS)/UV-Excess Survey (UVEX). The server can be accessed via the Cluster Collaboration webpage http://www.astro.ex.ac.uk/people/timn/isochrones/. To achieve this, we have used the observed colours of member stars in young clusters with well-established age, distance and reddening to create fiducial loci in the colour–magnitude diagram. These empirical sequences have been used to quantify the discrepancy between the models and data arising from uncertainties in both the interior and atmospheric models, resulting in tables of semi-empirical bolometric corrections (BCs) in the various photometric systems. The model isochrones made available through the server are based on existing stellar interior models coupled with our newly derived semi-empirical BCs. As part of this analysis, we also present new cluster parameters for both the Pleiades and Praesepe, yielding ages of 135+20−11 and 665+14−7Myr as well as distances of 132 ± 2 and 184 ± 2 pc, respectively (statistical uncertainty only)

    Pre-main-sequence isochrones - III. The cluster collaboration isochrone server

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    We present an isochrone server for semi-empirical pre-main-sequence model isochrones in the following systems: Johnson-Cousins, Sloan Digital Sky Survey, Two-Micron All-Sky Survey, Isaac Newton Telescope (INT) Wide-Field Camera and INT Photometric Ha Survey (IPHAS)/UV-Excess Survey (UVEX). The server can be accessed via the Cluster Collaboration webpage http://www.astro.ex.ac.uk/people/timn/isochrones/. To achieve this, we have used the observed colours ofmember stars in young clusters with well-established age, distance and reddening to create fiducial loci in the colour-magnitude diagram. These empirical sequences have been used to quantify the discrepancy between the models and data arising from uncertainties in both the interior and atmospheric models, resulting in tables of semi-empirical bolometric corrections (BCs) in the various photometric systems. The model isochrones made available through the server are based on existing stellar interior models coupled with our newly derived semi-empirical BCs. As part of this analysis, we also present new cluster parameters for both the Pleiades and Praesepe, yielding ages of 135+20 -11 and 665+14 -7 Myr as well as distances of 132 ± 2 and 184 ± 2 pc, respectively (statistical uncertainty only).JMR is funded by a UK Science and Technology Facilities Council (STFC) studentship. EEM acknowledges support from the National Science Foundation (NSF) Award AST-1008908. The authors would like to thank Emanuele Tognelli for the updated set of Pisa models and John Stauffer for sharing his catalogue of Kron photometric measurements of Pleiades members. The authors would also like to thank the referee for comments which have vastly improved the clarity of the manuscript. This research has made use of data obtained at the Isaac Newton Telescope, which is operated on the island of La Palma by the Isaac Newton Group (ING) in the Spanish Observatorio del Roque de los Muchachos of the Institutio de Astrofisica de Canarias. This research has made use of archival data products from the Two-Micron All-Sky Survey (2MASS), which is a joint project of the University of Massachusetts and the Infrared Processing and Analysis Center, funded by the National Aeronautics and Space Administration (NASA) and the National Science Foundation. This research has made use of public data from the SDSS. Funding for the SDSS was provided by the Alfred P. Sloan Foundation, the Participating Institutions, the National Science Foundation, the US Department of Energy, the National Aeronautics and Space Administration, the Japanese Monbukagakusho, the Max Planck Society and the Higher Education Funding Council for England. The SDSS was managed by the Astrophysical Research Consortium for the Participating Institutions

    The Newcastle ENDOPREMâ„¢: a validated patient reported experience measure for gastrointestinal endoscopy

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    OBJECTIVES: Measuring patient experience of gastrointestinal (GI) procedures is a key component of evaluation of quality of care. Current measures of patient experience within GI endoscopy are largely clinician derived and measured; however, these do not fully represent the experiences of patients themselves. It is important to measure the entirety of experience and not just experience directly during the procedure. We aimed to develop a patient-reported experience measure (PREM) for GI procedures. DESIGN: Phase 1: semi-structured interviews were conducted in patients who had recently undergone GI endoscopy or CT colonography (CTC) (included as a comparator). Thematic analysis identified the aspects of experience important to patients. Phase 2: a question bank was developed from phase 1 findings, and iteratively refined through rounds of cognitive interviews with patients who had undergone GI procedures, resulting in a pilot PREM. Phase 3: patients who had attended for GI endoscopy or CTC were invited to complete the PREM. Psychometric properties were investigated. Phase 4 involved item reduction and refinement. RESULTS: Phase 1: interviews with 35 patients identified six overarching themes: anxiety, expectations, information & communication, embarrassment & dignity, choice & control and comfort. Phase 2: cognitive interviews refined questionnaire items and response options. Phase 3: the PREM was distributed to 1650 patients with 799 completing (48%). Psychometric properties were found to be robust. Phase 4: final questionnaire refined including 54 questions assessing patient experience across five temporal procedural stages. CONCLUSION: This manuscript gives an overview of the development and validation of the Newcastle ENDOPREMâ„¢, which assesses all aspects of the GI procedure experience from the patient perspective. It may be used to measure patient experience in clinical care and, in research, to compare patients' experiences of different endoscopic interventions
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