172 research outputs found

    Alternative polarisation retrieval for SCIAMACHY in the ultraviolet

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    International audienceWe introduce an alternative method for the retrieval of polarisation in the ultraviolet by the satellite spectrometer SCIAMACHY. Unlike the operational polarisation retrieval algorithm, this method does not use the Polarisation Measurement Devices (PMDs) onboard SCIAMACHY, but only requires the reflectance signal. This makes the algorithm more robust and less sensitive to calibration errors caused by either improper characterisation of the instrument's response functions (key data) or degradation of the optical components. The alternative polarisation retrieval is able to retrieve the full state of atmospheric polarisation in the wavelength range between 330 and 400 nm, which is essentially the wavelength region covered by SCIAMACHY's PMD 1. This allows a direct comparison with the current operational product. When we compare the alternative polarisation algorithm with the operational algorithm, we find in some cases agreement, but not in other cases. The alternative algorithm compares well with an analytical model of the polarisation of a cloud-free scene. Using the alternative algorithm the polarisation-sensitive feature in the SCIAMACHY reflectance around 350 nm is automatically corrected for

    Large-scale validation of SCIAMACHY reflectance in the ultraviolet

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    In this paper we present an extensive validation of calibrated SCIAMACHY nadir reflectance in the UV (240-400 nm) by comparison with spectra calculated with a fast radiative transfer model. We use operationally delivered near-real-time level 1 data, processed with standard calibration tools. A total of 9 months of data has been analysed. This is the first reflectance validation study incorporating such a large amount of data. It is shown that this method is a valuable tool for spotting spatial and temporal anomalies. We conclude that SCIAMACHY reflectance data in this wavelength range are stable over the investigated period. In addition, we show an example of an anomaly in the data due to an error in the processing chain that could be detected by our comparison. This validation method could be extremely useful too for validation of other satellite spectrometers, such as OMI and GOME-2

    Instructing Students How to Use Evidence-based Technology Interventions with Older Adults

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    Current evidence supports the use of technology with older adults and the Accreditation Council for Occupational Therapy Education standards for entry-level occupational therapy programs mandate instruction on the use of technology to support occupational performance. The literature does not clearly define specific strategies to teach entry-level occupational therapy students how to implement technology interventions with older adults. The purpose of this paper is to provide OT educators with recommendations for teaching entry-level students to use evidence-based technology with older adults. The authors reviewed current literature. The recent evidence helped the authors define practical curriculum recommendations for instructing entry-level occupational therapy students to integrate technology into older adults’ interventions. Recommendations include use of telehealth visits, teleconferencing, iPad applications, smart phone applications, texting, emails, and video applications. With technology continually changing, occupational therapy instructors must increase their awareness of new applications and computer programs that occupational therapists can utilize in older adult interventions to maximize knowledge translation to their students

    Contiguous polarisation spectra of the Earth from 300 to 850 nm measured by GOME-2 onboard MetOp-A

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    In this paper we present the first contiguous high-resolution spectra of the Earth's polarisation observed by a satellite instrument. The measurements of the Stokes fraction <i>Q/I</i> are performed by the spectrometer GOME-2 onboard the MetOp-A satellite. Polarisation measurements by GOME-2 are performed by onboard polarisation measurement devices (PMDs) and the high-resolution measurements discussed in this paper are taken in the special "PMD RAW" mode of operation. The spectral resolution of these PMD RAW polarisation measurements varies from 3 nm in the ultraviolet (UV) to 35 nm in the near-infrared wavelength range. We first compare measurements of the polarisation from cloud-free scenes with radiative transfer calculations for a number of cases. We find good agreement but also a spectral discrepancy at 800 nm, which we attribute to remaining imperfections in the calibration key data. Secondly, we study the polarisation of scenes with special scattering geometries that normally lead to near-zero <i>Q/I</i>. The GOME-2 polarisation spectra indeed show this behaviour and confirm the existence of the small discrepancy found earlier. Thirdly, we study the Earth polarisation for a variety of scenes. This provides a blueprint of <i>Q/I</i> over land and sea surfaces for various degrees of cloud cover. Fourthly, we compare the spectral dependence of measurements of <i>Q/I</i> in the UV with the generalised distribution function proposed by Schutgens and Stammes (2002) to describe the shape of the UV polarisation spectrum. The GOME-2 data confirm that these functions match the spectral behaviour captured by the GOME-2 PMD RAW mode

    In-flight degradation correction of SCIAMACHY UV reflectances and Absorbing Aerosol Index

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    In this paper we study the close relationship between the radiometric calibration of a satellite instrument and the Absorbing Aerosol Index (AAI) derived from the observed Earth reflectance. Instrument degradation of the Scanning Imaging Absorption Spectrometer for Atmospheric Chartography (SCIAMACHY) instrument in the ultraviolet wavelength range is examined by analyzing time series of global means of the AAI, making use of the experience that the global mean should be more or less constant when instrument degradation is absent. The analysis reveals the magnitude of the (scan angle dependent) instrument degradation of SCIAMACHY and also shows that currently available correction techniques are not able to correct the instrument degradation in a sufficient manner. We therefore develop and introduce a new method for degradation correction, which is based on the analysis of the time evolution of the global mean reflectance. Seasonal variations in the global mean reflectance, which mainly result from seasonal variations in scattering geometry and global cloud coverage, are separated from the time series in order to isolate the instrument degradation. Finally, we apply the derived reflectance correction factors to the SCIAMACHY reflectances and calculate the AAI to find that the effects of instrument degradation are reduced to within the 0.1 index point level. The derived AAI is also compared with the AAI based on other correction techniques. The proposed in-flight reflectance degradation correction method performs best in all aspects. © 2012 by the American Geophysical Union

    Cultural Competence with Humility Using Interprofessional Multicultural Learning Activities: Student Perceptions

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    This study examined students’ perceptions of interprofessional multicultural learning activities used to develop cultural competence with humility (CCH). Limited research exists on student perceptions of learning activities for CCH in entry-level occupational therapy educational programs. This exploratory, mixed methods study used an anonymous online survey, the Learning Activities Survey (LAS), to collect student quantitative ratings and qualitative feedback about CCH learning activities and their experience within the Counselors and Occupational Therapists Professionally Engaged in the Community (COPE) program. A deductive thematic approach was used by two investigators for qualitative analyses of COPE learning activities by alignment in four a priori CCH constructs: cultural awareness, cultural knowledge, cultural skills, and cultural desire. Consensus was gained through discussion. Nineteen of 29 (65.5%) students completed the survey. The mean score on the LAS for 6 of 12 activities (50%) was at least Moderately important (mean ≥ 3.0) to student learning. Twelve of 19 students (63%) rated 11 of 12 learning activities as Moderately important (mean ≥ 3.0). Qualitatively, cognitive knowledge was the strongest reported CCH learning construct within the COPE program with a frequency of 32. The combined quantitative and qualitative responses indicated the learning activities positively influenced students’ learning of CCH. This study may inform occupational therapy curricular activities that satisfy accreditation requirements and expectations of the profession to meet the cultural needs of society. It also provides support for revisions to occupational therapy educational program standards to better align with recent literature

    Sex and Gender-Based Women\u27s Health: A Practical Guide for Primary Care - A Resource for Learning and Teaching

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    TOP WINNER Background: Patients expect comprehensive, gender-specific care; yet studies reveal that few residency programs in internal medicine provide dedicated training in women’s health and gender-based medicine. Further, graduates are unable to demonstrate competency to care for female and gender-diverse patients. Objectives: To produce a sex and gender-based women’s health curriculum, written explicitly for primary care providers to guide the care of women and gender-diverse patients, and to be used as a curriculum to educate learners. Methods: In collaboration with Springer Nature, development of this online and inprint textbook began in 2017. Topics were chosen with input from women’s health experts and are tailored to gender-based conditions commonly evaluated, diagnosed, and/or managed in the primary care setting. Authors were then recruited nationally for each topic. Using evidenced-based medicine principles, chapters were formatted for consistency to include the epidemiology, physiology/pathophysiology, clinical manifestations, differential diagnosis, diagnostic approach, and treatment for each topic, when appropriate. Each chapter has clear, measurable learning objectives, summary statements, and multiplechoice questions with annotated answers to check understanding and help earn CME and MOC credit. With 39 chapters and \u3e600 pages, sections are comprehensive and include Breast and Gynecologic Health and Disease, Obstetric Medicine, Chronic Pain Disorders, Mental Health and Trauma, LGBTQ Health, Common Medical Conditions (osteoporosis, cardiovascular disease), and Foundations of Women’s Health, which highlights the history, disparities, and future of women’s and gender-based healthcare. Conclusions/Impact: This is the first comprehensive curricular resource written by clinical women’s health physicians, using the most up-to-date evidence, clinical guidelines, expert opinion, and clinical pearls. Our goal is to provide a guide that can serve as a quick point-of-care clinical reference for a specific topic or as a longitudinal curriculum for learners in any primary care discipline, especially programs where women’s health and gender-specific curricula and champions are sparse.https://jdc.jefferson.edu/sexandgenderhealth/1030/thumbnail.jp
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