2,470 research outputs found

    Assessment and enhancement of MERRA land surface hydrology estimates

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    The Modern-Era Retrospective Analysis for Research and Applications (MERRA) is a state-of-the-art reanalysis that provides, in addition to atmospheric fields, global estimates of soil moisture, latent heat flux, snow, and runoff for 1979 present. This study introduces a supplemental and improved set of land surface hydrological fields ("MERRA-Land") generated by rerunning a revised version of the land component of the MERRA system. Specifically, the MERRA-Land estimates benefit from corrections to the precipitation forcing with the Global Precipitation Climatology Project pentad product (version 2.1) and from revised parameter values in the rainfall interception model, changes that effectively correct for known limitations in the MERRA surface meteorological forcings. The skill (defined as the correlation coefficient of the anomaly time series) in land surface hydrological fields from MERRA and MERRA-Land is assessed here against observations and compared to the skill of the state-of-the-art ECMWF Re-Analysis-Interim (ERA-I). MERRA-Land and ERA-I root zone soil moisture skills (against in situ observations at 85 U.S. stations) are comparable and significantly greater than that of MERRA. Throughout the Northern Hemisphere, MERRA and MERRA-Land agree reasonably well with in situ snow depth measurements (from 583 stations) and with snow water equivalent from an independent analysis. Runoff skill (against naturalized stream flow observations from 18 U.S. basins) of MERRA and MERRA-Land is typically higher than that of ERA-I. With a few exceptions, the MERRA-Land data appear more accurate than the original MERRA estimates and are thus recommended for those interested in using MERRA output for land surface hydrological studies

    Design, Implementation and Evaluation of a National Campaign to Deliver 18 Million Free Long-Lasting Insecticidal Nets to Uncovered Sleeping Spaces in Tanzania.

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    Since 2004, the Tanzanian National Voucher Scheme has increased availability and accessibility of insecticide-treated nets (ITNs) to pregnant women and infants by subsidizing the cost of nets purchased. From 2008 to 2010, a mass distribution campaign delivered nine million long-lasting insecticidal nets (LLINs) free-of-charge to children under-five years of age in Tanzania mainland. In 2010 and 2011, a Universal Coverage Campaign (UCC) led by the Ministry of Health and Social Welfare (MoHSW) was implemented to cover all sleeping spaces not yet reached through previous initiatives. The UCC was coordinated through a unit within the National Malaria Control Programme. Partners were contracted by the MoHSW to implement different activities in collaboration with local government authorities. Volunteers registered the number of uncovered sleeping spaces in every household in the country. On this basis, LLINs were ordered and delivered to village level, where they were issued over a three-day period in each zone (three regions). Household surveys were conducted in seven districts immediately after the campaign to assess net ownership and use. The UCC was chiefly financed by the Global Fund to Fight AIDS, Tuberculosis and Malaria with important contributions from the US President's Malaria Initiative. A total of 18.2 million LLINs were delivered at an average cost of USD 5.30 per LLIN. Overall, 83% of the expenses were used for LLIN procurement and delivery and 17% for campaign associated activities. Preliminary results of the latest Tanzania HIV Malaria Indicator Survey (2011-12) show that household ownership of at least one ITN increased to 91.5%. ITN use, among children under-five years of age, improved to 72.7% after the campaign. ITN ownership and use data post-campaign indicated high equity across wealth quintiles. Close collaboration among the MoHSW, donors, contracted partners, local government authorities and volunteers made it possible to carry out one of the largest LLIN distribution campaigns conducted in Africa to date. Through the strong increase of ITN use, the recent activities of the national ITN programme will likely result in further decline in child mortality rates in Tanzania, helping to achieve Millennium Development Goals 4 and 6

    The Athabasca University edusource Project: Building An Accessible Learning Object Repository

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    Athabasca University - Canada's Open University (AU) made the commitment to put all of its courses online as part of its Strategic University Plan. In pursuit of this goal, AU participated in the eduSource project, a pan-Canadian effort to build the infrastructure for an interoperable network of learning object repositories. AU acted as a leader in the eduSource work package, responsible for the metadata and standards for learning objects. In addition, the team of professionals, academics, librarians and other researchers worked to create an accessible repository of learning objects across university departments and subjects. Most critically, the team worked beyond the development of a learning object repository and considered the adaptation of content and related applications, pedagogical approaches and the use of learning objects by instructional designers, faculty and the learners themselves. This paper describes one institution's approach to learning object repository development, from a technical and pedagogical perspective, along with some of the lessons learned during the process

    Assessment and Enhancement of MERRA Land Surface Hydrology Estimates

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    The Modern-Era Retrospective analysis for Research and Applications (MERRA) is a state-ofthe-art reanalysis that provides, in addition to atmospheric fields, global estimates of soil moisture, latent heat flux, snow, and runoff for 1979-present. This study introduces a supplemental and improved set of land surface hydrological fields ("MERRA-Land") generated by re-running a revised version of the land component of the MERRA system. Specifically, the MERRA-Land estimates benefit from corrections to the precipitation forcing with the Global Precipitation Climatology Project pentad product (version 2.1) and from revised parameter values in the rainfall interception model, changes that effectively correct for known limitations in the MERRA surface meteorological forcings. The skill (defined as the correlation coefficient of the anomaly time series) in land surface hydrological fields from MERRA and MERRA-Land is assessed here against observations and compared to the skill of the state-of-the-art ERA-Interim (ERA-I) reanalysis. MERRA-Land and ERA-I root zone soil moisture skills (against in situ observations at 85 US stations) are comparable and significantly greater than that of MERRA. Throughout the northern hemisphere, MERRA and MERRA-Land agree reasonably well with in situ snow depth measurements (from 583 stations) and with snow water equivalent from an independent analysis. Runoff skill (against naturalized stream flow observations from 18 US basins) of MERRA and MERRA-Land is typically higher than that of ERA-I. With a few exceptions, the MERRA-Land data appear more accurate than the original MERRA estimates and are thus recommended for those interested in using MERRA output for land surface hydrological studies

    Identifying local innovations in pastoral areas in Marsabit County, Kenya

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    From the cell membrane to the nucleus: unearthing transport mechanisms for Dynein

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    Mutations in the motor protein cytoplasmic dynein have been found to cause Charcot-Marie-Tooth disease, spinal muscular atrophy, and severe intellectual disabilities in humans. In mouse models, neurodegeneration is observed. We sought to develop a novel model which could incorporate the effects of mutations on distance travelled and velocity. A mechanical model for the dynein mediated transport of endosomes is derived from first principles and solved numerically. The effects of variations in model parameter values are analysed to find those that have a significant impact on velocity and distance travelled. The model successfully describes the processivity of dynein and matches qualitatively the velocity profiles observed in experiments

    1St Southern African Students Psychology Conference, Gaborone, Botswana

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    An Integrated TCGA Pan-Cancer Clinical Data Resource to Drive High-Quality Survival Outcome Analytics

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    For a decade, The Cancer Genome Atlas (TCGA) program collected clinicopathologic annotation data along with multi-platform molecular profiles of more than 11,000 human tumors across 33 different cancer types. TCGA clinical data contain key features representing the democratized nature of the data collection process. To ensure proper use of this large clinical dataset associated with genomic features, we developed a standardized dataset named the TCGA Pan-Cancer Clinical Data Resource (TCGA-CDR), which includes four major clinical outcome endpoints. In addition to detailing major challenges and statistical limitations encountered during the effort of integrating the acquired clinical data, we present a summary that includes endpoint usage recommendations for each cancer type. These TCGA-CDR findings appear to be consistent with cancer genomics studies independent of the TCGA effort and provide opportunities for investigating cancer biology using clinical correlates at an unprecedented scale. Analysis of clinicopathologic annotations for over 11,000 cancer patients in the TCGA program leads to the generation of TCGA Clinical Data Resource, which provides recommendations of clinical outcome endpoint usage for 33 cancer types

    Teaching and learning considerations during the COVID 19 pandemic: Supporting multimodal student learning preferences

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    Background. The advent of COVID‑19 and the subsequent national lockdown has catapulted higher education institutions into emergency remote teaching (ERT). A principal challenge in this shift is the ability to stimulate student interest towards engagement with, and retention of, course content. The creation of teaching and learning (T&L) resources and activities using a combination of the visual, aural, read/write and kinaesthetic (VARK) modes is fundamental in ensuring student engagement. Objectives. To determine the learning style profiles of undergraduate students and to explore how student learning profiles may be incorporated in T&L approaches during ERT. Methods. This descriptive study profiles the learning preferences of undergraduate students in a health science faculty using the VARK questionnaire. The study further outlines modifications in T&L implemented to support the varied learning preferences during the COVID‑19 ERT response. Results. Our findings demonstrate that the majority of our students have a multimodal learning preference, with the kinaesthetic modality being the most preferred. Voice-over PowerPoint presentations with transitioning images, and audio files, supported the visual and aural learners through asynchronous engagement. Additionally, online discussion forums and applied projects (such as theme park designs) enhanced asynchronous learning by stimulating the visual, read/write and kinaesthetic preferences, respectively. Microsoft Team sessions with PowerPoint presentations supported visual and aural learning preferences through synchronous engagement. Conclusions. Rethinking traditional T&L approaches towards supporting the diverse student learning preferences is critical in student-centred T&L amidst the many challenges that ERT has precipitated. Academics need to be dynamic in their T&L approaches and intuitive in their awareness of how subject content may be modified/enhanced in the ERT environment
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