191 research outputs found
An Empirically-Grounded Comparison of the Johnson System versus the Beta as Crop Yield Distribution Models
Previous research established that the expanded Johnson system can accommodate any theoretically possible mean-variance-skewness-kurtosis combination. Therefore, it has been hypothesized that this system can provide for a reasonably accurate modeling approximation of any probability distribution that might be encountered in practice. In order to test that hypothesis, this manuscript develops a more flexible expanded form of the Beta distribution which, in its original form, has been widely used to model and simulate crop yields for risk analysis. Empirically grounded evaluations suggest that the Johnson system can model a variety of typical yield data-generating processes that are based on the Beta distribution much more precisely than the Beta can model representative crop yield data simulated from the Johnson system. The accuracy with which the Johnson system approximates the Beta supports the previously stated hypothesis.Crop Production/Industries,
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Gauging ADA Compliance in the 21st Century Business Internet: A Pilot Study
This paper explores issues of accessibility in Web design, including the applicability of various federal statutes such as the Americans with Disabilities Act of 1990 (ADA) and Section 508 of the Rehabilitation Act of 1973. A pilot study of six private sector websites is completed to gauge the effectiveness of current accessibility standards as interpreted from the ADA and Section 508. Evaluating these sites shows that even after 25 years, sites still have accessibility issues
Developing a Comprehensive, Interdisciplinary Concussion Program
A grant from the One-University Open Access Fund at the University of Kansas was used to defray the author's publication fees in this Open Access journal. The Open Access Fund, administered by librarians from the KU, KU Law, and KUMC libraries, is made possible by contributions from the offices of KU Provost, KU Vice Chancellor for Research & Graduate Studies, and KUMC Vice Chancellor for Research. For more information about the Open Access Fund, please see http://library.kumc.edu/authors-fund.xml.There has been a growing trend of local and national coverage of and interest in concussion injuries over the past 2 decades. Increasing public concern over potential catastrophic and unknown long-term effects of sports-related concussion injuries has led to an acknowledgment of the strong public health need for addressing all concussion injuries, regardless of mechanism of injury. In efforts to address this need for concussion prevention and management, both in sports and nonsports, The University of Kansas Health System initiated the interdisciplinary Center for Concussion Management program in 2012. The program was created as a virtual clinic concept and includes voluntary participation from various providers across the institution, limited budget, and space obstacles. Since its inception, the program has continued to operate as its initial design of a multidisciplinary team model outside the sole ownership of 1 department, and has expanded to include education and outreach to local and regional schools and groups.The University of Kansas (KU) One University Open Access Author Fund sponsored jointly by the KU ProvostKU Vice Chancellor for Research & Graduate Studies, and KUMC Vice Chancellor for Research and managed jointly by the Libraries at the Medical Center and KU - Lawrenc
Have Astronauts Visited Neptune? Student Ideas About How Scientists Study The Solar System
The nature of students’ ideas about the scientific practices used by astronomers when studying objects in our Solar System is of widespread interest to discipline-based astronomy education researchers. A sample of middle-school, high-school, and college students (N=42) in the U.S. were interviewed about how astronomers were able to learn about properties of the Solar System as a follow-up question after specific questions about the nature of the Solar System and its objects. These students often held naive ideas about the practices of astronomy, and 19% of them proposed that humans or robots have returned samples of the planets to Earth for analysis. While the college students provided more sophisticated responses to the questions than the younger students, we found that even they held naive ideas about human sample return and infrequently appealed to studying objects at a distance using telescopes. We propose that students are not receiving specific instruction that allows them to investigate the tools and practices of astronomy, which leads them to rely on their prior knowledge about science practices in other disciplines (e.g., geoscience) when queried about how scientists study the Solar System. This result implies that instruction around the limits of human and robotic spaceflight is needed to allow students to have a more scientific understanding of the practices of astronomy in studying the Solar System
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Prognostic value of different anthropometric indices over different measurement intervals to predict mortality in 6-59-month-old children.
OBJECTIVE: To compare the prognostic value of mid-upper arm circumference (MUAC), weight-for-height Z-score (WHZ) and weight-for-age Z-score (WAZ) for predicting death over periods of 1, 3 and 6 months follow-up in children. DESIGN: Pooled analysis of twelve prospective studies examining survival after anthropometric assessment. Sensitivity and false-positive ratios to predict death within 1, 3 and 6 months were compared for three individual anthropometric indices and their combinations. SETTING: Community-based, prospective studies from twelve countries in Africa and Asia. PARTICIPANTS: Children aged 6-59 months living in the study areas. RESULTS: For all anthropometric indices, the receiver operating characteristic curves were higher for shorter than for longer durations of follow-up. Sensitivity was higher for death with 1-month follow-up compared with 6 months by 49 % (95 % CI (30, 69)) for MUAC < 115 mm (P < 0·001), 48 % (95 % CI (9·4, 87)) for WHZ < -3 (P < 0·01) and 28 % (95 % CI (7·6, 42)) for WAZ < -3 (P < 0·005). This was accompanied by an increase in false positives of only 3 % or less. For all durations of follow-up, WAZ < -3 identified more children who died and were not identified by WHZ < -3 or by MUAC < 115 mm, 120 mm or 125 mm, but the use of WAZ < -3 led to an increased false-positive ratio up to 16·4 % (95 % CI (12·0, 20·9)) compared with 3·5 % (95 % CI (0·4, 6·5)) for MUAC < 115 mm alone. CONCLUSIONS: Frequent anthropometric measurements significantly improve the identification of malnourished children with a high risk of death without markedly increasing false positives. Combining two indices increases sensitivity but also increases false positives among children meeting case definitions
Annexin II Light Chain p11 Interacts With ENaC to Increase Functional Activity at the Membrane
The epithelial Na+ channel (ENaC) provides for Na+ absorption in various types of epithelia including the kidney, lung, and colon where ENaC is localized to the apical membrane to enable Na+ entry into the cell. The degree of Na+ entry via ENaC largely depends on the number of active channels localized to the cell membrane, and is tightly controlled by interactions with ubiquitin ligases, kinases, and G-proteins. While regulation of ENaC endocytosis has been well-studied, relatively little is understood of the proteins that govern ENaC exocytosis. We hypothesized that the annexin II light chain, p11, could participate in the transport of ENaC along the exocytic pathway. Our results demonstrate that all three ENaC channel subunits interacted with p11 in an in vitro binding assay. Furthermore, p11 was able to immunoprecipitate ENaC in epithelial cells. Quantitative mass spectrometry of affinity-purified ENaC-p11 complexes recovered several other trafficking proteins including HSP-90 and annexin A6. We also report that p11 exhibits a robust protein expression in cortical collecting duct epithelial cells. However, the expression of p11 in these cells was not influenced by either short-term or long-term exposure to aldosterone. To determine whether the p11 interaction affected ENaC function, we measured amiloride sensitive Na+ currents in Xenopus oocytes or mammalian epithelia co-expressing ENaC and p11 or a siRNA to p11. Results from these experiments showed that p11 significantly augmented ENaC current, whereas knockdown of p11 decreased current. Further, knockdown of p11 reduced ENaC cell surface population suggesting p11 promotes membrane insertion of ENaC. Overall, our findings reveal a novel protein interaction that controls the number of ENaC channels inserted at the membrane via the exocytic pathway
Clinical care of pregnant and postpartum women with COVID-19: Living recommendations from the National COVID-19 Clinical Evidence Taskforce
To date, 18 living recommendations for the clinical care of pregnant and postpartum women with COVID-19 have been issued by the National COVID-19 Clinical Evidence Taskforce. This includes recommendations on mode of birth, delayed umbilical cord clamping, skin-to-skin contact, breastfeeding, rooming-in, antenatal corticosteroids, angiotensin-converting enzyme inhibitors, disease-modifying treatments (including dexamethasone, remdesivir and hydroxychloroquine), venous thromboembolism prophylaxis and advanced respiratory support interventions (prone positioning and extracorporeal membrane oxygenation). Through continuous evidence surveillance, these living recommendations are updated in near real-time to ensure clinicians in Australia have reliable, evidence-based guidelines for clinical decision-making. Please visit https://covid19evidence.net.au/ for the latest recommendation updates
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