3,356 research outputs found
Reporting of conflicts of interest in oral presentations at medical conferences : a delegate-based prospective observational study
Ā© Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.Peer reviewedPublisher PD
Holocene-Neogene volcanism in northeastern Australia: chronology and eruption history
Quaternary and late Neogene volcanism is widespread in northeastern Australia, producing at least 397 eruptions covering more than 20,000 km2, including at least 20 flows over 50 km long. Despite this abundance of young volcanism, before this study numerous eruptions had tentative ages or were undated, and the area requires a comprehensive evaluation of eruption patterns through time. To help address these issues we applied multi-collector ARGUS-V 40Ar/39Ar geochronology to determine the age of four of the younger extensive flows: Undara (160 km long, 189 Ā± 4/4 ka; 2Ļ, with full analytical/external uncertainties), Murronga (40 km long, 153 Ā± 5/5 ka), Toomba (120 km long, 21 Ā± 3/3 ka), and Kinrara (55 km long, 7 Ā± 2/2 ka). Verbal traditions of the Gugu Badhun Aboriginal people contain features that may potentially describe the eruption of Kinrara. If the traditions do record this eruption, they would have been passed down for 230 Ā± 70 generations ā a period of time exceeding the earliest written historical records. To further examine north Queensland volcanism through time we compiled a database of 337 ages, including 179 previously unpublished K-Ar and radiocarbon results. The compiled ages demonstrate that volcanic activity has occurred without major time breaks since at least 9 Ma. The greatest frequency of eruptions occurred in the last 2 Ma, with an average recurrence interval of <10ā22 ka between eruptions. Activity was at times likely more frequent than these calculations indicate, as the geochronologic dataset is incomplete, with undated eruptions, and intraplate volcanism is often episodic. The duration, frequency, and youthfulness of activity indicate that north Queensland volcanism should be considered as potentially still active, and there are now two confirmed areas of Holocene volcanism in eastern Australia ā one at each end of the continent. More broadly, our data provides another example of 40Ar/39Ar geochronology applied to Holocene and latest Pleistocene mafic eruptions, further demonstrating that this method has the ability to examine eruptions and hazards at the youngest volcanoes on Earth
Structural Reliability Assessment of Safety Factors for Unreinforced Masonry Veneer Walls Subjected to Out-of-plane Loading
Structural Reliability Assessment of Safety Factors for Unreinforced Masonry Veneer Walls Subjected to Out-of-plane Loading
Challenges of Engaging Local Stakeholders for Statewide Program Development Process
The University of Missouri Extension needed to develop an annual program review process that collaboratively engaged county-level stakeholders. The results from the first 2 years highlight the results, challenges, and implications of the design process. The annual review process needs to be adaptive, responsive, and reflective from year to year when engaging with local stakeholders. For example, the 2012 program review process changed from the prior year to focus on participant mind mapping to better engaged stakeholders and to produces more detailed data. The process has ensured more engagement with local stakeholders and generated information helpful to regional faculty members
Effects of secondary metal carbonate addition on the porous character of resorcinol-formaldehyde xerogels
A deeper understanding of the chemistry and physics of growth, aggregation and gelation processes involved in the formation of xerogels is key to providing greater control of the porous characteristics of such materials, increasing the range of applications for which they may be utilised. Time-resolved dynamic light scattering has been used to study the formation of resorcinol-formaldehyde gels in the presence of combinations of Group I (Na and Cs) and Group II (Ca and Ba) metal carbonates. It was found that the combined catalyst composition, including species and times of addition, is crucial in determining the end properties of the xerogels, via its effect on growth of clusters involved in formation of the gel network. Combination materials have textural characteristics within the full gamut offered by each catalyst alone; however, in addition, combination materials which retain the small pores associated with sodium carbonate catalysed xerogels exhibit a narrowing of the pore size distribution, providing an increased pore volume within an application-specific range of pore sizes. We also show evidence of pore size tunability while maintaining ionic strength, which significantly increases the potential of such systems for biological applications
Allozyme variation amongst populations of the freshwater crab, Potamonautes perlatus (Decapoda: Potamonautidae) in the Berg River system, Western Cape
The Cape river crab,Ā Potamonautes perlatus,Ā is widely distributed in streams and rivers of the Western Cape where it exhibits considerable morphological variation. Recent genetic work on populations in the Olifants River system has demonstrated the existence of a new cryptic species of river crab, while populations ofĀ P. perlatusĀ in the nearby Berg River system remained uninvestigated. Six populations ofĀ P. perlatusĀ were collected from along the length of the Berg River system (125 km) and the genetic structure was investigated using allozyme electrophoresis. Results from 14 allozyme loci showed that the populations were genetically invariant across the river system. It is suggested that gene flow may be responsible for the poor genetic differentiation amongst populations in the Berg River system. The implication for future management of the system is briefly discussed
Designing and Implementing an Assessment Plan for a Virtual Engineering Lab
This article describes the process of creating, implementing, and assessing an innovative learning tool. The game based laboratory simulation, āGaming for Applied Materials Engineeringā (GAME), incorporated into the Engineering curriculum at a large public university, is intended to facilitate the same learning previously taught in a traditional hands-on laboratory. Through this technological tool, researchers hope to extend an integral learning opportunity to students currently unable to access physical labs, as well as, to augment and reinforce the material taught to those currently enrolled in physical lab courses. Throughout the article, the research team discusses the assessment methodology, describes several challenges overcome, and offers recommendations for others interested in utilizing game-based technology in educational settings. Ā
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