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981.
Ovidiu Șerban Nicholas Thapen Brendan Maginnis Chris Hankin Virginia Foot 《Information processing & management》2019,56(3):1166-1184
Interest in real-time syndromic surveillance based on social media data has greatly increased in recent years. The ability to detect disease outbreaks earlier than traditional methods would be highly useful for public health officials. This paper describes a software system which is built upon recent developments in machine learning and data processing to achieve this goal. The system is built from reusable modules integrated into data processing pipelines that are easily deployable and configurable. It applies deep learning to the problem of classifying health-related tweets and is able to do so with high accuracy. It has the capability to detect illness outbreaks from Twitter data and then to build up and display information about these outbreaks, including relevant news articles, to provide situational awareness. It also provides nowcasting functionality of current disease levels from previous clinical data combined with Twitter data.The preliminary results are promising, with the system being able to detect outbreaks of influenza-like illness symptoms which could then be confirmed by existing official sources. The Nowcasting module shows that using social media data can improve prediction for multiple diseases over simply using traditional data sources. 相似文献
982.
Xiaolei Wang Ming Tang Jeff Moyen Di Wang Alfred Krner Chris Hawkesworth Xiaoping Xia Hangqiang Xie Carl Anhaeusser Axel Hofmann Junyong Li Linsen Li 《国家科学评论(英文版)》2022,9(3)
The recycling of supracrustal materials, and in particular hydrated rocks, has a profound impact on mantle composition and thus on the formation of continental crust, because water modifies the physical properties of lithological systems and the mechanisms of partial melting and fractional fractionation. On the modern Earth, plate tectonics offers an efficient mechanism for mass transport from the Earth''s surface to its interior, but how far this mechanism dates back in the Earth''s history is still uncertain. Here, we use zircon oxygen (O) isotopes to track recycling of supracrustal materials into the magma sources of early Archean igneous suites from the Kaapvaal Craton, southern Africa. The mean δ18O values of zircon from TTG (tonalite–trondhjemite–granodiorite) rocks abruptly increase at the Paleo-Mesoarchean boundary (ca. 3230 million years ago; Ma), from mantle zircon values of 5‰–6‰ to approaching 7.1‰, and this increase occurs in ≤3230 Ma rocks with elevated Dy/Yb ratios. The 18O enrichment is a unique signature of low-temperature water–rock interaction on the Earth''s surface. Because the later phase was emplaced into the same crustal level as the older one and TTG magmas would derive from melting processes in the garnet stability field (>40 km depth), we suggest that this evident shift in TTG zircon O isotopic compositions records the onset of recycling of the mafic oceanic crust that underwent seawater hydrothermal alteration at low temperature. The onset of the enhanced recycling of supracrustal materials may also have developed elsewhere in other Archean cratons and reflects a significant change in the tectonic realm during craton formation and stabilization, which may be important processes for the operation of plate tectonics on early Earth. 相似文献
983.
Nick Konkol Chris McNamara Joe Sembrat Mark Rabinowitz Ralph Mitchell 《Journal of Cultural Heritage》2009,10(3):362-366
Marble monuments and facades are susceptible to microbial colonization. Microbial growth on a marble surface can develop into unsightly red stains whose removal has proven problematic. The purpose of this study was to determine if the red-brown stains on Isamu Noguchi's marble sculpture Slide Mantra (1991) could be caused by pigment-producing microorganisms and to assess the potential of enzymatic stain remediation. Traditional cell culture methods were used to isolate a pigmented bacterium from a stained area of the sculpture. Sequencing and analysis of the 16S rRNA gene identified the organism as a strain of Serratia marcescens, and FT-IR spectroscopy demonstrated that the pigment produced by the bacteria was most likely a prodigiosin. Decolorization of the pigment in solution demonstrated that the enzyme laccase from the fungus Trametes versicolor has potential as a decolorizing agent. This study suggests that enzymatic decolorization may be applicable to stains on culturally significant marble caused by microbial colonization. 相似文献
984.
985.
This study offers a preliminary exploration of repeat consumption of identical cultural goods, specifically moviegoing. The
term ‘identical’ in this study refers to cases where, for example, individuals view the same film at a movie theater, in a
short time interval, on more than one occasion i.e. experiencing the cultural good in precisely the same format. It is not
meant to embrace the case of individuals who, for example, view a particular film at a movie theater and then see it some
time later in another format, such as via a DVD player. The repeat viewing phenomenon is discussed and then considered empirically.
Films aimed predominantly at children attract the highest number of repeat views, while those aimed at an older audience attract
significantly fewer repeat views. The profile of repeat viewers of the 10 films which attracted the greatest number of repeat
viewers was subject to more detailed scrutiny. In general, repeat viewers tend to be younger but the gender balance differs
markedly according to film content.
An earlier version of this article was presented at the 3rd European Workshop on Applied Cultural Economics, University of
Oviedo in Aviles, Spain 14–16 June 2007 and the 9th International Conference on Arts and Cultural Management (AIMAC), Fundación
Universidad Empresa (ADEIT), Valencia, Spain 8–11 July 2007. We are grateful for comments received and the usual caveat applies. 相似文献
986.
Gamrat Chris Zimmerman Heather Toomey 《Educational technology research and development : ETR & D》2021,69(5):2615-2636
Educational technology research and development - Through design-based research, this study examines a digital badging system to support online, independent teacher Professional development (PD) in... 相似文献
987.
Anne G.M De Bruijn Danny D.N.M. Kostons Irene M.J Van Der Fels Chris Visscher Jaap Oosterlaan Esther Hartman 《Journal of sports sciences》2020,38(15):1806-1817
ABSTRACT This cluster randomized controlled trial (trial-number #) compares effects of two school-based physical activity interventions (aerobic vs. cognitively-engaging) on reading, mathematics, and spelling achievement; and whether effects are influenced by volume of moderate-to-vigorous physical activity and baseline achievement. Twenty-two primary schools participated, where a third and fourth grade class were randomly assigned to the intervention or control group. Intervention groups were randomly assigned to a 14-week aerobic or cognitively-engaging intervention, receiving four physical education lessons a week. Control groups followed their regular physical education program. Academic achievement of 891 children (mean age 9.17 years, 49.4% boys) was assessed with standardized tests before and after the interventions. Post-Test academic achievement did not significantly differ between intervention groups and control group. A higher volume of moderate-to-vigorous physical activity resulted in better post-test mathematics achievement in both intervention groups, and post-test spelling achievement in the cognitively engaging intervention group. Compared to the control group, lower achievers in reading performed better in reading after the cognitively-engaging intervention. A combination of moderate-to-vigorous physical activity and cognitively-engaging exercises seems to have the most beneficial effects. Future intervention studies should take into account quantitative and qualitative aspects of physical activity, and children’s baseline academic achievement. 相似文献
988.
989.
Michelle Durocher Iman Dagher Violeta Ilik Chris Evin Long Jeanette A. Norris Isabel del Carmen Quintana 《Cataloging & classification quarterly》2020,58(3-4):438-448
AbstractThe Program for Cooperative Cataloging (PCC) conducted a multi-institution Pilot project to contribute metadata to the International Standard Name Identifier (ISNI) database. In addition to describing the goals, structure, and activities undertaken in the Pilot, this article examines some of the experiences of PCC metadata practitioners as they sought to incorporate ISNIs into their metadata workflows and pursue a wide range of ISNI use cases. Lastly, the article outlines next steps that flowed from the Pilot as the PCC has parlayed its newly developing identity management expertise into additional PCC program explorations. 相似文献
990.