12,356 research outputs found
What is the object of the encapsulation of a process?
Several theories have been proposed to describe the transition from process to object in mathematical thinking. Yet, what is the nature of this ''object'' produced by the ''encapsulation'' of a process? Here, we outline the development of some of the theories (including Piaget, Dienes, Davis, Greeno, Dubinsky, Sfard, Gray, and Tall) and consider the nature of the mental objects (apparently) produced through encapsulation and their role in the wider development of mathematical thinking. Does the same developmental route occur in geometry as in arithmetic and algebra? Is the same development used in axiomatic mathematics? What is the role played by imagery
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Sugar intake among German adolescents: trends from 1990-2016 based on biomarker excretion in 24-h urine samples
Trend analyses based on dietary records suggest decreases in the intakes of total (TS), added (AS) and free sugar (FS) since 2005 among children and adolescents in Germany. In terms of age trends, TS intake decreased with increasing age. However, self-reported sugar intake in epidemiological studies is criticized, as it may be prone to bias due to selective underreporting. Furthermore, adolescents are more susceptible to underreporting than children. We thus analyzed time and age trends in urinary fructose excretion (FE), sucrose excretion (SE) and the sum of both (FE+SE) as biomarkers for sugar intake among 8.5-16.5-year-old adolescents. Urinary sugar excretion was measured by UPLC-MS/MS in 997 24-h urine samples collected from 239 boys and 253 girls participating in the DONALD study cohort between 1990 and 2016. Time and age trends of log-transformed FE, SE and FE+SE were analyzed using polynomial mixed-effects regression models. Between 1990 and 2016 FE as well as FE+SE decreased (linear time trend: p=0.0272 and p<0.0001, respectively). A minor increase in excretion during adolescence was confined to FE (linear age trend: p=0.0017). The present 24-h excretion measurements support a previously reported dietary-record based decline in sugar intake since 2005. However, the previous seen dietary record-based decrease in TS from childhood to late adolescence was not confirmed by our biomarker analysis, suggesting a constant sugar intake for the period of adolescence
Spectroscopic and redox properties of amine-unctionalized K_2[Os-^(II)(bpy)(CN)_4] complexes
We report the first examples of amine-functionalized K_2[Os^(II)(bpy)(CN)_4] (bpy = 2,2'-bipyridine) complexes. The tetracyanoosmate complexes were prepared by UV irradiation (λ = 254 nm) of K_4[Os^(II)(CN)_6] and primary amine-functionalized bpy ligands in acidic aqueous media. The aqueous solution pH dependences of the spectroscopic and redox properties of 4,4'- and 5,5'-substituted complexes have been investigated. The pendant amine functional groups and coordinated cyanide ligands are basic sites that can be sequentially protonated, thereby allowing systematic tuning of electrochemical and optical spectroscopic properties
Cultural safety training for allied health students in Australia
Culturally safe health practitioners are essential for effective service provision to culturally diverse populations, including Indigenous Australians. Therefore, cultural safety education during training as a health care professional is an essential component in helping improve the health of Indigenous Australians. This study examined whether the implementation of an Indigenous cultural safety education workshop increased self-rated cultural safety knowledge and attitudes of allied health students. The study employed a quantitative before-and-after design using pre- and post-surveys to determine the level of attitudinal change in students who attended a day long workshop. The study sample consisted of 1st year (n = 347) and 4th year (n = 149) allied health students at a regional Australian university over the years 2007-2011. Whilst the results of this current study are varied in terms of achieving positive change across all of the taught items of knowledge and attitude, they provide some evidence around the value of this type of curriculum intervention in helping develop culturally safe practitioners. An important finding was around the student's becoming self-aware about their own values and cultural identity, combined with acknowledging the importance of this cultural identity to interactions with clients. This form of 'cultural humility' appears to be an important step to becoming a culturally safe practitioner. These types of interventions would be enhanced through embedding and scaffolding throughout the curricula
Rocks Associated with the Mississippian-Pennsylvanian Unconformity in Southwestern Indiana
Indiana Geological Survey Guidebook 9The purpose of this field conference is to acquaint participants with strata that are associated with the Mississippian-Pennsylvanian boundary in southwestern Indiana. Criteria which aid in distinguishing between Mansfield strata of Pottsville (early Pennsylvanian) age and clastic formations of Chester (late Mississippian) age will receive considerable attention in discussions at evening meetings and on the outcrop. Inspection of limestone and sandstone quarries will afford an insight into the economic products of Chester and Mansfield rocks. Participants may collect fossils at many of the stops.Indiana Geological Survey; Indiana Department of Conservation
Department of Geology, Indiana Universit
Cyclometalated Iridium(III) Complexes with Deoxyribose Substituents
Fundamental study of enzymatic nucleoside transport suffers for lack of optical probes that can be tracked noninvasively. Nucleoside transporters are integral membrane glycoproteins that mediate the salvage of nucleosides and their passage across cell membranes. The substrate recognition site is the deoxyribose sugar, often with little distinction among nucleobases. Reported here are nucleoside analogues in which emissive, cyclometalated iridium(III) complexes are “clicked” to C-1 of deoxyribose in place of canonical nucleobases. The resulting complexes show visible luminescence at room temperature and 77 K with microsecond-length triplet lifetimes. A representative complex is crystallographically characterized. Transport and luminescence are demonstrated in cultured human carcinoma (KB3-1) cells
Cyclometalated Iridium(III) Complexes with Deoxyribose Substituents
Fundamental study of enzymatic nucleoside transport suffers for lack of optical probes that can be tracked noninvasively. Nucleoside transporters are integral membrane glycoproteins that mediate the salvage of nucleosides and their passage across cell membranes. The substrate recognition site is the deoxyribose sugar, often with little distinction among nucleobases. Reported here are nucleoside analogues in which emissive, cyclometalated iridium(III) complexes are “clicked” to C-1 of deoxyribose in place of canonical nucleobases. The resulting complexes show visible luminescence at room temperature and 77 K with microsecond-length triplet lifetimes. A representative complex is crystallographically characterized. Transport and luminescence are demonstrated in cultured human carcinoma (KB3-1) cells
IVOA Recommendation: Vocabularies in the Virtual Observatory Version 1.19
This document specifies a standard format for vocabularies based on the W3C's
Resource Description Framework (RDF) and Simple Knowledge Organization System
(SKOS). By adopting a standard and simple format, the IVOA will permit
different groups to create and maintain their own specialised vocabularies
while letting the rest of the astronomical community access, use, and combine
them. The use of current, open standards ensures that VO applications will be
able to tap into resources of the growing semantic web. The document provides
several examples of useful astronomical vocabularies
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Faculty authors explore Spanish vanguard poetry, fatherhood, multi-modal learning, and more
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