3,485 research outputs found
The indigenous knowledge debate in life sciences: what about Indian indigenous knowledge?
Institute for Science and Technology Education (ISTE
The conundrum of integrating indigenous knowledge in science curriculum themes: a review of different viewpoints
The leitmotiv of this paper is the relationship between the natural sciences and indigenous knowledge, and whether indigenous knowledge has a place in the school science curriculum. In this review paper, various perspectives on the role of indigenous knowledge in the science classroom are explored. Based on the tenets of respective science and indigenous knowledge, three different perspectives on such epistemological border-crossing are explored: the inclusive, the exclusive, and the ‘overlapping domains’ perspectives. The authors also consider factors that influence such border-crossing, such as teacher and learner factorsInstitute for Science and Technology Education (ISTE
Measuring the dynamical length of galactic bars
We define a physically-motivated measure for galactic bar length, called the
dynamical length. The dynamical length of the bar corresponds to the radial
extent of the orbits that are the backbone supporting the bar feature. We
propose a direct observational technique using integral field unit spectroscopy
to measure it. Identifying these orbits and using the dynamical length is a
more faithful tracer of the secular evolution and influence of the bar. We
demonstrate the success of the metric for recovering the maximal bar-parenting
orbit in a range of simulations, and to show its promise we perform its
measurement on a real galaxy. We also study the difference between
traditionally used ellipse fit approaches to determine bar length and the
dynamical length proposed here in a wide range of bar-forming N-body
simulations of a stellar disc and dark matter halo. We find that ellipse
fitting may severely overestimate measurements of the bar length by a factor of
1.5-2.5 relative to the extent of the orbits that are trapped and actually
comprise the bar. This bias leads to overestimates of both bar mass and the
ratio of corotation radius to bar length, i.e. the bar speed, affecting
inferences about the evolution of bars in the real universe.Comment: Submitted to MNRAS, comments welcome. arXiv admin note: text overlap
with arXiv:1903.0820
Effects of an Advocacy Trial on Food Industry Salt Reduction Efforts—An Interim Process Evaluation
The decisions made by food companies are a potent factor shaping the nutritional quality of the food supply. A number of non-governmental organizations (NGOs) advocate for corporate action to reduce salt levels in foods, but few data define the effectiveness of advocacy. This present report describes the process evaluation of an advocacy intervention delivered by one Australian NGO directly to food companies to reduce the salt content of processed foods. Food companies were randomly assigned to intervention (n = 22) or control (n = 23) groups. Intervention group companies were exposed to pre-planned and opportunistic communications, and control companies to background activities. Seven pre-defined interim outcome measures provided an indication of the effect of the intervention and were assessed using intention-to-treat analysis. These were supplemented by qualitative data from nine semi-structured interviews. The mean number of public communications supporting healthy food made by intervention companies was 1.5 versus 1.8 for control companies (p = 0.63). Other outcomes, including the mean number of news articles, comments and reports (1.2 vs. 1.4; p = 0.72), a published nutrition policy (23% vs. 44%; p = 0.21), public commitment to the Australian government’s Food and Health Dialogue (FHD) (41% vs. 61%; p = 0.24), evidence of a salt reduction plan (23% vs. 30%; p = 0.56), and mean number of communications with the NGO (15 vs. 11; p = 0.28) were also not significantly different. Qualitative data indicated the advocacy trial had little effect. The absence of detectable effects of the advocacy intervention on the interim markers indicates there may be no impact of the NGO advocacy trial on the primary outcome of salt reduction in processed foods
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