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

The indigenous knowledge debate in life sciences: what about Indian indigenous knowledge?

Institute for Science and Technology Education (ISTE

Why do SGLT2 inhibitors reduce heart failure hospitalization? A differential volume regulation hypothesis

The effect of a sodium glucose cotransporter 2 inhibitor (SGLT2i) in reducing heart failure hospitalization in the EMPA-REG OUTCOMES trial has raised the possibility of using these agents to treat established heart failure. We hypothesize that osmotic diuresis induced by SGLT2 inhibition, a distinctly different diuretic mechanism than other diuretic classes, results in greater electrolyte-free water clearance, and ultimately in greater fluid clearance from the interstitial fluid (IF) space than from the circulation, potentially resulting in congestion relief with minimal impact on blood volume, arterial filling, and organ perfusion. We utilize a mathematical model to illustrate that electrolyte-free water clearance results in a greater reduction in IF volume compared to blood volume, and that this difference may be mediated by peripheral sequestration of osmotically inactive sodium. By coupling the model with data on plasma and urinary sodium and water in healthy subjects administered either the SGLT2i dapagliflozin or loop diuretic bumetanide, we predict that dapagliflozin produces a 2-fold greater reduction in IF volume compared to blood volume, while the reduction in IF volume with bumetanide is only 78% of the reduction in blood volume. Heart failure is characterized by excess fluid accumulation, in both the vascular compartment and interstitial space, yet many heart failure patients have arterial underfilling due to low cardiac output, which may be aggravated by conventional diuretic treatment. Thus, we hypothesize that by reducing IF volume to a greater extent than blood volume, SGLT2 inhibitors might provide better control of congestion without reducing arterial filling and perfusion

Carrot and stick?: Impact of a low-stakes school accountability program on student achievement

A key concern in the design of education policies relates to the structure of incentives in accountability systems. This paper examines a school accountability program that provides financial support to low-performing schools but has no direct punishment scheme for recipients who do not exhibit improvement. Although the program does not include high-stakes consequences, our estimates indicate that the program reduced the share of underperforming students by 18 percent. This paper's results suggest that to improve student achievement, a school accountability program does not need to set high-stakes consequences that potentially induce unwanted strategic behaviors on the part of school workers

A new VLA/e-MERLIN limit on central images in the gravitational lens system CLASS B1030+074

We present new VLA 22-GHz and e-MERLIN 5-GHz observations of CLASS B1030+074, a two-image strong gravitational lens system whose background source is a compact flat-spectrum radio quasar. In such systems we expect a third image of the background source to form close to the centre of the lensing galaxy. The existence and brightness of such images is important for investigation of the central mass distributions of lensing galaxies, but only one secure detection has been made so far in a galaxy-scale lens system. The noise levels achieved in our new B1030+074 images reach 3 microJy/beam and represent an improvement in central image constraints of nearly an order of magnitude over previous work, with correspondingly better resulting limits on the shape of the central mass profile of the lensing galaxy. Simple models with an isothermal outer power law slope now require either the influence of a central supermassive black hole, or an inner power law slope very close to isothermal, in order to suppress the central image below our detection limit. Using the central mass profiles inferred from light distributions in Virgo galaxies, moved to z=0.5, and matching to the observed Einstein radius, we now find that 45% of such mass profiles should give observable central images, 10% should give central images with a flux density still below our limit, and the remaining systems have extreme demagnification produced by the central SMBH. Further observations of similar objects will therefore allow proper statistical constraints to be placed on the central properties of elliptical galaxies at high redshift.Comment: Accepted by Monthly Notices of the Royal Astronomical Society. 16 pages, 8 figure

Using DNA Information to Breed for Disease-resistant Strawberries

Strawberries are susceptible to many diseases that cause damage to leaves and fruit, such as powdery mildew. Many chemical sprays are used to control disease, but there is an industry, environmental and societal push to move away from fungicides. Breeding for disease-resistant varieties offers an alternative approach, and DNA information can be used in this strategy. We identified multiple genetic markers linked with resistance to powdery mildew in leaves and fruit using a statistical modelling method called ‘genome-wide association studies’. We also used DNA information across the entire genome to predict the susceptibility of different strawberry varieties. These results will help Queensland strawberry breeders to identify candidate varieties that are resistant to powdery mildew without expensive and time-consuming disease screening trials. These statistical methods can also be applied to other diseases, as well as yield and fruit quality traits