An authentic approach to facilitating transfer of teacher's pedagogical knowledge

The pedagogical knowledge learned by pre-service teachers often fails to transfer to teaching practice. Instead, new teachers revert to instructional strategies they observed as children. This chapter describes design research conducted over four years, where pre-service teachers were immersed in an authentic learning environment using multimedia to learn mathematics assessment strategies. The first study was conducted with pre-service teachers in the second year of their degree, and then the second study followed up with the same people in their second year as practising teachers. The first study revealed several constraints for the participants on professional practice, including limited time and the influence of the supervising teacher. Later, as practising teachers, they faced cultural and practical constraints within the school environment that prevented them from fully operationalising the pedagogical principles they learned as pre-service teachers

Integrating Pile Setup in the LRFD Design of Driven Piles in Louisiana

The purpose of this research study is to evaluate the incorporation of pile setup into driven pile foundation designs in Louisiana. Pile setup is the time-dependent increase in bearing capacity of a driven pile. This phenomenon is widely recognized but is not widely incorporated into foundation designs. Setup primarily occurs in clayey soils which are abundant in Louisiana. After foundation piles are driven, their capacity can significantly increase over a period of time. An empirical formula developed to predict this increase in capacity was evaluated using pile load tests within Louisiana. The setup parameter “A” in the selected formula was back-calculated from the dataset to determine a setup parameter specific to Louisiana soil conditions. Pile capacities including the setup effect were predicted using the calibrated �� value and compared with the measured capacities. Using the results of this comparison, the statistics of the prediction model were obtained, and a reliability analysis using the First Order Reliability Method (FORM) was conducted to calibrate a resistance factor corresponding to the additional capacity due to setup for the strength limit state in a Load and Resistance Factor Design (LRFD) format. This calibrated resistance factor can be used in the design of driven piles to account for the additional increase in capacity that can be expected to occur due to setup. To demonstrate how the additional capacity due to setup will allow driven pile foundation to be more economical, a case study was conducted and concluded the number of required piles can be reduced by about 20% from a design using the pile capacity at 24 hours after driving. In addition, a survey was conducted to gauge the current state of practice and the perception practitioners held regarding setup. The survey was distributed to practitioners in the driven pile industry primarily in Louisiana and the Gulf Coast region

Expansion Potential for Irrigation within the Mississippi Delta Region

17.6 million acres, or 73 percent, of the Mississippi Delta Region is currently cropland and possesses the physical characteristics of slope, texture and soil type which are recommended for irrigation. Economic feasibility of expanding irrigation by flood, furrow and center pivot methods were examined under 24 scenarios representing two sets of crop prices, yield levels, production costs, opportunity costs and six crop rotations. Irrigation was economically feasible for 56 to 100 percent of the cropland across all scenarios. Approximately 88 percent of the cropland can be economically irrigated with flood or furrow in its present form, 8 percent yield highest net returns if furrow irrigated following land forming and 4 percent can be economically irrigated only with center pivot systems

Modeling Supermassive Primordial Stars with MESA

Supermassive stars forming at $z \sim$ 15 - 20 are one of the leading contenders for the origin of the first quasars, over 200 of which have now been discovered at $z >$ 6. These stars likely form in pristine, atomically cooled haloes immersed in strong Lyman-Werner UV backgrounds or in highly supersonic baryon streaming flows. Atomic cooling triggers catastrophic baryon collapse capable of building up stars at rates of up to $\sim$1 M$_{\odot}$ yr$^{-1}$. Here we examine the evolution of supermassive stars with a much larger and finer grid of accretion rates than in previous studies with the \texttt{MESA} stellar evolution code. We find that their final masses range from 3.5 $\times$ 10$^3$ M$_{\odot}$ - 3.7 $\times$ 10$^5$ M$_{\odot}$ at accretion rates of 0.001 M$_{\odot}$ yr$^{-1}$ - 1 M$_{\odot}$ yr$^{-1}$, respectively. We also find that supermassive star evolution diverges at accretion rates of 0.01 M$_{\odot}$ yr$^{-1}$ - 0.02 M$_{\odot}$ yr$^{-1}$, above which they evolve as cool red hypergiants along the Hayashi track and collapse via the general relativistic instability during central hydrogen burning, and below which they evolve as hot blue supergiants and collapse at the end of their nuclear burning lifetimes after exiting the main sequence.Comment: 11 pages, 10 figures, accepted by MNRA

Skilling Up: Providing Educational Opportunities for Aboriginal Education Workers through Technology-based Pedagogy

Over the past decade Aboriginal and Torres Strait Islander studies and perspectives have been mandated across the Australian national curriculum and all teachers are now required to demonstrate strategies for teaching Aboriginal and Torres Strait Islander students and have a broad knowledge of Aboriginal histories, cultures and languages. This paper describes a project focused on enabling Aboriginal Education Workers (AEWs) to play a critical role in transforming these initiatives into real and sustainable change through authentic, technology-based pedagogy. Indigenous research methodologies and design-based research (DBR) were used to investigate the potential educational roles for AEWs enabled by e-learning and new technologies. The project, called Skilling Up: Improving educational opportunities for AEWs through technology based pedagogy was funded by the Office of Learning and Teaching. This paper reports on the findings of the study conducted in Western Australia, including pre-study survey results, together with a description of a unit of study to provide opportunities for AEWs to use technologies in their work, and to create authentic digital stories for use in teacher education. The development of design principles for the design of such environments is also discussed

Skilling Up: Providing Educational Opportunities for Aboriginal Education Workers through Technology-based Pedagogy

Over the past decade Aboriginal and Torres Strait Islander studies and perspectives have been mandated across the Australian national curriculum and all teachers are now required to demonstrate strategies for teaching Aboriginal and Torres Strait Islander students and have a broad knowledge of Aboriginal histories, cultures and languages. This paper describes a project focused on enabling Aboriginal Education Workers (AEWs) to play a critical role in transforming these initiatives into real and sustainable change through authentic, technology-based pedagogy. Indigenous research methodologies and design-based research (DBR) were used to investigate the potential educational roles for AEWs enabled by e-learning and new technologies. The project, called Skilling Up: Improving educational opportunities for AEWs through technology based pedagogy was funded by the Office of Learning and Teaching. This paper reports on the findings of the study conducted in Western Australia, including pre-study survey results, together with a description of a unit of study to provide opportunities for AEWs to use technologies in their work, and to create authentic digital stories for use in teacher education. The development of design principles for the design of such environments is also discussed

Ανάδειξη της αγροτικής παραγωγής στην αστική καθημερινότητα. _προβολή _ εμπόριο _ ενημέρωση στην Θήβα

An 'aggregate economic' value (H), which is a combination of genetic control and relative economic value of traits, for all traits in the breeding objective was developed to aid in multitrait selection of strawberry cultivars in the subtropical southeast Queensland program. A profitability index for 12 traits was calculated from the effect of unit changes in each trait on changes in production costs and profitability. The index was applied to the breeding values of 3008 genotypes to produce estimates of H. H was validated by its high correlation (R=0.77) with year of selection (1945-1998) for commercial cultivars. H values for 3008 genotypes ranged from -0.36 to +0.28, when the zero value was set to the value of the cultivar 'Festival', which is the main cultivar grown in southeast Queensland. Modelling indicated that the gross margins were highly linearly related (R0.98) to H values where the genotype occupied less than 50% of total area planted in the industry, but this relationship became quadratic when the genotype occupied higher percentages of the total area planted to strawberries, and variation in gross margin increased as H values increased. H is efficient in identifying economically superior genotypes, but, when deploying new genotypes with high H, impacts on farm gross margin due to high adoption rates should also be considered

Turbulent Cold Flows Gave Birth to the First Quasars

How quasars powered by supermassive black holes (SMBHs) formed less than a billion years after the Big Bang is still one of the outstanding problems in astrophysics 20 years after their discovery$^{1-4}$. Cosmological simulations suggest that rare cold flows converging on primordial haloes in low-shear environments could have created these quasars if they were 10$^4$ - 10$^5$ M$_{\odot}$ at birth but could not resolve their formation$^{5-8}$. Semianalytical studies of the progenitor halo of a primordial quasar found that it favours the formation of such seeds but could not verify if one actually appeared$^9$. Here we show that a halo at the rare convergence of strong, cold accretion flows creates massive BH seeds without the need for UV backgrounds, supersonic streaming motions, or even atomic cooling. Cold flows drive violent, supersonic turbulence in the halo that prevents star formation until it reaches a mass that triggers sudden, catastrophic baryon collapse that forms 31,000 and 40,000 M$_{\odot}$ stars. This simple, robust process ensures that haloes capable of forming quasars by z $>$ 6 produce massive seeds. The first quasars were thus a natural consequence of structure formation in cold dark matter cosmologies, not exotic, finely-tuned environments as previously thought$^{10-14}$.Comment: Author's version of a Letter published in Nature on July 6th, 202