33 resultados para public understanding of science
em University of Queensland eSpace - Australia
Resumo:
Improving the public understanding of science is an important challenge for the future professional scientists who are our current undergraduates. In this paper, we present a conceptual model that explores the role of mass media as community gatekeepers of new scientific findings. This model frames the benefits for undergraduate science students to learn about media genres so that they can learn to communicate science more effectively to nonprofessional audiences. Informed by this Media Role model, we then detail a novel writing task for undergraduate physiology students, the Opinion Editorial (Op-Ed), and an accompanying Peer Review. The Op-Ed genre was directly taught to the students by a professional journalist. As an assessment task, students presented a recent, highly technical paper as an Op-Ed. This was assessed by both faculty members and peers using a detailed assessment rubric. Most students were able to replicate the features of Op-Eds and attained high grades on their writing tasks. Survey data from final-year physiology students (n = 230) were collected before and after the implementation of the Op-Ed/Peer Review. These indicated that most students were aware of the importance of scientists to effectively communicate their knowledge to nonprofessional audiences, that the Op-Ed writing task was challenging, and that they believed that their ability to write to nonprofessional audiences was improved after explicit teaching and feedback.
Resumo:
Background: For research on physical activity interventions to progress systematically, the mechanisms of action must be studied. In doing so, the research methods and their associated concepts and terminology become more complex. It is particularly important to clearly distinguish among determinants, correlates, mediators, moderators, and confounder variables used in physical activity research. This article examines the factors that are correlated with and that may have a causal relationship to physical activity. Methods and Results: We propose that the term correlate be used, instead of determinant, to describe statistical associations or correlations between measured variables and physical activity. Studies of the correlates of physical activity are reviewed. The findings of these studies can help to critique existing theories of health behavior change and can provide hypotheses to be tested in intervention studies from which it is possible to draw causal inferences. Mediator, moderator, and confounder variables can act to influence measured changes in physical activity. Intervening causal variables that are necessary to complete a cause-effect pathway between an intervention and physical activity are termed mediators. The relationship between an intervention and physical activity behaviors may vary for different groups; the strata by which they vary are levels of moderators of the relationship. Other factors may distort or affect the observed relationships between program exposure and physical activity, and are known as confounders. Conclusions: Consistent use of terms and additional research on mediators and moderators of intervention effects will improve our ability to understand and influence physical activity.
Resumo:
Vertical direct chill (VDC) casting of aluminium alloys is a mature process that has evolved over many decades through gradual change to both equipment design and casting practice. Today, air-pressurised, continuous lubrication, hot top mould systems with advanced station automation are selected as the process of choice for producing extrusion billet. Specific sets of operating parameters are employed on these stations for each alloy and size combination to produce optimal billet quality. The designs and parameters are largely derived from past experience and accumulated know-how. Recent experimental work at the University of Queensland has concentrated on understanding the way in which the surface properties of liquid aluminium alloys, e.g., surface tension, wetting angle and oxide skin strength, influence the size and shape of the naturally-stab le meniscus for a given alloy, temperature and atmosphere. The wide range of alloy-and condition-dependent values measured has led to the consideration of how these properties impact the stability of the enforced molten metal meniscus within the hot top mould cavity. The actual shape and position of the enforced meniscus is controlled by parameters such as the upstream conduction distance (UCD) from sub-mould cooling and the molten metal head. The degree of deviation of this actual meniscus from the predicted stable meniscus is considered to be a key driver in surface defect formation. This paper reports on liquid alloy property results and proposes how this knowledge might be used to better design VDC mould systems and casting practices.
Resumo:
Managing hawksbill turtle populations for use and conservation requires (i) adequate scientific understanding of their population status and dynamics and (ii) consideration of the public’s attitudes to this species. This study employs experimental surveys to assess the Australian public’s attitudes towards the hawksbill turtle, their knowledge of it, their views about its sustainable commercial harvesting, and their support and financial contribution for the species’ conservation. Contingent valuation reveals that the Australian public’s willingness to contribute to the conservation of the hawksbill turtle is high even in comparison to threatened Australian bird and mammal fauna. Most of this stated contribution is based on the intrinsic (non-use) value associated with the hawksbill turtle. It seems that the Australian public will only accept its harvesting if the sustainability of this is assured and its population is more secure. The CITES categorisation of the hawksbill as an Appendix I species hampers the development of techniques for its sustainable use.
Resumo:
Organic petrology supported by electron microscopical and micro-analytical techniques was applied to organic matter in Proterozoic sediments to better understand hydrothermal processes responsible for ore-grade mineralisation. It was shown that organic maturation was not only closely linked to the geological history of the sediments, but also highlighted heat transfer by convection as differentiated from conduction solely through sediment burial and step-wise subsidence. Water-rock ratios effect organic maturation in hydrothermal systems, and erratic reflectance profiles are indicators of convective heat transfer. Identification and characterisation of organic materials in terms of source rock and migrated hydrocarbons was shown to be a powerful tool in reconstructing the thermal history of sediments, identifying hydrothermal episodes, fluid pathways and heat source in the northern Australian Proterozoic basins. Higher reflectance of organic matter towards the central parts of the Mount Isa Basin and some of the most northerly parts point to proximity to higher heat flow at times, in contrast to relatively low temperatures prevailing in the western parts of the basin, next to the Murphy Inlier. A close correlation shown between peak organic reflectance values and super-sequence boundaries farther highlighted the valuable information to be gained from organic petrology, by allowing the separation of processes responsible for metal dissolution and transportation from those inducing precipitation. (C) 2001 Elsevier Science B.V All rights reserved.
Resumo:
The South African style SAG (RoM) mills operate in a window that is almost exclusive from the operation of the Australian and North American mills that have been used for the development of SAG mill models. Combining good quality, test data from the RoM mills is extending and improving these models, and assisting in a practical manner in improving our understanding of SAG/AG milling. Data from high mill loads, both in absolute filling and ball loading, have been used to extend and improve the JK SAG mill model. This improved understanding has been successfully applied to increasing the throughput of a mill by 8%. Data is presented on relationships between power and load for high mill loading. Slurry pooling is common in closed-circuit RoM mills, and the detrimental effect of this has been dramatically demonstrated at ALCOA with a mill throughput increase of over 20%. Techniques for calculating the effects of slurry pooling have been developed and a new pulp lifter system designed to give optimal slurry discharge. The influence of mill speed in shifting the product size distribution has also been measured. (C) 2001 Elsevier Science Ltd. All rights reserved.
Resumo:
The four-link chain of the motor unit represents the contemporary end-point of some two millennia of evolving knowledge in neuroscience. The paradigm shift in neuromuscular epistemology occurred in the mid-17th century. In 1666, the newly graduated Dutch doctor, Jan Swammerdam (1637-1680) published his former investigations of dissected nerve-muscle preparations. These experiments comprised the quantum leap from observation and speculation, to that of experimentation in the field of neuroanatomy and neurophysiology. In what he termed 'A Curious Experiment' he also described the phenomenon of intrinsic muscle excitability - I cannot observe that the muscle in the living animal ever absolutely ceases from all motion. Eighty years later (1752), von Haller demonstrated experimentally that irritability (contractility) was an intrinsic property of all muscular tissue; and distinguished between the sensibility of nerve impulses and the irritability of muscular contraction. This experimental progression from Swammerdam to von Haller culminated in 1850, when Claude Bernard's studies in experimental pharmacology confirmed that muscle was a functional unit, independent of any electrical innervation via its supplying nerve. This account comprises an audit of Swammerdam's work in the perspective of neuromuscular knowledge. (C) 2002 Elsevier Science B.V. All rights reserved.
Resumo:
Children aged between 3 and 7 years were taught simple and dimension-abstracted oddity discrimination using learning-set training techniques, in which isomorphic problems with varying content were presented with verbal explanation and feedback. Following the training phase, simple oddity (SO), dimension-abstracted oddity with one or two irrelevant dimensions, and non-oddity (NO) tasks were presented (without feedback) to determine the basis of solution. Although dimension-abstracted oddity requires discrimination based on a stimulus that is different from the others, which are all the same as each other on the relevant dimension, this was not the major strategy. The data were more consistent with use of a simple oddity strategy by 3- to 4-year-olds, and a most different strategy by 6- to 7-year-olds. These strategies are interpreted as reducing task complexity. (C) 2002 Elsevier Science Inc. All rights reserved.
Resumo:
During the period 1778-1780 the Swiss physician Samuel A A D Tissot (1728-1797) published his Traite des nerfs et de leur maladies, a work which continued to be available and widely influential until at least the middle of the following century. It contained a long chapter dealing with migraine, based on the earlier literature on the topic and on Tissot's own clinical experience. The work appeared at the beginning of the modern era of interest in migraine, and provided the first reasonably adequate and systematic account of the disorder to become widely available. Its descriptions of migraine phenomena have an enduring validity, though Tissot's ideas on the pathogenesis of the disorder, viz. that it usually arose from stomach disturbance, were not founded on satisfactory evidence and are long since superseded. (C) 2003 Elsevier Science Ltd. All rights reserved.
Resumo:
Litchi (Litchi chinensis Sonn.) is a subtropical to tropical fruit of high commercial value in international trade. However, harvested litchi fruit rapidly lose their bright red skin colour. Peel browning of harvested litchi fruit has largely been attributed to rapid degradation of red anthocyanin pigments. This process is associated with enzymatic oxidation of phenolics by polyphenol oxidase (PPO) and/or peroxidase (POD). PRO and POD from litchi pericarp cannot directly oxidize anthocyanins. Moreover, PPO substrates in the pericarp are not well characterised. Consequently, the roles of PPO and POD in litchi browning require further investigation. Recently, an anthocyanase catalysing the hydrolysis of sugar moieties from anthocyanin to anthocyanidin has been identified in litchi peel for the first time. Thus, litchi enzymatic browning may involve an anthocyanase-anthocyanin-phenolic-PPO reaction. Current research focus is on characterising the properties of the anthocyanase involved in anthocyanin degradation. Associated emphasis is on maintenance of membrane functions in relation to loss of compartmentation between litchi peel oxidase enzymes and their substrates. (C) 2004 Elsevier Ltd. All rights reserved.
Resumo:
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