971 resultados para ONE-COMPONENT


Relevância:

60.00% 60.00%

Publicador:

Resumo:

One component of biosecurity is protection against invasive alien species, which are one of the most important threats worldwide to native biodiversity and economic profitability in various sectors, including agriculture. However, agricultural producers are not homogeneous. They may have different objectives and priorities, use different technologies, and occupy heterogeneous parcels of land. If the producers differ in terms of their attitude towards invasive pests and the damages they cause, there are probably external effects in the form of pest spread impacts and subsequent damages caused. We study such impacts in the case of two producer types: profit-seeking professional producers and utility-seeking hobby producers. We show that the hobby producer, having first set a breeding ground for the pest, under-invests in pest control. We also discuss potential policy instruments to correct this market failure and highlight the importance of considering different stakeholders and their heterogeneous incentives when designing policies to control invasive alien species.

Relevância:

60.00% 60.00%

Publicador:

Resumo:

By eliminating the short range negative divergence of the Debye–Hückel pair distribution function, but retaining the exponential charge screening known to operate at large interparticle separation, the thermodynamic properties of one-component plasmas of point ions or charged hard spheres can be well represented even in the strong coupling regime. Predicted electrostatic free energies agree within 5% of simulation data for typical Coulomb interactions up to a factor of 10 times the average kinetic energy. Here, this idea is extended to the general case of a uniform ionic mixture, comprising an arbitrary number of components, embedded in a rigid neutralizing background. The new theory is implemented in two ways: (i) by an unambiguous iterative algorithm that requires numerical methods and breaks the symmetry of cross correlation functions; and (ii) by invoking generalized matrix inverses that maintain symmetry and yield completely analytic solutions, but which are not uniquely determined. The extreme computational simplicity of the theory is attractive when considering applications to complex inhomogeneous fluids of charged particles.

Relevância:

60.00% 60.00%

Publicador:

Resumo:

Climate simulations by 16 atmospheric general circulation models (AGCMs) are compared on an aqua-planet, a water-covered Earth with prescribed sea surface temperature varying only in latitude. The idealised configuration is designed to expose differences in the circulation simulated by different models. Basic features of the aqua-planet climate are characterised by comparison with Earth. The models display a wide range of behaviour. The balanced component of the tropospheric mean flow, and mid-latitude eddy covariances subject to budget constraints, vary relatively little among the models. In contrast, differences in damping in the dynamical core strongly influence transient eddy amplitudes. Historical uncertainty in modelled lower stratospheric temperatures persists in APE. Aspects of the circulation generated more directly by interactions between the resolved fluid dynamics and parameterized moist processes vary greatly. The tropical Hadley circulation forms either a single or double inter-tropical convergence zone (ITCZ) at the equator, with large variations in mean precipitation. The equatorial wave spectrum shows a wide range of precipitation intensity and propagation characteristics. Kelvin mode-like eastward propagation with remarkably constant phase speed dominates in most models. Westward propagation, less dispersive than the equatorial Rossby modes, dominates in a few models or occurs within an eastward propagating envelope in others. The mean structure of the ITCZ is related to precipitation variability, consistent with previous studies. The aqua-planet global energy balance is unknown but the models produce a surprisingly large range of top of atmosphere global net flux, dominated by differences in shortwave reflection by clouds. A number of newly developed models, not optimised for Earth climate, contribute to this. Possible reasons for differences in the optimised models are discussed. The aqua-planet configuration is intended as one component of an experimental hierarchy used to evaluate AGCMs. This comparison does suggest that the range of model behaviour could be better understood and reduced in conjunction with Earth climate simulations. Controlled experimentation is required to explore individual model behaviour and investigate convergence of the aqua-planet climate with increasing resolution.

Relevância:

60.00% 60.00%

Publicador:

Resumo:

Research in ruminant nutrition and helminth control with forages, which contain condensed tannins (CT), suggests that varying responses may depend not only on CT concentration but also on CT composition. An experiment was designed to test this by feeding 2 dried sainfoin cultivars (Visnovsky and Perly), which differed in CT properties, to lambs that were artificially infected with the abomasal blood-sucking nematode Haemonchus contortus. Twenty-four infected lambs received one of these 2 cultivars; the feeds were either untreated or treated with the CT-binding polyethylene glycol over 4 wk (n = 6). The 2 cultivars were also fed to 2 × 6 uninfected lambs. Nutrient digestibility, N balance, ADG, plasma urea together with indicators of infection [fecal egg count (FEC), abomasal worm count, per capita female fecundity, erythrocytic indices, and serum protein] were determined. The specific effects of sainfoin cultivar, CT, and infection were evaluated by contrast analysis. Digestibility of both NDF and ADF were lower (P < 0.001) with Perly compared to Visnovsky. The apparent nutrient digestibility was reduced (P < 0.001) by CT. However, no clear cultivar effects were evident on N excretion and retention. Condensed tannins reduced (P = 0.05) body N retention and shifted (P < 0.001) N excretion from urine to feces. Unlike cultivar and CT, infection decreased (P = 0.002) ADG. Plasma urea concentration was lower (P = 0.007) in Perly- compared to Visnovsky-fed lambs and was decreased (P < 0.001) by CT. Plasma concentrations of essential and semi-essential AA were increased (P < 0.001) by CT. The groups of infected lambs did not clearly differ in abomasal worm counts and erythrocytic indicators. In the last 2 to 3 wk of the experiment, FEC was lower (P ≤ 0.01) when feeding CT. The lack of substantial cultivar effects suggests that the differences in CT properties may have been too small to result in nutritional and anthelmintic effects. The present results indicate that sainfoin CT had a mitigating effect on FEC and, consequently, pasture infectivity. However, the reduction was too low to expect any significant benefits in an Haemonchus-dominated system. Therefore, the use of sainfoin for controlling H. contortus should only be one component within an integrated worm control system.

Relevância:

60.00% 60.00%

Publicador:

Resumo:

The purpose of this paper is to report on the facilities available, organisation of, and staff attitudes to early years outdoor education from schools within the south east of England, focusing on provision for children aged three to five. One component of the successful education of the child involves providing an ‘environment for learning’, including the facilities, layout and routines. This paper presents findings concerning the type and variety of facilities available outside; the various styles of organisation of the space; staff attitudes about: their roles, their aims for the environment, children’s behaviour and learning, and perceived drawbacks to practice. This paper draws on empirical data collected from schools within the University of Reading partnership. The findings suggest that although all early years settings must adhere to the statutory framework there are a range of facilities available, and there are a number of ways this environment is organised. Further there appears to be uncertainty about the adult role outside and the aims for activities. The conclusions drawn indicate that staff do not appear to be linking their aims for outdoor education to the facilities provided or to their actions outside. This means there is not a clear link between what staff provide outside and the declared ambitions for learning. This study is important as all educators need to be certain about their aims for education to ensure best outcomes for children. The implications of these findings for early years teachers are that they need to be able to articulate their aims for outdoor education and to provide the correct facilities to achieve these aims. Finally this study was undertaken to raise debate, posit questions and to ascertain the parameters for further research about the early years outdoor environment.

Relevância:

60.00% 60.00%

Publicador:

Resumo:

Electronically complementary, low molecular weight polymers that self-assemble through tuneable π-π stacking interactions to form extended supramolecular polymer networks have been developed for inkjet printing applications and successfully deposited using three different printing techniques. Sequential overprinting of the complementary components results in supramolecular network formation through complexation of π-electron rich pyrenyl or perylenyl chain-ends in one component with π-electron deficient naphthalene diimide residues in a chain-folding polyimide. The complementary π-π stacked polymer blends generate strongly coloured materials as a result of charge-transfer absorptions in the visible spectrum, potentially negating the need for pigments or dyes in the ink formulation. Indeed, the final colour of the deposited material can be tailored by changing varying the end-groups of the π electron rich polymer component. Piezoelectric printing techniques were employed in a proof of concept study to allow characterisation of the materials deposited, and a thermal inkjet printer adapted with imaging software enabled a detailed analysis of the ink-drops as they formed, and of their physical properties. Finally, continuous inkjet printing allowed greater volumes of material to be deposited, on a variety of different substrate surfaces, and demonstrated the utility and versatility of this novel type of ink for industrial applications.

Relevância:

60.00% 60.00%

Publicador:

Resumo:

Sociology, hybrids and social reality: the case of nuclear waste The continuing technological transformation of nature means that sociology’s traditional vision of a sharp divide between nature and society is becoming ever harder to defend. Starting from Bruno Latour’s critique of modernity, and Nikolas Rose’s explorations of political power beyond the state, this article presents a framework for analysing the expanding wealth of hybrids of nature and society surrounding us today, and the problems of government they pose. These hybrids confront us with the need to rethink sociology’s conception of ‘the social’. With Latour’s help, the interplay of nature and society can be understood as subject to technical mediation, opening the way for studies of the varying arrangements through which different configurations of nature and society are produced. Rather than alternative social constructions of nature, what sociologists should be at pains to analyse and question are different programmes and strategies for bringing together natural and social forces in durable combinations. In the article, the geological disposal of nuclear waste serves as a useful example for exploring the fruitfulness of the analytical framework put forward. This complex undertaking constitutes just one component in a larger field of technoscientific endeavour that has irrevocably transformed nature while simultaneously re-making society. Addressing this case, we seek to reveal the promise of a sociology that does not bound ‘the social’ in advance, but rather makes the co-production of technology and society one of its most important objects of study.

Relevância:

60.00% 60.00%

Publicador:

Resumo:

Descriptive measurement reliability and validity data are reported on scores from the Mathematics Self-Efficacy Scale (MSES) in two contexts—class and test—for a sample of 302 Australian high school students. Summated scores on the MSES correlated r = .74, and together these items yielded one component that explained 49% of the variance. MSES scores demonstrated internal reliability for both class and test (Cronbach alphas = .86 and .90). Statistically significant correlations between MSES scores, past mathematics grades, and Marsh’s Self-Description Questionnaire III (Math) were used to indicate the convergent validity of scores for the MSES. Discriminant validity of the MSES scores was suggested by the lack of significant correlations between the MSES measures and students’ desired English grades. Statistically significant correlations between MSES scores and students’ desired mathematics grades indicated concurrent validity of the MSES measures. A statistically significant difference between class and test scores supported Bandura’s prescription for context specificity in efficacy research.

Relevância:

60.00% 60.00%

Publicador:

Resumo:

Education provides unique opportunities for individuals to develop their full character as Australian citizens who can play a part in the shaping of the future. All educational settings have an important role to play in bridging differences and promoting mutual respect, tolerance and understanding between people of different races, cultures, and religions. The curriculum is one component of the wider educational milieu that should be 'an enabling mechanism that nurtures adjustment to change, and simultaneously provides a roadmap of expectation' (Bruniges, 2005, p.15). As the rate and diversity of both local and global change accelerates, education continues to be faced with a multiplicity of challenges. The ways in which we respond to this will influence both the society and the curriculum that we design, implement and evaluate. Currently music educators implementing the Victorian Essential Learning Standards (VELS) are faced with the challenge of developing multicultural practices that align with both curriculum initiatives and create authentic experiences for students. As in the well-known story of the blind men and the elephant, teachers are faced with resources that offer only a shallow introduction to what is a multifaceted field. The question we pose is: 'How do educators embrace a vast range of cultural and social dimensions in our school music programmes without being like a blind man, grasping only one perspective of an extensive and complex whole?'

Relevância:

60.00% 60.00%

Publicador:

Resumo:

There are many proposals for managing biodiversity by using surrogates, such as umbrella, indicator, focal, and flagship species. We use the term biodiversity management unit for any ecosystem-based classificatory scheme for managing biodiversity. The sufficiency of biodiversity management unit classification schemes depends upon (1) whether different biotic elements (e.g., trees, birds, reptiles) distinguish between biodiversity management units within a classification (i.e., coherence within classes}; and (2) whether different biotic elements agree upon similarities and dissimilarities among biodiversity management unit classes (i.e., conformance among classes). Recent evaluations suggest that biodiversity surrogates based on few or single taxa are not useful. Ecological vegetation classes are an ecosystem-based classification scheme used as one component for biodiversity management in Victoria, Australia. Here we evaluated the potential for ecological vegetation classes to be used as biodiversity management units in the box-ironbark ecosystem of central Victoria, Australia. Eighty sites distributed among 14 ecological vegetation classes were surveyed in the same ways for tree species, birds, mammals, reptiles, terrestrial invertebrates, and nocturnal flying insects. Habitat structure and geographic separations also were measured, which, with the biotic elements, are collectively referred to as variables. Less than half of the biotic element-ecological vegetation class pairings were coherent. Generalized Mantel tests were used to examine conformance among variables with respect to ecological vegetation classes. While most tests were not significant, birds, mammals, tree species, and habitat structure together showed significant agreement on the rating of similarities among ecological vegetation classes. In this system, use of ecological vegetation classes as biodiversity management units may account reasonably well for birds, mammals, and trees; but reptiles and invertebrates would not be accommodated. We conclude that surrogates will usually have to be augmented or developed as hierarchies to provide general representativeness.

Relevância:

60.00% 60.00%

Publicador:

Resumo:

Objective To explore how different aspects of the professional environment for Australian community pharmacists are perceived to be influencing the effectiveness of continuing education models in improving practice.

Setting Australian community pharmacy.

Methods A convenience sample of practising community pharmacists (n = 15) was recruited using the 'snowballing' technique to participate in one of four focus group teleconferences. Each focus group examined continuing education experiences from different professional perspectives and training needs (recent graduates, experienced practitioners, specialist practitioners and rural/remote practitioners).

Key findings Facilitation of professional development by accreditation bodies, and new challenges resulting from the introduction of cognitive services were seen to promote a favourable environment for continuing education engagement. Complex continuing education delivery models combined with high costs and excessive workloads made it more difficult to engage with continuing education systems or try to apply knowledge to the workplace.

Conclusion Results support findings from previous research that practice development requires a multifaceted approach with continuing education as just one component. Affordable and integrated models of continuing education are required in order to optimise efficacy for participants.

Relevância:

60.00% 60.00%

Publicador:

Resumo:

This paper explores the implementation of a creativity support system (CSS) for tertiary students studying Games Design and Development at Deakin University, Victoria, Australia. The students at the centre of this study are the ‘next’ generation of learners and are often called the Internet generation because of their pre-imposed for ‘online’ and being ‘connected’. The CSS for the games students is designed within a context that encompasses a ‘whole’ system, as focusing on only one component to augment a person’s creativity does not take into consideration the multitude of factors, for example social factors, that are pertinent on a person ability to grow their creative behaviours. This study will present a set of factors that each CSS should employ to facilitate creative abilities within people, with particular focus on how social activities help to enhance creativity.

Relevância:

60.00% 60.00%

Publicador:

Resumo:

Purpose – The purpose of this paper is to propose a new model of corporate governance that is holistic – incorporating internal and macro perspectives across legal, regulatory, sociological, ethical, human resource management, behavioural and corporate strategic frameworks. Researchers have signalled the need for “new theoretical perspectives and new models of governance” due to a dearth of research that is context-driven, empirical, and encapsulating the full spectrum of reasons and actions contributing to corporate crises.

Design/methodology/approach – The approach consists of theory building by reviewing the literature and examining the gaps and limitations.

Findings – The proposed model is a distinctive contribution to theory and practice in three ways. First, it integrates the firm-specific, micro factors with the country-specific, macro factors to illustrate the holistic nature of corporate governance. Second, shareholders and stakeholders are shown to be only one component of the model. Third, it veers away from singular approaches, to dealing with corporate governance using a multi-disciplinary perspective. The paper argues that such a holistic and integrated view is a necessity for understanding governance systems.

Research limitations/implications – The challenge is to operationalize the model and test it empirically.

Practical implications – The model is instructive and of use for practitioners in attempting to understand, explain and develop governance models that are appropriate to their national and industry settings.

Originality/value
– This paper argues that narrow-based models are limited in their approach and in a sound and integrative review of the up-to-date literature contributes to theory-building on corporate governance.

Relevância:

60.00% 60.00%

Publicador:

Resumo:

This paper discusses the development of a new Bachelor of Education (Middle Years of Schooling) at The University of Queensland. The middle years of schooling have increasingly been the focus of education reform initiatives in Australia, but this has not been accompanied by significant increases in the number of teacher education institutions offering specialised middle schooling-level teacher preparation programmes. Considering the rapidly changing social and economic context and the emergent state of middle schooling in Australia, the programme represented a conceptual and practical opportunity and challenge for The University of Queensland team. Working collaboratively, the team sought to design a teacher education preservice programme that was both responsive and generative: that is, responsive to local school contexts and to current educational research and reform at national and international levels; and generative of cutting-edge theories and practices associated with middle schooling, teachers' work, and teacher education. This paper focuses on one component of the Middle Years of Schooling Teacher Education programme at The University of Queensland; namely, the practicum. We first present the underlying principles of the practicum programme and then examine "dilemmas" that emerged early in the practicum. These issues and tensions were associated with the ideals of "middle years" philosophy and the pragmatics of school reform associated with that new approach. In this paper, and within this context, we explore what it means to be both responsive and generative, and describe how we as teacher educators negotiated between the extremes these terms implied.

Relevância:

60.00% 60.00%

Publicador:

Resumo:

The electronic revolution has proven to be a powerful stimulus for change in business practice. As a business tool however, the Internet must endure the same scrutiny under which other business activities are placed. If the use of the Internet in business is a sound strategy, then it must contribute toward competitive advantage. The sport business industry has not been isolated from the vagaries of Internet applications. Moreover, as the industry has become more competitive, forcing sporting organisations towards unprecedented levels of accountability and business practice, the Internet has been increasingly seen as a potential 'holy grail' for sport organisations struggling for revenue (Stewart & Smith, 1999). This research is a response to these pressures. It seeks to identify Internet based opportunities for competitive advantage, and to provide strategies and recommendations for the successful use of the Internet in Australian professional sport organisations. In realising this objective, a newly developed and integrated Business Activity Model has been constructed. The model assists in the identification of specific Internet based competitive advantage strategies, and provides a theoretical framework for this research. The Business Activity Model conceptualises, for the first time, the relationships between the value chain, constituents of electronically enabled competitive advantage, and the Internet. With Australia's limited group of fully professional sports capable of sustaining the human resources and budgets necessary to implement comprehensive e-commerce strategies, the organisations selected to participate in this research represent the pinnacle of Australian professional sport clubs. Specifically, the 55 clubs competing in the Australian Football League (A.F.L.), National Basketball League (N.B.L.), National Rugby League (N.R.L.), and National Soccer League (N.S.L.) constituted the research sample and population. In concert with the 87% participation rate, sampling approached a census. A telephone-administered survey, based primarily on the rigorously tested instrument developed by Sethi and King (1994), was employed for data collection. This research employs a comprehensive set of descriptive statistics, and is bolstered by a confirmatory and an exploratory factor analysis, undertaken on one component of the data. The outcome of this research was the identification of seven practical recommendations for Australian professional sport organisations seeking to improve competitive advantage via the Internet. These recommendations were based on an inventory of the 'gaps' between the strategies proposed by the literature, and the practices of the sample, and relate to both overall Internet strategy, and specific web site applications. The development of the new Business Activity Model and the identification of key online strategy themes support and complement these recommendations. An examination of variations in the practices of participating organisations, and some comparisons against United States sporting organisations, also provides depth and context to the findings. This research provides a platform for sport managers to effectively harness the potential of the Internet, through their web sites in particular, and realise significant competitive advantages. The Business Activity Model provides managers in all industries with a tool for the detection and understanding of potential elements of competitive advantage, and incorporates all activities critical to business in the new digital economy. Seven practical recommendations for improved online performance based on identified competitive advantage and strategies fulfils the primary objective of this research. E-commerce continues to grow at astronomical rates, and with the Internet poised to become the life-blood of 21st century sporting organisations, these recommendations will assist managers in their ongoing search for competitive advantage.