959 resultados para Adaptive feeding behaviour


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Background The overrepresentation of young drivers in road crashes, injuries and fatalities around the world has resulted in a breadth of injury prevention efforts including education, enforcement, engineering, and exposure control. Despite multifaceted intervention, the young driver problem remains a challenge for injury prevention researchers, practitioners and policy-makers. The intractable nature of young driver crash risks suggests that a deeper understanding of their car use – that is, the purpose of their driving – is required to inform the design of more effective young driver countermeasures. Aims This research examined the driving purpose reported by young drivers, including the relationship with self-reported risky driving behaviours including offences. Methods Young drivers with a Learner or Provisional licence participated in three online surveys (N1 = 656, 17–20 years; N2 = 1051, 17–20 years; N3 = 351, 17–21 years) as part of a larger state-wide project in Queensland, Australia. Results A driving purpose scale was developed (the PsychoSocial Purpose Driving Scale, PSPDS), revealing that young drivers drove for psychosocial reasons such as for a sense of freedom and to feel independent. Drivers who reported the greatest psychosocial purpose for driving were more likely to be male and to report more risky driving behaviours such as speeding. Drivers who deliberately avoided on-road police presence and reported a prior driving-related offence had significantly greater PSPDS scores, and higher reporting of psychosocial driving purposes was found over time as drivers transitioned from the supervised Learner licence phase to the independent Provisional (intermediate) licence phase. Discussion and conclusions The psychosocial needs met by driving suggest that effective intervention to prevent young driver injury requires further consideration of their driving purpose. Enforcement, education, and engineering efforts which consider the psychosocial purpose of the driving are likely to be more efficacious than those which presently do not. Road safety countermeasures could reduce the young driver’s exposure to risk through such mechanisms as encouraging the use of public transport.

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This chapter is focussed on the research and development of an intelligent driver warning system (IDWS) as a means to improve road safety and driving comfort. Two independent IDWS case studies are presented. The first study examines the methodology and implementation for attentive visual tracking and trajectory estimation for dynamic scene segmentation problems. In the second case study, the concept of driver modelling is evaluated which can be used to provide useful feedback to drivers. In both case studies, the quality of IDWS is largely determined by the modelling capability for estimating multiple vehicle trajectories and modelling driving behaviour. A class of modelling techniques based on neural-fuzzy systems, which exhibits provable learning and modelling capability, is proposed. For complex modelling problems where the curse of dimensionality becomes an issue, a network construction algorithm based on Adaptive Spline Modelling of Observation Data (ASMOD) is also proposed.

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Problem The Manchester Driver Behaviour Questionnaire (DBQ) is the most commonly used self-report tool in traffic safety research and applied settings. It has been claimed that the violation factor of this instrument predicts accident involvement, which was supported by a previous meta-analysis. However, that analysis did not test for methodological effects, or include contacting researchers to obtain unpublished results. Method The present study re-analysed studies on prediction of accident involvement from DBQ factors, including lapses, and many unpublished effects. Tests of various types of dissemination bias and common method variance were undertaken. Results Outlier analysis showed that some effects were probably not reliable data, but excluding them did not change the results. For correlations between violations and crashes, tendencies for published effects to be larger than unpublished ones and for effects to decrease over time were observed, but were not significant. Also, analysis using the proxy of the mean of accidents in studies indicated that studies where effects for violations are unknown have smaller effect sizes. These differences indicate dissemination bias. Studies using self-reported accidents as dependent variables had much larger effects than those using recorded accident data. Also, zero-order correlations were larger than partial correlations that controlled for exposure. Similarly, violations/accidents effects were strong only when there was also a strong correlation between accidents and exposure. Overall, the true effect is probably very close to zero (r<.07) for violations versus traffic accident involvement, depending upon which systematic tendencies in the data are controlled for. Conclusions: Methodological factors and dissemination bias have inflated the mean effect size of the DBQ in the published literature. Strong evidence of various artefactual effects is apparent. Practical Applications A greater level of care should be taken if the DBQ continues to be used in traffic safety research. Also, validation of self-reports should be more comprehensive in the future, taking into account the possibility of common method variance.

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In The Climate Change Review, Ross Garnaut emphasised that ‘Climate change and climate change mitigation will bring about major structural change in the agriculture, forestry and other land use sectors’. He provides this overview of the effects of climate change on food demand and supply: ‘Domestic food production in many developing countries will be at immediate risk of reductions in agricultural productivity due to crop failure, livestock loss, severe weather events and new patterns of pests and diseases.’ He observes that ‘Changes to local climate and water availability will be key determinants of where agricultural production occurs and what is produced.’ Gert Würtenberger has commented that modern plant breeding is particularly concerned with addressing larger issues about nutrition, food security and climate change: ‘Modern plant breeding has an increasing importance with regard to the continuously growing demand for plants for nutritional and feeding purposes as well as with regard to renewal energy sources and the challenges caused by climate changes.’ Moreover, he notes that there is a wide array of scientific and technological means of breeding new plant varieties: ‘Apart from classical breeding, technologies have an important role in the development of plants that satisfy the various requirements that industrial and agricultural challenges expect to be fulfilled.’ He comments: ‘Plant variety rights, as well as patents which protect such results, are of increasingly high importance to the breeders and enterprises involved in plant development programmes.’ There has been larger interest in the intersections between sustainable agriculture, environmental protection and food security. The debate over agricultural intellectual property is a polarised one, particularly between plant breeders, agricultural biotechnology companies and a range of environmentalist groups. Susan Sell comments that there are complex intellectual property battles surrounding agriculture: 'Seeds are at the centre of a complex political dynamic between stakeholders. Access to seeds concerns the balance between private rights and public obligations, private ownership and the public domain, and commercial versus humanitarian objectives.' Part I of this chapter considers debates in respect of plant breeders’ rights, food security and climate change in relation to the UPOV Convention 1991. Part II explores efforts by agricultural biotechnology companies to patent climate-ready crops. Part III considers the report of the Special Rapporteur for Food, Olivier De Schutter. It looks at a variety of options to encourage access to plant varieties with climate adaptive or mitigating properties.

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Concrete-filled steel tubular (CFST) columns have shown great potential as axial load carrying member and used widely in many mission critical infrastructures. However, attention is needed to strengthen these members where transverse impact force is expected to occur due to vehicle collisions. In this work, finite element (FE) model of carbon fibre reinforced polymer (CFRP) strengthened CFST columns are developed and the effect of CFRP bond length is investigated under transverse impact loading. Initially the numerical models have been validated by comparing impact test results from literature. The validated models are then used for detail parametric studies by varying the length of externally bonded CFRP composites. The parameters considered for this research are impact velocity, impact mass, CFRP modulus, adhesive type, and axial static loading. It has been observed that the effect of CFRP strengthening is consistent after an optimum effective bond length of CFRP wrapping. The effect of effective bond length has been studied for above parameters. The results show that, under combined axial static and transverse impact loads CFST columns can successfully prevent global buckling failure by strengthening only 34% of column length. Therefore, estimation of effective bond length is essential to utilise the CFRP composites cost effectively.

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The benefits of virtual communities in increasing firms' profits, instilling knowledge in consumers, and enhancing consumers' social experience and enjoyment are widely recognised. However, relatively little is known about how the use of a virtual community could influence consumers' emotional well-being. This study examines the relationships among virtual community features (structural and experiential routes) as antecedents of virtual community engagement, including quality of use of virtual communities (time spent online and level of information exchange), electronic word-of-mouth (eWOM) purchasing behaviour, and consumers' emotional experience. Furthermore, by extending the cultural perspective to virtual community engagement, this study examines the role of collectivistic values on the aforementioned relationships. The proposed hypotheses are tested on the basis of data collected from 286 members of different virtual communities in Taiwan. The results partially support the theory that features of virtual communities influenced the quality of use, which then has a subsequent effect on consumer eWOM purchasing and emotional well-being. The results of the empirical analysis add credence to the proposed relationships. The role of collectivistic values is also partially supported. A detailed discussion of the findings and limitations of this study is provided.

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Service compositions enable users to realize their complex needs as a single request. Despite intensive research, especially in the area of business processes, web services and grids, an open and valid question is still how to manage service compositions in order to satisfy both functional and non-functional requirements as well as adapt to dynamic changes. In this paper we propose an (functional) architecture for adaptive management of QoS-aware service compositions. Comparing to the other existing architectures this one offers two major advantages. Firstly, this architecture supports various execution strategies based on dynamic selection and negotiation of services included in a service composition, contracting based on service level agreements, service enactment with flexible support for exception handling, monitoring of service level objectives, and profiling of execution data. Secondly, the architecture is built on the basis of well know existing standards to communicate and exchange data, which significantly reduces effort to integrate existing solutions and tools from different vendors. A first prototype of this architecture has been implemented within an EU-funded Adaptive Service Grid project. © 2006 Springer-Verlag.

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Background and purpose Adaptive radiotherapy (ART) can account for the dosimetric impact of anatomical change in head and neck cancer patients; however it can be resource intensive. Consequently, it is imperative that patients likely to require ART are identified. The purpose of this study was to find predictive factors that identify oropharyngeal squamous cell carcinoma (OPC) and nasopharyngeal carcinoma (NPC) patients more likely to need ART. Materials and methods One hundred and ten patients with OPC or NPC were analysed. Patient demographics and tumour characteristics were compared between patients who were replanned and those that were not. Factors found to be significant were included in logistic regression models. Risk profiles were developed from these models. A dosimetric analysis was performed. Results Nodal disease stage, pre-treatment largest involved node size, diagnosis and initial weight (categorised in 2 groups) were identified as significant for inclusion in the model. Two models were found to be significant (p = 0.001), correctly classifying 98.2% and 96.1% of patients respectively. Three ART risk profiles were developed. Conclusion Predictive factors identifying OPC or NPC patients more likely to require ART were reported. A risk profile approach could facilitate the effective implementation of ART into radiotherapy departments through forward planning and appropriate resource allocation.

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Phylogeographic patterns and population structure of the pelagic Indian mackerel, Rastrelliger kanagurta were examined in 23 populations collected from the Indonesian-Malaysian Archipelago (IMA) and the West Indian Ocean (WIO). Despite the vast expanse of the IMA and neighbouring seas, no evidence for geographical structure was evident. An indication that R. kanagurta populations across this region are essentially panmictic. This study also revealed that historical isolation was insufficient for R. kanagurta to attain migration drift equilibrium. Two distinct subpopulations were detected between the WIO and the IMA (and adjacent populations); interpopulation genetic variation was high. A plausible explanation for the genetic differentiation observed between the IMA and WIO regions suggest historical isolation as a result of fluctuations in sea levels during the late Pleistocene. This occurrence resulted in the evolution of a phylogeographic break for this species to the north of the Andaman Sea.

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Moffitt’s dual typology of ‘life-course persistent’ and ‘adolescence limited’ offending has received extensive empirical attention, but the extent to which the antisocial behaviour of adolescence limited offenders is constrained to adolescence is relatively under-examined.Using data from the Australian Mater University Study of Pregnancy and its Outcomes, we explore Moffitt’s concept of snares, or those factors that may lead to an adolescent persisting in antisocial behaviour such as drug addiction, educational failure, and contact with the justice system. The Mater University Study of Pregnancy and its Outcomes is a longitudinal study of mother–child dyads from the pre-natal stage to 21 years of age. Findings show that one-third of individuals identified as having an adolescent onset of antisocial behaviour persisted with this antisocial behaviour as young adults. This continuity can, in part, be explained by snares and the research suggests that reducing exposure to snares may lead to less antisocial behaviour in adulthood.

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The use of malathion in fruit fly protein bait sprays has raised serious concerns due to its adverse effects on non-target organisms. This has necessitated the evaluation of novel reduced-risk compounds. This study evaluated the effects of spinosad, fipronil, malathion and chlorpyrifos mixed with fruit fly protein bait (Mauri Pinnacle protein®) on attraction, feeding and mortality of the Queensland fruit fly, Bactrocera tryoni (Froggatt). The effects of outdoor weathering of these mixtures on fly mortality were also determined. In field-cage experiment, protein-starved flies showed the same level of attraction to baits containing spinosad, fipronil, malathion, chlorpyrifos and protein alone used as control. Female protein-starved flies were deterred from feeding on baits containing malathion and chlorpyrifos compared to baits containing spinosad, fipronil and protein alone. Baits containing malathion and chlorpyrifos caused higher fly mortality and rapid fly knock down than spinosad and fipronil. However, spinosad acted slowly and caused an increase in fly mortality over time, causing up to 90% fly mortality after 72-h. Baits containing malathion and chlorpyrifos, applied on citrus leaves and weathered outdoors, had longer residual effectiveness in killing flies than spinosad and fipronil. Residual effectiveness of the spinosad bait mixture waned significantly after 3 days of outdoor weathering. Results suggest that spinosad and fipronil can be potential alternatives for malathion in protein bait sprays.

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Scenario planning is a method widely used by strategic planners to address uncertainty about the future. However, current methods either fail to address the future behaviour and impact of stakeholders or they treat the role of stakeholders informally. We present a practical decision-analysis-based methodology for analysing stakeholder objectives and likely behaviour within contested unfolding futures. We address issues of power, interest, and commitment to achieve desired outcomes across a broad stakeholder constituency. Drawing on frameworks for corporate social responsibility (CSR), we provide an illustrative example of our approach to analyse a complex contested issue that crosses geographic, organisational and cultural boundaries. Whilst strategies can be developed by individual organisations that consider the interests of others – for example in consideration of an organisation's CSR agenda – we show that our augmentation of scenario method provides a further, nuanced, analysis of the power and objectives of all concerned stakeholders across a variety of unfolding futures. The resulting modelling framework is intended to yield insights and hence more informed decision making by individual stakeholders or regulators.

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Piezoelectric polymers based on polyvinylidene fluoride (PVDF) are of interest as smart materials for novel space-based telescope applications. Dimensional adjustments of adaptive thin polymer films are achieved via controlled charge deposition. Predicting their long-term performance requires a detailed understanding of the piezoelectric property changes that develop during space environmental exposure. The overall materials performance is governed by a combination of chemical and physical degradation processes occurring in low Earth orbit as established by our past laboratory-based materials performance experiments (see report SAND 2005-6846). Molecular changes are primarily induced via radiative damage, and physical damage from temperature and atomic oxygen exposure is evident as depoling, loss of orientation and surface erosion. The current project extension has allowed us to design and fabricate small experimental units to be exposed to low Earth orbit environments as part of the Materials International Space Station Experiments program. The space exposure of these piezoelectric polymers will verify the observed trends and their degradation pathways, and provide feedback on using piezoelectric polymer films in space. This will be the first time that PVDF-based adaptive polymer films will be operated and exposed to combined atomic oxygen, solar UV and temperature variations in an actual space environment. The experiments are designed to be fully autonomous, involving cyclic application of excitation voltages, sensitive film position sensors and remote data logging. This mission will provide critically needed feedback on the long-term performance and degradation of such materials, and ultimately the feasibility of large adaptive and low weight optical systems utilizing these polymers in space.

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Aerobic respiration is a fundamental energy-generating process; however, there is cost associated with living in an oxygen-rich environment, because partially reduced oxygen species can damage cellular components. Organisms evolved enzymes that alleviate this damage and protect the intracellular milieu, most notably thiol peroxidases, which are abundant and conserved enzymes that mediate hydrogen peroxide signaling and act as the first line of defense against oxidants in nearly all living organisms. Deletion of all eight thiol peroxidase genes in yeast (∆8 strain) is not lethal, but results in slow growth and a high mutation rate. Here we characterized mechanisms that allow yeast cells to survive under conditions of thiol peroxidase deficiency. Two independent ∆8 strains increased mitochondrial content, altered mitochondrial distribution, and became dependent on respiration for growth but they were not hypersensitive to H2O2. In addition, both strains independently acquired a second copy of chromosome XI and increased expression of genes encoded by it. Survival of ∆8 cells was dependent on mitochondrial cytochrome-c peroxidase (CCP1) and UTH1, present on chromosome XI. Coexpression of these genes in ∆8 cells led to the elimination of the extra copy of chromosome XI and improved cell growth, whereas deletion of either gene was lethal. Thus, thiol peroxidase deficiency requires dosage compensation of CCP1 and UTH1 via chromosome XI aneuploidy, wherein these proteins support hydroperoxide removal with the reducing equivalents generated by the electron transport chain. To our knowledge, this is the first evidence of adaptive aneuploidy counteracting oxidative stress.