396 resultados para Anisotropic exchange interaction
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Sewer main chokes (blockages) are a key performance indicator for Australian water utilities. Blockages caused by tree roots often result in wastewater overflow posing an environmental and health risk and also requiring service interruptions to repair asset. The purpose of the research project outlined in this paper was to understand the role of environmental parameters, in particular soil type and tree density, in determining the propensity of a sewer to become blocked. The paper demonstrates the application of spatial analysis to inform and communicate the results of the analysis. GIS was used to explore the relationship between tree density and previously recorded sewer blockages for a Melbourne utility. Initial results from the research reveal a relationship between increased tree densities and occurrence of sewer blockages. An improved understanding of the influence of environmental parameters on the inherent risk of sewer blockage will enable asset managers to identify those assets requiring proactive management in order to minimise service interruptions, repairs and environmental impacts.
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Trade flows of commodities are generally affected by the principles of comparative advantage in a free trade. However, trade flows might be enhanced or distorted not only by various government interventions, but also by exchange rate fluctuations among others. This study applies a commodity-specific gravity model to selected vegetable trade flows among Organization for Economic Co-operation and Development (OECD) countries to determine the effects of exchange rate uncertainty on the trade flows. Using the data from 1996 to 2002, the results show that, while the exchange rate uncertainty significantly reduces trade in the majority of commodity flows, there is evidence that both short- and long-term volatility have positive effect on trade flows of specific commodities. This study also tests the regional preferential trade agreements such as the North American Free Trade Agreement (NAFTA), the Asia-Pacific Economic Cooperation (APEC) and the EU, and their different effects on commodities.
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This research provides validated Finite Element techniques to analyse pile foundations under seismic loads. The results show that the capability of the technique to capture the important pile response which includes kinematic and inertial interaction effects, effects of soil stiffness and depth on pile deflection patterns and permanent deformations.
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Negative board diversity-organizational outcomes research findings have highlighted the importance of studying board demographic faultlines. Based on research gaps, this study focuses on gender diversity, age diversity, board size and faultlines formation in corporate boards. It proposes a positive linear diversity-faultlines relationship based on self-categorization and social identity theories, interaction effects of gender diversity and age diversity on faultlines based on contingency theories, and a U-shaped board size-faultlines strength relationship. The hypotheses were tested in 288 large companies listed on the Australian Securities Exchange using archival data. The results provided partial support for the interaction effects relationships and support to the U-shaped board size-faultlines strength relationship. The findings indicate that boards with low levels of age diversity experience a negative linear relationship between gender diversity and faultlines such that higher representation of women leads to weaker faultlines. The results also suggest that small- and large-sized boards experience stronger faultlines strength than medium-sized board. These results inform practice and underline implications of board demographic diversity and board size.
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Interactions of chemicals with the microtubular network of cells may lead to genotoxicity. Micronuclei (MN) might be caused by interaction of metals with tubulin and/or kinesin. The genotoxic effects of inorganic lead and mercury salts were studied using the MN assay and the CREST analysis in V79 Chinese hamster fibroblasts. Effects on the functional activity of motor protein systems were examined by measurement of tubulin assembly and kinesin-driven motility. Lead and mercury salts induced MN dose-dependently. The no-effect-concentration for MN induction was 1.1 μM PbCl2, 0.05 μM Pb(OAc)2 and 0.01 μM HgCl2. The in vitro results obtained for PbCl2 correspond to reported MN induction in workers occupationally exposed to lead, starting at 1.2 μM Hg(II) (Vaglenov et al., 2001, Environ. Health Perspect. 109, 295-298). The CREST Analysis indicate aneugenic effects of Pb(II) and aneugenic and additionally clastogenic effects of Hg(II). Lead (chloride, acetate, and nitrate) and mercury (chloride and nitrate) interfered dose-dependently with tubulin assembly in vitro. The no-effect-concentration for lead salts in this assay was 10 μM. Inhibition of tubulin assembly by mercury started at 2 μM. The gliding velocity of microtubules along immobilised kinesin molecules was affected by 25 μM Pb(NO3)2 and 0.1 μM HgCl2 in a dose-dependent manner. Our data support the hypothesis that lead and mercury genotoxicity may result, at least in part, via disturbance of chromosome segregation via interaction with cytoskeletal proteins.
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Various forms of hydrogenated graphene have been produced to date by several groups, while the synthesis of pure graphane has not been achieved yet. The study of the interface between graphane, in all its possible hydrogenation configurations, and catalyst metal surfaces can be pivotal to assess the feasibility of direct CVD growth methods for this material. We investigated the adhesion of graphane to a Cu(111) surface by adopting the vdW-DF2-C09 exchange-correlation functional, which is able to describe dispersion forces. The results are further compared with the PBE and the LDA exchange-correlation functionals. We calculated the most stable geometrical configurations of the slab/graphane interface and evaluated how graphane's geometrical parameters are modified. We show that dispersion forces play an important role in the slab/graphane adhesion. Band structure calculations demonstrated that in the presence of the interaction with copper, the band gap of graphane is not only preserved, but also enlarged, and this increase can be attributed to the electronic charge accumulated at the interface. We calculated a substantial energy barrier at the interface, suggesting that CVD graphane films might act as reliable and stable insulating thin coatings, or also be used to form compound layers in conjunction with metals and semiconductors.
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Archaeology has been called 'the science of the artefact' and nothing demonstrates this point better than the current interest displayed in provenance studies of archaeological objects. In theory, every vessel carries a chemical compositional pattern or 'fingerprint' identical with the clay from which it was made and this relationship is basic to provenance studies. The reasoning behind provenance or sourcing studies is to probe into this past and attempt to re-create prehistory by obtaining information on exchange and social interaction. This paper discusses the use of XRF spectrometry for the analysis of ancient pottery and ceramics to examine whether it is possible to predict prehictoric cultural exchanges.
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Early parenting is critical to effective attachment and a range of positive developmental outcomes for children. Feeding is a key task of early parenting and increasing evidence indicates that early feeding practices are important for the development of self-regulation of intake and food preferences which in turn are predictors of later obesity risk. However, relatively little is known about the mother-infant interaction at the transition to solids among typically developing children. This study aimed to describe parenting strategies used by mothers at the transition from milk feeding to solid food. Twenty mother-infant dyads were video-taped during a feeding interaction and data was analysed to describe maternal use of parenting strategies. It was predicted that positive feeding strategies would be correlated with lower levels of Infant Food Refusal (IFR), higher maternal sensitivity, and better overall parenting scores. The opposite was predicted for negative feeding strategies. It was found that positive strategy use and general parenting scores were significantly correlated in the predicted direction, however maternal instruction, aversive contact and ineffective strategy use were significantly correlated with and predictive of IFR. Additionally, it was hypothesised that maternal strategy use would deteriorate towards the end of the interaction, and this hypothesis was partially supported: significantly more negative strategy use was observed in the last third of the interaction, whilst positive strategy use remained consistent through the feeding interaction. The findings have important implications for early feeding parent education and intervention programs.
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Health Information Exchange (HIE) is an interesting phenomenon. It is a patient centric health and/or medical information management scenario enhanced by integration of Information and Communication Technologies (ICT). While health information systems are repositioning complex system directives, in the wake of the ‘big data’ paradigm, extracting quality information is challenging. It is anticipated that in this talk, ICT enabled healthcare scenarios with big data analytics will be shared. In addition, research and development regarding big data analytics, such as current trends of using these technologies for health care services and critical research challenges when extracting quality of information to improve quality of life will be discussed.
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Spatial variation of seismic ground motions is caused by incoherence effect, wave passage, and local site conditions. This study focuses on the effects of spatial variation of earthquake ground motion on the responses of adjacent reinforced concrete (RC) frame structures. The adjacent buildings are modeled considering soil-structure interaction (SSI) so that the buildings can be interacted with each other under uniform and non-uniform ground motions. Three different site classes are used to model the soil layers of SSI system. Based on fast Fourier transformation (FFT), spatially correlated non-uniform ground motions are generated compatible with known power spectrum density function (PSDF) at different locations. Numerical analyses are carried out to investigate the displacement responses and the absolute maximum base shear forces of adjacent structures subjected to spatially varying ground motions. The results are presented in terms of related parameters affecting the structural response using three different types of soil site classes. The responses of adjacent structures have changed remarkably due to spatial variation of ground motions. The effect can be significant on rock site rather than clay site.