41 resultados para Cantù, Cesare, 1804-1895.


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Recent studies have detected a dominant accumulation mode (~100 nm) in the Sea Spray Aerosol (SSA) number distribution. There is evidence to suggest that particles in this mode are composed primarily of organics. To investigate this hypothesis we conducted experiments on NaCl, artificial SSA and natural SSA particles with a Volatility-Hygroscopicity-Tandem-Differential-Mobility-Analyser (VH-TDMA). NaCl particles were atomiser generated and a bubble generator was constructed to produce artificial and natural SSA particles. Natural seawater samples for use in the bubble generator were collected from biologically active, terrestrially-affected coastal water in Moreton Bay, Australia. Differences in the VH-TDMA-measured volatility curves of artificial and natural SSA particles were used to investigate and quantify the organic fraction of natural SSA particles. Hygroscopic Growth Factor (HGF) data, also obtained by the VH-TDMA, were used to confirm the conclusions drawn from the volatility data. Both datasets indicated that the organic fraction of our natural SSA particles evaporated in the VH-TDMA over the temperature range 170–200°C. The organic volume fraction for 71–77 nm natural SSA particles was 8±6%. Organic volume fraction did not vary significantly with varying water residence time (40 secs to 24 hrs) in the bubble generator or SSA particle diameter in the range 38–173 nm. At room temperature we measured shape- and Kelvin-corrected HGF at 90% RH of 2.46±0.02 for NaCl, 2.35±0.02 for artifical SSA and 2.26±0.02 for natural SSA particles. Overall, these results suggest that the natural accumulation mode SSA particles produced in these experiments contained only a minor organic fraction, which had little effect on hygroscopic growth. Our measurement of 8±6% is an order of magnitude below two previous measurements of the organic fraction in SSA particles of comparable sizes. We stress that our results were obtained using coastal seawater and they can’t necessarily be applied on a regional or global ocean scale. Nevertheless, considering the order of magnitude discrepancy between this and previous studies, further research with independent measurement techniques and a variety of different seawaters is required to better quantify how much organic material is present in accumulation mode SSA.

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Despite recent public attention to e-health as a solution to rising healthcare costs and an ageingpopulation, there have been relatively few studies examining the geographical pattern of e-health usage. This paper argues for an equitable approach to e-health and attention to the way in which e-health initiatives can produce locational health inequalities, particularly in socioeconomically disadvantaged areas. In this paper, we use a case study to demonstrate geographical variation in Internet accessibility, Internet status and prevalence of chronic diseases within a small district. There are signifi cant disparities in access to health information within socioeconomically disadvantaged areas. The most vulnerable people in these areas are likely to have limited availability of, or access to Internet healthcare resources. They are also more likely to have complex chronic diseases and, therefore, be in greatest need of these resources. This case study demonstrates the importance of an equitable approach to e-health information technologies and telecommunications infrastructure.

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In this world of continuous change, there’s probably one certainty: more change lies ahead. Our students will encounter challenges and opportunities that we can’t even imagine. How do we prepare our students as future citizens for the challenges of the 21st century? One of the most influential public intellectuals of our time, Howard Gardner, suggests that in the future individuals will depend to a great extent on the capacity to synthesise large amounts of information. ‘They will need to be able to gather together information from disparate sources and put it together in ways that work for themselves and can be communicated to other persons’(Gardner 2008, p. xiii). One of the first steps in ‘putting things together’ so they ‘work’ in the mind is ‘to group objects and events together on the basis of some similarity between them’ (Lee & das Gupta 1995, p. 116). When we do this and give them a collective name, we are conceptualising. Apart from helping to save our sanity by simplifying the vast amounts of data we encounter every day, concepts help us to understand and gain meaning from what we experience. Concepts are essential for synthesising information and they also help us to communicate with others. Put simply, concepts serve as building blocks for knowledge, understanding and communication. This chapter addresses the importance of teaching and learning about concepts and conceptual development in studies of society and environment. It proceeds as follows: first, it considers how individuals use concepts, and, second, it explores the characteristics of concepts; the third section presents a discussion of approaches that might be adopted by teachers intending to help their students build concepts in the classroom.

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There are many reasons why interface design for interactive courseware fails to support quality of learning experiences. The causes such as the level of interactivity, the availability of the interfaces to interact with the end users and a lack of deep knowledge about the role of interface design by the designers in the development process are most acknowledged. Related to this, as a creator for the interactive courseware, generally the developers expect the resources that they produced are effective, accurate and robust. However, rarely do the developers have the opportunity to create good interfaces with the emphasis on time consuming, money and skill. Thus, some challenges faces by them in the interface design development can’t be underestimated as well. Therefore, their perspective of the interactive courseware is important to ensure the material and also the features of the interactive courseware can facilitate teaching and learning activity. Within this context in mind, this paper highlights the challenges that faces by the Malaysian developer from the ten face to face interviewed data gathered. It discusses from the Malaysian developer perspectives that involved in the development of interface design for interactive courseware for the Smart School Project. Particularly, in creating such a great interfaces, the highlights challenges will present within the constraints of time, curriculum demand, and competencies of the development team.

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To obtain minimum time or minimum energy trajectories for robots it is necessary to employ planning methods which adequately consider the platform’s dynamic properties. A variety of sampling, graph-based or local receding-horizon optimisation methods have previously been proposed. These typically use simplified kino-dynamic models to avoid the significant computational burden of solving this problem in a high dimensional state-space. In this paper we investigate solutions from the class of pseudospectral optimisation methods which have grown in favour amongst the optimal control community in recent years. These methods have high computational efficiency and rapid convergence properties. We present a practical application of such an approach to the robot path planning problem to provide a trajectory considering the robot’s dynamic properties. We extend the existing literature by augmenting the path constraints with sensed obstacles rather than predefined analytical functions to enable real world application.

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It is predicted that with increased life expectancy in the developed world, there will be a greater demand for synthetic materials to repair or regenerate lost, injured or diseased bone (Hench & Thompson 2010). There are still few synthetic materials having true bone inductivity, which limits their application for bone regeneration, especially in large-size bone defects. To solve this problem, growth factors, such as bone morphogenetic proteins (BMPs), have been incorporated into synthetic materials in order to stimulate de novo bone formation in the center of large-size bone defects. The greatest obstacle with this approach is that the rapid diffusion of the protein from the carrier material, leading to a precipitous loss of bioactivity; the result is often insufficient local induction or failure of bone regeneration (Wei et al. 2007). It is critical that the protein is loaded in the carrier material in conditions which maintains its bioactivity (van de Manakker et al. 2009). For this reason, the efficient loading and controlled release of a protein from a synthetic material has remained a significant challenge. The use of microspheres as protein/drug carriers has received considerable attention in recent years (Lee et al. 2010; Pareta & Edirisinghe 2006; Wu & Zreiqat 2010). Compared to macroporous block scaffolds, the chief advantage of microspheres is their superior protein-delivery properties and ability to fill bone defects with irregular and complex shapes and sizes. Upon implantation, the microspheres are easily conformed to the irregular implant site, and the interstices between the particles provide space for both tissue and vascular ingrowth, which are important for effective and functional bone regeneration (Hsu et al. 1999). Alginates are natural polysaccharides and their production does not have the implicit risk of contamination with allo or xeno-proteins or viruses (Xie et al. 2010). Because alginate is generally cytocompatible, it has been used extensively in medicine, including cell therapy and tissue engineering applications (Tampieri et al. 2005; Xie et al. 2010; Xu et al. 2007). Calcium cross-linked alginate hydrogel is considered a promising material as a delivery matrix for drugs and proteins, since its gel microspheres form readily in aqueous solutions at room temperature, eliminating the need for harsh organic solvents, thereby maintaining the bioactivity of proteins in the process of loading into the microspheres (Jay & Saltzman 2009; Kikuchi et al. 1999). In addition, calcium cross-linked alginate hydrogel is degradable under physiological conditions (Kibat PG et al. 1990; Park K et al. 1993), which makes alginate stand out as an attractive candidate material for the protein carrier and bone regeneration (Hosoya et al. 2004; Matsuno et al. 2008; Turco et al. 2009). However, the major disadvantages of alginate microspheres is their low loading efficiency and also rapid release of proteins due to the mesh-like networks of the gel (Halder et al. 2005). Previous studies have shown that a core-shell structure in drug/protein carriers can overcome the issues of limited loading efficiencies and rapid release of drug or protein (Chang et al. 2010; Molvinger et al. 2004; Soppimath et al. 2007). We therefore hypothesized that introducing a core-shell structure into the alginate microspheres could solve the shortcomings of the pure alginate. Calcium silicate (CS) has been tested as a biodegradable biomaterial for bone tissue regeneration. CS is capable of inducing bone-like apatite formation in simulated body fluid (SBF) and its apatite-formation rate in SBF is faster than that of Bioglass® and A-W glass-ceramics (De Aza et al. 2000; Siriphannon et al. 2002). Titanium alloys plasma-spray coated with CS have excellent in vivo bioactivity (Xue et al. 2005) and porous CS scaffolds have enhanced in vivo bone formation ability compared to porous β-tricalcium phosphate ceramics (Xu et al. 2008). In light of the many advantages of this material, we decided to prepare CS/alginate composite microspheres by combining a CS shell with an alginate core to improve their protein delivery and mineralization for potential protein delivery and bone repair applications

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Techniques for the accurate measurement of ionising radiation have been evolving since Roentgen first discovered x-rays in 1895; until now experimental measurements of radiation fields in the three spatial dimensions plus time have not been successfully demonstrated. In this work, we embed an organic plastic scintillator in a polymer gel dosimeter to obtain the first quasi-4D experimental measurement of a radiation field.

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Background: Chronic diseases including type 2 diabetes are a leading cause of morbidity and mortality in midlife and older Australian women. There are a number of modifiable risk factors for type 2 diabetes and other chronic diseases including smoking, nutrition, physical activity and overweight and obesity. Little research has been conducted in the Australian context to explore the perceived barriers to health promotion activities in midlife and older Australian women with a chronic disease. Aims: The primary aim of this study was to explore women’s perceived barriers to health promotion activities to reduce modifiable risk factors, and the relationship of perceived barriers to smoking behaviour, fruit and vegetable intake, physical activity and body mass index. A secondary aim of this study was to investigate nurses’ perceptions of the barriers to action for women with a chronic disease, and to compare those perceptions with those of the women. Methods: The study was divided into two phases where Phase 1 was a cross sectional survey of women, aged over 45 years with type 2 diabetes who were attending Diabetes clinics in the Primary and Community Health Service of the Metro North Health Service District of Queensland Health (N = 22). The women were a subsample of women participating in a multi-model lifestyle intervention, the ‘Reducing Chronic Disease among Adult Australian Women’ project. Phase 2 of the study was a cross sectional online survey of nurses working in Primary and Community Health Service in the Metro North Health Service District of Queensland Health (N = 46). Pender’s health promotion model was used as the theoretical framework for this study. Results: Women in this study had an average total barriers score of 32.18 (SD = 9.52) which was similar to average scores reported in the literature for women with a range of physical disabilities and illnesses. The leading five barriers for this group of women were: concern about safety; too tired; not interested; lack of information about what to do; with lack of time and feeling I can’t do things correctly the equal fifth ranked barriers. In this study there was no statistically significant difference in average total barriers scores between women in the intervention group and those is the usual care group of the parent study. There was also no significant relationship between the women’s socio-demographic variables and lifestyle risk factors and their level of perceived barriers. Nurses in the study had an average total barriers score of 44.48 (SD = 6.24) which was higher than all other average scores reported in the literature. The leading five barriers that nurses perceived were an issue for women with a chronic disease were: lack of time and interferes with other responsibilities the leading barriers; embarrassment about appearance; lack of money; too tired and lack of support from family and friends. There was no significant relationship between the nurses’ sociodemographic and nursing variables and the level of perceived barriers. When comparing the results of women and nurses in the study there was a statistically significant difference in the median total barriers score between the groups (p < 0.001), where the nurses perceived the barriers to be higher (Md = 43) than the women (Md = 33). There was also a significant difference in the responses to the individual barriers items in fifteen of the eighteen items (p < 0.002). Conclusion: Although this study is limited by a small sample size, it contributes to understanding the perception of midlife and older women with a chronic disease and also the perception of nurses, about the barriers to healthy lifestyle activities that women face. The study provides some evidence that the perceptions of women and nurses may differ and argues that these differences may have significant implications for clinical practice. The study recommends a greater emphasis on assessing and managing perceived barriers to health promotion activities in health education and policy development and proposes a conceptual model for understanding perceived barriers to action.

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In early 2011, the Australian Learning and Teaching Council Ltd (ALTC) commissioned a series of Good Practice Reports on completed ALTC projects and fellowships. This report will: • Provide a summative evaluation of the good practices and key outcomes for teaching and learning from completed ALTC projects and fellowships relating to blended learning • Include a literature review of the good practices and key outcomes for teaching and learning from national and international research • Identify areas in which further work or development are appropriate. The literature abounds with definitions; it can be argued that the various definitions incorporate different perspectives, but there is no single, collectively accepted definition. Blended learning courses in higher education can be placed somewhere on a continuum, between fully online and fully face-to-face courses. Consideration must therefore be given to the different definitions for blended learning presented in the literature and by users and stakeholders. The application of this term in these various projects and fellowships is dependent on the particular focus of the team and the conditions and situations under investigation. One of the key challenges for projects wishing to develop good practice in blended learning is the lack of a universally accepted definition. The findings from these projects and fellowships reveal the potential of blended learning programs to improve both student outcomes and levels of satisfaction. It is clear that this environment can help teaching and learning engage students more effectively and allow greater participation than traditional models. Just as there are many definitions, there are many models and frameworks that can be successfully applied to the design and implementation of such courses. Each academic discipline has different learning objectives and in consequence there can’t be only one correct approach. This is illustrated by the diversity of definitions and applications in the ALTC funded projects and fellowships. A review of the literature found no universally accepted guidelines for good practice in higher education. To inform this evaluation and literature review, the Seven Principles for Good Practice in Undergraduate Education, as outlined by Chickering and Gamson (1987), were adopted: 1. encourages contacts between students and faculty 2. develops reciprocity and cooperation among students 3. uses active learning techniques 4. gives prompt feedback 5. emphasises time on task 6. communicates high expectations 7. respects diverse talents and ways of learning. These blended learning projects have produced a wide range of resources that can be used in many and varied settings. These resources include: books, DVDs, online repositories, pedagogical frameworks, teaching modules. In addition there is valuable information contained in the published research data and literature reviews that inform good practice and can assist in the development of courses that can enrich and improve teaching and learning.

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Biomass and non-food crop residues are seen as relatively low cost and abundant renewable sources capable of making a large contribution to the world’s future energy and chemicals supply. Signifi cant quantities of ethanol are currently produced from biomass via biochemical processes, but thermochemical conversion processes offer greater potential to utilize the entire biomass source to produce a range of products. This chapter will review thermochemical gasifi cation and pyrolysis methods with a focus on hydrothermal liquefaction processes. Hydrothermal liquefaction is the most energetically advantageous thermochemical biomass conversion process. If the target is to produce sustainable liquid fuels and chemicals and reduce the impact of global warming as a result of carbon dioxide, nitrous oxide, and methane emissions (i.e., protect the natural environment), the use of “green” solvents, biocatalysts and heterogeneous catalysts must be the main R&D initiatives. As the biocrude produced from hydrothermal liquefaction is a complex mixture which is relatively viscous, corrosive, and unstable to oxidation (due to the presence of water and oxygenated compounds), additional upgrading processes are required to produce suitable biofuels and chemicals.

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Born in 1895, Alan Johnston Campbell was a grazier and political party organiser. In December 1914 he enlisted in the Australian Imperial Force and saw action with the 2nd Light Horse Regiment at Gallipoli and, as a lance corporal, in the Sinai and Palestine. After the war Campbell became active in the Roma branch of the Maranoa Graziers’ Association. In 1935, at Roma, he formed one of the first branches of the Queensland Country Party. In 1943, Campbell was elected president of the QCP. Impressed by the Australian Labor Party’s organisation, Campbell centralised power and rebuked parliamentarians whom he believed were neglecting their constituents. By 1951 the highly disciplined structure had attracted 35,000 members. Campbell died in 1982.

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Understanding the impacts of traffic and climate change on water quality helps decision makers to develop better policy and plans for dealing with unsustainable urban and transport development. This chapter presents detailed methodologies developed for sample collection and testing for heavy metals and total petroleum hydrocarbons, as part of a research study to investigate the impacts of climate change and changes to urban traffic characteristics on pollutant build-up and wash-off from urban road surfaces. Cadmium, chromium, nickel, copper, lead, iron, aluminium, manganese and zinc were the target heavy metals, and selected gasoline and diesel range organics were the target total petroleum hydrocarbons for this study. The study sites were selected to encompass the urban traffic characteristics of the Gold Coast region, Australia. An improved sample collection method referred to as ‘the wet and dry vacuum system’ for the pollutant build-up, and an effective wash-off plan to incorporate predicted changes to rainfall characteristics due to climate change, were implemented. The novel approach to sample collection for pollutant build-up helped to maintain the integrity of collection efficiency. The wash-off plan helped to incorporate the predicted impacts of climate change in the Gold Coast region. The robust experimental methods developed will help in field sample collection and chemical testing of different stormwater pollutants in build-up and wash-off.

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Many existing information retrieval models do not explicitly take into account in- formation about word associations. Our approach makes use of rst and second order relationships found in natural language, known as syntagmatic and paradigmatic associ- ations, respectively. This is achieved by using a formal model of word meaning within the query expansion process. On ad hoc retrieval, our approach achieves statistically sig- ni cant improvements in MAP (0.158) and P@20 (0.396) over our baseline model. The ERR@20 and nDCG@20 of our system was 0.249 and 0.192 respectively. Our results and discussion suggest that information about both syntagamtic and paradigmatic associa- tions can assist with improving retrieval eectiveness on ad hoc retrieval.

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In this paper, we propose a novel direction for gait recognition research by proposing a new capture-modality independent, appearance-based feature which we call the Back-filled Gait Energy Image (BGEI). It can can be constructed from both frontal depth images, as well as the more commonly used side-view silhouettes, allowing the feature to be applied across these two differing capturing systems using the same enrolled database. To evaluate this new feature, a frontally captured depth-based gait dataset was created containing 37 unique subjects, a subset of which also contained sequences captured from the side. The results demonstrate that the BGEI can effectively be used to identify subjects through their gait across these two differing input devices, achieving rank-1 match rate of 100%, in our experiments. We also compare the BGEI against the GEI and GEV in their respective domains, using the CASIA dataset and our depth dataset, showing that it compares favourably against them. The experiments conducted were performed using a sparse representation based classifier with a locally discriminating input feature space, which show significant improvement in performance over other classifiers used in gait recognition literature, achieving state of the art results with the GEI on the CASIA dataset.