996 resultados para velocity change


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Alamethicin, its derivatives and some synthetic fragments have been shown to be uncouplers of oxidative phosphorylation in rat liver mitochondria. A minimum peptide chain length of 13 residues is necessary for this activity. Peptide esters are more efficient uncouplers than the corresponding peptide acids. Esterification of the Glu(18) γ-COOH group in alamethicin does not diminish uncoupling activity. The structural requirements for uncoupling activity parallel those determined for ionophoretic action in small, unilamellar liposomes. Aib, α-aminoisobutyric acid; Z, benzyloxycarbonyl; OMe, methyl ester; OBz, benzyl ester; Ac, acetyl; CTC, chlortetracycline.

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A simple graphical method is presented for velocity and acceleration analysis of complex mechanisms possessing low or high degree of complexity. The method is iterative in character and generally yields the solution within a few iterations. Several examples have been worked out to illustrate the method.

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Analytical solutions are presented for the effectiveness factor of a zeroth-order reaction with volume change and nonuniform catalyst activity profile in slab, cylinder and spherical pellets. The possibility of shape normalization is considered for a variety of activity profiles and pellet shapes. When the catalyst activity at the external surface of the pellet is non-zero, shape normalization is obtained, which makes the asymptotic behavior of the effectiveness factor identical for small and large values of Thiele modulus, however, the normalization can lead to significant errors, particularly for the case of activity profiles decreasing towards the outer surface of the catalyst.

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As an art form, film has arguably always functioned as a stronghold for memory. Memories unfold in the stories told on screen, and remain preserved in the experiences of the audience viewing the film, at a particular time and place. The environment of a film festival further alters the viewing experience and its relationship to memory. The Brisbane International Film Festival (BIFF) was founded in 1992. After considerable disruption due to economic and socio-political changes, it took place for the last time in 2013. The change in BIFF’s leadership and programming agenda significantly impacted the festival’s image and its position on the wider festival circuit. Through an examination of cinema and memory) it will be argued that film festivals operate as (temporary) sites of memory, through the programming and screening of films, engagement with local audiences, and promotion of film culture. This specific and unique ‘festival memory’ inextricably links to the audience and the venue, and is curated by the festival programmers and staff, who carry a wealth of knowledge (not necessarily recorded), of past festivals, successes, and failures. The people involved, the festival staff and audience, act as caretakers of this ‘festival memory.’ This essay will therefore examine how the BIFF and its home, the Regent Theatre, have functioned as crucial ‘sites of memory’ for film and film culture in Brisbane, Australia.

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The rapid expansion of the international film festival circuit has included the loss of smaller, but well established festivals, often due to the perceived need for constant innovation and change. The Brisbane International Film Festival was founded in 1992. After considerable disruption to the festival’s leadership, programme and location due to economic and socio-political changes, it was held for the last time in 2013. Nafus and Anderson cite the term ‘lieux de memoire’, meaning ‘sites of memory’, as a place of “remembrance that exist(s) in a social world that constantly seeks to get ahead of itself, to “innovate” (Nafus and Anderson in Cefkin 2009, 141). The concept of ‘festival memory’ has not yet been explored in any depth, but such significant shifts in festivals such as BIFF are arguably sites where festival histories and identities, and film knowledge itself, can be irretrievably lost.

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This paper examines the idea that plasticity in farm management introduces resilience to change and allows farm businesses to perform when operating in highly variable environments. We also argue for the need to develop and apply more integrative assessments of farm performance that combine the use of modelling tools with deliberative processes involving farmers and researchers in a co-learning process, to more effectively identify and implement more productive and resilient farm businesses. In a plastic farming system, farm management is highly contingent on environmental conditions. In plastic farming systems farm managers constantly vary crops and inputs based on the availability of limited and variable resources (e.g. land, water, finances, labour, machinery, etc.), and signals from its operating environment (e.g. climate, markets), with the objective of maximising a number of, often competing, objectives (e.g. maximise profits, minimise risks, etc.). In contrast in more rigid farming systems farm management is more calendar driven and relatively fixed sequences of crops are regularly followed over time and across the farm. Here we describe the application of a whole farm simulation model to (i) compare, in silico, the sensitivity of two farming systems designs of contrasting levels of plasticity, operating in two contrasting environments, when exposed to a stressor in the form of climate change scenarios;(ii) investigate the presence of interactions and feedbacks at the field and farm levels capable of modifying the intensity and direction of the responses to climate signals; and (iii) discuss the need for the development and application of more integrative assessments in the analysis of impacts and adaptation options to climate change. In both environments, the more plastic farm management strategy had higher median profits and was less risky for the baseline and less intensive climate change scenarios (2030). However, for the more severe climate change scenarios (2070), the benefit of plastic strategies tended to disappear. These results suggest that, to a point, farming systems having higher levels of plasticity would enable farmers to more effectively respond to climate shifts, thus ensuring the economic viability of the farm business. Though, as the intensity of the stress increases (e.g. 2070 climate change scenario) more significant changes in the farming system might be required to adapt. We also found that in the case studies analysed here, most of the impacts from the climate change scenarios on farm profit and economic risk originated from important reductions in cropping intensity and changes in crop mix rather than from changes in the yields of individual crops. Changes in cropping intensity and crop mix were explained by the combination of reductions in the number of sowing opportunities around critical times in the cropping calendar, and to operational constraints at the whole farm level i.e. limited work capacity in an environment having fewer and more concentrated sowing opportunities. This indicates that indirect impacts from shifts in climate on farm operations can be more important than direct impacts from climate on the yield of individual crops. The results suggest that due to the complexity of farm businesses, impact assessments and opportunities for adaptation to climate change might also need to be pursued at higher integration levels than the crop or the field. We conclude that plasticity can be a desirable characteristic in farming systems operating in highly variable environments, and that integrated whole farm systems analyses of impacts and adaptation to climate change are required to identify important interactions between farm management decision rules, availability of resources, and farmer's preference.

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The availability and quality of irrigation water has become an issue limiting productivity in many Australian vegetable regions. Production is also under competitive pressure from supply chain forces. Producers look to new technologies, including changing irrigation infrastructure, exploring new water sources, and more complex irrigation management, to survive these stresses. Often there is little objective information investigating which improvements could improve outcomes for vegetable producers, and external communities (e.g. meeting NRM targets). This has led to investment in inappropriate technologies, and costly repetition of errors, as business independently discover the worth of technologies by personal experience. In our project, we investigated technology improvements for vegetable irrigation. Through engagement with industry and other researchers, we identified technologies most applicable to growers, particularly those that addressed priority issues. We developed analytical tools for ‘what if’ scenario testing of technologies. We conducted nine detailed experiments in the Lockyer Valley and Riverina vegetable growing districts, as well as case studies on grower properties in southern Queensland. We investigated root zone monitoring tools (FullStop™ wetting front detectors and Soil Solution Extraction Tubes - SSET), drip system layout, fertigation equipment, and altering planting arrangements. Our project team developed and validated models for broccoli, sweet corn, green beans and lettuce, and spreadsheets for evaluating economic risks associated with new technologies. We presented project outcomes at over 100 extension events, including irrigation showcases, conferences, field days, farm walks and workshops. The FullStops™ were excellent for monitoring root zone conditions (EC, nitrate levels), and managing irrigation with poor quality water. They were easier to interpret than the SSET. The SSET were simpler to install, but required wet soil to be reliable. SSET were an option for monitoring deeper soil zones, unsuitable for FullStop™ installations. Because these root zone tools require expertise, and are labour intensive, we recommend they be used to address specific problems, or as a periodic auditing strategy, not for routine monitoring. In our research, we routinely found high residual N in horticultural soils, with subsequently little crop yield response to additional nitrogen fertiliser. With improved irrigation efficiency (and less leaching), it may be timely to re-examine nitrogen budgets and recommendations for vegetable crops. Where the drip irrigation tube was located close to the crop row (i.e. within 5-8 cm), management of irrigation was easier. It improved nitrogen uptake, water use efficiency, and reduced the risk of poor crop performance through moisture stress, particularly in the early crop establishment phases. Close proximity of the drip tube to the crop row gives the producer more options for managing salty water, and more flexibility in taking risks with forecast rain. In many vegetable crops, proximate drip systems may not be cost-effective. The next best alternative is to push crop rows closer to the drip tube (leading to an asymmetric row structure). The vegetable crop models are good at predicting crop phenology (development stages, time to harvest), input use (water, fertiliser), environmental impacts (nutrient, salt movement) and total yields. The two immediate applications for the models are understanding/predicting/manipulating harvest dates and nitrogen movements in vegetable cropping systems. From the economic tools, the major influences on accumulated profit are price and yield. In doing ‘what if’ analyses, it is very important to be as accurate as possible in ascertaining what the assumed yield and price ranges are. In most vegetable production systems, lowering the required inputs (e.g. irrigation requirement, fertiliser requirement) is unlikely to have a major influence on accumulated profit. However, if a resource is constraining (e.g. available irrigation water), it is usually most profitable to maximise return per unit of that resource.

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Child care is a topic at the forefront of much discussion. From politicians to internet commentators, seemingly everyone has an opinion on child care in Australia at the moment. This media of late should have been an excellent opportunity to share information with parents and the wider community on the advances made in the early childhood profession through the National Quality Framework. It should have provided us with a strong platform to highlight the pedagogy and practice of educators choosing a career in early childhood...

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In a marketplace where millions of dollars are spent on the design of mobile games (m-games), social marketers are now using this technology as a tool for behaviour change. Despite high expenditure by governments and non-profits on social marketing m-games, little is known about their effectiveness in terms of creating value. Value creation has been demonstrated to have an important impact on satisfaction and behaviour. This paper reports the results of a qualitative study involving four focus groups with 23 participants to reveal two categories of experiential value, entertainment and behaviour. Additionally, it was discovered that entertainment could be characterised by amusement and social value dimensions. Whereas, behaviour could be made up of information, simulation and distraction value dimensions. The categories of value, as well as the dimensions of information, simulation and distraction are entirely new to the social marketing literature and thus represents a unique contribution to social marketing.

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We have all made these New Year’s resolutions before ... to be healthier, to eat better, to look after ourselves more, to go to the gym more. Each year, we are adamant we will stick with these resolutions, but deep down, we all know most of us will have given up before February even arrives. So we have put together a few tips to help you actively support your customers to make a significant lifestyle change for the New Year. Healthy eating – it is important for your customers to have realistic expectations. It is all too easy to say they will stop eating junk food, and start ‘eating healthy’. Advising them that it is important to be realistic and starting with a few small measurable goals, such as aiming to eat two servings of fruits or five servings of vegetables each day, will work better in the long run. Small tweaks and modifications can add up to a major change quite quickly...

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Many aquatic species are linked to environmental drivers such as temperature and salinity through processes such as spawning, recruitment and growth. Information is needed on how fished species may respond to altered environmental drivers under climate change so that adaptive management strategies can be developed. Barramundi (Lates calcarifer) is a highly prized species of the Indo-West Pacific, whose recruitment and growth is driven by river discharge. We developed a monthly age- and length-structured population model for barramundi. Monte Carlo Markov Chain simulations were used to explore the population's response to altered river discharges under modelled total licenced water abstraction and projected climate change, derived and downscaled from Global Climate Model A1FI. Mean values of exploitable biomass, annual catch, maximum sustainable yield and spawning stock size were significantly reduced under scenarios where river discharge was reduced; despite including uncertainty. These results suggest that the upstream use of water resources and climate change have potential to significantly reduce downstream barramundi stock sizes and harvests and may undermine the inherent resilience of estuarine-dependent fisheries. © 2012 CSIRO.

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- Problem Climate change is affecting the world in numerous ways such as increased temperatures, sea level rise, and increased droughts and floods. Governments worldwide, especially in the most vulnerable countries, are urged to seek better solutions for sustainable development. The construction industry and buildings have enormous impacts on humans and the environment, meaning green building must be one of the solutions. Government involvement is widely considered as one of the essential and most effective ways to promote green building and drive the construction market towards sustainability. This paper will review green building policy of the Pacific-Rim countries that are most vulnerable to climate change according to the recent Standard and Poor’s ranking, including: Cambodia, Vietnam, Fiji, Philippines, Papua New Guinea and Indonesia. Methodology: This paper will review policy related publications including journal and conference papers, portal websites of governments, legislation documents and reports of international organisations. It will focus on the policies and governmental instruments that support the adoption of green building practices. - Findings All six governments have launched climate change adaptation policies, showing a great concern regarding the damages caused by the phenomenon. All countries except Papua New Guinea have promulgated energy efficiency policy and programs which indirectly promote the adoption of green building practices. The comparison study shows that Philippines and Indonesia motivate the adoption of renewable energy generation, energy efficiency and green building through either financial or advocacy instruments, while other four countries tend to implement regulatory tools to mandate energy conservation. Through comparison, Cambodia and Vietnam – the two countries providing vision to develop green building - can learn from Philippines and Indonesia’s policy and instruments. - Research limitations Language differences between the countries and limit of formal sources may pose difficulties in searching for information. While much English language literature exists, sources from Cambodia, Philippines and Indonesia are less accessible. - Takeaway for practice As the paper provides more understanding about the supportive policy of those countries, it will introduce more opportunities for green property developers to invest in construction markets of those Pacific-Rim countries. - Originality There is little research reviewing green building supportive policies of developing and less-wealthy countries that are forecasted to be most vulnerable and most impacted by climate change. The originality of this paper lies in its investigation on how those countries intend to respond to this phenomenon and whether and to what extent they support the green building market by using policy tools.

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