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Increasing Needs and Solutions for Non-Baseload Operation of Nuclear Power Plants

Operation at steady full power, i.e. baseload operation, of nuclear power plants (NPPs) is usually considered to be the most efficient use of capital investment. Therefore, design and operation of most existing nuclear power plants (NPPs) are optimised to operate in baseload mode. Recently, there is an increasing need to operate NPPs in non-baseload mode, specifically performing frequency control and load following. These needs are typically due to a large nuclear generating capacity, increasing share of renewable generation, deregulation or evolution of the electricity supply systems and markets. Re-optimization of NPP design and operation for nonbaseload (flexible) mode of operation necessitates operational, economic and financial rearrangements to maintain the capital investment, in addition the adaptation of technical and regulatory changes. This paper discusses the aspects of design or operation of NPPs in flexible mode based on the existing knowledge and experience and it is primarily based on the recent study that was prepared by the International Atomic Energy Agency (IAEA)

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Stereospecific decarboylative allylation of sulfones

This document is the Accepted Manuscript version of a Published Work that appeared in final form in the Journal of the American Chemical Society, copyright © American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work see http://doi.org/10.1021/ja104196x.Allyl sulfonyl acetic esters undergo highly stereospecific, palladium-catalyzed decarboxylative allylation. The reaction allows the stereospecific formation of tertiary homoallylic sulfones in high yield. In contrast to related reactions that proceed at -100 °C and require highly basic preformed organometallics, the decarboxylative coupling described herein occurs under mild non-basic conditions and requires no stoichiometric additives. Allylation of the intermediate α-sulfonyl anion is more rapid than racemization, leading to a highly enantiospecific process. DFT calculations indicate that the barrier for racemization is 9.9 kcal/mol and thus the barrier of allylation must be <9.9 kcal/mol

Is resilience relevant to smoking abstinence for Indigenous Australians?

This article is under embargo for 12 months from the date of publication, in accordance with the publisher's policy. This is a pre-copyedited, author-produced PDF of an article accepted for publication in HEALTH PROMOTION INTERNATIONAL following peer review. The version of record [Tsourtos G, Ward P, Lawn S, Winefield A, Hersh D and Coveney J (2014) Is resilience relevant to smoking abstinence for Indigenous Australians? . Health Promotion International 30 (1): pp. 64-76] is available online at: http://heapro.oxfordjournals.org/content/30/1/64The prevalence rate of tobacco smoking remains high for Australian Indigenous people despite declining rates in other Australian populations. Given many Indigenous Australians continue to experience a range of social and economic structural problems, stress could be a significant contributing factor to preventing smoking abstinence. The reasons why some Indigenous people have remained resilient to stressful adverse conditions, and not rely on smoking to cope as a consequence, may provide important insights and lessons for health promotion policy and practice. In-depth interviews were employed to collect oral histories from 31 Indigenous adults who live in metropolitan Adelaide. Participants were recruited according to smoking status (non-smokers were compared to current smokers to gain a greater depth of understanding of how some participants have abstained from smoking). Perceived levels of stress were associated with encouraging smoking behaviour. Many participants reported having different stresses compared to non-Indigenous Australians, with some participants reporting having additional stressors such as constantly experiencing racism. Resilience often occurred when participants reported drawing upon internal psychological assets such as being motivated to quit and where external social support was available. These findings are discussed in relation to a recently developed psycho-social interactive model of resilience, and how this resilience model can be improved regarding the historical and cultural context of Indigenous Australians’ experience of smoking

Fast and flexible selection with a single switch

Selection methods that require only a single-switch input, such as a button click or blink, are potentially useful for individuals with motor impairments, mobile technology users, and individuals wishing to transmit information securely. We present a single-switch selection method, "Nomon," that is general and efficient. Existing single-switch selection methods require selectable options to be arranged in ways that limit potential applications. By contrast, traditional operating systems, web browsers, and free-form applications (such as drawing) place options at arbitrary points on the screen. Nomon, however, has the flexibility to select any point on a screen. Nomon adapts automatically to an individual's clicking ability; it allows a person who clicks precisely to make a selection quickly and allows a person who clicks imprecisely more time to make a selection without error. Nomon reaps gains in information rate by allowing the specification of beliefs (priors) about option selection probabilities and by avoiding tree-based selection schemes in favor of direct (posterior) inference. We have developed both a Nomon-based writing application and a drawing application. To evaluate Nomon's performance, we compared the writing application with a popular existing method for single-switch writing (row-column scanning). Novice users wrote 35% faster with the Nomon interface than with the scanning interface. An experienced user (author TB, with > 10 hours practice) wrote at speeds of 9.3 words per minute with Nomon, using 1.2 clicks per character and making no errors in the final text.Comment: 14 pages, 5 figures, 1 table, presented at NIPS 2009 Mini-symposi

Are there phylogenetic differences in salivary tannin-binding proteins between browsers and grazers, and ruminants and hindgut fermenters?

While feeding, mammalian browsers (primarily eat woody plants) encounter secondary metabolites such as tannins. Browsers may bind these tannins using salivary proteins, whereas mammalian grazers (primarily eat grasses that generally lack tannins) likely would not. Ruminant browsers rechew their food (ruminate) to increase the effectiveness of digestion, which may make them more effective at binding tannins than nonruminants. Few studies have included a sufficient number of species to consider possible scaling with body mass or phylogenetic effects on salivary proteins. Controlling for phylogeny, we ran inhibition radial diffusion assays of the saliva of 28 species of African herbivores that varied in size, feeding strategy, and digestive system. We could not detect the presence of salivary proline-rich proteins that bind tannins in any of these species. However, using the inhibition radial diffusion assay, we found considerable abilities to cope with tannins in all species, albeit to varying degrees. We found no differences between browsers and grazers in the effectiveness of their salivary proteins to bind to and precipitate tannins, nor between ruminants and nonruminants, or scaling with body mass. Three species bound all tannins, but their feeding niches included one browser (gray duiker), one mixed feeder (bush pig), and one grazer (red hartebeest). Five closely related species of small ruminant browsers were very effective in binding tannins. Megaherbivores, considered generalists on account of their large body size, were capable of binding tannins. However the grazing white rhinoceros was almost as effective at binding tannins as the megaherbivore browsers. We conclude, contrary to earlier predictions, that there were no differences in the relative salivary tannin-binding capability that was related to common ancestry (phylogeny) or to differences in body size.The National Research Foundation of South Africa, the Gay Langmuir Bursary from the University of KwaZulu-Natal and the Herrick Trust of Kent State University.http://www.ecolevol.orgam2020Mammal Research InstituteZoology and Entomolog