456 resultados para powerful owl


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This paper examines how creativity and the arts can assist teachers who teach from a social justice perspective, and how knowledge built through meaningful experiences of difference can make a difference. Just as imagining is central to visual arts practice, so too the capacity to imagine is a necessity for social justice. The authors ask what art can do, and how art can work, to bring about greater understandings and practices around social justice and the early years. A ‘recognitive justice’ (Fraser, 1997, 2000; Cazden, 2012) requires the capacity to be sensitive to the multiple voices that need to be heard, and the ability to imagine how lives might be lived differently. The arts can provide powerful means for thinking social justice, and the experiences described in this paper can have application in addressing social justice in the professional preparation of prospective teachers. Three teacher educators who teach from a social justice perspective apply a collective biography methodology to their stories of art activity. Data were collected from three sites: transcripts, notes and digital images from a salon evening; ethnographic observations, field notes and artefacts from a school classroom; and a/r/tographic data generated in a university art classroom. Data were analysed using Foucault and the conceptual work of other post-structuralist philosophies, to explore how aesthetic and creative artistic activity could excite imaginations and open up multiple possibilities for richer forms of educational outcomes – for teacher educators, their students, and ultimately for young children.

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Despite the dominancy of medical explanations for difficult child behavior, the shifting sands that lie beneath the ADHD construct provide an unstable foundation for educational practice. It can be somewhat liberating to remember that “attention deficit hyperactivity disorder” is a label (one of many, including minimal brain damage and hyperkinetic reaction of childhood) that the medical domain has coined to both group and describe certain challenging behaviors exhibited by children and young people (see Smith, Chapter 2). The label is but one conceptualization of what these behaviors mean and, despite the existence of powerful lobby groups, it may not be the best way forward. In what follows, I present an alternative typology to the medical conceptualization by describing some common issues that bring this group of children to attention. In an effort to introduce educationally useful responses to students who are difficult to teach, I will then outline what classroom teachers need to recognize in order to work with these students and realize their potential. To assist teachers in thinking pedagogically, these observations are coupled with well-known and relevant qualities of good teaching to remind teachers of what they already know and to reacquaint them with the power of that knowledge.

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Radical-directed dissociation of gas phase ions is emerging as a powerful and complementary alternative to traditional tandem mass spectrometric techniques for biomolecular structural analysis. Previous studies have identified that coupling of 2-[(2,2,6,6-tetramethylpiperidin-1-oxyl)methyl] benzoic acid (TEMPO-Bz) to the N-terminus of a peptide introduces a labile oxygen-carbon bond that can be selectively activated upon collisional activation to produce a radical ion. Here we demonstrate that structurally-defined peptide radical ions can also be generated upon UV laser photodissociation of the same TEMPO-Bz derivatives in a linear ion-trap mass spectrometer. When subjected to further mass spectrometric analyses, the radical ions formed by a single laser pulse undergo identical dissociations as those formed by collisional activation of the same precursor ion, and can thus be used to derive molecular structure. Mapping the initial radical formation process as a function of photon energy by photodissociation action spectroscopy reveals that photoproduct formation is selective but occurs only in modest yield across the wavelength range (300-220 nm), with the photoproduct yield maximised between 235 and 225 nm. Based on the analysis of a set of model compounds, structural modifications to the TEMPO-Bz derivative are suggested to optimise radical photoproduct yield. Future development of such probes offers the advantage of increased sensitivity and selectivity for radical-directed dissociation. © 2014 the Owner Societies.

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We introduce the notion of distributed password-based public-key cryptography, where a virtual high-entropy private key is implicitly defined as a concatenation of low-entropy passwords held in separate locations. The users can jointly perform private-key operations by exchanging messages over an arbitrary channel, based on their respective passwords, without ever sharing their passwords or reconstituting the key. Focusing on the case of ElGamal encryption as an example, we start by formally defining ideal functionalities for distributed public-key generation and virtual private-key computation in the UC model. We then construct efficient protocols that securely realize them in either the RO model (for efficiency) or the CRS model (for elegance). We conclude by showing that our distributed protocols generalize to a broad class of “discrete-log”-based public-key cryptosystems, which notably includes identity-based encryption. This opens the door to a powerful extension of IBE with a virtual PKG made of a group of people, each one memorizing a small portion of the master key.

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In this work, we propose a new generalization of the notion of group signatures, that allows signers to cover the entire spectrum from complete disclosure to complete anonymity. Previous group signature constructions did not provide any disclosure capability, or at best a very limited one (such as subset membership). Our scheme offers a very powerful language for disclosing exactly in what capacity a subgroup of signers is making a signature on behalf of the group.

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The cryptographic community has, of late, shown much inventiveness in the creation of powerful new IBE-like primitives that go beyond the basic IBE notion and extend it in many new directions. Virtually all of these “super-IBE” schemes rely on bilinear pairings for their implementation, which they tend to use in a surprisingly small number of different ways: three of them as of this writing. What is interesting is that, among the three main frameworks that we know of so far, one has acted as a veritable magnet for the construction of many of these “generalized IBE” primitives, whereas the other two have not been nearly as fruitful in that respect. This refers to the Commutative Blinding framework defined by the Boneh-Boyen [Bscr ][Bscr ]1 IBE scheme from 2004. The aim of this chapter is to try to shed some light on this approach's popularity, first by comparing its key properties with those of the competing frameworks, and then by providing a number of examples that illustrate how those properties have been used.

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The present paper explores extreme car audio systems and the culture and practices that surround car audio competitions. I begin by examining whether, and how, car audio can be thought of as a 'music scene' and in what ways the culture and practice of car audio may fit within post-subcultural discourses. Following this, I offer a description of car audio competitions, revealing some of the practices that define this aspect of car audio scenes. In particular, I concentrate on sound pressure level (SPL) competitions and some of the interesting aspects of the SPL scene. Finally, I briefly examine how the powerful effects (and affects) of bass frequencies are an important part of the attraction of loud car audio systems and how car audio systems contribute to the territorializing of urban spaces.

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Fibroblast growth factor-2 (FGF2) is a powerful promoter of bone growth. We demonstrate here that brief exposure to FGF2 enhances mineralized nodule formation in cultured rat osteoprogenitor cells due to an expansion of cells that subsequently mineralize. This mitogenic effect is mediated via sulfated glycosaminoglycans (GAGs), FGFR1, and the extracellular signal-regulated kinase (ERK) pathway. The GAGs involved in this stimulation are chondroitin sulfates (CS) rather than heparan sulfates (HS). However, continuous FGF2 treatment reduces alkaline phosphatase (ALP) activity, downregulates collagen Ialpha1 (ColIalpha1) and FGFR3 expression, upregulates the expression and secretion of osteopontin (OPN) and inhibits mineralization. The inhibitory effects of FGF2 on FGFR3 expression and ALP activity are also mediated by the ERK pathway, although the effects of FGF2 on ColIalpha1 and OPN expression are mediated by GAGs and PKC activity. Thus short-term activation of FGF2/FGFR1 promotes osteoprogenitor proliferation and subsequent differentiation, while long-term activation of FGF2 signaling disrupts mineralization by modulating osteogenic marker expression. This study thus establishes the central role of sulfated GAGs in the osteogenic progression of osteoprogenitors.

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Body and Forgetting is a powerful dance performance that brings together the work of choreographer Liz Roche and film maker Alan Gilsenan, with a live score by Denis Roche. Inspired by the writings of Milan Kundera, Liz Roche Company's remarkable dancers find their way through delicately woven circumstances of disappearance, loss, relationship and hope. Their attempts to hold fast to memories and objects of meaning is at the heart of this work. The live performers move in dialogue with filmed versions of their dancing selves. They re-write their histories, make better endings to their stories, say what they regret not having said. These filmed reflections or versions of themselves, by offering a mirror, ultimately bring the performers back to themselves, richer from the experience.

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Of all the stories to emerge from Queensland’s catastrophic summer of 2011, the most dramatic and starkly tragic were those that took place in Toowoomba and the Lockyer Valley. On January 10, 2011, after weeks of heavy rain and as floodwaters began to overwhelm much of south-east Queensland, an ‘inland tsunami’ hit the city of Toowoomba, the rural districts of Spring Bluff and Postmans Ridge, and the towns of Murphys Creek, Withcott, Helidon, and Grantham. The Torrent:Toowoomba and the Lockyer Valley, 10 January 2011 tells, for the first time, the extraordinary stories of survival and loss that emerged from that terrible day. Official figures state that twenty-four people died. Many escaped death only because they were rescued by members of the community or through sheer good fortune. Based on exclusive interviews with survivors, rescuers and with the families and friends of victims of the disaster, The Torrent is a unique and powerful account of human courage in the face of the devastating force of nature, and the enduring resilience of ordinary Australians.

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Nick Shackleton’s research on piston cores from the Iberian margin highlighted the importance of this region for providing high-fidelity records of millennial-scale climate variability, and for correlating climate events from the marine environment to polar ice cores and European terrestrial sequences. During the Integrated Ocean Drilling Program (IODP) Expedition 339, we sought to extend the Iberian margin sediment record by drilling with the D/V JOIDES Resolution. Five holes were cored at Site U1385 using the advanced piston corer (APC) system to a maximum depth of ∼ 155.9 m below sea floor (m b.s.f.). Immediately after the expedition, cores from all holes were analyzed by core scanning X-ray fluorescence (XRF) at 1 cm spatial resolution. Ca/Ti data were used to accurately correlate from hole-to-hole and construct a composite spliced section, containing no gaps or disturbed intervals to 166.5 m composite depth (mcd). A low-resolution (20 cm sample spacing) oxygen isotope record confirms that Site U1385 contains a continuous record of hemipelagic sedimentation from the Holocene to 1.43 Ma (Marine Isotope Stage 46). The sediment profile at Site U1385 extends across the middle Pleistocene transition (MPT) with sedimentation rates averaging ∼ 10 cm kyr−1. Strongprecession cycles in colour and elemental XRF signals provide a powerful tool for developing an orbitally tuned reference timescale. Site U1385 is likely to become an important type section for marine–ice–terrestrial core correlations and the study of orbital- and millennial-scale climate variability.

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Pyrido[1,2-a]benzimidazoles1, 2a are interesting compounds both from the viewpoint of medicinal chemistry2–7 (solubility,7 DNA intercalation3) and materials chemistry8 (fluorescence). Of note among the former is the antibiotic drug Rifaximin,5 which contains this heteroaromatic core. The classical synthetic approach for the assembly of pyrido[1,2-a]benzimidazoles is by [3+3] cyclocondensation of benzimidazoles containing a methylene group at C2 with appropriate bielectrophiles.2a However, these procedures are often low-yielding, involve indirect/lengthy sequences, and/or provide access to a limited range of products, primarily providing derivatives with substituents located on the pyridine ring (A ring, Scheme 1).2–4 Theoretically, a good alternative synthetic method for the synthesis of pyrido[1,2-a]benzimidazoles with substituents in the benzene ring (C ring) should be accessible by intramolecular transition-metal-catalyzed CN bond formation in N-(2-chloroaryl)pyridin-2-amines, based on chemistry recently developed in our research group.9 These substrates themselves are easily available through SNAr or selective Pd-catalyzed amination10 of 2-chloropyridine with 2-chloroanilines.11 If a synthetic procedure that eliminated the need for preactivation of the 2-position of the 2-chloroarylamino entity could be developed, this would be even more powerful, as anilines are more readily commercially available than 2-chloroanilines. Therefore the synthesis of pyrido[1,2-a]benzimidazoles (4) by a transition-metal-catalyzed intramolecular CH amination approach from N-arylpyridin-2-amines (3) was explored (Scheme 1).

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The most widely used introduction to the Australian media, fully updated to reflect the increasing prominence of the internet in the communication and entertainment industries. Description Traditional media are being reshaped by digital technologies. The funding model for quality journalism has been undermined by the drift of advertising online, demarcations between different forms of media are rapidly fading, and audiences have fragmented. We can catch up with our favourite TV show on a tablet, social media can be more important than mainstream radio in a crisis, and organisations large and small have become publishers in their own right on apps. Nevertheless mainstream media remain powerful. The Media and Communications in Australia offers a systematic introduction to this dynamic field. Fully updated and revised to take account of recent developments, this fourth edition outlines the key media industries and explains how communications technologies are impacting on them. It provides a thorough overview of the main approaches taken in studying the media, and includes an expanded 'issues' section with new chapters on social media, gaming, apps, the environment, media regulation, ethics and privacy. With contributions from some of Australia's best researchers and teachers in the field, The Media and Communications in Australia remains the most comprehensive and reliable introduction to media and communications available. It is an ideal student text, and a reference for teachers of media and anyone interested in this influential industry.

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Regulation has played a significant role in shaping the financial services sector in Australia over the past few decades. Regulatory changes have included the establishment of the Australian Prudential Regulation Authority (APRA), floating the Australian dollar, allowing foreign financial institutions to operate domestically, the introduction of the superannuation guarantee charge, and the removal of interest rate controls. As the economy emerges from the worst financial crisis since the great depression, a new force of change that is recognised as one of the most significant sources of risk and opportunity facing the business community in the foreseeable future is that of climate change. Climate change is expected to be a significant change agent in the financial services sector as extreme weather patterns, sea level rises, and atmospheric changes impact on asset values (both investment and lending), project finance, and risk products. The financial services industry will be particularly affected by these developments, both as a provider of financial products (capital, credit, investment, advice, and insurance), and also through its powerful influence on the economy in terms of capital allocation. In addition, industry constituents will be heavily impacted by government regulation in this area (reporting, emissions trading and environmental policies), with respect to their own business practices and also those of their clients. This study reports the results of interviews conducted with senior members of the finance sector working in the sustainability area to gauge their perceptions of the challenges facing the sector with respect to climate change. Our results confirm that that regulatory intervention will be critical to climate change response gaining traction and momentum. In particular, regulatory certainty will promote engagement, particularly in relation to the Carbon Pollution Reduction Scheme (CPRS), with other developments needed in terms of information disclosure, performance and remuneration, and incentive programs. Accordingly, the significant potential risks and opportunities that climate change presents to the sector, and the broader economy, will in part be managed/realised only if a swift and significant regulatory response is achieved.

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Contemporary lipidomics protocols are dependent on conventional tandem mass spectrometry for lipid identification. This approach is extremely powerful for determining lipid class and identifying the number of carbons and the degree of unsaturation of any acyl-chain substituents. Such analyses are however, blind to isomeric variants arising from different carbon carbon bonding motifs within these chains including double bond position, chain branching, and cyclic structures. This limitation arises from the fact that conventional, low energy collision-induced dissociation of even-electron lipid ions does not give rise to product ions from intrachain fragmentation of the fatty acyl moieties. To overcome this limitation, we have applied radical-directed dissociation (RDD) to the study of lipids for the first time. In this approach, bifunctional molecules that contain a photocaged radical initiator and a lipid-adducting group, such as 4-iodoaniline and 4-iodobenzoic acid, are used to form noncovalent complexes (i.e., adduct ions) with a lipid during electrospray ionization. Laser irradiation of these complexes at UV wavelengths (266 nm) cleaves the carbon iodine bond to liberate a highly reactive phenyl radical. Subsequent activation of the nascent radical ions results in RDD with significant intrachain fragmentation of acyl moieties. This approach provides diagnostic fragments that are associated with the double bond position and the positions of chain branching in glycerophospholipids, sphingomyelins and triacylglycerols and thus can be used to differentiate isomeric lipids differing only in such motifs. RDD is demonstrated for well-defined lipid standards and also reveals lipid structural diversity in olive oil and human very-low density lipoprotein.