121 resultados para ESR dating
Resumo:
This chapter surveys the landscape of mobile dating and hookup apps—understood as media technologies, as businesses, and as sites of social practice. It situates the discussion within the broader contexts of technologically mediated dating and digital sexual cultures. By outlining a number of methodological approaches and data sources that can be used in the study of dating and hookup apps, it equips the reader with tools and approaches for investigating hookup app culture in ways that go beyond “media panics” – the familiar combination of moral panics and media effects which is so prevalent in discussions of sexuality in digital media.
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In modern evolutionary divergence analysis the role of geological information extends beyond providing a timescale, to informing molecular rate variation across the tree. Here I consider the implications of this development. I use fossil calibrations to test the accuracy of models of molecular rate evolution for placental mammals, and reveal substantial misspecification associated with life history rate correlates. Adding further calibrations to reduce dating errors at specific nodes unfortunately tends to transfer underlying rate errors to adjacent branches. Thus, tight calibration across the tree is vital to buffer against rate model errors. I argue that this must include allowing maximum bounds to be tight when good fossil records permit, otherwise divergences deep in the tree will tend to be inflated by the interaction of rate errors and asymmetric confidence in minimum and maximum bounds. In the case of placental mammals I sought to reduce the potential for transferring calibration and rate model errors across the tree by focusing on well-supported calibrations with appropriately conservative maximum bounds. The resulting divergence estimates are younger than others published recently, and provide the long-anticipated molecular signature for the placental mammal radiation observed in the fossil record near the 66 Ma Cretaceous–Paleogene extinction event.
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Raman spectroscopic analyses of fragmented wall-painting specimens from a Romano-British villa dating from ca. 200 AD are reported. The predominant pigment is red haematite, to which carbon, chalk and sand have been added to produce colour variations, applied to a typical Roman limewash putty composition. Other pigment colours are identified as white chalk, yellow (goethite), grey (soot/chalk mixture) and violet. The latter pigment is ascribed to caput mortuum, a rare form of haematite, to which kaolinite (possibly from Cornwall) has been added, presumably in an effort to increase the adhesive properties of the pigment to the substratum. This is the first time that kaolinite has been reported in this context and could indicate the successful application of an ancient technology discovered by the Romano-British artists. Supporting evidence for the Raman data is provided by X-ray diffraction and SEM-EDAX analyses of the purple pigment.
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The Architecture, Disciplinarity and the Arts symposium was organised by the Architecture. Theory, Criticism and History (ATCH) research group at the University of Queensland, run by John Macarthur and Antony Moulis, together with Andrew Leach who joined them last year and organised much of the symposium. The symposium ran for three days in a small room at the Institute of Modern Art (IMA) in Fortitude Valley, Brisbane (generously donated by director Robert Leonard), with about 40 people in attendance. Together with a long question time of an hour after every three speakers, the size of the room and the small number of people made it very different from most architecture or design conferences. The intellectual level of the symposium was high, without the speed dating aspect that one often sees at the Society of Architectural Historians, Australia and New Zealand (SAHANZ) meetings, where endless parallel sessions of short papers create an occasionally disorientating cacophony of words. The symposium was deliberately, unapologetically academic and the intimate nature of the forum made the discussion rich and collaborative, with an active audience. The title of the symposium, 'Architecture, Disciplinarity and the Arts', reflects the connection that already exists between the art history and the architectural history community in Brisbane, with both groups regularly attending each other's functions.
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Live-collected samples of four common reef building coral genera (Acropora, Pocillopora, Goniastrea, Porites) from subtidal and intertidal settings of Heron Reef, Great Barrier Reef, show extensive early marine diagenesis where parts of the coralla less than 3 years old contain abundant macro- and microborings and aragonite, high-Mg calcite, low-Mg calcite, and brucite cements. Many types of cement are associated directly with microendoliths and endobionts that inhabit parts of the corallum recently abandoned by coral polyps. The occurrence of cements that generally do not precipitate in normal shallow seawater (e.g., brucite, low-Mg calcite) highlights the importance of microenvironments in coral diagenesis. Cements precipitated in microenvironments may not reXect ambient seawater chemistry. Hence, geochemical sampling of these cements will contaminate trace-element and stable-isotope inventories used for palaeoclimate and dating analysis. Thus, great care must be taken in vetting samples for both bulk and microanalysis of geochemistry. Visual inspection using scanning electron microscopy may be required for vetting in many cases.
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Raman spectroscopy and FT-IR imaging analyses of cave wall pigment samples from north Queensland (Australia) indicate that some hand stencils were undertaken during a dry environmental phase indicating late Holocene age. Other, earlier painting episodes also took place during dry environmental periods of the terminal Pleistocene and/or early Holocene. These results represent a rare opportunity to attain chronological information for rock art in conditions where insufficient carbon is present for radiocarbon dating.
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This thesis is a study of naturally occurring radioactive materials (NORM) activity concentration, gamma dose rate and radon (222Rn) exhalation from the waste streams of large-scale onshore petroleum operations. Types of activities covered included; sludge recovery from separation tanks, sludge farming, NORM storage, scaling in oil tubulars, scaling in gas production and sedimentation in produced water evaporation ponds. Field work was conducted in the arid desert terrain of an operational oil exploration and production region in the Sultanate of Oman. The main radionuclides found were 226Ra and 210Pb (238U - series), 228Ra and 228Th (232Th - series), and 227Ac (235U - series), along with 40K. All activity concentrations were higher than the ambient soil level and varied over several orders of magnitude. The range of gamma dose rates at a 1 m height above ground for the farm treated sludge had a range of 0.06 0.43 µSv h 1, and an average close to the ambient soil mean of 0.086 ± 0.014 µSv h 1, whereas the untreated sludge gamma dose rates had a range of 0.07 1.78 µSv h 1, and a mean of 0.456 ± 0.303 µSv h 1. The geometric mean of ambient soil 222Rn exhalation rate for area surrounding the sludge was mBq m 2 s 1. Radon exhalation rates reported in oil waste products were all higher than the ambient soil value and varied over three orders of magnitude. This study resulted in some unique findings including: (i) detection of radiotoxic 227Ac in the oil scales and sludge, (ii) need of a new empirical relation between petroleum sludge activity concentrations and gamma dose rates, and (iii) assessment of exhalation of 222Rn from oil sludge. Additionally the study investigated a method to determine oil scale and sludge age by the use of inherent behaviour of radionuclides as 228Ra:226Ra and 228Th:228Ra activity ratios.
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How interactive new media art can effectively communicate an indigenous philosophical concept. The sophistication and complexity of the philosophical concept concerning relationships between land and people and between people, intrinsic to the laws and customs of Australian Indigenous society, has begun to be communicated and accessed beyond the realm of anthropological and ethnological domains of Western scholarship. The exciting scope and rapid development of new media arts presents an innovative means of creating an interactive relationship with the general Australian public, addressing the urgent need for an understanding of Indigenous Australian concepts of relationship to land, and to each other, absent from Western narratives. The study is framed by an Indigenous concept of place, and relationships between land and people and between people; and explores how this concept can be clearly communicated through interactive new media arts. It involves: a creative project, the development of an interactive new media art project, a website work-in-progress titled site\sight\cite; and an exegesis, a Novella of Ideas, on the origins, influences, objectives, and potential of creative practices and processes engaged in the creative project. Research undertaken for the creative project and exegesis extended my creative practice into the use of interdisciplinary arts, expressly for the expression of philosophical concepts, consolidating 23 years experience in Indigenous community arts development. The creative project and exegesis contributes to an existing body of Indigenous work in a range of areas - including education, the arts and humanities - which bridges old and new society in Australia. In this study, old and new society is defined by the time of the initial production of art and foundations of knowledge, in the country of its origins, in Indigenous Australia dating back at least 40,000 years.
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Hamilton (2001) makes a number of comments on our paper (Harding and Pagan, 2002b). The objectives of this rejoinder are, firstly, to note the areas in which we agree; secondly, to define with greater clarity the areas in which we disagree; and, thirdly, to point to other papers, including a longer version of this response, where we have dealt with some of the issues that he raises. The core of our debate with him is whether one should use an algorithm with a specified set of rules for determining the turning points in economic activity or whether one should use a parametric model that features latent states. Hamilton begins his criticism by stating that there is a philosophical distinction between the two methods for dating cycles and concludes that the method we use “leaves vague and intuitive exactly what this algorithm is intended to measure”. Nothing is further from the truth. When seeking ways to decide on whether a turning point has occurred it is always useful to ask the question, what is a recession? Common usage suggests that it is a decline in the level of economic activity that lasts for some time. For this reason it has become standard to describe a recession as a decline in GDP that lasts for more than two quarters. Finding periods in which quarterly GDP declined for two periods is exactly what our approach does. What is vague about this?
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Shakespeare’s Ophelia has been circulated in recent times as a figure of the adolescent woman at risk. Mary Pipher’s best-selling and influential Reviving Ophelia (1994) argued that the “story of Ophelia […] shows the destructive forces that affect young women” (20). Without undermining Pipher’s project, this paper reads two contemporary YA romance novels—Lisa Fiedler’s Dating Hamlet (2002) and Lisa Klein’s Ophelia (2006)—in order to demonstrate that not only can Ophelia be appropriated as a figure of empowerment for young women today, but that such appropriations are, seemingly ironically, most powerfully rendered within the genre of romance; a genre long-maligned by feminists as recuperative of patriarchy.--------- These two novels stage interventions both into narratives of female adolescence as a time of being ‘at risk’ or ‘under threat’, and also into narratives of canonical literary patriarchy. Rather than a suicidal Ophelia, subject to the whims of men, these authors imagine Ophelias who take charge of their own destiny; who dictate their own romance and agency; who refuse to be subject to or subjected by, those scripts of cultural authority and heteronormative romance so often perceived as antithetical to female agency. In doing so, they force us to revise our own notions of the romance genre and the functions of canonical literary tradition in contemporary YA culture.
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Our understanding of how the environment can impact human health has evolved and expanded over the centuries, with concern and interest dating back to ancient times. For example, over 4000 years ago, a civilisation in northern India tried to protect the health of its citizens by constructing and positioning buildings according to strict building laws, by having bathrooms and drains, and by having paved streets with a sewerage system (Rosen 1993). In more recent times, the ‘industrial revolution’ played a dominant role in shaping the modern world, and with it the modern public health system. This era was signified by rapid progress in technology, the growth of transportation and the expansion of the market economy, which lead to the organisation of industry into a factory system. This meant that labour had to be brought to the factories and by the 1820s, poverty and social distress (including overcrowding and infrequent sewage and garbage disposal) was more widespread than ever. These circumstances, therefore, lead to the rise of the ‘sanitary revolution’ and the birth of modern public health (Rosen 1993). The sanitary revolution has also been described as constituting the beginning of the first wave of environmental concern, which continued until after World War 2 when major advances in engineering and chemistry substantially changed the face of industry, particularly the chemical sector. The second wave of environmental concern came in the mid to late 20th century and was dominated by the environmental or ecology movement. A landmark in this era was the 1962 publication of the book Silent Spring by Rachel Carson. This identified for the first time the dramatic effects on the ecosystem of the widespread use of the organochlorine pesticide, DDT. The third wave of environmental concern commenced in the 1980s and continues today. The accelerated rate of economic development, the substantial increase in the world population and the globalisation of trade have dramatically changed the production methods and demand for goods in both developed and developing countries. This has lead to the rise of ‘sustainable development’ as a key driver in environmental planning and economic development (Yassi et al 2001). The protection of health has, therefore, been a hallmark of human history and is the cornerstone of public health practice. This chapter introduces environmental health and how it is managed in Australia, including a discussion of the key generic management tools. A number of significant environmental health issues and how they are specifically managed are then discussed, and the chapter concludes by discussing sustainable development and its links with environmental health.