99 resultados para Leach, Michael


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Both prokaryotes and eukaryotes express a set of highly conserved proteins in response to external and internal stress. The stressors include tissue trauma,anoxia, heavy metal toxicity, infection, changed salinity, and the mmost characterized, heat shock. The result is an expression of stress proteins or heat shock proteins (HSP's) which lead to protection of protein integrity, and also to tolerance under continued heat stress conditions. The Australian backflip abalone (Haliotis rubra) is found principally in southern coastal water and also in estuarine/bay environments. Esturaine/bay environments have greater fluctuations in environmental conditions, especially those of salinity and water temperature, than they are found along oceanic coasts. Abalone from esturaine/bay and oceanic coastal environments were subjected to either increased temperature (2° C/day for a total of 10°C) or hyposalinity (80% seawater). Esturaine/bay abolone were less affectes than the oceanic animals by temperature increase and also demonstrated the ability to volume regualte 3 h after the initial salinity shock. SDS-PAGE and Western blotting techniques, together with dot blots of total protein, using HSP70 specific antibodies, were used to detect HSP70s in the foot muscle of the animals and indicated an expression of HSP70 in response to heat shock in abalone, but not following hyposalinity shock. RT-PCR yeilded a partial cDNA clone of HSP70 from the foot muscle.

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Michael Polanyi argues in Personal Knowledge (1958) that conceptual frameworks involved in major scientific controversies are separated by a `logical gap'. Such frameworks, according to Polanyi (1958: 151), are logically disconnected: their protagonists think differently, use different languages and occupy different worlds. Relinquishing one framework and adopting another, Polanyi's scientist undergoes a `conversion' to a new `faith'. Polanyi, in other words, presaged Kuhn and Feyerabend's concept of incommensurability. To what influences was Polanyi subject as he developed his concept of the logical gap? The answer, as unfolded in this article, is twofold: Evans-Pritchard's Witchcraft, Oracles and Magic among the Azande and the Confessions of St Augustine.

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The burning of brown coal for electricity generation produces thousands of tonnes of fly ash each year. Treatment of the fly ash can reduce leach rates of metals and allow it to be disposed in less prescribed landfill. A geopolymer matrix was investigated as a potential stabilisation method for fly ash obtained from electrostatic precipitators and ash disposal ponds. The ratio of fly ash and geopolymer was varied to determine the effects of different compositions on leaching rates. The major element leachate concentrations obtained from pond ash were lower than that of precipitator fly ash. Conversely, precipitator ash-geopolymers were better for trace heavy metal stabilisation. Effective reduction of elemental concentrations in the leachate has been achieved, particularly for calcium, arsenic, selenium, strontium and barium. Scanning electron microscopy revealed the distribution of metals originated from fly ash and from added geopolymer material. It also showed that some elements are leached from ash particles to the geopolymer phase and others remained as undissolved particles. Qualitative analysis showed that fly ash particles interacted with the geopolymers phase through surface reactions.

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The concentrations of 12 trace metals were assessed in wild and cultured specimens of blacklip abalone, Haliotis rubra, from each of two sites, Geelong and Port Fairy, in Victoria, Australia. Cadmium, copper, iron and zinc were quantified in the foot muscle of specimens from all four populations but the concentrations of aluminium, arsenic, beryllium, chromium, lead, manganese, nickel and vanadium were below the detection limits of the instrumental techniques employed. When similar sized specimens from each population were compared, the concentrations of each of the quantifiable metals varied according to location. The Geelong wild population had the highest or equal highest concentrations of each metal. Metal concentrations in the wild populations were usually greater than or equal to the concentrations in the corresponding cultured population. The concentrations of the regulated essential elements, copper and zinc, decreased with an increase in abalone length whereas the concentrations of iron, manganese and cadmium were independent of length. Metal concentrations in H. rubra from all sites complied with the Australian Food Code and other standards of food safety.


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The complete mitochondrial DNA of the blacklip abalone Haliotis rubra (Gastropoda: Mollusca) was cloned and 16,907 base pairs were sequenced. The sequence represents an estimated 99.85% of the mitochondrial genome, and contains 2 ribosomal RNA, 22 transfer RNA, and 13 protein-coding genes found in other metazoan mtDNA. An AT tandem repeat and a possible C-rich domain within the putative control region could not be fully sequenced. The H. rubra mtDNA gene order is novel for mollusks, separated from the black chiton Katharina tunicata by the individual translocations of 3 tRNAs. Compared with other mtDNA regions, sequences from the ATP8, NAD2, NAD4L, NAD6, and 12S rRNA genes, as well as the control region, are the most variable among representatives from Mollusca, Arthropoda, and Rhynchonelliformea, with similar mtDNA arrangements to H. rubra. These sequences are being evaluated as genetic markers within commercially important Haliotis species, and some applications and considerations for their use are discussed.

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The article argues that Polanyi was a likely source of influence on the theory of science that Kuhn developed in his The Structure of Scientific Revolutions (1962). The striking similarity between Kuhn’s idea of incommensurability and Polanyi’s rendering of scientific controversy in Personal Knowledge is featured here, and is used to expose a tension between Polanyi’s notions of scientific controversy and unfolding truth.

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In 1938, Joseph Oldham, a leading British Christian ecumenist, formed a discussion group that came to be known as the Moot. The Moot met in a retreat setting for several long weekends each year until early 1947, its discussions carefully organized and convened by Oldham. More than anything else, the discussions of the Moot revolved around the topic of order and, more particularly, around the problem of how order might be restored in British society and culture in the context of a ‘world turned upside down’. Oldham and most members of the group sought a central place for Christian ideas and ideals in British social life.

A striking feature of the Moot was the intellectual stature and the diversity of interests of its members. Among its 16 or so regular members were Oldham (1874-1969), his close friend T.S. Eliot (1888-1963) and Karl Mannheim (1893-1947). Among the later ‘visitors’ to Moot meetings was Michael Polanyi (1891-1976), who first came to the 20th Moot meeting in June of 1944.1

This article presents several papers that were produced for the Moot discussion of 15-18 December 1944 by Eliot, Mannheim and Polanyi. These papers have intrinsic and historical interest, and are published together for the first time here. The initial paper, written by Eliot, treats the role in society of ‘the clerisy’2 - a term borrowed from Samuel Taylor Coleridge that points to an intellectual elite or vanguard. Eliot requested that Oldham solicit responses to his paper from Mannheim and Polanyi. Mannheim’s response was a set of detailed answers to four questions that Eliot posed at the end of his essay. Polanyi’s response was a short, coherent essay, which he identified as ‘my own position with respect’ to Eliot’s discussion; his essay outlines a brief account of the role of the clerisy in science.3 Eliot wrote short comments on the responses of both Mannheim and Polanyi. These five pieces, which have a natural unity, should be of interest to anyone working in the history of social thought. We have abridged only Mannheim’s lengthy response and have eliminated a few lines of illustrative material from Eliot’s reply to Mannheim, but these excisions in no way detract from the clarity of the authors’ perspectives in this rich trilogue.

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This collection of essays demonstrates the continuing importance of the work of Michael Polanyi for the understanding, not only of the great events of the 20th century, but also of the problems that face us in the 21st century. Polanyi moved liberalism away from a negative, sceptical and rationalist basis towards an acceptance of trust, tradition and faith in transcendent values. His conception of the free society is not one merely of doing as one pleases nor vacuously 'open', but one of individual and communal self-dedication to those values and ideals.These essays, authored by a distinguished international and interdisciplinary panel of invited contributors, examine Polanyi's specific insights in the theory of knowledge, the nature and source of social order and the philosophy of economics and science and draw relevant comparisons between Polanyi and related thinkers such as Popper, Hayek and Mises. This book shows the sources of Polanyi's ideas and his distinctive contribution to philosophy generally, to social and political thought and to economics.

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This essay reviews historical records that set forth the discussions and interaction of Michael Polanyi and Karl Mannheim from 1944 until  Mannheim’s death early in 1947. The letters describe Polanyi’s effort to assemble a book to be published in a series edited by Manneheim. They  also reveal the different perspectives these thinkers took about freedom and the historical context of ideas. Records of J.H. Oldham’s discussion group “the Moot” suggest that these and other differences in philosophy were  debated in meetings of “the Moot” attended by Polanyi and Mannheim in 1944.

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The screening of Martin Bashir's Living with Michael Jackson on Australian television elicited a phenomenal amount of interest in the news media, at water coolers and on the Internet. Much of the response in the Australian print media was critical of Bashir's representation of Jackson, as well as denouncing Jackson as sad victim, warped predator and allround freakshow. This article considers these interpretations to argue that the production and consumption of 'wacko Jacko' is underpinned by the increasing instability of the natural in an age of information technologies, as well as the collapse of boundaries between documentary and fictional entertainment forms.