29,450 research outputs found

    Darwin endures, despite disparagement

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    Evolution lies at the heart of the life sciences, and Charles Darwin is a towering historical figure within evolutionary science. One testimony to his lasting influence is that declaring Darwin to have been wrong all along remains a provocative way to command attention. The present paper discusses various strands of β€œDarwin was wrong” partisans and their divergent views and motives: some are looking to Darwin to justify or condemn the political ideologies that they support or reject; others are concerned with the corrupting influence that the bleak cosmic outlook of evolution is deemed to exert on the moral or religious rectitude of impressionable minds, or regard Darwinism as a direct assault on religion; philosophers question the very coherence of the entire enterprise; and certain biologists aspire to go down in history as even greater than Darwin. It is sobering to reflect that this diverse group is united only by their poor grasp of Darwin’s theory of natural selection

    Arachidonic Acid as a Possible Negative Feedback Inhibitor of Nicotinic Acetylcholine Receptors on Neurons

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    Neuronal acetylcholine receptors, being highly permeable to calcium, are likely to regulate calcium-dependent events in neurons. Arachidonic acid is a membrane-permeant second messenger that can be released from membrane phospholipids by phospholipases in a calcium-dependent manner. We show here that activation of neuronal acetylcholine receptors triggers release of 3H-arachidonic acid in a calcium-dependent manner from neurons preloaded with the fatty acid. Moreover, low concentrations of arachidonic acid reversibly inhibit the receptors and act most efficiently on receptors likely to have the highest permeability to calcium, namely receptors containing Ξ±7 subunits. Low concentrations of arachidonic acid also reversibly inhibit Ξ±7- containing receptors expressed in Xenopus oocytes following injection of Ξ±7 cRNA. The oocyte results indicate following injection of Ξ±7 cRNA. The oocyte results indicate that the inhibition is a feature of the receptors rather than a consequence of neuron-specific machinery. The inhibition is not mediated by specific metabolites of arachidonic acid because the effects can be mimicked by other fatty acids; their effectiveness correlates with their content of double bonds. In contrast to arachidonic effects on calcium currents, inhibition of neuronal nicotinic receptors by the fatty acid cannot be prevented by blocking production of free radicals or by inhibiting protein kinase C. An alternative mechanism is that arachidonic acid binds directly to the receptors or perturbs the local environment in such a manner as to constrain receptor function

    Totalitarianism and geography: L.S. Berg and the defence of an academic discipline in the age of Stalin

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    In considering the complex relationship between science and politics, the article focuses upon the career of the eminent Russian scholar, Lev Semenovich Berg (1876–1950), one of the leading geographers of the Stalin period. Already before the Russian Revolution, Berg had developed a naturalistic notion of landscape geography which later appeared to contradict some aspects of Marxist–Leninist ideology. Based partly upon Berg's personal archive, the article discusses the effects of the 1917 revolution, the radical changes which Stalin's cultural revolution (from the late 1920s) brought upon Soviet science, and the attacks made upon Berg and his concept of landscape geography thereafter. The ways in which Berg managed to defend his notion of geography (sometimes in surprisingly bold ways) are considered. It is argued that geography's position under Stalin was different from that of certain other disciplines in that its ideological disputes may have been regarded as of little significance by the party leaders, certainly by comparison with its practical importance, thus providing a degree of β€˜freedom’ for some geographers at least analogous to that which has been described by Weiner (1999. A little corner of freedom: Russian nature protection from Stalin to Gorbachev. Berkeley: University of California Press) for conservationists. It is concluded that Berg and others successfully upheld a concept of scientific integrity and limited autonomy even under Stalinism, and that, in an era of β€˜Big Science’, no modernizing state could or can afford to emasculate these things entirely

    Generation of Whole-Body Expressive Movement Based on Somatical Theories

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    An automatic choreography method to generate lifelike body movements is proposed. This method is based on somatics theories that are conventionally used to evaluate human’s psychological and developmental states by analyzing the body movement. The idea of this paper is to use the theories in the inverse way: to facilitate generation of artificial body movements that are plausible regarding evolutionary, developmental and emotional states of robots or other non-living movers. This paper reviews somatic theories and describes a strategy for implementations of automatic body movement generation. In addition, a psychological experiment is reported to verify expression ability on body movement rhythm. This method facilitates to choreographing body movement of humanoids, animal-shaped robots, and computer graphics characters in video games

    Cultural matter in the development of an interactive multimedia self-paced educational health program for aboriginal health workers

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    Aboriginal and Torres Strait islander health workers are key providers of primary health services to Aboriginal communities especially in remote and rural areas. They are often overloaded with competing demands. There has been limited attention given to the maintenance and ongoing enhancement of their skills and knowledge following the completion of formal training. A culturally appropriated interactive multimedia self-paced health program as a mechanism to improve the accessibility and the use of scientific data and information for health purposes is proposed as a basic method for better supporting Aboriginal and Torres Strait Islander primary health care workers in their practice locations. This paper explores different approaches for the development of a culturally appropriate interactive multimedia educational health program for Aboriginal and Torres Strait islander health workers and it also explore cultural matters concerning program development in the light of existing literature

    A view from the industrial age

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    Like the constructivist approach to the history of science, the new history of reading has shifted attention from disembodied ideas to the underlying material culture and the localized practices by which it is apprehended. By focusing on the complex embodied processes by which readers make sense of printed objects, historians of reading have provided new insights into the manner in which meaning is both made and contested. In this brief account I argue that these insights are particularly relevant to historians of science, first, because practices of reading, like those of experiment and fieldwork, are constitutive of scientific knowledge, and, second, because attention to the history of reading provides important evidence of the multifaceted and uneven contest for meaning that occurs when science is mobilized in popular culture. The essay concludes by considering some of the surprisingly abundant sources of available evidence from which a history of scientific reading might be constructed for the modern era
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