829 research outputs found

    Physical education as Olympic education

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    Introduction In a recent paper (Parry, 1998, p. 64), I argued that the justification of PE activities lies in their capacity to facilitate the development of certain human excellences of a valued kind. Of course, the problem now lies in specifying those ‘human excellences of a valued kind’, and (for anyone) this task leads us into the area of philosophical anthropology. I suggested that the way forward for Physical Education lies in the philosophical anthropology (and the ethical ideals) of Olympism, which provide a specification of a variety of human values and excellences which: ‱have been attractive to human groups over an impressive span of time and space ‱have contributed massively to our historically developed conceptions of ourselves ‱have helped to develop a range of artistic and cultural conceptions that have defined Western culture. ‱have produced a range of physical activities that have been found universally satisfying and challenging. Although physical activities are widely considered to be pleasurable, their likelihood of gaining wide acceptance lies rather in their intrinsic value, which transcends the simply hedonic or relative good. Their ability to furnish us with pleasurable experiences depends upon our prior recognition in them of opportunities for the development and expression of valued human excellences. They are widely considered to be such opportunities for the expression of valued human excellences because, even when as local instantiations, their object is to challenge our common human propensities and abilities. I claimed that Olympic ideals may be seen not merely as inert ‘ideals’, but living ideas which have the power to remake our notions of sport in education, seeing sport not as mere physical activity but as the cultural and developmental activity of an aspiring, achieving, well-balanced, educated and ethical individual. This paper seeks to make good that claim by trying to develop a case for Physical Education as Olympic Education. I begin by setting out various accounts and conceptions of the Olympic Idea; then I suggest a unifying and organising account of the philosophical anthropology of Olympism; and this is followed by the practical application of that account in two examples of current ethical issues. Finally, I seek to present an account of Physical Education as Olympic Education

    Aerobic scope protection reduces ectotherm growth under warming

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    1. Temperature has a dramatic effect on the physiology of ectothermic animals, impacting most of their biology. When temperatures increase above optimal for an animal, their growth gradually decreases. The main mechanism behind this growth rate reduction is unknown. 2. Here, we suggest the 'aerobic scope protection' hypothesis as a mechanistic explanation for the reduction in growth. 3. After a meal, metabolic rate, and hence oxygen consumption rate, transiently increase in a process called specific dynamic action (SDA). At warmer temperatures, the SDA response usually becomes temporally compressed, leading to a higher peak oxygen consumption rate. This peak in oxygen consumption rate risks taking up much of the animal's aerobic scope (the difference between resting and maximum rates of oxygen consumption), which would leave little residual aerobic scope for other aerobic functions. 4. We propose that water-breathing ectothermic animals will protect their postprandial residual aerobic scope by reducing meal sizes in order to regulate the peak SDA response during times of warming, leading to reductions in growth. 5. This hypothesis is consistent with the published literature on fishes, and we provide predictions that can be tested.Peer reviewe

    Neutrino induced transitions between the ground states of the A=12 triad

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    Neutrino induced reactions on 12^{12}C, an ingredient of liquid scintillators, have been studied in several experiments. We show that for currently available neutrino energies, EΜ≀E_{\nu} \le 300 MeV, calculated exclusive cross sections 12^{12}Cgs(Îœ,l)_{gs}(\nu,l)12^{12}Ngs_{gs} for both muon and electron neutrinos are essentially model independent, provided the calculations simultaneously describe the rates of several other reactions involving the same states or their isobar analogs. The calculations agree well with the measured cross sections, which can be therefore used to check the normalization of the incident neutrino spectrum and the efficiency of the detector.Comment: 9 pages REVTEX, 2 postscript figures, text and figures available at http://www.krl.caltech.edu/preprints/MAP.htm

    The host metabolite D-serine contributes to bacterial niche specificity through gene selection

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    Escherichia coli comprise a diverse array of both commensals and niche-specific pathotypes. The ability to cause disease results from both carriage of specific virulence factors and regulatory control of these via environmental stimuli. Moreover, host metabolites further refine the response of bacteria to their environment and can dramatically affect the outcome of the host–pathogen interaction. Here, we demonstrate that the host metabolite, D-serine, selectively affects gene expression in E. coli O157:H7. Transcriptomic profiling showed exposure to D-serine results in activation of the SOS response and suppresses expression of the Type 3 Secretion System (T3SS) used to attach to host cells. We also show that concurrent carriage of both the D-serine tolerance locus (dsdCXA) and the locus of enterocyte effacement pathogenicity island encoding a T3SS is extremely rare, a genotype that we attribute to an ‘evolutionary incompatibility’ between the two loci. This study demonstrates the importance of co-operation between both core and pathogenic genetic elements in defining niche specificity

    Precision of the PET activity range during irradiation with <sup>10</sup>C, <sup>11</sup>C, and <sup>12</sup>C beams

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    Objective. Beams of stable ions have been a well-established tool for radiotherapy for many decades. In the case of ion beam therapy with stable 12C ions, the positron emitters 10,11C are produced via projectile and target fragmentation, and their decays enable visualization of the beam via positron emission tomography (PET). However, the PET activity peak matches the Bragg peak only roughly and PET counting statistics is low. These issues can be mitigated by using a short-lived positron emitter as a therapeutic beam. Approach. An experiment studying the precision of the measurement of ranges of positron-emitting carbon isotopes by means of PET has been performed at the FRS fragment-separator facility of GSI Helmholtzzentrum fĂŒr Schwerionenforschung GmbH, Germany. The PET scanner used in the experiment is a dual-panel version of a Siemens Biograph mCT PET scanner. Main results. High-quality in-beam PET images and activity distributions have been measured from the in-flight produced positron emitting isotopes 11C and 10C implanted into homogeneous PMMA phantoms. Taking advantage of the high statistics obtained in this experiment, we investigated the time evolution of the uncertainty of the range determined by means of PET during the course of irradiation, and show that the uncertainty improves with the inverse square root of the number of PET counts. The uncertainty is thus fully determined by the PET counting statistics. During the delivery of 1.6 × 107 ions in 4 spills for a total duration of 19.2 s, the PET activity range uncertainty for 10C, 11C and 12C is 0.04 mm, 0.7 mm and 1.3 mm, respectively. The gain in precision related to the PET counting statistics is thus much larger when going from 11C to 10C than when going from 12C to 11C. The much better precision for 10C is due to its much shorter half-life, which, contrary to the case of 11C, also enables to include the in-spill data in the image formation. Significance. Our results can be used to estimate the contribution from PET counting statistics to the precision of range determination in a particular carbon therapy situation, taking into account the irradiation scenario, the required dose and the PET scanner characteristics.</p

    Induced pseudoscalar coupling of the proton weak interaction

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    The induced pseudoscalar coupling gpg_p is the least well known of the weak coupling constants of the proton's charged--current interaction. Its size is dictated by chiral symmetry arguments, and its measurement represents an important test of quantum chromodynamics at low energies. During the past decade a large body of new data relevant to the coupling gpg_p has been accumulated. This data includes measurements of radiative and non radiative muon capture on targets ranging from hydrogen and few--nucleon systems to complex nuclei. Herein the authors review the theoretical underpinnings of gpg_p, the experimental studies of gpg_p, and the procedures and uncertainties in extracting the coupling from data. Current puzzles are highlighted and future opportunities are discussed.Comment: 58 pages, Latex, Revtex4, prepared for Reviews of Modern Physic

    Motor Preparatory Activity in Posterior Parietal Cortex is Modulated by Subjective Absolute Value

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    For optimal response selection, the consequences associated with behavioral success or failure must be appraised. To determine how monetary consequences influence the neural representations of motor preparation, human brain activity was scanned with fMRI while subjects performed a complex spatial visuomotor task. At the beginning of each trial, reward context cues indicated the potential gain and loss imposed for correct or incorrect trial completion. FMRI-activity in canonical reward structures reflected the expected value related to the context. In contrast, motor preparatory activity in posterior parietal and premotor cortex peaked in high “absolute value” (high gain or loss) conditions: being highest for large gains in subjects who believed they performed well while being highest for large losses in those who believed they performed poorly. These results suggest that the neural activity preceding goal-directed actions incorporates the absolute value of that action, predicated upon subjective, rather than objective, estimates of one's performance

    Parallel processes:Getting it write?

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    This paper offers a critical reflection on the processes surrounding the writing of a book aimed at foster carers and residential workers. By utilising the concept of parallel process as well as the four modes of reflection identified by Ruch (2000), we explore the ways in which the wider context of both direct works with children and reflective practice have been impacted by the tensions between relationally based, child-centred practice and wider managerialist imperatives. The paper draws parallels between these practice tensions and those currently in play within the academy. By employing a dialogical and reflective analysis of the process and interactions surrounding the writing of a practitioner-targeted book, the paper demonstrates the ways in which critical and process reflection post-event took place, considering the heretofore unexplored parallel processes between writing for practice, and practice. In so doing, it identifies the ways in which the authors mirrored practitioners in relation to the management of anxiety, a sense of constrained autonomy and confidence, and an avoidance of recognising and challenging structural and political context. Implications for the creation of practice literature and for the academy are considered.Output Status: Forthcoming/Available Onlin

    Robust estimation of microbial diversity in theory and in practice

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    Quantifying diversity is of central importance for the study of structure, function and evolution of microbial communities. The estimation of microbial diversity has received renewed attention with the advent of large-scale metagenomic studies. Here, we consider what the diversity observed in a sample tells us about the diversity of the community being sampled. First, we argue that one cannot reliably estimate the absolute and relative number of microbial species present in a community without making unsupported assumptions about species abundance distributions. The reason for this is that sample data do not contain information about the number of rare species in the tail of species abundance distributions. We illustrate the difficulty in comparing species richness estimates by applying Chao's estimator of species richness to a set of in silico communities: they are ranked incorrectly in the presence of large numbers of rare species. Next, we extend our analysis to a general family of diversity metrics ("Hill diversities"), and construct lower and upper estimates of diversity values consistent with the sample data. The theory generalizes Chao's estimator, which we retrieve as the lower estimate of species richness. We show that Shannon and Simpson diversity can be robustly estimated for the in silico communities. We analyze nine metagenomic data sets from a wide range of environments, and show that our findings are relevant for empirically-sampled communities. Hence, we recommend the use of Shannon and Simpson diversity rather than species richness in efforts to quantify and compare microbial diversity.Comment: To be published in The ISME Journal. Main text: 16 pages, 5 figures. Supplement: 16 pages, 4 figure
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