2,717 research outputs found

    Variation in viscoelastic properties of bovine articular cartilage below, up to and above healthy gait-relevant loading frequencies

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    The aim of this study was to determine the variation in viscoelastic properties of femoral head bovine articular cartilage, on-bone, over five orders of magnitude of loading frequency. These frequencies ranged from below, up to and above healthy gait-relevant frequencies, using<1, 1–5 and 10 Hz, respectively. Dynamic mechanical analysis was used to measure storage and loss stiffness. A maximum compressive force of 36 N was applied through a chamfered-end, 5.2-mm-diameter, indenter. This induced a maximum nominal stress of 1.7 MPa. The ratio of storage to loss stiffness increased from near parity (2.5) at low frequencies to 11.4 at 10 Hz. This was the result of a significant logarithmic increase (p < 0.05) in storage stiffness with frequency, from 367 N/mm (0.001 Hz) up to 1460 N/mm (10 Hz). In contrast, the loss stiffness remained approximately constant. In conclusion, viscoelastic properties of articular cartilage measured at frequencies below those of gait activities are poor predictors of its relevant dynamic mechanical behaviour

    "Generally, I live a lie" : transgender consumer experiences and responses to symbolic violence

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    In this article, our focus is on how trans consumers experience symbolic violence to draw attention to inequalities that may otherwise remain hidden. Unlike overt acts of physical violence, symbolic violence is subtle and occurs routinely throughout the course of everyday life. We address the following research questions: how do trans consumers experience symbolic violence, what are their responses to this, and what impact does this have on their wellbeing? Our findings demonstrate that symbolic violence functions at sociocultural, interpersonal, and individual levels for trans consumers. We illustrate the tensions trans people encounter between conforming to cisgender hegemony and living an ‘authentic’ life. The subtle, naturalizing power and misrecognition of symbolic violence appears challenging for the wellbeing of transgender consumers. The lens of symbolic violence usefully informs and integrates with the consumer vulnerability perspective that has previously been used as a theoretical framework to understand transgender consumers' experiences

    Assessment of non-contacting optical methods to measure wear and surface roughness in ceramic total disc replacements

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    This study presents a method for measuring the low volumetric wear expected in ceramic total disc replacements, which can be used to replace intervertebral discs in the spine, using non-contacting optical methods. Alumina-on-alumina ball-on-disc tests were conducted with test conditions approximating those of cervical (neck region of the spine) total disc replacement wear tests. The samples were then scanned using a three-dimensional non-contacting optical profilometer and the data used to measure surface roughness and develop a method for measuring the wear volume. The results showed that the magnification of the optical lens affected the accuracy of both the surface roughness and wear volume measurements. The method was able to successfully measure wear volumes of 0.0001mm3, which corresponds to a mass of 0.0001 mg, which would have been undetectable using the gravimetric method. A further advantage of this method is that with one scan the user can measure changes in surface topography, volumetric wear and the location of the wear on the implant surface. This method could also be applied to more severe wear, other types of orthopaedic implants and different materials

    Knowledge-how, understanding-why and epistemic luck:An experimental study

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    Reductive intellectualists about knowledge-how (e.g., Stanley &amp; Williamson Journal of Philosophy 98, 411–44, 2001; Stanley Noûs 45, 207–38, 2011a, 2011b; Brogaard Philosophy Compass 3, 93–118, 2008a, Grazer Philosophische Studien 77, 147–90 2008b, Philosophy and Phenomenological Research 78, 439–67 2009, 2011) hold, contra Ryle (1946, 1949), that knowing how to do something is just a kind of propositional knowledge. In a similar vein, traditional reductivists about understanding-why (e.g., Salmon 1984; Lipton 2004; Woodward 2003; Grimm The British Journal for the Philosophy of Science 57, 515–35, 2006; Greco 2009; Kelp 2014) insist, in accordance with a tradition beginning with Aristotle, that the epistemic standing one attains when one understands why something is so is itself just a kind of propositional knowledge—viz., propositional knowledge of causes. A point that has been granted on both sides of these debates is that if these reductive proposals are right, then knowledge-how and understanding-why should be susceptible to the same extent as knowledge-that is to being undermined by epistemic luck. This paper reports experimental results that test these luck-based predictions. Interestingly, these results suggest a striking (albeit, imperfect) positive correlation between self-reported philosophical expertise and attributions of knowledge-how, understanding-why and knowledge-that which run contrary to reductive proposals. We contextualize these results by showing how they align very well with a particular kind of overarching non-reductive proposal, one that two of the authors have defended elsewhere (e.g., Carter and Pritchard Philosophy and Phenomenological Research 91, 181–99, 2015a, Noûs 49, 440–53, 2015b, Australasian Philosophical Quarterly 93, 799–816, 2015c) according to which knowledge-how and understanding-why, but not knowledge-that, essentially involve cognitive achievement (i.e., cognitive success that is primarily creditable to cognitive ability). We conclude by situating the interpretive narrative advanced within contemporary discussions about the role of expertise in philosophical judgment
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