Preliminary Evaluation of NDE Techniques for Structural Ceramics

A preliminary evaluation of several nondestructive testing methods for flaw detection in high-temperature structural ceramic components is being carried out. The ceramics components being investigated include silicon carbide heat-exchanger tubes and silicon nitride rotors. The nondestructive evaluation techniques under consideration include dye-enhanced radiography, holographic interferometry, infrared scanning, acoustic microscopy, acoustic-emission monitoring, acoustic-impact testing, and conventional ultrasonic testing. The capability of each technique to detect critical-size flaws will be discussed. Preliminary results to date\u27 have shown that (a) dye-enhanced radiographic techniques are capable of detecting tight cracks missed with conventional x-ray methods, (b) acoustic microscopy techniques may be useful in detecting and establishing the size of subsurface defects in reaction-bonded silicon nitride, (c) holographic interferometry techniques should be valuable in locating surface cracks in silicon nitride/silicon carbide components, and (d) the results from various silicon carbide tubes suggests that infrared scanning techniques may reveal changes in heat-flow patterns which are related to variations in physical properties. The results for the other techniques mentioned will be discussed. Future efforts in this program, will be directed toward in-depth investigations of the most useful nondestructive techniques

GALEX FUV Observations of Comet C/2004 Q2 (Machholz): The Ionization Lifetime of Carbon

We present a measurement of the lifetime of ground state atomic carbon, C(^3P), against ionization processes in interplanetary space and compare it to the lifetime expected from the dominant physical processes likely to occur in this medium. Our measurement is based on analysis of a far ultraviolet (FUV) image of comet C/2004 Q2 (Machholz) recorded by the Galaxy Evolution Explorer (GALEX) on 2005 March 1. The bright CI 1561 A and 1657 A multiplets dominate the GALEX FUV band. We used the image to create high S/N radial profiles that extended beyond one million km from the comet nucleus. Our measurements yielded a total carbon lifetime of 7.1 -- 9.6 x 10^5 s (scaled to 1 AU). Which compares favorably to calculations assuming solar photoionization, solar wind proton change exchange and solar wind electron impact ionization are the dominant processes occurring in this medium and that comet Machholz was embedded in the slow solar wind. The shape of the CI profiles inside 3x10^5 km suggests that either the CO lifetime is shorter than previously thought and/or a shorter-lived carbon-bearing parent molecule, such as CH_4 is providing the majority of the carbon in this region of the coma of comet Machholz.Comment: 26 pages, 6 figures, accepted for publication in the Astrophysical Journa

Expanding Transformative Experience

We develop a broader, more fine-grained taxonomy of forms of transformative experience, inspired by the work of L. A. Paul. Our vulnerability to such experiences arises, we argue, due to the vulnerability, dependence, and affliction intrinsic to the human condition. We use this trio to distinguish a variety of positively, negatively, and ambivalently valenced forms of epistemically and/or personally transformative experiences. Moreover, we argue that many transformative experiences can arise gradually and cumulatively, unfolding over the course of longer periods of time

'Education, education, education' : legal, moral and clinical

This article brings together Professor Donald Nicolson's intellectual interest in professional legal ethics and his long-standing involvement with law clinics both as an advisor at the University of Cape Town and Director of the University of Bristol Law Clinic and the University of Strathclyde Law Clinic. In this article he looks at how legal education may help start this process of character development, arguing that the best means is through student involvement in voluntary law clinics. And here he builds upon his recent article which argues for voluntary, community service oriented law clinics over those which emphasise the education of students

Dao, harmony and personhood: towards a Confucian ethics of technology

A closer look at the theories and questions in philosophy of technology and ethics of technology shows the absence and marginality of non-Western philosophical traditions in the discussions. Although, increasingly, some philosophers have sought to introduce non-Western philosophical traditions into the debates, there are few systematic attempts to construct and articulate general accounts of ethics and technology based on other philosophical traditions. This situation is understandable, for the questions of modern sciences and technologies appear to be originated from the West; at the same time, the situation is undesirable. The overall aim of this paper, therefore, is to introduce an alternative account of ethics of technology based on the Confucian tradition. In doing so, it is hoped that the current paper can initiate a relatively uncharted field in philosophy of technology and ethics of technology

Judging athletes’ moral actions: some critical reflections

Approving or disapproving of athletes’ moral conduct and character is commonplace. In this essay I explore to what extent such judgements are valid and reliable moral judgements. I identify some methodological problems associated with making moral judgements particularly, but not exclusively, from a virtue perspective. I argue that we have no reliable access to states of mind needed to make informed evaluations. Moreover, even if such access was available, the validity of our judgements would be compromised or limited by our own moral character

Fifty-Year Fate and Impact of General Medical Journals

Background: Influential medical journals shape medical science and practice and their prestige is usually appraised by citation impact metrics, such as the journal impact factor. However, how permanent are medical journals and how stable is their impact over time? Methods and Results: We evaluated what happened to general medical journals that were publishing papers half a century ago, in 1959. Data were retrieved from ISI Web of Science for citations and PubMed (Journals function) for journal history. Of 27 eligible journals publishing in 1959, 4 have stopped circulation (including two of the most prestigious journals in 1959) and another 7 changed name between 1959 and 2009. Only 6 of these 27 journals have been published continuously with their initial name since they started circulation. The citation impact of papers published in 1959 gives a very different picture from the current journal impact factor; the correlation between the two is non-significant and very close to zero. Only 13 of the 5,223 papers published in 1959 received at least 5 citations in 2009. Conclusions: Journals are more permanent entities than single papers, but they are also subject to major change and their relative prominence can change markedly over time