A physics-based life prediction methodology for thermal barrier coating systems

A novel mechanistic approach is proposed for the prediction of the life of thermal barrier coating (TBC) systems. The life prediction methodology is based on a criterion linked directly to the dominant failure mechanism. It relies on a statistical treatment of the TBC's morphological characteristics, non-destructive stress measurements and on a continuum mechanics framework to quantify the stresses that promote the nucleation and growth of microcracks within the TBC. The last of these accounts for the effects of TBC constituents' elasto-visco-plastic properties, the stiffening of the ceramic due to sintering and the oxidation at the interface between the thermally insulating yttria stabilized zirconia (YSZ) layer and the metallic bond coat. The mechanistic approach is used to investigate the effects on TBC life of the properties and morphology of the top YSZ coating, metallic low-pressure plasma sprayed bond coat and the thermally grown oxide. Its calibration is based on TBC damage inferred from non-destructive fluorescence measurements using piezo-spectroscopy and on the numerically predicted local TBC stresses responsible for the initiation of such damage. The potential applicability of the methodology to other types of TBC coatings and thermal loading conditions is also discussed

Suited for Success? : Suits, Status, and Hybrid Masculinity

This document is the Accepted Manuscript version. The final, definitive version of this paper has been published in Men and Masculinities, March 2017, doi: https://doi.org/10.1177/1097184X17696193, published by SAGE Publishing, All rights reserved.This article analyzes the sartorial biographies of four Canadian men to explore how the suit is understood and embodied in everyday life. Each of these men varied in their subject positions—body shape, ethnicity, age, and gender identity—which allowed us to look at the influence of men’s intersectional identities on their relationship with their suits. The men in our research all understood the suit according to its most common representation in popular culture: a symbol of hegemonic masculinity. While they wore the suit to embody hegemonic masculine configurations of practice—power, status, and rationality—most of these men were simultaneously marginalized by the gender hierarchy. We explain this disjuncture by using the concept of hybrid masculinity and illustrate that changes in the style of hegemonic masculinity leave its substance intact. Our findings expand thinking about hybrid masculinity by revealing the ways subordinated masculinities appropriate and reinforce hegemonic masculinity.Peer reviewe

Doing it for the kids?: The discursive construction of the teenager and teenage sexuality in E4’s Skins

The teen series is often regarded by television scholars as an inherently American genre. Indeed, the genre is marked by US constructs, such as the cheerleader, jock, homecoming dance and prom and, in turn, teen television scholarship has focused almost exclusively on US texts. However, more recent years have seen the emergence of British teen drama series, most notably Skins (E4, 2007-), which has been so successful that it has spawned an (albeit short-lived) US version which aired on MTV. In an attempt to redress the dearth of academic study of British teen dramas, this article explores Skins in more detail. Journalistic discourse on the programme has frequently emphasised the series' nihilism in contrast to the didacticism that characterises its US generic counterparts, which the series' creators justify by claims for its authenticity. This article moves beyond the authentic/inauthentic debate to explore instead the discursive construction of the teenager and teenage sexuality in the specific context of broadcasting in the UK. Thus, after situating Skins in relation to the history of youth programming in Britain and, specifically, on Channel 4, the article will explore issue-led storylines involving teenage sexuality in more detail. It will argue that despite the programme's nihilistic ethos, Skins is underpinned by more conservative ideologies, particularly regarding the depiction of gender and sexuality. In turn, this ambivalence makes it difficult to discern the programme's ideological stance on sexual issues

Magazine and reader constructions of 'metrosexuality' and masculinity: a membership categorisation analysis

Since the launch of men's lifestyle magazines in the 1980s, academic literature has predominantly focused on them as a cultural phenomenon arising from entrepreneurial and commercial initiatives and/or as cultural texts that proffer representations of masculinity such as 'new lad' and 'new dad'. This paper steps aside from the focus on culture and, instead, treats magazine content as a discursive space in which gender and sexuality are oriented to, negotiated, and accomplished within and beyond the magazine itself (i.e. through readers' responses). Specifically, membership categorisation analysis is deployed to explore how the relatively new (and perhaps alternative) category for men - 'metrosexual' - is presented and received. Our analysis suggests that masculinity concerns are central in debates about 'metrosexuality', with self-identified 'metrosexuals' invoking heterosexual prowess and self-respect on the one hand, and critics (e.g. selfidentified 'real men') lamenting 'metrosexuality' for its perceived effeminacy and lack of authenticity on the other. Implications for understanding contemporary masculinities are discussed

A software tool for lifetime prediction of thermal barrier coating systems

Thermal barrier coatings (TBCs) are widely used to extend the lifetime of key components within gas turbines, and so the ability to predict the lifetime of TBCs is a high priority for gas turbine users. A complete model of TBC failure requires characterisation of the coating system, identification of the main failure mechanisms, quantitative description of stress evolution in the key areas within the coating system and robust failure criteria for each failure mechanism. Thus lifetime prediction invariably requires a massive effort both in terms of determining the appropriate input parameters for the model and in computing the solution. In order to reduce the need for extensive calculation, a software tool has been developed that interpolates the key stresses for each failure mechanism from a matrix of previously calculated values. The matrix of values is generated using a recently developed finite element (FE) model of TBC lifetime of an IN738/MCrAlY/ EB-PVD YSZ system. The stress distribution predicted by this model is dependent on exposure time and temperature as well as the morphology of the bond coat/ceramic interface and requires FE calculation for each specific set of conditions. The software tool interpolates the FE results with respect to time, temperature and a geometric parameter to predict key stresses that drive failure, and coating system lifetime. This paper describes the principles behind the development of the algorithms implemented in the software tool. Validation of the approach is in progress through comparison of predictions with non-destructive measurements on the coating system

A generation apart? Youth and political participation in Britain

Conventional wisdom holds that young people in Britain are alienated from politics, with some claiming that this reflects a wider crisis of legitimacy that should be met by initiatives to increase citizenship. This article addresses these areas, presenting both panel survey and focus group data from first-time voters. It concludes that, contrary to the findings from many predominantly quantitative studies of political participation, young people are interested in political matters, and do support the democratic process. However they feel a sense of anti-climax having voted for the first time, and are critical of those who have been elected to positions of political power. If they are a generation apart, this is less to do with apathy, and more to do with their engaged scepticism about ‘formal’ politics in Britain

Negative energy balance in dairy cows is associated with specific changes in IGF-binding protein expression in the oviduct

Negative energy balance (NEB) during early lactation in dairy cows leads to an altered metabolic state that has major effects on the production of IGF family members. Low IGF-I concentrations are associated with poor fertility and therefore we aimed to determine whether NEB exerts a direct effect on IGF expression in the postpartum oviduct. Multiparous Holstein cows were allocated to two treatments (each n=6) designed using differential feeding and milking regimes to produce either mild NEB (MNEB) or severe NEB (SNEB). Animals were slaughtered in week 2 of lactation when divergent metabolic profiles were evident. Oviducts were collected for RNA analysis by real-time RT-PCR and in situ hybridisation. Quantitative measures in oviduct gene expression were obtained for all members of the IGF family (IGF-I/II, IGF-binding proteins (IGFBP) 1–6 and receptors for IGF types 1 and 2), insulin A/B, GH, glucocorticoid and oestrogen α/β. Expression of IGFBP-2 and IGFBP-6 (both of which have a high affinity for IGF-II) was decreased in SNEB relative to MNEB (P<0.05). No other gene was altered by NEB, but IGF-II, IGFBP-3, IGFBP-5 and IGFBP-6 all showed differential expression in different regions of the oviduct. These results indicate that, in addition to low circulating IGF-I after calving, NEB may also influence IGF availability in the oviduct indirectly through changes in specific IGFBP expression. It is possible that the predicted increased signalling by IGF-II may perturb embryo development, contributing to the high rates of embryonic mortality in dairy cows

Kinetin riboside and its ProTides activate the Parkinson's disease associated PTEN-induced putative kinase 1 (PINK1) independent of mitochondrial depolarization

Since loss of function mutations of PINK1 lead to early-onset Parkinson’s disease, there has been growing interest in the discovery of small molecules that amplify the kinase activity of PINK1. We herein report the design, synthesis, serum stability and hydrolysis of four kinetin riboside ProTides. These ProTides, along with kinetin riboside, activated PINK1 in cells independent of mitochondrial depolarization. This highlights the potential of modified nucleosides and their phosphate prodrugs as treatments for neurodegenerative diseases

Reframing gender and feminist knowledge construction in marketing and consumer research: missing feminisms and the case of men and masculinities

Gender has been theorised and studied in many ways and across different disciplines. Although a number of these theorisations have been recognised and adopted in marketing and consumer research, the significance of feminism in knowledge construction has largely remained what we would call ‘unfinished’. Based on a critical reframing of gender research in marketing and consumer research, in dialogue with feminist theory, this article offers theoretical and practical suggestions for how to reinvigorate these research efforts. The analysis highlights dominant theorisations of gender, relating to gender as variable, difference and role; as fundamental difference and structuring; and as cultural and identity constructions. This reframing emphasises various neglected or ‘missing feminisms’, including queer theory; critical race, intersectional and transnational feminisms; material-discursive feminism; and critical studies on men and masculinities. A more detailed discussion of the latter, as a relatively new, growing and politically contentious area, is further developed to highlight more specifically which feminist and gender theories are mainly in use in marketing and consumer research and which are little or not used. In the light of this, it is argued that marketing and related disciplines have thus far largely neglected several key contemporary gender and feminist theorisations, particularly those that centre on gender power relations. The potential impact of these theoretical frames on transdisciplinary studies in marketing and consumer research and research agenda(s) is discussed

Computer-based technology and student engagement: a critical review of the literature

Computer-based technology has infiltrated many aspects of life and industry, yet there is little understanding of how it can be used to promote student engagement, a concept receiving strong attention in higher education due to its association with a number of positive academic outcomes. The purpose of this article is to present a critical review of the literature from the past 5 years related to how web-conferencing software, blogs, wikis, social networking sites (Facebook and Twitter), and digital games influence student engagement. We prefaced the findings with a substantive overview of student engagement definitions and indicators, which revealed three types of engagement (behavioral, emotional, and cognitive) that informed how we classified articles. Our findings suggest that digital games provide the most far-reaching influence across different types of student engagement, followed by web-conferencing and Facebook. Findings regarding wikis, blogs, and Twitter are less conclusive and significantly limited in number of studies conducted within the past 5 years. Overall, the findings provide preliminary support that computer-based technology influences student engagement, however, additional research is needed to confirm and build on these findings. We conclude the article by providing a list of recommendations for practice, with the intent of increasing understanding of how computer-based technology may be purposefully implemented to achieve the greatest gains in student engagement. © 2017, The Author(s)