A failure criterion for fillet welds

The work constitutes a study of the strength of mild steel fillet welds subject to static loading, and the behaviour of flange welded beam-column connections under combined bending and shear. Tests are conducted on short welds in the as-welded and stress relieved conditions, and also on full-size beam-column connections. It is shown that welds under compression have a lower strength than when under tension. Failure of the fillet weld is initiated at the weld root, the important factor controlling the initiation being weld ductility. The greater the residual stress, the lower the weld ductility and ultimate strength. Thermal stress relieving increases strength by as much as 30%. Weld failure plane is rarely at the throat and varies from 0° to 45° depending upon loading condition. Failure plane average stresses are related by a circular function which is expressed in terms of externally applied forces at limit state. The tension weld of a flange-welded beam-column connection always fails before the compression weld. The shear load sharing between the welds is a complex function of elastic compression of the web, elastic/plastic deformation of the flanges, load/deformation characteristics, and the type of load application. Bearing forces between the compression flange and column face produce low level bearing stresses and frictional forces which make a negligible contribution to shear load resistance. Three modes of connection failure are possible; 'end mode', 'bending mode' and 'shear mode', with a sudden change taking place between the two latter.

Duality of weak and strong scatterer in a Luttinger liquid coupled to massless bosons

We study electronic transport in a Luttinger liquid with an embedded impurity, which is either a weak scatterer (WS) or a weak link (WL), when interacting electrons are coupled to one-dimensional massless bosons (e.g., acoustic phonons). We find that the duality relation, ?WS?WL=1, between scaling dimensions of the electron backscattering in the WS and WL limits, established for the standard Luttinger liquid, holds in the presence of the additional coupling for an arbitrary fixed strength of boson scattering from the impurity. This means that at low temperatures such a system remains either an ideal insulator or an ideal metal, regardless of the scattering strength. On the other hand, when fermion and boson scattering from the impurity are correlated, the system has a rich phase diagram that includes a metal-insulator transition at some intermediate values of the scattering.

Clonal composition of human adamantinomatous craniopharyngiomas and somatic mutation analyses of the patched (PTCH), Gsα and Gi2α genes

Craniopharyngioma is the most common childhood tumor and thought to arise from embryonic remnants of Rathke's pouch. The paucity of published data on the molecular basis of these tumors prompted us to examine 22 adamantinomatous craniopharyngiomas looking for genetic abnormalities. Using the X-linked polymorphic androgen receptor gene as a tool for X-chromosome inactivating analysis, we found that a subset of craniopharyngiomas are monoclonal and therefore are probably due to acquired somatic genetic defects. Thus, we investigated these tumours for mutations within three candidate genes, Gsα, Gi2α and patched (PTCH). Using single stranded conformational polymorphism (SSCP), denaturing gradient gel electrophoresis and direct sequencing, the presence of somatic mutations in these genes could not be demonstrated in any tumor. Our data indicate that a subset of craniopharyngiomas are monoclonal and the mutations in the PTCH, Gsα, and Gi2α contribute little if any to cranipharyngioma development.

Granular superconductors:from the nonlinear σ model to the Bose-Hubbard description

We modify a nonlinear σ model (NLσM) for the description of a granular disordered system in the presence of both the Coulomb repulsion and the Cooper pairing. We show that under certain controlled approximations the action of this model is reduced to the Ambegaokar-Eckern-Schön (AES) action, which is further reduced to the Bose-Hubbard (or “dirty-boson”) model with renormalized coupling constants. We obtain an effective action which is more general than the AES one but still simpler than the full NLσM action. This action can be applied in the region of parameters where the reduction to the AES or the Bose-Hubbard model is not justified. This action may lead to a different picture of the superconductor-insulator transition in two-dimensional systems.

‘Death talk’, ‘loss talk’ and identification in the process of ageing

In this paper, we examine the injunction issued by the prominent politician, broadcaster and older people's advocate, Baroness Joan Bakewell, to engage in ‘death talk’. We see positive ethical potential in this injunction, insofar as it serves as a call to confront more directly the prospects of death and dying, thereby releasing creative energies with which to change our outlook on life and ageing more generally. However, when set against a culture that valorises choice, independence and control, the positive ethical potential of such injunctions is invariably thwarted. We illustrate this with reference to one of Bakewell's interventions in a debate on scientific innovation and population ageing. In examining the context of her intervention, we affirm her intuition about its positive ethical potential, but we also point to an ambivalence that accompanies the formulation of the injunction – one that ultimately blunts the force and significance of her intuition. We suggest that Gilleard and Higgs' idea of the third age/fourth age dialectic, combined with the psycho-analytic concepts of fantasy and mourning, allow us to express this intuition better. In particular, we argue that the expression ‘loss talk’ (rather than ‘death talk’) better captures the ethical negotiations that should ultimately underpin the transformation processes associated with ageing, and that our theoretical contextualisation of her remarks can help us see this more clearly. In this view, deteriorations in our physical and mental capacities are best understood as involving changes in how we see ourselves, i.e. in our identifications, and so what is at stake are losses of identity and the conditions under which we can engage in new processes of identification.

Enjoying the third age! Discourse, identity and liminality in extra-care communities

Extra-care housing has been an important and growing element of housing and care for older people in the United Kingdom since the 1990s. Previous studies have examined specific features and programmes within extra-care locations, but few have studied how residents negotiate social life and identity. Those that have, have noted that while extra care brings many health-related and social benefits, extra-care communities can also be difficult affective terrain. Given that many residents are now ‘ageing in place’ in extra care, it is timely to revisit these questions of identity and affect. Here we draw on the qualitative element of a three-year, mixed-method study of 14 extra-care villages and schemes run by the ExtraCare Charitable Trust. We follow Alemàn in regarding residents' ambivalent accounts of life in ExtraCare as important windows on the way in which liminal residents negotiate the dialectics of dependence and independence. However, we suggest that the dialectic of interest here is that of the third and fourth age, as described by Gilleard and Higgs. We set that dialectic within a post-structuralist/Lacanian framework in order to examine the different modes of enjoyment that liminal residents procure in ExtraCare's third age public spaces and ideals, and suggest that their complaints can be read in three ways: as statements about altered material conditions; as inter-subjective bolstering of group identity; and as fantasmatic support for liminal identities. Finally, we examine the implications that this latter psycho-social reading of residents' complaints has for enhancing and supporting residents' wellbeing.

Making it real of sustaining a fantasy? Personal budgets for older people

The restructuring of English social care services in the last three decades, as services are provided through a shifting collage of state, for-profit and non-profit organisations, exemplifies many of the themes of governance (Bevir, 2013). As well as institutional changes, there have been a new set of elite narratives about citizen behaviours and contributions, undergirded by modernist social science insights into the wellbeing benefits of ‘self-management’ (Mol, 2008). In this article, we particularly focus on the ways in which a narrative of personalisation has been deployed in older people’s social care services. Personalisation is based on an espoused aspiration of empowerment and autonomy through universal implementation to all users of social care (encapsulated in the Making it Real campaign [Think Local, Act Personal (TLAP), no date)], which leaves unproblematised the ever increasing residualisation of older adult social care and the abjection of the frail (Higgs and Gilleard, 2015). In this narrative of universal personalisation, older people are paradoxically positioned as ‘the unexceptional exception’; ‘unexceptional’ in the sense that, as the majority user group, they are rhetorically included in this promised transformation of adult social care; but ‘the exception’ in the sense that frail older adults are persistently placed beyond its reach. It is this paradoxical positioning of older adult social care users as the unexceptional exception and its ideological function that we seek to explain in this article.