Development of welding techniques and filler metals for high strength aluminum alloys second quarterly report, 1 oct. - 31 dec. 1964

Welding techniques and filler metals for high strength aluminum alloys evaluated by bulge test progra

Development of welding techniques and filler metals for high strength aluminum alloys Annual summary report, 27 Jun. 1964 - 27 Jun. 1965

Welding techniques and filler metals for high strength aluminum alloy

Off the track: A profile of non-tenure track faculty at McGill University

A survey conducted at McGill University suggests that non-tenure track faculty are a diverse group of highly-qualified individuals whose employment status involves a high degree of uncertainty. In accordance with other Canadian and American studies, the survey also found that a disproportionate number of women occupy non-tenure track as opposed to tenured or tenure track positions. Since the 1980s, North American universities have responded to increasing student enrollments and con- tinued cuts to government funding by appointing significant numbers of faculty to full-time and part-time non-tenure track positions. Due to the precariousness of their employment status, non-tenure track faculty rep- resent an attractive buffer in times of financial restraint. Despite their increasing numbers, however, little is known about the composition and concerns of non-tenure track faculty as a group. This article describes this group at one university and puts into question the structural and power relations that have led to their increased use and abuse.Une étude faite à l'université McGill suggère que le corps enseignant dont le statut ne donne pas accès à la permanence est fortement diversifié et composé d'individus très qualifiés, mais que ce même statut implique une grande incertitude d'emploi. A l'instar des études canadiennes et américaines, cette étude montre également qu'à l'université McGill, un nombre disproportionné de femmes occupent des postes qui ne donnent pas accès à la permanence par opposition à des postes permanents ou qui donnent accès à la permanence. Depuis les années 1980, les universités Nord-américaines ont réagi à l'accroissement de la clientèle étudiante et aux compressions répétées des subventions de l'État en embauchant un nombre important d'enseignants à des postes à temps partiel ou plein temps qui ne donnent pas accès à la permanence. La précarité inhérente à ce statut d'emploi est une solution attrayante en période de restriction budgétaire. Quoique le nombre de postes soit en croissance constante, on connait peu de choses sur la composition de ce groupe et leurs préoccupations à propos de leur statut. Cet article décrit un groupe dans une université et soulève des questions de relations structurales et de pouvoir qui ont mené à accroître et à abuser de cette forme d'emploi

Immunohistochemical detection of ERβ in breast cancer: towards more detailed receptor profiling?

Oestrogen receptor (ER) is used routinely to predict endocrine responsiveness in patients with breast cancer. A second ER, ERβ has been described but its significance remains undefined; most studies have described mRNA levels rather than protein expression. Here, we demonstrate for the first time, immunohistochemical detection of ERβ in archival breast tumours. © 2001 Cancer Research Campaignhttp://www.bjcancer.co

Design Enhancement of Biomedical Scaffolds Made By Selective Laser Melting

Selective laser melting (SLM) is increasingly used to fabricate biomedical scaffolds. However, the intrinsic specifications of the process such as laser spot size, layer thickness, and particle size limit the production accuracy, altering the geometrical characteristics and mechanical properties of the scaffolds. This work attempts to assess and improve the mechanical properties of TiAl6V4 biomedical scaffolds by eliminating/modifying the sharp and thin nodes (as the main source of stress concentrations and lowering the mechanical properties). This is carried out through a gradual increase of the beam (strut) thickness around the nodes where corresponding struts meet. The compression performance of these scaffolds was assessed and compared to common examples (unaltered struts) and to scaffolds designed with thicker struts in the centre of the beams (demonstrating the largest contrast). The findings prove that the thickening of the nodal points improves the strain distribution while maintains the mechanical properties at an identical solid volume fraction. This can be used to improve the scaffold design by a gradual strut thickness (in a comparable volume fraction) for an improved bio-mechanical performance.Mechanical Engineerin

Development and characterisation of a 3D multi-cellular in vitro model of normal human breast: a tool for cancer initiation studies.

Multicellular 3-dimensional (3D) in vitro models of normal human breast tissue to study cancer initiation are required. We present a model incorporating three of the major functional cell types of breast, detail the phenotype and document our breast cancer initiation studies. Myoepithelial cells and fibroblasts were isolated and immortalised from breast reduction mammoplasty samples. Tri-cultures containing non-tumorigenic luminal epithelial cells HB2, or HB2 overexpressing different HER proteins, together with myoepithelial cells and fibroblasts were established in collagen I. Phenotype was assessed morphologically and immunohistochemically and compared to normal breast tissue. When all three cell types were present, polarised epithelial structures with lumens and basement membrane production were observed, akin to normal human breast tissue. Overexpression of HER2 or HER2/3 caused a significant increase in size, while HER2 overexpression resulted in development of a DCIS-like phenotype. In summary, we have developed a 3D tri-cellular model of normal human breast, amenable to comparative analysis after genetic manipulation and with potential to dissect the mechanisms behind the early stages of breast cancer initiation

Rheological behavior of β-Ti and NiTi powders produced by atomization for SLM production of open porous orthopedic implants

The growing interest for Selective Laser Melting (SLM) in orthopedic implant manufacturing is accompanied by the introduction of novel Ti alloys, in particular β-Ti for their excellent corrosion resistance as well as favorable combination of high mechanical strength, fatigue resistance and relatively low elastic modulus. As part of the SLM process for producing quality β-Ti parts powder flowability is essential to achieve uniform thickness of powder layers. In this work the flowability of different gas atomized β-Ti, including NiTi, powders has been studied. Their rheological properties were compared to those of commercially available plasma-atomized Ti–6Al–4V powder using a newly developed semi-automatic experimental set-up. Not only the particle size, shape and size distribution of the powders display a large influence on the powder flowability but also particle surface properties such as roughness, chemical composition and the presence of liquid on the surface of the particles. It was found that plasma or gas atomization production techniques for SLM powder have a considerable effect on the particle topography. Among the powders studied regarding SLM applicability only rheological properties of the fine size fraction (25–45 μm) of Ti–45Nb didn't conform to SLM processing requirements. To improve flowability of the Ti–45Nb powder itwas annealed both in air and argon atmosphere at 600 °C during 1 h, resulting in an improved rheological behavior suitable for SLM processing