Synthesis and characterization of Ti-27.5Nb alloy made by CLAD® additive manufacturing process for biomedical applications

Biocompatible beta-titanium alloys such as Ti-27.5(at.%)Nb are good candidates for implantology and arthroplasty applications as their particular mechanical properties, including low Young’s modulus, could significantly reduce the stress-shielding phenomenon usually occurring after surgery. The CLAD® process is a powder blown additive manufacturing process that allows the manufacture of patient specific (i.e. custom) implants. Thus, the use of Ti-27.5(at.%)Nb alloy formed by CLAD® process for biomedical applications as a mean to increase cytocompatibility and mechanical biocompatibility was investigated in this study. The microstructural properties of the CLAD-deposited alloy were studied with optical microscopy and electron back-scattered diffraction (EBSD) analysis. The conservation of the mechanical properties of the Ti-27.5Nb material after the transformation steps (ingot-powder atomisation-CLAD) were verified with tensile tests and appear to remain close to those of reference material. Cytocompatibility of the material and subsequent cell viability tests showed that no cytotoxic elements are released in the medium and that viable cells proliferated well

Calculability as politics in the construction of markets: the case of socially responsible investment in France

This paper examines some of the processes by which power constitutes calculability and, in so doing, shapes the construction of markets. We combine insights from performativity studies about calculability with Lukes’ ‘radical view of power’ to investigate how multiple facets of power are mobilized to influence the creation and activities of calculative agencies in the process of market construction. An in-depth longitudinal study of the French socially responsible investment market shows how organizations acting as calculative agencies become sites of power through calculability. We identify how power is exercised over, through and against these calculative agencies by a variety of actors in order to build their position in the socially responsible investment market. Our results complement the broader question of the ‘government of economic life’ by showing how micro-level power games interact with the macro-politics of market building through calculative agencies. In so doing, our paper sheds light on neglected aspects of the changing geopolitics of calculative power in market construction and suggests approaching ‘calculability as politics’ when studying the construction of markets

The Inclusiveness and Emptiness of <i>Gong Qi</i>: A Non-Anglophone Perspective on Ethics from a Sino-Japanese Corporation

This article introduces a non-Anglophone concept of gong qi(communal vessel, 公器) as a metaphor for ‘corporation’. It contributes an endogenous perspective from a Sino-Japanese organizational context that enriches mainstream business ethics literature, otherwise heavily reliant on Western traditions. We translate the multi-layered meanings of gong qi based on analysis of its ideograms, its references into classical philosophies, and contemporary application in this Japanese multinational corporation in China. Gong qi contributes a perspective that sees a corporation as an inclusive and virtuous social entity, and also addresses the elusive, implicit, and forever evolving nature of organizational life that is rarely noticed. We propose gong qi can be applied in other organizations and wider cultural contexts to show a new way of seeing and understanding business ethics and organization. Rather than considering virtue as a list of definable individual qualities, we suggest that the metaphor of gong qi reveals how virtue can be experienced as indeterminate, yet immanently present, like the substance of emptiness. This, then allows us to see the virtue of immanence, the beauty of implicitness, and hence, the efficacy of gong qi

Good to be bad : should we be worried by the sharing economy?

We develop the notion of a legitimacy tipping point to demonstrate how informal economy practices are being utilized by innovative sharing economy ventures to gain a competitive advantage that is subsequently leveraged to reconfigure formal institutional arrangements. Companies who are able to scale rapidly can afford to contravene regulations, provided they have public support. When they reach a certain size, in terms of investment and customer numbers, regulators are forced into a reactive position where novel business models are legitimized. This raises an important question for regulators and entrepreneurs as to whether subverting business regulation is being viewed as a viable source of competitive advantage by scaling firms

Characterization of direct laser deposited low modulus Ti-26Nb alloy on Ti-6Al-4V for biomedical applications

International audienc

Microstructural analyses of Ti-6Al-4V samples made by additive manufacturing

National audienc

The DCRS: Dynamic compaction resistance sintering. A flash sintering process with a dynamic loading ability

A homemade powder processing device combining Joule heating and dynamic compaction is presented. This device has been tested at temperatures as high as 1850 ∘C with heating rates up to 1000 ∘C/min. A detailed description of this device is given here followed by mechanical response and thermal validation tests. This highlights the reproducibility of the results on both the thermal and mechanical point of view

Welding Thermal Cycle Impact on the Microstructure and Mechanical Properties of Thermo-Mechanical Control Process Steels

Steels obtained by the thermo?mechanical control process (TMCP) possess a higher level of strength than conventional normalized steels due to the fine-grained microstructures generated during TMCP. Such enhancement opens ways to decrease metal construction weight. At the same time, TMCP steels have less thermal stability, in connection with a lot of factors affecting and governing grain growth during the heating of TMCP steels. Herein, the effects of the welding thermal cycle (WTC) on the structure and properties of TMCP steels of ferritic?perlite (S460M) and bainitic (alform 620M) types are systematically investigated. ? 2021 Wiley-VCH GmbH11Nsciescopu

Activation of the alternative pathway of complement during the acute phase of typical haemolytic uraemic syndrome

Haemolytic uraemic syndrome (HUS) is characterized by haemolytic anaemia, thrombocytopenia and acute renal failure. We studied the activation state of classical and alternative pathways of complement during the acute phase of Shiga toxin-associated HUS by performing a prospective study of 18 patients and 17 age-matched healthy controls to evaluate C3, C3c, C4, C4d, Bb and SC5b-9 levels. SC5b-9 levels were increased significantly in all patients at admission compared to healthy and end-stage renal disease controls, but were significantly higher in patients presenting with oliguria compared to those with preserved diuresis. C3 and C4 levels were elevated significantly at admission in the non-oliguric group when compared to controls. No significant differences were found for C4d values, whereas factor Bb was elevated in all patients and significantly higher in oliguric patients when compared to both controls and non-oliguric individuals. A positive and significant association was detected when Bb formation was plotted as a function of plasma SC5b-9 at admission. Bb levels declined rapidly during the first week, with values not significantly different from controls by days 3 and 5 for non-oligurics and oligurics, respectively. Our data demonstrate the activation of the alternative pathway of complement during the acute phase of Stx-associated HUS. This finding suggests that complement activation may represent an important trigger for the cell damage that occurs during the syndrome.Fil: Ferraris, J. R.. Hospital Italiano de Buenos Aires; Argentina. Universidad de Buenos Aires. Facultad de Medicina; ArgentinaFil: Ferraris, V.. Hospital Italiano de Buenos Aires; ArgentinaFil: Acquier, Andrea Beatriz. Universidad de Buenos Aires. Facultad de Odontología. Cátedra de Farmacología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas; Argentina; ArgentinaFil: Sorroche, P. B.. Hospital Italiano de Buenos Aires; ArgentinaFil: Saez, M. S.. Hospital Italiano de Buenos Aires; ArgentinaFil: Ginaca, A.. Gobierno de la Ciudad de Buenos Aires. Hospital General de Niños "Ricardo Gutierrez"; ArgentinaFil: Mendez, Carlos Fernando. Universidad de Buenos Aires. Facultad de Odontología. Cátedra de Farmacología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas; Argentina; Argentin