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Electron Beam Melting (EBM) as a means of Additive Manufacturing (AM), is of interest for the fabrication of intricate geometries for cellular materials in areas where complex architectures are needed, e.g. biomedical implants. Most studies have focused on specific geometries and so the effect of the structure on mechanical performance is not well understood. Many kinds of micro- and macro-scale defects can arise in additively manufactured components, so assessment of their influence on properties is needed. In this work, lattices of Ti-6Al-4V having a cubic structure have been manufactured by EBM, and the effect of heat treatments above and below the β-transus temperature on microstructure and compression response have been investigated. The former modifies only slightly the α + β structure and mechanical performance whereas the latter leads to coarse alternating α and β lamellae packets and α at the prior grain boundaries with a 10% loss in yield strength. The variation in the compressive yield stress with strut diameter is in good accord with simple models based on compressive deformation rather than shearing or buckling. Internal pores for struts aligned with the build direction are found around the edges of the solid form, in regions which seem to be associated with the EB scan pattern. Struts normal to the build direction show more significant defects but their redundancy means that they do not compromise the compressive performance in the build direction. Using a particle size in the range 45–100 μm minimum weld-track sizes were experimentally and numerically identified to be 176 and 148 μm in depth respectively with a depth-to-width ratio of 0.55. This produced a beam pass of the order of 300 μm oversizing small features (struts of 0.4 and 0.6 mm nominal diameter) when a contour around the strut periphery was applied. [ABSTRACT FROM AUTHOR]

Recently in Mexico the number of cosmetic surgeries has increased. These procedures are often carried out by unqualified people using obsolete and contraindicated products such as injectable oil, which cause uncorrectable disfigurement or more serious complications, even death, after reaching the systemic circulation. We report the case of a fat embolism syndrome (FES) caused by injections of vitamin E (tocopherol) in order to increase the volume of the buttocks. This case of a FES caused by injections of vitamin E was confirmed by gas chromatography coupled to mass spectrometry. [ABSTRACT FROM AUTHOR]

An investigation on the additive manufacturing and the experimental testing of 3D models of tensegrity prisms and columns is presented. An Electron Beam Melting facility (Arcam EBM S12) is employed to 3D print structures composed of tensegrity prisms endowed with rigid bases and temporary supports, which are made out of the titanium alloy Ti6Al4V. The temporary supports are removed after the additive manufacturing phase, when Spectra cross-strings are added to the 3D printed models, and a suitable state of internal prestress is applied to the structure. The experimental part of the study shows that the examined structures feature stiffening-type elastic response under large or moderately large axial strains induced by compressive loading. Such a geometrically nonlinear behavior confirms previous theoretical results available in the literature, and paves the way to the use of tensegrity prisms and columns as innovative mechanical metamaterials and smart devices. [ABSTRACT FROM AUTHOR]

Simple models describing the relationship between basic mechanical properties and the relative density of various types of porous metals (such as foams, sponges and lattice structures) are well established. Carefully evaluating these relationships experimentally is challenging, however, because of the stochastic structure of foams and the fact that it is difficult to systematically isolate density changes from variations in other factors, such as pore size and pore distribution. Here a new method for producing systematic sets of stochastic foams is employed based on electron beam melting (EBM) additive manufacturing (AM). To create idealised structures, structural blueprints were reverse-engineered by inverting X-ray computed tomographs of a randomly packed bed of glass beads. This three-dimensional structure was then modified by computer to create five foams of different relative density ρ r , but otherwise consistent structure. Yield strength and Young’s modulus have been evaluated in compression tests and compared to existing models for foams. A power of 3 rather than a squared dependence of stiffness on relative density is found, which agrees with a recent model derived for replicated foams. A similar power of 3 relation was found for yield strength. Further analysis of the strength of nominally fully dense rods of different diameters built by EBM AM suggest that surface defects mean that the minimum size of features that can be created by EBM with similar strengths to machined samples is ∼1 mm. [ABSTRACT FROM AUTHOR]

Dynamic Strain Ageing (DSA) has reached widespread acceptance since its proposal in the 1940's as the mechanism behind the Portevin-Le Chatelier effect in ferritic steels. However, it remains an open question as to whether the classical mechanism can be extended to Face-Centred Cubic (FCC) alloys, including nickel-based superalloys, as often implicitly assumed. Given the historical link between serrated flow and loss of ductility in steels, understanding such consequences in superalloys used in key components of a jet engine demands attention. This review compares plastic instabilities in superalloys to those in ferritic steels, including the effects of temperature, strain rate, compositional, microstructural and extrinsic testing parameters on the extent of serrated flow and consequences on mechanical properties. Outstanding issues are discussed in detail, relating both to the lack of a complete experimental argument depicting the origins of serrated flow and different serration 'Types', as well as the inability of current predictive models to fully account for multiscale experimental observations. Proposed explanations for plastic instabilities in FCC alloys are discussed, including but not limited to classical DSA, with the aim to guide future experiments to elucidate the origins of serrated flow across length scales and improve key properties such as fatigue life. [ABSTRACT FROM AUTHOR]

Abstract: In vitro, Imatinib inhibits the proliferation and stimulates the osteogenic and adipogenic differentiation of mesenchymal stromal cells (MSC). However, it is unknown whether Imatinib affects the biology of MSC in vivo. We asked whether MSC from long-term Imatinib-treated CML patients were affected by the in vivo treatment. MSC from untreated and Imatinib-treated patients displayed normal functional properties (i.e. proliferation, immunophenotype, differentiation and hematopoietic supportive capacity) – but a decreased frequency. In vitro, Imatinib lost its effect when discontinued; which suggest that it has a reversible effect on MSC. Therefore it might lose its effect on MSC after discontinuation in vivo. [Copyright &y& Elsevier]

An epithermal facility for treating patients with brain gliomas has been designed and is under construction at the fast reactor TAPIRO at ENEA Casaccia (Italy). The calculational design tools employed were the Monte Carlo codes MCNP/MCNPX together with the DSA in-house variance reduction patch. A realistic anthropomorphic phantom (“ADAM”) was included to optimise dose profiles and in-phantom treatment-planning figures-of-merit. The adopted approach was to minimise the treatment time whilst maintaining a reasonable therapeutic ratio. It is shown that TAPIRO, in spite of its low power of 5 kW, is able to provide an epithermal beam that is of good quality and of sufficient intensity to allow a single beam patient irradiation, under conservative assumptions, of 50 min. [Copyright &y& Elsevier]

The aims of this study were to assess epidemiology of multiple myeloma (MM) and to describe treatment patterns and economic burden among MM patients in an Italian clinical setting. Of the 547 included MM patients (mean age 68.0 years, 52.3% male), 127 were incident patients (mean age 69.4 years, 56.7% male), and 420 were prevalent patients (mean age 67.6 years, 51.0% male). Drug and outpatient service costs were higher in incident patients than prevalent, while hospitalization cost was higher in prevalent patients than incident. [Extracted from the article]

The main objective was to determine the monthly average dose for biologic drugs used for psoriasis (PSO), psoriatic arthritis (PsA) and ankylosing spondylitis (AS). For adalimumab, PSO-patients had a monthly average dose of 69, PsA-patients 73 and AS-patients 70. [Extracted from the article]

Abstract: A water-soluble [meso-tetra(4-nido-carboranylphenyl)porphyrin] (H2TCP) bearing 36 boron atoms was studied for its accumulation and its radio/photo-sensitization efficiency towards murine melanotic melanoma cells. The amount of H2TCP in the cells increased with the porphyrin dose in the incubation medium up to 100μM with no significant dark toxicity. Fluorescence microscopy observations showed that the porphyrin was largely localized intracellularly. Based on these “in vitro” results our investigations were pursued using the B16F1 melanotic melanoma subcutaneously transplanted in C57BL6 mice as “in vivo” model. Phormacokinetic studies were performed by injection of H2TCP intratumorally (1mg/kg) and intravenously (10mg/kg). At 0.5h after i.t. administration or at 24h after i.v. injection, the amountsof 10B in the tumour were about 60ppm and about 6ppm, respectively. The distribution of H2TCP in the tumour after intravenous or intratumoural injection was also assessed by fluorescence microscopy analyses. Under these conditions, preliminary BNCT studies were carried out using a new thermal column called HYTOR (HYbrid Thermal spectrum sHifter TapirO Reactor) inserted in the fast nuclear reactor Tapiro at Enea Casaccia, Italy. The mice were exposed to HYTHOR radiation field for 20min at a reactor power of 5kW. In spite of different amounts of 10B in the tumour at the irradiation time, a similar significant delay in tumour growth (5–6 days) was induced by neutron irradiation in intratoumorally and intravenously injected mice. The response of the melanotic melanoma to H2TCP-BNCT was compared with that obtained by irradiation after intraperitoneal injection of boron-phenylalanine. [Copyright &y& Elsevier]