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Recent trends in hard X-ray micro-computed tomography (microCT) aim at increasing both spatial and temporal resolutions. These challenges require intense photon beams. Filtered synchrotron radiation beams, also referred to as `pink beams', which are emitted by wigglers or bending magnets, meet this need, owing to their broad energy range. In this work, the new microCT station installed at the biomedical beamline ID17 of the European Synchrotron is described and an overview of the preliminary results obtained for different biomedical-imaging applications is given. This new instrument expands the capabilities of the beamline towards sub-micrometre voxel size scale and simultaneous multi-resolution imaging. The current setup allows the acquisition of tomographic datasets more than one order of magnitude faster than with a monochromatic beam configuration.

The high potential of microbeam radiation therapy (MRT) in improving tumor control while reducing side effects has been shown by numerous preclinical studies. MRT offers a widened therapeutic window by using the periodical spatial fractionation of synchrotron generated x-rays into an array of intense parallel microbeams. MRT now enters a clinical transfer phase. As proof of principle and cornerstone for the safe clinical transfer of MRT, we conducted a "first in dog" trial under clinical conditions. In this report, we evaluated whether a 3-dimensional conformal MRT can be safely delivered as exclusive radiosurgical treatment in animal patients METHODS AND MATERIALS: We irradiated a 17.5-kg French bulldog for a spontaneous brain tumor (glioma suspected on magnetic resonance imaging) with conformal high-dose-rate microbeam arrays (50-µm-wide microbeams, replicated with a pitch of 400 μm) of synchrotron-generated x-rays. The dose prescription adjusted a minimal cumulated valley dose of 2.8 Gy to the plnning target volume (PTV) (cinical target volume (CTV)+ 1 mm). Thus, each beam delivered 20 to 25 Gy to the target as peak doses, and ∼1 Gy as valley doses RESULTS: The treatment was successfully delivered. Clinical follow-up over 3 months showed a significant improvement of the dog's quality of life: the symptoms disappeared. Magnetic resonance imaging, performed 3 months after irradiation, revealed reduction in tumor size (-87.4%) and mass effect with normalization of the left lateral ventricle.To our knowledge, this neuro-oncologic veterinary trial is the first 3-dimensional conformal synchrotron x-ray MRT treatment of a spontaneous intracranial tumor in a large animal. It is an essential last step toward the clinical transfer of MRT in the near future to demonstrate the feasibility and safety of treating deep-seated tumors using synchrotron-generated microbeams.

The β ( BCC ) → α ( HCP ) + β ( BCC ) phase transformation kinetics of the β -metastable titanium alloy Ti17 was studied by in situ high energy X-ray diffraction (XRD) and electrical resistivity. The use of synchrotron radiation ( E = 89.12 keV, λ = 0.01402 nm) allowed to characterize specimens 6 mm in diameter, limiting thus oxidation effects. The α + β → β phase transformation kinetics was characterized during continuous heating up to the β temperature range. The β → α + β transformation was studied in isothermal conditions (dwell at 708 ° C or 750 ° C) and during continuous cooling (cooling rates of 0.05 ° C/s, 0.1 ° C/s and 0.61 ° C/s). The evolutions of the phase fractions are analyzed and compared to kinetics measured by electrical resistivity, showing a good correlation between both methods. In addition, the evolutions of the cell parameters of each phase obtained from XRD patterns are analyzed in regard of the transformation kinetics.

A high-pressure–high-temperature gas-loading system (GLS) is described for combinedoperandoX-ray diffraction and mass spectrometry investigations during catalysed gas/solid or liquid/solid reactions. The pressure cell consists of a single-crystal sapphire tube which serves as both high-pressure container and reaction cell, with up to 6 mm inner diameter. The system can operate in two different configurations, under either static high pressure or dynamic pressurized flow. The transportable reaction cell can be filled under inert atmosphere inside a glove box, enabling studies with oxygen-sensitive compounds to be conducted. The five main benefits of this system can be summarized as follows: (i) the temperature, pressure and gas-flow ranges of 298–1273 K, 10−3 mbar–200 bar (0.1–2 × 107 Pa) and 0–1 l min−1, respectively, (ii) the combination of different gases, (iii) the flexibility of the cell design, (iv) the full rotation of the pressurized cell, and (v) the combination of X-ray diffraction and mass spectrometry as analytical tools. These key points open new possibilities for studying the evolution of catalysts or compounds from a fundamental point of view as well as for industrial applications, in both cases inoperandoconditions.