Since 2013, three beamlines for macromolecular crystallography are available to users at the thirdgeneration synchrotron PETRA III in Hamburg: P11, P13 and P14, the latter two operated by EMBL. Beamline P11 is operated by DESY and is equipped with a Pilatus 6M detector. Together with the photon flux of 2 × 10 13 ph/s provided by the very brilliant X-ray source of PETRA III, a full data set can be typically collected in less than 2 min. P11 provides state-of-the-art microfocusing capabilities with beam sizes down to 1 × 1 µm 2 , which makes the beamline ideally suited for investigation of microcrystals and serial crystallography experiments. An automatic sample changer allows fast sample exchange in less than 20 s, which enables high-throughput crystallography and fast crystal screening. For sample preparation, an S2 biosafety laboratory is available in close proximity to the beamline.

21We have developed a method for serial X-ray crystallography at X-ray free electron lasers (XFELs), 22 which allows for full use of the current 120 Hz repetition rate of the Linear Coherent Light Source 23 (LCLS). Using a micro-patterned silicon chip in combination with the high-speed Roadrunner 24 goniometer for sample delivery we were able to determine the crystal structures of a picornavirus, 25 bovine enterovirus 2 (BEV2), and the cytoplasmic polyhedrosis virus type 18 polyhedrin. Total data 26 collection times were less than 14 and 10 minutes, respectively. Our method requires only micrograms 27 of sample and will therefore broaden the applicability of serial femtosecond crystallography to 28 challenging projects for which only limited amounts of samples are available. By synchronizing the 29 sample exchange to the XFEL repetition rate it further allows for the most efficient use of the limited 30 beamtime available at XFELs and a significant increase in sample throughput at these facilities. 31 32 Introduction 33

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Our diffraction enhanced images represent the first radiographic detection of the structural orientation in cartilage. Our data are in line with previous studies on the structural organization of joint cartilage. They confirm the model of a vaulting system of collagen fiber bundles interrupted by proteoglycan aggregates.

Coherent diffractive imaging for the reconstruction of a two-dimensional (2D) finite crystal structure with a single pulse train of free-electron laser radiation at 7.97 nm wavelength is demonstrated. This measurement shows an advance on traditional coherent imaging techniques by applying it to a periodic structure. It is also significant that this approach paves the way for the imaging of the class of specimens which readily form 2D, but not three-dimensional crystals. We show that the structure is reconstructed to the detected resolution, given an adequate signal-to-noise ratio.

Intravenous coronary angiography with synchrotron radiation is a novel and minimally invasive technique for coronary imaging. At the Hamburger Synchrotronstrahlungslabor HASYLAB at DESY, a dedicated angiography system has been developed, which has been shown to provide detailed images of coronary artery segments. For each scan, two monochromatic X-ray images below and above the K-edge of iodine were recorded simultaneously. The two images were subtracted logarithmically to produce a maximal contrast enhancement of the iodine. To date, the procedure has been carried out on 379 outpatients. No complications occurred during or after the angiographic procedure, and hospitalization was not required in any subject. The acceptance by patient is extremely high. Five outside reviewers, blinded as to the clinical data or prior angiographic interpretation, reviewed the images for the presence or absence of 70% or more occlusion of a vessel. They reached a sensitivity of 79% and a specificity of 99%. The study has demonstrated that the synchrotron method has satisfactory sensitivity and very high specificity for severe stenoses. The new method has several advantages over magnetic resonance imaging (MRI), electron beam computed tomography (EBCT), and multi-slice computed tomography (MSCT). Neither vascular calcification (CT) nor the presence of metal stents (MRI) impairs the evaluation of perfusion of segments of the coronary arteries. Furthermore, the spatial resolution is three or four times higher using synchrotron angiography, and problems due to respiratory motion are eliminated.

Diffraction enhanced imaging (DEI) uses refraction of x-rays at edges, which allows pronounced visualization of material borders and rejects scattering which often obscures edges and blurs images. Here, the first evidence is presented that, using DEI, a destruction-free evaluation of the quality of integration of metal implants into bone is possible. Experiments were performed in rabbits and sheep with model implants to investigate the option for DEI as a tool in implant research. The results obtained from DEI were compared to conventional histology obtained from the specimens. DE images allow the identification of the quality of ingrowth of bone into the hydroxyapatite layer of the implant. Incomplete integration of the implant with a remaining gap of less than 0.3 mm caused the presence of a highly refractive edge at the implant/bone border. In contrast, implants with bone fully grown onto the surface did not display a refractive signal. Therefore, the refractive signal could be utilized to diagnose implant healing and/or loosening.

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