First operation of the JUNGFRAU detector in 16-memory cell mode at European XFEL

The JUNGFRAU detector is a well-established hybrid pixel detector developed at the Paul Scherrer Institut (PSI) designed for free-electron laser (FEL) applications. JUNGFRAU features a charge-integrating dynamic gain switching architecture, with three different gain stages and 75 μm pixel pitch. It is widely used at the European X-ray Free-Electron Laser (EuXFEL), a facility which produces high brilliance X-ray pulses at MHz repetition rate in the form of bursts repeating at 10 Hz. In nominal configuration, the detector utilizes only a single memory cell and supports data acquisition up to 2 kHz. This constrains the operation of the detector to a 10 Hz frame rate when combined with the pulsed train structure of the EuXFEL. When configured in so-called burst mode, the JUNGFRAU detector can acquire a series of images into sixteen memory cells at a maximum rate of around 150 kHz. This acquisition scheme is better suited for the time structure of the X-rays as well as the pump laser pulses at the EuXFEL. To ensure confidence in the use of the burst mode at EuXFEL, a wide range of measurements have been performed to characterize the detector, especially to validate the detector alibration procedures. In particular, by analyzing the detector response to varying photon intensity (so called ‘intensity scan’), special attention was given to the characterization of the transitions between gain stages. The detector was operated in both dynamic gain switching and fixed gain modes. Results of these measurements indicate difficulties in the characterization of the detector dynamic gain switching response while operated in burst mode, while no major issues have been found with fixed gain operation. Based on this outcome, fixed gain operation mode with all the memory cells was used during two experiments at EuXFEL, namely in serial femtosecond protein crystallography and Kossel lines measurements. The positive outcome of these two experiments validates the good results previously obtained, and opens the possibility for a wider usage of the detector in burst operation mode, although compromises are needed on the dynamic range

3D atomic structure from a single X-ray free electron laser pulse

Abstract X-ray Free Electron Lasers (XFEL) are cutting-edge pulsed x-ray sources, whose extraordinary pulse parameters promise to unlock unique applications. Several new methods have been developed at XFELs; however, no methods are known, which allow ab initio atomic level structure determination using only a single XFEL pulse. Here, we present experimental results, demonstrating the determination of the 3D atomic structure from data obtained during a single 25 fs XFEL pulse. Parallel measurement of hundreds of Bragg reflections was done by collecting Kossel line patterns of GaAs and GaP. To the best of our knowledge with these measurements, we reached the ultimate temporal limit of the x-ray structure solution possible today. These measurements open the way for obtaining crystalline structures during non-repeatable fast processes, such as structural transformations. For example, the atomic structure of matter at extremely non-ambient conditions or transient structures formed in irreversible physical, chemical, or biological processes may be captured in a single shot measurement during the transformation. It would also facilitate time resolved pump-probe structural studies making them significantly shorter than traditional serial crystallography

New Immunochromatographic Rapid Test for Diagnosis of Acute Puumala Virus Infection

A new immunochromatographic rapid test, POC PUUMALA (Erilab Ltd., Kuopio, Finland), for detection of acute-phase Puumala virus (PUUV) infection was developed based on a highly purified baculovirus-expressed PUUV nucleocapsid protein antigen and lateral immunodiffusion techniques. After addition of sample (5 μl of serum, plasma, or fingertip blood) and buffer, PUUV-specific immunoglobulin M (IgM) antibodies, if present, together with the gold-conjugated anti-human IgM, formed a specific colored line in 5 min. The sensitivity and specificity of the test were evaluated with 200 serum samples and 30 fingertip blood samples. The reference method for the serum samples was a μ-capture enzyme immunoassay (EIA) for IgM and an immunofluorescence assay (IFA) for IgG antibodies. The analytical sensitivity and specificity of the rapid test were 100 and 99%, respectively, for unfrozen serum samples (n = 103; 12 PUUV IgM-positive samples). When freeze-thawed serum samples were used, the sensitivity and specificity were each 97.1% (n = 70; 35 PUUV IgM-positive samples). The specificity of the test was 96.2% for 27 serum samples with nonspecific IgM antibodies or rheumatoid factor (RF). The fingertip blood samples (n = 30) were negative, but they gave clear positive results when spiked with IgM-positive sera (n = 20). The results were in good agreement with the standard diagnostic methods. The rapid performance, the lack of need for refined laboratory equipment, and the high specificity with fresh serum and fingertip blood samples indicate that the developed POC PUUMALA rapid test is a useful tool for fast diagnosis of acute PUUV infection

EUS-guided fine needle aspiration of the liver: indications, yield, and safety based on an international survey of 167 cases

Background.-The liver is a common site of metastases for various malignancies. EUS-guided fine needle aspiration (EUS-FNA) of liver masses has only been reported in small series from single centers. Methods: A retrospective questionnaire was sent by e-mail to 130 EUS-FNA centers around the world regarding indications, complications, and findings of EUS-FNA of the liver.Results: Twenty-one centers reported 167 cases of EUS-FNA of the liver. A complication was reported in 6 (4%) of 167 cases including the following: death in 1 patient with an occluding biliary stent and biliary sepsis, bleeding (1), fever (2), and pain (2). EUS-FNA diagnosed malignancy in 23 of 26 (89%) cases after nondiagnostic fine needle aspiration under transabdominal US guidance. EUS localized an unrecognized primary tumor in 17 of 33 (52%) cases in which CT had demonstrated only liver metastases. EUS image characteristics were not predictive of malignant versus benign lesions.Conclusion: EUS-guided FNA of the liver appears to be a safe procedure with a major complication rate of approximately 1%. EUS-FNA should be considered when a liver lesion is poorly accessible to US-, or CT-guided FNA should be considered when US- or CT-guided FNA fail to make a diagnosis, when a liver lesion(s) is detected (de novo) by EUS, and for investigation of possible upper GI primary tumors in the setting of liver metastases.Med Univ S Carolina, Charleston, SC 29425 USAInst J Paoli I Calmettes, F-13009 Marseille, FranceScott & White Mem Hosp & Clin, Temple, TX USAGI Consultants Ltd, Milwaukee, WI USAClin Caracas, Caracas, VenezuelaHennepin Cty Med Ctr, Minneapolis, MN 55415 USAPortland Vet Adm Hosp, Portland, OR USAUniversidade Federal de São Paulo, São Paulo, BrazilUniv Chicago, Chicago, IL 60637 USAUniv Paris 07, Beaujen Hosp, Clichy, FranceHenry Ford Hosp, Detroit, MI 48202 USADuke Univ, Sch Med, Durham, NC USAThomas Jefferson Univ Hosp, Philadelphia, PA 19107 USAMayo Clin, Scottsdale, AZ USAUniv Massachusetts, Med Ctr, Worcester, MA USAAichi Canc Ctr Hosp, Aichi, JapanUniv Hosp Cleveland, Cleveland, OH 44106 USAUniv Maryland, Med Ctr, Baltimore, MD 21201 USAMayo Clin, Jacksonville, FL 32224 USAGentofte Univ Hosp, Hellerup, DenmarkClin Reina Sofia, Bogota, ColombiaUniversidade Federal de São Paulo, São Paulo, BrazilWeb of Scienc