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A new class of crystal shapes has been developed for x-ray spectroscopy of point-like or small (a few mm) emission sources. These optics allow for dramatic improvement in both achievable energy resolution and total throughput of the spectrometer as compared with traditional designs. This class of crystal shapes, collectively referred to as the Variable-Radii Spiral (VR-Spiral), utilize crystal shapes in which both the major and minor radii are variable. A crystal using this novel VR-Spiral shape has now been fabricated for high-resolution Extended X-ray Absorption Fine Structure (EXAFS) experiments targeting the Pb-L3 (13.0 keV) absorption edge at the National Ignition Facility. The performance of this crystal has been characterized in the laboratory using a microfocus x-ray source, showing that high-resolution high-throughput EXAFS spectra can be acquired using this geometry. Importantly, these successful tests show that the complex three-dimensional crystal shape is manufacturable with the required precision needed to realize the expected performance of better than 5 eV energy resolution while using a 30 mm high crystal. An improved generalized mathematical form for VR-Spiral shapes is also presented allowing improved optimization as compared to the first sinusoidal-spiral based design. This new formulation allows VR-Spiral spectrometers to be designed at any magnification with optimized energy resolution at all energies within the spectrometer bandwidth.

A Monte Carlo technique has been developed to simulate the expected signal and the statistical noise of x-ray spectrometers that use streak cameras to achieve the time resolution required for ultrafast diagnostics of laser-generated plasmas. The technique accounts for statistics from both the photons incident on the streak camera’s photocathode and the electrons emitted by the photocathode travelling through the camera’s electron optics to the sensor. We use the technique to optimize the design of a spectrometer, which deduces the temporal history of electron temperature of the hotspot in an inertial confinement fusion implosion from its hard x-ray continuum emission spectra. The technique is general enough to be applied to any instrument using an x-ray streak camera.

BACKGROUND: The surgical treatment for non-tuberculous mycobacterial pulmonary disease (NTM-PD) has an important adjunctive role and reported outcomes have been generally good; however, the prognostic factors remain unclear.METHODS: Sixty-one patients with NTM-PD who underwent surgical resection for a therapeutic purpose from January 2000 to March 2017 at five affiliated institutions were enrolled. We explored the factors that influence complications and prognosis by retrospectively referring to the medical records.RESULTS: The mean age of the present cohort was 61.8 ± 11.4 years. The pathogen was Mycobacterium avium complex in 49 patients, M. abscessus in 5. The most common indications were refractory to medication in 39. The surgical techniques employed were lobectomy or further resection in 49, sublobar resection in 8, with video-assisted thoracoscopic surgery in 21. Sputum culture conversion rate was 95.1%. Univariate analysis of factors associated with deterioration revealed significant differences related to age (P = 0.025), pre-operative albumin level (P = 0.001) and development of postoperative complications (P = 0.037), while pre-operative albumin level alone was a significant factor in multivariate analysis (P = 0.009).CONCLUSION: Outcomes after resection were generally good in the present cases. Nutritional status, as indicated by albumin level, may affect prognosis after surgical treatment.

A novel high-resolution x-ray spectrometer for point-like emission sources has been developed using a crystal shape having both a variable major and a variable minor radius of curvature. This variable-radii sinusoidal spiral spectrometer (VR-Spiral) allows three common spectrometer design goals to be achieved simultaneously: 1. reduction of aberrations and improved spectral (energy) resolution, 2. reduction of source size broadening, and 3. use of large crystals to improve total throughput. The VR-Spiral concept and its application to practical spectrometer design are described in detail. This concept is then used to design a spectrometer for an extreme extended x-ray absorption fine structure experiment at the National Ignition Facility looking at the Pb L3 absorption edge at 13.0352 keV. The expected performance of this VR-Spiral spectrometer, both in terms of energy resolution and spatial resolution, is evaluated through the use of a newly developed raytracing tool, xicsrt. Finally, the expected performance of the VR-Spiral concept is compared to that of spectrometers based on conventional toroidal and variable-radii toroidal crystal geometries showing a greatly improved energy resolution.

This work discusses the development of x-ray and gamma-ray sources based on laser-wakefield acceleration (LWFA) in the self-modulated regime. These sources are developed for probing high energy density (HED) science experiments at large-scale laser facilities.

We report the development of a high-resolution spectrometer for extended x-ray absorption fine structure (EXAFS) studies of materials under extreme conditions. A curved crystal and detector in the spectrometer are replaceable such that a single body is employed to perform EXAFS measurements at different x-ray energy intervals of interest. Two configurations have been implemented using toroidal crystals with Ge 311 reflection set to provide EXAFS at the Cu K-edge (energy range 8.9-9.8 keV) and Ge 400 reflection set to provide EXAFS at the Ta L3-edge (9.8-10.7 keV). Key performance characteristics of the spectrometer were found to be consistent with design parameters. The data generated at the National Ignition Facility have shown an ≃3 eV spectral resolution for the Cu K-edge configuration and ≃6 eV for the Ta L3-edge configuration.

Background In some patients, non-tuberculous mycobacteria (NTM) infections manifest in solitary nodules (solitary nodular [SN] type) generally caused by Mycobacterium avium complex (MAC). In patients treated using surgical resection, the American Thoracic Society guidelines state that postoperative chemotherapy is not necessary in the absence of lesions, although there have been a few reports of such cases. Methods Twenty-eight patients diagnosed with NTM who underwent solitary pulmonary nodule resection at Toneyama Hospital, Osaka, Japan, between January 2000 and October 2012 were enrolled. We evaluated the influence of the surgical procedure and chemotherapy on outcomes in this retrospective study. Results Of the 28 patients, 12 were males and 16 were females; the mean age was 58.6 ± 13.2 years. Twenty-five patients were asymptomatic and bronchoscopy was performed in 18; only 2 had a definitive diagnosis of NTM. The pathogen responsible was MAC in 27 patients and M. kansasii in 1. The surgical procedure used was wedge resection in 22 patients, segmentectomy in 1 and lobectomy in 5. Postoperative chemotherapy was administered to 9 patients. Twenty-six patients had no recurrence. Conclusion We believe that wedge resection is a valid surgical intervention for SN type NTM; additional postoperative chemotherapy is unnecessary in cases with no residual lesions in the operated lung lobe.