New Options for Soybean Aphid Host Plant Resistance

Host plant resistance for soybean aphid is the newest management tool for yield protection. In 2010, a single gene expression, called Rag1, was commercially released in the north central region. Aphids feeding on Rag1 plants do not live as long or produce as many offspring compared to when they feed on susceptible plants. In small plot evaluations of the Rag1 gene, there is a dramatic decrease in the seasonal accumulation of soybean aphid compared to aphids developing on susceptible varieties

LCLS X-ray mirror measurements using a large aperture visible light interferometer

Synchrotron or FEL X-ray mirrors are required to deliver an X-ray beam from its source to an experiment location, without contributing significantly to wave front distortion. Accurate mirror figure measurements are required prior to installation to meet this intent. This paper describes how a 300 mm aperture phasing interferometer was calibrated to <1 nm absolute accuracy and used to mount and measure 450 mm long flats for the Linear Coherent Light Source (LCLS) at Stanford Linear Accelerator Center. Measuring focus mirrors with an interferometer requires additional calibration, because high fringe density introduces systematic errors from the interferometer's imaging optics. This paper describes how these errors can be measured and corrected. The calibration approaches described here apply equally well to interferometers larger than 300 mm aperture, which are becoming more common in optics laboratories. The objective of this effort was to install LCLS flats with < 10 nm of spherical curvature, and < 2 nm rms a-sphere. The objective was met by measuring the mirrors after fabrication, coating and mounting, using a 300 mm aperture phasing interferometer calibrated to an accuracy < 1 nm. The key to calibrating the interferometer accurately was to sample the error using independent geometries that are available. The results of those measurements helped identify and reduce calibration error sources. The approach used to measure flats applies equally well to focus mirrors, provided an additional calibration is performed to measure the error introduced by fringe density. This calibration has been performed on the 300 mm aperture interferometer, and the measurement correction was evaluated for a typical focus mirror. The 300 mm aperture limitation requires stitching figure measurements together for many X-ray mirrors of interest, introducing another possible error source. Stitching is eliminated by applying the calibrations described above to larger aperture instruments. The authors are presently extending this work to a 600 mm instrument. Instruments with 900 mm aperture are now becoming available, which would accommodate the largest mirrors of interest

The CUL1 C-Terminal Sequence and ROC1 Are Required for Efficient Nuclear Accumulation, NEDD8 Modification, and Ubiquitin Ligase Activity of CUL1

Members of the cullin and RING finger ROC protein families form heterodimeric complexes to constitute a potentially large number of distinct E3 ubiquitin ligases. We report here that the highly conserved C-terminal sequence in CUL1 is dually required, both for nuclear localization and for modification by NEDD8. Disruption of ROC1 binding impaired nuclear accumulation of CUL1 and decreased NEDD8 modification in vivo but had no effect on NEDD8 modification of CUL1 in vitro, suggesting that ROC1 promotes CUL1 nuclear accumulation to facilitate its NEDD8 modification. Disruption of NEDD8 binding had no effect on ROC1 binding, nor did it affect nuclear localization of CUL1, suggesting that nuclear localization and NEDD8 modification of CUL1 are two separable steps, with nuclear import preceding and required for NEDD8 modification. Disrupting NEDD8 modification diminishes the IκBα ubiquitin ligase activity of CUL1. These results identify a pathway for regulation of CUL1 activity—ROC1 and the CUL1 C-terminal sequence collaboratively mediate nuclear accumulation and NEDD8 modification, facilitating assembly of active CUL1 ubiquitin ligase. This pathway may be commonly utilized for the assembly of other cullin ligases

Unusual association of alveolar rhabdomyosarcoma with pancreatic metastasis: emerging role of PET-CT in tumor staging

Pancreatic metastases in childhood cancer have been rarely reported in the radiology literature although ample evidence exists in pathology reports for its occurrence in patients with alveolar rhabdomyosarcomas (RMS). Assess the occurrence of pancreatic metastases in alveolar rhabdomyosarcomas, increase awareness of this association and reassess current staging protocols. Three major oncology centers reviewed their records and imaging examinations. Patients’ history and demographics, primary tumor site and histology, presence of tumor recurrence, and presence and location of other metastases were reviewed. Pancreatic metastases occurred in eight patients with alveolar RMS. Four of these presented at diagnosis and four with disease recurrence. In recurrent disease, the duration between the diagnosis of the primary tumor and pancreatic metastases varied from 8 months to 6 years (mean ± SD: 2.38 ± 2.49 years). In all patients who received PET scans, pancreatic metastases showed a marked FDG-uptake, but had variable detectability with CT. Pancreatic metastases were not associated with certain primary tumor locations or presence of other metastases, mandating an evaluation of the pancreas in all cases of alveolar rhabdomyosarcomas. Radiologists should be sensitized and actively evaluate the pancreas in patients with alveolar RMS. Optimizing CT and PET-CT protocols may increase the diagnostic yield

Soft X-ray Mirrors for the Linac Coherent Light Source

The Linac Coherent Light Source (LCLS) is a 0.15-1.5 nm wavelength free-electron laser (FEL) being constructed at the Stanford Linear Accelerator Center (SLAC) by a multi-institution consortium, including Lawrence Livermore National Laboratory (LLNL). One of LLNL's responsibilities involves the design and construction of two grazing-incidence mirror systems whose primary intent is to reduce radiation levels in the experimental halls by separating the FEL beam from unwanted high-energy photons. This paper discusses one of these systems, the Soft X-ray Offset Mirror System (SOMS) that will operate in the wavelength range 0.62-1.5 nm (0.827-2.00 keV). The unusual properties of the FEL beam translate to stringent specifications in terms of stability, material choice and mirror properties. It also precludes using approaches previously developed for synchrotron light sources. This situation has led us to a unique mirror design, consisting of a reflective boron carbide layer deposited on a silicon substrate. In the first part of this paper, we discuss the basic system requirements for the SOMS and motivate the need for these novel reflective elements. In the second part of this paper, we discuss the development work we have performed, including simulation and experimental verification of the boron carbide coating properties, and the expected performance of the final system

Opposed port alignment system (OPAS): a commercial astronomical telescope modified for viewing the interior of the NIF target chamber

Abstract not provide

A broadband high-resolution elliptical crystal x-ray spectrometer for high energy density physics experiments

Spectroscopic investigation of high temperature laser produced plasmas in general, and x-ray opacity experiments in particular, often requires instruments with both a broad coverage of x-ray energies and high spectral, spatial, and temporal resolution. We analyze the design, model the response, and report the commissioning of a spectrometer using elliptical crystals in conjunction with a large format, gated microchannel plate detector. Measurements taken with this instrument at the JANUS laser facilities demonstrate the designed spectral range of 0.24 to 5.8 keV, and spectral resolution E/{Delta}E > 500, resulting in 2 to 3 times more spectral data than achieved by previous spectrometer designs. The observed 100 picosecond temporal resolution and 35 {micro}m spatial resolution are consistent with the requirements of high energy density opacity experiments

A compact UV timing fiducial system for use with x-ray streak cameras at NIF

Abstract not provide

Preparing Students to Work in Diverse Settings and Across Distance: Inter-University, Interdisciplinary Capstone Teams

NASA's Psyche Mission is engaged with a growing number of capstone teams pursuing topics relevant to the mission, including partnering with four universities to trial cross-university teaming. Creating interdisciplinary capstone teams with students from different universities provides an opportunity to prepare students to engage with a diversity of disciplines and collaborate in remote teams in the workplace. Additionally, through such capstones, universities may gain access to non-local, specialized technical mentors and to disciplines not offered at their institutions. An added benefit is providing greater fidelity to NASA space missions, which involve teams working together at a distance. We discuss early lessons learned from the first three inter-university, interdisciplinary capstone teams participating with the Psyche mission and discuss plans for improvement and future expansion