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Pinhole imaging of the neutron production in laser-driven inertial confinement fusion experiments can provide important information about the performance of various capsule designs. This requires the development of systems capable of spatial resolutions on the order of 5 μm or less for source strengths of 1015 and greater. We have initiated a program which will lead to the achievement of such a system to be employed at the National Ignition Facility (NIF) facility. Calculated neutron output distributions for various capsule designs will be presented to illustrate the information which can be gained from neutron imaging and to demonstrate the requirements for a useful system. We will describe the lines-of-sight available at NIF for neutron imaging and explain how these can be utilized to reach the required parameters for neutron imaging. We will describe initial development work to be carried out at the Omega facility and the path which will lead to systems to be implemented at NIF. Beginning this year, preliminary experiments will be aimed at achieving resolutions of 30–60 μm for direct-drive capsules with neutron outputs of about 1014. The main thrust of these experiments will be to understand issues related to the fabrication and alignment of small diameter pinhole systems as well as the problems associated with signal-to-background ratios at the image plane. Subsequent experiments at Omega will be described. These efforts will be aimed at achieving resolutions of about 10 μm. Proposed developments for new imaging systems as well as further refinement of pinhole techniques will be presented.

It is shown that regions of enhanced pressure have been produced in targets with indirect radiation drive in planar and cylindrically convergent geometry through the interaction between the flows caused by target inhomogeneities and the main target drive. Design calculations for National Ignition Facility (NIF) [J. A. Paisner et al., Laser Focus World 30, 75 (1994)] targets with beryllium ablators formed by bonded hemi-shells [D. C. Wilson et al., Bull. Am. Phys. Soc. 43, 1667 (1998)] indicate that related behavior produces a seed perturbation in the ablator which can in some cases lead to the suppression of ignition. From simulation and analysis of the NIF problem in the planar geometry analog, a scaling for the perturbation, which should be useful for validation of the behavior with lower energy drive and smaller-scale geometries, is derived.

The use of copper-doped beryllium ablators on National Ignition Facility [J. A. Paisner et al., Laser Focus World 30, 75 (1994)] targets, in place of plastic, can require the bonding together of hemispheres with a joint of differing composition. Indirect drive experiments have been conducted on the Nova laser [J. L. Emmet, W. F. Krupke, and J. B. Trenholme, Sov. J. Quantum Electron. 13, 1 (1983)], and the resulting shock structuring compared with code simulations. It is concluded that one of the available codes, the RAGE code [R. M. Baltrusaitis et al., Phys. Fluids 8, 2471 (1996)] provides useful insight into the effect of joints. This code is then employed to obtain a physical picture of the shock front nonuniformity in terms of a secondary rarefaction and an oblique shock interacting with the main shock that propagates in the absence of the joint. A simple analysis reinforces this picture.

How can physicians motivate patients with alcohol problems when they resist advice to change? A framework for understanding patient resistance is described to help physicians use this motivational approach more effectively with patients.

Several inertial confinement fusion (ICF) capsule designs have been proposed as possible candidates for achieving ignition by indirect drive on the National Ignition Facility (NIF) laser [Paisner et al., Laser Focus World 30, 75 (1994)]. This article reviews these designs, their predicted performance using one-, two-, and three-dimensional numerical simulations, and their fabricability. Recent design work at a peak x-ray drive temperature of 250 eV with either 900 or 1300 kJ total laser energy confirms earlier capsule performance estimates [Lindl, Phys. Plasmas 2, 3933 (1995)] that were based on hydrodynamic stability arguments. These simulations at 250 eV and others at the nominal 300 eV drive show that capsules having either copper doped beryllium (Be+Cu) or polyimide (C22H10N2O4) ablators have favorable implosion stability and material fabrication properties. Prototypes of capsules using these ablator materials are being constructed using several techniques: brazing together machined hemishells (Be+Cu), sputter deposition (Be+Cu), and monomer deposition followed by thermal processing (polyimide).

Several choices exist in the design and production of capsules intended to ignite and propagate fusion burn of the deuterium–tritium (D–T) fuel when imploded by indirect drive at the National Ignition Facility (NIF). These choices include ablator material, ablator dopant concentration and distribution, capsule dimensions, and X-ray drive profile (shock timings and strengths). The choice of ablator material must also include fabrication and material characteristics, such as attainable surface finishes, permeability, strength, transparency to radio frequency and infrared radiation, thermal conductivity, and material homogeneity. Understanding the advantages and/or limitations of these choices is an ongoing effort for LLNL and LANL designers. At this time, simulations in one-, two-, and three-dimensions show that capsules with either a copper-doped beryllium or a polyimide (C22H10N2O4) ablator material have both the least sensitivity to initial surface roughnesses and favorable fabrication qualities. Simulations also indicate the existence of capsule designs based on these ablator materials which ignite and burn when imploded by less than nominal laser performance (900-kJ energy, 250-TW power, producing 250-eV peak radiation temperature). We will describe and compare these reduced-scale capsules, in addition to several designs which use the expected 300-eV peak X-ray drive obtained from operating the NIF laser at 1.3 MJ and 500 TW.

Prenatal screening for chromosomal abnormalities is a rapidly changing field. Increasing emphasis is being placed on the development of non-invasive screening methods based on maternal biochemical markers and ultrasound findings. The purpose of this article is to provide the clinician with an update on these newer methods, and to discuss their advantages and disadvantages when compared with our current standard of care (maternal age-based screening). In addition, the clinical implications of introducing such screening on a large-scale basis are discussed.

Recent experiments have shown that low density foam layers can significantly mitigate the perturbing effects of beam nonuniformities affecting the acceleration of thin shells. This problem is studied parametrically with two-dimensional LASNEX [G. B. Zimmerman and W. L. Kruer, Comments Plasma Phys. Controlled Fusion 2, 51 (1975)]. Foam-buffered targets are employed, consisting typically of 250 A of gold, and 50 μm of 50 mg/cm3 C10H8O4 foam attached to a 10 μm foil. In simulation these were characteristically exposed to 1.2 ns, flat-topped green light pulses at 1.4×1014 W/cm2 intensity, bearing 30 μm lateral perturbations of up to 60% variation in intensity. Without the buffer layers the foils were severely disrupted by 1 ns. With buffering only minimal distortion was manifest at 3 ns. The smoothing is shown to derive principally from the high thermal conductivity of the heated foam. The simulation results imply that (1) the foam thickness should exceed the disturbance wavelength; (2) intensities exceeding ...

Two World Ocean Circulation Experiment hydrographic cruises in March and June 1995, along with Topex- Poseidon altimeter data and National Meteorological Center wind data are used to estimate seasonal changes in the South Indian Ocean subtropical gyre. Mean annual curves derived from the altimeter and wind data reveal strengthening of the anticyclonic gyre in March and September, and weakening in June and December. The seasonal changes correspond to variations in the wind field south of 30 oS at the equinoxes and solstices. In addition, the wind-driven gyre is further north in July, and further south in March. These variations in strength and location of the South Indian Ocean gyre may influence inter-ocean transports south of Africa. Despite the inferred mean annual seasonal variations in the South Indian Ocean gyre, volume transports estimated in 1995 from the hydrographic data are close to mean values. Apparently, a mesoscale eddy in March disrupts the stronger fall gyre, whereas in June the weaker winter gyre is

Structure-activity relationships of a lead hydroxamic acid inhibitor of recombinant human stromelysin were systematically defined by taking advantage of a concise synthesis that allowed diverse functionality to be explored at each position in a template. An ex vivo rat model and an in vivo rabbit model of stromelysin-induced cartilage degradation were used to further optimize these analogs for oral activity and duration of action. The culmination of these modifications resulted in CGS 27023A, a potent, orally active stromelysin inhibitor that blocks the erosion of cartilage matrix.

Creation of a low density, high temperature plasma buffer between the absorption and ablation layers of a directly driven inertial confinement fusion implosion capsule has been proposed as a means to reduce “early time” imprint from laser nonuniformities. This thermal smoothing blanket might be created from a low density foam layer wrapped around the deuterium–tritium filled microballoon. Preliminary spherical implosion tests of this concept using a polystyrene foam layer surrounding a glass microballoon were performed at the Nova laser [Rev. Sci. Instrum. 57, 2101 (1986)], using a 527 nm drive wavelength. Comparison of capsule yield and imploded core symmetry showed promising improvements in overall target performance, relative to one-dimensional undegraded hydrodynamic simulations, when the foam-buffer layer was present.

Directly laser driven and X-radiation driven DT filled capsules differ in the relationship between neutron and X-ray images. Shot N110217, a directly driven DT-filled glass micro-balloon provided the first neutron images at the National Ignition Facility. As seen in implosions on the Omega laser, the neutron image can be enclosed inside time integrated X-ray images. HYDRA simulations show the X-ray image is dominated by emission from the hot glass shell while the neutron image arises from the DT fuel it encloses. In the absence of mix or jetting, X-ray images of a cryogenically layered THD fuel capsule should be dominated by emission from the hydrogen rather than the cooler plastic shell that is separated from the hot core by cold DT fuel. This cool, dense DT, invisible in X-ray emission, shows itself by scattering hot core neutrons. Germanium X-ray emission spectra and Ross pair filtered X-ray energy resolved images suggest that germanium doped plastic emits in the torus shaped hot spot, probably reducing the neutron yield.

In most conflicts there is the potential that there will be Captured Persons (CPERS) whose medical care is the responsibility of the capturing army. The standard of this care should be to the same standard as that afforded to one9s own troops. However the medical practicalities of maintaining such standards can be difficult. This article reviews the practicalities of the medical care of CPERS as part of the UK deployment in Afghanistan on Operation HERRICK.

We present the first results from an experimental campaign to measure the atomic ablator-gas mix in the deceleration phase of gas-filled capsule implosions on the National Ignition Facility. Plastic capsules containing CD layers were filled with tritium gas; as the reactants are initially separated, DT fusion yield provides a direct measure of the atomic mix of ablator into the hot spot gas. Capsules were imploded with x rays generated in hohlraums with peak radiation temperatures of ∼294 eV. While the TT fusion reaction probes conditions in the central part (core) of the implosion hot spot, the DT reaction probes a mixed region on the outer part of the hot spot near the ablator-hot-spot interface. Experimental data were used to develop and validate the atomic-mix model used in two-dimensional simulations.

Los Alamos National Laboratory is contributing to the core science and technology of the inertial confinement fusion program leading to the National Ignition Facility. Short summaries of a sample o...

Neutron imaging provides a powerful diagnostic for understanding the performance of inertial confinement fusion ignition capsules and the drive mechanism imploding them. To achieve the spatial resolution and fielding capability needed at the National Ignition Facility requires a staged approach that simultaneously pushes the limits of extant capabilities while developing new techniques that will extend to the National Ignition Facility regime. To this end, new pinhole assemblies have been designed and fabricated using very high-precision machining equipment. These assemblies have been fielded successfully at Laboratory for Laser Energetics, University of Rochester and have provided impetus for new aperture designs and new ideas for detectors, which are now the limiting element in the system resolution.

Good radiation drive symmetry will be crucial for achieving ignition in laboratory inertial fusion experiments. The indirect‐drive inertial confinement fusion (ICF) method utilizes the soft x‐ray field in a radiation‐containing cavity, or hohlraum, to help achieve a high degree of symmetry. Achievement of the conditions necessary for ignition and gain will require experimental fine tuning of the drive symmetry. In order to make tuning possible, a significant effort has been devoted to developing symmetry measurement techniques. These techniques have been applied to a series of experiments that give a graphic picture of the symmetry conditions in the complex hohlraum environment. These experiments have been compared with detailed, fully integrated theoretical modeling. The ultimate goal of this work is the detailed understanding of symmetry conditions and the methods for their control. Comparison with experiments provides crucial benchmarking for the modeling—a key element in planning for ignition.

Introduction: RET/PTC1 was one of the first gene fusions identified from a solid tumor. In the past 3 years, oncogenic RET fusions have been identified in additional cancer types, most notably NSCLC and colon carcinomas. Activating germline RET mutations are also well established drivers of multiple endocrine neoplasia while somatic RET mutations are the most prevalent alterations in sporadic medullary thyroid cancers. In light of these findings, a number of approved multi-kinase inhibitors (mKIs) with in vitro activity against wild-type (WT) RET, such as cabozantinib, vandetanib, and lenvatinib, have been repurposed for treating RET-driven diseases. We have designed a next-generation inhibitor specifically tailored to target RET, while sparing other closely-related kinases, such as KDR/VEGFR2. Given that secondary mutations are a common resistance mechanism to kinase inhibitors, we prospectively identified resistance mutations that abrogate mKI activity and crafted our RET-selective inhibitors to also target these mutations. The structures of several mKIs bound to RET were analyzed and amino acid substitutions that would disrupt the protein-inhibitor interactions were predicted. In vitro resistance screens with cabozantinib, ponatinib, and vandetanib in a Ba/F3 KIF5B-RET cell line were conducted and confirmed these predictions. The proprietary Blueprint Medicines’ kinase inhibitor library was used to identify inhibitors of WT and resistance mutant RET as starting points for lead optimization. Results: Both structural analysis and in vitro screening revealed that only a handful of positions within the RET kinase domain enable resistance mutations to mKIs, suggesting a narrow mutational spectrum. Using our library of kinase inhibitors, we identified potent, orally bioavailable inhibitors of RET that target both the WT and resistance mutants in KIF5B-RET-driven cell lines while sparing the majority of the kinome. These inhibitors also suppressed the proliferation of thyroid cancer cell lines harboring RET fusions or activating RET mutations and demonstrated in vivo activity in xenograft models. Our analysis of the PK-PD-efficacy relationship revealed that over 70% target suppression is required for maximal efficacy. Finally, our RET-selective inhibitors induced dose-dependent tumor growth inhibition in a KIF5B-RET fusion positive lung adenocarcinoma PDX model at well-tolerated doses, further validating RET fusions as oncogenic drivers in NSCLC. Conclusion: This work describes the identification of potent inhibitors that specifically target WT RET and resistance mutations predicted to arise upon mKI treatment. By sparing kinases with known toxicity profiles, these molecules are predicted to robustly inhibit RET at tolerated doses and may provide patients with RET-driven diseases an opportunity for more durable and effective therapies. Citation Format: Rami Rahal, Erica K. Evans, Wei Hu, Michelle Maynard, Paul Fleming, Lucian DiPietro, Joseph L. Kim, Michael P. Sheets, Doug P. Wilson, Kevin J. Wilson, Nicolas Stransky, Jason D. Brubaker, Timothy Guzi, Nancy E. Kohl, Christoph Lengauer. The development of potent, selective RET inhibitors that target both wild-type RET and prospectively identified resistance mutations to multi-kinase inhibitors. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 2641.

National Ignition Facility experiments with beryllium capsules have followed a path begun with "high-foot" plastic capsule implosions. Three shock timing keyhole targets, one symmetry capsule, a streaked backlit capsule, and a 2D backlit capsule were fielded before the DT layered shot. After backscatter subtraction, laser drive degradation is needed to match observed X-ray drives. VISAR measurements determined drive degradation for the picket, trough, and second pulse. Time dependence of the total Dante flux reflects degradation of the of the third laser pulse. The same drive degradation that matches Dante data for three beryllium shots matches Dante and bangtimes for plastic shots N130501 and N130812. In the picket of both Be and CH hohlraums, calculations over-estimate the x-ray flux > 1.8 keV by ~100X, while calculating the total flux correctly. In beryllium calculations these X-rays cause an early expansion of the beryllium/fuel interface at ~3 km/s. VISAR measurements gave only ~0.3 km/s. The X-ray drive on the Be DT capsule was further degraded by an unplanned decrease of 9% in the total picket flux. This small change caused the fuel adiabat to rise from 1.8 to 2.3. The first NIF beryllium DT implosion achieved 29% of calculated yield, compared to CH capsules with 68% and 21%.

The first indirect drive implosion experiments using Beryllium (Be) capsules at the National Ignition Facility confirm the superior ablation properties and elucidate possible Be-ablator issues such as hohlraum filling by ablator material. Since the 1990s, Be has been the preferred Inertial Confinement Fusion (ICF) ablator because of its higher mass ablation rate compared to that of carbon-based ablators. This enables ICF target designs with higher implosion velocities at lower radiation temperatures and improved hydrodynamic stability through greater ablative stabilization. Recent experiments to demonstrate the viability of Be ablator target designs measured the backscattered laser energy, capsule implosion velocity, core implosion shape from self-emission, and in-flight capsule shape from backlit imaging. The laser backscatter is similar to that from comparable plastic (CH) targets under the same hohlraum conditions. Implosion velocity measurements from backlit streaked radiography show that laser energy coupling to the hohlraum wall is comparable to plastic ablators. The measured implosion shape indicates no significant reduction of laser energy from the inner laser cone beams reaching the hohlraum wall as compared with plastic and high-density carbon ablators. These results indicate that the high mass ablation rate for beryllium capsules does not significantly alter hohlraum energetics. In addition, these data, together with data for low fill-density hohlraum performance, indicate that laser power multipliers, required to reconcile simulations with experimental observations, are likely due to our limited understanding of the hohlraum rather than the capsule physics since similar multipliers are needed for both Be and CH capsules as seen in experiments.

We present results of the beryllium experimental campaign on the implosion symmetry properties of beryllium capsules at the National Ignition Facility (NIF) [1]. These indirect drive experiments measure both the inflight and core self-emission implosion symmetry. The inflight symmetry of the ablator before stagnation is measured using a backlight imaging technique. A copper backlighter was used to measure the transmissions (or backlit absorption) of the copper doped beryllium shells. Images of the x-ray emission from the core around bang time provide a measure of the symmetry near peak compression. Both pieces of information about the 2D symmetry are used to infer the drive and velocity uniformity enabling us to predictably adjust the properties of the incident laser, mainly the time dependent ratio of the inner beam cone power to the outer laser beam powers, to achieve proper symmetry of the implosion. Results from these experiments show inner beam propagation is not degraded compared to similar implosions with CH ablators. Variations in the shape compared with implosions using CH ablators also provides information about the cross beam energy transfer used to adjust the equatorial shape and thus infer information about the differences in plasma conditions near the laser entrance holes. Experimental results of the implosion shape for beryllium capsules will be presented along with comparisons relative to CH ablators.

During the (boreal) spring and fall of 1992 the NOAA Ocean-Atmosphere Carbon Exchange Study did an intensive survey of upper water column (⪡1000 m) chemistry in the eastern equatorial Pacific from 110°W to 170°W. The spring-time conditions were influenced by an El Nino that had disappeared before the fall cruises. This contributed to a large seasonal contrast in surface temperature, carbon and nutrient concentrations, and thermocline depth. Nitrate, total inorganic carbon, and fugacity of CO 2 values were significantly lower in the spring, while sea surface temperatures south of the equator were higher. The seasonal change in surface water chemistry at the equator is due to changes in upwelling of nutrient and carbon enriched water. Oxygen and CO 2 anomalies at the surface point to approximately a three-fold increase in upwelling of thermocline water in the fall compared to the spring. The large-scale spatial variations in the surface chemistry patterns remained unchanged between spring and fall. There was a westward decrease in surfacewater carbon and nitrate concentrations and a strong north to south asymmetry with higher carbon and nitrate values south of the equator. This pattern is attributed to input of carbon and nutrients with the South Equatorial Current from the east. Using velocities obtained from surface drifters tracks, along with reasonable gas exchange estimates, and a “Redfield analysis” to account for export biological production, this westward decrease in carbon and nutrients can be quantitatively accounted for in the region from 0 to 3°S and 110°W to 140°W in the spring. In the fall the calculated concentration decrease is greater than observed, which is attributed to input from local equatorial upwelling along the pathway of water transit.

The National Ignition Facility has been used to compress deuterium-tritium to an average areal density of ~1.0±0.1 g cm(-2), which is 67% of the ignition requirement. These conditions were obtained using 192 laser beams with total energy of 1-1.6 MJ and peak power up to 420 TW to create a hohlraum drive with a shaped power profile, peaking at a soft x-ray radiation temperature of 275-300 eV. This pulse delivered a series of shocks that compressed a capsule containing cryogenic deuterium-tritium to a radius of 25-35 μm. Neutron images of the implosion were used to estimate a fuel density of 500-800 g cm(-3).

A new class of silicone matrix-based composites has been developed, particularly for use in the thermal protection of missile launch structures. In this application. screening tests have shown that these materials, coded SM8000, offer three-fold performance improvement over conventional phenolic-based composites. Initial investigations designed to identify commercial opportunities for the material have also met with some success. Promising applications as diverse as commercial jet-engine fire shields and high-temperature automotive gaskets have illustrated the potential widespread use of this type of material. This paper will examine the development, properties and applications of these silicone matrix composites.

A team headed by LANL and including many members from LLNL and NSTec LO and NSTec LAO fielded a neutron imaging system (NIS) at the National Ignition Facility at the start of 2011. The NIS consists of a pinhole array that is located 32.5 cm from the source and that creates an image of the source in a segmented scintillator 28 m from the source. The scintillator is viewed by two gated, optical imaging systems: one that is fiber coupled, and one that is lens coupled. While there are a number of other pieces to the system related to pinhole alignment, collimation, shielding and data acquisition, those pieces are discussed elsewhere and are not relevant here. The system is operational and has successfully obtained data on more that ten imaging shots. This remainder of this whitepaper is divided in five main sections. In Section II, we identify three critical areas of improvement that we believe should be pursued to improve the performance of the system for future experiments: spatial resolution, temporal response and signal-to-noise ratio. In Section III, we discuss technologies that could be used to improve these critical performance areas. In Section IV, we describe a path to evolve the current system to achieve improved performance with minimal impact on the ability of the system to operate on shots. In Section V, we discuss the abilities, scope and timescales of the current teams and the Commissariat energie atomique (CEA). In Section VI, we summarize and make specific recommendations for collaboration on improvements to the NIS.

Polyimide matrix composites possess an excellent balance of physical and thermal properties. However, currently available systems suffer from a number of drawbacks. Much of R & D is aimed at overcoming these drawbacks and developing new and novel polyimide materials. This review paper will examine recent developments in polyimide composites in the areas of thermo-oxidative stability, resistance to microcracking, toughness, toxicity and processability.

Generation of debris from targets and by x-ray ablation of surrounding materials will be a matter of concern for experimenters and National Ignition Facility (NIF) operations. Target chamber and final optics protection, for example debris shield damage, drive the interest for NIF operations. Experimenters are primarily concerned with diagnostic survivability, separation of mechanical versus radiation induced test object response in the case of effects tests, and radiation transport through the debris field when the net radiation output is used to benchmark computer codes. In addition, radiochemical analysis of activated capsule debris during ignition shots can provide a measure of the ablator 〈ρr〉. Conceptual design of the Debris Monitor and Rad-Chem Station, one of the NIF core diagnostics, is presented. Methods of debris collection, particle size and mass analysis, impulse measurement, and radiochemical analysis are given. A description of recent experiments involving debris collection and impulse measu...

The gamma reaction history (GRH) diagnostic is a multichannel, time-resolved, energy-thresholded γ-ray spectrometer that provides a high-bandwidth, direct-measurement of fusion reaction history in inertial confinement fusion implosion experiments. 16.75 MeV deuterium+tritium (DT) fusion γ-rays, with a branching ratio of the order of 10(-5)γ/(14 MeV n), are detected to determine fundamental burn parameters, such as nuclear bang time and burn width, critical to achieving ignition at the National Ignition Facility. During the tritium/hydrogen/deuterium ignition tuning campaign, an additional γ-ray line at 19.8 MeV, produced by hydrogen+tritium fusion with a branching ratio of unity, will increase the available γ-ray signal and may allow measurement of reacting fuel composition or ion temperature. Ablator areal density measurements with the GRH are also made possible by detection of 4.43 MeV γ-rays produced by inelastic scatter of DT fusion neutrons on (12)C nuclei in the ablating plastic capsule material.

Development of analysis techniques for neutron imaging at the National Ignition Facility is an important and difficult task for the detailed understanding of high-neutron yield inertial confinement fusion implosions. Once developed, these methods must provide accurate images of the hot and cold fuels so that information about the implosion, such as symmetry and areal density, can be extracted. One method under development involves the numerical inversion of the pinhole image using knowledge of neutron transport through the pinhole aperture from Monte Carlo simulations. In this article we present results of source reconstructions based on simulated images that test the methods effectiveness with regard to pinhole misalignment.

Numerical modeling of the neutron imaging system for the National Ignition Facility (NIF), forward from calculated target neutron emission to a camera image, will guide both the reduction of data and the future development of the system. Located 28 m from target chamber center, the system can produce two images at different neutron energies by gating on neutron arrival time. The brighter image, using neutrons near 14 MeV, reflects the size and symmetry of the implosion "hot spot." A second image in scattered neutrons, 10-12 MeV, reflects the size and symmetry of colder, denser fuel, but with only ∼1%-7% of the neutrons. A misalignment of the pinhole assembly up to ±175 μm is covered by a set of 37 subapertures with different pointings. The model includes the variability of the pinhole point spread function across the field of view. Omega experiments provided absolute calibration, scintillator spatial broadening, and the level of residual light in the down-scattered image from the primary neutrons. Application of the model to light decay measurements of EJ399, BC422, BCF99-55, Xylene, DPAC-30, and Liquid A suggests that DPAC-30 and Liquid A would be preferred over the BCF99-55 scintillator chosen for the first NIF system, if they could be fabricated into detectors with sufficient resolution.

SUMMARY We apply a viscoelastic cycle model to a compilation of GPS velocity fields in order to address the kinematics of deformation in the northwestern United States. A viscoelastic cycle model accounts for time-dependent deformation following large crustal earthquakes and is an alternative to block models for explaining the interseismic crustal velocity field. Building on the approach taken in Pollitz et al., we construct a deformation model for the entire western United States—based on combined fault slip and distributed deformation—and focus on the implications for the Mendocino triple junction (MTJ), Cascadia megathrust, and western Washington. We find significant partitioning between strike-slip and dip-slip motion near the MTJ as the tectonic environment shifts from northwest-directed shear along the San Andreas fault system to east–west convergence along the Juan de Fuca Plate. By better accounting for the budget of aseismic and seismic slip along the Cascadia subduction interface in conjunction with an assumed rheology, we revise a previous model of slip for the M∼ 9 1700 Cascadia earthquake. In western Washington, we infer slip rates on a number of strike-slip and dip-slip faults that accommodate northward convergence of the Oregon Coast block and northwestward convergence of the Juan de Fuca Plate. Lateral variations in first order mechanical properties (e.g. mantle viscosity, vertically averaged rigidity) explain, to a large extent, crustal strain that cannot be rationalized with cyclic deformation on a laterally homogeneous viscoelastic structure. Our analysis also shows that present crustal deformation measurements, particularly with the addition of the Plate Boundary Observatory, can constrain such lateral variations.

SeaMARC II and Sea Beam bathymetric data are combined to create a chart of the East Pacific Rise (EPR) from 8°N to 18°N reaching at least 1 Ma onto the rise flanks in most places. Based on these data as well as SeaMARC II side scan sonar mosaics we offer the following observations and conclusions. The EPR is segmented by ridge axis discontinuities such that the average segment lengths in the area are 360 km for first-order segments, 140 km for second-order segments, 52 km for third-order segments, and 13 km for fourth-order segments. All three first-order discontinuities are transform faults. Where the rise axis is a bathymetric high, second-order discontinuities are overlapping spreading centers (OSCs), usually with a distinctive 3:1 overlap to offset ratio. The off-axis discordant zones created by the OSCs are V-shaped in plan view indicating along axis migration at rates of 40–100 mm yr−1. The discordant zones consist of discrete abandoned ridge tips and overlap basins within a broad wake of anomalously deep bathymetry and high crustal magnetization. The discordant zones indicate that OSCs have commenced at different times and have migrated in different directions. This rules out any linkage between OSCs and a hot spot reference frame. The spacing of abandoned ridges indicates a recurrence interval for ridge abandonment of 20,000–200,000 yrs for OSCs with an average interval of approximately 100,000 yrs. Where the rise axis is a bathymetric low, the only second-order discontinuity mapped is a right-stepping jog in the axial rift valley. The discordant zone consists of a V-shaped wake of elongated deeps and interlocking ridges, similar to the wakes of second-order discontinuities on slow-spreading ridges. At the second-order segment level, long segments tend to lengthen at the expense of neighboring shorter segments. This can be understood if segments can be approximated by cracks, because the propagation force at a crack tip is directly proportional to crack length.

The Chesapeake Bay Interpretive Buoy System (CBIBS) is an innovative system to collect, transmit and interpret real-time environmental data from the Chesapeake Bay to a wide variety of constituents — including scientists, on-the-water users, educators, and natural resource decision-makers — and to fill critical observational gaps in the Chesapeake Bay. The first buoy was deployed in May 2007, and as of October 2009, the CBIBS has expanded to eight buoys. Locations span the length of the bay, from the Susquehanna River to Norfolk, and include open water and tributaries. In addition to collecting environmental information, the System supports educational and informational tools to interpret the Captain John Smith Chesapeake National Historic Trail.

We will present results for the x-ray production from the irradiation and interaction of a 25 ps, 1-Kj, 1ω laser with a thin Iron target. The conversion efficiency to x-rays, the spectrum as well as the time history will be presented. The usefulness of such an x-ray source for backlighting imploded capsules will also be presented and discussed.

Several aerospace companies are actively pursuing the development of a 'high speed civil transport aircraft' (HSCT). Flight profiles and weight considerations dictate the use of high temperature advanced composites. This paper briefly examines two such contenders-PMR-15 and bismaleimides (BMIs). Materials are compared in the categories of thermo-oxidative stability, resistance to thermal cycling, damage tolerance, toxicity and ease of fabrication. At present, it would appear that neither PMR-15 nor BMIs, in general, are capable of meeting HSCT requirements. PMR-15 seems to be hampered by its susceptibility to microcracking, monomer toxicity and difficult fabrication. On the other hand, the use of BMIs seems to be hampered by their relatively poor thermo-oxidative stability. These views assume an aircraft with a maximum operating temperature of about 350°F. Should this requirement change, then the picture will change also and other materials could be considered.

A neutron spectrometer, called a magnetic recoil spectrometer (MRS), has been built and implemented at the OMEGA laser facility [T. R. Boehly et al., Opt. Commun. 133, 495 (1997)] for absolute measurements of the neutron spectrum in the range of 6-30 MeV, from which fuel areal density (rhoR), ion temperature (T(i)), and yield (Y(n)) can be determined. The results from the first MRS measurements of the absolute neutron spectrum are presented. In addition, measuring rhoR at the National Ignition Facility (NIF) [G. H. Miller et al., Nucl. Fusion 44, S228 (2004)] will be essential for assessing implosion performance during all stages of development from surrogate implosions to cryogenic fizzles to ignited implosions. To accomplish this, we are also developing an MRS for the NIF. As much of the research and development and instrument optimization of the MRS at OMEGA are directly applicable to the MRS at the NIF, a description of the design and characterization of the MRS on the NIF is discussed as well.

A full range DT reaction history of an ignition capsule, from 10(9) to 10(20) neutronsns, offers the opportunity to diagnose fuel conditions hundreds of picoseconds before and during burn. The burn history begins with a sharp rise when the first shock reaches the center of the capsule. The level of this jump reflects the combined shock strength and the adiabat of DT fuel. Changes to the four laser pulses driving the capsule implosion which are large enough to degrade the yield make measurable changes to the reaction history. Low mode asymmetries grow during convergence but change the reaction history during the final approximately 100 ps. High mode asymmetry or turbulence mixing affects only the reaction history within approximately 50 ps of peak burn rate. A capsule with a tritium fuel layer containing a small amount of deuterium (approximately 1%) creates a reaction history similar to the ignition capsule, but without the final ignition burn. A combination of gas Cerenkov detectors and the neutron temporal diagnostic could be capable of diagnosing the full history of ignition and tritium rich capsules.

The Chesapeake Bay Interpretive Buoy System (CBIBS) is an innovative system to collect, transmit and interpret real-time environmental data from the Chesapeake Bay to a wide variety of constituents - including scientists, on-the-water users, educators, and natural resource decision-makers - and to fill critical observational gaps in the Chesapeake Bay. CBIBS is a component of the Chesapeake Bay Observing System (CBOS) and the US Integrated Ocean Observing System (IOOS), addressing IOOS goals in the Chesapeake Bay region. The CBIBS platforms provide critical real-time data on environmental conditions and water quality, and the supporting data management and delivery systems system deliver products and interpretive information of interest to the targeted user segments utilizing multiple media methods. Primary interfaces are though the web site WWW.BUOYBAY.ORG and via an extensive data and information voice application at 877-BUOYBAY. The System delivers high quality educational content based on real-time and archived data and expands the delivery of meaningful watershed educational experiences to promote environmental stewardship of Chesapeake Bay. The System is also an integral interpretive component of the National Park Service's Captain John Smith Chesapeake National Historic Trail. CBIBS buoys are presently deployed at six locations on the Chesapeake Bay: Near the mouths of the Potomac, Patapsco, Rappahannock, and Susquehanna Rivers; and in the James and Elizabeth Rivers. CBIBS platforms are AXYS Watchkeeper buoys with standard sensors including meteorological (wind speed and direction, air temperature, relative humidity, barometric pressure); water quality (WETLabs WQM measuring temperature, conductivity, pressure, dissolved oxygen, turbidity, and chlorophyll A); current profiles (Nortek Aquadopp Profilers); and waves (TRIAXYS wave sensors). Some platforms are also measuring nitrates (Satlantic ISUS) and GPS-derived water level. Real time data are reported at 10 minute to 1 hour intervals, depending on the parameter, via EVDO wireless Broadband static IP modems. The interpretive nature of the buoys, their use of multiple media (phone, web, mobile devices) to deliver data, and the educational curricula that are being built around them, are unique to this system. Support for operational oceanographic measurements from a broad and diverse user base is a critical asset to maintaining long term sustainability and funding for a system.

The Chesapeake Bay Interpretive Buoy System (CBIBS) collects real-time measurements of currents and directional waves from a series of small buoys designed for coastal regions. The buoys use an AXYS Technologies TRIAXYS directional wave sensor and a downward looking 1 MHz Nortek Aquadopp Profiler for current profiles. In this experiment, a bottom mounted Nortek acoustic wave and current (AWAC) profiler was deployed next to one buoy in 7 m water for 1 month (April 2008) to collect reference current and wave data to evaluate the performance of the buoy wave gauge in the small, short waves common to the region, and to understand how buoy motion affects the fidelity of the current measurements. Over 75% of the total current velocity energy was well described by a regional tidal model. The buoy-mounted current profiler compared well with the bottom-mounted current profiler in both speed and direction at all depth cells. For all currents greater than 0.1 m/s, the mean of the absolute value of the difference in current magnitude was less than 0.01 m/s. The mean of the absolute value of difference in current direction was 5deg. An analysis of average intervals demonstrated that an average interval of 2 minutes achieved 96% of the best possible measurement compared to a 10 minute average. Significant wave height ranged from 0.1-0.7 m and peak periods varied from 2-4 s. The buoy mounted wave gauge reported wave period accurately, but may under-report significant wave height. Wave direction between the buoy and AWAC agreed well for all waves greater than about 0.25 m.

This article examines the distributive effect of expanding the Minnesota sales tax Abstract base to include additional consumption items. Two indexes, Kakwani and the Suits, are calculated for the existing sales tax base and expansion options. The indexes consistently indicate that the existing tax base is regressive, as are the major base expansion items. Effective tax rates indicate that expanding the sales tax will widen the burden gap between low-income and high-income taxpayers. The aggregate property of the Kakwani and Suits indexes is used to examine the overall distributive effect of sales tax and other tax systems.

Recent Hurricanes Katrina and Isabel, among others, not only demonstrated their immense destructive power, but also revealed the obvious, crucial need for improved storm surge forecasting and information delivery to save lives and property in future storms. Current operational methods and the storm surge and inundation products do not adequately meet requirements needed by Emergency Managers (EMs) at local, state, and federal levels to protect and inform our citizens. The Chesapeake Bay Inundation Prediction System (CIPS) is being developed to improve the accuracy, reliability, and capability of flooding forecasts for tropical cyclones and non-tropical wind systems such as nor'easters by modeling and visualizing expected on-land storm-surge inundation along the Chesapeake Bay and its tributaries. An initial prototype has been developed by a team of government, academic and industry partners through the Chesapeake Bay Observing System (CBOS) of the Mid-Atlantic Coastal Ocean Observing Regional Association (MACOORA) within the Integrated Ocean Observing System (IOOS). For demonstration purposes, this initial prototype was developed for the tidal Potomac River in the Washington, DC metropolitan area. The preliminary information from this prototype shows great potential as a mechanism by which NOAA National Weather Service (NWS) Forecast Offices (WFOs) can provide more specific and timely forecasts of likely inundation in individual localities from significant storm surge events. This prototype system has shown the potential to indicate flooding at the street level, at time intervals of an hour or less, and with vertical resolution of one foot or less. This information will significantly improve the ability of EMs and first responders to mitigate life and property loss and improve evacuation capabilities in individual communities. This paper provides an update and expansion of the initial prototype that was presented at the Oceans 2006 MTS/IEEE Conference in Boston, MA.

The advent of imatinib therapy in gastrointestinal stromal tumor (GIST) has been transformative, altering the treatment of advanced disease in the majority of patients from supportive care and poor prognosis to a median 24-month progression free survival in the first line setting. However, for 20% of patients with gastric GIST, imatinib shows no therapeutic benefit. These patients are characterized by the amino acid substitution D842V in the PDGFRα protein; this mutation results in ligand-independent activation of PDGFRα and is insensitive to all small molecule inhibitors approved for GIST. When metastatic, the prognosis for PDGFRα D842V GIST is dire, with median overall survival of 12 months. Starting with a novel chemical library optimized for kinase selectivity and potency, we have identified BLU-285, a small molecule kinase inhibitor that potently inhibits PDGFRα D842V mutant activity in vitro (IC50 = 0.5 nM) and PDGFRα D842V autophosphorylation in the cellular setting (IC50 = 30 nM). We have observed that in addition to PDGFRα D842V, BLU-285 is also a potent inhibitor of the analogous KIT mutation, D816V in KIT Exon 17 (IC50 = 0.5nM). KIT D816 mutations have been identified in several human diseases such as systemic mastocytosis (SM), acute myeloid leukemia (AML), and as resistance mutations in second and third line GIST, after imatinib and sunitinib failure. Cellular assays measuring inhibition of KIT mutant autophosphorylation confirm the activity of BLU-285 against the KIT D816 mutants D816V (HMC1.2 cells, IC50 = 3 nM) and D816Y (P815 cells, IC50 = 22 nM) as well as other KIT Exon 17 mutants such as N822K (Kasumi cells, IC50 = 40 nM) found in treatment-refractory GIST. In vivo, BLU-285 is a well-tolerated, orally bioavailable agent that achieves dose dependent tumor growth inhibition in a D816Y-driven xenograft model. A PK-PD-efficacy relationship with BLU-285 has been established demonstrating that tumor regression results from >90% target suppression and is observed with 30 mg/kg once daily dosing. Furthermore, in non-clinical toxicology studies, projected human efficacious exposures were well tolerated. With potent activity against PDGFRα D842V and KIT Exon 17 mutants, BLU-285 targets previously unaddressed genomic drivers of disease and provides promise for the treatment of PDGFRα D842V-driven GIST or SM, where more than 90% of patients carry the KIT D816V mutation. Besides single agent activity, the highly selective BLU-285 offers an opportunity for combination with other agents in GIST to cover the entirety of KIT primary and resistance mutants. This approach of pairing potent, selective kinase inhibitors with defined disease-driving kinase mutants is designed to fulfill the promise of personalized medicine and, if clinically proven, may provide maximum benefit to patients. BLU-285 is scheduled to enter first-in-human phase 1 clinical trials for both the GIST and SM patient populations in the first half of 2015. Citation Format: Erica K. Evans, Brian L. Hodous, Alexandra K. Gardino, Alison Davis, Julia Zhu, Adam Shutes, Joseph L. Kim, Kevin J. Wilson, Doug Wilson, Yulian Zhang, Tat Chu, Nancy E. Kohl, Vivek Kadambi, Timothy Guzi, Christoph Lengauer. BLU-285, the first selective inhibitor of PDGFRα D842V and KIT Exon 17 mutants. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 791. doi:10.1158/1538-7445.AM2015-791