This article is a study investigating fake news included in political discourse of opposing activism hashtags, #Gunreformnow and #NRA (The National Rifle Association) and aims to lay out the process of identifying fake news in the hashtag activism network on Twitter.

This article develops and validates a sequential protocol for quantifying reserve and structural carbohydrates in soybean seed. It was successfully applied to eight soybean genotypes harvested from two locations, and the resulting correlations of carbohydrate and oil or protein are presented. This methodology has the potential not only to guide soybean cultivar optimization processes but also to be expanded to other crops with only slight modifications.

Article describes study which develops a static geospatial soil moisture model, the Soil Moisture Proxy Model, which uses soil and topographic variables to estimate soil moisture potential across a watershed in order to better understand the quality of farmland in terms of soil moisture.

Study examines factors that affect power corridor classification using LiDAR (light detection and ranging) point clouds, including the class distribution, feature selection, classifier type and neighborhood radius for classification feature extraction.

Use of the National Ignition Facility to also output frequency-doubled (.53{micro}m) laser light would allow significantly more energy to be delivered to targets as well as significantly greater bandwidth for beam smoothing. This green light option could provide access to new ICF target designs and a wider range of plasma conditions for other applications. The wavelength scaling of the interaction physics is a key issue in assessing this green light option. Wavelength scaling theory based on the collisionless plasma approximation is explored, and some limitations associated with plasma collisionality are examined. Important features of the wavelength scaling are tested using the current data base, which is growing. It appears that, with modest restrictions, .53{micro}m light couples with targets as well as .35{micro}m light does. A more quantitative understanding of the beneficial effects of SSD on the interaction physics is needed for both .53{micro}m and .35{micro}m light.

The authors investigate hydrodynamic instability of accelerating ionization fronts with two dimensional hydrodynamic simulations. When recombination in the ionized region is turned off, Rayleigh-Taylor instability is effective. Perturbation grows up with classical Rayleigh-Taylor growth rate. In the case with recombination, the local difference of absorption profile works to smooth the surface. The perturbation does not grow and the amplitude follows a damped oscillations with time.

Sapphire, a common optical window material used in shock-compression studies, displays significant shock-induced optical emission and extinction. It is desirable to quantify such non-ideal window behavior to enhance the usefulness of sapphire in optical studies of opaque shock-compressed samples, such as metals. At the highest stresses we can achieve with a two-stage gas gun it is technically very difficult to study the optical properties of sapphire without the aid of some opaque backing material, hence one is invariably compelled to deconvolve the optical effects of the opaque surface and the sapphire. In an effort to optimize this deconvolution process, we have constructed sapphire/thin-film/sapphire samples using two basic types of thin films: one optimized to emit copious optical radiation (the hot-film sample), the other designed to yield minimal emission (the cold-film sample). This sample geometry makes it easy to maintain the same steady shock-stress in the sapphire window (255 GPa in our case) while varying the window/film interface temperature. A six-channel time-resolved optical pyrometer is used to measure the emission from the sample assemblies. Two different sapphire crystal orientations were evaluated. We also comment on finite thermal conductivity effects of the thin-film geometry on the interpretation of our data.

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For a particle beam propagating in an alternating gradient focusing system, envelope equations are often employed to describe the evolution of the beam radii in the two directions transverse to the direction of propagation, and aligned with the principle axes of the alternating gradient system. When the beams have zero net angular momentum and when the alternating gradient focusing is approximated by a continuous focusing system, there are two normal modes to the envelope equations: the 'breathing' mode and a 'quadrupole' mode. In the former, the two radii oscillate in phase, and in the latter the radii oscillate 180 degrees out of phase. In this paper, we extend the analysis to include beams that have a finite angular momentum. We perturb the moment equations of ref. [1], wherein it was assumed that space charge is a distributed in a uniform density ellipse. Two additional modes are obtained. The breathing mode remains, but the quadrupole mode is split into two modes, and a new low frequency mode appears. We calculate the frequencies and eigenmodes of these four modes as a function of tune depression and a dimensionless net angular momentum. These modes can be excited by rotational errors of the quadrupoles …

Materials properties measurements are made for the RDX-based explosive, PBXN-109, and initial ALE3D model predictions are given for the cookoff temperature in a U.S. Navy test. This work is part of an effort in the U.S. Navy and Department of Energy (DOE) laboratories to understand the thermal explosion behavior of this material. Benchmark cookoff experiments are being performed by the U.S. Navy to validate DOE materials models and computer codes. The ALE3D computer code can model the coupled thermal, mechanical, and chemical behavior of heating, ignition, and explosion in cookoff tests. In our application, a standard three-step step model is selected for the chemical kinetics. The strength behavior of the solid constituents is represented by a Steinberg-Guinan model while polynomial and gamma-law expressions are used for the Equation Of State (EOS) for the solid and gas species, respectively. Materials characterization measurements are given for thermal expansion, heat capacity, shear modulus, bulk modulus, and One-Dimensional-Time-to-Explosion (ODTX). These measurements and those of the other project participants are used to determine parameters in the ALE3D chemical, mechanical, and thermal models. Time-dependent, two-dimensional results are given for the temperature and material expansion. The results show predicted cookoff temperatures slightly higher than the measured values.

We report on the construction, commissioning and characterization of a reactive ion mill capable of submicron pattern transfer into hard dielectric materials on optical substrates as large as 2 x 1 m, for application to fielding high-Energy Petawatt (HEPW) capability on the National Ignition Facility (NIF) laser. Scanning Faraday cup current probe measurements have been used to optimize the ion beam spatial uniformity. Using process parameters obtained from this study, an 81 cm round optic was etched, and etch depth uniformity of {+-} 3.1% absolute was demonstrated. Uniformity of multilayer dielectric gratings of designs employing an etch-stop layer will have etch depth uniformities of approximately a factor of 10 better than this. We also report on initial results of etching multilayer dielectric gratings.

Historically, the first demonstration of the optical FEL was in an amplifier configuration at Stanford University [l]. There were other notable instances of amplifying a seed laser, such as the LLNL PALADIN amplifier [2] and the BNL ATF High-Gain Harmonic Generation FEL [3]. However, for the most part FELs are operated as oscillators or self amplified spontaneous emission devices. Yet, in wavelength regimes where a conventional laser seed can be used, the FEL can be used as an amplifier. One promising application is for very high average power generation, for instance FEL's with average power of 100 kW or more. The high electron beam power, high brightness and high efficiency that can be achieved with photoinjectors and superconducting Energy Recovery Linacs (ERL) combine well with the high-gain FEL amplifier to produce unprecedented average power FELs. This combination has a number of advantages. In particular, we show that for a given FEL power, an FEL amplifier can introduce lower energy spread in the beam as compared to a traditional oscillator. This properly gives the ERL based FEL amplifier a great wall-plug to optical power efficiency advantage. The optics for an amplifier is simple and compact. In addition to the general features …

We investigate how well a coupled biosphere-atmosphere model, CCM3-IBIS, can simulate the functioning of the terrestrial biosphere and the carbon cycling through it. The simulated climate is compared to observations, while the vegetation cover and the carbon cycle are compared to an offline version of the biosphere model IBIS forced with observed climatic variables. The simulated climate presents some local biases that strongly affect the vegetation (e.g., a misrepresentation of the African monsoon). Compared to the offline model, the coupled model simulates well the globally averaged carbon fluxes and vegetation pools. The zonal mean carbon fluxes and the zonal mean seasonal cycle are also well represented except between 0{sup o} and 20{sup o}N due to the misrepresentation of the African monsoon. These results suggest that, despite regional biases in climate and ecosystem simulations, this coupled atmosphere-biosphere model can be used to explore geographic and temporal variations in the global carbon cycle.

We have modeled gyrotron windows and gyrotron amplifier sever structures for TE modes in the 100--150 GHz range and have computed the reflection and transmission characteristics from the field data. Good agreement with frequency domain codes and analytic analysis have been obtained for some simple geometries. We present results for realistic structures with lossy coatings and describe implementation of microwave diagnostics.

This article attempts to identify some of the components that positively affect student motivation in mobile augmented reality (AR) learning experiences to contribute to the design and development of motivational AR learning experiences for the Vocational Education and Training (VET) level of education.

Efforts devoted to searches for short-lived nuclides in the debris from large thermonuclear explosions are reviewed along with reactor production of Es and Fm. Results of underground tests are discussed along with odd-even yield variations, and future directions for heavy-element synthesis. (JRD)

The plasma closure of spatial filter pinholes is a critical parameter in the performance of high energy glass laser systems. Using 50 to 100 J, 300 psec FWHM laser pulses on the Janus laser, an investigation has been made on closure effects in 300 ..mu..m to 500 ..mu..m diameter pinholes of various materials and thicknesses. Calorimetry measurements have yielded data on pinhole transmission and intensity loading on the periphery of the pinhole. Ultrafast streak photography measurements indicate effective closure velocities of 2 x 10/sup 7/ cm/sec to 5 x 10/sup 7/ cm/sec. Scattered light measurements have shown the transmission loss through a typical spatial filter configuration to be primarily refractive in nature.

Stimulated Raman scattering in plasmas is a three-wave instability with important practical consequences for laser fusion. Most studies of this process to date have focused on its threshold. Even the linear-theory threshold poses interesting problems; and observed thresholds have been difficult to interpret. However, with increasing evidence that this instability often becomes absolute, it has become appropriate to examine saturation mechanisms as well. A number of such mechanisms are discussed here, one of which has been reported to have a chaotic regime. 26 refs., 4 figs.

HYLIFE is the name given to a family of self-healing liquid-wall reactor concepts for inertial confinement fusion. This HYLIFE-II concept employs the molten salt, Flibe, for the liquid jets instead of liquid lithium used in the original HYLIFE-I study. A preliminary conceptual design study of the heat transport system and the balance of plant of the HYLIFE-II fusion power plant is described in this paper with special emphasis on a scoping study to determine the best intermediate heat exchanger geometry and flow conditions for minimum cost of electricity. 11 refs., 8 figs.

Environmental problems consist of the release of noncondensable gases and vapors, disposal of saline fluids, possible land subsidence and enhanced seismicity, noise, accidents such as well blowouts, and socioeconomic impacts. The most important issue related to human health is believed to be the emission of noncondensable gases, including hydrogen sulfide, mercury, and radon. Based upon data at The Geysers, California, Power Plant, emissions of mercury and radon are not large enough to result in concerns for human health. Hydrogen sulfide emissions, however, have resulted in complaints of odor annoyance and health impairment. These complaints have been caused by exposure to levels of up to approximately 0.1 ppmv in ambient air. This is above the California standard of 0.03 ppmv. Achievement of this standard may not eliminate annoyance complaints, as the odor detection threshold is lognormally distributed and about 20% of the population can detect hydrogen sulfide at levels of 0.002 ppmv. Abatement systems for hydrogen sulfide have been utilized at The Geysers since 1975. This has resulted in an increase of occupational illness caused by exposure to the abatement chemicals and wastes. More effective, and hopefully safer, abatement systems are now being tested. Occupational hazards are evaluated; the more significant …

A microcomputer-based x-ray image analysis system to select and measure laser fusion targets is described. This system positions a photographic plate in x and y, focuses a microscope image, digitizes and extracts measurements within seconds.

Long-term behavior of filament-wound pressure vessels were tested, Kevlar 49 epoxy strands were studied in stress-rupture for more than a year. Because the strands are the smallest structural unit in filament winding, their behavior directly controls the performance of vessels. Five different stress levels were studied: 86, 80, 74, 68, and 50% of the mean ultimate tensile strength (UTS). At each stress level, approximately one-hundred strands were hung in a room maintained at 22 to 24/sup 0/C and below 20% relative humidity. Failure times were automatically recorded by a data acquisition system. Lifetimes were analyzed statistically using a two-parameter Weibull distribution. The maximum-likelihood method was used to estimate the parameters. The shape parameter, which is a measure of scatter and failure-rate change, increased with decreasing stress level. Less scatter and increasing failure rates were observed at lower stresses. There was no sign of an endurance limit down to 68% UTS. At 50% UTS no failure had yet occurred after 9000 h. The strand data were compared with data on lifetimes of pressure vessels wound with the same fiber and epoxy. The strands had slightly longer characteristic lifetimes, except at 86% UTS, and slightly less scatter, except at 68% UTS. The …

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In this paper we show that spinel ferrite nanocrystals (NiFe{sub 2}O{sub 4}, and CoFe{sub 2}O{sub 4}) can be texturally embedded inside a ZnO matrix by ion implantation and post-annealing. The two kinds of ferrites show different magnetic properties, e.g. coercivity and magnetization. Anomalous Hall effect and positive magnetoresistance have been observed. Our study suggests a ferrimagnet/semiconductor hybrid system for potential applications in magneto-electronics. This hybrid system can be tuned by selecting different transition metal ions (from Mn to Zn) to obtain various magnetic and electronic properties.