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In many inertial confinement fusion (ICF) experiments, the neutron yield and other parameters cannot be completely accounted for with one and two dimensional models. This discrepancy suggests that there are three dimensional effects that may be significant. Sources of these effects include defects in the shells and defects in shell interfaces, the fill tube of the capsule, and the joint feature in double shell targets. Due to their ability to penetrate materials, x rays are used to capture the internal structure of objects. Methods such as computational tomography use x-ray radiographs from hundreds of projections, in order to reconstruct a three dimensional model of the object. In experimental environments, such as the National Ignition Facility and Omega-60, the availability of these views is scarce, and in many cases only consists of a single line of sight. Mathematical reconstruction of a 3D object from sparse views is an ill-posed inverse problem. These types of problems are typically solved by utilizing prior information. Neural networks have been used for the task of 3D reconstruction as they are capable of encoding and leveraging this prior information. We utilize half a dozen, different convolutional neural networks to produce different 3D representations of ICF implosions from the experimental data. Deep supervision is utilized to train a neural network to produce high-resolution reconstructions. These representations are used to track 3D features of the capsules, such as the ablator, inner shell, and the joint between shell hemispheres. Machine learning, supplemented by different priors, is a promising method for 3D reconstructions in ICF and x-ray radiography, in general.

Thomson scattering of laser light is one of the most fundamental diagnostics of plasma density, temperature and magnetic fields. It relies on the assumption that the properties in the probed volume are homogeneous and constant during the probing time. On the other hand, laboratory plasmas are seldom uniform and homogeneous on the temporal and spatial dimensions over which data is collected. This is partic- ularly true for laser-produced high-energy-density matter, which often exhibits steep gradients in temperature, density and pressure, on a scale determined by the laser focus. Here, we discuss the modification of the cross section for Thomson scattering in fully-ionized media exhibiting steep spatial inhomogeneities and/or fast temporal fluctuations. We show that the predicted Thomson scattering spectra are greatly altered compared to the uniform case, and may even lead to violations of detailed balance. Therefore, careful interpretation of the spectra is necessary for spatially or temporally inhomogeneous systems., 18 pages, 4 figures. Publication with corrected referencing for submitted article: http://www.nature.com/articles/srep24283

For arbitrary level filling, the fully non-local kinetic energy density and Pauli potential for the one-dimensional harmonic oscillator can be constructed explicitly. These exact results are eventually compared with the low-order gradient expansions. This prompts a fuller study of the dimensionality dependence of low-order gradient expansions for systems with general one-body potentials, and its relevance to the theory of the Pauli potential. One consequence of the present work is to display the generalization to D-dimensions as (D-2)/3D of the three-dimensional Kirzhnits coefficient (1957) 1/9 of the von Weizsacker term in the kinetic energy density.

It is shown by combining the Euler equation of density functional theory with the differential form of the virial theorem that the single-particle kinetic-energy density Ts[ρ], on the minimum, and for N fermions, is a function solely of ρ, ρ' and x. This formal result is illustrated by taking the example of a harmonic oscillator with N levels filled. Model forms of Ts[ρ] and δTs[ρ]/δρ then follow.

A method of forming polycrystalline silicon (polysilicon) from amorphous silicon in several seconds is presented in this letter. This solid‐phase crystallization process was carried out with the pulsed rapid thermal annealing method using a metal as the seed. The crystal‐growth process was monitored with an optical microscope and the polysilicon structure was confirmed by a micro‐Raman shift measurement. Polysilicon film within a 30‐micrometer channel was formed using 3 pulses of 1‐s 800 °C heating/5‐s cooling. It took more than 13 h using a 500 °C furnace annealing method to form polysilicon film within a 12‐micrometer channel. Since the substrate is only exposed to the high temperature for a very short period of time, heat effects in the substrate are minimized. This method has the potential for use in the fabrication of small geometry devices, such as thin film transistors, on large‐area, low temperature glass substrates.

The application of laparoscopic procedures to the field of urology continues to expand at a rapid rate. The initial animal studies performed in the late 1980s were brought into the clinical arena by 1990. The first widely accepted procedure was laparoscopic pelvic lymph node dissection for the staging of prostate cancer. Since that time, numerous laparoscopic procedures have been developed and accepted. Herein we discuss laparoscopic pelvic lymph node dissection for the staging evaluation of cancer of the prostate with possible applications to the bladder, urethra, and penis. The technique of laparoscopic retroperitoneal lymph node dissection has been used for cancer of the testes and will also be described. The indications and a brief review of the postoperative results will also be discussed for each malignancy.

Earlier work on the Pauli potential V Pauli , which allows the square root of the electron density to be calculated directly from a Schrodinger equation, is generalized from two-level (radial) systems such as the Be atom to the n-level case in one dimension. This is achieved using hyperspherical functions, in terms of which the first- and second-order density matrices are expressed. It is confirmed that V Pauli can be constructed from the ground-state density ρ(x) and its first two derivatives, plus the functional derivative of the single-particle kinetic energy with respect to ρ. Finally, contact is made with the Harriman construction, but now using approximate one-body orbitals

Time-dependent density functional theory (TDDFT) has been applied to the analysis of the electronic spectra of methylcobalamin (MeCbl) and its derivative in which the trans axial base was replaced by a water molecule (MeCbi[Single Bond]H(2)O). The latter corresponds to the situation encountered in strongly acidic solutions. The study primarily focuses on the accuracy of two functionals, the hybrid B3LYP and the gradient corrected BP86, in dealing with the electronic excitations. The high resolution crystal structure of MeCbl was the source of the initial coordinates. To generate the initial structures, the full MeCbl was simplified by replacing the corrin side chains by H atoms. The vertical excitation energies, together with the corresponding oscillator strengths, were calculated at the optimized BP86 and B3LYP structures of the ground electronic state of the complexes. The NBO analysis shows that the B3LYP functional gives a bonding description of the ground state as a more polarized covalent bond compared to that given by BP86. The latter functional has more covalent bonding and is thus more appropriate for modeling the axial bonding properties. To validate the accuracy of the present TDDFT analysis, the computed excitations were directly compared to the absorption spectra of MeCbl. In order to obtain a reliable agreement between experiment and theory, the two-parameter scaling technique was introduced, which compensates differently the low-energy and high-energy excitations. Electronic excitations strongly depend on the choice of the functional. Transitions involving corrin pi-->pi(*) excitations are better described by the B3LYP functional while transitions associated with metal-to-ligand (dpi-->pi(*)d) excitations are better described by BP86. These differences can be associated with the different bonding descriptions obtained by B3LYP and BP86.