We describe the design and operation of a high-throughput facility for synthesizing thousands of inorganic crystalline samples per year and evaluating them as potential scintillation detector materials. This facility includes a robotic dispenser, arrays of automated furnaces, a dual-beam X-ray generator for diffractometery and luminescence spectroscopy, a pulsed X-ray generator for time response measurements, computer-controlled sample changers, an optical spectrometer, and a network-accessible database management system that captures all synthesis and measurement data.

Ovarian epithelial carcinomas (OEC) frequently exhibit amplifications at the 20q13 locus which is the site of several oncogenes, including the eukaryotic elongation factor EEF1A2 and the transcription factor ZNF217. We reported previously that overexpressed ZNF217 induces neoplastic characteristics in precursor cells of OEC. Unexpectedly, ZNF217, which is a transcriptional repressor, enhanced expression of eEF1A2. In this study, array comparative genomic hybridization, single nucleotide polymorphism and Affymetrix analysis of ZNF217-overexpressing cell lines confirmed consistently increased expression of eEF1A2 but not of other oncogenes, and revealed early changes in EEF1A2 gene copy numbers and increased expression at crisis during immortalization. We defined the influence of eEF1A2 overexpression on immortalized ovarian surface epithelial cells, and investigated interrelationships between effects of ZNF217 and eEF1A2 on cellular phenotypes. Lentivirally induced eEF1A2 overexpression caused delayed crisis, apoptosis resistance and increases in serum-independence, saturation densities, and anchorage independence. siRNA to eEF1A2 reversed apoptosis resistance and reduced anchorage independence in eEF1A2-overexpressing lines. Remarkably, siRNA to eEF1A2 was equally efficient in inhibiting both anchorage independence and resistance to apoptosis conferred by ZNF217 overexpression. Our data define neoplastic properties that are caused by eEF1A2 in nontumorigenic ovarian cancer precursor cells, and suggest that eEF1A2 plays a role in mediating ZNF217-induced …

This paper describes the development of an electron gun for a sheet beam klystron. Initially intended for accelerator applications, the gun can operate at a higher perveance than one with a cylindrically symmetric beam. Results of 2D and 3D simulations are discussed.

The carbon-to-oxygen ratios and graphitic nature of a rangeof black carbon standard reference materials (BC SRMs), high molecularmass humic-like substances (HULIS) and atmospheric particles are examinedusing scanning transmission X-ray microscopy (STXM) coupled with nearedge X-ray absorption fine structure (NEXAFS) spectroscopy. UsingSTXM/NEXAFS, individual particles with diameter>100 nm are studied,thus the diversity of atmospheric particles collected during a variety offield missions is assessed. Applying a semi-quantitative peak fittingmethod to the NEXAFS spectra enables a comparison of BC SRMs and HULIS toparticles originating from anthropogenic combustion and biomass burns,thus allowing determination of the suitability of these materials forrepresenting atmospheric particles. Anthropogenic combustion and biomassburn particles can be distinguished from one another using both chemicalbonding and structural ordering information. While anthropogeniccombustion particles are characterized by a high proportion ofaromatic-C, the presence of benzoquinone and are highly structurallyordered, biomass burn particles exhibit lower structural ordering, asmaller proportion of aromatic-C and contain a much higher proportion ofoxygenated functional groups.

Consequence analysis to support documented safety analysis requires the use of one or more years of representative meteorological data for atmospheric transport and dispersion calculations. At minimum, the needed meteorological data for most atmospheric transport and dispersion models consist of hourly samples of wind speed and atmospheric stability class. Atmospheric stability is inferred from measured and/or observed meteorological data. Several methods exist to convert measured and observed meteorological data into atmospheric stability class data. In this paper, one year of meteorological data from a western Department of Energy (DOE) site is processed to determine atmospheric stability class using two methods. The method that is prescribed by the U.S. Nuclear Regulatory Commission (NRC) for supporting licensing of nuclear power plants makes use of measurements of vertical temperature difference to determine atmospheric stability. Another method that is preferred by the U.S. Environmental Protection Agency (EPA) relies upon measurements of incoming solar radiation, vertical temperature gradient, and wind speed. Consequences are calculated and compared using the two sets of processed meteorological data from these two methods as input data into the MELCOR Accident Consequence Code System 2 (MACCS2) code.

The Galactic diffuse emission is potentially able to reveal much about the sources and propagation of cosmic rays (CR), their spectra and intensities in distant locations. It can possibly unveil WIMP dark matter (DM) through its annihilation signatures. The extragalactic background may provide vital information about the early stages of the universe, neutralino annihilation, and unresolved sources (blazars) and their cosmological evolution. The g-ray instrument EGRET on the CGRO contributed much to the exploration of the Galactic diffuse emission. The new NASA Gamma-ray Large Area Space Telescope (GLAST) is scheduled for launch in 2007; study of the diffuse g-ray emission is one of the priority goals. We describe current understanding of the diffuse emission and its potential for future discoveries.

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Vascular stents are small tubular scaffolds used in the treatment of arterial stenosis (narrowing of the vessel). Most vascular stents are metallic and are deployed either by balloon expansion or by self-expansion. A shape memory polymer (SMP) stent may enhance flexibility, compliance, and drug elution compared to its current metallic counterparts. The purpose of this study was to describe the fabrication of a laser-activated SMP stent and demonstrate photothermal expansion of the stent in an in vitro artery model. A novel SMP stent was fabricated from thermoplastic polyurethane. A solid SMP tube formed by dip coating a stainless steel pin was laser-etched to create the mesh pattern of the finished stent. The stent was crimped over a fiber-optic cylindrical light diffuser coupled to an infrared diode laser. Photothermal actuation of the stent was performed in a water-filled mock artery. At a physiological flow rate, the stent did not fully expand at the maximum laser power (8.6 W) due to convective cooling. However, under zero flow, simulating the technique of endovascular flow occlusion, complete laser actuation was achieved in the mock artery at a laser power of {approx}8 W. We have shown the design and fabrication of an SMP stent and …

We studied the problematic of uncertainties in the diffuse gamma radiation apparent in stacking analysis of EGRET data at low Galactic latitudes. Subsequently, we co-added maps of counts, exposure and diffuse background, and residuals, in varying numbers for different sub-categories of putatively and known source populations (like PSRs). Finally we tested for gamma-ray excess emission in those maps and attempt to quantify the systematic biases in such approach. Such kind of an analysis will help the classification processes of sources and source populations in the GLAST era.

We describe here the data acquisition subsystem of the Quick EXAFS (QEXAFS) experiment at the National Synchrotron Light Source of Brookhaven National Laboratory. For ease of future growth and flexibility, almost all software components are open source with very active maintainers. Among them, Linux running on x86 desktop computer, RTAI for real-time response, COMEDI driver for the data acquisition hardware, Qt and PyQt for graphical user interface, PyQwt for plotting, and Python for scripting. The signal (A/D) and energy-reading (IK220 encoder) devices in the PCI computer are also EPICS enabled. The control system scans the monochromator energy through a networked EPICS motor. With the real-time kernel, the system is capable of deterministic data-sampling period of tens of micro-seconds with typical timing-jitter of several micro-seconds. At the same time, Linux is running in other non-real-time processes handling the user-interface. A modern Qt-based controls-front end enhances productivity. The fast plotting and zooming of data in time or energy coordinates let the experimenters verify the quality of the data before detailed analysis. Python scripting is built-in for automation. The typical data-rate for continuous runs are around ten mega-bytes per minute.

The authors present updated measurements of time-dependent CP asymmetries in fully-reconstructed neutral B decays to several CP eigenstates containing a charmonium meson. The measurements use a data sample of (383 {+-} 4) x 10{sup 6} {Upsilon}(4S) {yields} B{bar B} decays collected with the BABAR detector at the PEP-II B factory. They determine sin2{beta} = 0.714 {+-} 0.032(stat) {+-} 0.018(syst) and |{lambda}| = 0.952 {+-} 0.022(stat) {+-} 0.017(syst).

The electronic structure of nanowires in contact withmetallic electrodes of experimentally relevant sizes is calculated byincorporating the electrostatic polarization potential into the atomisticsingle particle Schrodinger equation. We show that the presence of anelectrode produces localized electron/hole states near the electrode, aphenomenon only exhibited in nanostructures and overlooked in the past.This phenomenon will have profound implications on electron transport insuch nanosystems. We calculate several electrode/nanowire geometries,with varying contact depths and nanowire radii. We demonstrate the changein the band gap of up to 0.5 eV in 3 nm diameter CdSe nanowires andcalculate the magnitude of the applied electric field necessary toovercome the localization.

The authors perform the first three-dimensional measurement of the amplitudes of B {yields} {psi}(2S)K* and B {yields} {chi}{sub c1}K* decays and update the previous measurement B {yields} J/{psi}K*. They use a data sample collected with the BABAR detector at the PEP-II storage ring, corresponding to 232 million B{bar B} pairs. The longitudinal polarization of decays involving a J{sup PC} = 1{sup ++} {chi}{sub c1} meson is found to be larger than that with a 1{sup --} J/{psi} or {psi}(2S) meson. No direct CP-violating charge asymmetry is observed.

The authors measure the absolute branching fraction for D{sup 0} {yields} K{sup -} {pi}{sup +} using partial reconstruction of {bar B}{sup 0} {yields} D*{sup +}X{ell}{sup -}{bar {nu}}{sub {ell}} decays, in which only the charged lepton and the pion from the decay D*{sup +} {yields} D{sup 0}{pi}{sup +} are used. Based on a data sample of 230 million B{bar B} pairs collected at the {Upsilon}(4S) resonance with the BABAR detector at the PEP-II asymmetric-energy B Factory at SLAC, they obtain {Beta}(D{sup 0} {yields} K{sup -}{pi}{sup +}) = (4.007 {+-} 0.037 {+-} 0.070)%, where the first error is statistical and the second error is systematic.

Population III Stars (PopIII) are the first generation of stars formed from the collapse of the very first structures in the Universe. Their peculiar chemical composition (metal-free, resembling the Primordial Nucleosynthesis yields) affects their formation and evolution and makes them unusually big and hot stars. They are good candidates for the engines of Reionization of the Universe although their direct observation is extremely difficult. Here we summarize a study of their expected diffuse low-energy neutrino background flux at Earth.

The design of final focus systems for the next generation of linear colliders has evolved largely from the experience gained with the design and operation of the Stanford Linear Collider (SLC) and with the design of the Final Focus Test Beam (FFTB). We will compare the tolerances for two typical designs for a next-generation linear collider final focus system. The chromaticity generated by strong focusing systems, like the final quadrupole doublet before the interaction point of a linear collider, can be canceled by the introduction of sextupoles in a dispersive region. These sextupoles must be inserted in pairs separated by a -I transformation (Chromatic Correction Section) in order to cancel the strong geometric aberrations generated by sextupoles. Designs proposed for both the JLC or NLC final focus systems have two separate chromatic correction sections, one for each transverse plane separated by a ''{beta}-exchanger'' to manipulate the {beta}-function between the two CCS. The introduction of sextupoles and bending magnets gives rise to higher order aberrations (long sextupole and chrome-geometries) and radiation induced aberrations (chromaticity unbalance and ''Oide effect'') and one must optimize the lattice accordingly.

We review on-shell methods for computing multi-parton scattering amplitudes in perturbative QCD, utilizing their unitarity and factorization properties. We focus on aspects which are useful for the construction of one-loop amplitudes needed for phenomenological studies at the Large Hadron Collider.

In the next-generation linear colliders, the low-energy e{sup +}e{sup -} pairs created during the collision of high-energy e{sup +}e{sup -} beams would cause potential deleterious background problems to the detectors. At low collider energies, the pairs are made essentially by the incoherent process, where the pair is created by the interaction of beamstrahlung photons on the individual particles in the oncoming beam. This problem was first identified by Zolotarev, et al[1]. At energies where the beamstrahlung parameter {Upsilon} lies approximately in the range 0.6 {approx}< {Upsilon} {approx}< 100, pair creation from the beamstrahlung photons is dominated by a coherent process, first noted by Chen[2]. The seriousness of this pair creation problem lies in the transverse momenta that the pair particles carry when leaving the interaction point (IP) with large angles. One source of transverse momentum is from the kick by the field of the oncoming beam which results in an outcoming angle {theta} {proportional_to} 1/{radical}x, where x is the fractional energy of the particle relative to the initial beam particle energy[2,3]. As was shown in Ref. 131, there in fact exists an energy threshold for the coherent pairs, where x{sub th} {approx}> 1/2{Upsilon}. Thus within a tolerable exiting angle, there …

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Solidification of polymeric materials, a complex process in which the entangled polymer melt becomes a composite of amorphous and crystalline domains, strongly depends on how the melt is cooled below its crystallization temperature. If cooling is at moderate rates, the most common and well. understood mechanism is via nucleation and growth of spherulites, but special cases exist where crystallization is preceded by a pre pre-transition state induced by density fluctuations. Such multi-step crystallization scenarios are suggested by many experiments, and recent theoretical and simulation work. Via energetic and geometric analyses, we have examined the structure of mesomorphic domains and the dynamics of their formation and evolution, including atomic scale details of molecular addition to ordered domains, as well as particle dynamics in the system, including high mobility jumps in the ordered domains at wavelengths matching the monomer spacing.

We report recent progress of x-ray diagnostic techniques in laser plasma experiment with using imaging plates. Imaging plate is a photo-stimulable phosphor screen (BaF(Br0.85,10.15):Eu{sup 2+}) deposited on flexible metal or plastic substrate. We applied the imaging plate to x-ray microscopy in laser fusion experiment experiments. Self-emission x-ray images of imploded core were obtained successfully with using imaging plate and high magnification target mounted pinhole arrays. The imaging plates were applied also in ultra-intense laser experiment at the Rutherford Appleton Laboratory. Small samarium foil was irradiated by high intensity laser pulse from the Vulcan laser system. The k shell x-rays from the foil ({approx}40keV) was used as a line x-ray source for microscopic radiography. Performance of imaging plate on high-energy x-ray backlit radiography was demonstrated by imaging sinusoidal grooves of 6um amplitude on a Au foil. Detailed spectrum of k shell x-ray from Cu embedded foil target was successfully observed by fully coupling imaging plate with a highly ordered pyrolytic graphite crystal spectrometer. The performances of the imaging plates evaluated in actual laser plasma experiments will be presented.

We report on the first single-state measurement of the broadband (450-800 nm) dielectric function of gold isochorically heated by a femtosecond laser pulse to energy densities of 10{sup 6}-10{sup 7} J/kg. A Drude and an inter-band component are clearly seen in the imaginary part of the dielectric function. The Drude component increases with energy density while the inter-band component shows both enhancement and red shift. This is in strong disagreement with predictions of a recent calculation of dielectric function based on limited k-point sampling.

The thermoelastic properties of bcc tantalum have been investigated over a broad range of pressures (up to 10 Mbar) and temperatures (up to 26,000 K) using a new first-principles approach that accurately accounts for cold, electron-thermal, and ion-thermal contributions in materials where anharmonic effects are small. Specifically, we have combined ab initio full-potential linear-muffin-tin-orbital (FP-LMTO) electronic-structure calculations for the cold and electron-thermal contributions to the elastic moduli with phonon contributions for the ion-thermal part calculated using model generalized pseudopotential theory (MGPT). For the latter, a summation of terms over the Brillouin zone is performed within the quasi-harmonic approximation, where each term is composed of a strain derivative of the phonon frequency at a particular k point. At ambient pressure, the resulting temperature dependence of the Ta elastic moduli is in excellent agreement with ultrasonic measurements. The experimentally observed anomalous behavior of C{sub 44} at low temperatures is shown to originate from the electron-thermal contribution. At higher temperatures, the main contribution to the temperature dependence of the elastic moduli comes from thermal expansion, but inclusion of the electron- and ion-thermal contributions is essential to obtain quantitative agreement with experiment. In addition, the pressure dependence of the moduli at ambient temperature compares …

Hard x-ray (''Thin wall'') imaging will be employed on the National Ignition Facility (NIF) to spatially locate laser beam energy deposition regions on the hohlraum walls in indirect drive Inertial Confinement Fusion (ICF) experiments, relevant for ICF symmetry tuning. Based on time resolved imaging of the hard x-ray emission of the laser spots, this method will be used to infer hohlraum wall motion due to x-ray and laser ablation and any beam refraction caused by plasma density gradients. In optimizing this measurement, issues that have to be addressed are hard x-ray visibility during the entire ignition laser pulse with intensities ranging from 10{sup 13} to 10{sup 15} W/cm{sup 2}, as well as simultaneous visibility of the inner and the outer laser drive cones. In this work we will compare the hard x-ray emission calculated by LASNEX and analytical modeling with thin wall imaging data recorded previously on Omega and during the first hohlraum experiments on NIF. Based on these calculations and comparisons the thin wall imaging will be optimized for ICF/NIF experiments.