Dantrolene is a drug that suppresses intracellular Ca2+ release from sarcoplasmic reticulum in normal skeletal muscle and is used as a therapeutic agent in individuals susceptible to malignant hyperthermia. Though its precise mechanism of action has not been elucidated, we have identified the N-terminal region (amino acids 1-1400) of the skeletal muscle isoform of the ryanodine receptor (RyR1), the primary Ca2+ release channel in sarcoplasmic reticulum, as a molecular target for dantrolene using the photoaffinity analog [3H]azidodantrolene(1). Here, we demonstrate that heterologously expressed RyR1 retains its capacity to be specifically labeled with [3H]azidodantrolene,indicating that muscle specific factors are not required for this ligand-receptor interaction. Synthetic domain peptides of RyR1, previously shown to affect RyR1 function in vitro and in vivo, were exploited as potential drug binding site mimics and used in photoaffinity labeling experiments. Only DP1 and DP1-2, peptide s containing the amino acid sequence corresponding to RyR1 residues 590-609, were specifically labeled by [3H]azidodantrolene. A monoclonal anti-RyR1 antibody which recognizes RyR1 and its 1400 amino acid N-terminal fragment, recognizes DP1 and DP1-2 in both Western blots and immunoprecipitation assays, and specifically inhibits [3H]azidodantrolene photolabeling of RyR1 and its N-terminal fragment in sarcoplasmic reticulum. Our results indicate that synthetic domain …

The Advanced Light Source (ALS) at the E.O. Lawrence Berkeley National Laboratory (Berkeley Lab) of the University of California is a ''third-generation'' synchrotron radiation source optimized for highest brightness at ultraviolet and soft x-ray photon energies. It also provides world-class performance at hard x-ray photon energies. Berkeley Lab operates the ALS for the United States Department of Energy as a national user facility that is available 24 hours/day around the year for research by scientists from industrial, academic, and government laboratories primarily from the United States but also from abroad.

We perform an analytic semi-classical quantization of the straight QCD string with one end fixed and a massless quark on the other, in the limits of orbital and radial dominant motion. Our results well approximate those of the exact numerical semi-classical quantization as well as our exact numerical canonical quantization.

The question of the anisotropy of the electron scattering in high temperature superconductors is investigated using high resolution angle-resolved photoemission data from Pb-doped Bi2Sr2CaCu2O8(Bi2212) with suppressed superstructure. The scattering rate of low energy electrons along two bilayer split pieces of the Fermi surface is measured (via the quasiparticle peak width), and no increase of scattering towards the antinode (Pi,0) region is observed, contradicting the expectation from Q=(Pi, Pi) scattering. The results put a limit on the effects of Q=(Pi, Pi) scattering on the electronic structure of this overdoped superconductor with still very high Tc.

Long-term stewardship (LTS) can be defined as the system of activities needed to protect human health and the environment from hazards left remaining at a site as a result of a cleanup decision. Although the general consensus has been that remediation decisions and LTS decisions should be made conjointly, the general practice has been to separate them. This bifurcation can result in LTS plans that are difficult to implement and enforce and disproportionately costly for the benefit they provide. Worse still, they can be ineffective and result in harmful exposures to humans and the environment. Sites that have not yet made cleanup decisions and that can still integrate LTS planning into that decision making would benefit from a process built on a systematic review of the LTS risks and costs associated with remedial alternatives that include allowing on-site residual contamination. Sites that must develop LTS plans in response to previously determined cleanup decisions are even more in need of a process that involves close scrutiny of the risks and costs of possible LTS plan components. An LTS planning decision process usable by both categories of sites has been developed and is being used at the US Department of Energy (DOE) …

The purpose of this study is to quantify the flow and transport model uncertainty for the Central Nevada Test Area (CNTA). Six parameters were identified as uncertain, including the specified head boundary conditions used in the flow model, the spatial distribution of the underlying welded tuff unit, effective porosity, sorption coefficients, matrix diffusion coefficient, and the geochemical release function which describes nuclear glass dissolution. The parameter uncertainty was described by assigning prior statistical distributions for each of these parameters. Standard Monte Carlo techniques were used to sample from the parameter distributions to determine the full prediction uncertainty. Additional analysis is performed to determine the most cost-beneficial characterization activities. The maximum radius of the tritium and strontium-90 contaminant boundary was used as the output metric for evaluation of prediction uncertainty. The results indicate that combining all of the uncertainty in the parameters listed above propagates to a prediction uncertainty in the maximum radius of the contaminant boundary of 234 to 308 m and 234 to 302 m, for tritium and strontium-90, respectively. Although the uncertainty in the input parameters is large, the prediction uncertainty in the contaminant boundary is relatively small. The relatively small prediction uncertainty is primarily due to the …

The KEK Accelerator Test Facility (ATF) damping ring is a prototype low emittance source for the NLC/JLC linear collider. To achieve the goal normalized vertical emittance {gamma}{var_epsilon}{sub {gamma}} = 20 nm-rad, magnet placement accuracy better than 30 mm must be achieved. Accurate beam-based alignment (BBA) is required. The ATF arc optics uses a FOBO cell with two horizontally focusing quadrupoles, two sextupoles and a horizontally defocusing gradient dipole, all of which must be aligned with BBA. BBA at ATF uses the quadrupole and sextupole trim windings to find the trajectory through the center of each magnet. The results can be interpreted to assess the accuracy of the mechanical alignment and the beam position monitor offsets.

A new Detonation Profile Test (DPT) was developed to measure simultaneously the detonation wave breakout profile and the average detonation velocity at the breakout surface. The test evaluated small cylindrical samples with diameter up to 19.08 mm and length up to 33 mm. The experiment involved initiating a LX-17 cylindrical specimen and recording the wave breakout using a fast streaking electronic camera. The initiation was done using a PBX-9407 pellet (1.630 g/cm{sup 3}), which has a Chapman-Jouguet (C-J) pressure close to that of LX-17. The acceptor breakout surface had a 2 mm wide by 1 mm deep groove that provided a step in the recorded breakout profile for velocity determination. A 532-nm laser light illuminated the specimen surface. A streak camera looking perpendicular to the groove, recorded the extinction of the laser light as the detonation wave emerged from the surface. This technique provided a high-resolution spatial and temporal profile of the wave curvature as well as accurate timing of the propagating wave over the last millimeter of the sample. The measured groove depth and recorded travel time were then used to calculate the average detonation wave velocity. Results for 12.7 mm diameter unconfined LX-17 charges showed detonation velocity in …

A comparison of methods is used to evaluate the intake of transuranics influenced by chelation therapy. The purpose of this paper is to introduce the mechanistic method by using it to validate Hall's method and Jech's method. This is accomplished by using the mechanistic method to generate a known set of data suitable for benchmarking all three methods.

I present several preliminary measurements from KTeV of the fundamental neutral K parameters, and their implications for CPT violation. A new limit is given on the sidereal time dependence of {phi}{sub +-}. The results are based on data collected in 1996-97.

Prior studies of evaporation and sputter deposition show that the grain size of pure beryllium can be dramatically refined through the incorporation of metal impurities. Recently, the addition of boron at a concentration greater than 11% is shown to serve as a glassy phase former in sputter deposited beryllium. Presently, thermally induced crystallization of the beryllium-boron metallic glass is reported. The samples are characterized during an in-situ anneal treatment with bright field imaging and electron diffraction using transmission electron microscopy. A nanocrystalline structure evolves from the annealed amorphous phase and the crystallization temperature is affected by the boron concentration.

CuPt-type ordering in In{sub 0.49}Al{sub 0.51}P is studied by TEM. The lattice-matched film was grown by MOCVD on a GaAs substrate oriented 10{sup o} off (001) towards [110], at 650 C and 25 nm/min. TEM [110] and [1{bar 1}0] cross-sections (XS) were made by wedge polishing and 2 kV Ar ion milling. In CuPt-type ordering of In{sub 0.52}Ga{sub 0.48}P, alternating In-Ga-In-Ga {l_brace}111{r_brace} planes of group III atoms produce 1/2 {bar 1}11 and 1/2 1{bar 1}1 order spots in the 110 SADP, while the [1{bar 1}0] SADP shows no order spots [1-3]. A few studies have reported this type of order in In{sub 0.49}Al{sub 0.51}P [4]. The 004 BF image of the [1{bar 1}0] XS in Fig. 1 shows uneven light/dark contrast modulation due to phase separation often observed in In{sub 0.52}Ga{sub 0.48}P. There are also light/dark layers marked ML parallel to the film growth plane; such unintentional multilayers have also been observed [5] but their origin is not understood. Order lamellae {approx}1.5 nm thick inclined at a shallow angle to the growth plane overlap the multilayer to produce Moire fringe contrast. Fig. 2 is a DF image showing the thin ordered domains in the [1{bar 1}0] XS, which are inclined …

Thermal cycling was used as a means to control density in the preparation of Insensitive High Explosive (IHE) specimens slated for performance testing. These samples were thermally cycled between -55 degrees C and 70 degrees C and their densities measured using hydrostatic weighing, an immersion density measurement technique. Bulk sample densities were reduced by as much as 1.5% over 40 thermal cycles. In these thermal cycling studies, the effects of several parameters were investigated. These parameters included different ME composites (LX-17 and PBX 9502), different pressing mechanisms (die-pressed and isostatically-pressed) and sample size.

A multi-beamlet approach to a high current ion injector, whereby a large number of beamlets are accelerated and then merged to form a single beam, offers a number of potential advantages over a monolithic single beam injector. These advantages include a smaller transverse footprint, more control over the shaping and aiming of the beam, and more flexibility in the choice of ion sources. A potential drawback however is a larger emittance. In this paper, we seek to understand the merging of the beamlets and how it determines the emittance. When the constraints imposed by beam propagation physics and practical engineering issues are included, the design is reduced to a few free parameters. We describe the physics design of a multi-beamlet injector, and produce a design for an example set of parameters. Extensive use of 2-D and 3-D particle simulations was made in understanding the injector. Design tolerances and sensitivities are discussed in general and in relation to the example.

Two short Nb{sub 3}Sn dipole models based on a single-bore cos-theta coil with a cold iron yoke were fabricated and tested at Fermilab. This paper summarizes the details of magnet design and fabrication procedure, and reports the test results including quench performance and quench heater studies, and the magnetic measurements.

Authenticated Diffie-Hellman key exchange allows two principals communicating over a public network, and each holding public-private keys, to agree on a shared secret value. In this paper we study the natural extension of this cryptographic problem to a group of principals. We begin from existing formal security models and refine them to incorporate major missing details (e.g., strong-corruption and concurrent sessions). Within this model we define the execution of a protocol for authenticated dynamic group Diffie-Hellman and show that it is provably secure under the decisional Diffie-Hellman assumption. Our security result holds in the standard model and thus provides better security guarantees than previously published results in the random oracle model.

We report on the performance of an S-band RF photocathode electron gun and accelerator for operation with the PLEIADES Thomson x-ray source at LLNL. Simulations of beam production, transport, and focus are presented. It is shown that a 1 ps, 500 pC electron bunch with a normalized emittance of less than 5 {pi}mm-mrad can be delivered to the interaction point. Initial electron measurements are presented. Calculations of expected x-ray flux are also performed, demonstrating an expected peak spectral brightness of 10{sup 20} photons/s/mm{sup 2}/mrad{sup 2}/0.1% bandwidth. Effects of RF phase jitter are also presented, and planned phase measurements and control methods are discussed.

One of the primary concerns in the design and operation of high-intensity proton synchrotrons and accumulators is the electron cloud and associated beam loss and instabilities. Electron-cloud effects are observed at high-intensity proton machines like the Los Alamos National Laboratory's PSR and CERN's SPS, and investigated experimentally and theoretically. In the design of next-generation high-intensity proton accelerators like the Spallation Neutron Source ring, emphasis is made in minimizing electron production and in enhancing Landau damping. This paper reviews the present understanding of the electron-cloud effects and presents mitigation measures.

A suite of instrumentation including a minisodar, a low-frequency, single-axis sodar, a wind profiling radar and a tethersonde was used during the Vertical Transport and Mixing field study in Salt Lake City, UT, USA, to study the evolution and dynamics of stratified layers that commonly develop during nighttime. The month-long field study provided ten nights with good conditions for tethersonde flights. The real-time sodar display was used to place the tethersonde within and near the stratified layers and to make multiple transects, while atmospheric temperature, moisture, wind speed and wind direction were measured. Not surprisingly, the existence of layers with enhanced acoustic scattering correlated well with regions of potential temperature inversions; however, because wind speeds were invariably low, the Richardson number was rarely less than 0.25. The possible role of moisture in the dynamics of elevated stable layer is discussed.

Traces of tritiated water (HTO) were detected at [the]World Trade Center (WTC) ground zero after the 9/11/01 terrorist attack. A method of ultralow-background liquid scintillation counting was used after distilling HTO from the samples. A water sample from the WTC sewer, collected on 9/13/01, contained 0.174 plus or minus 0.074 (2s) nCi/L of HTO. A split water sample, collected on 9/21/01 from the basement of WTC Building 6, contained 3.53 plus or minus 0.17 and 2.83 plus or minus 0.15 nCi/L, respectively. Several water and vegetation samples were analyzed from areas outside the ground zero, located in Manhattan, Brooklyn, Queens, and Kensico Reservoir. No HTO above the background was found in those samples. All these results are well below the levels of concern to human exposure.

Recent developments in plasma synthesis of hard materials using energetic ions are described. Metal Plasma Immersion Ion Implantation and Deposition (MePIIID) has been used to prepare several hard films: from diamondlike carbon (DLC) to carbides, from nitrides to oxides. The energy of the depositing species is controlled to maximize adhesion as well as to change the physical and chemical properties of the films. Adhesion is promoted by the creation of a graded interface between the film and the substrate. The energy of the depositing ions is also used to modify and control the intrinsic stresses and the microstructure of the films. The deposition is carried out at room temperature, which is important for temperature sensitive substrates. A correlation between intrinsic stresses and the energetics of the deposition is presented for the case of DLC films, and means to reduce stress levels are discussed.

An analysis has been carried out of natural circulation thermal hydraulics in both the primary and intermediate circuits of the Encapsulated Nuclear Heat Source (ENHS). It is established that natural circulation enhanced by gas injection into the primary coolant above the core, or the intermediate coolant above the heat exchange zone, is effective in transporting the nominal core power to the steam generators without the attainment of excessive system temperatures. Uncertainties in thermophysical properties and wall friction have a relatively small effect upon the calculated best estimate primary and intermediate coolant system temperature rises.

A major feature of the Magnox gas cooled reactor design is the graphite core, which acts as the moderator but also provides the physical structure for fuel, control rods, instrumentation and coolant gas channels. The lifetime of a graphite core is dependent upon two principal aging processes: irradiation damage and radiolytic oxidation. Irradiation damage from fast neutrons creates lattice defects leading to changes in physical and mechanical properties and the accumulation of stresses. Radiolytic oxidation is caused by the reaction of oxidizing species from the carbon dioxide coolant gas with the graphite, these species being produced by gamma radiation. Radiolytic oxidation reduces the density and hence the moderating capability of the graphite, but also reduces strength affecting the integrity of core components. In order to manage continued operation over the planned lifetimes of their power stations, BNFL needed to extend their database of the effects of these two phenomena on the ir graphite cores through an irradiation experiment. This paper will discuss the background, purpose, and the processes taken and planned (i.e. post irradiation examination) to ensure meaningful data on the graphite core material is obtained from the irradiation experiment.

The optical properties of wurtzite InN grown on sapphire substrates by molecular-beam epitaxy have been characterized by optical absorption, photoluminescence, and photomodulated reflectance techniques. All these three characterization techniques show an energy gap for InN between 0.7 and 0.8 eV, much lower than the commonly accepted value of 1.9 eV. The photoluminescence peak energy is found to be sensitive to the free electron concentration of the sample. The peak energy exhibits a very weak hydrostatic pressure dependence and a small, anomalous blueshift with increasing temperature. The bandgap energies of In-rich InGaN alloys were found to be consistent with the narrow gap of InN. The bandgap bowing parameter was determined to be 1.43 eV in InGaN.