The post-genomic era presents new opportunities for manipulating plant chemistry for improvement of plant traits such as disease and stress resistance and nutritional qualities. This conference will provide a setting for developing multidisciplinary collaborations needed to unravel the dynamic complexity of plant metabolic networks and advance basic and applied research in plant metabolic engineering. The conference will integrate recent advances in genomics, with metabolite and gene expression analyses. Research discussions will explore how biosynthetic pathways interact with regard to substrate competition and channeling, plasticity of biosynthetic enzymes, and investigate the localization, structure, and assembly of biosynthetic metabolons in native and nonnative environments. The meeting will develop new perspectives for plant transgenic research with regard to how transgene expression may influence cellular metabolism. Incorporation of spectroscopic approaches for metabolic profiling and flux analysis combined with mathematical modeling will contribute to the development of rational metabolic engineering strategies and lead to the development of new tools to assess temporal and subcellular changes in metabolite pools. The conference will also highlight new technologies for pathway engineering, including use of heterologous systems, directed enzyme evolution, engineering of transcription factors and application of molecular/genetic techniques for controlling biosynthetic pathways.

Algebraic sub-structuring refers to the process of applying matrix reordering and partitioning algorithms to divide a large sparse matrix into smaller submatrices from which a subset of spectral components are extracted and combined to form approximate solutions to the original problem. In this paper, they show that algebraic sub-structuring can be effectively used to solve generalized eigenvalue problems arising from the finite element analysis of an accelerator structure.

We present a preliminary search for D{sup 0}-{bar D}{sup 0} mixing using the decays D{sup 0} {yields} K{sup +}{pi}{sup -}{pi}{sup 0}, additionally presenting Dalitz-plot distributions and a measurement of the branching ratio for this mode. A new tagging technique is used to produce the doubly Cabibbo-suppressed Dalitz plot, which in turn is used to motivate the method used for the D-mixing search. We analyze 230.4 fb{sup -1} of data collected from the BABAR detector at the PEP-II collider. Assuming CP conservation, we find R{sub M} < 0.054% with 95% confidence, and we estimate that the data are consistent with no mixing at a 4.5% confidence level. We present D-mixing results both with and without the assumption of CP conservation.

THE PHENOMENA IDENTIFICATION AND RANKING TECHNIQUE (PIRT) IS A SYSTEMATIC WAY OF GATHERING INFORMATION FROM EXPERTS ON A SPECIFIC SUBJECT, AND RANKING THE IMPORTANCE OF THE INFORMATION, IN ORDER TO MEET SOME DECISION MAKING OBJECTIVE. IT HAS BEEN APPLIED TO MANY NUCLEAR TECHONLOGY ISSUES INCLUDING NUCLEAR ANALYSIS IN ORDER TO HELP GUIDE RESEARCH OR DEVELOP REGULATORY REQUIREMENTS.

Double-shell (DS) targets (Amendt, P. A. et al., 2002) offer a complementary approach to the cryogenic baseline design (Lindl, J. et al., 2004) for achieving ignition on the National Ignition Facility (NIF). Among the expected benefits are the ease of room temperature preparation and fielding, the potential for lower laser backscatter and the reduced need for careful shock timing. These benefits are offset, however, by demanding fabrication tolerances, e.g., shell concentricity and shell surface smoothness. In particular, the latter is of paramount importance since DS targets are susceptible to the growth of interface perturbations from impulsive and time-dependent accelerations. Previous work (Milovich, J. L. et al., 2004) has indicated that the growth of perturbations on the outer surface of the inner shell is potentially disruptive. To control this instability new designs have been proposed requiring bimetallic inner shells and material-matching mid-Z nanoporous foam. The challenges in manufacturing such exotic foams have led to a further evaluation of the densities and pore sizes needed to reduce the seeding of perturbations on the outer surface of the inner shell, thereby guiding the ongoing material science research efforts. Highly-resolved 2D simulations of porous foams have been performed to establish an upper limit on …

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CALPHAD assessment of the thermodynamic properties of a series of Pu-based alloys is briefly presented together with some results on the kinetics of phase formation and transformations in Pu-Ga alloys.

In today's world, the use of parallel programming and architectures is essential for simulating practical problems in engineering and related disciplines. Remarkable progress in CPU architecture, system scalability, and interconnect technology continues to provide new opportunities, as well as new challenges for both system architects and software developers. These trends are paralleled by progress in parallel algorithms, simulation techniques, and software integration from multiple disciplines. ParSim brings together researchers from both application disciplines and computer science and aims at fostering closer cooperation between these fields. Since its successful introduction in 2002, ParSim has established itself as an integral part of the EuroPVM/MPI conference series. In contrast to traditional conferences, emphasis is put on the presentation of up-to-date results with a short turn-around time. This offers a unique opportunity to present new aspects in this dynamic field and discuss them with a wide, interdisciplinary audience. The EuroPVM/MPI conference series, as one of the prime events in parallel computation, serves as an ideal surrounding for ParSim. This combination enables the participants to present and discuss their work within the scope of both the session and the host conference. This year, eleven papers from authors in nine countries were submitted to ParSim, and …

An overview of the Pulse Line Ion Accelerator (PLIA) concept and its development is presented. In the PLIA concept a pulse power driver applied to one end of a helical pulse line creates a traveling wave pulse that accelerates and axially confines a heavy ion beam pulse The motivation for its development at the IFE-VNL is the acceleration of intense, short pulse, heavy ion beams to regimes of interest for studies of High Energy Density Physics and Warm Dense Matter. Acceleration scenarios with constant parameter helical lines are described which result in output energies of a single stage much larger than the several hundred kilovolt peak voltages on the line, with a goal of 3-5 MeV/meter acceleration gradients. The main attraction of the concept is the very low cost it promises. It might be described crudely as an ''air core'' induction linac where the pulse-forming network is integrated into the beam line so the accelerating voltage pulse can move along with the ions to get voltage multiplication.

A fracture within a porous background is modeled as a thin porous layer with increased compliance and finite permeability. For small layer thickness, a set of boundary conditions can be derived that relate particle velocity and stress across a fracture, induced by incident poroelastic waves. These boundary conditions are given via phenomenological parameters that can be used to examine and characterize the seismic response of a fracture. One of these parameters, here it is called membrane permeability, is shown through several examples to control the scattering amplitude of the slow P waves for very low-permeability fractures, which in turn controls the intrinsic attenuation of the waves.

Along the remote shores of the Columbia River in southeast Washington state, a race is on. Fluor Hanford, a prime cleanup contractor to the U.S. Department of Energy (DOE) at the Hanford Site, is managing a massive, multi-faceted project to remove contaminants from the groundwater before they can reach the Columbia. Despite the daunting nature and size of the problem--about 80 square miles of aquifer under the site contains long-lived radionuclides and hazardous chemicals--significant progress is being made. Many groups are watching, speaking out, and helping. A large. passionate, diverse, and geographically dispersed community is united in its desire to protect the Columbia River--the eighth largest in the world--and have a voice in Hanford's future. Fluor Hanford and the DOE, along with the US. Environmental Protection Agency (EPA) and the Washington Department of Ecology (Ecology) interact with all the stakeholders to make the best decisions. Together, they have made some remarkable strides in the battle against groundwater contamination under the site.

This paper investigates how critical-peak pricing (CPP)affects households with different usage and income levels, with the goalof informing policy makers who are considering the implementation of CPPtariffs in the residential sector. Using a subset of data from theCalifornia Statewide Pricing Pilot of 2003-2004, average load changeduring summer events, annual percent bill change, and post-experimentsatisfaction ratings are calculated across six customer segments,categorized by historical usage and income levels. Findings show thathigh-use customers respond significantly more in kW reduction than dolow-use customers, while low-use customers save significantly more inpercentage reduction of annual electricity bills than do high-usecustomers results that challenge the strategy of targeting only high-usecustomers for CPP tariffs. Across income levels, average load and billchanges were statistically indistinguishable, as were satisfaction ratesresults that are compatible with a strategy of full-scale implementationof CPP rates in the residential sector. Finally, the high-use customersearning less than $50,000 annually were the most likely of the groups tosee bill increases about 5 percent saw bill increases of 10 percent ormore suggesting that any residential CPP implementation might considertargeting this customer group for increased energy efficiencyefforts.

The homogeneous charge compression ignition (HCCI) engine is an attractive technology because of its high efficiency and low emissions. However, HCCI lacks a direct combustion trigger making control of combustion timing challenging, especially during transients. To aid in HCCI engine control we present a simple model of the HCCI combustion process valid over a range of intake pressures, intake temperatures, equivalence ratios, and engine speeds. The model provides an estimate of the combustion timing on a cycle-by-cycle basis. An ignition threshold, which is a function of the in-cylinder motored temperature and pressure is used to predict start of combustion. This model allows the synthesis of nonlinear control laws, which can be utilized for control of an HCCI engine during transients.

We introduce a new thermodynamic theory for detonation products that includes polar and ionic species. The new formalism extends the domain of validity of the previously developed EXP6 equation of state library and opens the possibility of new applications. We illustrate the scope of the new approach on PETN detonation properties and water ionization models.

On behalf of the BABAR and Belle collaborations, the authors report on the measurement of the angle {gamma} and of the sum of angles 2{beta} + {gamma} of the Unitarity Triangle.

Sequence changes in regulatory regions have often beeninvoked to explain phenotypic divergence among species, but molecularexamples of this have been difficult to obtain. In this study, weidentified an anthropoid primate specific sequence element thatcontributed to the regulatory evolution of the LDL receptor. Using acombination of close and distant species genomic sequence comparisonscoupled with in vivo and in vitro studies, we show that a functionalcholesterol-sensing sequence motif arose and was fixed within apre-existing enhancer in the common ancestor of anthropoid primates. Ourstudy demonstrates one molecular mechanism by which ancestral mammalianregulatory elements can evolve to perform new functions in the primatelineage leading to human.

We have developed a mixed Vector Finite Element Method (VFEM) for Maxwell's equations with a nonlinear polarization term. The method allows for discretization of complicated geometries with arbitrary order representations of the B and E fields. In this paper we will describe the method and a series of optimizations that significantly reduce the computational cost. Additionally, a series of test simulations will be presented to validate the method. Finally, a nonlinear waveguide mode mixing example is presented and discussed.

This work is motivated by the growing interest in injectingcarbon dioxide into deep geological formations as a means of avoidingatmospheric emissions of carbon dioxide and consequent global warming.One of the key questions regarding the feasibility of this technology isthe potential rate of leakage out of the primary storage formation. Weseek exact solutions in a model of gas flow driven by a combination ofbuoyancy, viscous and capillary forces. Different combinations of theseforces and characteristic length scales of the processes lead todifferent time scaling and different types of solutions. In the case of athin, tight seal, where the impact of gravity is negligible relative tocapillary and viscous forces, a Ryzhik-type solution implies square-rootof time scaling of plume propagation velocity. In the general case, a gasplume has two stable zones, which can be described by travelling-wavesolutions. The theoretical maximum of the velocity of plume migrationprovides a conservative estimate for the time of vertical migration.Although the top of the plume has low gas saturation, it propagates witha velocity close to the theoretical maximum. The bottom of the plumeflows significantly more slowly at a higher gas saturation. Due to localheterogeneities, the plume can break into parts. Individual plumes alsocan coalesce and from larger plumes. The …

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Future high-energy accelerators such as the Next Linear Collider (NLC) will accelerate multi-bunch beams of high current and low emittance to obtain high luminosity, which put stringent requirements on the accelerating structures for efficiency and beam stability. While numerical modeling has been quite standard in accelerator R&D, designing the NLC accelerating structure required a new simulation capability because of the geometric complexity and level of accuracy involved. Under the US DOE Advanced Computing initiatives (first the Grand Challenge and now SciDAC), SLAC has developed a suite of electromagnetic codes based on unstructured grids and utilizing high performance computing to provide an advanced tool for modeling structures at accuracies and scales previously not possible. This paper will discuss the code development and computational science research (e.g. domain decomposition, scalable eigensolvers, adaptive mesh refinement) that have enabled the large-scale simulations needed for meeting the computational challenges posed by the NLC as well as projects such as the PEP-II and RIA. Numerical results will be presented to show how high performance computing has made a qualitative improvement in accelerator structure modeling for these accelerators, either at the component level (single cell optimization), or on the scale of an entire structure (beam heating and …

Shock initiation experiments were performed on the plastic bonded explosive (PBX) LX-04 (85% HMX, 15% Viton binder) using single and multiple low amplitude shocks to obtain pressure history data for use in Ignition and Growth reactive flow modeling parameterization. A 100 mm diameter propellant driven gas gun was utilized to initiate the LX-04 explosive charges containing manganin piezoresistive pressure gauge packages placed between explosive discs. In the single shock experiments, the run distances to detonation at three shock pressures showed agreement with previously published data above 3 GPa. Even longer run distances to detonation were measured using 80 mm long by 145 mm diameter LX-04 charges impacted by low velocity projectiles from a 155 mm diameter gun. The minimum shock pressure required to cause low levels of exothermic reaction were determined for these large LX-04 charge dimensions. Multiple shocks were generated as double shocks by using a flyer plate with two materials and as reflected shocks by placing a high impedance material at the rear of the explosive charge. In both cases, the first shock pressure was not high enough to cause detonation of LX-04, and the second shock pressure, which would have been sufficient to cause detonation if generated …

Protein microarrays in which proteins are immobilized to a solid surface are ideal reagents for high-throughput experiments that require very small amounts of analyte. Such protein microarrays (''protein chips'') can be used very efficiently to analyze all kind of protein interactions en masse. Although a variety of methods are available for attaching proteins on solid surfaces. Most of them rely on non-specific adsorption methods or on the reaction of chemical groups within proteins (mainly, amino and carboxylic acid groups) with complementary reactive groups. In both cases the protein is attached to the surface in random orientations. The use of recombinant affinity tags addresses the orientation issue, however in most of the cases the interaction of the tags are reversible (e.g., glutathione S-transferase, maltose binding protein and poly-His) and, hence, are not stable over the course of subsequent assays or require large mediator proteins (e.g., biotin-avidin and antigen antibody). The key for the covalent attachment of a protein to a solid support with a total control over the orientation is to introduce two unique and mutually reactive groups on both the protein and the surface. The reaction between these two groups should be highly selective thus behaving like a molecular ''velcro''.

Initiation of insensitive high explosives is affected by porosity in the 100 nm to micron size range. It is also recognized that as-pressed plastic bonded explosives (PBX) are heterogeneous in composition and density at much coarser length scale (10 microns-100 microns). However, variations in density and composition of these explosives have been poorly characterized. Here, we characterize the natural variations in composition and density of TATB-based PBX LX-17 with synchrotron radiation tomography and ultra small angle x-ray scattering. Large scale variations in composition occur as a result of binder enrichment at the prill particle boundaries. The pore fraction is twice as high in the prill particle as in the boundary. The pore distribution is bimodal, with small pores of 50-100 nm in radius and a broader distribution of pores in the 0.5-1.5 micron size range. The higher pore density within the prill particle is attributed to contact asperities between the crystallites that might inhibit complete consolidation and binder infiltration.

Isopiestic vapor pressure measurements were made for (xZnCl{sub 2} + (1 - x)ZnSO{sub 4})(aq) solutions with ZnCl{sub 2} molality fractions of x = (0, 0.3062, 0.5730, 0.7969, and 1) at the temperature 298.15 K, using KCl(aq) as the reference standard. These measurements cover the water activity range 0.901-0.919 {le} a{sub w} {le} 0.978. The experimental osmotic coefficients were used to evaluate the parameters of an extended ion-interaction (Pitzer) model for these mixed electrolyte solutions. A similar analysis was made of the available activity data for ZnCl{sub 2}(aq) at 298.15 K, while assuming the presence of equilibrium amounts of ZnCl{sup +}(aq) ion-pairs, to derive the ion-interaction parameters for the hypothetical pure binary electrolytes (Zn{sup 2+}, 2Cl{sup -}) and (ZnCl{sup +},Cl{sup -}). These parameters are required for the analysis of the mixture results. Although significant concentrations of higher-order zinc chloride complexes may also be present in these solutions, it was possible to represent the osmotic coefficients accurately by explicitly including only the predominant complex ZnCl{sup +}(aq) and the completely dissociated ions. The ionic activity coefficients and osmotic coefficients were calculated over the investigated molality range using the evaluated extended Pitzer model parameters.