Publications

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Over 300 Asian life scientists were surveyed to provide insight into work with infectious agents. This report provides the reader with a more complete understanding of the current practices employed to study infectious agents by laboratories located in Asian countries--segmented by level of biotechnology sophistication. The respondents have a variety of research objectives and study over 60 different pathogens and toxins. Many of the respondents indicated that their work was hampered by lack of adequate resources and the difficulty of accessing critical resources. The survey results also demonstrate that there appears to be better awareness of laboratory biosafety issues compared to laboratory biosecurity. Perhaps not surprisingly, many of these researchers work with pathogens and toxins under less stringent laboratory biosafety and biosecurity conditions than would be typical for laboratories in the West.

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Recent reduction of drinking water Maximum Concentration Level (MCL) for arsenic from 50 ppb to 10 ppb was intended to reduce incidence of bladder cancer and other cancers in US. Southwestern United States is characterized by high and variable background levels for arsenic. Estimated national annual costs of implementing 10 ppb MCL range from $165M to $605M to save 7 - 33 lives. - $5M - $23.9M /life saved - $1.3M - $6.6M/ year of life saved. About 1 life/500,000 exposed persons per year. New MCL is controversial due to high costs and uncertain health benefits.

Using a magnetic pressure drive, an absolute measurement of stress and density along the principal compression isentrope is obtained for solid aluminum to 240 GPa. Reduction of the free-surface velocity data relies on a backward integration technique, with approximate accounting for unknown systematic errors in experimental timing. Maximum experimental uncertainties are +/-4.7% in stress and +/-1.4% in density, small enough to distinguish between different equation-of-state (EOS) models. The result agrees well with a tabular EOS that uses an empirical universal zero-temperature isotherm.

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A simple solution synthesis of germanium (Ge{sup 0}) nanowires under mild conditions (<400 C and 1 atm) was demonstrated using germanium 2,6 dibutylphenoxide Ge(DBP){sub 2} (1) as the precursor where DBP = OC{sub 6}H{sub 3}(C(CH{sub 3}){sub 3}){sub 2}-2,6. Compound 1, synthesized from Ge(NR{sub 2}){sub 2} where R = SiMe{sub 3} and two equivalents of DBP-H, was characterized as a mononuclear species by single crystal X-ray diffraction. Dissolution of 1 in oleylamine, followed by rapid injection into a 1-octadecene solution heated to 300 C under an atmosphere of Ar, led to the formation of Ge{sup 0} nanowires. The Ge{sup 0} nanowires were characterized by transmission electron microscopy (TEM), X-ray diffraction analysis, and Fourier transform infrared spectroscopy. These characterizations revealed that the nanowires are single crystalline in the cubic phase and coated with oleylamine surfactant. We also observed that the nanowire length (0.1 to 10 {micro}m) increases with increasing temperature (285 to 315 C) and time (5 to 60 min). Two growth mechanisms are proposed based on the TEM images intermittently taken during the growth process as a function of time: (1) self-seeding mechanism where one of two overlapping nanowires serves as a seed, while the other continues to grow as a wire and (2) self-assembly mechanism where an aggregate of small rods (< 50 nm in diameter) recrystallize on the tip of a longer wire, extending its length.

This report evaluates a newly-available, high-definition, video camera coupled with a zoom optical system for microscopic imaging of micro-electro-mechanical systems. We did this work to support configuration of three document-camera-like stations as part of an installation in a new Microsystems building at Sandia National Laboratories. The video display walls to be installed as part of these three presentation and training stations are of extraordinary resolution and quality. The new availability of a reasonably-priced, cinema-quality, high-definition video camera offers the prospect of filling these displays with full-motion imaging of Sandia's microscopic products at a quality substantially beyond the quality of typical video microscopes. Simple and robust operation of the microscope stations will allow the extraordinary-quality imaging to contribute to Sandia's day-to-day research and training operations. This report illustrates the disappointing image quality from a camera/lens system comprised of a Sony HDC-X310 high-definition video camera coupled to a Navitar Zoom 6000 lens. We determined that this Sony camera is capable of substantially more image quality than the Navitar optic can deliver. We identified an optical doubler lens from Navitar as the component of their optical system that accounts for a substantial part of the image quality problem. While work continues to incrementally improve performance of the Navitar system, we are also evaluating optical systems from other vendors to couple to this Sony camera.

This paper summarizes the results of a theoretical and experimental program at Sandia National Laboratories aimed at identifying and modeling key physical features of rocks and rock-like materials at the laboratory scale over a broad range of strain rates. The mathematical development of a constitutive model is discussed and model predictions versus experimental data are given for a suite of laboratory tests. Concurrent pore collapse and cracking at the microscale are seen as competitive micromechanisms that give rise to the well-known macroscale phenomenon of a transition from volumetric compaction to dilatation under quasistatic triaxial compression. For high-rate loading, this competition between pore collapse and microcracking also seems to account for recently identified differences in strain-rate sensitivity between uniaxial-strain 'plate slap' data compared to uniaxial-stress Kolsky bar data. A description is given of how this work supports ongoing efforts to develop a predictive capability in simulating deformation and failure of natural geological materials, including those that contain structural features such as joints and other spatial heterogeneities.

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This SAND report provides the technical progress through April 2005 of the Sandia-led project, "Carbon Sequestration in Synechococcus Sp.: From Molecular Machines to Hierarchical Modeling," funded by the DOE Office of Science Genomics:GTL Program. Understanding, predicting, and perhaps manipulating carbon fixation in the oceans has long been a major focus of biological oceanography and has more recently been of interest to a broader audience of scientists and policy makers. It is clear that the oceanic sinks and sources of CO2 are important terms in the global environmental response to anthropogenic atmospheric inputs of CO2 and that oceanic microorganisms play a key role in this response. However, the relationship between this global phenomenon and the biochemical mechanisms of carbon fixation in these microorganisms is poorly understood. In this project, we will investigate the carbon sequestration behavior of Synechococcus Sp., an abundant marine cyanobacteria known to be important to environmental responses to carbon dioxide levels, through experimental and computational methods. This project is a combined experimental and computational effort with emphasis on developing and applying new computational tools and methods. Our experimental effort will provide the biology and data to drive the computational efforts and include significant investment in developing new experimental methods for uncovering protein partners, characterizing protein complexes, identifying new binding domains. We will also develop and apply new data measurement and statistical methods for analyzing microarray experiments. Computational tools will be essential to our efforts to discover and characterize the function of the molecular machines of Synechococcus. To this end, molecular simulation methods will be coupled with knowledge discovery from diverse biological data sets for high-throughput discovery and characterization of protein-protein complexes. In addition, we will develop a set of novel capabilities for inference of regulatory pathways in microbial genomes across multiple sources of information through the integration of computational and experimental technologies. These capabilities will be applied to Synechococcus regulatory pathways to characterize their interaction map and identify component proteins in these - 4 -pathways. We will also investigate methods for combining experimental and computational results with visualization and natural language tools to accelerate discovery of regulatory pathways. The ultimate goal of this effort is develop and apply new experimental and computational methods needed to generate a new level of understanding of how the Synechococcus genome affects carbon fixation at the global scale. Anticipated experimental and computational methods will provide ever-increasing insight about the individual elements and steps in the carbon fixation process, however relating an organism's genome to its cellular response in the presence of varying environments will require systems biology approaches. Thus a primary goal for this effort is to integrate the genomic data generated from experiments and lower level simulations with data from the existing body of literature into a whole cell model. We plan to accomplish this by developing and applying a set of tools for capturing the carbon fixation behavior of complex of Synechococcus at different levels of resolution. Finally, the explosion of data being produced by high-throughput experiments requires data analysis and models which are more computationally complex, more heterogeneous, and require coupling to ever increasing amounts of experimentally obtained data in varying formats. These challenges are unprecedented in high performance scientific computing and necessitate the development of a companion computational infrastructure to support this effort. More information about this project can be found at www.genomes-to-life.org Acknowledgment We want to gratefully acknowledge the contributions of: Grant Heffelfinger1*, Anthony Martino2, Brian Palenik6, Andrey Gorin3, Ying Xu10,3, Mark Daniel Rintoul1, Al Geist3, Matthew Ennis1, with Pratul Agrawal3, Hashim Al-Hashimi8, Andrea Belgrano12, Mike Brown1, Xin Chen9, Paul Crozier1, PguongAn Dam10, Jean-Loup Faulon2, Damian Gessler12, David Haaland1, Victor Havin4, C.F. Huang5, Tao Jiang9, Howland Jones1, David Jung3, Katherine Kang14, Michael Langston15, Shawn Martin1, Shawn Means1, Vijaya Natarajan4, Roy Nielson5, Frank Olken4, Victor Olman10, Ian Paulsen14, Steve Plimpton1, Andreas Reichsteiner5, Nagiza Samatova3, Arie Shoshani4, Michael Sinclair1, Alex Slepoy1, Shawn Stevens8, Charlie Strauss5, Zhengchang Su10, Ed Thomas1, Jerilyn Timlin1, WimVermaas13, Xiufeng Wan11, HongWei Wu10, Dong Xu11, Grover Yip8, Erik Zuiderweg8 *Author to whom correspondence should be addressed (gsheffe@sandia.gov) 1. Sandia National Laboratories, Albuquerque, NM 2. Sandia National Laboratories, Livermore, CA 3. Oak Ridge National Laboratory, Oak Ridge, TN 4. Lawrence Berkeley National Laboratory, Berkeley, CA 5. Los Alamos National Laboratory, Los Alamos, NM 6. University of California, San Diego 7. University of Illinois, Urbana/Champaign 8. University of Michigan, Ann Arbor 9. University of California, Riverside 10. University of Georgia, Athens 11. University of Missouri, Columbia 12. National Center for Genome Resources, Santa Fe, NM 13. Arizona State University 14. The Institute for Genomic Research 15. University of Tennessee 5 Sandia is a multiprogram laboratory operated by Sandia Corporation, a Lockheed Martin Company, for the United States Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL8500.

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The response of microsystem components to laser irradiation is relevant to the use of laser processing, optical diagnostics, and optical microelectromechanical systems (MEMS) device design and performance. The dimensions of MEMS are on the same order as infrared laser wavelengths which results in interference phenomena when the parts are partially transparent. Four distinct polycrystalline structures were designed and irradiated with 808 nm laser light to determine the effect of layers and the presence of a substrate via on the laser power threshold for damage. The presence of a substrate via resulted in lower damage thresholds, and interference phenomena resulted in a single layer structure having the highest damage threshold.

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