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The objective of this proposal was twofold. First, upgrade existing MRI equipment, specifically a research 4.1T whole-body system. Second, purchase a clinical, state-of-the-art 3T MRI system tailored specifically to cardiovascular and neurological applications. This project was within the guidelines of ''Medical Applications and Measurement Science''. The goals were: [1] to develop beneficial applications of magnetic resonance imaging; [2] discover new applications of MR strategies for medical research; and [2] apply them for clinical diagnosis. Much of this proposal searched for breakthroughs in this noninvasive and nondestructive imaging technology. Finally, this proposal's activities focused on research in the basic science of chemistry, biochemistry, physics, and engineering as applied to bioengineering. The centerpiece of this grant was our 4.1T ultra-high field whole-body nuclear magnetic resonance system and the newly acquired state-of-the-art, heart and head dedicated 3T clinical MRI system. We have successfully upgraded the equipment for the 4.1T system so that it is now state-of-the-art with new gradient and radio frequency amplifiers. We also purchase a unique In Vivo EKG monitoring unit that will permit tracking clinical quality EKG signals while the patient is in a high field MR scanner. Important upgrades of a peripheral vascular coil and a state-of-the-art clinical workstation …

We have utilized computational molecular modeling to generate a state-of-the-art large scale structural representation of a bituminous coal of lower bituminous rank. This structure(s) has been used to investigate the molecular forces between the bituminous coal structure (or idealized pores) and the molecular species CH{sub 4} and CO{sub 2}. We have created a new force field for these simulations and are currently carrying out molecular dynamics simulations. An initial step performed is to help define the issues with sequestration utilizing the molecular modeling approach. Once defined advanced molecular modeling techniques can be utilized in investigating sorbent and host behavior.

RAD51 proteins accumulate in discrete nuclear foci in response to DNA damage. Previous studies demonstrated that human RAD51 paralogs (RAD51B, RAD51C, RAD51D, XRCC2 and XRCC3) are essential for the assembly of RAD51 foci induced by ionizing radiation and cross-linking agents. Here we report that XRCC2 also plays important roles in RAD51 focus formation induced by replication arrest during S-phase of cell cycle. In wild-type hamster V79 cells treated with hydroxyurea (HU), RAD51 protein form punctuate nuclear foci, accompanied by increased RAD51 protein level in both cytoplasmic and nuclear fractions, and increased association of RAD51 with chromatin. In contrast, xrcc2 hamster mutant irs1 cells are deficient in the formation of RAD51 foci after HU treatment, suggesting that the function of XRCC2 is required for the assembly of RAD51 at HU-induced stalled replication forks. Interestingly, we found that irs1 cells are able to form intact RAD51 foci in S-phase cells treated with thymidine (TR) or aphidicolin, although irs1 cells are hypersensitive to both HU and TR. Our findings suggest that there may be two distinct pathways (XRCC2-dependent or XRCC2-independent) involved in loading of RAD51 onto stalled replication forks, probably depending upon the structure of DNA lesions.

The knowledge of how to ventilate buildings, and how much ventilation is necessary for human health and comfort, has evolved over centuries of trial and error. Humans and animals have developed successful solutions to the problems of regulating temperature and removing air pollutants through the use of ventilation. These solutions include ingenious construction methods, such as engineered passive ventilation (termite mounds and passive stacks), mechanical means (wing-powered, fans), and an evolving effort to identify problems and develop solutions. Ventilation can do more than help prevent building occupants from getting sick; it can provide an improved indoor environment. Codes and standards provide minimum legal requirements for ventilation, but the need for ventilation goes beyond code minima. In this paper we will look at indoor air pollutant sources over time, the evolution of ventilation strategies, current residential ventilation codes and standards (e.g., recently approved ASHRAE Standard 62.2), and briefly discuss ways in which we can go beyond the standards to optimize residential ventilation, reduce indoor air quality problems, and provide corresponding social and economic benefit.

According to the U.S. Department of Energy, electricity use by non-PC commercial office equipment is growing at an annual rate of nearly 5 percent (AEO 2003). To help address this growth in consumption, U.S. EPA periodically updates its ENERGY STAR specifications as products and markets change. This report presents background research conducted to help EPA update the ENERGY STAR specification for imaging equipment, which covers printers, fax machines, copiers, scanners, and multifunction devices (MFDs). We first estimated the market impact of the current ENERGY STAR imaging specification, finding over 90 percent of the current market complies with the specification. We then analyzed a sample of typical new imaging products, including 11 faxes, 57 printers and 19 copiers/MFD. For these devices we metered power levels in the most common modes: active/ready/sleep/off, and recorded features that would most likely affect energy consumption. Our metering indicates that for many products and speed bins, current models consume substantially less power than the current specification. We also found that for all product categories, power consumption varied most considerably across technology (i.e. inkjet vs. laser). Although inkjet printers consumed less energy than laser printers in active, ready and sleep-mode, they consumed more power on average while …

This project's goal is to develop remote sensing methods for early detection and spatial mapping, over whole regions simultaneously, of any surface areas under which there are significant CO2 leaks from deep underground storage formations. If large amounts of CO2 gas percolated up from a storage formation below to within plant root depth of the surface, the CO2 soil concentrations near the surface would become elevated and would affect individual plants and their local plant ecologies. Excessive soil CO2 concentrations are observed to significantly affect local plant and animal ecologies in our geothermal exploration, remote sensing research program at Mammoth Mountain CA USA. We also know from our geothermal exploration remote sensing programs, that we can map subtle hidden faults by spatial signatures of altered minerals and of plant species and health distributions. Mapping hidden faults is important because in our experience these highly localized (one to several centimeters) spatial pathways are good candidates for potentially significant CO2 leaks from deep underground formations. The detection and discrimination method we are developing uses primarily airborne hyperspectral, high spatial (3 meter) with 128 band wavelength resolution, visible and near infrared reflected light imagery. We also are using the newly available ''Quickbird'' satellite …

The Schroedinger equation is solved in time and space to implement a finite-temperature equation-of-state theory for dense, partially ionized matter. The time-dependent calculation generates a spectrum of quantum states. Eigenfunctions are calculated from a knowledge of the spectrum and used to calculate the electronic pressure and energy. Results are given for LID and compared with results from the INFERNO model.

For representing the source-term of a proposed repository at Yucca Mountain, NV, total system performance assessment models evaluate the disequilibrium degradation of the waste forms to capture a bounding rate for radionuclide source-term availability and use solubility constraints that are more representative of longer-term, equilibrium processes to limit radionuclide mass transport from the source-term. These solubility limits capture precipitation processes occurring either as the waste forms alter, or in the near-field environment as chemical conditions evolve. A number of alternative models for solubility controls on dissolved neptunium concentrations have been evaluated. These include idealized models based on precipitation of neptunium as separate oxide minerals and more complex considerations of trace amounts of neptunium being incorporated into the secondary uranyl phases from waste form alteration. Thermodynamic models for neptunium under oxidizing conditions indicate that tetravalent neptunium (NpO{sub 2}) solids are more stable relative to pentavalent (Np{sub 2}O{sub 5}) phases, and thereby set lower dissolved concentrations of neptunyl species. Data on solids and solutions from slow flow through (dripping) tests on spent fuel grains indicate that neptunium is tetravalent in the spent fuel and that over {approx}9 years the neptunium concentrations are near to or below calculated NpO{sub 2} solubility. The possibility …

A number of 7xx aluminum casting alloys are based on the ternary Al-Zn-Mg system. These alloys age naturally to high strength at room temperature. A high temperature solution and aging treatment is not required. Consequently, these alloys have the potential to deliver properties nearly equivalent to conventional A356-T6 (Al-Si-Mg) castings, with a significant cost saving. An energy savings is also possible. In spite of these advantages, the 7xx casting alloys are seldom used, primarily because of their reputation for poor castibility. This paper describes the results obtained in a DOE-funded research study of these alloys, which is part of the DOE-OIT ''Cast Metals Industries of the Future'' Program. Suggestions for possible commercial use are also given.

The simultaneous diffusion of Si and the dopants B, P, and As has been studied by the use of a multilayer structure of isotopically enriched Si. This structure, consisting of 5 pairs of 120 nm thick natural Si and {sup 28}Si enriched layers, enables the observation of {sup 30}Si self-diffusion from the natural layers into the {sup 28}Si enriched layers, as well as dopant diffusion from an implanted source in an amorphous Si cap layer, via Secondary Ion Mass Spectrometry (SIMS). The dopant diffusion created regions of the multilayer structure that were extrinsic at the diffusion temperatures. In these regions, the Fermi level shift due to the extrinsic condition altered the concentration and charge state of the native defects involved in the diffusion process, which affected the dopant and self-diffusion. The simultaneously recorded diffusion profiles enabled the modeling of the coupled dopant and self-diffusion. From the modeling of the simultaneous diffusion, the dopant diffusion mechanisms, the native defect charge states, and the self- and dopant diffusion coefficients can be determined. This information is necessary to enhance the physical modeling of dopant diffusion in Si. It is of particular interest to the modeling of future electronic Si devices, where the nanometer-scale …

A new disposal well was drilled in the vicinity of an injection well that had been in operation for 12 years. The drilling activities provided an opportunity to assess the fate and transport of waste products injected in the nearby well, and the impact, if any, on the host geologic formation. The origin of the fluid collected while drilling the new well and the interaction between injected waste and the formation were investigated using analyses of formation waters, waste, and formation minerals, by applying traditional graphical methods and sophisticated numerical models. This approach can be used to solve a wide range of geochemical problems related to deep well injection of waste. Trilinear Piper diagrams, Stiff diagrams, and correlation plots show that the chemical characteristics of recovered fluid at the new well are similar to those of formation water. The concentrations of most major constituents in the fluid appear diluted when compared to formation water sampled at other locations. This could be explained by mixing with waste, which is less saline than formation water. However, the waste injected near the new well consists primarily of ammonia and sulfate, and these waste constituents are not found at concentrations elevated enough to suggest …

The LLNL near-field hydrologic source term (HST) model is based on a mechanistic approach to radionuclide retardation-that is, a thermodynamic description of chemical processes governing retardation in the near field, such as aqueous speciation, surface complexation, ion exchange, and precipitation The mechanistic approach allows for radionuclide retardation to vary both in space and time as a function of the complex reaction chemistry of the medium. This level of complexity is necessary for near-field HST transport modeling because of the non-linear reaction chemistry expected close to the radiologic source. Large-scale Corrective Action Unit (CAU) models-into which the near-field HST model results feed-require that the complexity of the mechanistic approach be reduced to a more manageable form (e.g. Linear, Langmuir, or Freundlich sorption isotherms, etc). The linear sorption isotherm (or K{sub d}) approach is likely the most simple approach for large-scale CAU models. It may also be the most appropriate since the reaction chemistry away from the near field is expected to be less complex and relatively steady state. However, if the radionuclide retardation approaches in near-field HST and large-scale CAU models are different, they must be proved consistent. In this report, we develop a method to link the near-field HST and …