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Terrestrial ecosystem responses to global change: A research strategy

Description: Uncertainty about the magnitude of global change effects on terrestrial ecosystems and consequent feedbacks to the atmosphere impedes sound policy planning at regional, national, and global scales. A strategy to reduce these uncertainties must include a substantial increase in funding for large-scale ecosystem experiments and a careful prioritization of research efforts. Prioritization criteria should be based on the magnitude of potential changes in environmental properties of concern to society, including productivity; biodiversity; the storage and cycling of carbon, water, and nutrients; and sensitivity of specific ecosystems to environmental change. A research strategy is proposed that builds on existing knowledge of ecosystem responses to global change by (1) expanding the spatial and temporal scale of experimental ecosystem manipulations to include processes known to occur at large scales and over long time periods; (2) quantifying poorly understood linkages among processes through the use of experiments that manipulate multiple interacting environmental factors over a broader range of relevant conditions than did past experiments; and (3) prioritizing ecosystems for major experimental manipulations on the basis of potential positive and negative impacts on ecosystem properties and processes of intrinsic and/or utilitarian value to humans and on feedbacks of terrestrial ecosystems to the atmosphere.
Date: September 1, 1998
Partner: UNT Libraries Government Documents Department

Calculations on Cylindrical Metal Vacuum Chambers in Pulsed Magnetic Fields

Description: It has been suggested that metallic vacuum chambers might be suitable for pulsed magnets operating at audio frequencies, with pulse widths nominally 1/360 sec. In the present note calculations are given for a simple model of such a system, in order to estimate the effects of field attenuation and eddy current losses. The results of the calculation may be summarized briefly as follows, where the results apply to a cylindrical chamber of non-maeyletic stainless steel, 3.0 cm in inside diameter and 0.15 an wall thickness: (1) With steady-state harmonic excitation, the field in the interior Is reduced by a factor of {approximately} 1.03 at 2,000 cps compared to dc; (2) With transient operation, the exponential decay time is about 0.021 millisecond; (3) With square-wave excitation, at 200 gauss and 180 pps, the power dissipation in the stainless steel is about 24 watts/foot, or about a factor of 20 less if half-sine-wave pulses are used instead of square pulses. These results seem encouraging enough to warrant experimental investigation of this type of vacuum chamber for pulsed steering.
Date: October 8, 1964
Partner: UNT Libraries Government Documents Department

Specific application for Oak Ridge National Laboratory dismantlement of Building 3004. Appendix A -- Quality assurance plan; Appendix B -- Records management plan

Description: This quality assurance (QA) plan defines the QA requirements for the dismantlement and removal of Building 3004 at Oak Ridge National Laboratory (ORNL). The building is a four-story wooden trained structure with wooden siding, which resides approximately 150 ft west of the Bulk Shielding Reactor, and only several feet away from the visitors entrance to the Graphite Reactor museum. Complete descriptions and sketches are in the Performance Specification document for this project. This project is being conducted as a non-CERCLA maintenance action. This plan is an appendix to the QA plan for the ORNL Environmental Restoration (ER) Program. ORNL/ER-225, which is the source of the project QA requirements, tailors those QA requirements to the specific needs of this project as defined in ORNL/ER-225. Project-specific description and organization are also provided in this plan. Appendix B, Records Management Plan, is included.
Date: March 1, 1997
Partner: UNT Libraries Government Documents Department

Partnering for functional genomics research conference: Abstracts of poster presentations

Description: This reports contains abstracts of poster presentations presented at the Functional Genomics Research Conference held April 16--17, 1998 in Oak Ridge, Tennessee. Attention is focused on the following areas: mouse mutagenesis and genomics; phenotype screening; gene expression analysis; DNA analysis technology development; bioinformatics; comparative analyses of mouse, human, and yeast sequences; and pilot projects to evaluate methodologies.
Date: June 1, 1998
Partner: UNT Libraries Government Documents Department

Dynamical relativistic effects in quasielastic 1 {rho}-shell proton knockout from {sup 16}O

Description: The authors have measured the cross section for quasielastic 1 {rho}-shell proton knockout in the (sup 16)O (e, e{prime}p) reaction at {omega} = 0.439 GeV and Q{sup 2} = 0.8 (GeV/c){sup 2} for missing momentum P{sub miss} {<=} 355 MeV/c. They have extracted the response functions R{sub L+TT}, R{sub T}, R{sub LT}, and the left-right asymmetry, A{sub LT}, for the 1{rho}{sub 1/2} and the 1{rho}{sub 3/2} states. The data are well described by relativistic distorted wave impulse approximation calculations. At large P{sub miss}, the structure observed in A{sub LT} indicates the existence of dynamical relativistic effects.
Date: July 1999
Partner: UNT Libraries Government Documents Department

Photoproduction of phi(1020) Mesons on the Proton at Large Momentum Transfer.

Description: The cross-section for phi meson photoproduction on the proton has been measured for the first time up to a four-momentum transfer t=-4 GeV{sup 2}, using the CLAS detector at the Thomas Jefferson National Accelerator Facility. At low four-momentum transfer, the differential cross section is well-described by Pomeron exchange. At large four-momentum transfer, above -t=1.8 GeV{sup 2}, the data support a model where the Pomeron is resolved into its simplest component, two gluons, which may couple to any quark in the proton and in the phi.
Date: June 1, 2000
Partner: UNT Libraries Government Documents Department

Tests of quark mass textures

Description: The classic hints on the structure of the quark mass matrices are shortly reviewed and the possibility of obtaining further information through precise texture analysis is discussed with the aid of a specific example.
Date: December 21, 2000
Partner: UNT Libraries Government Documents Department

Topcolor

Description: We review a class of dynamical models in which top condensation occurs at the weak scale, giving rise to the large top quark mass and other phenomena. This typically requires a color embedding, SU(3){sub c} {yields} SU(3){sub 1} x SU(3){sub 2}, ergo ``Topcolor.`` Topcolor suggests a novel route to technicolor models in which sequential quarks condense under the Topcolor interaction to break electroweak symmetries.
Date: November 1, 1996
Partner: UNT Libraries Government Documents Department

A beamline matching application based on open source software

Description: An interactive Beamline Matching application has been developed using beamline and automatic differentiation class libraries. Various freely available components were used; in particular, the user interface is based on FLTK, a C++ toolkit distributed under the terms of the GNU Public License (GPL). The result is an application that compiles without modifications under both X-Windows and Win32 and offers the same look and feel under both operating environments. In this paper, we discuss some of the practical issues that were confronted and the choices that were made. In particular, we discuss object-based event propagation mechanisms, multithreading, language mixing and persistence.
Date: December 21, 2000
Partner: UNT Libraries Government Documents Department

Pacific Northwest Laboratory: Director`s overview of research performed for DOE Office of Health And Environmental Research

Description: A significant portion of the research undertaken at Pacific Northwest Laboratory (PNL) is focused on the strategic programs of the US Department of Energy`s (DOE) Office of Health and Environmental Research (OHER). These programs, which include Environmental Processes (Subsurface Science, Ecosystem Function and Response, and Atmospheric Chemistry), Global Change (Climate Change, Environmental Vulnerability, and Integrated Assessments), Biotechnology (Human Genome and Structural Biology), and Health (Health Effects and Medical Applications), have been established by OHER to support DOE business areas in science and technology and environmental quality. PNL uses a set of critical capabilities based on the Laboratory`s research facilities and the scientific and technological expertise of its staff to help OHER achieve its programmatic research goals. Integration of these capabilities across the Laboratory enables PNL to assemble multidisciplinary research teams that are highly effective in addressing the complex scientific and technical issues associated with OHER-sponsored research. PNL research efforts increasingly are focused on complex environmental and health problems that require multidisciplinary teams to address the multitude of time and spatial scales found in health and environmental research. PNL is currently engaged in research in the following areas for these OHER Divisions: Environmental Sciences -- atmospheric radiation monitoring, climate modeling, carbon cycle, atmospheric chemistry, ecological research, subsurface sciences, bioremediation, and environmental molecular sciences; Health Effects and Life Sciences -- cell/molecular biology, and biotechnology; Medical Applications and Biophysical Research -- analytical technology, and radiological and chemical physics. PNL`s contributions to OHER strategic research programs are described in this report.
Date: June 1, 1995
Partner: UNT Libraries Government Documents Department

Modeling and simulation support for ICRF heating of fusion plasmas. Annual report, 1990

Description: Recent experimental, theoretical and computational results have shown the need and usefulness of a combined approach to the design, analysis and evaluation of ICH antenna configurations. The work at the University of Wisconsin (UW) in particular has shown that much needed information on the vacuum operation of ICH antennas can be obtained by a modest experimental and computational effort. These model experiments at UW and SAIC simulations have shown dramatically the potential for positive impact upon the ICRF program. Results of the UW-SAIC joint ICRF antenna analysis effort have been presented at several international meetings and numerous meetings in the United States. The PPPL bay M antenna has been modeled using the ARGUS code. The results of this effort are shown in Appendix C. SAIC has recently begun a collaboration with the ICRF antenna design and analysis group at ORNL. At present there are two separate projects underway. The first is associated with the simulation of and determination of the effect of adding slots in the antenna septum and side walls. The second project concerns the modeling and simulation of the ORNL folded waveguide (FWG) concept.
Date: March 15, 1990
Partner: UNT Libraries Government Documents Department

Project: Collaborative Research Between Oklahoma State University and Fermilab

Description: Several scientific projects were completed in the area of Theoretical High Energy Physics (Elementary Particles and Fields). The results obtained were published in refereed international journals and presented in several national and international conferences by the project personnel. A brief summary of these four completed projects and the results obtained are given: (1) Collider Physics and Extra Dimensions; (2) Unification and Extra Dimensions; (3) Supersymmetry, Anomalous U(1) Symmetry and Lepton Flavor Violation; and (4) Neutrino Masses and Mixings.
Date: July 29, 2004
Partner: UNT Libraries Government Documents Department

Gene-Enzyme Relationships of Aromatic Amino Acid Biosynthesis in Higher Plants

Description: Inhibition studies of amino acids in Nicotiana silvestris suspension cells gave clues to the difficulties for obtaining mutants deficient in post prephenate pathway proteins of aromatic amino acid biosynthesis (prephenate aminotransferase, arogenate dehydrogenase and arogenate dehydratase). Such mutants, if successfully obtained, would allow gene-enzyme relationships of aromatic amino acid proteins to be studied. We found that amino acids were inhibitory toward plant cell growth, and thus were unable to rescue analog resistant mutants. Toxicity of all amino acids toward exponentially dividing Nicotiana silvestris suspension cultured cells was monitored by following growth rates. Except for L-glutamine, all 19 protein amino acids inhibited cell growth. Inhibition of growth progressed to cell deterioration. Electron microscopy showed that amino acids triggered a state of cell shrinkage that eventually degenerated to total cellular disorganization. L-glutamine was not only an effective agent for prevention of amino acid toxicity, but enhanced the final growth yield. L-glutamine also was able to completely reverse inhibition effects in cells that had been in the slowed exponential phase. Two types of inhibition occurred and we have proposed that any amino acid inhibition that can be completely antagonized by L-glutamine be called ''general amino acid inhibition''. ''Specific amino acid inhibition'' resulting from particular pathway imbalances caused by certain exogenous amino acids, can be recognized and studied in the presence of L-glutamine which can abolishes the complication effects of general amino acid inhibition.
Date: August 12, 2002
Partner: UNT Libraries Government Documents Department

PHOTOSYNTHESIS

Description: The Gordon Research Conference (GRC)on PHOTOSYNTHESIS was held at Roger Williams University, Bristol, RI. Emphasis was placed on current unpublished research and discussion of the future target areas in this field.
Date: June 21, 2002
Partner: UNT Libraries Government Documents Department

Water Science and Technology Board Annual Report 2001-2002

Description: This annual report marks the twentieth anniversary of the Water Science and Technology Board (WSTB) (1982-2002). The WSTB oversees studies of water issues. The principal products of studies are written reports. These reports cover a wide range of water resources issues of national concern. The following three recently issued reports illustrate the scope of the WSTB's studies: Envisioning the Agenda for Water Resources Research in the Twenty-first Century. The Missouri River Ecosystem: Exploring the Prospects for Recovery, and Assessing the TMDL Approach to Water Quality Management. The WSTB generally meets three times each year where discussions are held on ongoing projects, strategic planning, and developing new initiatives. The meetings also foster communication within the water resources community. The annual report includes a discussion on current studies, completed studies 2001-2002, and future plans, as well as a listing of published reports (1983-2002).
Date: October 1, 2002
Partner: UNT Libraries Government Documents Department

Mammalian DNA Repair. Final Report

Description: The Gordon Research Conference (GRC) on Mammalian DNA Repair was held at Harbortown Resort, Ventura Beach, CA. Emphasis was placed on current unpublished research and discussion of the future target areas in this field.
Date: January 24, 2003
Partner: UNT Libraries Government Documents Department

Chemical Physics Summer School

Description: The Gordon Research Conference (GRC) on Chemical Physics Summer School was held at Roger Williams University, Bristol, RI. Emphasis was placed on current unpublished research and discussion of the future target areas in this field.
Date: June 28, 2002
Partner: UNT Libraries Government Documents Department