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The Global Peace Operations Initiative: Background and Issues for Congress
This report describes in detail the Global Peace Operations Initiative (GPOI), the centerpiece of the Bush Administration's efforts to prepare foreign security forces to participate in international peacekeeping operations. This report lists the funding and allocations set aside for GPOI, as well as the function of GPOI and its future.
Date:
June 11, 2009
Creator:
Serafino, Nina M.
Object Type:
Report
System:
The UNT Digital Library
Preserving Our Collective Digital History
This presentation introduces the mission and the roles of the departments in the University of North Texas (UNT) Libraries and focuses on the infrastructure of the Digital Projects Unit.
Date:
March 11, 2009
Creator:
Phillips, Mark Edward
Object Type:
Presentation
System:
The UNT Digital Library
Federal Land Management: Observations on a Possible Move of the Forest Service into the Department of the Interior
A letter report issued by the Government Accountability Office with an abstract that begins "Growing ecological challenges ranging from wildland fires to climate change have revived interest in moving the Department of Agriculture's (USDA) Forest Service into the Department of the Interior (Interior). The Forest Service manages almost a quarter of the nation's lands but is the only major land management agency outside Interior. GAO was asked to report on the potential effects of moving the Forest Service into Interior and creating a new bureau equal to Interior's other bureaus, such as the Bureau of Land Management (BLM). GAO was also asked to identify factors that should be considered if such a move were legislated and management practices that could facilitate a move. GAO analyzed five historical proposals to reorganize federal land management agencies; interviewed USDA, Interior, and other officials and outside experts; and studied joint Forest Service- BLM programs to assess efforts to integrate the agencies' work."
Date:
February 11, 2009
Creator:
United States. Government Accountability Office.
Object Type:
Report
System:
The UNT Digital Library
Defense Acquisitions: Assessments Needed to Address V-22 Aircraft Operational and Cost Concerns to Define Future Investments
A letter report issued by the Government Accountability Office with an abstract that begins "Since the 1980s, the V-22, developed to transport combat troops, supplies, and equipment for the U.S. Marine Corps and to support other services' operations, has experienced several fatal crashes, demonstrated various deficiencies, and faced virtual cancellation--much of which it has overcome. Although until recently deployed in Iraq and regarded favorably, it has not performed the full range of missions anticipated, and how well it can do so is in question. In view of concerns about the V-22 program, you asked us to determine if the V-22 will perform as promised, and if it will, at what cost. GAO reviewed (1) current MV-22 operations in Iraq; (2) strengths and deficiencies in terms of the capabilities expected of the V-22; and (3) past, current, and future costs. GAO reviewed a range of program documents and data, interviewed program officials, operators and others; and observed MV-22 operations in Iraq and shipboard."
Date:
May 11, 2009
Creator:
United States. Government Accountability Office.
Object Type:
Report
System:
The UNT Digital Library
Public Housing: HUD's Oversight of Housing Agencies Should Focus More on Inappropriate Use of Program Funds
A letter report issued by the Government Accountability Office with an abstract that begins "The Department of Housing and Urban Development (HUD) provided over $6.7 billion in fiscal year 2008 to housing agencies to operate, modernize, and develop about 1.2 million public housing units. It is important that HUD exercise sufficient oversight of housing agencies to help ensure that public housing funds are being used as intended and properly managed. In this report, GAO examines HUD's oversight processes for detecting housing agencies at risk of inappropriate use and mismanagement of public housing funds. GAO analyzed HUD financial data on about 3,300 housing agencies, compared HUD's oversight policies with program and agency objectives, and interviewed agency officials."
Date:
June 11, 2009
Creator:
United States. Government Accountability Office.
Object Type:
Report
System:
The UNT Digital Library
National Institutes of Health: Completion of Comprehensive Risk Management Program Essential to Effective Oversight
A letter report issued by the Government Accountability Office with an abstract that begins "The National Institutes of Health (NIH), an agency of the Department of Health and Human Services (HHS), is the primary federal agency for supporting medical research. The Office of the Director (OD) is the central NIH office responsible for setting policy and overseeing NIH's 27 institutes and centers (IC). Allegations involving one institute raised questions about areas of oversight by the OD. In light of these questions, GAO examined (1) how NIH makes extramural research funding decisions and OD monitoring of this process, (2) the design of selected internal controls over NIH's travel and personnel appointment processes, and (3) the design of NIH's new risk management program and the program it is replacing. To address these objectives, GAO reviewed relevant NIH policies, procedures, and supporting documentation. GAO also selected 3 institutes that varied in size for in-depth reviews."
Date:
September 11, 2009
Creator:
United States. Government Accountability Office.
Object Type:
Report
System:
The UNT Digital Library
Business Systems Modernization: Internal Revenue Service's Fiscal Year 2009 Expenditure Plan
A letter report issued by the Government Accountability Office with an abstract that begins "The Internal Revenue Service's (IRS) Business Systems Modernization (BSM) program is a multi-billion-dollar, high-risk, highly complex effort that involves the development and delivery of a number of modernized systems that are intended to replace the agency's aging business and tax processing systems. As required, IRS submitted its fiscal year 2009 expenditure plan in August 2008 to the congressional appropriations committees, requesting $222 million from the BSM account. GAO's objectives in reviewing the expenditure plan were to (1) determine whether it satisfies the applicable legislative conditions, (2) determine IRS's progress in implementing prior expenditure plan review recommendations, and (3) provide additional observations about the plan and the BSM program. To accomplish the objectives, GAO analyzed the plan, reviewed related documentation, and interviewed IRS officials."
Date:
March 11, 2009
Creator:
United States. Government Accountability Office.
Object Type:
Report
System:
The UNT Digital Library
Clean Coal: DOE Should Prepare a Comprehensive Analysis of the Relative Costs, Benefits, and Risks of a Range of Options for FutureGen
Testimony issued by the Government Accountability Office with an abstract that begins "This testimony discusses our recent report on the Department of Energy's (DOE) decision to restructure the FutureGen program. The original FutureGen plant was to capture and store underground about 90 percent of its CO2 emissions. DOE's cost share was to be 74 percent, and industry partners agreed to fund the rest. Concerned about escalating costs, DOE announced in January 2008 that it had decided to restructure FutureGen. In October 2008, DOE received a small number of applications for the restructured FutureGen; however, some of these applications were for proposals outside the restructured FutureGen's scope. As we reported, DOE is currently assessing proposals received and stated it expected to announce a selection of projects by December 2008; however, as of the beginning of March 2009, it had made no decision. DOE requested supplemental information from restructured FutureGen applicants, which will be reviewed before any selection decision. As Congress may know, the recently enacted American Recovery and Reinvestment Act of 2009, known as the stimulus law, provides DOE an additional $3.4 billion for "Fossil Energy Research and Development." Such a substantial amount of funding could significantly impact DOE's decisions about …
Date:
March 11, 2009
Creator:
United States. Government Accountability Office.
Object Type:
Text
System:
The UNT Digital Library
National Airspace System: FAA Reauthorization Issues are Critical to System Transformation and Operations
Testimony issued by the Government Accountability Office with an abstract that begins "As requested, this statement discusses issues for the reauthorization of the Federal Aviation Administration (FAA). The aviation industry is in a period of economic turmoil and faces an uncertain future. At the same time, FAA is undertaking one of its most ambitious efforts ever to transform the nation's air traffic control system. The reauthorization of FAA provides an opportunity for Congress and FAA to focus on several key issues to improve the national airspace system. This statement is based on recent and ongoing work and on discussions with selected senior FAA officials and representatives of the aviation industry. This work was conducted in accordance with generally accepted government auditing standards. Those standards require that GAO plan and perform the audit to obtain sufficient, appropriate evidence to provide a reasonable basis for findings and conclusions based on the audit objectives. GAO believes that the evidence obtained provides a reasonable basis for the findings and conclusions based on the audit objectives."
Date:
February 11, 2009
Creator:
United States. Government Accountability Office.
Object Type:
Text
System:
The UNT Digital Library
Forest Service: Emerging Issues Highlight the Need to Address Persistent Management Challenges
Testimony issued by the Government Accountability Office with an abstract that begins "The Forest Service, within the Department of Agriculture, manages over 190 million acres of forest and grassland. The agency is responsible for managing its lands for various purposes--including recreation, grazing, timber harvesting, and others--while ensuring that such activities do not impair the lands' long-term productivity. Carrying out these often competing responsibilities has been made more difficult by the increasing cost of wildland fires and the budgetary constraints necessitated by our nation's long-term fiscal outlook. This testimony highlights some of the major management challenges the Forest Service faces in carrying out its land management responsibilities. It is based on numerous reports GAO has issued on a wide variety of the agency's activities."
Date:
March 11, 2009
Creator:
United States. Government Accountability Office.
Object Type:
Text
System:
The UNT Digital Library
Troubled Asset Relief Program: Status of Efforts to Address Transparency and Accountability Issues
Testimony issued by the Government Accountability Office with an abstract that begins "This testimony discusses our work on the Troubled Asset Relief Program (TARP), under which the Department of the Treasury (Treasury) has the authority to purchase and insure up to $700 billion in troubled assets held by financial institutions through its Office of Financial Stability (OFS). As Congress may know, Treasury was granted this authority in response to the financial crisis that has threatened the stability of the U.S. banking system and the solvency of numerous financial institutions. The Emergency Economic Stabilization Act (the act) that authorized TARP on October 3, 2008, requires GAO to report at least every 60 days on findings resulting from our oversight of the actions taken under TARP. This testimony is based primarily on our January 30, 2009 report, the second under the act's mandate, which covers the actions taken as part of TARP through January 23, 2009, and follows up on the nine recommendations we made in our December 2, 2008 report. This testomony also provides additional information on some recent developments related to TARP, including Treasury's new financial stability plan."
Date:
March 11, 2009
Creator:
United States. Government Accountability Office.
Object Type:
Text
System:
The UNT Digital Library
EPA Chemical Assessments: Process Reforms Offer the Potential to Address Key Problems
Testimony issued by the Government Accountability Office with an abstract that begins "The Environmental Protection Agency's (EPA) Integrated Risk Information System (IRIS) contains EPA's scientific position on the potential human health effects of exposure to more than 540 chemicals. Toxicity assessments in the IRIS database constitute the first two critical steps of the risk assessment process, which in turn provides the foundation for risk management decisions. Thus, IRIS is a critical component of EPA's capacity to support scientifically sound environmental decisions, policies, and regulations. GAO's 2008 report on the IRIS program identified significant concerns that, coupled with the importance of the program, caused GAO to add EPA's processes for assessing and controlling toxic chemicals as a high-risk area in its January 2009 biennial status report on governmentwide high-risk areas requiring increased attention by executive agencies and Congress. This testimony discusses (1) the findings from GAO's March 2008 report Chemical Assessments: Low Productivity and New Interagency Review Process Limit the Usefulness and Credibility of EPA's Integrated Risk Information System and related testimonies and (2) GAO's preliminary evaluation of the revised IRIS assessment process EPA issued on May 21, 2009. For this testimony, GAO supplemented its prior audit work with a preliminary …
Date:
June 11, 2009
Creator:
United States. Government Accountability Office.
Object Type:
Text
System:
The UNT Digital Library
Defense Management: Actions Needed to Overcome Long-standing Challenges with Weapon Systems Acquisition and Service Contract Management
Testimony issued by the Government Accountability Office with an abstract that begins "Today's testimony addresses the challenges DOD faces to improve the efficiency and effectiveness of its weapon systems acquisition and contract management. GAO has designated both areas as high risk areas since the early 1990s. DOD's major weapon systems programs continue to take longer to develop, cost more, and deliver fewer quantities and capabilities than originally planned. DOD also continues to face long-standing challenges managing service contracts and contractors. For example, the oversight of service contracts has been recognized as a material weakness in the Army. The current fiscal environment combined with the current operational demands elevates the need to improve weapon systems acquisition and contract management. DOD has taken steps in response to recommendations GAO has made over the past decade. Taken collectively, these actions reflect the commitment of DOD senior leadership. However, to fully address these challenges the department needs to (1) translate policy into practice, (2) ensure steps undertaken result in intended outcomes, and (3) conduct a fundamental reexamination of its reliance on contractors. In preparing this testimony, GAO drew from issued reports, containing statements of scope and methodology used, and testimonies."
Date:
February 11, 2009
Creator:
United States. Government Accountability Office.
Object Type:
Text
System:
The UNT Digital Library
Technical Risk Rating of DOE Environmental Projects - 9153
The U.S. Department of Energy's Office of Environmental Management (DOE-EM) was established to achieve the safe and compliant disposition of legacy wastes and facilities from defense nuclear applications. The scope of work is diverse, with projects ranging from single acquisitions to collections of projects and operations that span several decades and costs from hundreds of millions to billions US$. The need to be able to manage and understand the technical risks from the project to senior management level has been recognized as an enabler to successfully completing the mission. In 2008, DOE-EM developed the Technical Risk Rating as a new method to assist in managing technical risk based on specific criteria. The Technical Risk Rating, and the criteria used to determine the rating, provides a mechanism to foster open, meaningful communication between the Federal Project Directors and DOE-EM management concerning project technical risks. Four indicators (technical maturity, risk urgency, handling difficulty and resolution path) are used to focus attention on the issues and key aspects related to the risks. Pressing risk issues are brought to the forefront, keeping DOE-EM management informed and engaged such that they fully understand risk impact. Use of the Technical Risk Rating and criteria during reviews …
Date:
February 11, 2009
Creator:
Cercy, Michael; Fayfich, Ronald & Schneider, Steven
Object Type:
Article
System:
The UNT Digital Library
ON THE IMPACT OF SUPER RESOLUTION WSR-88D DOPPLER RADAR DATA ASSIMILATION ON HIGH RESOLUTION NUMERICAL MODEL FORECASTS
Assimilation of radar velocity and precipitation fields into high-resolution model simulations can improve precipitation forecasts with decreased 'spin-up' time and improve short-term simulation of boundary layer winds (Benjamin, 2004 & 2007; Xiao, 2008) which is critical to improving plume transport forecasts. Accurate description of wind and turbulence fields is essential to useful atmospheric transport and dispersion results, and any improvement in the accuracy of these fields will make consequence assessment more valuable during both routine operation as well as potential emergency situations. During 2008, the United States National Weather Service (NWS) radars implemented a significant upgrade which increased the real-time level II data resolution to 8 times their previous 'legacy' resolution, from 1 km range gate and 1.0 degree azimuthal resolution to 'super resolution' 250 m range gate and 0.5 degree azimuthal resolution (Fig 1). These radar observations provide reflectivity, velocity and returned power spectra measurements at a range of up to 300 km (460 km for reflectivity) at a frequency of 4-5 minutes and yield up to 13.5 million point observations per level in super-resolution mode. The migration of National Weather Service (NWS) WSR-88D radars to super resolution is expected to improve warning lead times by detecting small scale …
Date:
January 11, 2009
Creator:
Chiswell, S
Object Type:
Article
System:
The UNT Digital Library
Ionic Liquids for Utilization of Waste Heat from Distributed Power Generation Systems
The objective of this research project was the development of ionic liquids to capture and utilize waste heat from distributed power generation systems. Ionic Liquids (ILs) are organic salts that are liquid at room temperature and they have the potential to make fundamental and far-reaching changes in the way we use energy. In particular, the focus of this project was fundamental research on the potential use of IL/CO2 mixtures in absorption-refrigeration systems. Such systems can provide cooling by utilizing waste heat from various sources, including distributed power generation. The basic objectives of the research were to design and synthesize ILs appropriate for the task, to measure and model thermophysical properties and phase behavior of ILs and IL/CO2 mixtures, and to model the performance of IL/CO2 absorption-refrigeration systems.
Date:
January 11, 2009
Creator:
Brennecke, Joan F.; Sen, Mihir; Maginn, Edward J.; Paolucci, Samuel; Stadtherr, Mark A.; Disser, Peter T. et al.
Object Type:
Report
System:
The UNT Digital Library
Thermal Cycling on Fatigue Failure of the Plutonium Vitrification Melter
One method for disposition of excess plutonium is vitrification into cylindrical wasteforms. Due to the hazards of working with plutonium, the vitrification process must be carried out remotely in a shielded environment. Thus, the equipment must be easily maintained. With their simple design, induction melters satisfy this criterion, making them ideal candidates for plutonium vitrification. However, due to repeated heating and cooling cycles and differences in coefficients of thermal expansion of contacting materials fatigue failure of the induction melter is of concern. Due to the cost of the melter, the number of cycles to failure is critical. This paper presents a method for determining the cycles to failure for an induction melter by using the results from thermal and structural analyses as input to a fatigue failure model.
Date:
February 11, 2009
Creator:
Jordan, Jeffrey & Gorczyca, Jennifer
Object Type:
Article
System:
The UNT Digital Library
Enhanced Chemical Cleaning: A New Process for Chemically Cleaning Savannah River Waste Tanks
At the Savannah River Site (SRS) there are 49 High Level Waste (HLW) tanks that eventually must be emptied, cleaned, and closed. The current method of chemically cleaning SRS HLW tanks, commonly referred to as Bulk Oxalic Acid Cleaning (BOAC), requires about a half million liters (130,000 gallons) of 8 weight percent (wt%) oxalic acid to clean a single tank. During the cleaning, the oxalic acid acts as the solvent to digest sludge solids and insoluble salt solids, such that they can be suspended and pumped out of the tank. Because of the volume and concentration of acid used, a significant quantity of oxalate is added to the HLW process. This added oxalate significantly impacts downstream processing. In addition to the oxalate, the volume of liquid added competes for the limited available tank space. A search, therefore, was initiated for a new cleaning process. Using TRIZ (Teoriya Resheniya Izobretatelskikh Zadatch or roughly translated as the Theory of Inventive Problem Solving), Chemical Oxidation Reduction Decontamination with Ultraviolet Light (CORD-UV{reg_sign}), a mature technology used in the commercial nuclear power industry was identified as an alternate technology. Similar to BOAC, CORD-UV{reg_sign} also uses oxalic acid as the solvent to dissolve the metal (hydr)oxide …
Date:
February 11, 2009
Creator:
Ketusky, Edward; Spires, Renee & Davis, Neil
Object Type:
Article
System:
The UNT Digital Library
Sludge Batch 5 Slurry Fed Melt Rate Furnace Test with Frits 418 and 550
Based on Melt Rate Furnace (MRF) testing for the Sludge Batch 5 (SB5) projected composition and assessments of the potential frits with reasonable operating windows, the Savannah River National Laboratory (SRNL) recommended Slurry Fed Melt Rate Furnace (SMRF) testing with Frits 418 and 550. DWPF is currently using Frit 418 with SB5 based on SRNL's recommendation due to its ability to accommodate significant sodium variation in the sludge composition. However, experience with high boron containing frits in DWPF indicated a potential advantage for Frit 550 might exist. Therefore, SRNL performed SMRF testing to assess Frit 550's potential advantages. The results of SMRF testing with SB5 simulant indicate that there is no appreciable difference in melt rate between Frit 418 and Frit 550 at a targeted 34 weight % waste loading. Both batches exhibited comparable behavior when delivered through the feed tube by the peristaltic pump. Limited observation of the cold cap during both runs showed no indication of major cold cap mounding. MRF testing, performed after the SMRF runs due to time constraints, with the same two Slurry Mix Evaporator (SME) dried products led to the same conclusion. Although visual observations of the cross-sectioned MRF beakers indicated differences in the …
Date:
February 11, 2009
Creator:
Miller, Donald & Pickenheim, Bradley
Object Type:
Report
System:
The UNT Digital Library
Tank 26 Evaporator Feed Pump Transfer Analysis
The transfer of liquid salt solution from Tank 26 to an evaporator is to be accomplished by activating the evaporator feed pump, located approximately 72 inches above the sludge layer, while simultaneously turning on the downcomer. Previously, activation of the evaporator feed pump was an isolated event without any other components running at the same time. An analysis of the dissolved solution transfer has been performed using computational fluid dynamics methods to determine the amount of entrained sludge solids pumped out of the tank to the evaporator with the downcomer turned on. The analysis results showed that, for the maximum and minimum supernate levels in Tank 26 (252.5 and 72 inches above the sludge layer, respectively), the evaporator feed pump will entrain between 0.03 and 0.1 wt% sludge undissolved solids weight fraction into the eductor, respectively, and therefore are an order of magnitude less than the 1.0 wt% undissolved solids loading criteria to feed the evaporator. Lower tank liquid levels, with respect to the sludge layer, result in higher amounts of sludge entrainment due to the increased velocity of the plunging jets from the downcomer and evaporator feed pump bypass as well as decreased dissipation depth. Revision 1 clarifies the …
Date:
February 11, 2009
Creator:
Tamburello, David; Dimenna, Richard & Lee, Si
Object Type:
Report
System:
The UNT Digital Library
Salt Processing Through Ion Exchange at the Savannah River Site Selection of Exchange Media and Column Configuration - 9198
The Department of Energy (DOE) has developed, modeled, and tested several different ion exchange media and column designs for cesium removal. One elutable resin and one non-elutable resin were considered for this salt processing application. Deployment of non-elutable Crystalline Silicotitanate and elutable Resorcinol Formaldehyde in several different column configurations were assessed in a formal Systems Engineering Evaluation (SEE). Salt solutions were selected that would allow a grouping of non-compliant tanks to be closed. Tests were run with the elutable resin to determine compatibility with the resin configuration required for an in-tank ion exchange system. Models were run to estimate the ion exchange cycles required with the two resins in several column configurations. Material balance calculations were performed to estimate the impact on the High Level Waste (HLW) system at the Savannah River Site (SRS). Conceptual process diagrams were used to support the hazard analysis. Data from the hazard analysis was used to determine the relative impact on safety. This report will discuss the technical inputs, SEE methods, results and path forward to complete the technical maturation of ion exchange.
Date:
February 11, 2009
Creator:
Spires, Renee; Punch, Timothy & McCabe, Daniel
Object Type:
Article
System:
The UNT Digital Library
NERI FINAL TECHNICAL REPORT, DE-FC07-O5ID14647, OPTIMIZATION OF OXIDE COMPOUNDS FOR ADVANCED INERT MATRIX MATERIALS
In order to reduce the current excesses of plutonium (both weapon grade and reactor grade) and other transuranium elements, a concept of inert matrix fuel (IMF) has been proposed for an uranium free transmutation of fissile actinides which excludes continuous uranium-plutonium conversion in thermal reactors and advanced systems. Magnesium oxide (MgO) is a promising candidate for inert matrix (IM) materials due to its high melting point (2827 C), high thermal conductivity (13 W/K {center_dot} m at 1000 C), good neutronic properties, and irradiation stability However, MgO reacts with water and hydrates easily, which prevents it from being used in light water reactors (LWRs) as an IM. To improve the hydration resistance of MgO-based inert matrix materials, Medvedev and coworkers have recently investigated the introduction of a secondary phase that acts as a hydration barrier. An MgO-ZrO{sub 2} composite was specifically studied and the results showed that the composite exhibited improved hydration resistance than pure MgO. However, ZrO{sub 2} is insoluble in most acids except HF, which is undesirable for fuel reprocessing. Moreover, the thermal conductivity of ZrO{sub 2} is low and typically less than 3 W {center_dot} m{sup -1} {center_dot} K{sup -1} at 1000 C. In search for an alternative …
Date:
January 11, 2009
Creator:
PI: JUAN C. NINO, ASSOCIATE PROFESSOR
Object Type:
Report
System:
The UNT Digital Library
Tracking the Sun: The Installed Cost of Photovoltaics in the U.S. from 1998-2007
As installations of grid-connected solar photovoltaic (PV) systems have grown, so too has the desire to track the installed cost of these systems over time, by system characteristics, by system location, and by component. This report helps to fill this need by summarizing trends in the installed cost of grid-connected PV systems in the United States from 1998 through 2007. The report is based on an analysis of installed cost data from nearly 37,000 residential and non-residential PV systems, totaling 363 MW of capacity, and representing 76percent of all grid-connected PV capacity installed in the U.S. through 2007.
Date:
February 11, 2009
Creator:
Wiser, Ryan; Barbose, Galen & Peterman, Carla
Object Type:
Report
System:
The UNT Digital Library
Peroxotitanates for Biodelivery of Metals
Metal-based drugs are largely undeveloped in pharmacology. One limiting factor is the systemic toxicity of metal-based compounds. A solid-phase, sequestratable delivery agent for local delivery of metals could reduce systemic toxicity, facilitating new drug development in this nascent area. Amorphous peroxotitanates (APT) are ion exchange materials with high affinity for several heavy metal ions, and have been proposed to deliver or sequester metal ions in biological contexts. In the current study, we tested a hypothesis that APT are able to deliver metals or metal compounds to cells. We exposed fibroblasts (L929) or monocytes (THP1) to metal-APT materials for 72 h in vitro, then measured cellular mitochondrial activity (SDH-MTT method) to assess the biological impact of the metal-APT materials vs. metals or APT alone. APT alone did not significantly affect cellular mitochondrial activity, but all metal-APT materials suppressed the mitochondrial activity of fibroblasts (by 30-65% of controls). The concentration of metal-APT materials required to suppress cellular mitochondrial activity was below that required for metals alone, suggesting that simple extracellular release of the metals from the metal-APT materials was not the primary mechanism of mitochondrial suppression. In contrast to fibroblasts, no metal-APT material had a measurable effect on THP1 monocyte mitochondrial activity, …
Date:
February 11, 2009
Creator:
Hobbs, David & Elvington, M.
Object Type:
Article
System:
The UNT Digital Library