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Idle Iron in the Gulf of Mexico

Description: Offshore structures are required to be removed within a year after production ceases and recently the Minerals Management Service has asked for removal of structures no longer "economically viable." This paper seeks to identify the amount of idle iron that exists in the Gulf of Mexico as well as describe the geographic distribution and ownership patterns.
Date: May 2007
Creator: Kaiser, Mark J. & Pulsipher, Allan G.
Partner: UNT Libraries Government Documents Department

Sensor and actuator considerations for precision, small machines: a review

Description: This article reviews some design considerations for the scaling down in size of instruments and machines with a primary aim to identify technologies that may provide more optimal performance solutions than those, often established, technologies used at macroscopic, or conventional, scales. Dimensional metrology within emerging applications will be considered for meso- through micro-down to nanometer level systems with particular emphasis on systems for which precision is directly related to function. In this paper, attention is limited to some of the more fundamental issues associated with scaling. For example, actuator work or power densities or the effect of noise on the sensor signals can be readily evaluated and provide some guidance in the selection for any given size of device. However, with reductions in scale these parameters and/or phenomena that limit performance may change. Within this review, the authors have tried to assess these complex inter-relationships between performance and scale, again from a fundamental perspective. In practice, it is likely that the nuances of implementation and integration of sensor, actuator and/or mechanism designs will determine functionality and commercial viability of any particular system development.
Date: April 4, 2005
Creator: Smith, S T & Seugling, R M
Partner: UNT Libraries Government Documents Department

CO2 Huff-n-Puff Process in a Light Oil Shallow Shelf Carbonate Reservoir

Description: The application cyclic CO2, often referred to as the CO2 Huff-n-Puff process, may find its niche in the maturing waterfloods of the Permian Basin. Coupling the CO2 Huff-n-Puff process to miscible flooding applications could provide the needed revenue to sufficiently mitigate near-term negative cash flow concerns in capital-intensive miscible projects. Texaco Exploration and Production Inc. and the US Department of Energy have teamed up in a attempt to develop the CO2 Huff-n-Puff process in the Grayburg and San Andres formations which are light oil, shallow shelf carbonate reservoirs that exist throughout the Permian Basin. This cost-shared effort is intended to demonstrate the viability of this underutilized technology in a specific class of domestic reservoir.
Date: February 24, 1999
Creator: Boomer, R. J.; Cole, R.; Kovar, M.; Prieditis, J.; Vogt, J. & Wehner, S.
Partner: UNT Libraries Government Documents Department

Population Viability Analysis of Riverine Fishes

Description: Many utilities face conflkts between two goals: cost-efficient hydropower generation and protecting riverine fishes. Research to develop ecological simulation tools that can evaluate alternative mitigation strategies in terms of their benefits to fish populations is vital to informed decision-making. In this paper, we describe our approach to population viability analysis of riverine fishes in general and Snake River white sturgeon in particular. We are finding that the individual-based modeling approach used in previous in-stream flow applications is well suited to addressing questions about the viability of species of concern for several reasons. Chief among these are: (1) the abiIity to represent the effects of individual variation in life history characteristics on predicted population viabili~, (2) the flexibili~ needed to quanti~ the ecological benefits of alternative flow management options by representing spatial and temporal variation in flow and temperaturty and (3) the flexibility needed to quantifi the ecological benefits of non-flow related manipulations (i.e., passage, screening and hatchery supplementation).
Date: April 12, 1999
Creator: Bates, P.; Chandler, J.; Jager, H.I.; Lepla, K. & Van Winkle, W.
Partner: UNT Libraries Government Documents Department

Spatial Uncertainty Analysis of Ecological Models

Description: The authors evaluated the sensitivity of a habitat model and a source-sink population model to spatial uncertainty in landscapes with different statistical properties and for hypothetical species with different habitat requirements. Sequential indicator simulation generated alternative landscapes from a source map. Their results showed that spatial uncertainty was highest for landscapes in which suitable habitat was rare and spatially uncorrelated. Although, they were able to exert some control over the degree of spatial uncertainty by varying the sampling density drawn from the source map, intrinsic spatial properties (i.e., average frequency and degree of spatial autocorrelation) played a dominant role in determining variation among realized maps. To evaluate the ecological significance of landscape variation, they compared the variation in predictions from a simple habitat model to variation among landscapes for three species types. Spatial uncertainty in predictions of the amount of source habitat depended on both the spatial life history characteristics of the species and the statistical attributes of the synthetic landscapes. Species differences were greatest when the landscape contained a high proportion of suitable habitat. The predicted amount of source habitat was greater for edge-dependent (interior) species in landscapes with spatially uncorrelated(correlated) suitable habitat. A source-sink model demonstrated that, although variation among landscapes resulted in relatively little variation in overall population growth rate, this spatial uncertainty was sufficient in some situations, to produce qualitatively different predictions about population viability (i.e., population decline vs. increase).
Date: September 2, 2000
Creator: Jager, H.I.; Ashwood, T.L.; Jackson, B.L. & King, A.W.
Partner: UNT Libraries Government Documents Department

Advanced Reservoir Characterization in the Antelope Shale to Establish the Viability of CO2 Enhanced Oil Recovery in California's Monterey Formation Siliceous Shales, Class III

Description: The primary objective of this project was to conduct advanced reservoir characterization and modeling studies in the Antelope Shale of the Bureau Vista Hills Field. Work was subdivided into two phases or budget periods. The first phase of the project focused on a variety of advanced reservoir characterization techniques to determine the production characteristics of the Antelope Shale reservoir. Reservoir models based on the results of the characterization work would then be used to evaluate how the reservoir would respond to enhanced oil recovery (EOR) processes such as of CO2 flooding. The second phase of the project would be to implement and evaluate a CO2 in the Buena Vista Hills Field. A successful project would demonstrate the economic viability and widespread applicability of CO2 flooding in siliceous shale reservoirs of the San Joaquin Valley.
Date: April 24, 2000
Creator: Perri, Pasquale R.; Cooney, John; Fong, Bill; Julander, Dale; Marasigan, Aleks; Morea, Mike et al.
Partner: UNT Libraries Government Documents Department

The Financial Viability of Conrail

Description: A review prepared by the the Office of Technology Assessment (OTA) based on the Final System Plan of the Consolidated Rail Corporation (ConRail) of 1974. It "examines "the critical assumptions affecting ConRail's financial viability using background data developed by USRA, the views of the key parties and independent analysis" (p.1).
Date: September 1975
Creator: United States. Congress. Office of Technology Assessment.
Partner: UNT Libraries Government Documents Department

Demonstration and Field Test of airjacket technology

Description: There are approximately 600,000 paint spray workers in the United States applying paints and coatings with some type of sprayer. Approximately 5% of these spray workers are in the South Coast Air Quality Management District (SCAQMD). These spray workers apply paints or other coatings to products such as bridges, houses, automobiles, wood and metal furniture, and other consumer and industrial products. The materials being sprayed include exterior and interior paints, lacquers, primers, shellacs, stains and varnishes. Our experimental findings indicate that the Airjacket does not significantly reduce the exposure of spray workers to paint fumes during HVLP spraying. The difference between ideal and actual spray paint procedures influence the mechanisms driving spray workers exposures to paint fumes and influence the viability of the Airjacket technology. In the ideal procedure, for which the Airjacket was conceived, the spray worker's exposure to paint fumes is due largely to the formation of a recirculating eddy between the spray worker and the object painted. The Airjacket ejects air to diminish and ventilate this eddy. In actual practice, exposures may result largely from directing paint upstream and from the bounce-back of the air/paint jet of the object being painted. The Airjacket, would not be expected to dramatically reduce exposures to paint fumes when the paint is not directed downstream or when the bounce-back of paint on the object creates a cloud of paint aerosols around the spray worker.
Date: June 1, 1998
Creator: Faulkner, D.; Fisk, W.J.; Gadgil, A.J. & Sullivan, D.P.
Partner: UNT Libraries Government Documents Department

The Impact of Retail Rate Structures on the Economics ofCommercial Photovoltaic Systems in California

Description: To achieve a sizable and self-sustaining market for grid-connected, customer-sited photovoltaic (PV) systems, solar will likely need to be competitive with retail electricity rates. In this report, we examine the impact of retail rate design on the economic value of commercial PV systems in California. Using 15-minute interval building load and PV production data from 24 actual commercial PV installations, we compare the value of the bill savings across 20 commercial customer retail rates currently offered in the state. We find that the specifics of the rate structure, combined with the characteristics of the customer's underlying load and the size of the PV system, can have a substantial impact on the customer-economics of commercial PV systems. Key conclusions for policymakers that emerge from our analysis are as follows: {sm_bullet} Rate design is fundamental to the economics of commercial PV. The rate-reduction value of PV for our sample of commercial customers, considering all available retail tariffs, ranges from $0.05/kWh to $0.24/kWh, reflecting differences in rate structures, the revenue requirements of the various utilities, the size of the PV system relative to building load, and customer load shapes. For the average customer in our sample, differences in rate structure, alone, alter the value of PV by 25% to 75%, depending on the size of the PV system relative to building load. {sm_bullet} TOU-based energy-focused rates can provide substantial value to many PV customers. Retail rates that wrap all or most utility cost recovery needs into time-of-use (TOU)-based volumetric energy rates, and which exclude or limit demand-based charges, provide the most value to PV systems across a wide variety of circumstances. Expanding the availability of such rates will increase the value of many commercial PV systems. {sm_bullet} Offering commercial customers a variety of rate options would be of value to PV. Despite the ...
Date: July 3, 2007
Creator: Wiser, Ryan; Mills, Andrew; Barbose, Galen & Golove, William
Partner: UNT Libraries Government Documents Department

PXIE: Project X Injector Experiment

Description: A multi-MW proton facility, Project X, has been proposed and is currently under development at Fermilab. We are planning a program of research and development aimed at integrated systems testing of critical components comprising the front end of the Project X. This program is being undertaken as a key component of the larger Project X R&D program. The successful completion of this program will validate the concept for the Project X front end, thereby minimizing a primary technical risk element within Project X. Integrated systems testing, known as the Project X Injector Experiment (PXIE), will be accomplished with a new test facility under construction at Fermilab and will be completed over the period FY12-16. PXIE will include an H{sup -} ion source, a CW 2.1-MeV RFQ and two superconductive RF (SRF) cryomodules providing up to 25 MeV energy gain at an average beam current of 1 mA (upgradable to 2 mA). Successful systems testing will also demonstrate the viability of novel front end technologies that are expected find applications beyond Project X.
Date: May 1, 2012
Creator: Ostroumov, P.N.; /Argonne; Holmes, S.D.; Kephart, R.D.; Kerby, J.S.; Lebedev, V.A. et al.
Partner: UNT Libraries Government Documents Department

Next Steps to Implement Renewable Energy Project on the Makah Indian Naiton for the Pacific North West Region

Description: The two year feasibility project was conducted to determine if the Makah reservation wind resource is viable for commercial generation and to investigate the viability and implementaiton of a tribal utility company capable of conducting energy business on the reservation.
Date: December 30, 2005
Creator: Martin Wilde, Coyote Energy, Inc.
Partner: UNT Libraries Government Documents Department

Building America

Description: IBACOS researched the constructability and viability issues of using high performance windows as one component of a larger approach to building houses that achieve the Building America 70% energy savings target.
Date: December 31, 2010
Creator: Oberg, Brad
Partner: UNT Libraries Government Documents Department

Autofluorescence dynamics during reperfusion following long-term renal ischemia in a rat model

Description: Optical properties of near-surface kidney tissue were monitored in order to assess response during reperfusion to long (20 minutes) versus prolonged (150 minutes) ischemia in an in vivo rat model. Specifically, autofluorescence images of the exposed surfaces of both the normal and the ischemic kidneys were acquired during both injury and reperfusion alternately under 355 nm and 266 nm excitations. The temporal profile of the emission of the injured kidney during the reperfusion phase under 355 nm excitation was normalized to that under 266 nm as a means to account for changes in tissue optical properties independent of ischemia as well as changes in the illumination/collection geometrical parameters in future clinical implementation of this technique using a hand-held probe. The scattered excitation light signal was also evaluated as a reference signal and found to be inadequate. Characteristic time constants were extracted using fit to a relaxation model and found to have larger mean values following 150 minutes of injury. The mean values were then compared with the outcome of a chronic survival study where the control kidney had been removed. Rat kidneys exhibiting longer time constants were much more likely to fail. This may lead to a method to assess kidney viability and predict its ability to recover in the initial period following transplantation or resuscitation.
Date: February 8, 2008
Creator: Raman, R N; Pivetti, C D; Matthews, D L; Troppmann, C & Demos, S G
Partner: UNT Libraries Government Documents Department

Industrial Consortium for the Utilization of the Geopressured-Geothermal Resource. Volume 1

Description: The Geopressured-Geothermal Program, now in its fifteenth year, is entering the transition period to commercial use. The industry cost-shared proposals to the consortium, represented in the presentations included in these proceedings, attest to the interest developing in the industrial community in utilizing the geopressured-geothermal resource. Sixty-five participants attended these sessions, two-thirds of whom represented industry. The areas represented by cost-shared proposals include (1) thermal enhanced oil recovery, (2) direct process use of thermal energy, e.g., aquaculture and agriculture, (3) conversion of thermal energy to electricity, (4) environment related technologies, e.g., use of supercritical processes, and (5) operational proposals, e.g., a field manual for scale inhibitors. It is hoped that from this array of potential use projects, some will persist and be successful in proving the viability of using the geopressured-geothermal resource. Such industrial use of an alternative and relatively clean energy resource will benefit our nation and its people.
Date: March 1, 1990
Creator: Negus-deWys, J. (ed.)
Partner: UNT Libraries Government Documents Department

Industrial Consortium for the Utilization of the Geopressured-Geothermal Resource. Volume 2

Description: The Geopressured-Geothermal Program, now in its fifteenth year, is entering the transition period to commercial use. The industry cost-shared proposals to the consortium, represented in the presentations included in these proceedings, attest to the interest developing in the industrial community in utilizing the geopressured-geothermal resource. Sixty-five participants attended these sessions, two-thirds of whom represented industry. The areas represented by cost-shared proposals include (1) thermal enhanced oil recovery, (2) direct process use of thermal energy, e.g., aquaculture and agriculture, (3) conversion of thermal energy to electricity, (4) environment related technologies, e.g., use of supercritical processes, and (5) operational proposals, e.g., a field manual for scale inhibitors. It is hoped that from this array of potential use projects, some will persist and be successful in proving the viability of using the geopressured-geothermal resource. Such industrial use of an alternative and relatively clean energy resource will benefit our nation and its people.
Date: March 1, 1990
Creator: Negus-deWys, J. (ed.)
Partner: UNT Libraries Government Documents Department

An Innovative High-Temperature High-Pressure Measurement While Drilling (MWD) Tool

Description: Measurement while drilling (MWD) tools specified to 150 C (302 F) that provide wellbore surveys, real-time inclination, and natural gamma ray detection are a commodity item in the oilfield services industry. MWD tools specified to 175 C (347 F) that routinely demonstrate highly reliable operation are available from only a few service companies. Commercial MWD tools that reliably operate to 200 C (392 F) for extended periods of time and offer features like real-time gamma ray, retrievability, and reseatability are nonexistent. Need for these higher temperature tools will increase as wells become hotter in the search for new oil and gas resources. The goal of this project was to design a retrievable and reseatable high-pressure/high-temperature MWD tool with real-time continuous inclination, vibration detection, annular pressure, and gamma ray detection. This report describes the development of such a tool from concept, through feasibility, and into field testing and preliminary development planning. It describes the challenges encountered in the design of the tool, along with testing results and decisions about the commercial viability of the tool in the configuration in which it was developed. The decision was made not to commercialize the tool developed under this project because of a combination of battery technology problems and modulation power consumption at the required depths.
Date: June 1, 2007
Creator: Boling, Brian
Partner: UNT Libraries Government Documents Department

Development of a Low-Cost Rotary Steerable Drilling System

Description: The project had the goal to develop and commercialize a low-cost rotary steerable system (LCRSS) capable of operating downhole at conventional pressures and temperatures to reduce operating costs by a minimum of 50% and lost-in-hole charges by at least 50% over the currently offered systems. The LCRSS system developed under this project does reduce operating costs by 55% and lost-in-hole charges by at least 50%. The developed product is not commercializable in its current form. The overall objective was to develop and commercialize a low cost rotary steerable system (LCRSS) capable of operating downhole at conventional pressures and temperatures (20,000 psi/150 C) while reducing the operating costs by 50% and the lost-in-hole charges by 50% over the currently available systems. The proposed reduction in costs were to be realized through the significant reduction in tool complexity, a corresponding increase in tool reliability as expressed in the mean-time between failure (MTBF), and a reduction in the time and costs required to service tools after each field operation. Ultimately, the LCRSS system was to be capable of drilling 7 7/8 in. to 9 5/8 in. borehole diameters. The project was divided into three Phases, of which Phases I & II were previously completed and reported on, and are part of the case file. Therefore, the previously reported information is not repeated herein. Phase III included the fabrication of two field ready prototypes that were to be subjected to a series of drilling tests at GTI Catoosa, DOE RMOTC, and at customer partnering wells, if possible, as appropriate in the timing of the field test objectives to fully exercise all elements of the LCRSS. These tests were conducted in an iterative process based on a performance/reliability improvement cycle with the goal of demonstrating the system met all aspects required for commercial viability. These ...
Date: January 31, 2012
Creator: Nazarian, Roney
Partner: UNT Libraries Government Documents Department

Effect of Heat and Electricity Storage and Reliability on Microgrid Viability: A Study of Commercial Buildings in California and New York States

Description: Berkeley Lab has for several years been developing methods for selection of optimal microgrid systems, especially for commercial building applications, and applying these methods in the Distributed Energy Resources Customer Adoption Model (DER-CAM). This project began with 3 major goals: (1) to conduct detailed analysis to find the optimal equipment combination for microgrids at a few promising commercial building hosts in the two favorable markets of California and New York, (2) to extend the analysis capability of DER-CAM to include both heat and electricity storage, and (3) to make an initial effort towards adding consideration of power quality and reliability (PQR) to the capabilities of DER-CAM. All of these objectives have been pursued via analysis of the attractiveness of a Consortium for Electric Reliability Technology Solutions (CERTS) Microgrid consisting of multiple nameplate 100 kW Tecogen Premium Power Modules (CM-100). This unit consists of an asynchronous inverter-based variable speed internal combustion engine genset with combined heat and power (CHP) and power surge capability. The essence of CERTS Microgrid technology is that smarts added to the on-board power electronics of any microgrid device enables stable and safe islanded operation without the need for complex fast supervisory controls. This approach allows plug and play development of a microgrid that can potentially provide high PQR with a minimum of specialized site-specific engineering. A notable feature of the CM-100 is its time-limited surge rating of 125 kW, and DER-CAM capability to model this feature was also a necessary model enhancement.
Date: March 10, 2009
Creator: Stadler, Michael; Marnay, Chris; Siddiqui, Afzal; Lai, Judy; Coffey, Brian & Aki, Hirohisa
Partner: UNT Libraries Government Documents Department

Estimating Well Costs for Enhanced Geothermal System Applications

Description: The objective of the work reported was to investigate the costs of drilling and completing wells and to relate those costs to the economic viability of enhanced geothermal systems (EGS). This is part of a larger parametric study of major cost components in an EGS. The possibility of improving the economics of EGS can be determined by analyzing the major cost components of the system, which include well drilling and completion. Determining what costs in developing an EGS are most sensitive will determine the areas of research to reduce those costs. The results of the well cost analysis will help determine the cost of a well for EGS development.
Date: August 1, 2005
Creator: Bloomfield, K. K. & Laney, P. T.
Partner: UNT Libraries Government Documents Department

Effects of Chromium(VI) and Chromium(III) on Desulfovibrio vulgaris Cells

Description: Desulfovibrio vulgaris ATCC 29579 is a well studied sulfate reducer that has known capabilities of reducing heavy metals and radionuclides, like chromium and uranium. Cultures grown in a defined medium (i.e. LS4D) had a lag period of approximately 40 h when exposed to 50 ╬╝Mof Cr(VI). Substrate analysis revealed that although chromium is reduced within the first 5 h, growth does not resume for another 35 h. During this time, small amounts of lactate are still utilized but the reduction of sulfate does not occur. Sulfate reduction occurs concurrently with the accumulation of acetate approximately 40 h after inoculation, when growth resumes. Similar amounts of hydrogen are produced during this time compared to hydrogen production by cells not exposed to Cr(VI); therefore an accumulation of hydrogen cannot account for the utilization of lactate. There is a significant decrease in the carbohydrate to protein ratio at approximately 25 h, and this result indicated that lactate is not converted to glycogen. Most probable number analysis indicated that cell viability decreased steadily after inoculation and reached approximately 6 x 104 cells/ml 20 h post-chromium exposure. Regeneration of reducing conditions during chromium exposure does not induce growth and in fact may make the growth conditions even more unfavorable. This result suggested that an increase in Eh was not solely responsible for the decline in viability. Cell pellets collected 10 h after chromium-exposure were unable to resume growth when suspended into fresh medium. Supernatants from these pellets were able to support cell growth upon re- inoculation. D. vulgaris cells treated with a non-dose dependent addition of ascorbate at the same time of Cr(VI) addition did not enter a lag period. Ascorbate added 3 h post-Cr(VI) exposure did not prevent the growth lag. These results indicated that Desulfovibrio utilized lactate to reduce Cr(VI) without the reduction ...
Date: April 19, 2007
Creator: Clark, M.E.; Klonowska, A.; Thieman, S.B.; Giles, B.; Wall, J.D. & Fields, and M.W.
Partner: UNT Libraries Government Documents Department

Most Probable Number Rapid Viability PCR Method to Detect Viable Spores of Bacillus anthracis in Swab Samples

Description: This note presents a comparison of Most-Probable-Number Rapid Viability (MPN-RV) PCR and traditional culture methods for the quantification of Bacillus anthracis Sterne spores in macrofoam swabs generated by the Centers for Disease Control and Prevention (CDC) for a multi-center validation study aimed at testing environmental swab processing methods for recovery, detection, and quantification of viable B. anthracis spores from surfaces. Results show that spore numbers provided by the MPN RV-PCR method were in statistical agreement with the CDC conventional culture method for all three levels of spores tested (10{sup 4}, 10{sup 2}, and 10 spores) even in the presence of dirt. In addition to detecting low levels of spores in environmental conditions, the MPN RV-PCR method is specific, and compatible with automated high-throughput sample processing and analysis protocols.
Date: May 30, 2008
Creator: Letant, S E; Kane, S R; Murphy, G A; Alfaro, T M; Hodges, L; Rose, L et al.
Partner: UNT Libraries Government Documents Department

Deletion of ultraconserved elements yields viable mice

Description: Ultraconserved elements have been suggested to retainextended perfect sequence identity between the human, mouse, and ratgenomes due to essential functional properties. To investigate thenecessities of these elements in vivo, we removed four non-codingultraconserved elements (ranging in length from 222 to 731 base pairs)from the mouse genome. To maximize the likelihood of observing aphenotype, we chose to delete elements that function as enhancers in amouse transgenic assay and that are near genes that exhibit markedphenotypes both when completely inactivated in the mouse as well as whentheir expression is altered due to other genomic modifications.Remarkably, all four resulting lines of mice lacking these ultraconservedelements were viable and fertile, and failed to reveal any criticalabnormalities when assayed for a variety of phenotypes including growth,longevity, pathology and metabolism. In addition more targeted screens,informed by the abnormalities observed in mice where genes in proximityto the investigated elements had been altered, also failed to revealnotable abnormalities. These results, while not inclusive of all thepossible phenotypic impact of the deleted sequences, indicate thatextreme sequence constraint does not necessarily reflect crucialfunctions required for viability.
Date: July 15, 2007
Creator: Ahituv, Nadav; Zhu, Yiwen; Visel, Axel; Holt, Amy; Afzal, Veena; Pennacchio, Len A. et al.
Partner: UNT Libraries Government Documents Department

Cell wide responses to low oxygen exposure in Desulfovibriovulgaris Hildenborough

Description: The responses of the anaerobic, sulfate-reducing Desulfovibrio vulgaris Hildenborough to low oxygen exposure (0.1% O{sub 2}) were monitored via transcriptomics and proteomics. Exposure to 0.1% O{sub 2} caused a decrease in growth rate without affecting viability. A concerted up regulation in the predicted peroxide stress response regulon (PerR) genes was observed in response to the 0.1% O{sub 2} exposure. Several of these candidates also showed increases in protein abundance. Among the remaining small number of transcript changes was the up regulation of the predicted transmembrane tetraheme cytochrome c3 complex. Other known oxidative stress response candidates remained unchanged during this low O{sub 2} exposure. To fully understand the results of the 0.1% O{sub 2} exposure, transcriptomics and proteomics data were collected for exposure to air using a similar experimental protocol. In contrast to the 0.1% O{sub 2} exposure, air exposure was detrimental to both the growth rate and viability and caused dramatic changes at both the transcriptome and proteome levels. Interestingly, the transcripts of the predicted PerR regulon genes were down regulated during air exposure. Our results highlight the differences in the cell wide response to low and high O{sub 2} levels of in D. vulgaris and suggest that while exposure to air is highly detrimental to D. vulgaris, this bacterium can successfully cope with periodic exposure to low O{sub 2} levels in its environment.
Date: March 11, 2007
Creator: Mukhopadhyay, A.; Redding, A.; Joachimiak, M.; Arkin, A.; Borglin, S.; Dehal, P. et al.
Partner: UNT Libraries Government Documents Department