Unlocking the potential of RNA interference as a therapeutic tool

The existence of an intrinsic biochemical pathway enabling specified regulation of gene expression was unheard of until the final years of the last decade. The identification of ribonucleic acid interference (RNAi) in mammalian cells has nowadays become of extreme importance in the field of functional genomics and translational medicine. The advent of RNAi technology has brought to the scientific research and pharmaceutical communities the ability to regulate expression of any desired gene in a reproducible manner. Consequently, such technology may be utilised in the design of novel therapeutics for clinical conditions having dys-regulated gene expression. Since most RNAi-based therapies in the drug development pipeline of pharmaceutical companies utilise short interfering RNA (siRNA), this review will focus on the role of siRNA in drug development.peer-reviewe

Plio-Pleistocene Depositional Sequences of the Southwestern Louisiana Continental Shelf and Slope: Geologic Framework, Sedimentary Facies and Hydrocarbon Distribution

The Plio-Pleistocene hydrocarbon fairway of offshore Louisiana is restricted to the outer continental shelf and upper continental slope where a thick wedge of nearshore and deep marine sediments was deposited. Electric logs, paleontological reports, and seismic profiles form the basis for (1) dividing the wedge of Plio-Pleistocene strata into eight genetic sequences, (2) establishing the structural framework, (3) determining the timing of deformation, and (4) mapping the principal depositional systems of the West Cameron and western Garden Banks areas during the past five million years. Sedimentary facies and structural styles in this part of the basin are highly variable owing to contemporaneous sea-level fluctuations, salt migration, and shifting sites of deltaic, shelf, and slope sedimentation. The resulting complex geologic history of this part of the basin directly controlled the generation, migration, and entrapment of hydrocarbons. The early Pliocene was a period of continental platform inundation and deposition of a thick succession of marine mudstones. About 3 Ma, this monotonous accumulation of deep-water mudstone was interrupted by deposition of sand-rich submarine channels and fans associated with a lowering of sea level. These lowstand deposits extended at least 55 mi (90 km) basinward of the paleomargin. Overlying Pleistocene sediments were deposited mainly by prograding mud-rich fluvial-deltaic systems of moderate size. These rivers and shelf-edge deltas constructed a broad continental platform that buried the submarine fans and prograded the shelf margin approximately 70 mi (110 km) basinward. During this rapid outbuilding, slumping and other gravity-driven mass transport processes removed sand-rich delta-front sediments from unstable shelf margins and redeposited them on the continental slope.Bureau of Economic Geolog

Plio-Pleistocene Depositional Sequences of the Southwestern Louisiana Continental Shelf and Slope: Geologic Framework, Sedimentary Facies and Hydrocarbon Distribution

The Plio-Pleistocene hydrocarbon fairway of offshore Louisiana is restricted to the outer continental shelf and upper continental slope where a thick wedge of nearshore and deep marine sediments was deposited. Electric logs, paleontological reports, and seismic profiles form the basis for (1) dividing the wedge of Plio-Pleistocene strata into eight genetic sequences, (2) establishing the structural framework, (3) determining the timing of deformation, and (4) mapping the principal depositional systems of the West Cameron and western Garden Banks areas during the past five million years. Sedimentary facies and structural styles in this part of the Gulf Coast basin are highly variable owing to contemporaneous sea-level fluctuations, salt migration, and shifting sites of deltaic, shelf, and slope sedimentation. The resulting complex geologic history of this part of the basin was interpreted to determine what controlled the generation, migration, and entrapment of hydrocarbons. The early Pliocene was a period of continental platform inundation and deposition of a thick succession of marine mudstones. About 3 million years ago, this monotonous accumulation of deep-water mudstone was interrupted by deposition of sand-rich submarine channels and fans associated with a lowering of sea level. These lowstand deposits extended at least 55 miles (90 km) basinward of the paleomargin. Overlying Pleistocene sediments were deposited mainly by prograding mud-rich fluvial-deltaic systems of moderate size. These rivers and shelf-edge deltas constructed a broad continental platform that buried the submarine fans and prograded the shelf margin approximately 70 miles (110 km) basinward. During this rapid outbuilding, slumping and other gravity-driven mass transport processes removed sand-rich delta-front sediments from unstable shelf margins and redeposited them on the continental slope.Bureau of Economic Geolog

Beyond Truth-in-Lending - Federal Regulation of Debt Collection.

Abstract Forthcoming

Retention of resin restorations by means of enamel etching and by pins

Indiana University-Purdue University Indianapolis (IUPUI)An investigation was conducted into the effect of acid etching of the enamel and the use of pins on the retention of direct filling resins when used for restoration of fractured incisor teeth. The retention secured by these techniques as related to the cavity design also was studied. Four different cavity preparations were used. The retention of the resin in all four was compared when there was no pretreatment of the enamel, when the enamel was etched by 50 per cent phosphoric acid, and when pins were used for retention. Retention was assessed on the basis of resistance of the restoration to displacement by a lingual force. No significant difference was observed in retention as related to cavity design in the control specimens. In all four cavity preparations, acid etching of the enamel and the use of two retentive pins increased the resistance of the restorations to displacement. (However; when only one "L" shaped retentive pin was employed in Conjunction with a flat incisal preparation the force required to accomplish displacement was no greater than for controls.) The acid etch technique when employed with a cavity preparation that extended 1.7 mm. or more onto the lingual surface of the enamel generally offered a higher resistance to lingual force than double pin retained restorations. There was no significant difference between the resistance offered by a circumferential preparation when the resin was retained by either acid etching or by two pins. In the acid etch technique the enamel surface area and its distribution are important factors in retention

Coordination of Geological and Engineering Research in Support of Gulf Coast Co-Production Program

More than 150 gas fields were reviewed, and 25 fields were selected using modified specific selection criteria as outlined by Gregory and others (1983). Further evaluation of these fields is necessary to obtain a new ranking for Gregory's class A, B, and C divisions. A list of the 25 most favorable fields was sent to Eaton Operating Co., who were to approach likely companies to initiate joint ventures in co-production. Four reservoirs containing dispersed gas were examined for their co-production potential. Reservoirs in Port Acres and Ellis fields produce from the Hackberry Member of the Oligocene Frio Formation, and two reservoirs in Esther field produce from the lower Miocene Planulina Zone. Log-pattern and lithofacies maps, together with stratigraphic position, suggest that the reservoirs are in ancient submarine-fan deposits. Dip-elongate, channel-fill sands are characteristic; reservoir sands pinch out along strike. Growth faults, common in the submarine slope setting, form updip and downdip boundaries, producing combination traps. In Ellis field, co-production accounts for 300 Mcf (8.5 x 106 m3) of gas per day. Port Acres field contains the largest remaining reserves, but other technical and economic factors limit co-production there. Recent drilling has extended primary production and delayed co-production in Esther field. The Gas Research Institute requested that further work on the selection and evaluation of potential co-production gas fields be terminated because funds were required for the Port Arthur project.Bureau of Economic Geolog

Information on commercial disposal facilities that may have received offshore drilling wastes.

The U.S. Environmental Protection Agency (EPA) is developing regulations that would establish requirements for discharging synthetic-based drill cuttings from offshore wells into the ocean. Justification for allowing discharges of these cuttings is that the environmental impacts from discharging drilling wastes into the ocean may be less harmful than the impacts from hauling them to shore for disposal. In the past, some onshore commercial facilities that disposed of these cuttings were improperly managed and operated and left behind environmental problems. This report provides background information on commercial waste disposal facilities in Texas, Louisiana, California, and Alaska that received or may have received offshore drilling wastes in the past and are now undergoing cleanup

CO2 SEQUESTRATION POTENTIAL OF TEXAS LOW-RANK COALS

The objectives of this project are to evaluate the feasibility of carbon dioxide (CO{sub 2}) sequestration in Texas low-rank coals and to determine the potential for enhanced coalbed methane (CBM) recovery as an added benefit of sequestration. The main objectives for this reporting period were to work on Tasks 1 and 2, which consisted of the following subtasks: review literature on CO{sub 2} sequestration and the effect of CO{sub 2} injection on methane production from coalbeds; acquire information on power plant flue gas emissions; acquire data on Texas coal occurrences and properties and formation water quality; construct a digital base map; and select geographic areas and geologic formations for study. Flue gas information, including volumes and compositions, were obtained for major Texas power plants and other industrial sources, such as cement plants. We evaluated and obtained computer mapping software and began building a digital base map that will be used to depict industrial emissions, coal occurrence, and water quality information. Digital data sets allow us to superpose data for visualization and for assessment of CO{sub 2}sequestration issues

CO2 Sequestration Potential of Texas Low-Rank Coals

The objectives of this project are to evaluate the feasibility of carbon dioxide (CO{sub 2}) sequestration in Texas low-rank coals and to determine the potential for enhanced coalbed methane (ECBM) recovery as an added benefit of sequestration. In this reporting period we revised all of the economic calculations, participated in technology transfer of project results, and began working on project closeout tasks in anticipation of the project ending December 31, 2005. In this research, we conducted five separate simulation investigations, or cases. These cases are (1) CO{sub 2} sequestration base case scenarios for 4,000-ft and 6,200-ft depth coal beds in the Lower Calvert Bluff Formation of east-central Texas, (2) sensitivity study of the effects of well spacing on sequestration, (3) sensitivity study of the effects of injection gas composition, (4) sensitivity study of the effects of injection rate, and (5) sensitivity study of the effects of coal dewatering prior to CO{sub 2} injection/sequestration. Results show that, in most cases, revenue from coalbed methane production does not completely offset the costs of CO{sub 2} sequestration in Texas low-rank coals, indicating that CO{sub 2} injection is not economically feasible for the ranges of gas prices and carbon credits investigated. The best economic performance is obtained with flue gas (13% CO{sub 2} - 87% N{sub 2}) injection, as compared to injection of 100% CO{sub 2} and a mixture of 50% CO{sub 2} and 50% N{sub 2}. As part of technology transfer for this project, we presented results at the West Texas Geological Society Fall Symposium in October 2005 and at the COAL-SEQ Forum in November 2005

Geologic Evaluation of Critical Production Parameters for Coalbed Methane Resources: Part 1, San Juan Basin

The Fruitland Formation in the San Juan Basin is the major producer of coalbed methane in the Western U.S. Forty-three to forty-nine Tcf of methane occur in 245 billion short tons of Fruitland coal at depths between 400 and 4,200 ft. Thickest Fruitland coal seams trend northwest and occur in the northern part of the basin, northeast of a syndepositional, structural hinge line; they occur in coastal plain facies southwest of Pictured Cliffs barrier/strandplain sandstones. South of the hinge line, northeast-trending coal seams occur in floodplain facies between northeast-trending Fruitland fluvial systems. Face cleat trends in Fruitland coal seams are predominantly northeast in the southern two-thirds of the basin and northwest but variable in the northern third. Suggested targets for enhanced coalbed permeability are tectonic fractures and fractures associated with subtle folds. Fruitland Formation waters are evolved meteoric waters; water composition reflects hydrologic setting. Waters in the north-central San Juan Basin have high alkalinity and low chlorinity; waters in the southern part are Na-Cl type. Distribution of low-chloride ground water in the Fruitland Formation in the north-central basin coincides with the overpressured area and with flow patterns inferred from the head map. The Fruitland Formation acts regionally as a single hydrologic unit or homogeneous aquifer, but large pressure gradients locally indicate that Fruitland strata may be hydraulically disconnected and behave at the field scale as compartmentalized aquifers. Hydrologic studies defined reservoir characteristics and permeability boundaries in the Fruitland Formation. Geologic and hydrologic parameters were used to divide the San Juan Basin into areas in which coal beds have similar reservoir characteristics. Coalbed wells have negative declines early in their production history followed by exponential decline rates at less than 5 percent/year. Sandstone wells that exhibit coal-decline behavior probably are producing coalbed methane indirectly from coal seams.Bureau of Economic Geolog