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Injecting CO2 into depleted oil reservoirs to extract additional crude oil is a common enhanced oil recovery (CO2-EOR) technique. However, little is known about how in situ microbial communities may be impacted by CO2 flooding, or if any permanent microbiological changes occur after flooding has ceased. Formation water was collected from an oil field that was flooded for CO2-EOR in the 1980s, including samples from areas affected by or outside of the flood region, to determine the impacts of CO2-EOR on reservoir microbial communities. Archaea, specifically methanogens, were more abundant than bacteria in all samples, while identified bacteria exhibited much greater diversity than the archaea. Microbial communities in CO2-impacted and non-impacted samples did not significantly differ (ANOSIM: Statistic R = -0.2597, significance = 0.769). However, several low abundance bacteria were found to be significantly associated with the CO2-affected group; very few of these species are known to metabolize CO2 or are associated with CO2-rich habitats. Although this study had limitations, on a broad scale, either the CO2 flood did not impact the microbial community composition of the target formation, or microbial communities in affected wells may have reverted back to pre-injection conditions over the ca. 40 years since the CO2-EOR., Microbial community composition was compared between samples affected by a CO2-EOR flood and those from areas that were outside or stratigraphically above the flood region to determine if CO2-EOR flooding impacted the microbial community, or if the reservoir was able to “reset” back to pre-flood conditions.

Base catalyzed reaction of heterocyclic bases with R-(+)-glycidol gives heteroarylpropane-2,3-diols which are functionalized to the 3-O-dimethoxytrityl-2-O-phosphoramidites. A dimethoxytrityl-glycidol is reacted with alkyl or aryl Grignard reagents and then phosphitylated to yield 1-O-dimethoxytrityl-2-phosphoramidites. These compounds can be used for combinatorial oligomer synthesis.

A series of 4-(1-alkynyl)-2(1H)-pyrimidinone ribonucleosides were synthesized from the Pd-catalyzed coupling of terminal alkynes to the 4-chloropyrimidin-2-one ribonucleoside (2). These compounds were hydrated, using three different methods, to afford the 4-(2-oxoalkylidene)-2(1H)-pyrimidinones. The 4-enol-pyrimidin-2-one structure of the title compounds offers functional groups with the potential for Watson-Crick hydrogen bonding.

A convergent and general approach to synthesizing 2′-O-Methylpyrimidine ribonucleosides 4a-e, 6,7 on a multigram scale is described which begins with an improved procedure for making larger quantities of 2-O-methyl-1,3,5-tri-O-benzoyl-α-D-ribose. The sugar was reacted with the desired silylated pyrimidines at room temperature under Vorbruggen conditions. The crude products contained less than 10% of the α anomers and the desired β anomers were isolated by crystallization. The blocked nucleosides were then deprotected and isolated by standard methods.

A case of xanthogranulomatous cholecystitis is presented with a brief review of its sonographic and magnetic resonance features. These imaging features are also compared to those seen in gallbladder adenomyomatosis and gallbladder carcinoma. While there are many overlapping imaging findings in these entities, it is important to recognize distinguishing characteristics so a correct surgical approach is chosen. Laparoscopic cholecystectomy attempted with existing xanthogranulomatous cholecystitis has an increased surgical complication rate compared to open cholecystectomy and often necessitates intraoperative conversion to open cholecystectomy.

The synthesis of several 2′-deoxy-3-alkyl(aryl)-3-deazaguanosines and of their heterocyclic aglycone is described. The 2-(1-napthyl)ethyl substituent group induces an unnatural 3′-endo/high-anti (-sc) conformation of the nucleoside.

A convergent and general approach to synthesizing 2′-O-Methylpyrimidine ribonucleosides 4a-e, 6,7 on a multigram scale is described which begins with an improved procedure for making larger quantities of 2-O-methyl-1,3,5-tri-O-benzoyl-α-D-ribose. The sugar was reacted with the desired silylated pyrimidines at room temperature under Vorbruggen conditions. The crude products contained less than 10% of the α anomers and the desired β anomers were isolated by crystallization. The blocked nucleosides were then deprotected and isolated by standard methods.

The patient was an 8-year-old girl who was referred to a physical therapist by her pediatrician for a chief complaint of worsening proximal right calf pain and progressive right-sided toe walking for the past 6 weeks. Due to concern that the patient's symptoms were nonmusculoskeletal in nature, the physical therapist discussed the history and physical examination findings with the patient's pediatrician and an orthopaedic surgeon. Subsequent magnetic resonance imaging and percutaneous biopsy led to a diagnosis of a low-flow venolymphatic malformation of the proximal gastrocnemius muscle.

If geology is to be presented effectively to students with diverse backgrounds, interests, and curricula, it should be customized to provide the most useful course for each student. The self-instruction mode such as the Keller Plan (Personalized System of Instruction) offers far more flexibility to the instructor than the traditional lecture method and yet retains the valuable aspects of geology such as laboratory exercises and field trips. This paper gives an outline for a self-instruction course in geological oceanography having no prerequisite of basic geology as an example for other courses having specific goals.

The drill hole for the Cajon Pass Scientific Drilling Project was designed uniquely to accomplish specific science experiments. Special consideration was given to drilling practices for hole size, spot coring, deviation from the vertical, chemical and physical properties of the drilling fluids and pipe lubricants, monitoring mud logging and drilling parameters, and procedures for handling of cores and cuttings samples. Phase I of drilling reached a depth of 2115 m.

Perhaps by the conclusion of this paper, you will believe that somehow an obstetrician and a pediatrician have mistakenly wandered into your meeting. We propose to tell you of the birth and early development of a program which involved protracted labor, threatened for a time to be triplets and, now, as a slightly schizophrenic individual, is struggling toward maturity. The United States Continental Scientific Drilling Program has had more than the normal number of parents, all of whom retain an interest in its growth and well being, and with whose guidance and support it seems to be developing well.

In December 198 6, Deep Observation and Sampling of the Earth’s Continental Crust, Inc. (DOSECC), began Phase I of its first major scientific drilling project at Cajon Pass, California. Scientific experimentation for this project is designed and conducted by geologists from universities and government laboratories. The project’s primary goal is collection of borehole data to provide greater insight into the dynamics of the active San Andreas fault.

The present effort focused on three objectives: (1) To estimate the training effectiveness of Computer Assisted Map Maneuver System (CAMMS). This objective was aimed at the type and amount of performance improvement that can be produced with a battle simulation (i.e., CAMMS). Implicit in this objective is the development of command group performance assessment procedures and feedback mechanisms that would allow the command group to diagnose their training strengths and weaknesses. (2) To refine performance measurement procedures. This objective was designed to assist in the development of more valid and sensitive means of measuring the proficiency level of battalion command groups. (3) To estimate the feasibility of continuing to utilize CAMMS as a vehicle for investigating command group training. An important objective of this effort was to determine if CAMMS has the sensitivity and capability required of a research tool for providing sufficient data to answer some of the unanswered questions associated with command group training and to ascertain what might be necessary to enhance its utility for that purpose.

Chemically, the sediments from the Weddell Sea differ from the sediments of the Amundsen, Bellingshausen, and Ross Seas. As a group, they have a similar concentration of Cr, Ni, Al, and Co, but the Weddell Sea sediments are considerably lower in Mn, Fe, Ti, V, and Cu. When compared to crustal abundance figures, they are lower in Mg, Ni, Mn, Fe, Al, and Ti; higher in Zr, B, V, and Cu; and similar in content in Cr and Co. The Mn/Fe, Mn/Ti, Mn/Al, Ni/Al, and Fe/Al ratios show great differences between glacial marine and "normal" deep sea sediments. Somewhat less but still useful differences exist between V/Al and Co/Al ratios. Ternary diagram plots of V, Cu, and Co+Ni content delineate distinct fields for glacial marine, pelagic, and shallow water sediments. For pelagic vs. glacial marine sediments a ternary plot of Al, Fe, and Mn+Ti shows a restriction of glacial marine sediments to a narrow field along the Al-Fe join. As is well known, the type of sediment surrounding Antarctica and which is found in the Weddell Sea area is distinctive among marine sediments. These deposits have the mechanical characteristics of tills. The poor sorting is unusual for marine deposits. Marine currents have had little or no sorting effort on these sediments. Major characteristics of these sediments are the freshness and angularity of the detrital material. The heavy minerals indicate that the Weddell Sea sediments are derived predominately from an area of metamorphic rocks and transported and(or) rafted across the area of the Filchner Ice Shelf by floating ice. This mode of transport is indicated by the polymodal size distribution of the sediments.

This study concerned how information extraction and assimilation from dynamic visual displays are affected by three amounts of information presented (12, 18, or 24 units), three types of updating changes (“Adding”, “Moving,“ or “Removing“ units), three extents of changes (2, 4, or 6 units), and three ways of indicating updates (double-cue coding, single-cue coding and history hard copy.). Subjects were presented successive pairs of slides with the second slide containing the updates. Speed and accuracy of extracing and assimilating the updated information were recorded. It was found that: 1) Double-cue improved extraction 97%; assimilation 57%. 2) Single-cue coding improved extraction 68%, assimilation 47%. 3) Hard copy history did not aid extraction; improved assimilation only slightly. 4) Increasing the amount of information and extent of change degraded extraction and assimilation. 5) For assimilation, double-cue coding nullified the degrading effects of increasing amount of information. 6) In both tasks, the “Removed“ condition was easiest, “Added“ next, and the “Moved“ condition most difficult. Results indicate that major performance improvement can be achieved through coding without use of relatively costly color techniques.

The Interagency Coordinating Group on Continental Scientific Drilling develops policy to guide long-term drilling plans for the Department of Energy, National Science Foundation, and U.S. Geological Survey. ICG has already cooperated on several drilling projects, such as those at Salton Sea, Long Valley, and Cajon Pass in California, and Valles caldera in New Mexico. Congress will soon pass the Continental Scientific Drilling and Exploration Act, S. 52 and H.R. 2737. The bill requires ICG to prepare a report that outlines a national program of scientific drilling.

The Continental Scientific Drilling Committee (CSDC) was established by the National Academy of Sciences-National Research Council in December 1979 to provide communication, coordination, and advice on scientific utilization of continental drill holes and to encourage implementation of drilling research on basement structures and deep continental basins, thermal regimes, mineral resources, and earthquakes (as described in the report, Continental Scientific Drilling Program, by the U.S. Geodynamics Committee, 1979). The committee has encouraged add-on experiments to mission-oriented drilling activities of government and industry and the development of plans for drilling of dedicated holes for specific scientific investigations where no appropriate holes are available.