10 research outputs found
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GEOLOGIC SCREENING CRITERIA FOR SEQUESTRATION OF CO2 IN COAL: QUANTIFYING POTENTIAL OF THE BLACK WARRIOR COALBED METHANE FAIRWAY, ALABAMA
Sequestration of CO{sub 2} in coal has potential to reduce greenhouse gas emissions from coal-fired power plants while enhancing coalbed methane recovery. Data from more than 4,000 coalbed methane wells in the Black Warrior basin of Alabama provide an opportunity to quantify the carbon sequestration potential of coal and to develop a geologic screening model for the application of carbon sequestration technology. This report summarizes stratigraphy and sedimentation, structural geology, geothermics, hydrology, coal quality, gas capacity, and production characteristics of coal in the Black Warrior coalbed methane fairway and the implications of geology for carbon sequestration and enhanced coalbed methane recovery. Coal in the Black Warrior basin is distributed among several fluvial-deltaic coal zones in the Lower Pennsylvanian Pottsville Formation. Most coal zones contain one to three coal beds that are significant targets for coalbed methane production and carbon sequestration, and net coal thickness generally increases southeastward. Pottsville strata have effectively no matrix permeability to water, so virtually all flow is through natural fractures. Faults and folds influence the abundance and openness of fractures and, hence, the performance of coalbed methane wells. Water chemistry in the Pottsville Formation ranges from fresh to saline, and zones with TDS content lower than 10,000 mg/L can be classified as USDW. An aquifer exemption facilitating enhanced recovery in USDW can be obtained where TDS content is higher than 3,000 mg/L. Carbon dioxide becomes a supercritical fluid above a temperature of 88 F and a pressure of 1,074 psi. Reservoir temperature exceeds 88 F in much of the study area. Hydrostatic pressure gradients range from normal to extremely underpressured. A large area of underpressure is developed around closely spaced longwall coal mines, and areas of natural underpressure are distributed among the coalbed methane fields. The mobility and reactivity of supercritical CO{sub 2} in coal-bearing strata is unknown, and potential exists for supercritical conditions to develop below a depth of 2,480 feet following abandonment of the coalbed methane fields. High-pressure adsorption isotherms confirm that coal sorbs approximately twice as much CO{sub 2} as CH{sub 4} and approximately four times as much CO{sub 2} as N{sub 2}. Analysis of isotherm data reveals that the sorption performance of each gas can vary by a factor of two depending on rank and ash content. Gas content data exhibit extreme vertical and lateral variability that is the product of a complex burial history involving an early phase of thermogenic gas generation and an ongoing stage of late biogenic gas generation. Production characteristics of coalbed methane wells are helpful for identifying areas that are candidates for carbon sequestration and enhanced coalbed methane recovery. Many geologic and engineering factors, including well construction, well spacing, and regional structure influence well performance. Close fault spacing limits areas where five-spot patterns may be developed for enhanced gas recovery, but large structural panels lacking normal faults are in several gas fields and can be given priority as areas to demonstrate and commercialize carbon sequestration technology in coalbed methane reservoirs
Development of a facile fluorophosphonate-functionalised titanium surface for potential orthopaedic applications
Background: Aseptic loosening of total joint replacements (TJRs) continues to be the main cause of implant failures. The socioeconomic impact of surgical revisions is hugely significant; in the United Kingdom alone, it is estimated that £137 m is spent annually on revision arthroplasties. Enhancing the longevity of titanium implants will help reduce the incidence and overall cost of failed devices. Methods: In realising the development of a superior titanium technology, we exploited the natural affinity of titanium for phosphonic acids and developed a facile means of coating the metal with (3S)1-fluoro-3-hydroxy-4-(oleoyloxy)butyl-1-phosphonate (FHBP), a phosphatase-resistant analogue of lysophosphatidic acid (LPA). Importantly LPA and selected LPA analogues like FHBP synergistically cooperate with calcitriol to promote human osteoblast formation and maturation. Results: Herein, we provide evidence that simply immersing titanium in aqueous solutions of FHBP afforded a surface that was superior to unmodified metal at enhancing osteoblast maturation. Importantly, FHBP-functionalised titanium remained stable to 2 years of ambient storage, resisted ∼35 kGy of gamma irradiation and survived implantation into a bone substitute (Sawbone™) and irrigation. Conclusion: The facile step we have taken to modify titanium and the robustness of the final surface finish are appealing properties that are likely to attract the attention of implant manufacturers in the future. The translational potential of this article: We have generated a functionalised titanium (Ti) surface by simply immersing Ti in aqueous solutions of a bioactive lipid. As a facile procedure it will have greater appeal to implant manufacturers compared to onerous and costly developmental processes
Finishing the euchromatic sequence of the human genome
The sequence of the human genome encodes the genetic instructions for human physiology, as well as rich information about human evolution. In 2001, the International Human Genome Sequencing Consortium reported a draft sequence of the euchromatic portion of the human genome. Since then, the international collaboration has worked to convert this draft into a genome sequence with high accuracy and nearly complete coverage. Here, we report the result of this finishing process. The current genome sequence (Build 35) contains 2.85 billion nucleotides interrupted by only 341 gaps. It covers ∼99% of the euchromatic genome and is accurate to an error rate of ∼1 event per 100,000 bases. Many of the remaining euchromatic gaps are associated with segmental duplications and will require focused work with new methods. The near-complete sequence, the first for a vertebrate, greatly improves the precision of biological analyses of the human genome including studies of gene number, birth and death. Notably, the human enome seems to encode only 20,000-25,000 protein-coding genes. The genome sequence reported here should serve as a firm foundation for biomedical research in the decades ahead
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GEOLOGIC SCREENING CRITERIA FOR SEQUESTRATION OF CO2 IN COAL: QUANTIFYING POTENTIAL OF THE BLACK WARRIOR COALBED METHANE FAIRWAY, ALABAMA
Sequestration of CO{sub 2} in coal has potential benefits for reducing greenhouse gas emissions from the highly industrialized Carboniferous coal basins of North America and Europe and for enhancing coalbed methane recovery. Hence, enhanced coalbed methane recovery operations provide a basis for a market-based environmental solution in which the cost of sequestration is offset by the production and sale of natural gas. The Black Warrior foreland basin of west-central Alabama contains the only mature coalbed methane production fairway in eastern North America, and data from this basin provide an excellent basis for quantifying the carbon sequestration potential of coal and for identifying the geologic screening criteria required to select sites for the demonstration and commercialization of carbon sequestration technology. Coalbed methane reservoirs in the upper Pottsville Formation of the Black Warrior basin are extremely heterogeneous, and this heterogeneity must be considered to screen areas for the application of CO{sub 2} sequestration and enhanced coalbed methane recovery technology. Major screening factors include stratigraphy, geologic structure, geothermics, hydrogeology, coal quality, sorption capacity, technology, and infrastructure. Applying the screening model to the Black Warrior basin indicates that geologic structure, water chemistry, and the distribution of coal mines and reserves are the principal determinants of where CO{sub 2} can be sequestered. By comparison, coal thickness, temperature-pressure conditions, and coal quality are the key determinants of sequestration capacity and unswept coalbed methane resources. Results of this investigation indicate that the potential for CO{sub 2} sequestration and enhanced coalbed methane recovery in the Black Warrior basin is substantial and can result in significant reduction of greenhouse gas emissions while increasing natural gas reserves. Coal-fired power plants serving the Black Warrior basin in Alabama emit approximately 31 MMst (2.4 Tcf) of CO{sub 2} annually. The total sequestration capacity of the Black Warrior coalbed methane fairway at 350 psi is about 189 MMst (14.9 Tcf), which is equivalent to 6.1 years of greenhouse gas emissions from the coal-fired power plants. Applying the geologic screening model indicates that significant parts of the coalbed methane fairway are not accessible because of fault zones, coal mines, coal reserves, and formation water with TDS content less than 3,000 mg/L. Excluding these areas leaves a sequestration potential of 60 MMst (4.7 Tcf), which is equivalent to 1.9 years of emissions. Therefore, if about10 percent of the flue gas stream from nearby power plants is dedicated to enhanced coalbed methane recovery, a meaningful reduction of CO{sub 2} emissions can be realized for nearly two decades. If the fresh-water restriction were removed for the purposes of CO{sub 2} sequestration, an additional 10 MMst (0.9 Tcf) of CO{sub 2} could feasibly be sequestered. The amount of unswept coalbed methane in the fairway is estimated to be 1.49 Tcf at a pressure of 50 psi. Applying the screening model results in an accessible unswept gas resource of 0.44 Tcf. Removal of the fresh-water restriction would elevate this number to 0.57 Tcf. If a recovery factor of 80 percent can be realized, then enhanced recovery activities can result in an 18 percent expansion of coalbed methane reserves in the Black Warrior basin
Micro-Targeting, Voter Intelligence and Data Protection Law: Can Candidates and Political Parties Do in Europe What They Do in North America?
Antagonism of Ang-Tie2 and Dll4-Notch signaling has opposing effects on tumor endothelial cell proliferation, evidenced by a new flow cytometry method
Temperature stability of proteins essential for the intracellular survival of Mycobacterium tuberculosis
Validation of a prognostic multi-gene signature in high-risk neuroblastoma using the high throughput digital NanoString nCounter™ system
Microarray‐based molecular signatures have not been widely integrated into neuroblastoma diagnostic classification systems due to the complexities of the assay and requirement for high‐quality RNA. New digital technologies that accurately quantify gene expression using RNA isolated from formalin‐fixed paraffin embedded (FFPE) tissues are now available. In this study, we describe the first use of a high‐throughput digital system to assay the expression of genes in an “ultra‐high risk” microarray classifier in FFPE high‐risk neuroblastoma tumors. Customized probes corresponding to the 42 genes in a published multi‐gene neuroblastoma signature were hybridized to RNA isolated from 107 FFPE high‐risk neuroblastoma samples using the NanoString nCounter™ Analysis System. For classification of each patient, the Pearson's correlation coefficient was calculated between the standardized nCounter™ data and the molecular signature from the microarray data. We demonstrate that the nCounter™ 42‐gene panel sub‐stratified the high‐risk cohort into two subsets with statistically significantly different overall survival (p = 0.0027) and event‐free survival (p = 0.028). In contrast, none of the established prognostic risk markers (age, stage, tumor histology, MYCN status, and ploidy) were significantly associated with survival. We conclude that the nCounter™ System can reproducibly quantify expression levels of signature genes in FFPE tumor samples. Validation of this microarray signature in our high‐risk patient cohort using a completely different technology emphasizes the prognostic relevance of this classifier. Prospective studies testing the prognostic value of molecular signatures in high‐risk neuroblastoma patients using FFPE tumor samples and the nCounter™ System are warranted