163 research outputs found

    Activated Carbon and Process for Making Same

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    A process is described for the manufacture of activated carbon in the form of a powder, as granules or as extrudates. The process includes treating a biomass feedstock, such as woods, coconut shells, fruit pits, peats, lignites and all ranks of coal with a processing agent and an activation agent. The processing agent may be a natural or synthetic monomer, oligomer, polymer or mixtures thereof capable of interacting or co-polymerizing with the biomass feedstock. The activation agent may be, for example, phosphoric acid, zinc chloride or mixtures thereof. A high surface area, high hardness extruded activated carbon may be produced by this process. The activated carbon is generally characterized by a BET surface area between 600-2500 m2 /g, a mesopore surface area between 80-900 m2 /g and for extruded or granular carbons, a Takeda hardness of between 10-50%

    Process for Removing Sulfur and Producing Enhanced Quality and Environmentally Acceptable Products for Energy Production from Coal

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    A process for producing enhanced quality adsorbent carbons and environmentally acceptable materials for energy production from coal includes an initial step of physically cleaning the coal to remove organic sulfur and mineral tailings. Next, a coal slurry of feedstock and water is prepared. Phosphoric acid is then mixed into the water of the coal slurry to provide by volume 15-85% and more preferably 50-85% phosphoric acid. The slurry is then heated and held in a temperature range between 85Ā° and 230Ā° C. for a period of at least five minutes to allow the phosphoric acid to penetrate deeply into the coal. Then the coal slurry is carbonized at a temperature of between 200Ā°-700Ā° C. for at least five to sixty minutes. The processing produces unique products including a low ash content, low sulfur content carbon solid, a tar with a sulfur content of less than 0.05% of the original feedstock and a gas product having a hydrogen to methane ratio of at least 4:1

    Not Representing Jesus: Fictional Approximations of Jesus in Contemporary Literature

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    In this thesis I begin by showing that historical, theological and fictional representations of Jesus are often based on reductive readings of the Gospel narrative and can lead to dogmatic statements about who Jesus was. I argue that some authors of contemporary fiction approach the biblical text in a more imaginative way, and that by misreading the Gospels they are able to approximate the teachings of Jesus, without depending on the creation of explicit Christ-figures. I have called these narratives fictional approximations of Jesus. I use Harold Bloomā€™s theory of misreading, George Steiner and Valentine Cunninghamā€™s notions of heresy, and Frank Kermode, Geoffrey Hartman, and Terry Wrightā€™s use of Midrash as a way to set out a methodology for reading contemporary fictions by Marilynne Robinson, Denis Johnson, Tim Winton and J. M. Coetzee in conjunction with the Gospel narratives. I show how they misread and rewrite the biblical text, explore the way in which they approximate Jesusā€™s teachings about forgiveness, love, grace, and hope, and how such misreadings allow for a fresh appreciation of the Bible. In the Introduction I show how Reza Aslanā€™s Zealot: The Life and Times of Jesus of Nazareth is a contemporary example of a reductive way of reading the Gospels and contrast that with the way the fictional approximations of Jesus misread the biblical narrative. In Chapter One I set out in more detail the parameters of the fictional approximation as a method of misreading that moves towards, but never arrives at, a complete identification with the source. In Chapters Two to Five I show how the fictional approximations of Jesus respond to the Gospel narratives by close-reading Robinsonā€™s Gilead and Home, Johnsonā€™s Angels and Jesusā€™ Son, Wintonā€™s Cloudstreet, and Coetzeeā€™s The Childhood of Jesus in parallel with relevant passages from the Bible

    Carbon Fiber Filters

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    Disclosed is a filter comprised of activated carbon fibers, wherein said filter has a Virus Removal Index (hereafter ā€œVRIā€) of at least about 99%, as measured in accordance with the test method described in the specification. The filter may comprise unbound fibers, or the fibers may be bound with a binder to form a composite of fibers. Also disclosed is a method of removing viruses from a liquid, the method comprising contacting the liquid with a filter comprising activated carbon fibers wherein said filter has a VRI of at least about 99%. Also described is an article of manufacture comprising: (a) a filter comprising activated carbon fibers, wherein said filter has a VRI of at least about 99%; and (b) instructions which inform a user that the filter may be used to remove viruses from a liquid

    The crystal structure of the catalytic domain of a eukaryotic guanylate cyclase

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    <p>Abstract</p> <p>Background</p> <p>Soluble guanylate cyclases generate cyclic GMP when bound to nitric oxide, thereby linking nitric oxide levels to the control of processes such as vascular homeostasis and neurotransmission. The guanylate cyclase catalytic module, for which no structure has been determined at present, is a class III nucleotide cyclase domain that is also found in mammalian membrane-bound guanylate and adenylate cyclases.</p> <p>Results</p> <p>We have determined the crystal structure of the catalytic domain of a soluble guanylate cyclase from the green algae <it>Chlamydomonas reinhardtii </it>at 2.55 ƅ resolution, and show that it is a dimeric molecule.</p> <p>Conclusion</p> <p>Comparison of the structure of the guanylate cyclase domain with the known structures of adenylate cyclases confirms the close similarity in architecture between these two enzymes, as expected from their sequence similarity. The comparison also suggests that the crystallized guanylate cyclase is in an inactive conformation, and the structure provides indications as to how activation might occur. We demonstrate that the two active sites in the dimer exhibit positive cooperativity, with a Hill coefficient of ~1.5. Positive cooperativity has also been observed in the homodimeric mammalian membrane-bound guanylate cyclases. The structure described here provides a reliable model for functional analysis of mammalian guanylate cyclases, which are closely related in sequence.</p

    ***TEST SUBMISSION*** BMJ-15: Acceptance within last 3 months (01/03/2020); Online publication within 12 months (10/12/2020); Embargo (10/09/2021) less than 12 months from pub date; VoR

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    From UAT Test publisher via Jisc Publications RouterHistory: accepted 2020-03-01, epub 2020-12-10Article version: VoRPublication status: PublishedAbstract: TEST: THIS IS A PUBLICATIONS ROUTER TEST SUBMISSION. Objectives: To quantify post-colonoscopy colorectal cancer (PCCRC) rates in England by using recent World Endoscopy Organisation guidelines, compare incidence among colonoscopy providers, and explore associated factors that could benefit from quality improvement initiatives. Design: Population based cohort study. Setting: National Health Service in England between 2005 and 2013. Population: All people undergoing colonoscopy and subsequently diagnosed as having colorectal cancer up to three years after their investigation (PCCRC-3yr). Main outcome measures: National trends in incidence of PCCRC (within 6-36 months of colonoscopy), univariable and multivariable analyses to explore factors associated with occurrence, and funnel plots to measure variation among providers. Results: The overall unadjusted PCCRC-3yr rate was 7.4% (9317/126 152), which decreased from 9.0% in 2005 to 6.5% in 2013 (P<0.01). Rates were lower for colonoscopies performed under the NHS bowel cancer screening programme (593/16 640, 3.6%), while they were higher for those conducted by non-NHS providers (187/2009, 9.3%). Rates were higher in women, in older age groups, and in people with inflammatory bowel disease or diverticular disease, in those with higher comorbidity scores, and in people with previous cancers. Substantial variation in rates among colonoscopy providers remained after adjustment for case mix. Conclusions: Wide variation exists in PCCRC-3yr rates across NHS colonoscopy providers in England. The lowest incidence was seen in colonoscopies performed under the NHS bowel cancer screening programme. Quality improvement initiatives are needed to address this variation in rates and prevent colorectal cancer by enabling earlier diagnosis, removing premalignant polyps, and therefore improving outcomes

    Homing endonuclease I-TevIII: dimerization as a means to a double-strand break

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    Homing endonucleases are unusual enzymes, capable of recognizing lengthy DNA sequences and cleaving site-specifically within genomes. Many homing endonucleases are encoded within group I introns, and such enzymes promote the mobility reactions of these introns. Phage T4 has three group I introns, within the td, nrdB and nrdD genes. The td and nrdD introns are mobile, whereas the nrdB intron is not. Phage RB3 is a close relative of T4 and has a lengthier nrdB intron. Here, we describe I-TevIII, the Hā€“Nā€“H endonuclease encoded by the RB3 nrdB intron. In contrast to previous reports, we demonstrate that this intron is mobile, and that this mobility is dependent on I-TevIII, which generates 2-nt 3ā€² extensions. The enzyme has a distinct catalytic domain, which contains the Hā€“Nā€“H motif, and DNA-binding domain, which contains two zinc fingers required for interaction with the DNA substrate. Most importantly, I-TevIII, unlike the Hā€“Nā€“H endonucleases described so far, makes a double-strand break on the DNA homing site by acting as a dimer. Through deletion analysis, the dimerization interface was mapped to the DNA-binding domain. The unusual propensity of I-TevIII to dimerize to achieve cleavage of both DNA strands underscores the versatility of the Hā€“Nā€“H enzyme family
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