2,162 research outputs found

    Decontamination of petroleum products Patent

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    Decontamination of petroleum products with hone

    Rugged pressed disk electrode has low contact potential

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    Pressed-disk electrode with low contact potential monitors physiological processes. It consists of silver and silver chloride combined with bentonitic clay. The clay affords a surface that permits use over extended periods without contact deterioration

    Pressed disc type sensing electrodes with ion- screening means Patent

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    Characteristics of pressed disc electrode for biological measurement

    A new high-speed solar radio spectrograph for meter and decameter wavelengths

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    The design and characteristics of a high resolution, digital solar spectrograph are discussed. The spectrometer operates in the 10 to 80 MHz range. The primary considerations in the design of the spectrograph were: (1) optimun sensitivity, (2) wide dynamic range, (3) flexibility in time and frequency resolution, and (4) modern data handling techniques with a simple computer interface

    Remembering Forward: Neural Correlates of Memory and Prediction in Human Motor Adaptation

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    We used functional MR imaging (FMRI), a robotic manipulandum and systems identification techniques to examine neural correlates of predictive compensation for spring-like loads during goal-directed wrist movements in neurologically-intact humans. Although load changed unpredictably from one trial to the next, subjects nevertheless used sensorimotor memories from recent movements to predict and compensate upcoming loads. Prediction enabled subjects to adapt performance so that the task was accomplished with minimum effort. Population analyses of functional images revealed a distributed, bilateral network of cortical and subcortical activity supporting predictive load compensation during visual target capture. Cortical regions – including prefrontal, parietal and hippocampal cortices – exhibited trial-by-trial fluctuations in BOLD signal consistent with the storage and recall of sensorimotor memories or “states” important for spatial working memory. Bilateral activations in associative regions of the striatum demonstrated temporal correlation with the magnitude of kinematic performance error (a signal that could drive reward-optimizing reinforcement learning and the prospective scaling of previously learned motor programs). BOLD signal correlations with load prediction were observed in the cerebellar cortex and red nuclei (consistent with the idea that these structures generate adaptive fusimotor signals facilitating cancelation of expected proprioceptive feedback, as required for conditional feedback adjustments to ongoing motor commands and feedback error learning). Analysis of single subject images revealed that predictive activity was at least as likely to be observed in more than one of these neural systems as in just one. We conclude therefore that motor adaptation is mediated by predictive compensations supported by multiple, distributed, cortical and subcortical structures

    Materials for Advanced Turbine Engines

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    An attempt was made to improve methods for producing powder metallurgy aircraft gas turbine engine parts from the nickel base superalloy known as Rene 95. The parts produced were the high pressure turbine aft shaft for the CF6-50 engine and the stages 5 through 9 compressor disk forgings for the CFM56/F101 engines. A 50% cost reduction was achieved as compared to conventional cast and wrought processing practices. An integrated effort involving several powder producers and a major forging source were included

    Inhibition of RNA polymerase II transcription in human cells by synthetic DNA-binding ligands

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    Sequence-specific DNA-binding small molecules that can permeate human cells potentially could regulate transcription of specific genes. Multiple cellular DNA-binding transcription factors are required by HIV type 1 for RNA synthesis. Two pyrrole-imidazole polyamides were designed to bind DNA sequences immediately adjacent to binding sites for the transcription factors Ets-l, lymphoid-enhancer binding factor 1, and TATA-box binding protein. These synthetic ligands specifically inhibit DNA-binding of each transcription factor and HIV type 1 transcription in cell-free assays. When used in combination, the polyamides inhibit virus replication by >99% in isolated human peripheral blood lymphocytes, with no detectable cell toxicity, The ability of small molecules to target predetermined DNA sequences located within RNA polymerase II promoters suggests a general approach for regulation of gene expression, as well as a mechanism for the inhibition of viral replication

    Effect of Lignin Variation on Biomass Conversion: An analysis of pretreatment methods for poplar samples

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    The conversion of lignocellulosic polysaccharides has been studied as an alternative to petroleum for producing fuels and chemical products, such as those in plastics. However, biomass lignin has been shown to inhibit polysaccharide conversion. Lignin, an organic polymer, surrounds biomass polysaccharides, hemicellulose and cellulose, making the biomass resistant to deconstruction and limiting polysaccharide conversion yields. Increases in polysaccharide conversion yields are seen when using physical or chemical pretreatment methods that increase convertible cellulose, remove lignin, and restructure biomass. A physical pretreatment, liquid hot water (LHW), solubilizes hemicellulose and melts lignin using hot, pressured water. A chemical treatment, sodium-chlorite acetic acid (SCAA), uses a strong oxidizing agent coupled with acid to chemically remove the lignin. This study analyzed LHW and SCAA pretreatments, each at two levels of severity, for aiding in deconstruction of wild type poplar biomass and poplar genetically modified for increased lignin digestibility. Following pretreatments, biomass composition was analyzed via a standard method using a combination of acid hydrolysis deconstruction and biomass fractionation. We report that increasing length of SCAA treatments shows sequential reduction in total lignin (11.8%, 8.0%) when compared to untreated biomass (23.1%) and provides an average 27.3% increase in the portion of total lignin that is acid digestible. LHW pretreatments increase the proportion of available glucan for conversion while minimally changing biomass structure in contrast to the SCAA treatment which largely alters biomass composition. Reported biomass composition changes suggest that pretreatments used with previously studied biomass conversion methods increase polysaccharide conversion yields to value added chemicals

    N2O release from agro-biofuel production negates global warming reduction by replacing fossil fuels

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    The relationship, on a global basis, between the amount of N fixed by chemical, biological or atmospheric processes entering the terrestrial biosphere, and the total emission of nitrous oxide (N<sub>2</sub>O), has been re-examined, using known global atmospheric removal rates and concentration growth of N<sub>2</sub>O as a proxy for overall emissions. For both the pre-industrial period and in recent times, after taking into account the large-scale changes in synthetic N fertiliser production, we find an overall conversion factor of 3&ndash;5% from newly fixed N to N<sub>2</sub>O-N. We assume the same factor to be valid for biofuel production systems. It is covered only in part by the default conversion factor for "direct" emissions from agricultural crop lands (1%) estimated by IPCC (2006), and the default factors for the "indirect" emissions (following volatilization/deposition and leaching/runoff of N: 0.35&ndash;0.45%) cited therein. However, as we show in the paper, when additional emissions included in the IPCC methodology, e.g. those from livestock production, are included, the total may not be inconsistent with that given by our "top-down" method. When the extra N<sub>2</sub>O emission from biofuel production is calculated in "CO<sub>2</sub>-equivalent" global warming terms, and compared with the quasi-cooling effect of "saving" emissions of fossil fuel derived CO<sub>2</sub>, the outcome is that the production of commonly used biofuels, such as biodiesel from rapeseed and bioethanol from corn (maize), depending on N fertilizer uptake efficiency by the plants, can contribute as much or more to global warming by N<sub>2</sub>O emissions than cooling by fossil fuel savings. Crops with less N demand, such as grasses and woody coppice species, have more favourable climate impacts. This analysis only considers the conversion of biomass to biofuel. It does not take into account the use of fossil fuel on the farms and for fertilizer and pesticide production, but it also neglects the production of useful co-products. Both factors partially compensate each other. This needs to be analyzed in a full life cycle assessment

    FLOX/methane pump-fed engine study

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    FLOX and methane rocket propellant for use with modified RL-10-A-1 engin
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