1,419 research outputs found

    Analyzing the Economics Values of An Alternative Preprocessing Facility in the Biomass Feedstocks - Biorefinery Supply Chain

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    It is generally believed that preprocessing procedure can reduce the transportation and storage costs of biomass feedstock for biofuel production by condensing the feedstock’s size. However, the capital costs of preprocessing facilities could be significant in the feedstock logistics system. Applying a GIS and mixed-integer mathematical programming model, this study evaluates the economic values of a preprocessing technology, stretch‐wrap baling, in the biomass feedstock supply chain for a potential commercial-scale switchgrass biorefinery in East Tennessee. Preliminary results suggest that the stretch-wrap baling equipment outperforms the conventional hay harvest methods in terms of total delivered costs. Although the densification process involves additional capital and operation costs, the total delivered costs of switchgrass for a 25- million-gallon per year biorefinery in the preprocessing system is 12% − 21% lower than various logistic methods using conventional hay equipments.Biomass feedstock, cellulosic biofuel, logistic costs, preprocessing technology, Crop Production/Industries, Resource /Energy Economics and Policy, Q16, D24,

    The Zebrafish Homologue of the Human DYT1 Dystonia Gene Is Widely Expressed in CNS Neurons but Non-Essential for Early Motor System Development

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    DYT1 dystonia is caused by mutation of the TOR1A gene, resulting in the loss of a single glutamic acid residue near the carboxyl terminal of TorsinA. The neuronal functions perturbed by TorsinA[ΔE] are a major unresolved issue in understanding the pathophysiology of dystonia, presenting a critical roadblock to developing effective treatments. We identified and characterized the zebrafish homologue of TOR1A, as a first step towards elucidating the functions of TorsinA in neurons, in vivo, using the genetically-manipulable zebrafish model. The zebrafish genome was found to contain a single alternatively-spliced tor1 gene, derived from a common ancestral locus shared with the dual TOR1A and TOR1B paralogues found in tertrapods. tor1 was expressed ubiquitously during early embryonic development and in multiple adult tissues, including the CNS. The 2.1 kb tor1 mRNA encodes Torsin1, which is 59% identical and 78% homologous to human TorsinA. Torsin1 was expressed as major 45 kDa and minor 47 kDa glycoproteins, within the cytoplasm of neurons and neuropil throughout the CNS. Similar to previous findings relating to human TorsinA, mutations of the ATP hydrolysis domain of Torsin1 resulted in relocalization of the protein in cultured cells from the endoplasmic reticulum to the nuclear envelope. Zebrafish embryos lacking tor1 during early development did not show impaired viability, overt morphological abnormalities, alterations in motor behavior, or developmental defects in the dopaminergic system. Torsin1 is thus non-essential for early development of the motor system, suggesting that important CNS functions may occur later in development, consistent with the critical time window in late childhood when dystonia symptoms usually emerge in DYT1 patients. The similarities between Torsin1 and human TorsinA in domain organization, expression pattern, and cellular localization suggest that the zebrafish will provide a useful model to understand the neuronal functions of Torsins in vivo

    Licensed control does not reduce local Cormorant Phalacrocorax carbo population size in winter

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    Cormorants Phalacrocorax carbo have increased on European freshwaters, creating conflicts with fishing interests. As a result, control measures have been implemented in several countries, although their effect on the English population has yet to be determined. Wetland Bird Survey data was used to derive population growth rates (PGR) of non-coastal Cormorant populations in England. PGR was analysed in relation to control intensity at different scales (5- to 30-km radius) from 2001 to 2009 in order to determine (1) the extent to which control intensity (proportion of the local population shot per winter) was associated with site-level population change, and (2) whether potential effects of control intensity were evident on Special Protection Areas (SPAs). There were no clear differences in PGR when comparing sites which had experienced control versus sites where control had never been carried out. The few significant relationships between control intensity and Cormorant PGR detected were mostly positive, i.e. population growth was associated with higher control intensity. Control intensity was not related to Cormorant numbers in SPAs. Positive associations with control may arise because control is reactive, or because non-lethal effects cause greater dispersal of Cormorants. These results provide no evidence that Cormorant removal at local scales is having an effect on longer term (i.e. year-to-year) population size at a site level. They also suggest that control measures have not affected national population trends, although a better understanding of site use and movements of individual Cormorants needs to be developed at smaller scales (including those due to disturbance caused by control measures) to more fully understand processes at larger scales. Further research is also needed into the extent to which lethal and non-lethal effects of control on Cormorants are having the desired impact on predation rates of fish, and so help resolve the conflict between Cormorants and fisheries.</p

    Dedicated Energy Crop Supply Chain and Associated Feedstock Transportation Emissions: A Case Study of Tennessee

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    and Bradly Wilson This study minimizes total cost for single-feedstock supply chains of two dedicated energy crops, perennial switchgrass and biomass sorghum, in Tennessee using a spatial optimization model. Greenhouse gas emissions from the transport of feedstock to the conversion facility were estimated for respective feedstock supply chains. Results show that different demand for land types from two feedstocks and the geographically diverse landscape across the state affect the economics of bioenergy crops supply chains and feedstock transportation emissions. Switchgrass is more suitable than biomass sorghum for biofuel production in Tennessee based on the supply chains cost and feedstock hauling emissions

    Space and transatmospheric propulsion technology

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    This report focuses primarily on Japan's programs in liquid rocket propulsion and propulsion for spaceplane and related transatmospheric areas. It refers briefly to Japan's solid rocket programs and to new supersonic air-breathing propulsion efforts. The panel observed that the Japanese had a carefully thought-out plan, a broad-based program, and an ambitious but achievable schedule for propulsion activity. Japan's overall propulsion program is behind that of the United States at the time of this study, but the Japanese are gaining rapidly. The Japanese are at the forefront in such key areas as advanced materials, enjoying a high level of project continuity and funding. Japan's space program has been evolutionary in nature, while the U.S. program has emphasized revolutionary advances. Projects have typically been smaller in Japan than in the United States, focusing on incremental advances in technology, with an excellent record of applying proven technology to new projects. This evolutionary approach, coupled with an ability to take technology off the shelf from other countries, has resulted in relatively low development costs, rapid progress, and enhanced reliability. Clearly Japan is positioned to be a world leader in space and transatmospheric propulsion technology by the year 2000

    Joint analysis of stressors and ecosystem services to enhance restoration effectiveness

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    With increasing pressure placed on natural systems by growing human populations, both scientists and resource managers need a better understanding of the relationships between cumulative stress from human activities and valued ecosystem services. Societies often seek to mitigate threats to these services through large-scale, costly restoration projects, such as the over one billion dollar Great Lakes Restoration Initiative currently underway. To help inform these efforts, we merged high-resolution spatial analyses of environmental stressors with mapping of ecosystem services for all five Great Lakes. Cumulative ecosystem stress is highest in near-shore habitats, but also extends offshore in Lakes Erie, Ontario, and Michigan. Variation in cumulative stress is driven largely by spatial concordance among multiple stressors, indicating the importance of considering all stressors when planning restoration activities. In addition, highly stressed areas reflect numerous different combinations of stressors rather than a single suite of problems, suggesting that a detailed understanding of the stressors needing alleviation could improve restoration planning. We also find that many important areas for fisheries and recreation are subject to high stress, indicating that ecosystem degradation could be threatening key services. Current restoration efforts have targeted high-stress sites almost exclusively, but generally without knowledge of the full range of stressors affecting these locations or differences among sites in service provisioning. Our results demonstrate that joint spatial analysis of stressors and ecosystem services can provide a critical foundation for maximizing social and ecological benefits from restoration investments. www.pnas.org/lookup/suppl/doi:10.1073/pnas.1213841110/-/DCSupplementa

    NASA Goddard Space Flight Center's Compendium of Recent Total Ionizing Dose and Displacement Damage Dose Results

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    Total ionizing dose and displacement damage dose testing were performed to characterize and determine the suitability of candidate electronics for NASA spacecraft and program use

    Single-Cell Redox Imaging Demonstrates a Distinctive Response of Dopaminergic Neurons to Oxidative Insults

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    Producción CientíficaAims: The study of the intracellular oxido-reductive (redox) state is of extreme relevance to the dopamine (DA) neurons of the substantia nigra pars compacta. These cells possess a distinct physiology intrinsically associated with elevated reactive oxygen species production, and they selectively degenerate in Parkinson's disease under oxidative stress conditions. To test the hypothesis that these cells display a unique redox response to mild, physiologically relevant oxidative insults when compared with other neuronal populations, we sought to develop a novel method for quantitatively assessing mild variations in intracellular redox state. Results: We have developed a new imaging strategy to study redox variations in single cells, which is sensitive enough to detect changes within the physiological range. We studied DA neurons' physiological redox response in biological systems of increasing complexity--from primary cultures to zebrafish larvae, to mammalian brains-and identified a redox response that is distinctive for substantia nigra pars compacta DA neurons. We studied simultaneously, and in the same cells, redox state and signaling activation and found that these phenomena are synchronized. Innovation: The redox histochemistry method we have developed allows for sensitive quantification of intracellular redox state in situ. As this method is compatible with traditional immunohistochemical techniques, it can be applied to diverse settings to investigate, in theory, any cell type of interest. Conclusion: Although the technique we have developed is of general interest, these findings provide insights into the biology of DA neurons in health and disease and may have implications for therapeutic intervention

    Queues, Crowds, and Angry Mobs: Face Identification Under Distraction in a Virtual Airport

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    In visual environments, selective attention must be employed to focus on task-relevant stimuli. A key question here concerns the extent to which other stimuli within the visual field influence target processing. In this study we ask whether face identity matching is subject to similar effects from irrelevant stimuli in the visual field, specifically task-irrelevant people. While most previous studies rely on highly controlled face and body stimuli presented in isolation, here we use a more realistic environment. Participants take the role of passport officers and must match a person’s face to their photo-ID while other people appear in the background, waiting to be processed. Presenting an interactive virtual environment on screen (Experiment 1 and 2) or in immersive VR (Experiment 3), we generally found no evidence for distraction from background people on face-matching accuracy. However, when immersed in VR, an angry crowd in the background increased matching speed, while not affecting accuracy. We discuss the theoretical implications of these results and their potential importance in practical settings
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