1,605 research outputs found

    Utilizing Computer Vision for Automated Cellular Microscopy

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    Abstract. Post-acquisition data analysis of microscopy images is a vital yet time-consuming process for researchers. Quantitative fields such as biology and microbiology often require using images as primary data sources. Finding methods to automate this process would increase the throughput, quality, and reproducibility. This research aims to provide a novel end-to-end pipeline that reduces the workload on researchers in identifying cell cytoplasm and nuclei while creating a process that can scale to the researcher\u27s needs. The proposed methodology utilizes various image-processing techniques to rapidly identify the boundaries of cells and nuclei, including filtering, thresholding, and deep learning. The results of this research indicate that the proposed methodology could be a valuable tool for microbiologists, saving time and effort for accurate data collection

    2-Stroke Engine Options for Automotive Use::A Fundamental Comparison of Different Potential Scavenging Arrangements for Medium-Duty Truck Applications

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    The work presented here seeks to compare different means of providing scavenging systems for an automotive 2-stroke engine. It follows on from previous work solely investigating uniflow scavenging systems, and aims to provide context for the results discovered there as well as to assess the benefits of a new scavenging system: the reverse-uniflow sleeve-valve. For the study the general performance of the engine was taken to be suitable to power a medium-duty truck, and all of the concepts discussed here were compared in terms of indicated fuel consumption for the same cylinder swept volume using a one-dimensional engine simulation package. In order to investigate the sleeve-valve designs layout drawings and analysis of the Rolls-Royce Crecy-type sleeve had to be undertaken. A new methodology for optimization was developed and the analysis process also took into account work done by the charging system, this being assumed to be a combination of supercharger and turbocharger to permit some exhaust waste heat recovery. As a result of this work it was found that the opposed-piston configuration provides the best attributes since it allows maximum expansion and minimum heat transfer. It gave net specific fuel consumption results which were 9.6% lower than the loop-scavenged engine (which was marginally the worst of the configurations investigated). The other uniflow systems were next, with the reverse sleeve valve being the most promising (3.4% better than the loop-scavenged engine). Furthermore, although the general performance of the loop-scavenged configuration was closer to the other designs than was initially expected, it was found to be compromised by its requirement to have intake and exhaust ports at the same height in the cylinder, thus lengthening the gas exchange events for any given angle-area and consequently reducing the effective (or trapped) compression and expansion ratios. This was despite the use of a charge trapping valve to provide asymmetric port timing and minimize charge short-circuiting, the adoption of which was felt to be a factor in its better-than-expected performance. Finally, the reverse-loop-scavenged poppet-valve type was found to be so compromised by breathing and valve train kinematics that it was not taken to a full optimization. For the opposed-piston engine, once the port timing obtained by the optimizer had been established, a supplementary study was conducted looking at the effect of relative phasing of the crankshafts on performance and economy. This was found to have a small effect on fuel consumption for a significant change in compression ratio, suggesting that, if available, variable crankshaft phasing could be a very important control actuator for gasoline compression ignition in such an engine. Importantly, it was found that existing experiential guidelines for port angle-area specification for loop-scavenged, piston-ported engines using crankcase compression could also be applied to all of the other scavenging types, this having been done here in order to provide a starting point for the work. This important result has not been demonstrated before for such a wide range of architectures. The optimizer employed then allowed further improvements to be made over the starting point. The paper therefore presents a fundamental comparison of scavenging systems using a new approach, providing insights and information which have not been shown before.</p

    Ariel - Volume 6 Number 4

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    Editors Mark Dembert J.D. Kanofsky Frank Chervenak John Lammie Curt Cummings Entertainment Robert Breckenridge Joe Conti Gary Kaskey Photographer Larry Glazerman Overseas Editor Mike Sinason Humorist Jim McCann Staff Ken Jaffe Bob Sklaroff Halley Faust Jim Burk

    Ozone depletion, greenhouse gases, and climate change

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    This symposium was organized to study the unusual convergence of a number of observations, both short and long term that defy an integrated explanation. Of particular importance are surface temperature observations and observations of upper atmospheric temperatures, which have declined significantly in parts of the stratosphere. There has also been a dramatic decline in ozone concentration over Antarctica that was not predicted. Significant changes in precipitation that seem to be latitude dependent have occurred. There has been a threefold increase in methane in the last 100 years; this is a problem because a source does not appear to exist for methane of the right isotopic composition to explain the increase. These and other meteorological global climate changes are examined in detail

    Ariel - Volume 6 Number 4 (Alternate Version)

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    Editors Mark Dembert J.D. Kanofsky Frank Chervenak John Lammie Curt Cummings Entertainment Robert Breckenridge Joe Conti Gary Kaskey Photographer Larry Glazerman Overseas Editor Mike Sinason Humorist Jim McCann Staff Kenn Jaffe Bob Sklaroff Halley Faust Jim Burke Jay Amsterdam Morton A. Klein Nancy Redfer

    A prescription for the Epley maneuver: www.youtube.com?

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    OBJECTIVES: Video-sharing Web sites are being used for information about common conditions including dizziness. The Epley maneuver (EM) is a simple and effective treatment for benign paroxysmal positional vertigo (BPPV) of the posterior canal. However, the maneuver is underused in routine care. In this study, we aimed to describe and analyze the available information about the EM on youtube.com. METHODS: A YouTube search was performed on August 31, 2011, for videos that demonstrated the entire EM. Detailed data were abstracted from each video and corresponding Web site. Videos were rated on the accuracy of the maneuver by 2 authors, with differences resolved by adjudication. Comments posted by viewers were assessed for themes regarding video use. RESULTS: Of the 3,319 videos identified, 33 demonstrated the EM. The total number of hits for all videos was 2,755,607. The video with the most hits (802,471) was produced by the American Academy of Neurology. Five of the videos accounted for 85% of all the hits. The maneuver demonstration was rated as accurate in 64% (21) of the videos. Themes derived from the 424 posted comments included patients self-treating with the maneuver after reviewing the videos, and providers using the videos as a prescribed treatment or for educational purposes. CONCLUSION: Accurate video demonstration of the Epley maneuver is available and widely viewed on YouTube. Video-sharing media may be an important way to disseminate effective interventions such as the EM. The impact of video Web sites on outcomes and costs of care is not known and warrants future study

    Neighbor-directed histidine N (Ï„)-alkylation: A route to imidazolium-containing phosphopeptide macrocycles

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    Our recently discovered, selective, on-resin route to N(Ï„)-alkylated imidazolium-containing histidine residues affords new strategies for peptide mimetic design. In this, we demonstrate the use of this chemistry to prepare a series of macrocyclic phosphopeptides, in which imidazolium groups serve as ring-forming junctions. Interestingly, these cationic moieties subsequently serve to charge-mask the phosphoamino acid group that directed their formation. Neighbor-directed histidine N(Ï„)-alkylation opens the door to new families of phosphopeptidomimetics for use in a range of chemical biology contexts.National Institutes of Health (U.S.) (Grants ES015339 and GM104047

    Submersible Generator for Marine Hydrokinetics

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    A submersible generator was designed as a distinct and critical subassembly of marine hydrokinetics systems, specifically tidal and stream energy conversion. The generator is designed to work with both vertical and horizontal axis turbines. The final product is a high-pole-count, radial-flux, permanent magnet, rim mounted generator, initially rated at twenty kilowatts in a two-meter-per-second flow, and designed to leverage established and simple manufacturing processes. The generator was designed to work with a 3 meter by 7 meter Gorlov Helical Turbine or a marine hydrokinetic version of the FloDesign wind turbine. The team consisted of experienced motor/generator design engineers with cooperation from major US component suppliers (magnetics, coil winding and electrical steel laminations). Support for this effort was provided by Lucid Energy Technologies and FloDesign, Inc. The following tasks were completed: ⢠Identified the conditions and requirements for MHK generators. ⢠Defined a methodology for sizing and rating MHK systems. ⢠Selected an MHK generator topology and form factor. ⢠Completed electromechanical design of submersible generator capable of coupling to multiple turbine styles. ⢠Investigated MHK generator manufacturing requirements. ⢠Reviewed cost implications and financial viability. ⢠Completed final reporting and deliverable
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