3,105 research outputs found

    All That Sprawl, Y’all: An Analysis of Development on Steinwehr Avenue and York Street in Gettysburg, Pennsylvania, from 1971 to 2014

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    The advent of the automobile transformed the American landscape in the 20th century. In conjunction with the increasing importance of the automobile, numerous post-WW II government programs such as the Interstate Highway System encouraged suburban sprawl. Towns and cities adjacent to tourist attractions, known as gateway communities, face unique problems caused by sprawl. Gettysburg, Pennsylvania, is an example of a gateway community as it includes the Gettysburg National Military Park. Two study sites, portions of Steinwehr Avenue and York Street, were studied to analyze the effects of sprawl in Gettysburg. The sites were analyzed using ArcGIS, data compiled from historic phonebooks, and discussions with local business owners. Development along York Street exemplifies an auto-centric culture with many regional and national chain establishments set back from the road. Steinwehr Avenue represents a walkable community comprising on-street parking, sidewalks, and local “mom-and-pop” establishments. Trends associated with categories of businesses varied between the two sites and revealed different development patterns. We predict that that York Street will continue to sprawl while Steinwehr Avenue development will be limited due to its close proximity to the battlefield

    Bosnia Pain (SOB!)

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    BOSNIA, GA. REV., ENDED. NEVER AGAIN! (SOB!) a Southern minister, learning it\u27s all over, vows it won\u27t repeat

    Large scale flow around turbulent spots

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    Numerical simulations of a model of plane Couette flow focusing on its in-plane spatio-temporal properties are used to study the dynamics of turbulent spots.Comment: 16 pages, 6 figure

    Displacement effect in strong-field atomic ionization by an XUV pulse

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    We study strong-field atomic ionization driven by an XUV pulse with a non\-zero displacement, the quantity defined as the integral of the pulse vector potential taken over the pulse duration. We demonstrate that the use of such pulses may lead to an extreme sensitivity of the ionization process to subtle changes of the parameters of a driving XUV pulse, in particular, the ramp-on/off profile and the carrier envelope phase. We illustrate this sensitivity for atomic hydrogen and lithium driven by few-femto\-second XUV pulses with intensity in the 1014 W/cm2\rm 10^{14}~W/cm^2 range. We argue that the observed effect is general and should modify strong-field ionization of any atom, provided the ionization rate is sufficiently high.Comment: 5 pages, 7 figure

    Fluorescence Blinking Statistics From CdSe Core And Core/Shell Nanorods

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    We report fluorescence blinking statistics measured from single CdSe nanorods (NRs) of seven different sizes with aspect ratios ranging from 3 to 11. This study also included core/shell CdSe/ZnSe NRs and core NRs with two different surface ligands producing different degrees of surface passivation. We compare the findings for NRs to our measurements of blinking statistics from spherical CdSe core and CdSe/ZnS core/shell nanocrystals (NCs). We find that, for both NRs and spherical NCs, the off-time probability distributions are well described by a power law, while the on-time probability distributions are best described by a truncated power law, P(tau(on)) similar to tau(-alpha)(on)e(on)(-tau)(/tau c). The measured crossover time, tau(c), is indistinguishable within experimental uncertainty for core and core/shell NRs, as well as for core NRs with different ligands, for the same core size, indicating that surface passivation does not affect the blinking statistics significantly. We find that, at fixed excitation intensity, 1/tau(c) increases approximately linearly with increasing NR aspect ratio; for a given sample, 1/tau(c) increases very gradually with increasing excitation intensity. Examining 1/tau(c) versus the single-particle photon absorption rate for all samples indicates that the change in NR absorption cross section with sample size can account for some but not all of the differences in crossover time. This suggests that the degree of quantum confinement may be partially responsible for the aspect ratio dependence of the crossover time

    Bridging Innate and Adaptive Antitumor Immunity Targeting Glycans

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    Effective immunotherapy for cancer depends on cellular responses to tumor antigens. The role of major histocompatibility complex (MHC) in T-cell recognition and T-cell receptor repertoire selection has become a central tenet in immunology. Structurally, this does not contradict earlier findings that T-cells can differentiate between small hapten structures like simple glycans. Understanding T-cell recognition of antigens as defined genetically by MHC and combinatorially by T cell receptors led to the “altered self” hypothesis. This notion reflects a more fundamental principle underlying immune surveillance and integrating evolutionarily and mechanistically diverse elements of the immune system. Danger associated molecular patterns, including those generated by glycan remodeling, represent an instance of altered self. A prominent example is the modification of the tumor-associated antigen MUC1. Similar examples emphasize glycan reactivity patterns of antigen receptors as a phenomenon bridging innate and adaptive but also humoral and cellular immunity and providing templates for immunotherapies

    Towards Guidelines for Assessing Qualities of Machine Learning Systems

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    Nowadays, systems containing components based on machine learning (ML) methods are becoming more widespread. In order to ensure the intended behavior of a software system, there are standards that define necessary quality aspects of the system and its components (such as ISO/IEC 25010). Due to the different nature of ML, we have to adjust quality aspects or add additional ones (such as trustworthiness) and be very precise about which aspect is really relevant for which object of interest (such as completeness of training data), and how to objectively assess adherence to quality requirements. In this article, we present the construction of a quality model (i.e., evaluation objects, quality aspects, and metrics) for an ML system based on an industrial use case. This quality model enables practitioners to specify and assess quality requirements for such kinds of ML systems objectively. In the future, we want to learn how the term quality differs between different types of ML systems and come up with general guidelines for specifying and assessing qualities of ML systems.Comment: Has been accepted at the 13th International Conference on the Quality of Information and Communications Technology QUATIC2020 (https://2020.quatic.org/). QUATIC 2020 proceedings will be included in a volume of Springer CCIS Series (Communications in Computer and Information Science
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