339 research outputs found

    Climate Change Adaptation Case Study: Benefit-Cost Analysis of Coastal Flooding Hazard Mitigation

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    The damage Hurricane Sandy caused had far-reaching repercussions up and down the East Coast of the United States. Vast coastal flooding accompanied the storm, inundating homes, businesses, and utility and emergency facilities. Since the storm, projects to mitigate similar future floods have been scrutinized. Such projects not only need to keep out floodwaters but also be designed to withstand the effect that climate change might have on rising sea levels and increased flood risk. In this study, we develop an economic model to assess the costs and benefits of a berm (sea wall) to mitigate the effects of flooding from a large storm. We account for the lifecycle costs of the project, which include those for the upfront construction of the berm, ongoing maintenance, land acquisition, and wetland and recreation zone construction. Benefits of the project include avoided fatalities, avoided residential and commercial damages, avoided utility and municipal damages, recreational and health benefits, avoided debris removal expenses, and avoided loss of function of key transportation and commercial infrastructure located in the area. Our estimate of the beneficial effects of the berm includes ecosystem services from wetlands and health benefits to the surrounding community from a park and nature system constructed along the berm. To account for the effects of climate change and verify that the project will maintain its effectiveness over the long term, we allow the risk of flooding to increase over time. Over our 50-year time horizon, we double the risk of 100- and 500-year flood events to account for the effects of sea level rise on coastal flooding. Based on the economic analysis, the project is highly cost beneficial over its 50-year timeframe. This analysis demonstrates that climate change adaptation investments can be cost beneficial even though they mitigate the impacts of low-probability, high-consequence events

    Detecting Molecular Rotational Dynamics Complementing the Low-Frequency Terahertz Vibrations in a Zirconium-Based Metal-Organic Framework

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    We show clear experimental evidence of co-operative terahertz (THz) dynamics observed below 3 THz (~100 cm-1), for a low-symmetry Zr-based metal-organic framework (MOF) structure, termed MIL-140A [ZrO(O2C-C6H4-CO2)]. Utilizing a combination of high-resolution inelastic neutron scattering and synchrotron radiation far-infrared spectroscopy, we measured low-energy vibrations originating from the hindered rotations of organic linkers, whose energy barriers and detailed dynamics have been elucidated via ab initio density functional theory (DFT) calculations. For completeness, we obtained Raman spectra and characterized the alterations to the complex pore architecture caused by the THz rotations. We discovered an array of soft modes with trampoline-like motions, which could potentially be the source of anomalous mechanical phenomena, such as negative linear compressibility and negative thermal expansion. Our results also demonstrate coordinated shear dynamics (~2.5 THz), a mechanism which we have shown to destabilize MOF crystals, in the exact crystallographic direction of the minimum shear modulus (Gmin).Comment: 10 pages, 6 figure

    BOUND OBJECT HIERARCHY SERVICE

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    Presented herein is a hierarchical representation of uniquely identified objects within the physical world, referred to as a “Bound Object Hierarchy Service.” The Bound Object Hierarchy Service enables the synchronous shared view and creation of digital twins among coordinating entities. The system enables the representation and policy based access to objects, mapped from the physical world, that would typically be considered to follow a “bound within” hierarchy. The digital custody and ownership of the physical objects can autonomously change over time within the system (e.g., as an object passes along a supply chain, determined via sensors within the environment and policy based access). The policy based approach can additionally enable third parties or a limited set of the system participants to access the object hierarchy data in order to view specific elements of the tracked objects, along with the sharing of object sensor data

    Feldexperiment zur Wirksamkeit von konkretem vs. abstraktem Eco-Driving Feedback

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    Eco-Driving Feedback Informationssysteme haben das Potenzial, auf sehr rasche und effiziente Weise zur Reduktion von Spritverbrauch und CO2 im Strassentransportwesen beizutragen. Vor allem neuere vernetzte Fahrzeuge bieten durch die zunehmende Digitalisierung der Cockpits viel Freiraum zur Gestaltung und Untersuchung von Eco-Driving Feedback. Neben klassischen „Spritverbrauchs-Tachos findet man heutzutage auch eher abstrakte Formen der Informationsdarbietung, z.B. animierte Pflanzen, die in AbhĂ€ngigkeit vom Spritverbrauch wachsen oder schrumpfen. Diese Möglichkeiten werfen wichtige Fragen auf: Welche Art der Informationsdarbietung Ă€ndert das Fahrverhalten kurzfristig und langfristig effektiver? Welche Fahrverhaltensweisen (z.B. Bremsverhalten) werden in welchem Masse beeinflusst? HĂ€ngen eventuelle Effekte von bestimmten Moderatoren ab? Um diese Fragen zu untersuchen, wurde ein Eco-Driving Feedback System entwickelt, welches den Spritverbrauch des Fahrzeugs auf klassisch „konkrete Art einerseits und auf eher abstrakte Art andererseits anzeigt. Die Auswirkungen auf Fahrverhalten und Spritverbrauch sollen in einem Feldexperiment unter Alltagsbedingungen mit 72 Pannenservice-Fahrern untersucht werden

    Mapping Obscured Star Formation in the Host Galaxy of FRB 20201124A

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    We present high-resolution 1.5--6 GHz Karl G. Jansky Very Large Array (VLA) and Hubble Space Telescope\textit{Hubble Space Telescope} (HST\textit{HST}) optical and infrared observations of the extremely active repeating fast radio burst (FRB) FRB \,20201124A and its barred spiral host galaxy. We constrain the location and morphology of star formation in the host and search for a persistent radio source (PRS) coincident with FRB \,20201124A. We resolve the morphology of the radio emission across all frequency bands and measure a star formation rate SFR ≈8.9 M⊙\approx 8.9\,M_{\odot} yr−1^{-1}, a factor of ≈4−6\approx 4-6 larger than optically-inferred SFRs, demonstrating dust-obscured star formation throughout the host. Compared to a sample of all known FRB hosts with radio emission, the host of FRB \,20201124A has the most significant obscured star formation. While HST{\it HST} observations show the FRB to be offset from the bar or spiral arms, the radio emission extends to the FRB location. We propose that the FRB progenitor could have formed in situ\textit{in situ} (e.g., a magnetar central engine born from the explosion of a massive star). It is still plausible, although less likely, that the progenitor of FRB \,20201124A migrated from the central bar of the host, e.g., via a runaway massive star. We further place a limit on the luminosity of a putative PRS at the FRB position of $L_{\rm 6.0 \ GHz} \lesssim2.6 2.6 \times 10^{27}ergs erg s^{-1}Hz Hz^{-1},twoordersofmagnitudebelowanyPRSknowntodate.However,thislimitisstillbroadlyconsistentwithbothmagnetarnebulaeandhypernebulaemodelsassumingaconstantenergyinjectionrateofthemagnetarandanageof, two orders of magnitude below any PRS known to date. However, this limit is still broadly consistent with both magnetar nebulae and hypernebulae models assuming a constant energy injection rate of the magnetar and an age of \gtrsim 10^{5}$ yr in each model, respectively.Comment: 21 pages, 6 figures, 3 tables, Submitte

    Domestication of Campylobacter jejuni NCTC 11168

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    Reference and type strains of well-known bacteria have been a cornerstone of microbiology research for decades. The sharing of well-characterized isolates among laboratories has run in parallel with research efforts and enhanced the reproducibility of experiments, leading to a wealth of knowledge about trait variation in different species and the underlying genetics. Campylobacter jejuni strain NCTC 11168, deposited at the National Collection of Type Cultures in 1977, has been adopted widely as a reference strain by researchers worldwide and was the first Campylobacter for which the complete genome was published (in 2000). In this study, we collected 23 C . jejuni NCTC 11168 reference isolates from laboratories across the UK and compared variation in simple laboratory phenotypes with genetic variation in sequenced genomes. Putatively identical isolates, identified previously to have aberrant phenotypes, varied by up to 281 SNPs (in 15 genes) compared to the most recent reference strain. Isolates also display considerable phenotype variation in motility, morphology, growth at 37 °C, invasion of chicken and human cell lines, and susceptibility to ampicillin. This study provides evidence of ongoing evolutionary change among C. jejuni isolates as they are cultured in different laboratories and highlights the need for careful consideration of genetic variation within laboratory reference strains. This article contains data hosted by Microreact
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