23 research outputs found

    Enhanced Thermal Object Imaging by Photon Addition or Subtraction

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    Long-baseline interferometry (LBI) is used to reconstruct the image of faint thermal objects. The image quality, for a given exposure time, is in general limited by a low signal-to-noise ratio (SNR). We show theoretically that a significant increase of the SNR, in a LBI, is possible by adding or subtracting photons to the thermal beam. At low photon counts, photon addition-subtraction technology strongly enhances the image quality. We have experimentally realized a nondeterministic physical protocol for photon subtraction. Our theoretical predictions are supported by experimental results.Comment: 4 pages, 5 figure

    The effect of the timing of exposure to Campylobacter jejuni on the gut microbiome and inflammatory responses of broiler chickens

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    Background Campylobacters are an unwelcome member of the poultry gut microbiota in terms of food safety. The objective of this study was to compare the microbiota, inflammatory responses, and zootechnical parameters of broiler chickens not exposed to Campylobacter jejuni with those exposed either early at 6 days old or at the age commercial broiler chicken flocks are frequently observed to become colonized at 20 days old. Results Birds infected with Campylobacter at 20 days became cecal colonized within 2 days of exposure, whereas birds infected at 6 days of age did not show complete colonization of the sample cohort until 9 days post-infection. All birds sampled thereafter were colonized until the end of the study at 35 days (mean 6.1 log10 CFU per g of cecal contents). The cecal microbiota of birds infected with Campylobacter were significantly different to age-matched non-infected controls at 2 days post-infection but generally the composition of the cecal microbiota were more affected by bird age as the time post infection increased. The effects of Campylobacter colonization on the cecal microbiota were associated with reductions in the relative abundance of OTUs within the taxonomic family Lactobacillaceae and the Clostridium cluster XIVa. Specific members of the Lachnospiraceae and Ruminococcaceae families exhibit transient shifts in microbial community populations dependent upon the age at which the birds become colonized by C. jejuni. Analysis of ileal and cecal chemokine/cytokine gene expression revealed increases in IL-6, IL-17A and Il-17F consistent with a Th17 response but the persistence of the response was dependent on the stage/time of C. jejuni colonization that coincide with significant reductions in the abundance of Clostridium cluster XIVa. Conclusions This study combines microbiome data, cytokine/chemokine gene expression with intestinal villus and crypt measurements to compare chickens colonized early or late in the rearing cycle to provide insights into the process and outcomes of Campylobacter colonization. Early colonization results in a transient growth rate reduction and pro-inflammatory response but persistent modification of the cecal microbiota. Late colonization produces pro-inflammatory responses with changes in the cecal microbiota that will endure in market ready chickens

    The Covid-19 Pandemic and the Accommodation Sharing Sector: Effects and Prospects for Recovery

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    The Covid-19 pandemic has spread like wildfire across the globe. The hospitality industry, including the accommodation sharing sector, has been one of the hardest hit. Renting an Airbnb property, sharing a room via Couchsurfing and exchanging homes via LoveHomeSwap became almost impossible under the new restrictions. This paper analyses the effects of the Covid-19 crisis on the accommodation sharing sector and conceptually uncovers the underlying reasons for its disruption. We submit that the main strengths of the accommodation sharing sector, which originally drove its rise, became its weaknesses during the pandemic. An asset-light business model, the intermediation of physical transactions via online platforms, a reliance on individually owned and underused properties, and the popularization of access over ownership propelled the initial expansion of this sector. However, these all backfired during the pandemic. The paper outlines potential avenues for the post-pandemic recovery of accommodation sharing and presents future directions for research

    Entry of Providers onto a Sharing Economy Platform: Macro-level Factors and Social Interaction

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    ORCID iD: Oksana Gerwe https://orcid.org/0000-0001-8814-7485.The author(s) received no financial support for the research, authorship, and/or publication of this article
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