1,017 research outputs found

    Social determinants of content selection in the age of (mis)information

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    Despite the enthusiastic rhetoric about the so called \emph{collective intelligence}, conspiracy theories -- e.g. global warming induced by chemtrails or the link between vaccines and autism -- find on the Web a natural medium for their dissemination. Users preferentially consume information according to their system of beliefs and the strife within users of opposite narratives may result in heated debates. In this work we provide a genuine example of information consumption from a sample of 1.2 million of Facebook Italian users. We show by means of a thorough quantitative analysis that information supporting different worldviews -- i.e. scientific and conspiracist news -- are consumed in a comparable way by their respective users. Moreover, we measure the effect of the exposure to 4709 evidently false information (satirical version of conspiracy theses) and to 4502 debunking memes (information aiming at contrasting unsubstantiated rumors) of the most polarized users of conspiracy claims. We find that either contrasting or teasing consumers of conspiracy narratives increases their probability to interact again with unsubstantiated rumors.Comment: misinformation, collective narratives, crowd dynamics, information spreadin

    Decoupled Lithospheric Folding, Lower Crustal Flow Channels, and the Growth of Tibetan Plateau

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    The growth mechanism of the Tibetan Plateau, postulated by a number of hypotheses, remains under intense debate. Our analysis of recent satellite-based gravity model reveals that Tibetan lithosphere has been decoupled and folded. It is further evidenced by the existence of crustal melts and channel flow that have been observed by seismic and magnetotelluric explorations. Based on 3D geodynamic simulations, we elucidate the exact buckling structures in the upper crust and lithospheric mantle: at mixed wavelengths between ∼240 and ∼400 km, the lower crustal viscosity is smaller than ∼10 19 Pa·s, implicating weak lower crustal flow beneath the Plateau. This mixed wavelength is consistent with the result of our inverse gravity modeling. Our results facilitate a new plausible hypothesis that the decoupled lithospheric folding mechanism can explain the growth mechanism of the anomalously thick and wide Tibetan Plateau by conflating our idea and contemporary hypothesized scientific findings

    Ethane steam reforming over a platinum/alumina catalyst: effect of sulphur poisoning

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    In this study we have examined the adsorption of hydrogen sulfide and methanethiol over platinum catalysts and examined the effect of these poisons on the steam reforming of ethane. Adsorption of hydrogen sulfide was measured at 293 and 873 K. At 873 K the adsorbed state of hydrogen sulfide in the presence of hydrogen was SH rather than S, even though the Pt:S ratio was unity. The effect of 11.2 ppm hydrogen sulfide or methanethiol on the steam reforming of ethane was studied at 873 K and 20 barg. Both poisons deactivated the catalyst over a number of hours, but methanethiol was found to be more deleterious, reducing the conversion by almost an order of magnitude, possibly due to the co-deposition of sulfur and carbon. Changes in the selectivity revealed that the effect of sulfur was not uniform on the reactions occurring, with the production of methane reduced proportionally more than the other products, due to the surface sensitivity of the hydrogenolysis and methanation reactions. The water-gas shift reaction was affected to a lesser extent. No regeneration was observed when hydrogen sulfide was removed from the feedstream in agreement with adsorption studies. A slight regeneration was observed when methanethiol was removed from the feed, but this was believed to be due to the removal of carbon rather than sulfur. The overall effect of sulfur poisoning was to reduce activity and enhance hydrogen selectivity

    Survey propagation at finite temperature: application to a Sourlas code as a toy model

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    In this paper we investigate a finite temperature generalization of survey propagation, by applying it to the problem of finite temperature decoding of a biased finite connectivity Sourlas code for temperatures lower than the Nishimori temperature. We observe that the result is a shift of the location of the dynamical critical channel noise to larger values than the corresponding dynamical transition for belief propagation, as suggested recently by Migliorini and Saad for LDPC codes. We show how the finite temperature 1-RSB SP gives accurate results in the regime where competing approaches fail to converge or fail to recover the retrieval state

    The Selective Personalized Radio-Immunotherapy for Locally Advanced NSCLC Trial (SPRINT)

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    Purpose/Objective(s): Standard therapy for unresectable locally advanced non-small cell lung cancer (LA-NSCLC) is concurrent chemoradiotherapy (chemoRT), which is usually followed by adjuvant durvalumab. We performed a prospective trial testing sequential pembrolizumab and risk-adapted radiotherapy without chemotherapy for biomarker-selected LA-NSCLC patients. Materials/Methods: Patients with AJCC version 8 stage III NSCLC or unresectable stage II NSCLC and ECOG performance status 0-1 were eligible for this trial. Subjects with PD-L1 tumor proportion score (TPS) ≥ 50% received three cycles of induction pembrolizumab (200 mg, every 21 days), underwent restaging FDG-PET/CT, received risk-adapted thoracic radiotherapy (55 Gy delivered to tumors or lymph nodes with metabolic tumor volume exceeding 20 cc and 48 Gy delivered to smaller lesions, all in 20 daily fractions), and then received up to 13 cycles of additional pembrolizumab. Subjects with PD-L1 TPS \u3c 50% received concurrent chemoRT, and adjuvant durvalumab was recommended for patients without disease progression. The primary study endpoint was one-year progression-free survival (PFS) for subjects treated with pembrolizumab and radiotherapy (pembroRT), which we hypothesized would exceed 65%. Other study endpoints included 1-year overall survival (OS) and rates of clinician-scored (CTCAE v. 4.03) and patient-reported (PRO-CTCAE) adverse events observed over one year. Results: Twenty-five subjects with PD-L1 TPS ≥ 50% and 12 subjects with PD-L1 TPS \u3c 50% from three institutions were enrolled between August 2018 and November 2021. Median age was 70. Twenty-four subjects had stage II-IIIA disease, and 13 had stage IIIB-IIIC disease. Except for PD-L1 TPS, subject characteristics did not differ significantly across treatment groups. Ten out of the 12 subjects with ChemoRT received adjuvant durvalumab, and one received adjuvant osimertinib for EGFR mutation. The median follow-up duration is 15 months. Compared to patients treated with chemoRT, treatment with pembroRT has yielded numerically higher 1-year PFS (72% v. 46%, log rank p=0.232) and OS (91% v. 73%, log rank p=0.213) rates. Similar rates of grade 3 physician-scored adverse events have been observed with pembroRT (24%) and chemoRT (25%). Less severe patient-reported adverse events occurred with pembroRT compared to chemoRT (See Table). Conclusion: Treatment with pembrolizumab and risk-adapted radiotherapy without chemotherapy is a promising approach for LA-NSCLC patients with PD-L1 TPS ≥ 50%. In addition to yielding high disease control rates, this strategy appears to reduce patient-reported adverse events compared to standard chemoRT and adjuvant therapy

    Perturbation of Retinoid Homeostasis Increases Malformation Risk in Embryos Exposed to Pregestational Diabetes

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    Funding. This work was supported by funding from Hong Kong Research Grants Council General Research Fund project reference 441606 and 474109 to A.S.W.S., Y.C.L., C.C.W., P.J.M. and A.J.C..Peer reviewedPostprin

    Evidence for directional selection at a novel major histocompatibility class I marker in wild common frogs (Rana temporaria) exposed to a viral pathogen (Ranavirus).

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    (c) 2009 Teacher et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.Whilst the Major Histocompatibility Complex (MHC) is well characterized in the anuran Xenopus, this region has not previously been studied in another popular model species, the common frog (Rana temporaria). Nor, to date, have there been any studies of MHC in wild amphibian host-pathogen systems. We characterise an MHC class I locus in the common frog, and present primers to amplify both the whole region, and specifically the antigen binding region. As no more than two expressed haplotypes were found in over 400 clones from 66 individuals, it is likely that there is a single class I locus in this species. This finding is consistent with the single class I locus in Xenopus, but contrasts with the multiple loci identified in axolotls, providing evidence that the diversification of MHC class I into multiple loci likely occurred after the Caudata/Anura divergence (approximately 350 million years ago) but before the Ranidae/Pipidae divergence (approximately 230 mya). We use this locus to compare wild populations of common frogs that have been infected with a viral pathogen (Ranavirus) with those that have no history of infection. We demonstrate that certain MHC supertypes are associated with infection status (even after accounting for shared ancestry), and that the diseased populations have more similar supertype frequencies (lower F(ST)) than the uninfected. These patterns were not seen in a suite of putatively neutral microsatellite loci. We interpret this pattern at the MHC locus to indicate that the disease has imposed selection for particular haplotypes, and hence that common frogs may be adapting to the presence of Ranavirus, which currently kills tens of thousands of amphibians in the UK each year
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