1,940 research outputs found

    Self-organized evolution in socio-economic environments

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    We propose a general scenario to analyze social and economic changes in modern environments. We illustrate the ideas with a model that incorporating the main trends is simple enough to extract analytical results and, at the same time, sufficiently complex to display a rich dynamic behavior. Our study shows that there exists a macroscopic observable that is maximized in a regime where the system is critical, in the sense that the distribution of events follow power-laws. Computer simulations show that, in addition, the system always self-organizes to achieve the optimal performance in the stationary state.Comment: 4 pages RevTeX; needs epsf.sty and rotate.sty; submitted to Phys Rev Let

    LabVIEW-based control and acquisition system for the dosimetric characterization of a silicon strip detector

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    Theaimofthisworkistopresentanewdataacquisition,control,andanalysissoftwaresystemwrittenin LabVIEW.Thissystemhasbeendesignedtoobtainthedosimetryofasiliconstripdetectorinpolyethylene. It allows the full automation of the experiments and data analysis required for the dosimetric characterization of silicon detectors. It becomes a useful tool that can be applied in the daily routine check of a beam accelerator.MINECO ICTI2013-2016/FPA2013-47327-C2-1-RMINECO ICTI2013-2016/FPA2014-53290-C2-2- PJunta de Andalucía P12-FQM-160

    A comparative analysis of Airbnb in London and Barcelona: The ethnographic research process and its discontents

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    Peer to peer (P2P) accommodation platforms like Airbnb or HomeAway have transformed not only the hospitality industry but they have also created wider economic change in other adjacent industries and in society in general. Because of this, many stakeholders are now trying to proactively shape the evolution of these platforms, as reflected by numerous actions by policymakers, industry representatives, media outlets and the public across the world. This paper reports on the authors’ experience conducting a comparative study over a period of one year and a half researching issues surrounding the sharing economy, by using Airbnb as a case study. The city-based case study (London and Barcelona) examines the experiences and views of relevant stakeholders in the Airbnb sphere: hosts, guests, Airbnb public policy managers, rental apartment companies, council representatives and other local authorities. The barriers and opportunities for ethical practice were also identified and reported according to the views of these stakeholders. Our main contribution is the identification of the challenges derived from conducting research of complex nature, as in the case of comparative studies in two international settings, focusing on a controversial phenomenon, in this case, the sharing economy platform Airbnb. We also reflect on some of the strategies that we used to overcome some of these challenges with the aim of supporting other researchers working in a similar context. By using participant observation, in-depth interviews and focus groups, this study gathers different perspectives on the complex topic of the operation of Airbnb in two European cities, London and Barcelona, that are also major tourist destinations

    Biomarkers predicting the controller dose of omalizumab in patients with chronic spontaneous urticaria

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    Background Clinical trials showed the efficacy of 300 mg/4 weeks of omalizumab (OMA) during 6 months in patients with severe chronic spontaneous urticaria (CSU). Nevertheless, in real life, many patients require higher doses and/or longer treatment. This study assesses the real-life performance of OMA in severe CSU and identifies factors associated with the response. Methods CSU patients eligible for OMA were recruited prospectively. Clinical data and a blood test were collected before OMA initiation. Urticaria Activity Score 7 (UAS7) was calculated at baseline and every 3 months during OMA treatment. CSU control was defined as UAS7 <7 points. This work was partially sponsored by OMA manufacturer. Results Eighty-nine adults (19.1% males) with severe CSU were recruited. Median duration of CSU prior to OMA initiation was 2 years, and median severity by UAS7 at baseline was 24 points (range 10–42 points). OMA controlled 94.4% of patients, but 17.9% of responders required doses >300 mg/4 weeks. A blood basophil count >20 cells/μL (OR 13.33; 95% CI 3.32–52.63; p 29 months at the end of the study (active responders, AR). AR had received OMA for a median of 45 months (30–100 months). There were no significant differences in clinical or analytical factors between RR and AR patients. Conclusions Low blood basophil count and the presence of hypothyroidism might serve as biomarkers for the controller dose of OMA in severe CSU patients.Funding for open Access charge: Universidad de Málaga / CBUA. Instituto de Salud Carlos III; Novartis Pharmaceuticals Corporation; Consejería de Salud y Bienestar Social, Junta de Andalucí

    Effect of butanol and salt concentration on solid-state nanopores resistance

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    The objective of this study was to demonstrate the possibility of using 1-butanol to detect in a reliable way the open pore current of pyramidal solid-state nanopores produced in silicon wafers. The nanopores were produced through controlled pore formation by neutralizing an etchant (KOH) with a strong acid (HCl). Since nanopores produced by this method have a larger depth than those made in nanometer thick membranes, they behave as nanochannels. As a consequence, the open pore current detection is more challenging. Thus, we report that low amounts of butanol considerably aid in the detection of the open pore current of nanopores.Fil: Vega, M.. Universidad Tecnológica Nacional. Facultad Regional Haedo; ArgentinaFil: Perez, Maximiliano Sebastian. Universidad Tecnológica Nacional. Facultad Regional Haedo; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Granell, Pablo Nicolás. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Golmar, Federico. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Wloka, C.. University of Groningen; Países BajosFil: Maglia, G.. University of Groningen; Países BajosFil: Dieguez, M.J.. Instituto Nacional de Tecnología Agropecuaria; ArgentinaFil: Del Valle, E.M.. Universidad de Salamanca; EspañaFil: Lasorsa, Carlos Alberto. Universidad Tecnológica Nacional. Facultad Regional Haedo; ArgentinaFil: Lerner, Betiana. Universidad Tecnológica Nacional. Facultad Regional Haedo; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

    Non-Gaussianity from Instant and Tachyonic Preheating

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    We study non-Gaussianity in two distinct models of preheating: instant and tachyonic. In instant preheating non-Gaussianity is sourced by the local terms generated through the coupled perturbations of the two scalar fields. We find that the non-Gaussianity parameter is given by fNLϕ2g<O(1)f_{NL}^{\phi}\sim 2g < O(1), where gg is a coupling constant, so that instant preheating is unlikely to be constrained by WMAP or Planck. In the case of tachyonic preheating non-Gaussianity arises solely from the instability of the tachyon matter and is found to be large. We find that for single field inflation the present WMAP data implies a bound V01/4/MP104V_{0}^{1/4}/M_{P}\leq 10^{-4} on the scale of tachyonic instability. We argue that the tachyonic preheating limits are useful also for string-motivated inflationary models.Comment: 12 pages, 1 figure, additional discussion, improved constraint on the scale of tachyonic preheatin
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