8,495 research outputs found

    Evaluation of the use of a City Center through the use of Bluetooth Sensors Network

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    In order to achieve the objectives of Smart Cities, public administrations need to take measures to regulate mobility, which undoubtedly requires a high level of information and sensorization. Until the implementation of the connected vehicle takes place, it is still necessary to install sensors to obtain information about mobility. Bluetooth sensors are becoming a useful tool due to the low cost of equipment and installation. The use of Bluetooth sensors in cities, with short distances between sensors, makes it necessary to propose new classification algorithms that allow the trips of pedestrians and vehicles to be differentiated. This article presents the study carried out in the city of Valencia to determine the use of motor vehicles in the historic center and propose a new classification algorithm to distinguish between an onboard Bluetooth device and the same device carried by a pedestrian when it is not possible to use the travel time for the classification due to the short distance between sensors. This causes very similar or even indistinguishable travel times for vehicles and for pedestrians. We also propose an algorithm that allows vehicles to be classified according to what type of trip is made always through the historical center of Valencia, whether it is to make a shorter itinerary through the city or to access the center for any type of business. This algorithm would enable the Origin-Destination matrix of an urban network with short distances between sensors if they are available in all entries and exits. Likewise, the results obtained have allowed to positively evaluate the algorithm defined to distinguish between trips made by a pedestrian or a vehicle in a city, using the MAC address of their mobile devices with very short distances among sensors. The results of this study show that it is possible to use Bluetooth technology, with low cost installations, to evaluate the use of the city by motor vehicles

    Learning a Battery of COVID-19 Mortality Prediction Models by Multi-objective Optimization

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    The COVID-19 pandemic is continuously evolving with drastically changing epidemiological situations which are approached with different decisions: from the reduction of fatalities to even the selection of patients with the highest probability of survival in critical clinical situations. Motivated by this, a battery of mortality prediction models with different performances has been developed to assist physicians and hospital managers. Logistic regression, one of the most popular classifiers within the clinical field, has been chosen as the basis for the generation of our models. Whilst a standard logistic regression only learns a single model focusing on improving accuracy, we propose to extend the possibilities of logistic regression by focusing on sensitivity and specificity. Hence, the log-likelihood function, used to calculate the coefficients in the logistic model, is split into two objective functions: one representing the survivors and the other for the deceased class. A multi-objective optimization process is undertaken on both functions in order to find the Pareto set, composed of models not improved by another model in both objective functions simultaneously. The individual optimization of either sensitivity (deceased patients) or specificity (survivors) criteria may be conflicting objectives because the improvement of one can imply the worsening of the other. Nonetheless, this conflict guarantees the output of a battery of diverse prediction models. Furthermore, a specific methodology for the evaluation of the Pareto models is proposed. As a result, a battery of COVID-19 mortality prediction models is obtained to assist physicians in decision-making for specific epidemiological situations.This research is supported by the Basque Government (IT1504- 22, Elkartek) through the BERC 2022–2025 program and BMTF project, and by the Ministry of Science, Innovation and Universities: BCAM Severo Ochoa accreditation SEV-2017-0718 and PID2019-104966GB-I00. Furthermore, the work is also supported by the AXA Research Fund project “Early prognosis of COVID-19 infections via machine learning”

    A spectroscopic atlas of post-AGB stars and planetary nebulae selected from the IRAS Point Source Catalogue

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    Aims: We study the optical spectral properties of a sample of stars showing far infrared colours similar to those of well-known planetary nebulae. The large majority of them were unidentified sources or poorly known in the literature at the time when this spectroscopic survey started, some 15 years ago. Methods: We present low-resolution optical spectroscopy, finding charts and improved astrometric coordinates of a sample of 253 IRAS sources. Results: We have identified 103 sources as post-AGB stars, 21 as ``transition sources'', and 36 as planetary nebulae, some of them strongly reddened. Among the rest of sources in the sample, we were also able to identify 38 young stellar objects, 5 peculiar stars, and 2 Seyfert galaxies. Up to 49 sources in our spectroscopic sample do not show any optical counterpart, and most of them are suggested to be heavily obscured post-AGB stars, rapidly evolving on their way to becoming planetary nebulae. Conclusions: An analysis of the galactic distribution of the sources identified as evolved stars in the sample is presented together with a study of the distribution of these stars in the IRAS two-colour diagram. Finally, the spectral type distribution and other properties of the sources identified as post-AGB in this spectroscopic survey are discussed in the framework of stellar evolution.Comment: 69 pages, 413 figures. Accepted by Astronomy and Astrophysic

    Observation of insulator-metal transition in EuNiO3_{3} under high pressure

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    The charge transfer antiferromagnetic (TN_{N} =220 K) insulator EuNiO3_{3} undergoes, at ambient pressure, a temperature-induced metal insulator MI transition at TMI_{MI}=463 K. We have investigated the effect of pressure (up to p~20 GPa) on the electronic, magnetic and structural properties of EuNiO3_{3} using electrical resistance measurements, {151}^Eu nuclear resonance scattering of synchrotron radiation and x-ray diffraction, respectively. With increasing pressure we find at pc_{c} =5.8 GPa a transition from the insulating state to a metallic state, while the orthorhombic structure remains unchanged up to 20 GPa. The results are explained in terms of a gradual increase of the electronic bandwidth with increasing pressure, which results in a closing of the charge transfer gap. It is further shown that the pressure-induced metallic state exhibits magnetic order with a lowervalue of TN_{N} (TN_{N} ~120 K at 9.4 GPa) which disappears between 9.4 and 14.4 GPa.Comment: 10 pages, 3 figure

    Clinical impact of a pharmacist-led medication review with follow up for aged polypharmacy patients: A cluster randomized controlled trial

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    Background: Medication review with follow-up (MRF) is a service where community pharmacists undertake a medication review with monthly follow-up to provide continuing care. The ConSIGUE Program assessed the impact and implementation of MRF for aged polypharmacy patients in Spanish Community Pharmacies. The present paper reports on the clinical impact evaluation phase of ConSIGUE. Objective: The main objective of the study was to measure the effect of MRF on the primary outcome of the number of uncontrolled health problems. Secondary objectives were to analyze the drug-related problems (DRPs) identified as potential causes of ineffective or unsafe medications and the pharmacists’ interventions implemented during MRF provision. Methods: An open-label multi-centered cluster randomized study with comparison group (CG) was carried out in community pharmacies from 4 provinces in Spain during 6 months. The main inclusion criteria were patients over 64 years old, using 5 or more medicines. The intervention group (IG) received the MRF service (advanced medication review-type 3 MR) whereas patients in the CG received usual care. Results: 178 pharmacies recruited 1403 patients (IG= 688 patients; CG= 715 patients). During the 6 months of the study 72 patients were lost to follow up. The adjusted multi-level random effects models showed a significant reduction in the number of uncontrolled health problems over the periods in the IG (-0.72, 95% CI: -0.80, -0.65) and no change in the CG (-0.03, 95%CI: -0.10, 0.04). Main DRPs identified as potential causes of failures of uncontrolled health problems’ treatment were undertreated condition (559 DRPs; 35.81%), lack of treatment adherence (261 DRP; 16.67%) and risk of adverse effects (207 DRPs; 13.53%). Interventions performed by pharmacist to solve DRP mainly included the addition (246 interventions; 14.67%) and change (330 interventions; 19.68%) of a medicine and educational interventions on medicine adherence (231 interventions; 13.78%) and non-pharmacological interventions (369 interventions; 22.01%). Conclusions: This study provides evidence of the impact of community pharmacist on clinical outcomes for aged patients. It suggests that the provision of an MRF in collaboration with general medical practitioners and patients contributes to the improvement of aged polypharmacy patients’ health status and reduces their problems related with the use of medicines.Cinfa Laboratorie

    Young Planetary Nebulae: Hubble Space Telescope Imaging and a New Morphological Classification System

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    Using Hubble Space Telescope images of 119 young planetary nebulae, most of which have not previously been published, we have devised a comprehensive morphological classification system for these objects. This system generalizes a recently devised system for pre-planetary nebulae, which are the immediate progenitors of planetary nebulae (PNs). Unlike previous classification studies, we have focussed primarily on young PNs rather than all PNs, because the former best show the influences or symmetries imposed on them by the dominant physical processes operating at the first and primary stage of the shaping process. Older PNs develop instabilities, interact with the ambient interstellar medium, and are subject to the passage of photoionization fronts, all of which obscure the underlying symmetries and geometries imposed early on. Our classification system is designed to suffer minimal prejudice regarding the underlying physical causes of the different shapes and structures seen in our PN sample, however, in many cases, physical causes are readily suggested by the geometry, along with the kinematics that have been measured in some systems. Secondary characteristics in our system such as ansae indicate the impact of a jet upon a slower-moving, prior wind; a waist is the signature of a strong equatorial concentration of matter, whether it be outflowing or in a bound Keplerian disk, and point symmetry indicates a secular trend, presumably precession, in the orientation of the central driver of a rapid, collimated outflow.Comment: (to appear in The Astronomical Journal, March 2011.) The quality of the figures as it appears in the arXiv pdf output is not up-to-par; the full ms with high-quality figures is available by anonymous FTP at ftp://ftp.astro.ucla.edu/pub/morris/sahai_AJ_360163.pd

    The HADES RV Programme with HARPS-N@TNG II. Data treatment and simulations

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    The distribution of exoplanets around low-mass stars is still not well understood. Such stars, however, present an excellent opportunity of reaching down to the rocky and habitable planet domains. The number of current detections used for statistical purposes is still quite modest and different surveys, using both photometry and precise radial velocities, are searching for planets around M dwarfs. Our HARPS-N red dwarf exoplanet survey is aimed at the detection of new planets around a sample of 78 selected stars, together with the subsequent characterization of their activity properties. Here we investigate the survey performance and strategy. From 2700 observed spectra, we compare the radial velocity determinations of the HARPS-N DRS pipeline and the HARPS-TERRA code, we calculate the mean activity jitter level, we evaluate the planet detection expectations, and we address the general question of how to define the strategy of spectroscopic surveys in order to be most efficient in the detection of planets. We find that the HARPS-TERRA radial velocities show less scatter and we calculate a mean activity jitter of 2.3 m/s for our sample. For a general radial velocity survey with limited observing time, the number of observations per star is key for the detection efficiency. In the case of an early M-type target sample, we conclude that approximately 50 observations per star with exposure times of 900 s and precisions of about 1 m/s maximizes the number of planet detections

    Evaluation of the Impact of the COVID-19 Lockdown in the Clinical Course of Migraine

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    Objective: Previous studies have demonstrated that emotional stress, changes in lifestyle habits and infections can worsen the clinical course of migraine. We hypothesize that changes in habits and medical care during coronavirus disease 2019 (COVID-19) lockdown might have worsened the clinical course of migraine. Design: Retrospective survey study collecting online responses from migraine patients followed-up by neurologists at three tertiary hospitals between June and July 2020. Methods: We used a web-based survey that included demographic data, clinical variables related with any headache (frequency) and migraine (subjective worsening, frequency, and intensity), lockdown, and symptoms of post-traumatic stress. Results: The response rate of the survey was 239/324 (73.8%). The final analysis included 222 subjects. Among them, 201/222 (90.5%) were women, aged 42.5 ± 12.0 (mean±SD). Subjective improvement of migraine during lockdown was reported in 31/222 participants (14.0%), while worsening in 105/222 (47.3%) and was associated with changes in migraine triggers such as stress related to going outdoors and intake of specific foods or drinks. Intensity of attacks increased in 67/222 patients (30.2%), and it was associated with the subjective worsening, female sex, recent insomnia, and use of acute medication during a headache. An increase in monthly days with any headache was observed in 105/222 patients (47.3%) and was related to symptoms of post-traumatic stress, older age and living with five or more people. Conclusions: Approximately half the migraine patients reported worsening of their usual pain during the lockdown. Worse clinical course in migraine patients was related to changes in triggers and the emotional impact of the lockdown. © 2021 The Author(s) 2021. Published by Oxford University Press on behalf of the American Academy of Pain Medicine

    Candidate planetary nebulae in the IPHAS photometric catalogue

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    Original article can be found at: http://www.aanda.org/ Copyright European Southern Observatory. DOI: 10.1051/0004-6361/200912002Context. We have carried out a semi-automated search for planetary nebulae (PNe) in the INT photometric H-alpha survey (IPHAS) catalogue. We present the PN search and the list of selected candidates. We cross correlate the selected candidates with a number of existing infrared galactic surveys in order to gain further insight into the nature of the candidates. Spectroscopy of a subset of objects is used to estimate the number of PNe present in the entire candidate list. Aims. The overall aim of the IPHAS PN project is to carry out a deep census of PNe in the northern Galactic plane, an area where PN detections are clearly lacking. Methods. The PN search is carried out on the IPHAS photometric catalogue. The candidate selection is based on the IPHAS and 2MASS/UKIDSS colours of the objects and the final candidate selection is made visually. Results. From the original list of ~600 million IPHAS detections we have selected a total of 1005 objects. Of these, 224 are known objects, leaving us with 781 PN candidates. Based on the initial follow-up spectroscopy, we expect the list to include very young and proto-PNe in addition to genuine, normal PNe (~16%) and emission line objects other than PNe. We present additional criteria to select the most probable PN candidates from our candidate list.Peer reviewe
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