96 research outputs found
Multi-Slot BLE Raw Database for Accurate Positioning in Mixed Indoor/Outdoor Environments
The technologies and sensors embedded in smartphones have contributed to the spread of
disruptive applications built on top of Location Based Services (LBSs). Among them, Bluetooth Low
Energy (BLE) has been widely adopted for proximity and localization, as it is a simple but efficient
positioning technology. This article presents a database of received signal strength measurements
(RSSIs) on BLE signals in a real positioning system. The system was deployed on two buildings
belonging to the campus of the University of Extremadura in Badajoz. the database is divided
into three different deployments, changing in each of them the number of measurement points
and the configuration of the BLE beacons. the beacons used in this work can broadcast up to six
emission slots simultaneously. Fingerprinting positioning experiments are presented in this work
using multiple slots, improving positioning accuracy when compared with the traditional single slot
approach
Impregnated palladium on magnetite as a water compatible catalyst for the cycloisomerization of alkynoic acid derivatives
This work describes the catalytic activity of palladium(II) species in the cycloisomerization of alkynoic acids and their derivatives in aqueous media as well as in Deep Eutectic Solvents (DESs), with one of the lowest metal catalyst loadings reported so far in the literature. Different substrates such as terminal and internal alkynes or alkynyl sulfonylimides were studied, obtaining selectivity either to the cyclic compound or the hydrolysed keto derivative. This new system avoids the use of harmful solvents and employs very efficient and recoverable heterogeneous catalysts.This work was supported by the University of Alicante (UAUSTI16-10, VIGROB-173), and the Spanish Ministerio de Economía, Industria y Competitividad (CTQ2015-66624-P). B. S. thanks the Generalitat Valenciana (ACIF/2017/211) for a fellowship. M. J. R.-A and J. G.-A. are indebted to the MINECO of Spain (CTQ2016-81797-REDC and CTQ2016-75986-P) and the Gobierno del Principado de Asturias (project GRUPIN14-006) for financial support. J. G.-A. thanks the Fundación BBVA for the award of a “Beca Leonardo a Investigadores y Creadores Culturales 2017”
Introducing glycerol as a sustainable solvent to organolithium chemistry : ultrafast chemoselective addition of aryllithium reagents to nitriles under air and at ambient temperature
Edging closer towards developing air and moisture compatible polar organometallic chemistry, the chemoselective and ultrafast addition of a range of aryllithium reagents to nitriles has been accomplished using glycerol as a solvent, at ambient temperature in the presence of air, establishing a novel sustainable access to aromatic ketones. Addition reactions occur heterogeneously ("on glycerol conditions"), where the lack of solubility of the nitriles in glycerol and the ability of the latter to form strong intermolecular H-bonds seem key to favouring nucleophilic addition over competitive hydrolysis. Remarkably, PhLi exhibits a greater resistance to hydrolysis working "on glycerol" conditions than "on water". Introducing glycerol as a new solvent in organolithium chemistry unlocks a myriad of opportunities for developing more sustainable, air and moisture tolerant main-group-metal-mediated organic synthesis
Looking for blazars in a sample of unidentified high-energy emitting Fermi sources
Context. Based on their overwhelming dominance among associated Fermi γ-ray catalogue sources, it is expected that a large fraction of the unidentified Fermi objects are blazars. Through crossmatching between the positions of unidentified γ-ray sources from the First Fermi Catalog of γ-ray sources emitting above 10 GeV (1FHL) and the ROSAT and Swift/XRT catalogues of X-ray objects and between pointed XRT observations, a sample of 36 potential associations was found in previous works with less than 15 arcsec of positional offset. One-third of them have recently been classified; the remainder, though believed to belong to the blazar class, still lack spectroscopic classifications. Aims. We study the optical spectrum of the putative counterparts of these unidentified gamma-ray sources in order to find their redshifts and to determine their nature and main spectral characteristics. Methods. An observational campaign was carried out on the putative counterparts of 13 1FHL sources using medium-resolution optical spectroscopy from the Osservatorio Astronomico di Bologna in Loiano, Italy; the Telescopio Nazionale Galileo and the Nordic Optical Telescope, both in the Canary Islands, Spain; and the Observatorio Astronómico Nacional San Pedro Mártir in Baja California, Mexico. Results. We were able to classify 14 new objects based on their continuum shapes and spectral features. Conclusions. Twelve new blazars were found, along with one new quasar and one new narrow line Seyfert 1 (NLS1) to be potentially associated with the 1FHL sources of our sample. Redshifts or lower limits were obtained when possible alongside central black hole mass and luminosity estimates for the NLS1 and the quasar.Fil: Marchesini, Ezequiel Joaquín. Universidad Nacional de la Plata. Facultad de Ciencias Astronómicas y Geofísicas; ArgentinaFil: Masetti, Nicola. Istituto di Astrofisica Spaziale e Fisica Cosmica di Bologna; ItaliaFil: Chavushyan, V.. Instituto Nacional de Astrofísica, Óptica y Electrónica; MéxicoFil: Cellone, Sergio Aldo. Universidad Nacional de la Plata. Facultad de Ciencias Astronómicas y Geofísicas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Astrofísica La Plata. Universidad Nacional de La Plata. Facultad de Ciencias Astronómicas y Geofísicas. Instituto de Astrofísica La Plata; ArgentinaFil: Andruchow, Ileana. Universidad Nacional de la Plata. Facultad de Ciencias Astronómicas y Geofísicas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Astrofísica La Plata. Universidad Nacional de La Plata. Facultad de Ciencias Astronómicas y Geofísicas. Instituto de Astrofísica La Plata; ArgentinaFil: Bassani, L.. Istituto di Astrofisica Spaziale e Fisica Cosmica di Bologna; ItaliaFil: Bazzano, A.. Istituto di Astrofisica e Planetologia Spaziali; ItaliaFil: Jiménez-Bailón, E.. Universidad Nacional Autónoma de México; MéxicoFil: Landi, R.. Istituto di Astrofisica Spaziale e Fisica Cosmica di Bologna; ItaliaFil: Malizia, A.. Istituto di Astrofisica Spaziale e Fisica Cosmica di Bologna; ItaliaFil: Palazzi, E.. Istituto di Astrofisica Spaziale e Fisica Cosmica di Bologna; ItaliaFil: Patiño Álvarez, V.. Instituto Nacional de Astrofísica, Óptica y Electrónica; MéxicoFil: Rodríguez Castillo, G. A.. Osservatorio Astronomico di Roma; ItaliaFil: Stephen, J. B.. Istituto di Astrofisica Spaziale e Fisica Cosmica di Bologna; ItaliaFil: Ubertini, P.. Istituto di Astrofisica e Planetologia Spaziali; Itali
Risk of gastrointestinal cancer in a symptomatic cohort after a complete colonoscopy: Role of faecal immunochemical test
BACKGROUND: Faecal immunochemical test (FIT) has been recommended to assess symptomatic patients for colorectal cancer (CRC) detection. Nevertheless, some conditions could theoretically favour blood originating in proximal areas of the gastrointestinal tract passing through the colon unmetabolized. A positive FIT result could be related to other gastrointestinal cancers (GIC). AIM To assess the risk of GIC detection and related death in FIT-positive symptomatic patients (threshold 10 mu g Hb/g faeces) without CRC. METHODS: Post hoc cohort analysis performed within two prospective diagnostic test studies evaluating the diagnostic accuracy of different FIT analytical systems for CRC and significant colonic lesion detection. Ambulatory patients with gastrointestinal symptoms referred consecutively for colonoscopy from primary and secondary healthcare, underwent a quantitative FIT before undergoing a complete colonoscopy. Patients without CRC were divided into two groups (positive and negative FIT) using the threshold of 10 mu g Hb/g of faeces and data from follow-up were retrieved from electronic medical records of the public hospitals involved in the research. We determined the cumulative risk of GIC, CRC and upper GIC. Hazard rate (HR) was calculated adjusted by age, sex and presence of significant colonic lesion. RESULTS: We included 2709 patients without CRC and a complete baseline colonoscopy, 730 (26.9%) with FIT >= 10 mu gr Hb/gr. During a mean time of 45.5 +/- 20.0 mo, a GIC was detected in 57 (2.1%) patients: An upper GIC in 35 (1.3%) and a CRC in 14 (0.5%). Thirty-six patients (1.3%) died due to GIC: 22 (0.8%) due to an upper GIC and 9 (0.3%) due to CRC. FIT-positive subjects showed a higher CRC risk (HR 3.8, 95%CI: 1.2-11.9) with no differences in GIC (HR 1.5, 95%CI: 0.8-2.7) or upper GIC risk (HR 1.0, 95%CI: 0.5-2.2). Patients with a positive FIT had only an increased risk of CRC-related death (HR 10.8, 95%CI: 2.1-57.1) and GIC-related death (HR 2.2, 95%CI: 1.1-4.3), with no differences in upper GIC-related death (HR 1.4, 95%CI: 0.6-3.3). An upper GIC was detected in 22 (0.8%) patients during the first year. Two variables were independently associated: anaemia (OR 5.6, 95%CI: 2.2-13.9) and age >= 70 years (OR 2.7, 95%CI: 1.1-7.0). CONCLUSION Symptomatic patients without CRC have a moderate risk increase in upper GIC, regardless of the FIT result. Patients with a positive FIT have an increased risk of post-colonoscopy CRC
Study of the break-up channel in 11Li+208Pb collisions at energies around the Coulomb barrier
We present a study of 11Li+208 Pb collisions at energies around the Coulomb barrier (Elab = 24.3 and 29.8 MeV), measured at the post-accelerated beam facility, ISAC II, at TRIUMF (Vancouver, Canada). A remarkably large yield of 9Li has been observed, a result that is attributed to the weak binding of the 11Li nucleus. The angular distribution of this 9Li yield, relative to the elastic one, has been analysed in terms of first-order semiclassical calculations as well as four-body and three-body Continuum-Discretized Coupled-Channels (CDCC) calculations, based on a three-body and di-neutron model of the 11Li nucleus, respectively. The calculations reproduce well the trend of the data and support the existence of a large concentration of B (E1) strength at very low excitation energies. The connection of this large B (E1) with a possible low-lying dipole resonance is discussed
Los Países Bálticos y su adhesión a la UE Algunas claves para el futuro
Tras su independencia en 1991, los Países Bálticos han tenido una fuerte transformación estructural
de sus tejidos productivos y, de manera especial, de sus sistemas financieros que hubo que rediseñar desde la base. En el éxito de este proceso tuvo una gran importancia la utilización de un “Currency Board Agreement” (CBA) entre la corona estonia e, inicialmente, el marco alemán, proceso que fue acercando gradualmente a esta república báltica hacia la Unión Europea (UE). El objetivo de este trabajo es doble: (1) analizar cuáles han sido las causas, siguiendo un análisis DAFO, que han permitido a Estonia ser uno de los países candidatos para la próxima ampliación comunitaria que tendrá efecto en el 2004, y (2) la importancia que ha tenido el CBA como estrategia de acercamiento hacia la UE y de alejamiento del área rublo, así como los efectos de la utilización del euro como moneda única europea
Looking for blazars in a sample of unidentified high-energy emitting Fermi sources
Context. Based on their overwhelming dominance among associated Fermi γ-ray catalogue sources, it is expected that a large fraction of the unidentified Fermi objects are blazars. Through crossmatching between the positions of unidentified γ-ray sources from the First Fermi Catalog of γ-ray sources emitting above 10 GeV (1FHL) and the ROSAT and Swift/XRT catalogues of X-ray objects and between pointed XRT observations, a sample of 36 potential associations was found in previous works with less than 15 arcsec of positional offset. One-third of them have recently been classified; the remainder, though believed to belong to the blazar class, still lack spectroscopic classifications.
Aims. We study the optical spectrum of the putative counterparts of these unidentified gamma-ray sources in order to find their redshifts and to determine their nature and main spectral characteristics.
Methods. An observational campaign was carried out on the putative counterparts of 13 1FHL sources using medium-resolution optical spectroscopy from the Osservatorio Astronomico di Bologna in Loiano, Italy; the Telescopio Nazionale Galileo and the Nordic Optical Telescope, both in the Canary Islands, Spain; and the Observatorio Astronómico Nacional San Pedro Mártir in Baja California, Mexico.
Results. We were able to classify 14 new objects based on their continuum shapes and spectral features.
Conclusions. Twelve new blazars were found, along with one new quasar and one new narrow line Seyfert 1 (NLS1) to be potentially associated with the 1FHL sources of our sample. Redshifts or lower limits were obtained when possible alongside central black hole mass and luminosity estimates for the NLS1 and the quasar.Facultad de Ciencias Astronómicas y GeofísicasInstituto de Astrofísica de La Plat
MWP true time delay implemented in PbS-SU8 waveguides
Es presenta un nou tipus de dispositiu de retard en temps real de microones (TTD) basat en la dispersió de punts quàntics col·loïdals PbS (QD) en el fotoresist SU8 disponible comercialment. Amb aquest propòsit, els nanocompostos PbS-SU8 s’integren en una plataforma de silici en forma de guies d’ones de cresta. Quan aquestes estructures es bomben a longituds d’ona per sota de l’interval de banda dels PbS QD, es realitza un desplaçament de fase en un senyal de microones transmès òpticament (a 1550 nm) i, per tant, es produeix un retard temporal. A més, es milloren els resultats mitjançant la implementació d’una nova guia d’ones de doble capa de cresta composta per un nanocompost PbS-SU8 i una capa passiva SU8 que redueix les pèrdues degudes al feix de la bomba i, per tant, millorar l’excitació dels QD. El dispositiu resultant mostra avantatges potencials respecte a les tecnologies TTD actuals, ja que permet una ràpida sintonització del retard temporal controlant la potència de la bomba i un alt nivell d’integració a causa de la seva petita mida i el material utilitzat.JCI-2012-14805FPU 13/04675PROMETEO II/2013/012EU-NAVOLCHI project 288869TEC2011-29120-C05-01TEC2011-29120-C05-05A new kind of microwave true time delay (TTD) device based on the dispersion of PbS colloidal quantum dots (QDs) in the commercially available photoresist SU8 is presented. For this purpose PbS-SU8 nanocomposites are integrated on a silicon platform in the form of ridge waveguides. When these structures are pumped at wavelengths below the band-gap of the PbS QDs, a phase shift in an optically conveyed (at 1550 nm) microwave signal is performed and therefore a temporal delay is produced. Furthermore, results are improved by implementing a novel ridge bilayer waveguide composed by a PbS-SU8 nanocomposite and a SU8 passive layer that reduces the losses due to the pump beam, and hence to improve the excitation of the QDs. The resulting device shows potential benefits respect to the current TTD technologies since it allows a fast tunability of the temporal delay by controlling the pump power and a high level of integration due to its small size and the material used
Prevention of ventilator-associated pneumonia: the multimodal approach of the spanish ICU pneumonia zero program.
Objectives:
The “Pneumonia Zero” project is a nationwide multimodal intervention based on the simultaneous implementation of a comprehensive evidence-based bundle measures to prevent ventilator-associated pneumonia in critically ill patients admitted to the ICU.
Design:
Prospective, interventional, and multicenter study.
Setting:
A total of 181 ICUs throughout Spain.
Patients:
All patients admitted for more than 24 hours to the participating ICUs between April 1, 2011, and December 31, 2012.
Intervention:
Ten ventilator-associated pneumonia prevention measures were implemented (seven were mandatory and three highly recommended). The database of the National ICU-Acquired Infections Surveillance Study (Estudio Nacional de Vigilancia de Infecciones Nosocomiales [ENVIN]) was used for data collection. Ventilator-associated pneumonia rate was expressed as incidence density per 1,000 ventilator days. Ventilator-associated pneumonia rates from the incorporation of the ICUs to the project, every 3 months, were compared with data of the ENVIN registry (April–June 2010) as the baseline period. Ventilator-associated pneumonia rates were adjusted by characteristics of the hospital, including size, type (public or private), and teaching (postgraduate) or university-affiliated (undergraduate) status.
Measurements and Main Results:
The 181 participating ICUs accounted for 75% of all ICUs in Spain. In a total of 171,237 ICU admissions, an artificial airway was present on 505,802 days (50.0% of days of stay in the ICU). A total of 3,474 ventilator-associated pneumonia episodes were diagnosed in 3,186 patients. The adjusted ventilator-associated pneumonia incidence density rate decreased from 9.83 (95% CI, 8.42–11.48) per 1,000 ventilator days in the baseline period to 4.34 (95% CI, 3.22–5.84) after 19–21 months of participation.
Conclusions:
Implementation of the bundle measures included in the “Pneumonia Zero” project resulted in a significant reduction of more than 50% of the incidence of ventilator-associated pneumonia in Spanish ICUs. This reduction was sustained 21 months after implementation
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