19 research outputs found

    Particle Sensor Using Solidly Mounted Resonators

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    This paper describes the development of a novel particle sensing system employing zinc oxide based solidly mounted resonator (SMR) devices for the detection of airborne fine particles (i.e., PM2.5 and PM10). The system operates in a dual configuration in which two SMR devices are driven by Colpitts-type oscillators in a differential mode. Particles are detected by the frequency shift caused by the mass of particles present on one resonator with while the other acts as a reference channel. Experimental validation of the system was performed inside an environmental chamber using a dust generator with the particles of known size and concentration. A sensor sensitivity of 4.6 Hz per μg/m3 was demonstrated for the SMRs resonating at a frequency of 970 MHz. Our results demonstrate that the SMR-based system has the potential to be implemented in CMOS technology as a low-cost, miniature smart particle detector for the real-time monitoring of airborne particles

    Remote Laboratories for Teaching and Training in Engineering

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    Typical mechatronic systems are a combination of advanced technologies involving several disciplines. This multidisciplinary approach to the development of industrial applications provides great opportunities for the implementation of e-learning environments and collaborative schemes. Engineering education, in particular, benefits from many of these advances, among which, virtual instrumentation is a useful tool for the development of virtual environments, e-learning spaces and, particularly, remote laboratories. This chapter describes the implementation of web-based laboratories that allow the remote operation of experiments used as training exercises in undergraduate engineering courses. The remote laboratories were developed using LabVIEW® software, and they enable remote control and monitoring of laboratory equipment, allowing engineering students to perform experiments in real time, at their own pace, from anywhere, and whenever is suitable for them. Besides the experimental training that the web-based laboratories provide to students, the system is also a powerful teaching tool since real-time demonstrations of the experiments can be performed, and they also can be simultaneously monitored by a group of students. This approach is highly beneficial for engineering schools in developing countries, as resources can be shared through the Internet. A description of the system and three proposed experiments is presented, together with the experimental results

    Search for Eccentric Black Hole Coalescences during the Third Observing Run of LIGO and Virgo

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    Despite the growing number of confident binary black hole coalescences observed through gravitational waves so far, the astrophysical origin of these binaries remains uncertain. Orbital eccentricity is one of the clearest tracers of binary formation channels. Identifying binary eccentricity, however, remains challenging due to the limited availability of gravitational waveforms that include effects of eccentricity. Here, we present observational results for a waveform-independent search sensitive to eccentric black hole coalescences, covering the third observing run (O3) of the LIGO and Virgo detectors. We identified no new high-significance candidates beyond those that were already identified with searches focusing on quasi-circular binaries. We determine the sensitivity of our search to high-mass (total mass M>70M>70 MM_\odot) binaries covering eccentricities up to 0.3 at 15 Hz orbital frequency, and use this to compare model predictions to search results. Assuming all detections are indeed quasi-circular, for our fiducial population model, we place an upper limit for the merger rate density of high-mass binaries with eccentricities 0<e0.30 < e \leq 0.3 at 0.330.33 Gpc3^{-3} yr1^{-1} at 90\% confidence level.Comment: 24 pages, 5 figure

    Mortality of emergency abdominal surgery in high-, middle- and low-income countries

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    Background: Surgical mortality data are collected routinely in high-income countries, yet virtually no low- or middle-income countries have outcome surveillance in place. The aim was prospectively to collect worldwide mortality data following emergency abdominal surgery, comparing findings across countries with a low, middle or high Human Development Index (HDI). Methods: This was a prospective, multicentre, cohort study. Self-selected hospitals performing emergency surgery submitted prespecified data for consecutive patients from at least one 2-week interval during July to December 2014. Postoperative mortality was analysed by hierarchical multivariable logistic regression. Results: Data were obtained for 10 745 patients from 357 centres in 58 countries; 6538 were from high-, 2889 from middle- and 1318 from low-HDI settings. The overall mortality rate was 1⋅6 per cent at 24 h (high 1⋅1 per cent, middle 1⋅9 per cent, low 3⋅4 per cent; P < 0⋅001), increasing to 5⋅4 per cent by 30 days (high 4⋅5 per cent, middle 6⋅0 per cent, low 8⋅6 per cent; P < 0⋅001). Of the 578 patients who died, 404 (69⋅9 per cent) did so between 24 h and 30 days following surgery (high 74⋅2 per cent, middle 68⋅8 per cent, low 60⋅5 per cent). After adjustment, 30-day mortality remained higher in middle-income (odds ratio (OR) 2⋅78, 95 per cent c.i. 1⋅84 to 4⋅20) and low-income (OR 2⋅97, 1⋅84 to 4⋅81) countries. Surgical safety checklist use was less frequent in low- and middle-income countries, but when used was associated with reduced mortality at 30 days. Conclusion: Mortality is three times higher in low- compared with high-HDI countries even when adjusted for prognostic factors. Patient safety factors may have an important role. Registration number: NCT02179112 (http://www.clinicaltrials.gov)

    Search for eccentric black hole coalescences during the third observing run of LIGO and Virgo

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    Despite the growing number of confident binary black hole coalescences observed through gravitational waves so far, the astrophysical origin of these binaries remains uncertain. Orbital eccentricity is one of the clearest tracers of binary formation channels. Identifying binary eccentricity, however, remains challenging due to the limited availability of gravitational waveforms that include effects of eccentricity. Here, we present observational results for a waveform-independent search sensitive to eccentric black hole coalescences, covering the third observing run (O3) of the LIGO and Virgo detectors. We identified no new high-significance candidates beyond those that were already identified with searches focusing on quasi-circular binaries. We determine the sensitivity of our search to high-mass (total mass M&gt;70 M⊙) binaries covering eccentricities up to 0.3 at 15 Hz orbital frequency, and use this to compare model predictions to search results. Assuming all detections are indeed quasi-circular, for our fiducial population model, we place an upper limit for the merger rate density of high-mass binaries with eccentricities 0&lt;e≤0.3 at 0.33 Gpc−3 yr−1 at 90\% confidence level

    A first update on mapping the human genetic architecture of COVID-19

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    A Solidly Mounted Resonator With CMOS-Fabricated Acoustic Mirror For Low-Cost Air Quality Monitoring

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    This work presents a novel Solidly Mounted Resonator (SMR) device for use in a portable, low-cost and low power air quality monitor. The acoustic mirror, an essential part of the SMR device for energy confinement, is fabricated within a CMOS process, and advances upon current acoustic device technology. This CMOS-fabricated acoustic mirror will enable the device to be monolithically integrated and fabricated in high volume with reduced post-processing steps compared to the state-of-the-art acoustic based sensors. The CMOS-fabricated acoustic mirror demonstrated good reflectivity with a high quality factor of 500. Experimental results on particulate matter sensing with the CMOS based SMR sensor showed a response of 117 kHz/ng when detecting fine particles (<1 mu m)

    Search for Eccentric Black Hole Coalescences during the Third Observing Run of LIGO and Virgo

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    International audienceDespite the growing number of confident binary black hole coalescences observed through gravitational waves so far, the astrophysical origin of these binaries remains uncertain. Orbital eccentricity is one of the clearest tracers of binary formation channels. Identifying binary eccentricity, however, remains challenging due to the limited availability of gravitational waveforms that include effects of eccentricity. Here, we present observational results for a waveform-independent search sensitive to eccentric black hole coalescences, covering the third observing run (O3) of the LIGO and Virgo detectors. We identified no new high-significance candidates beyond those that were already identified with searches focusing on quasi-circular binaries. We determine the sensitivity of our search to high-mass (total mass M>70M>70MM_\odot) binaries covering eccentricities up to 0.3 at 15 Hz orbital frequency, and use this to compare model predictions to search results. Assuming all detections are indeed quasi-circular, for our fiducial population model, we place an upper limit for the merger rate density of high-mass binaries with eccentricities 0<e0.30 < e \leq 0.3 at 0.330.33 Gpc3^{-3} yr1^{-1} at 90% confidence level

    Search for Eccentric Black Hole Coalescences during the Third Observing Run of LIGO and Virgo

    No full text
    International audienceDespite the growing number of confident binary black hole coalescences observed through gravitational waves so far, the astrophysical origin of these binaries remains uncertain. Orbital eccentricity is one of the clearest tracers of binary formation channels. Identifying binary eccentricity, however, remains challenging due to the limited availability of gravitational waveforms that include effects of eccentricity. Here, we present observational results for a waveform-independent search sensitive to eccentric black hole coalescences, covering the third observing run (O3) of the LIGO and Virgo detectors. We identified no new high-significance candidates beyond those that were already identified with searches focusing on quasi-circular binaries. We determine the sensitivity of our search to high-mass (total mass M>70M>70MM_\odot) binaries covering eccentricities up to 0.3 at 15 Hz orbital frequency, and use this to compare model predictions to search results. Assuming all detections are indeed quasi-circular, for our fiducial population model, we place an upper limit for the merger rate density of high-mass binaries with eccentricities 0<e0.30 < e \leq 0.3 at 0.330.33 Gpc3^{-3} yr1^{-1} at 90% confidence level
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