260 research outputs found

    Time-varying neutrino mass from a supercooled phase transition: current cosmological constraints and impact on the Ωm\Omega_m-σ8\sigma_8 plane

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    In this paper we investigate a time-varying neutrino mass model, motivated by the mild tension between cosmic microwave background (CMB) measurements of the matter fluctuations and those obtained from low-redshift data. We modify the minimal case of the model proposed by Dvali and Funcke (2016) that predicts late neutrino mass generation in a post-recombination cosmic phase transition, by assuming that neutrino asymmetries allow for the presence of relic neutrinos in the late-time Universe. We show that, if the transition is supercooled, current cosmological data (including CMB temperature, polarization and lensing, baryon acoustic oscillations, and Type Ia supernovae) prefer the scale factor asa_s of the phase transition to be very large, peaking at as∼1a_s\sim 1, and therefore supporting a cosmological scenario in which neutrinos are almost massless until very recent times. We find that in this scenario the cosmological bound on the total sum of the neutrino masses today is significantly weakened compared to the standard case of constant-mass neutrinos, with ∑mν<4.8\sum m_\nu<4.8~eV at 95\% confidence, and in agreement with the model predictions. The main reason for this weaker bound is a large correlation arising between the dark energy and neutrino components in the presence of false vacuum energy that converts into the non-zero neutrino masses after the transition. This result provides new targets for the coming KATRIN and PTOLEMY experiments. We also show that the time-varying neutrino mass model considered here does not provide a clear explanation to the existing cosmological Ωm\Omega_m-σ8\sigma_8 discrepancies.Comment: 13 pages, 13 figures, matches updated version accepted by Physical Review

    Bringing Telemedicine Initiatives into Regular Care: Theoretical Underpinning for User-Centred Design Processes

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    Telemedicine is said to change the way care is delivered. Nevertheless, it still faces barriers to overcome the pilot stage and reach a majority of patients in regular care. Missing consideration of user-centred design processes is one major reason for this development as individuals are a key component for the technology’s success. Therefore, we aim to provide recommendations for a user-centred design process, which is, in turn, crucial to successfully implementing telemedicine innovations. To reach this aim, we identified individual-related barriers for telemedicine with an umbrella review. Furthermore, we related the barriers to the Unified Theory of Acceptance and Use of Technology (UTAUT2) proposed by Venkatesh and colleagues. A theoretical explanation helps to generate a broader understanding of what prevents individual acceptance of telemedicine innovations. The provided recommendations are supposed to support researchers and practitioners planning future telemedicine solutions

    Human Respiration Rate Measurement with High-Speed Digital Fringe Projection Technique

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    This paper proposes a non-contact continuous respiration monitoring method based on Fringe Projection Profilometry (FPP). This method aims to overcome the limitations of traditional intrusive techniques by providing continuous monitoring without interfering with normal breathing. The FPP sensor captures three-dimensional (3D) respiratory motion from the chest wall and abdomen, and the analysis algorithms extract respiratory parameters. The system achieved a high Signal-to-Noise Ratio (SNR) of 37 dB with an ideal sinusoidal respiration signal. Experimental results demonstrated that a mean correlation of 0.95 and a mean Root-Mean-Square Error (RMSE) of 0.11 breaths per minute (bpm) were achieved when comparing to a reference signal obtained from a spirometer

    Chief Digital Officers – Review and Research Agenda

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    The Effect of Deltamethrin-Treated Net Fencing Around Cattle Enclosures on Outdoor-biting Mosquitoes in Kumasi, Ghana.

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    Classic vector control strategies target mosquitoes indoors as the main transmitters of malaria are indoor-biting and -resting mosquitoes. However, the intensive use of insecticide-treated bed-nets (ITNs) and indoor residual spraying have put selective pressure on mosquitoes to adapt in order to obtain human blood meals. Thus, early-evening and outdoor vector activity is becoming an increasing concern. This study assessed the effect of a deltamethrin-treated net (100 mg/m(2)) attached to a one-meter high fence around outdoor cattle enclosures on the number of mosquitoes landing on humans. Mosquitoes were collected from four cattle enclosures: Pen A - with cattle and no net; B - with cattle and protected by an untreated net; C - with cattle and protected by a deltamethrin-treated net; D - no cattle and no net. A total of 3217 culicines and 1017 anophelines were collected, of which 388 were Anopheles gambiae and 629 An. ziemanni. In the absence of cattle nearly 3 times more An. gambiae (p<0.0001) landed on humans. The deltamethrin-treated net significantly reduced (nearly three-fold, p<0.0001) culicine landings inside enclosures. The sporozoite rate of the zoophilic An. ziemanni, known to be a secondary malaria vector, was as high as that of the most competent vector An. gambiae; raising the potential of zoophilic species as secondary malaria vectors. After deployment of the ITNs a deltamethrin persistence of 9 months was observed despite exposure to African weather conditions. The outdoor use of ITNs resulted in a significant reduction of host-seeking culicines inside enclosures. Further studies investigating the effectiveness and spatial repellence of ITNs around other outdoor sites, such as bars and cooking areas, as well as their direct effect on vector-borne disease transmission are needed to evaluate its potential as an appropriate outdoor vector control tool for rural Africa
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