284 research outputs found

    Video Tester -- A multiple-metric framework for video quality assessment over IP networks

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    This paper presents an extensible and reusable framework which addresses the problem of video quality assessment over IP networks. The proposed tool (referred to as Video-Tester) supports raw uncompressed video encoding and decoding. It also includes different video over IP transmission methods (i.e.: RTP over UDP unicast and multicast, as well as RTP over TCP). In addition, it is furnished with a rich set of offline analysis capabilities. Video-Tester analysis includes QoS and bitstream parameters estimation (i.e.: bandwidth, packet inter-arrival time, jitter and loss rate, as well as GOP size and I-frame loss rate). Our design facilitates the integration of virtually any existing video quality metric thanks to the adopted Python-based modular approach. Video-Tester currently provides PSNR, SSIM, ITU-T G.1070 video quality metric, DIV and PSNR-based MOS estimations. In order to promote its use and extension, Video-Tester is open and publicly available.Comment: 5 pages, 5 figures. For the Google Code project, see http://video-tester.googlecode.com

    Optimized LTE Data Transmission Procedures for IoT: Device Side Energy Consumption Analysis

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    The efficient deployment of Internet of Things (IoT) over cellular networks, such as Long Term Evolution (LTE) or the next generation 5G, entails several challenges. For massive IoT, reducing the energy consumption on the device side becomes essential. One of the main characteristics of massive IoT is small data transmissions. To improve the support of them, the 3GPP has included two novel optimizations in LTE: one of them based on the Control Plane (CP), and the other on the User Plane (UP). In this paper, we analyze the average energy consumption per data packet using these two optimizations compared to conventional LTE Service Request procedure. We propose an analytical model to calculate the energy consumption for each procedure based on a Markov chain. In the considered scenario, for large and small Inter-Arrival Times (IATs), the results of the three procedures are similar. While for medium IATs CP reduces the energy consumption per packet up to 87% due to its connection release optimization

    Analytic Analysis of Narrowband IoT Coverage Enhancement Approaches

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    The introduction of Narrowband Internet of Things (NB-IoT) as a cellular IoT technology aims to support massive Machine-Type Communications applications. These applications are characterized by massive connections from a large number of low-complexity and low-power devices. One of the goals of NB-IoT is to improve coverage extension beyond existing cellular technologies. In order to do that, NB-IoT introduces transmission repetitions and different bandwidth allocation configurations in uplink. These new transmission approaches yield many transmission options in uplink. In this paper, we propose analytical expressions that describe the influence of these new approaches in the transmission. Our analysis is based on the Shannon theorem. The transmission is studied in terms of the required Signal to Noise Ratio, bandwidth utilization, and energy per transmitted bit. Additionally, we propose an uplink link adaptation algorithm that contemplates these new transmission approaches. The conducted evaluation summarizes the influence of these approaches. Furthermore, we present the resulting uplink link adaptation from our proposed algorithm sweeping the device's coverage.Comment: Accepted in the 2018 Global IoT Summit (GIoTS) conferenc

    Label-Free Plasmonic Biosensor for Rapid, Quantitative, and Highly Sensitive COVID-19 Serology: Implementation and Clinical Validation

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    COVID-19; Biosensor plasmónico; SerologíaCOVID-19; Biosensor plasmònic; SerologiaCOVID-19; Plasmonic biosensor; SerologySerological tests are essential for the control and management of COVID-19 pandemic (diagnostics and surveillance, and epidemiological and immunity studies). We introduce a direct serological biosensor assay employing proprietary technology based on plasmonics, which offers rapid (<15 min) identification and quantification of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibodies in clinical samples, without signal amplification. The portable plasmonic device employs a custom-designed multiantigen (RBD peptide and N protein) sensor biochip and reaches detection limits in the low ng mL–1 range employing polyclonal antibodies. It has also been implemented employing the WHO-approved anti-SARS-CoV-2 immunoglobulin standard. A clinical validation with COVID-19 positive and negative samples (n = 120) demonstrates its excellent diagnostic sensitivity (99%) and specificity (100%). This positions our biosensor as an accurate and easy-to-use diagnostics tool for rapid and reliable COVID-19 serology to be employed both at laboratory and decentralized settings for the disease management and for the evaluation of immunological status during vaccination or treatment.ICN2 and UVE acknowledge financial support from H2020 Research and Innovation Programme of the European Commission (H202-SC1-PHE-Coronavirus-2020, CONVAT Project, No. 101003544). The ICN2 is funded by the CERCA program/Generalitat de Catalunya and supported by the Severo Ochoa Centres of Excellence program funded by the Spanish Research Agency (AEI, grant no. SEV-2017-0706). ICN2 group is very grateful to EPI Industries (Barcelona, Spain) for its kind donation supporting our research in COVID-19. O.C.-L. acknowledges the economic support from the Spanish Ministry of Science and Innovation and the Spanish Research Agency and the European Social Fund (ESF) (ref. BES-2017-080527) linked to the TEC 2016-78515-R project Predict. A part of the work was supported by the European Virus Archive GLOBAL (EVA-GLOBAL) project that has received funding from the EU Horizon 2020 (grant agreement No. 871029). A.T. and L.F.-B. acknowledge financial support from GENCAT-DGRIS COVID. We are indebted to all the patients who accepted to participate contributing to science advancement. We are indebted to the HCB-IDIBAPS Biobank for the human samples and data procurement and to the Fundació Glòria Soler for its support to the COVIDBANK collection. We thank the IDIBAPS Biobank for its valuable contribution to sample processing and storage. The authors acknowledge the EU Horizon 2020 Program under grant agreement no. 644956 (RAIS project) for funding the Hospital Vall d’Hebron Biobank. The VHIR-HUVH is supported by Plan Nacional de I + D + i 2013-2016 and ISCIII-Ministerio de Ciencia e Innovación, and Spanish Network for Research in Infectious Diseases (REIPI RD16/0016/0003)─cofinanced by European Development Regional Fund “A way to achieve Europe,” Operative program Intelligent Growth 2014. Part of the samples and data from patients included in this study were provided by the Vall d’Hebron University Hospital Biobank (PT17/0015/0047), integrated in the Spanish National Biobanks Network, and they were processed following standard operating procedures with the appropriate approval of the Ethical and Scientific Committee. The authors kindly appreciate the generous donation of samples and clinical data of the donors of the Sepsis Bank of HUVH Biobank and COVID-19 patients attended at HUVH

    Epidemiology of Immune-Mediated Glomerulopathies before and after SARS-CoV-2 Vaccination: A Tertiary Referral Hospital Experience

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    SARS-CoV-2; Immune-mediated glomerulopathy; VaccineSARS-CoV-2; GlomerulopatĂ­a inmunomediada; VacunaSARS-CoV-2; Glomerulopatia immunomediada; VacunaBackground: Vaccination is a known trigger for the appearance of immune-mediated glomerulopathies (IMG). The appearance of IMG after SARS-CoV-2 vaccination with suspected causality has been described. Our aim is to analyze the incidence of IMG flares before and after SARS-CoV-2 vaccination in our center. Methods: All persons with native kidney biopsy (KB) from January 2019 to March 2022 in our center were included in the study. We compared the incidence of IMG before and after the start of vaccination. We also collected information about whether the patients had received a SARS-CoV-2 vaccine or have suffered from COVID in the six weeks before the IMG. We also evaluated the analytical characteristics of the outbreaks. Results: A total of 386 KB were studied. Of them, 86/218 (39.4%) were IMG performed pre- and 85/168 (50.6%) post-SV (029). The incidence of idiopathic nephrotic syndrome (INS), studied separately, was also significantly increased post-vaccination (n = 18 (10.7%)) compared to pre-vaccination (n = 11 (5%)) (p = 0.036). There were no differences in the incidence of vasculitis or IgA nephropathy. Up to 17 (20%) flares occurred 6 weeks before SARS-CoV-2 vaccination and only 2 (2.4%) within the first 6 weeks after SARS-CoV-2 infection. Within those 17 flares, the most common diagnosis was IgAN (n = 5 (29.4%)); a total of 14 (82.4%) received an mRNA vaccine and 9 (52.9%) took place after the 1st vaccine dose. There were 13 cases of minimal change disease (MCD) with debut/recurrence pre-SV and 20 MCD with debut/recurrence post-SV (p = 0.002). Conclusions: The incidence of IMG, INS and MCD flares in our center increased significantly after SARS-CoV-2 vaccination. Importantly, 20% of IMG flares took place within the first 6 weeks after receiving a vaccine dose, with the first dose being the riskiest one and IgAN the most frequent diagnosis.This research was funded by ISCIIII-FEDER and ISCIII-RETICS REDinREN, grant numbers PI17/00257, PI21/01292, RICORS RD21/0005/0016, MaratĂł TV3 2020 421/C/2020, MaratĂł TV3 2021 215/C/2021, and ERA-PerMed-JTC 2022 (ONAKI-ICI AC22/00029)

    Full breastfeeding and paediatric cancer

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    Aim: It has been suggested that there is an inverse association between breastfeeding and the risk of childhood cancer. We investigated the association between full breastfeeding and paediatric cancer (PC) in a case control study in Spain. Methods: Maternal reports of full breastfeeding, collected through personal interviews using the Paediatric Environmental History, were compared among 187 children 6 months of age or older who had PC and 187 age-matched control siblings. Results: The mean duration of full breastfeeding for cases were 8.43 and 11.25 weeks for controls. Cases had been significantly more often bottle-fed than controls (odds ratio (OR) 1.8; 95% confidence interval (CI) 1.1-2.8). Cases were significantly less breastfed for at least 2 months (OR 0.5; 95% CI 0.3-0.8), for at least 4 months (OR 0.5; 95% CI 0.3-0.8), and for 24 weeks or more (OR 0.5; 95% CI 0.2-0.9). Conclusions: Breastfeeding was inversely associated with PC, the protection increasing with the duration of full breastfeeding. Additional research on possible mechanisms of this association may be warranted. Meanwhile, breastfeeding should be encouraged among mothers

    New GOLD classification: longitudinal data on group assignment

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    Rationale: Little is known about the longitudinal changes associated with using the 2013 update of the multidimensional GOLD strategy for chronic obstructive pulmonary disease (COPD). Objective: To determine the COPD patient distribution of the new GOLD proposal and evaluate how this classification changes over one year compared with the previous GOLD staging based on spirometry only. Methods: We analyzed data from the CHAIN study, a multicenter observational Spanish cohort of COPD patients who are monitored annually. Categories were defined according to the proposed GOLD: FEV1%, mMRC dyspnea, COPD Assessment Test (CAT), Clinical COPD Questionnaire (CCQ), and exacerbations-hospitalizations. One-year follow-up information was available for all variables except CCQ data. Results: At baseline, 828 stable COPD patients were evaluated. On the basis of mMRC dyspnea versus CAT, the patients were distributed as follows: 38.2% vs. 27.2% in group A, 17.6% vs. 28.3% in group B, 15.8% vs. 12.9% in group C, and 28.4% vs. 31.6% in group D. Information was available for 526 patients at one year: 64.2% of patients remained in the same group but groups C and D show different degrees of variability. The annual progression by group was mainly associated with one-year changes in CAT scores (RR, 1.138; 95%CI: 1.074-1.206) and BODE index values (RR, 2.012; 95%CI: 1.487-2.722). Conclusions: In the new GOLD grading classification, the type of tool used to determine the level of symptoms can substantially alter the group assignment. A change in category after one year was associated with longitudinal changes in the CAT and BODE index
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