29 research outputs found
Author Correction: RNAs coordinate nuclear envelope assembly and DNA replication through ELYS recruitment to chromatin
No full textIn the original version of this Article, the affiliation details for Antoine Aze, Michalis Fragkos, Stéphane Bocquet, Julien Cau and Marcel Méchali incorrectly omitted ‘CNRS and the University of Montpellier’. This has now been corrected in both the PDF and HTML versions of the Article.</jats:p
V2X Communication over Cellular Networks: Capabilities and Challenges
No full textVehicular communications is expected to be one of the key applications for cellular networks during the following decades. Key international organizations have already described in detail a number of related use cases, along with their requirements. This article provides a comprehensive analysis of these use cases and a harmonized view of the requirements for the latest and most advanced autonomous driving applications. It also investigates the extent of support that 4G and 5G networks can offer to these use cases in terms of delay and spectrum needs. The paper identifies open issues and discusses trends and potential solutions
Exploiting voice recognition techniques to provide farm and greenhouse monitoring for elderly or disabled farmers, over Wi-Fi and LoRa interfaces
No full textΧρήση του Φάσματος Συχνοτήτων 70-500GHz στις δορυφορικές επικοινωνίες
No full textΣτα πλαίσια αυτής της διπλωματικής εργασίας έγινε μία προσπάθεια να επικεντρώσουμε το ενδιαφέρον μας στις συχνότητες που αφορούν τις δορυφορικές επικοινωνίες. Στο πρώτο κεφάλαιο γίνεται μία ιστορική αναδρομή στις δορυφορικές επικοινωνίες και σε θέματα που αφορούν τη δομή τους, την αρχιτεκτονική τους, τις τροχιές, τις υπηρεσίες και τις εφαρμογές τους. Στο δεύτερο κεφάλαιο γίνεται μία παρουσίαση των δορυφορικών επικοινωνιών με τη χρήση συχνοτήτων σε TeraHertz τιμές. Παράλληλα, αναφερόμαστε στα κίνητρα για τη χρήση των TeraHertz συχνοτήτων καθώς και στην ατμοσφαιρική απορρόφηση σε αυτές τις συχνότητες. Στο τρίτο κεφάλαιο αναφερόμαστε σε μήκη κύματος της τάξης των mm και στο μοντέλο καναλιού σε μήκη κύματος mm. Ταυτόχρονα, παρουσιάζονται δύο εφαρμογές γι’ αυτά τα μήκη κύματος (mmMAGIC Project και mmWave Backhaul και Fronthaul). Τέλος, στο τέταρτο κεφάλαιο εκθέτουμε μία σειρά από συμπεράσματα που αφορούν τη χρήση υπερυψηλών συχνοτήτων στις δορυφορικές επικοινωνίες.In the context of this dissertation, an attempt was made to focus our attention on the frequencies related to satellite communications. The first chapter provides a historical overview of satellite communications and issues related to their structure, architecture, trajectories, services and applications. The second chapter presents a presentation of satellite communications using frequencies in TeraHertz values. At the same time, we refer to the incentives for the use of TeraHertz frequencies as well as to the atmospheric absorption at these frequencies. In the third chapter we refer to wavelengths of the order of mm and to the channel model in wavelengths of mm. At the same time, two applications are presented for these wavelengths (mmMAGIC Project and mmWave Backhaul and Fronthaul). Finally, in the fourth chapter we present a series of conclusions regarding the use of high frequencies in satellite communications
Treatment of infrainguinal thromboembolic complications during peripheral endovascular procedures with AngioJet rheolytic thrombectomy, intraoperative thrombolysis, and selective stenting
No full textObjectiveThis study investigated the safety and effectiveness of the infrainguinal use of the AngioJet rheolytic mechanical thrombectomy system (Possis Medical, Minneapolis, Minn) for the treatment of acute infrainguinal thromboembolism occurring during lower limb revascularization procedures.MethodsFor the interval between January 2000 and January 2011, our hospital's database was meticulously searched for all patients with acute thromboembolism that occurred during lower limb angioplasty, with or without stenting procedures, who were treated with infrainguinal AngioJet thrombectomy. Baseline patient demographics and procedural details were analyzed. Primary end points included technical success, defined as the complete revascularization of the acutely occluded vessel; clinical success, defined as the absence of death or amputation ≤60 days; and procedure-related complication. Secondary end points included embolized vessel primary patency and overall patient survival.ResultsDuring this 12-year period, 3147 peripheral percutaneous procedures of angioplasty, with or without stenting, were performed in our department. Intraoperative, clinically, and angiographically evident thromboembolism occurred in 18 of 3147 procedures (0.57%), and 14 (77.7%) were managed using the AngioJet thrombectomy system. In total, 22 arteries were treated (13 infrapopliteal, 3 femoropopliteal, and 6 popliteal arteries). All patients had a completion angiogram for the assessment of the runoff vessels' status. Technical and clinical success occurred in 13 of 14 (92.8%). Adjunctive local thrombolysis or clot trapping, or both, with stenting was used in 64.3% and 42.8% of the procedures, respectively. Mean time follow-up was 38.1 ± 49.0 months. The 1-year embolized vessel primary patency rate was 50.9%, and the survival rate was 53.5% up to 11.5 years of follow-up, as estimated by Kaplan-Meier analysis. The 1-year limb salvage rate was 92.3%. There were no procedure-related minor amputations and one (7.1%) procedure-related major above-knee amputation.ConclusionsThe use of AngioJet rheolytic thrombectomy and adjunctive local thrombolysis or stenting, or both, under filter protection, is safe and effective for the management of severe thromboembolic complications occurring in the femoropopliteal and infrapopliteal arteries during peripheral endovascular procedures
Response of the TEROS 12 Soil Moisture Sensor under Different Soils and Variable Electrical Conductivity
No full textIn this work, the performance of the TEROS 12 electromagnetic sensor, which measures volumetric soil water content (θ), bulk soil electrical conductivity (σb), and temperature, is examined for a number of different soils, different θ and different levels of the electrical conductivity of the soil solution (ECW) under laboratory conditions. For the above reason, a prototype device was developed including a low-cost microcontroller and suitable adaptation circuits for the aforementioned sensor. Six characteristic porous media were examined in a θ range from air drying to saturation, while four different solutions of increasing Electrical Conductivity (ECw) from 0.28 dS/m to approximately 10 dS/m were used in four of these porous media. It was found that TEROS 12 apparent dielectric permittivity (εa) readings were lower than that of Topp’s permittivity–water content relationship, especially at higher soil water content values in the coarse porous bodies. The differences are observed in sand (S), sandy loam (SL) and loam (L), at this order. The results suggested that the relationship between experimentally measured soil water content (θm) and εa0.5 was strongly linear (0.869 < R2 < 0.989), but the linearity of the relation θm-εa0.5 decreases with the increase in bulk EC (σb) of the soil. The most accurate results were provided by the multipoint calibration method (CAL), as evaluated with the root mean square error (RMSE). Also, it was found that εa degrades substantially at values of σb less than 2.5 dS/m while εa returns to near 80 at higher values. Regarding the relation εa-σb, it seems that it is strongly linear and that its slope depends on the pore water electrical conductivity (σp) and the soil type
Performance Evaluation of TEROS 10 Sensor in Diverse Substrates and Soils of Different Electrical Conductivity Using Low-Cost Microcontroller Settings
No full textThis study sheds light on the performance of the common high-precision electromagnetic sensor TEROS 10 to estimate volumetric soil water content (θ) from dry to saturation across three different substrates, six different soil types having three different levels of electrical conductivity of soil solutions (ECw), and in liquids with increasing salinity level under laboratory conditions, by using low-cost but accurate experimental IoT hardware arrangements. This performance was evaluated using statistical analysis metrics such as Root Mean Square Error (RMSE). It was found that TEROS 10 performance did not conform to the manufacturer’s specifications throughout the full scale range, although in some cases good water content estimation was provided. Some inconsistencies were identified by applying the manufacturer’s calibration equations, and thus recommendations for improvements are provided, aiming to enhance the sensor’s overall performance. TEROS 10 performance across all six soils and three substrates was improved on average from an RMSE of 0.052 and 0.078 cm3 cm−3, respectively, by using factory-derived calibration, to 0.031 and 0.031 cm3 cm−3 by using the multipoint calibration method (CAL). Furthermore, a linear calibration formula, using Raw output as the predictor variable, was tested and resulted in an RMSE of 0.026 and 0.046 cm3 cm−3 for soils and substrates, respectively
3D laser scanning and digital restoration of an archaeological find
No full textThe current paper demonstrates the digital recreation and 3D printing of a missing fragment of an ancient ceramic pottery following digitization using a three dimensional laser scanning. The resulting pointcloud of the laser scans was treated with a series of advanced software for the creation of surfaces and ultimately for a digital model. An analytical methodology is presented revealing the step by step approach, which is an innovative way of recreating a missing fragment. Such approach aims to demonstrate the level of contribution that the ever evolving computer based technologies and 3D printing could bring to cultural heritage. The reverse engineering method presented for the reconstruction of a ceramic pottery, which is a part of the larger field of digital archaeology, is believed to benefit a variety of interested parties including 3D CAD users and designers, archaeologists and museum curators
3D laser scanning and digital restoration of an archaeological find
No full textThe current paper demonstrates the digital recreation and 3D printing of a missing fragment of an ancient ceramic pottery following digitization using a three dimensional laser scanning. The resulting pointcloud of the laser scans was treated with a series of advanced software for the creation of surfaces and ultimately for a digital model. An analytical methodology is presented revealing the step by step approach, which is an innovative way of recreating a missing fragment. Such approach aims to demonstrate the level of contribution that the ever evolving computer based technologies and 3D printing could bring to cultural heritage. The reverse engineering method presented for the reconstruction of a ceramic pottery, which is a part of the larger field of digital archaeology, is believed to benefit a variety of interested parties including 3D CAD users and designers, archaeologists and museum curators
