Galileo and EGNOS as an asset for UTM safety and security

GAUSS (Galileo-EGNOS as an Asset for UTM Safety and Security) is a H2020 project1 that aims at designing and developing high performance positioning systems for drones within the U-Space framework focusing on UAS (Unmanned Aircraft System) VLL (Very Low Level) operations. The key element within GAUSS is the integration and exploitation of Galileo and EGNOS exceptional features in terms of accuracy, integrity and security, which will be key assets for the safety of current and future drone operations. More concretely, high accuracy, authentication, precise timing (among others) are key GNSS (Global Navigation Satellite System) enablers of future integrated drone operations under UTM (UAS Traffic Management) operations, which in Europe will be deployed under U-Space [1]. The U-Space concept helps control, manage and integrate all UAS in the VLL airspace to ensure the security and efficiency of UAS operations. GAUSS will enable not only safe, timely and efficient operations but also coordination among a higher number of RPAS (Remotely Piloted Aircraft System) in the air with the appropriate levels of security, as it will improve anti-jamming and anti-spoofing capabilities through a multi-frequency and multi-constellation approach and Galileo authentication operations. The GAUSS system will be validated with two field trials in two different UTM real scenarios (in-land and sea) with the operation of a minimum of four UTM coordinated UAS from different types (fixed and rotary wing), manoeuvrability and EASA (European Aviation Safety Agency) operational categories. The outcome of the project will consist of Galileo-EGNOS based technological solutions to enhance safety and security levels in both, current UAS and future UTM operations. Increased levels of efficiency, reliability, safety, and security in UAS operations are key enabling features to foster the EU UAS regulation, market development and full acceptance by the society.Peer ReviewedPostprint (author's final draft

Risk factors for ischaemic heart disease in a Cretan rural population: a twelve year follow-up study

<p>Abstract</p> <p>Background</p> <p>Crete has been of great epidemiological interest ever since the publication of the Seven Countries Study. In 1988 a well-defined area of rural Crete was studied, with only scarce signs of coronary heart disease (CHD) despite the unfavorable risk profile. The same population was re-examined twelve years later aiming to describe the trends of CHD risk factors over time and discuss some key points on the natural course of coronary heart disease in a rural population of Crete.</p> <p>Methods and Results</p> <p>We re-examined 200 subjects (80.7% of those still living in the area, 62.4 ± 17.0 years old). The prevalence of risk factors for CHD was high with 65.9% of men and 65.1% of women being hypertensive, 14.3% of men and 16.5% of women being diabetic, 44% of men being active smokers and more than 40% of both sexes having hyperlipidaemia. Accordingly, 77.5% of the population had a calculated Framingham Risk Score (FRS) ≥ 15%, significantly higher compared to baseline (p < 0.001). The overall occurrence rate for CHD events was calculated at 7.1 per 1000 person-years (95% confidence interval: 6.8–7.3).</p> <p>Conclusion</p> <p>The study confirms the unfavorable risk factor profile of a well defined rural population in Crete. Its actual effect on the observed incidence of coronary events in Cretans remains yet to be defined.</p

Study of metal / silicon carbide interfaces with surface sensitive techniques

Silicon carbide (SiC) single crystals are very important for numerous high temperature microelectronic devices. Industrial production of such devices takes advantage of the superior properties that metal/SiC contacts can achieve, like the electrical behavior (Schottky barrier) and their thermal stability. In the present work, we studied the early stages of metal/SiC interface formation in UHV conditions and at room temperature. Additionally, we studied the stability of the contacts at high temperature conditions. For this purpose, we developed ultrathin metallic films of Re, Er and Cu on both polar surfaces (Si-face or (0001) and C-face or (000-1)) of n-type hexagonal single crystal 6H-SiC. The resulting contacts were heated afterwards up to 1000K. Surface sensitive techniques were used for data collection, such as X-ray Photoelectron and Auger Electron Spectroscopy (XPS/XAES), Ultraviolet Photoelectron Spectroscopy (UPS), Low Energy Electron Diffraction (LEED) and Work Function (WF) measurements (Kelvin Probe technique). Furthermore, the height of the interfacial Schottky barrier and its behavior upon annealing were obtained from the XPS data. Based upon our experimental data, we reached the following conclusions: The Re/6H-SiC{0001} contact was found to be appropriate for use in microelectronic devices that require ohmic contacts consisting of materials with an absolute stability of structural and electronic properties at high temperature conditions, given that the Re/SiC Schottky barrier height is small and Re metallic films are particularly stable at high temperatures. Ix The extended silicide phase and the existence of low Schottky barrier height known from Er/Si contacts was not observed in the Er/6H-SiC{0001} contact, which was found to have a good and stable rectifying behavior. The Er film demonstrated structural stability at high temperatures. Possible use of the Er/SiC contact for microelectronic devices, that require Schottky barrier thermal stability along with the existence of only traces of some silicide interaction at the interface, is considered promising. It was also found that oxygen might play an important role in the Er/SiC interfacial behavior. Finally, for Cu/6H-SiC{0001} the conclusions were correspondingly positive: the electrical behavior of the Cu/SiC contact was found to be rectifying and relatively stable at high temperatures. Considering that SiC is well known as a very good thermal conductor (just like copper), the Cu/SiC contact could meet the standards in a lot of applications in power microelectronic devices.Οι μονοκρύσταλλοι ανθρακοπυριτίου (SiC) παρουσιάζουν μεγάλο ενδιαφέρον χάρις στις ποικίλες εφαρμογές τους, κυρίως σε μικροηλεκτρονικές διατάξεις υψηλών θερμοκρασιών. Ιδιαίτερα σημαντικό ρόλο στη δημιουργία τέτοιων διατάξεων έχουν οι επαφές μετάλλου/ανθρακοπυριτίου, σε σχέση με την ηλεκτρική συμπεριφορά (φράγμα Schottky) και τη σταθερότητά τους στη θέρμανση. Στο πλαίσιο της παρούσας εργασίας μελετήθηκαν τα πρώιμα στάδια ανάπτυξης της διεπιφάνειας μετάλλου/SiC σε περιβάλλον υπερυψηλού κενού (UHV) και θερμοκρασία δωματίου καθώς και η σταθερότητα της επαφής κατά τη θέρμανση σε υψηλές θερμοκρασίες. Αναπτύχθηκαν υπέρλεπτα μεταλλικά υμένια Re, Er και Cu πάνω και στις δύο πολικές επιφάνειες (Si-face ή (0001) και C-face ή (000-1)) των μονοκρυστάλλων εξαγωνικού ανθρακοπυριτίου (6H-SiC) τύπου-n που χρησιμοποιήθηκαν ως υπόστρωμα. Οι επαφές αυτές στη συνέχεια θερμαίνονταν μέχρι τους 1000Κ. Η μελέτη έγινε με επιφανειακά ευαίσθητες τεχνικές, όπως οι Φασματοσκοπίες Φωτοηλεκτρονίων και Ηλεκτρονίων Auger Ακτίνων-Χ, (XPS/XAES) και Φωτοηλεκτρονίων Υπεριώδους (UPS), η Περίθλαση Ηλεκτρονίων Χαμηλής Ενέργειας (LEED) και η μέτρηση μεταβολών του Έργου Εξόδου της επιφάνειας (WF / Kelvin Probe). Επιπλέον, το ύψος του διεπιφανειακού φράγματος Schottky και η συμπεριφορά του κατά τη θέρμανση μελετήθηκαν βάσει δεδομένων από την τεχνική XPS. Με βάση τα πειραματικά αποτελέσματα, τα συμπεράσματα στα οποία καταλήξαμε καταδεικνύουν ότι: Το Re είναι ιδανικό για ωμικές επαφές Re/6H-SiC{0001} σε μικροηλεκτρονικές διατάξεις που απαιτούν απόλυτη σταθερότητα δομικών και ηλεκτρικών χαρακτηριστικών σε αρκετά υψηλές θερμοκρασίες, δεδομένου ότι παρουσιάζει μικρό φράγμα Schottky και το μεταλλικό υμένιο αποδεικνύεται ιδιαίτερα σταθερό στις υψηλές θερμοκρασίες. Η επαφή Er/6H-SiC{0001} δεν παρουσίασε την εκτεταμένη πυριτιδιακή φάση που έχει αναφερθεί για τις επαφές Er/Si και το ιδιαίτερα χαμηλό φράγμα Schottky, όμως παρουσίασε καλή ανορθωτική συμπεριφορά και δομική σταθερότητα του υμενίου Er. Αυτό ανοίγει το δρόμο και σε εφαρμογές που εκμεταλλεύονται τον σταθερό ανορθωτικό χαρακτήρα της επαφής σε συνδυασμό με την εμφάνιση μικρής έκτασης πυριτιδιακής αλληλεπίδρασης στη διεπιφάνεια. Εδώ σημαντικό ρόλο φαίνεται να παίζει και η αναπόφευκτη παρουσία αυξημένης ποσότητας οξυγόνου στο υμένιο. Τέλος, για την επαφή Cu/6H-SiC{0001}, τα συμπεράσματα είναι αντιστοίχως θετικά: Η επαφή Cu/6H-SiC{0001} προκύπτει ανορθωτική και σχετικά σταθερή στις υψηλές θερμοκρασίες και, δεδομένου ότι το SiC χαρακτηρίζεται από αρκετά καλή θερμική αγωγιμότητα όπως και ο χαλκός, μπορεί εμφανώς να εξυπηρετήσει ανάγκες σε ανορθωτικές διατάξεις κυκλωμάτων μεταφοράς ισχύος, όπου απαιτείται σταθερότητα ηλεκτρικών χαρακτηριστικών και αντοχή σε υψηλές θερμοκρασίες

EVALUATION OF GREEK HIGH SCHOOL TEACHERS&apos; KNOWLEDGE IN BASIC LIFE SUPPORT, AUTOMATED EXTERNAL DEFIBRILLATION, AND FOREIGN BODY AIRWAY OBSTRUCTION: IMPLICATIONS FOR NURSING INTERVENTIONS

Introduction: The aim of this study was to evaluate the theoretic knowledge of high school teachers regarding cardiopulmonary resuscitation, automated external defibrillation, and foreign body airway obstruction. Methods: Three hundred ten respondents were tested prospectively by use of a scoring system. Data were obtained by use of a questionnaire that included 24 questions. Data were collected between April 9 and June 16, 2009. Results: Only 21.03% of the teachers had ever participated in life support courses, and most of them did not possess adequate theoretic knowledge in the management of adult cardiac arrest or foreign body airway obstruction. As the age of the teachers increases, the ratio of correct answers decreases. Life support course attendance has a positive effect on their theoretic knowledge. The majority of the teachers would welcome an emergency nurse to educate them and their students on basic life support and foreign body airway obstruction. Discussion: This study shows that most of the respondents had a mediocre level of knowledge in basic life support, automated external defibrillation, and foreign body airway obstruction. Given that emergency nurses regularly practice resuscitation in the emergency department in which they are working, they have the motivation to be kept updated with the current guidelines on resuscitation, because guidelines on resuscitation are revised every 5 years. Teachers, on the other hand, are less motivated to be kept updated; thus emergency nurses may be the key component in educating teachers and school students. Therefore we believe that emergency nurses should take on the responsibility and act as school educators regarding cardiopulmonary resuscitation

Abdominal compressions do not achieve similar survival rates compared with chest compressions: an experimental study

Aim: The aim of this study is to investigate whether abdominal compression cardiopulmonary resuscitation (CPR) would result in similar survival rates and neurologic outcome than chest compression CPR in a swine model of cardiac arrest. Materials and methods: Forty Landrace/Large White piglets were randomized into 2 groups: group A (n = 20) was resuscitated using chest compression CPR, and group B (n = 20) was resuscitated with abdominal compression CPR. Ventricular fibrillation was induced with a pacemaker catheter, and animals were left untreated for 8 minutes. Abdominal and chest compressions were applied with a mechanical compressor. Defibrillation was then attempted. Results: Neuron-specific enolase and S-100 levels were significantly higher in group B. Ten animals survived for 24 hours in group A in contrast to only 3 animals in group B (P &lt; .05). Neurologic alertness score was worse in group B compared with group A. Conclusion: Abdominal compression CPR does not improve survival and neurologic outcome in this swine model of cardiac arrest and CPR. (C) 2011 Elsevier Inc. All rights reserved

Galileo and EGNOS as an asset for UTM safety and security

GAUSS (Galileo-EGNOS as an Asset for UTM Safety and Security) is a H2020 project1 that aims at designing and developing high performance positioning systems for drones within the U-Space framework focusing on UAS (Unmanned Aircraft System) VLL (Very Low Level) operations. The key element within GAUSS is the integration and exploitation of Galileo and EGNOS exceptional features in terms of accuracy, integrity and security, which will be key assets for the safety of current and future drone operations. More concretely, high accuracy, authentication, precise timing (among others) are key GNSS (Global Navigation Satellite System) enablers of future integrated drone operations under UTM (UAS Traffic Management) operations, which in Europe will be deployed under U-Space [1]. The U-Space concept helps control, manage and integrate all UAS in the VLL airspace to ensure the security and efficiency of UAS operations. GAUSS will enable not only safe, timely and efficient operations but also coordination among a higher number of RPAS (Remotely Piloted Aircraft System) in the air with the appropriate levels of security, as it will improve anti-jamming and anti-spoofing capabilities through a multi-frequency and multi-constellation approach and Galileo authentication operations. The GAUSS system will be validated with two field trials in two different UTM real scenarios (in-land and sea) with the operation of a minimum of four UTM coordinated UAS from different types (fixed and rotary wing), manoeuvrability and EASA (European Aviation Safety Agency) operational categories. The outcome of the project will consist of Galileo-EGNOS based technological solutions to enhance safety and security levels in both, current UAS and future UTM operations. Increased levels of efficiency, reliability, safety, and security in UAS operations are key enabling features to foster the EU UAS regulation, market development and full acceptance by the society.Peer Reviewe

Galileo and EGNOS as an asset for UTM safety and security

Trabajo presentado en la 25th Ka and Broadband Communications Conference, celebrada en Sorrento (Italia), del 30 de septiembre al 2 de noviembre de 2019GAUSS (Galileo-EGNOS as an Asset for UTM Safety and Security) is a H2020 project1 that aims at designing and developing high performance positioning systems for drones within the U-Space framework focusing on UAS (Unmanned Aircraft System) VLL (Very Low Level) operations. The key element within GAUSS is the integration and exploitation of Galileo and EGNOS exceptional features in terms of accuracy, integrity and security, which will be key assets for the safety of current and future drone operations. More concretely, high accuracy, authentication, precise timing (among others) are key GNSS (Global Navigation Satellite System) enablers of future integrated drone operations under UTM (UAS Traffic Management) operations, which in Europe will be deployed under U-Space [1]. The U-Space concept helps control, manage and integrate all UAS in the VLL airspace to ensure the security and efficiency of UAS operations. GAUSS will enable not only safe, timely and efficient operations but also coordination among a higher number of RPAS (Remotely Piloted Aircraft System) in the air with the appropriate levels of security, as it will improve anti-jamming and anti-spoofing capabilities through a multi-frequency and multi-constellation approach and Galileo authentication operations. The GAUSS system will be validated with two field trials in two different UTM real scenarios (in-land and sea) with the operation of a minimum of four UTM coordinated UAS from different types (fixed and rotary wing), manoeuvrability and EASA (European Aviation Safety Agency) operational categories. The outcome of the project will consist of Galileo-EGNOS based technological solutions to enhance safety and security levels in both, current UAS and future UTM operations. Increased levels of efficiency, reliability, safety, and security in UAS operations are key enabling features to foster the EU UAS regulation, market development and full acceptance by the society.This project receives funding from the EU H2020 Research & Innovation Programme under grant agreement No 77629

Platelet-rich Plasma and Mesenchymal Stem Cells Local Infiltration Promote Functional Recovery and Histological Repair of Experimentally Transected Sciatic Nerves in Rats

Introduction Platelet-rich plasma (PRP) products and mesenchymal stem cells (MSCs) seem to have a significant potential as neurogenic therapeutic modulator systems. This study aimed to investigate such biological blood derivatives that could enhance nerve regeneration when applied locally in the primary repair of peripheral nerve transection of an experimental rat model. Methods A total of 42 two-month-old male Wistar rats were divided into three “treatment” groups (control, PRP, and MSCs). All the subjects were operated under anesthesia, and the surgical site was infiltrated with either normal saline, PRP derived from the animal’s peripheral blood, or MSCs derived from the animal’s femoral bone marrow. All three groups were also sub-divided into two sub-groups based on the post-operative administration of Non-steroidal anti-inflammatory drugs (NSAIDs) or not in order to evaluate the effect of NSAIDs on the final outcome. Three months post-surgery, electromyography evaluation of both hind limbs (right operated and left non-operated) was performed. The animals were euthanized, and nerve repair specimens were prepared for histology. Results PRP group had a significant effect (p&lt;0.05) on the sciatic nerve repair when compared with the control group, whereas the MSC group had a positive effect but was not statistically significant (p=0.2). The number of counted neural axons at the area distal to the nerve repair site were significantly repetitive (p&lt;0.05) in both the PRP and MSC groups when compared with the control group. Conclusions Both PRP and MSCs appear to play an essential role in the enhancement of nerve repair in terms of functionality and histology. MSCs group demonstrated a positive effect, whereas the PRP group showed statistically significant better results

Evaluation of Femoral Bone Fracture Healing in Rats by the Modal Damping Factor and Its Correlation With Peripheral Quantitative Computed Tomography

Introduction Monitoring the progress of fracture healing is essential in order to establish the appropriate timing that ensures adequate bone strength for weight-bearing. In the present experimental study on a rat model of femoral fracture healing, the measurement of bone density and strength by peripheral quantitative computerized tomography (pQCT) was correlated with the modal damping factor (MDF) method. Methods Four groups of 12 male six-month-old Wistar rats each were anesthetized and submitted to baseline femoral pQCT and MDF scanning, followed by aseptic midshaft osteotomy of the right femur which was fixed by a locking intramedullary nail technique. The animals were left to recover and re-scanned following euthanasia of each group after six, eight, 10, and 12 weeks, respectively. The parameters measured by the pQCT method were total bone mineral density (BMD) and polar strength strain index (SSIp). Results Fracture healing progressed over time and at 12 weeks post-osteotomy there was no statistically significant difference between the osteotomized right and the control left femurs regarding MDF, BMD, and SSIp measurements. The highest correlations for the osteotomized femurs were observed between MDF and BMD (r = -0.647, P = 0.043), and between MDF and SSIp (r = -0.350, P = 0.321), at 10 weeks postoperatively. The high to moderate correlations between MDF and BMD, and between MDF and SSIp respectively, support the validity of MDF in assessing fracture healing. Conclusions Based on our findings in this fracture healing animal model, the results from the MDF method are reliable and correlate highly with the total BMD and moderately with the SSI polar values obtained by the pQCT method of bone quality measurement. Further studies are needed which may additionally support that the MDF method can be an attractive portable alternative to monitor fracture healing in the community