Temperature-Compensated Microstrip Antenna for Ice Measurement and Wireless Sensor Network

RÉSUMÉ L'objectif principal de cette thèse est de concevoir et de développer une technique de compensation de température liée à la fréquence de résonance d'une antenne microruban. Une telle antenne microruban compensée en température, capable de résister à une variation importante de température, est utilisée comme une partie d'un capteur pour mesurer l'épaisseur de la charge de la glace. Les antennes microruban conçues de cette manière sont utilisées dans un réseau de capteurs de température sans fil en relation avec ses applications critiques d'un système de dégivrage d'hélicoptère. Un prototype de réseau de capteurs de température sans fil qui contrôle à distance la mise en marche ou l'arrêt des appareils de chauffage destinés au dégivrage est développé. Parmi toutes les autres antennes, l'antenne microruban est sélectionnée en raison de sa polyvalence. Aussi, sa fréquence de résonance souffre d'un problème de stabilité due à sa susceptibilité à des facteurs externes tels que les fluctuations de température. En plus, sa résonance provoquant une largeur de bande de fréquence étroite ne conduit pas à une solution directement préférée. Pour minimiser l'instabilité de fréquence induite par la température et aussi pour éviter de perdre le signal ou les interférences des canaux adjacents, on a besoin de développer une technique de compensation de température très efficace et pratique. Dans ce travail, une technique de compensation de la température efficace et pratique est conçue pour les antennes microruban. La technique de compensation imagée est supérieure à la technique existante, tant dans sa simplicité que dans sa stabilité en fréquence. A notre, connaissance, rien de semblable n'a été fait auparavant. Pour la première fois, la dépendance de la fréquence de résonance de l'antenne microruban en fonction de la température est étudiée à l'aide d'une formulation mathématique de la déviation de fréquence pour les géométries rectangulaires, circulaires et triangulaires. Le modèle de circuit est adopté pour l'analyse de l'impact de la température sur la fréquence de résonance de l'antenne microruban appropriée pour les procédures de CAO (conception assistée par ordinateur). Les simulations électromagnétiques sur les résultats de la théorie de déviation du modèle de circuit adopté. Les résultats de l'impact de la température sur la dérive de fréquence des antennes microruban résonnant à 2,4 GHz modélisées sur différents substrats sont présentés et comparés.----------ABSTRACT The primary goal of this thesis is to devise and develop a technique of temperature compensation related to the resonant frequency of a microstrip patch antenna (MPA). Such a temperature-compensated microstrip patch antenna capable of standing against a substantial variation of temperature is exploited as part of an ice-sensor for measuring ice loading thickness. Microstrip antennas designed in this way are used in a wireless temperature sensor network in connection with its critical applications of a helicopter de-icing system. A prototype of wireless temperature sensor network which remotely controls turning-on or turning-off heaters intended for de-icing is developed. Among all other antennas, the microstrip antenna is selected due to its versatility. Thanks to the susceptibility of the microstrip patch antenna to external factors, such as temperature fluctuations, its resonant frequency suffers from a stability issue. In addition to that, its resonance causing a narrow frequency bandwidth does not lead to a straightforwardly preferred solution. To minimize the temperature-induced frequency instability and also to prevent losing signal or interferences from adjacent channels, one needs to develop a very efficient and practical temperature compensation technique. In this work, an efficient and practical technique through a resonant frequency temperature compensation for microstrip patch antennas is devised, which is superior to existing counterparts both in its simplicity and frequency stability. To the best of the author`s knowledge, nothing similar was done before. For the first time, a temperature dependence of microstrip antenna resonant frequency is investigated through a mathematical formulation of frequency drift for rectangular, circular, and triangular patch geometries. The circuit model for analyzing temperature impact on microstrip antenna resonant frequency suitable for computer-aided design (CAD) procedures is adopted. Electromagnetic simulations along with results of the adopted circuit model support the derived theory. Results of temperature impact on the frequency drift of microstrip antennas resonant at 2.4 GHz modelled on different substrates are shown and compared. Analysis, simulation, and experimental results show that antennas built on thicker substrates exhibit a better temperature behaviour of the resonant frequency. Based on a theoretically formulated frequency drift, a temperature compensation condition for the rectangular patch geometry of MPA is derived

DNA/BSA interactions and cytotoxic studies of tetradentate N,N,O,O-Schiff base copper(II) complexes: Scientific paper

Three Schiff base Cu(II) complexes, (N,N’-bis(acetylacetone)­propyl­enediimine)copper(II) complex, [Cu(acac2pn)] (1), (N,N'-bis-(ben­zoyl­acet­one)propylenediimine)copper(II) complex, [Cu(phacac2pn)] (2) and (N,N’-bis-(trifluoroacetylacetone)propylenediimine)­copper(II) complex, [Cu(tfacac2pn)] (3), were used to investigate the interactions with calf thymus DNA (ct-DNA) and bovine serum albumin (BSA) using the electronic absorption and spectro­scopic fluorescence methods. UV–Vis absorption studies showed that studied complexes interact with DNA molecule and exhibit moderate binding affinity. Fluorescence studies of complexes 1–3 also showed a possibility for DNA int­ercalation as well as a relatively high binding ability toward BSA. Among the tested complexes, the highest affinity for DNA and BSA molecules was shown by complex 1. Cytotoxic analyses, performed on human colorectal carcinoma HCT-116 and healthy lung fibroblast MRC-5 cell lines, showed that complex 2 exhibited activity on both cell lines, while complexes 1 and 3 did not show any activity

EuReCa ONE—27 Nations, ONE Europe, ONE Registry A prospective one month analysis of out-of-hospital cardiac arrest outcomes in 27 countries in Europe

AbstractIntroductionThe aim of the EuReCa ONE study was to determine the incidence, process, and outcome for out of hospital cardiac arrest (OHCA) throughout Europe.MethodsThis was an international, prospective, multi-centre one-month study. Patients who suffered an OHCA during October 2014 who were attended and/or treated by an Emergency Medical Service (EMS) were eligible for inclusion in the study. Data were extracted from national, regional or local registries.ResultsData on 10,682 confirmed OHCAs from 248 regions in 27 countries, covering an estimated population of 174 million. In 7146 (66%) cases, CPR was started by a bystander or by the EMS. The incidence of CPR attempts ranged from 19.0 to 104.0 per 100,000 population per year. 1735 had ROSC on arrival at hospital (25.2%), Overall, 662/6414 (10.3%) in all cases with CPR attempted survived for at least 30 days or to hospital discharge.ConclusionThe results of EuReCa ONE highlight that OHCA is still a major public health problem accounting for a substantial number of deaths in Europe.EuReCa ONE very clearly demonstrates marked differences in the processes for data collection and reported outcomes following OHCA all over Europe. Using these data and analyses, different countries, regions, systems, and concepts can benchmark themselves and may learn from each other to further improve survival following one of our major health care events

Prevalence, associated factors and outcomes of pressure injuries in adult intensive care unit patients: the DecubICUs study

Funder: European Society of Intensive Care Medicine; doi: http://dx.doi.org/10.13039/501100013347Funder: Flemish Society for Critical Care NursesAbstract: Purpose: Intensive care unit (ICU) patients are particularly susceptible to developing pressure injuries. Epidemiologic data is however unavailable. We aimed to provide an international picture of the extent of pressure injuries and factors associated with ICU-acquired pressure injuries in adult ICU patients. Methods: International 1-day point-prevalence study; follow-up for outcome assessment until hospital discharge (maximum 12 weeks). Factors associated with ICU-acquired pressure injury and hospital mortality were assessed by generalised linear mixed-effects regression analysis. Results: Data from 13,254 patients in 1117 ICUs (90 countries) revealed 6747 pressure injuries; 3997 (59.2%) were ICU-acquired. Overall prevalence was 26.6% (95% confidence interval [CI] 25.9–27.3). ICU-acquired prevalence was 16.2% (95% CI 15.6–16.8). Sacrum (37%) and heels (19.5%) were most affected. Factors independently associated with ICU-acquired pressure injuries were older age, male sex, being underweight, emergency surgery, higher Simplified Acute Physiology Score II, Braden score 3 days, comorbidities (chronic obstructive pulmonary disease, immunodeficiency), organ support (renal replacement, mechanical ventilation on ICU admission), and being in a low or lower-middle income-economy. Gradually increasing associations with mortality were identified for increasing severity of pressure injury: stage I (odds ratio [OR] 1.5; 95% CI 1.2–1.8), stage II (OR 1.6; 95% CI 1.4–1.9), and stage III or worse (OR 2.8; 95% CI 2.3–3.3). Conclusion: Pressure injuries are common in adult ICU patients. ICU-acquired pressure injuries are associated with mainly intrinsic factors and mortality. Optimal care standards, increased awareness, appropriate resource allocation, and further research into optimal prevention are pivotal to tackle this important patient safety threat

Correction to: Prevalence, associated factors and outcomes of pressure injuries in adult intensive care unit patients: the DecubICUs study

The original version of this article unfortunately contained a mistake

Prevalence, associated factors and outcomes of pressure injuries in adult intensive care unit patients: the DecubICUs study

Funder: European Society of Intensive Care Medicine; doi: http://dx.doi.org/10.13039/501100013347Funder: Flemish Society for Critical Care NursesAbstract: Purpose: Intensive care unit (ICU) patients are particularly susceptible to developing pressure injuries. Epidemiologic data is however unavailable. We aimed to provide an international picture of the extent of pressure injuries and factors associated with ICU-acquired pressure injuries in adult ICU patients. Methods: International 1-day point-prevalence study; follow-up for outcome assessment until hospital discharge (maximum 12 weeks). Factors associated with ICU-acquired pressure injury and hospital mortality were assessed by generalised linear mixed-effects regression analysis. Results: Data from 13,254 patients in 1117 ICUs (90 countries) revealed 6747 pressure injuries; 3997 (59.2%) were ICU-acquired. Overall prevalence was 26.6% (95% confidence interval [CI] 25.9–27.3). ICU-acquired prevalence was 16.2% (95% CI 15.6–16.8). Sacrum (37%) and heels (19.5%) were most affected. Factors independently associated with ICU-acquired pressure injuries were older age, male sex, being underweight, emergency surgery, higher Simplified Acute Physiology Score II, Braden score 3 days, comorbidities (chronic obstructive pulmonary disease, immunodeficiency), organ support (renal replacement, mechanical ventilation on ICU admission), and being in a low or lower-middle income-economy. Gradually increasing associations with mortality were identified for increasing severity of pressure injury: stage I (odds ratio [OR] 1.5; 95% CI 1.2–1.8), stage II (OR 1.6; 95% CI 1.4–1.9), and stage III or worse (OR 2.8; 95% CI 2.3–3.3). Conclusion: Pressure injuries are common in adult ICU patients. ICU-acquired pressure injuries are associated with mainly intrinsic factors and mortality. Optimal care standards, increased awareness, appropriate resource allocation, and further research into optimal prevention are pivotal to tackle this important patient safety threat