181 research outputs found
Cyber-Human Systems, Space Technologies, and Threats
CYBER-HUMAN SYSTEMS, SPACE TECHNOLOGIES, AND THREATS is our eighth textbook in a series covering the world of UASs / CUAS/ UUVs / SPACE. Other textbooks in our series are Space Systems Emerging Technologies and Operations; Drone Delivery of CBNRECy – DEW Weapons: Emerging Threats of Mini-Weapons of Mass Destruction and Disruption (WMDD); Disruptive Technologies with applications in Airline, Marine, Defense Industries; Unmanned Vehicle Systems & Operations On Air, Sea, Land; Counter Unmanned Aircraft Systems Technologies and Operations; Unmanned Aircraft Systems in the Cyber Domain: Protecting USA’s Advanced Air Assets, 2nd edition; and Unmanned Aircraft Systems (UAS) in the Cyber Domain Protecting USA’s Advanced Air Assets, 1st edition. Our previous seven titles have received considerable global recognition in the field. (Nichols & Carter, 2022) (Nichols, et al., 2021) (Nichols R. K., et al., 2020) (Nichols R. , et al., 2020) (Nichols R. , et al., 2019) (Nichols R. K., 2018) (Nichols R. K., et al., 2022)https://newprairiepress.org/ebooks/1052/thumbnail.jp
New methods for continuous non-invasive blood pressure measurement
Hlavním cílem této práce je nalezení nové metodiky pro měření kontinuálního neinvazivního krevního tlaku na základě rychlosti šíření pulzní vlny v krevním řečišti. Práce se opírá o rešerši zabývající se základním modelem pro stanovení kontinuálního neinvazivního krevního tlaku na základě měření zpoždění pulzní vlny a jeho rozšířením. Z informací získaných z rešerše se upravila metodika měření doby zpoždění pulzní vlny / rychlosti šíření pulzní vlny, aby bylo možné docílit přesnějších výsledků a omezit tak lidský faktor, který způsobuje významnou nepřesnost vlivem nedokonalého rozmístění senzorů. Rešerše se rovněž podrobně zabývá modely pro stanovení kontinuálního neinvazivního krevního tlaku a jejich úprav zajištujících zvýšení přesnosti. Mezi úpravy modelů zejména patří vstupní parametry popisující krevní oběh - systémový cévní odpor, elasticita cév, tuhost cév. Práce se taky zabývá úpravami stávajícího modelu krevního řečiště pro bližší přizpůsobení fyzického modelu k reálnému cévnímu systému lidského těla. Mezi tyto úpravy patří i funkce baroreflexu či simulace různé tvrdosti stěny umělých cévních segmentů. Protože se jedná o simulační model krevního řečiště, důležitým krokem je také měření tlakové a objemové pulzní vlny, kde není možné využít konvenční senzory pro fotopletysmografii kvůli absenci částic pohlcující světlo. Na základě experimentálního měření pro různé nastavení modelu krevního řečiště bylo provedeno měření pulzní vlny pomocí tlakových a kapacitních senzorů s následným zpracováním měřených signálů a detekcí příznaků charakterizující pulzní vlnu. Na základě příznaku byly stanoveny predikční regresní modely, které vykazovaly dostatečnou přesnost jejich určení, a tak následovaly dvě metody pro získání parametru o tvrdosti cévní stěny na základě měřitelných parametrů. První metodou byl predikční regresní model, který vykazoval přesnost 74,1 % a druhou metodou byl adaptivní neuro-fuzzy inferenční systém, který vykazoval přesnost 98,7 %. Tyto stanovení rychlosti pulzní vlny bylo ověřeno dalším přímým měřením pulzní vlny a výsledky byly srovnány. Výsledkem disertační práce je určení rychlosti šíření pulzní vlny s využitím pouze jednoho pletysmografického senzoru bez nutnosti měření na dvou různých místech s přesným měřením vzdálenosti a možnosti aplikace v klinické praxi.The main objective of this work is to find a new methodology for measuring continuous non-invasive blood pressure based on the pulse wave velocity in the vascular system. The work is based on the literature research of the basic model for the determination of non-invasive continuous blood pressure based on the measurement of pulse transit time. From the information obtained from the review, the methodology of measuring the pulse transit time/pulse wave velocity was modified in order to achieve more accurate results and to reduce the human factor that causes significant inaccuracy due to imperfect sensor placement. The review discusses in detail the models for continuous non-invasive blood pressure estimation and their modifications to ensure increased accuracy. In particular, model modifications include input parameters describing blood circulation - systemic vascular resistance, vascular elasticity, and vascular stiffness. The thesis deals with modifications to the existing physical vascular model to more closely mimic the real vascular system of the human body. These modifications include the baroreflex function or the simulation of different wall hardness of artificial arterial segments. As this is a simulation model of the vascular system, the measurement of pressure and volume pulse wave is also an important step, where it is not possible to use photoplethysmography method due to the absence of light absorbing particles. Based on the experimental measurements for different settings of the vascular model, pulse wave measurements were performed using pressure and capacitive sensors with subsequent processing of the measured signals and detection of the pulse wave features. Predictive regression models were established based on the pulse wave features and showed sufficient accuracy in their determination, followed by two methods for obtaining the parameter on the hardness of the vascular wall based on the measurable parameters. The first method was a predictive regression model, which showed an accuracy of 74.1 %, and the second method was an adaptive neuro-fuzzy inference system, which showed an accuracy of 98.7 %. These pulse wave velocity determinations were verified by further direct pulse wave measurements and the results were compared. The dissertation results in the determination of pulse wave propagation velocity using only one plethysmographic sensor without the need for measurements at two different locations with accurate distance measurements and the possibility of application in clinical practice.450 - Katedra kybernetiky a biomedicínského inženýrstvívyhově
Maternal Hemodynamic Effects of Medical Gases and Uterotonics in Obstetrics
Aim of study: To elucidate the hemodynamic effects of pharmaceutical and medical interventions during pregnancy and childbirth on the mother.Introduction: Oxytocin, oxygen, and nitrous oxide are pharmaceuticals very commonly used in labor and delivery. These pharmaceuticals have known cardiovascular adverse effects. Some of these effects might be detrimental for the mother in case of major blood loss or preexisting cardiovascular disease, but the full extent of these effects is not known. The newer uterotonic carbetocin may have another adverse effect profile.Study population: Pregnant women during elective cesarean section; first trimester pregnant women during scheduled surgery for suction curettage; and pregnant and nonpregnant women during the third trimester.Methods: Cardiovascular effects are measured through ECG, blood pressure, oxygen saturation, and photoplethysmographic pulse wave analysis. By measuring the light absorption of infrared light through the finger, a waveform is obtained, from which it is possible to calculate indices of vascular stiffness and cardiac performance.Results: Oxytocin and carbetocin both have similar effects of vasodilation and blood pressure decrease. Pregnant women experienced more profound subjective side effects from nitrous oxide inhalations than nonpregnant controls. Oxygen alone and in a mix with nitrous oxide have vasoconstrictive and possible negative inotropic effects. These effects were more profound in pregnant women than in nonpregnant controls.Conclusion: The abovementioned medical interventions have cardiovascular effects that are sometimes quite profound. These effects can be shown with a simple and pain-free methodology. Carbetocin seems to have similar cardiovascular adverse effects compared to Oxytocin. Prudence should be taken when administering these drugs to compromised mothers. Both nitrous oxide and oxygen have vasoconstrictive and possible negative inotropic effects that were more prominent in pregnant women than in nonpregnant controls. Some of the effects seen from nitrous oxide might be due to the oxygen fraction in the gas mixture. Awareness of cardiovascular effects is important when treatment of the mother with oxytocin receptor agonists as well as with nitrous oxide and oxygen is considered. Oxygen treatment should not be used without a precise indication
Signal Processing Contributions to Contactless Monitoring of Vital Signs Using Radars
Vital signs are a group of biological indicators that show the status of the body’s life-sustaining functions. They provide an objective measurement of the essential physiological functions of a living organism, and their assessment is the critical first step for any clinical evaluation. Monitoring vital sign information provides valuable insight into the patient's condition, including how they are responding to medical treatment and, more importantly, whether the patient is deteriorating. However, conventional contact-based devices are inappropriate for long-term continuous monitoring. Besides mobility restrictions and stress, they can cause discomfort, and epidermal damage, and even lead to pressure necrosis. On the other hand, the contactless monitoring of vital signs using radar devices has several advantages. Radar signals can penetrate through different materials and are not affected by skin pigmentation or external light conditions. Additionally, these devices preserve privacy, can be low-cost, and transmit no more power than a mobile phone. Despite recent advances, accurate contactless vital sign monitoring is still challenging in practical scenarios. The challenge stems from the fact that when we breathe, or when the heart beats, the tiny induced motion of the chest wall surface can be smaller than one millimeter. This means that the vital sign information can be easily lost in the background noise, or even masked by additional body movements from the monitored subject. This thesis aims to propose innovative signal processing solutions to enable the contactless monitoring of vital signs in practical scenarios. Its main contributions are threefold: a new algorithm for recovering the chest wall movements from radar signals; a novel random body movement and interference mitigation technique; and a simple, yet robust and accurate, adaptive estimation framework. These contributions were tested under different operational conditions and scenarios, spanning ideal simulation settings, real data collected while imitating common working conditions in an office environment, and a complete validation with premature babies in a critical care environment. The proposed algorithms were able to precisely recover the chest wall motion, effectively reducing the interfering effects of random body movements, and allowing clear identification of different breathing patterns. This capability is the first step toward frequency estimation and early non-invasive diagnosis of cardiorespiratory problems. In addition, most of the time, the adaptive estimation framework provided breathing and heart rate estimates within the predefined error intervals, being capable of tracking the reference values in different scenarios. Our findings shed light on the strengths and limitations of this technology and lay the foundation for future studies toward a complete contactless solution for vital signs monitoring
Pacing with restoration of respiratory sinus arrhythmia improved cardiac contractility and the left ventricular output: a translational study
Introduction: Respiratory sinus arrhythmia (RSA) is a prognostic value for patients with heart failure and is defined as a beat-to-beat variation of the timing between the heart beats. Patients with heart failure or patients with permanent cardiac pacing might benefit from restoration of RSA. The aim of this translational, proof-of-principle study was to evaluate the effect of pacing with or without restored RSAon parameters of LV cardiac contractility and the cardiac output
Exercise and nutritional rehabilitation in patients with incurable cancer
BACKGROUND:
Cancer treatments are evolving, so that in many cases cancer is becoming a chronic disease. Rehabilitation is a cornerstone in the management of many chronic diseases, however, it is not yet a routine component of cancer care, in spite of this being advocated (Tiberini R, 2015, Alfano et al., 2016). There is limited evidence for the core components of a rehabilitation programme for patients with incurable cancer. The progressive decline in function and nutritional status in these patients would support an approach that targets these factors. The multi-modal therapeutic approach proposed to treat cancer cachexia, which incorporates exercise and nutrition (Fearon, 2008, Solheim, 2018), has the potential to be adapted as a rehabilitation programme for patients with any type of incurable cancer. However, the feasibility of such a programme remains to be tested.
AIMS:
The aims of this thesis were: firstly, to examine the evidence for combined exercise and nutritional interventions in patients with incurable cancer. A phase II, randomised controlled feasibility trial of an exercise and nutritional rehabilitation programme (ENeRgy) versus standard care was designed and undertaken for patients with incurable cancer. Assessing the primary (feasibility) and secondary (exploratory) endpoints of this trial constitute the second and third aims of this thesis.
METHODS:
A systematic review was undertaken to assess existing evidence for combined exercise and nutritional interventions for patients with incurable cancer. The internationally recognised Grading of Recommendations, Assessment, Development and Evaluation (GRADE) criteria were applied to rank evidence relating to patient-important outcomes, detailed in chapter two.
The ENeRgy trial was undertaken as detailed in chapter three. Eligible participants came from two Edinburgh Hospice community palliative care teams or the Edinburgh tertiary Oncology centre. Participants were ≥18 years of age; Karnofsky Performance Status (KPS) ≥ 60; had a diagnosis of incurable cancer (defined as metastatic or locally advanced cancer not amenable to curative treatment); and were not undergoing anti-cancer therapy. Participants were randomised in a 1:1 ratio to receive an eight-week exercise and nutritional rehabilitation programme (intervention arm) or standard care (control arm). The primary endpoints examined feasibility of the trial and compliance with interventions, while secondary endpoints examined recruitment, retention, participant and carer quality of life (QoL) including sleep parameters. Physical activity measures included mean daily step count measured by physical activity monitor (PAM), two minute walk test (TMWT), timed up and go test (TUG), Life Space Assessment (LSA) and KPS. Nutritional status was measured using weight, the abridged Patient Generated Subjective Global Assessment (aPG-SGA) questionnaire and a ten point verbal scale assessment of nutritional intake (AveS). Overall survival was also measured. All endpoints were assessed at trial baseline (week 0), midpoint (week 5) and endpoint (week 9).
RESULTS:
Systematic Review: There are a limited number of published clinical trials examining combined exercise and nutritional rehabilitation in patients with incurable cancer. However, the existing evidence suggests there are multiple beneficial effects: the highest quality body of evidence pertained to improvements in physical function and depression: graded as moderate (B). Improvements in QoL and fatigue were graded as low (C), and the least quality of evidence (very low, D) related to improvements in overall function and nutrition/ weight.
ENeRgy Trial: Forty-five people (28 males) were recruited over 15 months with an attrition rate of 36% (n=16) with a higher rate of attrition in the control arm (41% vs. 30%). Attrition was mainly due to deterioration in health and no participants withdrew due to the intervention being overly burdensome. Twenty-one participants had a GI or thoracic malignancy and the median [inter-quartile range, IQR] age was 78 years [69-84]. Trial procedures were well tolerated and at least 76% of participants in the treatment arm complied with >80% of the trial interventions. There were no significant differences in participant QoL, with the exception of emotional functioning which remained significantly higher in the intervention arm [P=0.006]. A non-significant improvement in carer QoL was seen in the intervention arm compared to the control arm. There was a non-significant increase in weight in the intervention arm compared to a loss in the control arm (P=0.184). There were no significant differences in step count (P=0.55), TUG (P=0.78), TMWT (P=0.48) and LSA (P=1.0), a-PG-SGA scores (P=0.249), AveS (P=0.398), KPS scores or survival between trial arms.
CONCLUSIONS:
Results of the systematic review suggest that there are multiple benefits to be gained for patients with incurable cancer from combined exercise and nutritional rehabilitation programmes, most notably in terms of physical function and mood. This ostensibly could result in improvements in QoL, but adequately powered trials are lacking.
Results from the ENeRgy trial demonstrate that delivering an exercise and nutritional rehabilitation programme in a hospice outpatient setting is feasible in terms of patient recruitment and compliance with interventions, despite attrition. Furthermore there are potential benefits, including improvements in emotional functioning, carer quality of life and weight, which require a larger phase three trial to fully elucidate. Funding for the follow- on phase three trial ‘ENeRgise’ is currently being sought and the results of this trial could lead to fundamental changes in the way we approach rehabilitation in Palliative Medicine
Biosensors for Diagnosis and Monitoring
Biosensor technologies have received a great amount of interest in recent decades, and this has especially been the case in recent years due to the health alert caused by the COVID-19 pandemic. The sensor platform market has grown in recent decades, and the COVID-19 outbreak has led to an increase in the demand for home diagnostics and point-of-care systems. With the evolution of biosensor technology towards portable platforms with a lower cost on-site analysis and a rapid selective and sensitive response, a larger market has opened up for this technology. The evolution of biosensor systems has the opportunity to change classic analysis towards real-time and in situ detection systems, with platforms such as point-of-care and wearables as well as implantable sensors to decentralize chemical and biological analysis, thus reducing industrial and medical costs. This book is dedicated to all the research related to biosensor technologies. Reviews, perspective articles, and research articles in different biosensing areas such as wearable sensors, point-of-care platforms, and pathogen detection for biomedical applications as well as environmental monitoring will introduce the reader to these relevant topics. This book is aimed at scientists and professionals working in the field of biosensors and also provides essential knowledge for students who want to enter the field
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