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Ecsy, Katharina. "Analgesic effects of EEG alpha-wave entrainment on acute and chronic pain." Thesis, University of Manchester, 2014. https://www.research.manchester.ac.uk/portal/en/theses/analgesic-effects-of-eeg-alphawave-entrainment-on-acute-and-chronic-pain(5559b815-9b2b-48e5-9600-4456d9685c97).html.
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Pharmacological treatments for pain show limited analgesic benefits when compared with placebo. Neuro-modulatory approaches, such as mindfulness meditation and neurofeedback training show more promising effects, but are time consuming and difficult to complete. Neural entrainment provides an almost instantaneous increase in EEG power of the stimulated frequency, achieved with minimal effort through visual flicker stimuli or auditory binaural beats. EEG recorded alpha power displays a reproducible inverse relationship with pain perception. Hence, the main objective of this PhD thesis was to develop an analgesic alpha entrainment intervention: increasing alpha power with the aim to reduce the perception of acute pain in healthy volunteers and chronic pain patients. Prior to attempting to modulate pain, pilot work assessing the ability to entrain alpha power is reported in Chapter 3. A checkerboard stimulus was used to visually entrain frequencies across the alpha band from 7Hz – 14Hz, resulting in a significant power increase at 10Hz and 11Hz. With the goal to reduce behavioural and electrophysiological responses to a moderately painful stimulus, EEG alpha entrainment at 8Hz, 10Hz and 12Hz through auditory binaural beats (in Chapters 4 and 5), and visual flashing LED goggles (in Chapters 4, 6 and 7) was then attempted. A significant reduction of pain ratings was found following both the visual and the auditory alpha stimulation across all three frequencies in Chapters 4,5 and 6. Chapter 5 revealed a significant alpha power increase following 10Hz and 12Hz auditory stimulation. The laser-evoked potential’s (LEP) N2 peak reduced significantly following 10Hz auditory entrainment and the P2 peak reduced significantly across all auditory entrainment conditions. In Chapter 6, alpha power entrained significantly at 8Hz and 10Hz. The P2 peak reduced significantly following the 10Hz visual stimulation. Source analysis showed the precuneus and posterior cingulate cortex might mediate alpha entrainment-induced reductions in LEPs and pain ratings. The paradigm used in Chapter 6 was repeated in osteoarthritic patients in Chapter 7. Significant reductions in pain ratings were observed following all three alpha stimulation sessions, despite a lack of alpha power increase. A significantly reduced response in the P2 peak was also observed following the 12Hz visual stimulation. Decreases in P2 source activity in the posterior insula suggest a functional role in the reduction of pain intensity triggered by alpha stimulation. A significant reduction in the electrophysiological response and the perception of moderately painful stimuli can be achieved through visual or auditory entrainment across the alpha band range, in both healthy volunteers and osteoarthritic patients. The findings from this PhD thesis provide a solid foundation for further investigation of alpha based neuro-modulation as an analgesic intervention.
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Blatný, Michal. "Spektrální analýza EEG signálu." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2011. http://www.nusl.cz/ntk/nusl-219237.
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Master’s thesis deal about electroencefalography, measurement EEG signals and analysis measuermed signals. Project contains two basis practical parts. Firts part contain two PC’s programs that’s are used to fundamental analysis to frequence-domain and visual display of brain mapping created with Matlab. Second chapter of practical parts includes two PC’s programs created with LabView. First of them is the EEG biofeedback making use for advanced analyses and second program is used to detection segment of stacionarity.
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Christ, Gregory J. "EEG slow wave sleep and slow wave activity in extended sleep with bright light induced phase shifts of core body temperature." Thesis, University of Ottawa (Canada), 1994. http://hdl.handle.net/10393/6571.
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In this study, the time courses of slow wave sleep (SWS) and EEG slow wave activity (SWA) were examined in relation to core body temperature (CBT) during extended sleep periods of 15 hours. This investigation examined the merits of a hypothetical 12-hour rhythm of SWS to: (1) confirm its existence; (2) see if it was reflected by the more objective measure of SWA (power spectral analysis); and (3) determine if there was any relationship between this 12-hour rhythm and the CBT rhythm. In Study 1, 7 subjects (age 18-22 years) slept in the laboratory for 3 consecutive nights (2 of 8 hours, then 1 of 15 hours). Rectal CBT was monitored during sleep periods. The main findings were that SWS and SWA both significantly increase in the final 3-hour block over the center 3-hour block, and that these late increases were not related to waking after sleep onset (WASO) or rapid eye movement (REM) sleep. Five of the 7 subjects showed a return of SWA, which was defined by the maximum 15 minute running average in the last 5 hours exceeding the same measure for the previous 4 hours (about 2 sleep cycles with lower SWA). With CBT phase defined as the delay from sleep onset to CBT minimum, it was found that late SWS (in the last 3 hours), and magnitude of the SWA return had significant positive relationships to CBT phase. In Study 2, 3 subjects (age 19, 21, and 29) were studied for 4 series of 4 consecutive nights, with bedtime at 23:30h on all nights. Two series served as baseline (8HBL, and 6HBL). During one series (ML) CBT rhythm was phase advanced using morning bright light (7000-11000 lux, 6:00h-9:00h), and during another series (EL) CBT was delayed using evening bright light (20:00h-23:00h). Subjects were kept in dim light (250 lux) during these morning and evening periods for the 8HBL and 6HBL. A range of CBT phase to sleep timing combinations resulted, with ML always phase advanced relative to EL. CBT phase plotted against late SWS and SWA measures showed a positive association between CBT phase and timing of SWA return (except in one subject (#3)), and a smaller positive association to SWA in the last 3 hours (except in one subject (#1)). When data from Study 1 and the equivalent 8HBL of Study 2 were combined, SWS and SWA late in the sleep period were not significantly related to WASO or REM, and magnitude of the SWA return was statistically significant. There was also a significant relationship between CBT phase and late SWS, magnitude of SWA return, and timing of the SWA return, but not with SWA in the last 3 hours. The data were consistent with a 12-hour rhythm of SWS and SWA, in which the minor pole does not depend solely on WASO or REM, and is related in timing and magnitude to the CBT rhythm. Magnitude of both poles are likely influenced by prior amounts of waking, but the special conditions of extended sleep illustrate the association of the minor pole to the CBT rhythm.
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Taylor, Peter. "Development of compartment models of epileptic spike-wave discharges." Thesis, University of Manchester, 2013. https://www.research.manchester.ac.uk/portal/en/theses/development-of-compartment-models-of-epileptic-spikewave-discharges(4f6f4ff6-f5cd-451f-a806-39590b58468e).html.
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Background: Despite the so-called "generalised" nature of many epileptic seizures, patient specific spatio-temporal properties have been shown using imaging data at the macroscopic level of the cortex. Previous computational models have failed to account for spatial heterogeneities at the scale of the entire cortex. Furthermore, one of they key benefits of developing a model is the ability to easily test stimulation protocols. Previous studies of generalised spike-wave (the hallmark of absence epilepsy) have abstracted away from this.METHODSIn this work we develop a set of models of epileptic activity, one of which is at the scale of the entire cortex and incorporates anatomically relevant connectivity from human subjects. A similar model incorporating physiologically relevant thalamocortical circuitry is developed in order to test hypotheses regarding stimulation protocols.RESULTSWe show that the model can account for large-scale spatio-temporal dynamics similar to those seen in epileptic patients. We demonstrate, using the model of thalamocortical interaction, that such a modelling approach can be used for the evaluation of stimulation protocols which are shown to successfully abort the seizure prematurely.CONCLUSIONThis work highlights the importance of computational modelling to support existing data and to make specific predictions regarding testable hypotheses. For example, a stimulus given at the correct time with the correct amplitude will stop the seizure.
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Zhu, Jian. "THE EFFECTIVENESS OF BUPROPION SR ON DEPRESSIVE SYMPTOMS IN SMOKERS: SELF-REPORTS, EEG, AND INDIVIDUAL DIFFERENCES." OpenSIUC, 2015. https://opensiuc.lib.siu.edu/dissertations/1096.
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Depressive disorders impose a significant mental health burden on individuals and our society. Among smokers there is a high comorbidity of depression/depressive symptoms (e.g., Glassman et al., 1998). Here the parietal EEG alpha asymmetry was used as a dimensional neuropsychological marker of depressive symptoms (i.e., the more depressed, the higher alpha power in the right vs. left parietal lobe during visuospatial tasks [Henriques & Davidson, 1997; Rabe et al, 2005]). Participants, all of whom were smokers and none of whom were clinically depressed, were randomly assigned to the Bupropion group (n = 30) or Placebo group (n = 80) in this double blind study. EEG data during the performance of a visuospatial task were collected prior to and after 14 days on bupropion or placebo capsules. It was found that bupropion significantly reduced the right parietal alpha power and parietal asymmetry whereas placebo did not. Self-reports on depressive symptoms with the Beck Depression Inventory (BDI) were also collected but they did not change after bupropion treatment, suggesting that EEG measures are more sensitive to subtle/early bupropion’s antidepressant effects. Finally the close investigation of individual differences showed that positive (vs. negative) parietal asymmetry during pretreatment predicted greater benefits from bupropion treatment. The present study sheds light on the antidepressant mechanisms of bupropion and represents a valuable addition to the paucity of research on the effects of bupropion on brain activity with EEG measures in general.
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Cajochen, Christian Lorenz Anton. "Heart rate, submental EMG and core body temperature in relation to EEG slow-wave activity during human sleep : effect of light exposure and sleep deprivation /." [S.l.] : [s.n.], 1993. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=10384.
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Webb, Clare E. "Age-related changes in prefrontal cortex function : links between sleep EEG and cognition." Thesis, Loughborough University, 2011. https://dspace.lboro.ac.uk/2134/8545.
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Healthy ageing has been found to be accompanied by changes in slow wave activity (SWA) and cognitive function. Furthermore, these changes have been seen predominantly in the prefrontal cortex (PFC) compared to other regions of the cortex. Current theories of cognitive ageing propose that this occurs due to a specified deterioration of neuronal substrates of the PFC, and as such, changes in SWA and cognitive function may decline at similar rates due to similar underlying aetiology. The main aim of the current thesis was to explore age-related differences in electroencephalographic (EEG) SWA during the first NREM period and cognitive performance that relies on the integrity of the PFC: executive function and social cognition. The extent to which executive function (reliant on dorsolateral PFC areas) and social cognitive function (reliant on ventromedial PFC regions) show similar age-related deterioration was investigated in Study 1. Here, 16 young (22.2 years) and 16 older (71.5 years) adults were administered with a cognitive testing battery including executive function measures: Verbal Fluency (VF) and Tower of London (TOL); as well as measures of social cognition: Go/No-go, Emotional Prosody and Ekman 60 Faces. Not all measures of PFC function were affected to the same extent. The older group performed significantly worse on the TOL, but not on the VF test. Additionally, simple aspects of social cognition did not display differences between the groups, but the older group performed significantly worse than the young group on more complex aspects of recognition of emotion from facial expression (Ekman 60 Faces) and Emotional Prosody. As most studies of cognitive ageing are cross-sectional and show large agerelated changes, the remainder of this thesis focused on age-related changes using a longitudinal design over a relatively small ageing period (mean = 6.29 years). The average age of participants at baseline was 67.1 years and the average age at follow-up was 73.4 years. In Study 2, in a sample of 11 participants, performance on executive function tests was measured (TOL, VF and Wisconsin Card Sorting Test: WCST). As found in the cross-sectional analyses reported in Study 1, the TOL task was found to be the most sensitive indicator of age-related changes, as this showed a decline with age; whereas, VF and WCST remained stable over time. Furthermore, in Study 3, localised SWA was recorded via EEG, and significant declines were found in low frequency delta (0.5 – 1 Hz), which was localised to the left frontal region.
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Kartsch, Morinigo Victor Javier. "Online Alpha Wave detector: an Embedded hardware-software implementation." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2016. http://amslaurea.unibo.it/11819/.
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The recent trend on embedded system development opens a new prospect for applications that in the past were not possible. The eye tracking for sleep and fatigue detection has become an important and useful application in industrial and automotive scenarios since fatigue is one of the most prevalent causes of earth-moving equipment accidents. Typical applications such as cameras, accelerometers and dermal analyzers are present on the market but have some inconvenient. This thesis project has used EEG signal, particularly, alpha waves, to overcome them by using an embedded software-hardware implementation to detect these signals in real time
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Aumann, Dominic [Verfasser]. "Comparative effects of anodal and cathodal slow oscillating transcranial direct current stimulation during slow wave sleep on EEG activity / Dominic Aumann." Lübeck : Zentrale Hochschulbibliothek Lübeck, 2016. http://d-nb.info/1084030128/34.
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Kitic, Srdan. "Cosparse regularization of physics-driven inverse problems." Thesis, Rennes 1, 2015. http://www.theses.fr/2015REN1S152/document.
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Les problèmes inverses liés à des processus physiques sont d'une grande importance dans la plupart des domaines liés au traitement du signal, tels que la tomographie, l'acoustique, les communications sans fil, le radar, l'imagerie médicale, pour n'en nommer que quelques uns. Dans le même temps, beaucoup de ces problèmes soulèvent des défis en raison de leur nature mal posée. Par ailleurs, les signaux émanant de phénomènes physiques sont souvent gouvernées par des lois s'exprimant sous la forme d'équations aux dérivées partielles (EDP) linéaires, ou, de manière équivalente, par des équations intégrales et leurs fonctions de Green associées. De plus, ces phénomènes sont habituellement induits par des singularités, apparaissant comme des sources ou des puits d'un champ vectoriel. Dans cette thèse, nous étudions en premier lieu le couplage entre de telles lois physiques et une hypothèse initiale de parcimonie des origines du phénomène physique. Ceci donne naissance à un concept de dualité des régularisations, formulées soit comme un problème d'analyse coparcimonieuse (menant à la représentation en EDP), soit comme une parcimonie à la synthèse équivalente à la précédente (lorsqu'on fait plutôt usage des fonctions de Green). Nous dédions une part significative de notre travail à la comparaison entre les approches de synthèse et d'analyse. Nous défendons l'idée qu'en dépit de leur équivalence formelle, leurs propriétés computationnelles sont très différentes. En effet, en raison de la parcimonie héritée par la version discrétisée de l'EDP (incarnée par l'opérateur d'analyse), l'approche coparcimonieuse passe bien plus favorablement à l'échelle que le problème équivalent régularisé par parcimonie à la synthèse. Nos constatations sont illustrées dans le cadre de deux applications : la localisation de sources acoustiques, et la localisation de sources de crises épileptiques à partir de signaux électro-encéphalographiques. Dans les deux cas, nous vérifions que l'approche coparcimonieuse démontre de meilleures capacités de passage à l'échelle, au point qu'elle permet même une interpolation complète du champ de pression dans le temps et en trois dimensions. De plus, dans le cas des sources acoustiques, l'optimisation fondée sur le modèle d'analyse \emph{bénéficie} d'une augmentation du nombre de données observées, ce qui débouche sur une accélération du temps de traitement, plus rapide que l'approche de synthèse dans des proportions de plusieurs ordres de grandeur. Nos simulations numériques montrent que les méthodes développées pour les deux applications sont compétitives face à des algorithmes de localisation constituant l'état de l'art. Pour finir, nous présentons deux méthodes fondées sur la parcimonie à l'analyse pour l'estimation aveugle de la célérité du son et de l'impédance acoustique, simultanément à l'interpolation du champ sonore. Ceci constitue une étape importante en direction de la mise en œuvre de nos méthodes en en situation réelleInverse problems related to physical processes are of great importance in practically every field related to signal processing, such as tomography, acoustics, wireless communications, medical and radar imaging, to name only a few. At the same time, many of these problems are quite challenging due to their ill-posed nature. On the other hand, signals originating from physical phenomena are often governed by laws expressible through linear Partial Differential Equations (PDE), or equivalently, integral equations and the associated Green’s functions. In addition, these phenomena are usually induced by sparse singularities, appearing as sources or sinks of a vector field. In this thesis we primarily investigate the coupling of such physical laws with a prior assumption on the sparse origin of a physical process. This gives rise to a “dual” regularization concept, formulated either as sparse analysis (cosparse), yielded by a PDE representation, or equivalent sparse synthesis regularization, if the Green’s functions are used instead. We devote a significant part of the thesis to the comparison of these two approaches. We argue that, despite nominal equivalence, their computational properties are very different. Indeed, due to the inherited sparsity of the discretized PDE (embodied in the analysis operator), the analysis approach scales much more favorably than the equivalent problem regularized by the synthesis approach. Our findings are demonstrated on two applications: acoustic source localization and epileptic source localization in electroencephalography. In both cases, we verify that cosparse approach exhibits superior scalability, even allowing for full (time domain) wavefield interpolation in three spatial dimensions. Moreover, in the acoustic setting, the analysis-based optimization benefits from the increased amount of observation data, resulting in a speedup in processing time that is orders of magnitude faster than the synthesis approach. Numerical simulations show that the developed methods in both applications are competitive to state-of-the-art localization algorithms in their corresponding areas. Finally, we present two sparse analysis methods for blind estimation of the speed of sound and acoustic impedance, simultaneously with wavefield interpolation. This is an important step toward practical implementation, where most physical parameters are unknown beforehand. The versatility of the approach is demonstrated on the “hearing behind walls” scenario, in which the traditional localization methods necessarily fail. Additionally, by means of a novel algorithmic framework, we challenge the audio declipping problemregularized by sparsity or cosparsity. Our method is highly competitive against stateof-the-art, and, in the cosparse setting, allows for an efficient (even real-time) implementation
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Kašpar, Blahoslav. "Monitor alfa aktivity." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2012. http://www.nusl.cz/ntk/nusl-219517.
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This work deals with problems of EEG biofeedback and possibilities of its use in therapy. The method of EEG biofeedback helps patients to achieve the state of relaxation. It is a noninvasive treatment modality. The paper also discussed the requirements for each component unit. The main point of a design and construction of Alpha activity monitor, a device implementing EEG biofeedback focused on sensing electrical activity of the brain, specifically alpha waves. Alpha activity is specific and their parameters are taken into account when selecting components and construction equipment. Custom feedback is then for the appearance of alpha activity mediated by the headphones in acoustic form. The work also includes design of electrical circuits and electrical diagram of the overall apparatus including a list of used parts. Electrical diagrams are formed in the EAGLE 6.1.0.
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Ascolani, Gianluca. "EEG, Alpha Waves and Coherence." Thesis, University of North Texas, 2010. https://digital.library.unt.edu/ark:/67531/metadc28389/.
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This thesis addresses some theoretical issues generated by the results of recent analysis of EEG time series proving the brain dynamics are driven by abrupt changes making them depart from the ordinary Poisson condition. These changes are renewal, unpredictable and non-ergodic. We refer to them as crucial events. How is it possible that this form of randomness be compatible with the generation of waves, for instance alpha waves, whose observation seems to suggest the opposite view the brain is characterized by surprisingly extended coherence? To shed light into this apparently irretrievable contradiction we propose a model based on a generalized form of Langevin equation under the influence of a periodic stimulus. We assume that there exist two different forms of time, a subjective form compatible with Poisson statistical physical and an objective form that is accessible to experimental observation. The transition from the former to the latter form is determined by the brain dynamics interpreted as emerging from the cooperative interaction among many units that, in the absence of cooperation would generate Poisson fluctuations. We call natural time the brain internal time and we make the assumption that in the natural time representation the time evolution of the EEG variable y(t) is determined by a Langevin equation perturbed by a periodic process that in this time representation is hardly distinguishable from an erratic process. We show that the representation of this random process in the experimental time scale is characterized by a surprisingly extended coherence. We show that this model generates a sequence of damped oscillations with a time behavior that is remarkably similar to that derived from the analysis of real EEG's. The main result of this research work is that the existence of crucial events is not incompatible with the alpha wave coherence. In addition to this important result, we find another result that may help our group, or any other research group working on the analysis of brain's dynamics, to prove or to disprove the existence of crucial events. We study the diffusion process generated by fluctuations emerging from the same model after filtering out the alpha coherence, and we study the recursion to the origin. We study the survival probability of this process, namely the probability that up to a given time no re-crossing of the origin occurs. We find that this is an inverse power law with a power that depends on whether or not crucial events exist.
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Toušek, Vojtěch. "Detekce a rozměřování v signálu EKG." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2008. http://www.nusl.cz/ntk/nusl-217208.
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Automatic detection and delineation of ECG characteristic points is a basic procedure of any analyze of ECG using computer. This detection is a necessary step to simplify the work of cardiologists to evaluate long ECG records. In this thesis is proposed and evaluate a method of detection and delineation in a single-lead ECG using dyadic wavelet transform followed by correction in pseudo-orthogonal lead system taken from standard 12-lead system. The method uses information about position of positive maximum – negative minimum pair to detect ECG characteristic waves. At first the QRS complex is detected and than its morphology (waves Q and S) and the onset and end of the complex. After that the T-wave is detected and delineated within a searching window dependent on QRS position. And last the P-wave is detected and delineated. There are used two types of wavelets in developed method, “haar” and “quadratic spline”. The developed method was evaluated on CSE database. When haar wavelet was used the QRS detector sensitivity was 99.14%. In the work is also evaluated the accuracy of delineation characteristic points. As the P-wave and QRS complex delineation produced quite good results the T-wave end delineator produced relatively big deviations. All deviations are presented in histograms.
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Valluri, Sasanka. "DETECTION OF THE R-WAVE IN ECG SIGNALS." Master's thesis, University of Central Florida, 2005. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/2122.
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This thesis aims at providing a new approach for detecting R-waves in the ECG signal and generating the corresponding R-wave impulses with the delay between the original R-waves and the R-wave impulses being lesser than 100 ms. The algorithm was implemented in Matlab and tested with good results against 90 different ECG recordings from the MIT-BIH database. The Discrete Wavelet Transform (DWT) forms the heart of the algorithm providing a multi-resolution analysis of the ECG signal. The wavelet transform decomposes the ECG signal into frequency scales where the ECG characteristic waveforms are indicated by zero crossings. The adaptive threshold algorithms discussed in this thesis search for valid zero crossings which characterize the R-waves and also remove the Preventricular Contractions (PVC's). The adaptive threshold algorithms allow the decision thresholds to adjust for signal quality changes and eliminate the need for manual adjustments when changing from patient to patient. The delay between the R-waves in the original ECG signal and the R-wave impulses obtained from the algorithm was found to be less than 100 ms.M.S.
Department of Electrical and Computer Engineering
Engineering and Computer Science
Electrical Engineering
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Lacko, Michal. "Potlačení síťového rušení v signálech EKG." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2010. http://www.nusl.cz/ntk/nusl-218657.
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This project includes survey of various methods ECG signal filtering, to suppress of powerline interference. It is specialized especially on properties which affecting the quality of filtration. The main essence of project is evaluation of the proposed methods in terms of quality and the least possible distortion of the resulting ECG signal. The work is focused on linear, adaptive filtering and filtering using discrete wavelet trans-form. Signal processing and evaluation of descriptive parameters are transferred using the graphical interface GUI in the program Matlab 7.7.0 ( R2008b ).
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York-Andersen, Anna Henrietta. "Investigating the calcium wave and actin dynamics at Drosophila egg activation." Thesis, University of Cambridge, 2019. https://www.repository.cam.ac.uk/handle/1810/288873.
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Egg activation is a series of highly coordinated processes that prepare the mature oocyte for embryogenesis. Typically associated with fertilisation, egg activation results in the resumption of the cell cycle, expression of maternal mRNAs and cross-linking of the vitelline membrane. While some aspects of egg activation, such as initiation factors in mammals and environmental cues in sea animals, have been well-documented, the mechanics of egg activation in many animals are still not well understood. This is especially true for animals where fertilisation and egg activation are unlinked. In order to elucidate how egg activation is regulated independently of fertilisation, I use Drosophila melanogaster as a model system. This insect provides extensive genetic tools, ease of manipulation for experimentation and is amenable for imaging. Through visualisation of calcium, Processing bodies and meiotic spindles, I show that osmotic pressure acts as an initiation cue for the calcium wave and downstream processes, including the resumption of cell cycle and the dispersion of the translational repression sites. I further show that aquaporin channels, together with external sodium ions, play a role in coordinating swelling of the oocyte in response to the osmotic pressure. I proceed to identify the requirement of internal calcium sources together with a dynamic actin cytoskeleton for a calcium wave to occur. Through co-visualisation of calcium and actin, I provide the first evidence that the calcium wave is followed by a wavefront of non-cortical F-actin at egg activation, which requires the calcium wave. Genetic analysis supports a model where changes in osmotic pressure trigger the calcium wave via stretch sensitive calcium channels in the oocyte membrane and the calcium wave is relayed by nearby channels via the actin cytoskeleton. My work concludes that the mechanism of egg activation in Drosophila is more similar to plants, compared to most vertebrates.
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Gruetzmann, Anna [Verfasser]. "Wireless ECG Sensor in Surface Acoustic Wave Transponder Technology / Anna Gruetzmann." München : Verlag Dr. Hut, 2010. http://d-nb.info/1009484524/34.
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Lin, Chao. "P and T wave analysis in ECG signals using Bayesian methods." Phd thesis, Toulouse, INPT, 2012. http://oatao.univ-toulouse.fr/8990/1/lin.pdf.
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This thesis studies Bayesian estimation/detection algorithms for P and T wave analysis in ECG signals. In this work, different statistical models and associated Bayesian methods are proposed to solve simultaneously the P and T wave delineation task (determination of the positions of the peaks and boundaries of the individual waves) and the waveform-estimation problem. These models take into account appropriate prior distributions for the unknown parameters (wave locations and amplitudes, and waveform coefficients). These prior distributions are combined with the likelihood of the observed data to provide the posterior distribution of the unknown parameters. Due to the complexity of the resulting posterior distributions, Markov chain Monte Carlo algorithms are proposed for (sample-based) detection/estimation. On the other hand, to take full advantage of the sequential nature of the ECG, a dynamic model is proposed under a similar Bayesian framework. Sequential Monte Carlo methods (SMC) are also considered for delineation and waveform estimation. In the last part of the thesis, two Bayesian models introduced in this thesis are adapted to address a specific clinical research problem referred to as T wave alternans (TWA) detection. One of the proposed approaches has served as an efficient analysis tool in the Endocardial T wave Alternans Study (ETWAS) project in collaboration with St. Jude Medical, Inc and Toulouse Rangueil Hospital. This project was devoted to prospectively assess the feasibility of TWA detection in repolarisation on EGM stored in ICD memories.
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Anderson, Clare. "The pre-frontal cortex : links between neuropsychological performance and the sleep and wake EEG." Thesis, Loughborough University, 2003. https://dspace.lboro.ac.uk/2134/33960.
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The Pre-Frontal Cortex (PFC) has one of the highest Cerebral Metabolic Rates (CMR) during wakefulness (Braun et al., 1997, Maquet et al., 1990) and the lowest CMR during Slow Wave Sleep (SWS) at night (Maquet, 2000) .Inasmuch that the PFC is a focus for low frequency delta activity (e g. Werth et al., 1996, 1997), generated directly by the cortex (Steriade et al., 1993a-c), it is argued, here, that this serves a localised function of sleep and is thus reflective of enhanced recovery. Given the PFC-delta activity link, Clark et al. (1998) assessed daytime regional cerebral blood flow (rCBF) and found increased 'brainwork' during the day resulted in increased delta activity at night, specifically in the (left) PFC.
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Cepek, Tomáš. "Planární anténa na EBG substrátu." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2014. http://www.nusl.cz/ntk/nusl-221013.
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The aim of the thesis is to describe EBG substrate and exminate his influence on some types of antennas and choose one of them for realization. In first part this thesis describes the paramaeters of antenna in generall, in the second part is dedicated to introduction with EBG substrate mainly on the surface with the high impedance (HIES). The third part deals with the simulations of microstrip patch antennas with EBG substrate and without EBG substrate. In the last parts was designed and optimized antenna using superstrate.
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Brandejs, Jakub. "Detekce parametrů repolarizace ze signálu EKG." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2014. http://www.nusl.cz/ntk/nusl-220848.
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A T wave peak and offset detector based on an unpublished lead transformation that can be briefly described as multilead linear regression was proposed and implemented afterwards. Potential of the transformation as a useful QRS detection tool was revealed later on. Proposed QRS detector was put to the test of CSE database. Results were compared with work of other authors. Results of T wave peak and offset detector were introduced in visual way.
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Liu, Qing. "Design and fabrication of long-period waveguide gratings /." access full-text access abstract and table of contents, 2005. http://libweb.cityu.edu.hk/cgi-bin/ezdb/thesis.pl?phd-ee-b19887887a.pdf.
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Thesis (Ph.D.)--City University of Hong Kong, 2005."Submitted to Department of Electronic Engineering in partial fulfillment of the requirements for the degree of Doctor of Philosophy" Includes bibliographical references.
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Arbon, Emma Louise. "The EEG as a biomarker for individual differencesin the physiology and pharmacology of sleep-wake regulation." Thesis, University of Surrey, 2013. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.604333.
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There are prominent individual differences in sleep pattel11s and some of these can be observed within the EEG. In order to determine whether the EEG can effectively serve as a biomarker for individual differences and in order to establish whether such differences constituted trait-like individual differences, we assessed the stability and robustness of sleep and the sleep EEG in physiological and pharmacological studies. The spectral composition of the EEG and PSG derived sleep measures were assessed for trait- like inter-individual variability by calculating ICCs in 1) a study investigating the effects of sleep extension, sleep restriction and total sleep deprivation on sleep and the EEG and the contribution of the PER3 polymorphism to individual differences 2) a study investigating the effects of polychromatic light mixtures on the EEG and 3) a study investigating the effects of prolonged-release melatonin, temazepam and zolpidem on sleep and the EEG. Absolute power density values derived from the spectral composition of the EEG werc particularly stable and robust and the ICCs were rated as 'moderate' to 'almost perfect' for NREM and REM sleep across the studies. ICCs for PSG measures were more variable. ICCs were also calculated on relative data in order to assess the stability and robustness of the response to sleep-wake manipulations in the first study; however, these ICCs were very low in comparison to those obtained for absolute data. The PER3 polymorphism differentially affected the some PSG measures and the EEG in our study population. In conclusion, we have provided further evidence for trait-like individual differences within sleep and the EEG, and as such the EEG does effectively serve as a biomarker for individual differences. However, whether these individual differences relate only to phenomena of the EEG or whether they relate to individual differences in sleep-wake regulation needs further investigation.
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Richter, Zdeněk. "Vícesvodová rozhodovací pravidla v rozměřování signálů EKG." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2012. http://www.nusl.cz/ntk/nusl-219529.
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This work deals with ECG signal measuring and methods of its processing. It compares some of the QRS detection methods and describes some of the testing databases. In this work a detector of QRS complex is realized, it is based on the approach of zero crossings. Next section makes combination of results from separate leads to one, which improves efficiency of detection. One section of this work deals with design and realization delination of ECG signal. In the last part outputs of this delineation are compared with the results of the other authors.
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Moulessehoul-Ounnas, Malika. "Conception et mise en oeuvre de l'interface d'acquisition et de transmission d'un réseau de capteurs sans fil : application à la mesure de signaux électrophysiologiques." Thesis, Tours, 2009. http://www.theses.fr/2009TOUR4043.
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Ce travail de thèse consiste en une étude théorique et expérimentale d'un système detransmission à application universelle. Un système de capteurs ou multi-capteurs sans filsdédié à des différentes applications ayant comme point commun, une basse amplitude. Ils'inspire donc des plates forme des réseaux sans fils existant dans le monde technologique.Nous présentons dans ce mémoire les différentes raisons qui expliquent l'intérêt majeursuscité par un tel système, nous aborderons plus profondément une des applications dusystème, à savoir le domaine neurophysiologique. A partir des choix d'architecture et dessimulations expérimentales correspondantes nous relayons étape par étape les différentesphases qui nous ont mené à réaliser les prototypes en tenant en compte les résultats desuns et des autres, pour finir ensuite par une étude comparative des différents prototypesréalisés et des perspectives envisagéesThis thesis work is a theoretical and experimental study of a universal applicationtransmission system. A wireless sensor or multi-sensor system dedicated to different low-magnitudeapplications. It is inspired from wireless networks platforms of the moderntechnological world.In this dissertation, the different reasons for the interest aroused by such a system, arepresented, we will more deeply study one of the applications of this system, namely theneurophysiological area. From the choice of the architecture and corresponding experimentalsimulations we will explain, step by step, the different phases which led us to realize theprototypes taking into account the results of each phase, then finally a comparative studyof different prototypes realized and the prospects envisaged
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Maloney, Karen J. "High frequency gamma EEG activity in association with sleep-wake states and spontaneous behaviors in the rat." Thesis, McGill University, 1996. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=23918.
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The occurrence of high frequency, gamma EEG activity (30-60 Hz) was bands and in investigated by spectral analysis in relationship to other frequency association with the natural sleep-waking cycle and spontaneous behaviors of the rat. High frequency, gamma waves are present and occur intermittently on the filtered and unfiltered EEG across the sleep-waking cycle. Gamma activity is distinctive from other high frequency bands, in that the amplitude varies systematically in association with (1) state, having the highest amplitude in Waking and Paradoxical Sleep (PS) as compared to Slow Wave Sleep (SWS) and, (2) behavior, having the highest amplitude in attentive and active waking behaviors and 'active' sleep with twitches indicative of PS, as compared to quiet waking and 'quiet' sleep. Coherence in gamma activity also varies as a function of state-behavior, having the highest values in Waking moving and PS. Gamma activity varies positively with theta and inversely with delta activity over the sleep-waking cycle. Gamma activity is thus shown to reflect the degree of behavioral and cortical arousal.
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Mariam, Tasnuva. "Burst-suppression events and fast, large-amplitude, sharp waves in the cortical EEG during deep isoflurane coma." Thesis, University of British Columbia, 2015. http://hdl.handle.net/2429/54331.
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Di, Fusco Greta. "A Reliable Downscaling of ECG Signals for the Detection of T wave Heterogeneity Features." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2016.
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In cardiovascular disease the definition and the detection of the ECG parameters related to repolarization dynamics in post MI patients is still a crucial unmet need. In addition, the use of a 3D sensor in the implantable medical devices would be a crucial mean in the assessment or prediction of Heart Failure status, but the inclusion of such feature is limited by hardware and firmware constraints.
The aim of this thesis is the definition of a reliable surrogate of the 500 Hz ECG signal to reach the aforementioned objective. To evaluate the worsening of reliability due to sampling frequency reduction on delineation performance, the signals have been consecutively down sampled by a factor 2, 4, 8 thus obtaining the ECG signals sampled at 250, 125 and 62.5 Hz, respectively. The final goal is the feasibility assessment of the detection of the fiducial points in order to translate those parameters into meaningful clinical parameter for Heart Failure prediction, such as T waves intervals heterogeneity and variability of areas under T waves.
An experimental setting for data collection on healthy volunteers has been set up at the Bakken Research Center in Maastricht. A 16 – channel ambulatory system, provided by TMSI, has recorded the standard 12 – Leads ECG, two 3D accelerometers and a respiration sensor. The collection platform has been set up by the TMSI property software Polybench, the data analysis of such signals has been performed with Matlab.
The main results of this study show that the 125 Hz sampling rate has demonstrated to be a good candidate for a reliable detection of fiducial points. T wave intervals proved to be consistently stable, even at 62.5 Hz. Further studies would be needed to provide a better comparison between sampling at 250 Hz and 125 Hz for areas under the T waves.
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Alaei, Sahar. "A POSSIBLE LINK BETWEEN R-WAVE AMPLITUDE ALTERNANS AND T-WAVE ALTERNANS IN ECGs." UKnowledge, 2019. https://uknowledge.uky.edu/cbme_etds/57.
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Sudden Cardiac Death (SCD) is the largest cause of natural deaths in the USA, accounting for over 300,000 deaths annually. The major reason for SCD is Ventricular Arrhythmia (VA). Therefore, there is need for exploration of approaches to predict increased risk for VA. Alternans of the T wave in the ECG (TWA) is widely investigated as a potential predictor of VA, however, clinical trials show that TWA has high negative predictive value but poor positive predictive value. A possible reason that TWA has a large number of false positives is that a pattern of alternans known as concordant alternans, may not be as arrhythmogenic as another pattern which is discordant alternans. Currently, it is not possible to discern the pattern of alternans using clinical ECGs. Prior studies from our group have showed that alternans of the maximum rate of depolarization of an action potential also can occur when Action Potential Duration (APD) alternans occurs and the relationship between these two has the potential to create spatial discord. These results suggest that exploration of the co-occurrence of depolarization and repolarization alternans has the potential to stratify the outcome of TWA tests. In order to investigate the link between depolarization alternans and changes in ECGs, we used a mathematical model created previously in our research group which simulated ECGs from the cellular level changes observed in our experimental studies. These results suggest that the changes in ECGs should appear as alternating pattern of the amplitude of the R wave. Because there are a variety of factors which may also cause the R wave amplitude to change, we used signal analysis and statistical modeling to determine the link between the observed changes in R wave amplitude and depolarization alternans. Results from ECGs recorded from patients show that amplitude of the R wave can change as predicted by our experimental results and mathematical model. Using TWA as the marker of repolarization alternans and R Wave Amplitude Alternans (RWAA) as the marker of depolarization alternans, we investigated the phase relation between depolarization and repolarization alternans in clinical grade ECG and observed that this relationship does change spontaneously, consistent with our prior results from animal studies. Results of the present study support further investigation of the use of RWAA as a complementary method to TWA to improve its positive predictive value.
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Miles, Alan Douglas. "A continued musical and personal dialogue with the waves of epilepsy." Thesis, University of Plymouth, 2018. http://hdl.handle.net/10026.1/11575.
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In the early hours of the morning several years ago I awoke with paramedics leaning over me. In a state of confusion, my first conscious decision was to enter my music production studio while they attempted to lead me to the ambulance. Music was important to me even in a disorientated post-ictal state (an altered state of consciousness following a seizure). Two weeks later I awoke with paramedics standing over me again. I had started to experience multiple seizures. During the previous weeks, I also experienced numerous incidents of memory loss when delivering presentations at work, feelings of being returned to the room following an absence of consciousness and suffering from temporal disorientation. I also experienced multiple episodes of déjà vu, aromas that were difficult to identify, visual distortions and waves of euphoria like momentary intoxication of an unknown origin. These experiences began to increase in frequency until my first tonic-clinic seizure. Following medical tests, I was diagnosed with epilepsy. It was a confusing period with no history of epilepsy in my family and no physiological causes could be identified. I viewed epilepsy as an overwhelming authority, it takes control of your life and asserts its power upon you, forcibly changing your reality in an instant. When I saw the EEG readouts from my tests I noticed how similar they were to sound waves. As an electronic musician, this project is being used as an artistic and cathartic opportunity to creatively transform the power of epilepsy and reassert my personal identity upon it. Symbolically reclaiming personal control and creatively transforming the psychological perception of personal power that is lost through the experience of epilepsy. Transforming it from an internal destructive force into an external and creative activity in my life. Capturing the cultural and emotional experiences of epilepsy and transforming them into cinematic electronic soundscapes using research and musical experimentation with EEG epilepsy signals. It is an existential exploration, the results will be tangible, accessible and reasonable in the transformation of the EEG epilepsy recordings from the uncontrollable unconscious into the creative conscious. This project will apply transposition, mathematics, research and creative exploration to map epilepsy EEG events into computer synthesized soundscapes, transforming the passive nature of diagnoses and treatment into a proactive and creative process. This thesis shares an individual's research and experiences of epilepsy with a community that have an interest in transforming the passive sufferer into a creatively active and articulate patient. Professor Dan Lloyd (Thomas C. Brownell) Professor of Philosophy at Trinity College states that: “It is observed that fMRI (Brain) activity is more similar to music than it is to language ... ” Lloyd D. (2011). If, as Lloyd suggests, brain activity is more like music than language then what might epilepsy be saying or possibly singing during these events? What are the audible timbres of these events? Researchers such as Wu et al, Psyche et al, Chafe and Parvizi have previously interpreted EEG data of epilepsy EEG events to aid medical research, but it is not exploring the emotional timbre of epilepsy from a patient’s perspective. The previous research derived musical notes from EEG signals to trigger MIDI instruments and modulate non-epilepsy related audio sources for medical identification purposes. This project examines the possible timbres derived directly from the EEG data to explore and creatively describe the emotional and physical experience from a patient’s perspective. This thesis presents the personal experience of epilepsy, the development of electroencephalography (EEG), the sociocultural history of epilepsy. the sonification and musification of EEG data, plus the concepts involved in the design of timbre and sound effect. For this project, a bespoke granular synthesizer called ‘The Oblique-Granizer’ (programmed with Cycling74's MAXMSP) has been constructed that employs EEG signals, converted to digital audio, to synthesize timbres that explore the description of human experience and emotions related to epilepsy. This thesis includes research that has been carried out into mathematical algorithms to generate musical notes and melodic information in electronic music compositions using EEG epilepsy seizure activity. The aim is to take back personal control by creatively transforming the EEG data and my psychological perception of epilepsy into electronic soundscapes and sonic textures through exploration of sonification and musification techniques.
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Souza, Rafael Navarenho de. "Estudo comparativo do comportamento elétrico entre os MOSFETS dos tipos wave e convencionais equivalentes operando em ambientes de radiações ionizantes/." reponame:Biblioteca Digital de Teses e Dissertações da FEI, 2016. https://doi.org/10.31414/EE.2016.T.128554.
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Bajgar, Jiří. "Detekce P vlny v EKG signálech." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2015. http://www.nusl.cz/ntk/nusl-221317.
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The aim of this diploma thesis is to introduce methods of detection of the QRS complex and the subsequent detection of P waves. The intention is to create a program by specified method in the software Matlab which will be able to implement this method. The thesis describes the basic and important methods of detection and subsequent algorithm to detect P waves. Solution of the algorithm is tested on real data. It also describes the automatic signal evaluation and the results of this automatic function.
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Boudová, Markéta. "Segmentace skrytých P vln pomocí metod hlubokého učení." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2021. http://www.nusl.cz/ntk/nusl-442578.
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The aim of this thesis is segmentation of P waves in ECG signals. The theoretical part of the thesis describes the physiology of the heart and the basics of deep learning methods. Preprocessing of the signals is performed and neural network U-Net is implemented in the Python software environment in the practical part. Afterwards, optimization of network architecture is performed in order to reduce model complexity. Lastly the success rate of the model is evaluated.
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Kesek, Milos. "Traces of Repolarization Inhomogeneity in the ECG." Doctoral thesis, Uppsala : Acta Universitatis Upsaliensis : Univ.-bibl. [distributör], 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-5747.
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Mo, Tingting. "Coplanar waveguide components and their applications in microwave circuits /." access abstract and table of contents access full-text, 2006. http://libweb.cityu.edu.hk/cgi-bin/ezdb/thesis.pl?phd-ee-b21471514a.pdf.
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Thesis (Ph.D.)--City University of Hong Kong, 2006."Submitted to Department of Electronic Engineering in partial fulfillment of the requirements for the degree of Doctor of Philosophy" Includes bibliographical references.
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Řezáč, Petr. "Rozměření signálu EKG pro analýzu TWA." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2008. http://www.nusl.cz/ntk/nusl-217734.
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The thesis deals with possibilities of using wavelet transform in the field of surface electrocardiogram (ECG) signals denoising and ECG signals measuring. Several algorithms have been used to detect and estimate T-wave alternans (TWA), such as spectral method (SM), Poincaré Mapping (PM) or correlation method (CM). T-wave alternans, also called repolarization alternans, is a phenomenon appearing in the electrocardiogram as a consistent fluctuation in the repolarization morphology on every-other-beat basis. Electrical TWA has been recognized as a marker of electrical instability, and has been shown to be related with patients at increased risk for ventricular arrhytmias. Presence of TWA has been reported in a wide range of clinical and experimental situations including long QT syndrome, myocardial infarction, angina pectoris, acute ischemia, etc. Projected methods of detection TWA are realized in Matlab software, and they are experimentally verified on real ECG signals from the European ST-T Database.
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Schmidt, Martin, Mathias Baumert, Hagen Malberg, and Sebastian Zaunseder. "T Wave Amplitude Correction of QT Interval Variability for Improved Repolarization Lability Measurement." Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2017. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-217300.
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Objectives: The inverse relationship between QT interval variability (QTV) and T wave amplitude potentially confounds QT variability assessment. We quantified the influence of the T wave amplitude on QTV in a comprehensive dataset and devised a correction formula.
Methods: Three ECG datasets of healthy subjects were analyzed to model the relationship between T wave amplitude and QTV. To derive a generally valid correction formula, linear regression analysis was used. The proposed correction formula was applied to patients enrolled in the Evaluation of Defibrillator in Non-Ischemic Cardiomyopathy Treatment Evaluation trial (DEFINITE) to assess the prognostic significance of QTV for all-cause mortality in patients with non-ischemic dilated cardiomyopathy.
Results: A strong inverse relationship between T wave amplitude and QTV was demonstrated, both in healthy subjects (R2 = 0.68, p < 0.001) and DEFINITE patients (R2 = 0.20, p < 0.001). Applying the T wave amplitude correction to QTV achieved 2.5-times better group discrimination between patients enrolled in the DEFINITE study and healthy subjects. Kaplan-Meier estimator analysis showed that T wave amplitude corrected QTVi is inversely related to survival (p < 0.01) and a significant predictor of all-cause mortality.
Conclusion: We have proposed a simple correction formula for improved QTV assessment. Using this correction, predictive value of QTV for all-cause mortality in patients with non-ischemic cardiomyopathy has been demonstrated.
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Ruijter, Judith Magdalena Paulina de. "Occupational wage differences : a gender approach = Loonverschillen tussen beroepen : een gender benadering /." Rotterdam, 2002. http://aleph.unisg.ch/hsgscan/hm00062039.pdf.
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Peck, Tucker. "Factor Structure among Possible Correlates of Skill at Mindfulness Meditation." Diss., The University of Arizona, 2015. http://hdl.handle.net/10150/577185.
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Despite the growing interest in the general public and popular press about the scientific research into mindfulness meditation (e.g. Pickert, 2014), several critiques of this research have been published in the past few years outlining methodological flaws in many published studies on the topic (Goyal et al., 2014; Ospina et al., 2007). One potential way to improve methodology in this field would be to find better ways of measuring skill at meditation, giving researchers an ability to compare more advanced practitioners to those who are more novice. A total of 69 participants were recruited. Pilot data were collected from 33 participants and analyzed using exploratory methods to assess whether any self-report measures of mindfulness practice might correlate with any physiological variables thought to possibly reflect a dimension of skill at meditation. Participants spent a night in the sleep lab, and prior to their sleep study spent six minutes in a baseline condition followed by six minutes in a meditation condition, and differences were recorded on a number of physiological measures. Correlational analyses revealed that, of the physiological and self-report measures, six were correlated with other measures, and principal component analysis found 2 factors, each with three components. 36 additional participants were then recruited in an attempt to determine whether these two factors would replicate, and this latter group participated only in the meditation protocol. Both factors were largely replicated independently in the second sample and remained stable collapsing the two groups together. Factor 1 combined an increase in both alpha and theta power centrally and occipitally between baseline and meditation with self-reported mindfulness practice, and Factor 2 combined the inverse of the Brief Symptom Inventory, the Mindful Attention and Awareness Scale, and the change in respiration between baseline and meditation.
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Mendes, de Souza Poliana. "Study of short-wave ultraviolet treatments (UV-C) as a non-thermal preservation process for liquid egg products." Doctoral thesis, Universitat Politècnica de València, 2012. http://hdl.handle.net/10251/16696.
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La viabilidad de los tratamientos con radiación ultravioleta (UV-C) a 254 nm como proceso no térmico para la conservación de ovoproductos líquidos fue evaluada desde el punto de vista de la eficiencia en la descontaminación y sus efectos en los atributos de calidad. Los estudios cinéticos sobre la inactivación de microorganismos inoculados y de los principales grupos de microorganismos alterantes sirvieron para discriminar los parámetros más relevantes del tratamiento con UV-C. Los estudios de vida útil sirvieron para evaluar las ventajas aportadas por esta tecnología frente a tratamientos térmicos tradicionales. Las fracciones de huevo (clara, yema y huevo entero) tratadas con UV-C fueron analizadas en cuanto a los cambios de pH, color, estabilidad de lípidos (TBARS, colesterol y valor de peróxidos), efectos en las proteínas (oxidación proteica, DSC, SDS-PAGE), propiedades reológicas (viscosidad dinámica, comportamiento de flujo, viscosidad en función de la temperatura), propiedades funcionales (emulsionantes y espumantes), composición nutricional (vitaminas y minerales), composición de componentes saludables (carotenoides), y cito-genotoxicologia. Finalmente, la aceptación sensorial de los ovoproductos líquidos tratados por UV-C y de productos preparados con ovoproductos líquidos tratados por UV-C (mayonesa, bizcocho y pudin) fueron evaluadas por medio de pruebas triangulares y afectivas. El tratamiento con UV-C demostró ser una excelente alternativa a la pasteurización térmica. En microorganismos inoculados, se demostró una reducción de 5 Log tanto para Gram(+) como para Gram(-) en un equipo comercial para tratamientos en régimen continuo (UVivatec�). En tandas, los resultados también mostraron decrecimientos importantes en el recuento de microorganismos inoculados, aunque serían necesarios tiempos largos de tratamiento para producir una descontaminación comparable a la pasteurización térmica. Los ovoproductos líquidos tratados con UV-C fueron estables durante 8Mendes De Souza, P. (2012). Study of short-wave ultraviolet treatments (UV-C) as a non-thermal preservation process for liquid egg products [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/16696
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Veleba, Josef. "Přesnost metod detekce atriální fibrilace v EKG signálech." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2016. http://www.nusl.cz/ntk/nusl-242179.
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This thesis focuses on the issue of atrial fibrillation and the success of their detection in the ECG signal. It provides a description of electrical activity of the heart with the theoretical analysis of atrial fibrillation and methods for their detection. Additionally the work describes procedures for the implementation of three selected methods for the detection of atrial fibrillation in the MATLAB environment, presents the results of their tests on two atrial fibrillation signal databases and assesses the accuracy of each method.
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Renauld, Emmanuelle. "Les morphologies du thalamus, du corps géniculé latéral et de la radiation optique n'influencent pas les ondes alpha EEG." Mémoire, Université de Sherbrooke, 2015. http://hdl.handle.net/11143/6810.
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Résumé : Au repos, l'activité du cerveau d'un humain sain est caractérisée par de larges fluctuations dans la bande de fréquences de 8-13 Hz d'un électroencéphalogramme (EEG), connue sous le nom de bande alpha. Bien qu'il soit établi que son activité varie d'un individu à l'autre, peu d'études se sont intéressées à la façon dont elle peut être reliée aux variations morphologiques des structures du cerveau. Entre autres, on pense que le corps géniculé latéral (CGL) et ses fibres efférentes (la radiation optique) jouent un rôle clé sur l'activité alpha, bien qu'il n'est pas certain que leur forme ou leur grosseur contribuent à sa variabilité inter-individuelle. Considérant l'utilisation courante d'EEG dans la recherche fondamentale ou clinique, ce sujet est important, mais difficile à traiter vu les problèmes associés à une bonne segmentation du CGL et de la radiation optique. Pour cette raison, nous avons utilisé la résonance magnétique de diffusion (IRMd), la résonance magnétique fonctionnelle (IRMf) et l'EEG sur 20 sujets sains pour mesurer la structure et la fonction, respectivement. L'analyse de la structure a nécessité une nouvelle approche semi-automatique pour segmenter le CGL et la radiation optique, qui nous a permis de mesurer plusieurs variables, telles que le volume et la position. Ces mesures correspondent bien aux connaissances sur la morphologie de ces structures basées sur des études post-mortem, et pourtant, nous avons trouvé que leur variabilité inter-sujet n'influençait pas la puissance des ondes alpha ou leur fréquence-type (p>0.05). Ces résultats suggèrent que la variabilité alpha soit médiée par d'autres sources structurelles. Notre méthodologie pourra servir pour de futures recherches sur l'influence de l'anatomie sur la fonction en IRMf, tomographie par émission de positron (TEP), EEG, etc., ou pour améliorer les recherches cliniques sur la radiation optique.Abstract : At rest, healthy human brain activity is characterized by large electroencephalography (EEG) fluctuations in the 8-13 Hz range, commonly referred to as the alpha band. Although it is well known that EEG alpha activity varies across individuals, few studies have investigated how this may be related to underlying morphological variations in brain structure. Specifically, it is generally believed that the lateral geniculate nucleus (LGN) and its efferent fibres (optic radiation, OR) play a key role in alpha activity, yet it is unclear whether their shape or size variations contribute to its inter-subject variability. Given the widespread use of EEG alpha in basic and clinical research, addressing this is important, though difficult given the problems associated with reliably segmenting the LGN and OR. For this, we employed a multi-modal approach and combined diffusion magnetic resonance imaging (dMRI), functional magnetic resonance imaging (fMRI) and EEG in 20 healthy subjects to measure structure and function, respectively. For the former, we developed a new, semi-automated approach for segmenting the OR and LGN, from which we extracted several structural metrics such as volume, position and diffusivity. Although these measures corresponded well with known morphology based on previous post-mortem studies, we nonetheless found that their inter-subject variability was not significantly correlated to alpha power or peak frequency (p > 0.05). Our results therefore suggest that alpha variability may be mediated by an alternative structural source and our proposed methodology may in general help in better understanding the influence of anatomy on function.
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Souza, André Luís de Oliveira. "Métodos analíticos, numéricos e experimentais para o cálculo de ondas de impacto em meios líquidos /." Ilha Solteira : [s.n.], 2007. http://hdl.handle.net/11449/88875.
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Orientador: Geraldo de Freitas MacielBanca: João Batista Campos Silva
Banca: Márcio Benedito Baptista
Resumo: Este trabalho versa sobre ondas de gravidade geradas por impacto de massas sólidas em meio líquido. Vários ensaios com materiais granulares, simulando o deslizamento, foram conduzidos em um canal de ondas provido de rampa a montante, sobre a qual esferas de vidro e seixos rolados, de diâmetros distintos, após deslizarem, vinham impactar o meio líquido gerando ondas de submersão. O canal, localizado no Laboratório de Hidráulica e Hidrometria da UNESP - Ilha Solteira, apresenta as dimensões 0,30 m de largura, 0,50 m de altura e 10,00 m de comprimento. Os ensaios com lâmina d'água variando entre 0,13 m e 0,20 m foram executados no intuito de checar algumas propriedades desse complexo processo físico de geração de ondas, quais sejam: o campo de velocidades do material granular incidente (centro de massa e frente de deslizamento), utilizando recursos de cinematografia e tratamento de imagens; determinação de alturas de ondas através de sondas capacitivas micro-controladas; e, por fim, obtenção de velocidades orbitais na zona de geração, através de sondas ADV (Acoustic Doppler Velocimeter). Com o objetivo de validar modelo numérico desenvolvido por Maciel (1991) e aprimorado por Nascimento (2001), os ensaios experimentais subsidiaram o processo de validação do referido modelo, baseado nas equações de Serre, para o caso de materiais granulares, até então não contemplado por outros trabalhos citados na literatura. Foi também brevemente testado, o que requer aprofundamento em trabalho futuro, um modelo numérico lagrangeano, apresentado no Anexo III. Na seqüência, foi também realizada uma análise da transferência de energia do material granular incidente para o meio líquido, cujo principal objetivo era de avaliar o percentual de energia cinética do deslizamento que fora convertido em energias cinética e potencial da onda gerada... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: This work is about gravity waves generated by solid mass impact into liquid. Several essays with granular material, simulating a landslide, were conduced in a wave channel provided with an upstream ramp where glass spheres and pebbles (with two different diameter intervals) slide the ramp generating submersion waves. The wave channel is located at UNESP - Ilha Solteira's Hydraulics and Hydrometrics Laboratory. Its dimension is 0,30 m (width), 0,50 m (high) and 10,00 m (length). The depth of water was from 0,13 m up to 0,20 m. Some properties of the complex physic process of landslide generated waves were investigated: granular material's velocity field (trough cinematography method and image treatment); wave height was founded with micro controlled capacitance wave gauges; and orbital velocity was acquired by Acoustic Doppler Velocimeter (ADV) gauges. The main aim was to validate a numeric model developed by Maciel (1991) further improved by Nascimento (2001) for granular material generated waves. The experimental essays were essential to the validation of the Serre's equation based model for granular material (do not contemplated by other works in the literature). A lagrangean numeric model was briefly tested (Anexo III). The energy transfer of the granular material to waves was also analyzed with purpose to evaluate the fraction of the solid's kinematics energy was converted in wave's kinematics and potential energies. In the engineering context, this work brings a chapter with several analytic, semi-empiric and empiric methods of water wave's height estimation. They are based on geometric characteristics and slide's dynamics. Another chapter compares those methods.
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Castro, Simon Joseph. "T-wave morphology and atrio-ventricular conduction : insights from novel image-based models of the whole heart." Thesis, University of Manchester, 2015. https://www.research.manchester.ac.uk/portal/en/theses/twave-morphology-and-atrioventricular-conduction-insights-from-novel-imagebased-models-of-the-whole-heart(3626ead4-1cf0-4228-a70c-827b828e8f06).html.
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Cardiovascular disease is a leading cause of death in developed countries, and places a huge demand on healthcare services and economies across the globe. In this thesis computational models of the rabbit and mouse whole heart were developed and used to investigate a variety of phenomena related to cardiac electrophysiology. In part I, a heterogeneous family of single cell models was developed for the rabbit ventricles. The models were incorporated into a 3D anatomical reconstruction, and subsequently used to study the relationship between ventricular heterogeneity and the electrocardiographic T-wave. It was found that, in order of significance, apico-basal, inter-ventricular and transmural heterogeneity had a lead-dependent effect on the T-wave of the 12-lead electrocardiogram. Subsequently, a detailed model of the rabbit whole heart was developed using image data from X-ray computed tomography, from which detailed anatomical structures were segmented and myocardial architecture determined. The developed 3D whole heart model exhibited physiological fibre structure and experimentally justified patterns of activation. In part II, a mathematical model of the mouse atrioventricular node was developed. The model was validated by its ability to show physiological pacemaking and response to ion channel blocking. The model was subsequently adapted to consider the heterogeneous nature of the atrioventricular node, and incorporated into a 2D simplistic tissue model of the whole heart. The developed model exhibited physiological atrioventricular conduction, and provided insights into the nature of dual-pathway electrophysiology and the role of the funny current. Finally, an optimisation study was carried out for contrast enhancement of X-ray computed tomography, specifically for imaging the mouse heart, the results of which may be used to facilitate future high-throughput imaging of cardiac tissue.
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Ferreira, Fabiana de Oliveira. "Abordagem matemática de roll waves em escoamentos hiperconcentrados com superfície livre /." Ilha Solteira : [s.n.], 2007. http://hdl.handle.net/11449/88889.
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Orientador: Geraldo de Freitas MacielBanca: José Luiz Gasche
Banca: José Carlos Cesar Amorim
Resumo: Os escoamentos em superfície livre que ocorrem em canais inclinados, tanto em fluido Newtoniano quanto em fluido não-Newtoniano (hiperconcentrado), podem desenvolver instabilidades, tais como ondas em forma de ressalto hidráulico, com comprimentos bem definidos. Tais perturbações são denominadas Roll Waves. Essas ondas são comuns em canais artificiais, em lavas torrenciais e deslizamento de avalanchas. Neste trabalho, no plano teórico, é determinado um modelo matemático geral, com base nas equações de Navier- Stokes integradas na vertical, em cujo tensor de tensões é introduzido a reologia de Herschel- Bulkley. A velocidade média do escoamento é determinada levando-se em consideração que o escoamento apresenta um perfil de velocidade parabólico na região cisalhada (próximo ao fundo do canal) acoplado a um perfil linear na região não cisalhada (condição de plug), característico dos escoamentos de lamas e detritos. A partir do sistema de equações (conservação da massa e equação da quantidade de movimento) em variáveis adimensionais, uma análise de estabilidade linear é realizada, colocando em evidência as condições de formação dessas instabilidades, tanto em fluido hiperconcentrado como em fluido Newtoniano. Com as condições de formação de instabilidades estabelecidas, uma teoria analítica de Roll Waves permanente é imposta e um modelo matemático para geração de tais instabilidades é determinado. No plano numérico, utilizando a linguagem de programação Python, a validade do modelo é verificada, considerando que essas ondas são ajustadas por choques devido às singularidades existentes no modelo. Com a determinação das condições de choque e da velocidade de propagação da onda em um ponto crítico; pode-se observar a formação de Roll Waves em fluidos não Newtonianos com reologia de Herschel-Bulkley, Bingham, Power Law, como também em fluido Newtoniano.
Abstract: The flows in free surface that occur in sloping canals, such as Newtonian fluid as in non- Newtonian fluid (hyperconcentrated), they can develop instabilities, such as long waves in form of hydraulical jumps, with well defined lengths; these instabilities are called Roll Waves, more common in artificial canals, torrential spillways of dams, lava and avalanche landslide. This work, in the theoretical plan, a general mathematical model is determined, on the basis of the integrated Navier-Stokes equation in the vertical, of tensor tensions the rheology of Herschel-Bulkley is introduced. The average velocity of the flows is determined taking itself in consideration that the flows presents a parabolic profile of speed in the shear region (near of the floor of canal) connected to a linear profile in the region not shear (condition of plug), categorized as flows of mudflows and debris flows. From the system of equations (conservation of the mass and equation of the momentum) in adimensional variables, an analysis of linear stability is carried through, placing the conditions of formation of these instabilities, as much in hyperconcentrated fluid as in Newtonian fluid. With the conditions of formation of instabilities established, a analytical theory of permanent Roll Waves is imployed and a mathematical model for geration of such stabilities it's determined. In the numerical plan, using the computational consol Python, the validity of model is checked, considering of this waves are adjusted by shocks devided by the singularities existents in the model. With the determination of conditions of shock and the velocity of propagation of wave in a critical point; we can observe the formation of Roll Waves such in fluids non-Newtonians (Herschel- Bulkley, Bingham, Power law) as Newtonian fluids.
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Vieira, Adriana Silveira. "Um panorama sobre roll waves em escoamentos laminares e turbulentos com superfície livre /." Ilha Solteira : [s.n.], 2007. http://hdl.handle.net/11449/88890.
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Orientador: Geraldo de Freitas MacielBanca: André Luiz Seixlack
Banca: Luís Miguel Chagas da Costa Gil
Resumo: Os escoamentos na superfície livre que se processam sobre forte declividade podem desenvolver instabilidades ao cabo de tempo finito. Tais instabilidades aparecem sob formas de ondas tipo "hydraulic jumps" bem espaçados e são denominadas Roll Waves. Estas ondas, longas e periódicas, podem ser contínuas ou descontínuas; contínuas em problema Shallow Water viscoso e descontínuas para o caso não viscoso. Tal fenômeno pode ser observado tanto em escoamentos naturais como em canais artificiais e vertedouros de barragens. Tratando-se de escoamento de Fluidos não newtonianos, tal fenômeno pode ser visto facilmente em lavas torrenciais, avalanchas ou "debris flows". Nesta dissertação foram analisados matematicamente e numericamente o comportamento e as condições de existência para a formação de Roll Waves em escoamentos laminares e turbulentos. Em escoamentos turbulentos toma-se como referência os trabalhos realizados por Maciel (2001) numa reologia Binghamiana. Para escoamentos laminares, cita-se o trabalho de Mei (1994) em uma reologia tipo Power Law. No plano numérico, para escoamentos turbulentos, foram utilizadas rotinas do MATLAB® versão 6.5 e, para escoamentos laminares, rotinas em FORTRAN 90; onde pôde-se analisar e comparar resultados para diversas reologias. O foco desta dissertação foi tratar o problema Roll Waves como uma instabilidade na vizinhança do regime uniforme para Fluidos não newtonianos, em regimes turbulentos e laminares. A reologia tratada e representativa de diversos escoamentos na natureza foi a de Herschel Bulkley. A partir desta dissertação deixa-se, como perspectiva futura, um estudo mais aprofundado sob formação de ondas em fluidos hiperconcentrados tipo Herschel Bulkley com abordagem experimental a fim de validar resultados apontados nesta pesquisa.
Abstract: Flows that happen over strong slope with free surface can develop instabilities after some finite time. Such wave shaped instabilities appear in the flow and are of the type "hydraulic jumps" well spaced and they are called Roll Waves. Those waves are long and periodic, continuous or discontinuous, continuous in viscous Shallow Water problems, and discontinuous for the inviscid case. Roll Waves are uncommon in natural flows, but they are common in man made channels and dams spillway. For flows of non Newtonian fluids such phenomenon can be seen easily in lava torrent, avalanche and debris flow. In this work it were mathematically and numerically analyzed the behavior and the existence conditions for the generation of Roll Waves within laminar and turbulent flows. For turbulent flows it is taken as reference the works done by Maciel (2001) dealing with a Bingham rheology. For laminar flows the reference is the work done by Mei (1994) using a Power Law rheology. Numerically, for turbulent flows it were used MATLAB® 6.5 procedures and for laminar flows FORTRAN 90 procedures were developed. Using these reference procedures it was obtained compared and analyzed results for several rheologies. This work left as future perspective a deeper study about the generation of waves in hipper concentrated fluids such as Herschel Bulkley fluid, with an experimental approach aiming to validate results produced. The focus of this work was to treat the so called Roll Waves problem as an instability in the vicinity of the uniform flow regime for non Newtonian fluids under laminar and turbulent flow regimes. The Herschel Bulkley rheology that was treated in this work is representative of several flows that happen in nature.
Mestre
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Butts, Skyler. "Picture This: Exploring Mental Imagery’s Effect on Novice and Expert Golfers Putting under Pressure." Scholarship @ Claremont, 2016. http://scholarship.claremont.edu/cmc_theses/1243.
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This study proposes a series of 3 experiments to explore how the use of mental imagery affects expert vs. novice golfers differently, by comparing alpha and beta waves. In Experiment 1 experts and novices will putt under a pressure task or no pressure task. The researcher will analyze golfers’ putting success rate in addition to examining alpha and beta waves. Experiment 2 will expand upon the expected results of Experiment 1, focusing on experts’ and novices’ use of task-relevant and task-irrelevant mental imagery as pre-performance routines just before a putting task, with all conditions facing pressure. Finally, Experiment 3 will explore experts’ vs. novices’ use of task-relevant and task-irrelevant mental imagery the day before the pressure putting task. Researchers are expected to find increases in alpha wave activity to occur prior to the putting task in experts regardless of condition, which is consistent with the attention-arousal set theory’s concept of an optimal state of performance. Novices should display increases in alpha wave activity and reach their optimal state of performance when the type of mental imagery they use helps them relax, which should lead to a higher putting success rate.
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Pyles, Marcelo Damas. "Avaliação por ultrassonografia quantitativa do osso terceiro metacarpiano de equinos atletas tratados com ondas de choque extracorpóreas /." Botucatu : [s.n.], 2009. http://hdl.handle.net/11449/101032.
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Orientador: Ana Liz Garcia AlvesBanca: Carlos Alberto Hussni
Banca: Elisa Holthausen Caminoto
Banca: Luciane Rasera
Banca: Vânia Maria Vasconcelos Machado
Resumo: O objetivo deste estudo foi avaliar os efeitos da aplicação de ondas de choque extracorpóreas no osso terceiro metacarpiano de equinos hígidos através da determinação da elasticidade óssea. Para tanto, foram utilizados 20 equinos da raça Puro Sangue Inglês, machos e fêmeas, com dois anos de idade, clinicamente sadios e em início de treinamento, sendo selecionados quanto ao estado de higidez com especial atenção quanto à integridade do aparelho locomotor. No D0, dia zero do experimento, todos os animais foram submetidos à avaliação da elasticidade óssea realizada no osso terceiro metacarpiano. Os animais foram divididos aleatoriamente em dois grupos de dez animais em cada (Grupo Controle e Grupo Tratamento). A aplicação da terapia com ondas de choque extracorpóreas (ESWT) foi realizada no membro torácico direito dos animais do Grupo Tratamento, na região coincidente à da avaliação da elasticidade óssea e para tanto foi utilizado aparelho para terapia de ondas extracorpóreas com densidade de fluxo de energia de 0,15 mJ/mm2 e 2000 pulsos com sonda E6R20, com a característica do foco da onda de choque de 20mm. As aplicações da ESWT foram repetidas a cada 21 dias totalizando três sessões (D0, D21 e D42). A análise da determinação da elasticidade óssea, além do D0, foi realizada no 21o dia após a primeira aplicação, no 21o dia após a segunda aplicação e no 30o dia após a terceira aplicação de ESWT (D21, D42 e D72). A média da velocidade ultrassonográfica (SOS) diferiu entre os grupos no D21, D42 e D72, sendo que os animais do Grupo Tratamento apresentaram menor densidade mineral óssea após as aplicações da ESWT. Houve diferença também à análise da massa óssea (Z-Score) entre os grupos no D21 e D42, quando... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: The purpose of this study was to evaluate the effects of extracorporeal shock waves in third metacarpus bone from healthy horses by determination of bone elasticity. It were used 20 Thoroughbred horses, male and female, with two years old, clinically healthy and on top of training, selected as healthy state and special attention on the integrity of the locomotor system. At D0, day zero of the experiment, all animals were submitted to evaluation of bone elasticity held in the third metacarpus bone. The animals were randomly divided into two groups of ten animals (Control Group and Treatment Group). The application of extracorporeal shock wave therapy (ESWT) was performed on the right forelimb of the animals in the Treatment group in the same location evaluated for bone elasticity and extracorporeal therapy of waves was applied with 0.15mJ/mm2 energy flux density and 2000 pulses with E6R20 probe, with focus feature of the shock wave of 20mm. The applications of ESWT were repeated every 21 days, a total of three sessions (D0, D21 and D42). The analysis of bone elasticity determination was realized at D21, D42 and D72. The average speed ultrasound (SOS) differed between groups at D21, D42 and D72, and the animals from treatment group had lower bone mineral density after applications of ESWT. There was also difference in the analysis of bone mass (Z-Score) between the groups at D21 and D42, where animals from treatment group showed a significant decrease in bone mass. The risk of fracture were higher in animals from treatment group at D21. It was concluded that ESWT is able to promote change in bone mineral density.
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Gioso, Marilú Martins. "Eficiência de diferentes doses de acetato de fertirelina na sincronização da emergência da onda folicular e indução da ovulação em vacas leiteiras /." Botucatu : [s.n.], 2006. http://hdl.handle.net/11449/105963.
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Resumo: Vários produtos à base de GnRH são efetivos em protocolos de Inseminação Artificial em Tempo Fixo (IATF). Entretanto, o Acetato de Fertirelina é um análogo deste hormônio cujas informações sobre sua ação na dinâmica folicular dos bovinos são poucas, principalmente nas condições brasileiras. Este trabalho teve como objetivo comparar a eficiência de duas doses de Acetato de Fertirelina para sincronização da emergência da onda de desenvolvimento folicular e ovulação, em vacas leiteiras submetidas ao protocolo "Ovsynch". Utilizaram-se 77 vacas, a partir dos 60 dias pós-parto e escore corporal entre 2,5-4,0. Os animais apresentavam população folicular e corpo lúteo (CL) característico (Classe 1) ou ausência de CL, porém presença de pelo menos um folículo com diâmetro >10mm (Classe 2). As fêmeas foram distribuídas aleatoriamente em quatro tratamentos. Em conclusão, as concentrações séricas de progesterona e estradiol, taxas de sincronização, ovulação e prenhez demonstraram que o Acetato de Fertirelina foi eficiente em provocar a emergência da onda folicular e induzir a ovulação, nas doses de 50 ou 100mg, sugerindo que doses de 50mg de Fertirelina podem ser indicadas sem comprometimento nos resultados finais do programa.Abstract: Many similar products to GnRH are effective in protocols of fixed timed artificial insemination (FTAI). However, Fertirelin Acetate is an analog of this hormone whose information about action in the bovine follicular dynamics is inconsistent, mainly in brazilian conditions. Therefore, the objective of this work was to compare the efficiency of two doses of Fertirelin used for synchronization of follicular wave emergence and ovulation, in dairy cows submitted to "Ovsynch" protocol. Seventy seven lactating dairy cows, on over of 60 days postpartum and body score of 2.5 to 4.0. The animals presenting a reasonable number of follicles either a presence of CL (group 1) or without CL but at last =10 mm follicles (group 2). The females were randomly distributed in four treatments. The pregnancy rates were also similar (P>0.05) with mean of 28.37%. In conclusion, Progesterone and Estradiol concentrations, follicular wave synchronization, induction of ovulation and pregnant rates demonstrate that Fertirelin was efficient in inducing a new follicular wave emergency, as well as the induction of the ovulation at the end of the protocol, using the dose of either 50mg or 100 mg, suggesting that 50mg of Fertirelin can be useful without compromising the final results.
Orientador: Eunice Oba
Coorientador: Carlos Antonio de Carvalho Fernandes
Banca: Gilson Toniollo
Banca: Alício Martins Júnior
Banca: Maria Inêz Lenz Souza
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Žiemys, Tadas. "Paveikslų įvertinimo prognozavimo tyrimas naudojant Neurosky Mindwave įrenginį." Master's thesis, Lithuanian Academic Libraries Network (LABT), 2012. http://vddb.laba.lt/obj/LT-eLABa-0001:E.02~2012~D_20120620_113900-37800.
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Darbo pradžioje apžvelgiamos vartotojo sąsajos, kokios yra ateities perspektyvos smegenų-kompiuterio sąsajoms, kokie tyrimai atliekami šioje srityje. Aprašoma, kas yra elektroencefalografija (EEG), kaip atsiranda elektriniai impulsai smegenyse ir ką nagrinėja neuroestetikos mokslas. Magistrinio darbo tikslas buvo ištirti, kokiu tikslumu galima prognozuoti, ar subjektui patiks paveikslas. Prognozės yra atliekamos iš subjekto EEG signalų, kurie yra gaunami naudojant Neurosky MindWave įrenginį. Duomenų klasifikavimui yra naudojamas vienasluoksnis neuroninis tinklas sukurtas su MATLAB programine įranga. Darbo metu buvo sukurta iPad kompiuteriui skirta programa, kuri vaizduoja stimulus ir įrašinėja EEG duomenis iš Neurosky MindWave įrenginio. Stimulams yra naudojami įvairių laikotarpių, skirtingų autorių tapybos darbai. Tyrimas parodė, kad įmanoma prognozuoti vartotojo pasirikimą tiksliau negu atsitiktinumas. Klasifikatoriaus tikslumas daugiausia duomenų turinčiam subjektui siekia iki 74%. Tuo tarpu apmokant dirbtinį neuroninį tinklą visų subjektų duomenimis, klasifikatoriaus tikslumas yra labai panašus į atsitiktinumą – 55%.The aim of this thesis is to study the accuracy of prediction of subject’s preferences when observing various paintings. Prediction is caried out using subject’s EEG signals which are produced using Neurosky MindWave device. To clasify data one layer artificial neuron network is used. The network is a MATLAB application. For this study application for iPad is created. This application represents and records EEG data from Neurosky MindWave device. In order to produce stimuli subjects are presented with paintings by various artists from different epoches. The study showed that it is posible to predict the preference with accuracy greater than a mere chance. The classifier’s accuracy for the subject with most data is up to 74% (average 64.58%). For other subjects’ the accuracy of prediction of 58% is reached.