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Physiological Attunement and Influence in Couples Therapy: Examining the Roots of Therapeutic PresenceBernards, Julia Campbell 01 June 2017 (has links)
Extensive interdisciplinary common factor research has identified the therapeutic relationship as a consistent factor influencing therapeutic outcomes. We use Polyvagal and Interpersonal Neurobiology (IPNB) theories to guide an examination of the physiological mechanisms at work in the therapeutic relationship. Both Polyvagal and IPNB theories provide understandings about how humans are neurophysiologically wired for social connection. Each points to a sense of safety as being essential for meaningful connection to occur and clarifies that physiological attunement is an observable indicator of interpersonal connection. In this study, we use these theories to guide an examination of therapist physiological influence on clients in couple therapy, using continuous in-session data collection of respiratory sinus arrhythmia (RSA) for 22 heterosexual married couples and their therapist. Data were modeled in a multi-level path analytic framework to account for within-individual and within-couple effects. Results indicated that therapist RSA does not significantly predict lagged client RSA. A discussion of potential limitations, suggestions for therapists and recommendations for future study is included.
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Parturition of Mule Deer in Southern Utah: Management Implications and Habitat SelectionFreeman, Eric D 01 March 2014 (has links)
Mule deer (Odocoileus hemionus) are an ecologically, economically, and socially important species across much of the western United States. As such, populations and habitat are intensely managed by state game agencies. However, populations have been declining in recent decades and several factors have been implicated (e.g., climate, predation, competition, and habitat availability). Population dynamics of mule deer are driven by a combination of survival of adults and juveniles and reproductive rates. While adult female mule deer typically have consistently high annual survival rates (85% annually), juveniles are more easily affected by stressors (biotic and abiotic conditions) and therefore their annual survival rates are generally low and highly variable. In an effort to better understand the effects of management on—and the habitat needs for—reproduction and recruitment, we examined the potential effects of male-biased harvest on recruitment in populations of mule deer and the selection of sites for parturition by mule deer females. Changes in buck:doe ratio due to male-biased harvest may alter rates of pregnancy, timing of parturition, and synchrony of parturition if inadequate numbers of males are present to fertilize females during their first estrous cycle. If rates of pregnancy or timing of parturition are influenced by decreased buck:doe ratios, recruitment may be reduced. This results from fewer births, later parturition (resulting in lower survival of fawns), and a less synchronous parturition period (increasing the proportion of neonates exposed to predation). Our objectives were to compare rates of pregnancy, timing of parturition, and synchrony of parturition between exploited populations of mule deer with relatively high (Piceance Basin) and relatively low (Monroe Mountain) buck:doe ratios. We determined rates of pregnancy via ultrasonography and timing of parturition via expulsion of vaginal implant transmitters. We found no differences in rates of pregnancy, timing of parturition, or synchrony of parturition between Monroe Mountain and Piceance Basin. This suggests that the relatively low buck:doe ratios typical of heavily harvested populations do not have unintended or indirect impacts on population dynamics because recruitment remains unaffected. Because neonate ungulates are most vulnerable to predation during parturition and shortly thereafter, selecting sites for parturition can have direct fitness consequences. We investigated the selection of sites for parturition by mule deer. We utilized vaginal implant transmitters to identify sites of parturition. We then obtained and compared macro- and micro-habitat features between sites of parturition and associated random sites. Parturitient females selected sites based on topography, habitat-type, and obscurity. Enhanced understanding of habitat variables that are selected for parturition provides insight into the life history or behavior of a species and allows managers to ensure that suitable habitat is available for this stage of life-cycles.
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Behavioural Endocrinology of Breeding Adelie Penguins (Pygoscelis adeliae)Ninnes, Calum Edward January 2008 (has links)
Measuring hormonal changes is vital for understanding how the social and physical environment influences behaviour, reproduction and survival. Various methods of hormone measurement exist, potentially explaining variation in results across studies; methods should be cross validated to ensure they correlate. I directly compare faecal and plasma hormone measurements (Chapter 2), and use the most suitable endocrine measure to test the Darling hypothesis (Chapter 3) - that breeding is hastened and synchronized in larger colonies due to increased social stimulation (mediated by the endocrine system). Blood and faecal samples were simultaneously collected from individual Adelie penguins (Pygoscelis adeliae) for comparison, and assayed for testosterone and corticosterone (or their metabolites). Sex differences and variability within each measure, and correlation of values across measures were compared. For both hormones, plasma samples showed greater variation than faecal samples. Males had higher corticosterone levels than females, but the difference was only significant in faecal samples. Plasma testosterone, but not faecal testosterone, was significantly higher in males than females. Correlation between sample types was poor overall, and weaker in females than in males; perhaps because measures from plasma represent hormones that are both free and bound to globulins, whereas measures from faeces represent only the free portion. Faecal samples also represent a cumulative measure of hormones over time, as opposed to a plasma 'snapshot' concentration. Faecal sampling appears more suitable for assessing baseline hormone levels. In the second study I examined, over two seasons, whether the timing of breeding varied with colony size; larger colonies present occupants with higher levels of social stimulation and are predicted to show earlier, more synchronous breeding. Baseline faecal hormone levels throughout the breeding season, and survival, were measured to investigate possible proximate and ultimate mechanisms for the results. The influence of environmental variability was examined, by relating the timing of breeding, survival, and endocrine changes to sea ice conditions. Colony size did not influence the timing or synchrony of breeding, survival, or hormone levels within years; perhaps because colonies in an Adelie rookery are not independent from the 'social environment' of adjacent colonies. Across years, synchrony in the smaller rookery was higher than in the larger rookery. The scale of these comparisons may exceed the applicability of the Darling hypothesis. Therefore, no support was found for the Darling hypothesis, at the colony or rookery level, in this species. Higher corticosterone metabolite and lower sex hormone levels in the first season correlated to later breeding and lower survival compared to the second season. This is likely due to the persistence of extensive sea ice conditions late into the first season. Researchers should take care in selecting the most appropriate method of hormone measurement for their question. Future studies testing the Darling hypothesis must carefully select their definition of a colony (i.e. a truly isolated social unit) and the scale at which the hypothesis is tested. Combining endocrine measurements with behavioural, survival, and environmental information allows for a more comprehensive interpretation of animal ecology.
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Missing Links the role of phase synchronous gamma oscillations in normal cognition and their dysfunction in schizophreniaHaig, Albert Roland January 2002 (has links)
SUMMARY Introduction: There has recently been a great deal of interest in the role of synchronous high-frequency gamma oscillations in brain function. This interest has been motivated by an increasing body of evidence, that oscillations which are synchronous in phase across separated neuronal populations, may represent an important mechanism by which the brain binds or integrates spatially distributed processing activity which is related to the same object. Many models of schizophrenia suggest an impairment in the integration of brain processing, such as a loosening of associations, disconnection, defective multiple constraint organization, or cognitive dysmetria. This has led to recent speculation that abnormalities of high-frequency gamma synchronization may reflect a core dimension of the disturbance underlying this disorder. However, examination of the phase synchronization of gamma oscillations in patients with schizophrenia has never been previously undertaken. Method: In this thesis a new method of analysis of gamma synchrony was introduced, which enables the phase relationships of oscillations in a specific frequency band to be examined across multiple scalp sites as a function of time. This enabled, for the first time, the phase synchronization of gamma oscillations across widespread regions, to be studied in electrical brain activity measured at the scalp in humans. Gamma synchrony responses were studied in electroencephalographic (EEG) data acquired during a commonly employed conventional auditory oddball paradigm. The research consisted of two sets of experiments. In the first set of experiments, data from 100 normal subjects, consisting of 10 males and 10 females in each age decade from 20 to 70, was examined. These experiments were designed to characterize the gamma synchonizations that occurred in response to target and background stimuli and their functional significance in normal brain activity, and to exclude the possibility of these findings being due to electromyogram (EMG) or volume conduction artifact. The examination of functional significance involved the development of an additional new analysis technique. In the second set of experiments, data acquired from 35 patients with schizophrenia and 35 matched normal controls was analyzed. The purpose of these experiments was to determine whether patients showed disturbances of gamma synchrony compared to controls, and to establish the relationship of any such disturbances to medication levels, symptom profiles, duration of illness, and a range of psychophysiological variables. Results: In the 100 normals, responses to target stimuli were characterized by two bursts of synchronous gamma oscillations, an early (evoked) and a late (induced) synchronization, with different topographic distributions. Only the early gamma synchronization was seen in response to background stimuli. The main variable modulating the magnitude of these gamma synchronizations from epoch to epoch was pre-stimulus EEG theta (3-7 Hz) and delta (1-3 Hz) power. Early and late gamma synchrony were also associated with N1 and P3 ERP component amplitude across epochs. Across subjects, the early gamma synchronization was associated with shorter latency of the ERP components P2, N2 and P3, smaller amplitude of N1 and P2, and smaller pre-stimulus beta power. The control analyses showed that these gamma responses were specific to a narrow frequency range (37 to 41 Hz), and were not present in adjacent frequency bands. The responses were not generated by EMG contamination or volume conduction. In the 35 patients with schizophrenia, significant abnormalities of both the early and late synchronizations were observed compared to the 35 normal controls, with distinctive topographic characteristics. In general, early gamma synchrony was increased in patients compared to controls, and late gamma synchrony was decreased. These gamma synchrony disturbances were not related to medication level or the four summed symptom profile scores (positive, negative, general and total). They were, however, associated with duration of illness, becoming less severe the longer the patient had suffered from the disorder. The disordered gamma synchrony in patients was not secondary to abnormalities in other psychophysiological variables, but appeared to represent a primary disturbance. Discussion: The early synchronization may relate to the binding of object representations in early sensory processing, or, given that a constant inter-stimulus interval was employed, may be anticipatory and related to active memory. The late response is probably involved in binding in relation to activation of the internal contextual model involved in late expectancy/contextual processing (context updating or context closure) for target stimuli. The across epochs effects may relate to whether the focus of attention immediately prior to stimulus presentation is internal or is directed at the task. The across subjects effects suggest that a larger magnitude of the early gamma synchronization might indicate that the subject maintains a more stable and less ambiguous internal representation of the environment, that reduces the complexity of input and facilitates target/background discrimination and subsequent processing. The early gamma synchronization findings in patients with schizophrenia suggest that anticipatory processing involving active memory and forward-prediction of the environment is subject to over-binding or the formation of inappropriate associations. The late synchronization disturbances may reflect a fragmentation of contextual processing, and an inability to maintain contextual models of the environment intact over time. Conclusion: This research demonstrates the potential importance of integrative network activity as indexed by gamma phase synchrony in relation to normal cognition, and the possible broad relevance of such activity in psychiatric disorders. In particular, the application in this study to patients with schizophrenia showed that an impairment of brain integrative activity (missing links) might be a key feature of this illness.
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Arts'Codes: A New Methodology for the Development of Real-Time Embedded Applications for Control SystemsTeitelbaum, Aryeh Roberto, a_hay@jct.ac.il January 2007 (has links)
Embedded real-time applications have to allow interaction between the control computer and the controlled environment. Controlling the environment requires in particular to take into account its time constraints and critical logical conditions. One of the main programmer efforts in real-time application's development is to trace the incoming events, and to perform reactions based on the current system status, according to the application requirements. All this have to be handled, although external events may come in the middle of a critical reaction, which may disturb it. This problem involves two difficulties: X The cognitive efforts to percept the problem, and consequently to express the solution. X The correct translation of this solution to code. Two requirements were defined in this research in order to achieve high-quality performance: clearness and robustness, clearness in the design, and robustness in the execution. In this work the author proposes a methodology and a tool for real-time application's development that uses or implies an innovated form of design based on natural-cognitive researches. This design method has clear compilation's rules to produce an Object-Oriented light-code, suitable for embedded platforms. These compilation's rules introduce to the code implicit security and synchronization's elements, to support robust execution. In this methodology, clear development phases were defined, using a high-degree of reuse and even polymorphism, which were emphasized in the research. Several existing ideas were improved/adapted and synthesized together with the author's innovation, creating the Arts'Codes method for real-time application development. The work includes cognitive evaluations, assuring the natural skills of the design. Arts'Codes method proposes a natural VPL (Visual Programming Language) for real-time applications, based on hierarchic components. This VPL is built on a minimum of diagrams: one for the static architecture and one for the dynamic behaviour, with a similar restricted notation at all levels. These two diagrams (static architecture and dynamic behaviour) are interleaved in a unified view. This method was implemented by building a suitable graphic editor, which automatically compiles the applications diagrams in a light and robust Object-Oriented code (based on Parallel Automata FSM), and by building an execution compact software platform. Furthermore, the parallel automata FSM are translated automatically in PTL temporal formula defining the goals and the behaviours of the components, permitting to prove a-priory that the components behaviours are consistent to their goals. The execution platform is based on a restricted implementation of the synchrony hypothesis and on a powerful model of execution: the parallel automata FSM. These Parallel Automata describe the dynamic behaviours of the components and allows implementing run-time exceptions handling too. In addition, the research proposes a tri-processor execution hardware platform, which supports a hybrid synchronous/multi-threading execution. This method will contribute to versatile, clear and robust real-time application's development.
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A Prescription for Partial SynchronySastry, Srikanth 2011 May 1900 (has links)
Algorithms in message-passing distributed systems often require partial synchrony to tolerate crash failures. Informally, partial synchrony refers to systems where timing bounds on communication and computation may exist, but the knowledge of such bounds is limited. Traditionally, the foundation for the theory of partial synchrony has been real time: a time base measured by counting events external to the system, like the vibrations of Cesium atoms or piezoelectric crystals.
Unfortunately, algorithms that are correct relative to many real-time based models of partial synchrony may not behave correctly in empirical distributed systems. For example, a set of popular theoretical models, which we call M_*, assume (eventual) upper bounds on message delay and relative process speeds, regardless of message size
and absolute process speeds. Empirical systems with bounded channel capacity and bandwidth cannot realize such assumptions either natively, or through algorithmic
constructions. Consequently, empirical deployment of the many M_*-based algorithms risks anomalous behavior.
As a result, we argue that real time is the wrong basis for such a theory. Instead, the appropriate foundation for partial synchrony is fairness: a time base measured
by counting events internal to the system, like the steps executed by the processes. By way of example, we redefine M_* models with fairness-based bounds and provide algorithmic techniques to implement fairness-based M_* models on a significant subset of the empirical systems. The proposed techniques use failure detectors — system
services that provide hints about process crashes — as intermediaries that preserve the fairness constraints native to empirical systems. In effect, algorithms that are correct in M_* models are now proved correct in such empirical systems as well.
Demonstrating our results requires solving three open problems. (1) We propose the first unified mathematical framework based on Timed I/O Automata to specify empirical systems, partially synchronous systems, and algorithms that execute within the aforementioned systems. (2) We show that crash tolerance capabilities of popular distributed systems can be denominated exclusively through fairness constraints. (3) We specify exemplar system models that identify the set of weakest system models to implement popular failure detectors.
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Towards a Brain-inspired Information Processing System: Modelling and Analysis of Synaptic DynamicsEl-Laithy, Karim 12 January 2012 (has links) (PDF)
Biological neural systems (BNS) in general and the central nervous system (CNS) specifically
exhibit a strikingly efficient computational power along with an extreme flexible and adaptive basis
for acquiring and integrating new knowledge. Acquiring more insights into the actual mechanisms
of information processing within the BNS and their computational capabilities is a core objective
of modern computer science, computational sciences and neuroscience. Among the main reasons
of this tendency to understand the brain is to help in improving the quality of life of people suffer
from loss (either partial or complete) of brain or spinal cord functions. Brain-computer-interfaces
(BCI), neural prostheses and other similar approaches are potential solutions either to help these
patients through therapy or to push the progress in rehabilitation. There is however a significant
lack of knowledge regarding the basic information processing within the CNS. Without a better
understanding of the fundamental operations or sequences leading to cognitive abilities, applications
like BCI or neural prostheses will keep struggling to find a proper and systematic way to
help patients in this regard. In order to have more insights into these basic information processing
methods, this thesis presents an approach that makes a formal distinction between the essence
of being intelligent (as for the brain) and the classical class of artificial intelligence, e.g. with
expert systems. This approach investigates the underlying mechanisms allowing the CNS to be
capable of performing a massive amount of computational tasks with a sustainable efficiency and
flexibility. This is the essence of being intelligent, i.e. being able to learn, adapt and to invent.
The approach used in the thesis at hands is based on the hypothesis that the brain or specifically a
biological neural circuitry in the CNS is a dynamic system (network) that features emergent capabilities.
These capabilities can be imported into spiking neural networks (SNN) by emulating the
dynamic neural system. Emulating the dynamic system requires simulating both the inner workings
of the system and the framework of performing the information processing tasks. Thus, this
work comprises two main parts. The first part is concerned with introducing a proper and a novel
dynamic synaptic model as a vital constitute of the inner workings of the dynamic neural system.
This model represents a balanced integration between the needed biophysical details and being
computationally inexpensive. Being a biophysical model is important to allow for the abilities of
the target dynamic system to be inherited, and being simple is needed to allow for further implementation
in large scale simulations and for hardware implementation in the future. Besides, the
energy related aspects of synaptic dynamics are studied and linked to the behaviour of the networks
seeking for stable states of activities. The second part of the thesis is consequently concerned with
importing the processing framework of the dynamic system into the environment of SNN. This
part of the study investigates the well established concept of binding by synchrony to solve the information binding problem and to proposes the concept of synchrony states within SNN. The
concepts of computing with states are extended to investigate a computational model that is based
on the finite-state machines and reservoir computing. Biological plausible validations of the introduced
model and frameworks are performed. Results and discussions of these validations indicate
that this study presents a significant advance on the way of empowering the knowledge about the
mechanisms underpinning the computational power of CNS. Furthermore it shows a roadmap on
how to adopt the biological computational capabilities in computation science in general and in
biologically-inspired spiking neural networks in specific. Large scale simulations and the development
of neuromorphic hardware are work-in-progress and future work. Among the applications
of the introduced work are neural prostheses and bionic automation systems.
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Missing Links the role of phase synchronous gamma oscillations in normal cognition and their dysfunction in schizophreniaHaig, Albert Roland January 2002 (has links)
SUMMARY Introduction: There has recently been a great deal of interest in the role of synchronous high-frequency gamma oscillations in brain function. This interest has been motivated by an increasing body of evidence, that oscillations which are synchronous in phase across separated neuronal populations, may represent an important mechanism by which the brain binds or integrates spatially distributed processing activity which is related to the same object. Many models of schizophrenia suggest an impairment in the integration of brain processing, such as a loosening of associations, disconnection, defective multiple constraint organization, or cognitive dysmetria. This has led to recent speculation that abnormalities of high-frequency gamma synchronization may reflect a core dimension of the disturbance underlying this disorder. However, examination of the phase synchronization of gamma oscillations in patients with schizophrenia has never been previously undertaken. Method: In this thesis a new method of analysis of gamma synchrony was introduced, which enables the phase relationships of oscillations in a specific frequency band to be examined across multiple scalp sites as a function of time. This enabled, for the first time, the phase synchronization of gamma oscillations across widespread regions, to be studied in electrical brain activity measured at the scalp in humans. Gamma synchrony responses were studied in electroencephalographic (EEG) data acquired during a commonly employed conventional auditory oddball paradigm. The research consisted of two sets of experiments. In the first set of experiments, data from 100 normal subjects, consisting of 10 males and 10 females in each age decade from 20 to 70, was examined. These experiments were designed to characterize the gamma synchonizations that occurred in response to target and background stimuli and their functional significance in normal brain activity, and to exclude the possibility of these findings being due to electromyogram (EMG) or volume conduction artifact. The examination of functional significance involved the development of an additional new analysis technique. In the second set of experiments, data acquired from 35 patients with schizophrenia and 35 matched normal controls was analyzed. The purpose of these experiments was to determine whether patients showed disturbances of gamma synchrony compared to controls, and to establish the relationship of any such disturbances to medication levels, symptom profiles, duration of illness, and a range of psychophysiological variables. Results: In the 100 normals, responses to target stimuli were characterized by two bursts of synchronous gamma oscillations, an early (evoked) and a late (induced) synchronization, with different topographic distributions. Only the early gamma synchronization was seen in response to background stimuli. The main variable modulating the magnitude of these gamma synchronizations from epoch to epoch was pre-stimulus EEG theta (3-7 Hz) and delta (1-3 Hz) power. Early and late gamma synchrony were also associated with N1 and P3 ERP component amplitude across epochs. Across subjects, the early gamma synchronization was associated with shorter latency of the ERP components P2, N2 and P3, smaller amplitude of N1 and P2, and smaller pre-stimulus beta power. The control analyses showed that these gamma responses were specific to a narrow frequency range (37 to 41 Hz), and were not present in adjacent frequency bands. The responses were not generated by EMG contamination or volume conduction. In the 35 patients with schizophrenia, significant abnormalities of both the early and late synchronizations were observed compared to the 35 normal controls, with distinctive topographic characteristics. In general, early gamma synchrony was increased in patients compared to controls, and late gamma synchrony was decreased. These gamma synchrony disturbances were not related to medication level or the four summed symptom profile scores (positive, negative, general and total). They were, however, associated with duration of illness, becoming less severe the longer the patient had suffered from the disorder. The disordered gamma synchrony in patients was not secondary to abnormalities in other psychophysiological variables, but appeared to represent a primary disturbance. Discussion: The early synchronization may relate to the binding of object representations in early sensory processing, or, given that a constant inter-stimulus interval was employed, may be anticipatory and related to active memory. The late response is probably involved in binding in relation to activation of the internal contextual model involved in late expectancy/contextual processing (context updating or context closure) for target stimuli. The across epochs effects may relate to whether the focus of attention immediately prior to stimulus presentation is internal or is directed at the task. The across subjects effects suggest that a larger magnitude of the early gamma synchronization might indicate that the subject maintains a more stable and less ambiguous internal representation of the environment, that reduces the complexity of input and facilitates target/background discrimination and subsequent processing. The early gamma synchronization findings in patients with schizophrenia suggest that anticipatory processing involving active memory and forward-prediction of the environment is subject to over-binding or the formation of inappropriate associations. The late synchronization disturbances may reflect a fragmentation of contextual processing, and an inability to maintain contextual models of the environment intact over time. Conclusion: This research demonstrates the potential importance of integrative network activity as indexed by gamma phase synchrony in relation to normal cognition, and the possible broad relevance of such activity in psychiatric disorders. In particular, the application in this study to patients with schizophrenia showed that an impairment of brain integrative activity (missing links) might be a key feature of this illness.
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Dinâmica de grafoelementos do sono e seus impactos na neurofisiologia de pacientes com apneia obstrutiva através de sinais de eletroencefalografia / Sleep graphoelements dynamics and its impact on the neurophysiology of patients with obstructive sleep apnea through electroencephalography signalsSouza, Rafael Toledo Fernandes de [UNESP] 10 March 2016 (has links)
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Previous issue date: 2016-03-10 / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / O sono (do latim, somnus) é um período que apresenta uma atividade fisiológica característica, que pode ser registrada com o EEG. Algumas ondas em um sinal de EEG são vistas apenas durante o sono, como os fusos do sono e complexos K. O fuso é um dos elementos mais bem conhecidos no estudo do sono. No presente estudo serão estudados fusos globais e potenciais complexos K, os quais são observados simultaneamente em todos os canais de EEG. Para isto, um novo método de investigação foi proposto, que estuda tanto o envelope do sinal quanto a fase/frequência de cada fuso. Através da análise da fase do fuso global, foi mostrado que 90% dos fusos de indivíduos saudáveis sincronizam com um tempo de latência de 0,11s. O método também avalia a frequência de modulação (chirp) de fusos globais, e foi averiguado que não há correlação entre o chirp destes fusos e sua sincronização. Através do estudo do envelope do sinal juntamente com a implementação de um modelo de propagação isotrópico, foi possível estimar a origem do fuso e sua velocidade de propagação. Os resultados obtidos indicam que através desta abordagem simples e não invasiva é possível determinar, com uma precisão razoável, o local de origem dos fusos do sono, e sua velocidade estimada de propagação de 0,12m/s. Os potenciais complexos K detectados foram usados para avaliar a robustez do método desenvolvido, e apresentaram frequências, durações e amplitudes dentro das faixas esperadas para complexos K. A velocidade do propagação encontrada para os potenciais complexos K foi de 0,05m/s, menor do que a dos fusos do sono. Os potenciais complexos K mostraram ter uma tendência de sincronização parcial, propriedade esta descrita para os complexos K na literatura. O método desenvolvido também foi aplicado em indivíduos com Apneia Obstrutiva do Sono (AOS). A maioria dos parâmetros analisados não apresentaram diferenças significativas entre indivíduos saudáveis e com AOS; exceto que, em indivíduos com AOS, a duração da sincronização apresentou um valor 34,18% menor, e a posição de origem dos fusos apresentou dois focos diferentes. Desta maneira, conclui-se que o método desenvolvido foi aplicado com sucesso nos grafoelementos avaliados, pois consegue recuperar as informações esperadas, e pode ser útil como uma ferramenta diagnóstica não invasiva. / Sleep (derived from the Latim, somnus) is a brain state with distinct physiological activity that can be investigated by EEG evaluation. Some waves are unique in sleep EEG such as sleep spindles and K complexes. Spindles are one of the best known elements in sleep studies.
In this work we considered global spindles and K complexes, which are spindles that are observed simultaneously in all EEG channels. We propose a method that investigates both the signal envelope and phase/frequency of each global spindle. By analysing the spindle phase we showed that 90% of spindles in healthy subjects synchronize with a median latency time of 0.11 s. The method also measured the frequency slope (chirp) of global spindles and found that global spindle chirp and synchronization are not correlated. By investigating the signal envelopes and implementing a homogeneous and isotropic propagation model, we could estimate both the signal origin and velocity in global spindles. Our results indicate that this simple and non-invasive approach could determine with reasonable precision the spindle origin, and allowed us to estimate a signal speed of 0.12 m/s.
Potential K complexes are used to assess the robustness of developed method and shows that frequencies, durations and amplitudes within the K complex expected range. Propagation velocity in potential K complexes are around 0.05 m/s which is lower than spindles velocity. Partial synchronization tendencies were detected in potential K complex, a propriety described for K complex in the literature.
Obstructive Sleep Apnea (OSA) subjects were also assessed by our method. The majority of analysed parameters do not present significant difference between healthy and OSA subjects except by synchronization duration (34.18% lower in OSA) and two distinct focal points in OSA spindle origin.
The proposed methodology retrieved the expected results, obtained by EEG analysis and other more complex techniques and our results indicate that it can be used as a diagnosis tool and to explore other sleep phenomena, such as K complexes. / FAPESP: 2012/22413-2
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A voz em performance: uma abordagem sincrônica de narrativas e versos da cultura oral pantaneiraFernandes, Frederico Augusto Garcia [UNESP] 05 May 2003 (has links) (PDF)
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fernandes_fag_dr_assis.pdf: 1284451 bytes, checksum: cf6d97ecf9ce82a56850a7d557f3df33 (MD5) / Esta tese compreende um estudo da poesia oral pantaneira no momento de sua atualização, ou seja, durante a performance. Para tanto, ela se divide em três partes principais. Na primeira, com base em relatos de viagem, foram identificados embates discursivos entre o narrador e o viajante. A partir desses embates, foi demonstrado como, durante a performance, a presença do auditório exige do narrador uma postura frente àquilo que conta, ou seja, como ele cria uma identidade, que se manifesta pelo discurso da narrativa. Outro ponto discutido diz respeito ao registro da poesia oral pelo viajante, em que enfatizei como elementos ligados à performance foram ignorados e como a transcrição interfere na compreensão do texto oral. Na segunda parte, foram analisados os aspectos discursivos da narrativa oral. Constatei que o narrador cria uma autoridade (relação frente ao auditório) e autoria (atualização do texto que ouviu), pelas quais ele engendra um discurso identitário. A questão das variáveis e invariantes no texto oral foi estudada na terceira parte. Assim, detive-me no estudo das narrativas de enterro pantaneiras. Identifiquei elementos invariantes (origem, anunciação, marcação, provação, desenlace), que congregam algumas variáveis (tipos de origem, formas diferenciadas de anunciação, etc.). Além disso, as narrativas se reorganizam mudando de significado, como constatei com o protoconto, a explicativa, o logro e a descritiva. O último capítulo tratou da performance, em que foi analisada a manifestação da narrativa na performance e, também, alguns dos mecanismos que o narrador emprega para persuadir o seu auditório. Os estudos assim divididos visam a dar uma visão sincrônica da poesia oral, pois partem do texto oral em seu espaço de constituição, levando em conta a voz (identidade e ruído) do narrador. / This thesis contains an oral poetry study at the moment of its updating (sometimes subtractions are possible), that is to say, during the performance. For clarification's sake, it is divided in three main parts. In the first part, I identified the discoursive clashes between the narrator and the foreign traveler, based on travelers' reports. After that, it was demonstrated that the audience presence requires from the narrator, during the performance, an attitude about what he tells, i.e., an identity creation manifested by the narrative discourse. Another item is about the oral poetry recorded by the traveler. At this point, I emphasized that some performance features were ignored and that the transcription interferes in oral text comprehension. In the second part, the oral narrative discursive aspects were analyzed. I verified that the narrator creates an authority (the relationship face the audience) and an authorship (the listened text update) by which he engenders an identity discourse. The matter of variables and invariables was studied in the third part. Thus, I detained myself in the study of burial pantaneira narrative. I identified invariable elements (origin, annunciation, marking, probation, epilogue) that have some variables (kinds of origin, different forms of annunciation, etc.). Besides, the narratives reorganize themselves by changing their meanings such as the prototale, the explicative, the bluff and the descriptive, according to my verification. In the last chapter, I discussed the performance. I also analyzed the narrative manifestation in the performance and some of the narrator's mechanisms used to persuade his audience. Divided this way, the studies intend to make a synchronic approach of oral poetry, because they depart from oral text in its composition space taking into consideration the narrator's voice (identity and noise)
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