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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
421

Behavioral Inhibition/Activation and Autonomic Control of the Heart: Extending the Autonomic Flexibility Model

Christie, Israel C. 24 May 2005 (has links)
The autonomic flexibility model has proven to be a useful theoretical tool relating reductions in physiological variability found to accompany anxiety and concomitant reductions in behavioral (e.g., cognitive and emotional) flexibility. The present study aimed to extend the autonomic flexibility model through the inclusion of individual differences in the sensitivity of the independent motivational systems presumed to underlie anxiety and impulsivity, namely the behavioral inhibition and activation systems (BIS/BAS; Gray, 1994). Contrary to the predicted inverse relationship between BIS sensitivity and measures of physiological variability, findings suggest BAS sensitivity is associated with increased trait-like vagally mediated heart rate variability across diverse tasks as well as greater flexibility in responding within tasks. Numerous BIS*BAS interactions emerged as significant predictors of trait reactivity. Results are discussed in terms of the interface between (1) mesolimbic dopaminergic projections to the nucleus accumbens and (2) the network of central nervous system structures believed to play a large role in controlling peripheral physiology. / Ph. D.
422

Trustworthy Embedded Computing for Cyber-Physical Control

Lerner, Lee Wilmoth 20 February 2015 (has links)
A cyber-physical controller (CPC) uses computing to control a physical process. Example CPCs can be found in self-driving automobiles, unmanned aerial vehicles, and other autonomous systems. They are also used in large-scale industrial control systems (ICSs) manufacturing and utility infrastructure. CPC operations rely on embedded systems having real-time, high-assurance interactions with physical processes. However, recent attacks like Stuxnet have demonstrated that CPC malware is not restricted to networks and general-purpose computers, rather embedded components are targeted as well. General-purpose computing and network approaches to security are failing to protect embedded controllers, which can have the direct effect of process disturbance or destruction. Moreover, as embedded systems increasingly grow in capability and find application in CPCs, embedded leaf node security is gaining priority. This work develops a root-of-trust design architecture, which provides process resilience to cyber attacks on, or from, embedded controllers: the Trustworthy Autonomic Interface Guardian Architecture (TAIGA). We define five trust requirements for building a fine-grained trusted computing component. TAIGA satisfies all requirements and addresses all classes of CPC attacks using an approach distinguished by adding resilience to the embedded controller, rather than seeking to prevent attacks from ever reaching the controller. TAIGA provides an on-chip, digital, security version of classic mechanical interlocks. This last line of defense monitors all of the communications of a controller using configurable or external hardware that is inaccessible to the controller processor. The interface controller is synthesized from C code, formally analyzed, and permits run-time checked, authenticated updates to certain system parameters but not code. TAIGA overrides any controller actions that are inconsistent with system specifications, including prediction and preemption of latent malwares attempts to disrupt system stability and safety. This material is based upon work supported by the National Science Foundation under Grant Number CNS-1222656. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the authors and do not necessarily reflect the views of the National Science Foundation. We are grateful for donations from Xilinx, Inc. and support from the Georgia Tech Research Institute. / Ph. D.
423

Component-Based Design and Service-Oriented Architectures in Software-Defined Radio

Hilburn, Benjamin Cantrell 17 May 2011 (has links)
Software-Defined Radio (SDR) is a large field of research, and is rapidly expanding in terms of capabilities and applications. As the number of SDR platforms, deployments, and use-cases grow, interoperability, compatibility, and software re-use becomes more difficult. Additionally, advanced SDR applications require more advanced hardware and software platforms to support them, necessitating intelligent management of resources and functionality. Realizing these goals can be done using the paradigms of Component-Based Design (CBD) and Service-Oriented Architectures (SOAs). Component-based design has been applied to the field of SDR in the past to varying levels of success. We discuss the benefits of CBD, and how to successfully use CBD for SDR. We assert that by strictly enforcing the principles of CBD, we can achieve a high level of independence from both the hardware and software platforms, and enable component compatibility and interoperability between SDR platforms and deployments. Using CBD, we also achieve the use-case of a fully distributed SDR, where multiple hardware nodes act as one cohesive radio unit. Applying the concept of service-orientation to SDR is a novel idea, and we discuss how this enables a new radio paradigm in the form of goal-oriented autonomic radios. We define SOAs in the context of SDR, explain how our vision is different than middle-wares like CORBA, describe how SOAs can be used, and discuss the possibilities of autonomic radio systems. This thesis also presents our work on the Cognitive Radio Open Source Systems (CROSS) project. CROSS is a free and open-source prototype architecture that uses CBD to achieve platform independence and distributed SDR deployments. CROSS also provides an experimental system for using SOAs in SDRs. Using our reference implementation of CROSS, we successfully demonstrated a distributed cognitive radio performing dynamic spectrum access to communicate with another SDR while avoiding an interferer operating in the spectrum. / Master of Science
424

Altered Autonomic Nervous System Function in Chickens Divergently Selected for Body Weight

Kuo, Alice Yi-Wen 01 September 2000 (has links)
Autonomic nervous system activity is related to body weight regulation. Based on the MONA LISA hypothesis it has been suggested that most obese subjects and animals have low sympathetic nervous system activity. The aim of this study was to investigate whether there are differences in autonomic nervous system activity between lines of chickens selected for either high (HWS) or low body weight (LWS). In Exp. 1, various pharmacological agents were injected intravenously, and the changes in blood pressure (BP) and heart rate (HR) of both HWS and LWS chickens were compared. The results showed that the HWS birds had a greater increase in BP and HR than the LWS following injection of atropine, a muscarinic receptor blocker, and LWS birds had a greater decrease in BP and HR to propranolol, a beta- adrenergic receptor blocker than the HWS birds. These results suggested that HWS chickens have higher parasympathetic tone, whereas LWS chickens have a higher sympathetic nervous system tone regulating the cardiovascular system. HWS and LWS chickens displayed a similar response in BP and HR following injection of the ganglion blocker tetraethylammonium chloride. These results suggest that there is no significant difference in the central autonomic nervous system in the cardiovascular regulation between HWS and LWS together. Since there does not appear to be any differences in the activity of the autonomic nervous system activity at the level of the central nervous system, these findings imply that the difference in response to atropine and propranolol could be caused by differences in adrenal activity. The ratio of heart rate and blood pressure after the injection of phenylephrine showed significant difference between these two lines of birds, but not when phenylephrine was injected following atropine. This result indicated that HWS are more dependent on the parasympathetic nervous system to regulate the baroreceptor reflex. The percentage of adrenal and sympathetic impact on the regulation of heart rate showed that LWS females required greater adrenal activity than the other birds. In Exp. 2, the body weight and food intake responses of HWS and LWS chickens to ip injections of reserpine were compared. Reserpine caused a transitory decrease in food intake and body weight in both lines of birds. However HWS chickens recovered more slowly from the depression caused by reserpine than the LWS chickens. This could be due to lower sympathetic nervous system activity. In conclusion, it appears that HWS may have lower sympathetic activity than LWS. Combining the results of both experiments, it appears that the HWS birds have lower sympathetic and higher parasympathetic activity. Furthermore central nervous system autonomic activity in BP and HR regulation is not different between HWS and LWS, but the activity of the adrenal gland may be different between these two lines of birds. / Master of Science
425

Autonomic management in a distributed storage system

Tauber, Markus January 2010 (has links)
This thesis investigates the application of autonomic management to a distributed storage system. Effects on performance and resource consumption were measured in experiments, which were carried out in a local area test-bed. The experiments were conducted with components of one specific distributed storage system, but seek to be applicable to a wide range of such systems, in particular those exposed to varying conditions. The perceived characteristics of distributed storage systems depend on their configuration parameters and on various dynamic conditions. For a given set of conditions, one specific configuration may be better than another with respect to measures such as resource consumption and performance. Here, configuration parameter values were set dynamically and the results compared with a static configuration. It was hypothesised that under non-changing conditions this would allow the system to converge on a configuration that was more suitable than any that could be set a priori. Furthermore, the system could react to a change in conditions by adopting a more appropriate configuration. Autonomic management was applied to the peer-to-peer (P2P) and data retrieval components of ASA, a distributed storage system. The effects were measured experimentally for various workload and churn patterns. The management policies and mechanisms were implemented using a generic autonomic management framework developed during this work. The motivation for both groups of experiments was to test management policies with the objective to avoid unsatisfactory situations with respect to resource consumption and performance. Such unsatisfactory situations occur when either the P2P layer or the data retrieval mechanism is configured statically. In a statically configured P2P system two unsatisfactory situations can be identified. The first arises when the frequency with which P2P node states are verified is low and membership churn is high. The P2P node state becomes inaccurate due to a high membership churn, leading to errors during the routing process and a reduction in performance. In this situation it is desirable to increase the frequency to increase P2P state accuracy. The converse situation arises when the frequency is high and churn is low. In this situation network resources are used unnecessarily, which may also reduce performance, making it desirable to decrease the frequency. In ASA’s data retrieval mechanism similar unsatisfactory situations can be identified with respect to the degree of concurrency (DOC). The DOC controls the eagerness with which multiple redundant replicas are retrieved. An unsatisfactory situation arises when the DOC is low and there is a large variation in the times taken to retrieve replicas. In this situation it is desirable to increase the DOC, because by retrieving more replicas in parallel a result can be returned to the user sooner. The converse situation arises when the DOC is high, there is little variation in retrieval time and there is a network bottleneck close to the requesting client. In this situation it is desirable to decrease the DOC, since the low variation removes any benefit in parallel retrieval, and the bottleneck means that decreasing parallelism reduces both bandwidth consumption and elapsed time for the user. The experimental evaluations of autonomic management show promising results, and suggest several future research topics. These include optimisations of the managed mechanisms, alternative management policies, different evaluation methods, and the application of developed management mechanisms to other facets of a distributed storage system. The findings of this thesis could be exploited in building other distributed storage systems that focus on harnessing storage on user workstations, since these are particularly likely to be exposed to varying, unpredictable conditions.
426

Teste cardiopulmonar de exercício em pacientes com fibromialgia juvenil / Cardiopulmonary Exercise Test in patients with Juvenile fibromyalgia syndrome

Maia, Magda Maria 10 January 2017 (has links)
Introdução: A disfunção do sistema nervoso autônomo (disfunção autonômica ou dissautonomia) tem sido associada à fisiopatologia da fibromialgia em pacientes adultos. A modulação cardíaca em resposta ao exercício foi demonstrada em uma série de estudos em adultos com fibromialgia que evidenciaram reduzida capacidade aeróbia, assim como o comprometimento autonômico cardíaco e incompetência cronotrópica, que é a incapacidade de aumentar a frequência cardíaca concomitante ao aumento da intensidade do exercício. No entanto, a capacidade aeróbica e a disautonomia, definidas a partir da avaliação dos parâmetros do teste de exercício cardiopulmonar, não foram estudadas em pacientes adolescentes com síndrome da fibromialgia (FMJ). Objetivo: Avaliar os parâmetros do teste de exercício cardiopulmonar em pacientes com FMJ e controles saudáveis e as possíveis correlações entre estes parâmetros e a qualidade de vida relacionada à saúde (QVRS), capacidade funcional e dor nos pacientes FMJ. Métodos: Estudo transversal multicêntrico incluindo 25 pacientes com FMJ e 25 controles saudáveis. Ambos os grupos participavam somente das aulas de educação física na escola. O teste de exercício cardiopulmonar de esforço em esteira permitiu avaliar a resposta cardiorrespiratória durante o exercício. A resposta cronotrópica foi avaliada pela medida da reserva cronotrópica. Foram avaliados dor, capacidade funcional e QVRS. Resultados: A mediana da idade atual foi similar nos pacientes com FMJ e controles saudáveis (15 vs. 15 anos, p=0,890), assim como o índice de massa corporal (p=0,332), gênero feminino (p=1,000) e estágios de Tanner (p=0,822). A mediana dos parâmetros da QVRS (escore total de saúde física e saúde psicossocial) foi significativamente menor nos pacientes com FMJ versus controles, de acordo com o autorrelato dos pacientes e de seus pais (p < 0,001). A mediana do pico FC [181 (150-198) vs. 197 (181-202) bpm, p < 0,001], da reserva cronotrópica (RC) [84 (53-98) vs. 99 (84-103) %, p < 0,001] e da FC de repouso à FC de pico [96 (65-181) vs. 127 (61-185) bpm, p=0,010] foram significantemente menores nos pacientes com FMJ quando comparados aos controles saudáveis. A mediana do ?FCR1 [15 (3-39) vs. 35 (9-52) bpm, p < 0,001], deltaFCR2 [37 (20-57) vs. 51 (32-94) bpm, p < 0,001], VO2 de pico [32.34 (24.24-39.65) vs. 36.4 (28.56-52.71) ml/kg/min, p=0,005], velocidade máxima [5 (4-6.3) vs. 5.9 (4.0-6.3) mph, p=0,001], tempo de exaustão [11.5 (8.5-14.5) vs. 14 (11-18) minutos, p < 0,001] e capacidade de trabalho [3.37 (2.04-5.6) vs. 3.89 (2.91-6.55) W/kg, p=0,006] foram significativamente menores nos pacientes com FMJ quando comparados aos controles. A frequência da incompetência cronotrópica (<= 80%) foi significativamente maior nos pacientes com FMJ versus controles (p=0,0006). Conclusões: Este estudo identificou incompetência cronotrópica e recuperação atenuada da FC em pacientes com FMJ, indicando disfunção autonômica / Introdução: Autonomic nervous system dysfunction (also named autonomic disturbance or dysautonomia) has been linked to physiopathology of adult patients with fibromyalgia. Cardiac modulation in response to exercise in case series of adult fibromyalgia revealed reduced aerobic capacity, as well as cardiac autonomic impairment and chronotropic incompetence, which is the inability to increase heart rate with an increase in exercise intensity. However, to our knowledge treadmill cardiorespiratory test and to assess aerobic capacity and dysautonomia has not been studied in adolescents with JFM patients. Objective: To assess cardiorespiratory exercise test parameters in Juvenile fibromyalgia syndrome (JFM) patients and healthy controls and possible correlations between these parameters and health-related quality of life (HRQL), functional ability and pain in JFM patients. Methods: A multicenter cross-sectional study included 25 JFM patients and 25 healthy controls. Both groups were engaged only in the physical education classes in school. A treadmill graded cardiorespiratory test was performed and heart-rate (HR) response during exercise was evaluated by the chronotropic reserve (CR). Pain, functional ability and HRQL were assessed. Results: The median current age was similar in JFM and controls (15 vs. 15years, p=0.890), as well as body mass index (p=0.332), female gender (p=1.000) and Tanner stages (p=0.822). The medians of HRQL parameters (total score/physical health/psychosocial health) were significantly lower in JFM versus controls according to patient and parent self-reports (p<0.001). The median of peak HR [181 (150-198) vs. 197 (181-202) bpm, p < 0.001], chronotropic reserve [84 (53-98) vs. 99 (84-103)%, p < 0.001] and resting to peak [96 (65-181) vs. 127 (61-185) bpm, p=0.010] were significantly lower in JFM compared to controls. The median of ?HRR1 [15 (3-39) vs. 35 (9-52) bpm, p < 0.001], deltaHRR2 [37 (20-57) vs. 51 (32-94) bpm, p < 0.001], peak VO2 [32.34 (24.24-39.65) vs. 36.4 (28.56-52.71) ml/kg/min, p=0.005]; peak speed [5 (4-6.3) vs. 5.9 (4.0-6.3) km/h, p=0.001], time to exhaustion [11.5 (8.5-14.5) vs. 14 (11-18) minutes, p < 0.001] and working capacity on power [3.37 (2.04-5.6) vs. 3.89 (2.91-6.55) W/kg, p=0.006] were significantly lower in JFM compared to controls. The frequency of chronotropic incompetence ( <= 80%) was significantly higher in JFM versus controls (p=0.0006). Conclusions: This study identified chronotropic incompetence and delayed HR recovery in JFM patients, indicating autonomic dysfunction
427

Teste cardiopulmonar de exercício em pacientes com fibromialgia juvenil / Cardiopulmonary Exercise Test in patients with Juvenile fibromyalgia syndrome

Magda Maria Maia 10 January 2017 (has links)
Introdução: A disfunção do sistema nervoso autônomo (disfunção autonômica ou dissautonomia) tem sido associada à fisiopatologia da fibromialgia em pacientes adultos. A modulação cardíaca em resposta ao exercício foi demonstrada em uma série de estudos em adultos com fibromialgia que evidenciaram reduzida capacidade aeróbia, assim como o comprometimento autonômico cardíaco e incompetência cronotrópica, que é a incapacidade de aumentar a frequência cardíaca concomitante ao aumento da intensidade do exercício. No entanto, a capacidade aeróbica e a disautonomia, definidas a partir da avaliação dos parâmetros do teste de exercício cardiopulmonar, não foram estudadas em pacientes adolescentes com síndrome da fibromialgia (FMJ). Objetivo: Avaliar os parâmetros do teste de exercício cardiopulmonar em pacientes com FMJ e controles saudáveis e as possíveis correlações entre estes parâmetros e a qualidade de vida relacionada à saúde (QVRS), capacidade funcional e dor nos pacientes FMJ. Métodos: Estudo transversal multicêntrico incluindo 25 pacientes com FMJ e 25 controles saudáveis. Ambos os grupos participavam somente das aulas de educação física na escola. O teste de exercício cardiopulmonar de esforço em esteira permitiu avaliar a resposta cardiorrespiratória durante o exercício. A resposta cronotrópica foi avaliada pela medida da reserva cronotrópica. Foram avaliados dor, capacidade funcional e QVRS. Resultados: A mediana da idade atual foi similar nos pacientes com FMJ e controles saudáveis (15 vs. 15 anos, p=0,890), assim como o índice de massa corporal (p=0,332), gênero feminino (p=1,000) e estágios de Tanner (p=0,822). A mediana dos parâmetros da QVRS (escore total de saúde física e saúde psicossocial) foi significativamente menor nos pacientes com FMJ versus controles, de acordo com o autorrelato dos pacientes e de seus pais (p < 0,001). A mediana do pico FC [181 (150-198) vs. 197 (181-202) bpm, p < 0,001], da reserva cronotrópica (RC) [84 (53-98) vs. 99 (84-103) %, p < 0,001] e da FC de repouso à FC de pico [96 (65-181) vs. 127 (61-185) bpm, p=0,010] foram significantemente menores nos pacientes com FMJ quando comparados aos controles saudáveis. A mediana do ?FCR1 [15 (3-39) vs. 35 (9-52) bpm, p < 0,001], deltaFCR2 [37 (20-57) vs. 51 (32-94) bpm, p < 0,001], VO2 de pico [32.34 (24.24-39.65) vs. 36.4 (28.56-52.71) ml/kg/min, p=0,005], velocidade máxima [5 (4-6.3) vs. 5.9 (4.0-6.3) mph, p=0,001], tempo de exaustão [11.5 (8.5-14.5) vs. 14 (11-18) minutos, p < 0,001] e capacidade de trabalho [3.37 (2.04-5.6) vs. 3.89 (2.91-6.55) W/kg, p=0,006] foram significativamente menores nos pacientes com FMJ quando comparados aos controles. A frequência da incompetência cronotrópica (<= 80%) foi significativamente maior nos pacientes com FMJ versus controles (p=0,0006). Conclusões: Este estudo identificou incompetência cronotrópica e recuperação atenuada da FC em pacientes com FMJ, indicando disfunção autonômica / Introdução: Autonomic nervous system dysfunction (also named autonomic disturbance or dysautonomia) has been linked to physiopathology of adult patients with fibromyalgia. Cardiac modulation in response to exercise in case series of adult fibromyalgia revealed reduced aerobic capacity, as well as cardiac autonomic impairment and chronotropic incompetence, which is the inability to increase heart rate with an increase in exercise intensity. However, to our knowledge treadmill cardiorespiratory test and to assess aerobic capacity and dysautonomia has not been studied in adolescents with JFM patients. Objective: To assess cardiorespiratory exercise test parameters in Juvenile fibromyalgia syndrome (JFM) patients and healthy controls and possible correlations between these parameters and health-related quality of life (HRQL), functional ability and pain in JFM patients. Methods: A multicenter cross-sectional study included 25 JFM patients and 25 healthy controls. Both groups were engaged only in the physical education classes in school. A treadmill graded cardiorespiratory test was performed and heart-rate (HR) response during exercise was evaluated by the chronotropic reserve (CR). Pain, functional ability and HRQL were assessed. Results: The median current age was similar in JFM and controls (15 vs. 15years, p=0.890), as well as body mass index (p=0.332), female gender (p=1.000) and Tanner stages (p=0.822). The medians of HRQL parameters (total score/physical health/psychosocial health) were significantly lower in JFM versus controls according to patient and parent self-reports (p<0.001). The median of peak HR [181 (150-198) vs. 197 (181-202) bpm, p < 0.001], chronotropic reserve [84 (53-98) vs. 99 (84-103)%, p < 0.001] and resting to peak [96 (65-181) vs. 127 (61-185) bpm, p=0.010] were significantly lower in JFM compared to controls. The median of ?HRR1 [15 (3-39) vs. 35 (9-52) bpm, p < 0.001], deltaHRR2 [37 (20-57) vs. 51 (32-94) bpm, p < 0.001], peak VO2 [32.34 (24.24-39.65) vs. 36.4 (28.56-52.71) ml/kg/min, p=0.005]; peak speed [5 (4-6.3) vs. 5.9 (4.0-6.3) km/h, p=0.001], time to exhaustion [11.5 (8.5-14.5) vs. 14 (11-18) minutes, p < 0.001] and working capacity on power [3.37 (2.04-5.6) vs. 3.89 (2.91-6.55) W/kg, p=0.006] were significantly lower in JFM compared to controls. The frequency of chronotropic incompetence ( <= 80%) was significantly higher in JFM versus controls (p=0.0006). Conclusions: This study identified chronotropic incompetence and delayed HR recovery in JFM patients, indicating autonomic dysfunction
428

Effect of short-term heart rate variability biofeedback on long-term abstinence in alcohol dependent patients – a one-year follow-up

Penzlin, Ana Isabel, Barlinn, Kristian, Illigens, Ben Min-Woo, Weidner, Kerstin, Siepmann, Martin, Siepmann, Timo 18 December 2017 (has links) (PDF)
Background: A randomized controlled study (RCT) recently showed that short-term heart rate variability (HRV) biofeedback in addition to standard rehabilitation care for alcohol dependence can reduce craving, anxiety and improve cardiovascular autonomic function. In this one-year follow-up study we aimed to explore whether completion of 2-week HRV-Biofeedback training is associated with long-term abstinence. Furthermore, we sought to identify potential predictors of post-treatment abstinence. Methods: We conducted a survey on abstinence in patients with alcohol dependence 1 year after completion of an RCT comparing HRV-biofeedback in addition to inpatient rehabilitation treatment alone (controls). Abstinence rates were compared and analysed for association with demographic data as well as psychometric and autonomic cardiac assessment before and after completion of the biofeedback training using bivariate and multivariate regression analyses. Results: Out of 48 patients who participated in the RCT, 27 patients (9 females, ages 42.9 ± 8.6, mean ± SD) completed our one-year follow-up. When including in the analysis only patients who completed follow-up, the rate of abstinence tended to be higher in patients who underwent HRV-biofeedback 1 year earlier compared to those who received rehabilitative treatment alone (66.7% vs 50%, p = ns). This non-significant trend was also observed in the intention-to-treat analysis where patients who did not participate in the follow-up were assumed to have relapsed (46,7% biofeedback vs. 33.3% controls, p = ns). Neither cardiac autonomic function nor psychometric variables were associated with abstinence 1 year after HRV-biofeedback. Conclusion: Our follow-up study provide a first indication of possible increase in long-term abstinence after HRVbiofeedback for alcohol dependence in addition to rehabilitation. Trial registration: The original randomized controlled trial was registered in the German Clinical Trials Register (DRKS00004618). This one-year follow-up survey has not been registered.
429

Effect of short-term heart rate variability biofeedback on long-term abstinence in alcohol dependent patients – a one-year follow-up

Penzlin, Ana Isabel, Barlinn, Kristian, Illigens, Ben Min-Woo, Weidner, Kerstin, Siepmann, Martin, Siepmann, Timo 18 December 2017 (has links)
Background: A randomized controlled study (RCT) recently showed that short-term heart rate variability (HRV) biofeedback in addition to standard rehabilitation care for alcohol dependence can reduce craving, anxiety and improve cardiovascular autonomic function. In this one-year follow-up study we aimed to explore whether completion of 2-week HRV-Biofeedback training is associated with long-term abstinence. Furthermore, we sought to identify potential predictors of post-treatment abstinence. Methods: We conducted a survey on abstinence in patients with alcohol dependence 1 year after completion of an RCT comparing HRV-biofeedback in addition to inpatient rehabilitation treatment alone (controls). Abstinence rates were compared and analysed for association with demographic data as well as psychometric and autonomic cardiac assessment before and after completion of the biofeedback training using bivariate and multivariate regression analyses. Results: Out of 48 patients who participated in the RCT, 27 patients (9 females, ages 42.9 ± 8.6, mean ± SD) completed our one-year follow-up. When including in the analysis only patients who completed follow-up, the rate of abstinence tended to be higher in patients who underwent HRV-biofeedback 1 year earlier compared to those who received rehabilitative treatment alone (66.7% vs 50%, p = ns). This non-significant trend was also observed in the intention-to-treat analysis where patients who did not participate in the follow-up were assumed to have relapsed (46,7% biofeedback vs. 33.3% controls, p = ns). Neither cardiac autonomic function nor psychometric variables were associated with abstinence 1 year after HRV-biofeedback. Conclusion: Our follow-up study provide a first indication of possible increase in long-term abstinence after HRVbiofeedback for alcohol dependence in addition to rehabilitation. Trial registration: The original randomized controlled trial was registered in the German Clinical Trials Register (DRKS00004618). This one-year follow-up survey has not been registered.
430

Internet des Objets centré service autocontrôlé / Self-controlled service-centric Internet of Things

Lemoine, Frédéric 03 July 2019 (has links)
A l'heure du numérique, la quantité d'objets connectés ne cesse de croître et de se diversifier. Afin de supporter cette complexité croissante, nous avons souhaité apporter un maximum d'automatismes à l'Internet des Objets de manière à garantir une qualité de service (QoS) de bout en bout. Pour ce faire, un composant de service autocontrôlé est proposé pour intégrer l'objet dans l'écosystème digital. Grâce à la calibration de chaque service, qui permet la connaissance du comportement, une composition automatisée devient possible. Nous avons illustré la faisabilité de notre approche à travers un cas d'étude. Nous avons également montré comment les objets connectés peuvent s'assembler eux-mêmes, coopérant pour atteindre un objectif commun, tout en répondant aux exigences de QoS globales. / In the digital era, the number of connected objects continues to grow and diversify. To support this increasing complexity, we wanted to bring a maximum of automatisms to the Internet of Things in order to guarantee end-to-end quality of service (QoS). To do this, a self-controlled service component is proposed to integrate the object into the digital ecosystem. Thanks to the calibration of each service, which makes it possible to know the behaviour, an automated composition becomes possible. We have illustrated the feasibility of our approach on a case study. We also have shown how connected objects can assemble themselves, cooperating to achieve a common objective, while meeting global QoS requirements.

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