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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.
71

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.
72

Socialarbetares föreställningarav- och arbete medhedersvåldsutsatta kvinnor

Hoffsten, Sara, Mahfoud, Sarah January 2024 (has links)
Hedersrelaterat våld och förtryck (HRV) är ett komplext fenomen somnyligen fått utökat utrymme inom svensk debatt och politik. Tidigareforskning visar att det saknas förståelse för hedersrelaterat våld utanförramarna av kulturella perspektiv. Vidare leder detta till en otillräcklig ochsimplifierad bild av fenomenet. Forskning visar även att behandlare somhjälper och vårdar hedersvåldsutsatta kvinnor bemöter klienten utifrån sinaföreställningar. Föreställningar om individer av annan kultur är oftageneraliserande och påverkar kvalitén på given hjälp och vård. Syftet meddenna studie är att undersöka hur socialarbetare beskriver sitt arbete medhedersvåldsutsatta kvinnor. Vi ämnar även att undersöka vilka föreställningarom kvinnorna som framkommer ur socialarbetarnas beskrivning av arbetet.Genom semistrukturerade kvalitativa intervjuer med socialarbetare inomfältet av HRV framkom att det idag finns fler hinder än möjligheter i detpraktiska arbetet. Resultatet av denna studie visar att den hedersvåldsutsattakvinnan generaliseras då hon sällan blir förstådd utanför kontexten av henneskultur. Därigenom blir våldet hon utsätts för förminskat med tiden. Dettabeskrivs främst ha grund i att det hjälpande och stöttande arbetet utförs undertids- och resursbrist. Därför är det av vikt att den hjälpsökandehedersvåldsutsatta kvinnan får professionella möten där vikt läggs påinkludering och individuella behov. Resultatet visar att kvinnan som kännersig förstådd stannar kvar i det professionella samarbetet och har större chansatt bryta sig från våldet inom hennes familj.
73

Contribuição das eletrocardiografias convencional, holter e de alta resolução no diagnóstico da cardiomiopatia arritmogênica do ventrículo direito dos cães da raça boxer /

Pereira, Evandro Zacché. January 2011 (has links)
Orientador: Aparecido Antonio Camacho / Banca: Wagner Luís Ferreira / Banca: Mirela Tinucci Costa / Resumo: Com o objetivo de investigar a importância de ferramentas que possam identificar as arritmias ou detectar seus possíveis fatores desencadeantes em portadores da cardiomiopatia arritmogênica do ventrículo direito, 25 cães Boxers foram submetidos ao exame eletrocardiográfico convencional (ECG) e variabilidade da frequência cardíaca (VFC), obtida pela avaliação Holter de 24 horas, e 20 foram submetidos ao exame eletrocardiográfico de alta resolução (ECGAR). Os cães foram divididos em três grupos de acordo com o número de extrassístoles ventriculares (EV) obtidas pela avaliação Holter. O GC foi composto por cães apresentando menos de 20 EV/24 horas, o GD1 foi formado por animais com mais de 100 e menos de 1.000 EV/24 horas, enquanto o GD2 foi composto por animais que apresentaram mais de 1.000 EV/24 horas. Levando em consideração a presença de EV e extrassístoles supraventriculares (ESV) no ECG, este teste apresentou 83,33% de sensibilidade, 100% de especificidade, valor preditivo positivo (VPP) de 100% e valor preditivo negativo (VPN) de 86%. Os parâmetros da VFC SDNNIDX (Gc: 194,08 ± 56,29 ms; GD1: 202,20 ± 94,79 ms; GD2: 118,00 ± 43,76 ms) e pNN>50 (Gc: 39,75 ± 12,69 ms; GD1: 46,24 ± 14,08; GD2: 21,52 ± 9,27 ms) foram significativamente menores nos pacientes do GD2. O ECGAR apresentou sensibilidade de 30%, especificidade de 50%, VPP de 37,5% e VPN de 41,67%. Assim, os resultados sugerem que a eletrocardiografia convencional e a VFC são técnicas que podem contribuir substancialmente no diagnóstico da CAVD em cães Boxers, ao contrário da eletrocardiografia de alta resolução que se mostrou ineficaz em identificar a presença de potenciais tardios nos pacientes com esse grau de doença / Abstract: Aiming to investigate the importance of tools that could identify arrhythmias or detect its possible inciting factor in patients affected by arrhythmogenic right ventricular cardiomyopathy, 25 Boxer dogs were submitted to conventional electrocardiogram (ECG), heart rate variability (HRV), obtained by 24-hours Holter evaluation, and 20 were submitted to high resolution electrocardiogram (HRECG). Dogs were divided into three different groups according to the number of ventricular complexes (VC) obtained in Holter analysis. The GC was formed by dogs presenting less than 20 VC/24 hours, the GD1 was formed by animals presenting more than 100 and less than 1.000 VC/24 hours, while the GD2 was composed of dogs presenting over a 1.000 VC/24 hours. Considering the presence of ventricular or supraventricular complexes on the ECG, this test had 83,33% of sensitivity, 100% of specificity, positive predictive value (PPV) of 100% and negative predictive value (NPV) of 86%. The HRV parameters SDNNIDX (Gc: 194.08 ± 56.29 ms; GD1: 202.20 ± 94.79 ms; GD2: 118.00 ± 43.76 ms) and pNN>50 (Gc: 39.75 ± 12.69 ms; GD1: 46.24 ± 14.08; GD2: 21.52 ± 9.27 ms) were significantly lower in the patients of GD2. The HRECG showed 30% of sensitivity, 50% of specificity, PPV of 37,5% and NPV of 41,67%. Thus, the results suggest that conventional ECG and HRV are techniques that can strongly contribute in the diagnosis of ARVD in Boxer dogs, opposed to HRECG that showed itself inefficient to detect the presence of late potentials in patients with this degree of disease / Mestre
74

Modélisation de l'érosion hydrique par intégration de données multisources à un système d'information géographique

Baril, Daniel January 1989 (has links)
Résumé : La dégradation des sols est un processus qui affecte les terres agricoles de la majorité des pays du monde. L'érosion hydrique est d'ailleurs le phénomène de dégradation des sols le plus apparent mais aussi le plus sous-estimé par les agriculteurs. L'objectif de cette recherche est donc d'intégrer à un système d'information géographique (S.I.G.) les facteurs de l'équation universelle des pertes de sol (U.S.L.E.) afin de modéliser les pertes de sol dues à l'érosion hydrique. Cette méthodologie a été appliquée sur un secteur agricole d'environ 500 km2 situé dans les Cantons de l'Est (sud du Québec). Une image satellite HRV de SPOT nous a permis de cartographier l'utilisation du sol. Du modèle numérique d'élévation (M.N.É.) nous avons dérivé la pente et de la longueur de pente nécessaires au calcul du facteur de topographie. Finalement, à la carte pédologique numérisée, nous associons les indices d'érodabilité de chacun des types de sol mesurés à l'aide d'un simulateur de pluie. L'utilisation d'outils modernes et flexibles tels la télédétection et les systèmes d'information géographique (S.I.G.) nous a permis d'améliorer la rapidité de calcul des pertes de sol afin de couvrir de plus vastes territoires. Nous pourrons ainsi contribuer à déterminer plus rapidement et adéquatement des moyens pour corriger la situation avant que les sols les plus sensibles ne deviennent infertiles. Pour l'ensemble du territoire à l'étude, nous avons obtenu des pertes totales de sol de 791 tonnes métriques/an. Elles sont réparties comme suit: 24 Van pour la forêt, 95 Van pour les cultures et 672 t/an pour les secteurs de sol nu. De plus, on observe que 84,96% des pertes de sols se retrouvent sur les sols nus qui ne représentent que 7,35% du territoire. Les forêts qui couvrent 66,09% du territoire n'obtiennent que 3,03 % des pertes totales de sol.||Abstract : Soil degradation is a process that affects croplands in all countries around the word. Water erosion is the most frequently observed process involved in soil degradation but also the less well known by farmers. The purpose of this study is to integrate into a geographical information system (G.I.S.) the universal soil loss equation (U.S.L.E.) factors to estimate soil losses due to water erosion. This methodology was applied in an agricultural region of 500 km2 in the Eastern Townships (southern Quebec). A HRV SPOT satellite image was used to determine land use. From the digital elevation model (D.E.M.) we derived the slope and slope length required to calculate the topographic factor (LS factor). Finally, we added to the G.I.S. the digitized soil map units with their soil erodibility based on rainfall simulator measurements. The use of modern and flexible tools like remote sensing and geographical information systems (G.I.S.) allowed us to increase calculation speed of soil loss to cover more territoriy. This method will also contribute to determine more quickly and adequately the solutions to correct the situation before the more sensitive soils become unfertile. For all our study area, we obtained a total soil loss of 791 metric tons/year. These are divided as follows: 24 t/an for forest, 95 t/an for crops and 672 t/an for bare soils. We also observe that 84,96% of soil losses were found on bare soils that represent only 7,35% of the territory. Forests that cover 66,09% of the territory represent only 3,03 % of the total soil losses.
75

Heart Rate Variability Extraction from Video Signals

Alghoul, Karim January 2015 (has links)
Heart Rate Variability (HRV) analysis has been garnering attention from researchers due to its wide range of applications. Medical researchers have always been interested in Heart Rate (HR) and HRV analysis, but nowadays, investigators from variety of other fields are also probing the subject. For instance, variation in HR and HRV is connected to emotional arousal. Therefore, knowledge from the fields of affective computing and psychology, can be employed to devise machines that understand the emotional states of humans. Recent advancements in non-contact HR and HRV measurement techniques will likely further boost interest in emotional estimation through . Such measurement methods involve the extraction of the photoplethysmography (PPG) signal from the human's face through a camera. The latest approaches apply Independent Component Analysis (ICA) on the color channels of video recordings to extract a PPG signal. Other investigated methods rely on Eulerian Video Magnification (EVM) to detect subtle changes in skin color associated with PPG. The effectiveness of the EVM in HR estimation has well been established. However, to the best of our knowledge, EVM has not been successfully employed to extract HRV feature from a video of a human face. In contrast, ICA based methods have been successfully used for HRV analysis. As we demonstrate in this thesis, these two approaches for HRV feature extraction are highly sensitive to noise. Hence, when we evaluated them in indoor settings, we obtained mean absolute error in the range of 0.012 and 28.4. Therefore, in this thesis, we present two approaches to minimize the error rate when estimating physiological measurements from recorded facial videos using a standard camera. In our first approach which is based on the EVM method, we succeeded in extracting HRV measurements but we could not get rid of high frequency noise, which resulted in a high error percentage for the result of the High frequency (HF) component. Our second proposed approach solved this issue by applying ICA on the red, green and blue (RGB) colors channels and we were able to achieve lower error rates and less noisy signal as compared to previous related works. This was done by using a Buterworth filter with the subject's specific HR range as its Cut-Off. The methods were tested with 12 subjects from the DISCOVER lab at the University of Ottawa, using artificial lights as the only source of illumination. This made it a challenge for us because artificial light produces HF signals which can interfere with the PPG signal. The final results show that our proposed ICA based method has a mean absolute error (MAE) of 0.006, 0.005, 0.34, 0.57 and 0.419 for the mean HR, mean RR, LF, HF and LF/HF respectively. This approach also shows that these physiological parameters are highly correlated with the results taken from the electrocardiography (ECG).
76

"Vi måste våga fråga" : en kvalitativ intervjustudie om skolsköterskors möte med barn som utsätts för hedersrelaterat våld och förtryck

Lindqvist, Ammie, Westermark, Sara January 2020 (has links)
Hedersrelaterat våld och förtryck (HRV) drabbar barn som lever i en hederskultur. Idag lever minst 5 % av Sveriges skolbarn under HRV. Skolsköterskor har en central roll i att identifiera barn som är utsatta. I rollen ligger ett ansvar att lindra lidande, och att arbeta hälsofrämjande och förebyggande. Enligt vår kännedom finns inga tidigare studier i ämnet men angränsande studier ger kunskap om skolsköterskors viktiga roll. HRV leder till att barn blir begränsade i sina rättigheter och friheter. Studiens syfte är att belysa skolsköterskors erfarenheter av att möta barn som utsätts för HRV. Data samlades in via semistrukturerade intervjuer med tio skolsköterskor och analyserades med kvalitativ innehållsanalys enligt Graneheim och Lundman. Resultatet belyser skolsköterskans erfarenhet av att möta barn som utsätts för HRV i tre kategorier, relationens betydelse med det utsatta barnet, samverkans betydelse för skolsköterskorna kring det utsatta barnet och erfarenheten och kunskapens betydelse för skolsköterskornas agerande. Varje kategori inkluderar två till fyra underkategorier. I resultatet framkommer vikten av att tidigt identifiera barn som utsätts, att se tecken och att skapa en förtroendefull relation där det vårdande samtalet får ta plats. Även vikten av samverkan synliggörs. Det framkommer att brister i arbetet leder till osäkerhet hos skolsköterskorna. Slutsatsen är att skolsköterskors osäkerhet leder till att barn inte alltid får det stöd och hjälp som de behöver. Att möta komplexiteten vid HRV kräver mod, adekvat kunskap och kompetens. HRV behöver motverkas på samhällets alla nivåer.
77

Analýza sympato-vagální rovnováhy / Sympatovagal balance analysis

Rusz, Jakub January 2018 (has links)
The main focus of this work is to describe and implement a method to analyze sympathovagal balance. The theoretical part begins with electrocardiogram origin and measurement followed by heart rate variability explanation and a method of tachogram creation. The chapter is finished by description of wavelet transform as a means for tachogram processing and obtaining the sympato-vagal balance coeficient. Practical part of work focuses on developing a solution in Matlab for this problem. The R detector, tachogram creation and wavelet transform processing scripts with sympato-vagal balance assesment are fully described along with an example of their outputs. The work is finished with a conclusion of the findings and the assessment of sympato-vagal balance form them, which is unfortunately not so simple.
78

Klasifikace EKG na základě metod HRV analýzy / ECG classification using methods of HRV analysis

Caha, Martin January 2013 (has links)
This paper deals with the classification of ECG measured from isolated rabbit hearts during the experiment with repeated ischemia. Classification features were calculated using the methods of heart rate variability analysis. The results were statistically evaluated. Heart rate variability parameters were calculated using Kubios HRV, other calculations were performed in MATLAB. Artificial neural network was created to classify the analyzed parameters to specific groups.
79

Developmental Patterns of EEG and ECG Physiological Similarity Between Mother and Child

Bertrand, Christina 18 March 2022 (has links)
Physiological indicators like heart rate (HR) and its variability (HRV) from ECG (electrocardiograms), and frontal lobe alpha power asymmetry (AA) and frontoparietal connectivity from EEG (electroencephalograms), can elucidate the role of the nervous system and other visceral organs and their effects on behavioral measures of cognitive and emotional self-regulation. Knowledge of the intergenerational transmission of cardiac and cerebral physiology can provide insight as to the developmental patterns of the organization and stabilization of these physiological processes in children and their mothers. The current study addresses a key question: Is there a developmental shift from 3-9 years of age in the overall pattern of EEG and ECG similarity between children and their mothers? The hypothesis was that there would be increasing child-mother similarity with age. EEG and ECG physiology was examined during a resting-state baseline period, during completion of cognitive tasks, and as baseline-to-task changes in EEG AA and frontoparietal coherence, and ECG HR and HRV in children and their mothers. A socioeconomically diverse longitudinal sample of 171 mothers with their children at ages 3, 6, and 9 years completed questionnaires and laboratory visits. Results indicated that there was some evidence to suggest the presence of mother-child similarity. Twenty of the seventy-two estimated intraclass correlations were significant. Furthermore, of the 20 significant correlations overall, none were present at child age 3 years, 6 were significant at child age 6 years, and 14 were significant at child age 9 years. Thus, overall, there was evidence that by age 6 years, child-mother similarity in physiological indicators of SR had begun to emerge. Additionally, consistent with the study hypothesis, there was some evidence of a pattern of increasing similarity for certain physiological indicators. Of the 72 estimated age-difference Fisher tests for increasing similarity, 17 were significant and in the hypothesized direction. The greatest number were seen during the task condition for ages 6 and 9, and particularly for the frontoparietal EEG variables. Findings are interpreted in light of social learning and behavioral genetics theories.
80

Assessing the relationship between resting autonomic nervous system functioning, social anxiety, and emotional autobiographical memory retrieval

Smith, Brianna January 2018 (has links)
Thesis advisor: Elizabeth Kensinger / Individuals with social anxiety disorder (SAD) tend to have emotional memory biases in the encoding and retrieval of social memories. Research has shown reduced heart rate variability (HRV) in clinical populations suffering from anxiety, including social anxiety. Heightened sympathetic activation—as measured by the electrodermal activity (EDA)—has also been associated with anxiety disorders. The aim of the present study was to examine the relation between HRV, social anxiety, and re-experiencing of emotional autobiographical memories. 44 healthy young adults were recruited from the Boston College campus through SONA. Participants were given an online survey that instructed them to retrieve 40 specific events from the past in response to 40 socially relevant cues. For each event, participants were instructed to provide a brief narrative, make several ratings for the event (on a scale from 1-7), and indicate the specific emotions they experienced both at the time of retrieval and of the event. Approximately one month after the completion of the memory survey, participants engaged in a 2-hour memory retrieval session while undergoing psychophysiological monitoring (heart rate, skin conductance, and respiration). Following the retrieval task, participants completed self-report questionnaires of social anxiety symptom severity and trait emotion regulation strategy (i.e., tendency to reappraise or suppress emotions). The present study found that positive memories had higher re-experiencing ratings as compared to negative memories. Contrary to the original study hypothesis, however, there was no significant interaction between average re-experiencing (or arousal) ratings of positive or negative social autobiographical memories and SAD likelihood. A nonlinear, cubic relationship was found between one of three metrics of HRV and social anxiety symptom severity. A significant effect was found between skin conductance and SAD likelihood, which was likely driven by an almost significance difference in skin conductance between the SAD unlikely and the SAD very probable groups; these findings provide further insight into the relationship between autonomic nervous system (ANS) functioning and social anxiety. Further, the present results suggest the intriguing possibility that there may be a nonlinear relationship between HRV and severity of social anxiety. Future research with a larger sample size is needed to corroborate these findings. / Thesis (BS) — Boston College, 2018. / Submitted to: Boston College. College of Arts and Sciences. / Discipline: Departmental Honors. / Discipline: Psychology.

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