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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.
251

Parametrizace dyskomfortu organismu řidiče a spolujezdce při monotónní zátěži v průběhu jízdy osobním automobilem / Parameterization of body discomfort of driver and front passanger in a monotone load during driving by car

Kaucová, Jana January 2015 (has links)
Title: Parameterization of body discomfort of driver and front passanger in a monotone load during driving by car Objectives: The aim of this work based on the implemented case study is determination utilization of selected subjective and objective methods to assess discomfort sitting position of driver and front passanger in the monotone load during driving by car. Methods: This thesis is type of descriptive - association qualitative research. In practical part the objective discomfort parameters were monitored using Mobile system for scanning and evaluation of occupational safety and hygiene and the subjective parameters using Questionnaire physical map in combination with modified Borg scale, the mental state was monitored using modified questionnaire POMS. Results: Detailed link was not proved in context of subjective and objective methods or roles, the measurements were too influenced by entering factors and variability of observed objective parameters. The skin temperature, wetness and heart rate appear to be unsuitable for monitoring the sitting discomfort in realistic conditions, subjective methods are usable in research. Their results showed that the subjective discomfort and fatigue grew more during ride back. Pause resulted in reduced subjective discomfort. Keywords: skin temperature,...
252

Adaptace vojenských pilotů nadzvukových letadel na stresovou zátěž / Adaptation of military pilots of supersonic aircrafts on stress workload

Kloudová, Gabriela January 2015 (has links)
This diploma thesis deals with impact of stress on performance of military pilots of supersonic aircrafts. The theoretical part is based on definition of the term stress, his relating theories, the strategies of coping with stress and possible methods of objectivization of mental workload. This part also provides an overview of stress occuring during flight activity and specifics of the job of military pilot. The research is based on theoretical models and previous researches and the aim is to analyze the hypothesis about the dependence of stress on performance of the military pilot.This correlation was empirically verified by experimental study conducted in tactical flight simulator designed for a training on supersonic airplanes. The mental workload was investigated by physiological data and psychological questionnaires. The results are showing the most stressful and most difficult situations that appeared during tactical combat mission. There was a significant correlation between personality, resting heart rate and the effectivity of the performance. Key words: Stress, Military pilots, Performance, Mental workload, Heart rate
253

Porovnání hodnot SF a vnějšího výkonu u vybraných terénních testů pro stanovení SFmax v jízdě na kole u cyklistů a triatlonistů. / Comparison of heart rate and external performance at selected field tests for determining maximum heart rate for bicyclists and triathletes when cycling.

Podrazil, Tomáš January 2014 (has links)
Title: Comparison of the heart rate values and external performance is based on selected field tests determining maximal heart rate in cycling of cyclist and triathletes Objectives: Objective of thesis is to determine the values of maximal heart rate and external performance from selected field tests in cycling and compare them with one another. Methods: Five cyclist were measured in field tests and acquired results were used to create the graphs and tables. Data were obtained by cycling performance meter Powertap and cycle computer Garmin Edge 500. For the analysis of the measured data was used software Garmin Connect. Results: Based on the results of thesis it can be stated, that the measurement turn out as we expected. The difference of maximal heart rate between test-A and test-B is differed by 3-5 beats, which is not decisive. Both tests can be used for determine maximal heart rate. These tests are suitable for measuring the performance of athletes. Maximal heart rate is not in present an important indicator for training of fitness of individual. For training I would suggest to take a test of lactate curve in the laboratory. Keywords: cycling, external performance, heart rate, terrain test, Powertap
254

Reakce kardiovaskulárního systému u pacientů s míšní lézí na terpii v lokomatu / Reactions of cardiovascular system to locomat therapy in patients with lesion of the spinal cord

Stráníková, Kateřina January 2013 (has links)
Introduction - This thesis focuses on the reaction of cardiovascular system to Lokomat therapy in patients with lesion of the spinal cord. It observes reaction of the heart rate and systolic blood pressure and compares with the cardiovascular response to the exercise on an upper body ergometer. Methods - We recruited 25 patients with spinal cord lesion under Th 5 and 4 patients with lesion above Th 5. The blood pressure was measured. The heart rate was measured by by ambulatory blood pressure monitor and an auscultatory method using a mercury manometer and a stethoscope a sporttester. Patients were measured during the Locomat therapy and the exercise on an upper body ergometer during the 6-minute arm test. Results - The parameters of systolic blood pressure and heart rate had a tendency to increase with the peak in 25th minute of the therapy. There was no significant difference between the patients with lesion under or above Th5. The parameters of heart rate were significantly higher on the upper body ergometer than on Lokomat. Conclusion - The Lokomat therapy does have a positive influence to cardiovascular system of patients with complete or incomplete spinal cord injury. When using this approach, the most important benefit is the possibility to activate all parts of body. Keywords: spinal cord injury,...
255

Porovnání hodnot SF a vnějšího výkonu u vybraných terénních testů pro stanovení SFmax v jízdě na kole u cyklistů a triatlonistů. / Comparison of heart rate and external performance at selected field tests for determining maximum heart rate for bicyclists and triathletes when cycling.

Podrazil, Tomáš January 2014 (has links)
Title: Comparison of the heart rate values and external performance is based on selected field tests determining maximal heart rate in cycling of cyclist and triathletes Objectives: Objective of thesis is to determine the values of maximal heart rate and external performance from selected field tests in cycling and compare them with one another. Methods: Three cyclist were measured in field tests and acquired results were used to create the graphs and tables. Data were obtained by cycling performance meter Powertap and cycle computer Garmin Edge 500. For the analysis of the measured data was used software TrainigsPeaks.com Results: Based on the results of thesis it can be stated, that the measurement turn out as we expected. The difference of maximal heart rate between test-A and test-B is differed by 3-5 beats, which is not decisive. Both tests can be used for determine maximal heart rate. These tests are suitable for measuring the performance of athletes. Maximal heart rate is not in present an important indicator for training of fitness of individual. For training I would suggest to take a test of lactate curve in the laboratory. Keywords: cycling, external performance, heart rate, terrain test, Powertap
256

Analýza vnitřního zatížení u hráčů plážového volejbalu. / Analysis of internal load for beach beachvolleyball players

Čirka, Jan January 2016 (has links)
Title: Analysis of internal load for beach beachvolleyball players The aim of the work: The goal of this work is to determine the size of the musculoskeletal load of beachvolleyball players in several games of the Czech Cup. At the same time the objective of this work is to determine diffferences in size of the kinetic load between players on various positions and show in which levels and for how long time are players in each level during the match. Method: In this work is used indirect (mediated) observation. Data were recorded using the devices from which the information was subsequently processed in the result form. The assess the magnitude of musculoskeletal load were used sport testers "Polar Team 2." Results: The measurement results have shown, that beachvolleyball players were during the matches mostly in the aerobic - anaerobic zone. On average in selected matches harder working player was setter. Keywords: Beachvoleyball Fitness training Musculoskeletal load Heart rate
257

Verifikace vlivu instruktora na zatížení v průběhu lekce jumpingu / Verification of instructors influences upon loading during jumpig lesson

Novotná, Klára January 2013 (has links)
Title: Verification of instructor influence on the load during exercise session of "Jumping". Goals: The main goal is to observe the dynamics of heart rate during the 62-minute exercise session of "Jumping" and to observe the impact of the instructor on the cardiovascular system load, by monitoring heart rate. Methods: During the exercise session of "Jumping" we observe the cardiovascular system load on 38 volunteers aged 18-30 years, by monitoring of heart rate. For measuring heart rate, we used equipment Polar RS800CX. Probands were divided into four groups according to gender and age. Two groups of men and women in each age categories up to 20 years and from 21 to 30 years. Each proband completed four exercise sessions lasting about 62 minutes. The sessions were led by four different instructors. Results: The analysis results show that the average heart rates during 62 minute exercise session of "Jumping" are not significantly different. Measured values showed that Jumping is not aerobic activity. Keywords: Jumping, trampoline, heart rate, cardiovascular system, sport tester
258

Accidental hypothermia and local cold injury : physiological and epidemiological studies on risk

Brändström, Helge January 2012 (has links)
Background: (Papers I and II) The objectives were to first determine incidence and contributing factors to cold-related injuries in northern Sweden, both those that led to hospitalization and those that led to fatality.  (Papers III and IV) A further aim was to assess post-cooling hand-rewarming responses and effects of training in a cold environment, both on fingertip rewarming and on function of the autonomic nervous system, to evaluate if there was adaptation related to prolonged occupational cold exposure. Methods:  In a retrospective analysis, cases of accidental cold-related injury with hospital admission in northern Sweden during 2000-2007 were analyzed (Paper I).  Cases of fatal hypothermia in the same region during 1992-2008 were analyzed (Paper II).  A cohort of volunteers was studied before and after many months of occupational cold exposure. Subject hand rewarming response was measured after a cold hand immersion provocation and categorized as slow, moderate or normal in rewarming speed.  This cold provocation and rewarming assessment was performed before and after their winter training.  (Paper III).  Heart rate variability (HRV) was analyzed from the same cold provocation/recovery sequences (Paper IV). Results:  (Paper I) For the 379 cases of hospitalization for cold-related injury, annual incidences for hypothermia, frostbite, and drowning were 3.4/100,000, 1.5/100,000, and 1.0/100,000 inhabitants, respectively.  Male gender was more frequent for all categories.  Annual frequencies for hypothermia hospitalizations increased during the study period.  Hypothermia degree and distribution of cases were 20 % mild (between 32 and 35ºC), 40% moderate (31.9 to 28ºC), and 24% severe (< 28ºC), while 12% had temperatures over 35.0ºC.  (Paper II) The 207 cases of fatal hypothermia showed an annual incidence of 1.35 per 100,000 inhabitants, 72% in rural areas, 93% outdoors, 40% found within 100 meters of a building.  Paradoxical undressing was documented in 30%.  Ethanol was detected in femoral vein blood in 43%. Contributing co-morbidity was common including heart disease, previous stroke, dementia, psychiatric disease, alcoholism, and recent trauma.  (Paper III) Post-training, baseline fingertip temperatures and cold recovery variables in terms of final rewarming fingertip temperature and vasodilation time increased significantly in moderate and slow rewarmers.  Cold-related injury (frostbite) during winter training occured disproportionately more often in slow rewarmers (4 of the 5 injuries).  (Paper IV) At ‘pre- winter-training’, normal rewarmers had higher power for low frequency and high frequency heart rate variability.  After cold acclimatization (post-training), normal rewarmers showed lower resting power values for the low frequency and high frequency heart rate variability components.  Conclusions: Hypothermia and cold injury continues to cause injury and hospitalization in the northern region of Sweden.  Assessment and management is not standardized across hospitals.  With the identification of groups at high risk for fatal hypothermia, it should be possible to reduce the incidence, particularly for highest risk subjects; rural, living alone, alcohol-imbibing, and psychiatric diagnosis-carrying citizens.  Long-term cold-weather training may affect hand rewarming patters after a cold provocation, and a warmer baseline hand temperature with faster rewarming after a cold provocation may be associated with less general risk for frostbite.  Heart rate variability results support the conclusion that cold adaptation in the autonomic nervous system occurred in both groups, though the biological significance of this is not yet clear.
259

Endocrine and Psychophysiological Correlates of Jealousy and Social Anxiety in Healthy Adults: Elevated Responses to Inter-Male Competition

McCurdy, Bethany H. 01 May 2015 (has links)
Male mammals compete for reproductive access to females. Gaining and maintaining this access can be stressful and anxiety-provoking. In humans, anxiety and associated protective behaviors can manifest as jealousy. Physiological stress is likely to increase in relation to jealousy as it does with anxiety. Hypothetically, higher levels of anxiety and cortisol may indicate, and may even promote, strong territorial or jealous behavior. Chronically elevated cortisol has been shown to be deleterious to prefrontal and hippocampal neurons and result in emotional and stress-response dysregulation. In very anxious and jealous individuals, chronic stress activation could further promote these tendencies via emotional disinhibition. Cortisol production also related to vasopressin (AVP) levels and AVP has been shown to increase mate preference and territoriality. Furthermore, physiological measures may be more valid than self-report of less socially desirable behaviors such as jealousy and anxiety. As a preliminary study, we measured salivary cortisol, heart-rate, and blood pressure in relation to self-reported anxiety and jealousy in healthy men and women in response to threatening male faces paired with smiling female faces. Elevated anxiety positively predicted jealousy in men but not women. Anxiety and jealousy also predicted elevated heart rate and blood pressure. Cortisol levels in response to the threat task and in relation to jealousy approached statistical significance (ps < 0.07) and suggest the need for a larger sample size.
260

Parent and Child Vagal Tone: Examining Parenting Behaviors as Moderators of the Association

Graham, Rebecca 11 August 2015 (has links)
Research indicates that learning how to regulate one’s emotions is critical to successful child development and is associated with adaptive social functioning and psychological adjustment (Dunn & Brown, 1994; Eisenberg, Fabes, Guthrie, & Reiser, 2000; Eisenberg, Fabes, & Murphy, 1996). Children’s emotion regulation abilities are thought to be influenced by both child (e.g., age, temperament) and parent characteristics (e.g., parenting behaviors, parental regulation; Eisenberg, Cumberland, & Spinrad, 1998). Resting heart rate variability (HRV) has emerged as a potentially important biomarker associated with emotion regulation (Porges, 2007; Thayer & Lane, 2000); however, there are still significant gaps in research. In particular, research indicates genetic correlates associated with HRV as well as an important role of parents in children’s emotion socialization, but research has yet to establish a strong link between parent and child HRV. Theoretically, parent and child HRV may be linked but only in specific contexts. For example, parent and child resting HRV may become more or less strongly related in the context of specific parenting behaviors, but research has yet to test this hypothesis. The present study examined the association between parenting behaviors and child resting HF-HRV (i.e., high frequency HRV), the links between parent and child resting HF-HRV, and potential moderating effects of parenting behaviors on the association in youth. Additional analyses examined associations between parent and child vagal regulation. Ninety-seven youth (11-17 years) and their caregivers (n = 81) participated in a physiological assessment and completed questionnaires assessing parenting behaviors. Results indicated that parent’s inconsistent discipline and corporal punishment were negatively associated with their child’s resting HF-HRV while positive parenting and parental involvement were positively associated. Furthermore, parent’s inconsistent discipline and parent’s involvement moderated the relationship between parent and child resting HF-HRV, such that in the context of high inconsistent discipline and high parental involvement, high parent resting HF-HRV was associated with low child resting HF-HRV. Findings add to the literature by providing evidence for the role of parenting behaviors in shaping the development of children’s HF-HRV and indicating that inconsistent discipline and parental involvement may affect the entrainment of HF-HRV in parents and their adolescent children.

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