351 research outputs found

    Entwicklung und Untersuchung eines Konzepts zur Nutzung von Indoor-Positioning-Technologie in Systemen für adaptive, mobile Informationsbereitstellung

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    Die dynamische Entwicklung mobiler Systeme macht es erforderlich, adaptive Informationen auf der Grundlage der Position von Objekten bereitzustellen. Im Anwendungsgebiet der Indoor Positioning, bei dem die Signale des globalen Navigationssatellitensystems nicht erreichbar sind, existiert bisher keine Standardlösung für die optimale Umsetzung. Im Rahmen dieser Arbeit wird die Umsetzung anhand von realen und abstrakten Systemen für die adaptive und mobile Bereitstellung von Informationen analysiert und in Bezug auf den medizinischen Bereich vertieft. Dementsprechend wird die Integration mehrerer Positionierungsverfahren in ein System zur Nutzung von Smart Glasses implementiert. Der Entwurf- und Implementierungsprozess basiert auf einer Analyse aktueller Lösungen und Methoden. Abschließend ist das Konzept mit Hilfe einer Anforderungsanalyse, einer Evaluationsstrategie und einer Simulationsumgebung untersucht worden.:1. Einleitung 1 2. Adaptive, mobile Informationsbereitstellung 5 3. Indoor Positioning 10 4. Analyse 18 5. Design und Realisierung 25 6. Evaluation 33 7. Diskussion und Fazit 3

    School Children's Physical Activity, Motor Competence, and Corresponding Self-Perception: A Longitudinal Analysis of Reciprocal Relationships

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    Background: The relationship between engagement in physical activity and the development of motor competence (MC) is considered to be reciprocal and dynamic throughout childhood and adolescence. The 10-month follow-up study aimed to explore this reciprocal relationship and investigated whether the relationship is mediated by the corresponding self-perception of MC (PMC). Methods: A total of 51 children aged between 10 and 11 years (M= 10.27 [0.45]) participated in the study (52.9% boys, 47.1% girls). As an indicator for physical activity, the average vigorous physical activity (VPA) per day was measured by ActiGraph accelerometers. Two aspects of MC and PMC were recorded: self-movement and object movement. Saturated pathway models in a cross-lagged panel design with 2 measurement points were analyzed. Results: Reciprocal and direct relationships between VPA and MC object movement respectively MC self-movement were not found in longitudinal analyses with PMC as a mediator. Indirect effects of MC at t1 on VPA at t2 via PMC were identified (self-movement: β = 0.13, 95% confidence interval, 0.04 to 0.26; object movement: β = 0.14, 95% confidence interval, 0.01 to 0.49). Conclusion: The results highlight the importance of MC and PMC in promoting children’s VPA. However, VPA does not drive the development of MC. This version has not the original pagination, for citations see: doi:10.5281/zenodo.4147498.+repphzhbib2020

    Association of Exercise with Inhibitory Control and Prefrontal Brain Activity Under Acute Psychosocial Stress

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    Psychosocial stress has negative effects on cognition in adolescents. The aim of this study was to investigate whether physical exercise can buffer such effects on inhibitory control and associated cortical brain areas. Forty-two male high school students aged 16-20 years and with either low or high exercise levels performed a Stroop task under stress-free conditions and after the Trier Social Stress Test (TSST). Oxygenation of the dorsolateral prefrontal cortex (DLPFC) was measured with functional near-infrared spectroscopy. For inhibitory control, there was no significant primary effect of condition (; F; (1,40) = 1.09,; p; = 303.,; ηp²; = 0.027) and no significant condition × group interaction (; F; (1,40) = 2.40,; p; = 0.129,; ηp²; = 0.057). For DLPFC oxygenation, a significant primary effect of condition was observed (; F; (1,38) = 6.10,; p; = 0.018,; ηp²; = 0.138). However, the condition × group interaction (; F; (1,38) = 0.05,; p; = 0.823,; ηp²; = 0.001) remained not significant. Adolescents' exercise level was not associated with inhibitory control before and after stress. An impact of stress on a neurocognitive level was observed

    School Children's Physical Activity, Motor Competence, and Corresponding Self-Perception: A Longitudinal Analysis of Reciprocal Relationships

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    Background: The relationship between engagement in physical activity and the development of motor competence (MC) is considered to be reciprocal and dynamic throughout childhood and adolescence. The 10-month follow-up study aimed to explore this reciprocal relationship and investigated whether the relationship is mediated by the corresponding self-perception of MC (PMC). Methods: A total of 51 children aged between 10 and 11 years (M= 10.27 [0.45]) participated in the study (52.9% boys, 47.1% girls). As an indicator for physical activity, the average vigorous physical activity (VPA) per day was measured by ActiGraph accelerometers. Two aspects of MC and PMC were recorded: self-movement and object movement. Saturated pathway models in a cross-lagged panel design with 2 measurement points were analyzed. Results: Reciprocal and direct relationships between VPA and MC object movement respectively MC self-movement were not found in longitudinal analyses with PMC as a mediator. Indirect effects of MC at t1 on VPA at t2 via PMC were identified (self-movement: β = 0.13, 95% confidence interval, 0.04 to 0.26; object movement: β = 0.14, 95% confidence interval, 0.01 to 0.49). Conclusion: The results highlight the importance of MC and PMC in promoting children’s VPA. However, VPA does not drive the development of MC.+repphzhbib2020

    The Influence of an Acute Exercise Bout on Adolescents' Stress Reactivity, Interference Control, and Brain Oxygenation Under Stress

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    Background:High psychosocial stress can impair executive function in adolescents,whereas acute exercise has been reported to benefit this cognitive domain. The aim ofthis study was to investigate whether an acute bout of aerobic exercise improves theinhibitory aspect of executive function and the associated dorsolateral prefrontal cortex(DLPFC) oxygenation when under stress.Methods:Sixty male high school students aged 16–20 years performed a Strooptask (baseline condition) and were randomly assigned to an exercise group (30 min onergometer at 70% of maximum heart rate) and a control group (30 min of reading).Subsequently, all participants underwent a modified Trier Social Stress Test, whichincluded a Stroop task under enhanced stress. The Stroop tasks in both conditionswere combined with functional near-infrared spectroscopy to record changes in DLPFCoxygenation in response to the tasks. Stress reactivity was measured with salivasamples (cortisol, alpha-amylase), heart rate monitoring, and anxiety scores.Results:All stress parameters indicated increases in response to the stressor(p<0.001), with higher alpha-amylase [t(58) =−3.45,p= 0.001,d= 1.93] andanxiety [t(58) =−2.04,p= 0.046,d= 0.53] reactions in the control compared to theexercise group. Controlling for these two parameters, repeated measures analyses ofcovariance targeting changes in Stroop interference scores showed no main effect ofstress [F(1,58) = 3.80,p= 0.056,ηp2= 0.063] and no stress×group interaction[F(1,58) = 0.43,p= 0.517,ηp2= 0.008]. Similarly, there was no main effect ofstress [F(1,58) = 2.38,p= 0.128,ηp2= 0.040] and no stress×group interaction[F(1,58) = 2.80,p= 0.100,ηp2= 0.047] for DLPFC oxygenation.Conclusion:Our study confirms potentially health-enhancing effects of acute exerciseon some of the physiological and psychological stress reactivity indicators. However,our data do not support the notion of an effect on interference control and DLPFCactivation under stress

    Psychometric Properties and Convergent Validity of the Shirom-Melamed Burnout Measure in Two German-Speaking Samples of Adult Workers and Police Officers

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    Burnout is considered an occupation-related psychological syndrome consisting of emotional, physical, and cognitive exhaustion. To assess dimensions of burnout, the Shirom-Melamed Burnout Measure (SMB; M; ) is widely used, but its validity and reliability have rarely been examined in adult samples. The aim of this study is to examine the psychometric properties of the German version of the SMB; M; in two independent samples of adults. In total, 311 adult workers and 201 police officers completed the SMB; M; , and questionnaires related to perceived stress and mental well-being. Descriptive statistics, internal consistency, convergent validity, and factorial validity were assessed for both samples, separately for male and female participants. The German SMB; M; had adequate psychometric properties and sufficient convergent validity. In confirmatory factor analyses, we found a good fit for both the first- and second-order model. Furthermore, measurement invariance across gender was observed in both samples. Although the SMB; M; is a popular instrument among burnout researchers, this study demonstrates for the first time that the SMB; M; can be considered a valid and reliable tool to assess burnout symptoms in both male and female adults and across different professional groups. Furthermore, with its 14 items, the SMB; M; is a succinct and economic self-assessment tool for symptoms of burnout

    Does Cardiorespiratory Fitness Moderate the Association between Occupational Stress, Cardiovascular Risk, and Mental Health in Police Officers?

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    Background:; Chronic exposure to occupational stress may lead to negative health consequences. Creating less stressful work environments and making employees physically and psychologically more resilient against stress are therefore two major public health concerns. This study examined whether cardiorespiratory fitness moderated the association between occupational stress, cardiovascular risk, and mental health.; Methods:; Stress was assessed via the Effort-Reward Imbalance and Job Demand-Control models in 201 police officers (36% women, Mage = 38.6 years). Higher levels of blood pressure, blood lipids, blood sugar, and unfavorable body composition were considered as cardiovascular risk factors. Burnout, insomnia and overall psychological distress were used as mental health indicators. Cardiorespiratory fitness was assessed with a submaximal bicycle test.; Results:; High cardiorespiratory fitness levels were associated with a reduced cardiometabolic risk, whereas high stress levels were associated with better mental health. Among participants who perceived a high Effort-Reward Imbalance, those with high fitness levels showed lower overall cardiovascular risk scores than their colleagues with low fitness levels.; Conclusions:; Work health programs for police officers should consider the early screening of burnout, sleep disturbances, and overall mental wellbeing. To increase cardiovascular health, including fitness tests in routine health checks and promoting physical activity to further increase cardiorespiratory fitness appears worthwhile

    Does Cardiorespiratory Fitness Buffer Stress Reactivity and Stress Recovery in Police Officers? A Real-Life Study

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    High levels of cardiorespiratory fitness have the potential to buffer against physical and mental health impairments, which can result from exposure to occupational stress. Police officers are especially at risk of high psychosocial stress; therefore, effective intervention strategies are warranted. Given this background, the purpose of the present study was to examine whether police officers with different levels of cardiorespiratory fitness differ with regard to their (a) physiological stress reactivity during acute real life stress situations, and (b) physiological recovery related to acute and chronic work stress. In total, 201 police officers took part in this study (M = 38.6 years, SD = 10.1, 35.8% females). Officers were contacted eight times on a smartphone during their workday, and asked to report their current level of positive and negative affect, as well as feelings of stress and anger. Physiological stress responses and recovery (heart rate variability) were assessed using Movisens EcgMove3 devices. The Åstrand bicycle ergometer test was used to assess participants' cardiorespiratory fitness. Chronic work stress was assessed using the effortreward imbalance model and the job strain model. Multilevel modeling was used to test buffering effects of cardiorespiratory fitness on physiological stress reactivity. Linear regression was applied to test stress-buffering effects of cardiorespiratory fitness on physiological recovery. Results showed lowered physiological stress reactivity to acute work stress in officers with higher levels of cardiorespiratory fitness. However, these results were not consistent, with no effects occurring for feelings of anger, positive affect, and negative affect. Chronic work stress (effort-reward imbalance) was related to lower physiological recovery. Cardiorespiratory fitness was positively related to physiological recovery. Data did not support interactions between work stress and cardiorespiratory fitness on physiological recovery. To some extent, cardiorespiratory fitness seems to have the potential to buffer stress reactivity in police officers in acute stress situations. Therefore, we encourage promoting fitness programs which aim to enhance cardiorespiratory fitness in stressful occupations such as law enforcement.+repphzhbib2020

    Does Cardiorespiratory Fitness Buffer Stress Reactivity and Stress Recovery in Police Officers? A Real-Life Study

    Get PDF
    High levels of cardiorespiratory fitness have the potential to buffer against physical and mental health impairments, which can result from exposure to occupational stress. Police officers are especially at risk of high psychosocial stress; therefore, effective intervention strategies are warranted. Given this background, the purpose of the present study was to examine whether police officers with different levels of cardiorespiratory fitness differ with regard to their (a) physiological stress reactivity during acute real-life stress situations, and (b) physiological recovery related to acute and chronic work stress. In total, 201 police officers took part in this study (M = 38.6 years, SD = 10.1, 35.8% females). Officers were contacted eight times on a smartphone during their workday, and asked to report their current level of positive and negative affect, as well as feelings of stress and anger. Physiological stress responses and recovery (heart rate variability) were assessed using Movisens EcgMove3 devices. The Åstrand bicycle ergometer test was used to assess participants' cardiorespiratory fitness. Chronic work stress was assessed using the effort-reward imbalance model and the job strain model. Multilevel modeling was used to test buffering effects of cardiorespiratory fitness on physiological stress reactivity. Linear regression was applied to test stress-buffering effects of cardiorespiratory fitness on physiological recovery. Results showed lowered physiological stress reactivity to acute work stress in officers with higher levels of cardiorespiratory fitness. However, these results were not consistent, with no effects occurring for feelings of anger, positive affect, and negative affect. Chronic work stress (effort-reward imbalance) was related to lower physiological recovery. Cardiorespiratory fitness was positively related to physiological recovery. Data did not support interactions between work stress and cardiorespiratory fitness on physiological recovery. To some extent, cardiorespiratory fitness seems to have the potential to buffer stress reactivity in police officers in acute stress situations. Therefore, we encourage promoting fitness programs which aim to enhance cardiorespiratory fitness in stressful occupations such as law enforcement. Improvements in cardiorespiratory fitness might further enhance physiological recovery from chronic work stress, which is thought to improve cardiovascular health

    Zastosowanie stentu przełykowego do leczenia pooperacyjnej przetoki zespolenia przełykowo-żołądkowego - opis przypadku

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    W niniejszej pracy przedstawiono przypadek leczenia pooperacyjnej nieszczelności zespolenia przełykowo-żołądkowego z wykorzystaniem powlekanego stentu. Omówiono wady i zalety postępowania
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