Recovery from stress: The role of perseverative cognition, affect and demanding shift work

Contains fulltext : 150484.pdf (publisher's version ) (Open Access)Radboud Universiteit Nijmegen, 05 februari 2016Promotores : Geurts, S.A.E., Kompier, M.A.J. Co-promotor : Brosschot, J.F.139 p

Thermomechanical fatigue of Sanicro 25 : Material modeling using the finite element method

The report aims to describe the austenitic stainless steel Sanicro 25 from a thermomechanical point of view. The thermal and mechanical properties of the material make it suitable for use in coal – and thermal power plants. By the use of Sanicro 25 it would be possible to bring the efficiency of these plants up while bringing the carbon emissions down.A material model is created from material testing and validated through simulation in the finite element software Abaqus. The model that has been derived describes the material behavior during loading and stress relaxation for the first cycle in a thermomechanical fatigue test well. The unloading part of the cycle however cannot be described correctly by the use of this model.Rostfrit

Music and psychophysiological recovery from stress

Item does not contain fulltextObjective: This experimental study examined whether listening to self-chosen music after stress exposure improves mood, decreases subjective arousal and rumination, and facilitates cardiovascular recovery. Method: Participants (N = 123) were exposed to a mental arithmetic task with harassment to induce stress. Afterward, participants were randomly assigned to one of four "recovery'' conditions where they (1) listened to self-chosen relaxing music, (2) listened to self-chosen happy music, (3) listened to an audio book, or (4) sat in silence. After this 5-minute "recovery manipulation period,'' participants sat in silence for another 5 minutes. Systolic blood pressure, diastolic blood pressure, and heart rate were continuously measured. Results: The recovery conditions caused differences in positive affect (F(3,119) = 13.13, p < .001) and negative affect (F(3,119) = 2.69, p = .049). As expected, mood improved while listening to either relaxing music or happy music. The conditions showed no differences in subjective arousal (F(3,117) = 2.03, p = .11) and rumination (F(3,119) = 1.10, p = .35). Systolic blood pressure recovery, however, differed between the conditions (linear time trend: F(3,116) = 4.50, p = .005; quadratic time trend: F(3,115) = 5.24, p = .002). Listening to both relaxing and happy music delayed systolic blood pressure recovery when compared with both control conditions. Conclusions: Listening to self-selected music is an effective mood enhancer, but it delays blood pressure recovery.9 p

Ironic effects of feedback on contingency of self-worth: Why self-reports of contingency are biased

Contingent self-worth has been studied as an individual differences variable affecting how self-relevant information is processed. We examined the effects of self-relevant information on contingent self-worth as a dependent variable. In Experiment 1 (N = 79, college students), participants’ performance contingency was higher after negative than positive performance feedback. In Experiment 2 (N = 3764, community sample), social approval and appearance contingencies were lower in a social approval condition than in control conditions. Mediation analyses suggested this effect was mediated by enhanced self-esteem. Thus, self-esteem increased due to the very source that participants came to regard as less important: Social approval. Results are explained in terms of sociometer theory and limited introspection abilities: All self-esteem is sensitive to external contingencies, people just become more aware of this when it is threatened

Ironic effects of feedback on contingency of self-worth: Why self-reports of contingency are biased

Contingent self-worth has been studied as an individual differences variable affecting how self-relevant information is processed. We examined the effects of self-relevant information on contingent self-worth as a dependent variable. In Experiment 1 (N = 79, college students), participants’ performance contingency was higher after negative than positive performance feedback. In Experiment 2 (N = 3764, community sample), social approval and appearance contingencies were lower in a social approval condition than in control conditions. Mediation analyses suggested this effect was mediated by enhanced self-esteem. Thus, self-esteem increased due to the very source that participants came to regard as less important: Social approval. Results are explained in terms of sociometer theory and limited introspection abilities: All self-esteem is sensitive to external contingencies, people just become more aware of this when it is threatened.Multivariate analysis of psychological dat

Recovery and well-being among Helicopter Emergency Medical Service (HEMS) pilots

Item does not contain fulltextThis study investigated the effects of a compressed working week with high cognitive and emotional work demands within the population of Dutch Helicopter Emergency Medical Service (HEMS) pilots. Work stressors were measured and levels of well-being were examined before, during and after a series of day and night shifts. Results revealed that (i) the start of a series of day shifts was more taxing for wellbeing than the start of a series of night shifts, (ii) there were no differences in the decrease in well-being during day and night shifts, (iii) distress during shifts was more strongly related to a decrease in wellbeing during night than during day shifts and (iv) it took HEMS pilots more time to recover from a series of night shifts than from a series of day shifts. It is concluded that HEMS pilots should not start earlier during day shifts, nor have longer series of night shifts.8 p

The role of affect and rumination in cardiovascular recovery from stress

Contains fulltext : 99823.pdf (publisher's version ) (Closed access)This study examined the psychological processes that may impede or facilitate cardiovascular recovery. It was hypothesized that cardiovascular recovery would be hampered by negative affect and rumination, and facilitated by positive affect. In an experimental study, stress was elicited by exposing participants (N = 110) to a mental arithmetic task with harassment. After the stress task, affective levels were manipulated via a movie scene with negative, neutral, or positive emotional valence, or without an affect manipulation (control condition). During the entire experiment, heart rate and systolic and diastolic blood pressure levels were measured continuously. Results indicated that blood pressure recovery was hampered by the negative affect manipulation and by rumination. However, the positive affect manipulation did not facilitate blood pressure recovery. No effects were found on heart rate recovery. In sum, the findings emphasize the importance of negative affect and rumination in stress recovery.8 p

Enrichment of skeletal muscle stem cell transplantation using chemotherapeutic drugs.

The BCNU + O6benzylguanine (O6BG) driven selective enrichment strategy was first established for enhanced transplantation of hematopoietic stem cells. This study describes a novel application of this BCNU + O6BG driven selective enrichment strategy in skeletal muscle stem cell transplantation. Furthermore, this study addresses the three main limitations observed in previously reported skeletal muscle stem cell transplantation strategies. Limitation of ineffective donor cells which lack the ability for successful engraftment was overcome by using a heterogeneous population of donor cells which are present during a normal skeletal muscle regeneration response. The limitation of donor cell death upon transplantation as a result of competition from the endogenous stem cells of the host muscles was overcome by elimination of host muscle stem cells with BCNU + O6BG treatment. Efficiency of elimination of host muscle stem cells was further demonstrated by the complete inhibition of a regeneration response up to 3 months in injured, BCNU + O6BG treated muscles. The limitation of localised engraftment as a result of intramuscular injection of donor cells was also addressed. The transplanted donor cells demonstrated the ability to migrate via systemic circulation. This characteristic of the donor cells would allow the transplantation of cells via intraarterial or intravenous delivery which would overcome the limitation of localised engraftment. Finally, application of the BCNU + O6BG driven selective enrichment strategy in skeletal muscle stem cell transplantation demonstrated enhanced engraftment. This is the first reported attempt of enhanced stem cell transplantation in a solid tissue achieved upon application of the BCNU + O6BG driven selective enrichment strategy. This study provides the basis for application of the BCNU + O6BG driven selective enrichment strategy in other tissues where stem cell transplantation is considered

Does unconscious stress play a role in prolonged cardiovascular stress recovery?

Item does not contain fulltextAccording to recent insights, humans might not be aware of a substantial part of their cognitive stress representations while these still have prolonged physiological effects. Unconscious stress' can be measured by implicit affect (IA) tests. It was shown that IA predicts physiological stress responses, in fact better than explicit (conscious') affect. It is not known yet whether IA is associated with concurrent prolonged stress responses. In two studies (n=62 and 123), anger harassment was used to induce stress. Blood pressure (BP) and heart rate (HR) were measured continuously. During BP and HR recovery, IA was measured by an anger' version of the implicit association test (IAT) or the implicit positive and negative affect test (IPANAT). Blood pressure and HR increased during anger harassment and recovery afterwards. When using the IPANAT BP recovery levels were lower when positive IA was high and higher when negative IA was high, independent of explicit affect and rumination. These results were not found using the IAT. These results provide preliminary evidence that physiological stress recovery is associated with IA. This is in line with the theory that unconscious stress is responsible for a possibly considerable part of unhealthy prolonged stress-related physiological activity.9 p