22 research outputs found
A spatially varying coefficient model for mapping PM10 air quality at the European scale
Particulate matter (PM) air quality in Europe has improved substantially over the past decades, but it still poses a significant threat to human health. Accurate regional scale maps of PM10 concentrations are needed for monitoring progress in mitigation strategies and monitoring compliance with statutory limit values. Chemistry transport models (CTM) use emission databases and simulate the transport and deposition of pollutants. They deliver such maps but are known to be inaccurate. A promising approach is to use geostatistics to model the relationship between the in situ observations and the CTM. This has been shown to be more accurate than using either observations or CTM's alone. This paper presents a spatially varying coefficients (SVC) geostatistical model as an extension of the standard spatially varying intercept (SVI) geostatistical model. SVC allowed the regression coefficient to vary spatially according to a covariance function, the parameters of which were estimated from the data. It was built as a Bayesian hierarchical model and implemented using Markov chain Monte Carlo. The procedure was applied to Airbase PM10 observations and LOTOS-EUROS simulated PM10 for central, southern and eastern Europe. Model-fit diagnostics showed that SVC delivered a better fit to the data than SVI. Mapping the spatially varying coefficients allowed identification of the locations where the CTM performed well or poorly. This could be used for objective CTM evaluation purposes. The posterior predictive simulations were also used to map median PM10 concentrations as well as the probability of exceeding the 50 μg m−3 EU daily PM10 concentration threshold. Although posterior median prediction accuracy was similar for SVI and SVC, SVC better modelled the process and yielded narrower credible intervals. As such, SVC was more appropriate for quantifying uncertainty and for mapping threshold exceedances. The resulting maps may be used to guide air quality assessment and mitigation strategies, including those related to health impact
Symposium: Classical and instrumental conditioning. presented at the 34th annual German experimental psychology meeting
Sensitization and aversive conditioning: Effects on the startle reflex and electrodermal responding
Latent class growth analyses reveal overrepresentation of dysfunctional fear conditioning trajectories in patients with anxiety-related disorders compared to controls
Recent meta-analyses indicated differences in fear acquisition and extinction between patients with anxiety-related disorders and comparison subjects. However, these effects are small and may hold for only a subsample of patients. To investigate individual trajectories in fear acquisition and extinction across patients with anxiety-related disorders (N = 104; before treatment) and comparison subjects (N = 93), data from a previous study (Duits et al., 2017) were re-analyzed using data-driven latent class growth analyses. In this explorative study, subjective fear ratings, shock expectancy ratings and startle responses were used as outcome measures. Fear and expectancy ratings, but not startle data, yielded distinct fear conditioning trajectories across participants. Patients were, compared to controls, overrepresented in two distinct dysfunctional fear conditioning trajectories: impaired safety learning and poor fear extinction to danger cues. The profiling of individual patterns allowed to determine that whereas a subset of patients showed trajectories of dysfunctional fear conditioning, a significant proportion of patients (≥50 %) did not. The strength of trajectory analyses as opposed to group analyses is that it allows the identification of individuals with dysfunctional fear conditioning. Results suggested that dysfunctional fear learning may also be associated with poor treatment outcome, but further research in larger samples is needed to address this question
Affective Computer-Generated Stimulus Exposure: Psychophysiological Support for Increased Elicitation of Negative Emotions in High and Low Fear Subjects
Latent class growth analyses reveal overrepresentation of dysfunctional fear conditioning trajectories in patients with anxiety-related disorders compared to controls
Recent meta-analyses indicated differences in fear acquisition and extinction between patients with anxiety-related disorders and comparison subjects. However, these effects are small and may hold for only a subsample of patients. To investigate individual trajectories in fear acquisition and extinction across patients with anxiety-related disorders (N = 104; before treatment) and comparison subjects (N = 93), data from a previous study (Duits et al., 2017) were re-analyzed using data-driven latent class growth analyses. In this explorative study, subjective fear ratings, shock expectancy ratings and startle responses were used as outcome measures. Fear and expectancy ratings, but not startle data, yielded distinct fear conditioning trajectories across participants. Patients were, compared to controls, overrepresented in two distinct dysfunctional fear conditioning trajectories: impaired safety learning and poor fear extinction to danger cues. The profiling of individual patterns allowed to determine that whereas a subset of patients showed trajectories of dysfunctional fear conditioning, a significant proportion of patients (≥50 %) did not. The strength of trajectory analyses as opposed to group analyses is that it allows the identification of individuals with dysfunctional fear conditioning. Results suggested that dysfunctional fear learning may also be associated with poor treatment outcome, but further research in larger samples is needed to address this question
Supplementary Material for: Die Effekte interozeptiver Expositionsübungen in der Kognitiven Verhaltenstherapie von Panikstörung mit Agoraphobie
<b><i>Hintergrund:</i></b> In der Kognitiven Verhaltenstherapie (KVT) der Panikstörung mit Agoraphobie (PD/AG) werden häufig Körperübungen zur Symptomprovokation (interozeptive Exposition) eingesetzt, jedoch liegen kaum systematische, empirische Untersuchungen zu Wirkung und Wirkweise dieser Übungen vor. Ziel der vorliegenden Studie war die Charakterisierung individueller Reaktionen auf interozeptive Übungen sowie die mit der Wiederholung der Übungen verbundenen Veränderungen dieser Reaktionen. <b><i>Patienten und Methoden:</i></b> Selbstberichtdaten zu ausgelösten Körpersymptomen sowie Symptom- und Angststärken von 301 Patienten mit PD/AG, die verschiedene interozeptive Übungen durchführten, wurden ausgewertet. Die Durchführung der interozeptiven Exposition erfolgte im Rahmen einer manualisierten KVT des Psychotherapieverbundes «Panik-Netz». <b><i>Ergebnisse:</i></b> Interozeptive Exposition löste Körpersymptome und damit verbunden Angst aus. Am häufigsten wurden vestibuläre, respiratorische und kardiovaskuläre Symptome ausgelöst. Die stärkste Symptomausprägung verbunden mit der stärksten Angst erzeugten die Übungen «Drehen», «Hyperventilieren» und «Strohhalmatmung». Übungswiederholung bewirkte eine Reduktion der Symptom- und Angststärken, insbesondere die Übungen «Drehen», «Strohhalmatmung» und «Hyperventilieren». <b><i>Diskussion und Schlussfolgerungen:</i></b> Interozeptive Exposition ist gut geeignet zur Auslösung von Körpersymptomen und zur Reduktion der damit verbundenen Symptom- und Angststärke, insbesondere über die Übungen «Drehen», «Hyperventilieren» und «Strohhalmatmung». Zur größeren Angst- und Symptomstärkenreduktion empfiehlt sich eine hohe Wiederholungsrate. Die Relevanz respiratorischer, vestibulärer und kardiovaskulärer Symptome für den Behandlungserfolg sollte weiterführend untersucht werden