Differential associations of health literacy with Austrian adolescents' tobacco and alcohol use.

OBJECTIVES: Tobacco use and alcohol use have their origin in adolescence, and risky use of these substances is amongst the leading preventable causes of morbidity and mortality. Health literacy (HL) encompasses the skills that are decisive to make appropriate health decisions in this context. Given the paucity of evidence on the link between HL and adolescents' health behaviors, the present study examined overall HL and different components of HL and their associations with smoking and alcohol use among 13 to 17-year-old Austrian students. STUDY DESIGN: Data were obtained from a national survey carried out in Austria (N = 4219; 56% females) as part of the Health Behaviour in School-aged Children: World Health Organization (WHO) collaborative cross-national study. METHODS: We tested two structural equation models, one including the overall HL scale as the predictor and one with the three subscales of HL 'finding,' 'understanding and appraising,' and 'applying' health-related information as predictors of smoking and alcohol use. RESULTS: Although overall HL was related to all indicators of adolescents' smoking and drinking, the three HL components had differential effects on these behaviors. The easier it was for the participants to 'understand and appraise' and 'apply' health-related information, the less frequently they had smoked and drunk alcohol and the less was the amount of alcohol they had consumed. Contrarily, the easier it was for the participants to 'find' information, the more they had smoked and drunk alcohol. CONCLUSIONS: Our results indicate that availability of health-related information may be insufficient on its own to prevent or reduce risky substance use. This is of particular importance for the development and improvement of primary prevention programs targeting adolescent populations.

Spatially coupled catalytic ignition of CO oxidation on Pt: mesoscopic versus nano-scale.

Spatial coupling during catalytic ignition of CO oxidation on µm-sized Pt(hkl) domains of a polycrystalline Pt foil has been studied in situ by PEEM (photoemission electron microscopy) in the 10(-5) mbar pressure range. The same reaction has been examined under similar conditions by FIM (field ion microscopy) on nm-sized Pt(hkl) facets of a Pt nanotip. Proper orthogonal decomposition (POD) of the digitized FIM images has been employed to analyze spatiotemporal dynamics of catalytic ignition. The results show the essential role of the sample size and of the morphology of the domain (facet) boundary in the spatial coupling in CO oxidation.

The Role of Defects in the Local Reaction Kinetics of CO Oxidation on Low-Index Pd Surfaces.

The role of artificially created defects and steps in the local reaction kinetics of CO oxidation on the individual domains of a polycrystalline Pd foil was studied by photoemission electron microscopy (PEEM), mass spectroscopy (MS), and scanning tunneling microscopy (STM). The defects and steps were created by STM-controlled Ar+ sputtering and the novel PEEM-based approach allowed the simultaneous determination of local kinetic phase transitions on differently oriented µm-sized grains of a polycrystalline sample. The independent (single-crystal-like) reaction behavior of the individual Pd(hkl) domains in the 10-5 mbar pressure range changes upon Ar+ sputtering to a correlated reaction behavior, and the reaction fronts propagate unhindered across the grain boundaries. The defect-rich surface shows also a significantly higher CO tolerance as reflected by the shift of both the global (MS-measured) and the local (PEEM-measured) kinetic diagrams toward higher CO pressure.

Silicon Oxide Surface Segregation in CO Oxidation on Pd: An in situ PEEM, MS and XPS Study.

ABSTRACT: The effect of silicon oxide surface segregation on the locally-resolved kinetics of the CO oxidation reaction on individual grains of a polycrystalline Pd foil was studied in situ by PEEM, MS and XPS. The silicon oxide formation induced by Si-impurity segregation at oxidizing conditions, was monitored by XPS and its impact on the global and local (spatially resolved) kinetics of the CO oxidation was determined by MS and PEEM. The results reveal a drastic inhibiting effect of silicon oxide on the Pd reactivity towards CO oxidation, manifested both in the collapse of the global CO2 formation rate and in the modified local reactive properties of individual Pd micrograins. The presence of adsorbed oxygen on the Pd surface effectively enhances the silicon segregation to the Pd surface.

Mapping the local reaction kinetics by PEEM: CO oxidation on individual (100)-type grains of Pt foil.

The locally-resolved reaction kinetics of CO oxidation on individual (100)-type grains of a polycrystalline Pt foil was monitored in situ using photoemission electron microscopy (PEEM). Reaction-induced surface morphology changes were studied by optical differential interference contrast microscopy and atomic force microscopy (AFM). Regions of high catalytic activity, low activity and bistability in a (p,T)-parameter space were determined, allowing to establish a local kinetic phase diagram for CO oxidation on (100) facets of Pt foil. PEEM observations of the reaction front propagation on Pt(100) domains reveal a high degree of propagation anisotropy both for oxygen and CO fronts on the apparently isotropic Pt(100) surface. The anisotropy vanishes for oxygen fronts at temperatures above 465 K, but is maintained for CO fronts at all temperatures studied, i.e. in the range of 417 to 513 K. A change in the front propagation mechanism is proposed to explain the observed effects.

[Strategies of data reduction in computer-assisted EEG analysis in the time domain--measurement of theoretical aspects and redundancy relations within and between various strategies of data reduction]. / Strategien der Datenreduktion bei computerassistierter EEG-Analyse im Zeitbereich--Messtheoretische Gesichtspunkte und Redundanzverhältnisse innerhalb und zwischen verschiedenen Strategien der Datenreduktion.

The enormous amount of data after performing computer assisted EEG-analysis makes necessary reduction methods. Different strategies have been proposed. Traditionally the distribution of frequencies is shown by using frequency bands. The aim of this paper is to compare different strategies of data reduction regarding frequency distribution and to discuss results concerning validity. Three data reduction methods and their mutual relations will be discussed. The classification with regard to frequency bands, the computation of quartils of the frequency spectrum and the search for prominent frequencies. It will be shown wether or not calculated values are redundant and reflect identical information (latent dimensions).

[Influence of isosorbiddinitrate on hemodynamics at rest and during exercise (author's transl)]. / Beeinflussung der Ruhe- und Belastungshämodynamik durch Isosorbiddinitrat (ISDN). Untersuchungen an Patienten 3 Wochen nach akutem transmuralem Myokardinfarkt.

23 patients with acute transmural myocardial infarction were exercised (4 min. 30 Watt) at the end of the hospital period (14-26 days after administration) (probatory exercise). This test was repeated identically after 5 mg of ISDN; again hemodynamic measurements were done (heart rate, arterial pressure, pulmonary artery pressure, cardiac output). 60% of the investigated patients had elevated (above 20 mm Hg) wedge pressures (pulmonary diastolic pressure) during exercise. The elevated PA-pressure was lowered significantly by administration of ISDN. In Group II (with exercise PADP above 20 mm Hg) this reduction of preload improved ventricular performance significantly. In Group I (PADP ex below 20 mm Hg) reduction of the preload worsened ventricular performance (not significant). Heart rate rose at rest and was reduced during exercise after ISDN. Arterial pressure was lower after ISDN as well as during exercise. ISDN proved to be a valuable drug in the postinfarction period even in patients free of angina pectoris since it may help to normalize disturbed hemodynamics (which can only be detected by exercise testing in many cases).