Different pathways of the formation of highly oxidized multifunctional organic compounds (HOMs) from the gas-phase ozonolysis of β-caryophyllene

The gas-phase mechanism of the formation of highly oxidized multifunctional organic compounds (HOMs) from the ozonolysis of β-caryophyllene was investigated in a free-jet flow system at atmospheric pressure and a temperature of 295 ± 2 K. Reaction products, mainly highly oxidized RO2 radicals containing up to 14 oxygen atoms, were detected using chemical ionization – atmospheric pressure interface – time-of-flight mass spectrometry with nitrate and acetate ionization. These highly oxidized RO2 radicals react with NO, NO2, HO2 and other RO2 radicals under atmospheric conditions forming the first-generation HOM closed-shell products. Mechanistic information on the formation of the highly oxidized RO2 radicals is based on results obtained with isotopically labelled ozone (18O3) in the ozonolysis reaction and from hydrogen/deuterium (H/D) exchange experiments of acidic H atoms in the products. The experimental findings indicate that HOM formation in this reaction system is considerably influenced by the presence of a double bond in the RO2 radicals primarily formed from the β-caryophyllene ozonolysis. Three different reaction types for HOM formation can be proposed, allowing for an explanation of the detected main products: (i) the simple autoxidation, corresponding to the repetitive reaction sequence of intramolecular H-abstraction of a RO2 radical, RO2  →  QOOH, and subsequent O2 addition, next forming a peroxy radical, QOOH + O2  →  R′O2; (ii) an extended autoxidation mechanism additionally involving the internal reaction of a RO2 radical with a double bond forming most likely an endoperoxide and (iii) an extended autoxidation mechanism including CO2 elimination. The individual reaction steps of the reaction types (ii) and (iii) are uncertain at the moment. From the product analysis it can be followed that the simple autoxidation mechanism accounts only for about one-third of the formed HOMs. Time-dependent measurements showed that the HOM formation proceeds at a timescale of 3 s or less under the concentration regime applied here. The new reaction pathways represent an extension of the mechanistic understanding of HOM formation via autoxidation in the atmosphere, as recently discovered from laboratory investigations on monoterpene ozonolysis

Perspektiven auf die Waraosprache und das Waraosprechen

Die Arbeit untersucht verschiedene Perspektiven auf die Waraosprache und das Waraosprechen in Venezuela. Dabei konzentriert sie sich auf drei auptperspektiven: die der Warao-Sprecher, die der katholischen Kapuzinermissionare und die des venezolanischen Staates. Grundlage für die Arbeit sind eigene Feldforschungsaufenthalte im Orinokodelta, Venezuela in den Jahren 1999 - 2004. Ergebnis der Arbeit ist, dass es eine "Waraosprache" als universelles Objekt der Sicht aller Akteure nicht gibt. Vor allem die Sprecher selbst stellen das Konzept des "Waraosprechen" im Rahmen ihrer mündlichen Kultur in den Mittelpunkt. So unterstützt die vorliegende Arbeit die amerindische Sichtweise, dass es keine allgemeingültige Realität gibt, sondern nur viele Wahrheiten

A brief patient-reported outcome instrument for primary care: German translation and validation of the Measure Yourself Medical Outcome Profile (MYMOP)

Background: Measure Yourself Medical Outcome Profile (MYMOP) is a patient-generated outcome instrument capable of measuring effects from a wide range of health care interventions. This paper reports the translation of this instrument into German (MYMOP-D) and the assessment of validity and sensitivity to change for the MYMOP-D. The instrument was piloted in a German primary care context. Methods: The translation process was conducted according to international guidelines. Recruited patients of both general practitioners and non-medical Complementary and Alternative Medicine (CAM) practitioners (“Heilpraktiker”) in the German state of Baden-Wuerttemberg completed a questionnaire comprised of the MYMOP-D and the EQ-5D. Responses were analysed to assess construct validity. For assessing the instrument’s sensitivity to change, patients received the MYMOP-D again after four weeks at which point they were also asked for their subjective views on change of symptoms. Correlation between MYMOP-D and EQ-5D and sensitivity to change as gradient in score change and as standardized response mean (SRM) were calculated. Results: 476 patients from general practices and 91 patients of CAM practitioners were included. Construct validity of the MYMOP-D was given with a correlation of r = .47 with the EQ-5D. Sensitivity to change for subjective change of symptoms could only be analysed for improvement or no change of symptoms, as only 12 patients reported deterioration of symptoms. Results showed the expected smooth gradient with 2.2, 1.3, and 0.5 points of change for large, little improvement and no change, respectively. SRM for MYMOP-D Profile Score was 0.88. Conclusions: The MYMOP-D shows excellent construct validity. It is able to detect changes when symptoms in patients improve or remain unchanged. Deterioration of symptoms could not be evaluated due to too few data. With its brevity and simplicity, it might be an important tool for enhancing patient-centred care in the German health care context

EEG-neurofeedback as a tool to modulate cognition and behaviour: a review tutorial

Neurofeedback is attracting renewed interest as a method to self-regulate one’s own brain activity to directly alter the underlying neural mechanisms of cognition and behaviour. It promises new avenues as a method for cognitive enhancement in healthy subjects, but also as a therapeutic tool. In the current article, we present a review tutorial discussing key aspects relevant to the development of EEG neurofeedback studies. In addition, the putative mechanisms underlying neurofeedback learning are considered. We highlight both aspects relevant for the practical application of neurofeedback as well as rather theoretical considerations related to the development of new generation protocols. Important characteristics regarding the set-up of a neurofeedback protocol are outlined in a step-by-step way. All these practical and theoretical considerations are illustrated based on a protocol and results of a frontal-midline theta up-regulation training for the improvement of executive functions. Not least, assessment criteria for the validation of neurofeedback studies as well as general guidelines for the evaluation of training efficacy are discussed

Memory-matches evoke human gamma-responses

BACKGROUND: Human brain activity in the gamma frequency range has been shown to be a correlate of numerous cognitive functions like attention, perception and memory access. More specifically, gamma activity has been found to be enhanced when stimuli are stored in or match with short-term memory (STM). We tested the hypothesis that gamma activity is also evoked when stimuli match representations in long-term-memory (LTM). EEG was recorded from 13 subjects performing a choice reaction task. Visual stimuli were either known real-world objects with a memory representation or novel configurations never seen before. RESULTS: All stimuli evoked an early gamma response which was maximal over occipital electrodes. This evoked gamma activity was significantly larger for items that matched memory templates. CONCLUSIONS: Therefore, we argue that gamma activity results from the feedback from memory into perception systems. This assumption seems to be true for STM as well as LTM

Die Weltmeisterschaft der Berufe:. Analyse der „WorldSkills-Wettbewerbe“ aus einer technikdidaktischen

Alle 2 Jahre finden die WorldSkills in einem anderen Land, auf einem anderen Kontinent statt. Wenngleich diese „Weltmeisterschaft der Berufe“ in Deutschland wenig bekannt und eher eine Insider-Veranstaltung ist, hat sie im internationalen Berufsbildungsraum große Bedeutung. Im Folgenden wird zunächst erklärt, was die WorldSkills sind, was ihre Ideen und Ziele sind und woher sie kommen. Anschließend erfolgt eine skizzenartige Gegenüberstellung der weltweiten Berufsbildungsansätze jener Staaten, welche sich regelmäßig an den World­Skills beteiligen. Auf Basis von Wettbewerbs-Ergebnissen wird ein Ländervergleich vorgestellt und differenziert erörtert, welche Staaten in welchentechnischen Berufssegmenten sich in den WorldSkills wie positionieren“. Dabei wird deutlich, dass die WorldSkills-Wettbewerbe wertvolle standardisierte Datenmaterialien liefern, die auf globaler Ebene erhoben werden und hierbei wertvolle Grundlagen liefern, die von der Forschung für vergleichende Studien genutzt werden können. Die WorldSkills erheben nicht den Anspruch einer „Berufsbildungs-Pisa“. Zu inkonsistent sind die Ausgangsbedingungen der Teilnehmenden und zu wenig kontrollierbar sind die hier entscheidenden Prädiktoren. Dies wird auch mit dem erklärten Ziel der World­­Skills-Wettbewerbe untermauert, „to showcase excellence“, bezogen auf Individuen, nicht Bildungs-systeme. Deutlich wird aber aus den Befunden, dass technisch-berufliche Bildung im internationalen Raum einen hohen Stellenwert hat und, dass sich hierbei unsere Duale Ausbildung auf Augenhöhe mit tertiären Bildungsformaten behaupten kann. Dies zeigen auch die abgerufenen Leistungsniveaus in den Wettbewerben, die sich auf dem EQR-Level von 5-6 bewegen.Schlüsselwörter: WorldSkills, internationaler Vergleich, technische Beruf

Does adult ADHD interact with COMT val 158 met genotype to influence working memory performance?

Peer reviewedPostprin

Filling the void - enriching the feature space of successful stopping

The ability to inhibit behavior is crucial for adaptation in a fast changing environment and is commonly studied with the stop signal task. Current EEG research mainly focuses on the N200 and P300 ERPs and corresponding activity in the theta and delta frequency range, thereby leaving us with a limited understanding of the mechanisms of response inhibition. Here, 15 functional networks were estimated from time-frequency transformed EEG recorded during processing of a visual stop signal task. Cortical sources underlying these functional networks were reconstructed, and a total of 45 features, each representing spectrally and temporally coherent activity, were extracted to train a classifier to differentiate between go and stop trials. A classification accuracy of 85.55% for go and 83.85% for stop trials was achieved. Features capturing fronto-central delta- and theta activity, parieto-occipital alpha, fronto-central as well as right frontal beta activity were highly discriminating between trial-types. However, only a single network, comprising a feature defined by oscillatory activity below 12 Hz, was associated with a generator in the opercular region of the right inferior frontal cortex and showed the expected associations with behavioral inhibition performance. This study pioneers by providing a detailed ranking of neural features regarding their information content for stop and go differentiation at the single-trial level, and may further be the first to identify a scalp EEG marker of the inhibitory control network. This analysis allows for the characterization of the temporal dynamics of response inhibition by matching electrophysiological phenomena to cortical generators and behavioral inhibition performanc

Modified Light Use Efficiency Model for Assessment of Carbon Sequestration in Grasslands of Kazakhstan: Combining Ground Biomass Data and Remote-sensing

A modified light use efficiency (LUE) model was tested in the grasslands of central Kazakhstan in terms of its ability to characterize spatial patterns and interannual dynamics of net primary production (NPP) at a regional scale. In this model, the LUE of the grassland biome (n) was simulated from ground-based NPP measurements, absorbed photosynthetically active radiation (APAR) and meteorological observations using a new empirical approach. Using coarse-resolution satellite data from the Sea-viewing Wide Field-of-view Sensor (SeaWiFS), monthly NPP was calculated from 1998 to 2008 over a large grassland region in Kazakhstan. The modelling results were verified against scaled up plot-level observations of grassland biomass and another available NPP data set derived from a field study in a similar grassland biome. The results indicated the reliability of productivity estimates produced by the model for regional monitoring of grassland NPP. The method for simulation of n suggested in this study can be used in grassland regions where no carbon flux measurements are accessible

The impact of task relevance and degree of distraction on stimulus processing

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