Evaluating Aftereffects of Short-Duration Transcranial Random Noise Stimulation on Cortical Excitability

A 10-minute application of highfrequency (100–640 Hz) transcranial random noise stimulation (tRNS) over the primary motor cortex (M1) increases baseline levels of cortical excitability, lasting around 1 hr poststimulation Terney et al. (2008). We have extended previous work demonstrating this effect by decreasing the stimulation duration to 4, 5, and 6 minutes to assess whether a shorter duration of tRNS can also induce a change in cortical excitability. Single-pulse monophasic transcranial magnetic stimulation (TMS) was used to measure baseline levels of cortical excitability before and after tRNS. A 5- and 6-minute tRNS application induced a significant facilitation. 4-minute tRNS produced no significant aftereffects on corticospinal excitability. Plastic after effects after tRNS on corticospinal excitability require a minimal stimulation duration of 5 minutes. However, the duration of the aftereffect of 5-min tRNS is very short compared to previous studies using tRNS. Developing different transcranial stimulation techniques may be fundamental in understanding how excitatory and inhibitory networks in the human brain can be modulated and how each technique can be optimised for a controlled and effective application

Threatening joy : examining the process underlying concordant and divergent reactions to in-group and out-group emotions

Zahlreiche Studien zeigen, dass Menschen kongruente affektive Reaktionen auf die emotionalen Gesichtsausdrücke von Anderen zeigen: Positive Ausdrücke lösen positive affektive Reaktionen aus, und negative Ausdrücke negative Reaktionen. Es wurde argumentiert, dass diese Reaktionen – zumindest zum Teil – durch die Intention ausgelöst werden, welche durch einen emotionalen Ausdruck signalisiert wird. Diese Argumentation legt nahe, dass eine spezifische Emotion eine spezifische Intention ausdrückt, was wiederum zu einer spezifischen Reaktion führt. Wir nehmen jedoch an, dass der Zusammenhang zwischen emotionalem Ausdruck, Intention, und affektiver Reaktion viel flexibler ist: In Abhängigkeit von sozialen und kontextuellen Faktoren kann der gleiche emotionale Ausdruck unterschiedliche Intentionen ausdrücken und dadurch unterschiedliche Reaktionen auslösen. Solch ein sozialer Faktor, der die Interpretation eines emotionalen Gesichtsausdrucks beeinflusst, könnte die Gruppenzugehörigkeit der Person sein, welche die Emotion zeigt. Da Gruppenzugehörigkeit die Beziehung zwischen Menschen beeinflusst, beeinflusst sie auch das Licht, in dem die Emotion gesehen wird. Wenn die Person, welche die Emotion zeigt, und die Person, welche sie wahrnimmt, der gleichen Gruppe angehören, ist die Beziehung zwischen ihnen freundliche und kooperativ; folglich wird auch die Intention in diesem Licht gesehen und eine kongruente Reaktion auslösen. Falls jedoch die Person, welche die Emotion zeigt, und die Person, welche sie wahrnimmt, unterschiedlichen Gruppen angehören, ist die Beziehung zwischen ihnen negative und kompetitiv. Die Intention wird entsprechend auch in diesem Licht gesehen und kann daher eine divergente Reaktion auslösen. Diese Annahme wurde in den Experimenten für diese Dissertation untersucht. Die Ergebnisse zeigen, dass Annäherungs- und Vermeidungsreaktionen auf Emotionen der Eigen- und Fremdgruppe tatsächlich von der Intention beeinflusst werden: Emotionen (Freude, Angst), die von Eigengruppenmitgliedern gezeigt wurden, lösten kongruente Annäherungs- und Vermeidungsreaktionen aus. Emotionale Ausdrücke (Freude, Angst) der Fremdgruppe aktivierten jedoch divergente Annäherungs- und Vermeidungsreaktionen. Da Annäherungs- und Vermeidungsreaktionen durch die Intention einer Emotion beeinflusst werden, unterstützen diese Ergebnisse unsere Annahme, dass die Gruppenzugehörigkeit beeinflusst, welche Intention aus einem emotionalen Ausdruck abgeleitet wird. Diese Schlussfolgerung wird zusätzlich durch Experiment unterstützt, welches auf der Reversed Correlation Technique basiert. Die Ergebnisse zeigen, dass die mentale Repräsentation von Lächeln gezeigt von Eigengruppenmitgliedern mit positiven Intentionen assoziiert ist, und das Lächeln von Fremdgruppenmitgliedern mit negativen Intentionen. Zusammengefasst zeigen die Ergebnisse, dass Gruppenzugehörigkeit automatische affektive Reaktionen auf Emotionen beeinflusst. Zusätzlich liefern sie Evidenz, dass dieser Effekt durch den Einfluss der Beziehung zwischen demjenigen, der die Emotion zeigt, und demjenigen, der sie wahrnimmt, auf die Interpretation der Intention verursacht wird.Numerous studies examining affective reactions to emotional expressions find that humans show concordant reactions to the emotions of others: Positive facial expressions activate positive affective reactions whereas negative facial expressions activate negative ones. It has been argued that these reactions are – at least in part – triggered by the intention signaled by the emotional expression. This arguing suggests that each emotion signals a specific intention leading to a specific reaction. However, we argue that the link between emotional expression, intention, and affective reaction is much more flexible: Depending on situational and social factors, the same emotional expression can be interpreted as signaling different intentions and therefore trigger different reactions. One of these social factors influencing the interpretation of an emotion might be the group membership of the expresser of the emotion. Since group membership influences the relationship between individuals, it influences the light in which the intention of the emotional expression is seen. If expresser and perceiver of an emotion share group membership, their relationship will be friendly and cooperative; accordingly, the intention signaled by the emotional expression will be seen in this light and elicit a concordant reaction. On the contrary, if expresser and perceiver are members of different groups, they will have a negative and competitive relationship. As a result, the intention signaled by this emotional expression should be interpreted in this light and might therefore elicit a divergent reaction. This assumption was examined in the experiments conducted for this thesis. The results show that approach and avoidance reactions to in-group and out-group emotions are indeed influenced by the intention signaled by the emotion: Emotions (happiness and fear) expressed by the in-group elicited concordant approach and avoidance reactions. Emotional expressions (happiness and fear) shown by out-group members, in contrast, elicited divergent approach and avoidance reactions. Since approach and avoidance reactions are influenced by the intention of the emotion, these results support our arguing that group membership influences which intention is inferred from an emotional expression. This conclusion is supported further by an experiment employing the reversed correlation technique. The results demonstrate that the mental representations of in-group smiles are associated with benevolent intentions and that of out-group smiles with malevolent ones. In sum, employing different paradigms, groups, and dependent variables, our results show that group membership influences automatic affective reactions to emotions. Furthermore, they provide evidence that this effect is caused by an influence of the relationship between expresser and perceiver of an emotion on the interpretation of the intention signaled by the emotional expression

Social Message Account or Processing Conflict Account – Which Processes Trigger Approach/Avoidance Reaction to Emotional Expressions of In- and Out-Group Members?

Faces are characterized by the simultaneous presence of several evaluation-relevant features, for example, emotional expression and (prejudiced) ethnicity. The social message account (SMA) hypothesizes the immediate integration of emotion and ethnicity. According to SMA, happy in-group faces should be interpreted as benevolent, whereas happy out-group faces should be interpreted as potentially malevolent. By contrast, fearful in-group faces should be interpreted as signaling an unsafe environment, whereas fearful out-group faces should be interpreted as signaling inferiority. In contrast, the processing conflict account (PCA) assumes that each face conveys two rather independent evaluative features, emotion and ethnicity. Thus, stimuli might be either affectively congruent or incongruent, and thereby exert influences on behavior. The article reviews the evidence with regard to the two accounts before reporting an experiment that aims at disentangling them. In an approach/avoidance task (AAT), either happy/fearful faces of German and Turks were presented or happy/fearful faces of young and old persons. There are prejudices against Turk/Middle-eastern persons (in Germany) as well as against old persons. For SMA, the two prejudices are of different type; thus prediction for the AAT diverge for the two group conditions. In contrast, for PCA both group features (i.e., Turk ethnicity and old age) are negative features (in comparison to their counterparts) which are affectively congruent or incongruent to the emotional expression. Hence, the results pattern in the AAT should be comparable for the two group conditions. In accordance with SMA but in contrast to PCA, we found different patterns for the two group conditions

Theta-gamma cross-frequency transcranial alternating current stimulation over the trough impairs cognitive control

Cognitive control is a mental process, which underlies adaptive goal-directed decisions. Previous studies have linked cognitive control to electrophysiological fluctuations in the theta band and theta-gamma cross-frequency coupling (CFC) arising from the cingulate and frontal cortices. Yet, to date the behavioral consequences of different forms of theta-gamma CFC remain elusive. Here, we studied the behavioral effects of the theta-gamma CFC via transcranial alternating current stimulation (tACS) designed to stimulate the frontal and cingulate cortices in humans. Using a double-blind, randomized, repeated measures study design, 24 healthy participants were subjected to three active and one control CFC-tACS conditions. In the active conditions, 80 Hz gamma tACS was coupled to 4 Hz theta tACS. Specifically, in two of the active conditions, short gamma bursts were coupled to the delivered theta cycle to coincide with either its peaks or troughs. In the third active condition, the phase of a theta cycle modulated the amplitude of the gamma oscillation. In the fourth, control protocol, 80 Hz tACS was continuously superimposed over the 4 Hz tACS, therefore lacking any phase-specificity in the CFC. During the 20-minute of stimulation, the participants performed a Go/NoGo monetary reward- and punishment-based instrumental learning task. A Bayesian hierarchical logistic regression analysis revealed that relative to the control, the peak-coupled tACS had no effects on the behavioral performance, whereas the trough-coupled tACS and, to a lesser extent, amplitude-modulated tACS reduced performance in conflicting trials. Our results suggest that cognitive control depends on the phase-specificity of the theta-gamma CFC

IMPACT OF ANEMIA ON CLINICAL OUTCOME IN PATIENTS WITH ATRIAL FIBRILLATION UNDERGOING PERCUTANEOUS CORONARY INTERVENTION: INSIGHTS FROM THE AFCAS REGISTRY

OBJECTIVES: Anaemia has an adverse impact on the outcome in the general patient population undergoing percutaneous coronary intervention (PCI). The aim of this study was to analyse the impact of anaemia on the 12-month clinical outcome of patients with atrial fibrillation (AF) undergoing PCI and therefore requiring intense antithrombotic treatment. We hypothesised that anaemia might be associated with a worse outcome and more bleeding in these anticoagulated patients. SETTING: Data were collected from 17 secondary care centres in Europe. PARTICIPANTS: Consecutive patients with AF undergoing PCI were enrolled in the prospective, multicenter AFCAS (Atrial Fibrillation undergoing Coronary Artery Stenting) registry. Altogether, 929 patients participated in the study. Preprocedural haemoglobin concentration was available for 861 (92.7%; 30% women). The only exclusion criteria were inability or unwillingness to give informed consent. Anaemia was defined as a haemoglobin concentration of <12 g/dL for women and <13 g/dL for men. OUTCOME MEASURES: The primary endpoint was occurrence of major adverse cardiac and cerebrovascular events (MACCE) or bleeding events. RESULTS: 258/861 (30%) patients had anaemia. Anaemic patients were older, more often had diabetes, higher CHA(2)DS(2)-VASc scores, prior history of heart failure, chronic renal impairment and acute coronary syndrome. Anaemic patients had more MACCE than non-anaemic (29.1% vs 19.4%, respectively, p=0.002), and minor bleeding events (7.0% vs 3.3%, respectively, p=0.028), with a trend towards more total bleeding events (25.2% vs 21.7%, respectively, p=0.059). No difference was observed in antithrombotic regimens at discharge. In multivariate analysis, anaemia was an independent predictor of all-cause mortality at 12-month follow-up (hazard ratio 1.62, 95% CI 1.05 to 2.51, p=0.029). CONCLUSIONS: Anaemia was a frequent finding in patients with AF referred for PCI. Anaemic patients had a higher all-cause mortality, more thrombotic events and minor bleeding events. Anaemia seems to be an identification of patients at risk for cardiovascular events and death. TRIAL REGISTRATION: ClinicalTrials.gov number NCT00596570

Arbeitsbezogenes sedentäres Verhalten

Hintergrund Sedentäres Verhalten ist mit einem erhöhten Risiko für chronische Krankheiten und einer höheren Gesamtmortalität assoziiert. Arbeitsbezogenes Sitzen hat einen großen Anteil am täglichen sedentären Verhalten, insbesondere bei Büroangestellten. Ziel der Arbeit In dieser Studie sollte untersucht werden, wie viel Zeit bei verschiedenen Aufgaben am Arbeitsplatz und beim Pendeln von Verwaltungsangestellten einer Universitätsklinik in Deutschland im Sitzen verbracht wird. Material und Methoden Eine fragebogengestützte Querschnittsstudie mit Verwaltungsangestellten des Universitätsklinikums Regensburg wurde durchgeführt, um arbeitsbezogenes sedentäres Verhalten zu untersuchen. Ergebnisse Die Studienpopulation bestand aus 159 Teilnehmenden (54,1 % Frauen, 51,6 % älter als 40 Jahre), was einer Antwortquote von 26 % entspricht. Die durchschnittliche tägliche Sitzzeit am Arbeitsplatz betrug im Median 7,0 h (Interquartilsbereich [IQR] 6,0–7,5 h) und fand hauptsächlich bei der Computerarbeit statt (57,3 %). Die mittlere Stehzeit bei der Arbeit betrug im Median 0,8 h (IQR 0,3–1,4 h). Verwaltungsangestellte verbrachten während des Pendelns im Median 0,7 h (IQR 0,3–1,0 h) pro Tag im Sitzen. Die Teilnehmenden waren der Ansicht, dass langes und ununterbrochenes Sitzen negative (69,6 %) oder eher negative (29,7 %) Auswirkungen auf die Gesundheit hat. Diskussion Verwaltungspersonal in Krankenhäusern verbringt einen großen Teil der täglichen Arbeitszeit mit sedentärem Verhalten. Maßnahmen, die es ermöglichen, sowohl im Sitzen als auch im Stehen zu arbeiten, können zu einer Verringerung der arbeitsbedingten Sitzzeit führen und damit die Gesundheit am Arbeitsplatz und im weiteren Sinne die öffentliche Gesundheit verbessern

Photosynthesis in C3-C4 intermediate Moricandia species.

Evolution of C4 photosynthesis is not distributed evenly in the plant kingdom. Particularly interesting is the situation in the Brassicaceae, because the family contains no C4 species, but several C3-C4 intermediates, mainly in the genus Moricandia Investigation of leaf anatomy, gas exchange parameters, the metabolome, and the transcriptome of two C3-C4 intermediate Moricandia species, M. arvensis and M. suffruticosa, and their close C3 relative M. moricandioides enabled us to unravel the specific C3-C4 characteristics in these Moricandia lines. Reduced CO2 compensation points in these lines were accompanied by anatomical adjustments, such as centripetal concentration of organelles in the bundle sheath, and metabolic adjustments, such as the balancing of C and N metabolism between mesophyll and bundle sheath cells by multiple pathways. Evolution from C3 to C3-C4 intermediacy was probably facilitated first by loss of one copy of the glycine decarboxylase P-protein, followed by dominant activity of a bundle sheath-specific element in its promoter. In contrast to recent models, installation of the C3-C4 pathway was not accompanied by enhanced activity of the C4 cycle. Our results indicate that metabolic limitations connected to N metabolism or anatomical limitations connected to vein density could have constrained evolution of C4 in Moricandia

A new instrument to measure high value, cost-conscious care attitudes among healthcare stakeholders: Development of the MHAQ

Background: Residents have to learn to provide high value, cost-conscious care (HVCCC) to counter the trend of excessive healthcare costs. Their learning is impacted by individuals from different stakeholder groups within the workplace environment. These individuals' attitudes toward HVCCC may influence how and what residents learn. This study was carried out to develop an instrument to reliably measure HVCCC attitudes among residents, staff physicians, administrators, and patients. The instrument can be used to assess the residency-training environment. Method: The Maastricht HVCCC Attitude Questionnaire (MHAQ) was developed in four phases. First, we conducted exploratory factor analyses using original data from a previously published survey. Next, we added nine items to strengthen subscales and tested the new questionnaire among the four stakeholder groups. We used exploratory factor analysis and Cronbach's alphas to define subscales, after which the final version of the MHAQ was constructed. Finally, we used generalizability theory to determine the number of respondents (residents or staff physicians) needed to reliably measure a specialty attitude score. Results: Initial factor analysis identified three subscales. Thereafter, 301 residents, 297 staff physicians, 53 administrators and 792 patients completed the new questionnaire between June 2017 and July 2018. The best fitting subscale composition was a three-factor model. Subscales were defined as high-value care, cost incorporation, and perceived drawbacks. Cronbach's alphas were between 0.61 and 0.82 for all stakeholders on all subscales. Sufficient reliability for assessing national specialty attitude (G-coefficient > 0.6) could be achieved from 14 respondents. Conclusions: The MHAQ reliably measures individual attitudes toward HVCCC in different stakeholders in health care contexts. It addresses key dimensions of HVCCC, providing content validity evidence. The MHAQ can be used to identify frontrunners of HVCCC, pinpoint aspects of residency training that need improvement, and benchmark and compare across specialties, hospitals and regions

Face-based Smoothed Finite Element Method for Real-time Simulation of soft tissue

International audienceIn soft tissue surgery, a tumor and other anatomical structures are usually located using the preoperative CT or MR images. However, due to the deformation of the concerned tissues, this information suffers from inaccuracy when employed directly during the surgery. In order to account for these deformations in the planning process, the use of a bio-mechanical model of the tissues is needed. Such models are often designed using the finite element method (FEM), which is, however, computationally expensive, in particular when a high accuracy of the simulation is required. In our work, we propose to use a smoothed finite element method (S-FEM) in the context of modeling of the soft tissue deformation. This numerical technique has been introduced recently to overcome the overly stiff behavior of the standard FEM and to improve the solution accuracy and the convergence rate in solid mechanics problems. In this paper, a face-based smoothed finite element method (FS-FEM) using 4-node tetrahedral elements is presented. We show that in some cases, the method allows for reducing the number of degrees of freedom, while preserving the accuracy of the discretization. The method is evaluated on a simulation of a cantilever beam loaded at the free end and on a simulation of a 3D cube under traction and compression forces. Further, it is applied to the simulation of the brain shift and of the kidney's deformation. The results demonstrate that the method outperforms the standard FEM in a bending scenario and that has similar accuracy as the standard FEM in the simulations of brain shift and kidney deformation