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Introduction
Attempts to improve cognitive abilities via transcranial direct current stimulation (tDCS) have led to ambiguous results, likely due to the method's susceptibility to methodological and inter-individual factors. Conventional tDCS, i.e., using an active electrode over brain areas associated with the targeted cognitive function and a supposedly passive reference, neglects stimulation effects on entire neural networks.
Methods
We investigated the advantage of frontoparietal network stimulation (right prefrontal anode, left posterior parietal cathode) against conventional and sham tDCS in modulating working memory (WM) capacity dependent transfer effects of a single-session distractor inhibition (DIIN) training. Since previous results did not clarify whether electrode montage drives this individual transfer, we here compared conventional to frontoparietal and sham tDCS and reanalyzed data of 124 young, healthy participants in a more robust way using linear mixed effect modeling.
Results
The interaction of electrode montage and WM capacity resulted in systematic differences in transfer effects. While higher performance gains were observed with increasing WM capacity in the frontoparietal stimulation group, low WM capacity individuals benefited more in the sham condition. The conventional stimulation group showed subtle performance gains independent of WM capacity.
Discussion
Our results confirm our previous findings of WM capacity dependent transfer effects on WM by a single-session DIIN training combined with tDCS and additionally highlight the pivotal role of the specific electrode montage. WM capacity dependent differences in frontoparietal network recruitment, especially regarding the parietal involvement, are assumed to underlie this observation.
This article examines public service resilience during the COVID-19 pandemic and studies the switch to telework due to social distancing measures. We argue that the pandemic and related policies led to increasing demands on public organisations and their employees. Following the job demands-resources model, we argue that resilience only can arise in the presence of resources for buffering these demands. Survey data were collected from 1,189 German public employees, 380 participants were included for analysis. The results suggest that the public service was resilient against the crisis and that the shift to telework was not as demanding as expected.
Introduction:
Reactive oxygen and nitrogen species (RONS) are produced as a response to exercise and play a part in guiding the adaptive response to physical training.
Exercise in the heat has been shown to further increase accumulation of RONS in systemic circulation; however, a high antioxidative response or heat acclimatization mechanisms could attenuate this response.
In a previous study, we found reduced RONS concentrations in trained athletes following strenuous cycling in the heat. Therefore, this secondary analysis assessed whether these reduced RONS serum concentrations are induced by an increased serum antioxidant capacity.
Methods:
Twelve male cyclists (V?O2peak: 60 +/- 4 ml center dot kg-1 center dot min-1) completed a 60-minute constant workload trial (55% peak power output, ambient temperature 30.4 +/- 0.6 degrees C) with and without ice vest in a randomized order.
The core body temperature (Tcore) was measured by an ingestible capsule. Blood samples were collected before and after each trial to determine superoxide dismutase (SOD) and catalase (CAT) activity, total antioxidant capacity (TAC) and RONS.
Due to the absence of between-group differences, data of both conditions were pooled. Results: Tcore statistically increased (p < 0.001) over the experimental trials (+6.0 +/- 1.6%, effect size (ES) = 5.6). Concentrations of RONS (-17.2 +/- 15.5%, p < 0.001, ES = 1.0) and TAC (-8.9 +/- 22.9%, p = 0.04, ES = 0.7) statistically decreased, while the activity of CAT (+15.5 +/- 84.0%, p = 0.90, ES = 0.04) and SOD (+9.2 +/- 58.7%, p = 0.98, ES = 0.01) remained unchanged.
Conclusions:
Reduced serum RONS concentrations after strenuous cycling in the heat were not associated with upregulation of serum antioxidant capacity in trained athletes.
The prooxidant-antioxidant balance may rather be regulated at a myocellular level and should be further assessed in future studies.
Kollaborative, partizipative Instrumente zur Krisenbekämpfung haben in den letzten Jahren zunehmend an Aufmerksamkeit gewonnen. Ein Beispiel hierfür ist der #WirVsVirus-Hackathon, der als Reaktion auf die COVID-19-Pandemie durchgeführt wurde und über 28.000 Teilnehmer:innen erreichte. Bislang wurden die Auswirkungen solch groß angelegter, kollaborativer Ansätze zur Krisenbewältigung auf staatliches Krisenmanagement nur selten untersucht. Diese Studie analysiert den Hackathon und die daraus entstandenen Projekte aus der Perspektive des Open Governance-Paradigmas. Auf Grundlage von neun Experteninterviews untersuchen wir, wie sich digitale Open Governance auf die Regierungsfähigkeit und Legitimität in Krisenzeiten auswirkt. Unsere Analyse zeigt, dass digitale Open Governance zur Leistungsfähigkeit und Legitimität staatlichen Handelns in Krisenzeiten beitragen kann, da solche Projekte eine breite und diverse Teilnehmerschaft mobilisieren und in kurzer Zeit bürgerzentrierte, nutzbare Lösungen für krisenbezogene Probleme entwickeln können. Dem stehen allerdings Zweifel an der langfristigen Beständigkeit der Projekte, ihrer Skalierbarkeit, sowie Risiken hinsichtlich der Legitimität und Rechenschaftspflicht entgegen.
A mathematical model of working-memory capacity limits is proposed on the key assumption of mutual interference between items in working memory. Interference is assumed to arise from overwriting of features shared by these items. The model was fit to time-accuracy data of memory-updating tasks from four experiments using nonlinear mixed effect (NLME) models as a framework. The model gave a good account of the data from a numerical and a spatial task version. The performance pattern in a combination of numerical and spatial updating could be explained by variations in the interference parameter: assuming less feature overlap between contents from different domains than between contents from the same domain, the model can account for double dissociations of content domains in dual-task experiments. Experiment 3 extended this idea to similarity within the verbal domain. The decline of memory accuracy with increasing memory load was steeper with phonologically similar than with dissimilar material, although processing speed was faster for the similar material. The model captured the similarity effects with a higher estimated interference parameter for the similar than for the dissimilar condition. The results are difficult to explain with alternative models, in particular models incorporating time-based decay and models assuming limited resource pools.