1,594 research outputs found
Interactions between cardiac activity and conscious somatosensory perception
Fluctuations in the heart's activity can modulate the access of external stimuli to consciousness. The link between perceptual awareness and cardiac signals has been investigated mainly in the visual and auditory domain. Here, we investigated whether the phase of the cardiac cycle and the prestimulus heart rate influence conscious somatosensory perception. We also tested how conscious detection of somatosensory stimuli affects the heart rate. Electrocardiograms (ECG) of 33 healthy volunteers were recorded while applying near‐threshold electrical pulses at a fixed intensity to the left index finger. Conscious detection was not uniformly distributed across the cardiac cycle but significantly higher in diastole than in systole. We found no evidence that the heart rate before a stimulus influenced its detection, but hits (correctly detected somatosensory stimuli) led to a more pronounced cardiac deceleration than misses. Our findings demonstrate interactions between cardiac activity and conscious somatosensory perception, which highlights the importance of internal bodily states for sensory processing beyond the auditory and visual domain
Volumetrical characterization of sheet molding compounds
For a comprehensive study of Sheet Molding Compound (SMC) surfaces, topographical data obtained by chromatic confocal imaging were submitted systematically for the development of a profile model to understand the formation of cavities on the surface. In order to qualify SMC surfaces and to predict their coatability, a characterization of cavities is applied. To quantify the effect of surface modification treatments, a new parameter (Surface Relative Smooth) is presented, applied and probed. The parameter proposed can be used for any surface modification of any solid material. © 2010 by the authors
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Evaluating LAB@FUTURE, a collaborative e-learning Laboratory experiments platform
This paper presents Lab@Future, an advanced e-learning platform that uses novel Information and Communication Technologies to support and expand laboratory teaching practices. For this purpose, Lab@Future uses real and computer generated objects that are interfaced using mechatronic systems, augmented reality, mobile technologies and 3D multi user environments. The main aim is to develop and demonstrate technological support for practical experiments in the following focused disciplines namely: Fluid Dynamics - Science subject in Germany, Geometry - Mathematics subject in Austria, History and Environmental Awareness – Arts and Humanities subjects in Greece and Slovenia. In order to pedagogically enhance the design and functional aspects of this e-learning technology, we are investigating the dialogical operationalisation of learning theories so as to leverage our understanding of teaching and learning practices in the targeted context of deployment. To be able to evaluate the lab@future system in its entire complexity an evaluation methodology including several phases has been developed, performing formative as well as summative evaluations
Neural correlates of conscious tactile perception: An analysis of BOLD activation patterns and graph metrics
Theories of human consciousness substantially vary in the proposed spatial extent of brain activity associated with conscious perception as well as in the assumed functional alterations within the involved brain regions. Here, we investigate which local and global changes in brain activity accompany conscious somatosensory perception following electrical finger nerve stimulation, and whether there are whole-brain functional network alterations by means of graph metrics. Thirty-eight healthy participants performed a somatosensory detection task and reported their decision confidence during fMRI. For conscious tactile perception in contrast to undetected near-threshold trials (misses), we observed increased BOLD activity in the precuneus, the intraparietal sulcus, the insula, the nucleus accumbens, the inferior frontal gyrus and the contralateral secondary somatosensory cortex. For misses compared to correct rejections, bilateral secondary somatosensory cortices, supplementary motor cortex and insula showed greater activations. The analysis of whole-brain functional network topology for hits, misses and correct rejections, did not result in any significant differences in modularity, participation, clustering or path length, which was supported by Bayes factor statistics. In conclusion, for conscious somatosensory perception, our results are consistent with an involvement of (probably) domain-general brain areas (precuneus, insula, inferior frontal gyrus) in addition to somatosensory regions; our data do not support the notion of specific changes in graph metrics associated with conscious experience. For the employed somatosensory submodality of fine electrical current stimulation, this speaks for a global broadcasting of sensory content across the brain without substantial reconfiguration of the whole-brain functional network resulting in an integrative conscious experience
Neural correlates of conscious tactile perception: An analysis of BOLD activation patterns and graph metrics
Theories of human consciousness substantially vary in the proposed spatial extent of brain activity associated with conscious perception as well as in the assumed functional alterations within the involved brain regions. Here, we investigate which local and global changes in brain activity accompany conscious somatosensory perception following electrical finger nerve stimulation, and whether there are whole-brain functional network alterations by means of graph metrics. Thirty-eight healthy participants performed a somatosensory detection task and reported their decision confidence during fMRI. For conscious tactile perception in contrast to undetected near-threshold trials (misses), we observed increased BOLD activity in the precuneus, the intraparietal sulcus, the insula, the nucleus accumbens, the inferior frontal gyrus and the contralateral secondary somatosensory cortex. For misses compared to correct rejections, bilateral secondary somatosensory cortices, supplementary motor cortex and insula showed greater activations. The analysis of whole-brain functional network topology for hits, misses and correct rejections, did not result in any significant differences in modularity, participation, clustering or path length, which was supported by Bayes factor statistics. In conclusion, for conscious somatosensory perception, our results are consistent with an involvement of (probably) domain-general brain areas (precuneus, insula, inferior frontal gyrus) in addition to somatosensory regions; our data do not support the notion of specific changes in graph metrics associated with conscious experience. For the employed somatosensory submodality of fine electrical current stimulation, this speaks for a global broadcasting of sensory content across the brain without substantial reconfiguration of the whole-brain functional network resulting in an integrative conscious experience
Broadband Recordings for LITHOS-CAPP: LITHOspheric Structure of Caledonian, Archaean and Proterozoic Provinces, Sep. 2014 - Oct. 2016, Sweden and Finland
LITHOS-CAPP is the German contribution to the international ScanArray experiment. ScanArray is an array of broadband seismometers with which we aim to study the lithosphere and upper mantle beneath the Scandinavian Mountains and the Baltic Shield. LITHOS-CAPP contributed 20 broadband recording stations from September 2014 to October 2016, 10 in Sweden and 10 in Finland, continuously recordings at 100 samples per second. The stations were deployed by the KIT Geophysical Institute and GFZ section 2.4 (seismology). They form part of the temporary network ScanArrayCore (FDSN network code 1G 2012-2017
Home Manufacture of Drugs: An Online Investigation and a Toxicological Reality Check of Online Discussions on Drug Chemistry
Emerging trends in market dynamics and the use of new psychoactive substances are both a public health concern and a complex regulatory issue. One novel area of investigation is the availability of homemade opioids, amphetamines and dissociatives, and the potential fueling of interest in clandestine home manufacture of drugs via the Internet. We illustrate here how online communal folk pharmacology of homemade drugs on drug website forums may actually inform home manufacture practices or contribute to the reduction of harms associated with this practice. Discrepancies between online information around purification and making homemade drugs safer, and the synthesis of the same substances in a proper laboratory environment, exist. Moderation and shutdown of synthesis queries and discussions online are grounded in drug websites adhering to harm-reduction principles by facilitating discussions around purification of homemade drugs only. Drug discussion forums should consider reevaluating their policies on chemistry discussions in aiming to reach people who cannot or will not refrain from cooking their own drugs with credible information that may contribute to reductions in the harms associated with this practice. © 2017 Taylor & Francis Group, LL
Comparative analysis of 2D and 3D models of turbulent natural convection and thermal surface radiation in closed areas
Turbulent natural convection with surface thermal radiation in air-filled enclosures has been investigated. The equations of conservation of mass, momentum and energy are solved using both finite difference and control volume methods. It should be noted that the working medium is Newtonian and heat conducting fluid, where the Boussinesq approximation is valid. The walls are supposed to be gray, diffuse emitters and reflectors of radiation. The left and right surfaces of the enclosure are isothermal walls, while other surfaces are adiabatic walls. The considered fluid flow is turbulent. The main aim of the present research is to compare the heat transfer process in 2D and 3D enclosures. Detailed results including flow profiles, temperature fields, and average Nusselt numbers have been presented
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