Concurrent Cortical Representations of Function- and Size-Related Object Affordances: An fMRI Study

Previous work has shown that the perception of a graspable object may automatically potentiate actions that are tailored to specific action-related features of the object (e.g., its size) and may be related to its immediate grasping as well as to its long-term, functional use. We investigated the neural correlates of function-and size-related object affordances that may be concurrently potentiated by a graspable object. Participants were lying in a MR scanner holding a large switch in one hand and a small switch in the other hand. They passively attended a large or a small object with clearly separated functional and graspable end that was displayed centrally at an average angle of 45 degrees. Participants responded to the direction of an arrow that was overlaid on the object after a mean period of 1,000 ms after object onset and was pointing to the left or to the right with equal probability. Response times were shorter when the arrow pointed to the functional end of the object and when the responses were made with the switch that was congruent to the size of the perceived object. A clear distinction was found in the representation of function-and size-related affordances; the former was represented in the posterior parietal cortex and the latter in prefrontal, premotor, and primary sensorimotor cortices. We conclude that different aspects of object-directed actions may be automatically potentiated by individual object features and are represented in distinct brain areas

Human left ventral premotor cortex mediates matching of hand posture to object use

Visuomotor transformations for grasping have been associated with a fronto-parietal network in the monkey brain. The human homologue of the parietal monkey region (AIP) has been identified as the anterior part of the intraparietal sulcus (aIPS), whereas the putative human equivalent of the monkey frontal region (F5) is located in the ventral part of the premotor cortex (vPMC). Results from animal studies suggest that monkey F5 is involved in the selection of appropriate hand postures relative to the constraints of the task. In humans, the functional roles of aIPS and vPMC appear to be more complex and the relative contribution of each region to grasp selection remains uncertain. The present study aimed to identify modulation in brain areas sensitive to the difficulty level of tool object - hand posture matching. Seventeen healthy right handed participants underwent fMRI while observing pictures of familiar tool objects followed by pictures of hand postures. The task was to decide whether the hand posture matched the functional use of the previously shown object. Conditions were manipulated for level of difficulty. Compared to a picture matching control task, the tool object - hand posture matching conditions conjointly showed increased modulation in several left hemispheric regions of the superior and inferior parietal lobules (including aIPS), the middle occipital gyrus, and the inferior temporal gyrus. Comparison of hard versus easy conditions selectively modulated the left inferior frontal gyrus with peak activity located in its opercular part (Brodmann area (BA) 44). We suggest that in the human brain, vPMC/BA44 is involved in the matching of hand posture configurations in accordance with visual and functional demands

Brain activity during phonation in women with muscle tension dysphonia : an fMRI study

Objectives. The main objectives of this functional magnetic resonance imaging (fMRI) study are (1) to investigate brain activity during phonation in women with muscle tension dysphonia (MTD) in comparison with healthy controls; and (2) to explain the neurophysiological mechanism of laryngeal hyperfunction/tension during phonation in patients with MTD. Methods. Ten women with MTD and fifteen healthy women participated in this study. The fMRI experiment was carried out using a block design paradigm. Brain activation during phonation and exhalation was analyzed using BrainVoyager software. Results. The statistical analysis of fMRI data has demonstrated that MTD patients control phonation by use of the auditory, motor, frontal, parietal, and subcortical areas similar to phonation control by healthy people. Comparison of phonation tasks in the two groups revealed higher brain activities in the precentral gyrus, inferior, middle and superior frontal gyrus, lingual gyrus, insula, cerebellum, midbrain, and brainstem as well as lower brain activities in the cingulate gyrus, superior and middle temporal gyrus, and inferior parietal lobe in the MTD group. No differences were found between the two groups regarding exhalation control. Conclusions. The findings in this study provide insight into phonation and exhalation control in patients with MTD. The imaging results demonstrated that in patients with MTD, altered (higher/lower) brain activities may result in laryngeal tension and vocal hyperfunction

Nuclear structure of Cu isotopes studied with collinear laser spectroscopy.

This work presents the nuclear spins, magnetic moments, quadrupole momentsand differences in mean square radii of the Cu isotopes 58−75Cu.The collinear laser spectroscopy technique was used. The experimentswere performed at the collinear laser spectroscopy setup COLLAPS atISOLDE, CERN. A detailed overview of the setup and the analysis procedureof laser spectroscopy data is given in this work. A recent technicalimprovement was the installation of the RFQ beam cooler, which allowedto extend the measurements toward more exotic isotopes. The groundstatespin inversion for the odd-A Cu isotopes from spin 3/2 to 5/2 isestablished to occur at 75Cu. This result presents a breakthrough in experimentaland theoretical investigations in this region. The spin-parityof the odd-odd Cu isotopes 72−74Cu is determined to be 2−. The resultingmagnetic moments and quadrupole moments are compared withtheoretical calculations in a f5/2pg9/2 model space and a pf shell modelspace.The magnetic moments of the odd-A Cu isotopes clearly show that excitationsacross the Z = 28 and N = 28 shell gaps need to be includedin the model space to reproduce the experimental trend, providing anotherevidence of the softness of the 56Ni core. The odd-A as well as theodd-odd A Cu isotopes illustrate the sensitivity of the magnetic momentto the detailed composition of the wave function, which makes magneticmoments crucial parameters to evaluate shell model calculations.The quadrupole moments show a minimum in collectivity at N = 40.However, this is not entirely related to the magnitude of the N = 40subshell gap but largely induced by the opposite parity of the g9/2 orbitcompared to the pf shell orbits, which blocks single-particle excitationsacross N = 40. The experimental quadrupole trend does not support anincrease of collectivity beyond N = 40. Theoretical calculations in a pfmodel space appear to underestimate the experimental core polarizationfor the neutron-deficient Cu nuclei.The procedure of extracting the differences in mean square charge radiifrom the measured isotope shifts is given in detail. Comparison of themean square charge radii with the droplet model prediction suggests asignificant collectivity in the Cu isotope chain. A small structural effectat N = 40 is observed.status: publishe

Nuclear structure of Cu isotopes studied with collinear laser spectroscopy

This work presents the nuclear spins, magnetic moments, quadrupole moments and differences in mean square radii of the Cu isotopes $^{58−75}$Cu. The collinear laser spectroscopy technique was used. The experiments were performed at the collinear laser spectroscopy setup COLLAPS at ISOLDE, CERN. A detailed overview of the setup and the analysis procedure of laser spectroscopy data is given in this work. A recent technical improvement was the installation of the RFQ beam cooler, which allowed to extend the measurements toward more exotic isotopes. The groundstate spin inversion for the odd-$A$ Cu isotopes from spin 3/2 to 5/2 is established to occur at $^{75}$Cu. This result presents a breakthrough in experimental and theoretical investigations in this region. The spin-parity of the odd-odd Cu isotopes $^{72−74}$Cu is determined to be 2$^−$. The resulting magnetic moments and quadrupole moments are compared with theoretical calculations in a $f_{5/2}pg_{9/2}$ model space and a pf shell model space. The magnetic moments of the odd-A Cu isotopes clearly show that excitations across the $Z$ = 28 and $N$ = 28 shell gaps need to be included in the model space to reproduce the experimental trend, providing another evidence of the softness of the $^{56}$Ni core. The odd-$A$ as well as the odd-odd $A$ Cu isotopes illustrate the sensitivity of the magnetic moment to the detailed composition of the wave function, which makes magnetic moments crucial parameters to evaluate shell model calculations. The quadrupole moments show a minimum in collectivity at $N$ = 40. However, this is not entirely related to the magnitude of the $N$ = 40 subshell gap but largely induced by the opposite parity of the $g_{9/2}$ orbit compared to the $pf$ shell orbits, which blocks single-particle excitations across $N$ = 40. The experimental quadrupole trend does not support an increase of collectivity beyond $N$ = 40. Theoretical calculations in a $pf$ model space appear to underestimate the experimental core polarization for the neutron-deficient Cu nuclei. The procedure of extracting the differences in mean square charge radii from the measured isotope shifts is given in detail. Comparison of the mean square charge radii with the droplet model prediction suggests a significant collectivity in the Cu isotope chain. A small structural effect at $N$ = 40 is observed

Molecules : indispensable in the decarbonized energy chain

Electricity will become the main energy supplier to deliver energy services to the end consumer, being it residential, commercial or industrial. However, as part of the road to a fully carbon neutral energy system by 2050, molecules as energy carriers will play a key role. The paper describes the challenges for decarbonizing the different energy vectors and how choices are impacting energy efficiency. Two main routes exist to produce carbon-free hydrogen: classic approaches from carbon-based fuels equipped with Carbon Capture and Storage/incorporated in Carbon Capture and Use strategies, blue hydrogen or via electrolysis powered by renewable electric energy, green hydrogen. The direct use of hydrogen as a supplier of energy services to the end user is limited. Due to the specific characteristics of the hydrogen molecule (very light, very low boiling temperature, very low energy density), mobile applications are doubtful. For stationary applications, the need for storage of energy is clearly present, but the required volume and the resulting pressure/temperature needs make hydrogen a poor choice. The same holds for strategic energy storage. Hydrogen-based molecules, can be produced by combining CO2 captured from the air or industrial processes, making hydrogen an essential part of the carbon neutral post 2050 energy system, as an intermediate product. Molecules such as ammonia (NH3) may be used to transport hydrogen over long distances. The analysis leads to conclusions on the need for a clear taxonomy of hydrogen. The basis has to be the carbon content in order to ensure carbon neutrality in the most effective way

Barriers identified regarding Scalability and Replicability of Smart Grid Projects

Goal of this paper is to assess the scalability and replicability of smart grid projects, focusing on the identification of limitations and barriers faced by smart gird project. For this purpose, factors have been identified that influence and condition a project’s scalability and replicability through a review of the state of the art and analysis of smart grid demonstration project. The factors are of technical, economic, and regulatory and social acceptance nature, and they describe requirements for scalability and replicability. Data was collected from on-going European smart grid demonstration project which allowed quantifying the status quo with respect to the scalability and replicability, i.e., to what extent projects take into account these factors. The obtain results allowed the identification of barriers, limitations regarding the scalability and replicability of smart grid projects. In particular, the absence of standards, the physical limits of the existing infrastructure, the absence of cost-benefit analyses and the neglect of varying macroeconomic factors, stakeholder involvement and from the dependency of projects on regional or national regulatory frameworks and market designs.status: publishe