The Measurement of Language Lateralization with Functional Transcranial Doppler and Functional MRI: A Critical Evaluation

Cerebral language lateralization can be assessed in several ways. In healthy subjects, functional MRI (fMRI) during performance of a language task has evolved to be the most frequently applied method. Functional transcranial Doppler (fTCD) may provide a valid alternative, but has been used rarely. Both techniques have their own strengths and weaknesses and as a result may be applied in different fields of research. Until now, only one relatively small study (n = 13) investigated the correlation between lateralization indices (LIs) measured by fTCD and fMRI and showed a remarkably high correlation. To further evaluate the correlation between LIs measured with fTCD and fMRI, we compared LIs of 22 healthy subjects (12 left- and 10 right-handed) using the same word generation paradigm for the fTCD as for the fMRI experiment. LIs measured with fTCD were highly but imperfectly correlated with LIs measured with fMRI (Spearman's rho = 0.75, p < 0.001). The imperfectness of the correlation can partially be explained by methodological restrictions of fMRI as well as fTCD. Our results suggest that fTCD can be a valid alternative for fMRI to measure lateralization, particularly when costs or mobility are important factors in the study design

e-XPlore: A High-Pressure Solid Oxide Cell Electrolyser in a Sea Container for Offshore Power-to-X Applications

Green hydrogen and synthesis gases are one of the main energy carriers in our attempts to combat global warming and to fulfill the transition of our fossil fuel-based society and industrial activities to carbon neutral alternatives. One of the promising technologies for the production of these gases is the high temperature electrolysis with solid oxide cells (SOCs). At the German Aerospace Center’s (DLR) Institute of Engineering Thermodynamics we experimentally investigate how SOC stacks1 and modules2 (up to 120 kW input) and use transient system simulations3 to develop operation strategies. Particularly when syngas is needed by downstream processes at elevated pressures, it can be advantageous to pressurize the electrolysis as well. Therefore, DLR is building up a transportable test environment called e-XPlore4 for an experimental analysis of a pressured electrolysis system. It comprises a system built in a 40 foot-sea container with an SOC module in a pressure vessel and includes almost all the required auxiliary components for nearly self-sufficient operation, such as cooling water, air supply, climate system, gas heaters, controls and safety system. The system only requires tap water, renewable electricity and some gases like hydrogen and nitrogen for heat-up or emergency cases. Steam electrolysis and co-electrolysis can be performed for hydrogen and syngas production with pressures up to 25 bar, an operating temperature of ca. 900 °C, and with a maximum electrical power input of 10 kW. This system supplies the synthesis gas for downstream processes, such as Fischer-Tropsch-synthesis to produce synthetic fuels within a Power-to-X context. This presentation will showcase the latest updates of planning and engineering of this system, as well as the relevant technical challenges. Operation strategies for different operating points will also be discussed. Furthermore, the off-shore application near a wind farm in the German North Sea as part of the H2Mare5 project will be presented

Shape and volume changes of the superior lateral ventricle after electroconvulsive therapy measured with ultra-high field MRI

The subventricular zone (SVZ) of the lateral ventricles harbors neuronal stem cells in adult mammals. Rodent studies report neurogenic effects in the SVZ of electroconvulsive stimulation. We hypothesize that if this finding translates to depressed patients undergoing electroconvulsive therapy (ECT), this would be reflected in shape changes at the SVZ. Using T1-weighted MR images acquired at ultra-high field strength (7T), the shape and volume of the ventricles were compared from pre to post ECT after 10 ECT sessions (in patients twice weekly) or 5 weeks apart (controls) using linear mixed models with age and gender as covariates. Ventricle shape significantly changed and volume significantly decreased over time in patients for the left ventricle, but not in controls. The decrease in volume of the ventricles was associated to a decrease in depression scores, and an increase in the left dentate gyrus, However, the shape changes of the ventricles were not restricted to the neurogenic niche in the lateral walls of the ventricles, providing no clear evidence for neurogenesis as sole explanation of volume changes in the ventricles after ECT

Operation of a Solid Oxide Fuel Cell Reactor with Multiple Stacks in a Pressured System with Fuel Gas Recirculation

Large-scale modular solid oxide fuel cell (SOFC) reactors composed of multiple stacks are regarded as an efficient form of power generation and important for the global energy transition. However, such an arrangement leads to several operational challenges, and methods are required for handling such challenges and understanding their sources. Hence, a test rig for the examination of a 30 kW SOFC reactor with multiple stacks, for operation near real system conditions, is built. The test rig, which allows operation at elevated pressure, is equipped with a high-temperature blower that recirculates the fuel gas at SOFC reactor temperature. In a measurement campaign, fuel gas, reactant conversion, and pressure are varied in stationary and transient experiments. The experimental results showed that the operating conditions of the individual stacks of large SOFC reactors vary largely due to flow distribution and heat losses. Methods for the investigation of these critical characteristic parameters are derived from the experimental results. Furthermore, the impact of pressurization and fuel gas recirculation on the SOFC reactor is analyzed. This publication shows the need to understand the behavior of large SOFC reactors with multiple stacks to increase the performance and robustness of complete process systems

Interrogating Associations Between Polygenic Liabilities and Electroconvulsive Therapy Effectiveness

Background: Electroconvulsive therapy (ECT) is the most effective treatment for severe major depressive episodes (MDEs). Nonetheless, firmly established associations between ECT outcomes and biological variables are currently lacking. Polygenic risk scores (PRSs) carry clinical potential, but associations with treatment response in psychiatry are seldom reported. Here, we examined whether PRSs for major depressive disorder, schizophrenia (SCZ), cross-disorder, and pharmacological antidepressant response are associated with ECT effectiveness. Methods: A total of 288 patients with MDE from 3 countries were included. The main outcome was a change in the 17-item Hamilton Depression Rating Scale scores from before to after ECT treatment. Secondary outcomes were response and remission. Regression analyses with PRSs as independent variables and several covariates were performed. Explained variance (R 2) at the optimal p-value threshold is reported. Results: In the 266 subjects passing quality control, the PRS-SCZ was positively associated with a larger Hamilton Depression Rating Scale decrease in linear regression (optimal p-value threshold = .05, R 2 = 6.94%, p < .0001), which was consistent across countries: Ireland (R 2 = 8.18%, p = .0013), Belgium (R 2 = 6.83%, p = .016), and the Netherlands (R 2 = 7.92%, p = .0077). The PRS-SCZ was also positively associated with remission (R 2 = 4.63%, p = .0018). Sensitivity and subgroup analyses, including in MDE without psychotic features (R 2 = 4.42%, p = .0024) and unipolar MDE only (R 2 = 9.08%, p < .0001), confirmed the results. The other PRSs were not associated with a change in the Hamilton Depression Rating Scale score at the predefined Bonferroni-corrected significance threshold. Conclusions: A linear association between PRS-SCZ and ECT outcome was uncovered. Although it is too early to adopt PRSs in ECT clinical decision making, these findings strengthen the positioning of PRS-SCZ as relevant to treatment response in psychiatry

Genetic Dissection of Acute Ethanol Responsive Gene Networks in Prefrontal Cortex: Functional and Mechanistic Implications

Background Individual differences in initial sensitivity to ethanol are strongly related to the heritable risk of alcoholism in humans. To elucidate key molecular networks that modulate ethanol sensitivity we performed the first systems genetics analysis of ethanol-responsive gene expression in brain regions of the mesocorticolimbic reward circuit (prefrontal cortex, nucleus accumbens, and ventral midbrain) across a highly diverse family of 27 isogenic mouse strains (BXD panel) before and after treatment with ethanol. Results Acute ethanol altered the expression of ~2,750 genes in one or more regions and 400 transcripts were jointly modulated in all three. Ethanol-responsive gene networks were extracted with a powerful graph theoretical method that efficiently summarized ethanol\u27s effects. These networks correlated with acute behavioral responses to ethanol and other drugs of abuse. As predicted, networks were heavily populated by genes controlling synaptic transmission and neuroplasticity. Several of the most densely interconnected network hubs, including Kcnma1 and Gsk3β, are known to influence behavioral or physiological responses to ethanol, validating our overall approach. Other major hub genes like Grm3, Pten and Nrg3 represent novel targets of ethanol effects. Networks were under strong genetic control by variants that we mapped to a small number of chromosomal loci. Using a novel combination of genetic, bioinformatic and network-based approaches, we identified high priority cis-regulatory candidate genes, including Scn1b,Gria1, Sncb and Nell2. Conclusions The ethanol-responsive gene networks identified here represent a previously uncharacterized intermediate phenotype between DNA variation and ethanol sensitivity in mice. Networks involved in synaptic transmission were strongly regulated by ethanol and could contribute to behavioral plasticity seen with chronic ethanol. Our novel finding that hub genes and a small number of loci exert major influence over the ethanol response of gene networks could have important implications for future studies regarding the mechanisms and treatment of alcohol use disorders

Quantitative trait loci for sensitivity to ethanol intoxication in a C57BL/6J × 129S1/SvImJ inbred mouse cross

Individual variation in sensitivity to acute ethanol (EtOH) challenge is associated with alcohol drinking and is a predictor of alcohol abuse. Previous studies have shown that the C57BL/6J (B6) and 129S1/SvImJ (S1) inbred mouse strains differ in responses on certain measures of acute EtOH intoxication. To gain insight into genetic factors contributing to these differences, we performed quantitative trait locus (QTL) analysis of measures of EtOH-induced ataxia (accelerating rotarod), hypothermia, and loss of righting reflex (LORR) duration in a B6 × S1 F2 population. We confirmed that S1 showed greater EtOH-induced hypothermia (specifically at a high dose) and longer LORR compared to B6. QTL analysis revealed several additive and interacting loci for various phenotypes, as well as examples of genotype interactions with sex. QTLs for different EtOH phenotypes were largely non-overlapping, suggesting separable genetic influences on these behaviors. The most compelling main-effect QTLs were for hypothermia on chromosome 16 and for LORR on chromosomes 4 and 6. Several QTLs overlapped with loci repeatedly linked to EtOH drinking in previous mouse studies. The architecture of the traits we examined was complex but clearly amenable to dissection in future studies. Using integrative genomics strategies, plausible functional and positional candidates may be found. Uncovering candidate genes associated with variation in these phenotypes in this population could ultimately shed light on genetic factors underlying sensitivity to EtOH intoxication and risk for alcoholism in humans

Analysis of experimental results of a Pressurized Solid Oxide Fuel Cell System simulating a Hybrid Power Plant

The low-carbon economy of the future needs low consumption of fossil and high quality renewable based fuels. This requires high efficiencies, good part-load performance and fuel flexibility. A very promising concept to achieve that is the combination of solid oxide fuel cells (SOFC) with a gas turbine (GT) in a pressurized hybrid power plant. However, experimental data for such SOFC/GT systems are rare. Thus, the DLR built a test rig to analyse such a system with 30 kW electrical output. A 30 kW SOFC module is used under pressurized conditions with components that emulate the GT. Commercially available stacks and state of the art peripheral components are installed. These include e.g. a hot anode off-gas recirculation blower, a steam reformer and recuperator. The system was put into operation and is used to experimentally analyse its operational behaviour. This publication will give insights about the current status of the experimental work. It will outline the basic SOFC/GT process, the implementation within the installed SOFC system and the degrees of freedom in comparison to a coupled system. Experimental results are shown and the impact of main parameters is analysed

Distal and proximal prehension is differentially affected by Parkinson's disease - the effect of conscious and subconscious load cues

Prehension movements consist of distal (grasp) and proximal (reach, lift) components. The proximal lifting movements (achieved at the wrist) of patients with Parkinson's disease (PD) are characterized by bradykinesia. With respect to the distal component, PD patients show pathologically high grip forces (generated by the fingers) and slowing of force development indicative of disturbed sensorimotor adjustments during prehension. Combining kinematic and force analyses of prehension movements, we investigated whether PD differentially affects the adjustments of the distal or proximal prehension components to current load conditions. First, PD patients (n = 12) and healthy, age-matched control subjects grasped and lifted light and heavy objects without any load cues. Then, they were presented with cues that indicated changes in object load. These load cues were either consciously perceived or rendered subconscious through use of the technique of metacontrast masking. Consistent with the functional organization of the basal ganglia, patients with PD could adapt distal prehension components (grip force) to current load conditions using both types of cues. However, they were impaired in adjusting proximal prehension components (lift velocity). While controls were able to normalize lift velocity with the help of both conscious and subconscious load cues, the PD patients could use neither form of cue, and retained a pathological overshoot in lift velocity. Our results demonstrate that visuomotor integration during prehension movements differs at distal and more proximal joints and that deficits in this integration are pronounced for the latter in Parkinson's disease

Experimental Setup of a Pressurized Solid Oxide Fuel Cell System for Hybrid Power Plants

The future energy system will favour electricity generating devices with highest efficiencies, good part load performance and fuel flexibility to consume as little chemical energy as possible. One promising concept to realize that is the combination of solid oxide fuel cells (SOFC) with a gas turbine (GT) in a hybrid power plant. By that the high efficiency and good part load performance of the fuel cell is used while remaining chemical energy in the off-gas of the fuel cell is converted in the gas turbine. Via an integrated steam reformer carbon based fuels can be used. Exhaust heat is recuperated. Recently, Mitsubishi-Hitachi Power Systems demonstrated a hybrid power plant with an electrical power output of 250 kW that runs on natural gas. It is being tested in field trials in Japan and a scale-up to 1 MW is in progress. However, since experimental data for such SOFC/GT systems are scarce the DLR is building a demonstrator with 30 kW electrical output. In the first step two separate test rigs were build. One uses a real GT and components that emulate the SOFC. This MGT system was setup by the Institute of Combustion Technology. The other one uses a 30 kW SOFC under pressurized conditions with components that emulate the GT. This SOFC system was built by the Institute of Engineering Thermodynamics and includes a hot anode off-gas recirculation, a steam reformer and recuperator. State of the art components and commercially available stacks with electrolyte supported cells (ESC) are used. Both systems were put into operation and are now being used to experimentally analyse their operational behaviour. After all necessary investigations it is planned to merge the SOFC with the GT and thereby build a real coupled SOFC/GT system. This presentation will give an overview of the underlying hybrid power plant process, the implementation within the currently installed SOFC system and its first experimental results. The basic design choices, key challenges during the development and necessary modifications will be shown. The experimental results, such as efficiency, power output, part load performance and control strategies will give an insight about the current status of the project