News Article | February 15, 2017
-- Largest imaging study of ADHD to date identifies differences in five regions of the brain, with greatest differences seen in children rather than adults. Attention-deficit hyperactivity disorder (ADHD) is associated with the delayed development of five brain regions and should be considered a brain disorder, according to a study published in The Lancet Psychiatry. The study is the largest to look at the brain volumes of people with ADHD, involving more than 3200 people. The authors say the findings could help improve understanding of the disorder, and might be important in challenging beliefs that ADHD is a label for difficult children or the result of poor parenting. ADHD symptoms include inattention and/or hyperactivity and acting impulsively. The disorder affects more than one in 20 (5.3%) under-18 year olds, and two-thirds of those diagnosed continue to experience symptoms as adults. Previous studies have linked differences in brain volume with the disorder, but small sample sizes mean results have been inconclusive. Areas thought to be involved in ADHD are located in the basal ganglia - a part of the brain that controls emotion, voluntary movement and cognition - and research has previously found that the caudate and putamen regions within the ganglia are smaller in people with ADHD. The new international study measured differences in the brain structure of 1713 people with a diagnosis of ADHD and 1529 people without, all aged between four and 63 years old. All 3242 people had an MRI scan to measure their overall brain volume, and the size of seven regions of the brain that were thought to be linked to ADHD - the pallidum, thalamus, caudate nucleus, putamen, nucleus accumbens, amygdala and hippocampus. The researchers also noted whether those with ADHD had ever taken psychostimulant medication, for example Ritalin. The study found that overall brain volume and five of the regional volumes were smaller in people with ADHD - the caudate nucleus, putamen, nucleus accumbens, amygdala and hippocampus. "These differences are very small - in the range of a few percent - so the unprecedented size of our study was crucial to help identify these. Similar differences in brain volume are also seen in other psychiatric disorders, especially major depressive disorder." said lead author Dr Martine Hoogman, Radboud University Medical Center, Nijmegen, The Netherlands.  The differences observed were most prominent in the brains of children with ADHD, but less obvious in adults with the disorder. Based on this, the researchers propose that ADHD is a disorder of the brain, and suggest that delays in the development of several brain regions are characteristic of ADHD. Besides the caudate nucleus and putamen, for which previous studies have already shown links to ADHD, researchers were able to conclusively link the amygdala, nucleus accumbens and hippocampus to ADHD. The researchers hypothesise that the amygdala is associated with ADHD through its role in regulating emotion, and the nucleus accumbens may be associated with the motivation and emotional problems in ADHD via its role in reward processing. The hippocampus' role in the disorder might act through its involvement in motivation and emotion. At the time of their MRI scan, 455 people with ADHD were receiving psychostimulant medication, and looking back further, 637 had had the medication in their lifetime. The different volumes of the five brain regions involved in ADHD were present whether or not people had taken medication, suggesting the differences in brain volumes are not a result of psychostimulants. "The results from our study confirm that people with ADHD have differences in their brain structure and therefore suggest that ADHD is a disorder of the brain," added Dr Hoogman. "We hope that this will help to reduce stigma that ADHD is 'just a label' for difficult children or caused by poor parenting. This is definitely not the case, and we hope that this work will contribute to a better understanding of the disorder."  While the study included large numbers of people of all ages, its design means that it cannot determine how ADHD develops throughout life. Therefore, longitudinal studies tracking people with ADHD from childhood to adulthood to see how the brain differences change over time will be an important next step in the research. Writing in a linked Comment Dr Jonathan Posner, Columbia University, USA, said: "[This] is the largest study of its kind and well powered to detect small effect sizes. Large sample sizes are particularly important in the study of ADHD because of the heterogeneity of the disorder both in the biological cause and clinical manifestation... This study represents an important contribution to the field by providing robust evidence to support the notion of ADHD as a brain disorder with substantial effects on the volumes of subcortical nuclei. Future meta-analyses and mega-analyses will need to investigate medication effects as well as the developmental course of volumetric differences in this disorder." The study was funded by the National Institutes of Health. The study is part of the ENIGMA Consortium, where researchers are also studying the structure of the brain in other psychiatric disorders, allowing researchers to define differences and similarities between the disorders. It was conducted by scientists from Radboud University Medical Center, Donders Institute for Brain, Cognition and Behaviour, University of Southern California, University of Groningen, QIMR Berghofer Medical Research Institute, University Medical Center Utrecht, National Human Genome Research Institute, Asociación para la Innovación en Análisis, Gestión y Procesamiento de Datos Científicos y Tecnológicos, University Hospital Aachen, JARA Translational Brain Medicine, Research Center Juelich, Harvard Medical School, The Broad Institute, University of Bergen, Cincinnati Children's Hospital Medical Center, University of California, UC San Diego, University of Tübingen, University of Würzburg, University of Dublin, NYU Langone Medical Center, King's College London, Heidelberg University, Federal University of Rio de Janeiro, University of Zurich, Child Mind Institute, Nathan Kline Institute for Psychiatric Research, Otto-von-Guericke-University, Maastricht University, University Hospital Frankfurt, Haukeland University Hospital, Child and Adolescent Mental Health Center, Beth Israel Deaconess Medical Center, Karakter Child and Adolescent Psychiatry, VU University Amsterdam, Universitat Autònoma de Barcelona, Fundació IMIM, Hospital Universitari Vall d'Hebron, SUNY Upstate Medical University, National Institute of Mental Health.  Quote direct from author and cannot be found in the text of the Article. IF YOU WISH TO PROVIDE A LINK FOR YOUR READERS, PLEASE USE THE FOLLOWING, WHICH WILL GO LIVE AT THE TIME THE EMBARGO LIFTS: http://www.thelancet.com/journals/lanpsy/article/PIIS2215-0366(17)30049-4/fulltext
Olschewski F.,University of Wuppertal |
Ebersoldt A.,Karlsruhe Institute of Technology |
Friedl-Vallon F.,Karlsruhe Institute of Technology |
Gutschwager B.,Physikalisch - Technische Bundesanstalt |
And 9 more authors.
Atmospheric Measurement Techniques | Year: 2013
The Gimballed Limb Observer for Radiance Imaging of the Atmosphere (GLORIA) is a prototype of an imaging Fourier Transform Spectrometer (FTS) for PREMIER, a former candidate mission for ESA's Earth Explorer 7. GLORIA is deployed on board various research aircraft such as the Russian M55 Geophysica or the German HALO. The instrument provides detailed infrared images of the Upper Troposphere/Lower Stratosphere (UTLS) region, which plays a crucial role in the climate system. GLORIA uses a two-dimensional detector array for infrared limb observations in emission and therefore needs large-area blackbody radiation sources (126 mm × 126 mm) for calibration. In order to meet the highly demanding uncertainty requirements for the scientific objectives of the GLORIA missions and due to the sophisticated tomographic evaluation scheme, the spatial distribution of the radiance temperature of the blackbody calibration sources has to be determined with an uncertainty of about 0.1 K. Since GLORIA is exposed to the hostile environment of the UTLS with mutable low temperature and pressure, an in-flight calibration system has to be carefully designed to cope with those adverse circumstances. The GLORIA in-flight calibration system consists of two identical weight-optimised high-precision blackbody radiation sources, which are independently stabilised at two different temperatures. The two point calibration is in the range of the observed atmospheric infrared radiance emissions with 10 K below and 30 K above ambient temperature, respectively. Thermo-Electric Coolers are used to control the temperature of the blackbody radiation sources offering the advantage of avoiding cryogens and mechanical coolers. The design and performance of the GLORIA in-flight calibration system is presented. The blackbody calibration sources have been comprehensively characterised for their spatially (full aperture) and spectrally (7 to 13 μm) resolved radiation properties in terms of radiance temperatures traceable to the International Temperature Scale (ITS-90) at the Physikalisch-Technische Bundesanstalt (PTB), the national metrology institute of Germany.©Author(s) 2013.
Brzozowska K.,Research Center Juelich GmbH |
Pinkawa M.,RWTH Aachen |
Eble M.J.,RWTH Aachen |
Muller W.-U.,University of Duisburg - Essen |
And 4 more authors.
International Journal of Radiation Biology | Year: 2012
Background: A high cellular radiosensitivity may be connected with a risk for development of severe side effects after radiotherapy and indicate cancer susceptibility. Hence, a fast and robust in vitro test is desirable to identify radiosensitive individuals. Materials and methods: The study included 25 prostate cancer patients with severe side effects (S) and 25 patients without severe side effects (0) after radiotherapy as well as 23 male healthy age-matched donors. Blood samples were exposed to 0.5 Gy or 1 Gy of γ-rays. The initial level of double-strand breaks (dsb) and repair kinetics measured by phosphorylation of histone H2A (γ-H2AX-assay), apoptosis (Annexin V-assay) and the induction of chromatid aberrations after irradiation in the G2-phase of the cell cycle (G2-assay) were analysed. Results: A significant higher chromatid aberration yield was found in lymphocytes from prostate cancer patients when compared to healthy donors. We found no significant differences between patients S and patients 0. Conclusions: There is no obvious correlation between clinical and cellular radiosensitivity in lymphocytes of prostate cancer patients when all chosen in vitro assays are considered. Although 25% of the patients showed both severe side effects and increased radiation-induced chromosomal sensitivity, predictive value of G2-assay is doubtful. © 2012 Informa UK, Ltd.
Roeske S.,German Center for Neurodegenerative Diseases |
Roeske S.,University of Bonn |
Filla I.,University of Bonn |
Heim S.,Research Center Juelich GmbH |
And 10 more authors.
Movement Disorders | Year: 2013
Background: Although it is well established that there is cognitive dysfunction in spinocerebellar ataxia type 3 (SCA3), it is unknown whether cognition deteriorates with disease progression. We therefore prospectively studied cognitive function in patients with SCA3. Methods: Eleven patients with SCA3 were assessed using an extensive neuropsychological test battery and retested after 3.5±0.4 years. Results: In addition to ataxia and motor control, verbal learning and verbal and figural memory deteriorated significantly during the follow-up period. An increase in depressive symptoms was not observed. Conclusions: The observation that memory and learning abilities deteriorated with disease progression suggests that cognitive dysfunction is an integral part of SCA3. Because the applied tests for memory function did not require motor responses, cognitive decline cannot be attributed to progressive cerebellar ataxia. The deterioration of verbal and figural memory can be explained either by extracerebellar pathology or by disruption of cerebellar-cerebral circuitries.© 2013 International Parkinson and Movement Disorder Society.
Zhao W.,CAS Institute of Vertebrate Paleontology and Paleoanthropology |
Wang N.,CAS Institute of Vertebrate Paleontology and Paleoanthropology |
Zhu M.,CAS Institute of Vertebrate Paleontology and Paleoanthropology |
Mann U.,Research Center Juelich GmbH |
And 2 more authors.
Acta Geologica Sinica | Year: 2011
Carbon isotope (δ13Corg) analyses of non-marine clastic rocks and neritic carbonates and black shales spanning the Silurian/Devonian transition are compared from two richly fossiliferous sequences in Qujing of East Yunnan and Zoige of Sichuan, South China. The two sections, Xishancun and Putonggou sections in South China, reveal positive (δ13Corg) shifts happening in the Upper Pridoli and Lower Devonian and reaching peak values as heavy as -25.2%c (Xishancun) and -19.9%c (Putonggou) in the lowermost Lochkovian following the first occurrence of the thelodont Parathelodus and the conodont Icriodus woschmidti woschmidti (only in Putonggou Section and together with Protathyris-Lanceomyonia brachiopod fauna). These results replicate a globally known positive shift in (δ13Corg) from the uppermost Silurian to the lowermost Devonian. The (δ13Corg) variations across the Silurian/Devonian Boundary (SDB) at the two sections in South China exhibit a shift in carbon isotopic composition similar to the detailed SDB curves from the borehole Klonk-1 drilled at top of the Klonk Global Standard Stratotype-Section and Point (GSSP) in the Prague Basin, Czech Republic.addition, four microvertebrate assemblages, including the Liaojiaoshan, Xishancun, Yanglugou and Xiaputonggou assemblages, are recognized from the Silurian/Devonian transition exposed in the Xishancun and Putonggou sections, respectively. The results from both carbon isotope stratigraphy and microvertebrate assemblage sequences suggest that the SDB in South China is located at the base of the Xishancun Formation (between sample QX-20 and sample QX-21) in the Xishancun Section and the lower part of the Xiaputonggou Formation (between sample ZP-09 and sample ZP-10) in the Putonggou Section. The isotopic trend for organic carbon together with the changes of microvertebrate remains across the SDB can offer an approach to a potential correlation of the SDB from different sedimentary faciès, which help to correlate the marine with non-marine deposits.
Dueck M.,Research Center Juelich GmbH |
Schloesser M.,Research Center Juelich GmbH |
Kaparaki M.,Research Center Juelich GmbH |
Srivastava S.,Research Center Juelich GmbH |
And 2 more authors.
Proceedings of the SICE Annual Conference | Year: 2014
The total drag of transport systems such as airplanes, ships and/or trains is primarily determined by friction drag. At high Reynolds numbers (< 104) transversal surface waves are a promising approach for active drag reduction. For the application in airplanes or ships a large scale distributed real-time actuator and sensor network is required in order to provide a connection between a global flow control and the distributed actuators and sensors. For the development of this network we established a network model based on Simulink and TrueTime. To determine the network- and transmission-parameters for the model we set up a Raspberry Pi based testbed as a physical representation of a first small scale model. Using this testbed the parameters for the TrueTime network model have been retrieved. With this approach we assure a link between the large scale model and the later microcontroller based real time actuator and sensor network for distributed active turbulent flow control. © 2014 SICE.
Haussler D.,University of Kiel |
Houben L.,Research Center Juelich GmbH |
Essig S.,Fraunhofer Institute for Solar Energy Systems |
Kurttepeli M.,University of Kiel |
And 3 more authors.
Ultramicroscopy | Year: 2013
Aberration-corrected scanning transmission electron microscopy (STEM) and electron energy loss spectroscopy (EELS) investigations have been applied to investigate the structure and composition fluctuations near interfaces in wafer-bonded multi-junction solar cells. Multi-junction solar cells are of particular interest since efficiencies well above 40% have been obtained for concentrator solar cells which are based on III-V compound semiconductors. In this methodologically oriented investigation, we explore the potential of combining aberration-corrected high-angle annular dark-field STEM imaging (HAADF-STEM) with spectroscopic techniques, such as EELS and energy-dispersive X-ray spectroscopy (EDXS), and with high-resolution transmission electron microscopy (HR-TEM), in order to analyze the effects of fast atom beam (FAB) and ion beam bombardment (IB) activation treatments on the structure and composition of bonding interfaces of wafer-bonded solar cells on Si substrates. Investigations using STEM/EELS are able to measure quantitatively and with high precision the widths and the fluctuations in element distributions within amorphous interface layers of nanometer extensions, including those of light elements. Such measurements allow the control of the activation treatments and thus support assessing electrical conductivity phenomena connected with impurity and dopant distributions near interfaces for optimized performance of the solar cells. © 2013 Elsevier B.V.
Pinkawa M.,RWTH Aachen |
Brzozowska K.,Research Center Juelich GmbH |
Kriehuber R.,Research Center Juelich GmbH |
Eble M.J.,RWTH Aachen |
Schmitz S.,Research Center Juelich GmbH
Future Oncology | Year: 2016
Aim: To identify predictive assays for radiation-induced toxicity in prostate cancer patients. Patients & methods: Patients have been surveyed prospectively before and up to 16 months after radiotherapy using a validated questionnaire. Subgroups of 25 patients with minor and larger score changes, respectively, were selected for γ-H2AX, G2 and Annexin V assays. Results: A significantly higher spontaneous chromatid aberration yield (HR: 1.46 [95% CI: 1.02-2.09]; p = 0.04), higher levels of early apoptotic (HR: 1.12 [95% CI: 1.01-1.24]; p = 0.04) and late apoptotic and necrotic (HR: 1.10 [95% CI: 0.99-1.23]; p = 0.08) lymphocytes 24 h post-irradiation were found in patients with a bowel bother score decrease greater than 20 points more than 1 year after treatment. Conclusion: Chromatid aberration and apoptosis/necrosis assays appear to be suitable for the prediction of radiation-induced toxicity. © 2016 Future Medicine Ltd.
Shirpour M.,Max Planck Institute for Solid State Research |
Shirpour M.,Lawrence Berkeley National Laboratory |
Gregori G.,Max Planck Institute for Solid State Research |
Houben L.,Research Center Juelich GmbH |
And 2 more authors.
Solid State Ionics | Year: 2014
Recent studies have demonstrated that a higher dopant concentration in the grain boundary region (which includes boundary core and neighboring layers) of acceptor-doped oxides results in a remarkable decrease of grain boundary electrical resistance. In the present work, the spatial distribution of cations in the proton conducting scandium doped barium zirconate is investigated by transmission electron microscopy with high lateral resolution. Cation profiles with a resolution of 0.5 nm obtained using electron energy-loss spectroscopy indicate segregation of a noticeable part of scandium into the grain boundary core. This direct observation is consistent with the measured grain boundary electrical behavior and is interpreted in terms of the space charge model. © 2013 Elsevier B.V. All rights reserved.
PubMed | Research Center Juelich GmbH and RWTH Aachen
Type: Journal Article | Journal: Future oncology (London, England) | Year: 2016
To identify predictive assays for radiation-induced toxicity in prostate cancer patients.Patients have been surveyed prospectively before and up to 16 months after radiotherapy using a validated questionnaire. Subgroups of 25 patients with minor and larger score changes, respectively, were selected for -H2AX, G2 and Annexin V assays.A significantly higher spontaneous chromatid aberration yield (HR: 1.46 [95% CI: 1.02-2.09]; p = 0.04), higher levels of early apoptotic (HR: 1.12 [95% CI: 1.01-1.24]; p = 0.04) and late apoptotic and necrotic (HR: 1.10 [95% CI: 0.99-1.23]; p = 0.08) lymphocytes 24 h post-irradiation were found in patients with a bowel bother score decrease greater than 20 points more than 1 year after treatment.Chromatid aberration and apoptosis/necrosis assays appear to be suitable for the prediction of radiation-induced toxicity.