University of Antwerp

About: University of Antwerp is a education organization based out in Antwerp, Belgium. It is known for research contribution in the topics: Population & Large Hadron Collider. The organization has 16682 authors who have published 48837 publications receiving 1689748 citations. The organization is also known as: Universiteit Antwerpen & UAntwerp.

Splitting of CO2 by vibrational excitation in non-equilibrium plasmas: a reaction kinetics model

Abstract: We present a zero-dimensional kinetic model of CO2 splitting in non-equilibrium plasmas. The model includes a description of the CO2 vibrational kinetics (25 vibrational levels up to the dissociation limit of the molecule), taking into account state-specific VT and VV relaxation reactions and the effect of vibrational excitation on other chemical reactions. The model is applied to study the reaction kinetics of CO2 splitting in an atmospheric-pressure dielectric barrier discharge (DBD) and in a moderate-pressure microwave discharge. The model results are in qualitative agreement with published experimental works. We show that the CO2 conversion and its energy efficiency are very different in these two types of discharges, which reflects the important dissociation mechanisms involved. In the microwave discharge, excitation of the vibrational levels promotes efficient dissociation when the specific energy input is higher than a critical value (2.0 eV/molecule under the conditions examined). The calculated energy efficiency of the process has a maximum of 23%. In the DBD, vibrationally excited levels do not contribute significantly to the dissociation of CO2 and the calculated energy efficiency of the process is much lower (5%).

Diffusion MRI fiber tractography of the brain

Abstract: The ability of fiber tractography to delineate non-invasively the white matter fiber pathways of the brain raises possibilities for clinical applications and offers enormous potential for neuroscience In the last decade, fiber tracking has become the method of choice to investigate quantitative MRI parameters in specific bundles of white matter For neurosurgeons, it is quickly becoming an invaluable tool for the planning of surgery, allowing for visualization and localization of important white matter pathways before and even during surgery Fiber tracking has also claimed a central role in the field of “connectomics,” a technique that builds and studies comprehensive maps of the complex network of connections within the brain, and to which significant resources have been allocated worldwide Despite its unique abilities and exciting applications, fiber tracking is not without controversy, in particular when it comes to its interpretation As neuroscientists are eager to study the brain's connectivity, the quantification of tractography-derived “connection strengths” between distant brain regions is becoming increasingly popular However, this practice is often frowned upon by fiber-tracking experts In light of this controversy, this paper provides an overview of the key concepts of tractography, the technical considerations at play, and the different types of tractography algorithm, as well as the common misconceptions and mistakes that surround them We also highlight the ongoing challenges related to fiber tracking While recent methodological developments have vastly increased the biological accuracy of fiber tractograms, one should be aware that, even with state-of-the-art techniques, many issues that severely bias the resulting structural “connectomes” remain unresolved

Axonal neuropathy with optic atrophy is caused by mutations in mitofusin 2.

Abstract: Objective Charcot-Marie-Tooth (CMT) neuropathy with visual impairment due to optic atrophy has been designated as hereditary motor and sensory neuropathy type VI (HMSN VI). Reports of affected families have indicated autosomal dominant and recessive forms, but the genetic cause of this disease has remained elusive. Methods Here, we describe six HMSN VI families with a subacute onset of optic atrophy and subsequent slow recovery of visual acuity in 60% of the patients. Detailed clinical and genetic studies were performed. Results In each pedigree, we identified a unique mutation in the gene mitofusin 2 (MFN2). In three families, the MFN2 mutation occurred de novo; in two families the mutation was subsequently transmitted from father to son indicating autosomal dominant inheritance. Interpretation MFN2 is a mitochondrial membrane protein that was recently reported to cause axonal CMT type 2A. It is intriguing that MFN2 shows functional overlap with optic atrophy 1 (OPA1), the protein underlying the most common form of autosomal dominant optic atrophy, and mitochondrial encoded oxidative phosphorylation components as seen in Leber's hereditary optic atrophy. We conclude that autosomal dominant HMSN VI is caused by mutations in MFN2, emphasizing the important role of mitochondrial function for both optic atrophies and peripheral neuropathies. Ann Neurol 2006;59:276–281