Cortical neuronal loss and hippocampal sclerosis are not detected by voxel-based morphometry in individual epilepsy surgery patients

Voxel-based morphometry (VBM) has detected differences between brains of groups of patients with epilepsy and controls, but the sensitivity for detecting subtle pathological changes in single subjects has not been established. The aim of the study was to test the sensitivity of VBM using statistical parametric mapping (SPM5) to detect hippocampal sclerosis (HS) and cortical neuronal loss in individual patients. T1-weighted volumetric 1.5 T MR images from 13 patients with HS and laminar cortical neuronal loss were segmented, normalised and smoothed using SPM5. Both modulated and non-modulated analyses were performed. Comparisons of one control subject against the rest (n ¼ 23) were first performed to ascertain the smoothing level with the lowest number of SPM changes in controls. Each patient was then compared against the whole control group. The lowest number of SPM changes in control subjects was found at a smoothing level of 10 mm full width half maximum for modulated and non-modulated data. In the patient group, no SPM abnormalities were found in the affected temporal lobe or hippocampus at this smoothing level. At lower smoothing levels there were numerous SPM findings in controls and patients. VBM did not detect any abnormalities associated with either laminar cortical neuronal loss or HS. This may be due to normalisation and smoothing of images and low statistical power in areas with larger interindividual differences. This suggests that the methodology may currently not be suitable to detect particular occult abnormalities possibly associated with seizure onset zone in individual epilepsy patients with unremarkable standard structural MRI

Radio observation of the Gum Nebula Region

This thesis describes the results of an investigation of the physical properties of the Gum Nebula. For this investigation a radio continuum map of the region was made at 2326 MHz and resolution ⅓° with the HartRAO antenna. This map was used to generate spectral index images and an infrared to radio flux density ratio (IRR) image. The latter image shows that the IRR of the nebula is in the range 20 to 250, identifying it as an old SNR. Several spectral index images of this region were generated using two different methods, one based on the isolation of the nebula from its background radiation, the other based on TT-plots (Turtle et al., 1962). The two methods yield similar results, which show that the nebula has a thermal shell with a non-thermal region in its interior. Below the galactic plane the thermal region dominates and above the plane the nonthermal region. These results suggest a model of an old SNR with an H II region shell. Spectral line observations of hydrogen recombination lines and hydroxyl (OH) were made with the HartRAO and the Mopra telescopes. The detection of hydrogen recombination lines at four positions in the thermal regions of the nebula give electron temperatures and emission measures in the ranges 4000 to 6000 K and 220 to 460 pc.cm⁻⁶ respectively. The turbulent velocities are of the order of 20 km/s. A search for shocked OH lines at 1667 MHz and 1720 MHz in the Gum Nebula gave results that were negative, but numerous unshocked 1667 MHz OH lines were detected. The latter were used in a test for an expansion of the nebula. The most plausible fit to the data gives an expansion centre at l = 260.5°, b = -2.5° and at a distance of 0.7 kpc from us. The front face angular radius and expansion velocity are 10.5° and 16 km/s respectively. The back face angular radius and expansion velocity are 8.50 and 7 km/s respectively

Postcolonial thinking and modes of being-with others

CITATION: Woermann, M. 2020. Postcolonial thinking and modes of being-with others. Etica & Politica, XXII, 3:833-848.The original publication is available at http://www2.units.it/eticaThis paper seeks to interrogate the mode of relationality – or Being-with Others – that supports a responsible postcolonial thinking. The paper draws from both the Western and African philosophical traditions. Three modes of Being-with Others are identified at the hand of Martin Heidegger’s and Jean-Luc Nancy’s work, namely the exterior mode, in which we simply exist alongside one another; the interior mode, wherein our identities are assimilated by a historicallyconstituted community; and, the non-essentialised mode, wherein our identities are open to Others. The paper critically explores African Humanism and African Communitarian in order to demonstrate how – in practice – these views often lend support to the exterior mode and the interior mode respectively. As an alternative to these views, a reading of African philosophy that foregrounds the Political as first philosophy is given. It is demonstrated how this reading not only demands a non-essentialised mode of Being-with Others (which will be motivated as the preferred relational mode), but also leads to a view of postcoloniality that is premised on the inherent openness of being and community.Publisher's versio

Concerns and review of naturally occurring radioactive materials and their occurrence in municipal activities

Ionizing radiation from natural sources (radioactive nuclei in the earth's crust, cosmic rays) is present everywhere on Earth. Naturally occurring radionuclides, primarily in soil and rock also represent potential sources of exposure to the population. If materials containing natural radionuclides are in the unaltered form then they are described by the term NORM. Human activities such as mining and coal combustion can interfere or alter the natural state and lead to elevated concentrations of NORM. When the concentrations of naturally occurring radioactive materials are significantly increased i.e. technologically enhanced, we use the acronym TENORM. \ud NORM and TENORM occur in a variety of non-nuclear industries producing processed natural materials, such as extraction of natural gas and oil, phosphate industry, TiO2 production, mineral sands production, ceramic industry and production of building materials.\ud The theoretical section provides an overview of the radioactivity basics, biological effects of ionizing radiation, international and Slovenian legislation in NORM regulations and an overview of the problematic industries in Slovenia, where NORM may be enhanced to TENORM. The main focus is on two municipal industries: drinking water and wastewater treatment.\ud The experimental section begins with a description of measurement location selection. It then presents the measuring equipment and method used for measuring the ultrafiltration modules and sewage sludge from preselected wastewater treatment plants in Slovenia. The final part of the experimental section presents spectrometric analysis of a specific sewage sludge sample and discusses the results. Finally the proposals for reducing ionizing radiation exposure to a reasonable minimum are presented.\u

Kinematics of the Young Stellar Objects associated with the Cometary Globules in the Gum Nebula

An analysis of proper motion measurements of the Young Stellar Objects (YSOs) associated with the Cometary Globules (CGs) in the Gum Nebula is presented. While earlier studies based on the radial velocity measurements of the CGs suggested expansion of the system of the CGs, the observed proper motion of the YSOs shows no evidence for expansion. In particular the kinematics of two YSOs embedded in CGs is inconsistent with the supernova explosion of the companion of $\zeta$ Pup about 1.5 Myr ago as the cause of the expansion of the CG system. YSOs associated with the CGs share the average proper motion of the member stars of the Vela OB2 association. A few YSOs that have relatively large proper motions are found to show relatively low infrared excesses.Comment: 19 pages, 6 figures, 4 tables, Accepted for publication in MNRA

Epileptic monocular nystagmus and ictal diplopia as cortical and subcortical dysfunction

AbstractWe present the case of a patient with ictal monocular nystagmus and ictal diplopia who became seizure-free after resection of a right frontal focal cortical dysplasia (FCD), type 2B. Interictal neuroophthalmological examination showed several beats of a monocular nystagmus and a spasm of the contralateral eye. An exclusively ictal monocular epileptic nystagmus could be an argument for an exclusively cortical involvement in monocular eye movement control. The interictal findings in our patient, however, argue for an irregular ictal activation of both the cortical frontal eye field and the brainstem

Interstellar absorptions and shocked clouds towards supernova remnant RX J0852.0-4622

We present results of survey of interstellar absorptions towards supernova remnant (SNR) RX J0852.0-4622. The distribution of KI absorbers along the distance of the background stars is indicative of a local region (d<600pc) strongly depopulated by KI line-absorbing clouds. This fact is supported by the behavior of the interstellar extinction. We find four high-velocity CaII components with velocities of >100km/s towards three stars and identify them with shocked clouds of Vela SNR. We reveal and measure acceleration of two shocked clouds at the approaching and receding sides of Vela SNR along the same sight line. The clouds acceleration, velocity, and CaII column density are used to probe cloud parameters. The total hydrogen column density of both accelerating clouds is found to be similar (~6*10^{17} cm$^{-2}$) which indicates that possibly there is a significant amount of small-size clouds in the vicinity of Vela SNR.Comment: accepted in MNRA