A new approach to the reduction of "Carte du Ciel" plates

A new procedure for the reduction of "Carte du Ciel" plates is presented. A typical "Carte du Ciel" plate corresponding to the Bordeaux zone has been taken as an example. It shows triple exposures for each object and the modelling of the data has been performed by means of a non-linear least squares fitting of the sum of three bivariate Gaussian distributions. A number of solutions for the problems present in this kind of plates (optical aberrations, adjacency photographic effects, presence of grid lines, emulsion saturation) have been investigated. An internal accuracy of 0.1'' in x and y was obtained for the position of each of the individual exposures. The external reduction to a catalogue led to results with an accuracy of 0.16'' in x and 0.13'' in y for the mean position of the three exposures. A photometric calibration has also been performed and magnitudes were determined with an accuracy of 0.09 mags.Comment: 10 pages, 12 enclosed post-script figures, uses l-aa.sty (included). Accepted for publication in Astronomy and Astrophysics Supp. Serie

Autoimmune encephalitis: Epidemiology, pathophysiology and clinical spectrum (part 2)

Autoimmune encephalitis (AE) represents a growing number of severe autoimmune-inflammatory diseases affecting both the white and grey matter of the brain. In part 1 of this series we focused on the epidemiology, pathophysiology and clinical presentation of this condition, with two illustrative cases. In this part, we will introduce the clinical criteria for AE, particularly for the diagnosis of anti-N-methyl-D-aspartate (NMDA) receptor encephalitis, which were developed to facilitate immune treatment in suspected cases before antibody results are available. We subsequently discuss the work up, differential diagnosis and treatment options for patients with this disease.

Severe neuropathy due to inhalant abuse in adolescents from Pretoria

Inhalation of volatile agents, or solvent abuse, is a dangerous pastime practised by many young adolescents in various parts of the world. Benzine, a distillate of petroleum, is a cheap and readily available solvent that is often inhaled or “sniffed” to produce a short-lived feeling of euphoria or disorientation. The aim of this report is to describe four adolescents with severe polyneuropathies secondary to chronic benzine inhalation who were seen at the Steve Biko Academic Hospital in Pretoria’s Neurology Department. Methods and patients: Four adolescent boys aged 15–18 years presented to the Department of Neurology from 2011 to 2013 with progressive weakness and muscle atrophy. Results: On examination all patients showed signs of a severe motor and sensory neuropathy. Two were wheelchair bound at the time of presentation and an initial diagnosis of Guillain-Barré syndrome was considered. Cerebrospinal fluid analysis was normal and electromyography showed severe mixed motor and sensory mainly axonal polyneuropathies in all patients. All investigations for causes of neuropathies were normal, but all patients eventually admitted that they had been abusing benzine by inhaling it for a period of at least six months. The inhalation occurred as a group activity, involving many children. Conclusion: Inhalant abuse appears to be a common practice amongst adolescents from Pretoria. It can lead to a catastrophic polyneuropathy, which should be considered in the differential diagnosis of a young patient presenting with a Guillain-Barré syndrome-type of clinical picture. Awareness amongst schools and drug programmes should be raised to prevent this tragic and highly disabling condition.http://medpharm.tandfonline.com/loi/ojfp20am201

Composite Materials with Combined Electronic and Ionic Properties

In this work, we develop a new type of composite material that combines both electrocatalytic and ionic properties, by doping a silver metal catalyst with an anion-conducting ionomer at the molecular level. We show that ionomer entrapment into the silver metallic structure is possible, imparting unique properties to the catalytic character of the metallic silver. The novel composite material is tested as the cathode electrode of fuel cells, showing significant improvement in cell performance as compared with the undoped counterpart. This new type of material may then replace the current design of electrodes in advanced fuel cells or other electrochemical devices. The possibility to merge different properties into one composite material by molecular entrapment in metals can open the way to new materials, leading to unexplored fields and applications

Absolute proper motions for the calibration of the HIPPARCOS proper motion system

Absolute proper motions of 48 Hipparcos stars in nine fields distributed over the northern hemisphere are presented. The proper motions have been recently used as part of the Bonn program for the extragalactic link of the Hipparcos proper motion system. We describe methods which have led to the absolute proper motions of the major part of the Bonn fields for the link. For six fields the extragalactic calibration was achieved using the bright quasar in the centre of the field. In addition, data of three fields of globular clusters were included. For these fields the link to an extragalactic reference system was performed by stars, whose absolute proper motions with respect to galaxies were determined on plates of the Lick astrograph. In addition, we used for the link in one field plates from the ESO Schmidt telescope in combination with measurements from glass copies of the Palomar Sky Survey. The accuracy of a single proper motion is of the order of 2 to 3 mas/a for each coordinate

Das Hardwarekonzept zur Datenerfassung der PDS 2020 GM"p"l"u"s Mikrodensitometer des Astronomischen Instituts Muenster

Available from TIB Hannover: RR 8798(1997,2) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEBundesministerium fuer Bildung, Wissenschaft, Forschung und Technologie, Bonn (Germany)DEGerman

Neurological manifestations of late onset efavirenz toxicity: a cross-sectional study of 41 patients form Pretoria, South Africa

https://drive.google.com/file/d/12qJKGjKzl95mFi9sNlWOXHRAEmCmEHMO/view?usp=sharinghttps://drive.google.com/drive/folders/1fsC_NpSTXuvTzLt0jIkHprfzdDkBJWbz?usp=sharinghttps://drive.google.com/drive/folders/10wT-Ex5avbkGINXfJ1TdD_FbVrLE5MMb?usp=sharin

Absolute Proper And Space Motions Of Globular Clusters

Absolute proper motions of ten globular clusters with respect to the Hipparcos system are presented. Our new data led to orbits in the Milky Way with smaller apogalactic distances. They are therefore in better agreement with the actual distribution of the globular clusters in the Milky Way. The kinematics of our clusters with respect to the metallicity is discussed. Key words: reference stars; kinematics of globular clusters. 1. INTRODUCTION Globular clusters are important tracers of the chemical evolution and dynamics of the Milky Way. Of special interest are the kinematics of globular clusters, which, however, require accurate absolute proper motions of these objects. We have started a program for the determination of space motions of globular clusters (e.g. Geffert 1987, Brosche et al. 1991) using plates of our refractor in combination with extragalactic calibrated proper motions of stars determined on plates of the Lick astrograph. Several other groups were also active in the deter..