Im Jahr 2000 wurden geschätzte 50 Millionen Menschen als blind entsprechend der Definition der Weltgesundheitsorganisation eingestuft. Die meisten Blinden leben in den Entwicklungsländern Asiens und Afrikas. Besonders infolge der längeren Lebenserwartung wird mit einer deutlichen Zunahme der Blinden gerechnet. Nur durch globale gezielte Programme zur Vermeidung von Blindheit können diese hohen Zahlen gesenkt werden.
Beim Glaucoma capsulare sind höhere Druckwerte und Druckschwankungen, schwierigere medikamentöse Einstellung und daraus resultierend eine rasche Abnahme neuronalen Gewebes bekannt („großer Papillentöter“). Um einen möglichst tiefen Augendruck zu erreichen, wurde Mitomycin primär als Adjuvans bei fistulierender Operation angewendet. In Erwägung gezogen werden müssen die bekannt höheren Risken wie Hypotonie mit Makulopathie und Kataraktentwicklung, Sickerkissenperforation oder Spät-Endophthalmitis.
Das „passport foldable lens placement system“ ist ein neuartiges System zur Implantation faltbarer Silikonlinsen in den Kapselsack, wobei die im Verhältnis zu bisherigen Faltlinsen-Implantationssystemen neuerlich reduzierten Außendurchmesser des Injektors gewährleisten, die Linse bei einer Inzision von 2,65 mm Breite in den Kapselsack zu implantieren und die Operation ohne Nahtverschluß zu beenden.
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The Two‐Axis Diffractometer at HASYLAB was used to measure a(sin 2 ψ ) curves by reflecting synchrotron radiation from five different lattice planes of a cold rolled nickel sheet. We are especially interested in the complex surface state of the specimen and investigated the sample as delivered without further polishing and etching. Strongly non‐linear a(sin 2 ψ ) curves were observed. Most of them vary in a non‐linear way if external uniaxial stress is applied. In this paper we study the influence of texture using formalism based on the ODF, and evaluated for the Reuss and the Voigt cases, respectively. Texture alone, however, is not sufficient to explain the whole variety of the observed effects.
Absolute single and double ionization cross sections of neon 2s- and 2p-subshells for proton (40–900 keV) and electron impact (0.2–10 keV) have been measured using photon spectroscopy in the spectral range of the vacuum ultraviolet. Cross sections for double ionization decrease more rapidly with increasing impact energy than cross sections for single ionization. No definite asymptotic energy dependence of a Bethe-Fano-plot could be found for double ionization in contrast to single ionization. The experimental results are compared with theoretical predictions of the shake-off model and Gryzinski's classical binary encounter theory. Better agreement is found with the latter, indicating that successive binary collisions have to be considered as a strong mechanism for double ionization by protons or electrons of the investigated energy range. Comparison is made with other experimental results for double ionization by photon impact or capture ionization by proton impact.
A study is presented, in which we consider the influence of cascade effects on the polarization of light emission produced in electronic or atomic collisions. Cascade transitions are shown to cause a polarization transfer which may result in a total falsification and even in a sign reversal of the polarization. Closed expressions are derived for some special cases. A practical application is given in which the derived formulas are used to understand a serious discrepancy between theoretical predictions and experimental data in the case of the line polarization due to some 3p-3s transitions in neon induced by proton impact.
The excitation of all ten levels of the neon 2p53p configuration by proton impact (100 keV-1 MeV) has been investigated by the spectral analysis of photon emission.
