Excess wing in glass-forming glycerol and LiCl-glycerol mixtures detected by neutron scattering.

The relaxational dynamics in glass-forming glycerol and glycerol mixed with LiCl is investigated using different neutron scattering techniques. The performed neutron spin echo experiments, which extend up to relatively long relaxation time scales of the order of 10 ns, should allow for the detection of contributions from the so-called excess wing. This phenomenon, whose microscopic origin is controversially discussed, arises in a variety of glass formers and, until now, was almost exclusively investigated by dielectric spectroscopy and light scattering. Here we show that the relaxational process causing the excess wing can also be detected by neutron scattering, which directly couples to density fluctuations.

Polymer enrichment decelerates surfactant membranes near interfaces.

Close to a planar surface, lamellar structures are imposed upon otherwise bulk bicontinuous microemulsions. Thermally induced membrane undulations are modified by the presence of the rigid interface. While it has been shown that a pure membrane's dynamics are accelerated close to the interface, we observed nearly unchanged relaxation rates for membranes spiked with large amphiphilic diblock copolymers. An increase of the polymer concentration by a factor of 2-3 for the first and second surfactant membrane layers was observed. We interpret the reduced relaxation times as the result of an interplay between the bending rigidity and the characteristic distance of the first surfactant membrane to the rigid interface, which causes the hydrodynamic and steric interface effects described in Seifert's theory. The influence of these effects on decorated membranes yields a reduction of the frequencies and an amplification of the amplitudes of long-wavelength undulations, which are in accordance to our experimental findings.

[Differences in the measurement results of Goldmann applanation tonometry with and without fluorescein]. / Unterschiede in den Messergebnissen nach Goldmann-Applanationstonometrie mit und ohne Fluoreszein.

BACKGROUND: Goldmann applanation tonometry (GAT) is still the gold standard for measuring the intraocular pressure (IOP). Usually fluorescein eye drops are used additional to topical anesthesia to gain the best visualization results. The present study evaluated the differences in the results of GAT with and without fluorescein. METHODS: A total of 400 eyes of 200 patients without known glaucoma were enrolled in this study and randomized to two groups: group A (first measurement without, second measurement with fluorescein) and group B (first measurement with fluorescein, second without). All measurements were performed by the same examiner with the same slit lamp. Results were analyzed by Bland-Altman plots and Spearman's correlation test. RESULTS: The examined groups showed no significant differences regarding patient age, astigmatism or reason for consulting. In both groups performing GAT without the application of fluorescein led to significantly lower measurement results. The differences were 1.5 ± 1.7 mmHg SD in group A, 1.2 ± 1.6 mmHg SD in group B and 1.4 ± 1.65 mmHg SD for all eyes. The intraocular pressure (IOP) and the differences between the groups were independent of patient age, astigmatism, reason of consulting or IOP level. Both groups showed outliers up to 10 mmHg difference because of corneal edema. CONCLUSIONS: Measurements from GAT without fluorescein differed significantly from measurements with fluorescein, independently of patient age, astigmatism, reason for consulting or IOP level. The mean difference of 1.4 mmHg may seem negligible in daily routine but can lead to serious consequences in borderline cases.

[Invasive squamous cell carcinoma of the conjunctiva]. / Invasives Plattenepithelkarzinom der Bindehaut.

We report the case of a 71-year-old male who was first diagnosed with conjunctival squamous cell carcinoma in September 2010. The lesion was excised twice and cryotherapy of the margins was performed. On histology the margins were not tumor-free but this was not followed up by further excision. After 5 months the patient was referred to this department with a growing tumor mass which had infiltrated into the anterior chamber and partly destroyed the iris. Because of this advanced finding extended enucleation was performed. The histological examination showed a well differentiated squamous cell carcinoma and no evidence of metastasis in lymph nodes or elsewhere could be found by conventional computed tomography (CT) and positron emission CT (PET-CT).

[Unilateral retinal pseudoarteritis after eyeball contusion]. / Unilaterale retinale pseudoarteritis nach contusio bulbi.

This article reports an unusual case of unilateral frosted branch angiitis. Three major groups of this disease are known: secondary frosted branch angiitis due to viral infection or autoimmune diseases, frosted branch-like angiitis related to malignant diseases and the rare entity of idiopathic frosted branch angiitis. A 58-year-old patient presented with strictly unilateral sheathing and partly occluded retinal arteries, vitritis and macular edema and 4 months prior to presentation he suffered a contusion of the eye with traumatic cataract and vitreous hemorrhage followed by cataract extraction and vitrectomy. The general medical history revealed that the contralateral eye and biochemical analyses were unremarkable despite slightly elevated antinuclear antibody (ANA) levels. Under high dose steroid therapy the patient showed slow improvement in all clinical findings. This case does not fit into any of the known groups and can therefore be defined as pseudoarteritis.