Accelerator mass spectrometry measurement of the reaction 35Cl(n,γ)36Cl at keV energies

The nuclide 35Cl can act as a minor “neutron poison” in the stellar slow neutron capture process

Electrodiagnostic subtyping in Guillain–Barré syndrome patients in the International Guillain–Barré Outcome Study

Background and purpose: Various electrodiagnostic criteria have been developed in Guillain–Barré syndrome (GBS). Their performance in a broad representation of GBS patients has not been evaluated. Motor conduction data from the International GBS Outcome Study (IGOS) cohort were used to compare two widely used criterion sets and relate these to diagnostic amyotrophic lateral sclerosis criteria. Methods: From the first 1500 patients in IGOS, nerve conduction studies from 1137 (75.8%) were available for the current study. These patients were classified according to nerve conduction studies criteria proposed by Hadden and Rajabally. Results: Of the 1137 studies, 68.3% (N = 777) were classified identically according to criteria by Hadden and Rajabally: 111 (9.8%) axonal, 366 (32.2%) demyelinating, 195 (17.2%) equivocal, 35 (3.1%) inexcitable and 70 (6.2%) normal. Thus, 360 studies (31.7%) were classified differently. The areas of differences were as follows: 155 studies (13.6%) classified as demyelinating by Hadden and axonal by Rajabally; 122 studies (10.7%) classified as demyelinating by Hadden and equivocal by Rajabally; and 75 studies (6.6%) classified as equivocal by Hadden and axonal by Rajabally. Due to more strictly defined cutoffs fewer patients fulfilled demyelinating criteria by Rajabally than by Hadden, making more patients eligible for axonal or equivocal classification by Rajabally. In 234 (68.6%) axonal studies by Rajabally the revised El Escorial (amyotrophic lateral sclerosis) criteria were fulfilled; in axonal cases by Hadden this was 1.8%. Conclusions and discussion: This study shows that electrodiagnosis in GBS is dependent on the criterion set utilized, both of which are based on expert opinion. Reappraisal of electrodiagnostic subtyping in GBS is warranted

Optimisation and Analysis of a Circularly Polarised Organic Light Emitting Diode (CP-OLED)

Because of their excellent properties and low energy requirement, organic light emitting diodes (OLEDs) are commonly used in display applications. Improvements and new concepts are widely studied, scientifically as well as commercially. This advancement has brought forward novel, innovative technologies like bendable or transparent displays, as well as increased efficiency and stability of established devices. Nevertheless, due to their amorphous nature, regular OLEDs only emit unpolarised light. In this thesis, the development of a highly functional circularly polarised OLED (CP-OLED) is pursued, characterised by both, excellent device performance and large circular polarisation (CP) effects. To quantify these effects, a measurement set-up for circularly polarised electroluminescence (CP-EL) is assembled, and different ways to evaluate and present this data are developed. For best expressiveness and comparability, the g value at the wavelength of the EL spectrum maximum (g@maxEL) is reported here. As chosen CP-OLED systems, devices from three categories are analysed: 1. I-CPL emitters 2. one component systems 3. mixed systems With the exception of intrinsic CPL approaches, all systems require thermal annealing to produce a chiral liquid crystalline phase, which is responsible for later CPL emission. For this, ideal curing conditions are developed for each system. All materials were evaluated in thin film as well as in OLED devices. Firstly, two helicene based molecules, H1-Me2 and ThiahelalkBZT, are utilized as potential intrinsic CPL emitters. As expected from calculations and similar materials in literature, no measurable CP-effect is found. Additionally, both molecules are tested as chiral inducers within an F8BT matrix. As such, they achieve g@maxEL values of up to 0.42 and 0.41, respectively. Secondly, multiple chirally functionalised polyfluorenes (PFs) are analysed as one component CP-OLED systems. Both, homo- and co-polymers are compared. To minimize complexity, CP-OLEDs are also built in a cavity system, thereby reducing the number of emission peaks. The disruptive influence of keto-defects within the chirally functionalised polymer is explained. Based on the position of the chiral centre, an odd-even effect resulting in opposite handedness for circular dichroism (CD) and gEL curves is found. Over all, g@maxEL values of up to -0.55 are measured with chiral side chain functionalised PFs. Thirdly, an F8BT based mixed CPL system is analysed in depth. The opposite CP-effect of both chiral inducer enantiomers, R5011 and S5011, is demonstrated. As was done for all polymer based systems, ideal curing conditions to achieve maximum CP-effects are developed. Supported by DSC measurements, required curing times and temperatures increase with increasing molecular weight of the polymer. Best CD and gEL values are found for a Mw of 7 - 21 kg/mol. The result of thickness variations of different layers within this stack are explained and strategies to reduce cathode reflections leading to optical interference are proposed. The influence of the chiral inducer concentration is analysed. It is demonstrated that using different enantiomeric excess (e.e.) ratios of both chiral inducer enantiomers with a constant combined chiral inducer concentration produces more comparable results than changing the chiral inducer concentration directly. CP-effects of a specific effective chiral inducer enantiomer concentration are equivalent to the same chiral inducer concentration with only one enantiomer used. Over all, g@maxEL values of up to -1.12 are found with F8BT + R5011 mixed systems

Data set of: Die motorische Entwicklung von Kindern mit frühkindlichem Innenschielen.

Data sets of: Die motorische Entwicklung von Kindern mit frühkindlichem Innenschielen. Klinische Monatsblätter für Augenheilkunde

New test of modulated electron capture decay of hydrogen-like ¹⁴²Pm ions: Precision measurement of purely exponential decay

An experiment addressing electron capture (EC) decay of hydrogen-like 142Pm60+ions has been conducted at the experimental storage ring (ESR) at GSI. The decay appears to be purely exponential and no modulations were observed. Decay times for about 9000 individual EC decays have been measured by applying the single-ion decay spectroscopy method. Both visually and automatically analysed data can be described by a single exponential decay with decay constants of 0.0126(7)s−1 for automatic analysis and 0.0141(7)s−1 for manual analysis. If a modulation superimposed on the exponential decay curve is assumed, the best fit gives a modulation amplitude of merely 0.019(15), which is compatible with zero and by 4.9 standard deviations smaller than in the original observation which had an amplitude of 0.23(4)