Development of crystal optics for X-ray multi-projection imaging for synchrotron and XFEL sources.

X-ray multi-projection imaging (XMPI) is an emerging experimental technique for the acquisition of rotation-free, time-resolved, volumetric information on stochastic processes. The technique is developed for high-brilliance light-source facilities, aiming to address known limitations of state-of-the-art imaging methods in the acquisition of 4D sample information, linked to their need for sample rotation. XMPI relies on a beam-splitting scheme, that illuminates a sample from multiple, angularly spaced viewpoints, and employs fast, indirect, X-ray imaging detectors for the collection of the data.

Long-lived electron emission reveals localized plasmon modes in disordered nanosponge antennas.

We report long-lived, highly spatially localized plasmon states on the surface of nanoporous gold nanoparticles-nanosponges-with high excitation efficiency. It is well known that disorder on the nanometer scale, particularly in two-dimensional systems, can lead to plasmon localization and large field enhancements, which can, in turn, be used to enhance nonlinear optical effects and to study and exploit quantum optical processes. Here, we introduce promising, three-dimensional model systems for light capture and plasmon localization as gold nanosponges that are formed by the dewetting of gold/silver bilayers and dealloying.

Suppression of Radiative Damping and Enhancement of Second Harmonic Generation in Bull's Eye Nanoresonators.

We report a drastic increase of the damping time of plasmonic eigenmodes in resonant bull's eye (BE) nanoresonators to more than 35 fs. This is achieved by tailoring the groove depth of the resonator and by coupling the confined plasmonic field in the aperture to an extended resonator mode such that spatial coherence is preserved over distances of more than 10 μm. Experimentally, this is demonstrated by probing the plasmon dynamics at the field level using broadband spectral interferometry.

Toward plasmonics with nanometer precision: nonlinear optics of helium-ion milled gold nanoantennas.

Plasmonic nanoantennas are versatile tools for coherently controlling and directing light on the nanoscale. For these antennas, current fabrication techniques such as electron beam lithography (EBL) or focused ion beam (FIB) milling with Ga(+)-ions routinely achieve feature sizes in the 10 nm range. However, they suffer increasingly from inherent limitations when a precision of single nanometers down to atomic length scales is required, where exciting quantum mechanical effects are expected to affect the nanoantenna optics.

Strong field acceleration and steering of ultrafast electron pulses from a sharp metallic nanotip.

We report a strong, laser-field induced modification of the propagation direction of ultrashort electron pulses emitted from nanometer-sized gold tapers. Angle-resolved kinetic energy spectra of electrons emitted from such tips are recorded using ultrafast near-infrared light pulses of variable wavelength and intensity for excitation. For sufficiently long wavelengths, we observe a pronounced strong-field acceleration of electrons within the field gradient at the taper apex.

Probing the Ca(2+) switch of the neuronal Ca(2+) sensor GCAP2 by time-resolved fluorescence spectroscopy.

We report fluorescence lifetime and rotational anisotropy measurements of the fluorescent dye Alexa647 attached to the guanylate cyclase-activating protein 2 (GCAP2), an intracellular myristoylated calcium sensor protein operating in photoreceptor cells. By linking the dye to different protein regions critical for monitoring calcium-induced conformational changes, we could measure fluorescence lifetimes and rotational correlation times as a function of myristoylation, calcium, and position of the attached dye, while GCAP2 was still able to regulate guanylate cyclase in a Ca(2+)-sensitive manner. We observe distinct site-specific variations in the fluorescence dynamics when externally changing the protein conformation.

Enantioselective Synthesis of Diamino Dicarboxylic Acids.

The preparation of alkyl diamino dicarboxylic acids with high optical purity (100% ee, >98.5% de) and high yields based on asymmetric catalytic hydrogenation is described. The required prochiral precursors are prepared from dialdehydes and Z-, Boc-, and acetyl-protected phosphonoglycines.

Large-scale synthesis of hematoregulatory nonapeptide SK&F 107647 by fragment coupling.

Linear and convergent routes for the large-scale preparation of the hematoregulatory nonapeptide (Glp-Glu-Asp)2-DAS-(Lys)2 (2, SK&F 107647) were investigated. A convergent approach ('3 + 2'-route employing Boc-and benzyl ester protecting groups) was selected for the preparation of multihundred-gram quantities of 2. Key steps were the preparation and the coupling of tripeptide hydrochloride (HCl.

[Carpal tunnel syndrome. Causes, symptoms, therapy].

358 cases with operated carpal tunnel syndrome are reported. The operation is indicated if the clinical symptomatology is obvious and/or the electromyographical (EMG) examination is pathological. Using microsurgery and the operating laser (267 operations) for the cut ligamentum up to 76,2% of all cases were asymptomatic after the operation.

Exacerbation of brain abscess during exclusive treatment with steroids, demonstrated by computerised tomography.

A case of acute brain abscess in a 59-year-old man is presented. The primary CT findings were misinterpreted as a brain infarct or possibly a tumour. Under steroid therapy an activation of the brain abscess was observed in only nine days and in spite of an immediate operation the patient died.

[Thrombotic aneurysm as the cause of a cerebral seizure--operation and cure (case report)].

Report on a 27 years old male patient, who was operated and cured of a "tumor" parieto-occipital, 1.5 cm in diameter, found in computerized tomography. The histological examination showed a thrombosed aneurysm.

[Brain injuries in skiers].

During the last skiing season (November 1981 to March 1982), 33 patients were treated for craniocerebral injuries caused by skiing accidents. Based on the classification made by Tönnis und Loew, 11 patients had grade I, 11 patients grade II and 11 patients grade III (including 3 open craniocerebral injuries). Four patients underwent operation for intracranial hematoma.

[Carpal tunnel syndrome as an unrecognized disease in the aged].

Although the symptoms are very characteristical (in our patients 91,5% pain, 69,2% disturbed sensibility and 29,2% weakness) and the neurological diagnosis is typical (82,9% disturbed sensibility, 30,6% weakness, 57,1% atrophy of the thenar muscle) faults in diagnosis are possible. Particularly in old age it is mistaken for vertebral or vascular diseases. If conservative treatment is ineffective or the compression of the nerve is enlarging fast, surgical treatment will be indicated.