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Abstract. Four different Fourier transform infrared spectroscopic techniques (near infrared diffuse reflection (NIR/DR), mid-infrared attenuated total reflection (mIR/ATR) using two different instruments and mid-infrared transmission (mIR/Tr) spectroscopy) in combination with multivariate chemometrics were investigated for their potential for discriminating Emmental cheese of various geographic origins. A total of 20 Emmental cheese samples produced in winter from Switzerland (n=6), Allgäu (Germany) (n=3), Bretagne (France) (n=3), Savoie (France) (n=3), Vorarlberg (Austria) (n=3) and Finland (n=2) were analysed. The normalised spectra or their 2nd derivatives were analysed by principal component analysis (PCA) and linear discriminant analysis (LDA) of the PCA-scores. Despite the few samples in this preliminary investigation clear trends were observed. The mIR transmission spectra achieved 100% correct classification in LDA when differentiating the Swiss Emmental from the other samples pooled as one group. The NIR/DR spectroscopy allowed a classification by the six regions of cheese origin.

Four Swiss Emmental cheeses from four different factories were analysed with an "electronic nose"based on a mass spectrometer detector, the SMart Nose$^{{\rm TM}}$. Three sampling methods, i.e. non-preconcentrated static headspace, Purge-and-Trap and solid phase microextraction (SPME), were compared in order to discriminate the cheese ripening ages. The use of a preconcentration technique was found to be helpful for this application due to the possibility to extract volatile compounds with higher molecular masses. From the two systems tested, the SPME was considered from far the best method because of its better repeatability, its simplicity and its compatibility with an autosampler.

Summary: Surface energy fluxes were measured in the Dischma-valley near Davos, Switzerland at 1970 m from August 6th to August 15th, 1980. They are part of a case study for the microscale atmospheric conditions of an alpine valley. The universal function phiv H could be derived from the whole set of profile measurements of temperature, humidity and wind speed. It corresponds to the relation which was found over homogeneous terrain.

The problem of polar and subpolar inversions is attacked. Thus a literature review of the exploration of the polar lower atmosphere is presented together with an attempt to classify these inversions, according to the participating processes, such as subsidence, advection and radiation. These physical processes are incorporated into a simple inversion model, giving the heights of inversion and cloud base, the radiative cooling rates and the vertical profiles of the thermodynamic quantities and the turbulent fluxes. The model is applied to a period with subsidence inversion over the Norwegian Sea during summer. The case study shows a good agreement between the results of the steady-state model and the mean observed thermodynamic structure of the atmospheric boundary layer.

Summary The development of a cold front influenced by orography and large scale forcing is examined with a two-dimensional meso-scale model. The model is based on the primitive equations and uses the hydrostatic and anelastic approximations. Gradients of the basic flow and temperature field in the third dimension are taken into account during the simulations. Low diffusive numerical schemes and radiation boundary conditions reduce the numerical errors to an acceptable minimum for a two day simulation and avoid reflections at the upper and lateral boundaries. Frontogenetical forcing is included in the simulations by specifying either a vertically sheared or horizontally convergent basic zonal flow field. Model runs with an idealized cold front were carried out over flat terrain and in the presence of a bell shaped mountain ridge.

A model of rejection and regeneration of peripheral nerve allografts in rats is presented. A 2.5-cm segment of 28 right sciatic nerves was transplantated orthotopically from LEW.1W to DA and from DA to LEW.1W. With a microsurgical technique, proximal and distal coaptations were performed. In an autologous control group the same surgical procedure was applied. Evaluation included clinical estimation of motor recovery and macroscopic appearance of the graft, electrophysiological examination, conventional histology, and immunohistology. The latter concentrated on demonstration of monomorphic and polymorphic determinants of MHC class I and II antigens and of macrophages. By functional, electrophysiological, and histological parameters it was demonstrated that after rejection a certain degree of regeneration took place in the allografts. Both rejection and subsequent regeneration were studied in detail by immunohistology. During the course of Wallerian degeneration MHC class I expression on myelin sheaths could be demonstrated. When the rejection response occurred, additional MHC class II expression on myelin sheaths and on vascular endothelia was observed. Recipient specific class I–positive macrophages were infiltrating the graft from the epineurium and the coaptation sites, and were later present at the sites of myelin degradation. At 6 weeks postoperatively donor-specific MHC products were no longer detectable, but recipient-specific Schwann cells were present in the allograft tissue.

In 183 clinical isolates ofStaphylococcus aureus, toxic shock syndrome toxin was detected in 13.7 %, enterotoxin A in 20.2 %, enterotoxin B in 7.7 %, enterotoxin C in 5.5 % and enterotoxin D in 3.3 %. Seventy-three (39.9 %) of the strains were found to produce one or more toxins. Multiple secretion of toxins was rare (<1 % of all strains) except for the combinations enterotoxin A with toxic shock syndrome toxin and enterotoxin A with enterotoxin D. These combinations were observed at significantly higher frequencies (4.9 % and 2.2 %, respectively) than would have been expected from values calculated from respective individual frequencies (0.88 % and 0.06 %) (p<0.0001). In comparison withStaphylococcus aureus strains isolated from miscellaneous material,Staphylococcus aureus blood culture isolates produced enterotoxin D in significantly larger amounts and at higher frequencies (p=0.01 in both cases). These toxins might play an important pathogenic role inStaphylococcus aureus infections.

The experimental studies show different stages of regeneration and degeneration in autologous and allogenic nerve grafts in 187 rats with and without immunosuppression with Cyclosporin A. Allografts were used in related rats only differing in the major histocompatibility complex (MHC) with the same non-MHC background.

Zusammenfassung Es wird über eine Reihenuntersuchung auf Syphilis in einem Durchgangslager berichtet. Die Untersuchung betraf 22740 Menschen und erstreckte sich auf einen Zeitraum von 3 Jahren. Mittels der genau geschilderten