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Abstract. Thermal oxidation of the (0001) basal plane of highly oriented pyrolitic graphite leads to the removal of monoatomic carbon layers from the surface and to the formation of circular pits and steps on the exposed plane. Scanning tunneling microscopy and current imaging tunneling spectroscopy are used to study a localized surface state at the Fermi level on the circular edges of the pit. The surface state appears as the maximum of the local density of states at 10-50 meV below the Fermi level. The appearance of the state does not depend on the orientation of the step. The explanation for this effect includes the superposition of the two different surface states. The first one is due to the existence of an edge in the graphite sheet. The second one is due to fused disclination centers caused by mechanical deformations on the terrace. [ABSTRACT FROM AUTHOR]

Skin prick testing (SPT) in combination with the clinical history of the patient is one important step in the diagnosis of IgE-mediated occupational allergies. However, skin test performance is related to the quality of allergen extracts. The present consensus document was prepared by an EAACI Task Force consisting of an expert panel of allergologists and occupational physicians from Germany, Italy, Spain, France, Austria, and Poland. All members of the panel were also involved in the data collection within the European multicentre study STADOCA ( Standard diagnosis for occupational allergy). The aim of this Task Force was the assessment of the quality of commercially available SPT solutions for selected occupational allergens under standardized procedure conditions in different European centres and institutes of Occupational Medicine. The data evaluation shows a wide variability among SPT solutions and also indicates that the sensitivity of several SPT solutions is low. Therefore, improvement and standardization of SPT solutions for occupational allergens is highly recommended. Clinical practitioners should also not presume that their SPT solutions are fully reliable. The main objective of the document is to issue consensus suggestions for the use of SPT with occupational allergens based on the European multicentre study STADOCA, on existing scientific evidence and the expertise of a panel of allergologists. [ABSTRACT FROM AUTHOR]

Background Skin prick testing ( SPT) is an important step in the diagnosis of Ig E-mediated occupational allergic diseases. The outcome of SPT is related to the quality of allergen extracts. Thus, the aim of the study was to assess different commercially available SPT solutions for selected occupational allergens. Methods SPT was performed in 116 bakers, 47 farmers and 33 subjects exposed to natural rubber latex ( NRL), all with work-related allergic symptoms. The SPT solutions from different manufacturers ( n = 3-5) for wheat flour, rye flour, soy, cow hair/dander, storage mites ( Tyrophagus putrescentiae, Lepidoglyphus destructor, Acarus siro) and NRL were analysed with respect to their protein and antigen contents. SPT was carried out in 16 allergy centres in six European countries using standardized procedures. Specific Ig E values were used as the gold standard to calculate the sensitivity and specificity of SPT solutions. The optimal cut-point for each SPT solution was determined by Youden Index. Results Protein and antigen contents and patterns of the SPT solutions varied remarkably depending on the manufacturer. While SPT solutions for wheat flour and soy reached overall low sensitivities, sensitivities of other tested SPT solutions depended on the manufacturer. As a rule, solutions with higher protein and antigen content showed higher sensitivities and test efficiencies. Conclusions There is a wide variability of SPT solutions for occupational allergens, and the sensitivity of several solutions is low. Thus, improvement and standardization of SPT solutions for occupational allergens is essential. [ABSTRACT FROM AUTHOR]

Abstract: We have designed and built an ESN-STM spectrometer dedicated to single electron spin detection. Our spectrometer couples a home-made STM with a Real-Time Spectrum Analyzer. The head of the spectrometer allows routine imaging of molecules deposited on surfaces with high tunnelling current set point. In order to provide a maximal ESN-STM signal power transfer from the source (i.e. tunnelling junction) to the amplifier stage we have developed an impedance matching circuit between the tunnelling junction and impedance of RF signal amplifier. Our impedance matching circuit is based on application of a wide-spectrum amplifier equipped with FET transistor. In order to validate the usefulness of our ESN-STM spectrometer tests of sensitivity are presented. The main advantage of our spectrometer is the fact that it allows the collection of spin spectra from every single point of the topography image. [ABSTRACT FROM AUTHOR]