Datenschutz bei Lernsoftware

Der Wandel in Kommunikation und Informationsbeschaffung hat auch vor Schulen nicht halt gemacht. Das Lernen mit modernen Medien ist inzwischen notwendiger Bestandteil jeder Schulausbildung geworden. Der folgende Beitrag gibt einen überblick über die M?glichkeiten der Nutzung von Lernsoftware im Internet und zeigt die damit verbundenen datenschutzrechtlichen Probleme auf.     

Photodegradation of DMMP and CEES on zirconium doped titania nanoparticles

The structure and photocatalytic activity of Zr doped TiO₂ nanocrystallites with a varying Zr content between 0 and 15 wt% prepared by an efficient and environmentally benign method has been studied by vibrational spectroscopy, TEM and XRD. It is shown that the presence of Zr⁴⁺ ions stabilizes the anatase structure and delays phase transformation to rutile upon annealing as well as retarding grain coarsening. All TiO₂ samples up to 13 wt% Zr doping concentration show better or similar photoreactivity compared to P25 (Degussa) for decomposition of adsorbed 2-chloroethyl ethyl sulphide (CEES) and dimethyl methylphosphonate (DMMP) in synthetic air at room temperature. The most efficient sample for photodegradation of both CEES and DMMP is shown to be titania doped with 6.8 wt% Zr. The photodegradation of CEES is faster than DMMP under the same experimental conditions. On the undoped TiO₂ sample urea residues are detected spectroscopically. Much less is detected on the Zr doped samples. Mode resolved in situ FTIR surface spectroscopy enables distinction of CEES or DMMP, decomposition products as well as the influence of residues from the particle synthesis. This facilitates extraction of intra-comparable reaction rates. Possible explanations for the improved reactivity of the Zr doped titania are discussed.     

Incidence of primary malignancies other than breast cancer among women treated with radiation therapy for benign breast disease

In addition to left ventricular pump failure and low cardiac output, structural and metabolic alterations of skeletal muscle are thought to contribute to exercise intolerance seen in patients with CHF. Studies using cardiac myocytes have implicated nitric oxide elaborated by inducible nitric oxide synthase (iNOS) as a potential agent associated with the genesis of dilated cardiomyopathy. The present study was designed to locate iNOS in the working skeletal muscle of patients with congestive heart failure. Specific antibodies were used to detect iNOS by immunohistochemistry in skeletal muscle biopsies (m. vastus lateralis) of 37 patients with left ventricular pump failure and 8 normal controls. The expression was restricted to skeletal muscle myocytes and was increased five- to ninefold in patients with chronic heart failure. There was no statistically significant difference in iNOS expression between patients with dilated cardiomyopathy and those with ischemic cardiomyopathy. The finding of a locally increased expression of iNOS and the experimental evidence that NO attenuates the contractile performance of the skeletal muscle suggest that the expression of iNOS may be responsible for the exercise intolerance seen in patients with chronic heart failure.     

Evaluation of on-line flue gas measurements by MISiCFET and metal-oxide sensors in boilers

Metal insulator silicon carbide field-effect transistor sensors, metal-oxide sensors, and a linear Lambda sensor in an electronic nose was used to measure on-line in hot flue gases from a boiler. Flue gas from a 100-MW pellets-fuelled boiler has been used to feed the experimental setup. Several reference instruments, which measure the flue gases in parallel to the sensor array, are connected to the electronic nose. Data was collected during six weeks and then evaluated. Using principal component analysis as the data evaluation method, different operating modes for the boiler have been identified in the data set. The different modes could be described in terms of high or low O/sub 2/ and CO concentration. Furthermore, we have shown that it seems possible to use a sensor array to determine the operating mode of the boiler and, by partial least-squares models, measure the CO concentration when the boiler operates in its optimum mode.     

An integrated model of residential and employment location in a metropolitan region

The purpose of this paper is to improve the tools available for analyzing and evaluating land-use and transport policies in a regional planning context. A normative residential location submodel is combined with a predictive submodel for the location of employment. The demand side of the residential location submodel is formulated as a nested multinomial logit model of the joint choice of residential location and transportation mode. The cost of commuting is assumed to be a major determinant of locational choice. The employment location submodel is based on the assumption that accessibility to the labor force is the strategic location factor. Two versions of the submodels are proposed corresponding to a post- and pre-distribution modal split in the familiar four-step transport model. Policy tests of a newly proposed, large-scale traffic investment program in the Stockholm region are reported.An earlier version of this paper was presented at the 30th European Congress, Istanbul, August 1990.