The natural killer (NK) T-lymphocyte population consists of two subsets utilizing a diverse and restricted Tcell receptor (TCR) repertoire, respectively. Both populations have been shown to include autoreactive cells. NKT cells carrying restricted Va14(AV14S1)Ja281/Vb8.2(BV8S2A1) TCR have been shown to recognize a-galactosylceramide (aGalCer) presented in the context of murine CD1d. In this study we screened a set of murine CD1d-autoreactive T-cell hybridomas with diverse TCR for their reactivity with several glycosylated variants of ceramide, including aGalCer. These hybridomas showed a different pattern of reactivity to CD1d-expressing antigen-presenting cells (APC) and were not reactive with any of the tested variants of ceramide. A second set of hybridomas had been selected for expression of Va14 and Vb8.2 TCR chains. These cells responded to aGalCer presented on CD1d, but were only weakly reactive to syngeneic splenocytes or CD1d-transfected cells. Their ®ne speci®city in the response to glycosylation variants of ceramide demonstrated a homogenous reactivity pattern, including reactivity to a-galactosylsphingosine, the variant of aGalCer with truncated fatty acyl chain. These ®ndings underline the differences in ligand speci®city between the two subsets of CD1d-restricted NKT cells, and demonstrate a similarity in reactivity among the hybridomas using the Va14-Ja281/Vb8.2 TCR.

The study raises the issues concerning the automatic system designed for the monitoring of movement of controlled points, located on the roof covering of the Forest Opera in Sopot. It presents the calculation algorithm proposed by authors. It takes into account the specific design and location of the test object. High forest stand makes it difficult to use distant reference points. Hence the reference points used to study the stability of the measuring position are located on the ground elements of the sixmeter-deep concrete foundations, from which the steel arches are derived to support the roof covering (membrane) of the Forest Opera. The tacheometer used in the measurements is located in the glass body placed on a special platform attached to the steel arcs. Measurements of horizontal directions, vertical angles and distances can be additionally subject to errors caused by the laser beam penetration through the glass. Dynamic changes of weather conditions, including the temperature and pressure also have a significant impact on the value of measurement errors, and thus the accuracy of the final determinations represented by the relevant covariance matrices. The estimated coordinates of the reference points, controlled points and tacheometer along with the corresponding covariance matrices obtained from the calculations in the various epochs are used to determine the significance of acquired movements. In case of the stability of reference points, the algorithm assumes the ability to study changes in the position of tacheometer in time, on the basis of measurements performed on these points.

No abstract

No abstract

The article discusses the issue of hydrostatic leveling. Its application is presented in structural health monitoring systems in order to determine vertical displacements of controlled points. Moreover, the article includes a complete computation scheme that utilizes the estimation from observation differences, allowing the elimination of the influence of individual sensors’ systematic errors. The authors suggest two concepts of processing the measurement results depending on the sensors’ connection method. Additionally, the second concept is extended by the elements allowing the prediction of the displacements by means of Kalman filtering.