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Measurement of dynamic strength of concrete at impact relevant strain rates and pressures is the purpose of the described study. Therefore, an experimental design of direct planar impact experiments with longitudinal and transverse strain gauges is analyzed in predictive hydrocode simulations using an elastic-plastic damage model for concrete. The calculations and first experimental results on mortar show decreasing phase velocities of stress waves both in longitudinal and lateral gauges. The model clearly associates it with the onset of damage, possibly interpreted as a failure wave. Numerical analysis is furthermore used to compare a monolithic target block to a thoroughly assembled concrete sample in order to include flat gauges in the material. The planned experimental procedure to derive wave speeds, particle velocities and strain rates from stress measurements is anticipated and validated on the basis of simulated gauge signals. The most important finding is the prediction and first experimental confirmation that concrete ultimate strength and damaged yield stress can be derived at strain rates in the order of 10 4 /s from the proposed type of experiments. This technique promises new insight into the strength and failure processes of concrete in the challenging loading region around the characteristic minimum of its shock particle velocity relationship.

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E-selectin is an adhesion molecule of endothelial cells that binds to cancer cells mediated by sialyl Lewis A (sLea) or sialyl Lewis X (sLe(x)). It is suspected to be involved in hematogenous metastasis of tumors. Therefore, it is worth examining E-selectin expression in human colorectal cancer and its hepatic metastasis. In the present study, E-selectin was clearly revealed on the endothelial cells of small vessels adjacent to cancer nests both in primary and in metastatic nests in immunohistochemistry. In these tissues, E-selectin was observed on the endothelial cells lining the lumen of small vessels. Its expression adjacent to cancer nests appears to be induced through some stimuli by cancer cells, since its degree of expression is inversely correlated to the distance of the blood vessels from the cancer nests (p < 0.001). Endothelial cells adjacent to the metastatic lesion expressed E-selectin more extensively than those adjacent to the primary foci. This is also in line with the finding on serum E-selectin levels which were significantly elevated in the metastatic group as compared with the non-metastatic group. The serum E-selectin level may provide useful information in the diagnosis for hepatic metastasis of colorectal cancer, although the results are still tentative.