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The presented work shows the methodological problems of mortar radiocarbon dating. Dating of lime mortars is based on setting the present 14C concentration of atmospheric CO2 by mortar carbonates in the hardening process. The big difficulty is the presence of aggregate, especially carbonatious one. The application of limestone fragments as aggregate in mortar, is connected with the presence of carbon partially or completely devoid of the radioactive isotope 14C. To carry out radiocarbon dating of the mortars reliably, it was necessary to remove the limestone aggregates. In this context, the application of petrographic studies that enable determination of mineral composition and the percentage of aggregate turns out to be particularly important. Such an identification allows to reconstruct mortar technology and, in combination with geological studies on the investigated terrain, helps to identify the provenance of the applied raw material. To make possible the comparison of the analysed mortar results and the verification of the applied methods, in year 2001 control mortars (mortars with established age) were used. The analyses were performed on mortars from a Romanesque castle built in the years 1177-1230 AD (Wleń, SW part of Poland) and from roman buildings with an approximate age of 140BC-68 AD (west coast of the Dead Sea,). We present the complex study of the mortar including both petrographical analyses and radiocarbon dating. The gas proportional counting technique (GPC) was applied for radiocarbon dating. Thin sections of roman mortars showed the carbonatious character of the binder and a large part of the aggregate; this was the source of the apparent age in radiocarbon dating. In spite of efforts to eliminate the lime aggregate from the mortar (by freezing, warming up, and separating under the binocular), and taking into consideration the amount of old carbon admixture derived from the carbon stable isotopes composition, there is still a great disproportion between historical and radiocarbon dating of these mortars. The results of the 14C dating show, that improvement of the binderaggregate separation process is necessary. The mortar aggregate from the Polish castle samples does not contain limestone grits, only scarce quartz grains. These Romanesque mortars were tested successfully and the existing architectural and historical data confirm the results obtained by GPC. [ABSTRACT FROM AUTHOR]

The article presents the case study of a family suffering with late infantile amaurotic idiocy. With the exception of the most frequent infantile form, which occurs mainly in Jewish children, other types of this disease do not show any racial predilection. The first symptoms of the Jansky-Bielschowsky type are failure of psycho-motor development, convulsions, speech disorders and frequently cerebellar symptoms in the form of ataxia or myoclony. The cerebrospinal fluid aminotransferases examination made simultaneously with the last examination of these enzymes in serum showed CSF SGOT, 80 u., CSF SGPT, 58 u. The course of the disease was characteristic for late infantile amaurotic family idiocy.