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The Southern Corridor of bishopric district was uncovered in early 1920s as the first Romanesque remains in the 3rd Courtyard of the Prague Castle. Based on historical context it likely originates from 11th − 12th century. To benchmark this estimate, radiocarbon dating of charcoals found in its mortars was performed. The results support the previous age estimate and suggest an ongoing building activity on site such as raising cascade walls at least till 14th − 16th century. [ABSTRACT FROM AUTHOR]

Twenty-five samples of ivory artefacts were analysed using a radiocarbon dating method. These artefacts were part of a collection of 77 items seized during a wildlife law enforcement operation targeting online illegal ivory trade. Based on the opinion of a qualified expert, 14 of the 25 samples were declared antique, meaning their presumed origin is older than 1947. According to the European Union's law, antique ivory is exempt from an otherwise total ban on commercial ivory activities since such trade does not contribute to the current decline in elephant population. The radiocarbon measurement has revealed alarming findings that 17 of the 25 processed samples (68%) are not antique as their origin is younger than 1947. The antique expert's determination of the ivory age failed in 12 of 14 cases (86%). [ABSTRACT FROM AUTHOR]

Clustered DNA damage induced by 10, 20 and 30 MeV protons in pBR322 plasmid DNA was investigated. Besides determination of strand breaks, additional lesions were detected using base excision repair enzymes. The plasmid was irradiated in dry form, where indirect radiation effects were almost fully suppressed, and in water solution containing only minimal residual radical scavenger. Simultaneous irradiation of the plasmid DNA in the dry form and in the solution demonstrated the contribution of the indirect effect as prevalent. The damage composition slightly differed when comparing the results for liquid and dry samples. The obtained data were also subjected to analysis concerning different methodological approaches, particularly the influence of irradiation geometry, models used for calculation of strand break yields and interpretation of the strand breaks detected with the enzymes. It was shown that these parameters strongly affect the results. [ABSTRACT FROM AUTHOR]

Clustered DNA damages are induced by ionizing radiation, particularly of high linear energy transfer (LET). Compared to isolated DNA damage sites, their biological effects can be more severe. We investigated a clustered DNA damage induced by high LET radiation (C 290 MeV u and Fe 500 MeV u) in pBR322 plasmid DNA. The plasmid is dissolved in pure water or in aqueous solution of one of the three scavengers (coumarin-3-carboxylic acid, dimethylsulfoxide, and glycylglycine). The yield of double strand breaks (DSB) induced in the DNA plasmid-scavenger system by heavy ion radiation was found to decrease with increasing scavenging capacity due to reaction with hydroxyl radical, linearly with high correlation coefficients. The yield of non-DSB clusters was found to occur twice as much as the DSB. Their decrease with increasing scavenging capacity had lower linear correlation coefficients. This indicates that the yield of non-DSB clusters depends on more factors, which are likely connected to the chemical properties of individual scavengers. [ABSTRACT FROM AUTHOR]