ABSTRACT
This study presents the results of systematic wastewater monitoring of SARS-CoV-2 RNA and basic wastewater parameters from four different wastewater treatment plants (WWTPs) in the Czech Republic over the 2020-2022 epidemic. Two-step reverse-transcription quantitative PCR targeting genes encoding the N and Nsp12 proteins was employed to detect SARS-CoV-2 RNA loading in 420 wastewater samples. The results obtained were used to evaluate the potential of wastewater analysis for describing the epidemiological situation in cities of different sizes and determining temporal differences based on the prevailing SARS-CoV-2 variant. Strong correlations between the number of active and hospitalised COVID-19 cases in each WWTP catchment area and the concentration of SARS-CoV-2 RNA detected in the wastewater clearly demonstrated the suitability of this wastewater-based epidemiological approach for WWTPs of different sizes and characteristics, despite differences in SARS-CoV-2 variant waves, with some WWTPs showing high predictive potential. This study demonstrated on the data from the Czech Republic that targeted systematic monitoring of wastewater provides sufficiently robust data for surveillance of viral loads in sample populations, and thus contributes to preventing the spread of infection and subsequent introduction of appropriate measures.
ABSTRACT
Elephants are on the verge of extinction due to extensive poaching to obtain ivory and illegal income. According to international law, the trade in ivory of African elephants is outlawed, with a few exceptions, as for example in European Union for antique ivory obtained before 1947. There is basically only one physical method for determining the age of ivory and that is radiocarbon dating. The method uses artificially temporarily enhanced 14C content in the atmosphere to date relevant samples with high resolution. Since this advantage is slowly fading, the question arises of how to fill in the loss of the resolution. One possibility is exploiting the chronology of ivory. This work studies a whole elephant tusk and uses radiocarbon dating of samples obtained longitudinally and transversely from along the tusk to analyse the growth rate.
Subject(s)
Elephants , Radiometric Dating , Animals , Commerce , Conservation of Natural Resources , CrimeABSTRACT
Organic inclusions in lime binders provide useful samples for radiocarbon dating of historical objects. Two Czech castles Týrov and Pysolec from Late Middle Ages were explored, and tens of charcoals were found in their walls. The radiocarbon content of the charcoals was measured with accelerator mass spectrometry. The dating results showed that none of the charcoals were younger than the known historical ages (Týrov: 1260 - 1270, Pysolec: 1300 - 1340), but some were considerably older. Two charcoals from Pysolec castle dated to Palaeolithic, likely originating from fluvial sediments added as an aggregate to the mortar. When excluding these two charcoals, the others indicated most likely dates being 50-100 y older than the building dates of the castles. This systemic effect corresponds to the age of wood used for lime burning and shall be accounted for when dating mortars using charcoals.
