Schlecht verwischte Spuren?
Hier die Studie:

https://academic.oup.com/clinchem/article/52/7/1446/5627058

Preparation of a Chimeric Armored RNA as a Versatile Calibrator for Multiple Virus Assays
Qiuying Huang, Yangjian Cheng, Qiwei Guo, Qingge Li
Clinical Chemistry, Volume 52, Issue 7, 1 July 2006, Pages 1446–1448, https://doi.org/10.1373/clinchem.2006.069971
Published: 01 July 2006

Dort findet sich folgende Abbildung:

Calibration of the real-time RT-PCR assay for HCV, HIV-1, SARS-CoV1, and SARS-CoV2.