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371.
The quality of running waters is reflected in the composition of benthic diatom assemblages. The biological assessment of
changes in the composition, and thus of changes in water quality, was carried out in the lowland mid-sized Bzura River, Central
Poland, over the period of 30 years. The benthic diatom material consisted of samples collected in two investigation periods,
in 1972 and in 2003–2004. The methods applied were three diatom indices, IPS — Specific Pollution Sensitivity Index, GDI —
Genetic Diatom Index and TDI —Trophic Diatom Index, and the OMNIDIA computer program, which are commonly used in Europe. The
aim of the study was demonstrating the process of restoration that occurred in the river. The Bzura was included to the most
polluted ones in Poland till 1996. Since 1998 a gradual improvement in water quality has been observed, which is caused by
a number of biological-technical measures, mostly a proper organization of sewage management in most cites located on the
river. In 1972 the IPS classified Bzura water into Water Quality Class IV-V, while in 2003–2004 it reached much higher values,
i.e. Class III–IV. On the basis of the GDI Class III was determined in the whole river in 2003–2004, while its values indicated
Class III–IV in 1972. The trophic index, TDI attributed Bzura water to the eutrophic to hypereutrophic zone in 2003–2004,
and to one degree better water, i.e. from the mesoeutrophic to eutrophic zone, in 1972. 相似文献
372.
373.
Jonathan Diep Huong Le Kim Le Ewelina Zasadzinska Jasmine Tat Pheng Yam Ryan Zastrow Natalia Gomez Jennitte Stevens 《Biotechnology progress》2021,37(6):e3192
Cell line development (CLD) represents a critical, yet time-consuming, step in the biomanufacturing process as significant resources are devoted to the scale-up and screening of several hundreds to thousands of single-cell clones. Typically, transfected pools are fully recovered from selection and characterized for growth, productivity, and product quality to identify the best pools suitable for single-cell cloning (SCC) using limiting dilution or fluorescence-activated cell sorting (FACS). Here we report the application of the Berkeley Lights Beacon Instrument (BLI) in an early SCC process to accelerate the CLD timeline. Transfected pools were single-cell cloned when viabilities reached greater than 85% or during selection when viabilities were less than 30%. Clones isolated from these accelerated processes exhibited comparable growth, productivity, and product quality to those derived from a standard CLD process and fit into an existing manufacturing platform. With these approaches, up to a 30% reduction in the overall CLD timeline was achieved. Furthermore, early process-derived clones demonstrated equivalent long-term stability compared with standard process-derived clones over 50 population doubling levels (PDLs). Taken together, the data supported early SCC on the BLI as an attractive approach to reducing the standard CLD timeline while still identifying clones with acceptable manufacturability. 相似文献