[...] cells were removed to a cover glass and treated with plasma for 2 min, then returned to TS broth and centrifuged for 10 min. Cells were harvested and washed twice with PBS, then mixed with tryptic soy agar. The agar block was fixed with 2·5% glutaraldehyde in 0·1 mol l−1 PBS. Samples were postfixed in 1% (w/v) OsO4 in 0·1 mol l−1 PBS for 2 h at room temperature, washed once with the same buffer, dehydrated in a graded ethanol series and embedded in low‐viscosity medium. Thin sections of the specimens were double‐stained with uranyl acetate and lead citrate...
What does mean this bolded point? Is it a decimal separator, or has other scientific meaning?
If this is decimal point, why is vertically middle aligned?
Source: a recent Korea researchers team article