(+++) = 0.09-0.099, Intense (++++) = >0.1) (see Figure 2, bottom panel). The intensity of the marks per region of neurosphere was defined by the ≥60% of the cells with the above rank. Based on the rank values, Mann-Whitney U was used for nonparametric statistical analysis of ranked fluorescent intensity to address differences between two groups (progressive differentiation states - i.e. comparing differentiated core to undifferentiated neurospheres) or two regions within a neurosphere (comparing intensity of cells at the periphery to those at the core) (Table 1).
