## 3 Results and Discussions
### Time-Integrated Acquisitions at Four Conditions of the Irradiation-Sample Complex  
The results shown in Figures 5 and 6 also reveal that any material surface within the FOV of the sample chamber that received the fiber-delivered irradiation and caused multiple or reverberating reflections contributed to the luminescence measured. To acquire delayed luminescence originating specifically from the yeasts, it would be necessary to assess the luminescence of the sample chamber under conditions that would sub-compose the condition of the yeasts post-irradiation. For that purpose, the same irradiation-acquisition interleaved process of acquiring the luminescence from the sample chamber was performed at four conditions of the sample chamber in combination with the prior irradiation. These four conditions and the corresponding level of luminescence acquired as a function of the duration of the integration are given in Figure 7. Figure 7 displayed the same results in a logarithmic scale of the exposure time in (A) and in a linear scale of the exposure time in (B) to better visualize the short-time differences and the long-time patterns, respectively. The four conditions, as stated below, correspond to the four sets in either Figure 7A or 7B that are counted from the bottom-most trace in ascending order. The bottom-most trace corresponds to a baseline irradiation-acquisition interleaved acquisition with an empty chamber and at no actual irradiation. The second trace from the bottom-most one corresponds to a mock irradiation-acquisition interleaved acquisition from yeasts in the chamber but with no irradiation. The difference between this second trace and the bottom-most one was attributed to the spontaneous photon emission of the yeasts. The third trace from the bottom or the second trace from the top corresponds to the irradiation-acquisition interleaved acquisition from an empty chamber under a normal sequence of irradiation. The difference between this third trace and the bottom-most one was attributed to the afterglow of the illumination-delivery fiber. The fourth trace from the bottom of the topmost trace corresponds to the irradiation-acquisition interleaved acquisition from yeasts in the chamber under a normal sequence of irradiation. The difference between this topmost trace and the bottom-most one was attributable to the combination of delayed photon emission of the yeast, afterglow of the illumination-delivery fiber, and spontaneous photon emission. Figure 7: Delayed luminescence acquired at four different conditions of the yeast sample and irradiation. (**A**,**B**) are the same set of data presented in the logarithmic scale of the abscissa to reveal the patterns happening at times less than 1 s and times greater than 100 s. There are four traces of measurements corresponding to four sets of sample/irradiation combinations. The middle panel illustrates the differences among the four sets using the four annual shapes. The white inner area of the annular shape represents an empty sample chamber. The dense grid-like inner area of the annular shape represents yeast as the sample. The red dot at the 12 o’clock position of the annular shape represents irradiation via the fiber prior to the acquisition of the luminescence from the chamber. The data presented were the average over three sequences performed independently. Time Differentiation of the Time-Integrated Luminescence at Three Conditions of the Sample-Irradiation Setting  
The time-integrated luminescence of the three non-baseline conditions shown in Figure 7 are plotted in Figure 8A after subtracting the baseline trace, or the bottom-most trace of Figure 7. The bottom trace marked by the blue squares of the smallest size represents the integration of the spontaneous irradiance from the yeast. As the time of integration increases, this trace, starting noticeably at \(\sim\)10 s (the smaller values were cut off at the scale), increases steadily at a near-constant slope.