## 3 Discussion
It allows membrane bound spherical core-shell charge separated bodies (from 28-100 nm diameters) to exhibit dipolar coupling with incident electric fields [32] in the range of 12-45 GHz of the electromagnetic spectrum with an inverse relation between frequency and size dimensions. Such phenomena which occur at resonant frequencies determined by the structural dimensions and charge status can lead to rupture events [33], resulting in leakage of matrix contents depending on the exposure power conditions and duration of treatment. Cells are composed of multiple subcellular organelles bound by membranes, which maintain distinct environments within the matrix separated from the cytoplasm outside. Peroxisomes and microbodies are a class of cell organelles, which function as a source of reactive oxygen species (ROS). ROS causes oxidative stress and DNA damage at high levels inhibiting cell division [34]. Generally observed to be spherical in shape, peroxisomes resemble the membrane bound core-shell charge separated structures described above [32], raising the possibility that 85-105 GHz MMW irradiation may have resulted in peroxisome rupture with subsequent ROS leakage leading to inhibited cell division. However, as per published measurementsand understanding, dipolar coupling at 85-105 GHz frequencies will correspond to charge separated spherical membrane bound structures of diameters around 11-14 nm [32]; which are much below the peroxisomes size range of 200-500 nm [35, 36, 37], indicating that reduced cell division upon 85-105 GHz exposure is not accountable to ROS mediated mechanisms. However, other smaller vesicles with resonant dimensions covered by this bandwidth may contribute to the observed non-thermal effects by different non-ROS mediated pathways. Such processes could explain the ambiguous MMW treatment results reported from other studies [12, 13, 14] described above in the introduction. As such, the apoptosis-promoting effects MMW radiation on several types of tumors could also be a potential reason for the observed effects. Sweeping frequency regimes over 75-105 GHz at 0.2 mW/cm\({}^{2}\) resulted in apoptosis of H1299 lung cancer cells [5]. Experimentally, irradiation at 35 GHz is reported to activate the apoptosis in A375 melanoma cells in vitro [38]. The transient receptor potential vanilloid 1 (TRPV1) expression is altered in prostate, colon, bladder, pancreas and breast cancers. TRPV1 forms high conductivity channels in the cell membrane, and its prolonged activation could lead to cell apoptosis. Pre-treatment with capsaicin, TRPV1 agonist and subsequent exposure to 60 GHz radiation at 100 mW for 20 min facilitates apoptosis in Triple Negative Breast Cancer Cell Lines [39]. The combined action of TRPV1 agonist and MMW radiation demonstrates robust sensitization to cell death even at low concentrations of the chemical agonist. Our experiments have showed complete termination of the cells' growth at 17.17 mW/cm\({}^{2}\); possibly via strong apoptotic effect by using the higher power densities that was required for better penetration since yeast cells bear thick cell walls which were absent in the H1299 and A375 cells described above. However, further experiments are requisite to exclude intracellular thermal effects or responses of the cells when using an open-ended waveguide. We intend to investigate the complete range of effects of the W-band (85-105 GHz) MMW irradiation to unravel the mechanism(s) of action by using deleted yeast library collections of over 5100 single gene deletions. In summary, our experiments examined the effects of MMW (85-105 GHz) on _Saccharomyces cerevisiae_ yeast and demonstrated, that W-band (85-105 GHz) MMW irradiation at a power density of ~1.0 mW/cm\({}^{2}\) for 5-6 h exposure duration results in a 62% reduction in the growth rate of irradiated yeast cells at a density of 50 cells/\(\mu\)L. MMW radiation effects were found to be frequency, energy dose and cell density dependent.