## 2 Materials and Methods  
### Data Acquisition  
The data used to construct the models were acquired from the experiments performed at the Jerome Candy Research Institute for Advanced Biological and Technological Sciences (JCRI-ABTS) in Takoma Park, MD, USA. The CAP generation device used in this study, CHCP, has been described in our previous studies [25]. It is comprised of a high-frequency electorsurgical generator and a conversion unit. The conversion unit utilizes a high voltage transformer connected to the output from the electrosurgical generator and upconverts voltage up to 4 kV while downconverting frequency and power to less than 300 kHz and 40 W, respectively. The main reactive oxygen and nitrogen species generated by CHCP were OH (A\({}^{2}\Sigma^{+}\)-X\({}^{2}\Pi^{+}\)) at 309 nm; N\({}_{2}\) (C\({}^{3}\Pi_{u}\)-B\({}^{3}\Pi_{g}\)) second positive system (SPS) at 337 and 357 nm; N\({}_{2}\)\({}^{+}\) (B\({}^{2}\Sigma_{u}\)+\({}^{-}\)X\({}^{2}\Sigma_{g}\)+) first negative system (FNS) at 391 and 427 nm; He at 667 nm; and O\({}^{\prime}\) at 777 nm as reported in the spectrum in [23]. Human breast ductal carcinoma BT-474 and breast adenocarcinoma SK-BR-3 were purchased from ATCC (Manassas, VA, USA). Human adenocarcinoma cell lines MCF-7 and MDA-MB-231 were generously donated by Professor [PERSON]'s laboratory at Howard University. Cells were cultured in ATCC-recommended media supplemented with 10% fetal bovine serum and 1% Pen Strep (Thermo Fisher Scientific, Waltham, MA, USA) in a 37 \({}^{\circ}\)C and 5% CO\({}_{2}\) humidified incubator (Thermo Fisher Scientific, Waltham, MA, USA). When cells reached approximately 80% confluence, cells were seeded at a concentration of 10\({}^{5}\) cells/well into 12-well plates (USA Scientific, Ocala, FL, USA). Helium flow was set to a constant 3 lpm, and power was set to 80 p (equivalent to 15.7 W) or 120 p (equivalent to 28.7 W). Cells were treated directly by CHCP 24 h after being seeded, and the plasma scalpel was placed 1.5 cm away from the surface of the cell media. The data metrics, including intracellular ROS, caspase activity (CA), Ki-67 expression, G1 activity, and confluence for each cell line were acquired up to 48 h after treating all cells with CHCP for 3 and 5 min at 120 p except for the SK-BR-3 cell line, which was treated at 80 p for Ki-67 models. Data of intracellular ROS, CA, cell cycle, and proliferation were collected by IncuCyte(r) (Sartorius, Gottingen, Germany). The inputted data needed to be time-series dependent and composed of at least 48 data time points that were of the same hourly time scale. Therefore, experimental data generated by IncuCyte(r) (Sartorius, Gottingen, Germany) were proper and convenient in that IncuCyte(r) (Sartorius, Gottingen, Germany) enables imaging and continuous quantification of cell behavior over time. Protocols and data for CA, cell cycle, and confluence for the 4 breast cancer cell lines have been reported in our previous work [14]. The experimental protocol for intracellular ROS was performed as follows: prior to CHCP treatment, cells were stained for intracellular ROS with CM-H2 DCFDA (ThermoFisher Scientific, Waltham, MA, USA) at appropriate concentrations according to manufacturer's instructions, incubated under standard conditions of 37 \({}^{\circ}\)C and 5% CO\({}_{2}\) for 30 min, replenished with fresh warm media, and then incubated under the same conditions again for 30 min for recovery. After CHCP treatment at 120 p (equivalent to 28.7 W) for 3 and 5 min, intracellular ROS activity for all cell lines was monitored and quantified in the IncuCyte(r) in an incubator for 48 h under standard conditions. CHCP-generated H\({}_{2}\)O\({}_{2}\) and NO\({}_{2}\)\({}^{-}\) concentrations were measured in PBS by colorimetric kits (Sigma-Aldrich, St. Louis, MO, USA and Promega, Madison, WI, USA). Corresponding concentrations of H\({}_{2}\)O\({}_{2}\) and NO\({}_{2}\)\({}^{-}\) were added to the cells for intracellular ROS measurement as positive controls.