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Zhuang, et al.
           yield stress, viscoelasticity, and shape fidelity from using   cells are likely to provide deeper insights into the stage-
           various type I collagen-based bio-inks [190] . By separating   dependent,  patient-specific  tumor  cell  behavior,  further
           the  class  variables  into  shape  fidelity  and  extrusion,   elucidating  tumor progression dynamics,  and thus
           the  machine  learning  algorithm  effectively  optimized   facilitating stronger anticancer therapeutic development.
           the composite bio-ink material fraction and subsequent
           printing performance [191,192] . Current applications  of   Acknowledgments
           3D bioprinting  based  machine  learning  algorithms  are   The authors would like to thank funding support by NIH
           currently geared towards using regressive models such   NIGMS MIRA award 1R35GM133794 to Dr. Mei He
           as LASSO; however, a potential avenue of integrating
           advanced  learning  systems using generative  ensembles   Conflicts of interest
           or Bayesian approaches in producing highest performing
           inks of spheroidal assembly remains completely untapped.   The authors declare no conflict of interest.
           Current existing technologies are challenged by spheroid
           precision positioning coupled with an assembly process   References
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