@article{14901,
  abstract     = {Global services like navigation, communication, and Earth observation have increased dramatically in the 21st century due to advances in outer space industries. But as orbits become increasingly crowded with both satellites and inevitable space debris pollution, continued operations become endangered by the heightened risks of debris collisions in orbit. Kessler Syndrome is the term for when a critical threshold of orbiting debris triggers a runaway positive feedback loop of debris collisions, creating debris congestion that can render orbits unusable. As this potential tipping point becomes more widely recognized, there have been renewed calls for debris mitigation and removal. Here, we combine complex systems and social-ecological systems approaches to study how these efforts may affect space debris accumulation and the likelihood of reaching Kessler Syndrome. Specifically, we model how debris levels are affected by future launch rates, cleanup activities, and collisions between extant debris. We contextualize and interpret our dynamic model within a discussion of existing space debris governance and other social, economic, and geopolitical factors that may influence effective collective management of the orbital commons. In line with previous studies, our model finds that debris congestion may be reached in less than 200 years, though a holistic management strategy combining removal and mitigation actions can avoid such outcomes while continuing space activities. Moreover, although active debris removal may be particularly effective, the current lack of market and governance support may impede its implementation. Research into these critical dynamics and the multi-faceted variables that influence debris outcomes can support policymakers in curating impactful governance strategies and realistic transition pathways to sustaining debris-free orbits. Overall, our study is useful for communicating about space debris sustainability in policy and education settings by providing an exploration of policy portfolio options supported by a simple and clear social-ecological modeling approach.},
  author       = {Nomura, Keiko and Rella, Simon and Merritt, Haily and Baltussen, Mathieu and Bird, Darcy and Tjuka, Annika and Falk, Dan},
  issn         = {1875-0281},
  journal      = {International Journal of the Commons},
  keywords     = {Sociology and Political Science},
  number       = {1},
  publisher    = {Ubiquity Press},
  title        = {{Tipping points of space debris in low earth orbit}},
  doi          = {10.5334/ijc.1275},
  volume       = {18},
  year         = {2024},
}

@inproceedings{14862,
  author       = {Rella, Simon and Kulikova, Y and Minnegalieva, Aygul and Kondrashov, Fyodor},
  booktitle    = {European Journal of Public Health},
  issn         = {1464-360X},
  keywords     = {Public Health, Environmental and Occupational Health},
  number       = {Supplement_2},
  publisher    = {Oxford University Press},
  title        = {{Complex vaccination strategies prevent the emergence of vaccine resistance}},
  doi          = {10.1093/eurpub/ckad160.597},
  volume       = {33},
  year         = {2023},
}

@article{9905,
  abstract     = {Vaccines are thought to be the best available solution for controlling the ongoing SARS-CoV-2 pandemic. However, the emergence of vaccine-resistant strains may come too rapidly for current vaccine developments to alleviate the health, economic and social consequences of the pandemic. To quantify and characterize the risk of such a scenario, we created a SIR-derived model with initial stochastic dynamics of the vaccine-resistant strain to study the probability of its emergence and establishment. Using parameters realistically resembling SARS-CoV-2 transmission, we model a wave-like pattern of the pandemic and consider the impact of the rate of vaccination and the strength of non-pharmaceutical intervention measures on the probability of emergence of a resistant strain. As expected, we found that a fast rate of vaccination decreases the probability of emergence of a resistant strain. Counterintuitively, when a relaxation of non-pharmaceutical interventions happened at a time when most individuals of the population have already been vaccinated the probability of emergence of a resistant strain was greatly increased. Consequently, we show that a period of transmission reduction close to the end of the vaccination campaign can substantially reduce the probability of resistant strain establishment. Our results suggest that policymakers and individuals should consider maintaining non-pharmaceutical interventions and transmission-reducing behaviours throughout the entire vaccination period.},
  author       = {Rella, Simon and Kulikova, Yuliya A. and Dermitzakis, Emmanouil T. and Kondrashov, Fyodor},
  issn         = {20452322},
  journal      = {Scientific Reports},
  number       = {1},
  publisher    = {Springer Nature},
  title        = {{Rates of SARS-CoV-2 transmission and vaccination impact the fate of vaccine-resistant strains}},
  doi          = {10.1038/s41598-021-95025-3},
  volume       = {11},
  year         = {2021},
}