1. Oncologists: Oncologists are medical doctors who specialize in the diagnosis and treatment of cancer. They work with patients to develop personalized treatment plans that may include surgery, chemotherapy, radiation therapy, and other interventions to combat cancer. 2. Environmental scientists: Environmental scientists study the impact of human activities on the environment and work to develop solutions to environmental problems. They may focus on issues such as pollution, climate change, deforestation, and biodiversity loss. 3. Astrophysicists: Astrophysicists study the physical properties of celestial objects such as planets, stars, galaxies, and black holes. They use mathematical models and observational data to understand the origins and evolution of the universe. 4. Neuroscientists: Neuroscientists study the structure and function of the brain and nervous system. They investigate how the brain processes information, controls behavior, and regulates bodily functions, and may research conditions such as Alzheimer's disease, Parkinson's disease, and epilepsy. 5. Marine biologists: Marine biologists study marine organisms and ecosystems, including fish, corals, plankton, and marine mammals. They may research topics such as ocean conservation, pollution, climate change, and the impact of human activities on marine biodiversity.