Conversation so far:
Where was Tu youyou born?
Tu youyou was born in Ningbo, Zhejiang, China
When was tu youyou born?
Tu youyou was born on 30 December 1930
Where did Tu youyou do her university studying?
Tu youyou attended Peking University Medical School / Beijing Medical College.
Are there any interesting facts you can tell me about tu youyou?
After graduation, Tu youyou worked at the Academy of Traditional Chinese Medicine in Beijing
What kind of work did tuyouyou do at the traditional medicine academy?
Tu youyou did research
What did Tuyouyou primarily research?
Tu youyou studied Lobelia chinensis, a traditional Chinese medicine for curing schistosomiasis
What was tu youyou's family life like?
What job does Tu youyou currently hold?
Tu Youyou is a Chinese pharmaceutical chemist and malariologist
Is there anything else interesting you'd like to share about tu youyou?
Tu Youyou is regarded as a “three nos” professor

Question: What does the three nos mean?
Self-contained rewrite: What does tu youyou being regarded a three nos  professor mean?