Is it OK to use "/" in scientific writing? For example, would it be OK to write: Many of these articles belong to School of Thought A and/or School of Thought B.

What about the other cases in general just to replace "or" with "/"?
E.g. This brain area might coincide or connect with the brain area responsible for...
Can I write it as "This brain area might coincide/connect with the brain area responsible for..."
"It's best to avoid using and/or," Mignon Fogarty, Grammar Girl, "You'd be hard pressed to find a style guide that doesn't admonish you to drop and/or and rewrite the sentence with just and or just or." 

Rather than "Many of these articles belong to School of Thought A and/or School of Thought B," try


  Many of these articles belong to School of Thought A, School of Thought B, or both.