Answer:
I will say chemical which is drug, in this aspect we should be looking at drug abuse. Too much misuse of drugs can affect the brain,mainly causes of mental illnesses can be traced to the brain. An example of drug abuse is the intake of cocaine to make one high. Symptoms include being unreasonable,nuisance and even paranoia.
A. The fact that it is lengthy and in narrative form
Answer: If I was the employee, I probably would have at least got a coffee if I am working extra hours, I would make sure I lock the files back in their designated spot, and before clocking out, I would make sure I wouldn't have any hospital property with me. And if i need to bring home something from the hospital, then I would make sure I have everything with me before I get off the train.
Explanation: If I was one of those patients, I would worry about someone using my name to get info on everything about me like my insurance provider, social security, credit cards, what I have, and what the person with my documents would end up doing with them. Another thing I would worry about was getting blackmailed or not being able to get the medicine I need because another person is impersonating me.
They use quorum sensing; cell to cell. Which gives larger groups of organisms syncronizing abilities for activities.