Provide the theme summaries for the following conversation: 

Andrew Simmons: I'm sending you the list (with specific times) for our individual meetings tomorrow. In case you are unable to attend, please let me know as soon as possible.
Andrew Simmons: <file_other>
Samuel Anderson: I have an appointment with a doctor so I won’t be able to come to the meeting.
Andrew Simmons: Then please bring your plan to our next class.
Katherine Jackson: I also won’t be coming, because I have a retake.
Andrew Simmons: Alright. For those who are coming. The meetings will take place in my office, room 104.

Summary: 
The individual meeting with Andrew Simmons takes place tomorrow in room 104. Samuel Anderson and Katherine Jackson won't attend it because he has an appointment and she has a retake.