If you have never used RSS feeds in Thunderbird, you will first need to create a feed account (Blogs and News account). To do so, in Option or Tools, open Account Settings.
In the window that pops, click at the bottom-left on Accounts Actions, and choose "Add Feed Account" or "Add Blogs and News account" (or "Add another account..." and then Blogs and News).
In the window which pops, leave the default setting « Blogs and News » or rename this title as you wish. Click Next, then Finished.
In the accounts list (window Accounts Settings that you have first opened), a "Blogs and News" account has appeared. Click on it to configure it. In the right pane of the window, check that the options "Check for new articles at start-up" and "Empty trash on exit" are selected. Deselect other options if necessary. Close the window.
In your mailbox list (left pane of the main window) a mailbox called "Blogs and News" has appeared. We will now create a folder named Seminar in this box, to store the feeds from the different institutes. Right click on "Blogs and News", and select "New folder...".
In the window that pops, enter « Seminar » as the name of the folder and click on « Create folder ».
We can now get to feed subscription per se. Right click on the « Seminar » folder that you have just created. Select « Subscribe… ».
In the window which pops, paste the address of the feed (the address you have found on this site) in the field « Feed URL », leave default settings for the rest. Click on Add. Congratulations, your first RSS Feed has been added. Click on close (or add other feeds).
Repeat the same procedure to add other feeds. Right click on « Seminar », « Subscribe... », enter the address of the feed, click on "Add" and close the window.