Does anyone know if/how can you tweet just a group that you have made in tweetdeck?

Which then all tweets on Science Friday will need to be searched by hand. They could have used a #hashtag (e.g. #scifri instead ,thus clumping the event messages) to achieve the same objective. Follow @scifri to get our updates, and tweet your questions and comments to us during the program.

I have hyperlinked the relevant portion of their message. So there are three ways I know that you could have found their account on twitter. Any would lead to their twitter account.

Now I do not know much about scifri but it does not seem like they acknowledge receipt of your mentions via their account. Maybe during their podcast (Fridays, 2-4 pm Eastern time), the interesting comments/questions are selected for the rest of the audience to see. Companies also tend to use Twitter to try to persuade users into writing shorter questions (getting content into 140 characters) so that they can read and respond as quickly as it was sent.