Treat freshmen and new hires like future colleagues. Most of them will be.

The new person is temporary only in the sense that the newness wears off. In a year or two they are standing beside you carrying a precise memory of how they were treated, and deciding how much to help you on that basis. Groups that are rough on newcomers rebuild that roughness every single year. The time to be decent about it is while it still costs you something.

Learn the names of the newest people this week and use them. Answer one question you find obvious without making the person feel slow. Treat them as somebody you will still know in three years.