In the US, is it culturally acceptable for a graduate student to give a small gift to a professor? I am an overseas student who was recently admitted to a PhD program in the US, and I will soon travel to the US to meet my future PhD advisor and my fellow grad students. My future PhD advisor has also kindly accepted to be my host for the duration of the several days I will spend in the US. I really appreciate his help, as I know hosting a student in addition to all the other responsibilities that come with being a professor may be a hassle, and also he has saved me from paying for a B&amp;B by offering to host me. 

Anyway, I think I would like to give a small gift to my professor just as a token of appreciation for his consideration, but I have doubts as to whether this would be appropriate, since I come from a different culture, and I cannot easily assess how people would react to such a thing in the US. In my culture, too, it would be inappropriate to buy an expensive gift for a professor. In the best case, the professor would sternly refuse to accept the gift, and in the worst case, the professor could have negative ideas about you, e.g., s/he could think you were trying to ingratiate yourself with him/her, that you intended to give the gift as a form of bribe, etc. BUT a small gift with little to no monetary value wouldn't be turned down, and it would most probably be accepted as a token of heartfelt thankfulness. The question for me is, of course, where this boundary is in the US. 

And in case you're wondering what I consider buying for him...well, my country happens to have nice tea sets and/or plates made of porcelain, they are popular souvenirs that tourists like to buy here, and one can easily buy a nice, small decorative plate for under 10 dollars, for instance. So I suppose I could buy something like that. 

Would that be acceptable? Or would I be judged negatively? 

Thank you very much in advance for your answers.
As your Ph.D. advisor is also going to be your host and provide you with lodging during your stay, a small gift would be very acceptable.  It is accepted etiquette in the U.S. to leave your host a small gift as a token of your appreciation for their hospitality to you.  You may want to give your host a gift card to a restaurant in their area placed inside a thank you card.  This can also be done online and sent to your host via email.  Both ways would be done after your stay is complete.  Another idea would be to send flowers after your visit.  Small tokens such as these that would be enjoyed by the whole household are wonderful ways to say "thank you".