H1-B For Researcher and Tax Treaty

Question

Hi,

I am a Researcher for a US University under the H1-B Visa. I come from France and started my work March 11, 2013.
From my arrival to December 31, 2013 I claimed the tax treay and get an exemption of Federal and State Tax.

Now we are in January 2014, and I dont know if I can still be exempted by the tax treaty or not.

So to sum-up:

- H1-B Visa
- Research for a US University
- Arrivale date : March 16, 2013
- Tax Treaty with France

If you can help with this it will be really helpfull !

Thanks you all