U Pitt PhD申请文书的疑问（Scholarly Research or Professional Writing ）

lz打算申请18fall的匹大CS PHD，在网申界面查看文书时发现需要提交两份文书：
1.an essay (not exceeding 1,000 words) indicating, as specifically as possible, your academic and professional goals. Please identify potential areas and/or topics in which you expect to pursue dissertation research.

2.Scholarly Research or Professional Writing

第一个应该就是research proposal, 不过第二个文书是什么意思呢？
求好心人解答{:4_112:}