Questions about parameters in nfapi_interface.h

[w840922]

There are two questions about parameter's type in nfapi_interface.h.
1.The PDU index in the Table 4-45 NPDCCH PDU Release 13 parameters.
I found it use int16_t but in spec it was be defined as uint16_t like the figure shows , can you explain it?

2.The Scrambling sequence initialization Cinit inTable 4-103 NULSCH PDU Release 13 parameters.
It use uint16_t but in spec it was be defined as uint8_t like the figure shows , can you explain it?