Key for Hexagonal Diamond Formation: Theoretical and Experimental Study.

Hexagonal diamond (HD) was reported 60 years ago and has attracted extensive attention owing to its ultrahigh theoretical hardness, 58% superior to its cubic counterpart. However, to date, synthesizing pure HD under high-pressure and high-temperature (HPHT) remains unsuccessful due to the limitations of understanding the formation mechanism. In this work, employing a systematic molecular dynamics simulation, we directly observe the graphite-to-HD transition in a nucleation-growth mechanism.

[Outcome and relevant factors of tubal pregnancy treated with laparoscopic conservative surgery].

Objective: To investigate the therapeutic outcome and its influencing factors after laparoscopic conservative surgery in treatment of tubal pregnancy.

Methods: From January 2003 to December 2008, 226 cases with tubal pregnancy were treated by laparoscopic conservative surgery. The tubal patency was evaluated in 152 cases given by hysterosalpingography (HSG) and 6 cases given by second laparoscopic exploration at 3 - 6 months after surgery.