Deposition, exhumation, and paleoclimate of an ancient lake deposit, Gale crater, Mars.

The landforms of northern Gale crater on Mars expose thick sequences of sedimentary rocks. Based on images obtained by the Curiosity rover, we interpret these outcrops as evidence for past fluvial, deltaic, and lacustrine environments. Degradation of the crater wall and rim probably supplied these sediments, which advanced inward from the wall, infilling both the crater and an internal lake basin to a thickness of at least 75 meters. This intracrater lake system probably existed intermittently for thousands to millions of years, implying a relatively wet climate that supplied moisture to the crater rim and transported sediment via streams into the lake basin. The deposits in Gale crater were then exhumed, probably by wind-driven erosion, creating Aeolis Mons (Mount Sharp).

Personality characteristics of chronic bruxers.

One hundred twelve adults randomly selected from a periodontal practice participated in research to determine whether the personality traits of people who chronically brux (grind their teeth) diverge significantly from the personality traits of those who do not do so. All participants completed a personality questionnaire and were examined by the periodontist, who determined which were chronic bruxers. Twenty-eight of the men and 46 of the women were diagnosed as bruxers. Their personality trait scores differed significantly from those of the nonbruxers. In general, and regardless of gender, chronic bruxers were found to be shy, stiff, cautious, and aloof, preferring things rather than people, avoiding compromises, rigid in their ways, affected by feelings of inferiority, impeded in expressing themselves, apprehensive, and given to worrying.