We demonstrate that an organic Mott insulator, 0 -(BEDT-TTF) 2 ICl 2 , is metallized by application of extremely high pressure by means of the cubic anvil press. When the metallic state is stabilized, superconductivity with the highest transition-temperature (T c ) among the organic systems appears. The lower limit of the pressure at which the superconducting transition manifests itself is approximately 7.0 GPa and T c reaches a maximum value, 14.2 K (onset), at 8.2 GPa. The pressure-temperature phase diagram is constructed and discussed in terms of the comparison with those of other organic systems.

The jaw muscle anatomy of the northern grasshopper mouse, Onychomys leucogaster, was observed and the mechanical basis of the insectivorous/carnivorous adaptations were examined. Compared with Peromyscus maniculatus, a granivorous relative of Onychomys, there is a reduction of some aponeuroses within the masseter deep layer. This characteristic indicates that shearing meat or crushing arthropod exoskeletons requires less occlusal pressure than does grinding plant material. In Onychomys both the anterior and posterior portions of the masseter deep layer are more anterodorsally inclined, so that the line of action of the masseter lies further from the jaw joint than in Peromyscus. A strong incisal bite for killing vertebrates such as other rodents can be produced by a jaw mechanism with the high lever advantage of this muscle, which compensates for the decline in muscle mass. Our quantitative analysis suggests that the disappearance of an aponeurosis along the zygomatic plate in Onychomys decreases the stretch of the corresponding muscle, i.e., the anterior fibers of the masseter deep layer, accompanying jaw opening, and increases the maximum gape necessary for hunting large prey.

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