Most commonly, patients describe acute tenderness in the buttock and sciatica-like pain down the back of the thigh, calf and foot. Typical piriformis syndrome symptoms may include: 1  A dull ache in the buttock. 2  Pain down the back of the thigh, calf and foot (sciatica).
We think of ice as snowflakes, ice cubes, snow cones, and dangerous patches on the sidewalk. Scientists have many different ways of categorizing ice too! There are actually fourteen types of ice that exist in different environments.
Dry ice is made of solid carbon dioxide (CO2) while ice is made, of course, of solid water. Almost all substances have a freezing point which depends on their unique physical and chemical characteristics. I'm not sure,though, how well we understand why a particular substance has the exact melting point it does.