In 1973, the feds estimated that semis got about 5.6 miles per gallon of diesel; today's estimate is 6.5 mpg, although different trucks get fuel economy in a range from 4 to 8. Going up a steep hill, a truck's mileage might drop to about 2.9 mpg, while going down the same hill will raise it to more than 23 mpg. New fuel-economy standards that take effect beginning in 2014 will require semi trucks with a sleeper cab to get 7.2 mpg on level roads.
Absorbable biological suture material. Chromic is an absorbable suture made by twisting together strands of purified collagen taken from bovine intestines. Due to undergoing a ribbon stage chromicisation (treatment with chromic acid salts), the chromic offers roughly twice the stitch-holding time of plain catgut.
Your surgeon may close the deeper parts of the incision with absorbable sutures, and then use more sutures on your skin, or another type of closure such as adhesive strips or surgical skin glue. Absorbable sutures vary widely in both strength and how long they will take for your body to reabsorb them. Some types dissolve as quickly as 10 days, while other types can take about six months to dissolve. The type of suture used depends on your surgeon's preference, how strong the suture needs to be to properly support the incision and how quickly your body works to dissolve the material.