In DSM, nicotine dependence is included under the general definition of substance dependence.  The essential feature of Substance Dependence is a cluster of cognitive, behavioral, and physiologic symptoms indicating that the individual continues use of the substance despite significant substance-related problems.
Greenhouse Covering. Whether you're replacing existing greenhouse coverings or building a greenhouse you're sure to find the best greenhouse covering at FarmTek. Greenhouse glazing is the material that covers the greenhouse frame and the most widely used materials are polycarbonate and poly film.
Each plant requires Â½ to 1 cubic foot of growing medium. A number of growing media - peat based, bark based, coir based, soil based and muck peat based potting soil - were used in the greenhouse tomato trials at UK in 1995.