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.
The Best Materials to Cover your Greenhouse. 1  Glass: The traditional greenhouse covering, glass is the preferred material for permanence. 2  Film Plastic: Film plastic is one sixth to one tenth of the cost per square foot of a glass covered structure.
Lean To Greenhouses. Browse our excellent range of Lean to Greenhouses for sale from the world's leading aluminium greenhouse manufacturers such as Vitavia, Halls, Eden, Rion, Elite greenhouses. We also offer the superb lean to wooden greenhouses from Swallow GB in 4ft, 6ft and 8ft widths that include installation in the price.