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.
We need plants to conserve and recycle resources, helping maintain a breathable atmosphere and a drinkable water supply. Much easier said than done. In order to build a space greenhouse that doesnât eventually kill us, we first need to understand how plants make a living and how theyâve shaped our planet.