Progress report — July 2003 to June 2 0 0 4 Directorate General for the Internal Market, Unit A 4 Internal and external communication Introduction The new version of the Citizens' Signpost Service (CS[.]
Plants are known in which at least the following processes are controlled by photope- riod: flowering, tuber formation, seed germination, vegetative development, tissue differentiation and induction or termination of dormancy of buds, bulbs, etc. (Thomas, 1998). In plants, photoperiodic perception occurs in the young expanded leaves (Lang, 1965; Vince-Prue, 1975). The first clear observation of photoperiodism was reported in tobacco Nicotiana tabacum, which only flowered and set seeds when given 10 hours light and 14 hours of darkness per day in the lab, while those living under the long days in the field remained vegetative (Garner, 1920). Following this study, it was found that chlorosis and decreased growth of tomato plants caused by continuous light could be prevented by subjecting the plants to light-dark cycles in the context of 24 hours (Hillman, 1956), which demonstrated a protective effect of plants’ responses to photoperiod. After the molecular genetic identification of photoreceptors and light-signaling components in plants, further progress in photoperiodism has been made. Most recently, the expression of the floral regulator gene CONSTANS shifts either at dawn or at dusk, depending on the daylength, which suggested that the pho- toperiodic perception in Arabidopsis was mediated by adjustments in the phase of en- trainment to the daily light:dark cycle (Roden, 2002; see 1.3).
Greatest 1 _______ 2 _______ 3 _______ 4 _______ 5 _______ 6 _______ Least OR, The magnitude of the force on the spaceship is the same but not zero for all these locations. ___ OR, The magnitude of the force on the spaceship is zero for all these locations. ___ OR, The ranking of the magnitude of the force on the spaceship cannot be determined. ___ Explain your reasoning.
In recent decades, industrialized countries also included the thermal treatment (incineration, pyrolysis, or gasification) of MSW as an important option for its management. Within thermal treatments, incineration has reached a great interest. However, although this process notably reduces the space required for the disposal of the same amount of residues in landfills (typically by a factor from 4 to 10) [1- 3], MSW incinerators (MSWI) have been questioned because of the atmospheric emissions of acid gases, heavy metals, polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), and especially by the emission of the potential carcinogenic agents polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) [1, 2, 4-6].