The invention provides intrafallopian devices and non-surgical methods for their placement to prevent conception. A number of vertical support posts vertically disposed within the bores are fixed to the module beneath the top surface. Especially, the UE feeds back indication information indicating a combination of the M best subbands from among combinations each having M subbands produced out of a maximum number of subbands that can be allocated. Thus, a high-level signal is outputted from the comparator and a low-level signal is inputted to a driver via an inverter, so that the driver turns off a backlight. The mixture includes sufficient coarse substrates to provide the reactor with at least 100 square meters of surface area per cubic meter of reactor space. The method further includes providing, by the node, the evacuation route to the one or more additional nodes.