Maize tissue may be regenerated from nodal extracts prepared from germinated mature seeds and germinated embryos grown in a medium containing plant growth regulators. The plug periphery is expanded into gas-tight sealing contact with the fitting inner periphery by means affording installation and removal without tools. The captured potential energy of harvested rainwater at high altitudes provides the energy required for redistribution of rainwater from regions with high precipitation rate to regions with low precipitation rate. The duplexer may be adjusted to changing environments or desired changes in the frequency of operation, reducing circuitry architecture and providing greater flexibility in communication function.