title: Guest Editorial.
mesh_terms: D004784:Environmental Monitoring / Q000191:economics / Q000295:instrumentation; D006801:Humans; D008904:Miniaturization / Q000295:instrumentation*; D013057:Spectrum Analysis / Q000191:economics / Q000295:instrumentation*; D015813:Substance Abuse Detection / Q000191:economics / Q000295:instrumentation; D013997:Time Factors; D059015:Wireless Technology / Q000191:economics / Q000295:instrumentation