Where does amplification collide?

In electronics and physics, amplification means increasing the power or amplitude of a signal, so a weak input controls a much larger output drawn from a separate power supply. The ratio of output to input is called gain, and the devices that provide it, from the transistor to the operational amplifier, are the building blocks of almost all electronics. The same idea reaches into optics: in a laser, light is amplified by stimulated emission, where one photon prompts an excited atom to release a second identical photon, so the name laser stands for Light Amplification by Stimulated Emission of Radiation. Schawlow and Townes's 1958 Infrared and Optical Masers set out how such optical amplification could be built. The referent is a boosted signal or beam, measured as gain, and it is not a copied molecule, a social spiral, or a climate feedback.[1]

Unit

A boosted signal, measured as gain (output over input)

Recovery means

Not applicable

Measured by

Gain reported in decibels or as a numeric ratio, read on an oscilloscope, spectrum analyser, or optical power meter

In molecular biology, amplification means making many copies of a specific DNA sequence, so a tiny starting sample becomes enough to detect, sequence, or study. The polymerase chain reaction (PCR) does this through repeated cycles of heating and cooling that let a DNA polymerase copy the target again and again, roughly doubling it each cycle. Saiki and colleagues' 1988 Primer-Directed Enzymatic Amplification of DNA with a Thermostable DNA Polymerase, building on Kary Mullis's invention of PCR, showed how a heat-stable enzyme made the reaction practical. The word also names gene amplification in cancer, where a cell gains extra copies of a gene and can grow more aggressively. The referent is copied genetic material, counted in copy number, and it is not a boosted signal, a social spiral, or a climate feedback.[2]

Unit

Copies of a DNA sequence, counted as copy number

Recovery means

Not applicable

Measured by

Copy number tracked in real-time PCR by the cycle at which fluorescence crosses a threshold, or by gel electrophoresis of the product

In criminology and sociology, deviancy amplification names a process in which the reaction to deviance, especially by the media and authorities, makes that deviance more common rather than less. A first act draws alarmed coverage and tougher control, which can push labelled people further into a deviant role and pull in more attention, feeding what is called an amplification spiral. Leslie Wilkins set out the feedback idea in the 1960s, and Stanley Cohen's 1972 Folk Devils and Moral Panics traced how a moral panic over the Mods and Rockers grew through such a loop. The referent is a social feedback process, watched in the rates of reported deviance and in the reaction to it, and it is not a boosted signal, a copied molecule, or a climate feedback. It shares only the word with the others, though it does share the shape of a self-reinforcing loop.[3]

Unit

A self-reinforcing social reaction to deviance

Recovery means

The spiral can subside as media coverage and public concern fade and control efforts ease

Measured by

Traced through reported rates of the deviant behaviour, the volume of media coverage, and control responses over time

In climate science, amplification means a feedback that magnifies an initial change instead of damping it, so a small forcing yields a larger response. Arctic amplification is the leading example: as the region warms, bright sea ice and snow melt and expose darker ocean and land, which absorb more sunlight and warm further, a loop known as the ice-albedo feedback. Because of this and related processes, the Arctic has warmed markedly faster than the global average. Serreze and Barry's 2011 Processes and impacts of Arctic amplification: A research synthesis reviewed the mechanisms and their effects. The referent is a magnifying feedback in the climate system, measured as the ratio of local to global change, and it is not a boosted signal, a copied molecule, or a social spiral.[4]

Unit

A magnifying feedback, measured as the ratio of local to global change

Recovery means

Not applicable

Measured by

Quantified as an amplification factor comparing regional warming with the global mean, from temperature records and climate models