Diabetes

Monitoring glucose levels, no needles required

Noninvasive glucose monitoring devices are not currently commercially available in the United States, so people with diabetes must collect blood samples or use sensors embedded under the skin to measure their blood sugar ...

Cardiology

Damaged hearts rewired with nanotube fibers

Thin, flexible fibers made of carbon nanotubes have now proven able to bridge damaged heart tissues and deliver the electrical signals needed to keep those hearts beating.

Medical research

Atomic nano-switches emulate human memory

In a breakthrough, researchers at the International Center for Materials Nanoarchitectonics (MANA, Japan) demonstrate for the first time the key features in the neuroscience and psychology of memory by a AgS2 synapse.

Neuroscience

Protecting the brain when energy runs low

Researchers from the Universities of Leeds, Edinburgh and Dundee have shed new light on the way that the brain protects itself from harm when 'running on empty.'

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Electrical conductivity

Electrical conductivity or specific conductance is a measure of a material's ability to conduct an electric current. When an electrical potential difference is placed across a conductor, its movable charges flow, giving rise to an electric current. The conductivity σ is defined as the ratio of the current density to the electric field strength :

It is also possible to have materials in which the conductivity is anisotropic, in which case σ is a 3×3 matrix (or more technically a rank-2 tensor) which is generally symmetric.

Conductivity is the reciprocal (inverse) of electrical resistivity, ρ, and has the SI units of siemens per metre (S·m-1):

Electrical conductivity is commonly represented by the Greek letter σ, but κ (esp. in electrical engineering science) or γ are also occasionally used.

An EC meter is normally used to measure conductivity in a solution.

This text uses material from Wikipedia, licensed under CC BY-SA