Diseases, Conditions, Syndromes

How cholera bacteria make people so sick

The enormous adaptability of the cholera bacterium explains why it is able to claim so many victims. Professor Ariane Briegel from the Leiden Institute of Biology has now discovered that this adaptability is due to rapid ...

Medical research

With mini-vessels, mini-brains expand research potential

Scientists have recently made a wondrous variety of mini-brains—3-D cultures of neural cells that model basic properties of living brains—but a new finding could add to the field's growing excitement in an entirely new ...

Immunology

Immune cells cast nets to save us from harm

Our immune cells can undergo a spectacular form of cell death, using their own DNA to make nets that kill infectious microbes. Now for the first time, advanced microscopy techniques have allowed scientists to visualise details ...

Oncology & Cancer

To stop cancer's spread, take out its communication channels

Metastasis - or the spread of cancer from one part of the body to other parts - accounts for more than 90 percent of cancer-related deaths. Although the cells that seed metastasis and the sites that they tend to travel to ...

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Electron microscope

An electron microscope is a type of microscope that uses a particle beam of electrons to illuminate a specimen and create a highly-magnified image. Electron microscopes have much greater resolving power than light microscopes that use electromagnetic radiation and can obtain much higher magnifications of up to 2 million times, while the best light microscopes are limited to magnifications of 2000 times. Both electron and light microscopes have resolution limitations, imposed by the wavelength of the radiation they use. The greater resolution and magnification of the electron microscope is because the wavelength of an electron; its de Broglie wavelength is much smaller than that of a photon of visible light.

The electron microscope uses electrostatic and electromagnetic lenses in forming the image by controlling the electron beam to focus it at a specific plane relative to the specimen. This manner is similar to how a light microscope uses glass lenses to focus light on or through a specimen to form an image.

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