Jul 26, 2010

Reprogrammed Stem Cells Remember Their Past

While reprogrammed stem cells--those derived from fully differentiated adult cells--can be transformed into any type of tissue, scientists have now discovered that they preserve a memory of where they came from. That memory appears to influence the cells' development; reprogrammed stem cells are more easily converted back to their original identity, according to a study released online today in Nature. The findings could affect research into the two main uses for reprogrammed stem cells; growing efforts to study disease in cells derived from patients with those diseases, and the development of replacement cell therapies.

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Jul 12, 2010

Fabricating a Multifunctional Fiber

Fibers that carry light and sense pressure could be used for medical imaging and structural monitoring. Researchers have developed optical fibers that not only carry and modulate light, but also generate and sense pressure changes. The multifunctional fibers could be used to make various types of sensors. The fibers can also be squeezed in a way that modulates an optical signal, making them promising for "smart" textiles.

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Jul 1, 2010

Harvesting heat to power electronics

Thermoelectric (TE) energy harvesting is based on the heat flux through a thermoelectric element. The heat flux is driven by a temperature difference across the element. The generated voltage is proportional to the number of elements and the temperature difference.

The TE-Power Node uses any source of thermal energy to drive a wireless transceiver, storing power in a thin-film battery. The Node is a test bed for designers looking to build the next generation of sensor networks, in which the sensors power themselves by harvesting energy from the environment. The battery stores the power that trickles in from sources such as a warm industrial exhaust pipe and then releases the accumulated energy in a pulse powerful enough to operate the radio. A 10 °C difference in temperature produces enough electricity to transmit 13 bytes of information per second.

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