Monday, May 10, 2010
Tuesday, May 4, 2010
A Glucose BioFuel Cell Implanted in Rats
A Glucose BioFuel Cell Implanted in Rats:
Powering future generations of implanted medical devices will require cumbersome transcutaneous energy transfer or harvesting energy from the human body. No functional solution that harvests power from the body is currently available, despite attempts to use the Seebeck thermoelectric effect, vibrations or body movements. Glucose fuel cells appear more promising, since they produce electrical energy from glucose and dioxygen, two substrates present in physiological fluids. The most powerful ones, Glucose BioFuel Cells (GBFCs), are based on enzymes electrically wired by redox mediators. However, GBFCs cannot be implanted in animals, mainly because the enzymes they rely on either require low pH or are inhibited by chloride or urate anions, present in the Extra Cellular Fluid (ECF). Here we present the first functional implantable GBFC, working in the retroperitoneal space of freely moving rats. The breakthrough relies on the design of a new family of GBFCs, characterized by an innovative and simple mechanical confinement of various enzymes and redox mediators: enzymes are no longer covalently bound to the surface of the electron collectors, which enables use of a wide variety of enzymes and redox mediators, augments the quantity of active enzymes, and simplifies GBFC construction. Our most efficient GBFC was based on composite graphite discs containing glucose oxidase and ubiquinone at the anode, polyphenol oxidase (PPO) and quinone at the cathode. PPO reduces dioxygen into water, at pH 7 and in the presence of chloride ions and urates at physiological concentrations. This GBFC, with electrodes of 0.133 mL, produced a peak specific power of 24.4 µW mL−1, which is better than pacemakers' requirements and paves the way for the development of a new generation of implantable artificial organs, covering a wide range of medical applications.
http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0010476
Powering future generations of implanted medical devices will require cumbersome transcutaneous energy transfer or harvesting energy from the human body. No functional solution that harvests power from the body is currently available, despite attempts to use the Seebeck thermoelectric effect, vibrations or body movements. Glucose fuel cells appear more promising, since they produce electrical energy from glucose and dioxygen, two substrates present in physiological fluids. The most powerful ones, Glucose BioFuel Cells (GBFCs), are based on enzymes electrically wired by redox mediators. However, GBFCs cannot be implanted in animals, mainly because the enzymes they rely on either require low pH or are inhibited by chloride or urate anions, present in the Extra Cellular Fluid (ECF). Here we present the first functional implantable GBFC, working in the retroperitoneal space of freely moving rats. The breakthrough relies on the design of a new family of GBFCs, characterized by an innovative and simple mechanical confinement of various enzymes and redox mediators: enzymes are no longer covalently bound to the surface of the electron collectors, which enables use of a wide variety of enzymes and redox mediators, augments the quantity of active enzymes, and simplifies GBFC construction. Our most efficient GBFC was based on composite graphite discs containing glucose oxidase and ubiquinone at the anode, polyphenol oxidase (PPO) and quinone at the cathode. PPO reduces dioxygen into water, at pH 7 and in the presence of chloride ions and urates at physiological concentrations. This GBFC, with electrodes of 0.133 mL, produced a peak specific power of 24.4 µW mL−1, which is better than pacemakers' requirements and paves the way for the development of a new generation of implantable artificial organs, covering a wide range of medical applications.
http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0010476
Sunday, May 2, 2010
Wednesday, April 28, 2010
here we go again...
Apr 22 2010 6:25 PM EDT
Exclusive: Ridley Scott Reveals 'Alien' Prequel Details
'I've always avoided sequels, unless I felt there was something fresh,' director says of returning to 1979 classic.
http://www.mtv.com/movies/news/articles/1637638/story.jhtml
I'm not sure if this is good news or bad news...
Saturday, April 24, 2010
Darth Talon
Found this on Flickr. I don't know where the character is from but, I think She's one of the coolest things I've ever seen. Enjoy.
http://www.flickr.com/photos/sideshowcollectibles/4101622280/in/pool-sexy-figures/
Wednesday, April 21, 2010
Robot Rampage Coming this Fall
They'll kill us all! They'll kill us all!
NASA to Launch Human-Like Robot to Join Space Station Crew
NASA will launch the first human-like robot to space later this year to become a permanent resident of the International Space Station. Robonaut 2, or R2, was developed jointly by NASA and General Motors under a cooperative agreement to develop a robotic assistant that can work alongside humans, whether they are astronauts in space or workers at GM manufacturing plants on Earth.
The 300-pound R2 consists of a head and a torso with two arms and two hands. R2 will launch on space shuttle Discovery as part of the STS-133 mission planned for September. Once aboard the station, engineers will monitor how the robot operates in weightlessness.
R2 will be confined to operations in the station's Destiny laboratory. However, future enhancements and modifications may allow it to move more freely around the station's interior or outside the complex.
http://www.nasa.gov/topics/technology/features/robonaut.html
Friday, April 2, 2010
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