Thursday, April 22, 2010

Electricity and the Heart

Here's a timeline of historical events in electrophysiology. You can click on each decade to see many more events that occurred in that decade.

http://www.hrsonline.org/News/ep-history/timeline/index.cfm

Thursday, March 11, 2010

Avatar is all about EEG

In a sense, AVATAR is a manifesto of the power and possibilities of EEG. Was James Cameron inspired by EEG?

"the neurons are the cells which controls our whole body. And for example you can see it in visual that is the movie AVATAR. Actually when I saw that movie, I could feel the imaginations and creativity only, but when I read about the neurons, then I understood that the concept of movie was all about the neurons and its working has been shown tremendously in the movie."

http://www.modexpression.com/2010/01/science-fact-in-movie-avatar.html

The technology of using brain to control an avatar in video games are emerging. Then, the term 'Avatar' may have another meaning.

Make your own EKG

If you're really daring and curious

http://hackaday.com/2008/05/26/make-an-ecg-with-your-sound-card/

Dynamic Clamp

The use of channel blocking drugs to study different ion channels makes one wonder if there is a less destructive manner to study channel behavior. The Dynamic clamp provides just that.

The Dynamic clamp is an evolution of the voltage clamp which can be used to simulate dynamic processes such as membrane of synaptic currents in living cells.The operation is as follows:

A living cell is contacted with one or several electrodes and its membrane potential V is amplified and fed into the dynamic clamp machine. The dynamic clamp machine contains a model of the membrane or synaptic conductance(s) to be inserted in the living cell(s), either in the form of equations (for digital dynamic clamp systems) or in the form of a dedicated electrical circuit (for analog systems). The dynamic clamp system computes the current(s) I generated by the modeled conductance(s) and outputs it in real-time. That current is injected into the living cell, which therefore receives the same current as if it contained the membrane or synaptic conductance modeled with the dynamic clamp.

More details here

Tuesday, March 9, 2010

EKG simulator

Great way to learn how to read an EKG.

http://www.skillstat.com/ECG_Sim_demo.html

Exoskeletons

Exoskeletons supplement human movement by reading EMG signals to determine the intent of the user: http://www.youtube.com/watch?v=-w_YV_37ZEY&feature=youtube_gdata

Wednesday, February 24, 2010

So sharks have these sensing organs(electroreceptors) called Ampullae of Lorenzini which detect the presence of other fish around them due to the fields created from electrical impulses. This video shows how a strong magnetic field can deter sharks and prevent bites. Other animals have it too besides the shark. kind of interesting how sensitive these receptors are. according to the wikipedia page, they are sensitive enough to detect 5nV/cm fields.

http://www.youtube.com/watch?v=u5vzmnkCU6I

Sunday, February 21, 2010

Yay for electrical engineers contributing to biological research.

Yay for electrical engineers contributing to biological research.

One of my old mentors always said, "Measure what you want to measure!"
(and its corollary,)
"You cannot study what you cannot measure."

Here is an example of how finding/innovating the right tool for the job helps to pinpoint the mechanism of a genetically-linked cause of diabetes that has been very difficult to study (until now).

Yay for electrical engineers contributing to biological research.

"Perhaps the Investigators were lucky in this case, but their findings tell us that the method for measuring islet function precisely matches the defective pathway - such as the use of electrical monitoring of impaired insulin granule fusion [(at the cell vesicle membrane)] - the genetic effect is [finally seen as being quite significant contributor]."

http://content.nejm.org/cgi/reprint/362/4/361.pdf

NEJM 362;4 Jan 28, 2010
They implicate an "alpha 2 adrenergic receptor" (the adrenalin / norepinephrine receptor)
(stress --> adrenalin --> dysfunctional receptor mechanism described in article --> over time --> big risk for diabetes).

Friday, February 19, 2010

Channel Energy

It has been bothering me that we have been ignoring energy except for one slide early on. This is a quick video that explains the mechanics of the energy component for the channels (highschool bio basically).

http://www.youtube.com/watch?v=iA-Gdkje6pg
(elaborates more on what Ari's video mentions)

Thursday, February 18, 2010

Transatlantic cable

The cable was indeed laid by having two boats meet in the middle of the ocean, although it took several attempts. See http://en.wikipedia.org/wiki/Transatlantic_telegraph_cable#Transatlantic

While that article does not mention Peter Cooper, this was taken from his wikipedia page. "In 1854, Cooper was one of five men who met at the house of Cyrus West Field and formed the New York, Newfoundland and London Telegraph Company. He was among those supervising the laying of the first Transatlantic telegraph cable in 1858."

Brain- Computer interface

For patients with neuromuscular disorders, MLS etc.

http://www.slideshare.net/guest9006ab/braincomputer-interfaces

Thoroughly explains each state of the AP and what is happening in/out of the membrane

http://bcs.whfreeman.com/thelifewire/content/chp44/4402s.swf

Action Potential Video

This video does a thorough job explaining how an action potential travels down an axon:

Wednesday, February 17, 2010

Action Potential Animation

http://outreach.mcb.harvard.edu/animations/actionpotential.swf

This interactive animation on action potential explains different stages of action potential in terms of sodium and potassium ions movement across the membrane through sodium channel, potassium channel and a Na+/K+ pump.