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Fingure Plethysmography

SOURCE:https://instruct1.cit.cornell.edu/courses/ece5030/labs/f2009/Plethysmograph.html

• Instead of a LED, an IR emitter can also be used• You can see a slight glow in the IR emitter (on the left) because the camerais slightly sensitive to infrared light. The Phototransistor is the black device just to the right Here a LED and LDR is used for the measurement of heartrate

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Plethysmograph – Piezoelectric pulsetransducer

SOURCE:http://www.ufiservingscience.com/transducers.html

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Contact Microphone forphonocardiography

SOURCE:http://www.harvardapparatus.com/webapp/wcs/stores/servlet/haisku4_10001_11555_61675_-1_HAI_ProductDetail_N_37757_41451_41452_41453

SOURCE:http://dc255.4shared.com/doc/sLtLy

doQ/preview.html

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Impedance Plethysmography

4 – electrodes used forimpedance plethysmography

SOURCE:

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Impedance Plethysmography• Impedance Cardiovasograph system developed at

BARC. The data acquisition system is connected to righthand of the control subject with the help of electrodes.

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EEG Disk Electrodes

Source:https://wiki.engr.illinois.edu/display/BIOE414/EEG

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• Disk and Cup electrodes are generally made of high purity tin,silver, gold or even surgical steel, or some combination ofthese (i.e. gold plated silver).

• They usually have a diameter that is within 4-10 mm assmaller than 4mm, or larger than 10mm, will not makesufficient mechanical/electrical contact with the scalp.

• The application site is determined and prepared by sterilizingwith alcohol, using an abrasive to remove dead skin.

• Once the electrode is secure, the cup is filled with aconductive gel which aids conductivity.

• These electrodes can also be placed on other parts of thebody to monitor skin potentials and filter these out,increasing the reliability of the readings.

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EEG Needle Electrodes• Needle electrodes are

sterilized, single-useneedles placed under theskin.

• These electrodes aretypically made of surgicalgrade steel and are inserted

into the scalp afterthorough disinfection of theinsertion site.

Source:https://wiki.engr.illinois.edu/display/BIOE414/EEG

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• The advantage of this particular type ofelectrode is fast application, perhaps beinguseful in emergency situations or on comatosepatients; however the invasive nature of theapplication and pain caused to the patient

means that they are not commonly used.• These electrodes also have a risk of infection

and unfavorable electrical behavior due to

their shape.

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EEG• During an EEG, flat metal discs (electrodes)are attached to your scalp.• The electrodes are connected to the EEGmachine with wires.• Some people wear an elastic cap fitted withelectrodes, instead of having the adhesiveapplied to their scalps

SOURCE:http://www.mayoclinic.org/procedure/eeg/multimedia/eeg-electrodes/IMG-20005916

• An EEGrecords the electricalactivity of your brain via electrodesaffixed to your scalp.EEG results show changes in brainactivity that may be useful indiagnosing brain conditions, especiallyepilepsy and otherseizure disorders.