The medical-physics tag has no wiki summary.
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How do you calculate the equivalent absorbed radiation dose from activity, type of emission, and the energy of the emission?
I have a sample of U-238 of which my Geiger counter detects beta activity at 700 events per second. Based on the counter's efficiency of 98.6% for U-238, the activity would be about 710 becquerels, I ...
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How is it possible for an Ultrasound device to correctly interpret a negative density change in tissue?
I understand the principles of Ultrasound Imaging, and the mathematics behind sonar velocity, impedance, and reflection.
I also understand that an Ultrasound device recieves an echo produced by ...
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Equivalences for mCi doses and Rads?
What would be the magnitude of radiation received for a 50mCi dose of radioiodine I-31 as compared to say RADS? I read that it might be on the order of about 35 RADS. Does this make sense?
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Is metabolic rate the amount of heat given off?
The Basal Metabolic Rate is intuitively expressed as "the amount of energy you consume just sitting around." In some places it seems to be equated with the amount of heat that you give off.
Is this ...
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1answer
137 views
Why (infra-)red light is not used in diagnostics?
I noticed that human body conducts red visible light quite well. A hand placed over a powerful red lamp seems to be semi-transparent while over any other color it does not.
Possibly the light ...
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3answers
340 views
Nanorobots. What stops us from producing them yet?
If we can already predicts accuratelly motion on molecular levels, what stops us from developing small robots to, for instance, navigate through our blood vessels looking for cancerous cells and ...
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2answers
831 views
How does fluoroscopy (x-ray) imaging work in practice?
I know the basics, that by measuring how much x-ray signal reaches each 'pixel' on the receiver we can measure how much has been absorbed. But this gives only a single channel of information, e.g a ...
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Proton therapy in cancer treatment
Why are protons used in cancer therapy ? Is there any advantages compared to classics X-rays treatment or electron treatment ?
