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Some practical information first - the charged particle beam passing through the matter suffers from energy (and also angular) straggling. That means that even if an ideally monoenergetic beam is used, there will be always a finite volume with Bragg peak losses. The bigger initial energy, the bigger is the volume. Protons stopping at 40 mm have straggling ...


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Let's suppose you have swallowed one of the Po-210 sources from this student kit. Its activity is 3700 Bq (0.1 ╬╝Ci). Based on the Table 6 in the meta-study [1], it is probably safe to ingest up to 0.02 MBq/kg of the Po-210. This means, that for 80 kg person, it is probably safe to ingest 1.6 MBq of the Po-210, so you "need" to eat approx. 400 of these ...


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Here is what wiki has to say about Polonium radiological toxicity: By mass, polonium-210 is around 250,000 times more toxic than hydrogen cyanide (the LD50 for 210Po is less than 1 microgram for an average adult (see below) compared with about 250 milligrams for hydrogen cyanide[66]). The main hazard is its intense radioactivity (as an alpha ...


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See if this argument works - I am making this up on the spot so there is definitely space for argument... Most of the interactions with the electrons will not be "head-on collisions" but rather electrostatic interactions. If we get to a certain distance of an electron, it will feel the force and undergo acceleration. If the time of the interaction is short, ...


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The dose that kills a tumor is deliberately aimed at that tumor. If, instead of using a collimated beam, you put a person in a wide beam for radio "therapy", you would be treating their entire body as a tumor and kill them. The dose in RT is computed locally - "this" part of the body (these grams of tissue) absorbed (were exposed to) "this many" Joules of ...


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Everyone is likely to have a similar pain threshold to electric shocks. If your friend wears leather soled shoes he will conduct static electricity to earth because they offer much less resistance to earth than rubber or plastic soled shoes. Wearing synthetic clothes may cause a similar effect. If he/she has lower resistance than you (by having sweaty ...


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I am a medical physicist working in a Radiation Oncology department. MLCs are used for both 3D and IMRT plans. In fact, very few hospitals have the ability to make/use the lead blocks anymore. The MLCs define the shape of the radiation field. 3D treatment plans are generated with the user (often the MD) defining the MLC shapes for each gantry angle, and ...


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Percentage Depth Dose Curves (or PDDs) are used to determine how many Monitor Units (MU) a treatment machine needs to give (or how long the machine needs to be on) to deliver a particular dose to a particular depth. The depth at which the PDD curve peaks is referred to as dmax. Treatment machines are often calibrated so that 1MU = 1 cGy at dmax in water. ...


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Sound waves are pressure waves. We measure it as a logarithmic ratio of intensity. Sound intensity is a useful parameter to measure because it's related to the energy incident on a surface which can be easy to measure. Sound intensity is proportional to pressure squared. When calculating decibels we would have to handle that like so: \begin{equation} I = ...


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Let me start off with something that should be obvious but I feel the huge need to say it -- I am not trained in the biomedical field and what I put in my answer should not be construed as definitive and ready-for-use in actual patients. I will do my best and present what I think is correct, but I am not a doctor and don't even pretend to play one on TV. ...



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