Questions tagged [medical-devices]
29 questions
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Why do modern MRI scanners use an axial static field?
Last night I was reading some fascinating history of the first full-body MRI scanner and noticed that it's fundamentally different from modern scanners in one particular way: the static B field is vertical, while all the modern machines I've seen…
Bernd Jendrissek
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4
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2 answers
Why automakers are/should be making medical ventilators?
I am not very familiar with the mechanics of neither a car nor a medical ventilator. Considering global coronavirus pandemic and shortage of medical ventilators in many countries, I saw some news suggesting that automakers are starting to…
today
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4
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How does a flexible endoscope turn?
By flexible endoscope I mean colonoscope, gastroscope, etc.
From this video I can see that an endoscope can swivel its tip while in place, kind of like a periscope.
But while moving axially, i.e. "telescoping" (is that the right word?) or "snaking…
6equj5
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3
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Why is the jacket or sheath of fibre optic endoscopes always black?
Why is the jacket or sheath of fibre optic endoscopes always black?
Is it just a convention, or is there a more logical explanation for this?
user3489
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3
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What is the purpose and cause of disposable syringes being single use only?
What's the mechanism behind disposable syringes jamming? How do you prevent this from happening or reverse the effect? They are a lot cheaper.
The problem is that once the syringe is pressed all the way in, the plunger sticks and can not be pulled…
user3421
3
votes
1 answer
Could a medical ultrasound device be used for recording the topography of a small river?
I work as a research assistant in the field of water resources management.
We build small scale physical models of rivers and make experiments with sediment. The model rivers are about 20m long and 3m wide, the water depth is from 0 to half a meter.…
Mathias
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2
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Device like a skateboard for adjusting speed of people who must walk on top of it
Some medication, such as gabapentin, can induce an involuntary and most often unstoppable need to walk; often at determined speeds. This, may be determined by how long someone has taken the medication for and by a given number of mandatory…
Joselin Jocklingson
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2
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Hack a kitchen freezer for lower temperature
Common home freezers usually have the lowest temperatures of about -24 degrees Celsius. Freezers that go lower exist but these are much more expensive (times much). I wonder whether a common kitchen freezer (standalone without fridge) could be…
Kozuch
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2
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How is the first image estimate generated in CT scan iterative reconstruction (IR)?
Background info:
For decades CT scanners produced medical images from x-rays travelling through the tissues of the patient at different angles through analytical methods based on the Radon transform and Fourier slice theorem, and generally falling…
Antoni Parellada
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2
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Positron Emission Tomography: How to get from photon count to radioactivity?
What I have learned
The detectors of the PET actually measure the photons, which are caused by the radioactive tracer injected into the patient. Then, with the help of backprojection, we get the photon count for each voxel. I hope I understood these…
LynxLynx
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IV drip/flow rate controller design
I have a question about intravenous flow rate controllers, which are controlled using microprocessors. For example:
I want to control the IV flow rate, the flow is in range from 0 to 300. So, I just put a number between 0 drips/minute to 300…
rafifadl
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vote
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How was the length of the damper calculated in this figure?
I was reading this research and tried to calculate the length of the damper but couldn't figure out how. tried using the Law of Cosines but ended up with a different result.
Abu Ahmad
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DIY medical oxygen concentrators
Given the dreadful surge of COVID cases in India, with people dying for lack of oxygen, I was wondering if the smart folks here could put our heads together to brainstorm a way to develop a how-to manual on how to cobble up a DIY oxygen concentrator…
Lazarus
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How would an electromagnet function within an MRI?
For the purpose of this situation. Lets say there are 4 small electromagnets within a MRI. All of them activate at the same time. The entire setup is comprised up of non ferrous metals. The metals within the core of each solenoid are only magnetized…
Macus Little
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Why does a shorter strut length result in higher outward force in my heart stent simulation?
I've been working on a simulation of a self-expanding heart stent with the same crown number, ring number, crown radius, etc., but with different strut lengths using Abaqus. The stent is expanded to a 5mm diameter, crimped, and then released to a…
Studio MuKoSe
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