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The U.S. Food and Drug Administration (FDA) has the following information regarding the risks of ultrasound imaging; Ultrasound imaging has been used for over 20 years and has an excellent safety record. It is non-ionizing radiation, so it does not have the same risks as x-rays or other types of ionizing radiation. Even though there are no known ...


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Technically, higher main magnetic field strength doesn't mean more resolution. There are three parts to the scanner: 1) main magnetic field, 2) gradient coils and 3) RF coils. The main magnetic field strength (1.5T, 3T, 7T, 9T, the last two typically more for research) determine more of the signal to noise (in a very simple sense). This is static - it ...


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No, one can't confirm age by carbon dating. That doesn't mean we can't make a decent guess by other methods. There is an interesting case of a 33 year old Texas woman who enrolled in 10th grade in Texas. She said she had no transcripts because she had been homeschooled. She looked like a teenager and acted like a one too. She even fooled her new 23 year old ...


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As Luke points out, the ultrasound is very safe. However, in many cases it is not required. Typically by 20 weeks into the pregnancy, and sometimes earlier, a baby's sex can be determined by examining the genitals via ultrasound. My experience is that this is the most common reason for an ultrasound during pregnancy. Of course if there are complications ...


3

Short answer The units aren't important, and are typically normalized. Longer answer The name "BOLD" is actually very instructive: Blood Oxygenation Level Dependent contrast (or signal). BOLD is not directly measuring anything like oxygenated/deoxygenated ratio, or we would probably call it something more similar to that: oxy/deoxy ratio. Instead, "BOLD" ...


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I do not think that a publication quality blot should have such an artifact, but I was able to find something similar by purposely over blotting (not the same as over exposing) a gel. If you use too much primary, secondary, or developing reagent, you can get your HRP signal to "burn in" a membrane where you get a distinct "negative band." By negative ...


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ImageJ is a multi platform piece of software that has a cell counter module that might be of some use, and hey its free! Its easy to use and so ludicrously crude that it is very versatile. I remember using it in undergrad to count cells under the microscope automatically after a few image contrast tweaks. I don't see why this couldn't be reapplied to count ...


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There is a lot of variation in how and when deer shed their antlers. In most arctic and temperate-zone species, antler growth and shedding is annual, and is controlled by the length of daylight. In tropical species, antlers may be shed at any time of year, and in some species such as the sambar, antlers last several years. Some equatorial deer never shed ...


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To grab this opportunity to sum up the comments for the C-14 dating method, including those of of @MattDMo and @canadier: Theoretically spoken - Yes we can! But only after (1) killing the person and (2) waiting a few hundred years. As carbon keeps on being recycled in a living carbon-based organism, it has to be dead first. Secondly, because the margin or ...


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I'm not familiar with the technique, it is as I'm sure you already know very specialised and I've found it fairly difficult to find resources specific to cine-MRI. At a glance at the wikipedia entry, however, there are a few differences that I can point out to you. A normal MRI will take a snapshot image of a section of the body in time, therefore can not ...


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You definitely need to have the same threshold for both images because you want to make comparison between them. Do you have a control condition (the condition which is not supposed to uptake EdU)? if yes, then use it to set your threshold and keep the same threshold for the tests conditions. If not, you can either make a experiment control, or select a ...


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You need to normalize both images to the background. This can be done in many softwares including photoshop. When I was learning this starting to do it with something more simple like SDS page protein bands helped me a lot. The principles are the same you are still subtracting background. Look at this tutorial: http://m.youtube.com/watch?v=JlR5v-DsTds ...


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Most microscope software provides options for line average or line integrate as a function that helps the signal to noise ratio when taking an image. Averaging sums the lines and then divides by the average number. Integration sums the lines without dividing. They're functionally the same thing just with different scales. I assume it involves summing ...


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is there limit of human body of how much strong magnetic fields it can handle safely which means there is limit to how strong MRI magnets we can use? The 2018 {1} study concluded: Where feasible, effects are quantified for magnetic fields beyond 7T with the conclusion that there are no foreseen barriers either in the technical or human safety aspects of ...


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If I recall correctly, in BOLD fMRI an echo-planar imaging (EPI) sequence is typically used. In one example: 44 slices were acquired, every 3 seconds, 96 times in a row, leading to a total number of 4,224 images acquired in 4 minutes and 48 seconds. — https://www.imagilys.com/functional-MRI-fMRI/ You can read more about EPI here. I think you will ...


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I could have found this article earlier, but as things go, I didn't. But possibly it contains most of what can be said to this question: Jonathan E. Peellej, Methodological challenges and solutions in auditory functional magnetic resonance imaging, Front Neurosci. 2014; 8: 253


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Systematic sampling refers to a method where all samples have an equal probability of being chosen but the spacing between samples is constant. That is, although each individual section is equally likely to be chosen, the combination of samples is not. The Wikipedia article on systematic sampling provides a good overview. Stereology refers to the analysis ...


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One approach: fit a kernel density estimator to the observed coordinates $\{ (X_i,Y_i,Z_i) \}$ and color by density: https://stackoverflow.com/questions/25286811/how-to-plot-a-3d-density-map-in-python-with-matplotlib/25354417#25354417 Incorporating the weights $w$ of each observation is a bit trickier, but there's code to do this: https://stackoverflow.com/...


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R packages misc3d and rgl. The function image3d in misc3d does what you need and is very parametrizable via rgl (change the transparency, the view angle, axes, etc...). I used it with fairly big arrays (~10000000 data points/plots) and it produced great 3D density plots. Both R (e.g. package biOps) and Matlab (image processing toolbox) have very powerful ...


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The Open Source Computer Vision library OpenCV is pretty popular. I'm a Python guy, but it also has C, C++, and Java interfaces. The O'Reilly book Programming Computer Vision with Python was pretty good, and their C-oriented Learning OpenCV from 2008 is coming out with a new C++ edition in July, supposedly. There are also the OpenCV online docs, linking to ...


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Here's an example of a chemiluminescent blot: For those who care, the first column on the left is the weight standard, the next two are pooled pellets, and the rest are increasing fractions of purified HIV using a mouse monoclonal anti-p24 (capsid) antibody. This blot is pretty clean (although for my work it was pretty disappointing...) but here's one that ...


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Coronary artery disease thickens the wall. Flow is dramatically affected by thickness (radius to the fourth power). In an echo you observe the heart muscle i.e. does it contract normally using the surrounding muscle and baseline as a comparison. If the wall is thickened, this will cause a decrease in perfusion which will result in the heart muscle ...


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No, echocardiography is not sensitive enough to do so. For tracing coronary arteries directly flow angiography is the choice.


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Coomassie blue fluoresces in infrared when bound to protein, so if your reader has the appropriate filter set, it should be possible.


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