Tag Info

Hot answers tagged

10

I have no idea what's the real reason for the survival of the poor fish, but I would guess this is all in the timing. I know for certain ;-) that one can submerge a hand in liquid nitrogen for a short time or in general one can pour liquid nitrogen on the skin with no harm done whatsoever. The reason is that the difference in temperature that interface ...


7

I would draw the line beyond 35, but thats a bit cosmetic. The reasons are manyfold: due to the exponential fashion of the amplification (ideally) reagents are used up at some point reagents degrade, this is especially true for the dNTPs the activity of the enzyme, despite being heat-stable is declining over time beyond 35 cycles the exponential curve is ...


7

When I think about your question of natural examples of XOR, it pushes me to think about what type of natural environments (i.e., evolutionary pressures) would lead to the selection of an XOR equivalent. When we implemented a synthetic XOR by "double flipping" one transcription terminator as a type of gene expression "check valve" it was the case that I ...


5

How many cycles of PCR before dNTPs run out? Assume a 25 μl reaction. Assume 200 μM dNTPs. 200 μM dNTPs = 200 pmol μl -1 so in 25 μl reaction, there are 5000 pmol of dNTPs = 5000 x 10-12 x 6 x 1023 molecules = 3 x 1015 molecules dNTP Assume that we start with 1 molecule of a 1000 bp template, 50% GC 1 kb = 2000 nucleotides So , ...


4

The quote refers to 'robber' bees, but in today's terminology, there are actually three separate phenomena. "Cheating" in bees and other social animals refers to the exploitation of a social contract for one's own benefit. Example: bee workers lay their own eggs rather than tending those of the queen. "Laziness" or "inactivity" of bee or other social insect ...


3

ELISA is Enzyme-Linked ImmunoSorbent Assay (capitalisation to point out source of acronym). You can read about the various ways to do an ELISA here. In your case this was probably an indirect ELISA. All ELISA techniques make use of the fact that proteins stick to plastic. In your case the protein components of the saliva, including the virus (the viral ...


3

Well, without the details of your experiment to cross-check with the sugar and H2O content of your average grape, I'd say the saturated solution probably approximated the natural molarity of sugar in the grape. At least to the point it didn't make any advese effects noticeably on your time scale. That seems the most apparent solution to me. I suppose it's ...


3

At the interface of the stack gel and resolving gel is a pH change and a change in gel density. If you feel certain that your protein is not crosslinking so much that it can not enter the gel than I would think about the pH of the sample and the effect of Cu ions on the stacking effect of the stacingk gel. Is your sample the normal blue color (indication ...


2

I think this would me more on topic at English.SE, but (from Merriam-Webster): Delineate: 1 a : to indicate or represent by drawn or painted lines     b : to mark the outline of 2 : to describe, portray, or set forth with accuracy or in detail — de·lin·ea·tor noun In this case, it could be either meaning that is ...


2

To delineate an experiment is to describe precisely the conditions and the states of all the parameters. So in your sentence it probably means a scientist might struggle to keep track of all the confounding factors (changing salinity, composition, dissolved gases, particulates, pH, temp, etc.) which might affect an experiment in such a dynamic system as the ...


2

It is important to note that osmotic pressure is a colligative property, which means that it does not depend on the identity of the solutes, but simply their concentration. This also means that in considering the grape, we have to estimate the concentration of all solutes, not just the one you used to make the (possibly) hypertonic solution. I'll assume the ...


2

Yes: That GH has an effect on glycaemic control is most evident from the abnormal glucose tolerance seen in acromegalics... acromegaly is defined as abnormal growth of the hands, feet, and face, caused by overproduction of growth hormone by the pituitary gland. Such an effect has been known for decades, which makes sense given how interrelated the ...


2

(Not only) Wikipedia states that in vitro and in vivo have a very hard boundary between them. I something is studied in the context of an organism, without being extracted, it is in vivo, as soon as it is extracted it is in vitro. Strictly speaking, I would count only the first of your neuron examples as in vivo, because it is still expected to be working ...


2

Ex vivo simply means "outside the normal, living organism", whereas in vitro means "within glass", usually in a cultured system. They are not exactly same as there is no need for the work to be done in a culture system, although both are not in vivo. Harvested tissue could be examined ex vivo without being in a test tube, or surgical systems could be ...


1

Yep, the Hough Transform is a way to pick out shapes you're interested in, in this case they probably have it set to find circles, and they use that to segment the image. I think that you have interpreted their methods correctly. For each cell they make a trace of localization score vs. time, localization score defined in arbitrary units as the difference ...


1

The answer is more like "It depends on the protein, and the renaturation (or refolding) process." There are a lot of factors that contribute to an individual protein's ability to refold, including size, sequence, secondary structure, amount and type of inter-amino acid links like disulfide bonds, number of subunits, the presence of chaperones/heat shock ...


1

I think the closest example to this is Greg Lang's work at Princeton. His work will take a population of yeast and let it grow for 1000 generations. At each generation a sample will be kept allowing sequencing of the population at each generation. His website is available here: http://www.genomics.princeton.edu/glang/ And some of his work has already been ...


1

i tried this experiment but failed. The reason for our failure in this experiment might be as follows: 1. The grape coating might be immpermeable. 2. It may happen that the solution might not be hypertonic but isotonic(equal concen. of solutes in both) 3. The salt solution might be less dilute than the sugar one. i am just a student but giving my point of ...


1

Sounds like the copper cross linking the protein or creating aggregates that the SDS buffer can't break up. add EDTA to your loading buffer before you cook it?


1

What do you mean by you couldn't find anything on the internet? Drosophila generation time is explained here? Your other question is a bit off-topic here but I'll give all advice I have heard myself: You can leave out a banana skin and catch some fruit flies, then do the experiment in your kitchen :) Joke aside, unless you perform the experiment ...



Only top voted, non community-wiki answers of a minimum length are eligible