Jump to content

Danijel Gorupec

Senior Members
  • Posts

  • Joined

  • Last visited

  • Days Won


Danijel Gorupec last won the day on July 19 2020

Danijel Gorupec had the most liked content!

Contact Methods

  • Website URL

Recent Profile Visitors

The recent visitors block is disabled and is not being shown to other users.

Danijel Gorupec's Achievements


Molecule (6/13)



  1. To prepare bread dough, I mix flour and water. They say that water hydrates starch and protein molecules in the dough... What this 'hydrating' mean at the molecular level? I am imagining that water molecules make short-lived bounds with large dough molecules (carbohydrates and proteins). If so, does it mean that those bounds (between water and large molecules) are stronger and longer-lived than bounds between water molecules themselves? What is the thickness of this bound water layer - is it one molecule thick? There is also free (unbound / bulk) water in the dough. I imagine there is some sort of equilibrium between bound and unbound water - that is, you cannot have a dough that only has bound (and zero unbound) water? Still, I imagine that in drier doughs, larger proportion of water is bound and smaller proportion is free? Yeast needs water - I guess it lives inside water - is this the free (unbound) water where the yeast lives in? Btw, I am interested in all things dough, so if you have anything else interesting/important to mention, go ahead.
  2. The derivation you are mentioning... is it considering some sort of plane gravitational waves, or more general? As I understand you, you are also talking about near-observer perturbations? Otoh, the array of clocks, I was mentioning, is distributed.
  3. I was indeed interested in weak gravitational waves... I would be surprised if the theory only predicts disturbances in spatial dimensions, and not the time dimension. Because I am under impression that the theory treats space and time on more or leas equal footing. Anyway, I am now thinking about what you said, if gravitational waves indeed can cause only (or predominantly) spatial disturbance, can then there exist a different type of gravitational wave that only (or predominantly) causes time disturbance? @swansont Thinks for the link.
  4. As a gravitational wave passes though a constellation of precise clocks, would it be possible, at least in theory, to detect its passage by measuring time difference between clocks? If so, is it harder to make such measurements than to measure spatial distortions?
  5. Could two or more space shuttles do it - by refueling in the orbit? At least an one-way trip... You park one shuttle in the orbit, and then use other(s) to bring more fuel.
  6. Does it mean they are using gamma ray lasers? Can you see anything in gamma light without destroying it?
  7. If I understand the task correctly... it is to estimate the moon distance on that exact day (it should be somewhere between 362600 and 405400km). You can take the moon and sun diameter (both fixed) from any external source.... The interesting part, imo, would be to estimate the error of your calculation.
  8. I suppose your relative is aware that it is very easy to check if he sourced the answer from the internet. So, he probably did not have an intention to fool you... I guess he would change the wording if he really wanted to deceive.
  9. Did you watch as it was happening? Was it fast or slow? I recently saw a video of some kind of sea slug catching a sleeping fish... by very slowly enveloping the fish in some sort of extendible bag... I was very impressed, but forgot to remember the slug name to learn more about it.
  10. Hmm... I was supposing that 'not even light' is simply used to explain why it is called a 'black' hole. Most of the time, however, I guess, the phrase is just repeated without much thinking.... maybe we should not overthink it either.
  11. Afaik, the one way will aid to directional stability, the other one will hinder it. When ribs push the mud outward, it aids the directional stability (that is, forces try to straighten the tire path). Normally, on a tractor, you mount the tires to push the mud outward if tires start slipping while the tractor is pulling forward. [But, I guess, if you use the tractor to brake a pushing cargo, such normal rib alignment might make your steering more difficult.]
  12. Hmm... searching further, I found the following quote on Wikipedia: "The larger basal cell will give rise to the suspensor, which connects the embryo to the endosperm so that nutrients can pass between them." ( https://en.wikipedia.org/wiki/Embryo ) "suspensor" seems to be a term, so I found several links explaining it in some details (googled for 'seed suspensor'). Two of them are listed below: https://research.mcdb.ucla.edu/Goldberg/research/Pdf/sdarticle.pdf https://en.wikipedia.org/wiki/Suspensor Quote form the first link: "For example, the suspensor pushes the embryo proper into the endosperm cavity and connects the embryo proper to surrounding maternal and endosperm tissues - serving as a conduit for nutrients and growth regulators required for embryonic development" It seems, the 'suspensor' might have an active transmission mechanism, but the nature of it may not be known yet. However I am not sure if 'suspensor' is really the answer to my question because: the 'suspensor' seems to only exist for a very short period during the very first phase of embryo growth - I am not sure if all the nutrients from the endosperm are absorbed during that time. The 'suspensor' might only consist of a few cells. Subcellular outgrowths might have a role in absorbing nutrients (if I understood correctly). I also guess, something there, 'suspensor' perhaps, should release enzymes to cut the starch into simple sugars. For my second question, I didn't find a valid answer - from the internet readings, I cannot deduce if plant root can absorb glucose or not. I also cannot find any info if plant roots can emit enzymes to transform starch into simple (absorbable) sugars. However, when I think about it, I would guess the answer is NOT - if plants would be able to absorb starch through their roots, I would expect to see more 'predatory' behavior among plants. Anyway, I am abandoning this investigation as it seems to require a knowledge well beyond my level.
  13. I would expect more likely for such a sub to surface than not. Hull implosion seems to me like (it should be) the least expected fault.... In fact, I considered the underwater search like some sort of wasting resources that could be used for the surface search. That said, I am unpleasantly surprised that the sub did not have any orange-colored part. Cannot think of any reasonable explanation.
  14. When a plant seed germinates, how exactly does a germ access nutrients from the endosperm? Does it grow like a tiny roots into the endosperm? Can plant roots absorb starch (or at least break the starch into sugars before absorbing)? For example, if I mix wheat flour into ground and then seed wheat there, will this wheat be able to access nutrients from the flour?
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.