Recent comments in /f/askscience

Pablo-on-35-meter t1_j3qde9q wrote

  1. If the iceblock is under water, it is likely that the surface area is reduced. Then, drain. Because you need to maximise the surface area.
  2. Try to keep the meltwater but make sure the water has a big area (large tub), then several things are happening: evaporation of the water results in heat loss. And the bigger area increases the heat transfer.
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Dan13l_N t1_j3qcil0 wrote

Most peoples connected to sea aren't isolated at all, it's much easier to travel over sea than over land. I don't know the precise statistics, I think it's other way round -- morphologically complex and isolated languages tend to be found in mountain areas. I think J. Nichols is the strongest proponent, she has given examples from Caucasus...

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CrambleSquash t1_j3qceft wrote

Why not try it?

I would expect so.

Air is a poor heat conductor and so would do a bad job transferring heat into the frozen cube.

Liquid water on the other hand is quite a good conductor of heat.

If heat can efficiently transfer into the water, e.g. from the container the cube is sat in, I would expect this would increase the melting rate.

The water would also provide an additional surface for the heat from the air to flow into.

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Casperios t1_j3qbwf7 wrote

Well, how i understand it currently, the T-cells need to recognise the antigene or antibody of a virus or cell first to attack them, they can find these antigenes and antibodies themselfs, or they can be presented to them by another cell.

So if the T-cell has a mutation and decides one of your cells antigene means trouble, they will attack. But that is just 1 cell, so it wont cause an autoimmune disease. That can also happen from overpresentation (for example if you have a little to many bacteria in your microbiome), wich is when it CAN cause an autoimmune disease, because its a lot of cells that go against you.

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varialectio t1_j3q8948 wrote

Typically, the formation of esters is an equilibrium process able to proceed in either direction.

Alcohol + Acid <=> Ester + Water

To drive the equilibrium to the right (to make an ester in the lab) it is usually necessary to continually remove the water from the mix as it is created. In the presence of excess water as is going to be the case in the body, the equilibrium is going to be well over on the side of the reactants

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gh333 t1_j3q1tvt wrote

Iceland is also very sea oriented. It was a hub for cod and whale fishing by both Norwegian and Portuguese sailors throughout the middle ages and into the modern period. The major language changes that today make Norwegian and Icelandic mutually unintelligible were mostly complete by the 16th century, which is before the period of intense economic and social decline that Iceland experienced in the 17th century onward due to a combination of Danish economic colonialism, waves of black death, and famines caused by volcanic eruptions. I think it would be difficult to argue that remote Norwegian fjords were more remote than Iceland during this time period, or at least not by much.

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1UpQuark t1_j3pr6nb wrote

Not a lame question at all! It’s astute. Viruses differ in the amount of virions necessary to cause infection because the immune system sometimes does have the ability to fight a particular virus before you get symptoms.

In the case of HIV, HIV positive people on Prep or other drug therapy AND with a very very low titer have been shown to not transmit the virus to intimate partners.

Measles requires a very low amount of virus to cause illness while a fairly large dose of rhinovirus can be handled by the immune system without causing symptoms.

Viruses and our immune systems are fascinating and I could go on all day! Lol

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Jeff-Root t1_j3poyzp wrote

If you look carefully at the ashes from different burned materials, you will see that they are not the same. Ashes of a burned log are quite different from ashes of a burned bone. And even in cases where the ashes look similar, the material that was burned to make them can usually be determined by chemical analysis. Different materials have different proportions of ash-producing elements, so determining the proportions of those elements in the ash can show what material was burned.

-- Jeff, in Minneapolis

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Jeff-Root t1_j3pnife wrote

Ashes cannot be burnt because they are the solid remains of something which was burnt.

Burning something means breaking chemical bonds in a material and forming new bonds with an oxydizer, which most often is oxygen. Some materials burn entirely to gasses and vapors, leaving no ashes behind. For example, hydrogen gas combines with oxygen to form water vapor. Methane and other hydrocarbons, which are composed only of hydrogen and carbon, combine with oxygen to form water vapor and carbon dioxide. Wood, paper, and many other materials contain elements which form solid residues when burned. These elements include silicon, calcium, and iron. Ashes are the portion of a burned material which does not turn into gas or vapor. Ashes typically include oxides of silicon, calcium, and iron.

Most ashes can easily be turned into something else by being eaten. After a forest fire, microbes consume the ashes and turn them into dirt, in which plants grow. Plants absorb the waste products of the microbes in the dirt through their roots, and turn it into new wood, or leaves, or fruit.

-- Jeff, in Minneapolis

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mcrackin15 t1_j3pmf3d wrote

Nothing happens in weather at random, it's s just so complicated it seems that way. Short term weather fluctuations happen and appear to be more random because there's no powerful and sustained force holding it together for a longer period of time. That means different factors are able to enter a particular geographic area and fight with competing forces, often switching it up throughout the week or throughout the day.

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