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Question of the Week / Re: QotW - 24.08.09 - Do bacteria in probiotics become part of the microbiome?

« on: 03/08/2024 21:39:02 »

That is the intended plan but how many survive stomach acid and then the various digestive enzymes is the real question. I have seen various reports suggesting that none do and other reports suggesting a significant proportion of viable cells make it to the colon. I have no definitive answer-sorry, but since no other replies were forthcoming I put in my two cents.

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COVID-19 / Re: Was the Covid Pandemic Panic justified?

« on: 01/08/2024 19:02:40 »

Hi BC, I think you have an error: i'm sure you meant to say "the vaccine reduced mortality and infectivity".

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Physiology & Medicine / Re: What Is Junk Food?

« on: 28/06/2024 04:37:17 »

I would also add mechanically recovered "meat" dosed with various chemicals to give it some flavour.

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General Science / somethingRe: What Is Synchronicity?

« on: 23/05/2024 13:20:38 »

When something "appears meaningful" one is dealing with subjective effects as opposed to objective effects. As such no possibility of research into the alleged phenomenon exists. You more or less answered your own question with the reference to Jung's predilection for "magical thinking". In a word , no.

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Plant Sciences, Zoology & Evolution / Re: Do Fish Salivate ?

« on: 17/05/2024 19:49:23 »

Whales being mammals almost certainly do but fish?, I don't know. By a statement in your question we now know that sheep salivate, much as I suspect is the case for all mammals. Then again i'm just a lowly retired engineer, not a biologist and I replied as no one else had and i'm bored. And I enjoy these ovine onslaughts.

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Physiology & Medicine / Re: How Do the Immune Cells Detect The Invading Infection ?

« on: 15/05/2024 08:58:29 »

An addendum re cancer and dna. Dna is generally well sequestered within a cell and is not "visible" to the immune system. What determines the "self" versus "nonself" is the cell surface antigens and sometimes these can reflect changes in dna. Some cancers involve alteration to the cell's dna: the Philadelphia chromosome occurs due to two genes being partially transposed resulting in a new combination, this leads to one of the leukemias . A lot of cancers occur due to the switching off of apoptosis genes. Apoptosis is programmed orderly cell death which may occur due to serious faults within the cell or simply that time has run out for that cell. In the absence of apoptosis rogue cells can multiply and cause chaos.

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Plant Sciences, Zoology & Evolution / Re: What Organisms Have The Most Dissimilar DNA ?

« on: 14/05/2024 19:19:35 »

Indeed Halc, on your last point: there is strong evidence that our mitochondria(which have their own dna) were originally intracellular bacteria of the Ehrlichia species.

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Physiology & Medicine / Re: How Do the Immune Cells Detect The Invading Infection ?

« on: 14/05/2024 18:58:34 »

Cells of the immune system find their target by the process of chemotaxis. This is where the gradient of certain signalling molecules indicates the direction of it's source much like tracing the source of a smell. The processes involved are quite complex involving the placing of markers on the surface of damaged or infected cells followed by complex messaging between macrophages, reticular cells and t lymphocytes. If a cell is infected by a virus, fungus or intracellular bacterium the final stage is the homing in of killer t lymphocytes, via chemotaxis, to destroy said cell. Free floating bacteria are dealt with by neutrophils and I think this is not directed, but I could be wrong.

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Physiology & Medicine / Re: Why Make Scar Tissue Instead Of Bog-standard Tissue To Heal ?

« on: 14/05/2024 16:02:27 »

My knowledge in this area is rudimentary and wooly:  when damage occurs the first responders are cells of the immune system( neutrophils, macrophages, lymphocytes etc) to deal with any microbiologic intruders and these are followed by fibroblasts. Fibroblasts are immature fibrin producing cells which lay down a mechanical barrier to seal the area- otherwise consequences would be devastating with the amount of hostile agents in the environment. To replace identical tissue  new cells of the correct type would have to generated by mitosis of competent progenitor cells and would take too long, the fibroblasts are much faster.   

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Physics, Astronomy & Cosmology / Re: Observing Quantum Entangled particles At the Same Time . What Happens ?

« on: 13/05/2024 19:10:18 »

To solve that conundrum we have invoke the Lamb shift!!  sorry Neilep, I couldn't resist, I have no clue as to the answer as it is well above my pay grade.

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Physics, Astronomy & Cosmology / Re: Why didn't the total solar eclipse strain my naked eyes at all?

« on: 09/04/2024 13:50:30 »

Looking directly at the sun is inherently hazardous and something one should never do. Just because it did not hurt does not imply it was safe to do so. I am sure you have seen the effect of direct sunlight through a lens setting fire to a piece of paper- now consider the same effect directed at the fragile retina at the back of your eye. Damage may have been done only to show later.

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Physics, Astronomy & Cosmology / Re: Does time dilation and length contraction apply to light?

« on: 07/04/2024 10:38:10 »

Krytptid's thoughts here mirror mine very closely and it seems I have a major gap in my understanding of SR(not surprising really). If one could travel at the speed of light surely one's rapidity would be infinite and hence time and space would have no existence- why does this not apply to light?. I have heard several physicists state that "light does not experience time or space" or something similar expressed more accurately: I cannot remember any names other than the mathematician Roger Penrose(who can be controversial at times). This question of mine is a bit muddled but I could not find a better wording. 

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General Science / Re: Is Absolute Zero Possible?

« on: 04/04/2024 20:38:17 »

Just the same as trying to accelerate a massive object to the speed of light, we can get arbitrarily close by expending more and more energy but we can never get to the target speed. Similarly with absolute zero the closer one gets the harder it becomes to produce a further decrease. Mathematically one can only asymptotically approach either the speed of light(with mass) or absolute zero. |Oh dear Eternal Student beat me to it!

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New Theories / Re: Could quantum mechanics be wrong?

« on: 18/03/2024 09:27:20 »

"Could quantum theory be wrong?", yes of course it could be wrong, as could any theory. However quantum theory has been stunningly successful in explaining observations and making predictions and to debunk it would require a better theory and I see nothing on the horizon. Quantum theory is counterintuitive and baffling but that in itself does not make it wrong.

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Physics, Astronomy & Cosmology / Re: Gas discharge tube hydrogen

« on: 17/03/2024 22:12:33 »

Hi ES, I would have said 1Mv/m for normal air but I could be wrong. Many discharge tube use additional methods to start the initial ionisation, prior to avalanche occurring such as heated filaments in florescent lamps, a high voltage external conductor in xenon flash tubes and an auxillary electrode very close to one of the main electrodes in mercury vapour lamps(to start a local ionisation). High pressure sodium lamps and tin halide lamps use a high voltage source in series with one of the electrode supplies. The gas pressure plays a major role in the voltage needed to initiate ionisation, referred to as the strike voltage: the higher the pressure, the higher the necessary voltage and a lot of discharge lamps have to cool down after power interruption before reuse as the pressure is higher when hot. Many other factors may account for the discrepancies in the calculations: random cosmic rays as you suggested or low level radionuclides. Field emission as raised by Alancalverd may play a role(wild assed guess).   

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Physics, Astronomy & Cosmology / Re: How many spots are produced from Stern-Gerlach apparatus that rotates?

« on: 16/03/2024 13:49:27 »

I remember this experiment from my long distant college days but I had forgotten it's name. I can't add anything of value, I do however have a question: how are the silver atoms entrained in a beam? the only way I can think of is electrostatic acceleration, that would lead to charged particles which are ruled out by the terms of the experiment.

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Physics, Astronomy & Cosmology / Re: What is the Hopf gauge?

« on: 11/03/2024 22:11:16 »

I managed the rubik cube ONCE, but could never repeat it.

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That CAN'T be true! / Re: Is HCQ the antidote to Trump?

« on: 11/03/2024 22:04:04 »

It is likely that improvements in genetics will in the future allow a prescriber to know which medications will have the most beneficial effects and the minimum of side effects--the so called "personalised medicine". We are not there yet. As regards hydroxychloroquine the eye damage is a direct effect of the medication on SOME people and it has nothing to do with covid. All medications for autoimmune conditions have serious and sometimes severe(including lethal) side effects. Quite apart from this any drug, even the humble aspirin, can have unexpected dire effects. I know a person who having taken an aspirin developed an anaphylactic reaction and whose life was saved by a local doctor who happened to be at home at the time.

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New Theories / Re: What caused inflation?

« on: 28/02/2024 19:06:29 »

"What caused inflation?" Bad monetary policy obviously (sorry!!)

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Just Chat! / Re: What is the difference between Beer, Lager and Ale?

« on: 27/02/2024 09:14:34 »

You are all forgetting porter, the black stuff, as in Guinness. The colour, as far as I know, comes from a large quantity of malt used in manufacture. Beer is my favourite drink although I rarely exceed two drinks these days as opposed to my misspent youth when I drank all alcoholic drinks to excess.