1

Physiology & Medicine / Re: Are stem cell therapies for arthritis safe and effective?

« on: 06/01/2021 10:17:41 »

The stem cells need to come from your own body, otherwise they will be destroyed by your immune system.

There have been some successes in converting one kind of cell into another kind of cell in the lab.
- But doing it reliably is a challenge
- Implanting the cells where wanted needed is somewhat straightforward
- Regenerating the damaged target tissue is another challenge
- At present, few of these myriad options have been submitted to a regulatory authority, let alone approved.

So until a procedure has been tested and approved in clinical trials, it's not worth your money to fly to Thailand, India or Pakistan (even assuming retail air travel resumes sometime in the next year or so)

2

Physiology & Medicine / Re: Can cartilage re-grow in the human body?

« on: 06/01/2021 00:28:10 »

Yes. Spontaneous repair is unlikely because cartilage is used in areas of stress and movement, but you can seed cells onto a "scaffold" which can be implanted into the damaged joint as an active repair.

3

Physiology & Medicine / Re: Which country's covid-19 vaccine would you prefer if several are available?

« on: 04/10/2020 23:21:53 »

Donald Trump has reportedly been treated with a mixture of mono-clonal antibodies (does this make it a "poly-clonal antibody"?). This is Regeneron’s REGN-COV2 formulation. It's too late to give him a vaccine, and the antibodies are probably safer than convalescent plasma.

Notably absent from his treatment is his much-hyped hydroxychloroquine....

a temperature of -70(F or C?) is required to store the synthetic vaccines for up to 1 month.

The "cold chain" of storage for vaccines is critical for vaccines to be effective.

Most vaccine fridges at your doctor or pharmacist are set for around 4C.
- One of the candidate vaccines is proposed to be distributed in "Dry Ice": solid carbon dioxide, at -76C
- Another RNA vaccine is proposed to be distributed in liquid nitrogen, at -196C
- For many remote areas of the world, it is a challenge to maintain 4C throughout the entire distribution chain...
- Another indication that "second generation" vaccines may be more practical than this first generation.
See: https://en.wikipedia.org/wiki/Cold_chain#Uses

egg injections are required to cultivate the vaccine. (I don't know why)

The annual influenza vaccine is grown in chicken eggs - it is a well-practiced way of producing a flu vaccine, as influenza grows well in chicken eggs. The factory processes and equipment are already in place, as is a source of eggs (although it may interfere with production of this year's flu vaccine?)

It's unclear to me whether the coronavirus grows well in chicken eggs - I know coronavirus can infect humans, apes, cats and mink.
- Birds are fairly low in their similarity to human ACE2 receptor
- Perhaps the Chinese manufacturers have genetically engineered the chickens to express the human ACE2 receptor, so the coronavirus can grow better in the eggs? But it will take several years to grow a significant flock of genetically-engineered hens.

See: https://www.medicinenet.com/what_animals_can_get_and_spread_covid-19-news.htm

4

Cells, Microbes & Viruses / Re: What are the best links for up to date COVID-19 statistics?

« on: 03/09/2020 11:32:53 »

The population of Wuhan clearly had more exposure to COVID than anyone else

The Naked Scientists podcast this week spoke to a number of experts about the origins of the novel corona virus.
- Naturally, with limited evidence from the early months of the pandemic, there was a wide range of ideas
- One researcher tracing the family tree of the coronovirus suggested that the "ancestral" viral strain in humans appeared to come from another province, farther south than Wuhan. He suggests that the virus may already have been adapted to humans by the time it reached Wuhan, and started spreading through the fish market.
- Another speaker commented that for previous viruses, people living in close contact with local bats were found to have antibodies to bat viruses, indicating that they had been previously exposed to the virus, but without human-to-human transmission, it wouldn't become an epidemic or pandemic.

Perhaps the UN investigation team can find some more details, assuming that a cover-up hasn't been in full swing for the past 8 months...
See: https://www.thenakedscientists.com/podcasts/naked-scientists-podcast/where-did-covid-come

5

Cells, Microbes & Viruses / Re: What are the best links for up to date COVID-19 statistics?

« on: 27/08/2020 22:33:25 »

why not find a vaccine for a common cold at the same time?

Because the common cold is not a virus.

The common cold is a swarm of over 200 different viruses that surround us humans and live in humans (and sometimes our pets), and have periodic outbreaks when our herd immunity falls, or one of them mutates enough to be unrecognizable. We have several outbreaks every year (more of them in winter).

Around 4 of these 200+ are coronaviruses.

You can see the immense effort put into a vaccine for 1 sometimes-lethal corononavirus.
- Now multiply that by 4 to cover 4 rarely-lethal coronaviruses.
- Now multiply that by 50 or so to cover 200+ rarely-lethal other types of virus
- The combined resources of the world's pharmaceutical companies is not enough to cure the common cold

The COVID-19 vaccine(s), if/when they are approved will have a carefully measured dose, sufficient to trigger a resistance to serious COVID disease, but not enough to trigger a severe immune reaction to the vaccine in the majority of the population.
- But some vaccines may still not be enough to prevent a person getting infecting and shedding a serious amount of virus that could affect others (apparently, the Oxford vaccine is in this category).
- Now dilute that carefully-measured dose of COVID-19 vaccine by 200 to insert vaccines to 200 other "common cold" viruses, and you will have an ineffective vaccine against COVID-19 (and probably ineffective against the other 200 too).

It is enough of an achievement that we can start distributing an effective vaccine against COVID-19 in the next 12 months.

The real bonus will not be vaccines against the common cold, but in development of techniques to produce and test vaccines against the real killers - diseases that have been endemic in some parts of the world for centuries, but which never got much attention because they didn't infect people in the wealthiest nations.

See: https://en.wikipedia.org/wiki/Common_cold
https://en.wikipedia.org/wiki/Neglected_tropical_diseases

The other bonuses may be in the areas of:
- A better public understanding of the scientific method: Some members of the public may understand the difference between "peer reviewed" and a politician making up something during a press conference
- A better understanding that a placebo-controlled study (where there is a 50% chance you will get the medication) is actually more beneficial for the population than an uncontrolled study (where everyone gets an untried medication), and nobody is any wiser at the end.

6

COVID-19 / Re: Are there trial vaccines targeting anything other than the spike protein

« on: 26/08/2020 20:38:23 »

Thaks for that Edwina. I get a little annoyed by articles callig Jenner the father of immuology  vaccination, when doctors had been immunising against smallpox for centuaries in China, India and Africa.

7

Physics, Astronomy & Cosmology / Re: Which forces are directable

« on: 20/08/2020 14:13:55 »

Electric and magnetic fields propagate through space but are difficult to direct over distances greater than the diameter of the source.

Magnetic fields need a return path that doesn't upset other people's computers, but do have the ability to suck some objects.

Gravity sucks radially and not very well.

Electromagnetic radiation of lower frequency than x-rays can be focussed or, particularly in the case of laser radiation, propagated as a parallel beam.   

You can transmit a lot of momentum in a bullet.

Wherever I have to move an object at a distance, my first preference is to use a stick or a string.

8

Chemistry / Re: What are the white rings that form during the Beirut ammonium nitrate explosion?

« on: 06/08/2020 12:18:51 »

The first video had a white spiral BBC logo added at the start.
- But the white clouds behind the shockwave are real in all the videos.

Some other videos I have seen showed a fire in a fireworks warehouse. The people seeing the fireworks seemed to think this was quite entertaining - quite unlike the massive explosion that appeared to be triggered by the fireworks.

Chemists on TV tonight said that you have to get Ammonium Nitrate quite hot before it explodes - so fireworks should probably not be stored next to  Ammonium Nitrate!

9

Chemistry / Re: What are the white rings that form during the Beirut ammonium nitrate explosion?

« on: 06/08/2020 10:30:41 »

Looks like the white rings are added artwork to the video.
This BBC article has the video without the rings at the beginning.
https://www.bbc.co.uk/news/amp/world-middle-east-53656220?__twitter_impression=true

What are you on about?

The clouds are real.
It would be silly to add them.

They are present in all the videos, (about 8 seconds into the 2nd vid, for example) though they are clearer in some than in others.

They form because the air immediately behind the shockwave expands rapidly and cools, causing moisture to condense from the air.
You don't need an explosion to see the effect- it's part of what causes condensation trails behind aircraft.
https://en.wikipedia.org/wiki/Vapor_cone

The explosion is mainly NH4NO3 --> H2O + N2 + O2
 The O2 released reacts with any oxidisable impurities in the material which increases the heat released.
Some NO and NO2 are produced too
NO2 is brown, and you can see that in the cloud.

10

COVID-19 / Re: Could asymptomatic people have invisible organ damage?

« on: 04/08/2020 19:37:57 »

My understanding is that this may be possible. "asymptomatic" unfortunately doesn't strictly mean "no symptoms of the disease occurred," it means "no symptoms of the disease were recognized."

It took many weeks before people realized that "asymptomatic" individuals could be diagnosed by looking for loss of smell/taste, or "covid toes." (new symptoms were discovered)

There are anecdotes of individuals who are (otherwise) "asymptomatic," but developed blot clots, which then caused stroke. So I would imagine that there could be cases of individuals who are infected, don't present the "standard" fever/cough/malaise but could still sustain significant damage to liver or kidneys or what have you...

There is still so much we don't understand about this disease...

11

COVID-19 / Re: Do we know the dosage required to get a COVID infection?

« on: 29/07/2020 16:09:15 »

My hunch is that the prominent 5 day oscillation cycle

What 5 day oscillation?

Have a look at the daily infection graphs on this site. They all display a 5 dayish oscillation cycle.
https://www.worldometers.info/coronavirus/

It's a 7 day cycle, with peaks on Fridays. Most people will work through a low-grade infection and report sick at the end of the working week, with maybe another peak on Monday. Labs may back up their results but post them all on Friday to clear the deck for next week.

The deaths graph is odd, as that also peaks on Friday. Whilst recorded deaths peak on Mondays (because register offices are often closed at the weekend) recorded cause of death seems to peak at the end of the doctors' working week. 

As foir viral load, it's pretty obvious that the more you have, the more likely you are to infect someone else, and the morf you inhale, the more likely it is that some will penetrate your first line of defence and set up shop before the immune system gets into gear. The lack of early symptoms is interesting. It seems as if the innate immune system is very insensitive to the virus, so you can build up an overwhelming viral load before the adaptive system adapts, by which time the innate inflammatory response suddenly turns on as well, producing the excessive inflammation that can become fatal.     

12

COVID-19 / Re: Do we know the dosage required to get a COVID infection?

« on: 27/07/2020 02:26:39 »

https://www.sciencemediacentre.org/expert-reaction-to-questions-about-covid-19-and-viral-load/

13

Physiology & Medicine / Re: What is the best form of calcium supplementation for osteoporosis?

« on: 17/07/2020 21:14:14 »

For each exercise you simply push, pull, lift or whatever against a spring and a strain gauge for about 30 seconds, so the force you exert is up to you and is recorded. The exercises are designed to stress the skeleton rather than work the muscles, hence there is very little movement (around a centimeter or two) or repetition, unlike ordinary weight training. Natural self-competitiveness makes you want to at least repeat and preferably exceed your baseline at each visit, which generally happens, but the real target is to increase bone density, not muscle mass. And it seems to work.

14

Physics, Astronomy & Cosmology / Expansion of the universe - what is being measured?

« on: 17/07/2020 09:05:00 »

I was just reading about the Atacama Cosmology Telescope in Chile. Research is as active as ever in trying to determine the age of the universe and the rate at which the universe is expanding. Does this research measure the rate at which matter is travelling through the universe or measure the actual expansion of the fabric of the universe?

15

Chemistry / Re: What is that liquid in the video?

« on: 06/07/2020 06:10:06 »

Hot grease, it seems.

16

Physiology & Medicine / Re: What is the evidence for scar-healing treatments?

« on: 28/06/2020 09:40:34 »

All silicone products work to reduce the size and overall appearance of the scar. It will often help heal discoloration and the texture of the scar. They contain antioxidants that make the scar heal more effectively. They heal skin by adding moisture, oxygen, and hydration. Sheets work faster because you can leave them on all day under clothing.  Sheets can be worn overnight too.

Silicone sheets reduce redness, and itchiness of the scar. They come in many sizes and can fit almost any size scar. It is the safest method around.  Silicone sheets, tape, and gel are an effective say to heal scars after surgery. How to heal scars is easy with silicone gel products. This is one of the most effective scar treatments with the least side effects. Ask your doctor to recommend a brand like scarheal to aid with your recovery after surgery.

17

Technology / Re: Using ions to electrify space debris to slow down in earth's magnetic field

« on: 14/06/2020 23:38:15 »

Their are currently two competing methods for the clearing of space debris:

a) Physical orbital mitigation  see Clearspace and ESA and other companies.

b) Laser vaporizing of Space debris see Roscosmos. Patents have been filed by this organization with the European Patent Office. 

Professional translators warning:
========================
Great care should be exercised with Russian patents, as they are often poorly translated and claims made are without peer to peer approval.

18

Physics, Astronomy & Cosmology / Re: Is this gyroscopic antigravity?

« on: 01/06/2020 08:24:44 »

Eric Laithwaite was an interesting character. His work on electromagnetic suspension and motor systems was inspirational and timely, and he contributed some great ideas in the aerodynamics of buildings, but his lack of understanding of the conservation of angular momentum was baffling.

Interestingly, Eric Braithwaite also served in the RAF and studied physics, but became a schoolteacher, author and later a lecturer in English, not engineering.

The odd thing is that Laithwaite's RAF career was as a test engineer on autopilots, so he should have understood the theory of gyroscopes pretty well.

19

Physics, Astronomy & Cosmology / Re: Is this gyroscopic antigravity?

« on: 01/06/2020 06:16:37 »

Wiki page on Eric Braithwaite says:
"In his lecture before the Royal Institution he claimed that gyroscopes weigh less when spinning and, to demonstrate this, he showed that he could lift a spinning gyroscope mounted on the end of a rod easily with one hand but could not do so when the gyroscope was not spinning."
"In his 1974 lectures, Laithwaite suggested that Newton's laws of motion could not account for the behaviour of gyroscopes and Laithwaite suggested that they could be used as a means of reactionless propulsion."

The effect is easily demonstrated.  The spinning gyroscope (a wheel at the end of a long axle, lifted by the other end) has only weight, but if not spinning, torque must also be overcome, making it far more difficult to lift despite no difference in weight.  I doubt that a professor has that poor of an understanding of simple gyroscopic effects, so my impression is more of somebody claiming amazing feats to the gullible when it is just ordinary (Newtonian) physics going on.
I think I can find a link to a video of somebody doing this, discussed in another thread.

Not sure if this has anything to do with the OP.  On the ISS, the device would have no weight in the first place and would not precess, and has no concept of being 'lifted'. I don't see any mention of 'jumping' in any descriptions in the searches I ran.

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Physics, Astronomy & Cosmology / Re: Is this gyroscopic antigravity?

« on: 01/06/2020 05:55:38 »

I found an article by NASA speaking about Laithwaite's idea. Scroll down to the section titled "Gyroscopic Antigravity": https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20070004897.pdf

So far, I haven't found any information about a test of such a device aboard the ISS.