Science, Art, Litt, Science based Art & Science Communication
Qs people asked me on science and my replies to them - Part 190
Q: Can we wash our cloth masks and reuse them? How can we wash our cloth masks? Should we use hot water?
Krishna: While removing the cloth masks never touch the front side. Always remove them from the back and wash your hands immediately with soap and water.
If you want to reuse your cloth masks, a standard laundry cycle is enough to wash the coronavirus off cloth, according to the WHO .
Because Corona virus is an enveloped virus, it’s really susceptible to detergents. The envelope that encapsulates viruses like influenza and SARS-CoV-2 is a delicate layer of oily lipids and proteins, held together by surface tension. Laundry detergents and soaps contain surfactants, chemicals that easily break that envelope apart by reducing surface tension.
A surfactant molecule has one end that’s attracted to oil and grease, while the other is attracted to water. The oil-loving end wedges into the coronavirus’s envelope, busting it apart. The remnants get trapped in circular pods of surfactant called micelles and are washed away in water. The interaction of that surfactant with the viral envelope pretty quickly destroys the ability of that virus to be infective. Potent surfactants are found in most home and commercial cleaning products.
The water temperature in the washing machine doesn’t matter as long as you use detergent. The masks made of cotton withstand higher temperatures, so if it makes you feel better to wash it at a higher temp, go ahead and do that. The high, concentrated heat from a dryer offers added protection: it’s enough to kill most microorganisms.
Q: When looking up at a blue sky, many people see tiny dots in their field of vision that follow squiggly lines. What are they?
Q: What are the things we see floating before our eyes?
Krishna: When looking up at a blue sky, many people see tiny dots in their field of vision that follow squiggly lines. These move in sync with our pulse, briefly accelerating with every heartbeat, and they usually disappear after about a second.
The dots are actually white blood cells moving along the fine blood vessels (capillaries) in front of the retina at the back of the eye. This experience is called the ‘blue field entoptic phenomenon’ because it’s especially noticeable when looking into bright blue light, such as a cloudless sky.
Whereas red blood cells absorb blue light, white blood cells do not, so they let the light through to the retina. Light-sensitive cells in the retina read this as a signal of increased brightness, causing us to see the white blood cells as spots.
The "small worms or transparent blobs" are eye floaters or muscae volitantes, Latin for "hovering flies". They might be bits of tissue, red blood cells or clumps of protein all floating in the vitreous humor contained within your eyeball. When the floaters drift close to the back of your eye, they cast a shadow on the retina that you can see against a uniform background.
The second phenomena, "dots of light darting about," is called the blue field entoptic phenomenon because it's easiest to see against a uniform blue field. These lights are caused by white blood cells coursing through the tiny capillaries on the retina’s surface. The cells are nearly the width of those capillaries, so they cause a little bit of a traffic jam, where red blood cells pile up behind them and a clear plasma space builds up in front of them. That clear space lets light pass through and we see a quickly moving dot of white.
Explore the science of the phenomenon of “floaters,” those tiny blobs that swim across your field of vision.
Q: If the chance of recovery from the coronavirus is 97%, why is the world so panicked?
COVID-19 is not just a respiratory disease but an illness that can affect multiple organs
COVID-19 is not just a respiratory disease but an illness that can ...
First thing most people notice is loss of their sense of smell and taste.
Later, respiratory infection that causes fever, aches, tiredness, sore throat, cough and, in more severe cases, shortness of breath and respiratory distress occurs.
We now understand that COVID-19 can also infect cells outside of the respiratory tract and cause a wide range of symptoms from gastrointestinal disease (diarrhoea and nausea), liver disorders, to heart damage ( Coronavirus disease 2019 is associated with a high inflammatory burden that can induce vascular inflammation, myocarditis, and cardiac arrhythmias) and blood clotting disorders , strokes.
Several other unusual symptoms too have been reported. Like the Multi-system inflammatory syndrome, Strokes and blood clots, covid toes, Silent hypoxia, Delirium to name a few.
Renal tropism is also a potential explanation of commonly reported new clinical signs of kidney injury in patients with Covid-19.
Even placentas of pregnant women are showing injuries.
If it is just like flu, you either live or die. That is okay.
But if you have to suffer the consequences of your whole system becoming a mess when you overcome it to tell the story, and if that story is a horror film, and if you have to live with it your whole life, no, we would better not to have it at all.
Okay, only a few will get affected this way. But I don’t know whether we will be one of these few.
It is not panic. It is always wise to think ‘better to be safe than sorry’.
Q: Why do the dead bodies of some yogis not decay even after many days?
Anecdotal evidence of stories people tell can’t stand up to strict scientific scrutiny.
Unless you use some technique to stop the decay, either a natural one or an artificial one, there is no way this can happen.
Miracles that science can’t explain don’t happen now. If you still believe in them you belong to ancient times.
Q: Can asymptomatic people turn symptomatic?
Krishna: There are two terms here: Asymptomatic and presymptomatic.
Asymptomatic means people who have been exposed and infected but never develop symptoms. Presymptomatic describes people who have been exposed to a disease and infected but are not yet showing symptoms.
We know more about presymptomatic patients, in part because they go on to get sick, so they are easier to identify. Covid-19 symptoms, on average, develop around 5 or 6 days after you are infected, although it can take up to 14 days. Some patients also only ever develop very mild symptoms.
Scientists are still just beginning to understand asymptomatic Covid-19 infections. Topol recently published a review of 16 different studies, and the results, published in Annals of Internal Medicine, found that a staggering 40-45 percent of all infections might be asymptomatic. Topol says to separate out presymptomatic from asymptomatic cases, they factored in estimates of the five studies that took multiple PCR tests over time.There were two noteworthy conclusions, Topol explains: One was that you can be infected with, and even have a lung injury from, Covid-19 without knowing it. Two of the studies he reviewed, one in South Korea and one on the Diamond Princess cruise ship, looked at CT scans of lungs and found substantial abnormalities. “That tells you something is going on, even in people who aren’t aware of it,” he says. “It suggests the possibility that you may be asymptomatic and have lingering damage or injury on a chronic basis.” The other was that three separate studies showed the viral load of asymptomatic patients was very similar to those who developed symptoms.
Another study, led by Oyuka Byambasuren, a postdoctoral research fellow at the Institute for Evidence-Based Healthcare at Bond University, used a systematic review and meta-analysis, screening 998 primary studies and preprints to find nine studies from six countries that followed up after an initial positive test to identify who later went on to develop symptoms. Based on this data, Byambasuren estimated an average of 15 percent of Covid-19 cases were truly asymptomatic.
A third study, by Swiss researchers, also found in a systematic review an asymptomatic average of 15 percent, although they reviewed different primary studies than Byambasuren did. (Her team excluded small family clusters that the Swiss study included.) But, the Swiss authors wrote, from their data the proportion of “pre-symptomatic [patients] could not be summarised.”
According to the WHO’s recent update to its guidelines on masks, “the proportion of asymptomatic cases ranged from 6% to 41%, with a pooled estimate of 16 percent.
Asymptomatic patients, since they don’t ever feel sick, can be identified only through PCR tests, which can determine viral load. But this kind of test can only tell if viral particles are present — it doesn’t necessarily mean these asymptomatic patients are infectious.
However, as research is still going on, we can only review the work done so far and say, evidence supports the idea of asymptomatic spread.
Q: How does evaporation cause cooling?Krishna: Another Q from school children? Online classes! Or homework or project work? But please don’t copy this answer as it is. You won’t learn anything that way.
Okay, let us get to the answer.
Liquid evaporating from a surface has a cooling effect. We know this well. Different liquids have this effect to different degrees. Rubbing alcohol has more of an evaporative cooling effect than water. Alcohol evaporates comparatively more quickly than water, so scientists class it as a "volatile" liquid. But regardless of the liquid, they all follow the same principle of evaporative cooling.
Evaporation causes cooling because the process requires heat energy. The energy is taken away by the molecules when they convert from liquid into gas, and this causes cooling on the original surface.
When a liquid evaporates, its molecules convert from the liquid phase to the vapour phase and escape from the surface. Heat drives this process. In order for the molecule to leave the liquid surface and escape as a vapour, it must take heat energy with it. The heat that it takes with it comes from the surface from which it evaporated. Since the molecule is taking heat with it as it’s leaving, this has a cooling effect on the surface left behind. This makes it easy to understand evaporative cooling.
That is how human bodies get cooled too during perspiration. We have pores in our skin from which liquid water internal to our skin is escaping and converting to water vapour in the air. As this happens, it cools down our skin surface. This happens almost constantly to one degree or another. When we are exposed to an environment that is hotter than what is comfortable for us, the degree of perspiration or evaporation increases. And it follows that the cooling effect increases. The more water molecules that are escaping from the liquid phase from our skin surface and from our pores, the more cooling effect there is. Again, this is because the liquid molecules, as they escape and become vapour, require heat and they take it with them. That is how our bodies control heat and protect us from detrimental overheating.
This video explains it well ….
Krishna: “Astrology and horoscopes are real. The characteristics of the signs are fully adapted to people born under a certain sign”.
When you say this, provide evidence. Not anecdotal evidence, but genuine evidence.
Find the difference here: Scientific Evidence
Just silly stories won’t do. Your opinions don’t count in science.
Now ‘Why does science continue to deny the art of horoscope and astrology’?
Because astrology has been proven as pseudo-science! Not once, not twice, several times by several scientists from all over the world.
Find out how here: Why Astrology is pseudo-science
Why do people like you still believe it and fight for this pseudo thing?
Because of Barnum effect or Forer effect
It has also been shown that confirmation bias is a psychological factor that contributes to belief in astrology.
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