What makes a popping sound when we crack our knuckles?

After completing a tough task many people show their exhaustion by bending their fingers and producing that popping sound. Some people do it out of boredom and some do it for fun.  But what is it that produces this sound? Many theories have been given like rapid stretching of ligaments and intra-articular adhesion being broken, but the theory of cavitation is most plausible.

Joint anatomy- Our joints consists of two bones coming together without touching. If the bones touched then they would grind against each other with time. Our bones are covered by articular cartilage and the space between joints are filled with synovial fluid. This fluid acts as a lubricant and is produced by synovial membranes. The synovial fluid consists of many dissolved gases, mostly oxygen and carbon dioxide. These gases play an important role in knuckle cracking.

Illustration from Anatomy & Physiology, Connexions Web site. http://cnx.org/content/col11496/1.6/, Jun 19, 2013.

Cavitation- To produce that popping sound, we stretch the joints. This stretching moves the bones away from each other, increasing space between them but the amount of synovial fluid remains the same. Now, by  increasing the volume, the pressure is reduced and this reduces the solubility of gases. This is the same thing which happens when you open a soda bottle and dissolved carbon dioxide fizzes out because of fall in pressure. But inside a joint, dissolved gases can not escape the joint and hence form a bubble. This formation of bubble produces that popping sound which you hear while cracking knuckles. Some scientists believe that there might be actually two sounds, one when a bubble is formed and another when it bursts. It takes about twenty to thirty minutes for the gases to dissolve back in the fluid. This is the reason why you can not pop the same joint again for some time.

 Is cracking knuckles harmful?- Some people believe that cracking knuckles repeatedly leads to arthritis but there is not a lot of scientific data available on the topic. One study found no such relation between knuckle cracking and arthritis. According to another study, repeated knuckle cracking may affect soft tissues surrounding the joint. In 2009, a doctor named Donald Unger received Ig Noble prize for conducting an experiment on this subject.  The Ig Noble prize honours research that makes people laugh and then think. He popped the knuckles of his left hand, but not the right hand, for sixty years. His left hand did not develop any issue.

So, next time you pop your knuckles, remember that, it is possible because of dissolved gases in your synovial fluid which is playing this sound at your command. We know now that whether you are popping a bubble wrap for time pass or popping your knuckles, both have one thing in common, the bubbles. 

References-
http://health.howstuffworks.com/human-body/systems/musculoskeletal/question437.htm
http://www.scientificamerican.com/article/what-makes-the-sound-when/
http://www.livescience.com/9729-knuckle-cracking-ig-nobel-prize.html
https://en.wikipedia.org/wiki/Cracking_joints

Do plants feel pain?

Have you ever been pricked by a thorny plant while strolling in a garden? You would have certainly disliked it as it is a painful experience. But have you ever wondered if plants could also be feeling pain? Humans, in general, are against causing any pain to other humans. We also have strong laws against it. We also talk about not causing pain to other animals and it is good that things like animal rights do exist. But we never talk about the pain of trees. The reason being that we can relate to the pain of other humans and animals but not to the pain of plants. We can feel pain, so we empathise with those who can also feel pain the way we feel it, be it humans or other animals. We don't think this way about plants, possibly because may be their body structure is entirely different from ours. We forget that they also have a DNA (humans share fifty percent of their DNA with bananas). We still refuse to empathise with them and ignore that their pain might be having a different manifestation. But why do we reject this idea of plants having feelings and overlook this possibility?

Absence of nervous system- It is argued that plants are not intelligent enough to sense pain as they do not have a nervous system. This point is valid if we assume that a neural network is the only sign of intelligence and feelings in nature. But there are many areas in which plants show amazing intelligence. 

Intelligence in plants- The smartness of plants is reflected by many things. One of them is their ability to communicate with each other. Most of us enjoy the smell of freshly cut grass in summers. That smell is actually a chemical distress call by grass. Different scents are given out by plants for different types of threats. For example, when there is a threat from caterpillars, a scent is given out which makes neighbouring plants to become bitter and this bitter taste is disliked by caterpillars. Also, when a plant senses that it is under attack, it tries to attract other helpful creatures which might kill attackers. Plants can also communicate through roots (like the movie Avatar) and pass useful information about diseases to their neighbouring plants. And, plants like dodder can locate and move towards their host. Intelligence of plants is also proven by the fact that they can sense gravity and light and then grow accordingly (check out this link).

Finding feelings - An Indian scientist J C Bose (one of the fathers of  radio science), conducted experiments on plant perception in 1900. He found plants responded to a shock by spasms just like animals.  He demonstrated the electrical nature of conduction of stimuli like wounds and cuts in plants which were earlier thought to be of chemical nature. He also claimed that plants have feelings by observing the variation in cell membrane potential under various circumstances.

    

 According to researchers at University of Bonn, plants cry and signal it by releasing gases. By using a highly sensitive microphone, scientists have observed sound waves produced by plants releasing gases when injured. Cucumbers have been sensed screaming when sick and flowers crying when their leaves are cut. But at the same time, many experiments have shown no such emotions in plants.

So, we can not exactly say whether plants have feelings or not as there are no concrete results and scientific consensus is missing. But then, we also do not exactly know so many things about working of plants. We can neither accept nor reject the idea of plants having emotions. Plants are obviously not like a piece of rock. They are surely much smarter and can sense their environment. We know now that plants might be feeling pain even without a brain.

References-
http://science.howstuffworks.com/life/botany/plants-feel-pain.htm
https://en.wikipedia.org/wiki/Plant_perception_%28paranormal%29
https://en.wikipedia.org/wiki/Jagadish_Chandra_Bose
http://www.mirror.co.uk/news/weird-news/humans-share-50-dna-bananas-2482139

Death of Bees and future of crops- An extinction we cannot afford

To Bee, or not to Bee, that is the question. According to a report published by a UN body on biodiversity, the population of pollinators like bees, birds, beetles, butterflies and other species is on a steady decline and this poses a serious threat to the food crop production of the world. In recent years, bee keepers around the world have witnessed 30% to 90% loss of colonies. About one third of food crops are pollinated by bees and other small animals. So, losing these pollinators also means losing many of the food items that we consume regularly which include apples, mangoes, rice, wheat etc. Although, I do not want to put a money tag on this loss and death of bees is itself a depressing issue, but since some people understand things only in terms of money, it is estimated that the loss to crops could be from $235 to $577 billion annually. Since, most wild flowering plants(about 90%) depend upon animal pollination, they are under greater risk. I will focus more on bees here but it does not mean that other pollinators are not important.

Colony collapse disorder- It occurs when majority of worker bees in a colony disappear leaving behind queen, food, few nurse bees and other baby bees. It has affected many parts of the world in the last decade. Many European countries have reported greater than 30% decline in bee hives. In 2012-13, colony collapse disorder was held responsible for the loss of half of the honey bee hives in US. But what is the reason behind this decline in population of bees? The answer is that we are not entirely sure but let us explore many possible causes.

Parasites- Acarapis Woodi is a microscopic mite which infects the breathing tubes of bees and weakens them by feeding on them from inside. Varroa Destructor is also a type of mite and is even more dangerous. These mites lay eggs on larvae of bees and they keep feeding on the larvae. The bee larvae is not killed but weakened . When it comes out of the cell, the mites are spread to neighboring cells, thus spreading infection. This cycle is completed in ten days and they grow rapidly, ultimately causing collapse of colony. These mites also spread many viruses that harm bees. But these parasites can not alone explain this steady decline.

Pesticides- The most widely used insecticides in the world today are neonicotinoids. These are neuro-active insecticides which means that they kill insects by harming their nervous systems or their ability to sense world. It can be called as the most inhuman way of killing anyone. In high doses, it leads to convulsions, paralysis and death. In small doses, it causes bees to lose their navigation ability, they forget their way to hives, get separated from the colony and eventually meet a lonely death. Contrary to my earlier position, I would love to put a money tag here. Global sales of nicotinoids was worth $1.6 billion in 2008. With so much money involved, the horrible effects of these insecticides are being constantly ignored.

Other possible causes- In addition to the above possible reasons, things like loss of habitat, climate change, pollution, other human activities etc. are also causing damage to bees and other pollinators. If we want to keep enjoying our plates full of various delicacies and if we want to let our future generations also experience that buzz sound in the gardens, we must protect these little pollinators. Currently, their colonies look much wiser than human colonies.

We know now that when it comes to saving bees, to Bee is always better than not to Bee.

References-
http://edition.cnn.com/2016/02/26/world/un-bees-and-butterflies-report/index.html
http://www.theguardian.com/environment/2016/feb/26/decline-of-bees-poses-potential-risks-to-major-crops-says-un
http://www.onegreenplanet.org/animalsandnature/why-bees-are-important-to-our-planet/
https://en.wikipedia.org/wiki/Colony_collapse_disorder
 https://www.youtube.com/watch?v=GqA42M4RtxE
https://en.wikipedia.org/wiki/Neonicotinoid

How do plants know in which direction to grow? Plants are very smart.

You reap what you sow but seeds that you sow somehow tend to know that they have to send roots downwards and stems upwards. It does not matter in what position you sow seeds, they always grow the right way. How does a seed know which direction is right? From where does a small seed get all this intelligence?  This question intrigued scientists for a long time.

The mystery- Suppose you have a seedling in a pot and you turn it upside down, then the stem will take a U-turn and start growing in upward direction against the gravity. So, the stems always grow in a direction opposite to gravity and roots always grow in the direction of gravity. In short, plants can sense gravity.  In another experiment, a bunch of seedlings were attached to a disc and the disc was rotated at high speed. This rotating disc made seedlings feel a continuous centrifugal force radially outwards from the disc. Such a force can be called as simulated gravity. After continuous rotation, it was observed that plants responded to simulated gravity and their stems grew towards the center of the disc and roots outwards. Also, when seedlings were grown in space where there is almost no gravity, the roots grew in all the directions without any pattern. All these experiments proved that plants can sense gravitational pull. This phenomenon is known as gravitropism.

 Gravitropism- Growth movement by a plant or fungus in response to gravity is known as gravitoprism.Most evidences support that growth in response to gravity is due to regulated movement of plant hormone called auxin. Now the next question is what causes this regulation of auxin in accordance with gravity? This is where statoliths come into picture.

Statoliths- These are parts of a special subset of cells present in the root tips. These statoliths are dense and can sediment according to the direction of gravity. This sedimentation transmits a signal which leads to reorientation of auxin efflux carriers and subsequent redistribution of auxin in the root. And this change in concentration of auxin causes roots to grow in the direction of gravity. Similarly, statoliths are also found in stems and guide their growth in direction opposite to gravity. But gravity is not the only thing which affects the direction of plant growth.

Phototropism- It is the growth of an organism according to a light stimulus. It can cause a plant to grow towards light (positive phototropism) or it may cause growth away from light (negative phototropism). Here also auxin plays an important rule by changing the growth of cells according to light stimulus.

So, a tiny seed not only contains a life in an embryonic form but we know now that it also knows how to reach out for the sky but keeping feet on the ground.

References-
http://www.npr.org/sections/krulwich/2012/06/21/155508849/how-do-plants-know-which-way-is-up-and-which-way-is-down
http://blogs.scientificamerican.com/artful-amoeba/roots-down-shoots-up-but-how-does-a-plant-know-which-is-which/
https://en.wikipedia.org/wiki/Gravitropism
https://en.wikipedia.org/wiki/Phototropism

V know now gets Liebsters

It is a great pleasure to announce that I have received Liebster Award. It is an award given to new bloggers by other bloggers. I was nominated by Kayla from lacesuperheroeslife 
It is so nice of her and I am really thankful to her.

The rules of this award are very simple-
1. First, you have to show recognition for the person who nominated you (that person surely deserves it)
2. On nomination, the person will give you a list of 11 questions and you have to answer these questions in your post.
3.You need to tell your readers about yourself by giving 11 random facts about yourself.
4. You have to find 11 new blogs which deserve the nomination for Liebster award.
5. And lastly, you have to give your nominees a list of 11 questions to answer on their blog.


So, my answers to the questions asked are -
1.What is the most exciting thing you have ever done?
Ans-Riding a tractor on sand dunes.
2. What is your favorite restaurant?
Ans-I love eating at traditional Indian Dhabas (roadside restaurants). I particularly like the ones at Murthal near Delhi.
3.   If you could re-do your high school years over again, would you?
Ans- Yes, I would and I will study only what I like and leave rest.
4.Who inspired you to start your blog?
Ans-Michael Stevens from YouTube channel Vsauce.
5. What is your all time favorite TV show?
Ans-The Big Bang Theory
6. What has been your most rewarding accomplishment?
Ans- Being able to understand at least few things in this vast ocean of science.
7. If you could have a conversation with any person, living or dead, who would it be?
Ans- Albert Einstein
8. What is your lifetime goal?
Ans- To contribute something good in the field of science
9. If you had one million dollars, but could only buy one type of thing with it…what would you buy?
Ans-I would buy lots of tablets with educational stuff stored in them and then distribute them among not so fortunate kids.
10. Who is your favorite author or poet?
Ans-Dan Brown
11. What is your biggest fear?
Ans -Nothing. By nothing I mean having nothing to do. Being bored to death is what I fear.

11 random facts about me

1. I am an engineer
2. I am a very curious person
3. I am also an amateur cartoonist
4. I like programming.
5. I have spent most of the time of my life in Delhi.
6. I like to try different kinds of food items.
7. I love watching YouTube Science related channels.
8. I like playing table tennis and cricket.
9. I prefer tea over coffee.
10. Cooking is a stress buster for me.
11. I love nature.

My nominations are-

1.  Naztrends
2.  Delhifoodieblogger
3.  Tipsfornewbloggers
4.  Georgeforaday
5.  Alfalifestyleblog
6.  Unlockedsuccess
7.  Templatesgeek
8. Falution
9.  Thecolourclub
10.  Footloosedev
11.  Myanomaly

My questions areas as follows-
1. Is your hobby also your career? If not, would you like to make it that way?
2. Given a chance, what would you like to change about this world?
3. Do you have any superstition? If yes, what is it?
4. What inspired you to write this blog?
5. If you could time travel but only once without being able to return, which time would you like to go to?
6. Which super power would you like to have?
7. Which is your favorite means of transportation?
8. Which is your favorite movie?
9.  If you had an option to take over a company and become its head, which company would it be?
10. Which is your dream destination?
11. In your opinion, what is your biggest achievement?

Thanks all.

Are you really you?

Who am I? Have a you ever read a spiritual article and come across this question. But don't worry, I am not going to talk about your soul and spirituality. But still, I wish to ask you this question. What would be your answer when asked - who are you? Some of us will say their names and some will talk about their other credentials. But what makes you different from other animals? Some will say that "I am a human". But are we really humans? Let's see why we can't technically call ourselves humans.

Microbial world in you- A human body consists of many different types of bacteria and their population outnumbers the human cells. According to earlier estimates, microbes outnumber human cells in the ratio of 10 to1. However, this figure has been revised recently in favor of human cells but still the ratio stands at 1.3 to1. A standard man who weighs 70 kilograms, 20 to 30 years old and 1.7 m tall, consists of on an average about 30 trillion human cells and  40 trillion bacteria. The number of different species in human gut lies somewhere between 300 and 1000, with most estimates at about 500. Most of this bacteria is not harmful to humans at all, but rather assists in maintaining health. These microbes help in the digestion of unutilized  energy substrates.

Human cells heavy hitters- The cells which are most numerous are red blood cells which are around 24.9 trillion. But the cells which contribute most to our mass are muscle cells. Since, women have lesser blood volume, so their bacteria to human cell ratio may be 30 percent higher than that of men.

 Toilet makes you more you- Most of the bacteria live in our colon which is around 39 trillion. Through every bowel movement, you get rid of a few trillion bacteria and the ratio is flipped in favor of human cells. So, if some wise person advises you to be yourself, then you must clarify whether he wants you to go to toilet.

We know now that if you really wanna be you, go to the loo.

References-
https://en.wikipedia.org/wiki/Human_microbiota
http://www.nature.com/news/scientists-bust-myth-that-our-bodies-have-more-bacteria-than-human-cells-1.19136
https://www.sciencenews.org/article/body%E2%80%99s-bacteria-don%E2%80%99t-outnumber-human-cells-so-much-after-all
https://en.wikipedia.org/wiki/Gut_flora

How empty are we? A nerdy challenge.

Anna invited his three friends Raga, Arke and Namo to his home for a party. The party was going on very well and they discussed many issues. Slowly, the discussion heated up and Raga said that he was the most intelligent among those invited. But Arke and Namo also made similar claims. This annoyed Anna and to resolve the issue, Anna gave them a challenge and whosoever won was to be given a dollar each by other two. They sat around a table and Anna started pouring water into a glass and filled it up to the midpoint of its height. Then they had the following conversation-

Anna- On by one, you have to tell me whether this glass is half empty or half full. One who gives the right answer will win. Raga, you tell first.
Raga- Obviously, it is half empty.
Anna- And you Arke?
Arke- No, I think it is half full.
Anna- And what do you think Namo?
Namo- It is neither half empty nor half full. It is half filled with water and half filled with air. So, it is completely filled.
Anna looked at all them with disappointment.
Anna- Unfortunately, you all are wrong. Now stop fighting and enjoy the party.

But, how were they all wrong?  This is because Anna was smart and he knew that everything around us is pretty empty. Even a glass full of water is actually empty. To believe it we need to look things at the atomic level.

Amazing atom- You and all the things around you are made up of atoms. An atom is made up of a nucleus surrounded by a cloud of electrons. Nucleus consists of protons and neutrons. Protons and neutrons are made up of quarks. Electrons orbit around the nucleus at the speed of 2,200 Km/sec. At this speed you can travel around the earth in about 18 seconds. But the fact which Anna used is that an atom is 99.999999999999% empty space. If an atom would have been of the size of a football stadium then the nucleus would have been of the size of a pea at the center of the stadium.

Since, an atom is mostly empty space and everything is made up of atoms, we can say that everything is almost empty. But that empty space is not really empty and consists of quantum fluctuations. So, Anna could have given benefit of doubt to Namo but Anna was not in the mood of letting any of them win. 

Now, whenever we feel sad and have that feeling of emptiness, we know now that we were always like this, quite empty.

Resources-

https://en.wikipedia.org/wiki/Atom

https://www.youtube.com/watch?v=_lNF3_30lUE

Mobile phone radiation and its effects on living beings

Mobile phones have become an integral part of our lives. So much so that, a cellphone can be called as an extended part of our bodies. We start feeling uneasy when separated from our phones. There are more than 4 billion mobile phone users in the world. Mobile phones have made our lives much easier by enabling us to remain connected to the rest of the world. But as with most scientific inventions, there are some side-effects. We are continuously surrounded by radiation from mobile phones and mobile towers. Whether this radiation is harmful to living beings or not is still debatable. There have been many studies carried out on the subject. Before discussing them, we first need to understand what are ionising and non-ionising radiations.

Ionising radiation- If a radiation carries enough energy to knock out electrons from atoms or molecules, then such radiation is an ionising radiation. Gamma rays and X-rays are examples of ionising radiations. This type of radiation is harmful to living beings. Exposure to such radiation can lead to burns, cancers and genetic mutations. So, it is better to stay away from them, unless you want to mutate to get supernatural powers but chances of death after such exposure are much much higher than turning into spiderman.

Non-ionising radiation- If an electromagnetic radiation does not carry enough energy to knock out electrons from atoms or molecules, then such radiation is non-ionising radiation. Sunlight, infrared waves and mobile tower radiation are its examples. They do not produce any lethal effects in living tissues like ionising radiation.

But is exposure to mobile phone radiation completely safe?   In 2011, International Agency for Research on Cancer classified mobile phone radiation as possibly carcinogenic. But WHO added that "to date, no adverse health effects have been established as being caused by mobile phone use". The mobile phone radiation does produce a heating effect and leads to rise in temperature of the surface of the head by a fraction of a degree. But this rise is smaller than the increase in temperature of head under direct sunlight. And to find a link between cancer and mobile phone usage, a Danish group followed 420,000 citizens for 20 years and they showed no increased risk of cancer. But in 2007, a Swedish scientist found that cell phone users had increased risk of tumors and these tumors are more likely to occur on the side of the head that the mobile handset is used. So, we are still not sure whether that next call to your friend is taking you closer to tumor or not. But what about animals? They are also exposed to mobile radiation from towers all the time. Have they been affected in any way?

Effects on other living beings-In 2010, a group of experts in India reviewed 919 studies performed worldwide regarding the effects of cellphone towers on birds, insects, animals, wildlife and humans. Out of the 919 studies, 593 showed that mobile towers radiation had negative impact on animal life. They also held it responsible as a possible cause of decline in population of some species. In another study by Centre for Environment and Vocational Studies, Punjab, 50 eggs of house sparrows were exposed to EMR for 5-10 minutes and all the 50 embryos were found to be damaged. There has been a massive decline in population of house sparrows in most Indian cities in recent years. In 2014, an environmental science experts team attributed this disappearance of house sparrows to mobile radiation. According to them, long term exposure to mobile radiation has damaging effects on the nervous and immune system of small animals. Also, many species use magnetic navigation and mobile radiation can interfere with their sensors and misguide them while navigating and preying.

So, that shiny smart phone in your hands is radiating waves which may or may not be harmful to us but it looks as if they do have a negative impact on our smaller partners on this planet. We know now that our desire of staying connected might be getting fulfilled by the lives of birds and insects. Let's hope that future studies prove this wrong.  

References-
http://timesofindia.indiatimes.com/home/environment/pollution/Mobile-tower-radiation/articleshow/32348258.cms
http://naturalsociety.com/cellphone-tower-emr-damaging-birds-insects-humans/
http://timesofindia.indiatimes.com/city/nagpur/Radiation-from-mobile-towers-affect-birds-MoEF-study/articleshow/10487141.cms
http://www.moef.nic.in/downloads/public-information/final_mobile_towers_report.pdf
https://en.wikipedia.org/wiki/Non-ionizing_radiation
https://en.wikipedia.org/wiki/Ionizing_radiation
https://en.wikipedia.org/wiki/Mobile_phone_radiation_and_health

What color is a mirror?

Mirror, mirror, on the wall, who is the fairest of them all.... That mirror in the story of Snow White was surely magical. But mirrors in real life are also special. Have you ever wondered, what is the color of a mirror? The color of a mirror obviously depends upon its surroundings. The color of an object which you view in the mirror becomes its color. This means that a mirror simply keeps changing its color according to the objects viewed in it. But most other objects normally don't do so. Then what is it that makes mirrors so different? To answer this question, we first need to understand what is a color and what makes things colorful.

What is a color?- Objects by themselves have no color. They simply reflect light falling on them. White light consists of all the colors or wavelengths in the visible spectrum. When a white light falls on an object, it reflects some wavelengths and absorbs the rest. The color corresponding to those reflected wavelengths becomes the color of that object. For example, a red apple is red because it reflects the wavelength corresponding to red color and absorbs most of the rest of the spectrum.

Case of mirror- By above logic, a white object is white as it reflects all the white light or entire visible spectrum falling on it. But then, a mirror also reflects the entire visible spectrum falling on it. Then how is a mirror different from a white object? Why don't we see images in every white object? The answer lies in the type of reflection taking place. There are two types of reflections- diffuse reflection and specular reflection.

Image by GianniG46 - Own work, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=11902338

 Diffuse reflection- In diffuse reflection, the incident ray is reflected in many directions rather than a single direction. It happens because of the multiple reflections taking place beneath the surface of the object. So, when some light finally comes out again from the surface, it can come out in any direction. The light coming to your eyes is a mix of light falling on the object from different directions and you can not see an image in such mixture of rays. This is what happens when you see a white sheet of paper. The light falling on it is reflected back but in different directions and because of this, the image is lost after reflection. In case of red apple, the light corresponding to red color is reflected in many directions and rest of the light is absorbed. So, you see an apple as red in color, without any mirror like images on it. But then how do mirrors work and how are slight images formed on other glossy objects?. This is where specular reflection comes into picture.

Specular reflection- In specular reflection, a ray of light from a single incoming direction is reflected in a single outgoing direction. This is what happens on very smooth surfaces and mirrors. The light rays remain organized,  image remains intact after reflection and this allows images to be seen. For example, if incident rays are parallel then reflected rays are also parallel. To make specular reflection possible, mirrors have a reflecting coating which is usually aluminum or silver.

Mirrors are different from white paper in the way they reflect light. Mirrors show images because of specular reflection while white paper is white because of diffuse reflection. And there are many other objects like glossy white marbles in which the effect of both types of reflections is visible.

If you still want to know the color of mirror, the answer is that it is slightly green. This is because most mirrors reflect green light better than other parts of the spectrum and this gives mirrors a slight greenish tinge.

So, specular reflection makes mirrors possible and diffuse reflection allows us to see most of the things around us. The mirror in your bathroom might not reply to your questions, as in Snow White, but we know now that it does have some magical physics working under the surface.

References-
https://www.rgbworld.com/color.html
https://en.wikipedia.org/wiki/Specular_reflection
https://en.wikipedia.org/wiki/Diffuse_reflection

Antibiotic pollution and super-bugs

You must have heard from your doctor or some other wise person that antibiotics should be taken only when needed and not overused. You must have also heard that if it does become necessary and you are under antibiotic therapy, then you must follow the treatment till the very end. But many of us don't follow this advice. We start feeling good during initial phase of treatment and then we leave taking antibiotics, well before the prescribed course is over.  

Why is it harmful to take antibiotics improperly? The problem is that when you start taking antibiotics, you kill weak disease causing bacteria and also a lot of good bacteria in your body. But if the treatment is incomplete, tough bacteria do not get killed and are able to grow and multiply quickly. Now, this tough bacteria is drug resistant and can spread to other people also.

This can also happen when you take antibiotics in much lower concentration then required to kill bacteria. In this case, bacteria is exposed to antibiotics in amounts which don't kill it but instead offer it a better opportunity to mutate and become resistant.

It is quite unfortunate that people themselves insist on antibiotics. One third of people believe that antibiotics are effective against common cold. It is the most common reason for which antibiotics are prescribed and people also go for self medication, even though antibiotics are useless against viruses. 

Antibiotics use in livestock- In the 20^th century, rising population gave rise to the problem of shortage of meat. In 1950, scientists found that adding antibiotics to animal feed increases growth rate of livestock. Since then, antibiotics are being used in animal farms to increase the growth rates of livestock, poultry, and other farmed animals. Although, proper use of antibiotics in farms prevents a lot of diseases in animals and stops them from spreading to humans but the real problem is overuse of such medicines. Similar to misuse in humans, it gives rise to drug resistant bacteria. When such animals are consumed by humans, these bacteria get an opportunity to spread among human population. 

Are vegetarians safe?- If you are congratulating yourself for being vegetarian, unfortunately, you are also not safe. This is because animal feces are used as manures for crops. And finally, from crops such bacteria can reach your guts.

Antibiotic pollution- About 80% of an antibiotic dose passes straight through the body. So, it is obvious that most of this medicine intake, both by humans as well as animals, ends up in waste water. Most water treatment plants also do not remove them. Waste water from hospitals and antibiotic factories are also a major source of this pollution. According to most researchers, antibiotics usage in world exceeds 250,000 tonnes each year. And this does not take into account release from pharmaceutical plants. Much of these antibiotics find their way into rivers, lakes and other water bodies.These ultimately give rise to the growth of drug resistant bacteria or super-bugs.

So, next time you are having common cold, think twice before popping that pill as it might give you an immediate relief but it might also convert you into a better breeding ground for super-bugs. We know now that improper medication can convert an antibiotic into an anti healthy body.

References-
https://en.wikipedia.org/wiki/Antibiotic_use_in_livestock
http://phys.org/news/2015-03-antibiotic-pollution-waterways-superbugs.html
https://en.wikipedia.org/wiki/Antimicrobial_resistance
http://www.wired.com/2014/12/oneill-rpt-amr/
https://newsinhealth.nih.gov/issue/feb2014/feature1

What are gravitational waves and why are they important?

Finally, the gravitational waves have been detected and with this the last major prediction by Einstein has been confirmed. But what are these gravitational waves and why are they so important? First, you will be disappointed to know that such waves can not be used by you for surfing in space like you can surf on sea waves. But these are still very important as they open up an entire new chapter in the field of physics. Predicted by Albert Einstein on the basis of his theory of general relativity, gravitational waves are ripples caused in the spacetime fabric. Now, if some of you clever people are thinking that why don't we use them for mobile communication to get faster internet just like RF waves, you may be right, but the only problem is that to produce such waves you need a black hole or neutron star in your cellphone. For those who can't arrange a black hole, good news is that your bodies can also produce these waves but such waves are very very tiny to say the least.This is because gravity is a weak force and we need massive bodies to produce any significant gravitational waves. Binary neutron stars in-spiraling, colliding black holes and supernova explosions qualify as valid candidates.

Gravitational waves visualized- When a mass is correctly accelerated through space, these waves travel outward from the source. To visualize it, suppose there is a stretched rubber sheet and you put a billiards ball at the center. Now, the sheet would obviously depress in the middle due to the weight of the ball. If you put a marble anywhere on that sheet, it will roll down towards the ball due to depression in the sheet at center. This is gravity. Now if we put one more billiards ball near the first ball, it will also produce a depression on the sheet. If the balls are close enough, then their depressions will merge slowly and the balls will start moving towards each other. Imagine that they do not move quickly but are rather caught up in a spiral motion on the sheet, like in-spiraling stars. Such motion will produce waves on the rubber sheet and these waves can be called as gravitational waves.

Why we couldn't detect them before? Why it took us a hundred years after Einstein's prediction to detect them directly? This is because gravitational waves produced by distant sources can lengthen or shorten our space only by a factor of 10^-21 or less. This is less than a millionth billionth of the width of a human hair. Such detection can only be done with lasers.This unbelievable task was attempted by LIGO starting in 2002.

LIGO stands for  Laser Interferometer Gravitational-Wave Observatory. It used lasers to measure the changes in distance between ends of  4 km long tunnels. But from 2002 to 2010, it detected nothing. After this it was upgraded into what is known as Advanced LIGO. This was 10 times more sensitive. It started operating in September 2015 and has already achieved success. The gravitational waves detected by LIGO have come from a black hole merger about 1.3 billion light years away from earth.

So, gravitational waves can make you taller and thinner for an instant but such minuscule improvement in your appearance will impress your girl friend only if she uses lasers to measure you. In my opinion, exercise will be a much better option.

This detection has opened up an exciting new field of gravitational wave astronomy. Studying these waves will give us more information about the cosmic events which produce them. And yes, we know now that with this great feat we have found a key in the universe to open a box which is full of mysteries.

References-
http://www.ligo.org/
https://en.wikipedia.org/wiki/Gravitational_wave
https://en.wikipedia.org/wiki/LIGO
https://www.youtube.com/watch?v=gw-i_VKd6Wo
https://openclipart.org/detail/240758/Gravitational-waves-confirmed

What is your speed? -Video

I have converted the post titled "What is your speed?" into a video. Please check it out.

What is your speed?

As you are reading this post, this very moment, you are in motion. You are not only moving but doing so at a very high speed. To observe such movement, you need to look things at cosmic level.The rotation of earth on its axis, revolution of earth around sun and movement of sun in our galaxy, all contribute to this speed.  But we don't notice it because speed is something which is relative. Suppose, you and your friend are sitting in a moving car and you look at a person standing on a footpath. Then you are moving at some speed with respect to that man but you and your friend are stationary with respect to each other. So, to calculate speed, we always need to take some reference as stationary. Let us start looking at various motions that we are part of.

Rotation of earth on its axis- The circumference of earth at equator is around 40,000 kilometers and earth completes one rotation on its axis in around 24 hours. So, speed due to this rotation comes out to be around 500 m/sec. This is 47% more then the speed of sound in air. If you fly at this speed then you will reach Beijing from New Delhi in about 2 hours.

Revolution of earth around sun- Earth covers a distance of around 149.5 million kilometers around the sun in a year. Speed of earth because of this motion comes out to be around 30 km/sec. If you fly at this speed then you will reach Beijing from New Delhi in about 2 minutes.

 Movement of sun in our galaxy- Our sun and other stars in our galaxy are also not stationary. According to estimates, sun's speed is around 200 km/sec as it moves through the milky way. If you fly at this speed then you will reach Beijing from New Delhi in about 19 seconds.

Movement of our galaxy in space- According to estimates, the milky way galaxy is moving at an approximate velocity of  600 km/sec with respect to extra-galactic frames of reference. If you fly at this speed then you will reach Beijing from New Delhi in about 6.3 seconds.

Next time you watch a movie with speedy car chases and actors boasting about their car's high speeds, just remember that it is nothing when compared to the very very high speed at which you are already traveling. We know now that we all are pretty fast and furious.

Links and sources-
https://en.wikipedia.org/wiki/Milky_Way
https://medium.com/starts-with-a-bang/how-fast-are-we-moving-through-space-985bf470378d#.5wv8xef15

The heavy burden of waste

Waste is something which is not useful for us but information about waste management is getting more and more important. Human population always produced waste wherever it thrived but in earlier times the waste produced was small in quantity and mostly biodegradable.With the advent of industrialization, the human population grew rapidly in cities. This rising population combined with various scientific discoveries lead to the rise in waste production. This was obviously pumped by consumerism and lack of farsightedness of governments regarding waste management. Waste processing plants and dumping yards are operating well beyond their capacities. The situation is worse in developing and underdeveloped countries as they lack modern technology for waste treatment. For example, the Ghazipur landfill in East Delhi, spread over 70 acres, already has at least 12 million tonnes of waste. It had a limit of 15 feet of waste which was overshot in 2002 itself. Today it is at least 50 feet tall and still being fed with more waste.

Electrical waste-Around 50 million tonnes of electrical waste is dumped each year. This includes discarded TVs, computers,cellphones,kitchen appliances etc. This is not always waste and can be reused or recycled but only 12.5 % of e-waste is currently recycled. It would have been so nice if we could use that recycle bin icon on our desktops for deleting useless hardware also.

Food wastage- We throw away 7.2 million tonnes of food every year. What is even more shocking is that more than half of that food is edible. According to United Nations, about 21,000 people die every day of hunger or hunger related causes and the main victims are children. This means one person every four seconds is dying of hunger.This is happening when there is plenty of food for everyone in the world.

Supermarkets wastage- Around 20 to 40 percent of fruits and vegetables are rejected by supermarkets before they hit the shelves. The reason being these fruits and vegetables are simply not good looking enough according to their standards. This is because we as buyers also focus a lot on external appearance rather than the actual nutritional value. 

Packaging waste- Be it cardboard boxes, polythene bags, bubble wraps or wrapping papers, all of these simply end up in garbage bins after serving a purpose which can be served by less polluting materials. For example, cloth bags are now slowly replacing polythene bags but the pace of this shift is very slow. At Christmas in UK alone, 83 square kilometers of wrapping paper is used. With the rise of e-commerce also, packaging waste is becoming a huge concern.

 Water wastage- Water is also something which is wasted on a large scale. A single leaking tap can waste as much as 5,000 litres of water in a year and we have many leaking taps. Water is wasted not only through this but also by leaky pipelines. Bad water usage habits of people is also to be blamed and they forget that one in nine people in the world do not even have access to safe and clean drinking water.

 

When you throw waste out of your house, please do not think that your house is clean because this world is your actual house. We have only one earth and we are wasting it. So, next time we throw out those garbage bags, we know now that one day that garbage might throw us out of existence.

Links and Sources-
https://en.wikipedia.org/wiki/History_of_waste_management
http://indianexpress.com/article/india/india-news-india/wastelands-of-india-heres-how-metros-manage-their-trash/
https://www.ovoenergy.com/blog/green/10-shocking-facts-about-waste.html
http://www.poverty.com/

Human brain- nature's marvel

What is it that differentiates humans from other animals? The answer is straightforward, it is our brain. In this post we will present some interesting facts about this marvelous computer created by nature. After reading this post, you will look at that curly organ inside your cranium with more respect. Did I just say look at your brain? I am really not sure whether any living person has literally done so but we will leave that topic right now and focus on wonders of this best supercomputer.

Our brains are much smarter than supercomputers-In the year 2013, Japan's K computer, which is still world's fourth most powerful supercomputer, was used to mimic human brain. But even with its 83,000 processors, it could mimic just one percent of one second's worth of human brain activity and it took 40 minutes to do so. Human brain consists of more than 100 billion neurons and these are connected by well over 100 trillion synapses. A neuron fires around five to fifty times every second. Each neuron is connected to around 40,000 synapses. Obviously, it would take some time before man made supercomputers can even match this natural computing powerhouse. Till then, we need not worry about supercomputers (with brains superior to human brains) replacing our race or enslaving us.

Human brain consumes and generates huge energy- Human brain is only about 2% of body's weight but consumes 20% of oxygen and energy. Such high energy is required for large number of calculations which it carries out. It produces about 12-25 watts of electricity. It would be so convenient if you could charge your mobile phone from your brain's electricity through some neural charger. But this energy sucked from your brain might lead to some part of it going down due to shortage of energy. So, caution is advised.

Ten percent brain usage myth- Some people say that we use only 10% of our brain. This is simply a  myth and has no scientific basis. Brain scans have shown that we use most of our brains most of the time. So, forget about that magic pill which will turn you into a super genius by enabling access to all your brain's potential.

Dehydration affects our brains quickly- This is because 73% of human brain is actually water. So, losing water from your body can also lead to your brain losing memories. But this not a very smart way to get rid of bad memories because dehydration not only effects your memory but also your attention and cognitive skills.

Human brains are now shrinking- We normally think that human race is getting smarter and our brain sizes must be increasing. But this is not true. From early primates to Homo sapiens, the brain has grown. But this increase in brain size stopped with neanderthals. The average brain size has now been shrinking over the past 28,000 years. We are not even getting smarter. Average IQs have been going down 1.6 points per decade. So, it is only our phones which are getting smarter, not us.

Congratulate your brain, it just read few amazing facts about itself. We know now better, how much our grey matter matters. 

Links and sources-
http://bebrainfit.com/human-brain-facts/
http://www.factslides.com/s-Brain
https://en.wikipedia.org/wiki/Evolution_of_the_brain