My Science School

Do the names Sudan, Martha, and George ring a bell? And, what is common to them? Sudan, a male northern white rhinoceros; Martha, a passenger pigeon and George, a Hawaiian tree snail were all the last of their kind (none of them is alive today). Thankfully, the world has been alive to the concerns of extinction for a while now. Which explains concerted conservation efforts globally to ensure we do not forever lose species as an unfair consequence of our own actions. Population decline in several species has been reversed, while some have been stopped from going extinct. But should our focus be only on species teetering on the edge of extinction and whose numbers are plummeting? Come, let's find out.

Nature is limitless. Or, is it? Even as recently as the 19th Century, extinction at sea was deemed impossible. "given the reproductive capacity of marine organisms and the impracticality of overfishing”. Species such as the passenger pigeon, the northern cod (a type of fish), the plains bison, the American chestnut (a deciduous tree), and the eastern white pine were once considered super-abundant, and their decline/disappearance, inconceivable. But the reality in all these cases has been different. And points to the fact that common species face decline and extinction too.

It's wise to remember that several species on the brink of extinction started off as abundant or common. Abundance offers only a "partial buffer” against extinction, and the focus should be on the rate of decline because abundant species "are not immune to decimation”. For instance, a study of North American birds uncovered that “three billion birds on this continent within the past two generations” were lost. The focus on common species is as important as on rare ones because “the shifts in abundance of common species can translate into sizeable shifts in ecosystem functioning".

 Take the case of birds. Given the amount of “insects they eat, the flowers they pollinate and the seeds they disperse”, a sudden and drastic decrease in the population of a common species can spell disaster in an ecosystem. Apart from this, studies show that encounters in the natural world-even a butterfly in a garden- improve the mental health of humans. When common species go, so will our chance of such encounters.

While rare species do require the attention they get,” the extinction of Commonness” should be prevented. And this can be done when we “monitor nature closely, guard against complacency and invest for the long term.”

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Most people think that sand is plentiful, but sand is a non-renewable resource. The demand for it actually exceeds supply and the rate at which we are using it, we will soon be running out of it. Let's find out how sand is formed and about the effects of indiscriminate mining of sand on the environment.

Formation of sand

Sand is a naturally occurring granular material composed of finely divided rock and mineral particles. It is found on beaches and deserts. It is formed by the breaking down or erosion of large boulders by wind or water.

Sand is a very important mineral. It can be used to make concrete which is used in buildings to help support the structures. It is used to make glass, computer chips and to store nuclear waste. It can also be used as a mixer with salt to prevent the formation of ice on roads.

Sand mining

The extraction of sand is called sand mining. Sand can be mined from sand dunes, beaches and even dredged from river and ocean beds.

The main reason sand is extracted is to make concrete, which is in great demand because of the booming construction industry. River sand is considered the best for this purpose. It has jagged edges and is not rounded like desert sand. It also does not contain salt like beach sand. But since there isn't enough sand on river beds, sand found on beaches and creeks is also used after removing the salt.

Harms the environment

Sand plays an important role in protecting the coastal environment. It acts as a buffer against strong tidal waves and storm surges by reducing their impact as they reach the shoreline.

Indiscriminate river bed mining harms the environment. It also leads to the deepening of rivers, change in the course of rivers and soil erosion. The river-plains become more vulnerable to flooding. Riverbed mining also affects groundwater recharge and the foundation of bridges, causing them to collapse.

When sand is taken away, all the life forms and biodiversity it supports also get destroyed. Indiscriminate beach and ocean mining have caused entire beaches and whole islands to disappear.

Where is sand mining rampant?

Illegal sand mining is rampant in developing countries like India and China, where construction is on the rise. Rich countries import sand from poor and developing countries. Singapore, for instance, is expanding its physical borders by importing sand from poorer countries like Cambodia, which, as a result is losing its beaches.

In India, mining licences are issued to contractors. The licences limit the quantities of sand that can be taken and the locations from where it can be mined. Sand mining policies are framed by state governments in India. Unfortunately, these laws are usually not enforced. There is hardly any monitoring either.

Serious crime

Markets for sand in India are dominated by sand mafias, criminal enterprises that mine and sell sand illegally. Although illegal sand mining is a serious environmental crime, there is little awareness about it. As it’s a rural issue, urban people are unaware of it unless they see it happening at a beach where they are holidaying. Also, many don't want to register an official complaint against such illegal activities as it can be dangerous.

The UN took a long time to wake up to this issue’. The first-ever UNEP (United Nations Environment Programme) round-table on sand sustainability took place in October 2018 at Geneva, where I, as a keynote speaker, made a virtual presentation on the issue: A sustainable policy on sand trade should be a part of the political agenda of national governments everywhere.

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In 1918, the United States Navy began using zip fasteners in the clothing and other gear of its men during World War I. By the 1920s, zips could be found in all kinds of clothing, footwear, bags and suitcases. The zip finally arrived on the world scene when fashion designers began using it for haute couture.

The zip was the creation of American inventor Whitcomb Judson. He liked wearing high boots that were all the vogue in 1893, both among men and women. The boots had long shoelaces which took ages to do up. Judson designed a fastener which he called a ‘clasp locker’. It had a slider to link hooks and rings but was clumsy and frequently jammed. The invention was not a success.

It was only 20 years later, in 1913, when Judson employed Swedish engineer Gideon Sundback that the zip took on its present form-two fabric strips with metal or plastic teeth that locked when the zip was pulled closed and unlocked when it was opened.

Judson did not live to see the success of his invention. He died in 1909.

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In 1925, after graduating from high school, Earl S. Tupper set out to make his fortune. A farm boy from New Hampshire, USA, Tupper started a successful business in tree surgery and landscaping. But Tupper Tree Doctors went under during the Great Depression. Tupper found a job in DuPont's plastics division. A year later, he left to form his own plastics company, supplying gas masks to American troops fighting World War II.

After the war, Tupper turned to producing plastic consumer goods. The plastic available then was brittle, smelly and slimy, so he first invented a process to change polyethylene slag, a by-product of petroleum, into a plastic that was not only durable and solid, but clean and clear. However, what made Tupper’s plastic containers revolutionary was an air- and water-tight seal.

By 1946, Tupper was selling a variety of plastic containers in a range of colours, but sales weren't brisk. It was when he adopted the method two local salesmen were using, to sell Tupperware worldwide, that his profits skyrocketed. They introduced the products to housewives at a ‘party’ hosted by one of the women at her home! Tupperware Home Parties became a national, then an international, phenomenon in the 1950s. It enabled Earl Tupper to sell his company for $16 million in 1958.

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Did you know that the same Velcro that allows you to strap on your floaters in an instant, is also used in the Jarvik-7 artificial heart to attach the chambers? NASA astronauts find Velcro indispensable-it holds down objects which would otherwise float away in zero gravity.  

Swiss engineer Georges de Mestral got the idea for Velcro in 1955, when he hike with his dog. When he returned home, he found innumerable burrs stuck to his coat and socks and to the dog's fur. Curious, De Mestral examined a burr under a microscope. He discovered that it had tiny hooks on its surface that caught in the loops of the fabric (and animal fur). De Mestral devised a way of reproducing the hook and loop arrangement in woven nylon. He called it Velcro-from the French velours (velvet) and crochet (hook).

Velcro can be reused hundreds of times, sometimes outlasting the product to which it is attached! It is peelable and has enormous shear strength or resistance to sideways forces. A piece less than 1.2 cm square can support a load of 1 tonne! Today Velcro is used in an infinite number of products, comes in various colours and is made not only from nylon but also from steel and plastic.

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Read on to know how Albert Szent-Gyorgyi found a cure for scurvy, a disease caused by a lack of vitamin C.

In 1928, a Hungarian-born US biochemist, Albert Szent-Gyorgyi, isolated an unknown substance from the adrenal glands of an ox. He named it hexuronic acid.

He soon discovered that hexuronic acid could also be obtained from oranges, lemons and cabbages. One thing common to these three sources was that they were all believed to be rich in vitamin C, a substance no one had been able to isolate till then but which was known to cure scurvy.

It occurred to Szent-Gyorgyi that hexuronic acid and vitamin C might be one and the same thing. He injected hexuronic acid into some guinea pigs that had scurvy, and waited to see what would happen. If hexuronic acid were indeed the same as vitamin C, the guinea pigs would get cured. And that is exactly what happened. The animals recovered from the disease.

He wanted to repeat the experiment but he had run out of hexuronic acid. He had to get some more, but how? It was not easy to come by adrenal glands of oxen, the best source: getting it from lemons and oranges was a laborious process.

He was pondering over the problem at dinnertime when his wife served him freshly ground chilli (paprika) with his food. He had never been fond of paprika but now he looked at it with new interest. He had tested many fruits and vegetables for hexuronic acid, but not paprika. Could it give him the acid he was so desperate to get his hands on?

He took it to his laboratory and tested it for its contents - and it was then that he fell in love with the spice. It was loaded with hexuronic acid!

Within a few weeks, he produced three pounds of pure crystalline hexuronic acid. He fed it to vitamin C deficient guinea pigs and got the same results as earlier the animals recovered from scurvy. There was no difference between hexuronic acid and vitamin C.

 When Szent-Gyorgyi received the Nobel Prize for his work in 1937, ‘Time’ magazine dubbed it the ‘Paprika Prize’.

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Our Earth recently had its brush with a green comet. The last time it visited us was some 50.000 years ago. It is unlikely to return for millions of years. Astronomers and space enthusiasts around the globe looked up to catch a glimpse of this unique visitor.

Christened C/2022 E3 (ZTF), the comet was discovered in March 2022 by astronomers. The comet which had been in the skies for close to a month since mid-January has now travelled outwards, away from Earth and out of our solar system. The comet came from the Oort Cloud.

And if you missed the comet this time, rest assured. There are plenty of comets around which will swing past us and who knows maybe the next one will be bigger and brighter! With so much of discussion around comets, let’s learn more about them.

Comets

The comets are leftovers after the formation of the solar system 4.6 billion years ago. These frozen leftovers are made of dust and ice and orbit the Sun. These ancient objects are often referred to as time capsules as they contain material back from the time the Sun and the planets were formed. They are important as they are believed to hold vital clues regarding the formation of our solar system. They are known for their long tails. The current known number of comets is 3.743

Comets are found to exist in a disk beyond Neptune's orbit called the Kuiper Belt. These are called short period comets. They take less than 200 years to orbit the Sun. Other comets east in the Oort Cloud, the outer edge of the solar system. These are called long-period comets as they take larger periods to orbit the sun.

Halley's comet

Halley is the most famous of the lot. Earlier comets were thought to pass through the solar system only once. In the early 1700s, it was English astronomer Edmond Halley who suggested that the bright comet reported in 1531, 1607 and 1682 was one and the same. That it was a single comet making return trips. He predicted that it would return in 1758. The comet did and it was named in his honour.

Why do comets have a tail?

The most distinctive characteristic of a comet is its tail. When a comet approaches the Sun, the heat evaporates the comet's gases. The dust and gases start moving away from the nucleus of the comet. The Sun's radiation pressure and particles coming from the Sun start pushing the gas and dust stream away from the nucleus into a bright tail that extends to millions of miles.

 In fact, a comet has two tails. While one appears to be white and is made of dust, the other is blush in colour and is comprised of ions and electrically charged gas molecules.

A comet's lifetime

As the comet completes each orbit around the Sun, it loses material from the surface of its nucleus. Its aging starts and it starts dimming in appearance. And over time it loses all the ices in the nucleus and the tail also disappears. The comet changes into a dark rocky mass or fizzles into dust.

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The Indian judicial system has picked up the concept of Public Interest Litigation from American jurisprudence.

You must have often read in the newspapers about people filing Public Interest Litigation (PIL) in the court of law. However, do you know what it is?

PIL

PIL is a legal action filed in a court of law for the enforcement of a public interest. Justice Bhagwati launched the concept of a PIL by relaxing the locus standi (legal capacity to sue or approach courts) rule in 1980. Earlier, only those who were injured by an action could approach the courts.

The Indian judicial system has picked up the concept of public interest litigation from American jurisprudence.

First PIL

The earliest PIL was filed by G. Vasantha Pai several decades ago in the Madras High Court against its sitting Chief Justice S. Ramachandra lyer over his age discrepancy. It was found that the judge had forged his birth date to avoid compulsory retirement at the age of 60.

In the early years, PIL was used to get justice on issues such as rescuing bonded labourers from inhuman work conditions and securing the release of prisoners in Bihar who were kept in jail even after their punishment term was complete

Filing PIL

Any Indian citizen can file a PIL. The issue regarding the PIL is not restricted to any specific list or subject. The only condition that validates a PIL is that the issue being raised should bear significant public interest and not for private gain alone.

The PILS can comprise subjects such as environment, human rights, road safety, exploitation, and atrocities of different kinds.

However, the heavy flow of PILS has led to a greater clogging of the courts that leads to pushing traditional litigation to more delays. Such PILS threaten the entire judicial structure.

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Lithium resources have been discovered for the first time in india's Jammu and Kashmir. What is lithium and why is the discovery significant for the country? Let's find out....

Crucial in rechargeable batteries

 Lithium in its pure form is a soft, silvery white alkali metal which is highly reactive. It is the lightest metal known to us. Not found naturally as a metal, lithium is available in small amounts as a mineral in most rocks. This mineral is crucial in the manufacturing of batteries for electric vehicles, laptops, mobile phones, and other smart devices. Lithium is also used to make aircraft parts as it is light weight. India has so far been relying on imports for the rare mineral. Did you know Bolivia has the largest lithium resources globally?

A major boost

The discovery of the 5.9-million tonnes of "inferred" lithium resources at Salal village in Reasi district by the Geological Survey of India will serve as a major boost to the manufacture of rechargeable batteries for personal devices and electric cars in India and reduce the country's dependence on imports for the mineral. If you wonder what "inferred” lithium resource means, it is a resource for which "quantity, grade and mineral content are estimated only with a low level of confidence". It indicates a preliminary stage of assessment. The mineral blocks are likely to be auctioned after approval from the Central Government.

A game-changer

Of 98 million tonnes of lithium resources found globally. India has over 5% of the resources. According to an official, the project to extract the metal will be a game-changer for the local youths as it will generate ample employment opportunities for them.

With the world keen on transitioning to electric vehicles to reduce carbon emissions, the discovery can help meet India's growing demand for lithium. India wants EVs to make up 30% of new automobiles by the year 2030.

However, environmentalists have a different take on lithium extraction. They say the process of mining lithium is not eco-friendly as it requires a lot of water. Lithium is extracted from hard rocks and underground reservoirs. Besides, lithium extraction releases huge amounts of carbon dioxide into the atmosphere.

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Additive manufacturing, more commonly identified as 3D printing, allows for the fabrication of complex parts from functional or biological materials. As objects are constructed one line or one layer at a time, conventional 3D printing can be a slow process.

Scientists from the Max Planck Institute for Medical Research and the Heidelberg University have demonstrated a new technology to form a 3D object from smaller building blocks in a single step. They utilise the concept of multiple acoustic holograms to generate pressure fields.

Sound exerts force

If you've ever been near a powerful loudspeaker, you would be aware that sound waves exert forces on matter. When high-frequency ultrasound that is inaudible to the human car is used, the wavelengths can be pushed into the microscopic realm. This would allow researchers to manipulate building blocks that are incredibly small, including biological cells.

This research group had previously shown how to form ultrasound using acoustic holograms, which are 30 printed plates made to encode a specific sound field. The scientists had devised a fabrication concept to use these sound fields to assemble materials in 2D patterns.

Holds promise

For this research, the team expanded the concept further by capturing particles and cells freely floating in water and assembling them into 3D shapes. Additionally, the new method works with materials such as glass, hydrogel beads, and biological cells.

Ultrasound affords the advantage that it is gentle for using biological cells and that it can travel deep into tissue. Hence, it can be used to remotely manipulate cells without harm. Scientists believe that their technology of creating 3D objects with sounds holds promise as it can provide a platform for the formation of tissues and cell cultures.

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On March 5, 1590, Danish astronomer Tycho Brahe observed a comet. This was one of the many observations made by Brahe, known for his comprehensive astronomical observations.

The invention of the telescope allowed astronomy to peer further and further still improving technology and better equipment implies that our modem telescopes allow us to see way beyond what our predecessors imagined possible. And yet, there was a time when there were no telescopes when astronomical observations were still being done.

Danish astronomer Tycho Brahe is best known for measuring and fixing the positions of astronomical bodies and developing astronomical instruments. While his observations paved the way for future discoveries, the fact that these were the most accurate measurements from a time when the telescope had yet not been invented makes it all the more special.

Born in Denmark in 1546, Brahe’s parents were part of the nobility. Abducted at a very early age by his wealthy uncle, Brahe was raised by him and attended universities in Copenhagen and Leipzig

Drawn to astronomy

While his family wanted him to be a lawyer and he even studied the subjects, Brahe chose to pursue astronomy eventually. The total eclipse of the sun on August 21, 1560, and the conjunction of Jupiter and Saturn in August 1563- Brahe's first recorded observation -were natural events that pushed Brahe to devote his lifetime to astronomy.

In 1566, Brahe fought Manderup Parsberg, his third cousin and a fellow student, in a duel over who was the better mathematician. While Parsberg and Brahe went on to become good friends after this, Brahe lost a large chunk of his nose during the duel and had to wear a prosthetic nose to mask the disfigurement for the rest of his life. While this nose was long believed to be made of silver, the exhumation of his body in 2010 revealed that it was made of brass.

Brahe observed a supernova in the constellation of Cassiopeia in 1572 and the new star remained visible for nearly a year-and-a-half. He observed a comet late in 1577 and meticulously followed it till it remained visible in January 1578

Against prevailing theory

 While prevailing theory dictated that disturbances in the atmosphere was the reason behind these. Brahe’s measurements showed differently. Brahe was able to show that the supernova never changed with regard to the surrounding stars. And based on his measurements of the comet, he was able to determine that it was at least six times farther away than the moon

These observations elevated Brake to a new level and he acquired an international reputation. His fame earned him a more comfortable life and the backing of the rulers as King Frederick II of Denmark offered him exclusive usage of his own island of Hven and financial support to carry out astronomical observations.

Brahe built a huge observatory on the island and diligently tracked the heavenly bodies, maintaining impeccable notes of the observations. During his time at Hven, Brake observed at number of comets. The one he observed on March 5, 1590 when he was employed in observing Venus was one of the last he tracked down while at the island.

Combined model

Even though Brahe's work laid bare the flaws of the system that was then used, he failed to embrace Polish polymath Nicolaus Copernicus's proposed model of the universe with the Sun at its centre. Brahe, instead, offered a combined model with the moon, and the sun going around the Earth, even as the five other known planets orbited the sun

Brahe's influence waned following the death of Frederick in 1588 and most of his income stopped under Frederick’s son Christian IV. He left Hven in 1597 and after short stays in a couple of places, settled in Prague in 1599 and stayed there until h death in 1601.

It was in Prague that German astronomer Johannes Kepler started working as Brakes assistant. Kepler. ironically. would go on to use Brahe's detailed observations to arrive at his planetary laws of motion and show that planets moved around the sun in elliptical orbits.

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(Pronounced tree-kuhl-ee)

Meaning: This adjective means dark and sticky, like treacle - a thick sweet syrup. Also, too pleasant or kind, or expressing feelings of love in a false way.

Origin: The word comes from treacle - a British term for molasses-originally "an antidote to poison", from the Greek root theriake, "antidote for poisonous wild animals". The sense of "molasses" is recorded from 1690s (the connection may be from the use of molasses as a laxative, or its use to disguise the bad taste of medicine). The use as "anything too sweet or sentimental" is from 1771.

Usage: The film is marked by a treacly sentiment.

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(Pronounced uhn.soo.see.uhns)

Meaning: A noun, insouciance refers to a feeling of careless indifference. It is a lack of concern shown by someone towards something they might be expected to take seriously

Origin: Originating from the French insouciant in the late 18th Century, the word is a combination of the negative prefix in- and soucier, meaning "to worry or disturb." Soucier in turn came from the Latin sollicitus meaning "anxious". The word "insouciance" has been part of the English language since the 1800s.

Usage: She entered the meeting hall with complete insouciance to the fact that she was late.

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(Pronounced vi-cin-i-ty)

Meaning: This word is often used as a synonym of neighbourhood meaning the area around or near a particular place. It can also mean the quality or state of being near or an approximate amount, extent, or degree.

Origin: Vicinity first appeared in English in the 16th Century. It comes from Latin vicus, meaning "row of houses" or “village,” by way of Latin vicinus, meaning neighbouring.

Usage: She lives in Los Angeles, or somewhere in that vicinity.

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(Pronounced as: o-ra-kyoo-ler)

Meaning: An adjective, "oracular” means resembling an oracle or of, relating to, or being an oracle.

Origin: The word is borrowed from the Latin word "oraculum" meaning a divine announcement or a prophetic declaration. Its first known use was in 1631.

Usage: The return of the gypsy to the king's court brought much cheer because if anything could save the king and the kingdom then it was the oracular pronouncements the gypsy would make.

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