Daily Quiz: UPSC Prelims Marathon (Science & Technology ) – August 20, 2020

Benzoic acid is an organic compound which is described by the chemical formula C6H5COOH.

• It consists of a carboxyl group attached to a benzene ring. Therefore, benzoic acid is said to be an aromatic carboxylic acid.
• This compound exists as a crystalline, colorless solid under normal conditions.
• It is white and belongs to the family of carboxylic acid.
• The term ‘benzoate’ refers to the esters and salts of C6H5COOH.
• The commercial production of benzoic acid is done via the partial oxidation of toluene with oxygen, catalyzed by manganese or cobalt naphthenates.

Some important uses of C6H5COOH are listed below.

• The production of phenol involves the use of benzoic acid.
• This compound is used in ointments that prevent or treat fungal skin diseases.
• C6H5COOH is used as a preservative in the food industry.
• Benzoic acid is an ingredient in many cosmetic products, such as lipsticks.
• It is also a precursor to benzoyl chloride.
• One of the components of toothpaste, mouthwash, and face-wash creams is C6H5
• This compound is also used in the manufacture of dyes and in insect repellants.

Keratinocytes are the primary type of cell found in the epidermis, the outermost layer of the skin.

• In humans they constitute 90% of epidermal skin cells.
• Basal cells in the basal layer (stratum basale) of the skin are sometimes referred to as basal keratinocytes.
• By using an indigenously developed hydrogel made of a polymer (polyacrylamide) in lieu of the conventional plastic tissue culture plates, researchers at the Indian Institute of Technology (IIT) Bombay have been able to achieve many-fold increase in the number of skin cells (keratinocytes) cultured in the lab.
• Unlike traditional methods, no feeder layer or drug is needed when cells are grown on the hydrogel substrate.

The center of our Milky Way Galaxy is anchored by a black hole that is nearly 5 million times the mass of our Sun.

• Surrounding it is a chaotic city of stars, gas, and dust that we call Sagittarius A.
• We stacked false-color X-ray, infrared, and radio images into this single picture to show you the different structures hidden inside the core of our Galaxy.
• X-rays (purple) radiate from the super-hot gas trapped in the black hole’s grasp.
• The surrounding dust is heated by friction as it chaotically orbits around the black hole and then glows in infrared light (gold).
• And the enormous pools and three-armed rivers of gas shine in radio light (oranges and reds) to trace the complexity of magnetic fields in this violent neighborhood.

NOTE: A language professor has given a Hawaiian name — Powehi — to the black hole depicted in an image produced in a landmark experiment.

Though the Event Horizon Telescope set out to image both M87 and Sagittarius A* the black hole at the centre of the Milky way, they have succeeded only in imaging the former, despite its being much further away.

Titan and Earth are the solar system’s two places with standing bodies of liquid on the surface. Titan boasts lakes, rivers and seas of hydrocarbons: compounds of hydrogen and carbon like those that are the main components of petroleum and natural gas.

“Titan is the most Earth-like body in the solar system. It has lakes, canyons, rivers, dune fields of organic sand particles about the same size as silica sand grains on Earth”.

Scientists have detected the most ancient type of molecule in our universe in space for the first time ever.

• Helium hydride ion (HeH+) was the first molecule that formed when, almost 14 billion years ago, falling temperatures in the young universe allowed recombination of the light elements produced in the Big Bang.
• At that time, ionised hydrogen and neutral helium atoms reacted to form HeH+, said researchers from The Max Planck Institute for Radio Astronomy (MPIfR) in Germany.
• Despite its importance in the history of the early Universe, HeH+ has so far escaped detection in astrophysical nebulae — cloud of gas and dust in outer space.
• Operating the GREAT far-infrared spectrometer onboard the flying observatory SOFIA, an international team reported unambiguous detection of the molecule towards the planetary nebula NGC 7027.

The Indian bullfrog Hoplobatrachus tigerinus (native to the Indian subcontinent) has rapidly invaded the Andaman Islands after it was introduced there in the early 2000s.

• In human-dominated areas, it now shares space with other native (and often endemic) frog species.
• The bullfrogs are prolific breeders: they have short breeding seasons, and each egg clutch can contain up to 5,750 eggs.
• Its tadpoles are carnivorous and eat other tadpoles (including their own species).
• It is native to the Indian subcontinent (Afghanistan, Bangladesh, India, Myanmar, Nepal and Pakistan) and is the largest frog in India.

Taking a cue from European languages, several of which have the same (Roman letter–based) script, Srinivasa Chakravathy’s team at IIT Madras has, over the last decade, developed a unified script for nine Indian languages, named the Bharati script.

• The team has now gone a step further since developing the script: it has developed a method for reading documents in Bharati script using a multi-lingual optical character recognition (OCR) scheme.
• The team has also created a finger-spelling method that can be used to generate a sign language for hearing-impaired persons.
• In collaboration with TCS Mumbai, the researchers have found a way for persons with hearing disability to generate signatures using this finger-spelling technique.
• The scripts that have been integrated include Devnagari, Bengali, Gurmukhi, Gujarati, Oriya, Telugu, Kannada, Malayalam and Tamil. English and Urdu have not been integrated so far.
• In general, optical character recognition schemes involve first separating (or segmenting) the document into text and non-text.
• The text is then segmented into paragraphs, sentences words and letters.
• Each letter has to be recognised as a character in some recognisable format such as ASCII or Unicode.
• The letter has various components such as the basic consonant, consonant modifiers, vowels etc

It is encouraging that India was reported to be the fourth largest funder of research and development (R&D) in neglected diseases as per the G Finder Survey which tracks global investments in R&D for the neglected diseases.

• This reflects the government’s commitment towards addressing the innovation problem in neglected diseases.
• Neglected diseases are mostly tropical infectious diseases, and the market size for drugs for such diseases is small due to their limited geographical incidence.
• To highlight the common problem of lack of innovation for drugs, diagnostics and vaccines for this basket of diseases, WHO started addressing these as neglected diseases from late 1980s.
• Some examples of neglected diseases are malaria, tuberculosis, leishmaniasis (kala azar), dengue, leprosy, lymphatic filariasis and diarrhoeal diseases.

NOTE: These diseases face an innovation deficit as they are neglected in R&D efforts of the pharmaceutical industry.

• However, it is not just the neglected diseases in the developing world that face this innovation deficit.
• Several rare diseases that affect the developed markets are called “orphan diseases.”
• These are called orphans because the pharmaceutical industry does not find it profitable to develop and market products intended for only a small number of patients suffering from rare diseases.

The discovery of Homo luzonensis, a small-bodied hominin on April 2019, from the island of Luzon in the Philippines was based on studies carried out on seven teeth and six small bones that were recovered.

• The hominin lived at least 50,000-67,000 years ago in the island.
• The discovery of Denisovans, an extinct species of human, in 2008 was based on fragmentary remains.
• Genetic studies carried on a small finger sample suggested that they survived for thousands of years and died out just 40,000 years ago.
• Similarly, in the case of ‘hobbits’ (Homo floresiensis), which was discovered in 2004 in Flores, Indonesia and found to have survived till as recently as 12,000 years ago, the confirmation of its hominin nature came from studying a variety of bones.
• Fairly complete cranium and mandible, right leg, less complete bones of the left leg, hands and feet, and fragments of vertebral column, ribs, sacrum (triangular bone at the base of the spine) among others were recovered and studied.

In 1951, a British explorer named Eric Shipton looking for an alternative route up Mt. Everest found a footprint that appeared to be hominoid.

• He took a picture, and the mystery of the Yeti—a Sherpa word for “wild man”—cast a spell over the world.
• Daniel Taylor, author of Yeti: The Ecology of a Mystery has been searching for signs of this “Abominable Snowman” in the high Himalayas since he was a child.

While there are only claims of sightings of Yeti and giant footprints on snow, results from two studies based on samples collected from the Himalayas do not provide any evidence in support of Yeti. Both studies have indicated that samples belonged to bears.

• An August 2014 paper in the journal Proceedings of the Royal Society B studied two hair samples — one from Ladakh and the other from Bhutan. These had close genetic affinity to polar bears or a previously unrecognised bear species.
• A November 2017 study published in the Proceedings of the Royal Society B analysed 24 mitochondrial DNA samples of hair, tissue, bone, and faeces of Himalayan brown bears and purported Yeti collected from the Tibetan Plateau-Himalaya region.
• Eight of the nine purported Yeti samples matched regional bear populations, including the Himalayan brown bear (Ursus arctos isabellinus).

The results “strongly suggest that the biological basis of the Yeti legend is local brown and black bears”, the researchers concluded.