1.Clues from meteorite to Earth’s mantle

The meteorite originated in the asteroid belt, was sucked in by Earth’s gravity

On November 13, 2015, a meteorite fell near the town of Kamargaon in Assam, India. It weighed a little over 12 kg and scientists decoded its mineral composition and classified it as a chondrite, a variety of stony meteorite. A new study has now shown that by studying this meteorite and its minerals we may find new clues about the Earth’s lower mantle.

Layers of the Earth

“We are always interested in knowing how this planet of ours was formed. The Earth has different layers – the upper, very thin crust, followed by the intermediate silicate mantle which starts from 30 km to 2,900 km depth, and then the centre iron-nickel alloy core. The mantle faces high temperature and pressure. So by studying these meteorites which may have experienced similar high pressure and temperature conditions, we can understand the inaccessible mantle layer in detail,” explains Sujoy Ghosh from the Department of Geology and Geophysics at the Indian Institute of Technology, Kharagpur. He is one of the authors of the paper recently published in Geophysical Research Letters.

Previous studies had noted that the Kamargaon meteorite contains minerals such as olivine, pyroxene, plagioclase and chromite. Olivine is also found in Earth’s upper mantle. It breaks down into bridgmanite and magnesiowustite in Earth’s lower mantle conditions. This breaking down is an important reaction that controls the physical and chemical properties of the Earth’s interior.

Olivine dissociation

Using new high-resolution electron microscopy and spectroscopy, researchers studied this dissociation reaction of olivine in the Kamargaon meteorite. They noted an alternative mechanism and reactions that may be driving the transformation of olivine. “It is possible that when materials are transported to the lower mantle by convection or subduction, there would be high-temperature conditions in the lower mantle that would cause this dissociated reaction,” adds Dr. Ghosh. The results suggest what processes and reactions may be involved in the formation of Earth’s lower mantle.

Sucked by gravity

“This meteorite originated from the asteroid belt, between Mars and Jupiter, and was somehow sucked by Earth’s gravity. By studying different meteorites, we can understand in detail about their parent body and in the process understand our own planet and its formation,” adds first author Kishan Tiwari, research scholar, IIT Kharagpur. “The question remained, however, if this process we identified could actually occur in nature. The mechanism needs to be verified in natural terrestrial samples in future studies.”

Sources of Information about the interior of the earth
Direct Sources:
Rocks from mining area
Volcanic eruptions
Indirect Sources
By analyzing the rate of change of temperature and pressure from the surface towards the interior.
Meteors, as they belong to the same type of materials earth is made of.
Gravitation, which is greater near poles and less at the equator.
Gravity anomaly, which is the change in gravity value according to the mass of material, gives us information about the materials in the earth’s interior.
Magnetic sources.
Seismic Waves: the shadow zones of body waves (Primary and secondary waves) give us information about the state of materials in the interior.
Structure of the earth’s interior
Structure of earth’s interior is fundamentally divided into three layers – crust, mantle and core.

structure of the interior of the earth

Crust
It is the outermost solid part of the earth, normally about 8-40 kms thick.
It is brittle in nature.
Nearly 1% of the earth’s volume and 0.5% of earth’s mass are made of the crust.
The thickness of the crust under the oceanic and continental areas are different. Oceanic crust is thinner (about 5kms) as compared to the continental crust (about 30kms).
Major constituent elements of crust are Silica (Si) and Aluminium (Al) and thus, it is often termed as SIAL (Sometimes SIAL is used to refer Lithosphere, which is the region comprising the crust and uppermost solid mantle, also).
The mean density of the materials in the crust is 3g/cm3.
The discontinuity between the hydrosphere and crust is termed as the Conrad Discontinuity.
CONRAD and MOHO discontinuities

Mantle
The portion of the interior beyond the crust is called as the mantle.
The discontinuity between the crust and mantle is called as the Mohorovich Discontinuity or Moho discontinuity.
The mantle is about 2900kms in thickness.
Nearly 84% of the earth’s volume and 67% of the earth’s mass is occupied by the mantle.
The major constituent elements of the mantle are Silicon and Magnesium and hence it is also termed as SIMA.
The density of the layer is higher than the crust and varies from 3.3 – 5.4g/cm3.
The uppermost solid part of the mantle and the entire crust constitute the Lithosphere.
The asthenosphere (in between 80-200km) is a highly viscous, mechanically weak and ductile, deforming region of the upper mantle which lies just below the lithosphere.
The asthenosphere is the main source of magma and it is the layer over which the lithospheric plates/ continental plates move (plate tectonics).
The discontinuity between the upper mantle and the lower mantle is known as Repetti Discontinuity.
The portion of the mantle which is just below the lithosphere and asthenosphere, but above the core is called as Mesosphere.
Core
It is the innermost layer surrounding the earth’s centre.
The core is separated from the mantle by Guttenberg’s Discontinuity.
It is composed mainly of iron (Fe) and nickel (Ni) and hence it is also called as NIFE.
The core constitutes nearly 15% of earth’s volume and 32.5% of earth’s mass.
The core is the densest layer of the earth with its density ranges between 9.5-14.5g/cm3.
The Core consists of two sub-layers: the inner core and the outer core.
The inner core is in solid state and the outer core is in the liquid state (or semi-liquid).
The discontinuity between the upper core and the lower core is called as Lehmann Discontinuity.
Barysphere is sometimes used to refer the core of the earth or sometimes the whole interior.
Temperature, Pressure and Density of the Earth’s Interior
Temperature
A rise in temperature with increase in depth is observed in mines and deep wells.
These evidence along with molten lava erupted from the earth’s interior supports that the temperature increases towards the centre of the earth.
The different observations show that the rate of increase of temperature is not uniform from the surface towards the earth’s centre. It is faster at some places and slower at other places.
In the beginning, this rate of increase of temperature is at an average rate of 10C for every 32m increase in depth.
While in the upper 100kms, the increase in temperature is at the rate of 120C per km and in the next 300kms, it is 200C per km. But going further deep, this rate reduces to mere 100C per km.
Thus, it is assumed that the rate of increase of temperature beneath the surface is decreasing towards the centre (do not confuse rate of increase of temperature with increase of temperature. Temperature is always increasing from the earth’s surface towards the centre).
The temperature at the centre is estimated to lie somewhere between 30000C and 50000C, may be that much higher due to the chemical reactions under high-pressure conditions.
Even in such a high temperature also, the materials at the centre of the earth are in solid state because of the heavy pressure of the overlying materials.
Pressure
Just like the temperature, the pressure is also increasing from the surface towards the centre of the earth.
It is due to the huge weight of the overlying materials like rocks.
It is estimated that in the deeper portions, the pressure is tremendously high which will be nearly 3 to 4 million times more than the pressure of the atmosphere at sea level.
At high temperature, the materials beneath will melt towards the centre part of the earth but due to heavy pressure, these molten materials acquire the properties of a solid and are probably in a plastic state.
Density
Due to increase in pressure and presence of heavier materials like Nickel and Iron towards the centre, the density of earth’s layers also gets on increasing towards the centre.
The average density of the layers gets on increasing from crust to core and it is nearly 14.5g/cm3 at the very centre.

2.Why bacteria develop multi-drug resistance

E. coli were evolved in fluctuating and steady environments and observed

During evolution, the fitness costs experienced by bacteria under constant and fluctuating environments pose an unsolved problem. One way of seeing this is through the example of multi-drug resistance. It is not clear why some bacteria evolve multi-drug resistance while others do not. New research from the Population Biology Lab at IISER Pune could hold a key to this and a similar class of puzzles.

Public health menace

Multi-drug resistance is a menace in public health, however it is a fascinating problem to an evolutionary biologist who sees it from this angle: possessing multi-drug resistance implies that the bacteria is adept at handling multiple antibiotics simultaneously. This would increase its fitness appreciably. Given that antibiotics exert a very strong selection pressure, it would appear that every bacteria in nature can become multi-drug resistant, which is not the case. “One of the reason given for why that does not happen is fitness cost,” says Sutirth Dey, in whose lab the study was carried out.

When bacteria become fit in one environment, they either lose fitness or fail to increase fitness in other environments. “Our study is showing that when the environment is fluctuating, large (but not small) populations can by-pass this effect,” he adds.

Yashraj Chavhan, Sarthak Malusare, and Sutirth Dey studied populations of small and large sizes across different constant and fluctuating environments and then subjected the evolved populations to whole-genome, whole-population sequencing analysis. They found that small populations acquire a certain set of mutations which allow them to survive in one environment while paying a cost in others. Large populations also develop these mutations but, in addition, have certain compensatory mutations that together give them fitness to survive in different environments. Thus, population size determines the kind of mutations available to the bacteria, which in turn, leads to the type of fitness costs they evolve.

Population size matters

In the paper, published in Ecology Letters, the group studied approximately 480 generations of E. coli in four types of steady environments consisting of different carbon sources: galactose, thymidine, maltose and sorbitol; also in one fluctuating environment in which the carbon source changed unpredictably between these four. Bacteria cannot use all carbon sources similarly. “Which carbon source is available impacts the bacterium’s ability to survive and grow. Since this is a very basic requirement for survival and growth, we decided to study what the availability of different kinds of carbon sources does to their evolution,” says Prof Dey.

The study showed that, all else being equal, whether the bacteria pay fitness costs or not will depend on the population size they evolve in. Further, on doing whole-genome, whole population sequencing, the researchers found that the larger populations contained greater number of mutations. The smaller populations only had mutations related to metabolism of one kind of carbon source whereas the larger populations had known mutations for metabolism of multiple types of carbon sources. “We believe that this is the reason that the larger populations were able to bypass the costs,” he clarifies.

3.ED transfer of defaulters’ assets to PSBs

Will handing over the properties of Mallya, Modi and Choksi to banks help tide over the bad loans crisis?

The story so far: The Enforcement Directorate (ED) on Wednesday came out with a statement saying that it had seized assets worth ₹18,170.02 crore belonging to three fugitive businessmen. The seized assets belong to liquor baron Vijay Mallya and diamond traders Nirav Modi and Mehul Choksi — all three left India before law enforcement agencies could nab them for fraud. The ED estimated that the seized assets would help public sector banks recuperate about 80% of their losses from the loans given to companies connected to these three individuals. It also noted that assets worth 40% of the total loss amount had already been handed over to the banks concerned. This included cash worth approximately ₹6,600 crore obtained through the sale of shares. Finance Minister Nirmala Sitharaman later said that fugitive and economic offenders would be actively pursued by the government and that their properties would be attached for the dues to be recovered.

Why did the ED seize and sell the assets of the businessmen?

The three fugitive businessmen have been outside India for a few years now after allegedly cheating banks. The ED stated that these businessmen caused a total loss of ₹22,585.83 crore to banks by “siphoning off the funds through their companies”. Mr. Modi and Mr. Choksi have been pursued for committing fraud using unauthorised letters of undertaking (LoUs) that caused a loss of about ₹11,500 crore to the Punjab National Bank. It has been alleged that Mr. Modi colluded with Punjab National Bank employees in Mumbai to create unauthorised LoUs in his favour. On the other hand, Mr. Mallya has been accused of cheating banks of ₹9,000 crore by siphoning business loans towards other purposes. Banks also alleged that Mr. Mallya had offered personal guarantees for the loans taken by his business.

Indian authorities have been trying to extradite these businessmen to India to prosecute them under the Prevention of Money Laundering Act (PMLA) and other laws. In 2019, the ED managed to convince courts to declare Mr. Mallya and Mr. Modi fugitive economic offenders under the Fugitive Economic Offenders Act, 2018, allowing it to seize assets owned by them. Of the ₹18,170.02 crore seized by the ED under the PMLA, assets worth ₹9,041.5 crore have already been handed over to banks, according to the agency.

Will the recovered money help banks?

The actual cash worth ₹6,600 crore transferred by the ED will obviously help public sector banks, which have been troubled by bad loans, to recoup some of their losses. However, the recovered amount is unlikely to have any major impact on the overall health of banks. This is simply because bank losses attributed to these fugitives are tiny compared to the overall amount of bad loans in the books of banks. It is estimated that the total bad loans of Indian banks stood at more than ₹8 lakh crore at the end of September 2020. Some believe it could easily cross ₹10 lakh crore by the end of the financial year 2022 due to the impact of the two waves of the COVID-19 pandemic on repayments.

Further, doubts remain over the actual value of the remaining assets that have been seized by the ED. The money that has been transferred to banks came from the sale of Mr. Mallya’s shares in United Breweries Holding Limited (UBHL). Other assets seized by the ED belonging to these fugitives may not be as liquid as the UBHL shares. For example, when banks tried several times in the past to sell assets, such as various properties, owned by Mr. Mallya, the sales did not attract significant buyer interest. So, it is likely that banks may face hurdles trying to sell illiquid assets owned by the trio and may not actually be able to recover the amounts cited by the ED in its statement on Wednesday.

Why is the recovery process long?

It is also worth noting the delays that have plagued the entire recovery process and the costs associated with such delays. Banks were unable to sell the UBHL shares belonging to Mr. Mallya as the sale was contested in courts by various parties. In fact, it was only after a PMLA court order last month restored the UBHL shares from the control of the ED to the banks that the current sale has transpired. The ED had earlier moved the PMLA court after the Debt Recovery Tribunal, Bengaluru, also ruled in favour of transferring the shares to the banks.

The true scale of the losses to banks may also be higher when the cost of interest foregone by banks since the defaults is taken into consideration. Even when a borrower defaults, banks need to continue paying interest to lenders. There is also the opportunity cost of the interest that the banks could have earned if they had lent the money to a more eligible borrower.

What are some systemic issues?

The seizure and the liquidation of assets may help in paying back a significant share of the liabilities that these fugitives owe to banks. However, efforts to extradite them are likely to continue as they are accused by banks of not just default but also various other frauds, including siphoning off loans that were sanctioned for business purposes. It is unclear when the trio will actually reach India, given the legal procedures involved in their extradition process.

More importantly, many still believe that these asset seizures do not go far enough to address the root problem of banking scams in India, which is systemic. For one, loans given by public sector banks to powerful industrialists were often influenced by crony, non-business considerations. When the Indian economy was booming, most of the loans that were disbursed by public sector banks were concentrated towards a small group of industrialists. There was also very little oversight of the purposes for which these loans were put to use. At one point, these loans to corporates constituted almost three-fourths of the total bad loans in the banking system. This issue was brought to light by former Governor of the Reserve Bank of India, Raghuram Rajan, during his tenure.

Addressing the problem of crony lending will require deep structural changes in the banking sector. Currently, India’s banking industry is dominated by public sector banks, which are heavily prone to political influence of various kinds, according to experts. This affects the health of banks, which are forced to lend as per special interests while ignoring any business sense. Structural reforms against this, however, are hard to come by, given that they will upset special interest groups.

Is the new debt resolution regime robust?

Despite laws such as the Insolvency and Bankruptcy Code (IBC), 2016, recovery of dues from defaulters remains a prolonged process for banks as courts are burdened with cases.

Under the new regime, the amount lenders have managed to recover from defaulters has improved significantly when compared to the pre-IBC regime. This is true even as a few large corporate resolutions may have skewed the numbers in favour of the IBC regime. The time taken for recoveries from corporate defaulters has also improved from about four years to about 400 days. However, cases have been piling up and the existing Benches of the National Company Law Tribunal have been unable to dispose of cases within deadlines. This may extend the resolution process of troubled companies into several years, which was the case before the IBC regime. Further, when the resolution of a company is deemed infeasible and the company is liquidated, the recovery made by lenders is abysmal due to the absence of a robust market for the sale of stressed assets.

Prevention of Money Laundering Act, 2002 is an Act of the Parliament of India enacted by the NDA government to prevent money-laundering and to provide for confiscation of property derived from money-laundering. PMLA and the Rules notified there under came into force with effect from July 1, 2005. The Act and Rules notified there under impose obligation on banking companies, financial institutions and intermediaries to verify identity of clients, maintain records and furnish information in prescribed form to Financial Intelligence Unit – India (FIU-IND).

The act was amended in the year 2005, 2009 and 2012.

On 24 Nov 2017, In a ruling in favour of citizens’ liberty, the Supreme Court has set aside a clause in the Prevention of Money Laundering Act, which made it virtually impossible for a person convicted to more than three years in jail to get bail if the public prosecutor opposed it. (Section 45 of the PMLA Act, 2002, provides that no person can be granted bail for any offence under the Act unless the public prosecutor, appointed by the government, gets a chance to oppose his bail. And should the public prosecutor choose to oppose bail, the court has to be convinced that the accused was not guilty of the crime and additionally that he/she was not likely to commit any offence while out on bail- a tall order by any count.) (It observed that the provision violates Articles 14 and 21 of the Indian Constitution)

Punishment for money-laundering

The Act prescribes that any person found guilty of money-laundering shall be punishable with rigorous imprisonment from three years to seven years and where the proceeds of crime involved relate to any offence under paragraph 2 of Part A of the Schedule (Offences under the Narcotic Drugs and Psychotropic Substance Act, 1985), the maximum punishment may extend to 10 years instead of 7 years.

Powers of attachment of tainted property

The Director or officer above the rank of Deputy Director with the authority of the Director, can provisionally attach property believed to be “proceeds of crime” for 180 days. Such an order is required to be confirmed by an independent Adjudicating Authority.

Adjudicating Authority

The Adjudicating Authority is the authority appointed by the central government through notification to exercise jurisdiction, powers and authority conferred under PMLA. It decides whether any of the property attached or seized is involved in money laundering.

The Adjudicating Authority shall not be bound by the procedure laid down by the Code of Civil Procedure,1908, but shall be guided by the principles of natural justice and subject to the other provisions of PMLA. The Adjudicating Authority shall have powers to regulate its own procedure.

Presumption in inter-connected transactions

Where money laundering involves two or more inter-connected transactions and one or more such transactions is or are proved to be involved in money laundering, then for the purposes of adjudication or confiscation, it shall presumed that the remaining transactions form part of such inter-connected transactions.

Burden of proof

A person, who is accused of having committed the offence of money laundering, has to prove that alleged proceeds of crime are in fact lawful property.

Appellate Tribunal

An Appellate Tribunal is the body appointed by Govt of India. It is given the power to hear appeals against the orders of the Adjudicating Authority and any other authority under the Act. Orders of the tribunal can be appealed in appropriate High Court (for that jurisdiction) and finally to the Supreme Court

Special Court

Section 43 of Prevention of Money Laundering Act, 2002 (PMLA) says that the Central Government, in consultation with the Chief Justice of the High Court, shall, for trial of offence punishable under Section 4, by notification, designate one or more Courts of Session as Special Court or Special Courts for such area or areas or for such case or class or group of cases as may be specified in the notification.

FIU-IND

Financial Intelligence Unit – India (FIU-IND) was set by the Government of India on 18 November 2004 as the central national agency responsible for receiving, processing, analyzing and disseminating information relating to suspect financial transactions. FIU-IND is also responsible for coordinating and strengthening efforts of national and international intelligence, investigation and enforcement agencies in pursuing the global efforts against money laundering and related crimes. FIU-IND is an independent body reporting directly to the Economic Intelligence Council (EIC) headed by the Finance Minister.

4.Great Barrier Reef

A fabled wonder in danger

Climate change has led to 3 events of coral bleaching in 2016, 2017 and 2020

As a fabled wonder of the natural world, Australia’s Great Barrier Reef and its diversity of marine life ranging from corals to whales found a place on UNESCO’s World Heritage List in 1981. Made up of a couple of thousand individual reefs off the continent’s northeastern coast, it has a geological history going back an estimated 23 million years to the Miocene epoch, and has survived many challenges.

The GBR is about 2,300 km long and extends across a breathtaking 346,000 sq. km. area, hosting an assemblage of fishes and invertebrates in the reefs, dugongs, green turtles and other species in seagrass meadows, and sharks, rays, anemones, sponges, worms and myriad other forms all of which need a delicate ecological balance to thrive.

Idyllic as it appears, the reef system faces severe environmental threats, and this year, the World Heritage Committee has sounded a warning by drawing up a resolution to inscribe the reef on the ‘List of World Heritage in Danger’. The Committee took note of the 2019 Outlook Report of the Great Barrier Reef Marine Park Authority, which says in no uncertain terms that the long-term state of the ecosystem has further deteriorated from poor to very poor. At the heart of the crisis is climate change, which has led to three big events of coral bleaching in 2016, 2017 and 2020. UNESCO’s move to list the GBR as ‘in danger’ brings pressure on Australia’s governmentto review its record on responding to climate change. As a continent that has recorded a rise in its average temperature by 1.4 degrees C since 1910, the devastating fires of 2019-20 were another wake-up call on climate change aggravating extreme events.

Destructive impacts

The World Heritage Committee resolution calls upon Prime Minister Scott Morrison’s government to heed the conclusions of the Outlook Report, particularly on accelerated action needed to address climate change with the Paris Agreement goals in focus. The updated Reef 2050 Plan that the country is pursuing for conservation should incorporate this. Further, the government should stop destructive impacts of human activity such as land-based and farm run-off that has polluted waters, coastal development and other commercial uses, it adds.

The World Heritage Centre, the administrative body, had sent a letter to Australia in 2019 raising concerns “about the approval of the Carmichael Coal Mine”, a controversial project with impacts for the reef and the climate, to which it got a response noting “that the project’s approval is subject to over 180 regulatory conditions and that compliance with these conditions will be monitored.”

Canberra’s response to the UNESCO Committee’s move was to allege a conspiracy, hinting at pressure from China, which holds the chairmanship of the panel.

Close scrutiny of the GBR shows a variety of ecological impacts from environmental stresses, including climate change. The Outlook Report records harm to “the abundance and health of many species groups, including corals, invertebrates, some bony fishes, marine turtles and seabirds” from the rising sea temperatures and thermal extremes due to global warming. It adds that since 2014, there has been widespread and significant declines in many coral species. In 2018, coral larvae declined by 89% averaged across the region, arising from consecutive bleaching events, as the adult broodstock was reduced.

Warmer temperatures led to “feminisation of green turtles originating from nesting beaches in the northern Region, potentially leading to significant scarcity or absence of adult males in the future”. Coral growth is also endangered by the proliferation of crown-of-thorns starfish, which consumes them.

Some relief is available from the reported recovery of humpback whales, and slow gain in southern populations of green turtles. Urban coastal dugong populations also show an improved breeding rate. But overall, the reef is under threat.

A magnet for eco-tourists, the vast expanse coloured by algal hues draws thousands annually. The report says that in 2015-16, tourism, fishing, recreational uses and scientific activities contributed an estimated $6.4 billion to the Australian economy, a rise of about 14% since 2011-12. Without resolute action on climate and pollution threats, though, all sectors stand to lose.