MAY 3rd Current Affairs

1. Pressure Swing Adsorption (PSA) Oxygen

IN NEWS:

PM reviewed progress on setting up of PSA plants. He was informed that around 1500 PSA plants are in the process of being set up through the contribution of PM CARES, PSUs and others. He directed officials to ensure the speedy completion of these plants.

KEY POINTS:

The technology

• Adsorption is defined as the affinity of fluid for a solid surface. Using the differential affinities of various components of a gas mixture (such as air) it is possible to separate the various components. That, essentially, is the principle used by a PSA oxygen plant.
• Such a plant can come in varying capacities to generate oxygen. It employs a technology that absorbs nitrogen from ambient air to concentrate oxygen for supply to hospitals or the industry, as the case may be.
• They operate at near-ambient temperatures and use specific adsorbent materials like zeolites, activated carbon, molecular sieves etc., to trap oxygen at high pressure.
• The oxygen thus generated can be supplied straight to the site of use either through a dedicated pipeline or compressed to fill cylinders.
• While the oxygen produced by these plants is believed to be less pure than liquid oxygen derived from cryogenic technology, the outrage in the country currently centres around the debate about whether these plants could have helped ease the ongoing medical oxygen crisis.
• Medical grade oxygen has an oxygen concentration between 90.0 per cent and
• 96 per cent. The remainder is principally argon and nitrogen.

Advantages of PSA plant

• There are two obvious advantages of the technology — the first is that the hospital gets a captive plant that can generate all the oxygen it needs, doing away with the need for cylinders etc. As the home ministry said Monday, India’s problem is not oxygen generation but oxygen transportation.
• Handling cylinders also has a safety aspect to it as oxygen under high pressure is highly inflammable. Several fires in Covid-19 hospitals across the country in the last few days have been grim reminders of those risks.
• The plant can also give it some buffer during times of augmented demand. It is not an expensive technology.
• But what works very well for hospitals also is the fact that PSA is ‘clean technology’. The raw material that it uses is the ambient air. It also takes very limited space; the maximum area occupied by a PSA oxygen plant is about 7ft/9ft/7ft.
• It takes just a few weeks to get a plant up and running and there are at least 25 vendors in the country who can supply between 2-20 plants per month.

SOURCE:TH

2. Climate Change Causing Shift in Earth’s Axis

IN NEWS:

• A study published in Geophysical Research Letters of the American Geophysical Union (AGU) says that due to the significant melting of glaciers because of global temperature rise, Earth’s axis of rotation has been moving more than usual since the 1990s.
• While this change is not expected to affect daily life, it can change the length of the day by a few milliseconds.

KEY HIGHLIGHTS:

Findings from the New Study:

• Since the 1990s, climate change has caused billions of tonnes of glacial ice to melt into oceans. This has caused the Earth’s poles to move in new directions.
• The north pole has shifted in a new eastward direction since the 1990s, because of changes in the hydrosphere (meaning the way in which water is stored on Earth).
• From 1995 to 2020, the average speed of drift was 17 times faster than from 1981 to 1995.
• Also, in the last four decades, the poles moved by about 4 metres in distance.
• The calculations were based on satellite data from NASA’s Gravity Recovery and Climate Experiment (GRACE) mission.

Causes of Polar Drift:

Ice Melting:

The faster ice melting under global warming was the most likely cause of the directional change of the polar drift in the 1990s.

As glaciers melt, water mass redistributes, causing shifts in the planet’s axis.

Change in Non-Glacial Regions (Terrestrial Water Storage):

Due to climate change and unsustainable consumption of groundwater for irrigation and other anthropogenic activities.

Groundwater Depletion:

As millions of tonnes of water from below the land is pumped out every year for drinking, industries or agriculture, most of it eventually joins the sea, thus redistributing the planet’s mass.

SOURCE:IE.

3. Coronavirus: What are variants of concern?

IN NEWS:

Variants of concern, widespread relaxation of COVID-19 appropriate behavior have kicked off new waves of transmission.

KEY POINTS:      

Keeping track: Why So many mutations

• Detecting variants relies on whole genome sequencing. Globally, over 1 million SARS CoV-2 genomes have been sequenced to date.
• If manuscripts are copied by hand repeatedly, spelling errors are common.Similarly, when ‘genetic scripts’ encoded in DNA or RNA are copied repeatedly for virus replication, errors do occur.
• RNA viruses are more error-prone than DNA viruses. SARS-CoV-2 genome is single-stranded RNA, and errors — in biology, mutations — occur frequently.
• SARS-CoV-2 is new in humans and as it spreads, mutations are very frequent.Emerging variants with higher transmission efficiency become dominant, tending to replace others.
• Such frontrunners emerge in different geographic communities where the virus is epidemic, spreading widely. Variants were detected in the U.K. and South Africa because genetic studies were systematically done. Brazil variant was discovered in Japan, in travellers from Brazil, and its origin traced back.

The Indian SARS CoV-2 Genomic Consortium (INSACOG)

• As the importance of ‘variants of concern’ (VOC) was appreciated, the Indian SARS CoV-2 Genomic Consortium (INSACOG), a network of ten competent public-sector laboratories for genomic surveillance, was established, and the genetic variant landscape is being surveyed in India.
• There are three different schemes of nomenclature of SARS-CoV-2 variants. The widely used one is the ‘Phylogenetic Assignment of Global Outbreak Lineages’ (PANGOLIN) that uses a hierarchical system based on genetic relatedness – an invaluable tool for genomic surveillance. It uses alphabets (A,B, C, P) and numerals starting with 1.
• Variant lineages are at the emerging edge of the pandemic in different geographies. Lineage B is the most prolific. The variants in circulation are B.1; B.1.1; B.1.1.7; B.1.167; B.1.177; B.1.351, B.1.427 and B.1.429. Lineage P.1 has deviated from the original B.
• For convenience, the three most frequent ones are named by their geography of origin — ‘U.K. variant’ for B.1.1.7; ‘South Africa variant’ for B.1.351; and ‘Brazil variant’ for P.1.
• 5. Variants in India include the so-called double mutant B.1.617 spreading in Maharashtra and B.1.618 spreading in West Bengal.

Matters of concern

• The ‘concern’ in VOC comprises three sinister properties – transmission efficiency, disease severity and escape from immunity cover of vaccination.
• Fortunately, mRNA (Pfizer and Moderna) vaccines have broader immunity for different reasons, and they protect better against these two variants.

Lessons learnt

• An important lesson the pandemic has taught us in India is the critical importance of biomedical research and capacity building – for saving lives and economic growth.
• We need a foundation of broad-based research, in universities, medical colleges and biotechnology companies, all of which must be funded, encouraged, appreciated, and talent rewarded.
• While some endeavours have been initiated, they must take off in a big way, and India must invest heavily in biosciences. After a decade, its products and profit will make us healthier and wealthier.

SOURCE:TH

4. Xylophis deepaki

IN NEWS:

• A tiny snake “Xylophis deepaki” has been named in honour of Indian herpetologist Deepak Veerappan for his contribution in erecting a new subfamily Xylophiinae to accommodate wood snakes.
• The common name suggested for the species is ‘Deepak’s wood snake’.

KEY TAKEAWAYS:

• In the first four months of 2021, the Western Ghats presented new butterflies, frogs, fruit flies, and even a freshwater crab.
• Joining the list is a tiny snake of just 20 cm length with iridescent scales – Xylophis Deepaki.
• It was first stumbled upon in a coconut plantation in Kanyakumari.
• It is now reported to be an endemic species of Tamil Nadu and has been sighted in a few locations in the southern part of the Western Ghats.
• The species is named in honour of Indian herpetologist Deepak Veerappan for his contribution in erecting a new subfamily Xylophiinae to accommodate wood snakes.

Important Information:

• Wood snakes are harmless, sub-fossorial and often found while digging soil in farms and under the logs in the Western Ghat forests.
• They feed on earthworms and possibly other invertebrates.
• Interestingly, their close relatives are found in northeast India and Southeast Asia and are known to be arboreal.

SOURCE:TH