Tag a turtle to catch a cyclone
A project that tags turtles to track sub-sea conditions for cyclone prediction
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Precious superconductor
‘Superconductivity’ is the holy grail of electrical physics — current zips through superconducting wires, with no loss of energy. In conventional electricity conduction, some amount of electrical energy gets converted into heat due to the resistance offered by the conducting material.
If our power lines were made of superconducting materials, it would mean phenomenal savings. But superconducting materials work only in ultra-cold conditions.
The need is for superconducting materials that work in ambient temperatures.
The Indian Institute of Science (IISc) has achieved a breakthrough with an engineered material they call ‘Au-Ag Nanostructures’. Silver particles, a billionth of a metre in size, are embedded into lattice structures of gold atoms. It shows “superconductivity-like signatures” because it offers zero resistance to the flow of electrons, Prof Anshu Pandey of the institute’s solid state and structural chemistry department told Quantum.
But to qualify fully as a ‘superconductor’ it would need to have a few other properties.
The biggest of these is ‘stability’. The material is “extremely unstable”, meaning it does not remain unchanged for long. The researchers struggle to produce enough even for testing. Pandey is optimistic of tackling this problem within “10-12 months”.
IISc is inviting industry to partner in this research.
Published on
July 24, 2022
Why the anti-ageing market is only skin-deep
We are living in an ageing world. The number of people older than 65 is inching towards the one-billion mark. Not everyone’s thrilled about this, of course — so we have a big and growing market for anti-ageing products (expected to grow from $60.42 billion in 2021 to $120 billion by 2030). Are they safe?
A recent paper titled ‘Nicotinamide mononucleotide (NMN) as an anti-ageing health product — Promises and safety concerns’, published by a group of researchers from China and New Zealand, has raised several concerns.
We age because of a process called ‘mitochondrial decay’. Mitochondria are part of our cells and responsible for producing energy, hence they are the ‘powerhouses’ of our bodies.
Over time, mitochondria are unable to produce enough energy since there is a dip in the levels of a biochemical called nicotinamide adenine dinucleotide (NAD+) in them; this happens because the NAD+ are consumed by enzymes such as NADase and sirtuins. Depletion of NAD+ is also associated with oxidative stress, DNA damage, and cognitive impairments.
The trick in anti-ageing is, therefore, to keep NAD+ levels steady. Now, NAD+ is derived from another chemical called nicotinamide mononucleotide (NMN), which is a bioactive nucleotide formed when a nucleoside comprising nicotinamide and ribose reacts with a phosphate group.
Profit over safety
NMN can be industrially produced as a food supplement that brings several benefits in addition to anti-ageing — it helps combat obesity and associated complications, Alzheimer’s disease, cerebral and cardiac ischemia, and type-2 diabetes, note the authors of the paper.
These days, NMN products are marketed as supplements for anti-ageing and longevity in the form of capsules with dosages exceeding 500 mg. The safety of these doses cannot be assessed since there have been no clinical or toxicological studies.
“Excessive demand of consumers and high profit margin for manufacturers are the major driving force behind the release of anti-ageing health products without adequate safety testing,” the paper says. There is no regulatory authority for NMN products as they are often sold as a food product rather than heavily regulated therapeutic drug.
Published on
July 24, 2022
Uprooting cancer
Many cancer patients get cured and then have a relapse.
What causes this are the ‘cancer stem cells’ (CSC). Many of us are familiar with stem cells from cord blood, which, if preserved, can be used to regenerate body parts such as a damaged organ or a broken bone. CSC are similar — they help in generating cancer cells.
Drugs find it hard to eliminate CSC, because they proliferate rapidly. You would need to find out how they do that, so you can attack the root of the problem.
Two Indian medical researchers, Dr Arun Dharmaraj and Dr Shobha Warrier, have achieved this. Dharmaraj, who has held academic positions at Johns Hopkins School of Medicine, Baltimore, USA, and The University of Western Australia, Perth, is currently Vice-Principal of the Faculty of Biomedical Sciences and Technology, Sri Ramachandra Institute of Higher Education, Chennai. Dr Warrier is Dean and Professor, Manipal Institute of Regenerative Medicine, Bengaluru. Together they have discovered a ‘small molecule drug’, which they call SC501, to target CSC. ‘Small molecule drugs’ are a class of drugs that can easily enter a cell; pharma companies make them for targeted therapies.
Earlier, Dharmaraj had done research in an area called ‘wnt signalling’. In cell biochemistry, ‘signalling molecules’ convey genetic information from one cell to another.
These molecules may be simple gases or complex proteins. Some latch on to ‘receptors’ on the cell wall; others are capable of entering cells and latching on to receptors in the cytoplasm or on the wall of the nucleus. They pass on genetic information from one cell to another, much like saying, “Here, take this and make a thousand copies, and be quick.”
In a 2020 paper, ‘Biology and Enhancement of Skeletal Repair’, Dr Bruce Browner, et al, note that “wnt proteins form a family of highly conserved secreted signalling molecules that regulate cell-to-cell interactions”.
Now, CSC proliferate using the wnt pathway. Dharmaraj had earlier discovered that CSC using wnt proteins “are over-expressed”. Later, he and Dr Warrier developed the small molecule SC501, which, rather than attack CSC, guns down the wnt pathways to inhibit the growth of cancer cells. In other words, the small molecule is a ‘wnt inhibitor’; by destroying a feature specific to CSC, namely the ‘wnt pathway’, the molecule prevents the stem cells from increasing their tribe.
In addition, the SC501 starves cancer cells of blood by preventing angiogenesis or development of new blood vessels that supply to them. This it does by blocking a protein responsible for angiogenesis.
Dharmaraj and Warrier have applied for patent for SC501 and do not wish to divulge much about the compound, except to say that it is not a biomolecule. Dharmaraj calls it a “magic molecule” because it can potentially be used in the treatment of many other diseases, such as osteoporosis, diabetes and even neuro-degenerative ailments.
The researchers stress that SC501 is still in “pre-clinical stage”. It has to be produced in enough quantities for clinical trials before heading to mass production. For this, they are mulling a pilot plant, which could cost ₹1 crore.
Published on
July 24, 2022
Affordable hi-res thermal cameras
Researchers have developed an algorithm that can make high-resolution thermal cameras affordable for the masses. While visible-range cameras have become common, thermal cameras still cost a premium. Thermal cameras, which capture the scene temperature in the far-infrared region, find specialised use in fields such as the military, surveillance, firefighting, automation, and pedestrian tracking.
At present, low-resolution thermal cameras are available at affordable prices, but the image captured is very small and barely usable. A positive aspect is that these cameras usually come with a high-resolution visible-range camera, similar to smartphones. As such, guided super-resolution techniques can be used to create an illusion of a high-resolution thermal camera. The biggest challenge here is that the captured low-resolution thermal images are not aligned with the high-resolution visible images. There is a pixel-to-pixel misalignment.
Feature-based matching techniques fail for thermal-visible image pairs because of the difference in the spectral ranges. A group of IIT-Madras researchers, led by Dr Kaushik Mitra, Assistant Professor, Department of Electrical Engineering, have resolved this problem by developing two algorithms to correct the misalignment. The research has the potential to help increase the reach of thermal imaging technology to general consumers. It provides a direct solution for improving the quality of thermal camera outputs, making it more accessible and affordable, according to a press release.
Antibiotic adjuvants
Scientists at Jawaharlal Nehru Centre for Advanced Scientific Research, Bengaluru, have come up with a method of revitalising the efficacy of antibiotics by using them in combination with antibiotic adjuvants — ingredients that help counter resistance to the antibiotics. This can help strengthen and bring back obsolete antibiotics for treating complicated infections — effectively countering the rising menace of anti-microbial resistance.
Geetika Dhanda and Prof Jayanta Haldar incorporated cyclic hydrophobic moieties (portion of a molecule) in a triamine-containing compound; the adjuvants thus developed “weakly perturbed the membrane of bacteria”, says a press release. This resulted in countering membrane-associated resistance elements like permeability barrier and expulsion of antibiotics by efflux pumps.
The combination of the adjuvant with antibiotics like fusidic acid, minocycline, and rifampicin inactivates multidrug-resistant Gram-negative bacteria such as Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacteriaceae. The choice of non-active adjuvant would also put less pressure on the bacteria to develop resistance to it. Moreover, weak membrane perturbation would result in less toxicity.
Published on
July 24, 2022
Five images and a million new questions
The first five images sent by NASA’s James Webb Space Telescope created a buzz of excitement among scientists, astronomy enthusiasts, and laypeople alike. One of them, a deep-field image of a galaxy that is five billion light years away, shows in the background other galaxies that are 13 billion light years away, very close to the beginning of the universe and time. Then there are images of an exoplanet, a planetary nebula, a cluster of five galaxies called ‘Stephan’s Quintet’, and a galaxy called Carina. The infrared telescope has since sent a few more images — grist for further research. To make better sense of all this, Quantum spoke with Dr Dipankar Bhattacharya, Professor of Astrophysics at Ashoka University, Delhi. Excerpts:
We have seen a lot, but have we learnt anything new?
Let me first say that these pictures are samples to demonstrate what the Webb can do. Research and learning will follow. If you take the deep-field image, with a telescope like the Hubble, it would take a month-long exposure to get pictures of lesser resolution and depth; with the Webb, it was just half-a-day.
We have been able to see galaxies that are 13.1 billion light years away. We have seen objects in a very early stage of evolution. However, we have also learnt quite a lot. For example, we have spectrally imaged an exoplanet and found there is water vapour in its atmosphere. We have learnt that in the centre of the planetary nebula, there are two stars, not one — one dying and the other in an early stage of evolution. This will lead to further studies. We have seen an infrared jet in one of the galaxies in Stephan’s Quintet, which leads to the inference that there is some material being ejected from around a black hole at the centre of the galaxy, from just outside the event horizon.
So, yes, we have seen a lot and also learnt a lot.
How far back in time will the Webb be able to see?
Right now, the galaxy spectra Webb has released go up to 5 microns (wavelength), but it is designed to go up to 28 microns. Our current theory says that the first light-emitting object will be within the 28-micron range. You don’t need to go any further. We can do spectroscopy of the very first light-emitting object. From a red shift of 1,100 till about 20, the universe was just neutral gas, no luminous object, so nothing was emitting light.
Can you please explain what is ‘red shift of 1,100’?
Red shift of 1,100 means that the universe was 1,101 times smaller than now. Similarly, red shift of 20 means, 21 times smaller than now.
So, the universe began emitting light from the time the red shift was around 20?
Yes. Before that it was dark.
How long ago was that?
About 200 million years after the big bang.
Then, is it not possible to look deeper into the past?
You cannot look deeper using infrared. From red shift of 20 to, say, 1,100, you would need radio telescopes. The Square Kilometer Array Observatory intends to do that.
And beyond red shift of 1,100?
Before the red shift of 1,100 the universe was opaque to electromagnetic radiation.
So, you can never ‘see’ the first few seconds after the big bang or the big bang itself?
It is not possible with electromagnetic radiation. You would have to look for particulate radiation, perhaps neutrinos, or gravitational waves.
For infrared, Webb is the best we have?
Yes, unlike other telescopes, the Webb can see through dust. That is how we are able to see into the planetary nebula (catalogued NGC 3132), which is about 2,500 light years away.
Planets form in very dusty regions, so if you want to probe the early stage of formation of stars, you have to look inside the dust cloud. Unless you go to long wavelength infrared, you would never be able to do that. Webb has the capability to penetrate dust clouds and look at newly forming stars.
Like the one in the middle of the nebula?
Exactly. It was never seen before. Also, in the planetary nebula picture, you see the second star — the star from which matter has been ejected to form the nebula. Only in the MIRI picture (taken by the mid-infrared instrument in the Webb) do you see the second star.
Which is the dying star?
Yes, it is the dying star that has caused the nebula. The other is in an early stage of evolution.
What are we seeing in Stephan’s Quintet?
The Stephan’s Quintet picture really demonstrates Webb’s capabilities. It is not one picture, but a thousand exposures, from different positions, stitched together to form a wide-field image. In the topmost galaxy there is a vertical line, a jet emanating from the centre of the galaxy. It means there is some material being ejected from around the black hole there. Webb has also measured the spectrum of the gas surrounding the black hole, which is a first. That will tell us the composition of the material.
Webb is an infrared telescope. Then, how are we getting these pretty pictures, as though taken by an optical camera?
Basically, it is an artist-like job. You see how intense the radiation is and from which part of the image. Then you ‘assign’ different colours for different intensities, or for different wavelengths. So, you build up an image that looks like a photograph.
