Imagine the possibilities. One could provide us with an unlimited source of green and safe energy. The second could improve the world’s sustainability by making electricity grids efficient while cutting down transmission and distribution losses massively. In the medical field, the first of the two discoveries could give the world an effective cure for one of the most fearsome diseases known to humans—cancer. The fourth discovery is about controlling Alzheimer’s, a disease that slows down man’s cognitive and functional performance. Currently, it has no cure or disease-modifying treatment.
All these discoveries come with challenges. They need to be replicated and pass peer review. In the case of medical discoveries, they need to clear clinical trials, and the benefits they eventually offer should far outweigh their side-effects. But the scientific community appears excited. Scientists are also sceptics. They have begun looking at these claims closely. A few may fail to make the cut but as Albert Einstein said, “failure is success in progress”.
Nuclear fusion
On 30 July, researchers at the National Ignition Facility, located at Lawrence Livermore National Laboratory, California, announced that they had achieved net energy gain in a fusion reaction. In other words, they managed to generate more energy than what the process consumed.
This was the second time they did so—the facility achieved this feat earlier in December last year. Most importantly, the quantum of net gain was higher now. Net energy gain is critical to make commercial fusion power possible. That possibility has kindled hopes even among policy makers. Jennifer Granholm, the US energy secretary, said this success was “one of the most impressive science feats of the 21st century”.
Ever since German scientists Otto Hahn, Lise Meitner and Otto Frisch successfully split the Uranium atom in December 1938, nuclear fission has seen significant progress, both for building weapons and peaceful purposes. As captured in the recent Christopher Nolan blockbuster Oppenheimer, the US government moved fast to weaponize nuclear fission, a process where a heavier atom is split into smaller ones which results in a massive release of energy. In 1945, the Second World War was on its last legs. Germany was defeated but Japan was yet to give in. Americans felt that an atomic bomb would decisively tilt the balance. The bomb was tested in July 1945; Hiroshima and Nagasaki were bombed in August. The war came to an end.
Nuclear fission was first used for peaceful purposes—to generate electricity— only in December 1951. Today, there are over 440 nuclear reactors in operation around the world generating as much as 10% of electricity that is produced.
But when it comes to nuclear fusion—a process by which two lighter atoms are fused together to produce a heavier atom, resulting in the release of massive energy —the progress has been slow. Like nuclear fission, nuclear fusion does not emit any greenhouse gases. But unlike fission, fusion leaves no radioactive waste and produces a lot more energy with a lot less fuel.
The raw material to produce energy through nuclear fusion is hydrogen and is available in abundance. Nuclear fission, on the other hand, uses uranium which needs to be mined and is not an infinite resource. Nuclear fusion could therefore solve humanity’s quest for unlimited sustainable energy.
Ironically, nuclear fusion was also weaponized first. The US tested the first hydrogen bomb (it was 10 times more powerful than the bombs dropped in Japan) in 1952. However, efforts to harvest fusion for peaceful use did not take off as energy required for the fusion reaction was more than it generated. This is because of what scientists call the Coulomb Barrier. For a fusion reaction to take place effectively, two positive nuclei have to come close to each other. But two positive nuclei repel each other—this phenomenon is called the Coulomb Barrier. To overcome this barrier and get the nuclei to come closer, a large quantum of energy is required. It took scientists over 70 years to ensure that the energy produced is more than what is expended to make the reaction possible.
In the December experiment, the energy produced was 3.15 megajoules as against 2.05 megajoules that was spent. Initial analysis of the July test data reveals that the net gain was even higher. Megajoule is a unit of energy measurement.
“Achieving net energy gain in nuclear fusion is more than just a necessity to guarantee a safer and sustainable planet for the future generations. Fusion power is probably the only large-scale solution that could save the planet from irreversible damage that it is undergoing due to usage of fossil fuels and greenhouse gas emissions,” says Ratna Kumar Annabattula, professor at the department of mechanical engineering, IIT Madras.
But there is still some way to go before commercial power is generated from fusion reactions. For one, practical fusion reactors have not been built yet. Containing plasma at fusion temperature (hot gas tends to expand and escape from enclosing magnetic structures) is still a challenge. Robert W Conn, a plasma physicist put it succinctly when he wrote in an article recently: “The quest for practical fusion energy remains one of the greatest scientific and engineering challenges of humankind”.
Room temp superconductivity
On 22 July, South Korean researchers—among them were Sukbae Lee, Ji-hoon Kim and Young-wan Kwon— published two papers in arXiv, a physics site, claiming to have successfully developed a substance that achieved superconductivity at room temperature. Superconductivity is a phenomenon where a substance offers zero or near zero resistance to electricity.
The substance, LK-99, was a combination of copper, lead, phosphorus and sulphur—substances that were both cost-effective and easily available. The claim, therefore, generated both excitement and scepticism.
It is not the first-time scientists have achieved, or have claimed to have achieved, superconductivity. In 1911, Dutch physicist Heike Kamerlingh Onnes successfully achieved superconductivity in mercury. He did so at an extremely low temperature of –269 degree centigrade. Over the years, other conductors displayed superconductivity but at extremely low temperatures. Aluminium exhibited superconductivity at –271.95 degrees, zinc at –272.3 degrees, tin at —269.95 degrees, lead at –265.95 degrees and titanium at –272.76 degrees. Scientists have even identified materials that displayed superconductivity at 7 degrees centigrade but at very high pressure. But at such low temperature and high pressure, their practical utility is limited.
This is where the findings of South Korean researchers are significant. They claim to have developed a material that exhibits superconductivity at room temperature and ambient pressures.
This, if confirmed, will have a significant impact on how the world operates. Take the case of power transmission. The world uses copper and aluminium for building transmission lines but at ambient temperatures they exhibit resistance to electricity. This results in transmission and distribution (T&D) loss. In the US alone, 100 billion units of electricity are wasted every year in T&D losses.
“Superconductivity at room temperature will have a profound implication,” says G Baskaran, distinguished professor at the department of Physics, IIT-Madras. “We can have a very efficient electric grid that causes almost no T&D loss. The field of medical imaging will get a big fillip with magnetic resonance imaging (MRI) machines becoming more efficient and super cheap. Also, transportation will see a major transformation. Magnetic levitation trains will connect various parts of the world, cutting down travel time significantly,” he adds. It will also become easier to build a nuclear fusion reactor.
Nonetheless, this is not the first time that such a claim has been made.
In 2018, scientists at the Indian Institute of Science (IISc) made a similar claim. They developed a material—a silver and gold mixture—which they said displayed superconductivity at ambient temperature and pressure. But they could not replicate the success. “The IISc researchers are still at work to stabilize the outcome,” says Baskaran.
Then, in 2020, a few American physicists made a claim of superconductivity at 15 degrees centigrade but they had to withdraw it. Many experts are already questioning the claims made by the Korean researchers. They say LK-99 may just be a magnet and not a material that displays superconductivity at room temperature. The jury is still out.
“The challenge here is to replicate the success. These are nanoscale phenomenon, and you have no control over them. A substance may show superconductivity once but will not do so again,” says Baskaran.
Cancer-killing pill
On 1 August, City of Hope, one of the largest cancer research and treatment organization in the US, published a study in a peer-reviewed academic journal about an experimental anti-cancer molecule that kills cancer cells without affecting the healthy ones. The molecule, AOH1996, is named after Anna Olivia Healey—born in 1996, she died of cancer in 2006. The funds collected by her parents helped support the development of this molecule.
The molecule targets the proliferating cell nuclear antigen (PCNA) protein, which plays a critical role in DNA replication. Till recently, PCNA was considered difficult to target using medicines. It took a team in City of Hope, under professor Linda Malkas, two decades of research and extensive computer modelling, one that involved simulating and analysing the interactions between millions of different molecules, to come up with a molecule that could target cancer-affected PCNA.
When a patient is afflicted by cancer, the PCNA is uniquely altered in the cancer cells. It is these mutated PCNA cells that multiply rapidly leading to the spread of cancer and the patient’s eventual death. AOH1996 targets only the mutated PCNA cells and prevents them from dividing and making a copy of the faulty DNA. Its unique selective mode of action, where only the cancer cells are targeted, spares the healthy cells. In most therapies, no difference is made between good cells and bad cells.
In a study published in Cell Chemical Biology, a journal, Malkas has claimed that in pre-clinical studies, AOH1996 has been effective against breast, prostate, ovarian, cervical, skin, brain and lung cancers. “Results are promising and AOH1996 can suppress tumour growth as a monotherapy or combination treatment in cell and animal models without resulting in toxicity,” Malkas said while speaking to the media post submission of the paper. Phase-1 clinical trials began in October at City of Hope.
This discovery surely has given hope to thousands of cancer patients and their families across the world.
Hope for the elderly
Alzheimer’s is the most common problem that affects the elderly. The disease kills the memory and thinking cells in the brain and leads to progressive declining in cognitive and functional ability of those affected. Despite its prevalence among the elderly and billions of dollars invested so far, currently, there is no cure or even a disease modifying treatment for Alzheimer’s.
“All these years, what we offered was a symptomatic treatment which provided some relief to patients who were in the initial stages of the disease,” says Dr P Vijayashankar, a senior consultant neurologist at Apollo Hospitals. That could change with Donanemeb, a drug developed by Eli Lilly & Co.
The drug mops up amyloids or plaques that accumulate in the brains of people with Alzheimer’s and slows down the progress of the disease. In the phase-3 clinical trials involving 1,736 participants in the 60-85 years age group with early symptomatic Alzheimer’s disease, 36% showed decline in 18 months.
“This is the first time such a medicine that slows down cognitive and functional decline in people with early symptomatic Alzheimer’s disease has been found,” says Vijayashankar. It has the potential to significantly improve the quality of life of the patients and provide much needed respite to the caregivers, he adds.
But what is worrying the doctors is the potential side effects of the drug. During the trials, the drug caused brain swelling (ARIA-edema) in 24% of the cases and haemorrhaging (ARIA-H) in 31% of the cases. That apart, patients in the trial suffered from headaches, confusion, vomiting and seizures.
“The side effects are worrying but this is just a starting point. All these years we knew nothing about slowing the disease. Today, thanks to this drug, we have something to start with,” says Vijayashankar.
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Updated: 15 Aug 2023, 10:12 PM IST
