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How to Fix Arthritis in Damaged Knee

By stimulating cells to reproduce, electricity has already been shown to help heal soft tissue injuries. Now, an electricity-producing implantable material likewise appears to boost the regrowth of cartilage in compromised joints. In a study conducted at the University of Connecticut, a team led by Asst. Prof. Thanh Nguyen and postdoctoral fellow Yang Liu explored the use of a “tissue scaffold” made out of nanofibers of a biodegradable polymer known as poly-L lactic acid (PLLA). It had previously been used to accelerate the healing of broken bones.

So-called tissue scaffolds take their name from the fact that they have a scaffolding-like three-dimensional internal structure, which acts as a sort of roosting place for adjacent cells to migrate into and reproduce. Eventually, the scaffolding dissolves and is replaced entirely by the cells, resulting in a solid piece of biological tissue.

Unfortunately, according to the scientists, joint cartilage that has been regrown using conventional scaffolds has tended to be weaker than the original cartilage, causing it to quickly break down under regular use. That’s where the PLLA comes in. Along with being biocompatible, it’s also a piezoelectric material, meaning that it produces a small electrical current when mechanically stressed. Therefore, it was believed that if a tissue scaffold made of the material were to be implanted in an arthritic knee joint, it would continuously produce cartilage-boosting electricity as it was squeezed during activities such as walking. In order to test that theory, pieces of the material were placed in the injured knee joints of rabbits, which regularly hopped on a slowly-moving treadmill. It was found that after one to two months, strong, robust cartilage proceeded to grow back within the joints. By contrast, a control group that received non-piezoelectric tissue scaffolding experienced little healing of the damaged cartilage.

Importantly, the material didn’t contain any chemical growth factors, which may cause unwanted side effects. The researchers now want to test the technology on larger, older animals, and to monitor the regrown cartilage for at least a year or two.

Source: https://today.uconn.edu/

Super-Speedy Diagnosis of Rare Genetic Diseases

About a year ago, Matthew Kunzman’s heart was failing, despite doctors’ best attempts to bolster it with every pump and gadget they could think of. But the 14-year-old has bounced back in large part due to super-speedy genetic sequencing that pinpointed the cause of his disease and helped doctors decide how to treat it — in just 11 and a half hours. That speedy diagnosis — faster than any other medical team has previously reported — resulted from a new approach to DNA sequencing to help patients with deadly and rare diseases. On Wednesday, a team of Stanford researchers and collaborators published a letter in the New England Journal of Medicine reporting that they had sequenced 12 seriously ill patients and successfully diagnosed five of them (including Matthew). In all five cases, the information led to tangible changes in how patients were treated.

Typical turnaround time for diagnosis was around eight hours and as short as seven hours and eighteen minutes – less than half the current record. And the scientists are convinced they can cut that in half yet again. Such speed could be life-saving for critically ill patients, according to Euan Ashley, a Stanford cardiologist and the study’s senior author.

You can not only make care better, and help patients more, but do it cheaper, save money, save the system money,” Ashley said. “It seems like a win, win, win all around.”

There’s a lot to be learned by exploring your genetic code, which influences everything from your height and eye color to your likelihood of developing certain diseases. For doctors, knowing whether a patient’s symptoms are linked to specific DNA mutations — and, if so, which ones — can help them determine what treatments and surgical procedures to try and which ones to avoid. But it typically takes weeks to run, process, and interpret sequencing results. That’s time some patients don’t have. And hospital stays spent chasing down the cause of an unknown disease can cost tens of thousands of dollars.

Ashley wanted to see how quickly he could speed things up. He and his team enrolled a dozen seriously ill patients admitted at Stanford, taking about half a teaspoon of blood from each of them for genetic sequencing. The participants, who ranged in age from 3 months to 57 years old, suffered from everything from seizures to cardiac arrest. Throughout the six-month study, which kicked off in December 2020, researchers tweaked nearly every step of the sequencing process, from having someone run samples from the hospital to the lab to shortening the time needed to prep DNA for sequencing. It was round-the-clock work.

Source: https://www.statnews.com/

Artificial Molecule With Superpowers

When scientists discovered DNA and learned how to control it, not only science but society was revolutionized. Today researchers and the medical industry routinely create artificial DNA structures for many purposes, including diagnosis and treatment of diseases. Now an international research team reports to have created a powerful supermolecule with the potential to further revolutionize science. The work is published in Nature Communications . Authors are from University of Southern Denmark (DK), Kent State University (USA), Copenhagen University (Denmark), Oxford University (UK) and ATDBio (UK). Lead authors are Chenguang Lou, associate professor, University of Southern Denmark and Hanbin Mao, professor, Kent State University, USA.

The researchers describe their supermolecule as a marriage between DNA and peptides

DNA is one of the most important biomolecules, and so are peptides; peptide structures are used, among other things, to create artificial proteins and various nanostructures. If you combine these two, as we have, you get a very powerful molecular tool, that may lead to the next generation of nanotechnology; it may allow us to make more advanced nanostructures, for example, for detecting diseases, says corresponding author Chenguang Lou, associate professor at Department of Physics, Chemistry and Pharmacy, University of Southern Denmark. According to the researchers, another example is that this marriage of peptides to DNA can be used to create artificial proteins, which will be more stable and thus more reliable to work with than natural proteins, which are vulnerable to heat, UV, chemical reagents, etc.

Our next step will be to investigate whether it can be used to explain the cause of Alzheimer’s disease in which malfunctional peptides are culprits, says the other corresponding author, Hanbin Mao, professor at Chemistry and Biochemistry, Kent State University. The research work reports the mechanical properties of a new structure composed of three-stranded DNA structures and three-stranded peptide structures. It may sound simple, but it is far from. It is rare in Nature that DNA and peptide structures are chemically linked like this new structure is. In Nature, they often behave like cats and dogs, though some key interactions are essential to any living organisms. One possible reason for this is their so-called chirality – sometimes also described as handedness.

All biological structures, from molecules to the human body, have a fixed chirality; think of our heart, which is always positioned in the left side of our body. DNA is always right-handed and peptides are always left-handed, so trying to combine them is a highly challenging task. Imagine you want to stack your two hands by matching each finger while both palms face the same direction. You will find out it is impossible to do it. You can only do this if you can trick your two hands into having the same chirality, says Hanbin Mao. This is what the research team has done; tricked the chirality. They have changed the peptide chirality from left to right, so it fits with the chirality of the DNA and works with it instead of repelling it.

This is the first study to show that the chirality of DNA and peptide structures can communicate and interact, when their handedness is changed, says Chenguang Lou. The researchers also report to be the first to provide an answer to why the biological world is chiral: The answer is energy: the chiral world requires the lowest energy to maintain, therefore it is most stable, says Hanbin Mao. In other words: Nature will always seek to spend as little energy as possible.

Source: https://www.sdu.dk/

Successful Transplant of Porcine Heart into Adult Human

In a first-of-its-kind surgery, a 57-year-old patient with terminal heart disease received a successful transplant of a genetically-modified pig heart and is still doing well three days later. It was the only currently available option for the patient. The historic surgery was conducted by University of Maryland School of Medicine (UMSOM) faculty at the University of Maryland Medical Center (UMMC), together known as the University of Maryland Medicine.

This organ transplant demonstrated for the first time that a genetically-modified animal heart can function like a human heart without immediate rejection by the body. The patient, David Bennett, a Maryland resident, is being carefully monitored over the next days and weeks to determine whether the transplant provides lifesaving benefits. He had been deemed ineligible for a conventional heart transplant at UMMC as well as at several other leading transplant centers that reviewed his medical records.

 “It was either die or do this transplant. I want to live. I know it’s a shot in the dark, but it’s my last choice,” said Mr. Bennett, the patient, a day before the surgery was conducted. He had been hospitalized and bedridden for the past few months.  I look forward to getting out of bed after I recover.

The U.S. Food and Drug Administration granted emergency authorization for the surgery on New Year’s Eve through its expanded access (compassionate use) provision. It is used when an experimental medical product, in this case the genetically-modified pig’s heart, is the only option available for a patient faced with a serious or life-threatening medical condition. The authorization to proceed was granted in the hope of saving the patient’s life.

“This was a breakthrough surgery and brings us one step closer to solving the organ shortage crisis. There are simply not enough donor human hearts available to meet the long list of potential recipients,” said Bartley P. Griffith, MD, who surgically transplanted the pig heart into the patient. Dr. Griffith is the Thomas E. and Alice Marie Hales Distinguished Professor in Transplant Surgery at UMSOM. “We are proceeding cautiously, but we are also optimistic that this first-in-the-world surgery will provide an important new option for patients in the future.”

Considered one of the world’s foremost experts on transplanting animal organs, known as xenotransplantation, Muhammad M. Mohiuddin, MD, Professor of Surgery at UMSOM, joined the UMSOM faculty five years ago and established the Cardiac Xenotransplantation Program with Dr. Griffith. Dr. Mohiuddin serves as the program’s Scientific/Program Director and Dr. Griffith as its Clinical Director.

“This is the culmination of years of highly complicated research to hone this technique in animals with survival times that have reached beyond nine months. The FDA used our data and data on the experimental pig to authorize the transplant in an end-stage heart disease patient who had no other treatment options,” said Dr. Mohiuddin.The successful procedure provided valuable information to help the medical community improve this potentially life-saving method in future patients.

Source: https://www.medschool.umaryland.edu/

The Most Powerful Quantum Computer Ever

A team of physicists from the Harvard-MIT Center for Ultracold Atoms and other universities has developed a special type of quantum computer known as a programmable quantum simulator capable of operating with 256 quantum bits, or “qubits.” The system marks a major step toward building large-scale quantum machines that could be used to shed light on a host of complex quantum processes and eventually help bring about real-world breakthroughs in material science, communication technologies, finance, and many other fields, overcoming research hurdles that are beyond the capabilities of even the fastest supercomputers today. Qubits are the fundamental building blocks on which quantum computers run and the source of their massive processing power.

This moves the field into a new domain where no one has ever been to thus far,” said Mikhail Lukin, the George Vasmer Leverett Professor of Physics, co-director of the Harvard Quantum Initiative, and one of the senior authors of the study published today in the journal Nature. “We are entering a completely new part of the quantum world.” 

According to Sepehr Ebadi, a physics student in the Graduate School of Arts and Sciences and the study’s lead author, it is the combination of system’s unprecedented size and programmability that puts it at the cutting edge of the race for a quantum computer, which harnesses the mysterious properties of matter at extremely small scales to greatly advance processing power. Under the right circumstances, the increase in qubits means the system can store and process exponentially more information than the classical bits on which standard computers run

The number of quantum states that are possible with only 256 qubits exceeds the number of atoms in the solar system,” Ebadi said, explaining the system’s vast size.

Already, the simulator has allowed researchers to observe several exotic quantum states of matter that had never before been realized experimentally, and to perform a quantum phase transition study so precise that it serves as the textbook example of how magnetism works at the quantum level.

Source: https://www.thebrighterside.news/

mRNA Technology Now Used Sucessfully to Treat Heart Disease

Combining technologies that proved hugely successful against cancer and in COVID-19 vaccines, researchers at the University of Pennsylvania have shown they can effectively treat a leading cause of heart disease. For now the success has only been achieved in mice, but the milestone offers hope for millions of people whose heart muscle is damaged by scar tissue. There is no effective treatment for this fibrosis, which leads to heart disease, the leading cause of death in the United States, said Dr. Jonathan Epstein, a Penn professor of cardiovascular research who helped lead the new work, published in the journal Science.

In his new research, Epstein reversed fibrosis by re-engineering cells, as has been done with a successful blood cancer treatment called CAR-T. In this case, however, the treatment took place inside the body rather than in a lab dish. The team delivered the treatment using mRNA technology, which has been proven over the last year with hundreds of millions of people receiving mRNA-based COVID vaccines.

If it works (in people), it really could have enormous impact,” Epstein said. “Almost every type of heart disease is accompanied by fibrosis.”

About 50% of heart failure is directly caused by this scar tissue, which prevents the heart from relaxing and pumping effectively. Fibrosis also is involved in leading causes of lung and kidney disease.

Source: https://eu.usatoday.com

China’s ‘Artificial Sun’ Just Broke a Major World Record For Plasma Fusion

Just seven months after it announced a milestone record for plasma fusion, the Chinese Academy of Sciences has absolutely smashed it. Their ‘artificial Sun tokomak reactor has maintained a roiling loop of plasma superheated to 120 million degrees Celsius (216 million degrees Fahrenheit) for a gobsmacking 1,056 seconds, the Institute of Plasma Physics reports. This also beats the previous record for plasma confinement of 390 seconds, set by the Tore Supra tokamak in France in 2003.

This breakthrough by the EAST (Experimental Advanced Superconducting Tokamak, or HT-7U) reactor is a significant advance for fusion experimentation in the pursuit of fusion energy. Succeeding in the generation of usable amounts of energy via nuclear fusion would change the world, but it’s incredibly challenging to accomplish. It involves replicating the processes that take place in the heart of a star, where high pressure and temperature squeeze atomic nuclei together so tightly that they fuse to form new elements. In the case of main sequence stars, these nuclei are hydrogen, which fuse to form helium. Since one helium nucleus is less massive than the four hydrogen nuclei that fuse to make it, the excess mass is radiated as heat and light. This generates a tremendous amount of energy – enough to power a star – and scientists are striving to harness the same process here on Earth. Obviously, there’s a significant challenge in creating the heat and pressure that we find in the heart of a star, and there are different technologies to address them.
In a tokamak, plasma is superheated, and confined in the shape of a torus, or donut, by powerful magnetic fields. But maintaining that confined, superheated plasma for longer time frames in order to cultivate longer reaction times is another problem, since superheated plasmas are chaotic and turbulent, prone to instabilities, resulting in leakage. EAST previously reported a temperature record of 160 million degrees Celsius (288 million degrees Fahrenheit), sustained for 20 seconds (the Sun’s core, for context, is 15 million degrees Celsius; the extra heat in a tokamak makes up for the lower pressure).
On 30 December 2021 – just squeaking in for its goal of achieving 1,000 seconds in 2021 – EAST broke the time record, too. Make no mistake, fusion still has a very long way to go. At the moment, far more energy goes into a fusion generator than we can get out of it; but lengthening the time of plasma confinement is a really important step forward in making self-sustaining plasma fusion a reality.

Source: https://www.sciencealert.com/

SuperGrids: How to Join the Solar Power Grids of Entire Continents

India gained notoriety when it finished November’s COP26 climate summit by weakening a move to end the use of coal. Less widely recognised is that the country also started the Glasgow summit in a more positive fashion, with a plan to massively expand the reach of solar power by joining up the electricity grids of countries and even entire continents. Indian prime minister Narendra Modi has talked about the idea before, but the One Sun One World One Grid initiative launched in Glasgow now has the backing of more than 80 countries, including Australia, the UK and the US. The alliance is just one example of a growing movement to create regional and, eventually, globalsupergrids”: long-distance, high-voltage cables linking each country’s growing renewable power output.

The supergrid movement is being driven partly by the need to maintain a smooth flow of power onto electricity grids. Local weather makes the amount of power generated by wind and solar variable, but this becomes less of an issue if the grid is larger and distributed over a wider geographical area. What’s more, supersized green energy projects are often sited far from the cities or industrial areas demanding their energy, be it wind farms in the North Sea or solar farms in the Australian outback. Supergrids offer a solution to this problem by connecting large renewable energy sources with the people who use the power.

The Indian government is keen on links to the Middle East, to help India decarbonise using imported renewable energy,” says Jim Watson at University College London. The UK, one of India’s partners on the One Sun One World One Grid initiative, is also considering new long-distance cables.

Last September, the UK started importing hydropower from Norway via a 724-kilometre subsea cable. In the coming years, the cable is expected to be used mostly to export electricity from the UK’s growing number of offshore wind farms so that it can be stored in hydropower facilities in Norway and released onto grids as needed. In 2022, UK start-up Xlinks will try to persuade the UK government to guarantee a minimum price for electricity generated at a mega wind and solar farm to be built in Morocco that could power UK homes via a 3800-kilometre subsea cable. “I will very confidently predict that over the next 15 years the world will see a huge number of interconnectors,” says Simon Morrish at Xlinks of such cables.

Xlinks is also working with Australian firm Sun Cable on its proposal to build the world’s largest solar farm in the north of Australia and connect it, via Darwin, to Singapore through a 4200-kilometre cable, to supply it with low-carbon electricity. In September, Sun Cable gained approval to route the high-voltage cable through Indonesian waters. 2022 may also see progress on efforts to build an “energy island” in the North Sea, which would act as a vast hub for offshore wind farms that can supply several European countries. UK company National Grid recently told New Scientist it is in talks about the pioneering project.

Source: https://www.newscientist.com/

Ultrathin, Lightweight Solar Panels

A race is on in solar engineering to create almost impossibly-thin, flexible solar panels. Engineers imagine them used in mobile applications, from self-powered wearable devices and sensors to lightweight aircraft and electric vehicles. Against that backdrop, researchers at Stanford University have achieved record efficiencies in a promising group of photovoltaic materials. Chief among the benefits of these transition metal dichalcogenides – or TMDs – is that they absorb ultrahigh levels of the sunlight that strikes their surface compared to other solar materials.

Transition metal dichalcogenide solar cells on a flexible polyimide substrate

Imagine an autonomous drone that powers itself with a solar array atop its wing that is 15 times thinner than a piece of paper,” said Koosha Nassiri Nazif, a doctoral scholar in electrical engineering at Stanford and co-lead author of a study published in the Dec. 9 edition of Nature Communications. “That is the promise of TMDs.”

The search for new materials is necessary because the reigning king of solar materials, silicon, is much too heavy, bulky and rigid for applications where flexibility, lightweight and high power are preeminent, such as wearable devices and sensors or aerospace and electric vehicles.

Silicon makes up 95 percent of the solar market today, but it’s far from perfect. We need new materials that are light, bendable and, frankly, more eco-friendly,” said Krishna Saraswat, a professor of electrical engineering and senior author of the paper. While TMDs hold great promise, research experiments to date have struggled to turn more than 2 percent of the sunlight they absorb into electricity. For silicon solar panels, that number is closing in on 30 percent. To be used widely, TMDs will have to close that gap.

The new Stanford prototype achieves 5.1 percent power conversion efficiency, but the authors project they could practically reach 27 percent efficiency upon optical and electrical optimizations. That figure would be on par with the best solar panels on the market today, silicon included.

Moreover, the prototype realized a 100-times greater power-to-weight ratio of any TMDs yet developed. That ratio is important for mobile applications, like drones, electric vehicles and the ability to charge expeditionary equipment on the move. When looking at the specific power – a measure of electrical power output per unit weight of the solar cell – the prototype produced 4.4 watts per gram, a figure competitive with other current-day thin-film solar cells, including other experimental prototypes. “We think we can increase this crucial ratio another ten times through optimization,” Saraswat said, adding that they estimate the practical limit of their TMD cells to be a remarkable 46 watts per gram.”

Source: https://news.stanford.edu/

Mind-controlled Robots

Two EPFL research groups teamed up to develop a machine-learning program that can be connected to a human brain and used to command a robot. The program adjusts the robot’s movements based on electrical signals from the brain. The hope is that with this invention, tetraplegic patients will be able to carry out more day-to-day activities on their own. Tetraplegic patients are prisoners of their own bodies, unable to speak or perform the slightest movement. Researchers have been working for years to develop systems that can help these patients carry out some tasks on their own.

People with a spinal cord injury often experience permanent neurological deficits and severe motor disabilities that prevent them from performing even the simplest tasks, such as grasping an object,” says Prof. Aude Billard, the head of EPFL’s Learning Algorithms and Systems Laboratory. “Assistance from robots could help these people recover some of their lost dexterity, since the robot can execute tasks in their place.”

Prof. Billard carried out a study with Prof. José del R. Millán, who at the time was the head of EPFL’s Brain-Machine Interface Laboratory but has since moved to the University of Texas. The two research groups have developed a computer program that can control a robot using electrical signals emitted by a patient’s brain. No voice control or touch function is needed; patients can move the robot simply with their thoughts. The study has been published in Communications Biology, an open-access journal from Nature Portfolio.

To develop their system, the researchers started with a robotic arm that had been developed several years ago. This arm can move back and forth from right to left, reposition objects in front of it and get around objects in its path. “In our study we programmed a robot to avoid obstacles, but we could have selected any other kind of task, like filling a glass of water or pushing or pulling an object,” says Prof. Billard. This entailed developing an algorithm that could adjust the robot’s movements based only on a patient’s thoughts. The algorithm was connected to a headcap equipped with electrodes for running electroencephalogram (EEG) scans of a patient’s brain activity. To use the system, all the patient needs to do is look at the robot. If the robot makes an incorrect move, the patient’s brain will emit an “error message” through a clearly identifiable signal, as if the patient is saying “No, not like that.” The robot will then understand that what it’s doing is wrong – but at first it won’t know exactly why. For instance, did it get too close to, or too far away from, the object? To help the robot find the right answer, the error message is fed into the algorithm, which uses an inverse reinforcement learning approach to work out what the patient wants and what actions the robot needs to take. This is done through a trial-and-error process whereby the robot tries out different movements to see which one is correct.

The process goes pretty quickly – only three to five attempts are usually needed for the robot to figure out the right response and execute the patient’s wishes. “The robot’s AI program can learn rapidly, but you have to tell it when it makes a mistake so that it can correct its behavior,” says Prof. Millán. “Developing the detection technology for error signals was one of the biggest technical challenges we faced.” Iason Batzianoulis, the study’s lead author, adds: “What was particularly difficult in our study was linking a patient’s brain activity to the robot’s control system – or in other words, ‘translating’ a patient’s brain signals into actions performed by the robot. We did that by using machine learning to link a given brain signal to a specific task. Then we associated the tasks with individual robot controls so that the robot does what the patient has in mind.

Source: https://actu.epfl.ch/