Harvard scientists report they have succeeded in creating the rarest material on the planet— atomic metallic hydrogen.
Thomas D. Cabot Professor of the Natural Sciences Isaac Silvera and postdoctoral fellow Ranga Dias, have begun to answer some fundamental questions about the nature of matter with the material, which is believed to have a number of applications, including as a room-temperature superconductor.
“This is the Holy Grail of high-pressure physics,” Silvera said in a statement. “It’s the first-ever sample of metallic hydrogen on Earth, so when you’re looking at it, you’re looking at something that’s never existed before.”
Silvera and Dias were able to squeeze a tiny hydrogen sample at 495 gigapascal (GPa) or more than 71.7 million pounds per square inch, which is greater than the pressure at the center of the Earth.
According to Silvera, at such extreme pressures solid molecular hydrogen, which consists of molecules on the lattice sites of the solid, breaks down and the tightly bound molecules dissociate to transform into atomic hydrogen.
In the experiment, the two researchers used two small pieces of carefully polished synthetic diamond and treated them to make them even tougher. They then mounted them opposite each other in a device called a diamond anvil cell.
“Diamonds are polished with diamond powder and that can gouge out carbon from the surface,” Silvera said. “When we looked at the diamond using atomic force microscopy, we found defects, which could cause it to weaken and break.”
They were able to use a reactive ion etching process to shave a tiny layer—just five microns thick—from the diamond’s surface and then coated the diamond with a thin layer of alumina to prevent the hydrogen from diffusing into the crystal structure and embrittling it.
Silvera said the discovery could lead to new materials.
“One prediction that’s very important is metallic hydrogen is predicted to be meta-stable,” Silvera said. “That means if you take the pressure off, it will stay metallic, similar to the way diamonds form from graphite under intense heat and pressure, but remain diamonds when that pressure and heat are removed.”
Silvera said understanding whether the material is stable could suggest that metallic hydrogen could act as a superconductor at room temperatures.
“As much as 15 percent of energy is lost to dissipation during transmission,” he said, “so if you could make wires from this material and use them in the electrical grid, it could change that story.”
Dias explained that a room temperature superconductor could change the transportation system by making magnetic levitation of high-speed trains possible, as well as making electric cars more efficient and improving the performance of many electronic devices.
Other applications for the material could provide major improvements in energy production and storage, because superconductors have zero resistance, making superconducting coils more useful to store excess energy, which could then be used whenever it is needed.
Another application could be as a more powerful rocket propellant.
“It takes a tremendous amount of energy to make metallic hydrogen,” Silvera said. “And if you convert it back to molecular hydrogen, all that energy is released, so that would make it the most powerful rocket propellant known to man, and could revolutionize rocketry.”
Fuels are often measured by a specific impulse—a measure in seconds of how fast a propellant is fired from the back of the rocket.
The most powerful fuels in use today have a specific impulse of about 450 seconds, while the specific impulse for metallic hydrogen is theorized to be 1,700 seconds.
“That would easily allow you to explore the outer planets,” Silvera said. “We would be able to put rockets into orbit with only one stage, versus two and could send up larger payloads, so it could be very important.”
The study was published in Science.
While the Harvard scientists believe they have made the breakthrough that researchers have been trying to discover for several decades, others aren’t so sure.
In a recent article published in Nature, five experts reported doubt on the discovery of metallic hydrogen, saying that the accompanying paper is not convincing.
By: R&D magazine, USA
Source: www.rdmag.comRead More
Deep learning-based system could be further developed for smartphones, increasing access to screening and aiding early detection of cancers
Computers can classify skin cancers as successfully as human experts, according to the latest research attempting to apply artificial intelligence to health.
The US-based researchers say the new system, which is based on image recognition, could be developed for smartphones, increasing access to screening and providing a low-cost way to check whether skin lesions are cause for concern.
“We hope that this is a first step towards early detection,” said Andre Esteva, an electrical engineering PhD student from Stanford University and co-author of the research.
According to the World Health Organisation, skin cancer accounts for one in every three cancers diagnosed worldwide, with global incidence on the rise.
In the UK alone, 131,772 cases of non-melanoma skin cancer were recorded in 2014. In the same year there were 15,419 new cases of the deadliest skin cancer, melanoma, making it the fifth most common cancer, according to Cancer Research UK.
As the disease is often initially spotted by a visual examination, Esteva teamed up with colleagues in fields ranging from dermatology to artificial intelligence to create a computer system that would aid screening.
Their approach, described in the journal Nature, is based on deep learning – a class of algorithms used for artificial intelligence. When fed with a large set of ready-sorted data these algorithms pick out and “learn” patterns and relationships. Once trained, the algorithms can then be used to categorise new, unsorted data.
To create the system, the team harnessed a deep learning algorithm built by Google that had already been presented with 1.28 million images of objects such as cats, dogs and cups. Esteva and colleagues then fed the system more than 127,000 clinical images of skin lesions, each already labelled, encompassing many different skin diseases.
Once trained, the team then tested the system’s ability to classify skin cancer by presenting it with just under 2,000 previously unseen images of skin lesions, whose nature had previously been determined by biopsy, and further compared the results for nearly 400 of the images against the judgement of at least 21 dermatologists.
The results reveal that the system is on a par with – if not better than – the experts in telling apart carcinomas from common benign skin growths and melanomas from moles.
For melanomas, the average dermatologist classified around 95% of malignant lesions and 76% of harmless moles correctly. By comparison, the algorithm is capable of correctly classifying 96% of malignant lesions, and correspondingly 90% of benign lesions.
“The aim is absolutely not to replace doctors nor to replace diagnosis,” said Esteva. “What we are replicating [is] sort of the first two initial screenings that a dermatologist might perform.”
While Esteva and colleagues admit the system needs further testing in clinical settings they believe the approach has great promise, suggesting it could be applied to a host of other medical fields.
Boguslaw Obara, a computer scientist at Durham University and expert in image processing, said that the size and complexity of the dataset used to train the system was impressive. The work, he adds, shows we are likely to see algorithms cropping up more and more in everyday life.
Dr Anjali Mahto, consultant dermatologist and spokesperson for the British Skin Foundation also welcomed the research. “This is an exciting new technology that has the potential to increase access to dermatology at a time where there is a national shortage in this speciality and the rates of skin cancer continue to rise,” she said.
But, Mahto warned, the system will need to be carefully assessed for its benefits before it can be rolled out. The approach is also unlikely to replace the role of dermatologists, she adds, pointing out that during a full-body examination experts often discover skin cancer at different sites to those that initially concerned the patient. “There is therefore a possibility that if you rely on people to self-report what they are worried about, other skin cancers – particularly in hard to see sites, e.g. the back – may be missed,” she said.
By: The Guardian, UK
Source: www.theguardian.comRead More
Food waste is a trillion dollar problem around the world but Denmark has managed to cut the amount of food it throws away by a quarter. Here’s how it did it.
On a chilly summer’s night in the centre of Copenhagen, a crowd gathers around the entrance of a restaurant called Dalle Valle. It’s 22:30 and the dinner buffet is winding up and the kitchens are about to close. But these people, mostly in their 20s and 30s, are here for the food that the diners inside didn’t want.
Dalle Valle is one of hundreds of restaurants and cafes listed in an app called Too Good To Go, which lets you order takeaway food that would otherwise be thrown away, for knock-down prices. It’s an example of many social initiatives set up in the last few years to address the growing problem of food waste. And in Denmark, they are leading the world.
Like many countries, Denmark has a problem with food waste. A 2014 government survey estimated that each household in the country throws away 105kg of food each year on average. Worth around 3,000 kroner (£350), that’s more than a month’s worth of food for most families. Shops will also discard food with minor cosmetic flaws. It is common for bakery staff to throw away rolls or loaves of bread that come out of the oven the wrong size or shape, for example.
Across Europe, 100m tonnes of food a year ends up in landfills. As the food decomposes, it produces an estimated 227 tonnes of CO2 equivalent gases – roughly as much as the total fossil-fuel emissions of Spain.
And it’s not just a problem in rich countries. The United Nation’s Food and Agriculture Organization estimates that roughly the same amount of food goes to waste in developing nations as industrialised ones: around 630 and 670m tonnes respectively. In all, a third of the food produced for human consumption each year – a trillion dollar’s worth – goes in the bin.
A third of the food produced each year – a trillion dollar’s worth – goes in the bin
Now Denmark is showing other countries what can be done. It has reduced its food waste by 25% in the last five years, according to a study by the Danish Agriculture and Food Council. Its success is largely down to changing shoppers’ habits. Last year two branches of a supermarket called WeFood opened in Copenhagen. The shops only sell food that has passed its sell-by date.
The UK comes in second. Between 2008 and 2013, it reduced its waste by 21%. And the Real Junk Food Project opened the UK’s first surplus-food store in Leeds in September.
Yet Denmark now has more initiatives tackling food waste than any other country in the world. And most of this activity can be traced back to Selina Juul, a Russian graphic designer turned food activist, who started a movement called Stop Spild Af Mad (“Stop Wasting Food”) eight years ago.
When Juul moved to Denmark in the 1990s to study, she was delighted to see an abundance of food. “I came from Moscow where communism had just collapsed and supermarket shelves were constantly empty,” she says. “Food was an often unmet necessity.” But working part-time in a supermarket bakery, she was also shocked to see bread being discarded every day simply because it did not look right.
In 2008 Juul started a Facebook page urging Danes to stop wasting food. The page became so popular that she found herself discussing the issue on national television less than two weeks later. Juul was then contacted by REMA 1000, Denmark’s major discount supermarket chain, which wanted her to help find ways to curb food waste in their stores.
Around 29,000 tonnes of bread and cakes are discarded every year in Denmark, mainly because it is sold in portions larger than people need, says John Rosenlowe, a marketing manager at REMA 1000. To address the problem, the company reduced the size of its own-brand bread by 40-50%, dropping the price accordingly. As well as giving people less food to throw away at home, Rosenlowe says that the change has reduced food waste by stores and suppliers, which now discard fewer items for being too small.
To cut down on wasted food, one Danish supermarket halved the size of its bread
More businesses followed. Retailers such as Lidl and Coop Danmark, a large supermarket conglomerate, joined REMA 1000 in a drive to cut food waste. Lidl stopped offering discounts that encouraged people to buy more than they needed. Unilever sponsored free doggy bags in restaurants across Denmark to encourage people to take home their leftovers. And restaurants started selling leftover food via apps like Too Good To Go. Businesses that adopt practices to cut down waste are certified by an organisation called ReFood.
Non-profits also signed up. Ida Merethe Jorgensen, chairman of Danske Handicaporganisationer, a charity based in Kolding, works with a group of volunteers to collect unsold food and distribute it to low-income families, for example.
In most countries, including Denmark, there are no laws against selling or distributing food past its expiration date. But sell-by and use-by dates have conditioned people to think all food becomes inedible as soon as those dates pass. That’s changing, however. “I have learned that it will be cheaper for me to buy foods that are close to their expiry date,” says Aslan Husnu, a researcher at Aarhus University who hunts for discounted items in supermarkets. “To stop the waste all I need to do is buy small portions, buy frequently, and not fill my basket with only perfectly shaped food.”
Others are now following Denmark’s lead. France and Italy recently introduced laws that make it easier for businesses – including farmers – to donate leftover food to charities, for example. And smartphone apps that direct hungry people to surplus food have been set up in several countries. “An increasing number of social enterprises are popping up all over Europe,” says Tania Burnham at Too Good To Go. “With the average mobile phone user checking their phone every six seconds, it’s never been easier to interact with their target market.”
But Denmark’s example may not be easy to replicate everywhere. “Denmark is a small, relatively homogenous, social-democratic country that is used to making some decisions based on the common good and constraining individual choice,” says food sociologist Krishnendu Ray at New York University. That kind of policy does not go down so well in places like the United States, he says.
Food waste is by far the lowest hanging fruit from an environmental perspective
For Madeline Holtzman, reducing the amount of food we throw away should be a no-brainer, however. “One of the biggest contributors to methane emissions, food waste is by far the lowest hanging fruit from an environmental perspective and arguably the least polarising or politicised environmental hazards,” she says.
A postgraduate student at New York University, Holtzman thinks it is partly a matter of raising awareness so that people can make their own choices. She is working to help launch Toast Ale in the US – a British craft beer made from surplus bread. This spring she also plans to spend a month dumpster diving – living off food she finds in bins outside shops and restaurants – with a colleague from Toast Ale, documenting the experience.
Back in Denmark, Juul thinks that public awareness has spiked – so much so that there is now a deficit of surplus produce. She says that WeFood is struggling to stock its shelves because businesses that contribute unsold food to the supermarket find they have less to give away. And apps like Too Good To Go have become so popular that restaurants are having to turn people away.
So the next time you see a crowd queuing outside a restaurant, they might not be there for the main menu – they’d rather have the food headed for the bin.
By: BBC Future, UK
Singapore: Australian authorities have just approved a new drugvenetoclax that is touted to have the power to “melt away” certain advanced forms of chronic lymphocytic leukaemia (CLL). Leukemia is the most common type of cancer in Australia, with 1300 people diagnosed each year.
The drug is recommended for patients with relapsed or refractory CLL with 17p deletion – a mutation that makes the disease relatively resistant to standard treatment options – as well as for patients with relapsed or refractory CLL for whom no other treatment options are available.
Venetoclax was discovered and developed with scientists from US pharmaceutical companies AbbVie and Genentech, as part of an international collaboration with the Walter and Eliza Hall Institute. The first clinical trials for venetoclax started in Melbourne at the Institute’s Victorian Comprehensive Cancer Centre partners The Royal Melbourne Hospital and Peter MacCallum Cancer Centre and were led by Australian haematologists.
Professor Doug Hilton AO, director, Walter and Eliza Hall Institute of Medical Research expressed excitement on the news of the drug’s approval. He said that the drug will be most importantly benefit patients with limited treatment options.
“The fact that Australians with hard-to-treat chronic lymphocytic leukaemia can now benefit from a drug like venetoclax demonstrates how critically important medical research is to the health of our community,” Professor Hilton said.
“TGA approval of venetoclax is a major milestone in a journey spanning decades of powerful and innovative research by teams of leading scientists, clinicians and entrepreneurs, including more than one hundred researchers at Melbourne’s Walter and Eliza Hall Institute of Medical Research.”
Professor Andrew Roberts, a clinical haematologist at The Royal Melbourne Hospital and cancer researcher at the Walter and Eliza Hall Institute and the University of Melbourne, said venetoclax was being combined now with other approved drugs and undergoing phase 2 and phase 3 clinical trials in other blood cancers.
“The hope is that venetoclax, potentially in combination with other approved drugs, could benefit more patients including those with other hard-to-treat types of blood cancer,” Professor Roberts said. “Ongoing research suggests that this drug will be very active against other cancers, so this milestone may just be the beginning.”
By: BioSpectrum, Asia
Source: www.biospectrumasia.comRead More
A prototype device to detect the scent of disease
ONE of a doctor’s most valuable tools is his nose. Since ancient times, medics have relied on their sense of smell to help them work out what is wrong with their patients. Fruity odours on the breath, for example, let them monitor the condition of diabetics. Foul ones assist the diagnosis of respiratory-tract infections.
But doctors can, as it were, smell only what they can smell—and many compounds characteristic of disease are odourless. To deal with this limitation Hossam Haick, a chemical engineer at the Technion Israel Institute of Technology, in Haifa, has developed a device which, he claims, can do work that the human nose cannot.
The idea behind Dr Haick’s invention is not new. Many diagnostic “breathalysers” already exist, and sniffer dogs, too, can be trained to detect illnesses such as cancer. Most of these approaches, though, are disease-specific. Dr Haick wanted to generalise the process.
As he describes in ACS Nano, he and his colleagues created an array of electrodes made of carbon nanotubes (hollow, cylindrical sheets of carbon atoms) and tiny particles of gold. Each of these had one of 20 organic films laid over it. Each film was sensitive to one of a score of compounds known to be found on the breath of patients suffering from a range of 17 illnesses, including Parkinson’s disease, multiple sclerosis, bladder cancer, pulmonary hypertension and Crohn’s disease. When a film reacted, its electrical resistance changed in a predictable manner. The combined changes generated an electrical fingerprint that, the researchers hoped, would be diagnostic of the disease a patient was suffering from.
To test their invention, Dr Haick and his colleagues collected 2,808 breath samples from 1,404 patients who were suffering from at least one of the diseases they were looking at. Its success varied. It could distinguish between samples from patients suffering from gastric cancer and bladder cancer only 64% of the time. At distinguishing lung cancer from head and neck cancer it was, though, 100% successful. Overall, it got things right 86% of the time. Not perfect, then, but a useful aid to a doctor planning to conduct further investigations. And this is only a prototype. Tweaked, its success rate would be expected to improve.Read More
Plans for voting via ATM machines to massively boost turnout
Portugal has announced the world’s first participatory budget on a national scale. The project will let people submit ideas for what the government should spend its money on, and then vote on which ideas are adopted.
Although participatory budgeting has become increasingly popular around the world in the past few years, it has so far been confined to cities and regions, and no country that we know of has attempted it nationwide. To reach as many people as possible, Portugal is also examining another innovation: letting people cast their votes via ATM machines.
‘It’s about quality of life, it’s about the quality of public space, it’s about the quality of life for your children, it’s about your life, OK?’ Graça Fonseca, the minister responsible, told Apolitical. ‘And you have a huge deficit of trust between people and the institutions of democracy. That’s the point we’re starting from and, if you look around, Portugal is not an exception in that among Western societies. We need to build that trust and, in my opinion, it’s urgent. If you don’t do anything, in ten, twenty years you’ll have serious problems.’
Although the official window for proposals begins in January, some have already been submitted to the project’s website. One suggests equipping kindergartens with technology to teach children about robotics. Using the open-source platform Arduino, the plan is to let children play with the tech and so foster scientific understanding from the earliest age.
Proposals can be made in the areas of science, culture, agriculture and lifelong learning, and there will be more than forty events in the new year for people to present and discuss their ideas.
The organisers hope that it will go some way to restoring closer contact between government and its citizens. Previous projects have shown that people who don’t vote in general elections often do cast their ballot on the specific proposals that participatory budgeting entails. Moreover, those who make the proposals often become passionate about them, campaigning for votes, flyering, making YouTube videos, going door-to-door and so fuelling a public discussion that involves ever more people in the process.
On the other side, it can bring public servants nearer to their fellow citizens by sharpening their understanding of what people want and what their priorities are. It can also raise the quality of public services by directing them more precisely to where they’re needed as well as by tapping the collective intelligence and imagination of thousands of participants.
The model began in Porto Alegre, Brazil, in 1989, and has become popular around the world in recent years, with more than 1,500 places estimated to have adopted some variation. The largest by funding is in Paris. In 2016, only its third year, the scheme disbursed €100million (some $110million) and it plans to have spent €500million ($550million) by 2020.
Although Portugal has allocated only €3million for this first year, the fact that it is operating nationwide has given rise to some special characteristics. For one thing, Portugal has ten million inhabitants, compared with some two and a quarter million Parisians, of whom 158,000 voted. For another, while one pot of money has been allocated to specific regional projects, the proposals drawing on the national pot must improve the links between different parts of the country by working across them.
‘Portugal is well-established in terms of its territory, borders, population, and has a cohesive identity,’ said Fonseca. ‘But we need to be able to better connect the interior and the littoral, urban and rural areas, and we have a chance to do it because we are a medium-sized country that is very coherent.’
Nevertheless, it is difficult to reach people in the poorest and most rural areas, and one of the perennial problems with participatory budgeting is that people who are already marginalised often fail to assert their agenda. This is where the ATM idea comes in.
Although it will not be used this year, because the project is still very much in the trial phase, the use of ATMs is potentially revolutionary. As Fonseca puts it, ‘In every remote part of the country, you might have nothing else, but you have an ATM.’ Moreover, an ATM could display proposals and allow people to vote directly, not least because it already contains a secure way of verifying their identity. At the moment, for comparison, people can vote by text or online, sending in the number from their ID card, which is checked against a database.
For now, Fonseca and her colleagues are concentrating on making this trial run smoothly. Before taking this job, she ran Lisbon’s participatory budget for six years, developing it in discussion with colleagues from Paris, New York and Brazil, and she believes that it will take at least five years for the nationwide program to become known and recognised.
‘I’ve been in this process for so many years now and I always have the same feeling,’ she said. ‘In these times of so much information, you’re so surrounded by content and social networks that it’s difficult to get to people and say: this is happening. We’ll probably get a lot of people voting if we have a good lot of proposals. If people see proposals that they relate to, that they see will be good for their regions, for their cities, for their neighbourhoods, then people will campaign and they will vote.’
By: apolitical, UK
Source: apolitical.coRead More