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Einstein’s death 60 years ago was just the start of a strange journey for the most prized part of his anatomy, his brain. Stored in jars and on slides, it is still inspiring awe and scholarly research.
At 01:15 in the morning of 18 April 1955, Albert Einstein – theoretical physicist, peace campaigner and undisputed genius – mumbled a few words in German, took two breaths, and died. The nurse on duty at Princeton Hospital did not speak German and the meaning of Einstein’s final words was lost forever. Einstein’s cremation took place later that day in Trenton, New Jersey, but the following day his son, Hans Albert, learned that the body in the coffin had not been intact. A front-page article in the New York Times reported that “the brain that worked out the theory of relativity and made possible the development of nuclear fission” had been removed “for scientific study”.
The pathologist who conducted the autopsy, Dr Thomas Harvey, had gone further than simply identifying the cause of death – a burst aorta. He had sawed open Einstein’s cranium and removed its celebrated contents.
“He had some big professional hopes pinned on that brain,” says Carolyn Abraham, who met Harvey while researching her book Possessing Genius: The Bizarre Odyssey of Einstein’s Brain. “I think he had hoped to make a name for himself in medicine in a way that he had been unable to do. And then he comes to work one morning and finds Albert Einstein on his autopsy table.”
Hans Albert was furious. His father had been a modest man who had been cremated without ceremony, and had asked for his ashes be scattered in secret to prevent the site becoming a place of pilgrimage.
But Einstein had also, at some point, given people to believe he was happy for scientists to use his body for research. Harvey convinced Hans Albert to grant permission for a study of Einstein’s brain in the hope it would, as the New York Times put it later, “shed light on one of nature’s greatest mysteries – the secret of genius”.
Harvey, controversially, took possession of the brain. “Whether he took it for himself, or took it for science – it was hard for people to know which, and that’s what put him in the crosshairs for a lot of people,” says the journalist Michael Paterniti, who met Harvey near the end of his life. Harvey was not a neurologist, but he promised to marshal the country’s greatest specialists to study the brain, and to publish their findings soon. Moe here The strange afterlife of Einstein’s brain
Researchers in the US have taken a big step towards creating a computer that works like a human brain. That might sound creepy, but the brain is already the most efficient computer that we know of – it’s super-fast, has nearly limitless memory, doesn’t need to ‘boot up’, and requires hardly any energy to run. If we could find a way to make a computer that works in the same way, it would revolutionise technology. One of the keys to making these devices is improving something called the memory resistor, or ‘memristor’, which remembers how much current has flown through it. This means that, unlike the flash and RAM memory we currently rely on, it will be much faster, and able to recall data even if the system loses power.
“Memristors could be used as a memory element in an integrated circuit or computer,” said one of the team, computer engineer Mark Hersam from Northwestern University in the US, in a press release. “Unlike other memories that exist today in modern electronics, memristors are stable and remember their state even if you lose power.”
Memristors were first proposed back in 1971, but there’s been one big thing holding them back so far – we’ve only managed to create two-terminal devices that can control just one voltage channel, and are incompatible with our current computing technology. But now Hersam and his team have managed to add another electrode and transform the memristor into a three-terminal device, allowing it to be used in more complex electronic circuits and systems.
“With a memristor that can be tuned with a third electrode, we have the possibility to realise a function you could not previously achieve,” Hersam said. “A three-terminal memristor has been proposed as a means of realising brain-like computing. We are now actively exploring this possibility in the laboratory.” Via We may soon have the building blocks for brain-like computers
The UK death rate has reached a tipping point with numbers of deaths expected soon to begin rising after falling for decades, suggests a report. The oldest of the post war baby-boom generation, born in 1945, will turn 70 this year says the International Longevity Centre (ILC-UK). The number of deaths is likely to rise 20% over the next 20 years, suggests an analysis of official figures. The increase is likely to push up funeral prices, say the authors.
Since the 1990s the number of deaths in the UK has seen a downward trend, but this is about to reverse, says the report, The Funeral Time bomb, to be published on Monday. Almost 16m children were born in the 20 years after World War Two, peaking at 881,026 in 1947, say the authors.
“As a result of their ageing, the proportion of our population aged over 65 is projected to rise from around 18% today to over 22%. “The greying of the baby boomers also means that an increasing number and proportion of the UK population are nearing the end of their lives. “The resulting inevitable increase in the number of deaths coincides with the significant increases in funeral costs which are already at an all-time high.”
With life expectancy for men in this group of 86 and for women of 89, annual deaths in the UK are expected to reach 627,000 by 2037, compared with 521,000 this year, says the report. Via Warning of ‘funeral time bomb’ in UK as population ages
About 4 billion years ago, molecules began to make copies of themselves, an event that marked the beginning of life on Earth. A few hundred million years later, primitive organisms began to split into the different branches that make up the tree of life. In between those two seminal events, some of the greatest innovations in existence emerged: the cell, the genetic code and an energy system to fuel it all. All three of these are essential to life as we know it, yet scientists know disappointingly little about how any of these remarkable biological innovations came about.
“It’s very hard to infer even the relative ordering of evolutionary events before the last common ancestor,” said Greg Fournier, a geobiologist at the Massachusetts Institute of Technology. Cells may have appeared before energy metabolism, or perhaps it was the other way around. Without fossils or DNA preserved from organisms living during this period, scientists have had little data to work from.
Fournier is leading an attempt to reconstruct the history of life in those evolutionary dark ages — the hundreds of millions of years between the time when life first emerged and when it split into what would become the endless tangle of existence.
He is using genomic data from living organisms to infer the DNA sequence of ancient genes as part of a growing field known as paleogenomics. In research published online in March in the Journal of Molecular Evolution, Fournier showed that the last chemical letter added to the code was a molecule called tryptophan — an amino acid most famous for its presence in turkey dinners. The work supports the idea that the genetic code evolved gradually. Using similar methods, he hopes to decipher the temporal order of more of the code — determining when each letter was added to the genetic alphabet — and to date key events in the origins of life, such as the emergence of cells. Via Paleogenomics Reconstructs Ancient Proteins
More American homes could be powered by the earth’s natural underground heat with a new, nontoxic and potentially recyclable liquid that is expected to use half as much water as other fluids used to tap into otherwise unreachable geothermal hot spots. The fluid might be a boon to a new approach to geothermal power called enhanced geothermal systems. These systems pump fluids underground, a step that’s called “reservoir stimulation,” to enable power production where conventional geothermal doesn’t work.
The new reservoir stimulation fluid features an environmentally friendly polymer that greatly expands the fluid’s volume, which creates tiny cracks in deep underground rocks to improve power production. This fluid could also substantially reduce the water footprint and cost of enhanced geothermal systems. A paper describing the fluid has been published by the Royal Society of Chemistry in an advance online version of the journal Green Chemistry.
“Our new fluid can make enhanced geothermal power production more viable,” said lead fluid developer Carlos Fernandez, a chemist at the Department of Energy’s Pacific Northwest National Laboratory. “And, though we initially designed the fluid for geothermal energy, it could also make unconventional oil and gas recovery more environmentally friendly.” Via Packing heat: New fluid makes untapped geothermal energy cleaner.
Members of a troop of chimpanzees living at a site called Fongoli in southeastern Senegal have been observed by scientists fashioning tree branches into spears and using them to hunt and kill bushbabies. The researchers, a combined team with members from the U.S. the U.K. and Germany have published their observations and findings in Royal Society Open Science.
In their seven year study of the chimps living at the site, the researchers spotted chimpanzees breaking off tree branches, tearing off smaller branches and leaves, removing the weak tips and sometimes gnawing on the ends to sharpen them. The spears (which were on average about 75 centimeters long) were then used to stab bushbabies sleeping in their nests in tree hollows. The poking, the team reports was not lethal, instead, it caused injuries to the bushbabies which was enough to allow the chimps to bite and kill them with relative ease.
Bushbabies are small primates with big eyes and sharp teeth, and serve as a primary protein source for the chimps living in that part of Africa, where other sources are rare. The researchers began their study in 2007, observing chimp behavior up until last year. During that time period they recorded 308 spear hunting events, which they noted, was more common for females than males—they accounted for 61 percent of the total. The researchers suggest this is likely the case because it is more difficult for females to chase down prey because they almost always have offspring clinging to their bodies. To date, the chimps are the only known animal to use a tool as a weapon to hunt a “large” animal, other than humans—chimps in other troops have been seen to use twigs as tools to help collect termites, but scientists do not count that as hunting. Via Chimps in Senegal found to fashion spears for hunting.
A research team led by Shree K. Nayar, T.C. Chang Professor of Computer Science at Columbia Engineering, has invented a prototype video camera that is the first to be fully self-powered—it can produce an image each second, indefinitely, of a well-lit indoor scene. They designed a pixel that can not only measure incident light but also convert the incident light into electric power. The team is presenting its work at the International Conference on Computational Photography at Rice University in Houston, April 24 to 26.
“We are in the middle of a digital imaging revolution,” says Nayar, who directs the Computer Vision Laboratory at Columbia Engineering. He notes that in the last year alone, approximately two billion cameras of various types were sold worldwide. “I think we have just seen the tip of the iceberg. Digital imaging is expected to enable many emerging fields including wearable devices, sensor networks, smart environments, personalized medicine, and the Internet of Things. A camera that can function as an untethered device forever—without any external power supply—would be incredibly useful.”
A leading researcher in computational imaging, Nayar realized that although digital cameras and solar panels have different purposes – one measures light while the other converts light to power – both are constructed from essentially the same components. At the heart of any digital camera is an image sensor, a chip with millions of pixels. The key enabling device in a pixel is the photodiode, which produces an electric current when exposed to light. This mechanism enables each pixel to measure the intensity of light falling on it. The same photodiode is also used in solar panels to convert incident light to electric power. The photodiode in a camera pixel is used in the photoconductive mode, while in a solar cell it is used in the photovoltaic model. Via Engineering team invents a camera that powers itself.
A few days ago, Singaporean television host Kenneth Kong posted the below maths question on his Facebook page, and it went viral. The high school maths question was aimed at 15- to 17-year-olds, but somehow it managed to stump half the Internet. It even appeared on the New York Times science page, and prompted a blog from British author and numbers expert Alex Bellos over at The Guardian.
So when exactly is Cheryl’s birthday, and why is the problem so frustrating for so many adults? Before we get to the solution, let’s clear up any ambiguity with the wording, which Kenneth Chang over at The New York Times calls “terrible”.
To start with, Cheryl (who we can only imagine has set her birthday to private on Facebook) will only give Albert and Bernard 10 possible dates for her birthday.
May 15, May 16, May 19
June 17, June 18
July 14, July 16
August 14, August 15, August 17
She then whispers only the month of her birthday to Albert, and nothing but the date itself to Bernard. The information Albert receives convinces him that Bernard can’t possibly know the answer.
But knowing that is enough for Bernard to figure it out. In turn, Bernard’s certainty convinces Albert of the answer, too.
After searching 100,000 galaxies for signs of highly advanced extraterrestrial life, a team of scientists using observations from NASA’s WISE orbiting observatory has found no evidence of advanced civilizations in them. “The idea behind our research is that, if an entire galaxy had been colonized by an advanced spacefaring civilization, the energy produced by that civilization’s technologies would be detectable in mid-infrared wavelengths—exactly the radiation that the WISE satellite was designed to detect for other astronomical purposes,” said Jason T. Wright, an assistant professor of astronomy and astrophysics at the Center for Exoplanets and Habitable Worlds at Penn State University, who conceived of and initiated the research.
The research team’s first paper about its Glimpsing Heat from Alien Technologies Survey (G-HAT), will be published in the Astrophysical Journal Supplement Series on April 15, 2015. Also among the team’s discoveries are some mysterious new phenomena in our own Milky Way galaxy.
“Whether an advanced spacefaring civilization uses the large amounts of energy from its galaxy’s stars to power computers, space flight, communication, or something we can’t yet imagine, fundamental thermodynamics tells us that this energy must be radiated away as heat in the mid-infrared wavelengths,” Wright said. “This same basic physics causes your computer to radiate heat while it is turned on.”
Theoretical physicist Freeman Dyson proposed in the 1960s that advanced alien civilizations beyond Earth could be detected by the telltale evidence of their mid-infrared emissions. It was not until space-based telescopes like the WISE satellite that it became possible to make sensitive measurements of this radiation emitted by objects in space.
Roger Griffith, a postbaccalaureate researcher at Penn State and the lead author of the paper, scoured almost the entire catalog of the WISE satellite’s detections—nearly 100 million entries—for objects consistent with galaxies emitting too much mid-infrared radiation. He then individually examined and categorized around 100,000 of the most promising galaxy images. Wright reports, “We found about 50 galaxies that have unusually high levels of mid-infrared radiation. Our follow-up studies of those galaxies may reveal if the origin of their radiation results from natural astronomical processes, or if it could indicate the presence of a highly advanced civilization.”
In any case, Wright said, the team’s non-detection of any obvious alien-filled galaxies is an interesting and new scientific result. “Our results mean that, out of the 100,000 galaxies that WISE could see in sufficient detail, none of them is widely populated by an alien civilization using most of the starlight in its galaxy for its own purposes. That’s interesting because these galaxies are billions of years old, which should have been plenty of time for them to have been filled with alien civilizations, if they exist. Either they don’t exist, or they don’t yet use enough energy for us to recognize them,” Wright said. Via Search for advanced civilizations beyond Earth finds nothing obvious in 100,000 galaxies.
Thanks to recently identified specimens at the Yale Peabody Museum of Natural History, paleontologists now believe that mighty mosasaurs — which could grow to 50 feet long — gave birth to their young in the open ocean, not on or near shore. The findings answer long-held questions about the initial environment of an iconic predator that lived during the time of the dinosaurs. Mosasaurs populated most waters of the Earth before their extinction 65 million years ago.
“Mosasaurs are among the best-studied groups of Mesozoic vertebrate animals, but evidence regarding how they were born and what baby mosasaur ecology was like has historically been elusive,” said Daniel Field, lead author of a study published online April 10 in the journal Palaeontology. Field is a doctoral candidate in the lab of Jacques Gauthier in Yale’s Department of Geology and Geophysics.
In their study, Field and his colleagues describe the youngest mosasaur specimens ever found. Field had come across the fossils in the Yale Peabody Museum’s extensive collections. “These specimens were collected over 100 years ago,” Field said. “They had previously been thought to belong to ancient marine birds.” Field and Aaron LeBlanc, a doctoral candidate at the University of Toronto at Mississauga, concluded that the specimens showed a variety of jaw and teeth features that are only found in mosasaurs. Also, the fossils were found in deposits in the open ocean.
“Really, the only bird-like feature of the specimens is their small size,” LeBlanc said. “Contrary to classic theories, these findings suggest that mosasaurs did not lay eggs on beaches and that newborn mosasaurs likely did not live in sheltered nearshore nurseries.” ia Giant sea lizards in the age of dinosaurs: A new beginning for baby mosasaurs.
There’s real pressure on the aviation industry to introduce faster, cheaper and greener aircraft, while maintaining the high safety standards demanded of airlines worldwide.
Airlines carry more than three billion passengers each year, which presents an enormous challenge not only for aircraft manufacturers but for the civil aviation infrastructure that makes this extraordinary annual mass-migration possible. Many international airports are close to or already at capacity. The International Air Transport Association (IATA) has estimated that, without intervention, many global airports – including major hubs such as London Heathrow, Amsterdam Schiphol, Beijing and Dubai – will have run out of runway or terminal capacity by 2020.
The obvious approach to tackling this problem is to extend and enlarge airport runways and terminals – such as the long-proposed third runway at London Heathrow. However there may be other less conventional alternatives, such as introducing in-flight refuelling for civil aircraft on key long-haul routes. Our project, Research on a Cruiser-Enabled Air Transport Environment (Recreate), began in 2011 to evaluate whether this was something that could prove a viable, and far cheaper, solution.
If in-flight refuelling seems implausible, it’s worth remembering that it was first trialed in the 1920s, and the military has continued to develop the technology ever since. The appeal is partly to reduce the aircraft’s weight on take-off, allowing it to carry additional payload, and partly to extend its flight range. Notably, during the Falklands War in 1982 RAF Vulcan bombers used in-flight refuelling to stage what was at the time the longest bombing mission ever, flying 8,000 miles non-stop from Ascension Island in the South Atlantic to the Falklands and back.
The world’s first in-flight refuelling in 1923. Credit: AF.mil
Reducing take-off weight could offer many benefits for civilian aircraft too. Without the need to carry so much fuel the aircraft can be smaller, which means less noise on take-off and landing and shorter runways. This opens up the network of smaller regional airports as new potential sites for long-haul routes, relieving pressure on the major hubs that are straining at the seams.
There are environmental benefits too, as a smaller, lighter aircraft requires less fuel to reach its destination. Our initial estimates from air traffic simulations demonstrate that it’s possible to reduce fuel burn by up to 11% over today’s technology by simply replacing existing global long-haul flight routes with specifically designed 250-seater aircraft with a range of 6,000nm after one refuelling – roughly the distance from London to Hong Kong. This saving could potentially grow to 23% with further efficiencies, all while carrying the same number of passengers the same distance as is possible with the current aircraft fleet, and despite the additional fuel burn of the tanker aircraft. More here In-flight refuelling for airliners will see non-stop services shrink the globe.
Near-death experiences, in which people claim to encounter a variety of unusual phenomena, including moving through a tunnel toward light, feeling lightweight, feeling peace and joy, and profoundly spiritual moments, have often been classified by scientific researchers as a function of anoxia, or oxygen deprivation in the brain.
For many people, and the religious in particular, the phenomenon of near-death experience — assuming it’s real and not simply a result of a dying brain’s hallucinatory interpretation of a flood of brain chemicals — validates their belief in the afterlife and heaven. Many books have been written by people who claim to have come back from the brink of death and seen God and heaven (though earlier this year the best-selling memoir “The Boy Who Came Back From Heaven” was admitted by its author to have been faked).
Scientific evidence, however, suggests that the experience is not a spiritual or metaphysical one, but instead a chemical one. A new study in which researchers induced anoxia in rats offers more support for near-death experiences (NDEs) as happening inside the dying brain and being interpreted as an out-of-body or spiritual experience.
The researchers examined neurotransmitters, changes in brain and heart electrical activity and brain-heart connectivity. They concluded, “Asphyxia stimulates a robust and sustained increase of functional and effective cortical connectivity, an immediate increase in cortical release of a large set of neurotransmitters… . These results demonstrate that asphyxia activates a brainstorm, which accelerates premature death of the heart and the brain.”
According to an article at MedicalDaily.com, the researchers found that “the brain is much more active during the dying process than in the waking state… In the 30-second period after the animal’s hearts stopped beating, the researchers observed an immediate release of more than a dozen neurochemicals, while high-frequency brainwaves called gamma oscillations increased.
“This activity seemed to trigger a connection between the brain and the heart… . [Lead author Jimo] Borjigin believes a similar, elevated level of brain activity may also happen during the human experience of ‘near death’ and it is this that gives rise to a heightened state of consciousness, including the visions experienced by survivors of cardiac arrest.”
This “brainstorm,” or cascade of neurotransmitter chemicals, can cause benign hallucinations such as those reported in NDEs. This new study joins several others implicating anoxia as a contributing (if not causative) factor to near-death experiences. Researcher Borjigin had conducted previous research with similar findings in 2013, published in the Proceedings of the National Academy of Sciences. Via Near-Death Experiences Likely Caused by Lack of Oxygen
Researchers have found that male relatives of convicted sex offenders are five times more likely to commit a similar crime themselves, and that the risk is influenced heavily by their genes. The study, led by Niklas Långström, a professor of psychiatric epidemiology at the Karolinska Institute in Sweden, looked at 21,566 records from men who had been convicted of a sexual offence in Sweden between 1973 and 2009. The team chose to focus only on men, since less than 1 percent of convicted sexual offenders during this time were female.
The analysis revealed that 2.5 percent of men who were closely related to a sex offender – so, brothers or sons – ended up being convicted of a similar crime themselves, which is significantly higher than the 0.5 percent of men in the general population who are at some point convicted of a sexual offence.
“Having a father or a brother convicted of a sexual offence increased the odds of being convicted oneself four to five times compared with age-matched control men without a sexually aggressive father or brother,” the team writes in the International Journal of Epidemiology. This familial connection when it comes to sex offenders suggested to the researchers that something, either environmental or genetic, or both, was at play. Continue reading
Photosynthesis has two main stages: light reactions and dark reactions. The light processes the light from the sun, the dark is the internal process creating energy. It is also called the light reaction because direct sunlight is needed for solar energy to start the process. In the light reaction, chlorophyll absorbs the light and starts the chemical process that ends in creating oxygen. It is during this time that manganese is used in the reaction creating oxygen from water molecules.
Manganese basically uses its electrons to split the water. In what scientists call Photosystem II, this particular set up is the only time this biological enzyme is used to oxidize water. First manganese neutralizes the charge of the photon sent to it. This is the catalyst that then binds two water molecules together. From there it oxidizes molecules with an exchange of electrons. It is attributed to the fact that manganese can be found in multiple oxidation states, thus being able to hold electrons at different levels. This process is so complex that scientists have not been able to make a similar catalyst and be successful.
The dark reactions are done inside of the plant, and while often done during the day, it does not need direct light. During this reaction, the carbon dioxide is changed to sugar, which breaks down to glucose and fructose, and that is what the plant uses for energy. It is during the light reaction that manganese plays its most important role. The process of creating oxygen cannot be done without it, and we cannot live without oxygen. If photosynthesis did not use the water-to-oxygen process, the earth’s atmosphere would have a lot less oxygen for humans and animals.
It is in the basic process of collecting sunlight, and processing it for energy, that plants create life for us. As with most ecosystems, if one aspect changes, it can throw off the entire system. It’s the same at the cellular level as well: without manganese to oxidize the water, the world would be a different place. Edited from Manganese and Photosynthesis.
Recurring slope lineae (RSL) are active flows on warm Martian slopes that might be caused by seeping water. One of the most active sites known on Mars is in the central peaks (uplifted mountains of deep bedrock) of Hale Crater.
This image shows RSL extending downhill from bedrock cliffs, mostly towards the northwest (upper left). This image was acquired in middle summer when RSL are most active in the southern mid latitudes.
The RSL in Hale have an unusually “reddish” color compared to most RSL, perhaps due to oxidized iron compounds, like rust. Since HiRISE color is shifted to infra-red wavelengths, they are actually especially bright the near-infrared just beyond the range of human vision. Via NASA image
Measurements of an artificial radioactive element called lawrencium could revive an arcane controversy over the element’s position in the periodic table — and the structure of the table itself.
An international team of physicists and chemists reports in Nature1 that it takes very little energy to strip an electron out of an atom of lawrencium, element 103. The measurement is a tour de force of chemistry, because the radioactive element does not exist in nature, can be synthesized only in vanishingly small amounts, and lasts for mere seconds.
Lawrencium, named after physicist Ernest Lawrence, the inventor of the cyclotron particle accelerator, is the heaviest element for which researchers have yet measured the fundamental property known as the first ionization energy — the energy required to turn the atom into an ion by ripping out its most easily accessible electron. That measurement underpins researchers’ understanding of an atom’s chemistry, but until now had been known only for the elements up to einsteinium (atomic number 99). More here Nature News.
Researchers at Stanford University have demonstrated a fast and reliable method of extending the length of telomeres – the protective caps at the end of chromosomes that play a key role in aging.
As illustrated above, telomeres are regions of DNA at the ends of chromosomes. Like the plastic tips at the end of shoelaces, they protect chromosomes from unravelling and deteriorating, or mixing with other chromosomes. Over time, however, telomeres will begin to erode and shorten. When telomeres become critically short, the cell enters an inactive state, stops dividing and dies. More and more cells reacting in this way causes tissue degeneration, which gradually results in aging and disease. A young human starts with telomeres around 8,000-10,000 nucleotides long, with each cell division reducing this length, so a person in their 80s will average 4,000-6,000 nucleotides.
Researchers at Stanford University School of Medicine, in a study published this week by the FASEB Journal, have found a way to extend the length of human telomeres by up to 900 nucleotides – equivalent to over 10 years of additional lifespan. This was achieved with human muscle and skin cells in a Petri dish using modified messenger RNA (mRNA) containing TERT, a vital part of the telomerase complex. Telomerase is an enzyme that occurs naturally and is known to prevent the shortening of telomeres. It is common in stem cells, but most other cell types have very low levels. Continue reading