From Science Alert: “Scientists have performed the first trials of a ‘universal cancer vaccine’ “

Science Alert

2 JUN 2016
FIONA MACDONALD

Cancer Research UK via Henry Scowcroft/YouTube

It’s really happening.

Scientists just took a big, “very positive” step towards developing what could be the first ‘universal cancer vaccine’.

The results from early trials in humans, along with research in mice, have just been published, and they suggest that the new technique could be used to activate patients’ immune systems against any type of tumour, no matter where it is in the body.

Unlike the vaccines we’re familiar with, this potential vaccine would be given to patients who already have cancer, rather than those at risk of getting it. It basically works by shooting tiny ‘darts’ containing pieces of RNA extracted from the patient’s cancer cells at the body’s own immune system, convincing them to launch an all-out attack on any tumours they come across.

By just changing the RNA inside those darts, the team can, in theory, mobilise the immune system against any kind of cancer. “[Such] vaccines are fast and inexpensive to produce, and virtually any tumour antigen can be encoded by RNA,” the team, led by researchers at Johannes Gutenberg University of Mainz in Germany, reports in Nature.

“Thus, the nanoparticulate RNA immunotherapy approach introduced here may be regarded as a universally applicable novel vaccine class for cancer immunotherapy.”

Immunotherapy, which involves using the patient’s own immune system to attack cancer, isn’t in itself new – researchers are already using it against different cancer types with great results.

But until now, researchers have mostly done this by genetically engineering special, cancer-targeting immune cells in the lab, and then injecting them back into a patient – which is a time-consuming and expensive process.

The difference with this technique is that the vaccine is made in the lab, and it introduces the cancer DNA into the immune cells within the body, which is a lot less invasive. It also means that the vaccine can be tweaked to hunt a range of cancer types.

So why isn’t the immune system naturally taking out these cancer types?

“One reason is that cancer cells are similar in many ways to normal cells and the immune system avoids attacking the self,” explain Dutch immunologists Jolanda de Vries and Figdor in a commentary accompanying the Nature paper.

That means that when you develop a vaccine, you need to use an antigen – a foreign molecule that works like a ‘mugshot’ for the immune system – that’s not expressed in normal cells, too.

“Only relatively modest immune responses occur with vaccines containing antigens that are also expressed on healthy tissue,” write de Vries and Carl Figdor. “Strong immune responses can be expected only when cancer cells express antigens that are not usually expressed in normal adult cells.”

It’s this kind of cancer-specific antigen that the new vaccine is designed to deliver to the immune system. It works by coating the cancer RNA in a simple, fatty acid membrane, and giving it a slightly negative charge.

This means that once the vaccine is injected into a patient, it’s drawn via electric charge towards dendritic immune cells in the spleen, lymph nodes, and bone marrow.

These dendritic cells then ‘show’ the cancer RNA to the body’s T cells and, to anthropomorphise the situation, pretty much tell them, “Hey, this is the guy we’re after, go get him.” The goal is that the T cells will then go out and mass murder all the cancer cells in the body.

And this is what early research by the German team has demonstrated in mice. Once injected with the vaccine, the immune system was able to fight “aggressively growing” tumours, the research found.

Of course, many results in mice don’t translate to humans, so we can’t get too excited just yet.

The team has also now trialled a version of the vaccine in three patients with melanoma. The point of the trial was only to test whether the vaccine was safe to use in humans, not whether it was effective, and so far, the results are promising. The side effects were limited to flu-like symptoms, which is better than most chemotherapy treatments.

The team is now waiting 12 months for follow-up results from this safety trial, and if all goes well, will start a larger clinical trial after that to see if the vaccine really works.

“By combining laboratory-based studies with results from an early-phase clinical trial, this research shows that a new type of treatment vaccine could be used to treat patients with melanoma by boosting the effects of their immune systems,” Aine McCarthy, the senior science information officer at Cancer Research UK, told The Telegraph.

“Because the vaccine was only tested in three patients, larger clinical trials are needed to confirm it works and is safe, while more research will determine if it could be used to treat other types of cancer.”

Although it’s still very early days, we have another reason to feel hopeful about the future of cancer treatment. And that’s always a good thing.

See the full article here .

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From Science Alert: “Renewable energy now supplies almost a quarter of the world’s power needs”

Science Alert

BlackRockSolar/Flickr

7 JUN 2016
PETER DOCKRILL

Last year was an absolutely huge 12 months for renewable energy, with a new global status report on clean energy highlighting how 2015 was a record year for the industry – including the revelation that renewable energy can now satisfy nearly a quarter of the world’s power demands.

According to energy policy network REN21, record clean energy investments in 2015 drove the largest annual increase ever in renewable power generating capacity, with an estimated 147 gigawatts (GW) added to the global grid – suggesting that by the end of 2015, renewable capacity could shoulder 23.7 percent of global electricity requirements.

“What is truly remarkable about these results is that they were achieved at a time when fossil fuel prices were at historic lows, and renewables remained at a significant disadvantage in terms of government subsidies,” said REN21 executive secretary Christine Lins. “For every dollar spent boosting renewables, nearly 4 dollars were spent to maintain our dependence on fossil fuels.”

Among new investments in the renewable power sector, wind and solar represented the majority of growth, accounting for about 77 percent of new installations, with hydropower taking up most of the rest. Jobs in renewable energy increased, and now employ some 8.1 million people across the world.

“As renewables secure record investments year after year, we are seeing that it is local governments, communities, and citizens who are the real pioneers of this transition to a world powered by 100 percent renewable energy,” said senior program manager for climate energy, Anna Leidreiter, from the charity World Future Council. “Their support is logical really – renewable energy delivers impact locally and therefore most cities and communities see a huge benefit in investing in renewable sources to ensure that revenues stay in the region.”

Overall, global investments in clean energy hit US$285.9 billion (not counting large-scale hydropower stations), topping 2014’s $273 billion – a year in which 19.2 percent of the world’s consumption of energy was provided by renewables.

China is driving this growth, accounting for more than one-third of global investments in renewable energy, with the US, Japan, the UK, and India rounding out the top five nations.

In terms of overall power capacity sourced from renewables, not including hydropower, China again leads, trailed by the US, Brazil, Germany, and Canada. But if you look at the capacity of renewable power per capita, the field looks pretty different: Denmark leads, then Germany, Sweden, Spain, and Portugal.

It’s awesome to see renewable energy making such great strides, but the report’s authors warn against becoming complacent, saying there are still significant barriers keeping clean energy from even faster adoption.

“The renewables train is barrelling down the tracks, but it’s running on 20th century infrastructure – a system based on outdated thinking where conventional baseload is generated by fossil fuels and nuclear power,” said chair of REN21, Arthouros Zervos. “To accelerate the transition to a healthier, more-secure, and climate-safe future, we need to build the equivalent of a high-speed rail network – a smarter, more flexible system that maximises the use of variable sources of renewable energy.”

You can find out more about in the report and the state of renewable energy in 2016 in the video below.

Access mp4 video here .

See the full article here .

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From Science Alert: “Stephen Hawking’s finally published a solution to the black hole information paradox”

Science Alert

7 JUN 2016
FIONA MACDONALD

ESA/V. Beckmann (NASA-GSFC)

What??

Stephen Hawking made headlines back in January when he told the world he’d found a possible solution to his black hole information paradox – or in other words, he’d come up with a potential explanation for how black holes can simultaneously erase information and retain it.

Back then, he put his paper up on pre-print site arXiv.org, so the rest of the physics community could poke holes in it, and now, almost six months later, the research has finally been published in a peer-reviewed journal – and it suggests that we might actually be getting closer to figuring out this problem once and for all.

To understand why this is such a big deal, and what the black hole information paradox really is, we need to go back to where it all started.

Our original understanding of black holes, according to Einstein’s generally theory of relativity, is that everything that crosses the event horizon – the boundary of a black hole – is lost forever. Even light can’t escape its clutches, which is why black holes are called black holes (and also why it’s impossible for us to actually see one).

But then in the 1970s, Hawking proposed that radiation actually can escape from a black hole, because of the laws of quantum mechanics. Put very simply, he suggested that when a black hole swallows one half of a particle-antiparticle pair, the other particle radiates away into space, stealing a little energy from the black hole as it leaves.

Because of this, eventually, black holes can disappear, and the only remaining trace would be the electromagnetic radiation they emitted – which is known as ‘Hawking radiation’.

The problem is that, according to Hawking’s best calculations, that radiation would contain no useful information about what the black hole ate – the information swallowed up would have been lost forever. And that doesn’t gel with our understanding of modern physics, which states that it’s always possible to reverse time. In theory, at least, processes in the Universe will look the same if they’re running forwards or backwards.

As Dennis Overbye explains over at The New York Times:

“The Universe, like a kind of supercomputer, is supposed to be able to keep track of whether one car was a green pickup truck and the other was a red Porsche, or whether one was made of matter and the other antimatter. These things may be destroyed, but their ‘information’ – their essential physical attributes – should live forever.”

Hence the paradox. And it’s actually a big deal not just for astrophysicists, because if the rules of quantum mechanics don’t hold up for black holes, then what’s to say they apply to the rest of us?

But Hawking thinks he finally has a solution to the problem – black holes might actually have a halo of ‘soft hair’ surrounding them, which are capable of storing information.

That ‘hair’ isn’t actually hair – as you might have already assumed – but is actually low-energy quantum excitations that carry with them a signature pattern of everything that’s been swallowed up by the black hole, long after it evaporates.

“That pattern, like the pixels on your iPhone or the wavy grooves in a vinyl record, contains information about what has passed through the horizon and disappeared,” writes Overbye.

To come to this conclusion, Hawking identified two underlying problems with his original assumptions, which is why he says his original calculations – which suggested that the information inside a black hole would be lost forever – were wrong.

Those two assumptions were that the vacuum in quantum gravity is unique, and that black holes have no quantum ‘hair’. That’s getting a little complex, but what you need to know is that Hawking has since revised his calculations, and is fairly sure that black holes have ‘soft hair’ haloed around them.

This hypothesis has now been peer-reviewed and published in Physical Review Letters, and researchers are claiming that, while there’s more work to be done, it’s a promising step towards solving the information paradox.

“It is important to note that this paper does not solve the black hole information problem,” writes physicist Gary Horowitz from the University of California, Santa Barbara, in an accompanying commentary.

“First, the analysis must be repeated for gravity, rather than just electromagnetic fields. The authors are currently pursuing this task, and their preliminary calculations indicate that the purely gravitational case will be similar,” he adds. “More importantly, the soft hair they introduce is probably not enough to capture all the information about what falls into a black hole.”

His criticism is that it’s still unclear whether all the information swallowed up by a black hole really can be transferred to the soft hair – rather than just an energy signature of everything that’s been lost.

But he admits: “It is certainly possible that, following the path indicated by this work, further investigation will uncover more hair of this type, and perhaps eventually lead to a resolution of the black hole information problem.”

And that would certainly be a red-letter day in physics. Because we’d be one step closer to understanding some of the biggest enigmas in the known Universe – the weirdness that are black holes.

What does that mean for the rest of us? As Hawking explained in a talk last year: “[Black holes] are not the eternal prisons they were once thought. If you feel you are trapped in a black hole, don’t give up. There is a way out.”

And there might just be a little trace of you lingering on the outside, too.

See the full article here .

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From Science Alert: “Scientists discover magma building up below a town in New Zealand”

Science Alert

6 JUN 2016
FIONA MACDONALD

The nearby Mount Tarawera. Image: Carl Lindberg/Wikimedia

Scientists have discovered magma building up beneath a town on New Zealand’s North Island, and say it could signal the birth of a brand new volcano.

Since 1950, the researchers report that enough magma to fill 80,000 Olympic-size swimming pools has forced itself beneath the surface of the coastal town of Matata, about 200 kilometres southeast of Auckland, pushing the land up by 40 cm.

The good news is that the researchers aren’t predicting an eruption any time soon – volcanoes take thousands of years to form, so it’s still early days yet. But the discovery helps to explain a flurry of recent earthquakes in the region, and provides brand new insight into how volcanoes form.

The results were unexpected, because the town hasn’t had an active volcano nearby for at least 400,000 years, and is outside of any active volcanic regions. “It was quite a big surprise,” lead researcher Ian Hamling told Nick Perry for the Associated Press (AP).

Matata is home to around 650 people, and got the attention of geologists after experiencing higher than usual earthquake activity over the past decade.

They’d assumed this was due to some interesting tectonic plate activity, but after mapping the geological changes in the area over more than 60 years, the team showed that they’re likely to be caused by magma stressing and breaking rock as it builds up below the region.

They calculate that the magma pool is still around 9.5 km below the surface, so isn’t at risk of erupting in the near future, and might not even turn into a volcano at all – the magma might cool and harden instead. But monitoring the activity over the coming decades will greatly improve our understanding of how this process works.

You can see an illustration of what the researchers predict is going on below:

Ian Hamling

That’s particularly exciting for scientists, given that the town is just on the outskirts of the Taupo Volcanic Zone – one of the most active volcanic regions in the world.

“Although the ultimate fate of the magma remains unclear, its presence may represent the birth of a new magma chamber on the margins of arguably the world’s most active region of silicic volcanism, which has witnessed 25 caldera-forming eruptions over the last 1.6 million years,” the researchers write in Science Advances.

To figure out what was going on below the surface, the team used a range of satellites to scan in detail the changes to the region since 1950.

Along with regular GPS mapping, they used a system called interferometric synthetic aperture radar (or InSAR) to bounce radars at the region and measure the pattern at which they come back – allowing them to see centimetre scale changes in the elevation.

Using this data, the team found that an area of land about 400 square kilometres had risen by 40 centimetres since 1950, which suggests that a giant pool of magma is forming beneath the surface. And between 2004 and 2011, the uplift was particularly rapid, which correlated with a series of thousands of small earthquakes in the region.

The team now hopes to use this data to not only understand more about volcano formation, but to create better warning systems for the magma-triggered quakes in future.

Although the researchers are fairly confident with their results, over half of the area they’re looking into is located offshore, which means the team can’t scan surface level changes, and had to apply the information gained from the land-based region to this area too, which means there’s room for error.

Still, Victoria Miller, a volcanologist with Geoscience Australia, who wasn’t involved in the research, said it was a pretty exciting find worthy of more investigation. “The scientific analysis seems robust and notes the limitations of modelling an offshore source,” Miller told AP.

See the full article here .

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From Science Alert: “Chile is producing so much solar power, it’s giving it away for free”

Science Alert

3 JUN 2016
DAVID NIELD

Anyaivanova/Shutterstock.com

Market forces often produce strange quirks in the economic system, like the one we’re seeing in Chile this year: the country is producing so much solar power that it’s being sold for… nothing at all.

While it’s incredibly encouraging to see so much expansion in the country’s renewable energy output, this huge amount of supply does actually cause problems for the companies looking to invest in solar energy.

Solar capacity on Chile’s central power grid (called SIC or Sistema Interconectado Central) has more than quadrupled over the past three years to 770 megawatts – good news for the environment and customers paying their electricity bills.

Now the challenge is to upgrade the infrastructure to cope with the influx of solar energy.

As Vanessa Dezem and Javiera Quiroga report at Bloomberg, spot prices (set by supply and demand) for electricity have hit zero for 113 days this year up to the end of April. That compares with 192 days in total in 2015.

Increasing energy demands and investment followed by a slowing of economic growth means that regions are being oversupplied with power – 29 solar farms are now online in the country with a further 15 in the pipeline.

It’s fantastic to see so much solar energy being produced, but next-to-nothing prices will discourage future investment and mean power plants just aren’t profitable, warn experts.

The solution lies in increasing the country’s ability to take on extra capacity, and there are plans to build a 3,000-kilometre (1,854-mile) transmission line to link the SIC with Chile’s northern power network for the first time.

Once this is built, it’ll mean that, when there is a surplus, it can be re-routed to areas that need it. Basically it’s just increasing the demand on the sustainable product by giving more people access to it.

There are also transmission lines within the two grids that need to be upgraded to allow electricity to be more evenly distributed.

Chile is way ahead of other countries in Latin America when it comes to renewable energy capacity – producing more than the rest of the continent combined, according to Bloomberg’s figures – which is partly helped by the abundance of sunshine, wind, and water in the country.

But they’ve also invested in some awesome technology that are helping them maximise these natural resources. One of the biggest renewable energy sources in the country is the Atacama-1 solar tower, in the middle of the Atacama desert.

Standing more than 200 metres (656 feet) tall, the US$1.1 billion project uses mirrors to concentrate sunlight onto a steel solar receiver that weighs 2,000 tonnes, as Jonathan Watts reports for The Guardian. Thanks to 10,600 heliostatic mirrors and 50,000 tonnes of molten salt, the tower will eventually be able to supply electricity around the clock.

As well as upgrading its infrastructure to support projects like Atacama-1, Chile has plans to export its solar power energy too: “We are in a region of the world that has huge opportunities for integration and interconnection,” Chile’s Energy Minister Maximo Pacheco told Bloomberg.

This is something that countries like Denmark, which has a lot of wind energy production, does in order to maintain the price of wind power even when there’s a surplus.

“There are huge opportunities for Chile… [to] export some of this renewable energy to other countries in the region,” added Pacheco.

What’s exciting is that we’re halfway there – we’re getting so much better at harnessing renewable energy, now we just need to find out a way to make it a good idea economically.

See the full article here .

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From Science Alert: “Gravitational waves could reveal a stringy universe, say physicists”

Science Alert

3 JUN 2016
DAVID NIELD

AbstractUniverse/Shutterstock.com

Time to brush up on your string theory?

Back in February, physicists gave us one of the most exciting scientific discoveries of the century – the first direct evidence of gravitational waves.

Gravitational wave Henze NASA

These waves are like ripples that expand after a major event in space, such as two black holes merging or the explosion of a massive star.

The discovery gave us a whole new way of looking at the Universe, and that’s something two physicists in Spain are taking advantage of, by testing out another scientific hypothesis: string theory. And if their ideas are correct, it could fundamentally change our thinking about the nature of the Universe.

First off, it’s important to understand how gravitational waves work. In the very early Universe, everything was much denser than it is now, which resulted in a great deal of light scattering. Those photon signals can be a big problem when it comes to peering deep into the Universe to look back in time, because there’s so much background noise to take into account.

What makes gravitational waves special is that their movements don’t appear to be affected by interfering electrons and protons. In fact, gravitational waves might allow us to observe objects and events that don’t emit any light at all, including the cosmic ‘strings’ that underlie the famous string theory hypothesis.

String theory aims to provide a unified approach to explaining the fundamental structure of the Universe. It suggests that cosmic strings – incredibly long and thin defects in the curvature of space and time – formed right after the Big Bang. Unfortunately, these cosmic strings are thought to have been obliterated many aeons ago, so find a large number of them, we’d have to go back to the earliest moments of the Universe.

And that brings us back to gravitational waves. Physicists Isabel Fernandez-Nunez and Oleg Bulashenko of the University of Barcelona think that one could lead us to the other – gravitational waves could help us find cosmic strings.

Fernandez-Nunez and Bulashenko started off by picturing a string as a sharp crease in space-time, and then calculated how a gravitational wave would pass through that crease. If we can find wave ripples that match these calculations, then we might have evidence of a cosmic string, they suggest.

There are hurdles to overcome before we can test out their hypothesis, because right now, we don’t have the kind of technology to measure gravitational waves in the way that the pair’s hypothesis requires.

[Here is what we have:

LIGO map

Caltech/MIT Advanced aLigo detector in Livingston, LA, USA and Caltech/MIT Advanced Ligo Hanford, WA, USA, which work in tandem.

ESA/LISA Pathfinder spacecraft, prelude to ESA/LISA

Future ESA/eLISA

NASA/Fermi Telescope

Event Horizon Telescope Array

Event Horizon Telescope map

Arizona Radio Observatory/Submillimeter-wave Astronomy (ARO/SMT)

Atacama Pathfinder EXperiment (APEX)

Combined Array for Research in Millimeter-wave Astronomy (CARMA)

Atacama Submillimeter Telescope Experiment (ASTE)

Caltech Submillimeter Observatory (CSO)

Institut de Radioastronomie Millimetrique (IRAM) 30m

James Clerk Maxwell Telescope interior, Mauna Kea, Hawaii, USA

Large Millimeter Telescope Alfonso Serrano

Submillimeter Array Hawaii SAO

Future Array/Telescopes

ESO/NRAO/NAOJ ALMA Array, Chile

Plateau de Bure interferometer

South Pole Telescope SPTPOL]

But these are still early days for gravitational wave astronomy, so scientists are still sharing ideas about how we might be able to make the most of this discovery.

The researchers’ paper is available on pre-print website, arXiv.org, but has yet to be peer-reviewed by other astrophysicists, so we’ll have to wait and see what the community makes of their hypothesis before we can get too excited. That said, this isn’t the first time that scientists have speculated that gravitational waves could lead us to cosmic strings.

B.S. Sathyaprakash from Cardiff University in the UK, who works at the observatory where gravitational waves were first measured, thinks a lot of new such discoveries could be just around the corner. “I am pretty confident that within the next three or four years we will be making detections one by one and ticking the boxes,” he told Tim Radford at The Guardian.

Plus we’d also have to be very lucky to find a pattern of just the right intensity from our position on Earth.

See the full article here .

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From Science Alert: “What’s the mass of the entire Milky Way? Astrophysicists finally have an answer” – Women in Science

Science Alert

3 JUN 2016
PETER DOCKRILL

Milky Way NASA/JPL-Caltech /ESO R. Hurt

If you’re the kind of person who worries about how accurate (or perhaps not) your creaky bathroom scales might be, spare a thought for astrophysicist Gwendolyn Eadie. It’s her job – or, rather, area of study – to figure out the mass of the whole galaxy.

No easy gig, to be sure, but according to Eadie’s latest estimates, we now have a new measurement for the mass of the Milky Way, and it’s a biggie. She calculates that the Milky Way has a mass equal to 7 x 10^11 solar masses. To put it another way, the galaxy has the same mass as 700 billion Suns. “And our galaxy isn’t even the biggest galaxy,” Eadie says.

To drill down a little further, the Sun has about 330,000 times the mass of Earth, or 2 nonillion kilograms (that’s a 2 followed by 30 zeroes).

Yep, these are some pretty crazy numbers, but astronomical mass estimations like this are an important part of figuring out how the Milky Way came to be – and where it’s headed.

“Understanding our galaxy’s mass puts it into a better cosmological context,” Eadie, a PhD student from McMaster University in Canada, told Michelle Z. Donahue at National Geographic. “People who study the evolution of galaxies look at how the mass relates to its evolution. If we have a better handle on what the mass of the Milky Way is, we can understand how it and other galaxies form and evolve.”

There’s a lot to take stock of in these kinds of calculations. The mass of a galaxy includes all its stars, planets, and moons, plus gases, dust, and other cosmic material. And that’s just the visible matter – let’s not forget dark matter, something we still know very little about, but which scientists think exerts a gravitational force on all the non-dark matter around it.

To make matters worse, getting a handle on the visible objects we can actually see is complicated by the fact that we’re located amidst all the matter we’re trying to measure.

“The fact that we sit inside the galaxy does introduce some difficulties,” Eadie told Tim Radford at The Guardian. “We have a heliocentric perspective: we see everything from the perspective of our Sun’s position (and movement) through the galaxy. It’s important that we take the movement and position of the Sun into account when we measure the motions and positions of other objects in the Milky Way.”

Together with fellow researcher and supervisor William Harris, Eadie devised a new way for calculating the movement and velocity of globular clusters – spherical groups of stars that act like satellites, orbiting the galactic core.

The new technique, which helps fill in the gaps on what we don’t know about some globular cluster velocities, provides what the researchers think is the most accurate estimation yet of the total galactic mass. Prior to the 700 billion Suns calculation, estimates varied between the mass of 100 billion Suns to 1 trillion.

“We can also compare the total mass estimate to the amount of visible matter that we see in the Milky Way and then get a prediction for the amount of dark matter,” Eadie told The Guardian. “With our estimate, it seems that dark matter makes up about 88 percent of the Milky Way’s mass.”

The findings* were presented at the annual meeting of the Canadian Astronomical Society this week and have been submitted to The Astrophysical Journal.

The research hasn’t been accepted for publication yet, so we’ll have to wait for it to be peer-reviewed before we can start adding it to textbooks and the like, but it’s already drawing praise from some within the astrophysics community.

“Figuring out how fast, and in what direction, globular clusters are moving is pretty hard. Combining all of these data together in a consistent model for the Milky Way is a real challenge,” Alan McConnachie from Canada’s Herzberg Institute for Astrophysics, who wasn’t involved with the study, told National Geographic. “This work is a big step toward being able to claim with confidence that we know how massive our home actually is.”

*No science paper yet.

See the full article here .

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From Science Alert: “Scientists just made big progress in fighting this incurable form of brain cancer”

Science Alert

This post is dedicated to E.B.M., cancer researcher. I hope that he or his parents see it.

27 MAY 2016
DAVID NIELD

Because chemo is just not good enough.

Researchers working on a more effective treatment for brain tumours have achieved such amazing results, they thought there was an error in their calculations. But the results are real: and the implications could be huge.

By using an organic ‘nanocarrier’ to deliver chemotherapy drugs directly to tumours in the brain, the scientists have been able to achieve significant improvements in the number of cancer cells being killed off.

The technique has so far only been tested in mice, but if replicated in humans – which, to be clear, is no easy feat – it could eventually lead to new treatments for people with specific types of brain cancer.

Lead researcher and radiologist Ann-Marie Broome at the Medical University of South Carolina has been targeting glioblastoma multiforme (GBM) – a particularly stubborn form of cancer that’s currently incurable.

Its position in the brain makes it difficult to operate on, and the blood-brain barrier (designed to protect the brain from harm) means that getting an effective dose of drugs to the tumour isn’t easy.

A schematic sketch of blood vessels in the brain.
Date March 2009
Armin Kübelbeck

That’s where this new nanotechnology approach comes in. Broome and her colleagues used what they already knew about GBM and platelet-derived growth factor (PDGF) – which regulates cell growth and division – to create their new nanocarrier, built from an aggregate of molecules.

The carrier, technically known as a micelle, is small enough to cross the brain-blood barrier to apply the treatment directly. The researchers describe it as using a postal code to get the drugs to the right place – the micelle gets the dose to the right street, and then the PDGF is used to find the right house.

“I was very surprised by how efficiently and well it worked once we got the nanocarrier to those cells,” says Broome. “When we perfect this strategy, we will be able to deliver potent chemotherapies only to the area that needs them.”

“This will dramatically improve our cure rates while cutting out a huge portion of our side effects from chemotherapy,” she adds. “Imagine a world where a cancer diagnosis not only was not life-threatening, but also did not mean that you would be tired, nauseated, or lose your hair.”

The brain tumour’s own natural chemistry actually gives the micelle nanocarriers their potency. As the tumour grows, it creates waste by-products that cause acidity in the blood, which triggers the release of the micelle’s payload.

“It’s very important that the public recognise that nanotechnology is the future,” said Broome. “It impacts so many different fields. It has a clear impact on cancer biology and potentially has an impact on cancers that are inaccessible, untreatable, undruggable – that in normal circumstances are ultimately a death knell.”

Now that the researchers have shown that nanocarrier delivery is possible – at least in mice – they need to test a wider range of drugs against a wider range of cancers. If all goes well, hopefully we’ll hear about clinical trials involving humans later on down the track.

There’s obviously a ways to go before this technique will become available to treat cancer in people, but nanotechnology has been showing promising results in previous studies, so this might just be how we end up fighting the disease in the future.

The findings have been published in Nanomedicine.

See the full article here .

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From Science Alert: “Physicists just found a link between dark energy and the arrow of time”

Science Alert

20 MAY 2016
BRENDAN COLE

For years, physicists have attempted to explain dark energy – a mysterious influence that pushes space apart faster than gravity can pull the things in it together. But physics isn’t always about figuring out what things are. A lot of it is figuring out what things cause.

And in a recent paper*, a group of physicists asked this very question about dark energy, and found that in some cases, it might cause time to go forward.

When you throw a ball into the air, it starts with some initial speed-up, but then it slows as Earth’s gravity pulls it down.

Spacetime with Gravity Probe B. NASA

NASA/Gravity Probe B

If you throw it fast enough (about 11 km per second, for those who want to try), it’ll never slow down enough to turn around and start falling back towards you, but it’ll still move more slowly as it moves away from you, because of Earth’s gravity.

Physicists and astronomers in the 1990s expected something similar to have occured after the big bang – an event that threw matter out in all directions. The collective gravity from all that matter should have slowed it all down, just like the Earth slows down the ball. But that’s not what they found.

Instead, everything seems to have sped up. There’s something pervading the Universe that physically spreads space apart faster than gravity can pull things together. The effect is small – it’s only noticeable when you look at far-away galaxies – but it’s there. It’s become known as dark energy – “dark”, because no one knows what it is.

Dark energy depiction. Image: Volker Springle/Max Planck Institute for Astrophysics/SP)

Science is nothing if not the process of humans looking for things they can’t explain, so this isn’t the first time the Universe has stumped us. For centuries, one of those stumpers has been time itself: Why does time have an arrow pointing from the past to the present to the future?

It might seem like a silly question – I mean, if time didn’t go forward, then effects would precede causes, and that seems like it should be impossible – but it’s less of one than you might think.

The Universe, as far as we can tell, only operates according to laws of physics. And just about all of the laws of physics that we know are completely time-reversible, meaning that the things they cause look exactly the same whether time runs forward or backward.

One example is the path of a planet going around a star, which is governed by gravity. Whether time runs forward or backward, planetary orbits follow the exact same paths. The only difference is the direction of the orbit.

But one important piece of physics isn’t time-reversible, and that’s the second law of thermodynamics. It states that as time moves forward, the amount of disorder in the Universe will always increase. Just like dark energy, it’s something we’ve noticed about the Universe, and it’s something that we still don’t totally understand – though admittedly we have a better idea of it than we do of dark energy.

Physicists have, for this reason, reluctantly settled on the second law as the source of time’s arrow: disorder always has to increase after something happens, which requires that time can only move in one direction.

So physicists A. E. Allahverdyan from the Yerevan Physics Institute and V. G. Gurzadyan from Yerevan State University, both in Armenia, decided to see if – at least in a limited situation – dark energy and the second law might be related. To test it, they looked at the simple case of something like a planet orbiting a star with a changing mass.

They found that if dark energy either doesn’t exist or if it pulls space together, the planet just dully orbits the star without anything interesting happening. There’s no way to tell an orbit going forward in time from one going backward in time.

But if dark energy pushes space apart, like it does in our Universe, the planet eventually gets thrown away from the star on a path of no return. This gives us a distinction between the past and the future: run time one way, and the planet is flung off, run it the other way, and the planet comes in and gets captured by the star.

Dark energy naturally leads to an arrow of time.

The authors stress that this is a really limited situation, and they’re certainly not claiming dark energy is the reason time only ever moves forward. But they’ve shown a possible link between thermodynamics and dark energy that could help us to understand either – or maybe both – better than we ever have.

The research has been published in Physical Review E.

*Science paper:
Time arrow is influenced by the dark energy

See the full article here .

Please help promote STEM in your local schools.

Stem Education Coalition

From Science Alert: “Mount Everest isn’t really the tallest mountain on Earth”

Science Alert

20 MAY 2016
JOSH HRALA

Mt Everest. shrimpo1967/WikiCommons

Sorry, climbers.

Sir Edmund Hillary, uncredited photo, Wikipedia

Ever since Sir Edmund Hillary reached its peak back in 1953, thousands of adventures have set out to conquer the deadly summit of Mount Everest. In fact, so many people give it a shot every year that this Himalayan beauty is slowly turning into a literal pile of crap.

Everest owes its popularity to the impressive title of ‘highest mountain in the world’, but in reality, it isn’t – not according to science. Yup, the world’s highest mountain is actually Chimborazo – a stratovolcano in Ecuador that’s part of the Andes mountain range – because it’s the furthest point from Earth’s centre and, therefore, the highest in terms of distance.

Chimborazo volcano, the closest point to the sun. Riobamba, Ecuador. Author David Torres Costales
Date 27 September 2011

According to Eli Rosenberg for The New York Times, Chimborazo’s summit rises 20,500 feet (6,248 metres) above sea level, which is shorter than Everest by 8,529 feet (2,600 metres), but that all changes when measured from the centre of Earth.

Basically, since Earth isn’t flat (sorry, B.o.B), it bulges outward at the equator and flattens near the poles. This means that mountains near the equator are technically higher than those in other areas, and it just so happens that Chimborazo is almost smack-dab on our planet’s waistline, while Everest is 28 degrees north.

So how much higher is it? Well, according to one report, Everest stretches a distance of 3,965 miles (6,382 kilometres) from Earth’s centre. Meanwhile, Chimborazo stretches 3,967 miles (6,384 kilometres). Though it’s only a 2-mile (3.2 km) difference, it means everything when it comes to crowning height titles.

In fact, those 2 miles are enough to put Chimborazo at number one, and kick Everest out of the top 20.

This isn’t exactly news, though – NPR ran a report about Chimborazo back in 2007. So why does Everest continue to get all the love, while Chimborazo goes relatively unnoticed? Well, it all comes down to how hard the climb is.

If you’re a mountain climber, you want the hardest challenge, which is what Everest offers. It takes 10 days to merely make it to Everest’s base camp, six weeks to acclimatise, and then the arduous nine-day climb to the top. On the other hand, Chimborazo takes about two days to climb after acclimatising (about two weeks), reports Rosenberg.

Also, it’s important to mention again that Everest still takes the cake when measured at sea level. If you’re using that as a metric, Chimborazo wouldn’t even rank as the tallest peak in the Andes. That title belongs to Mount Aconcagua, which rises 22,828 feet (6,961 metres) above sea level.

South summit of Aconcagua with south face. December 1997. Albert Backer

So, if you’ve already made plans to climb Everest and earn your name a place alongside Sr Edmund Hillary’s, fear not, because you are still climbing the tallest mountain in the world (if sea level is your metric). After that, you might as well hit up Chimborazo, because that climb will seem like a walk in the park.

See the full article here .

Please help promote STEM in your local schools.

Stem Education Coalition