Hang in their just a few more years. SLS (and SpaceX's Heavy Falcon) are on their way. To the moon and beyond!
Tuesday, July 29, 2014
We're putting a forest on a climate-change fast-track
- 28 July 2014 by Adrian Barnett
- Magazine issue 2979. Subscribe and save
- For similar stories, visit the Interviews and Climate Change Topic Guides
An ambitious experiment that exposes a natural woodland to rising carbon dioxide levels will tell us what's in store for the world's trees, says Rob Mackenzie
You head the Birmingham Institute of Forest Research. How will it stand out?
One way it will stand out is a novel experiment called FACE – Free-Air Carbon Dioxide Enrichment. It will be the first in the world to take a mature, temperate, broad-leafed woodland ecosystem and, where it stands, expose it to predicted future atmospheric concentrations of carbon dioxide. We will look at the effects of the CO2 on the structure and functioning of the woodland.
With FACE we are responding to a lack of long-term data on the effects of CO2 on woodland. People have been saying we need something like this for a long time.
How long will the experiment last?
The FACE experiment has been on the wish-list of UK scientists for years, but has never been possible at this scale because of funding insecurities. Now we are in the extremely fortunate situation of having received philanthropic funding. This allows us to plan for an experiment lasting at least 10 years. If our results are as significant as we expect, then we should be able to extend the run beyond 10 years.
How far forward will it look?
The CO2 we will be adding corresponds to what we expect to be in the air 75 years from now at current rates of change.
How will you be monitoring the woodland?
We will be using developments in genomics to characterise biodiversity in unprecedented detail. For plant health we have a dedicated lab with the latest biomedical technology. And we will use the latest sensor technology to provide us with never-before-seen levels of detail about how semi-natural woodlands function.
Can't you just do all this in a lab?
You can learn a lot about how plants respond to changing CO2 using greenhouses, plant growth chambers, even cell lines. But in nature 1+1 has a habit of not equalling 2, so you need to take away the walls, the fake growing media, the artificial climate and watch actual nature working. FACE is Gaia science, if you like.
What else will the institute be looking at?
The other topic in the early years is figuring out the microbiology of pathogen threats to plants.
Why focus your research on these things?
We don't think it's possible to understand the true value of woodlands and forests if we are uncertain about how resilient they are to biological and environmental challenges. These threats include things like ash dieback disease and, of course, human-induced climate change.
How vital are experiments like this?
This is part of an emerging experimental array that will do for ecology what the great atom smashers and telescopes have done for physics. Ultimately, we aim to provide fundamental science, social science and cultural research of relevance to forests anywhere in the world.
This article appeared in print under the headline "Fast-forwarding forests"
Profile
Rob Mackenzie is the director of the newly established Birmingham Institute of Forest Research at the University of Birmingham in the UK, where he is also a professor of atmospheric science
Genetic moderation is needed to debate our food future
- 28 July 2014 by Susan Watts
- Magazine issue 2979. Subscribe and save
- For similar stories, visit the Food and Drink , Comment and Analysis and GM Organisms Topic Guides
GM is now a term loaded with baggage. Scientists must allow for people's objections to show the public there's nothing "spooky" about it
Susan Watts is a journalist and broadcaster. She was science editor of Newsnight until the post was closed
WITH food security firmly on the international agenda, there's a growing appetite to look again at the opportunities promised by agricultural biotechnology.
Scientists working in this area are excited by new techniques that enable them to edit plant DNA with unprecedented accuracy. Even epigenetic markers, which modulate the activity of genes, can now be altered. The promise is to modify crops to make them more nutritious or resistant to disease.
But there's a problem, notably in Europe: genetic modification.
Much of agricultural biotechnology – including conventional breeding – involves genetic modification of one kind or another. But "GM" has come to mean something quite specific, and is loaded with baggage. To many people it means risky or unnatural mixing of genes from widely disparate species, even across the plant and animal kingdoms, to create hybrids such as corn with scorpion genes. That baggage now threatens to undermine mature debate about the future of food production.
It is no longer a simple yes/no choice between high-tech agribusiness and conventional production driven by something ill-defined as more "natural".
The battle lines of this latest wave of agricultural advance are already being drawn. The UK's Biotechnology and Biological Sciences Research Council, for example, is working on a position statement on the new technologies, which it expects to release later this summer.
It is clear that, over the coming years, the general public will have to decide which of these technologies we find acceptable and which we do not.
So where did it all go wrong to begin with? In the late 1990s, when I was reporting on early GM research for the BBC's current affairs programme Newsnight, anti-GM protestors realised that vivid images made good TV and rampaged through fields in white boiler suits destroying trial crops.
On the other side, industry representatives brushed aside public concerns and tried to control the media message, thumping the table in the office of at least one bemused newspaper editor (who went on to co-script a TV drama about a darker side to GM). They also lobbied hard for the relaxation of regulations governing agribusiness.
In the middle was the public, just coming to terms with farming's role in the BSE crisis. There was little space for calm, rational debate. Instead, GM became the cuckoo in the nest of agricultural biotechnology and its industry backers became ogres, shouting down any discussion of alternatives.
As a result, many people remain unaware that there are other high-tech ways to create crops. Many of these techniques involve the manipulation of genes, but they are not primarily about the transfer of genes across species.
But for GM to be discussed alongside such approaches as just another technology, scientists will have to work harder to dispel the public's remaining suspicions.
I recently chaired a debate on biotech at the UK's Cambridge Festival of Plants, where one audience member identified a public unease about what he called the slightly "spooky" aspect of GM crops. He meant those scorpion genes, or fish genes placed into tomatoes – the type of research that helped to coin the phrase "yuck factor".
To my surprise, a leading plant scientist on the panel said she would be prepared to see cross-species manipulation of food crops put on hold if the public was overwhelmingly uncomfortable with it. Ottoline Leyser, director of the University of Cambridge's Sainsbury Laboratory, said she believed valuable GM crop development could still be done even if scientists were initially restricted to species that can swap their genes naturally, outside of the laboratory. An example of this might be adding a trait from one variety of rice to another.
Nevertheless, Leyser remains adamant that there is "nothing immensely fishy about a fish gene". What's more, she added, the notion of a natural separation between species is misplaced: gene-swapping between species in the wild is far more prevalent than once thought.
But Leyser insisted that scientists must respect the views of objectors – even if "yuck" is their only complaint. That concession from a scientist is unusual. I've spoken to many of her peers who think such objections are irrational.
Scientists cannot expect people to accept their work blindly and they must make time to listen. Above all, more of them should be prepared to halt experiments that the public is uncomfortable with. And it's beginning to happen.
Paul Freemont is co-director of the Centre for Synthetic Biology and Innovation at Imperial College London. He designs organisms from scratch but would be prepared to discontinue projects that the public is unhappy about. He says scientists need an occasional reality check.
"We are going to have to address some of the consequences of what we're doing, and have agreements about what's acceptable to society in terms of manipulating biology at this level," Freemont says.
Scientists funded with public money may already feel some obligation to adopt this approach. But those working in industry should consider its advantages too. A more open and engaged conversation with the public could surely benefit the companies trying to sell us novel crop technologies.
Society, for its part, will need to listen to the experts with an open mind. And as we work out how to feed an expanding population, we will need to ask questions that are bigger than "GM: yes or no?"
This article appeared in print under the headline "Genetic moderation"
Susan Watts is a journalist and broadcaster. She was science editor of Newsnight until the post was closed
Strange dark stuff is making the universe too bright
- 17 July 2014 by Lisa Grossman
- Magazine issue 2978. Subscribe and save
- For similar stories, visit the Cosmology Topic Guide
LIGHT is in crisis. The universe is far brighter than it should be based on the number of light-emitting objects we can find, a cosmic accounting problem that has astronomers baffled.
"Something is very wrong," says Juna Kollmeier at the Observatories of the Carnegie Institution of Washington in Pasadena, California.
Solving the mystery could show us novel ways to hunt for dark matter, or reveal the presence of another unknown "dark" component to the cosmos.
"It's such a big discrepancy that whatever we find is going to be amazing, and it will overturn something we currently think is true," says Kollmeier.
The trouble stems from the most recent census of objects that produce high-energy ultraviolet light.
Some of the biggest known sources are quasars – galaxies with actively feeding black holes at their centres. These behemoths spit out plenty of UV light as matter falling into them is heated and compressed. Young galaxies filled with hot, bright stars are also contributors.
Ultraviolet light from these objects ionises the gas that permeates intergalactic space, stripping hydrogen atoms of their electrons. Observations of the gas can tell us how much of it has been ionised, helping astronomers to estimate the amount of UV light that must be flying about.
But as our images of the cosmos became sharper, astronomers found that these measurements don't seem to tally with the number of sources found.
Kollmeier started worrying in 2012, when Francesco Haardt at the University of Insubria in Como, Italy, and Piero Madau at the University of California, Santa Cruz, compiled the results of several sky surveys and found far fewer UV sources than previously suggested.
Then in February, Charles Danforth at the University of Colorado, Boulder, and his colleagues released the latest observations of intergalactic hydrogen by the Hubble Space Telescope. That work confirmed the large amount of gas being ionised. "It could have been that there was much more neutral hydrogen than we thought, and therefore there would be no light crisis," says Kollmeier. "But that loophole has been shut."
Now Kollmeier and her colleagues have run computer simulations of intergalactic gas and compared them with the Hubble data, just to be sure. They found that there is five times too much ionised gas for the number of known UV sources in the modern, nearby universe.
Strangely, their simulations also show that, for the early, more distant universe, UV sources and ionised gas match up perfectly, suggesting something has changed with time (Astrophysical Journal Letters, doi.org/tqm).
This could be down to dark matter, the mysterious stuff thought to make up more than 80 per cent of the matter in the universe.
The leading theoretical candidates for dark matter are weakly interacting massive particles, or WIMPs. There are many proposed versions of WIMPs, including some non-standard varieties that would decay and release UV photons.
Knowing that dark matter in the early universe worked like a scaffold to create the cosmic structure we see today, we have a good idea how much must have existed in the past. That suggests dark matter particles are stable for billions of years before they begin to decay.
Theorists can now consider the UV problem in their calculations and see if any of the proposed particles start to decay at the right time to account for the extra light, says Kathryn Zurek, a dark matter expert at the University of Michigan in Ann Arbor. If so, that could explain why the excess only shows up in the modern cosmos.
If WIMPS aren't the answer, the possible explanations become even more bizarre, such as mysterious "dark" objects that can emit UV light but remain shrouded from view. And if all else fails, there's even a chance something is wrong with our basic understanding of hydrogen.
"We don't know what it is, or we would be reporting discovery instead of crisis," says Kollmeier.
"The point is to bring this to everyone's attention so we can figure it out as a community."
This article appeared in print under the headline "Why is the cosmos too bright to bear?"
Psychedelic cells are fruit of Alan Turing's equations
- 29 July 2014 by Jacob Aron
- Magazine issue 2979. Subscribe and save
- For similar stories, visit the Picture of the day and Books and Art Topic Guides
(Image: Jonathan McCabe)
WE ALL know the world can look weird and wonderful under the microscope, but who knew cells could look this pretty? Actually, you won't find these psychedelic blobs in any living creature on Earth, because contrary to appearances this image has been created by a computer.
Generative artist Jonathan McCabe works with algorithms first developed by mathematician Alan
Turing to create pictures like this. "I don't guide the production of any particular image, the program runs from start to finish without input," McCabe says, though he does tweak the software to produce different results. "The trick is to try to make a system that generates interesting output by itself."
Turing is most famous for his pioneering work in computing
, but he was also interested in how living creatures produce biological patterns such as a tiger's stripes. He came up with a system of equations that describe how two chemicals react together, resulting in surprisingly lifelike arrangements.
, but he was also interested in how living creatures produce biological patterns such as a tiger's stripes. He came up with a system of equations that describe how two chemicals react together, resulting in surprisingly lifelike arrangements.
McCabe developed his algorithm based on Turing's ideas. His program treats colours as different liquids that can't mix together because of an artificial surface tension, which is what gives them a cell-like appearance. "You get structures which look like cell membranes and mitochondria because at the microscopic scale surface tension forces are strong," says McCabe.
This article appeared in print under the headline "Rise of the blobs"
Cagey material acts as alcohol factory
2 hours ago by Kate Greene
"Hydrocarbons like ethane and methane could be used as fuel, but they're hard to store and transport because they're gases," says Dianne Xiao, graduate student at the University of California Berkeley.
"But if you have a catalyst that can selectively turn them into alcohols, which are much easier to transfer and store," she says, "that would make things a lot easier."
Xiao and Jeffrey Long, scientist in Berkeley Lab's Materials Sciences Division and professor of chemistry at the UC Berkeley, focused this project on converting ethane to ethanol.
Ethanol is a potential alternative fuel that burns cleaner and has a higher energy density than other alternative fuels like methanol. One problem with ethanol, however, is that current methods for production require extreme heat, which makes it expensive.
The innovation came when Long and Xiao designed a material called Fe-MOF-74, in a class of materials called metal-organic frameworks or MOFs. Because of their cage-shaped structures, MOFs boast a high surface area, which mean they can absorb extremely large amounts of gas or liquid compared to the weight of the MOF itself.
Since MOFs are essentially structured like a collection of tiny cages, they can capture other molecules, acting as a filter. Additionally, they can perform chemistry as molecules pass through the cages, becoming little chemical factories that convert one substance to another.
It's this chemical-conversion feature of MOFs that Long and Xiao took advantage of. Ethane is a molecule made of two carbon atoms where each atom is surrounded by atoms of hydrogen. Ethanol is also made of two carbon atoms bonded to hydrogen atoms, but one of its carbon atoms is also bonded to a hydrogen-oxygen ion called a hydroxyl.
Previous attempts to add a hydroxyl ion to ethane to make ethanol have required high pressure and high temperatures that range from 200 to 300 degrees Celsius. It's costly and inconvenient.
But by using a specially designed MOF—one in which a kind of iron was added inside the tiny molecular cages—the researchers were able to reduce the need for extreme heat, converting ethane to alcohol at just 75 degrees Celsius.
"This is getting toward a holy grail in chemistry which is to be able to cleanly take alkanes to alcohols without a lot of energy," says Long. Long and Xiao worked closely with researchers at the National Institute of Standards and Technology, the University of Minnesota, the University of Delaware, and the University of Turin to design, model, and characterize the MOF and resultant ethanol production.
Next steps involve tweaking the concentrations of iron in the MOF to produce a more efficient conversion, says Xiao. "It's a promising proof of principle," she says. "It's exciting that we can do this now at low temperature and low pressures."
More information: "Oxidation of ethane to ethanol by N2O in a metal–organic framework with coordinatively unsaturated iron(II) sites." Dianne J. Xiao, et al. Nature Chemistry 6, 590–595 (2014) DOI: 10.1038/nchem.1956. Received 17 December 2013 Accepted 14 April 2014 Published online 18 May 2014
Journal reference: Nature Chemistry
Read more at: http://phys.org/news/2014-07-cagey-material-alcohol-factory.html#jCp Read more at: http://phys.org/news/2014-07-cagey-material-alcohol-factory.html#jCp
Direct reaction heavy atoms to catalyst surface demonstrated
1 hour ago
Most chemical reactions on a material surface (catalyst) follow the Langmuir-Hinshelwood scheme: atoms from the surroundings adhere to the material and move randomly across the surface until they meet each other. At that spot the atoms react with each other and are subsequently released from the surface. In Eley-Rideal reactions a particle on the surface instead reacts directly with an atom from the surroundings that is rapidly moving past it. According to the theory, this type of reaction takes place most easily with light, rapidly moving atoms. In practice, the Eley-Rideal reaction has only been demonstrated with the lightest atom, hydrogen. The team from DIFFER, the Materials innovation institute M2i and the Van 't Hoff Institute for Molecular Sciences in Amsterdam have now demonstrated for the first time that heavier atoms such as nitrogen and oxygen can also undergo an Eley-Rideal reaction.
"In our set-up, Harpoen, we can directly observe the difference between the two types of reaction", explains research leader Dr Teodor Zaharia. His team covered a surface of ruthenium with a layer of oxygen atoms and fired a focused beam of nitrogen atoms at this to obtain the reaction product nitrogen oxide. "The Eley-Rideal reaction takes place within a fraction of a second: the original kinetic energy of the nitrogen is conserved and you can therefore observe the reaction product rebounding from the surface at the same angle as which the original nitrogen atom collided with it." In the Langmuir-Hinshelwood reaction, however, there is no link between the direction of movement of the original atoms and the reaction products; due to the random walk across the surface the information about the original direction of movement is lost. Using detectors that can measure the direction of the reaction product, Zaharia and his team could unequivocally observe the fingerprint of the Eley-Rideal reaction.
The higher energy of the reaction products also revealed that an Eley-Rideal reaction had taken place: just one of the reacting atoms needs to break its attachment to the surface as a result of which less energy is needed. The Eley-Rideal reaction between heavier atoms is therefore attractive for applications in catalysis. The reaction pathway offers extra control over which particles react and that could lead to new ways of producing and processing materials. The research will be continued in a collaboration between DIFFER and the Center of Interface Dynamic for Sustainability that fellow researcher and former director of DIFFER Aart Kleyn has set up in the Chinese city of Chengdu.
Read more at: http://phys.org/news/2014-07-reaction-heavy-atoms-catalyst-surface.html#jCp
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