West Oxford Community Renewables is applying for a grant from “energyshare” to kick start a Micro-Hydro scheme on Osney Island, Oxford. We want to install a reverse Archimedes screw in the River Thames. We are hoping to win some of the £500,000 prize on offer to kick start our fund for an Archimedes screw in the Thames at Osney Lock. The projects which get the most on-line support by the end of June will get through to the next round.

If you would like to register your support then please follow this link:
http://www.energyshare.com/west-oxford-community-renewables

About our community
West Oxford is built around a river, but it’s a complicated relationship. We enjoy the power, beauty and history of the Thames every day. But we live on the front line when the waters rise. In the summer of 2007 we felt powerless as we watched the homes of friends and neighbours succumb to the flood waters.
Yet this community has always worked with the river, harnessed its great power. So now, here in the oldest industrial quarter of the city, we want to work with the river once again using the newest technology.

Our dream
To set up a microhydro system in the heart of Oxford that will use the power of the river to generate improvements for our community. Situated by Osney Lock, just across the river from the site of the city’s first electric power station, the benefits of the scheme will be two fold
1. Providing a source of green energy, a 48 kW installation could generate 159,169kWh a year, saving 68 tonnes of carbon dioxide each year.
2. Creating an income stream which can be invested in local community projects to help further reduce our community’s carbon footprint.

The story so far…..
A site has been identified and assessed as suitable. A full feasibility study has been completed to show that the project is both technically and financially viable. Flood risk analysis and ecology and arboricultural surveys have been carried out, to enable us to understand and manage any potential negative impact the project may have.
We are now working on leasing the land, securing planning permission and abstraction licence for the project.
We’re also working to secure the funding to carry out the project, through a community share scheme and loans.

About us
What started in 2007 as a group of enthusiastic neighbours around a kitchen table, is now a flourishing Industrial and Provident Society with a track record in setting up community owned renewable projects, with five installations complete and another three in the pipeline. The microhydro scheme will be our first hydrogeneration project.
We wouldn’t exist without the extraordinary community support we have received – not only from people living in the area, who have invested time and money in making our plans a reality, but also as a virtual community of friends, likeminded individuals and organisations who have supported us along the way.
We know that with your help, we can continue to flourish and play our part in making West Oxford the supportive and vibrant community we feel privileged to be a part of.
Together, we have the power to make it possible.

What do you think of when someone mentions the word laser? Music performances? Barcode scanners? Surgery? Communication? Weapons? Well, all of them would be correct and on April 7th, as part of the Frontiers of Science season, Dr Kate Lancaster gave a talk to a Science Oxford Live audience to tell us a bit more about the cutting edge research that happens not far from Oxford and that depends on some of the highest power lasers found around the globe. Dr Lancaster is a physicist and science communicator, with her research focused on laser-driven fusion energy, based at the Science and Technology Facilities Council (STFC) Rutherford Appleton Laboratory.

In a historical whistle-stop tour, Dr Lancaster recalled who was involved in the development of the laser. Although the device, the acronym standing for “light amplification by stimulated emission of radiation”, is governed by equations that were first derived by Einstein, he was too much of a theoretician to have been involved in the practical development which took place some decades later. First of all Townes and Schawlow discovered the MASER, a device in which coherent electromagnetic waves of the microwave frequency are produced using amplification by stimulated emission. By the late 1950s, many scientists were hoping to recreate the same effects with visible light (which is also a form of electromagnetic radiation, but of a shorter wavelength compared to microwaves) and Gould is widely credited with making the realisation that one could achieve this by using two mirrors to produce a narrow, coherent, intense beam of visible light of specific wavelength. Gould was also the first to coin the term LASER (light amplification by stimulated emission of radiation) for the phenomenon but in a twist of fate, he then spent 30 years fighting to be granted the patent for the technology, which was eventually granted to the Bell labs, where his competitors were based. Subsequently, Theodore Maiman was the one who developed the first laser prototype (the ruby laser), and further developments went on from there. Eventually, 10 Nobel prizes related to the development of the laser were awarded in the period between 1964 and 2009 (see table in Short history of laser development, J. Hecht, Optical Engineering, 2009 vol 49, page F99).

So, what are the key aspects of a laser? Dr Lancaster explained that one of the features of lasers is that they produce light which is highly coherent and monochromatic, meaning it is of a specific wavelength. This was demonstrated with a spectrometer (a device which measures the wavelength of the light that it detects) which showed that visible light created a widespread peak in the visible range of 400-650nm. Laser light, on the other hand, created a single sharp peak at a specific wavelength (532nm for a green laser, 630nm for a red laser). Secondly, laser light has very low divergence – if you shone a laser from the Earth to the moon, by the time it got there, the beam would be only a mile wide, which is pretty impressive given the distance. Finally, lasers are highly focusable into a single spot (based on the equation that intensity = power/area, meaning that the smaller the area the laser shines on, the higher the intensity).

Simplistically put, lasers work because photons are released as electrons change between different energy levels within an atom. Spontaneous emission involves an electron moving from a high energy to a low energy level accompanied by the release of a photon and stimulated absorption is the opposite of this process (an electron moves from low to high level whilst gobbling up the energy of a photon). If a photon, which has the energy equivalent to the difference between high and low energy states, comes along to an atom with an electron in a high energy state, it will stimulate the electron to fall into the lower level state, thereby emitting a photon. The emitted photon has the same energy as the original photon, leading to the emission of two waves with the same frequency which constructively interfere and so create a more intense wave. This is called stimulated emission and it is the main principle behind what happens in a laser. In a laser setup, the excitable electrons might be in neodymium atoms used to dope a glass block. This block is enclosed by reflective surfaces, which enable the signal to be amplified, and partial reduction in reflectivity allows this to signal to escape the cavity.

Since the discovery of lasers, there have been a number of new developments in terms of applications, ranging from CDs (1960s), laser cutting and barcode scanners (1970s), clinical applications such as laser surgery and communications using fibre optics (1980s). The improvements in lasers have involved the step-wise solving of a number of problems. Firstly, using Q switching, it was possible to release the laser only when fully saturated (i.e. all electrons are in a high level state), reducing background lasing. Another development was that of chirped pulse amplification (CPA), which uses refraction of the incident beam to temporarily lengthen and disperse the laser light so that its intensity does not damage the optical equipment (meaning that higher intensity can be achieved). These days scientists such as Dr Lancaster at the SFTC Vulcan facility are in the business of using the highest powered lasers to study processes such as fusion, and from her talk we got an impression of the excitement and enthusiasm she has for this field. It seems that at the moment, one of the limitations of fusion energy is the inability to fire the laser often enough – to run a fusion power station, it would be necessary to fire the laser four times every second, whereas it is currently only possible to fire such a powerful device once every half an hour or so. In addition, there is always the containment to think of because the high powered laser has to be located in a vacuum to avoid the laser making plasma of the air that it is surrounded by.

And what does the future hold in store? In biochemistry and structural biology, it may be possible to use small lasers as optical tweezers which would allow the pulling apart of protein and DNA single molecules to unfold them and study their function. Lasers will likely be part of quantum computers which could enable instant calculations to be performed that would render all current encryption algorithms useless, but at the same time create a potential for altogether new encryption methods. On a much larger scale, lasers may be useful in space-based telescope, because they could be effectively artificial star references. In conclusion, Dr Lancaster reckoned that currently the biggest challenge in the field is making a laser that is high powered enough and is able to fire with a high enough repetition rate – so plenty to look at for those currently in the field.

In summary, the talk was by an enthusiastic speaker on a fascinating subject. You can watch Dr Lancaster’s talk on the webcast via the Science Oxford Live website.

Some background:

Kate Lancaster’s website: http://sites.google.com/site/drkatelancaster/
Science & Technology Facilities Council: http://www.stfc.ac.uk/

‘The Atom’ at Science Oxford Live used the music of Bach played on a violin to illustrate atoms and energy. This seemed appropriate to me as know Bach means ‘small in Welsh’. Atoms are the smallest particle of a pure substance that can be told apart (classed as an element). The numbers, ratio and formation of even smaller entities such as, protons, neurons, electrons and quarks determine how the atoms will interact and combine with others to form molecules.

At this tiny scale, nothing stays still. Tiny particles are randomly moving and colliding, known as ‘Brownian motion’. This is faster in liquids than solids and faster still in gases, and increases with temperature.
Forces of attraction determine how atoms and molecules combine and the kind of structures they form, holding them together despite the Brownian motion. This in turn influences material properties, for example how hard, soft, brittle or rubbery we experience them to be.

Humans like to experiment with movements of atoms to create new substances and molecular structures. The large Hadron collider using magnetic force to accelerate and collide materials and is capable of generating completely new atoms, heavier than those seen in nature.

Nano technology has developed from systematically combining molecules in machine like assemblies, generating tiny structures, designed to move in a specific way or interact to serve a particular purpose, a bit like tiny gears and leavers. The cohesive forces and motion mean that substances used have be carefully selected and spread out into thin layers to elicit the desired behaviour.

Structures are built up, 2D and then 3D and combined. They can self assemble to form designed combinations where joints can be broken and remade (e.g sticky ends). This produces ‘shape shifters’ and ‘walkers’ with defined ways of generating their own motion, for example an extremely tiny ‘inch worm’ Ω.

Nano is a Greek word meaning, dwarf or very small. Just one millimetre is equivalent to one million nanometres. Professor Ned Seeman takes inspiration from Greek architecture creating these elaborate designs. DNA can be used as a nanoparticle, to build complex architectural structures (macromolecules) by manipulating the way strands combine.

Nanotechnology can be used for things such as incredibly tiny electronic circuitry in an IPOD, improved coatings to avoid rust, non stick surfaces and even in to improve interactions between skin and materials for example in sports training shoes and even ballet dancers pointe shoes, to protect from infection.
There is a lot of talk about the revolutionary potential of Nanotechnology. Should we worry? Very small particles can easily pass through bodies defences, get inside cells and interact with their natural machinery – great in terms of medicine and creams to nourish skin. Problems come if particles made for another reason are found to be harmful to people, wildlife and the environment and accidently escape or fall into the hands of someone wanting to cause harm.

This futuristic technology makes the ponderings of ancient Greeks philosophers more relevant than ever. When it comes to deciding whether to accept a technology, getting to grips to grips with classic fundamental questions like, ‘where is the boundary between our body and the world outside our body’, ‘what makes us who we are?’ and ‘how should we direct the things we make?’, is a very good place to start.

Soft Machines, Nanotechnology and Life Prof RAL Jones, http://www.softmachines.org/wordpress/

Prof Nadrain Seeman, http://seemanlab4.chem.nyu.edu/

Electrons, although closely studied by scientists, are often overlooked or held in contempt by the general public. At their peril, I might add. We all use batteries in our walkmans, i-pods, torches, mobile phones; in fact nearly all small mobile electronic devices have batteries. We happily change them when ‘empty’ for new ones and think nothing of handling them. Batteries are, of course, a store house of nearly free electrons, there for our pleasure to use as we please. We think little of taking safety precautions in their use.

But how many of us have been frightened to be caught out in a thunder storm or, even when indoors, hide under the blankets as the mighty crashes of thunder echo through the nightime? These are our same now ‘not-so-friendly’ electrons playing around in the skies enjoying, at last, to be truly free; indulging themselves in discharges of many thousands of amps; enough to strike you down dead, if they pass through your body on their journey to earth.

So what is the true nature of electrons? What are their secrets? Do they have a secret life and hidden identities?

The properties of nearly everything physicists, chemists and even biologists study are controlled by the electrons. Whether it be the colour, the magnetism, the conductivity, the way chemicals interact with one another to form new compounds, the nature of our DNA, or how our brains carry information. The list is endless.

Let us deal first with the type of electrons that provide electricity in our batteries or along the cables in our homes, including the electrons that take part in a bolt of lightning. These are known as FREE electrons. They are not confined in a solid or chemical such as sodium chloride (common salt) or silicon (a semiconductor) but are FREE to travel long distances along wires or to roam around in our i-pods. In this form electrons are small charged particles. They carry a small negative (minus) charge and are therefore attracted to a positive charge and using this property can made to move along a wire from one place to another. Or made to travel across empty space in a vacuum. They move from minus towards plus. The amount of charge or electricity that a single electron carries is miniscule; you need ten million, million, million of them for only one amp of electricity, just about enough electricity to run your TV set. Think how many there will be in a 5000 Amp bolt of lightning; the mind boggles!

Now let us think about electrons that are confined to a solid material. Remember that our whole universe is made up of ELECTRONS and their opposite number PROTONS that are positively charged and their neutral friends the NEUTRON!

Electrons in a solid are much more rigorously controlled than free electrons. They have to obey very complicated rules that may vary depending on the type of solid they are trapped inside. These rules are very very strict and control such things as how much energy they are allowed to have; how they are allowed, or not allowed, to move around; how they approach and interact with other electrons in the solid; where they are allowed to move to and which places in the solid are forbidden to them. A long list of complicated rules! And another thing; inside a solid no two electrons are allowed to be exactly the same. If two electrons have the same energy then they have to spin in opposite directions like mad dancers to differentiate one from the other. In spite of all the electrons in a solid being different from one another in some way it is important for them to interact with each other in defined ways to hold the solid together, say in the form of a crystal or a DNA molecule. So how can we describe the life of electrons inside a solid?

In the first instance we will think about a single atom of the element silicon. Silicon has fourteen electrons, each with a single negative charge; fourteen protons, each with a positive charge and fourteen friendly neutrons to add a bit of weight but with no charge. The protons and neutrons clump together at the centre of the atom, hugging each other and the electrons dance around them in rings. The first ring has only two electrons, the next ring has eight electrons and the outer ring has four electrons. Now remember all those strict rules I mentioned? This is the first of them, how many electrons are allowed in each ring. The next rule to think about is their energy. Remember electrons in solids must have different energies. The best picture to suggest to you is to think about country or old time dances. Ones with names like the ‘Dashing White Sergeant’, ‘The Veleta’ (an old time dance that is quite gentle and unenergetic), ‘Stripping The Willow’, The Circassian Circle, and Riverdance. Now you may not be familiar with all these dances; they are dances done in sets of four or eight and consist of a number of repeated movements; some slow and formal, other dances fast and energetic.

So think of the first two electrons in the silicon atom innermost circle. Think of these two electrons dancing the Veleta, slow and formal, constantly repeated and never allowed to stop. Now the next ring with eight electrons; let them dance The Stripping The Willow dance. A dance with a set of eight and more energetic than the Veleta and this ring of electrons must continue to dance this dance forever withoutpause. Finally the outermost ring; let them have some excitement and dance the Riverdance without ever thinking of stopping. This is the life of these electrons within this silicon atom.

But what happens when lots of silicon atoms come together to make a silicon crystal? The two innermost rings carry on their set dance but the outermost ring dancing the Riverdance gets a bit more freedom to move around atoms that are their neighbours in the crystal. In some way the dance becomes more chaotic as the atoms race around other atoms as well as part of their dance to hold the crystal together. Hence the dances are very formalised and follow strict rules.

Now the clumps of protons and neutrons hugging each other at the centre of each atom present a regular array of ‘stationary mounds’ in the crystal and may seem not to play much part other than as stationary onlookers and this is true. Most properties of solids are a result of the electrons BUT these stationary clumps do result in some important effects. If a dance with a particular energy is to be danced; the rules may specify a particular route around the crystal. Now if this route has to pass through points where clumps of protons and neutrons are sitting; then this dance CANNOT BE PERFORMED and this represents, and results in, a disallowed energy that cannot be used. This can result in an ENERGY GAP in the spectrum of electron energies. An important physical property, particularly for semiconductors.

These descriptions are a simplification and remember that I said that all electrons had to have different energies or if they have the same energy, then spin in opposite directions. All these strict rules are still true and must be obeyed. In solids like metals there are many, many electrons to cram in and to some extent outer electrons become almost free and can roam around more easily. Hence they conduct electricity to a much greater extent. Metals still have atoms and they also form crystals, the atoms arranging themselves in regular, predestined, arrays as do most solid elements that are not gases or liquids.

A further very important property of electrons in solids is they way that they can interact with light; visible light; infrared light, x-rays. In fact the whole of the ‘Electromagnetic spectrum’. Remember I said that the electron has a specific energy; now if the electron interacts with light it can change its energy. This is a very important property of electrons enabling them to change energy and jump to a different ring in the atom and commence a different dance. How do they do this?

If we think a little; there are many examples of solids interchanging energy with light, called electromagnetic radiation. My first example; think of your television set. Most receive their television programmes through their TV Ariel or satellite dish. How does this work? The electromagnetic wave of radio signal passes over your aerial or is focussed onto the black box at the centre of your satellite dish and the energy that the wave carries cause changes to the electrons in the solid of your dish or aerial. These are seen as small electric currents that are then amplified and converted to show the TV programme. A second example; light is absorbed by living plants. The energy that the light carries causes chemical changes in the plant that give it energy; termed photosynthesis. A final example that brings us close to conventional physics is the solar cell where light shining onto silicon pn junctions converts from light into electricity by energising electrons in the solid silicon.

A single particle of light, called a photon, can interact with an electron in a solid and change the energy of the electron. The electrons will then jump to another ring and commence a different dance designated for its new ring. This process is reversible and an electron in a solid may lose some of its energy and move to a different shell doing a different dance and at the same time emit a single particle of light called a photon. This is the mechanism by which light emitting diodes (LED’s) work.

These processes of interaction of electrons in solids with light are going on around us all the time, all over the universe. Scientists are continually investigating solids and the useful changes that can be brought about to give new materials or other useful effects such as new and novel interactions with laser light and the resulting effects on the electron energy or position in the crystal. A recent area of study has been nanomaterials. This simply means making materials of small dimensions containing only about one hundred atoms. If you pause and think for a moment of the effect of there being only one hundred atoms in a crystal you can realise that it will affect the way the electrons can dance around this small crystal. They are confined to a very small volume and this perturbs and effects their movement. The energy gap that I explained earlier is often affected by becoming a different size, shifting to a higher energy size. The way electricity is conducted through a very thin layer of solid only a few atoms thick will be different from the massive solid. These effects may make conduction easier of harder but will present new and novel properties that may be beneficial to mankind.

Imagine this situation: You are trying to interview someone who apparently has no recollection of a crime that they have committed. You have enough evidence to suggest that this person is ranked very high in the wanted list for this crime, but not enough to take to court, and you need some certain way of telling if it is a lie or the truth. You think about using a polygraph (the technical name for a lie detector machine) but you read somewhere that you can’t be sure that these are unreliable (61% accurate according to a survey of 421 Psychologists), and are easily tricked. Then you think about body language, and seeing if that would help with judging if the person is guilty, but you remember that it can be very easily controlled. You can’t think of anything else, so you continue with the interview, although a little exacerbated.

At certain times in the interview however, you seem to think that you may have noticed a slight twitch in the persons face, or some kind of fleeting expression, that was too quick for you to see what it was. The chances are, you may forget about this, or dismiss it as nervousness; however, in 1966 Haggard and Isaacs discovered that these fleeting expressions were ‘micro-expressions’ and were involuntary movements of facial or body muscles in response to thought processes by the brain, happening in around 1/15th to 1/25th of a second.

Firstly, let us examine why the old way of lie detection (a polygraph) isn’t as reliable as people thought. A polygraph is a machine that measures the blood pressure in the body, pulse, respiration and skin conductivity, which were all discovered to be symptoms of people telling a lie. However, these variables are far too susceptible from outside stimuli (if it is humid or dry, or if it is hot or cold, and if the air is thin or thick) and the power of the mind, which leads to its surprisingly low success rate.

Because of this unreliability, polygraphs shouldn’t be used as a way of prosecuting a criminal, only to give the detectives a slightly more than half chance of getting the right offender. This is why studying body language (more specifically micro-expressions) can be much more accurate, since they are governed by the subconscious. The problem arises when the psychologist giving the evidence in court is accused him or herself of lying by the prosecuted, since it depends on a psychologist’s judgment of the person, and it can be skewed towards either side of the case.

However, we shall delve into the legal implications of accusing someone on such evidence, and when it should or should not be used in conjunction with other techniques and hard evidence after looking at how someone is trained to recognize these micro-expressions. Anyone can learn the basics of micro-expressions, which is seeing them in the first place, but training someone to accurately discern what the expressions actually mean is another problem.

To combat this, a technique known as Micro-Expression Training Tool (or METT for short) was developed by a Professor Paul Ekman, which teaches the user to recognize these expressions in under an hour, and an METT advanced online tutorial, which when completed along with the final test will make you eligible for a certificate, provided that you have reached over 80% (over 95% and a certificate of expertise will be given).

There are ways however of training yourself without the cost of buying the METT. There are several websites which have a way of testing yourself on recognizing split second expressions, which are aimed not at getting you to see the micro-expressions, but to actually recognize which emotions are being expressed, usually some of the larger emotions, such as anger, happiness, disgust, surprise, contempt, etc. However, this way isn’t usually practical since in these tests, it is just two pictures, where one has a distinct version of the expression, and the other is normal, and it flicks once in about a millisecond; this is not ideal for accurate diagnosis of emotions in the subtleties of micro-expressions, but is an alternative to buying METT.

Further reading:
http://en.wikipedia.org/wiki/Microexpression
http://www.sciencedaily.com/releases/2006/05/060505161952.htm

‘Mind Change’

Baroness Susan Greenfield outlines the concept of ‘Mind Change’, which could be as significant as ‘Climate Change’ for the future of the human race, taking our brains to another dimension.

Mind Change describes the outcome of changes to the way our brains take in and process information becoming ‘hard wired’ as a result of prolific connection to digital technologies. This could have a profound effect on our thoughts, feelings, behaviour and relationships, ultimately affecting the cultural fabric of society.

Potential culprits are prolonged exposure to action packed sensory stimulation through computer games and bombardment with disjointed information from the internet, social networks and advertising. Neurological and psychological testing and informal reports indicate that on the one hand rapid decision making, co-ordination and performance on traditional IQ tests may improve. However, distracted attention resulting in shallow processing and reclusive individualistic behaviour with increased risk taking, could be a drawback.

Lady Greenfield acknowledges that effects visible in humans may be complex and subtle while technology develops so rapidly that scientific measures struggle to keep pace, creating uncertainty for legislators and policy makers. Nevertheless, she reasons we cannot afford to ignore the possibility that our thought patterns could change beyond recognition, with implications as serious as climate change in terms of human sustainability and longevity.

By telephone, Lady Greenfield discussed her ideas for a novel which have emerged during her lifetime researching neuroscience, pharmacology and the brain.

Describe your current interest?

One hundred years from now, we could be creating a society where cybernisation of the planet is the norm, especially as innovations like high definition TV become more and more vivid. This could have a profound effect on human consciousness, skills and relationships. While prolonged participation in activities such as computer games can improve skills like sensory motor co-ordination and response speed they may reduce concentration and empathy resulting in shallower information processing and dramatically different ‘mindsets’.

This might sound speculative because it is difficult to prove effects when you can’t control what people take in from screens day to day. Scientists can’t prove a negative and safely say it hasn’t had an effect. All they can do is look at trends. As brains attempt to keep up with proliferation of media in the environment we could be looking at an economy of attention.

How are our brains affected by information in the environment?

Minds are like a mobile phone network with cheaper calls for more frequently used numbers, numbers can become blocked or be forgotten if rarely used. This mechanism is called synaptic plasticity. This network is vulnerable to ‘lost and stolen’ processes, ‘hacking’ and ‘spam’.

How would you describe a ‘sensory’ and a ‘cognitive’ experience?

A sensory experience provides sights, sounds, smells, and movement, for example going to a disco or skiing. A cognitive experience involves reading a book, having a conversation, looking for meaning and narrative. People need a balance of both. Screen technology encourages a bias towards the sensory and can literally ‘blow your mind’.

Beyond receiving digital information from screens, what are the possible effects for developments such as Nanotechnology and Synthetic Biology?

Emerging technologies, such as body monitoring systems using nanotechnology challenge the notion of the body’s firewall with the outside world, eroding our sense of privacy which opens us up to third party intervention and scenarios such like ‘Brain Hacking’.

What would you say to those who might call you a scare monger?

This is only justified only if you know it is not a problem and it isn’t too complacent to suggest everything is just fine. I would prefer to be called a scare monger and be proved wrong than sleepwalk my way into a future where it is too late.

Mind change is a neutral term which doesn’t imply a good thing or a bad thing, it is simply a description of how we may evolve. In writing a novel I am aware it is a personal view, not a textbook, a little like ‘brave new world’. I allude to where the science is real and introduce people to democracy, concepts and possibilities, ideas and predictions that emanate from science and are interesting enough to read for pleasure.
“We need to think ahead, becoming the master not the servant of technology, defining what we want it to do, otherwise we are not serving the next generation well”.

How effective are current methods for studying brain activity?

Brain imaging acts like a ‘virtual photograph’. You can’t see the movement and the exposure is too slow. It is also invasive and expensive. Tests given to people in the imager are ‘blunt tools’ and there are many effects occurring in a person’s individual internal environment during the scanning process that are difficult to control and affect the result. It is still better than doing nothing. Studying mechanisms such as attention bias in addiction in a laboratory can inform brain scanning, indicating what to look for.

Scientists need to collaborate with web designers and educators to decide new things that could be done to develop software and focus the many possible tasks for studying cognition, attention, emotion and behaviour.

How are our brains affected by the way we interact with technology?

Our interaction with computers is an ongoing two sided dialogue. We design them to help us in learning e.g. developing cognitive processes such as driving. At the same time our brains adapt to this environment and our skill base changes becoming more machine like.

Simulations are very powerful e.g analysis of electrical signals in the brain which occur before a movement is initiated still happen in people who are paralysed. Tapping into this could further our intimate connection with technology for example, using it to control a robotic arm.

What do you think about techniques such as Neuro Linguistic Programming (NLP)?

Neural connectivity is the basis of how we come to see the world a different way, working with different problems. This can involve responses to words as well as actual things. Presentation can affect development of goods and services, influencing risk taking and leadership in the workforce.

How does ‘climate change relate to the concept of ‘mind change’?

Mind change and climate change are both critical scenarios concerning governments and negotiations between countries. There is sometimes an idea that science can save us through climate policy and eco products. An example of how quickly mind change can happen is the way that everyone now recognises the telephone. It may affect boys and girls differently according to the technologies they interact with and influence relations with developing countries. Time spent in virtual environments could lead to behaviour which is individualistic, reclusive, and child like with a high level of greed, impulsivity and disregard for consequences.

How can scientists and society at large tackle Mind Change?

Scientists need to anticipate and ‘see’ potential future impacts, considering economics and taking a multidisciplinary approach with dialogues transcending academic disciplines.
Regulation sometimes isn’t helpful and the processes happen too late. It can appear negative, stopping people from doing things. Instead it is better to be constructive, consulting people and giving them alternatives.

“We need to focus on, education, not regulation and work with the art of the possible. I would like to hear what parents and children think.”

We could devise a questionnaire to measure parents concerns and look for effects of age and gender, making observations and looking for consensus.

How would you define Progress?

“Enabling people to reach their full potential, which is now higher than ever before, using the best mixture of skills and talents.”

Having spoken to Baroness Greenfield the concept of ‘mind change’ is a great way to describe something that is already here, with individuals affected to a matter of degree. At a societal level there are already signs of a backlash from screen addiction. In the UK on trains and buses, casual observation suggests that books and newspapers are as popular as mobile phones and laptops. On the high street the stationary market appears to be booming while people are flocking to spas retreats, fleeing the countryside in droves at the weekend, weather permitting.

From my point of view, while the science remains uncertain, nourishing my brain is a top priority. This involves participating in activities, and discussion including both sensory and cognitive components. Making it acceptable to rely solely on technology for information could allow new embodied cultural divides to really set in. Given its elusive nature, here is a danger that the concept of Mind Change could disappear from our conscious awareness and fail to benefit from the attention it deserves, leaving us wide open to isolation and erosion of our autonomy and identity.

Continuing to allow machines to shape us could affect our ability to deeply engage with complex material and relate to others, essential attributes for collectively combating global climate change. Our minds are perhaps the most important tool we have in terms of conserving the planet, so it seems essential the two concepts are considered hand in hand.

More Information:
Baroness Greenfield: http://www.pharm.ox.ac.uk/research/greenfield

Each nation gets a blip and a flashing dot on the map whenever they detonate a nuclear weapon, with a running tally kept on the top and bottom bars of the screen. Hashimoto, who began the project in 2003, says that he created it with the goal of showing”the fear and folly of nuclear weapons.” It starts really slow — if you want to see real action, skip ahead to 1962 or so — but the buildup becomes overwhelming.

A team of scientists from Columbia University, Arizona State University, the University of Michigan, and the California Institute of Technology (Caltech) have programmed an autonomous molecular “robot” made out of DNA to start, move, turn, and stop while following a DNA track.

The development could ultimately lead to molecular systems that might one day be used for medical therapeutic devices and molecular-scale reconfigurable robots—robots made of many simple units that can reposition or even rebuild themselves to accomplish different tasks.

A paper describing the work appears in the current issue of the journal Nature.

The traditional view of a robot is that it is “a machine that senses its environment, makes a decision, and then does something—it acts,” says Erik Winfree, associate professor of computer science, computation and neural systems, and bioengineering at Caltech.

Milan N. Stojanovic, a faculty member in the Division of Experimental Therapeutics at Columbia University, led the project and teamed up with Winfree and Hao Yan, professor of chemistry and biochemistry at Arizona State University and an expert in DNA nanotechnology, and with Nils G. Walter, professor of chemistry and director of the Single Molecule Analysis in Real-Time (SMART) Center at the University of Michigan in Ann Arbor, for what became a modern-day self-assembly of like-minded scientists with the complementary areas of expertise needed to tackle a tough problem.

Shrinking robots down to the molecular scale would provide, for molecular processes, the same kinds of benefits that classical robotics and automation provide at the macroscopic scale. Molecular robots, in theory, could be programmed to sense their environment (say, the presence of disease markers on a cell), make a decision (that the cell is cancerous and needs to be neutralized), and act on that decision (deliver a cargo of cancer-killing drugs).

Or, like the robots in a modern-day factory, they could be programmed to assemble complex molecular products. The power of robotics lies in the fact that once programmed, the robots can carry out their tasks autonomously, without further human intervention.

With that promise, however, comes a practical problem: how do you program a molecule to perform complex behaviors?

“In normal robotics, the robot itself contains the knowledge about the commands, but with individual molecules, you can’t store that amount of information, so the idea instead is to store information on the commands on the outside,” says Walter. And you do that, says Stojanovic, “by imbuing the molecule’s environment with informational cues.”

“We were able to create such a programmed or ‘prescribed’ environment using DNA origami,” explains Yan. DNA origami, an invention by Caltech Senior Research Associate Paul W. K. Rothemund, is a type of self-assembled structure made from DNA that can be programmed to form nearly limitless shapes and patterns (such as smiley faces or maps of the Western Hemisphere or even electrical diagrams). Exploiting the sequence-recognition properties of DNA base pairing, DNA origami are created from a long single strand of DNA and a mixture of different short synthetic DNA strands that bind to and “staple” the long DNA into the desired shape. The origami used in the Nature study was a rectangle that was 2 nanometers (nm) thick and roughly 100 nm on each side.

The researchers constructed a trail of molecular “bread crumbs” on the DNA origami track by stringing additional single-stranded DNA molecules, or oligonucleotides, off the ends of the staples. These represent the cues that tell the molecular robots what to do—start, walk, turn left, turn right, or stop, for example—akin to the commands given to traditional robots.

The molecular robot the researchers chose to use—dubbed a “spider”—was invented by Stojanovic several years ago, at which time it was shown to be capable of extended, but undirected, random walks on two-dimensional surfaces, eating through a field of bread crumbs.

To build the 4-nm-diameter molecular robot, the researchers started with a common protein called streptavidin, which has four symmetrically placed binding pockets for a chemical moiety called biotin. Each robot leg is a short biotin-labeled strand of DNA, “so this way we can bind up to four legs to the body of our robot,” Walter says. “It’s a four-legged spider,” quips Stojanovic. Three of the legs are made of enzymatic DNA, which is DNA that binds to and cuts a particular sequence of DNA. The spider also is outfitted with a “start strand”—the fourth leg—that tethers the spider to the start site (one particular oligonucleotide on the DNA origami track). “After the robot is released from its start site by a trigger strand, it follows the track by binding to and then cutting the DNA strands extending off of the staple strands on the molecular track,” Stojanovic explains.

“Once it cleaves,” adds Yan, “the product will dissociate, and the leg will start searching for the next substrate.” In this way, the spider is guided down the path laid out by the researchers. Finally, explains Yan, “the robot stops when it encounters a patch of DNA that it can bind to but that it cannot cut,” which acts as a sort of flypaper.

Although other DNA walkers have been developed before, they’ve never ventured farther than about three steps. “This one,” says Yan, “can walk up to about 100 nanometers. That’s roughly 50 steps.”

“This in itself wasn’t a surprise,” adds Winfree, “since Milan’s original work suggested that spiders can take hundreds if not thousands of processive steps. What’s exciting here is that not only can we directly confirm the spiders’ multistep movement, but we can direct the spiders to follow a specific path, and they do it all by themselves—autonomously.”

In fact, using atomic force microscopy and single-molecule fluorescence microscopy, the researchers were able to watch directly spiders crawling over the origami, showing that they were able to guide their molecular robots to follow four different paths.

“Monitoring this at a single molecule level is very challenging,” says Walter. “This is why we have an interdisciplinary, multi-institute operation. We have people constructing the spider, characterizing the basic spider. We have the capability to assemble the track, and analyze the system with single-molecule imaging. That’s the technical challenge.” The scientific challenges for the future, Yan says, “are how to make the spider walk faster and how to make it more programmable, so it can follow many commands on the track and make more decisions, implementing logical behavior.”

“In the current system,” says Stojanovic, “interactions are restricted to the walker and the environment. Our next step is to add a second walker, so the walkers can communicate with each other directly and via the environment. The spiders will work together to accomplish a goal.” Adds Winfree, “The key is how to learn to program higher-level behaviors through lower-level interactions.”

Such collaboration ultimately could be the basis for developing molecular-scale reconfigurable robots—complicated machines that are made of many simple units that can reorganize themselves into any shape—to accomplish different tasks, or fix themselves if they break. For example, it may be possible to use the robots for medical applications. “The idea is to have molecular robots build a structure or repair damaged tissues,” says Stojanovic.

“You could imagine the spider carrying a drug and bonding to a two-dimensional surface like a cell membrane, finding the receptors and, depending on the local environment,” adds Yan, “triggering the activation of this drug.”

Such applications, while intriguing, are decades or more away. “This may be 100 years in the future,” Stojanovic says. “We’re so far from that right now.”

“But,” Walter adds, “just as researchers self-assemble today to solve a tough problem, molecular nanorobots may do so in the future.”

The other coauthors on the paper, “Molecular robots guided by prescriptive landscapes,” are Kyle Lund and Jeanette Nangreave from Arizona State University; Anthony J. Manzo, Alexander Johnson-Buck, and Nicole Michelotti from the University of Michigan; Nadine Dabby from Caltech; and Steven Taylor and Renjun Pei from Columbia University. The work was supported by the National Science Foundation, the Army Research Office, the Office of Naval Research, the National Institutes of Health, the Department of Energy, the Searle Foundation, the Lymphoma and Leukemia Society, the Juvenile Diabetes Research Foundation, and a Sloan Research Fellowship.

Contact: Kathy Svitil ksvitil@caltech.edu

Image Credit: Courtesy of Paul Michelotti

Physicists at McGill University have developed a system for measuring the energy involved in adding electrons to semi-conductor nanocrystals, also known as quantum dots – a technology that may revolutionize computing and other areas of science. Dr. Peter Grütter, McGill’s Associate Dean of Research and Graduate Education, Faculty of Science, explains that his research team has developed a cantilever force sensor that enables individual electrons to be removed and added to a quantum dot and the energy involved in the operation to be measured.

Being able to measure the energy at such infinitesimal levels is an important step in being able to develop an eventual replacement for the silicon chip in computers – the next generation of computing. Computers currently work with processors that contain transistors that are either in an on or off position – conductors and semi-conductors – while quantum computing would allow processors to work with multiple states, vastly increasing their speed while reducing their size even more.

Although the term “quantum leap” is used in everyday language to connote something very large, the word “quantum” itself actually means the smallest amount by which certain physical quantities can change. Knowledge of these energy levels enables scientists to understand and predict the electronic properties of the nanoscale systems they are developing.

“We are determining optical and electronic transport properties,” Grütter said. “This is essential for the development of components that might replace silicon chips in current computers.”

The electronic principles of nanosystems also determine their chemical properties, so the team’s research is relevant to making chemical processes “greener” and more energy efficient. For example, this technology could be applied to lighting systems, by using nanoparticles to improving their energy efficiency. “We expect this method to have many important applications in fundamental as well as applied research,” said Lynda Cockins of McGill’s Department of Physics.

The principle of the cantilever sensor sounds relatively simple. “The cantilever is about 0.5 mm in size (about the thickness of a thumbnail) and is essentially a simple driven, damped harmonic oscillator, mathematically equivalent to a child’s swing being pushed,” Grütter explained. “The signal we measure is the damping of the cantilever, the equivalent to how hard I have to push the kid on the swing so that she maintains a constant height, or what I would call the ‘oscillation amplitude.’ ”

Dr. Yoichi Miyahara, Aashish Clerk and Steven D. Bennett of McGill’s Dept. of Physics, and scientists at the Institute for Microstructural Sciences of the National Research Council of Canada contributed to this research, which was published online late yesterday afternoon in the Proceedings of the National Academy of Sciences. The research received funding from the Natural Sciences and Engineering Research Council of Canada, le Fonds Québécois de le Recherche sur la Nature et les Technologies, the Carl Reinhardt Fellowship, and the Canadian Institute for Advanced Research.

This image shows the electrostatic energy given off when electrons are added to a quantum dot. It was created with an atomic-force microscope. Photo Credit: Dept. of Physics, McGill University.

PETMAN
“PETMAN is an anthropomorphic robot for testing chemical protection clothing used by the US Army. Unlike previous suit testers, which had to be supported mechanically and had a limited repertoire of motion, PETMAN will balance itself and move freely; walking, crawling and doing a variety of suit-stressing calisthenics during exposure to chemical warfare agents. PETMAN will also simulate human physiology within the protective suit by controlling temperature, humidity and sweating when necessary, all to provide realistic test conditions.”

Find out more about PETMAN here.

RiSE: The Amazing Climbing Robot.
“RiSE is a robot that climbs vertical terrain such as walls, trees and fences. RiSE uses feet with micro-claws to climb on textured surfaces. RiSE changes posture to conform to the curvature of the climbing surface and its tail helps RiSE balance on steep ascents.”

Find out more about RiSE here.

BigDog: The Most Advanced Rough-Terrain Robot on Earth
“BigDog is the alpha male of the Boston Dynamics robots. It is a rough-terrain robot that walks, runs, climbs and carries heavy loads. BigDog is powered by an engine that drives a hydraulic actuation system. BigDog has four legs that are articulated like an animal’s, with compliant elements to absorb shock and recycle energy from one step to the next. BigDog is the size of a large dog or small mule; about 3 feet long, 2.5 feet tall and weighs 240 lbs.”

Find out more about BigDog here.

Visit the Boston Dynamics website here.

Shooting lasers at the sky can make the germ of a raincloud, a new study shows. In an experiment that smacks of science fiction, scientists used a high-powered laser to squeeze water from air, both indoors and out.

Although the technique is unlikely to be an instant rainmaker anytime soon, it could plant the seeds for more eco-friendly cloud manipulation.

“This is the first time that a laser was used to condense water from both laboratory experiments and from the atmosphere,” says Jérôme Kasparian of the University of Geneva, a coauthor of the study. The work appeared in the May 2 Nature Photonics.

Atmospheric scientists have been trying to build artificial clouds since the 1940s, with mixed success. The most popular method, shooting particles of silver iodide into the sky, relied on the fact that raindrops need something to condense around.

“It’s just like when you take a shower with hot water — it’s very humid in your bathroom, but it’s not raining,” Kasparian says. Water droplets need a surface to condense on, like a mirror in a bathroom or a speck of dust or pollen in the atmosphere.

Previous experimenters hoped droplets would form around flakes of silver, salt or other materials just like on a bathroom mirror. “The idea is, you provide more condensation nuclei, you get more condensation,” Kasparian says. “It seems obvious, but in practice no one could really prove that it works.”

Kasparian and colleagues took inspiration from a mist-making apparatus that was invented in 1911 to detect cosmic rays, highly energetic subatomic particles that come from deep space. A physicist named Charles Wilson noticed that when cosmic rays strike a sealed container filled with water vapor, they leave a visible trail of water droplets behind them. This works because the cosmic rays knock electrons off the water molecules, leaving behind charged particles that act like specks of dust for water to congeal around.

“Our idea was to mimic what happens in a Wilson chamber,” Kasparian says. “If you get some condensation with cosmic rays, we should get even more condensation with a laser.”

Kasparian and his colleagues tested this idea by shooting a high-powered infrared laser into a cloud chamber. The laser shot extremely short pulses of intense light, which each carrying several terawatts — or a trillion watts — of energy.

The view fogged up immediately. Droplets about 50 micrometers in diameter formed first, and grew to about 80 micrometers in diameter over the next three seconds. “The effect in the cloud chamber was very spectacular and visible by bare eye,” Kasparian says. “We expected an effect, definitely. But that magnitude was pretty much a surprise.”

Next, the researchers took the laser out in the backyard to try it on the sky. They rolled the laser, called “Teramobile” for its terawatt power and its mobility, onto the lawn behind the physics building at the Free University of Berlin on several nights in the fall of 2008. The clouds, if they formed, would be too distant to see with the naked eye, so the team used a second laser to confirm the cloudy view.

“It also worked quite well in the free atmosphere,” Kasparian says. “That was quite surprising, and a very good surprise.”

Kasparian thinks lasers could provide a more reliable and environmentally friendly way to build clouds. “If you can seed clouds and get some control or at least modulation on the weather, the implications are huge for agriculture, many other economic sectors, many aspects of human life,” Kasparian says. “There are potentially huge consequences.”

“It is a clever technique,” says John Latham of the National Center for Atmospheric Research in Boulder, Colo. But he’s skeptical that laser-built clouds could actually make it rain on demand. “Rainfall production requires many conditions to be met,” he cautions.

Image Credit: Jean-Pierre Wolf / University of Geneva

A recent advance by Arizona State University researchers in developing nanowires could lead to more efficient photovoltaic cells for generating energy from sunlight, and to better light-emitting diodes (LEDs) that could replace less energy-efficient incandescent light bulbs.

Electrical engineers Cun-Zheng Ning and Alian Pan are working to improve quaternary alloy semiconductor nanowire materials.

Nanowires are tens of nanometres in diameter and tens of microns in length. Quaternary alloys are made of semiconductors with four elements, often made by alloying two or more compound semiconductors.

Semiconductors are the material basis for technologies such as solar cells, high-efficiency LEDs for lighting, and for visible and infrared detectors.

One of the most critical parameters of semiconductors that determine the feasibility for these technologies is the band gap. The band gap of a semiconductor determines, for example, if a given wavelength of sun light is absorbed or left unchanged by the semiconductor in a solar cell.

Band gap also determines what colour of light an LED emits. To make solar cells more efficient, it’s necessary to increase the range of band gaps.

Ideally, the highest solar cell efficiency is achieved by having a wide range of band gaps that matches the entire solar spectrum, explains Ning, a professor in the School of Electrical, Computer and Energy Engineering, a part of ASU’s Ira A. Fulton Schools of Engineering.

In LED lighting applications, he says, more available band gaps means more colours can be emitted, providing more flexibility in colour engineering or colour rendering of light.

For example, different proportions of red, green and blue colours would mix with different white colours. More flexibility would allow white colour to be adjusted to suit various situations, or individual preferences.

Similarly, Ning says, detection of different colours requires semiconductors of different band gaps. The more band gaps that are available, the more information can be acquired about an object to be detected. Thus, all of these lighting applications can be improved by having semiconductors with a wide range of band gaps.

The researchers say the hurdle is that every manmade or naturally occurring semiconductor has only a specific band gap.

One standard way to broaden the range of band gaps is to alloy two or more semiconductors. By adjusting the relative proportion of two semiconductors in an alloy, it’s possible to develop new band gaps between those of the two semiconductors.

But accomplishing this requires a condition called lattice constant matching, which requires similar inter-atomic spaces between two semiconductors to be grown together.

‘This is why we cannot grow alloys of arbitrary compositions to achieve arbitrary band gaps,’ Ning says. ‘This lack of available band gaps is one of reasons current solar cell efficiency is low, and why we do not have LED lighting colours that can be adjusted for various situations.’

In recent attempts to grow semiconductor nanowires with ‘almost’ arbitrary band gaps, the research team led by Ning and Pan, an assistant research professor, have used a new approach to produce an extremely wide range of band gaps.

They alloyed two semiconductors, zinc sulphide (ZnS) and cadmium selenide (CdSe) to produce the quaternary semiconductor alloy ZnCdSSe, which produced continuously varying compositions of elements on a single substrate (a material on which a circuit is formed or fabricated).

Ning says this the first time a quaternary semiconductor has been produced in the form of a nanowire or nanoparticle.

By controlling the spatial variation of various elements and the temperature of a substrate (called the dual-gradient method), the team produced light emissions that ranged from 350 to 720 nanometres on a single substrate only a few centimetres in size.

The colour spread across the substrate can be controlled to a large degree, and Ning says he believes this dual-gradient method can be more generally applied to produce other alloy semiconductors or expand the band gap range of these alloys.

To explore the use of quaternary alloy materials for making photovoltaic cells more efficient, his team has developed a lateral multi-cell design combined with a dispersive concentrator.

The concept of dispersive concentration, or spectral split concentration, has been explored for decades. But the typical application uses a separate solar cell for each wavelength band.

With the new materials, Ning hopes to build a monolithic lateral super-cell that contains multiple subcells in parallel, each optimised for a given wavelength band. The multiple subcells can absorb the entire solar spectrum. Such solar cells will be able to achieve extremely high efficiency with low fabrication cost. The team is working on both the design and fabrication of such solar cells.

Similarly, the new quaternary alloy nanowires with large wavelength span can be explored for colour-engineered light applications.

The researchers have demonstrated that colour control through alloy composition control can be extended to two spatial dimensions, a step closer to colour design for direct white light generation or for colour displays.

A California Institute of Technology (Caltech)-led team of researchers and clinicians has published the first proof that a targeted nanoparticle – used as an experimental therapeutic and injected directly into a patient’s bloodstream – can traffic into tumours, deliver double-stranded small interfering RNAs (siRNAs), and turn off an important cancer gene using a mechanism known as RNA interference (RNAi). Moreover, the team provided the first demonstration that this new type of therapy, infused into the bloodstream, can make its way to human tumours in a dose-dependent fashion – i.e., a higher number of nanoparticles sent into the body leads to a higher number of nanoparticles in the tumour cells.

These results, published in the March 21 advance online edition of the journal Nature, demonstrate the feasibility of using both nanoparticles and RNAi-based therapeutics in patients, and open the door for future ‘game-changing’ therapeutics that attack cancer and other diseases at the genetic level, says Mark Davis, the Warren and Katharine Schlinger Professor of Chemical Engineering at Caltech, and the research team’s leader.

The discovery of RNA interference, the mechanism by which double strands of RNA silence genes, won researchers Andrew Fire and Craig Mello the 2006 Nobel Prize in Physiology or Medicine. The scientists first reported finding this novel mechanism in worms in a 1998 Nature paper. Since then, the potential for this type of gene inhibition to lead to new therapies for diseases like cancer has been highly touted.

‘RNAi is a new way to stop the production of proteins,’ says Davis. What makes it such a potentially powerful tool, he adds, is the fact that its target is not a protein. The vulnerable areas of a protein may be hidden within its three-dimensional folds, making it difficult for many therapeutics to reach them. In contrast, RNA interference targets the messenger RNA (mRNA) that encodes the information needed to make a protein in the first place.

‘In principle,’ says Davis, ‘that means every protein now is druggable because its inhibition is accomplished by destroying the mRNA. And we can go after mRNAs in a very designed way given all the genomic data that are and will become available.’

Still, there have been numerous potential roadblocks to the application of RNAi technology as therapy in humans. One of the most problematic has been finding a way to ferry the therapeutics, which are made up of fragile siRNAs, into tumour cells after direct injection into the bloodstream. Davis, however, had a solution. Even before the discovery of RNAi, he and his team had begun working on ways to deliver nucleic acids into cells via systemic administration. They eventually created a four-component system – featuring a unique polymer – that can self-assemble into a targeted, siRNA-containing nanoparticle. The siRNA delivery system is under clinical development by Calando Pharmaceuticals, Inc., a Pasadena-based nanobiotech company.

‘These nanoparticles are able to take the siRNAs to the targeted site within the body,’ says Davis. Once they reach their target – in this case, the cancer cells within tumours – the nanoparticles enter the cells and release the siRNAs.

The scientific results described in the Nature paper are from a Phase I clinical trial of these nanoparticles that began treating patients in May 2008. Phase I trials are, by definition, safety trials; the idea is to see if and at what level the drug or other therapy turns harmful or toxic. These trials can also provide an in-human scientific proof of concept – which is exactly what is being reported in the Nature paper.

Using a new technique developed at Caltech, the team was able to detect and image nanoparticles inside cells biopsied from the tumours of several of the trial’s participants. In addition, Davis and his colleagues were able to show that the higher the nanoparticle dose administered to the patient, the higher the number of particles found inside the tumour cells – the first example of this kind of dose-dependent response using targeted nanoparticles.

Even better, Davis says, the evidence showed the siRNAs had done their job. In the tumour cells analysed by the researchers, the mRNA encoding the cell-growth protein ribonucleotide reductase had been degraded. This degradation, in turn, led to a loss of the protein.

More to the point, the mRNA fragments found were exactly the length and sequence they should be if they’d been cleaved in the spot targeted by the siRNA, notes Davis. ‘It’s the first time anyone has found an RNA fragment from a patient’s cells showing the mRNA was cut at exactly the right base via the RNAi mechanism,’ he says. ‘It proves that the RNAi mechanism can happen using siRNA in a human.’

‘There are many cancer targets that can be efficiently blocked in the laboratory using siRNA, but blocking them in the clinic has been elusive,’ says Antoni Ribas, associate professor of medicine and surgery at UCLA’s Jonsson Comprehensive Cancer Centre. ‘This is because many of these targets are not amenable to be blocked by traditionally designed anti-cancer drugs. This research provides the first evidence that what works in the lab could help patients in the future by the specific delivery of siRNA using targeted nanoparticles. We can start thinking about targeting the untargetable.’

‘Although these data are very early and more research is needed, this is a promising study of a novel cancer agent, and we are proud of our contribution to the initial clinical development of siRNA for the treatment of cancer,’ says Anthony Tolcher, director of clinical research at South Texas Accelerated Research Therapeutics (START).

‘Promising data from the clinical trials validates our years of research at City of Hope into ribonucleotide reductase as a target for novel gene-based therapies for cancer,’ adds coauthor Yun Yen, associate director for translational research at City of Hope. ‘We are seeing for the first time the utility of siRNA as a cancer therapy and how nanotechnology can target cancer cells specifically.’

The Phase I trial – sponsored by Calando Pharmaceuticals – is proceeding at START and UCLA’s Jonsson Comprehensive Cancer Centre, and the clinical results of the trial will be presented at a later time. ‘At the very least, we’ve proven that the RNAi mechanism can be used in humans for therapy and that the targeted delivery of siRNA allows for systemic administration,’ Davis says. ‘It is a very exciting time.’

Re­search­ers are re­port­ing that they have passed a ma­jor hur­dle in the quest to cre­ate a radic­ally new kind of com­put­er, the quan­tum com­put­er.

Quan­tum com­put­ers would ex­ploit the some­times ap­par­ently non­sen­si­cal laws of quan­tum phys­ics, or na­ture at the sub­a­tom­ic scale, to achieve un­prec­e­dent­ed pow­er and speed.

A ma­jor chal­lenge been find­ing a way to ma­ni­pu­late in­di­vid­ual elec­trons, elec­tric­ally charged com­po­nents of atoms. Elec­trons are seen as the most likely can­di­dates to con­sti­tute the new machi­nes’ pro­cess­ing com­po­nents, or “qu­bits.”

Prince­ton phys­i­cist Ja­son Pet­ta said he and some col­leagues have dem­on­strat­ed a meth­od that al­ters the prop­er­ties of a lone elec­tron with­out dis­turb­ing the tril­lions of elec­trons in its im­me­di­ate sur­round­ings. The feat is con­sid­ered es­sen­tial to the de­vel­op­ment of quan­tum com­put­ers.

Petta has fash­ioned a new meth­od of trap­ping one or two elec­trons in mi­cro­scop­ic cor­rals cre­ated by ap­ply­ing to mi­nus­cule elec­trodes volt­ages, or elec­tric fields that move elec­trons. Writ­ing in the Feb. 5 edi­tion of the re­search jour­nal Sci­ence, Pet­ta and col­leagues de­scribe how elec­trons trapped in these cor­rals form “spin qu­bits,” quan­tum ver­sions of clas­sic com­put­er in­forma­t­ion un­its known as bits.

Pre­vi­ous ex­pe­ri­ments used a tech­nique in which elec­trons were ex­posed to mi­cro­wave radia­t­ion. How­ev­er, be­cause it af­fect­ed all the elec­trons un­iformly, the tech­nique could not be used to ma­ni­pu­late sin­gle elec­trons in spin qu­bits. It al­so was slow. Pet­ta’s meth­od not only achieves con­trol of sin­gle elec­trons, but it does so ex­tremely rap­id­ly, he said—in a bil­lionth of a sec­ond.

Sub­a­tom­ic par­t­i­cles are found to fol­low the laws of quan­tum phys­ics—in which, for ex­am­ple, they can be in two places at once—as long as these par­t­i­cles stay alone or in very small groups. When they come into con­tact with a great­er mass, the quan­tum ef­fects norm­ally ap­pear to van­ish.

“If you can take a small enough ob­ject like a sin­gle elec­tron and iso­late it well enough from ex­ter­nal per­turba­t­ions, then it will be­have quan­tum me­chan­ic­ally for a long pe­ri­od of time,” said Pet­ta. “All we want is for the elec­tron to just sit there and do what we tell it to do. But the out­side world is sort of pok­ing at it, and that pro­cess of the out­side world pok­ing at it causes it to lose its quan­tum me­chan­ical na­ture.”

When the elec­trons in Pet­ta’s ex­pe­ri­ment are in what he calls their quan­tum state, they are “co­her­en­t,” fol­lowing rules that are radic­ally dif­fer­ent from the world seen by the na­ked eye. Liv­ing for frac­tions of a sec­ond in the realm of quan­tum phys­ics be­fore they are rat­tled by ex­ter­nal forc­es, the elec­trons obey a un­ique set of phys­i­cal laws that gov­ern the be­hav­ior of ultra-small ob­jects. Quan­tum com­put­ers would be de­signed to take ad­van­tage of these char­ac­ter­is­tics.

In ad­di­tion to elec­trical charge, elec­trons pos­sess some­thing akin to rota­t­ion. In the quan­tum world, ob­jects can turn in ways that are at odds with com­mon ex­perience. The Aus­tri­an the­o­ret­i­cal phys­i­cist Wolf­gang Pau­li, who won the No­bel Prize in Phys­ics in 1945, pro­posed that an elec­tron in a quan­tum state can as­sume one of two states, “spin-up” or “spin-down.” It can be im­ag­ined as be­hav­ing like a ti­ny ba­r mag­net with spin-up cor­re­spond­ing to the north pole point­ing up and spin-down cor­re­spond­ing to the north pole point­ing down.

An elec­tron in a quan­tum state can sim­ul­ta­ne­ous­ly be par­tially in the spin-up state and par­tially in the spin-down state or any­where in be­tween, a quan­tum me­chan­ical prop­er­ty called “su­per­po­si­tion of states.” A qu­bit based on the spin of an elec­tron could have nearly lim­it­less po­ten­tial be­cause it can be nei­ther strictly on nor strictly off.

New de­signs could take ad­van­tage of a rich set of pos­si­bil­i­ties of­fered by har­ness­ing this prop­er­ty to en­hance com­put­ing pow­er. In the past dec­ade, the­o­rists and math­e­mati­cians have de­signed for­mu­las that ex­ploit this mys­te­ri­ous su­per­po­si­tion to per­form in­tri­cate cal­cula­t­ions at speeds un­matched by supercom­put­ers to­day.

Pet­ta’s work is aimed at ex­ploiting elec­tron spin.

“In the quest to build a quan­tum com­put­er with elec­tron spin qu­bits, nu­clear spins are typ­ic­ally a nui­sance,” said Gui­do Burk­ard, a the­o­ret­i­cal phys­i­cist at the Uni­vers­ity of Kon­stanz in Germany. “Petta and cowork­ers dem­on­strate a new meth­od that uti­lizes the nu­clear spins for per­forming fast quan­tum opera­t­ions. For sol­id-state quan­tum com­put­ing, their re­sult is a big step for­ward.”

Pet­ta’s spin qubits, which he en­vi­sions as the co­re of fu­ture quan­tum log­ic el­e­ments, are cooled to ultra-cold tem­per­a­tures and trapped in two ti­ny cor­rals known as quan­tum wells on the sur­face of a chip made of high-pur­ity gal­li­um ar­se­nide. The depth of each well is con­trolled by var­y­ing the volt­age on ti­ny elec­trodes or gates. Like a jug­gler toss­ing two balls be­tween his hands, Petta can move the elec­trons from one well to the oth­er by se­lec­tively switch­ing the gate volt­ages.

Be­fore this ex­pe­ri­ment, it was­n’t clear how ex­pe­ri­menters could ma­ni­pu­late the spin of one elec­tron with­out dis­turb­ing the spin of anoth­er in a closely packed space, ac­cord­ing to phys­i­cist Phuan Ong, di­rec­tor of the Prince­ton Cen­ter for Com­plex Ma­te­ri­als.

Pet­ta’s re­search al­so is part of the fledg­ling field of “spin­tron­ics” in which sci­en­tists are stu­dy­ing how to use an elec­tron’s spin to cre­ate new types of elec­tronic de­vices. Most elec­trical de­vices to­day op­er­ate on the ba­sis of anoth­er key prop­er­ty of the elec­tron, its charge.

There are many more chal­lenges to face, Pet­ta said. “Our ap­proach is really to look at the build­ing blocks of the sys­tem, to think deeply about what the lim­ita­t­ions are and what we can do to over­come them,” he added. “But we are still at the lev­el of just ma­ni­pu­lat­ing one or two quan­tum bits, and you really need hun­dreds to do some­thing use­ful.” As ex­cit­ed as he is about pre­s­ent prog­ress, long-term ap­plica­t­ions are still years away, he added; “it’s a one-day-at-a-time ap­proach.”

An Oxford University study says the best way to reduce emissions in the short term is a ‘drastic downscaling of both size and weight’ of conventional petrol and diesel cars.

The research by Smith School of Enterprise and the Environment suggests that we should not rely on manufacturers producing hydrogen or battery-powered vehicles in the next decade.

The report ‘Future of Mobility Roadmap’ assesses the potential for low carbon transport on land, by air and sea. It finds that electric and hydrogen vehicles are likely to remain niche products for many years because of limited battery life and the high cost of platinum, which is needed for the catalysts in hydrogen fuelled cars.

The study editor Sir David King and lead author Dr Oliver Inderwildi urge the government to impose higher taxes on drivers of large, inefficient vehicles and reinvest the money in better public transport and measures to get more people cycling and walking.

Dr Inderwildi says: ‘There is ample opportunity for emissions reductions by further improvements of currently available technology combined with a change in user habits.’

Rather than rely on the manufacturers to provide the ‘silver bullet’ solution to cut transport emissions, the report recommends behavioural change, urging consumers to influence manufacturers through their buying power. Manufacturers are more likely to produce smaller vehicles if customers opt not to buy larger, heavier vehicles with higher carbon emissions.

Better technology could significantly cut emissions from aircraft and shipping but incentives and regulation will be needed to encourage users to switch to low-carbon forms of transport, says the report.

It highlights algae-based biofuels as a means of significantly cutting transport emissions in the future and points out the limitations of biofuels as an alternative because of land shortages and food security concerns. First generation biofuels, derived from food stocks, ‘have proved the viability of such fuels, but remain a local solution, as in Brazil,’ it says.

Dr Inderwildi sees electric and diesel rail systems as the way forward in bringing down transport emissions but says there are disadvantages in the resulting infrastructure costs and lack of flexibility in route planning. Even so, reducing the carbon footprint of cars and replacing domestic flights with high speed rail could still produce ‘drastic emissions savings’.

The study warns that action must be taken immediately to have any impact on climate change because of the long lifetime of transport fleets and subsequent delays in technological impact.

‘Many technological options are already available and, in combination with infrastructure investments, [will] support the economy, reduce greenhouse gas emissions and provide other long-term benefits,’ says the report.

Within a decade scientists could be able to detect the merger of tens of pairs of black holes every year, according to a team of astronomers at the University of Bonn’s Argelander-Institut fuer Astronomie, who publish their findings in a paper in Monthly Notices of the Royal Astronomical Society. By modelling the behaviour of stars in clusters, the Bonn team find that they are ideal environments for black holes to coalesce. These merger events produce ripples in time and space (gravitational waves) that could be detected by instruments from as early as 2015.

Clusters of stars are found throughout our own and other galaxies and most stars are thought to have formed in them. The smallest looser ‘open clusters’ have only a few stellar members, whilst the largest tightly bound ‘globular clusters’ have as many as several million stars. The highest mass stars in clusters use up their hydrogen fuel relatively quickly (in just a few million years). The cores of these stars collapse, leading to a violent supernova explosion where the outer layers of the star are expelled into space. The explosion leaves behind a stellar remnant with gravitational field so strong that not even light can escape – a black hole.

When stars are as close together as they are in clusters, then although still rare events, the likelihood of collisions and mergers between stars of all types, including black holes, is much higher. The black holes sink to the centre of the cluster, where a core that is completely made of up of black holes forms. In the core, the black holes experience a range of interactions, sometimes forming binary pairs and sometimes being ejected from the cluster completely.

Now Dr Sambaran Banerjee, Alexander von Humboldt postdoctoral fellow, has worked with his University of Bonn colleagues Dr Holger Baumgardt and Professor Pavel Kroupa to develop the first self-consistent simulation of the movement of black holes in star clusters.

The scientists assembled their own star clusters on a high-performance supercomputer, and then calculated how they would evolve by tracing the motion of each and every star and black hole within them.

According to a key prediction of Einstein’s General Theory of Relativity, black hole binaries stir the space-time around them, generating waves that propagate away like ripples on the surface of a lake. These waves of curvature in space-time are known as gravitational waves and will temporarily distort any object they pass through. But to date no-one has succeeded in detecting them.

In the cores of stars clusters, black hole binaries are sufficiently tightly bound to be significant sources of gravitational waves. If the black holes in a binary system merge, then an even stronger pulse of gravitational waves radiates away from the system.

Based on the new results, the next generation of gravitational wave observatories like the Advanced Laser Interferometer Gravitational-wave Observatory (Advanced LIGO) could detect tens of these events each year, out to a distance of almost 5000 million light years (for comparison the well known Andromeda Galaxy is just 2.5 million light years away).

Advanced LIGO will be up and running by 2015 and if the Bonn team are right, from then on we can look forward to a new era of gravitational wave astronomy.

Sambaran comments, “Physicists have looked for gravitational waves for more than half a century. But up to now they have proved elusive. If we are right then not only will gravitational waves be found so that General Relativity passes a key test but astronomers will soon have a completely new way to study the Universe. It seems fitting that almost exactly 100 years after Einstein published his theory, scientists should be able to use this exotic phenomenon to watch some of the most exotic events in the cosmos.”

Image: An artist’s representation of the burst of gravitational waves resulting from the collision of a colliding pair of black holes. Credit: LIGO Scientific Collaboration (LSC) / NASA.

Using a few ultracold ions, intense lasers and some electrodes, researchers have built the first programmable quantum computer. The new system, described in a paper to be published in Nature Physics, flexed its versatility by performing 160 randomly chosen processing routines.

Earlier versions of quantum computers have been largely restricted to a narrow window of specific tasks. To be more generally useful, a quantum computer should be programmable, in the same way that a classical computer must be able to run many different programs on a single piece of machinery.

The new study is “a powerful demonstration of the technological advances towards producing a real-world quantum computer,” says quantum physicist Winfried Hensinger of the University of Sussex in Brighton, England.

Researchers led by David Hanneke of the National Institute of Standards and Technology in Boulder, Colo., based their quantum computer on two beryllium ions chilled to just above absolute zero. These ions, trapped by an electromagnetic field on a gold-plated alumina chip, formed the quantum bits, or qubits, analogous to the bits in regular computers represented by 0s and 1s. Short laser bursts manipulated the beryllium ions to perform the processing operations, while nearby magnesium ions kept the beryllium ions cool and still.

Hanneke and colleagues programmed the computer to do operations on a single beryllium ion and on both of the beryllium ions together. In the quantum world, a single qubit can represent a mixture of 0 and 1 simultaneously, a state called a superposition. A laser pulse operation could change the composition of the mixture within the qubit, tipping the scales to make the qubit more likely to become a 1 when measured.

Both of the qubits together could be entangled, a situation where the two qubits are intimately linked, and what happens to one seems to affect the fate of the other. Different combinations of one- and two-qubit operations made up various programs. “We put all these pieces together and asked, what can we do with the circuit?” Hanneke says.

Hanneke and colleagues chose 160 programs for the quantum computer to run. “We picked them, quite literally, at random,” Hanneke says. “We really wanted to sample all possible operations.”

The researchers ran each program 900 times. On average, the quantum computer operated accurately 79 percent of the time, the team reported in their paper, which was published online November 15. “Getting this kind of control over a quantum system is really interesting from a physics perspective,” Hanneke says.

Earlier research has estimated that to be useful, a quantum computer must operate accurately 99.99 percent of the time. Hanneke says that with stronger lasers and other refinements, the system’s fidelity may be improved.

Experimental physicist Boris Blinov says that one of the most exciting things about the new study is that the quantum computer may be scaled up. “What’s most impressive and important is that they did it in the way that can be applied to a larger-scale system,” says Blinov, of the University of Washington in Seattle. “The very same techniques they’ve used for two qubits can be applied to much larger systems.”

Sci­en­tists say they have man­aged to make plas­tics through “bio-en­gi­neer­ing” rath­er than through the use of fos­sil fu­els that con­trib­ute to glob­al warm­ing.

The find­ings are pub­lished in two pa­pers in the jour­nal Bi­o­tech­nol­ogy and Bi­o­en­gi­neer­ing to mark the jour­nal’s 50th an­ni­ver­sa­ry.

Poly­mers are mo­le­cules found in eve­ry­day life in the form of plas­tics and rub­bers. The re­search­ers, from Ko­rea Ad­vanced In­sti­tute of Sci­ence and Tech­nol­o­gy and Ko­re­an chem­i­cal com­pa­ny LG Chem, fo­cused their re­search on poly­lac­tic ac­id, a bi­o­log­ic­ally-based pol­y­mer.

“The polyesters and oth­er pol­y­mers we use eve­ry­day are mostly de­rived from fos­sil oils made through the re­fin­ery or chem­i­cal pro­cess,” said In­sti­tute re­searcher Sang Yup Lee. Poly­lac­tic ac­id “is con­sid­ered a good al­ter­na­tive to petroleum-based plas­tics as it is both bi­o­de­grad­able and has a low tox­icity to hu­mans.”

Un­til now the pol­y­mer had been pro­duced in a com­plex, costly two-step chem­i­cal pro­cess, he added. Lee’s team de­vel­oped a one-stage pro­cess in which en­gi­neered E. coli bac­te­ria pro­duced poly­lac­tic ac­id and as­so­ci­at­ed pol­y­mers through fer­menta­t­ion, a met­a­bol­ic pro­cess.

“This means that a de­vel­oped E. coli strain is now ca­pa­ble of ef­fi­ciently pro­duc­ing un­nat­u­ral pol­y­mers, through a one-step fer­menta­t­ion pro­cess,” he said.

“Global warm­ing and oth­er en­vi­ron­men­tal prob­lems are urg­ing us to de­vel­op sus­tain­a­ble pro­cesses based on re­new­able re­sources,” added Lee. “This new strat­e­gy should be gen­er­ally use­ful for de­vel­oping oth­er en­gi­neered or­gan­isms ca­pa­ble of pro­duc­ing var­i­ous un­nat­u­ral pol­y­mers by di­rect fer­menta­t­ion from re­new­able re­sources.”

What would happen if humans could deliberately create a black hole? Well, for starters we might just unlock the ultimate energy source to create the ultimate spacecraft engine — a potential “black hole-drive” – to propel ships to the stars.

It turns out black holes are not black at all; they give off “Hawking radiation” that causes them to lose energy (and therefore mass) over time. For large black holes, the amount of radiation produced is miniscule, but very small black holes rapidly turn their mass into a huge amount of energy.

This fact prompted Lois Crane and Shawn Westmoreland of Kansas State University to calculate what it would take to create a small black hole and harness the energy to propel a starship. They found that there is a “sweet spot” for black holes that are small enough to be artificially created and to produce enormous amounts of energy, but are large enough that they don’t immediately evaporate in a burst of particles. Their ideal black hole would have a mass of about a million metric tons and would be about one one-thousandth the size of a proton.

To create such a black hole, Crane and Westmoreland envision a massive spherical gamma-ray laser in space, powered by thousands of square kilometers of solar panels. After charging for a few years, this laser would release the pent-up energy equivalent to a million metric tons of mass in a converging spherical shell of photons. As the shell collapses in on itself, the energy becomes so dense that its own gravity focuses it down to a single point and a black hole is born.

The black hole would immediately begin to disgorge all the energy that was compressed to form it. To harness that energy and propel a starship, the black hole would be placed at the center of a parabolic electron-gas mirror that would reflect all the energy radiated from the black hole out the back of the ship, propelling the ship forward. Particle beams attached to the ship behind the black hole would be used to simultaneously feed the black hole and propel it along with the ship.

Such a black hole drive could easily accelerate to near the speed of light, opening up the cosmos to human travelers, but that’s just the beginning. The micro-black hole could also be used as a power generator capable of transforming any matter directly into energy. This energy could be used to create new black holes and new power generators. Obviously, creating and harnessing black holes is not an easy undertaking, but Crane and Westmoreland point out that the black hole drive has a significant advantage over more speculative technologies like warp drives and wormholes: it is physically possible. And, they believe, worth pursuing “because it allows a completely different and vastly wider destiny for the human race. We should not underestimate the ingenuity of the engineers of the future.”