Category: Materials

A Biological Supercomputer?!

cci16z_ucaeyche_1024
An artistic representation of the new biological microchip. Source: http://www.sciencealert.com/scientists-have-developed-the-world-s-first-living-breathing-supercomputer

Supercomputers are truly marvellous examples of what technology can accomplish, being used in many areas of science to work through some incredibly complex calculations. Their computational power is truly a feat of human engineering. But, unfortunately, they’re not perfect. Not only are they absolutely huge, often taking up an entire room, but they’re also expensive, prone to overheating, and a huge drain on power. They require so much of the stuff they often need their own power plant to function.

But fear not! As always, science is capable of finding a solution, and this one comes in the form of a microchip concept that uses biological components that can be found inside your own body. It was developed by an international team of researchers,  and it uses proteins in place of electrons to relay information. They’re movement is also powered by Adenosine Triphosphate (ATP), the fuel that provides energy for all biological processes occurring in your body right now. It can quite literally be described as a living microchip.

The chip’s size may not seem like much, measuring only 1.5 cm2, but if you zoom in you get a very different picture. Imagine, if you will, you’re in a plane looking down at an organised and very busy city. The streets form a sort of grid spanning from one end of the city to the other, which closely resembles the layout of this microchip. The proteins are then the vehicles that move through this grid, consuming the fuel they need as they go. The main difference being that, in this case, the streets are actually channels that have been etched into the chip’s surface.

“We’ve managed to create a very complex network in a very small area” says Dan Nicolau Sr. a bioengineer from McGill University in Canada, adding that the concept started as a “back of an envelope idea” after what he thinks was too much rum. I guess some innovative ideas require a little help getting started.

Once the rum was gone and the model created, the researchers then had to demonstrate that this concept could actually work. This was done by the application of a mathematical problem, with a successful result being if the microchip was able to identify all the correct solutions with minimal errors.

The process begins with the proteins in specific “loading zones” that guide them into the grid network. Once there, the journey through the microchip begins! The proteins start to move through the grid, via various junctions and corners, processing the calculation as they go.  Eventually, they emerge at one of many exits, each of which corresponds to one possible solution to the problem. In the specific case described by the researchers, analysis of their results revealed that correct answers were found significantly more often than incorrect ones, indicating that model can work as intended.

The researchers claim that this new model has many advantages over existing technology, including a reduction in cost, better energy efficiency, and minimal heat output, making it ideal for the construction of small, sustainable supercomputers. They also argue that this approach is much more scalable in practice, but recognise that there is still much to do to move from the model they have to a full on functioning supercomputer. It’s early days, but we know the idea works.

So, while it may be quite some time before we start seeing these biological supercomputers being actually put to use, it certainly seems like a fruitful path to follow. Society would no doubt benefit from the reduced cost and power usage that this new technology would bring, and these aspects would also make their application in scientific research much easier.

In fact, if the decrease in cost and power usage is a dramatic one, then scientists could potentially use a larger amount of these computers than they do at the moment. This a change that would have a huge impact on the kind of calculations that could be performed, and could potentially revolutionise many areas of science. Even though we’ll have to wait, that’s something I am very much looking forward.

Sources:

Advertisements

New Fuel Cell Technology keeps the Environment in mind!

I imagine you’re all pretty familiar with fuel cell technology at this point. It’s been around for quite some time and is often heralded as the answer to green, renewable energy. For the most part that is quite true, as there are a number of advantages that this technology has over current combustion-based options. It not only produces smaller amounts of greenhouse gases, but none of the air pollutants associated with health problems.

That being said, the technology isn’t perfect, with many improvements still to be made. One problem is that a fuel cell’s environmental impact depends greatly on how the fuel is acquired. For example, the by-products of a Hydrogen (H2) fuel cell may only be heat and water, but if electricity from the power grid is used to produced the H2 fuel then CO2 emissions are still too high.

The technology also requires the use of expensive or rare materials. Platinum (Pt) is easily the most commonly used catalyst in current fuel cell technology, and this is a rare metal often costing around 1000 US dollars per ounce. This really hurts the commercial viability of the fuel cell, but research regarding alternative materials is progressing.

While I’m certain these kinks will be worked out eventually, it is still worth considering other options. One such option is the Microbial Fuel Cell (MFC), a bio-electrochemical device that uses respiring microbes to convert an organic fuel into electrical energy. These already have several advantages over conventional fuel cell technology, primarily due to the fact that bacteria are used as the catalyst.

The basic structure of an MFC is shown in Figure 1, and you can see that it closely resembles that of a conventional fuel cell. In fact the method by which it produces electricity is exactly the same, the only differences are the fuel and the catalyst.

1-s2-0-s1110016815000484-gr1
Figure 1: The basic structure of an MFC. Source: http://www.sciencedirect.com/science/article/pii/S1110016815000484

The fuel for an MFC is often an organic molecule that can be used in respiration. In the figure it is shown to be glucose, and you can see that its oxidation yields both electrons and protons. It is worth noting that the species shown as “MED” is a mediator molecule used to transfer the electrons from the bacteria to the anode. Such molecules are no longer necessary, as most MFCs now use electrochemically active bacteria known as “Exoelectrogens”. These bacteria can directly transfer electrons to the anode surface via a specialised protein.

As I mentioned before, this technology has several advantages over conventional fuel cell technology in terms of cost and environmental impact. Not only are bacteria both common and inexpensive when compared to Pt, but some can respire waste molecules from other processes. This not only means that less waste would be sent to a landfill, but would actually be a source of energy. This has already be applied in some waste-water treatment plants, with the MFCs producing a great deal of energy while also removing waste molecules.

Now you’re probably thinking, “Nathan, this is all well and good, but it’s not exactly new technology”. You’d be right there, but some scientists from the Universities of Bristol and West England have made a big improvement. They have designed an MFC that is entirely biodegradable! The research was published in the journal ChemSusChem in July of 2015, and it represents a great improvement in further reducing the environmental impact of these fuel cells.

Many materials were tried and tested during the construction process. Natural rubber was used as the membrane (see Figure 1), the frame of the cell was produced from polylactic acid (PLA) using 3D printing techniques, and the anode was made from Carbon veil with a polyvinyl alcohol (PVA) binder. All of these materials are readily biodegradable with the exception of the Carbon veil, but this is known to be benign to the environment.

The cathode proved to be more difficult, with many materials being tested for conductivity and biodegradability. The authors noted that conductive synthetic latex (CSL) can be an effective cathode material, but lacks the essential biodegradability. While this meant it couldn’t be used in the fuel cell, it was used as a comparison when measuring the conductivity of other materials.

Testing then continued with egg-based and a gelatin-based mixtures being the next candidates. While both of these were conductive, they weren’t nearly good enough to be used. CSL actually performed 5 times better than either of them. But science can not be beaten so easily! Both mixtures were improved by modification with lanolin, a fatty substance found in Sheep wool, which is known to be biodegradable. This caused a drastic increase in performance for both mixtures, with the egg-based one outperforming CSL! This increase easily made it the best choice for the cathode.

With all the materials now decided, it was time to begin construction on the fuel cell. A total of 40 cells were made and arranged in various configurations. These are shown in Figure 2, and each configuration was tested to determine its performance. Of these three, the stack shown in Figure 2C was found to be able to continuously power an LED that was directly connected. It was also connected to some circuitry that harvested and stored the energy produced, and the authors report that the electricity produced by this method could power a range of applications.

4
Figure 2: a) A set of 5 fuel cells connected in parallel. Known as a “parallel set”. b) A stack of 4 parallel sets. c) A stack of 8 parallel sets. Source: http://onlinelibrary.wiley.com/wol1/doi/10.1002/cssc.201500431/full

While there is much to celebrate here, the authors also address some of the concerns associated with this technology. The most notable concern is how long the fuel cells can operate, and the authors report that after 5 months of operation the stacks were still producing power. This could potentially be longer in an application, as the operational environment of a fuel cell rarely mimics natural conditions.

They also discuss how these MFCs didn’t perform as well as some produced in other studies, but these were the first to be made from cheap, environmentally friendly materials. If anything, this research shows that such fuel cells can at least be functional, and are an excellent target for further research.

So we’ll have to wait for more research to see if this technology will actually take off, and given the timescale of this study it’s likely that we’ll be waiting quite some time. Even so, this is an important step on the road to completely sustainable living, as it shows that even our power sources could be made from completely environmentally friendly materials. Now we just have to hope people take notice. Let’s make sure they do!

Sources not mentioned in text:

A Step Forward for Wearable Electronics

3dp_graphine_image
An artistic representation of Graphene. Source: http://3dprint.com/61659/graphene-ink-capabilities/

Research on flexible, wearable electronic devices is already well under way, with products such as the Wove Band attracting a great deal of attention. In fact, it’s a field of increasing research interest due to many potential applications. These include monitoring health and fitness, functional clothes, as well as many mobile and internet uses.

Such technology could have many implications in several areas of life. These might involve more effective and immediate monitoring of patients outside hospital, potentially reducing response time if something were to go wrong, and moving communications technology into an entirely new age. The smartphone as we know could be a thing of the past once this technology takes off.

Given the plethora of uses and the high profile of the research, it’s no surprise that many materials have already been considered. Silver nanowires, carbon nanotubes, and conductive polymers have all been explored in relation to flexible electronics. Unfortunately, problems have been reported in each case, such as high manufacturing costs in the case of silver nanowires and stability issues for some polymers.

But fear not my fellow science enthusiasts! Another material has appeared to save the day. It’s one you’re probably quite familiar with by now – Graphene! This two-dimensional hexagonal array of carbon atoms has great potential in the field of flexible electronics due to its unique properties, which include great conductivity and stability. However, known production methods for the Graphene sheets that would be needed give structures with a rather high surface resistance, which is not ideal.

Luckily, the invention of conductive Graphene inks provided a way to overcome this problem. This allows for sheets of superior conductivity, greater flexibility, a lighter weight, and a lower cost. That sounds VERY good for a wearable, flexible electronic device. These inks can also be prepared with or without a binder, a chemical that helps the ink stick to a surface. This also brings advantages and disadvantages, as a binder can improve the sheets conductivity, but also requires high temperature annealing processes. This limits its use on heat sensitive substrates such as papers and textiles.

Well, a new paper published in Scientific Reports in December claims to have found a production method that doesn’t require a binder and has a high conductivity. The research was conducted by scientists at the University of Manchaster, United Kingdom, and it represents and important step forward in making flexible Graphene based electronics a reality. The production method first involves covering a surface with an ink containing Graphene nanoflakes, then drying it at 100oC. This forms a highly porous coating, which is not ideal since it leads to high contact resistance and an unsmooth electron pathway.

The authors overcame this problem by compressing the dry coating, which led to a thin, highly dense layer of Graphene. This not only improved the adhesion of the nanoflakes, but the structure became much less porous, improving its conductivity. It is also noted that greater compression led to higher conductivity values, with the highest being 4.3×104 S/m. But the science didn’t end there! The authors then went on to test how flexible electronic components made from this material would perform with regard to communications technology. Both transmissions lines (TLs) and antennae were created from the Graphene sheets, and tested in various scenarios.

TLs are conductors designed to carry electricity or and electrical signal, and are essential in any circuitry. The ones created here were tested in three positions: unbent, bent but not twisted, and bent and twisted. This was done to determine if the material performed well in various positions; a necessity for a wearable, flexible device. Turns out the TLs performed well in all three positions, with data showing only slight variations in each case.

The Graphene based antennae were also tested in various positions, both unbent and with increasing amounts of bending. In each case the antennae were found to function in the frequency range matching Wi-Fi, Bluetooth, WLAN, and mobile cellular communications. This is an excellent indication that this material could be ideal for use in wearable communications technology. It was also tested in a pseudo-real life scenario, with antennae being wrapped around the wrists of a mannequin. These results were also promising, showing that an RF signal could be both radiated and received.

So, you can hopefully see that this work represents a real step forward towards wearable electronic devices, as it shows that Graphene is truly a prime candidate. That said, there is still a great deal of work to do, such as incorporating all these components into a complete device and figuring out how to produce the technology on a commercial scale. There would also need to be more research to see if these Graphene sheets could be modified in some way to include applications outside of communications. But putting that aside, I’m quite excited about this research bringing us a little bit closer. Keep an eye out to see where it goes from here.

Sources:

  • Fuente, J. (2016). Properties Of Graphene. Graphenea. Retrieved 18 January 2016, from http://www.graphenea.com/pages/graphene-properties#.VpzceyqLSwV
  • Huang, G.-W. et al. Wearable Electronics of Silver-Nanowire/Poly(dimethylsiloxane) Nanocomposite for Smart Clothing. Sci. Rep. 5, 13971; doi: 10.1038/srep13971 (2015).
  • Huang, X. et al. Highly Flexible and Conductive Printed Graphene for Wireless Wearable Communications Applications.Sci. Rep. 5, 18298; doi: 10.1038/srep18298 (2015).
  • Matzeu, G., O’Quigley, C., McNamara, E., Zuliani, C., Fay, C., Glennon, T., & Diamond, D. (2016). An integrated sensing and wireless communications platform for sensing sodium in sweat. Anal. Methods, 8(1), 64-71. http://dx.doi.org/10.1039/c5ay02254a

The Flowers of the Future!

What do I mean by flowers of the future? I mean cyberplants! Researchers working at Linköping University in Sweden have found a way to create a rose plant with electronic circuitry running through its tissue, and the effects and implications are very interesting indeed.

Now the idea of cyberplants is not entirely new, as some research by Michael Strano at the Massachusetts Institute of Technology revealed that spinach chloroplasts can incorporate carbon nanotubes (CNTs) into their structure. The report stated that this boosted the rate of photosynthesis, as the CNTs could absorb wavelengths of light that the chloroplasts could not. So if this has been done before, what makes this new discovery special?

Well, this research is the first example of someone incorporating a working electronic circuit into a plant’s anatomy. This was done with a polymer known as PEDOT, or Poly(3,4-ethylenedioxythiophene) if you’re one of our chem nerds, and the structure can be seen below. This material is an excellent conductor when hydrated and is commonly used in printable electronics, making it an excellent contender for the cyberplant project.

pedot
The repeating unit structure of PEDOT. Source: https://en.wikipedia.org/wiki/Poly(3,4-ethylenedioxythiophene)

The researchers tested many materials before they made their choice, but none of them were ideal. Some caused the plant to produce toxic compounds, essentially poisoning it, while others clogged the plant’s water transportation systems. They eventually settled on PEDOT, which didn’t cause any noticeable problems, and found a way to incorporate it into the plant’s stem and leaves. They created the world’s first cyber-rose!

This was done by soaking each component in separate PEDOT solutions, and then manipulating them in some way to cause the polymer to migrate into the plant tissue.

In the case of the stem, natural capillary action pulled the polymer out of solution and into the plant’s vascular tissue. The natural structure of the stem then allowed the polymer to self-assemble into wires up to 10 cm long! The conductivity of these structures was then measured using two gold (Au) probes, and the performance was found to be on par with conventional printed PEDOT circuits according to Magnuo Breggren, one of the team members.

The leaves proved to be more tricky. They were first placed in a mixed solution of PEDOT and cellulose nanofibres, then a vacuum was applied. This caused all the air in the leaf tissue to be expelled, and the PEDOT then moved out of the solution and into the empty space the air left behind. This gave the leaves a very interesting property, causing the colour to shift between blueish and greenish hues when a voltage was applied.

Now, while this all seems very interesting, some scientists have questioned what the practical implications of this research could be. “It seems cool, but I am not exactly sure what the implication is” says Zhenan Bao, who works with organic electronics at Stanford University in California.

But Breggren suggests that these electronics could provide an alternative to genetic engineering for monitoring and regulating plant behaviour. While the genetic modification of plants is safe and extremely easy, certain traits, such as flowering times, might be too disruptive to an ecosystem if there is a permanent change. Especially if those changes get passed on to other plants in the area. But electronic switches would not have this risk, and could be easily reversed when needed.

However, if this research progresses to practical applications, the team would have to show that the polymers they use are not harmful to the environment in any way, and in the case of food crops, that the material doesn’t end up in any edible portions of the plant. But this may not be a problem in the future, as the team hopes to make use of biological chemicals to create the circuitry, bypassing any potential environmental and health hazards.

Given the success of their initial study, the team is now collaborating with biologists to develop their research further, and investigating any new directions it could go in. For example, Breggren is apparently investigating whether these PEDOT devices could be used to develop a system to allow the plant to act as a living fuel cell, a project he has rather amusingly named “flower power”.

Regardless of how well this research pans out in the future, it does have the value of being inherently interesting, a trait that drives a great deal of scientific research. But what really interests me, as is this case with a lot of the stuff I write about, is that this is yet another step close to the world of science fiction. We’re getting closer people! All we have to do is wait.

Sources:

New Self-Folding Material takes the Effort out of Origami

This self-folding material can walk on its own! Source: http://www.engadget.com/2015/11/09/graphene-paper-walks-laser/

I’ve never been any good at origami. Hell, I remember struggling to make a paper aeroplane when I was a kid, and I doubt I would fare much better today. But, thanks to some scientists at Donghua University in China, a new material has been invented that is capable of doing all the folding itself! Albeit into a predetermined shape. Finally! Something appropriate for my level of skill.

Self-folding materials have become a major research topic recently, with the majority of research focussing on “active polymers”. These materials are capable of converting other forms of energy, such as light or heat, into mechanical work. But they are far from seeing practical applications due to their complex production methods, unrealistic operating conditions, or complicated combinations of materials, making them fragile.

This is where this new material enters the picture! Here, the researchers have successfully created a sheet of Graphene Oxide (GO) “paper” that overcomes many of the previously mentioned problems. GO, while not quite as spectacular as pure Graphene, possesses many impressive properties, boasting both incredible strength and integrity. The paper’s self-folding properties are also capable of operating under physiological conditions, making it a prime candidate for future applications.

The material itself consists of a sheet of GO with some areas treated with Polydopamine (PDA). These treated areas act like sponges, absorbing water from the environment and swelling in humid conditions, whereas the rest of the sheet remains fairly inert. Application of heat or infrared light then causes this water to evaporate and the PDA treated areas to shrink and pull on the surrounding material, bending the paper into the designed shape. The researchers also noted the speed of this response, with a single strip of the paper able to fold and unfold in around five seconds.

Now all of that is pretty impressive, but what I find way cooler is what devices they constructed using this material. Through careful placement of the PDA treated areas, the researchers were able to create various self-folding objects, including a self assembling box and an artificial hand able to grasp and hold objects up to five times its own weight!

The most popular of these objects is the walking device shown in the gif at the top of this page. Created from a rectangular sheet of GO paper, this device has three PDA treated bands running across it that get progressively wider from front to back. When infrared light is applied, the bending of these areas causes the sheet to curve into an arch, with the rear of the paper curving to greater degree due to the varying width of the treated bands. When the light is removed, the sheet relaxes and moves forwards, with a fast response time that means five of these steps only take two seconds. You can see a video of this little robot in this Nature article on the same subject.

This technology has many potential applications including robotics, materials for sensors, and artificial muscles. One researcher in particular, Hongzhi Wang, has very high hopes for the future of this material, suggesting that it could be integrated into solar cells to build self folding panels. But, while that potential does exist, the researchers have indicated that there are still improvements to be made, as well as new questions to be answered. These include improving the 1.8% energy conversion efficiency, which remains a limiting factor, and exploring how a reduction in size will affect the properties and performance of the material.

So, while all of this COULD open the way for a new type of effortless origami, I highly doubt that it ever will. At least not any time soon. Not when there are more pressing and important applications. I mean, artificial muscles! That’s something I can’t wait to see.

Sources:

Glass Almost as Hard as Steel!

It seems like the days of finding a shattered screen after dropping your smartphone are coming to an end. You may have already heard of Gorilla Glass, the wonder material from Corning that as boinged on to the smartphone scene in recent years. But even that can fail and breakages have been reported. But as engineers strive to push what is possible for these small gadgets, so to do they find new ways to tweak and enhance the properties of glass.

Glass is usually made by heating minerals to very high temperatures and allowing them to cool, but much of the glass used in smartphones, and skyscrapers for that matter, is made stronger by the addition of metal atoms. For example, Gorilla glass is made stronger by the addition of Potassium (K), an alkali metal. But now, a team of Japanese research scientists have found a way to add an oxide of Aluminium, known as Alumina (Al2O3), to the glass structure. This oxide has long been coveted as a new candidate for making super strong glass, as it possesses some of the strongest chemical bonds known to man, with a dissociation energy of 131 kJ / cm3.

The scientists had hypothesised that adding Alumina to glass would make a super robust new material, but producing it wasn’t going to be easy. In their first attempts, adding the Alumina caused Silicon Dioxide (SiO2) crystals to form where the mix met the surface that it was being held in. These crystals made the made no longer see-through, and effectively worthless. It would be quite pointless to have a super strong glass that wasn’t see through, as that throws many potential applications right out the window, and the researchers knew this. They needed to develop a new production method.

Aerodynamic levitation is what they came up with, and it’s almost as sci-fi as it sounds. It involves holding the Alumina/glass mixture in the air while it forms by pushing it from below with a flow of oxygen gas. A laser is then used as a spatula to mix the material as it cools, and the result is a material that contains more Alumina than any glass to date, and it was found to be both transparent and reflective. Testing then revealed that the glass was very hard; harder than other oxidised glasses as well as most metals, and almost as hard as steel according to an article from phys.org.

The researchers remain hopeful that aerodynamic levitation could make it possible to produce all sorts of other super strong glasses, but first they need to figure out how to scale up the production process, as it currently only works in small batches. Nevertheless, it is nice to think that the despair you feel when discovering a broken screen may be a thing of the past. I don’t think anything will be able to live up to the integrity of those old Nokia bricks though. Those things could truly take a beating.

Sources not mentioned in text:

Artificial Skin for Robotic Limbs

Since the new Star Wars trailer has brought with it an air of Sci-Fi, I felt our next story should fit the mood. This led me to a recent article published in the journal “Science” in which a team of researchers created an incredible form of artificial skin. Currently, prosthetic limbs can restore an amputee’s ability to walk or grip objects, but can in no way restore a sense of touch. Such a sense is critical to the human experience, said coauthor Benjamin Tee, an electrical and biomedical engineer at the Agency for Science Technology and Research in Singapore. Restoring feeling in amputees and people with paralysis could allow them to carry out several activities that were previously hindered, such as cooking, contact sports etc.

A break down of the components in the Artificial Skin discussed here, and how the optical-neural interface was constructed. Credit: Science. Source: http://cen.acs.org/articles/93/i41/Artificial-Skin-Transmits-Signals-Neurons.html

Well, these researchers at Stanford University have taken us one step closer to this goal by creating an electronic skin that can detect and respond to changes in pressure. The team named this product the “Digital Tactile System”, or DiTact for short, and it consists of two main components shown in the image to the right. The upper layer consists of microscale resistive pressure sensors shaped like tiny upside-down pyramids. These structures are made from a carbon nanotube-elastomer composite capable of generating a direct current that changes amplitude based on the applied pressure. This is because the nanotube structures are capable of conducting electricity. When these structures are moved closer together, electrictity can flow through the sensor. The distance between them will vary with the applied pressure, and the greater the pressure the smaller the distance. This decrease in distance will allow for a greater flow of electricty between the structures, causing the amplitude of the current to increase.

But one problem still remains! The human brain cannot interpret this information, as it is usually received in pulsed signals, similar to Morse Code, with greater pressure increasing the frequency of these pulses. The signal therefore had to be converted into something the brain could actually recognise, which is where the second layer of the artificial skin comes into play. This layer consists of a flexible organic ring-oscillator circuit – a circuit that generates voltage spikes. The greater the amplitude of the current flowing through this circuit, the more frequent the voltage spikes. And viola! We now have a pulsed signal. But the team had to show that this could be recognised by a biological neuron, otherwise the signal would stop once it reached such a cell. To do this, they bioengineered some mouse neuron cells to be sensitive to specific frequencies of light, and translated the pressure signals from the artificial skin into light pulses. These pulses were then sent through an optical fiber to the sample of neurons, which were triggered on and off in response. This combination of optics and genetics is a field known, oddly enough, as “Optogenetics”, and it successfully proved that the artificial skin could generate a sensory output compatible with nerve cells. However, it is worth noting that this method was only used as an experimental proof of concept, and other methods of stimulating nerve cells are likely to be used in real prosthetic devices.

This work is “…just the beginning…” according to Zhenan Bao, the leader of the team, adding that they also hope to mimic other sensing functions of human skin, such as the ability to feel heat, or distinguish between rough and smooth surfaces, and integrate them into the platform, but this will take time. There are a total of six types of biological sensing mechanisms in the hand, and this experiment reports success in just one of them. Nevertheless, the work represents “an important advance in the development of skin-like materials that mimic the functionality of human skin on an unprecedented level” according to Ali Javey, who is also working on developing electronic skin at the University of California, Berkley. Adding that “It could have important implications in the development of smarter prosthetics”.

With thought-controlled robotic limbs already being very real, this research represents the next key step in producing completely functioning prosthetic limbs, that could one day be almost indistinguishable from the real thing! Imagine being able to regain all forms of sense and movement in a limb you had once thought lost forever. That would be HUGE, and could drastically improve the quality of life of many amputees. Unfortunately, such a mechanical marvel is still very much in the future, but this research is an important stepping stone, and I wouldn’t be surprised if we start hearing more about this technology in the years to come. My next question would be, once we have achieved all of this, will we start working on a prosthetic arm able to mimic the effects of using The Force? I think we should make and arm that can use The Force! I think we all (secretly) want that.

Sources not mentioned in text:

Chemical Analysis of Mars from Orbit? But how?!

When I found out that water had been found on Mars my first response was to flail and shout with excitement. But once I had calmed down I started to think; how does one actually go about analysing the surface of another planet without actually being on the surface yourself? It was then that I found out NASA have managed to do all of this using a satellite currently orbiting the red planet at an altitude of 300 km (186 miles)! That’s some pretty impressive tech right there (and I imagine the specs are a well-kept trade secret). The satellite itself is known as the Mars Reconnaissance Orbiter (MRO), and it’s equipped with an analytical tool known as CRISM, or the “Compact Reconnaissance Imaging Spectrometer for Mars” if you’re feeling excessive. This device can detect and measure the wavelengths and intensity of both visible and infrared light that has been reflected or scattered from the martian surface; a technique known as “Reflectance Spectroscopy”.

Reflectance Spectroscopy functions on the principle that when light comes into contact with a material, the chemical bonding and molecular structure will cause some of this light to be absorbed. The exact wavelengths absorbed will vary depending on the type of bonding and the elements involved, and the remaining light will either be scattered or reflected depending on the macro-scale properties of the material, such as shape and size. On Mars, most of these materials seem to be grains of some sort and the potentially complex shape of such a structure can cause the light to be scattered in all sorts of directions. However, some of this light will reach the MRO, and CRISM can then detect and measure which wavelengths have been absorbed based on a decrease in intensity. How they found a way to do all of this FROM ORBIT still mystifies me, but I imagine NASA prefers it that way. This whole process then gives an output known as an “absorption spectrum”, an example of which is shown in Figure 1.

Figure 1: An example of an absorption spectrum showing wavelength (x-axis) and reflectance (y-axis). Source: CRISM website: Link: http://crism.jhuapl.edu/instrument/surface/sees.php

So! What have they actually found on Mars using this technique? Well, they appear to have detected “Aqueous Minerals”, which are chemical structures that form in the presence of water by chemical reaction with the surrounding rock. The exact mineral that will form is determined by many factors, including the temperature, pH, and salt content (salinity) of the environment, as well as the composition of the parent rock. Given that this process takes an extremely long time to occur naturally, it can show where water has been present long enough to cause such a reaction, and can give an excellent indication of what the martian surface was like in the past. For example, chloride and sulfate minerals generally indicate very saline water, as well as suggesting that it was more acidic, whereas phyllosilicates and carbonates suggest less salinity and a more neutral pH. What I find most exciting is that this data can suggest where to begin looking for fossilized evidence of ancient life (if it existed at all). If the past water appears to not be too acidic and the elements for life are present, then it is certainly a possibility.

It seems that Mars just keeps getting more exiting with each new discovery, and all we can do now is wait for next announcement to be made. Here’s hoping it’s evidence of life! Also, speaking of life on Mars, everyone should go see The Martian movie in cinemas now, it’s f**king brilliant!

Sources:

  • The CRISM Website. Link: http://crism.jhuapl.edu/index.php
  • USGS Spectroscopy Lab – About Reflectance Spectroscopy. Link: http://speclab.cr.usgs.gov/aboutrefl.html
  • PBS Newshour. “Mars has flowing rivers of briny water, NASA satellite reveals”. Link: http://www.pbs.org/newshour/rundown/mars-flowing-rivers-briny-water-nasa-satellite-reveals/
  • NASA Mars Reconnaissance Orbiter Website. Link: http://mars.nasa.gov/mro/