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Seaweed brain gel
When defects in the brain’s blood vessels occur such as aneurysms rapid surgery may be needed, which can put other parts of the brain at risk.
Now scientists from the University of Michigan have developed Algel, a material made from seaweed that can be injected into the brain to stabilise malformed blood vessels, making them safer and easier to treat surgically.
Algel hardens vascular lesions, including aneurysms, to a “soft gel consistency”, which is biologically benign and could be used to fill or plug up blood vessels without triggering an immune response.
Aneurysms, formed by the dilating or ballooning of blood vessels are particularly dangerous because they increase the chance of arterial rupture and subsequent bleeding into brain tissues. This leaked blood then clots leading to a stroke which itself bring on severe disability or death.
Currently, patients with lesions in the brain are treated either through surgery or through newer endovascular treatments. Surgery risks the possibility of damaging other brain structures. Endovascular treatments are less risky but typically require the use of non-organic materials not really in tune with the environment of the inner brain such as platinum coils, which are used to fill aneurysms, or cyanoacrylate derivatives, used as a superglue.
Contrastingly, Algel is a sugar-based polymer derived from alginate, a natural material that is more than 95 per cent water. It is non-adhesive, non-toxic and has tissue-like properties. Algel is injected as a liquid through microcatheters into vascular defects wherupon it forms a gel which is strong, soft, non-adhesive and biocompatible.
The makers of the Algel - Daryl Kipke, associate professor and director of the Neural Engineering Laboratory in the Department of Biomedical Engineering, and post doctoral fellow Timothy Becker - have sold the technology to WL Gore & Associates, the makers of Gore-Tex - the material used in all-weather gear, and the company is set to embark on Phase I trials of the substance.
Do you want to relive some of your favourite smells?
A new smell recorder may help you do just that, allowing you to record a smell and then replay it back later.
According to New Scientist, scientists at the Tokyo Institute of Technology are developing the gadget. Pointing the device at a smelly object will prompt it to analyse its aroma and reproduce it using a mixture of non-toxic chemicals.
Smell generators have been developed in the past for use in PC games or TV gameshows but they used preset smells. The new device attempts to reproduce the odours detected by the 347 olfactory sensors available to humans.
The system uses 15 electronic noses - chemical sensing microchips - which pick up the odours and create a digital recipe from a series of 96 chemicals which can be chosen according to what purpose the device is being used for. To replay a smell, samples of the particular chemicals are mixed up, heated and vaporised.
So far the technology has been able to record and playback the smells of a selection of fruit and can even tell the difference between green apples and red apples, according to the developers.
They foresee the system enhancing the experience of online shopping by allowing you to sniff foods or perfumes or other areas when a virtual reality environment needs to be needs that extra dimension.
Tiny tools allowing scientists to build three-dimensional nanostructures have been developed and demonstrated by researchers at the Technical University of Denmark.
2D nanostructures can be made by pushing components together on a smooth surface but the building of 3D structures is essential if we are going to be able to build the nano-machines of the future.
3D structures have been difficult to make because they require a more precise manipulation and assembly.
Until recently, 3D nanoscale devices could only be built through chemical reactions - not ideal because adding extra chemicals may change the electrical or mechanical properties of the structure.
Now the university’s nanotechnology team has built a set of tools to allow assembly through a “pick-and-place” method, basically picking up and placing individual components one by one in the order desired.
Chief among these tools is a micrometre-sized “gripper” that can be opened and closed by placing a small amount of static charge on the prongs.
The force of its grip is only about a millionth of a Newton, but this more than enough to overcome the natural adhesion of a nanowire to the surface it is lying on.
The tools can be fabricated en masse and are advancing all the time, the developers say. New versions of the gripper have several activation modes allowing a greater control over the applied force and providing a channel for feedback to the tool’s operator.
The scientists claim the tools are also easy to use. In recent high school demonstrations - students shown the equipment were picking up and placing nanowires within hour or two.
The developers hope that eventually the technology will lead to nanotechnology workshops equipped with a whole set of tools allowing engineers to build complex nano-machines.
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