

Evaluation of the results of the latest research in the field of biomechanics in terms of their innovative capacity (continuation, the second article)

Andrew (Gabriel) Livshits

Biomedical Innovation technology - the future of the industry of drugs and medical devices, biotechnology is the future of microscopic robots, the thousands of the latest products of mass consumption, there are millions of new jobs

More than any other industry, biomedical technology has the ability to flourish on the basis of research subjects wildlife

Over the past year has received many important results of this kind of research and experimentation, I will give information on some of the most successful

Engineers at the Massachusetts Institute of Technology have created a photovoltaic power generation, which oxidizes glucose from the cerebrospinal fluid. The work of scientists published in the journal PLoS ONE, and its summary retells Science Now.

Square chip area of one square millimeter or two provided the cathode, anode and the membrane separating them. A platinum anode glucose is oxidized to form hydrogen ions and electrons.

The membrane separating the cathode and anode is permeable only to hydrogen ions but not for electrons. Ions rush through the membrane to the cathode and combine it with oxygen to form water. Electrons are also rushing to the cathode, but not through the membrane, and a microchip circuitry and thus feed its energy.

The anode of the microchip was made of platinum and used for the production of carbon nanotube cathode. Created by the authors tested the device in a solution composed of simulated cerebrospinal fluid.

The microchip was able to produce a few hundred microwatts of electrical energy, and the glucose consumption remained relatively small. According to calculations of the researchers, it will be from 3 to 28 percent of the volume is constantly regenerated in the brain glucose. The oxygen consumption of the device is also significantly influenced by its concentration in the cerebrospinal fluid.

According to the authors, by the batteries can be useful for electric power supply machine - brain interface in patients with blindness or profound brain damage. At present all the experimental devices of this kind are powered by wireless induction electricity or batteries that need to be replaced periodically during surgical procedures.

Microchips, producing energy from glucose, in the future be able to make such devices completely autonomous.

In other studies and experiments, researchers discovered how damaged neurons attract microglial cells to help regenerate nerve tissue. The paper was published in the journal Developmental Cell, its summary results Science-Now.

Biologists are working on a model object - zebrafish brain-rerio (zebrafish, Danio rerio), the genome of which were made of fluorescent protein genes. The neurons of such animals synthesized fluorescent protein red and accessory cells of nervous tissue (called microglia) - green. Since the brain for juvenile zebrafish Danio-transparent, then the behavior of the cells can be observed directly through a microscope.

If the damage of one of the neurons of the laser, the nearby microglial cells rushed to him, surrounded and absorbed the remnants of dead cells. Removal of dead neurons - an important step in the regeneration of nerve tissue.

Scientists have found that the involvement of microglial cells is always accompanied by the spread of the calcium wave - increase in the content of Ca2 + in the neighboring neurons. It normally applies a rate of about 1 millimeter per minute.

If you block Ca2 + entry into the nerve cells, the calcium wave and there is no longer involved in the microglia dead neurons. Trigger that triggers a calcium wave that was the neurotransmitter glutamate, which came out of the damaged neurons in the extracellular space - his blocking also inhibited the migration of microglia.

Published work is important for understanding normal development, regeneration and propagation of signals in the brain. In addition, processes of migration of microglia may play a role in the occurrence of neurodegenerative diseases. However, to define this role, scientists will have to switch to the human brain, because fish do not suffer from Alzheimer's and Parkinson's.
Some studies make for a fresh look at the stereotypes of the structure of the components of wildlife
Especially a lot of surprises pripodnosit nature study of various microorganisms

Scientists on the example of oceanic bacteria found that free-living microorganisms get in populations that are facing each other "war" with antibiotics. The results were published in the journal Science, a brief description is provided in the same place in an editorial.

As model organisms were oceanic bacteria genus Vibrio. Within this genus there are several species that, in turn, are divided into many strains with the same genome. The researchers were able to isolate and identify the DNA sequence of 185 different strains of bacteria micro-populations: those that live in the water column or on the surface of the sea plankton.
The authors analyzed the relationship between different strains: a solution to the bacteria of one genotype was applied to plates with colonies of related bacteria and watched as one strain inhibits the growth of another.

It is known that more genetically distant organisms usually inhibit the growth of each other. The study, however, showed that, among the variety of strains studied there is a sharp genetic threshold, which determines whether the relationship between bacteria hostile or friendly.
Vibrio bacterial community was divided into micro-population who "fight" each other with antibiotics. Contrary to the expectations of the researchers, these micro-population composed not only of genetically identical offspring of a single cell, but also of their close relatives. Moreover, the relatives themselves sometimes did not produce an antibiotic that protects the population from the competition.

Antibiotics are essential to the ecology of microorganisms, which, however, is very difficult to study. It is known that between the generating, sustainable and sensitive to a particular antibiotic, bacteria occur pairwise relations of domination (like playing rock-paper-scissors). In the laboratory, such domination is simplified population. In nature, the dominance is never absolute, since the real community of bacteria divided into micro-population. The small difference in the lives of each micro-population guarantees diversity of the community.

Energy of living organisms, especially in the processes of reproduction and regeneration was also an important focus of research and promising
Jeremy England, a physicist at the Massachusetts Institute of Technology, proposed a way to calculate the amount of energy required for the reproduction of life. His estimates showed that RNA replication thermodynamically much simpler than DNA replication and, therefore, should be used. The results indirectly support the hypothesis RNA world, not yet been published in a peer-reviewed journal. Preprint available on the website of Cornell University. Briefly about it writes the blog Technology Review.

Thermodynamic calculations based on the statistical evaluation of the biological system before and after replication. With complete information about the possible state of the particles in the system, in which the existence of life is acceptable, we can calculate the amount of heat required to replicate. Statistically evaluating this condition, a physician in the calculations of the thermodynamic definition of life escaped, having taken out his brackets thought experiment (assumed to separate the living from the dead always external expert).

Scientists estimate that the thermodynamic point of view, RNA replication is much easier to replicate DNA. At the dawn of life likely in RNA replication was significantly higher than that of DNA, which indirectly supports the hypothesis of RNA world. According to her, the first samovosprovoizvodyaschiesya system consisted of RNA, which also was the bearer of hereditary information and machine for its reproduction. Division of labor was much later, when DNA was used as a reliable store of information (it is chemically stable than RNA), and enzymatic functions transferred to proteins.

In addition, England was possible to estimate the energy efficiency of replication of the bacteria. According to the scientist, Escherichia coli to replicate spends only 2-3 times more thermodynamically calculated minimum. However, not in front of all kinds of bacteria are the problem of maximal energy optimization (many microbes spend energy just to speed up biochemical processes).

Maybe for extremely slow-growing bacteria ocean bottom energy efficiency of replication may be even more impressive than the relatively prosperous E. coli.
Based on the already acquired knowledge and experience in the study and the structural analysis of the kinematics of living organisms, skillfully combining the latest construction materials and composites, the researchers created a fundamentally new and innovative subjects, details of which only a few years ago would have been considered and would be seen as unjustified fantasy

Scientists at the National Laboratory Lawrence Berkeley have created a microscopic drive based vanadium oxide, the specific strength is higher than the force of human muscles by three orders. The paper was published in the journal Nano-letters, and a summary of its results in the laboratory site.
The invention of the drive was an unexpected result of the scientists involved in the phase transition in vanadium oxide. This material when heated above 65 degrees from an insulator becomes a conductor. Thus, as the authors found, the transition is accompanied by compressing the material in one and the expansion in the other two directions.
Usually when creating electronic devices compressibility is undesirable because it can cause loss of contact. However, it allows the use of vanadium oxide to create microscopic drives tiny cars.

In the authors created a prototype of the drive, there are eight bands of vanadium oxide, coated on one side of the metal chromium. Heating is one of the bands at 15 degrees Celsius (with current or laser beam) leads to the fact that it bends like fingers on a hand. With the simultaneous heating of all stripes prototype performs characteristic grasping movements.

The authors argue that the same mass, the force developed a new drive, a thousand times greater than muscle power animal. Compared to the standard in micro--technology piezoelectric actuator, vanadium is much easier, requires less voltage, and its range reduction (Δl) is much greater.
Mechanical drives used in micro-technology, very different from those of macroscopic devices. Interestingly, only some of them are power-driven in the full sense of the word. For example, the biological "molecular machines" as such are not usually because their work is based on the chemical affinity and does not imply conservation of inertia.

Very often now the structure and properties of live bacteria used to create micromotors
The new design of micro-motor, built on the basis of live bacteria, offered Metin Sitti (Metin Sitti) and Bahar Beckham (Bahareh Behkam) of Carnegie Mellon University (Carnegie Mellon University) in Pennsylvania, United States.

As the researchers have published an article in Applied Physics Letters, referred to by the New Scientist Tech, in the proposed device is activated bacteria with a long rotating flagellum, which normally causes the bacterium "screwed" in the surrounding liquid.

The whole organism is secured in a plastic mikrostanine by electrostatic, van der Waals and hydrophobic interactions. The design is placed in a solution of glucose, which harbor bacteria. Velocity reached by such a system is 15 microns per second.
To stop solution is added to copper sulphate. To restore mobility bacteria, copper is taken common solvent - ethylenediaminetetraacetate (EDTA). So you can turn on and off the rotation indefinitely.

The use of mobile nano-robots on bacterial rod of similar design, the authors consider a promising drug delivery on urinary ways, the spinal canal through the conjunctival and oral cavity ear. Perhaps the use of the proposed innovation and researchers to examine the technical mikrotruboprovodov in nuclear power engineering and aerospace instrumentation.

Based on the same methodology, a group of Japanese scientists led by Yuichi Hiratsuka (Yuichi Hiratsuka) created a micro-motor driven by the bacteria, according to the publication Live Science referring to the "Proceedings of the National Academy of Sciences' USA. Motor development was carried out jointly by the National Institute of Advanced Industrial Science and Technology of Japan (National Institute of Advanced Industrial Science and Technology) and the University of Tokyo.

Miniature motor shaft rotates moving bacteria Mycoplasma mobile. With its own length about one micron, mycoplasma this species can move at a speed of up to 1.8 inches per hour. Motor fuel is glucose, which supplies mycoplasma.

Microbes rotated 20,000 quartz rotors mounted on a silicon chip. Each motor has a diameter of about 20 nanometers, that is five times smaller than a human hair.

Mycoplasmas are attached to the rotor micromotor vitamin B7. Microbes move in special guides glikilirovannyh of protein molecules. In the genome of Mycoplasma changes that make them more resistant to these guides. This is the first nanotechnology development, including a mechanical device and a living organism.

Rotation speed of the motor is 1.5 to 2.6 rpm. Scientists have managed to achieve a record low torque: it 10,000 times smaller than the smallest of modern electric motors.

Development of Japanese scientists in the near future can be used in a variety of nano-machines to generate small currents or as a drive microscopic pumps.

Further work Hiratsuka going to get to work in their engines dead bacteria. This is in order to nanodvigateli could not represent epidemiological risk.

Surprising results show, motors postroennye at the molecular level and scale factor
Molecular motor that can move at 10 000 times its body, designed by Dutch physicists reported Physics Web. Scientists from the University of Groningen, Eindhoven and Research Center Phillips made single molecules rotate glass rods up to 28 thousandths of a millimeter.

Nanomotors driven by heat and light, under the influence of which it changes shape.
Experimenters placed a substance on the structure close to the common dyes inside the liquid crystal film, where the ultraviolet rays of the molecule becomes the property of "mirrored".

In this case, both the source and the final form rather "twisted" compared to the transition state, and the film is an energy "unwinding." Full turn requires four stages, two of which ("light") are considered to be relatively rapid, and two ("thermal") - slow.

They all take a few minutes.
The authors note that while the movement and possibly due to the action of several molecules, these actions must be regarded as consistent, but a system of molecules in the film - the whole engine.

With these mechanisms Nanoengineering hope "repair" cells or building their microscopic structures, and have tried as motors biomolecules and even microorganisms

The analogy with some of the phenomena of nature helps to create nano-technologies and products, built on the base and in the inherent scale factor, which is already a classic nano-technologies

U.S. nanotechnology with carbon nanotubes reproduce material, which covered limbs of geckos, the website WorldChanging.com. It is known that the lizard can run up the steep wall, and some time ago, biologists were able to explain this feature of the device of the skin on the feet of animal: it formed a special bristle, reversible "sticking" to most surfaces.

The effect itself is easy to explain: the surface of the bristle "adjusted" by the microscopic roughness, so that the contact area is maximized. Between particles "bristle" and "walls" are the so-called van der Waals forces - the same as the binding molecules in the liquid.

Despite its simplicity, an artificial material with the desired properties for a long time is difficult. In the animal bristle filaments are composed of a protein whose structure is read from is responsible for carrying the genetic information of DNA, so that to reproduce the process that scientists just was not possible.

Problem was solved by the staff of the University of Akron (Ohio, USA): they have grown on the surface of the polymer, "forest" of multiwalled nanotubes - of nested cylinders, formed a two-dimensional network of carbon atoms. First, researchers paid attention to unusual ratio of length and diameter of these structures and use them where were necessary "nanowires", "nanokanal" or "nanowire".

The new material has turned out 200 times more "sticky" than the original, but "peeling off" does not collapse due to the extreme strength of nanofibers.

In his article, the researchers point out that the material can find a variety of applications: if the result is confirmed, "reversible sverhkley" will be immediately claimed by engineers. The difficulty is that the production of nanotubes is extremely expensive, and so far only a few products based on them are used outside the laboratory.

Research in the field of nano-technology and requires sootvntstvuyuschego equipment and tooling

In this sector, there were new technologies

British physicists, materials scientists have created the smallest tube in the world and put her in the Guinness Book of Records. According to BBC News, David Britz from Oxford University and his colleague Andrew Hlobystovu University of Nottingham, managed to hold the chemical reaction in a test tube, "made" of carbon atoms.

CNT length of two-micron diameter of 1.2 nm and a piece of graphite in the atom thick, which is rolled into a cylinder. The results of the reactions taking place in the tubes can only be observed under the electron microscope, because nanotubes are so small that a pin head can fit them tens of billions.

The new technology can be used in the synthesis of polymers, in which individual molecules of the substance are connected to each other in long chains.

Scientists have experimented with molecules bakminsterfullerenov oxide, which normally connected in a branched polymer, like a tree. However, during this reaction in the nanotube molecules form a straight line because the tube wall did not allow them to branch out.

The result is a polymer of a higher quality than those obtained in conventional tubes. Scientists believe that in the long term in nanotubes can be synthesized many important scientific and industrial polymers, such as polyethylene, whose molecular shape is easy to control.

useful info? Press:

more articles...
© Yaroslav Vashchuk, 2003-2011
сайты Хмельницкого bigmir)net TOP 100