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March 17, 2006

Other tech: Magnetically inflated cables for large space structures

Magnetically inflated cables can spring open a large (kilometer or larger) membrane space structure This can be used to make massive space telescopes, solar power collection systems, solar thermal propulsion and many other structures. This looks like one of the most simple and straight forward yet highest potential of all of the new Nasa institute of Advanced Concept ideas. This idea and the plasma magnets look like major winners.

Solar electric power systems at 10km in diameter could generate 18 GW at 20% efficiency. Networks of powered and cooled superconducting cables that would hold massive structures rigid in space. Existing superconducting cable should work. Better superconducting cable can make the systems work even better.

Electrodynamic- low propellent space propulsion

Advancement on powered tether propulsion. Improved for movement in all directions and the structure can be used for other functions The article also has an interesting analysis of power storage systems now and near term.

Nanotech space propulsion- enhanced when molecular nanotechnology arrives

Scalable flat panel nano-particle propulsion is and advancement of ion drive Different size particles are used to get maximum efficiency and to optimize either specific impulse (speed of propellant) or the amount of acceleration force.

March 16, 2006

Other tech: Fast communications - optical/wireless

Telecommunications researchers have demonstrated a novel communications network design that would provide both ultra-high-speed wireless and wired access services from the same signals carried on a single optical fiber. The system could provide 32 different channels, each providing 2.5 gigabit-per-second service. That capacity is already working in the lab.

Using a technique developed at Georgia Tech, wireless and baseband signals carried by multiple wavelengths would be converted onto the millimeter-wave carrier simultaneously. The conversion would be done using one of several all-optical techniques such as external modulator, four-wave mixing (FWM) or cross-phase modulation (XPM) that would not require costly high-frequency electronic devices. The resulting signal would be split into two components and carried by passive optical network (PON) infrastructure installed throughout a building.

One component of the signal would be detected by high-speed receivers built into the ceilings of rooms, then amplified for short-range wireless transmission at frequencies of 40 to 60 gigahertz. The other signal component carrying identical information would be accessed through standard wall outlet throughout the building using a low-cost receiver and optical filter.

Either way, users could receive signals at data rates of up to 2.5 gigabits per second.

nanoscale technology: Artificial muscle advance

Researchers at the University of Dallas have created alcohol- and hydrogen-powered artificial muscles that are 100 times stronger than natural muscles, able to do 100 times greater work per cycle and produce, at reduced strengths, larger contractions than natural muscles. Among other possibilities, these muscles could enable fuel-powered artificial limbs, "smart skins" and morphing structures for air and marine vehicles, autonomous robots having very long mission capabilities and smart sensors that detect and self-actuate to change the environment. The team from UTD's NanoTech Institute developed two different types of artificial muscles that, like natural muscles, convert the chemical energy of an energetic fuel to mechanical energy. The fuel-powered muscles can be easily downsized to the micro- and nano-scales, and arrays of such micro-muscles could be used in "smart skins" that improve the performance of marine and aerospace vehicles. By replacing metal catalyst with tethered enzymes, it might eventually be possible to use artificial muscles powered by food-derived fuels for actuation in the human body – perhaps even for artificial hearts. Darpa is interested in using this advancement for autonomous humanoid robots that protect people from danger, artificial limbs that act like natural limbs and exoskeletons that provide super-human strength to firefighters, astronauts and soldiers -- all of which are able to perform lengthy missions by using shots of alcohol as a highly energetic fuel.

Another prediction appears closer to happening: Success in getting rid of nuclear waste

The plan is to build a “sub-critical” nuclear reactor. Such a reactor would not be able to sustain a chain reaction. Instead, the nucleus-transmuting subatomic particles would be supplied from outside, using a particle accelerator.
Facilities, which will probably cost around $1 billion each, are being planned by physicists in Japan and Europe to come on stream some time after 2015.

About 95% of the mass of a piece of used nuclear fuel is unconverted uranium, so the first step is to extract the 5% that is waste. This is done chemically. The radioactive elements to be transmuted are then turned into a target for protons fired out of a particle accelerator. Neutrons cannot be speeded up in an accelerator because they have no electric charge to grab hold of. But the main role of the protons is to knock neutrons free from nuclei in the target.

These neutrons should, if all goes well, be absorbed by the technetium and other fission products, transmuting them into new elements. They will also break up the elements heavier than uranium into products similar to those from uranium fission. Although, initially, the new elements will be more radioactive than the spent nuclear waste was, that radioactivity will last only a few hundred years. This means that the dumps into which they are put need not be as secure (or as expensive) as those envisaged for long-term waste-storage. And, as a bonus, the whole process should generate more energy than it consumes

March 15, 2006

DNA nanotechnology: Follow up on DNA Origami breakthrough

The DNA origami steps are described

In Rothemund's method, a long strand of DNA snakes back and forth until it forms a desired shape. The key to getting the DNA to form this way, and to holding it in place, are short "staples" of DNA with sequences chosen to attach to specific parts of the long strand. Rothemund divides the long strand into sections; then a staple might attach to sections 86 and 112, for example, bringing them together and causing the long strand to fold. A couple of hundred unique staples can fold the DNA into just the right shape.

1. A computer program takes care of identifying the sequences the staples (which will hold together the structure) needs to have.
2. The desired structure is designed on the computer. It spits out a set of 250 DNA sequences.
3. They are ordered online. The sequences come in the mail in a bunch of little tubes.
4. You mix them together along with the long strand of DNA, add some salt, heat it up to boiling and cool it down to about room temperature, and then it's done.

Once mixed together, the strands of DNA assemble themselves into the desired structure.

Such self-assembly methods can be used to make any shape or pattern measuring 100 nanometers across or less, and with features about 6 nanometers apart. Rothemund's work has taken the small field of DNA nanotechnology and opened it up to becoming a mainstream tool by making it one or two orders of magnitude cheaper and easier to do.

Other work with DNA that could enhance DNA Origami towards more powerful DNA Nanotechnology.
Programmable DNA manipulator, Ned Seeman
Self assembled pyramids and other building blocks shaped from DNA
DNA and nanotubes
DNA wrapped nanotubes
Modifying DNA with Enzymes

State of nanoscale medicine

James Baker designs nanoparticles to guide drugs directly into cancer cells, which could lead to far safer treatments. Cancer therapies may be the first nanomedicines to take off. Treatments that deliver drugs to the neighborhood of cancer cells in nanoscale capsules have recently become available for breast and ovarian cancers and for Kaposi's sarcoma. The next generation of treatments, not yet approved, improves the drugs by delivering them inside individual cancer cells. This generation also boasts multifunction particles such as Baker's; in experiments reported last June, Baker's particles slowed and even killed human tumors grown in mice far more efficiently than conventional chemotherapy. Baker has already begun work on a modular system in which dendrimers adorned with different drugs, imaging agents, or cancer-targeting molecules could be "zipped together." Doctors might be able to create personalized combinations of medicines by simply mixing the contents of vials of dendrimers.

Such a system is at least 10 years away from routine use, but Baker's basic design could be approved for use in patients in as little as five years. That kind of rapid progress is a huge part of what excites doctors and researchers about nanotechnology's medical potential.

Raoul Kopelman -- Nanoparticles for cancer imaging and therapy
University of Michigan

Robert Langer -- Nanoparticle drug delivery for prostate cancer
MIT

Charles Lieber -- Nanowire devices for virus detection and cancer screening
Harvard University

Ralph Weissleder -- Magnetic nano-particles for cancer imaging
Harvard University

other tech: Diffusion Tensor Imaging on the path to more detailed brain scans

Another example that new more precise tools can help reveal important details of problems such as disease.

Diffusion tensor imaging (DTI) a variation of magnetic resonance imaging (MRI) that allows the study of the connections between different brain areas. Conventional imaging techniques, such as structural MRI, reveal major anatomical features of the brain -- gray matter, which is made up of nerve cell bodies. But neuroscientists believe that some diseases may be rooted in subtle "wiring" problems involving axons, the long, thin tails of neurons that carry electrical signals and constitute the brain's white matter. With DTI, researchers can, for the first time, look at the complex network of nerve fibers connecting the different brain areas. Memory and cognitive problems associated with schizophrenia , major but undertreated aspects of the disease, are linked to flaws in nerve fibers near the hippocampus. In DTI, radiologists use specific radio-frequency and magnetic field-gradient pulses to track the movement of water molecules in the brain.

Nanobiomechanics

Nanomaterial tools are being applied to medicine.

Medical researchers have long known that diseases can cause -- or be caused by -- physical changes in individual cells. For instance, invading parasites can distort or degrade blood cells, and heart failure can occur as muscle cells lose their ability to contract in the wake of a heart attack. Knowing the effect of forces as small as a piconewton -- a trillionth of a newton -- on a cell gives researchers a much finer view of the ways in which diseased cells differ from healthy ones. A pioneering group of materials scientists are working closely with microbiologists and medical researchers to learn more about how our cells react to tiny forces and how their physical form is affected by disease.

Infected blood cells become more rigid, losing the ability to reduce their width from eight micrometers down to two or three micrometers, which they need to do to slip through capillaries. Rigid cells, on the other hand, can clog capillaries and cause cerebral hemorrhages. Using optical tweezers, which employ intensely focused laser light to exert a tiny force on objects attached to cells, Subra Suresh and his collaborators showed that red blood cells infected with malaria become 10 times stiffer than healthy cells -- three to four times stiffer than was previously estimated.

Beyond RFID: Dedicated Short Range Communication

ABI research discusses new real time traffic systems including dedicated short range communication DSRC is a two-way network that sends more data about the vehicle itself and road conditions to listening points along the highway. Advances beyond RFID can add more memory to record and track item location history. Research on the RFID market indicates that usage of RFID will explode when RFID tag prices are less than a penny. This is expected by 2009 Recent RFID pricing is 7.2 cents per tag in orders of 10 million China is issuing RFID identity cards. The new ID cards can be read by a reader that is within 20 centimeters to 30 centimeters of the card. The cards are used to store basic personal information, such as name and birth date.

Improving tools and imaging capability

There has been advance that allows the gathering of quantitative, real-time information on protein expression in living cells at the single-molecule level. This will allow a deeper understanding of the body and biology at the molecular level. Understanding at a real-time and molecularly precise level is useful to learn how to better control and utilize those processes.

Chemists at Harvard University have developed the first technique providing a real-time, molecule-by-molecule "movie" of protein production in live cells. Their direct observation of fluorescently tagged molecules in single cells -- providing striking real-time footage of the birth of individual new protein molecules inside -- greatly increases scientists' precision in probing genetic activity. Using the new assay, described this week in the journal Science, researchers led by Harvard's X. Sunney Xie counted, one by one, protein molecules generated in small bursts within cells as multiple ribosomes bound to single copies of mRNA complete the process by which DNA, an organism's long-term genetic repository, yields its crop of proteins. These random, or stochastic, bursts of protein expression are described in detail in a separate paper Xie and colleagues present this week in Nature.

Society: Cosmetic surgery statistic that suggests that human enhancement will be welcome

Cosmetic surgery statistics show 10.2 million cosmetic surgery procedures were performed in 2005 in the United States I interpret this to mean that people will be seeking out performance and appearance enhancement via gene therapy and other technology as it is available.

other tech: 3 nanometer channel length transistor

Scientists at the National Nano Fab Center at the Korea Advanced Institute of Science and Technology (KAIST) have developed the world’s smallest transistor, with a channel length of 3-nanometers, according to a Korea Herald report. The device is a three-dimensional FinFET. This will allow the development of terabit memories. It could allow conventional silicon integration to provide processors that run at 100-GHz. It could delay the time when a trasition to more exotic technologies such as carbon nanotubes or information processing within molecular materials is needed.

Towards nanomedicine: Bone Cell grown on carbon nanotubes

Bone cells grown on carbon nanotubes Because carbon nanotubes are not biodegradable, they behave like an inert matrix on which cells can proliferate and deposit new living material, which becomes functional, normal bone, according to the paper. They therefore hold promise in the treatment of bone defects in humans associated with the removal of tumors, trauma, and abnormal bone development and in dental implants, Zanello added.

More research is needed to determine how the body will interact with carbon nanotubes, specifically in its immune response, the paper states.

Carbon nanotubes could be used as a scaffold for new bone.

DNA nanotechnology: DNA oragami example of current capability

Impressive progress is being made towards DNA nanotechnology.

A map of the Americas measuring just a few hundred nanometres across has been created out of meticulously folded strands of DNA, using a new technique for manipulating molecules dubbed "DNA origami". More information is here The "DNA origami" procedure laid out by Paul Rothemund of the California Institute of Technology could be adapted to create nano-computers, new drug delivery systems or even molecular-scale chemical factories. Rothemund said the process is so simple that high-school students should be able to design woven DNA patterns, but so versatile that scientists could build complex structures for a wide variety of nanotechnology applications.

"A physicist, for example, might attach nano-sized semiconductor 'quantum dots' in a pattern that creates a quantum computer," he said. "A biologist might use DNA origami to take proteins which normally occur separately in nature, and organize them into a multi-enzyme factory that hands a chemical product from one enzyme machine to the next in the manner of an assembly line."

Rothemund's technique uses chemicals to twist a long, single-stranded DNA molecule into a predetermined shape, then "staples" the scaffolding together with crossover strands.

The nanoscale map, which sketches out both North and South America at a staggering 200-trillionths of their actual size, aims to demonstrate the precision and complexity with which DNA can be manipulated using the approach.



To make the design process less complicated, Rothemund created software that works out which short-strand sequences will generate different shapes. Rothemund says it should be possible to precisely arrange quantum dots or carbon nanotubes after chemically binding them to DNA, using the method.

William Shih at the Biomolecular Nanotechnology Group at Harvard Medical School in Boston, US, says this offers the most flexible method yet for building nanoscale structures. Shih is experimenting with the technique as a means of making molecular 3D cages, which could be used to build molecular motors.

March 14, 2006

Physical manipulation of chemistry reactions

Here is more evidence and advancing capability to physically manipulate and effect chemical reactions.

Using a chain of molecules as an infinitesimal lanyard to tug on a chemical bond about to break, Duke University chemists have found they can speed a complex chemical reaction Craig's group used an AFM tip to exert almost infinitesimally small tugs on a molecular complex made of pyridine and the metal palladium.

The researchers dangled the pyridine-palladium complex in space as if it were part of a molecular trapeze act, by attaching trapeze "wires" made of atomic chains of the molecule polyethylene glycol (PEG). One PEG chain connected the dangling pyridine-palladium to the AFM's tip. A separate PEG "wire" anchored the complex underneath onto an underlying surface substrate.

When the AFM's flexible tip pivoted upward, it pulled on the bond linking the pyridine to the palladium. "This is almost like spring-loading that bond," Craig said.

Computational chemistry - biology advance: complete virus modelled

Researchers simulate complete structure of virus -- on a computer. This is showing an advance of the power and capabilities of computational chemistry and now computational molecular biology. Better computer work can accelerate the progress of the experimental work.

The satellite virus they chose is a spherical RNA sub-viral agent that is so small and simple that it can only proliferate in a cell already hijacked by a helper virus -- in this case the tobacco mosaic virus that is a serious threat to tomato plants. A computer program was used to reverse engineer the dynamics of all atoms making up the virus and a small drop of salt water surrounding it. The virus and water contain more than a million atoms altogether.

Nanomaterials, Nanoparticles: Nanorice

Nanorice is made of non-conducting iron oxide called hematite that's covered with gold. The core size and shell thickness vary slightly but the particles are about 20 times smaller than a red blood cell. Nanoparticle's shape could improve chemical sensing, biological imaging. Nanoparticles like nanorice can be used to focus light on small regions of space. In form, nanorice is similar to nanoshells, a spherical nanoparticle Halas invented in 1998 that is currently being examined for possible applications in molecular imaging, cancer treatment, medical diagnostics and chemical sensing. Both nanorice and nanoshells are made of a non-conducting core that is covered by a metallic shell.

Halas' investigations find that nanorice possesses far greater structural tunability than nanoshells and another commonly studied optical nanoparticle, the nanorod. In fact, tests indicate that nanorice is the most sensitive surface plasmon resonance (SPR) nanosensor yet devised. The nanorice core is made of non-conducting iron oxide and the outer covering of gold. The nanorice particles described in the Nano Letters paper were about 360 nanometers long and about 80 nanometers in diameter.

Nanoscale technology: Peptides repair nerve damage. Basis of reconstructive brain surgery

Although victims of stroke and traumatic brain and spinal cord injuries sometimes recover through rehabilitation, they often have permanent disabilities, in part, because scar tissue and regulatory chemicals in the brain slow nerve growth, preventing nerve tissue from repairing itself. Now a treatment that has restored lost vision in lab animals appears to overcome these obstacles, allowing a mass of nerve cells to regrow after being cut. This is the basis of reconstructive brain surgery. researchers first cut into a brain structure that conveys signals for vision, causing the small lab animals to be blinded in one eye. They then injected a clear fluid containing chains of amino acids into the damaged area. Once in the environment of the brain, these chains, called peptides, bind to one another, assembling into nano-scale fibers that bridge the gap left by the damage. The mesh of fibers prevents scar tissue from forming and may also encourage cell growth (the researchers are still investigating the mechanisms involved).

As a result, nerve cells restored severed connections, allowing 75 percent of the animals to see well enough to detect and turn toward food. The treatment restored around 30,000 nerve connections, compared with 25-30 connections made possible in other experimental treatments, Ellis-Behnke says. The treatment overcomes key obstacles to the healing of nerve tissue in stroke and traumatic brain and spinal cord injury.

March 13, 2006

Other tech: bio weapons

The MIT technology review discusses biological weapons Serguei Popov, a former Soviet bioweaponeer, claims that the soviets were successful making bioweapons that could alter behavior, and they investigated using pathogens to induce memory loss, depression, or fear. Plus they had bioweapons that could cause brain damage, paralysis, and nearly 100 percent mortality resulted. It is claimed that some of what the Soviet bioweaponeers did with difficulty and expense can now be done easily and cheaply. And all of what they accomplished can be duplicated with time and money.

How actually difficult is it? How much does new technology make it easier? New technology such as molecular nanotechnology will clearly provide a leap in the level of control over biology. Advances in biotech alone are changing the situation. It is clearly not getting harder or more expensive.

Fear, emotions and behavior have biological and chemical basis. Change and control those factors and you can effect behavior. Steroid rage is an unintended byproduct. LSD, heroin and other drugs effect behavior and perception.
If you were trying to cause a particular change, it seems reasonable that you could.