July 17, 2009

Current Nanoparticle for Drug Delivery and imaging

Carbon Nanotubes and Teflon Repel Hot Water

To fabricate hot water repellent fabrics, a nanocomposite of Carbon Nanotubes (CNTs) and Teflon was prepared and applied to commercial fabrics to produce scalding protection clothes. Current water repellent material only works well up to 25 °C. The new material was fairly effective for static water up to 80 °C and reduced effectiveness for dynamic water.

The repellency of the CNTs–Teflon treated fabrics to hot beverages (water, milk, coffee and tea, 50–80 °C) was studied. The spray test shows that although some superhydrophobic surfaces exhibit high repellency to static water they show reduced repellency to dynamic water.

'further work would be needed to repeat these tests and verify the mechanism.' Liu acknowledges that 'the creation of superhydrophobic surfaces which can repel pressured hot liquids is still a great challenge to scientists.'

Aubrey de Grey Interview by Sander Olson

Aubrey de Grey: Founder of Strategies for Engineered Negligible Senescence

Strategies for Engineered Negligible Senescence (SENS) is a 25-year long research strategy, currently underway, to develop a regenerative medical procedure to periodically repair all the age-related damage in the human body, thereby maintaining a youth-like state indefinitely

Question: Tell us about the SENS foundation. What is its budget? How many research projects does it currently have underway?

Answer: SENS Foundation was created in April 2009 and took over the SENS research activities of the Methuselah Foundation (MF). We have a very limited budget at this point, initially consisting of the funds that had been donated to the MF for SENS research and had not already been spent. In essence we currently have a freeze on funding anything new right now. However, we are of course working extremely hard to change that!

Question: Many of your strategies toward Strategies for Engineered Negligible Senescence (SENS) entail finding potent enzymes that degrade various molecules. How many new and useful enzymes have been discovered by the SENS foundation so far?

Answer: We've identified several enzymes that degrade each of two major "waste products" whose accumulation underlies major age-related diseases: 7-ketocholesterol, which many researchers have concluded is the most potent cause of atherosclerosis, and A2E, which has the corresponding status in respect of age-related macular degeneration.

Question: Many of the problems from ageing result from degradations in the mitochondria. Can your strategy of placing mitochondrial genes in the cell nucleus truly render the mitochondria redundant?

Answer: It certainly wouldn't render the mitochondria redundant, no - but it would render the mitochondrial DNA (mtDNA) redundant. The purpose of this therapy is to ensure that the 13 proteins encoded by the mtDNA are present in mitochondria even if the mtDNA has suffered mutations.

Question: How does SENS deal with the buildup of toxins in the body, such as heavy metals, that cannot be broken down by any enzyme?

Answer: Inorganic toxins indeed accumulate in the body, but actually there are already systems for excreting them: it's just that those systems become increasingly ineffective as a result of other changes (changes that SENS addresses directly). A good example is fat tissue. when fat is lost, heavy metals are released into the circulation - and this is actually one reason not to lose weight too rapidly. Once in the circulation, some metals are reabsorbed, but a lot is excreted.

Question: To what extent does SENS research overlap with more conventional medical research, such as gene therapy?

Answer: Well, a lot of people would hesitate to call gene therapy conventional! But SENS will certainly utilize gene therapy extensively.

Question: How much research is the SENS foundation performing on stem cells?

Answer: Basically none - and this is for a very simple reason, namely that we need to conserve our modest resources for those areas of SENS that are not being adequately pursued independently of us. Stem cell treatments will undoubtedly form a large part of the eventual SENS panel of therapies, but for the foreseeable future they'll be quite adequately advanced by others.

Question: Of the "seven deadly things" that cause ageing - cell loss, mutant mitochondria, mutations, death-resistant cells, tissue stiffening, and extracellular and intracellular aggregates - which will be the most difficult to address?

Answer: I'm in no doubt that the hardest one to address is mutations in our chromosomes. The problem with those is that they lead to cancer, which has natural selection at its disposal - so the cleverer we get, the cleverer it gets. That's why the SENS approach to combating such mutations is so aggressive, and indeed so ambitious.

Question: Is the mainstream scientific establishment becoming more receptive to your research and arguments?

Answer: Definitely. The derision that they previously met within most of the biogerontology community has become very much a minority view, as it's become more obvious that there is no scientific basis for dismissing SENS. The process has also been aided by the enthusiastic acceptance of the various SENS concepts by those whose work is most relevant to their development - researchers who are mostly not biogerontologists.

Question: What institutions currently fund your research? To what extent is your research constrained by insufficient funding?

Answer: Our research is not funded by any institutions (such as NIH), only by philanthropy. Its rate is massively constrained by insufficient funding: we could certainly spend 50 times what we currently have before we came close to running out of important projects to support.

Question: The Wyeth corporation recently unveiled a chemical called rapamune that increased mice lifespans by up to 14%. What is your assessment of rapamune's potential?

Answer: I think rapamune's potential resembles that of other interventions that have done well on mice: I don't expect them to work nearly so well in humans. That's basically because they "tune" the recipient's existing metabolism, and the selective pressure to maintain "tunability" of one's metabolic pathways is lower with longer-lived species. For humans we're going to need bona fide repair and maintenance.

Question: How has your view of ageing and SENS changed during the past decade? Are you more or are you less optimistic about SENS prospects than a decade ago?

Answer: My views have changed very little since I came up with SENS in 2000. It remains clear to me that SENS is on the right track, and my estimate of the required timeframe for its implementation (subject to funding, as always) is also little changed.

Question: How many researchers at your institute are actively involved in anti-ageing research? How many individuals are engaged in this type of research worldwide?

Answer: The answer to that question depends on your definition of "anti-aging research". Most biogerontology research is of highly questionable relevance to the postponement of aging - though of course any basic research can always stumble upon useful tricks. Conversely, lots of biomedical research that is not being done for the purpose of combating aging is in fact highly likely to contribute to eventual anti-aging therapies. With those considerations in mind, I would say that there are at least a few thousand people working in relevant areas, most of them in stem cell research.

Question: Could you tell us more about your Atherosclerosis, immunosenescence, and macular degeneration programs? How rapidly are these programs progressing?

Answer: I mentioned the atherosclerosis and macular degeneration work earlier. We're very happy about progress, as shown by the identification of these enzymes (and the publication of our results in prestigious journals), but of course there's a very long way to go. The immunosenescence program is at a much earlier stage, having begun only this past October, and it won't deliver even preliminary results for several months yet, but we're very optimistic about the project.

Question: You are currently 46. What do you consider the likelihood of your surviving to 150?

Answer: Around 50%. However, if I do, I reckon I'll have at least a 50% chance of then making it to 1000. But let's remember; that's not the object of this research. The object is to stop people getting sick, and the only thing that distinguishes SENS from other medicine for the elderly is that there's a good chance that SENS can keep people healthy so well that there will be the side-benefit of radically longer lives.

Nanophotonic on a Chip Advance

On Arvix there is a possible breakthrough nanophotonic research paper from the University of Southampton: The light-well: A tuneable free-electron light source on a chip. H/T MIT Technology Review

The passage of a free-electron beam through a nano-hole in a periodically layered metal/dielectric structure creates a new type of tuneable, nanoscale radiation source - a ‘light-well’. With a lateral size of just a few hundred nanometers, and an emission intensity of 200 W/cm2 such light-wells may be employed in nanophotonic circuits as chip-scale sources, or in densely packed ensembles for optical memory and display applications.

We provide the first proof-of-concept demonstration of a tuneable, electron-beam-driven, nanoscale radiation source in which light is generated as free-electrons travel down a ‘light-well’ - a nano-hole through a stack of alternating metal and dielectric layers. Near-infrared emission is demonstrated in the present case but the concept may readily be scaled to other wavelength ranges by varying the periodicity of the structure. The simplicity and nanoscale dimensions of the lightwell geometry make it a potentially important device for future integrated nanophotonic circuit, optical memory and display applications where it may be driven by the kinds of microscopic electron sources already developed for ultrahigh-frequency nanoelectronics and next generation flat-panel displays

July 16, 2009

Beyond Molecular Nanotechnology is Femtotech : Proposal for Synthesizing Degenerate Matter

A 14 page pdf has been released by Professor Bolonkin Femtotechnology: Nuclear Matter with Fantastic Properties A lot of the paper is discussing what amazing things would be possible if it could be done. The key part is what is trying to be accomplished and the beginnings of how. We are talking about customized atomic nucleus strings and other shapes. The power of what would be possible is huge. But first what most would consider that impossible first step.

The form of matter containing and subsuming all the atom’s particles [from nucleons (neutrons, protons), electrons and other nuclear particles] into the nucleus is named degenerate matter. Degenerate matter found in white dwarfs, neutron stars and black holes. Conventionally this matter in such large astronomical objects has a high temperature (as independent particles!) and a high gravity adding a forcing, confining pressure in a very massive celestial objects. In nature, degenerate matter exists stably (as a big lump) to our knowledge only in large astronomical masses (include their surface where gravitation pressure is zero) and into big nuclei of conventional matter. Our purpose is to design artificial small masses of synthetic degenerate matter in form of an extremely thin strong thread (fiber, filament, string), round bar (rod), tube, net (dense or non dense weave and mesh size) which can exist at Earth-normal temperatures and pressures. Note that such stabilized degenerate matter in small amounts does not exist in Nature as far as we know. Therefore I have named this matter AB-Matter.

UPDATE: There is conventional work probing atomic nucleus and knocking out protons and neutrons and there is some natural percentage of pairing up of the particles.

One method of producing AB-Matter may use the technology reminiscent of computer chips.

One side of closed box 1 is evaporation mask 2. In the other size are located the sources of neutrons, charged nuclear particles (protons, charged nuclei and their connections) and electrons. Sources (guns) of charged particles have accelerators of particles and control their energy and direction. They concentrate (focus) particles, send particles (in beam form) to needed points with needed energy for overcoming the Coulomb barrier. The needed neutrons are received also from nuclear reactions and reflected by the containing walls.

Various other means are under consideration for generation of AB-Matter, what is certain however is that once the first small amounts have been achieved, larger and larger amounts will be produced with ever increasing ease. Consider for example, that once we have achieved the ability to make a solid AB-Matter film (a sliced plane through a solid block of AB-matter) and then developed the ability to place holes with precision through it one nucleon wide, a modified extrusion technique may produce AB-Matter strings (thin fiber), by passage of conventional matter in gas, liquid or solid state through the AB-Matter matrix (mask). This would be a ‘femto-die’ as Joseph Friedlander of Shave Shomron, Israel, has labeled it. Re-assembling these strings with perfect precision and alignment would produce more AB-matter film; leaving deliberate gaps would reproduce the ‘holes’ in the initial ‘femto-die’.

The developing of femtotechnology is easier, in one sense, than the developing of fully controllable nanotechnology because we have only three main particles (protons, neutrons, their ready combination of nuclei 2D, 3T, 4He and electrons) as construction material and developed methods of their energy control, focusing and direction.

July 15, 2009

China has 100 million Electric Bikes

Time Magazine has an update: There are 100 million electric bikes in China

Last year (2008) Chinese bought about 90% of the 23 million e-bikes sold worldwide. Experts say that next regions to likely embrace e-bikes are Southeast Asia, where gas-powered scooters are popular, and India, where rising incomes mean personal transportation is starting to be in reach of hundreds of millions. Japan has seen steady annual sales of about 300,000 for several years, and in the cycle-crazy Netherlands e-bikes are beginning to take off. In the U.S., where bikes are still overwhelmingly used for recreation rather than transportation, e-bike sales are expected to break 200,000 this year, or about 1% of China's sales.

* Typical e-bikes in China have 100 km on a full charge
* official top speed is 12mph but many go 30 mph
* Typical e-bikes in China cost 2000 RMB (USD290)
* In 2006 there were 2,700 licensed manufacturers, and countless additional smaller shops
* Leading manufacturer Xinri makes 1.6 million e-bikes per year

Motorcycles are too dangerous, cars are too expensive, public transportation is too crowded and pedal bikes leave you too tired

Higher Power Nanocrystalline Core Electric Bike Motor from Texas

The device is an electric motor with a nano-crystalline core. It is the size of a casserole dish, and more powerful than a 600cc motorcycle engine. Okonsky’s company, KLD Energy, is supplying the motor to the Vietnamese motorbike company Sufat and by the end of the year he expects to startle Hanoi with something it has never seen before — a clean, quiet electric scooter that can accelerate from zero to 60 miles per hour in under 10 seconds.

The main difference, though, is that KLD’s electric motors are simply much stronger than those on traditional electric scooters, because they use a different technology. Electric motors work by alternating the polarity of several magnets back and forth, causing a rotor to spin. Most materials release heat each time their polarity shifts, and if the frequency of alternation goes too high, the motor will overheat.

But the nano-crystalline material at the core of a KLD motor scarcely heats up when its polarity shifts. That means the motor can alternate much faster, generating more power. The KLD motor is so strong and so small that it doesn’t need a drivetrain, or gears. It is simply built into the motorbike’s rear wheel, which it turns directly, like pedaling a unicycle. Eliminating the drivetrain saves energy and improves reliability — there are fewer parts to break down.

The new bikes are slated to sell for between $1,500 and $2,000 U.S. dollars. That’s a reasonable price in the Vietnamese market; a mid-range Honda Future gas-powered bike sells for $1,700, while more chic bikes, such as the Piaggio Honda SH, sell for $4,000 or more.

KLD Energy Technology's nanocrystalline core electric motor

The high-performance motor system's technology innovates in several key areas to drive performance:

* With a high-frequency to low RPM ratio, the motor system does not require a transmission.
* Through the use of an innovative nano-crystalline composite material the motor conducts energy ten times more efficiently than traditional iron-core motors, eliminating the need for additional cooling mechanisms and enabling greater responsiveness.
* As a result of the more efficient material used to build the motor, it can achieve 2500 hertz, outperforming traditional motors' 250 hertz average.
* The system's computerized motor controller is designed specifically to perform and respond to the higher-frequency output of the motor

E-140 Max Speed - 40 mph (80 km/h) Range - 160 km (100 mi) and the E-165: Max Speed - 65 mph (100 km/h)
Range - 160 km (100 mi)

KLD scooters go for about $2,000 in Vietnam. The scooters headed to America will feature lithiumion batteries and cost $3,288. That is about $5,000 less than the VX-1E by Vetrix, an electric scooter of similar size and ability.

China's Electric Bike Success

Government regulations limit the top speed of e-bikes to about 12 mph. But manufacturers are building bigger and bigger machines with speed regulators that are easily removed. E-bikes that are basically pedal-powered machines with an electric boost are common in cities like Beijing and Shanghai, but e-scooters with heavier motors and top speeds of around 30 mph, fast enough to rival mopeds, are growing in popularity.

Major Chinese cities have extensive bicycle lanes, which means riders can avoid the worst of rush-hour congestion. In cities such as Shanghai, local governments have drastically raised licensing fees on gas-powered scooters in recent years, effectively driving hoards of consumers to e-bike manufacturers.

There were 500 million regular bicycle riders so there is a conversion of regular bikers to e-bike riders.

Seeking Alpha has an analysis of the neodymium magnets used in the electric bikes.

The electric bikes (EBs) contain lightweight, compact, NdFeB [Neodymium-Iron-Boron] magnets for their miniature motors. They use approximately 350grams of NdFeB per bicycle. The chemical formula is (Nd-2-Fe-14-B) so this yields 86g Nd/EB. In 2007, EBs accounted for 5800 tons NdFeB or 13% of the worldwide total. I don't have figures for the neodymium produced in 2008 but if it was the same as 2007, the share would have increased to 18%. The average growth rate for the past 8 years was 35%. If this continues then by 2014 Chinese demand would be 100 million/year or 35000 tons NdFeB.

There does not appear to be an alternative to NdFeB in bicycles due to space and weight considerations. The price of NdFeB magnets are about $40/kg so the bicycle contains $14 of magnets and $1.70 of Nd @ current $20/kg.Nd. EBs retail @ $290 and neodymium represents 0.6% of that.

Hybrid Cars

A hybrid car's electric motor can be up to 100kW although 55kW is a reasonable figure. For a 55kW motor 0.65kg of Nd-Dy-Co-Fe-B is required which gives 200g Nd/Motor (3.6g/kW) and 30g Dy/Motor (0.55g/kW). A 25kW generator is typically required to recoup braking energy so for analysis purposes a hybrid vehicle contains 288g Nd and 44g Dy. At $20/kg a car contains $5.76 worth of Nd and at $110/kg Dy a car contains $4.84 worth of Dy. At $10.60 worth of REs per car and a selling price of, say, $20,000, REs represent 0.05% of sticker price.

Light Electric Motors
According to the blue paper on China's auto industry in 2009, the number of electric bicycles and electric motors has reached about 50 million, which accounts for 90% of the world total.

One of the targets set by the national plan on industrial adjustment and revitalization of China's auto industry released in March, 2009 specifies that by 2011, China will have developed the production capacity of 500,000 new energy auto vehicles, including pure electric vehicles, plug-in hybrid vehicles and mixed power-driven vehicles

Nearest Enhancements - Better Gear, Clothes and Nutrients

Neutraceuticals for longevity are not released yet, but will be released soon according to Gregory Benford at his presentation at the Covergence conference of last year.

Video here

Genescient is testing a longevity product in Bangalore later in 2009.

Genescient’s first longevity product — to be ready for human trials later this year — will be tested at a laboratory in Bangalore. Genescient’s patent advisor also is an Indian.

The company uses directed evolution techniques — molecular biology methods that mimic natural evolution in laboratory conditions — to produce long-lived animals. The genomics of these animals are used to find critical pathways to longevity. “Using those, we find substances, some from traditional Indian medicine, interestingly, to devise pills to enhance the longevity pathways we already have. Those are our first products — arrived at by further testing on animals, to be sure they work and have no bad side effects,” he says.

The other aspect is that fixing micronutrient deficiency will probably prevent our lives from being shorter and less healthy.

Gear Enhancement

The iphone sniper buddy

Wired discusses using exercise monitoring devices that link to iPhones and iPods that are being used to improve workouts and to help people get better results. The help is better motivation and by using the tracking information to make better workouts. 10% improvement in Gym retention. Nike has 1.5 million people tracking their workouts and they claim the data helps motivate people to exercise more.

5 Exercise Tools

Garmin Forerunner 310XT
Garmin's latest GPS watch uses wireless ANT+ and networking to send data straight to your desktop. Plus, it's waterproof, so you can splish-splash without a crash.
$350, garmin.com

Training Peaks 3.0
Training Peaks sucks up data from dozens of fitness devices and reports back with visualizations of heart rate, power output, speed, distance, elevation, and much more.
$119/year, trainingpeaks.com

RunKeeper Pro
Turn your iPhone into a mobile fitness center. Using the GPS chip in 3G iPhones, this app tracks speed and distance and lets you upload and share your routes on the company's site.
$10, runkeeper.com

Performance monitoring meets Web 2.0 trash talk. This social network not only logs your data, it also shows your friends' numbers so you can "comment" on their workouts.
$20/year, weendure.com

SMHeart Link
This little gadget syncs with your favorite exercise gear — heart rate monitors, power meters, even fitness equipment — and sends the data back to your iPhone or iPod Touch wirelessly.
$125, smheartlink.com

Future Wearable and Super Gear Enhancement

Here is a longer version of my theory of wearable enhancement.

Things like the iphone and electronics or performance enhancing clothes (like the olympic swimsuit) are going to make more rapid progress. They will have a less regulatory delays to distribution.

Key enabling features:
* Always on (needs lower power usage and efficiency)
* Always available (no bootup delays)
* Always in context
- gathering info from passive sensors means devices are ready to be triggered or will auto trigger
- lot of universal memory means no context switching delays
* Vastly increased array of very cheap and very effective sensors
* Personal LADAR (laser radar, which is key device for enable self driving robot cars)
* More on chip devices (on chip super accurate atomic clocks which enables more accurate GPS
* Power harvestors

The vision is not iron man but flexible elextronics and carbon/polymer and suit man with a super network of gadgets and tiny and cheap sensors.

Wearable workstations with heads up display goggles

There are exoskeletons and those will become less rare, but the number of people who will have superdevices like an goggle display- iPhone 8.0 or competing gear will be hundreds of millions when the number of exoskeletons will be trying to get to the first million deployments. Many of the iPhone 8.0 person will have some in-clothing electronics and some performance enhancing clothing from Nike.

SpaceX Successfully Delivers Their First Commercial Satellite

July 14, 2009

Fabric Cameras and Electronics

Imagine a soldier's uniform made of a special fabric that allows him to look in all directions and identify threats that are to his side or even behind him. In work that could turn such science fiction into reality, MIT researchers have developed light-detecting fibers that, when weaved into a web, act as a flexible camera. Fabric composed of these fibers could be joined to a computer that could provide information on a small display screen attached to a visor, providing the soldier greater awareness of his surroundings.

This is the first time that anybody has demonstrated that a single plane of fibers, or 'fabric,' can collect images just like a camera but without a lens.

The team starts with a macroscopic cylinder, or preform, of these elements. That preform is placed into a special furnace that melts the components, carefully drawing them into miniscule fibers that retain the original orientation of the various layers. The process can produce many meters of fiber.

Fink's team demonstrated the power of their approach by placing an object - a smiley face - between a light source and a small swatch of fabric composed of the fibers that was in turn connected to an external amplifying electrical circuit and computer.

The individual fibers measure the intensity of the light illuminating them and convert it to an electrical signal. Importantly, they are also designed to differentiate between light at different wavelengths or colors. A mesh of fibers is then deployed to measure light intensity distribution at different wavelengths across a large area.

In the current work, the smiley face was illuminated with light at two separate wavelengths. This generated a distinct pattern on the fabric mesh that was then fed into a computer. From there, an algorithm described earlier by the Fink team in Nature Materials assimilates the data to create a black-and-white image of the object on a computer screen.

First author Fabien Sorin, a postdoctoral associate in RLE, DMSE and ISN, said that as the individual fibers become more sophisticated, it is possible to envision fabrics with more intriguing and complex functionalities, such as ones capable of producing crisper images in color.

Abstract: Exploiting Collective Effects of Multiple Optoelectronic Devices Integrated in a Single Fiber

The opportunities and challenges of realizing sophisticated functionality by assembling many nanoscale devices, while covering large areas, remain for the most part unrealized and unresolved. In this work, we demonstrate the successful fabrication of an eight-device cascaded optoelectronic fiber structure in which components down to 100 nm are individually electrically addressed and can operate collectively to deliver novel functionality over large area coverage. We show that a tandem arrangement of subwavelength photodetecting devices integrated in a single fiber enables the extraction of information on the direction, wavelength, and potentially even color of incident radiation over a wide spectral range in the visible regime. Finally, we fabricated a 0.1 square meter single plane fiber assembly which uses polychromatic illumination to extract images without the use of a lens, representing an important step toward ambient light imaging fabrics.

E-Bike: Boost Muscle Power 50 Times for 50 mph Bike

The Erokit electric bicycle built by Stefan Gulas was introduced in Germany. The name is pronounced "e rocket". The 220 pound bike reaches a top speed of 50 mph and seems to get there fast watching this video where the rider is set to pass a car moving at a decent clip. It can be yours for 33,000 euro (about $45,000 USD). eROCKIT electronics monitoring the driver's muscular effort and multiplying it by a factor of up to 50.

The electrically driven eROCKIT is best described as the alignment of two extremely different characteristics. Conventional handling that is familiar to everyone, coupled with a highly innovative and revolutionary propulsion system.

Everything about eROCKIT’s general handling comes from the common bicycle. From using the pedals to accelerate and ride the vehicle, to the rear and front wheel brakes, whose handles are positioned in natural locations on the left and right handlebars.

The revolutionary propulsion system is based on muscle force multiplication and delivers comparable power to a regular motorcycle. This is possible due to the proprietary eROCKIT electronics monitoring the driver's muscular effort and multiplying it by a factor of up to 50. The multiplied force is then transmitted to the rear wheel propelling the eROCKIT to a top speed of up to 80 kph (50 mph).

July 13, 2009

Fast Forward Radio Tuesday, July 14, 2009

A panel of futurists, including Brian Wang of Next Big Future, will discuss how and why people are going to be making major enhancements to themselves, and soon on Fast Forward Radio. This will be part 4 of the World Transformed Series by the Speculist blog.

We're all familiar with enhancements intended to make us stronger or to look younger or more beautiful, but those hardly scratch the surface. Are you ready for technologies that can make us truly younger, stronger, smarter?

How about rebuilding the human machinery from the ground-up? Need longer legs? An extra hand? Eyes literally in the back of your head?

Who wants feathers? Wings? Gills?

Or maybe you're tired of having your computer do all the thinking for you. Are you ready to become the computer yourself?

From the highly desirable to the downright disturbing, we explore arguments for and against, benefits and risks, and the inevitability of re-working the human architecture.

The Guest Panelists

RU Sirius is the man who shows us where cyberculture and counterculture meet. He is a writer, talk show host, musician, and the editor of H+ magazine.

George Dvorsky is a transhumanist futurist who serves on the board of directors for Humanity+ and the Institute for Ethics and Emerging Technologies. He blogs at Sentient Developments, where he provides speculations on the future of intelligent life.

Brian Wang is a futurist who blogs about all things future-related at NextBigFuture. He is the Director of Research for the Lifeboat Foundation and a member of the Center for Responsible Nanotechnology Task Force.

The Speculist talks about enhancement in a recent article.

Improved DNA Sorting of Carbon Nanotubes

a, A 2D DNA sheet structure formed by three anti-parallel ATTTATTT strands. The dotted lines between bases indicate hydrogen bonds. The open arrow in each strand denotes 5' to 3' direction. The dashed grey arrow (top right to bottom left) represents the roll-up vector along which the DNA barrel in b is formed. b, A DNA barrel on a (8,4) nanotube formed by rolling up a 2D DNA sheet composed of two hydrogen-bonded anti-parallel ATTTATTTATTT strands. c, The structure in b viewed along the tube axis. Colour coding: orange, thymine; green, adenine; yellow ribbons, backbones

In the Journal Nature, DNA sequence motifs for structure-specific recognition and separation of carbon nanotubes

Single-walled carbon nanotubes (SWNTs) are a family of molecules that have the same cylindrical shape but different chiralities. Many fundamental studies and technological applications of SWNTs require a population of tubes with identical chirality that current syntheses cannot provide. The SWNT sorting problem—that is, separation of a synthetic mixture of tubes into individual single-chirality components—has attracted considerable attention in recent years. Intense efforts so far have focused largely on, and resulted in solutions for, a weaker version of the sorting problem: metal/semiconductor separation. A systematic and general method to purify each and every single-chirality species of the same electronic type from the synthetic mixture of SWNTs is highly desirable, but the task has proven to be insurmountable to date. Here we report such a method, which allows purification of all 12 major single-chirality semiconducting species from a synthetic mixture, with sufficient yield for both fundamental studies and application development. We have designed an effective search of a DNA library of 10^60 in size, and have identified more than 20 short DNA sequences, each of which recognizes and enables chromatographic purification of a particular nanotube species from the synthetic mixture. Recognition sequences exhibit a periodic purine–pyrimidines pattern, which can undergo hydrogen-bonding to form a two-dimensional sheet, and fold selectively on nanotubes into a well-ordered three-dimensional barrel. We propose that the ordered two-dimensional sheet and three-dimensional barrel provide the structural basis for the observed DNA recognition of SWNTs.

Eric Drexler's Comments on the Potential

DuPont group reports the development of a new method for separation [of carbon nanotubes], one that also has implications for how SNCWs could be used in atomically precise nanosystems.

SNCWs can be regarded as tubes of graphene, but these tubes can differ both in radius and in the angle between the tube’s axis and the lattice axes of the graphene sheet*. Different structures are metallic, insulating, or semiconducting, and not functionally interchangeable. Building on previous work that showed how single-strand DNA could wrap and solubilize CWNTs [Carbon MultiWall Nanotubes], the DuPont group searched the vast, combinatorial space of DNA sequences for those that would wrap tubes in an orderly and selective way that enables different kinds to be separated.

The results are surprisingly effective, enabling the separation of a dozen kinds of tubes of similar diameter, each to a purity of 60–90% or better. Each kind is preferentially wrapped by a different DNA sequence.

There are two basic strategies for getting atomically precise structures: either make them precisely, or make a mixture of kinds, and separate them. Precise CWNTs are increasingly available by means of the second strategy. Further, the ability to wrap them in well-organized sheaths of engineered biomolecules provides a natural way to interface them to complex biomolecular nanosystems.

13 Page supplemental article pdf

Manchester Report - Climate Change Solutions and Thorium Nuclear Reactors

Carnival of Space 111

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