- Thumbs up for 3D bone printer
- HoloTV Images Jump off the Screen, into Tomorrow's Homes
- Projector phones: Cool app or visual pollution?
- Scientist Looks to Weaponize Ball Lightning
Thumbs up for 3D bone printer
- 07 March 2009 by Andy Coghlan
EXACT replicas of a man's thumb bones have been made for the first time using a 3D printer. The breakthrough paves the way for surgeons to replace damaged or diseased bones with identical copies built from the patients' own cells.
Weinand "grew" his replacement bones on the backs of laboratory mice, in the same way that Jay Vacanti of Massachusetts General Hospital famously grew a human ear from human cartilage cells back in 1997.
However, a surrogate mouse would normally be unnecessary, says Weinand. For example, if someone had lost a thumb, the replacement bones could be grown in situ. For now, the only options are to replace the thumb with the patient's own toe, or with bone fragments from elsewhere.
There are several steps in the new process. Firstly, you need a 3D image of the bone you want to copy. If the bone has been lost or destroyed, you can make a mirror image of its surviving twin.
This image is then fed into a 3D inkjet printer, which deposits thin layers of a pre-selected material on top of one another until a 3D object materialises.
Weinand loaded the printer with tricalcium phosphate and a type of polylactic acid - natural structural materials found in the human body. The resulting bone "scaffolds" contained thousands of tiny pores into which bone cells could settle, grow and eventually displace the biodegradable scaffold altogether.
The team extracted CD117 cells from bone marrow left over after hip-replacement operations. CD117 cells grow into primordial bone cells called osteoblasts, which the team syringed onto the bone scaffolds in a gel designed to support and nourish them. Finally, the scaffolds were sewn under the skin on the backs of mice where they grew for up to 15 weeks, until the scaffold had changed into human bone. source
My comment: That is so cool! I hope this technology gets soon approved and cheap for normal people, because it could be so useful. And that soon it would be generalised for larger organs, like hearts or even eyes. It might sound little bit ugly, to grow yourself an organ, but in the end, so many people have to live without their organs or with transplant. To make a new one is so much preferable.
Projector phones: Cool app or visual pollution?
- 25 February 2009 by Paul Marks
IF HEARING other people's music fizzing out of tinny headphones annoys you, get ready for even more irritation: chip maker Texas Instruments (TI) has shrunk a video projector to the size of a raisin and it says the device is cheap enough to become the next must-have feature for cellphones. This means people could project their photos, videos and Powerpoint-style presentations on walls, tables or just about any other surface.
But while specialists see some advantages in the technology, particularly in creating new ways to interact with cellphones, they also warn that it raises fresh privacy and security issues.
What's fuelling projection's move to the cellphone is the ongoing miniaturisation of the chips TI already uses in projection TVs. These digital light processing (DLP) chips contain thousands of electromechanical mirrors that each represent a pixel. When a pixel is to be illuminated, an electric field causes the mirror to tilt, sending light from red, green and blue LEDs in turn to a lens and then onto a screen.
Last year, TI launched the first micro-scale projector chip, which is called the DLP Pico and has a resolution of 480 by 320 pixels. That chip is now being used in pocket-sized portable projectors and was launched in a cellphone for the first time at last week's Mobile World Congress in Barcelona, Spain.
This Samsung phone lets users project an image about 1.3 metres wide. However, the device is unlikely to achieve mass adoption because of its low resolution.
So last week TI also launched a second-generation chip with a resolution of 850 by 480 pixels - the same as a DVD player. That kind of resolution is what cellphone makers have been asking for, says Frank Moizio of TI in Austin, Texas.
Despite increasing the number of mirrors from 150,000 to over 400,000, the new chip is 20 per cent smaller - making it much more practical for cellphones.
In most lighting conditions you can get a good image the size of a sheet of A4 paper, Moizio says. And power use is low enough for one battery charge to show a 2-hour movie.
"This is a promising, positive technology if used in the right context. If not, there could be a lot of visual pollution," warns Greaves. "People could screen material on a bus, say, that could be indecent - and that might even lead to the need for legislation."
Rukzio thinks that after a few initial transgressions people may self-adjust.
One privacy and security risk that must be addressed, he says, is accidental or malicious projection of somebody's personal information, such as bank details. source
My comment: Of course, people will adjust. We're not idiots. First, it's cool to be different, but when everybody is different, you realise that they don't care about your stuff more than you for theirs and everything settles. I can't wait to get one of those gadgets, but can't help but say-what movies would one watch, when you want to ban any forms of downloading. And no, I'm not gonna pay more than 0.1Euro for a movie projected on the wall by my phone. I mean for 3euro I get perfect sound, warmed and comfy cinema with great quality of the picture. You can't seriously expect me to pay the same money for something that is totally different! (and lol, on the indecent pictures-americans are such puritans)
HoloTV Images Jump off the Screen, into Tomorrow's Homes (w/Video)March 12th, 2009 By Lisa Zyga
PhysOrg.com) -- Unlike today’s biggest and most realistic LCD and plasma TVs, 3D TV screens can project images that seem to float in mid-air beyond the screen. That means, for instance, that viewers could watch basketball players dribble in front of, next to, or behind the TV screen as they go for a lay-up.
In a recent study, a team of researchers has developed a type of 3D TV system called “holoTV,” which works a bit differently than a standard holographic TV system. The holoTV system projects a video scene or animation onto a white-light screen, creating an image that appears to float in front of the screen. Viewers don’t need to wear special goggles to view the floating images, which have the appearance of volumetric images, although the system is not volumetric.
“Only holoTV and holography have continuous parallax, which means that when the observer moves his head, he can see different views without discontinuities.”
As Lunazzi explained, holography is academically defined as an object’s light wave interfering with a reference wave. However, this scheme requires the detection to have 10 times more resolution than is currently available, even to produce very small images, making holographic TV impractical for now.
In contrast, Lunazzi and his colleagues refer to their technique as holoTV, a term they adopted in 1990. Unlike holographic TV, holoTV doesn’t involve a reference wave. Instead, as in the researchers’ current holoTV system, holographic images are created from projection in a diffractive screen made by the splitting and subsequent interference of a light beam on a holographic film.
“3D images are impressive when they appear in front of a support, like ghosts which your hand goes through,” Lunazzi said. “These images are often named ‘floating images,’ which don’t require goggles. The support may be so transparent that it is not perceived.
When projecting on the screen, each wavelength of the white-light beam converges at a different position beyond the screen, so that a viewer’s left and right eyes receive light at different wavelengths (different colors), each composed of many beams converging toward the eyes. The projection makes each eye receive a different view to compose the scene as a natural one.
Using a diffraction grating, the researchers demonstrated how to project the image in front, behind, or next to the screen. The diffraction causes a blur on the screen, and the wider the blur, the greater the distance between the image and the diffraction grating - and the greater the depth of the image. One example the researchers demonstrated is an image of a man walking, which is projected 27cm in front of the screen. When sitting 140cm from the screen, a viewer would have a narrow field of view of 24cm (or 11°), enough to accommodate small head movements.
“Two or three persons can watch, in fact, if seated along a line,” Lunazzi said. “To achieve a larger angle, greater diffractive power is needed and could be obtained by larger interference angles on the recording of the screen. New materials should in fact be used to obtain higher diffraction efficiency to reduce the effect of the ambient light.” The researchers have already constructed improved screens, and plan to publish the results in upcoming papers.source
My comment: I think that recently I wrote about other 3d technology that was cooler than this, but I like the way how people think newer and newer way to use 3d. I so much love 3d movies, that's one of my ultimate funs :)
Scientist Looks to Weaponize Ball LightningBy David HamblingFebruary 20, 2009
Ball lightning has been the subject of much scientific scrutiny over the years. And, as with many powerful natural phenomena, the question arises: "Can we turn it into a weapon?" Peculiar as it may seem, that's exactly what some researchers are working on -- even though it hasn't even been properly replicated in the laboratory yet.
The exact cause and nature of ball lighting has yet to be determined; there may be several different types, confusing matters further. But generally it manifests as a grapefruit-sized sphere of light moving slowly through the air which may end by fizzling out or exploding.
In the mid-'60s, the U.S. military started exploring ways that the phenomenon might be weaponized. Take this 1965 Defense Technical Information Center report on Survey of Kugelblitz Theories For Electromagnetic Incendiaries, (Kugelblitz is German for ball lighting). The document summarizes and evaluates the ball lightning theories then prevalent, and recommends "a theoretical and experimental Kugelblitz program... as a means of developing the theory into a weapons application." This led to an Air Force program called Harness Cavalier, which seems to have ended without producing anything conclusive.
However, some years later scientist Dr. Paul Koloc was looking at methods of containing high-temperature plasma during nuclear fusion. There are many schemes for containing plasma in donut-shaped magnetic fields using a device called a Tokomak. Koloc's insight was that, under the right conditions, a donut-shaped mass of moving plasma would generate the required fields for containment itself. No Tokomak would be required for this "plasmoid," which would be completely stable and self-sustaining. It is a very close equivalent of the smoke ring -- another type of dynamic "vortex ring," which remains stable over a period of time, unlike an unstructured cloud of smoke.
Koloc also theorized that if a donut-shaped plasmoid was created accidentally -- say, during a lightning strike -- it would remain stable for a period of seconds of minutes. This he believes is the explanation for ball lightning.
In the '80s, Koloc's team succeeded in creating small, short-lived plasmoids from "chicken egg to softball" size in the laboratory. It was a good start, but not enough to convince the world that he's right about ball lightning. Ultimately the work might lead to a means of containing nuclear fusion... but there were some engineering challenges to tackle.
However, in 2002, Koloc's company, Prometheus II, briefly obtained funding from the Missile Defence Agency. The aim was to create stable 'magnetoplasmoids' a foot in diameter which would last between one and five seconds. In the subsequent phase, the magnetoplasmoid would be compressed and accelerate to two hundred kilometers a second. This "encapsulated EMP bullet" would make an idea anti-missile weapon, generating an intense electromagnetic pulse on impact which would scramble the guidance system and any electronics, as well as causing thermal damage.
Koloc called the weapon "Phased Hyper-Acceleration for Shock, EMP, and Radiation" -- PHASER.
Nothing seems to have resulted after the Phase I contract, so I contacted Koloc to see how his research had progressed. He confirmed that they had successfully formed plasmoids a foot in diameter, but that these could not be made sufficiently stable.
To make it work and overcome the stability problem, they need a device known as a "fast rising parallel plate transmission line." There was not enough funding for this and the company is still trying to raise funds.
So a ball lightning weapon remains tantalizingly out of reach –- or does it? As I noted in a previous article on military ball lightning, the USAF’s Phillips Laboratory examined a very similar concept in 1993. Again, this involved accelerating a donut-shaped mass of plasma to high speed as an anti-missile weapon in a project called Magnetically Accelerated Ring to Achieve Ultra-high Directed Energy and Radiation, or MARAUDER. Based on the Air Force's awesome Shiva Star power system, experiments spat out plasmoids at ultra-high speed that were expected to reach 3,000 kilometers a second by 1995. But nothing was published after 1993, and MARAUDER was classified, disappearing into the black world of secret programs. source
My comment:Yup, you don't know why something happens, you don't know exactly how it happens, but you're willing to use it as a weapon. Ok, I cannot like this! I don't see why people are so eager to make weapons for any form of destruction, but obviously, the military loves to fund such projects. Sure, why should we work on cold fusion, when we can fun new and fancy weapons which we would sell to our allies and watch how they kill children with them.