Printing Organs With A 3D Printer

[Jordan Miller], [Christopher Chen], and a whole bunch of other researchers at the department of bioengineering at U Penn have figured out a way to print 3D tissues using a 3D printer. In this case, a RepRap modified to print sugar.

Traditional means of constructing living 3D tissues face a problem – in a living body, there’s a whole bunch of vasculature sending Oxygen and nutrients to the interior cells. In vitro, these nutrients can’t get to the cells in the core of a mass of tissue. [Jordan], [Chris], et al. solved this problem by printing a three-dimensional sugar lattice. After encasing this lattice in a gel embedded with living cells, the sugar can be dissolved and the nutrients pumped through the now hollow capillaries in the gel.

If you have access to Nature, the full text article is available here. There’s also a great video showing off this technique after the break.

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Getting A Console And Quake II Running On A Raspberry Pi

Those Raspberry Pi boards are flying into the mailboxes of tinkerers all around the globe, so our tip line is currently awash in a deluge of Raspi hacks. Here’s two that came in over the weekend:

First up is [reefab]’s port of Quake II for the Raspberry Pi. The build is based of Yamagi Quake II and is mostly playable. The Quake III port for the Raspberry Pi is old hat, but we’re happy to relive the pulse-pounding action of Quake II any day.

Next up is [Joonas]’ take on getting a serial console up and running with the Raspi. The Raspberry Pi has a UART serial console on its 26-pin header, but you can’t just connect those pins to a serial port. To shift the +/- 12V down to the 3.3 Volts the Raspi can understand, [Joonas] used a MAX3232 – the 3.3 Volt version of everyone’s favorite RS-232 transceiver. With a breadboard and a couple of caps, it’s easy to connect your Raspi to a serial console. Neat.

Open Source Synth Sounds Awesome

A little bird sent in a tip about a really cool MIDI synth. It’s called the Ambika, and it seems like just the thing to introduce a synth head to the world of soldering.

Compared to an entry-level synthesizer like the microKorg or its ilk, the Ambika is packed full of really cool features that just happen to sound awesome. In addition to the basic saw, square, and sine waves, there is also FM, and wavetable synthesis along with a noise generator, rudimentary voice synth, and a bitcrushed sawtooth wave voice. Really, the sound demos (available after the break) speak for themselves.

The hardware is based on the ATMega644p, a fairly high-powered 8-bit microprocessor notably used in the Sanguino. This synth supports up to 6 voices, each individual voice is contained on a separate circuit board attached to the motherboard.

Of course, the schematics/board files/firmware for the Ambika are freely available along with a pretty amazing set of technical notes. There’s no word on how much the Ambika will cost, but having it available as a kit should make it palatable if you don’t mind spending a Saturday holding an iron.

Tip ‘o the hat to an anon for sending this one in.

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