Urban Agriculture: DIY Hydroponics Shelf

December 2, 2017 | ProgressTH We have experimented with indoor gardening before. Using 30W and now 50W LED floodlights, and a wide range of grow boxes and grow shelves, the final and most efficient iteration has been our hydroponics shelf.

The original hydroponics shelf (above) used MDF panels covered with aluminium tape and a 5V fan from an old grow box experiment. The red plastic covers were 3D printed, but virtually any sort of opaque plastic can be used as a cover.

The shelf began as a steel STACKO brand heavy duty shelf we attached the MDF panels of an old DIY grow box onto, including a 5V fan for air circulation. We added an aquarium air pump to aerate the AB nutrient solution put into modified 6L plastic water bottles. Foam squares were fitted into 3D printed covers to hold the plants in place.

We managed to grow several salads' worth of greens so far, and there are now many more on the way.

3D Printed DIYbio Opensource Centrifuge

November 21, 2017 | ProgressTH Our 3D printed DIYbio centrifuge v 2.0 is operational. With version 1, we used a brushless motor used on drones which required an electronic speed controller and an Arduino microcontroller just to get it to spin. This version uses a simple 12V DC motor controlled by simply flipping a rocker switch.

A microswitch located near the cover cuts the power when the cover opens, and returns power to the motor when it is closed. It is a common safety feature found on many laboratory micro centrifuges.

Because it is much simpler and because there is a lot of extra space in the housing, a lot of expanded functions can be added later by users. While this version does not require a microcontroller of any king, there is plenty of space to add one (for timers or other functions).

Check out all the files here on Thingiverse: https://www.thingiverse.com/thing:2598206

Check out a quick video demonstration here:

For information on a simple DNA extraction protocol we've used in the past which utilizes a micro centrifuge, see here.

Gene Editing vs. Alternative Technology

November 18, 2017 | ProgressTH Ed Yong in his article, "New Zealand’s War on Rats Could Change the World," helped frame up an ongoing debate over using genetically modified organisms (GMOs) altered through gene-editing technology to eradicate pests. In this particular case, the problem is rats and other invasive predatory mammals that endanger New Zealand's native bird populations.

Yong covers proposals to introduce genes into mammalian populations to hinder their ability to reproduce. These "gene-drives" are unlike other technologies like gene therapy, which replace faulty genes in human patients to correct genetic diseases or enhance an individual's immune system to fight cancer. Unlike gene therapy where the corrected genes are not passed down to an individual's offspring, gene-drives imply that edited genes would be passed down to future generations.

A rat with a compromised reproductive system would pass those genes down to whatever offspring it managed to have. Eventually, the entire species would carry the compromised genes, its numbers would dwindle, and eventually disappear altogether.

New Zealand's invasive mammalian predator problem isn't the first case this technology has been proposed for. Companies around the world are racing to introduce similarly edited genes into mosquito populations.

Wonder Technology vs Alternatives 

Mr. Yong's article, however, did not just sell biotech to readers. An articulate and superior counterargument was presented, warning of a sort of invasive species scenario in reverse where the edited genes would "quickly and relentlessly spread," overwriting an entire population's genome, and once released would be nearly impossible to contain.