Science

DIY science is the perfect way to use your creative skills and learn something new. With the right supplies, some determination, and a curious mind, you can create amazing experiments that open up a whole world of possibilities. At home-made laboratories or tech workshops, makers from all backgrounds can explore new ideas by finding ways to study their environment in novel ways – allowing them to make breathtaking discoveries!

You can be identified by the germs you leave behind

A study by Noah Fierer and co-workers at the University of Colorado at Boulder suggests that the mix of bacterial flora each of us leaves behind on, say, our computer keyboard or mouse, may be sufficiently unique to identify us:

“Each one of us leaves a unique trail of bugs behind as we travel through our daily lives,” said Fierer, an assistant professor in CU-Boulder’s ecology and evolutionary biology department. “While this project is still in it’s preliminary stages, we think the technique could eventually become a valuable new item in the toolbox of forensic scientists.”
The study was published March 15 in the Proceedings of the National Academy of Sciences. Co-authors on the PNAS study included Christian Lauber and Nick Zhou of CU-Boulder’s Cooperative Institute for Research in Environmental Sciences, or CIRES, Daniel McDonald of CU-Boulder’s department of chemistry and biochemistry, Stanford University Postdoctoral Researcher Elizabeth Costello and CU-Boulder chemistry and biochemistry Assistant Professor Rob Knight.

Using powerful gene-sequencing techniques, the team swabbed bacterial DNA from individual keys on three personal computers and matched them up to bacteria on the fingertips of keyboard owners, comparing the results to swabs taken from other keyboards never touched by the subjects. The bacterial DNA from the keys matched much more closely to bacteria of keyboard owners than to bacterial samples taken from random fingertips and from other keyboards, Fierer said.

Here’s the abstract for Fierer’s paper at PNAS.

Brilliant low-tech soil moisture sensor

Brilliant low-tech soil moisture sensor

Two galvanized nails set in a plug of plaster-of-Paris. That’s it. The Cheap Vegetable Gardener, who created the sensor for an automated grow box project, explains:

Technically a gypsum block measures soil water tension. When the gypsum block is dry it is not possible for electricity to pass between the probes, essentially making the probe an insulator with infinite resistance. As water is added to the problem more electrons can pass between the probes effectively reducing the amount of resistance between the problem to the point when it is fully saturated where the probe has virtually zero resistance. By using this range of values you can determine the amount of water than exists in your soil.

[via Hack a Day]

Math Monday: Math-play with your food

Math Monday: Math-play with your food

Math-play with your food By George Hart for the Museum of Mathematics Making things with your food is an age-old pastime. Here are two mathematical constructions made from crackers. This illustrates the Pythagorean Theorem for a 5-12-13 right triangle. The number of crackers in the two small squares (25+144) equals the number of crackers in […]

Happy birthday, Albert Einstein!

Einstein, who would be 131 today, needs no introduction. The foremost physicist of the 20th Century, he held a position at the Institute of Advanced Study, one of the most storied intellectual centers in the world. Nobel Prize. He published papers on such physics-related topics as molecular physics, thermodynamics, the behavior of photons, statistical mechanics, […]