Month: December 2008

Build a Spectrophotometer (Schematics included) as a DIY Project

Posted by JonathanCline – December 26, 2008

I recently ran across this published paper.  Most skunkwork types seem to buy used equipment via ebay.    This article explains how to build a spectrophotometer with schematics, illustrations, and photos.  The circuit is simple:  a photoresistor, op amp, and some mechanics for the optics.

The article even includes a Bill of Materials  (component price list); for the electronics, anyway, and it’s cheap (less than $20 for single quantities through Digikey).  The article is geared towards having undergraduate students build their own laboratory equipment as an educational exercise — and if undergrads can do it, anyone can do it (the article says that a science camp of kids aged 13 to 16 found success).

Education in Chemistry

Build your own spectrophotometer

Summary

  • Take a 100 W light bulb, a light-dependent resistor and op amp, a prism or grating in front of a slit, and a curtain – and voilà , a DIY spectrophotometer.
If you build this project or a similar one, leave a comment below.

We Make the News Headlines: “Amateurs are trying genetic engineering at home”

Posted by JonathanCline – December 25, 2008

As a nice holiday surprise for me this week, my project (Melaminometer) & a team member (Meredith L. Patterson) made it into Associated Press science news: “Amateurs are trying genetic engineering at home”.  The article is accurate, and quoted below.  For the melaminometer project, we are also collaborating with Taipei National Yang Ming University.

http://news.yahoo.com/s/ap/20081225/ap_on_sc/do_it_yourself_dna

Amateurs are trying genetic engineering at home

By MARCUS WOHLSEN, Associated Press Writer Marcus Wohlsen, Associated Press Writer – Thu Dec 25, 6:49 pm ET

Meredith L. Patterson, a computer programmer by day, conducts an experiment in Meredith L. Patterson, a computer programmer by day, conducts an experiment in the dining room of her San Francisco apartment on Thursday, Dec. 18, 2008. Patterson is among a new breed of techno rebels who want to put genetic engineering tools in the hands of anyone with a smart idea. Using homemade lab equipment and the wealth of scientific knowledge available online, these hobbyists are trying to create new life forms through genetic engineering – a field long dominated by Ph.D.s toiling in university and corporate laboratories.
(AP Photo/Noah Berger)

SAN FRANCISCO – The Apple computer was invented in a garage. Same with the Google search engine. Now, tinkerers are working at home with the basic building blocks of life itself.

Using homemade lab equipment and the wealth of scientific knowledge available online, these hobbyists are trying to create new life forms through genetic engineering — a field long dominated by Ph.D.s toiling in university and corporate laboratories.

In her San Francisco dining room lab, for example, 31-year-old computer programmer Meredith L. Patterson is trying to develop genetically altered yogurt bacteria that will glow green to signal the presence of melamine, the chemical that turned Chinese-made baby formula and pet food deadly.

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The Fundamental Problems in Open Source — What’s the Bio Fix?

Posted by JonathanCline – December 3, 2008

Synthetic biology aims to create biological parts which can be connected together to form larger functional devices, and many hope the most poplar library of parts will be “Open Source”.  Openly publishing large collections of biological parts is great, as it would rapidly accelerate engineering progress and rapidly diseminate the technology.

There’s one big drawback to open source though:  Where do you go when it doesn’t work? This is called the support issue. Presumably, there’s a “community of experts” who monitor problems and provide fixes for others. More often, though, the users themselves have to become expert, or they abandon the project.   (A secondary question is:  Who do you sue when it does something wrong? which is a question I posed in my licensing discussion.)

I recently ran across the following blog article from a popular web hosting company (bluehost.com) describing their use of Linux (properly called GNU/Linux, since Linux is only a small part of the operating system, and a tapestry of GNU software makes up more than 90% of a “Linux system”).  This web hosting company is very popular with many individuals and small companies, and it’s profitable existence owes much to open source software (although it’s reported that their servers experience unhealthy downtime).  Without open source software, the company couldn’t exist; the cost of their software would make their service very unprofitable.

The following quote is telling [1]:

“Whenever we see ANY bottleneck in the system whether it be CPU, I/O Block Device, Network Block Device, Memory, and so on we find out EXACTLY what is causing the problem. When I say we find the problem, I mean we go down to the actual code in the kernel and see exactly where the issue is. Sometimes that gives us the answer we need to the solve the problem and other times it is a bug in the kernel itself that we need to create a patch for.” (The full article is quoted below)

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