Year: 2012

What Causes Autism?

Martha Herbert argues that diet and environmental toxins play a significant role in creating autism in an interview with Anne Strainchamps on To the Best Of Our Knowledge.

After much thought, I have come to the formulation that autism may be most comprehensively understood and helped through an inclusive whole-body systems approach, where genes and environment are understood to interplay.

— from Martha Herbert’s Website.

Herbert is the author of The Autism Revolution, and her website also hosts her scientific publications.

The Real-Time ITCZ

NOAA provides real-time (at least in the last 6 hours) images of the tropical Atlantic, which will often show the Inter-Tropical Convergence Zone (ITCZ) quite nicely.

They show images captured using visible light:

Tropical Atlantic using visible light. (ᔥEUMETSAT, ↬NOAA)

As well as infra-red:

Tropical Atlantic using visible light. (ᔥEUMETSAT, ↬NOAA)

Octave Sound Samples

I’ve not had much real musical training, but enough to know that I have a terrible ear for sound and can’t reproduce a note for anything. However, an informed source tells me that octaves represent the same note at different pitches.

The pitch is the frequency of the sound wave.

This "note" is a sound wave with a frequency (pitch) of 347 cycles per second (347 Hz), which has a wavelength of approximately 1 meter. It sounds like this.

If one note has twice the frequency of the other, they’re said to be one octave apart. For example, click on the image below to listen to the same note at different octaves:

Click the waves to hear the different octaves. The wavelengths of the sounds are shown (in meters).

Or play the files:

Wavelength Frequency Sound File (mp3)
1 m 347 Hz 1m.mpg
0.5 m 694 Hz 50cm.mp3
0.25 m 1388 Hz 25cm.mp3

Foraging for Food

The Splendid Table has an enticing interview with Hank Shaw who just wrote a book on foraging for food in the woods and how to cook what you find. The book’s called, “Hunt, Gather, Cook“.

Shaw’s website is full of details about his adventures in foraging, as well as a lot of recipes — including some excellent photographs of the work in progress.

Why We Need to Sleep

Sleep patterns change during adolescence, but unless you can alter the school day, students need to figure out ways to deal with their predilection for going to bed and waking up late. Jason at FrugalDad has a nice compilation of statistics about why we need sleep. Particularly useful is the section on different ways to get more sleep. (I also like the fact that he cites his sources at the bottom.)

sleep

Source: ᔥhttp://frugaldad.com

How Black? 99.7% Black

One of my students asked, “How black can you get?” I didn’t know the answer; however, serendipitously, I ran into this article last night. Researchers in Rochester, NY have created a solar cell that absorbs 99.7% of incoming light, which means that it has an albedo (reflectivity) of just 0.3%. Since solar cells create energy by absorbing light, the more light it can absorb — the blacker the solar cell — the more efficient the solar cell is likely to be.

Expectations of Math

Jonathan Wai wonders, “Why Is It Socially Acceptable To Be Bad At Math?” After all, it’s not socially acceptable to be illiterate.

The cultural norm that it’s okay to be bad at math has deleterious effects on student motivation. I’ve seen it myself. One parent of an excellent, hard-working student confessed that it was probably her talking about how bad she was at math that helped her kid feel like they didn’t need to work that hard at the subject; especially since the student didn’t think that they were going to use the math anyway.

Some think that the solution is to use a more integrated curriculum and teach, “a math curriculum that focused on real-life problems,”:

Imagine replacing the sequence of algebra, geometry and calculus with a sequence of finance, data and basic engineering. In the finance course, students would learn the exponential function, use formulas in spreadsheets and study the budgets of people, companies and governments. In the data course, students would gather their own data sets and learn how, in fields as diverse as sports and medicine, larger samples give better estimates of averages. In the basic engineering course, students would learn the workings of engines, sound waves, TV signals and computers. Science and math were originally discovered together, and they are best learned together now.

— Garfunkel and Mumford, 2011: How to Fix Our Math Education in the New York Times
— ↬ The Dish ↬ Finding the Next Einstein

Which seems like a good idea — more of an apprenticeship-style approach to math — but there still needs to be some space for the wonderful elegance of some of the apparently more abstract math. More real world applications could certainly be incorporated into the current curriculum, but it would be short-changing our students if we just left math for problem solving and did not delve a little into the principles behind the mathematical techniques they’re using in a more general way.