Thursday, October 22, 2009

Walrus Torontohenge contest


Since at least 2002, when astrophysicist Neil deGrasse Tyson gave it a name, photographers in New York City have observed the passing of Manhattanhenge, which happens when the rising or setting sun perfectly aligns with east-west streets that follow the island’s 1811 planning grid. The phenomenon occurs in every metropolis with a similar plan, and is coming soon to Canada’s city of skyscrapers. According to The Photographer’s Ephemeris, a free application developed by landscape photographer Stephen Trainor, the next Torontohenge is due to illuminate T.O.’s downtown thoroughfares on the evenings of October 24–25.

The Walrus invites local photographers to send us your best photos of Saturday and Sunday’s Torontohenge effect. Bree Seeley, our picture editor, will choose her favourite images for a gallery to be published on The overall winner will receive a gift bag from Drawn and Quarterly; two runners-up will each receive a pair of tickets to The Walrus events at the International Festival of Authors. All three winners will also receive a complimentary one-year subscription to The Walrus.

Keychains, wtf?

I've been thinking about keychains lately... no, not really. But, I really never understood the point of them, unless they could be of some use. I suppose it depends on your trade. Here are three I actually like.

“The Bullet” bicycle valve adapter.

Also, an earplug keychain I got at some CMW years ago.

Other than that, are there any other useful keyhains? Maybe an adapter for your phone?..

I am now officially procrastinating.

The secret magic of... Photosynthesis, Chlorophyll, The Electron Dance, and Quantum Physics

So, back on this topic of leaves ('tis the season); what about the magic of chlorophyll? The thing that really blows me away about photosynthesis and chlorophyll is the efficiency of energy transfer. Typical power lines lose 80% of their energy transfer in heat loss and resistance. Our most efficient (experimental non-commercial) solar panels may reach 40% sunlight conversion efficiency. A plant can absorb, transmit and store (as sugars) up to 99% of the suns light.

SO, why the huge discrepancy?

The quantum yield of a light harvesting system is typically very high. It is given by a near unit probability, as most every photon absorbed by the chlorophyll network results in an electron transfer.


Directly from here, here and here:

One of the most significant quantum observations in the life sciences comes from Fleming and his collaborators. Their study of photosynthesis in green sulfur bacteria, published in 2007 in Nature, tracked the detailed chemical steps that allow plants to harness sunlight and use it to convert simple raw materials into the oxygen we breathe and the carbohydrates we eat. Specifically, the team examined the protein scaffold connecting the bacteria’s external solar collectors, called the chlorosome, to reaction centers deep inside the cells. Unlike electric power lines, which lose as much as 20 percent of energy in transmission, these bacteria transmit energy at a staggering efficiency rate of 95 percent or better.

The secret, Fleming and his colleagues found, is quantum physics.


Electrons moving through a leaf or a green sulfur bacterial bloom are effectively performing a quantum “random walk”—a sort of primitive quantum computation—to seek out the optimum transmission route for the solar energy they carry. “We have shown that this quantum random-walk stuff really exists,” Fleming says. “Have we absolutely demonstrated that it improves the efficiency? Not yet. But that’s our conjecture. And a lot of people agree with it.”

(which electron path is the most efficient - random walk trial)


Stuart Hameroff, an anesthesiologist and director of the Center for Consciousness Studies at the University of Arizona, argues that the highest function of life—consciousness—is likely a quantum phenomenon too. This is illustrated, he says, through anesthetics. The brain of a patient under anesthesia continues to operate actively, but without a conscious mind at work. What enables anesthetics such as xenon or isoflurane gas to switch off the conscious mind?

Hameroff speculates that anesthetics “interrupt a delicate quantum process” within the neurons of the brain.


Ok. This is pretty ground-breaking quantum science. Or, evolution research. Well, both really.

Evolutionarily, it seems there was a single initial pathway to the creation of photosynthesis, started over a billion years ago. The pathway diverted from the original cyanobacteria (usually mono-cellular water creatures) to the plant pathway. There are many similiarities and many differences - ie. some things were kept/unchanged in a billion years, some things were added/adapted). Both photosynthetic pathways are highly efficient; the plant one only slightly more efficient with added complexity. Why?:

"We suggest, therefore, that constraints other than excitation transfer, such as ligation of chlorophylls, electron transfer, photoprotection of chlorophylls by carotenoids, spectral composition of pigments, and the requirements of assembly, and possibly repair, are likely to play determining roles in shaping the evolution of a light-harvesting system. The apparent lack of optimality of the geometry of the peripheral chlorophyll network suggests then that the aforementioned issues display a higher priority for the fitness of the system than the excitation transfer process" (via here).


Anyway, where does this leave us? Well, we obviously have a lot to learn. Chlorophyll is certainly a major player, and we are experimenting with it a bit, from chewing gum (acts as a very mild odour eater) to night vision.

There's even progress in the use of chlorophyll to aid in a photoshynthetic transfer within solar panels. If you can't beat'em, join them? We obviously have a long way to go. (plants in photo cells)


Lately I've been on this kick where I just research the shit out of a topic, learn about it, get too busy to write about it, and never end up doing anything with it. I have a backlog of items that I wanna talk about, record here and get feedback on.. and not all of the science influence either...

I also have a bit of a surprise coming up(!), but that's gonna have to wait a bit... Maybe a week, if that (I hope!) Just starting up the hype machine!

I'm in the middle of finishing up law school apps. Once that's done, I hope to catch up here a bit, especially with the music and art, as that takes more care than just reading, copying and pasting science interests. At least for me. I'm not the type of person who can work and listen to music at the same time;

Anyway, here's a pretty cool and simple post from A three year old's view of the NYC subway system.

A Toronto version would be a great Christmas gift idea...

UPDATE: like this:

So, why do leaves change colour?

If you, like me, said 'chlorophyll, something, something... ', read on.

Many people think deciduous trees lose their leaves because of cold weather and frost, a common misconception (umm.. my misconception), but actually the length of the day seems to be what determines when trees begin the process of changing colours and dropping leaves. During the shortened days of autumn there is not enough sunlight to outweigh the costs of chlorophyll maintenance and production, and the tree goes into hibernation mode. Once chlorophyll has stopped being produced, the red, golden and brown colours are "unmasked"; these colours are actually the natural colour of the leaves without the chlorophyll.

So's, why are the two pigments (carotene (responsible for yellow, orange and brown) and anthocyanins (red)) there in the first place? I mean, what is the evolutionary benefit of a leaf having these pigments? What is the benefit of having them show up there in the fall? It obviously just can't be a ho-hum, whateves decision on nature's part.

The pigments that produce yellow and orange leaves in the fall are present year-round, and help protect chlorophyll, the molecule at the heart of photosynthesis, from sunlight damage; when chlorophyll is broken down in the autumn those yellows and oranges become visible. In contrast, the red anthocyanins are produced only in the fall. It is a costly job of molecule building for the plant and an enigma to scientists, since the leaves will at that point soon be dropped entirely [BBC News]. (via discovermag)

Apparently no one knows why yet.

Possibly, the red colour could be a signal to insects that the leaves, and tree, are malnourished or have a built in chemical defense. This was postulated based on a single certain insect (aphids) that were less likely to grow to maturity living on red leaves rather than yellow or green leaves... this seems plausible, but yeah, where is the benefit to the tree?

Another possibility? David Wilkinson, an environmental scientist at Liverpool John Moores University who has published on the leaf colour debate, says that the work is not proof positive of the co-evolution theory (of insects and trees).

"I think the most likely explanation is that these [anthocyanins] are effectively sunscreens that allow the photosynthesis to continue as the machinery of photosynthesis is broken apart in the autumn.

"The idea of, as it were, 'the trees are talking to the insects', is wild and wacky and it would be rather nice if it were true.

"But I still have not seen anything that convinces me of the signaling."

(photo from Sarah used totally without permission - UPDATE: Now with permission!)

This goes under the wait until next year pile, as experiments can only be done at specific times... maybe we'll get an update soon.