Thursday, March 29

From The Culture

>> Interac-shun

There's been an ongoing thread about the ways in which people act online compared to offline. What I find most interesting about the way in which communication is conducted online is that everything you say can be, and probably is, logged. I have about two years worth of logs from a few high-volume mailing lists probably coming out to over 50,000 emails. This year I've sent 3012 emails, 1190 of which have gone to public mailing lists. Should I ever decide to run for office, then I'd have to expect every single word that I've written being pored over meticulously - and the same situation might occur if I applied for a job. It's not impossible.

So the question is, does this put me at a disadvantage compared to at least 95% of the population who don't really use the Internet for communication as I do? Is it fair for people to judge me by the (undoubtedly) stupid things that I've said one time or other? To be honest, I don't really care (well, I say that now...) but while there aren't that many people using the Internet and mailing lists and email quite as much as I do, that will change and people will realise that their words will eventually haunt them. And then they'll decide that if they can make mistakes in what they say, then so will other people and we'll just have to accept it. Hey, I'm optimistic, OK?

>> Suggestion regarding a technology purchase

This thread started off with someone asking whether they should buy a Minidisc player or digital camera and eventually boiled down into a morass of discussion about the relative merits of various recording formats (CD, MP3, DAT, etc) as well as the different players. The general consensus is the Minidiscs are still going strong but are facing increasing opposition from MP3. The main problems with MP3s is that you need at least a basic understand of computers (ripping CDs or downloading MP3s) as well as hooking up wires and using the software - yes, it sounds easy and it is, but it still takes time. The quality of MP3s isn't really the problem here; if you use a bit-rate of 192kbs or preferable 256 then it's usually indistinguishable from CD quality. Of course, if you don't like CDs then it's an entirely different thing.

You also have the problem with the build-quality of MP3 players. The only MP3 players really worth buying are the 'jukebox' models with around 6GBs, capable of storing about all the music you'll realistically want for at least a couple of weeks of solid listening. Consequently the jukebox models are larger than any Minidisc player you could want, or the smaller capacity MP3 players, but you have to consider that you don't have to lug about a load of MDs or CDs. But - build quality. You don't have well-known brands making these jukebox players, you only have Creative Labs and some other small company doing it. Personally that doesn't bother me but I know that won't be the case for everyone.

Just before the thread mutated into something about 'undercurrents' there was a confused flurry of posts about DVD audio formats as well as DVD-RAM, DVD-RW, DVD+RW and all that nonsense. I gave up trying to understand all of that a long time ago.

>> Dubya decides to trash world

Just to show that I'm not ripping all of my weblog content off the Culture list, I actually started this thread myself after watching Sky News and reading this article about how George Bush (and thus the United States) has pulled out of the Kyoto Greenhouse Gases Treaty. Justifiably, there was much wailing and gnashing of teeth on the list as well as some dark speculation on how long he'll last (in the White House, and as a living human being). We have this thing called a Cynicism Index on the Culture list which gets polled every so often - more than one person has dropped their scores a few points after hearing this (meaning that they are more cynical about the world).

It's always easy for people, and by people I mean the industrial lobbyists, to claim that there isn't really any global warming taking place and it's just an artefact of measuring temperatures in heat islands, or all of this change is part of the ice age or Milankovich cycle, but frankly the evidence is mounting up. Right or wrong, do we really want to risk the future of every single beach and coastal city in the world just because America is so unimaginative in resolving its 'energy crisis'? The most telling comment in the Sky News segment was when someone mentioned that George Dubya Bush 'doesn't believe in global warming'.

>> Shipnames...

Amanda wins the shipname of the day with:

VFP Sarchasm: The gulf between the author of sarcastic wit and the reader who doesn't get it.

4:59 PM | permalink | discuss

Wednesday, March 28

From The Culture

X-ray goldfish: Well, not quite. It turns out that goldfish are unique among animals in that they can see into both the infra-red and ultra-violet regions of the spectrum. This topic arose when someone claimed that goldfish might be able to see through metals (hence 'x-ray vision'). While some group 1 metals are transparent to UV light with a wavelength shorter than 315nm, it's thought that goldfish can probably only see to as short a wavelength as 360nm. It's still an interesting question though; obviously the ability to see through man-made metal isn't exactly the most important survival trait that goldfish have, so why can they see IR and UV?

The answer for IR is quite simple - at short distances it can penetrate murky water much better than visible light. With UV, we're not so sure. Possibly the goldfish have markings along their scales that are only visible in UV? It certainly wouldn't be unusual as many organisms, insects and birds in particular, can see into the UV since flowers often have UV-only patterns. However, more research is obviously required here.

Added Value: Some fish can also detect objects in murky water by sensing the electromagnetic fields that they produce - and we're not talking about electric eels here either. Due to the electrochemical potential difference between the fish and the surrounding water, they produce electric fields that can be picked up by electrosensitive cells. Even more impressive is the way in which some fish can 'cloak' themselves with an electric field identical to that of the surrounding water.

Contributors were Phil Dyson, Richard Baker and Charlie Bell

Tetrachromacy: Following on from the topic of vision, why is it that we see the colours that we do? Why can't we see into the UV and IR? Richard Baker presents a good summary:

Firstly, there are physical limitations on the wavelengths we could use, because at long wavelengths there would be too much interference from the infrared light given off by the creature's own body and at short wavelengths lenses made of biological materials don't work (although I guess it would be possible to use mirrors - there are some animals that have mirror-focused vision). Within that range, it's probably best to be able to see in the yellow-blue range because most of the ambient light intensity is in that band. If you're living underwater then I suppose the optimal range of wavelengths is different because water has different optimal properties to air. Some animals see polaristion too and that may also affect the optimum range of wavelengths.
In addition, one of the main reasons that most animals cannot see into the UV is because UV light damages cells and DNA. While it is possible to produce countermeasures that will protect your cells against UV, these all have a metabolic cost - they require energy to produce and maintain. Therefore, the only organisms that can see into the UV have a good reason for doing so and clearly we do not.

In order to understand what I'm going to talk about next, it's important to get a basic understand of how we actually see. In our retina we have photosensitive cells that contain pigments that, when hit by a certain wavelength of light, change their shape and send a signal to the brain (my supervisors would kill me on hearing this explanation but it'll have to do for now). We have three different types of pigment that correspond to red, green and blue wavelengths of light. When we see a wavelength of light that is in between red and green, then it stimulates both the red and green pigments in varying amounts, and the resulting 'colour' that we see is a mix of red and green.

Only very recently in evolutionary timescales, the branch of organisms from which humans evolved only had two colour pigments. It's thought that we gained a new pigment around the time that we evolved into monkeys, through a process in which one of the existing pigments was duplicated and mutated. Why did we gain this new pigment? What evolutionary pressure was there? Well, researchers have shown that the development of this pigment would have been instrumental in letting us distinguish healthy and ripe fruits and leaves from those that were not - and having that ability would definitely be an evolutionary advantage.

Tetrachromacy, however, is the situation in which a human has four pigments - meaning that they can distinguish colours even better! It's not common, but it does exist and has some startling implications. A quote from the link above:

True tetrachromacy would require a few other characteristics in addition to retinas with four different photopigment receptors. For instance, there would have to be four neural channels to convey to the brain the sensory inputs from the four receptors, and the brain's visual cortex would have to be able to handle this four-channel system. If a woman were born with four types of photopigments, would her brain wire itself to take advantage of them? No one knows for sure, but some experts strongly suspect it would. "Yes, definitely," says Jeremy Nathans, a pioneer in color-vision research at Johns Hopkins University School of Medicine. One reason to think so is the brain's great plasticity in other respects. People with special skills -- musicians, bilinguals, deaf people who learn sign language -- often show characteristic brain patterns."
This clearly has huge implications for wiring us up to computers and whatnot to receive extra information. After all, imagine if you wanted to be able to see in IR and UV. You wouldn't want to do that cop-out method of translating the IR or UV onto our visual spectrum (as they do in movies), you'd want to simply expand your range naturally. And the fact that the brain can wire itself to do this in some circumstances is very neat. However, you can't expect to introduce a new artificial sensory input to an adult brain and expect it to rewire itself automatically - it's likely that the initial growth phase of the brain would be when the rewiring takes place.

Contributors were Charlie Bell, Richard Baker and Phil Dyson

So that's all from the Culture today, I hoped you enjoyed it and it was worth me writing all of this up. This could turn into a daily feature, if I can be bothered.

Two very neat things should be arriving at my house tomorrow: a DVD of the first season of Spaced, and a Visor Deluxe I ordered off eBay... far too much fun.

11:53 AM | permalink | discuss

Tuesday, March 27

I've recently hit upon a problem of finding stuff to write for Vavatch. I don't want to bore you with mundane details and I can't spend hours trawling the web for useful links. In fact, most of the interesting stuff that I write these days gets posted to the Culture list - except that I know that Culture members read my weblog and I'm not too keen on just recycling my posts in fear of boring them.

So - here's an idea. Since the best writing goes to the Culture, and it would be a shame to waste it, what I'm going to do from now on is to take the two or three most interesting issues discussed on the list and, through Vavatch, describe and expand on them, providing links and information and my own personal spin. I think this will usher in a new, more original and lively Vavatch.

Starting from tomorrow, of course.

11:20 PM | permalink | discuss

Monday, March 26

Today we'd hung out some washing to dry outside. A few hours later, while I was reading a magazine in my room in front of the window, I looked up and narrowed my eyes at the grey clouds that had appeared. I considered them for a few seconds, weighing up the probability that it would start raining in the next few minutes and then decided that on balance, it would be okay. About a minute after that, something whizzed past the window and I glanced out of the window again. Nothing. I peered over the window sill to check if I could see whether there were any splashes in the water that was lying on top of the conversatory. Nothing.

Satisfied that it really wasn't going to rain, I sat back and five seconds later it started raining. I sprung into action immediately, diving out of the door, running down the stairs, pausing to pick up the laundry basket and then hurled myself out of the house in order to save the washing. Once all of that was done, just as I'd finishing collecting it all, it stopped raining.


I've been wondering whether it's strange that I watch, on average, less than 30 minutes of TV per day now. I don't have access to a TV at university so I'm finding it difficult to tell what's on these days and I don't really have the inclination to check the listings. Usually I'll only make the effort to watch perhaps Futurama or Spaced - to be honest, I wouldn't know if there was anything else decent on. Maybe it's just because the TV-watching centres of my brain has atrophied due to misuse, but has anyone considered that there is very little worth watching, despite what the media and advertising are trying to tell us?

2:18 PM | permalink | discuss