Archive for March, 2010

Breathing a sigh of relief

March 29, 2010

BBC News – Gulf Stream ‘is not slowing down’

Between 2002 and 2009, the team says, there was no trend discernible – just a lot of variability on short timescales.

The satellite record going back to 1993 did suggest a small increase in flow, although the researchers cannot be sure it is significant.

“The changes we’re seeing in overturning strength are probably part of a natural cycle,” said Josh Willis from Nasa’s Jet Propulsion Laboratory (JPL) in California.

“The slight increase in overturning since 1993 coincides with a decades-long natural pattern of Atlantic heating and cooling.”

It’s difficult to overstate just how much trouble the whole world would be in if that circulation stopped (as it has during other warming events).


The operation was a failure, but the patient lived

March 27, 2010

Robot Surgery, Thy Name is DaVinci | Singularity Hub

However, the company line on the DaVinci’s effectiveness is far from the last word. According to a large study of Medicare patients, robotic prostate surgery led to fewer in-hospital complications, but had worse results for impotence and incontinence (I know which one of those bullets I’d choose to take, just saying). Costing a cool $1.7 million, plus a $100,000+ annual service fee, inconclusive results are a bit hard to stomach. There are two reasons why this ostensibly advanced surgical method can lead to mixed results. First, the DaVinci provides no tactile feedback. Doctors have to learn to use the visual environment for clues they would otherwise get by feel. Of course, with the development of haptic feedback, this flaw might be remedied soon.

I’m sure all those practice patients feel really great about helping the doctors and the company master the learning curve of doing real surgery. It’s kinda telling that the article (and other articles) is pushing this gadget as the unstoppable future of medicine, rather than just another dead end that didn’t have quite the tech needed to do a proper job. And that hospitals are using it as a marketing tool to get patients to have their surgery there. “New! Improved! Worse results for you! Lower treatment costs for us!”

Will work for food

March 26, 2010 Hungry burglar leaves behind cash, dirty dishes

The burglar entered the Broadway Avenue restaurant early Saturday morning by breaking an exhaust fan at the rear of the store and climbing in through the hole, said officials. Nobody saw him enter and nothing else was taken besides the food to make the chicken and rice dinner.

Not legal work, but pretty hard work nonetheless.

It really makes you wonder about the person involved. The town (as the article notes) has a shelter and a food pantry, but whether they’re effectively available to this burglar isn’t clear. If they’re willing to work that hard for one meal, would they be willing and able to work legally? Were they just drunk or high with the munchies?

For someone there’s a bad novella to be written starting from here.

Dani Rodrik, right as usual

March 17, 2010

Dani Rodrik’s weblog: Why do economists disagree?

A second argument is that the presence of additional market imperfections does not change the first-best logic; it simply calls for each market imperfection to be treated with its own first-best solution. This allows each expert in a field to propose first-best solutions in that field, leaving complications elsewhere to be dealt with by others. Larry Summers had a nice point to make about this approach in his comments on a paper on banking reform in China (Brookings Papers on Economic Activity, 2006:2):

Like experts in many fields who give policy advice, the authors show a preference for first-best, textbook approaches to the problems in their field, while leaving other messy objectives acknowledged but assigned to others. In this way, they are much like those public finance economists who oppose tax expenditures on principle, because they prefer direct expenditure programs, but do not really analyze the various difficulties with such programs; or like trade economists who know that the losers from trade surges need to be protected but regard this as not a problem for trade policy.

This used to piss me off no end when I was talking to economists. The “free” traders always thought it was sufficient to show that the aggregate gains from increased trade were sufficient for the winners to compensate the losers, but showed no interest in making sure that the compensation actually took place. (There was a strange disconnect in their positions — they argued for “free” trade as some kind of moral good because it increased overall wealth, but the fact that it virtually always resulted in more wealth for some groups and less for others was somehow morally neutral.)

The first-besters remind me of the famous joke about the mathematician and the hotel fire: he dabbles his finger in the water from the tap, murmurs “a solution exists” and goes back to sleep.

OK, everybody in San Francisco drop your laptops.

March 17, 2010

Is a lot of lousy data better than no data at all?

The “Quake Catcher” software is designed to record all vibrations on a computer, but only uploads the info if many computers in the same geographic area record “dramatic shaking.”

Now here’s the thing: serious earthquakes: typically associated with power outages and telecommunications failures. So you’re relying on the notion that in the few seconds before the earthquake brings down your local internet connection, your computer will be able to transmit useful data. Because otherwise no one is going to know there was an earthquake. Uh.

Would this thing be of any use outside the immediate disaster zone? Maybe. A computer accelerometer can do about 1/250 of a g, which corresponds to the bottom of the “weak shaking” category in earthquake effects. If you look at the USGS shakemap for Haiti, for example, all of the island of Hispaniola and parts of nearby islands in the caribbean registered enough shaking to trigger any hypothetical laptop detectors. That could give you a good idea of location and magnitude a few minutes or even an hour before official observatories.

And of course for seismologists reconstructing the disaster in later months or years, the data could lead to any number of publications.

Octopus has no hobgoblins

March 15, 2010

HDTV reveals brainy octopus has no personality – life – 12 March 2010 – New Scientist

Octopuses that reacted to one film aggressively tended to respond to all films on a particularly day in the same way. But over longer periods of time, any trace of “personality” or consistency evaporated. They might react aggressively one day, but much less so on another day. “It’s a bit of a surprise,” says Hanlon. Other cephalopods, such as the dumpling squid, display consistent personalities for most of their lives.

This lack of consistent behaviour may be related to octopuses’s huge brain size, relative to other cephalopods. Big brains may “afford octopuses considerable behavioural flexibility that allows them to change their behaviour adaptively over time,” write the researchers.

This definition of “personality” is a very interestingly stupid one. It ties something that sounds like a deeply innate complex of behavioral traits to whether the researcher can figure out a set of simply stimuli that will elicit the same behavior day after day.

most random tab dump ever

March 4, 2010

Lego Universe Impressions: The Next Step In Lego Building – Lego universe impressions – Gizmodo

There are two components of the game that are pretty tightly interweaved: the more traditional MMO portions where you use your skills and interact with other players to achieve goals and defeat monsters, and the building bit, where you have your own territory and can build anything you want out of Lego pieces.

Since everyone’s more interested about the building part, we’ll cover that first. Lego says you have access to pretty much every part they have, from many of the unique Lego sets over the years (pirates, space, etc.). You have your own “home” area that you can build castles or whatever inside, invite your friends to visit and customize however you like. You can also assign behaviors and actions to what you build as well, by dragging and dropping actions onto easily-connectible UI segments

15 House Plants You Can Use As Air Purifiers

Common name Scientific name Score
1 Areca palm Chrysalidocarpus lutescens 8.5
2 Lady palm Rhapis excelsa 8.5
3 Bamboo palm Chamaedorea seifrizii 8.4
4 Rubber plant Ficus robusta 8.0
5 Dracaena “Janet Craig” Dracaena deremensis “Janet Craig” 7.8
6 English ivy Hedera helix 7.8
7 Dwarf date palm Phoenix roebelinii 7.8
8 Ficus Alii Ficus macleilandii “Alii” 7.7
9 Boston fern Nephrolepis exalta “Bostoniensis” 7.5
10 Peace lily Spathiphyllum sp. 7.5

Technology Review: Graphene Transistors that Can Work at Blistering Speeds

In theory, graphene has the material properties needed to let transistors run at terahertz speeds at room temperature.

The IBM researchers grew the graphene on the surface of a two-inch silicon-carbide wafer. The process starts when they heat the wafer until the silicon evaporates, leaving behind a thin layer of carbon, known as epitaxial graphene. This technique has been used to make transistors before, but the IBM team improved the process by using better materials for the other parts of the transistor, in particular the insulator.

PLoS Biology: Evolution of Adaptive Behaviour in Robots by Means of Darwinian Selection

In this essay we will examine key experiments that illustrate how, for example, robots whose genes are translated into simple neural networks can evolve the ability to navigate, escape predators, coadapt brains and body morphologies, and cooperate. We present mostly—but not only—experimental results performed in our laboratory, which satisfy the following criteria. First, the experiments were at least partly carried out with real robots, allowing us to present a video showing the behaviours of the evolved robots. Second, the robot’s neural networks had a simple architecture with no synaptic plasticity, no ontogenetic development, and no detailed modelling of ion channels and spike transmission. Third, the genomes were directly mapped into the neural network (i.e., no gene-to-gene interaction, time-dependent dynamics, or ontogenetic plasticity). By limiting our analysis to these studies we are able to highlight the strength of the process of Darwinian selection in comparable simple systems exposed to different environmental conditions.

Smart soundproofing

March 4, 2010

Acoustic Metamaterials Could Make Ultra-Thin, Ultra-Effective Noise-Cancelling Panels | Popular Science

Each soundproofing panel consists of latex stretched over a 3mm-thick rigid plastic grid of squares, with a small weighted plastic button sitting in the middle of each square.

absorb, acoustic, metamaterials, reflect, sound waves, soundproof materials, soundproofing, sounds
Sound waves that hit the panel cause the latex membrane and weighted buttons to resonate at different frequencies that cancel out the sound waves. Individual membranes are tuned based on the weight of the plastic buttons, so that each can cancel out a certain frequency band of sound waves.

Stacking five differently-tuned membranes together can produce a soundproof panel that works from 70 to 550 hertz, and is just slightly thicker than a ceramic bathroom tile.

I’m guessing that the membrane need not be latex, in which case the whole damn thing could potentially be injection-molded fairly simply. As with most soundproofing schemes, the big deal will be eliminating paths for the sound to travel straight through and bypass all the smart stuff. I kinda want to try making some of this…