Instant Gratification


Instant gratification is definitely taking to long these days. We all want faster computers and that usually means faster memory access as well as CPU clock speeds. The new player on the horizon is memristors.

These promise denser memory storage, faster access and, ultimately, my gratification time taking a dive. Engineers have been clawing their way towards this current Holy Grail for some time now, but the materials have been a little more exotic than good old silicon.

The good news is that thin films of partially oxidized silicon do just fine. Mehonic et al published their data in the Journal of Applied Physics last month (1) and presented it to the cognoscenti at the European Materials Research Society conference which was reviewed by the BBC (2).

Thin silicon films respond to a small current that leave behind a resistive trace in zones of around 10nm. The access speed is about 100 times faster with a much lower potential power consumption.

So not only will my laptop be much faster in the future, but it won’t cook my vitals as I use it on my lap on the train. And the battery life, well that might be magnificent too.

  1. http://jap.aip.org/resource/1/japiau/v111/i7/p074507
  2. http://www.bbc.co.uk/news/science-environment-18103772



A Whales Mute Button


Low frequency sound waves travel a long distance in water and humpback whales can communicate over very long distances. Dolphins and toothed whales produce short bursts of sound that they focus into a directional beam using their bulbous forehead. They use this for echolocation of fish, but the sounds can be very loud and disturbing if you are nearby – 230 decibels would be uncomfortable up close.

The reflection from a fish for dinner some distance away will be very quiet, so how come these mammals don’t deafen each other when they are in a group looking for dinner?

Well, I didn’t hear the buzz about this that was presented by Nachtigall and Supin at Acoustics 2012 (1) who had asked and solved this question with their well-behaved friend Kina, a false killer whale, by checking out her brain activity when the made some noises. The BBC have reviewed their presentation (2).

They made noises which were quietly innocuous and increased the beeps to 170 decibels which would make me duck and run for cover. Kina’s brain activity increased in proportion to the decibel rating, but they found that if they played a quiet sound just prior to the very loud one, she figured out what was coming and turned the volume down on her ears as they figured out from her brain activity dropping proportionately. She has a sort of whales mute button.

Not quite the complete mute button like our teenagers seenm to activate when we ask them to tidy their rooms.

  1. http://acoustics2012hk.org/abstract_detail.php?number=4aAB3
  2. http://www.bbc.co.uk/nature/18085158



Java Jive


It appears that consuming caffeine is causing a buzz around the computers of some of the epidemiologists of the NIH in Rockville. The old picture of the dedicated scientist poring over a problem, drinking cup after cup of strong coffee and smoking one cigarette after another no longer holds, but the coffee, well that’s another story.

Apparently the old lyric line “I love the Java Jive and it loves me” (Inkspots & Manhattan Transfer for the youngsters out there) has more than an element of truth. Freedman and his team at NIH have dug into the records of over 5M people who were given the third degree on their eating and coffee consumption habits back in 1995 and checked how many were still above ground in 2008. Their results are reported in the current edition of the New England Journal of Medicine (1) and slow filtered by Reuters (2) (I guess journalists also have that coffee drinking/smoking image too).

Nearly 34k men and 19k women had died out of those in the original cohort, who were between 50 and 71 in 1995. The question asked was ‘what did their coffee drinking do for them?’ The number crunching began and after the figures were adjusted for age and smoking habits, the computer spat out the good news.

Guys who were into the java jive to the extent of 6 cups per day were only 90% as likely to pop off as those who had under a cup per day. Even better news for women. 6 cups a day dropped your chances to 84%. We should note that people who already had heart disease, cancer or had a stroke were excluded from the original selection of participants.

It is interesting that the authors are hedging their bets though. They’re uncertain if the effect is causal. I’ll get back to my brew and wait for the next installment.

  1. http://www.nejm.org/doi/full/10.1056/NEJMoa1112010
  2. http://www.reuters.com/article/2012/05/16/us-study-death-coffee-idUSBRE84F1DK20120516



Virus Power


Bacteria have potential for manufacturing a wide range of materials, but they also play host to viruses called bacteriophages. The M13 bacteriophage is one such species which propagates rapidly inside an infected bacteria.

The M13 phage is a small rod shape virus (880nm x 6.6nm) and when concentrated, the rods line up to form liquid crystals with a structure reminiscent of corn in a cornfield.

With a little bit of protein modification, Lee et al have formed these into stable multilayers on a gold surface (1). They then made a sandwich of the M13 phage film with another gold surface. After a bit of soldering and embedding the sandwich in a Silicone rubber block they had a tiny device that generated a voltage when squeezed.

The viral film is piezoelectric, so more squeezing gives more output, sufficient to turn on a liquid crystal display. This took a multilayer of twenty units covering an area of around the size of a key on your computer keyboard. Maybe one day soon we’ll be typing using virus power.

  1. http://www.nature.com/nnano/journal/vaop/ncurrent/pdf/nnano.2012.69.pdf


Education Is Good For You


 Education is good for you and we all get some even if it is at the hands of our parents and peer group. In general we expect the population to go to school, learn lots of good stuff and then make a good living with that knowledge so that we can all enjoy the good life.

Way back in the last century, the Swedish government decided to run an experiment to see if education and the subsequent mortality of the student could be causally linked. So for the years 1949 to 1962, the government picked out students in a large number of places to get an extra year of compulsory school time,or not. They had to have controls.

They have had a long wait for the results to come in and finally, Lager and Torssander have crunched the numbers and reported out in last week’s Proceedings of the National Academy of Sciences. There were a deal of numbers to crunch.1,247,867 in all with 92,351 now dead.

Up to 40 the mortality rate was unaffected by education, which is interesting as I suppose they were all pretty healthy and were careful drivers. However, after 40 things appeared to change. Compulsory schooling seemed to be a good thing. The hazard ratio as a percentage was down to about 94%, so it’s a small advantage, but maybe worth having. Vocational training on top eased the hazard ratio, again as a percentage, down to 92%.

With any population there is a spread of responses and the variation was around ±4% so the authors conclude that the length of your education doesn’t really do anything for your life expectancy – relative to your peer group of course. Perhaps they should start a new study in a less developed part of the world than Sweden.

  1. A.C.J.Lager & J.Torssander,Proc. Nat. Academy Sci. (2012) DOI:10.1073/pnas.110589109


Chronically Smoking Rats


 Smoking cigarettes is generally accepted as being bad for us and there are lots of studies around second-hand smoking, though the term “passive” is probably a better descriptor. There are a large number of conditions that are a problem due to cigarette smoke in addition to heart and lungs.

Apparently it appears to be a factor in the development of Alzheimer’s and dementia. There appears to be some evidence for it being a risk factor for cognitive decline in that it may enhance the rate of decline. Ho et al decided to tackle this from the neuropathology angle to get a measure of the chemical and structural changes that can occur in the brain of chronic smokers. Their results are published in the Public Library of Science (1).

The chronic (passive) smokers in this case were 5 rats who jointly (so to speak) were consuming 12 cigarettes in a one-hour session held every day for 56 days. The preferred smoke was filter tip Camels, but like most passive smokers, they didn’t get a choice of brand. There were also 4 rats who ran around in nice clean air for that same hour and were the control group.

There was no cognitive testing of our rodent friends, but each one had its brain examined. In a great deal of detail, I should add. The results were quite clear with signs of oxidative stress in the hippocampus of the smokers as well as a decrease in pre-synaptic proteins.

This is bad news as we all want our synapses to give us increasing connectivity. The spikyness of the neurons was also decreased. These two things look like a decrease in plasticity, that is a sign of cognitive decline. Other proteins were also affected. All in all the synaptic decline was indicating the path of a neurodegenerative  condition.

There was no sign of senile plaque and the authors point out that smoking is only one risk factor for Alzheimer’s. Anyway 56 days for chronically smoking rats is quite a short time.

I feel compelled to wonder if, after that short time, were they hooked? And given the choice, would they have opted for a patch or chosen to go cold turkey if the dangers of signing up for this experiment had been explained to them?

  1. http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0036752



Seek And Ye Shall Find, Maybe


Some of us have been known to be referred to as "squirrels” because we tend to collect things, things which are often not of a great deal of use, but that is rather maligning the squirrel. A thrifty squirrel, like many other small mammals and some birds makes food caches for the winter.

As they don’t want other squirrels or mammals to find the cache and devour everything, they use many small caches, which leaves them with a memory problem. Now Legge et al of the U of Alberta began to be concerned about people squirreling stuff away and other people finding it, so they carried out a study with over a thousand undergraduates who had been away from home long enough for them to be no longer relying on their moms to keep track for them. They published their results in PLoS ONE last week (1).

The experiments were in two locations – a real room with 70 floor tiles to hide things under and a virtual room on the computer which looked somewhat similar. They ran a series of experiments where they had to hide cards and others had to seek, through limited choice seeking to the participants having to find what they had hidden.

Depending on the seek and ye shall find strategy  people tended to seek in dark corners but hide things in the center of the rooms. With limited search choices available, the strategy was to disperse widely and when they knew that they had to be able to relocate their own stuff (without mom’s help remember), they tended to hide stuff in the middle of the room so that they wouldn’t have to cast about so widely.

Well, this seems to show that people use different strategies for thinking about locations when hiding things than when searching. That is hiding things in the well-lit center of a room, but scrabbling about in dark corners looking for stuff. Quite a disconnect in logic there.

It is interesting that the authors suggest that future work may be focused on searching for contraband or IEDs. More likely the first use will be in developing more difficult computer games where participants have to collect hidden objects to progress to higher levels.

  1. http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0036993