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Accident prone?

Bruises happen when connective tissues and muscle fibres under the skin are compressed but the skin doesn’t break. With a graze or a cut, the blood can easily escape but with a bruise, blood from your ruptured capillaries can’t. And with nowhere to go, the blood is trapped.

Bruises generally go through a whole range of colours. If you have a really nasty whack, it will start off red then within the first couple of days turn a purply-bluey colour. Within 5 to 10 days, it develops into a greeny-yellow and finally, before it fades away after about 10-14 days, it’ll go yellowy-brown. This obviously depends on the severity of a bruise, your age, if you’re on any medication or have an illness which means you’ll bruise more easily.

When the red blood cells break open after you hurt yourself, they release substances which signal the body to send white blood cells to the healing site and cause all these weird colour changes. The white blood cells consume the hemoglobin and then release chemicals which cause inflammation.

Your bruise will start off red because the tissues surrounding it fill with blood. The most significant substance of red blood cells is hemoglobin – the protein which makes blood red.  The next colour, purple, is caused by the hemoglobin being broken down and losing its oxygen. This happens immediately after the injury and persists until all of the hemoglobin is broken down. The first breakdown product of hemoglobin is called a chemical called biliverdin, which appears within a few days.  Biliverdin is green which is why after the bluey-purply phase, your bruise will go green.

The green biliverdin is then converted to a yellow molecule called bilirubin. And finally the brown colour, just as your bruise vanishes, is caused by hemosiderin – another chemical converted from bilirubin. And there we go. From red to blue to green to yellow to brown. Bruises really are fastinating.

 

Can you ever beat the bookies (one year on)?

It’s that time of year again and after the roaring success of evidence-based predicting last year’s Grand National live on BBC Radio York, I thought I’d have another crack. I might have been wise just to give it a miss this year and insist my system works just fine after one outing but I wouldn’t be a proper scientist if I did that. Last year, I managed to predict 5 of the top 7 placed horses and bagged myself a profit. I happen to think that that’s quite good. But can it be reproduced in 2012?

This year is different from the last. I’ll get all the excuses out of the way now. I’ve been busier for a start. I’m currently moving house, tomorrow in fact. I’ve been away with work for 3 days this week. We’ve had two bank holidays. I’m on annual leave next week. The list goes on. So I’ve not had the chance to apply quite the same level of anal-ness to this year but I’ll give it my best.

Age

Probably the first trend you notice is that 8 to 12 year old horses tend to win. Younger ones have lack of experience over the fences and poor stamina. Older ones are just knackered and that, I believe, is the correct technical term. The peak age of winners seems to be 9 to 11. So, I’ve discounted every horse who isn’t aged 9, 10 or 11. Risky.

Stamina

I need my horse to have won over at least three miles fairly recently. It’s a hard course and they need to stay the distance. So all the horses that have raced over short distances are cut from my list. As important as that, they need to be able to jump, so horses that haven’t raced in steeplechase races recently are out. Usual fallers have to be discounted too.

Class

I’ve looked at other Nationals; the English, Scottish, Irish, Welsh or Kerry Nationals. Roughly 80% of the winners in the previous few years not only raced but were placed in the top 3 in any these Nationals.

Weight

Looking at the past few Grand Nationals, any horse carrying from 10 stone 4lb to 11 stone 5lb seem statistically more likely to win. So they’re my limits too.

Nationality

Apart from a couple of years ago, French horses tend not to do so well. I’ve got to narrow the field down somehow and this seems like another factor which is important.

So how many are we left with this year? I had 10 last year and I’m going to go for the same this year. Annoyingly, this means a bit of guess work as more than 10 fit these criteria but you can’t bet on 18 horses can you? The great thing about the National is that it’s such an open race. These 10 might all trip up (can horses do that?) before they reach the first fence but it’s a risk I’m going to have to take.

Here are my predictions, in no particular order, with their rough current odds.

  • Treacle, 20/1
  • The Midnight Club, 33/1
  • Calgary Bay, 33/1
  • Chicago Grey, 16/1
  • West End Rocker, 14/1
  • Giles Cross, 12/1
  • Planet of Sound, 33/1
  • Sunnyhillboy, 18/1
  • Cappa Bleu, 16/1
  • According to Pete, 33/1

Thanks to the people who got in touch with me on Twitter who said I should do this again. I know bugger all about horse racing but I do like patterns and evidence-based predicting. I urge you not to follow these tips. You have been warned.

Can you really predict the Lottery numbers?

I think we’ve probably already established I am a geek. So the fact that I look for patterns in six numbers drawn twice a week won’t come as too much of a surprise. But no, you can’t really predict the Lottery numbers and if you came to this blog in the hope that I’d say yes then you’re more gullible than the time my boyfriend told me you could see Norway from Scarborough on a clear day (yes, this did happen… and for a moment I believed him).

You can statistically increase your chances of winning by probability and looking at trends in previously drawn sets of numbers. The odds of you winning the jackpot are about 1 in 14 million but you’ve got a far more realistic chance of winning a tenner – a mere 1 in 55 chance. Now those are my sort of odds. No one can predict which numbers which will win but there are sets of numbers which are more likely to lose and it’s those I want to share with you.

You’re far less likely to win if you play your six numbers from the same set of 10 – 30, 31, 33, 35, 37, 39, for example. As far as I’m aware, no one’s had a jackpot win with 6 numbers from the same set of 10 so there’s little point in trying it.

It’s not advisable to play dates and it’s amazing the amount of people who just use numbers 1-31. If you do play dates then you’re in good company – loads of people do it. What that means is you’re not only missing out on 18 numbers but if you do win, you’ll have to share your jackpot with others. And hands up who wants to win a measly £500,000 when there’s potential for much more?!

Winning numbers are generally spread across the whole field. So if you take the number 25 as being the median, don’t pick all your numbers from 1-25 or from 25-49. Roughly 2 % of lottery draws contain all highs or all lows. So you can greatly increase your chances of winning by choosing a broad spread.

It’s wise not to play consecutive numbers. No lottery draw has had 6 consecutive numbers. I don’t think they’ve even had five. And only about 6 percent of draws have four neighbouring numbers. So space them out. Having said that though, you might be wise to have two numbers next to eachother. Half of the draws contain two consecutive numbers and this strategy will also make it less likely that you’ll have to split your winnings because few people opt for consecutive numbers, believeing that they hardly ever occur. Ha, the fools!

Also, please don’t be a complete tool and use numbers from the previous week either. A massive 42 % of numbers are not repeated in the following draw and 40 % of the time only 1 number is repeated.

I wouldn’t advise playing all odd or all even numbers either because the chances of it happening are very slim. You have a 1.2 % chance of all odd numbers or all even numbers but a massive 35 % chance of 3 odds and 3 evens. In other words you’re 29 times more likely to win if you choose 3 odds and 3 evens over all odds or evens.

I’m no Derren Brown but there are subtle ways of increasing your chances of winning. Perhaps not the jackpot… but will a tenner do?

Total lunar eclipse – 15th June 2011

I am almost a little too excited about the lunar eclipse tonight. Why? Well it actually feels like a bit of a secret. A quick sweep earlier seemed that not that many people I know knew about it. Tonight, the sun, earth and moon will all be aligned – the Earth blocking the sun’s rays from hitting the moon.

You’ll notice the moon will appear a deep red colour this evening because even though the earth is acting as a massive solar shield, some light will still hit the moon by passing through the Earth’s atmosphere. Incoming light from the sun is refracted or bent and these refracted beams can still light up the moon which is only blocked from direct sunlight. When light is diffracted, more of the blue and green parts are scattered. That’s why sunsets are red too.

Tonight isn’t like any ‘normal’ lunar eclipse. The Moon will sink deeply into Earth’s shadow, passing almost directly through its centre. This means it’s going to be a dark eclipse. The darkest for almost 100 years and we’ll have to wait a further 47 years to witness similar. Totality lasts about 100 minutes – the longest for 11 years and almost 40 minutes longer than the one we had just before Christmas last year. On a scale which measures lunar eclipse brightness, the Danjon Scale (which ranges from L = 0 (nearly invisible) to L = 5 (bright coppery-red)), tonight will be a 4.8.

All this adds up to an amazing astronomical event.

The eclipse begins at 18.24 tonight. Totality actually starts at 20.22 and ends as 22.02. Unfortunately for us, it’s only going to be visible when the sun sets tonight at 21.19. If there are few clouds, you’ll be able to see the difference in the moon as soon as the sun sets. The Earth is currently far away from the sun in its orbit (aphelion) and the moon is relatively close to the earth in its orbit (perigee) so the eclipse will last longer than usual so there’s no excuse!

Now look south-east, pray for clear skies and enjoy the view!

You can’t get anything past me!

I had to go to the hospital recently to have my eyesight checked. I sat in the waiting room and I struck up a conversation with 78-year-old Peter who’d undergone a corneal graft 10 years ago and comes in for annual checkups. My PhD focused on treating difficult to heal wounds by using different phases and concentrations of silver nanoparticles. Whilst firmly chained to the lab during my research, I got the opportunity to see my fair share of yucky wounds and because of that, nothing medically freaks me out. Because what he told me was horrific. Interesting but really gross.

I had loads of tests done at the hospital. The field view test, the Snellen Chart, a couple of scans to check for fluid build up and I had my eye pressure checked too for a signs of glaucoma. That was a strange one. Rather than the usual puff of air they give you at the opticians, I had some numbing drops put in each eye then, without much warning, a probe touched the middle of each pupil. ‘You’d have never let me do that without them’, the nurse told me. Feeling your eyeball squish backwards is an unusual feeling – not one I’d recommend for the squeamish. I also was asked by every nurse if I’d already had my pupils dilated because apparently…ahem… I have the biggest pupils they’d ever seen. I bet they tell that to all the girls.

After (top) and before (bottom) the dilating drops were added. Both pictures were taken in *very* bright light for comparison.

Finally, as you can see, I had the dilating drops. These stung a bit and made the world a peculiar place for a few hours. I couldn’t focus on anything due to the relaxation of my lens and because my massive pupils were letting in loads of light, everything was painfully bright. So as I talked to a vague shape of a doctor, I was told the good news – there’s nothing wrong with my sight. He then told me something pretty amazing.  I have 6/4 vision. I’d heard of 20/20 but no idea what 6/4 meant so he explained it to me, unhelpfully with diagrams that I couldn’t focus on.

Think back to the Snellen Chart with the letters of varying sizes to measure visual acuity, measured as a fraction (chart below). The numerator (top number) refers to the distance you stand away from the chart which is fixed at 20 feet. The denominator (bottom number) indicates the distance at which someone with normal eyesight could read the bottom line of the chart. Normal vision is therefore 20/20. If you’re 20/40 then the line you can correctly read could be read by a person with normal vision at 40 feet and it goes all the way up to 20/200 and after that you’re registered as blind.

Switching to metric, the equivalent of 20/20 is 6/6 (6 metres = 20 feet). Being 6/4 (actually 6/3.8) means I’m 20/12.5 on the old scale, the line marked 10 on the chart above. 6/3 is the best human vision can get (the bottom line on the chart, number 11). It’s rather exciting to think  I’m only 80 cm from ocular perfection!

Not sure? Then please don’t guess!

Last week, I witnessed an almighty sciencey cock-up. I was watching a live television programme with a usual audience in excess of 2.5 million and the presenter clearly stated that objects faller quicker to the earth because they weigh more. It was all to do with a Chilean base jumper using a motorcycle and in the VT, his bike noticeably fell quicker to the ground than he did.

When one of the presenters asked why that was, the other gave that explanation. As soon as the words left their mouth you could tell there was an element of doubt, anxiously looking to the others to bail them out. They duly did. ‘Urm, I’m not sure that’s correct’, one of them said. To which the original presenter cheerily said ‘any physics teachers out there, please tell us the correct answer!’.

But it was out there. Apparently that bike travelled quicker to the ground because it weighed more (a statement in itself which is incorrect- I doubt a dirt bike weighed more than a man?). Everyone heard it. Half an hour later when they revisited the base jumper story, they gave an answer from one of the listeners who correctly said objects with larger surface areas, like the base jumper, fall more slowly because they experience more air resistance. Acceleration depends upon force and mass. A larger mass has an inverse affect upon its acceleration. Over 400 years ago, Galileo dropped two different weights off the top of the Leaning Tower of Pisa to demonstrate this. Then astronaut David Scott recreated this on the moon with a feather and a hammer.

The presenters glossed over what happened half an hour earlier. But I heard it. My boyfriend heard it. I rang my parents and they’d heard it too, even saying when they revisited the story for a third time, they’d embellished it further with the David Scott story. So I wondered who else had heard it. I posted the following comment on Twitter to see,

According to @x on @y, objects fall slower because they weight [sic] less. Galileo might have something to say about that.

The presenter quickly replied,

@JoannaBuckley i didn’t say that!! that was sent in!

I challenged them once again,

@x Pretty sure you offered that as an explanation at 07.40 ish and then asked for ‘physics teachers to write in’ for help. No?

That was it, nothing more was exchanged. But I knew that comment wasn’t sent in by a viewer and, frankly, they’d just told me a bit of a porky.

I have a real problem with this. Not just the white lie but this is a sort of programme with a transitory audience. You probably wouldn’t watch the whole thing so if someone with little scientific understanding watched that segment at 07.40 and turned off sometime before 08.10, they’d have gone away thinking things fall quicker because they weigh more. That sort of mistake is akin to having me on BBC Question Time talking about government politics. I’d cock it up, I know I would so I wouldn’t even try. Don’t get me wrong, I’m all for giving stuff a go but science is based on empirical research. Testing, experimenting, observing, learning, exploring, advancing, gaining evidence to confirm a theory. An educated ‘guess’. Not a complete guess.

Sleep twitches and night hiccups

I am fascinated by things we do when we’re alseep that we’re not aware of, mainly because I am a very heavy sleeper. Apart from an earthquake, you name and and I’ve probably slept through it. That means I don’t have the foggiest idea what’s actually happening to my body when I’m asleep and I’m therefore a prime target for practical jokes. You can play human buckaroo with me and I’ll guarantee you’ll win.

It’s not just the normal things I sleep through either. Yes, I frequently fall asleep with the telly on like most folk. I also sleep through thunderstorms; through the crashing and rumbling I will not stir. I slept through a burglar alarm once. And, most strangely, I sleep through bouts of my own hiccups. That’s right, I hiccup during the night, on average probably once every couple of months and it’s left up to my boyfriend who woke with a fright to gently wake me and make me stop. Why am I such a heavy sleeper? Well I have more sleep spindles than you, if you consider yourself a light sleeper. Sleep spindles are sessions of increased brain activity when you’re alseep and they serve to keep you relaxed. Everyone passes through the same stages of sleep every night but deeper sleepers will have more of these spindles.

Aside from the night hiccups that you probably won’t be familiar with, I bet you’ve come across a certain feeling when you’re falling asleep- you think you’re falling and your whole body jerks when you think you hit the bottom. That’s a hypnagogic myoclonic twitch, essentially a muscle spasm.  The general consensus is that as your muscles begin to relax, your brain senses these signals and misinterprets them believing you’re falling.  Signals are sent to your muscles to get you out of trouble. You’re not alseep when this happens, it’s a sleepy daydream you’re experiencing. And, if you so desire, you can replicate the same sensation when you’re awake. Do anything that makes you fall backwards; stand at the bottom of your bed and lean backwards or lean back on your chair past the point of no return. In both cases, your body will fight to keep you upright and you’ll experience the same hypnagogic myoclonic twitch as when you’re relaxed. Go on, try it!