Sparkle sparkle

October 27, 2011 at 9:32 am | Posted in I didn't know that! | Leave a comment
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Sparkle sparkle

It’s that time of year again – no we’re not talking about Christmas – it’s Bonfire Night, and with it come various fireworks and sparklers.

I love a sparkler and I must admit to sulking like a little girl if I don’t get to write my name with one – but what are they actually made of? Continue Reading Sparkle sparkle…

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Hic…

September 29, 2011 at 10:18 am | Posted in I didn't know that!, Science Lite | Leave a comment
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Credit: admiller

We all get bouts of hiccups – squeeky little ones, or ones that come right from your boots that really hurt. Why we get them is a mystery, but what we do know is they can be really annoying – sometimes even embarrassing!

Most cases of hiccups occur for no apparent reason. Sometimes we get them after a few too many beers down the pub at lunch time, or if we’ve scoffed our dinner too quickly. But did you know hiccups can also be caused by shock, stress or excitement?

A sudden change in room temperature or the temperature inside your stomach can also cause hiccups.  Hiccups – or hiccoughs as they’re sometimes known – occur when your diaphragm suddenly and involuntarily contracts. This causes you to breathe air in very quickly, but this air is stopped by the glottis – the opening between your vocal cords – which closes suddenly, producing a hiccup!

So what’s the best way to get rid of them? Holding your breath, getting a fright, or drinking a glass of water backwards – yes…this task is particularly hard but by the time you’re done the hiccups have gone!

But what about those who have hiccups for long periods? They can be caused by a more serious underlying condition such as gastro-oesophageal reflux disease or inflammation of the stomach, throat ot thyroid gland. What can be done to rid them of the involuntary nightmare? The nastiest we read was puttingvinegar up the nose of a three year-old girl in Japan: it’s thought the vinegar helps stimulate the dorsal wall of the naopharynx where the pharyngeal branch of the glossopharayngeal nerve is located.

We’ll stick to drinking water backwards thanks!

Is π wrong?

July 28, 2011 at 1:15 pm | Posted in I didn't know that! | Leave a comment
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Should Tau replace Pi?

Everyone knows the circumference of a circle is πd, while the area equals πr2, but what if π is wrong?

In 2001, mathematician Bob Palais from the University of Utah first argued that π was wrong. Although the physical number – 3.14159 – is not wrong, Palais argues that, when it comes to circles mathematicians had been focussing on the wrong number.

He states that Tau – 6.28318 or the ratio of a circle’s circumference to its radius – is the truly sacred number of the circle, and that it might even make maths simpler.

Using τ is a much more natural number to use in geometry, trigonometry and even advance calculus agrees Kevin Houston from the University of Leeds. He argues that a quarter of a circle corresponds to half of π, and three quarters to three halves of π, but three quarters of a circle also equals three quarters of τ – a fact might help students from making ‘silly errors’.

It might be easier, but is π too ingrained in our society for it to be replaced? It has become and integral part of our lives -ask anyone what the area of a circle is and they’ll say πr2 – we had that drummed into our heads from an early age and it’s not something we’re likely to forget! But maybe as the τ movement gains pace, we’ll be hearing our children and grandchildren reciting equations with τ instead.

Rock, paper or scissors?

July 26, 2011 at 12:44 pm | Posted in I didn't know that!, Science Lite | Leave a comment
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What’s my first move – rock, paper or scissors? Most people go for scissors, so I’ll pick rock, but what if you do the same and go for rock? I’ll go for paper…but then I might lose…

It’s the same old problem, just which hand shape do you choose to make sure you beat your opponent? New research suggests it doesn’t matter what you choose as you’re more likely to copy your opponents hand shape anyway.

Researchers from UCL recruited 45 participants to play rock-paper-scissors in one of two conditions – both players blind-folded, or just one player blindfolded. Players winning the most games in a 60 game match got a financial reward, so winning the game really was the best option.

In the blind-blind condition, exactly a third of games ended in a draw – exactly what was expected. But in the blind-sighted games, the number of games ending in a draw was higher, suggesting the sighted player copied the blindfolded one. Researchers think this automatic imitation is mediated by the human mirror neuron system, a network of brain regions responsible for action execution and which responds to passive observation of actions.

“It is well established that imitative responses are executed faster than non-imitative responses on controlled experimental task where reaction times average between 200-400ms,” said Richard Cook from the department of cognitive, perceptual and brain science. “However, the present finding confirms that imitation is often ‘automatic’ in the sense of being hard to stop.”

So outwitting your opponent isn’t really an option – we’re likely to copy whatever hand shape they make because we just can’t stop ourselves.

Hold your nose, close your mouth and breathe…

June 8, 2011 at 9:31 am | Posted in I didn't know that! | Leave a comment
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It sounds almost impossible – hold your nose, close your mouth and then try to breathe – but we all do it when we have the hiccups or need to make our ears pop. This forceful attempted exhalation against a closed airway is known as the Valsalva manoeuvre.

I’d never really given the action any thought before, let alone that it might have a name! I was reading Inflight Science: A Guide to the World from your Airplane Window when I came across the term and thought it only right that I find out more.

Apparently the technique is named after Antonio Maria Valsalva, a 17th Century physician and anatomist from Bologna. His speciality was the human ear and he described this manoeuvre to expel pus from the middle ear.

When diving or taking off in an airplane, we feel that our ears need to pop because there is an unequal pressure across the eardrum caused by a pressure increase. People are advised to swallow – or if on a plane, suck a boiled sweet – but if that fails to work they’re advised try the Valsalva manoeuvre.

When exercising or weight lifting, you can sometimes perform the Valsalva manoeuvre without even realising. Air gets trapped and pressurised in the lungs, and blood pressure rises, forcing blood out of the pulmonary circulation into the left atrium. Pressure inside the chest prevents blood that has been circulating around the body getting back into the heart, and the output of the heart is reduced. When you finally breathe, the pressure on the chest is released, the pulmonary vessels and aorta re-expand and venous blood enter the chest and the heart, cardiac output begins to increase. The Valsalva manoeuvre can cause dizziness and fainting – that’s why you’re always told to breathe normally when exercising.

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