Reblogged from Sciencegirl:

A study to be published in next month’s American Journal of Cardiology has confirmed that earlobe creases are associated with coronary artery disease. This research upholds the findings of several other studies, including a 2006 Swedish study, which showed that earlobe creases as a marker for heart disease had a positive predictive value of 80% in people under 40 years old.

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Reblogged from Sciencegirl:

Since becoming a public company, Facebook shares have dropped by 29%, reducing their intial market value by US$30 billion over the last month.

The website generates most of its revenue from advertising but a recent survey indicates that four out of five Facebook users have never bought a product or used a service as a result of Facebook banner ads.

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Reblogged from Sciencegirl:

For the last few decades the mainstream press have extolled the virtues of moderate red wine consumption, particularly the possible cardioprotective benefits of resveratrol, found in the skin of red grapes. Sales of red wine have increased dramatically as the masses have embraced the notion of ‘healthy’ drinking but it seems only those truly appreciating the wine reap the cardioprotective benefits.

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The Acceleration Phase (0-30m)

Unfortunately for Bolt, the sprint start and the acceleration phase account for 64% of the total result in the 100m dash. This creates a major disadvantage for taller sprinters, who are often poor starters.

Bolt’s reaction times are generally much slower than the 0.1s allowed and physics noticeably hampers him during the acceleration phase.

The Physics:

The acceleration is proportional to the force produced when pushing off the blocks but there is an inverse relationship between acceleration and body mass.

This means that height is a disadvantage because the force also has to overcome the drag produced by a bigger body.

Sprinters with well-developed, strong muscles attached to shorter limbs promote more rapid movements and a greater force, which gives them an initial advantage.

Maximum Velocity Phase (30-60m)

During this phase the runners are upright, well away from the blocks and are attempting to reach their top speed, which is achieved through a combination of stride length and stride rate.

This is where a taller sprinter has the potential to catch up – long limbs and good flexibility alone achieve half of the speed formula.

Bolt’s gangly limbs suddenly become an advantage, meaning he can reach 44km/h during this phase and can pull ahead, despite his poor start.

It also explains why Bolt does not achieve the same kind of success in the 60m dash as he does at longer sprint races: he is still catching up at the beginning of this phase!

Speed Maintenance Phase (60-100m)

The final phase is all about speed maintenance and Bolt himself has stated that if he is ahead at 60m, the other contenders simply don’t stand a chance.

Bolt is able to maintain his pace exceptionally well and in the Olympic 100m final Bolt completed the race in just 41 steps, compared to Blake’s 46 steps.

In the 200m final Bolt’s poor start will be even less of a factor…Thursday 9^th at 8.55pm BBC1

Elastic energy!  For those who’ve forgotten their school physics –or never paid attention!-  elastic energy is potential mechanical energy that can be stored when work is performed to stretch or compress an object or physical system.

How does the frog do it?

As a frog prepares to leap, the calf muscle shortens and pulls on the tendon, which is wrapped tightly around the ankle bone.  After a fraction of a second the calf muscle stops moving and the energy is fully loaded onto the stretched tendon. When the frog jumps, the elastic energy is released like a catapult, propelling the frog forward!

Frog fact: Frogs can jump amazing distances -in some cases up to 50 times their body length, which is the equivalent to a human jumping the length of a football field from a standing position!

How does the archer do it?

The archer creates the elastic potential by drawing the bowstring back, changing the configuration of the bow. The force is stored in the distorted shape until the archer decides to release the bowstring, just as the energy is stored in the frog’s tendon until it decides to leap! The arrow is then propelled at a much greater speed than muscles alone could achieve, projecting the arrow much further.

Archer fact: Archers competing in the London Olympics will be aiming their bows at targets approximately 70m away, a distance impossible to reach if they relied on the kinetic energy of the muscles.

Why are red blood cells so important?

Red blood cells, or more specifically the haemoglobin (Hb) protein of the red blood cell, binds oxygen in the lungs and carries it to muscles throughout the body.  One of the major limiting factors in endurance exercise is oxygen delivery to the working muscles. The more oxygen carrying capacity an athlete has, the better the athlete’s endurance.

How do scientists detect the use of EPO?

The volume of the red cell population in the blood is known as the haematocrit (HCT) and is normally between 41-50% in men, and 36-44% in women. Haemoglobin concentration can also be measured and should fall between 14-17g/dL in men, and 12-15g/dL in women. If blood tests detect high HCT or Hb values, it can indicate the use of EPO. Occasionally, athletes have naturally high HCT or Hb measurements, so testing over extended time periods is essential to determine exceptional values for the individual athlete.

The dangers of EPO doping

Excessive use of EPO can make blood more viscous; putting a strain on the heart muscles and has in many cases led to heart failure. The sport probably most associated with EPO is cycling but many endurance sports including rowing, distance running, triathlons and horseracing have had their fair share of scandal.

The International Olympic committee (IOC) define drug doping as the use of any method or substance that might harm the athlete, in a quest to gain an unfair advantage over their fellow competitors.

What methods are used?

Typically, cheats use performance enhancing drugs or blood doping. The performance enhancing drugs are usually stimulants, which increase alertness and physical activity, or steroids, which increase muscle mass. Blood doping involves undergoing a blood transfusion in order to acquire a higher red blood cell count, allowing extra oxygen to be carried to the muscles.

How are drug cheats caught?

Two urine samples are obtained from athletes and analysed using gas chromatography (which separates the contents of the sample) and mass spectrometry (which provides the exact molecular specification of the compound). If a banned substance is identified in both samples a positive result is declared.

Blood testing is also used to detect banned substances and to build a ‘blood profile’ over time for an individual athlete. This is used to determine average readings for the athlete and any significant changes that could indicate blood doping.

What’s so special about London 2012?

For the first time, a private sponsor -GlaxoSmithKline (GSK)- will be providing what are considered to be the most hi-tech laboratory facilities in Olympic history, at a cost of more than $30 million. GSK will test over 6,250 samples of blood and urine during the London Olympics, compared to 4,500 in Beijing, and 150 scientists will be on duty around the clock.

London 2012 could be the cleanest games ever. Keep Britain Tidy!

What is a false start?

Scientific research has shown that a reaction time faster than one tenth of a second is impossible for a human, so a false start is defined as a reaction that occurs within this time after the gun has fired.

How is it detected?

At the 2012 London Olympics, Omega will be unveiling a brand new starting block to measure the runners’ reaction time. The blocks measure the pressure exerted by a runner’s feet and relays this to a computer, which also measures the time from the firing of the pistol to one tenth of a second later. If an increase in the pressure exerted by the feet is detected during that split second, a false start is declared.

How is this relayed to the starter?

The starter will then receive a signal from the computer via an earpiece and will fire the gun again to alert the runners to the false start. Checks will be made to ensure no technical malfunctions occurred before a false start is officially declared.

What’s so special about the new Omega technology?

The new Omega blocks have incorporated the Quantum Timer and Quantum Aquatic Timer, which can achieve a resolution of one millionth of a second, 100 times more accurate than the previous technology used.

Legionella pneumophila

Once the bacterium has entered the body it invades cells called macrophages. Macrophages are cells of the immune system which normally scavenge cells debris and engulf invading pathogens so they can be destroyed by other cells.

The Legionella pneumophila bacterium, however, is able to replicate itself inside the macrophage instead of being destroyed.

The bacterium is transmitted via tiny airborne droplets that are released when water is disturbed and are then inhaled into the lungs.

The most common sources are cooling towers (suspected to be the case in the current Scottish outbreak), ice machines, hot-tubs, showers, air conditioning systems and any complex potable water system or cooling system.

Once infection has taken hold (between 2-10 days), the immune response initially causes fever, chills, muscle aches, headaches and a cough, similar to flu symptoms.

More serious consequences of infection include kidney and liver damage. Middle aged, elderly people, smokers, and patients with chronic lung conditions have an elevated risk of contracting the disease.

Antibiotics that have good intercellular penetration are most effective against the bacterium, such as tetracyclines or erythromycin.

The website generates most of its revenue from advertising but a recent survey indicates that four out of five Facebook users have never bought a product or used a service as a result of Facebook banner ads.

The poll also revealed that 34% of Facebook users are spending less time on the site, and the increasing use of smartphones by current Facebook users to access accounts is further stifling advertising potential.

Facebook Fatigue?

In 2008, Facebook finally overtook rival My Space to become the top social networking site -measured by number of monthly unique visitors- and currently boasts 900 million members. However, Facebook are struggling to turn this customer base into advertising revenue and to keep users interested. Are we finally tiring of what has become one of the most popular online destinations?

The latest attempt to combat Facebook fatigue, by introducing ‘Timeline’, was met with widespread discontent. Recent scandal (see below) and the fact that approximately 50% of employers have completely banned Facebook in the work place are turning users off, and sales growth is slowing.

Facebook Feuds

One of Facebook’s main competitors for online advertising is the search engine Google, who were hit by a major smear campaign in 2011 regarding privacy policies. The anti-Google campaign was orchestrated by major PR company Burson-Marsteller, and it was later discovered that they had been paid by Facebook.

The social network was at the centre of yet more scandal in November 2011 when private accounts were hacked and pornographic images were displayed in user profiles. That same month Facebook settled charges that it had deceived customers by failing to keep privacy promises.

The poll also reported that 21% of those surveyed do not have a Facebook account and the reasons given for the reduction in Facebook use were that the site was ‘boring’, ‘not relevant’ or ‘not useful’. These views are likely to become more widespread if Facebook do not put their house in order.