According to a recently published study, people who only get six or seven hours of sleep have longer life (26)_______ than those who sleep eight or more hours. “The idea that we need eight hours of sleep is completely unscientific,” said Professor Daniel Kripke, who led the study. The methods used, (27) _______ , have been criticised. Investigators relied on people's own accounts of how long they slept, (28) _______ could be rather imprecise, as no one really knows when they fall asleep.
Contrary to Professor Kripke's findings, (29) _______ experts believe that getting insufficient sleep is a serious problem. What all scientists agree on is that more research is needed to discover exactly what the relationship is between sleep and longevity. This research is essential because with all the (30) _______ of modern life, such as cable TV and the Internet, it seems that a good night's rest is becoming increasingly rare.

Going to the gym or the sports centre often feels like a joyless necessity. The sweaty rooms and irritating music seem to be part of the price you pay for getting fit. In actual fact, your exercise routine will have some bad side-effects and we don't just mean aching muscles! Gyms and sports centres need huge amounts of energy for lights, air conditioning, heating - and of course, pools and machines.
Luckily, there's now another way for people who care about more than calorie-counting. Green Fitness allows you to exercise in the open air, surrounded by birdsong. What's more, rather than destroying the planet, you'll be helping to preserve it. How? By doing conservation work in some of the most beautiful parts of the country.
If you've never done any gardening before, don't worry. We'll give you all the training you need. Volunteers cooperate to achieve tasks together, so you won't be on your own. The team spirit is amazing- something which you're never going to find at the gym! What's more, many volunteers have reported that taking part in sessions has boosted their self-esteem and happiness. However, this is not a 'soft' alternative and laziness is not an option! An hour's moderate gardening is at least as demanding as a six-kilometre jog and builds strength in all parts of your body.

Welcome to Nunavik - a beautiful landscape of forests, blue skies and clear waters. You might think that Nunavik's geographical position at the ends of the Earth keeps it safe from big city problems like air and water pollution.
Unfortunately, the pretty villages of Nunavik have not escaped the problems that the rest of the world is facing, too. Some years ago, scientists made a worrying discovery. An extremely dangerous group of chemicals known as 'persistent organic pollutants' (or POPs) were attacking the Arctic environment. POPs are used everywhere - in TVs, in lights and in paint. They are also sprayed onto crops as pesticides. Over time, they become gas and go into the air, and the wind carries them thousands of kilometres.
POPs can cause cancer and allergies, as well as other damage. They can also cause developmental problems in babies and children. Clearly, something had to be done about the problem and so in the 1990s, the United Nations held a meeting called the Stockholm Convention to discuss banning lots of the POP chemicals. Since then, many countries have agreed to start producing fewer POP chemicals, and as a result, levels of POPs in the Arctic are falling.
It will take many years for the problem to go away. For one thing, buildings around the world still have many tons of POPs in their paint and wiring. For all the people and animals in the Arctic regions, their only hope is the work of scientists and the help of the rest of the world in putting an end to POPs once and for all.