In recent years,stressed-out people living in cities have been seeking protection in green spaces for the proven positive impacts on physical and mental health,but the benefits of"blue space"-the sea and coastline,but also rivers,lakes,canals,waterfalls,even fountains-are less well advertised, yet the science has been consistent for at least a decade:being by water is good for body and mind.

＂Many of the processes are exactly the same as with green space-with some added benefits," says Dr Mathew White,a senior lecturer at the University of Exeter.

White says there are three established pathways by which the presence of water is positively related to health and happiness.First,there are the beneficial environmental factors,such as less polluted air and more sunlight.Second,people who live by water tend to be more physically active. Third-and this is where blue space seems to have an advantage over other natural environments-water has a psychological recovery effect.When you are sailing,surfing or swimming,says White,＂you're really in step with natural forces there."

Catherine Kelly is a wellness practitioner who teaches classes in"mindfulness by the sea”.She says the sea has a quality that can make people thoughtful.

＂To go to the sea means letting go,"says Kelly."It could be lying on a beach or somebody handing you a cocktail.For somebody else,it could be a wild,empty coast.But there is this really human sense of:'Oh, look,there's the sea-and the shoulders drop."

The Nazca Lines are a collection of giant geoglyphs (地画), located in the Peruvian coastal plain about 250 miles south of Lima, Peru. Created by the ancient Nazca culture in South America, the 2, 000 ­year ­old Nazca Lines can only be fully viewed from the air given their massive size.

There are three basic types of the Nazca Lines: straight lines, geometric designs and pictorial (图画的) representations. More than 800 straight lines are found on the coastal plain, some of which are 30 miles long. Additionally, there are over 300 geometric designs, which include basic shapes such as triangles, rectangles, as well as arrows, zigzags and wavy lines. The Nazca Lines are perhaps best known for the representations of about 70 animals and plants, some of which measure up to 1, 200 feet long. Examples include a spider, hummingbird, monkey, whale, dog, duck, flower, and tree.

More recent research suggested that the Nazca Lines’ purpose was related to water, a valuable thing in the desert. The geoglyphs weren’t used as an irrigation system or a guide to find water, but rather as part of a ritual (仪式) to pray to the gods — an effort to bring much­ needed rain.

The Nazca Lines are located in the desert plains of the Rio Grande de Nasca river basin. The desert floor is covered in a layer of deep red color rocks. The ancient people created their designs by removing the top 12 to 15 inches of rock, revealing the lighter-colored sand below. They likely began with small­ scale models and carefully increased the models’ proportions (规模) to create the large designs.

Given the small amount of rain, wind and erosion in the desert, the geoglyphs have remained largely unharmed throughout the centuries. But the geoglyphs aren’t completely safe. In 2009, the Nazca Lines suffered the first recorded rain damage. Five years later, the environmental group Greenpeace damaged an area near the hummingbird geoglyph during a media stunt.

While it may sound like something that has come out of your nightmares, cyborg cockroaches (蟑螂机器人) have arrived as friends rather than enemies.

Scientists in Japan have designed a new remote-controlled insect, equipped with a battery “backpack” that is powered by solar panels. The cockroach, which is part insect and part machine, is intended to enter dangerous areas, monitor the environment or undertake search and rescue missions without needing to be recharged. The researchers from the RIKEN Cluster for Pioneering Research had to install some items into a tiny pack to allow for all the cockroach’s natural movements.

Being able to survive the tough conditions, cockroaches, the ancient insects, have been the stimulus for a number of technologies in recent years. Therefore, different teams of scientists have designed various remote controlled robo-bugs (机器虫) that can climb walls, carry objects and find humans during search-and-rescue missions.

Previously, wires were attached to the cyborg cockroach’s two sensory organs to send electrical signals that caused the “insect” to move right or left. A battery was necessary for the sending and receiving of these electrical signals, which needed to be charged up.

So the RIKEN team wanted to create a more practical one. Finally, they designed an on-board solar cell that could continuously ensure that the cockroach stayed charged while it worked. The solution was to design a special “backpack” that could neatly carry both the wireless leg-control module and rechargeable battery. This was attached to the top of the insect, and was 3D printed to fit perfectly to the surface of the cyborg cockroach. It allowed this electronic device to be firmly fitted on the “insect” for over a month.