Fishermen have been warned to look out for a"killer shrimp(虾)"，an invasive(侵人的) species that is spreading across the UK and is endangering native fish species.

The aggressive shrimp, which often kills its prey(猎物) and leaves it uneaten, is originally from eastern Europe, but it is now found in lakes and rivers across the UK. The shrimp attacks insects, baby fish and native shrimp, threatening fish species and damaging the food chain. The spread of the shrimp is blamed on fishing on open waters using floating tyres, as the baby shrimp attach themselves to the bottom of the tyres and are transported to new waters. .

The UK Environment Agency is so concerned about the spread of the invasive species that it launched a campaign to warn their equipment between fishing trips. United Utilities is the first water company to ban the use of floating tyres at all its recreational (娱乐的) waters across the northern coast of the UK. The staff at the company are working closely with the Environment Agency and fishing clubs that have licenses to fish on their protected waters.

"Despite the horrible name, the shrimp are not a threat to people, but the damage they could cause to the environment on the northern coast is very serious," said Bryan Homan, manager of the water company. "Because of what they eat and the rate that they eat, the shrimp can change the food chain and the ecosystem, threatening native fish species."

A spokesman from the Environment Agency added, "We are encouraging all fishermen who go fishing on open waters to help us prevent the spread of the shrimp by sluicing all fishing equipment before and after use."

United Utilities and the Environment Agency believe that it is in fishermen's interests to stop the spread of the shrimp.

When a friend comes to you after a stressful day, how do you comfort him? Do you let him complain? Do you pour him a glass of coffee? Those could work. But a new study finds that a very effective technique is also simple and easy—hugging.

"Individuals who reported noticing the availability of a network of supportive individuals tend to show better adaptation when faced with stress. But just because you have a support network does not mean that you absolutely feel that support," said Michael Murphy, a psychology expert at Carnegie Mellon University in Pittsburgh. He wanted to know if people who received hugs regularly could handle anxiety and stress better.

So Murphy and his team interviewed 404 men and women every evening for two weeks, During these interviews, the participants were asked a simple yes or no question -whether somebody had hugged them that day-and a simple yes or no question of whether they had experienced conflict with somebody that day. They also were asked to respond to questions about negative and positive mood states.

And the researchers found that people who experienced a conflict were not as negatively affected if they received a hug that day as participants who experienced conflict and didn't get a hug. And they were also found not to carry the negative effect to the next day, while those who did not receive one would. The findings are in the journal PLOS ONE.

Murphy does include this warning: "So our findings should not be taken as proof that people should just start hugging anyone and everyone who seems upset. A hug from one boss at work or a stranger on the street could be viewed as neither agreeable nor positive." The idea is to relieve stress. Not add to it.

When instant cake mixes first appeared in the 1950s, American housewives were doubtful. These mixes, promising easy cake-baking, felt too easy. The manufacturers discovered that requiring the addition of an egg in the baking process was just enough to make the housewives happy with their work. The greater sense of effort gained from a little extra labor is believed to have been essential to the later success of the cake mix. 

This reflects the IKEA effect (宜家效应), which is identified by psychologist Michael I. Norton and his colleagues, suggesting we place greater value on things we have worked to create. They conducted four studies in which they asked participants to fold paper cranes and frogs, assemble IKEA boxes, and build sets of Legos. They then asked the builders to bid (出价) for their creations, and compared the prices with bids from people who hadn't built them. The builders consistently outbid the non-builders. 

Interestingly, the IKEA effect works even when people have no opportunity to fully personalize their creations. While most participants' folding skills left much to be desired, they loved their imperfectly personalized products all the more. Builders valued their wrinkled crane-like creations nearly five times as much as non-builders. Beauty, it seems, is in the eye of the builder.

Today, as cities are suffering from severe housing crises, the IKEA effect can give us insight into the well-being benefits of a self-building approach to housing development. Projects like WikiHouse and the "half-a-house" approach pioneered by Alejandro Aravena's architecture company Elemental are working to make housing more affordable and sustainable by making it easier for people to build and personalize their own homes. 

"The moment people are involved with their built environment, they have a totally different relationship to it," WikiHouse co-founder Alastair Parvin explained. "When the roof starts leaking or a door starts creaking, they have the power to fix it themselves."