Fear may be felt in the heart as well as in the head, according to a study that has found a link between the cycles of a beating heart and the chance of someone feeling fear.

    Tests on healthy volunteers found that they were more likely to feel a sense of fear at the moment when their hearts are contracting（收缩）and pumping blood around their bodies, compared with the point when the heartbeat is relaxed. Scientists say the results suggest that the heart is able to influence how the brain responds to a fearful event, depending on which point it is at in its regular cycle of contraction and relaxation.

    Sarah Garfinkel at the Brighton and Sussex Medical School said: “Our study shows for the first time that the way in which we deal with fear is different depending on when we see fearful pictures in relation to our heart.”

    The study tested 20 healthy volunteers on their reactions to fear as they were shown pictures of fearful faces. Dr Garfinkel said, “The study showed that fearful faces are better noticed when the heart is pumping than when it is relaxed. Thus our hearts can also affect what we see and what we don't see and guide whether we see fear.”

    To further understand this relationship, the scientists also used a brain scanner（扫描仪）to show how the brain influences the way the heart changes a person's feeling of fear.

    “We have found an important mechanism by which the heart and brain ‘speak' to each other to change our feelings and reduce fear,” Dr Garfinkel said.

    “We hope that by increasing our understanding about how fear is dealt with and ways that it could be reduced, we may be able to develop more successful treatments for anxiety disorders, and also for those who may be suffering from serious stress disorder.”

    The following is a selection of the 2017 summer programs offered at colleges and universities around the world．

    Many of us love July because it's the month when nature's berries and stone fruits are in abundance. These colourful and sweet jewels form British Columbia's fields are little powerhouses of nutritional protection.

    Of the common berries, strawberries are highest in vitamin C, although, because of their seeds, raspberries contain a little more protein (蛋白质), iron and zinc (not that fruits have much protein). Blueberries are particularly high in antioxidants (抗氧化物质). The yellow and orange stone fruits such as peaches are high in the carotenoids we turn into vitamin A and which are antioxidants. As for cherries (樱桃), they are so delicious who cares? However, they are rich in vitamin C.

    When combined with berries of slices of other fruits, frozen bananas make an excellent base for thick, cooling fruit shakes and low fat “ice cream”. For this purpose, select ripe bananas for freezing as they are much sweeter. Remove the skin and place them in plastic bags or containers and freeze. If you like, a squeeze of fresh lemon juice on the bananas will prevent them turning brown. Frozen bananas will last several weeks, depending on their ripeness and the temperature of the freezer.

    If you have a juicer, you can simply feed in frozen bananas and some berries or sliced fruit. Out comes a “soft-serve” creamy dessert, to be eaten right away. This makes a fun activity for a children's party; they love feeding the fruit and frozen bananas into the top of the machine and watching the ice cream come out below.

    A team of international scientists is due to set off for the world's biggest iceberg in a mission aiming to answer fundamental questions about the impact of climate change in the polar regions. The scientists, led by the British Antarctic Survey (BAS), are trying to reach a newly revealed ecosystem that had been hidden for 120,000 years below the Larsen C ice shelf.

    Last year, part of the Larsen C ice shelf calved (崩解) away, forming a huge iceberg-A68—which is four times bigger than London, and revealing life beneath for the first time. Now scientists say it is a race against time to explore these new ecosystems before they are transformed to the light. Marine biologist Dr Katrin Linse from the BAS is leading the mission.

    "The calving of A68 provides us with a unique opportunity to study marine life as it responds to a huge environment change," she said. "It is important that we get there quickly before the undersea environment changes as sunlight enters the water."

    Professor David Vaughan, science director at the BAs, said, "We need to be bold (大胆的) on this one. Larsen C is a long way south and there's lots of sea ice in the area, but this is important science, so we will try our best to get the team where they need to be. He said climate change had already affected the sea around Antarctica and is warming some coastal waters. "Future warming may make some habitats warm. Where these habitats support unique species that are adapted to love the cold and not the warm, those species are going to either move or die."

    There is growing concern about the possible impact of climate change in the Antarctic. Earlier this month, a report revealed that melting ice sheets in Greenland and Antarctica are speeding up the already fast pace of the sea level rise. The research, published by the National Academies of Science, Engineering and Medicine, said, "At the current rate, the world's ocean will be, on average, at least 60cm higher by the end of the century." However, it found that the process is accelerating, and more than three quarters of the acceleration since 1993 is due to melting ice sheets in Greenland and Antarctica, the study shows.

    Elephants have impressed us for centuries. They are big, clever, and sociable. But what if someone told you that they may also hold the key to fighting cancer (癌症)?

    People have been wondering why elephants do not develop cancer, even though they have lifespans (寿命) that are similar to humans, living for around 50 to 70 years.

    Now scientists believe they know why. A team at the University of Chicago, US has found that elephants carry a large number of genes that stop tumors (肿瘤) from developing. To be precise, they found 20 copies of an anti­tumor gene called TP53 in elephants. Most other species, including humans, only carry one copy.

    According to the research, which was recently published on the online science network BioRxiv, the extra copies of the gene improved the animal's sensitivity to DNA damage. This lets the cells quickly kill themselves when damaged before they can go on to form deadly tumors.

    “An increased risk of developing cancer has stood in the way of the evolution of large body sizes in many animals，” study author Dr. Vincent Lynch told The Guardian. If every living cell (细胞) has the same chance of becoming cancerous, large creatures with long lifespans like whales and elephants should have a greater risk of developing cancer than humans and mice do. But across species, the risk of cancer does not show a connection with body mass.

    This_phenomenon was found by Oxford University scientist Richard Peto in the 1970s and later named "Peto's paradox". Evolutionary (进化的) biologists believe it results from larger animals using protection that many smaller animals do not. In the elephant's case, the making of TP53 is nature's way of keeping this species alive.

    The study also found that when the same genes were brought to life in mice, they had the same cancer resistance (抵抗) as elephants. This means researchers could use the discovery to develop new treatments that can help stop cancers from spreading or even developing in the first place.

    "Nature has already figured out how to prevent cancer, " said Joshua Schiffman, an oncologist at the School of Medicine, University of Utah, US.

    “It's up to us to learn how different animals tackle (处理) the problem so we can use those strategies to prevent cancer in people.”

    We talk a lot in the U.S. about success. Success is the dream and the end point. And not by coincidence the idea that hard work leads to personal success is as American as apple pie.

    But the reality is that sometimes we fail. And sometimes things, through no fault of our own, don't go our way. We're faced with a life-changing diagnosis (诊断), the passing of a loved one or job loss. We don't, as a society, have as much to say here.

    I think uncertainty does us all harm. We'd feel better equipped to deal with uncertainty if we talked about it more. I had so fully bought into the belief that with enough effort, I could control what happened in my life. I actually caught myself thinking I could "work my way out" of my cancer. As it turns out, cancer doesn't really care about one's work.

    We might also make wiser decisions — this isn't just a feel-good exercise. For example, technology and medicine have progressed to the point that many patients are living longer than they would have even a decade ago. These are achievements worth celebrating. And yet I wonder if the focus on success is sometimes misguided here as well. If it is one reason why we tend to pursue expensive end-of-life treatments, they often accomplish little other than to make a patient's final days painful and frightening. The fact is that, when asked, many patients would rather focus on living meaningfully in their final days.

    My hope here is to make a case for thinking about meaning, in the same way we think about pursuing success. In that spirit, I've asked several people, each of whom has met misfortune, how they find meaning in their lives. The diversity in their responses reflects the fact that there are no right or wrong answers here. We each can find meaning in different things.