【推荐1】As the development of computer, people count on computer so much, now most businesses are done online, trading online saves people a lot of time and it is very convenient. As more and more people choose to shop online, there comes the relative services, the most important one is express deliver.

Many years ago,express deliver is not that popular, now it becomes the main tool for people to receive online products. Express deliver is very fast, the companies make the promise that the customers can get their products in three days. Many years ago, people can get their things in a week, now express deliver shorten the time. What’s more, the express deliver can deliver the products to the customers' homes, people don’t have to go out, how convenient it is. I like to use express deliver, it facilitates my life and saves me a lot of time.

【推荐2】In today’s youth culture, it seems as if teens are permanently glued to their cellphones, constantly receiving beeping, buzzing and blinking social media notifications (通知). We often hear of the harm of social media to teens and young people, but our latest research on young girls and boys has revealed that social media is not always negative.

In some cases, we found that social media can positively influence their health and well-being, by helping them learn about healthy eating or new workouts to try. Besides, social media provides space for young people to talk to each other about issues of health.

For our study, conducted by researchers from the University of Birmingham and Orebro University, we invited over 1,300 young girls and boys, aged 13-18, from ten UK schools. We were interested in better understanding how young people use social media, and how they feel it impacts their health and well-being. To do this, we selected 84 participants from the main sample and had them take part in small group interviews.

The results showed that social media often had a positive influence on young people’s motivation for being physically active and on their ability to make conscious diet choices. Social media also allowed them to access the information they found inspirational, and learn about different apps they could use to be physically active or monitor their progress. They reported that likes, comments, and views on their social media posts also helped them stay motivated to exercise.

Encouragingly, the young people we spoke to were also highly discerning users of social media. They thought carefully about the content they were engaging with online. For instance, the teenagers reported that they would often ignore content that had the potential to lead to harm, such as images or videos that presented unrealistic workouts or expectations for their bodies.

While the risks should certainly not be overlooked, our findings show that social media can have a positive effect on young people’s health and well-being. A benefit of social media is that it provides real-time, low-cost information, and support from their peers. Making young people use social media safely, critically and responsibly may thus help them continue to lead a healthy life.

【推荐2】Cancer is caused by gene mutations (突变) that accumulate in cells over time, yet long-lived animals that have lots of cells, such as elephants and whales, hardly ever get it. Why?

For elephants, at least, part of the answer may be the gene commonly known as p53, which also helps humans and many other animals repair DNA damaged during replication (复制). Elephants have an amazing 20 copies of this gene. Those copies, each with two variations produce a total of 40 proteins, compared with humans’ (and most animals’) single copy producing two proteins.

In mammals, p53 plays a crucial role in preventing mutated cells from turning into tumors (肿瘤). It works by pausing replication and then either initiating repair or causing cells to self-destruct if the damage is too extensive. Without action from p53, cancer can easily take hold: in more than half of all human cancers, the gene’s function has been lost through random mutations.

The scientists virtually modeled and studied carefully elephants’ 40 p53 proteins, finding two ways the gene could help elephants avoid cancer. First, the fact that elephants possess multiple copies lowers the chance of p53 no longer working because of mutations. Additionally, elephants’ p53 copies activate in response to varying mutations and so respond to damaged cells differently, which likely gives an edge when detecting and getting rid of mutations.

These “remarkable” results imply that elephants have a series of means though which p53 can operate, says Sue Haupt, a cell biologist who was not involved in the work. This points to “exciting possibilities for exploring powerful new approaches to cancer protection in humans,” she adds.

Study co-author Robin Fahraeus and his colleagues are now following up on these results using blood samples from an African elephant at the Vienna Zoo. They are exploring how its p53 proteins interact with damaged cells and plan to compare those findings with results from human cells.