People may form inaccurate impressions about us from our social media posts, finds new Cornell University research that is the first to examine perceptions (认知) of our personalities based on online posts.

An analysis of online status updates found great difference between how viewers saw the authors across a range of personality traits, and the authors’ self-perceptions.

Viewers rated the Internet users on average as having lower self-esteem and being more self-revealing, for example, than the users rated themselves, Status updates containing photos, videos or links in addition to text facilitated more accurate assessments than those with just text the researchers found.

Overall, they said, the study sheds light on the dynamic process by which a cyber audience tries to make sense of who we are from isolated fragments (碎片) of shared information, jointly constructing our digital identity.

“The impression people form about us on social media based on what we post can differ from the way we view ourselves.” said Qi Wang, professor of psychology and director of the Culture &. Cognition Lab. “A mismatch between who we are and how people perceive us could influence our ability to feel connected online and the benefits of engaging in social media interaction.”

The Cornell researchers believe their study is the first to investigate audience perceptions of social media users through their posts, On platforms, users often share fragmentary personal narratives while interacting with “friends” they may know only a little or sometimes not at all.

Interestingly, the study found that online status updates generated perceptions of users that were consistent with cultural standards in offline contexts concerning gender and ethnicity—even though viewers were blind to their identities.

Wang said the findings could help developers design interfaces that allow people to express themselves most authentically.

“If people’s view of us is very different from who we actually are, or how we would like to be perceived.” Wang said, “it could harm our social life and well-being.”

By the end of the century, if not sooner, the world’s oceans will be bluer and greener thanks to a warming climate, according to a new study.

At the heart of the phenomenon lie tiny microorganisms (微生物) in the ocean called phytoplankton. Because of the way light reflects off the organisms, these phytoplankton create colorful patterns at the ocean surface. Ocean color varies from green to blue, depending on the type and concentration of phytoplankton. Climate change will fuel the growth of phytoplankton in some areas, while reducing it in other spots, leading to changes in the ocean’s appearance.

Phytoplankton live at the ocean surface, where they pull carbon dioxide into the ocean while giving off oxygen. When these organisms die, they bury carbon in the deep ocean, an important process that helps to regulate (调控) the global climate. But phytoplankton are vulnerable to the ocean’s warming trend. Warming changes key characteristics of the ocean and can affect phytoplankton growth, since they need not only sunlight and carbon dioxide to grow, but also nutrients.

Stephanie Dutkiewicz, a scientist in MIT’s Center for Global Change Science, built a climate model that projects changes to the oceans throughout the century. In a world that warms up by 3C, it found that multiple changes to the color of the oceans would occur. The model projects that currently blue areas with little phytoplankton could become even bluer. But in some waters, such as those of the Arctic, a warming will make conditions more suitable for phytoplankton, and these areas will turn greener. “Not only are the quantities of phytoplankton in the ocean changing.” she said, “but the type of phytoplankton is changing.”

And why does that matter? Phytoplankton are the base of the food web. If certain kinds begin to disappear from the ocean, Dutkiewicz said, “it will change the type of fish that will be able to live on.” Those kinds of changes could affect the food chain.

Whatever color changes the ocean experiences in the coming future will probably be too gradual and unnoticeable, but they could mean significant changes. “It’ll be a while before we can statistically show that the changes are happening because of climate change,” Dutkiewicz said, “but the change in the color of the ocean will be one of the early warning signals that we really have changed our planet.”

If you think memory problems are the preserve of the elderly, forget it. Young people frequently struggle to remember things too. A British study shows that the memory lapses (记忆差错) were as common among those in their twenties as in the 50-somethings.

Dr. MeWhirter, a neuropsychiatrist at the University of Edinburgh, questioned 124 healthy adults aged between 18 and 59 on how good they thought their memory was and how often they experienced memory lapses. Only 13 percent rated their memory as excellent. Half of respondents said they forgot why they had entered a room at least once a week and 40 per cent misplaced their mobile phone at least weekly. Some 48 per cent forgot to buy items on their shopping list at least once a week and 18 percent had had a mental blank over their PIN,

The researcher said we should not worry about memory lapses so much when we are older because we also have them when we are younger - in other words, memory problems are not always the first sign of dementia(痴呆).

Dr. MeWhirter said: "A lot of people will think that if you are starting to forget thing, it is something to worry about, but it is normal. It is just a function of how the brain works. You can only remember something if you properly attend to it. If you are doing lots of different things and not concentrating when you get in and just put your keys down somewhere, you may well forget where you have put them."

Dr. MeWhirter added that although someone in the early stages of dementia would have memory lapses, they would lend lo be unaware of them. In contrast, a healthy person would be able to remember that they had forgotten their keys last week. Other signs of concern include becoming lost, asking the same thing repeatedly and having difficulty with cooking and multitasking.