2 . We tend to think of large cities as melting pots — places where people from all sorts of backgrounds can mix and interact. But according to new research, people in big cities tend to primarily interact with other individuals in the same socioeconomic bracket (阶层), but people in small cities and rural areas are much more likely to have diverse interactions.

The researchers used GPS data collected in 2017 from 9.6 million cellphones across 382 metropolitan (大都市的) areas in the United States to determine how often people of different socioeconomic ranks crossed paths during the day — essentially how many times people had the opportunity to interact, even briefly, with someone in a different income bracket. They collected data on almost 1.6 billion path-crossings.

This large amount of extremely precise data allowed the researchers to see what has been missed by similar studies in the past. People living in the 10 most populous metropolitan areas, which include cities like New York City, Los Angeles, and Chicago, along with their surrounding areas, were significantly less likely to interact with people of different socioeconomic ranks than people in metropolitan areas with fewer than 100,000 residents.

The good news is that there are ways to build cities to promote more socioeconomic mixing. Looking at large cities, the researchers found that those that placed frequently-visited hubs (中心) in between different neighborhoods — instead of in the center of each neighborhood — were less separated.

“These big cities have managed to develop diverse interactions because the hubs that people visit the most — which turn out to be shopping centers, squares, and similar places — are between rich and poor neighborhoods,” said Hamed Nilforoshan, a doctoral researcher at Stanford University. “Those hubs act as bridges, allowing people to see each other and interact.”

The concept of “gap days”     1     (appear) on a variety of social media platforms recently. Unlike a gap year, a gap day means an     2     (extreme) brief period of relaxation and escape from everyday routine. After resting, people will continue to devote     3     (they) to the busy pace of normal life.

Apart from “gap days”, other similar expressions have made     4     hit on the Internet, such as “city walk”, “da zi (activity partner)” and so on. This growing trend of creating new phrases or euphemisms (委婉语) for something otherwise ordinary and common has caused     5     (heat) discussion.

Some people think that these kinds of new phrases better cater to (迎合) people’s mindsets,     6     (show) their optimism. For example, the common expression “taking a walk” is neutral (中性的). But “city walk”     7     (be) the positive version of it, meaning “to explore the city with a curious mind”.

Others disagree, however, and think that it’s simply just a kind of “sugaring up”, satisfying one’s need for showing off. For example, “city walk” is the same as “taking a walk”     8     general. But by calling it a “city walk”, people feel like they are doing something fancier than it actually is.

But no matter how we think of these phrases, they have taken root in our daily lives and have already gained wide     9     (recognize) among the younger generation. So     10     we need to do is not make them out to be bigger than they actually are.

4 . Today, many people are turning to social media for their fitness routines, with TikTok, one of the most popular platforms. Indeed, its fitness category has some 300 billion views. But are the posted works, exercises and challenges really safe and effective?

While fitness influencers can encourage people to become more physically active, which is a positive, the quality and accuracy of their content is a concern, according to a 2023 review in Frontiers in Public Health.

“There are a lot of unsustainable and unrealistic workouts on TikTok, and even some dangerous advice,” said Jess Brown, a certified personal trainer in Westchester, New York. “What’s more, much of the fitness information on TikTok isn’t backed by science or posted by fitness professionals. The workouts are usually generalized to anyone, too, and don’t take into account your health, your family history, your flexibility, your range of motion—the list goes on,” said Monica Jones, a certified personal trainer in Washington, DC.

One of the more popular TikTok fitness trends involves developing your abdominal muscles. These challenges often show an influencer doing one exercise or series of movements that, if repeated daily for a week or two, is promised to result in a sexy six-pack. “No way,” Brown said. “We’ve proven again and again that spot reduction isn’t a thing.”

“Unfortunately, there will always be trends centered around getting fast results, because those grab people’s attention. But it’s important to look at your fitness and health as a lifelong journey, not something you can achieve within 10 to 90 days,” Jones said.

How can you separate quality workouts from dangerous ones? First, check the information of the posters. They should be certified fitness professionals who have experience working with people. You also want a coach who emphasizes improving strength and health, not one who focuses on body type. A quality influencer should encourage mental well-being, self-care and the importance of listening to your body in addition to physical fitness.

5 . Marketers assume the more choice they offer, the more likely customers will be able to find just the right thing. For instance, offering fifty styles of jeans instead of two increases the chances that shoppers will find a pair they really like. Nevertheless, research now shows when there is too much choice, consumers are less likely to buy anything at all, and if they do buy, they are less satisfied with their selection.

It all began with jam. In 2000, psychologists Sheena Iyengar and Mark Lepper published a remarkable study. On one day, shoppers saw a display table with 24 varieties of jam. Those sampling the jam received a coupon for $1 off any jam. On another day, shoppers saw a similar table, but only six varieties of jam were on display. The large display attracted more interest than the small one. But when the time for purchase came, people seeing the large display were one-tenth as likely to buy as people seeing the small one.

Other studies have confirmed this result that more choice is not always better. As the variety of snacks, soft drinks and beers offered at convenience stores increases, for instance, sales volume and customer satisfaction decrease. These results challenge our opinions about human nature and the determinants of well-being.

Choice is good for us, but its relationship to satisfaction appears to be more complicated than we assumed. What’s more, psychologists and business academics have largely ignored another outcome of choice: More of it requires increased time and effort and can lead to anxiety, regret, excessively high expectations and self-blame if the choice doesn’t work out.

Without doubt, having more options enables us, most of the time, to achieve better objective outcomes. Again, having fifty styles of jeans rather than two increases the likelihood that customers will find a pair that fits. But the subjective outcome may be that shoppers will feel dissatisfied, which creates a significant challenge for retailers and marketers. Choice can no longer be used to justify a marketing strategy. More isn’t always better, either for the customer or for the retailer.

6 . You may hear the awful saying “You can’t teach an old dog new tricks”, which speaks to a common belief about older adulthood that it’s a time when we’ve become so set in our ways that we’re not likely to change.

Psychologists used to follow the same line of thinking: After young adulthood, people tend to become stabler as people age. However, more recent studies suggest that something unexpected happens to many people as they reach and pass their 60s: Their personality starts changing again. People’s personality can change in response to their circumstances, adapting to a changing life. These developments clarify personality is not a permanent state but an adaptive way of being.

We can’t say with certainty what factors are driving these shifts, but a few theories exist. One possibility is that personality is shaped by specific life events that tend to happen in older age: retirement, empty nesting or widowhood (丧偶). But such milestones aren’t very reliable sources of change. They affect some people deeply, but have no impact on others. Any one event could mean many different things, depending on its context. Jenny Wagner, a psychologist at the University of Hamburg, in Germany, gave an example. Losing a partner could be a great loss, but for some it could be a bit of a relief at the same time-say, for someone who’s been caring for their ill partner for years.

Granted, old-age personality changes don’t always result from a sense of helplessness or an endlessly shrinking life. Research has shown that when people get older, they commonly recalibrate their goals; though they might be doing less, they tend to prioritize what they find meaningful and really appreciate it. That may involve adjusting to what they can’t control, but it doesn’t necessarily mean they’re reacting to a bad life—just a different one.

At the same time, not all of the changes coming with old age are unavoidable. And if old adults had more support from their communities and society, perhaps they’d be better able to command their circumstances—rather than having to make up for factors slipping out of their grasp.

8 . Journal editors decide what gets published and what doesn’t, affecting the careers of other academics and influencing the direction that a field takes. You’d hope, then, that journals would do everything they can to establish a diverse editorial board, reflecting a variety of voices, experiences, and identities.

Unfortunately a new study in Nature Neuroscience makes for disheartening reading. The team finds that the majority of editors in top psychology and neuroscience journals are male and based in the United States: a situation that may be amplifying existing gender inequalities in the field and influencing the kind of research that gets published.

Men were found to account for 60% of the editors of psychology journals. There were significantly more male than female editors at each level of seniority, and men made up the majority of editors in over three quarters of the journals. Crucially, the proportion of female editors was significantly lower than the overall proportion of women psychology researchers.

The differences were even starker in the neuroscience journals: 70% of editors were male, and men held the majority of editorial positions in 88% of journals. In this case, the proportion of female editors was not significantly lower than the proportion of female researchers working in neuroscience—a finding that reveals enduring gender disparities in the field more broadly.

Based on their results, the team concludes that “the ideas, values and decision-making biases of men are overrepresented in the editorial positions of the most recognized academic journals in psychology and neuroscience.”

Gender inequality in science is often attributed to the fact that senior academics are more likely to be male, because historically science was male-dominated: it’s argued that as time goes on and more women rise to senior roles, the field will become more equal. Yet this study showed that even the junior roles in psychology journals tended to be held disproportionately by men, despite the fact that there are actually more female than male junior psychology faculty.

This implies that a lack of female academics is not the problem. Instead, there are structural reasons that women are disadvantaged in science. Women receive lower salaries and face greater childcare demands, for instance, which can result in fewer publications and grants—the kinds of things that journals look for when deciding who to appoint. Rather than simply blaming the inequality of editorial boards on tradition, we should be actively breaking down these existing barriers.

A lack of diversity among journal editors also likely contributes to psychology’s WEIRD problem. If journal editors are largely men from the United States, then they will probably place higher value on papers that are relevant to Western, male populations, whether consciously or not.

9 . Genetic testing companies have a long history of creative attempts to reach the mainstream. An early example was the sequencing of rock star Ozzy Osbourne’s genes in 2010, with accompanying guess about how they might have influenced his drug habits.

Lately, such projects have taken on a new, highly commercialized tendency. In 2017, we got the “Marmite (马麦酱) gene project,” run by London-based genetic testing start-up DNAfit. It claims to show that love or hate for Marmite was in our genes. The project turned into a full-blown marketing campaign, and even sold Marmite-branded DNA testing tools.

DNAfit is now working with Mercedes-Benz to find out whether specific genetic traits are associated with business wisdom. AncestryDNA, the world’s largest consumer genetic testing company, last year teamed up with Spotify to promote “music tailored to your DNA.” Just a few weeks ago, 23andMe, the second largest, announced a partnership with Airbnb to provide genetically tailored travel experiences, also inspired by ancestral DNA.

I have skin in this game. I run a genetic-testing start-up that connects people who want their genome sequenced with researchers who want data to improve their understanding of genetic disease. I believe that broadening access to DNA testing can be a powerful force for good, providing safer, more effective medicines and giving people more power over their healthcare. But these campaigns risk discrediting the industry, by giving a misleading impression of what genetics can and can't say and its role in determining behaviours and personal preferences.

Take the Marmite study. It covered 261 people — tiny, by the standards of the field. It was published not in a journal, but online on bioRxiv, a server where scientists typically put results before peer-review. Shortly after, researchers looked at the genetic data of more than 500 times as many people in the UK Biobank and found no such correlation. A large peer-reviewed study in 2013 found no significant link between genes and business common sense.

We need to inform the public about what this is all about: that is, the gathering of large amounts of genetic data. We need better regulation to ensure that consumers are clear that this may happen with this sensitive personal information. A checkbox on a 20-page web document full of legal terms should not be enough.

Scientists too, need to start asking hard questions about whether the information they are using has been sourced ethically. DNA testing has a great future, but we can't build this future with data acquired by any means.