Loneliness is like a disease, and what's worse, it's contagious. It can spread from one person to another, according to the recent research that stresses the power of one person's emotions to affect even people he doesn't know.

    The new analysis, involving 4,793 people who were interviewed every two years between 2005 and 2015, showed that a friend of a lonely person was 52％ more likely to develop feelings of loneliness by the time of the next interview. A friend of that person was 25％ more likely, and a friend of a friend of a friend was 15％ more likely.

“Loneliness is not just the property of an individual. It can be transmitted across people—even people you don't have direct contact with,” said John T. Cacioppo, a psychologist of the University of Chicago who led the study published in the December issue of the Journal of Personality and Social Psychology.

    Loneliness has been linked to medical problems, including depression, sleep problems and generally poorer physical health. Identifying some of the causes could help reduce the emotion and improve health, experts said.

Although the study did not examine how loneliness spreads, Cacioppo said another research has provided clues. “Let's say for whatever reason you get lonely. You then interact with other people in a more negative fashion. That puts them in a negative mood and makes them more likely to interact with other people in a negative fashion and they minimize their social ties and become lonely,” Cacioppo said.

According to Cacioppo, loneliness spread more easily among women than men, perhaps because women were more likely to express emotions.

Lonely people become less and less trusting others. This makes it more and more difficult for them to make friends－and more likely that society will reject them. Therefore, it is important to recognize and deal with loneliness．Cacioppo emphasizes people who have been pushed to the edges of society should receive help to repair their social networks.

    Does Fame Drive You Crazy?

    Few of us make money by losing sleep. But three graduate students at Brown University in Providence built a company around sleep deprivation(睡眠不足).

    Jason Donahue, Ben Rubin and Eric Shashoua were working late nights in Brown's business and engineering schools. They began thinking about ways to sleep better. They discovered they weren't alone in burning the midnight oil. Around 20% of Americans get less than six hours of rest a night.

    The friends imagined a smart alarm clock that could track how much time people spend in the most restorative(有恢复作用的) stages of the sleep cycle: REM (rapid eye movement) and deep sleep. What would it cost to design such a thing? Five years of research, 20 employees, $14 million and a whole lot of doubting from investors and scientists.

    Their company, Zeo, based in Newton, Mass, launched its product in June, 2009. The Zeo device uses a headband with tiny sensors(传感器) that scan your brain for signs of four sleep states-REM, light, deep and waking sleep. The smart alarm clock displays a graph of your sleep pattern and wakes you as you're not in REM sleep. In the morning you can upload the data to the company's Web site, and so track your sleep over time. Most of the feedback(反馈) comes in the form of Zeo's ZQ score showing how well you've slept.

    “Zeo allows people to unlock this black box of sleep,” says Dave Dickinson, a health-care CEO.

    Whether any of this actually improves sleep is up to the consumer, who will also need to make lifestyle changes like cutting out alcohol before bedtime or caffeine after 3 P.M.

    For now the company is selling Zeo online only. Dickinson also plans to spread it to countries such as Australia, where sleep deprivation approaches US levels.

    In recent decades there has been a strong push in American education to prepare all high school students for college. As a result, fewer and fewer young people are pursuing careers as skilled tradesmen. But teens should be encouraged to consider learning a trade.
    The average cost of a bachelor's degree is $127,000 and 70 percent of students apply for some form of student loans to help cover this cost. On average, loan borrowers graduate with $37,172 in debt. The average trade school degree, on the other hand, costs only $33,000 – less than what many four-year degree holders will still owe after graduation.
    I have a friend who is a highly educated college professor. He makes a comfortable living, and of course he loves his work, but recently as we discussed his own children's future career plans, it was my friend who raised the idea of pursuing a trade school degree. He told me that every time he calls his plumber (水暖工), the plumber answers his phone from his yacht(游艇).
    Of course not every tradesman can earn a yacht-buying salary, but there are a number of skilled professionals that can earn six figures.
    It's widely believed that academics are more valuable than physical or skilled work. Fortunately, there has been an effort to change that message in recent years and to restore dignity to trade education and tradesmen. Still, that message is going to be reinforced in classrooms and at home so that all students will recognize the beauty and value of possessing a skill, of being able to make something with one's own hands, and of offering a service that makes other people's lives not only better, but in many cases, possible.

If you've ever seen a sparrow steal your dog food or a crow open a garbage bag, you get a sense of that some birds have learned to take advantage of new feeding opportunities—a clear sign of their intelligence. Scientists have long wondered why certain species of birds are more innovative than others, and whether these capacities stem from larger brains or from a greater number of neurons（神经元） in specific areas of the brain.

It turns out that it's a bit of both, according to a recent study by an international team that included members from McGill University published in Nature Ecology and Evolution.

The researchers used a new technique to estimate the number of neurons in a specific part of the brain called the pallium in 111 bird species. The pallium in birds is equal to the human cerebral cortex（大脑皮层）, which is involved in memory, learning, reasoning, and problem-solving, among other things. When these estimates about neuron numbers in the pallium were combined with information about over 4,000 feeding innovations, the team found that the species with the higher numbers of neurons in the pallium were also likely to be the most innovative.

"The amount of time chicks spend in the nest as their brains develop might also play acrucial role in the evolution of intelligence," says McGill University Emeritus Professor Louis Lefebvre who spent more than 20 years gathering examples of feeding innovations. "Larger species of crows and parrots, which are known for their intelligence, spend longer in the nest, which allows more time for the brain to grow and accumulate pallial neurons."

The results of the study help to deal with previously opposed views of the evolution and significance of brain size and show how a life-history perspective helps to understand the evolution of cognition.

Getting rid of old tyres (轮胎) has long been a problem. Most are thrown into landfills or piled up in storage. Energy recovery is another common method. This involves burning tyres to generate electricity or heat for industries, but that produces planet warming pollution; or we use them to

repair roads, but chemicals from them might pollute the ground.

Some firms, therefore, have begun exploring an alternative. One such firm is Wastefront, which owns a big tyre-recycling plant in north-east England. In a couple of years, it will be able to turn 8 million old tyres into new products, including a black liquid called TDO (轮胎衍生油).

The process works by deconstructing a tyre into steel, rubber, and carbon black. After tearing down the steel, the remaining material is exposed to high temperatures in the absence of air to make the rubber change into a mix of hydrocarbon gases, and then they're removed. What is left behind is pure carbon black. Once the removed gases cool down, a part of them liquefies(液化) into TDO. The remaining gases are to be burned to fuel the process. This creates a closed-cycle system that prevents emissions. 

The carbon black can be reused to make new tyres. That is of interest to tyre-makers because it helps efforts to become carbon neutral—achieving a balance between the amounts of carbon dioxide produced and the carbon dioxide removed from the atmosphere. Producing new carbon black requires burning heavy oil or coal, which lets off plenty of greenhouse gases.

The recovered TDO is well-suited for making diesel ( 柴油). While not completely carbon-neutral, it does produce an 80-90% reduction in emissions of carbon dioxide, compared with the conventional fuel. The future market for such cleaner fuels will remain large, even though electric vehicles are on the rise. Fossil-fueled vehicles will exist for decades, particularly the big burners of diesel—trucks, which are harder to electrify. The fuel is also needed by trains and ships. So, anything that helps clean up overall emissions is useful—especially if it also eases a mountainous waste problem.