As I begin to tell my friends about the seven days you treated my wife, Laura, in what turned out to be the last days of her young life, they stop me at about the 15th name that I recall. The list includes the doctors, nurses, social workers, and even cleaning staff members who cared for her.

     “How do you remember any of their names?” they ask.

     “How could I not?” I respond.

    Every single one of you treated Laura with such professionalism and kindness and dignity as she lay unconscious. When she needed shots, you apologized that it was going to hurt a little, whether or not she could hear. When you listened to her heart and lungs through your stethoscopes(听诊器)and her gown (长衫)began to slip, you pulled it up to respectfully cover her. You spread a blanket when the room was just a little cold and you thought she'd sleep more comfortably that way.

    You cared so greatly for her parents, helping them climb into the room's awkward recliner(躺椅), fetching them fresh water almost by the hour, and answering every one of their medical questions with patience.

    Then there was how you treated me. How many times did you walk into the room to find me sobbing, my head down and resting on her hand, and quietly go about your task, as if willing yourselves invisible? How many times did you help me set up the recliner as close as possible to her bedside? How many times did you check on me to see whether I needed anything, from food to drink, from fresh clothes to a hot shower.

    Really, I have all of you to thank for it with my eternal gratitude and love.

    In recent decades, social isolation has been recognized as a major risk to our health and long life. It's twice as bad for you as being overweight and nearly as bad as smoking. The rising number of people who say they are affected, across a wide range of ages, is shocking. In reality, you can suffer the ill effects of loneliness even if you are not socially isolated.

Comedian Robin Williams made a striking observation in 2014: "I used to think the worst thing in life was to end up all alone. It's not. The worst thing in life is to end up with people who make you feel all alone." Tracking large groups over time indicates that perceived（感知的）social isolation carries its own risk for morbidity（发病率）and mortality.

    The perception of isolation—from others of being in the social aspect-is not only a cause of unhappiness, it also signals danger. Fish have evolved to swim to the middle of their group when predators（捕食者）approach, mice housed in social isolation show sleep disruptions and reduced slow-wave sleep and prairie voles（田鼠）isolated from their partners then placed in an open field explore their surroundings less and concentrate on avoiding predators.

    These behaviours reflect an increased emphasis on self-preservation in the social aspect. For instance, fish on the edge of a school are more likely to be attacked by predators because they are easier to isolate and prey upon. Such observations reflect a more general principle that perceived social isolation in social animals activates neural（神经系统的）, neuroendocrine（神经内分泌的）and behavioural responses that promote short-term self-preservation. However, these responses bring a cost for long-term health and well-being.

    The range of harmful neural and behavioural effects of perceived isolation documented in adults include increased anxiety, hostility and social withdrawal; fragmented sleep and daytime tiredness; increased vascular resistance and changed gene expression and immunity; decreased impulse control; increased negativity and depressive symptoms; and increased age-related cognitive decline.

    Sadly, to date, attempts to reduce loneliness have met with limited success. A series of randomized controlled trials showed that they had only a small effect. Among the four types of interventions（介入）examined, talking therapy that focused on inappropriate thought processes had the largest impact. Social skills training, social support and increased opportunities for social contact were much less effective.

    A Swiss airplane powered only by energy from the sun left from Abu Dhabi early on March 9. Its creators hope the plane will make the first around-the-world journey without any fuel. The plane is called Solar Impulse 2. It has one seat and is made from carbon fiber. The plane weighs only as much as a car but its wings are wider than a Boeing 747. The plane's wings stretch 72 meters across. Those wings include 17,000 solar units, or cells, which capture the sun's energy. The energy allows the plane to fly day and night.

    Two Swiss scientists built the plane. Bertrand Piccard is also an explorer who made the first non-stop flight around the world in a balloon. Andre Borschberg is an engineer and trained fighter pilot. The scientists say they are not trying to alter the airplane industry. Instead, they want to show that new energy sources and technologies can achieve what some say is impossible. “We want to show we can fly day and night in an aircraft without a drop of fuel.” Mr. Piccard said.

    Some parts of the trip will require the pilots to be in the tiny plane for five to six days and nights in a row. So it is good that the pilot's seat is also a toilet.

    The plane's route begins in the United Arab Emirates. The pilots also plan stops in Oman, India, and China. They will cross the Pacific Ocean, stop in the United States, and continue over southern Europe or North Africa. They plan to arrive back in the United Arab Emirates in late July or early August.

    Internet viewers can go to the Solar Impulse website to see the plane's location and listen to broadcasts from the pilots.

    Teachers' Day is, interestingly, not celebrated on the same day all over the world. In some countries it is marked by a holiday, in others it is a working day.

    International Teachers' Day is celebrated on October 5. Being held ever since 1994, it is in honor of teachers' organizations worldwide. Its aim is to encourage supports for teachers and to meet the needs of students.

    China   In 1939, Teachers' Day was set for August 27, Confucius' birthday. In1951, the celebration was stopped. However, it was founded again in 1985, and the day was changed to September 10.

    India   Teachers' Day is celebrated on September 5 in honour of Dr. Sarvepalli Radhakrishnan, the second president of India, whose birthday falls on that day.

    Russia   In Russia, Teachers' Day was celebrated on the first Sunday of October between 1965 and 1994. Since 1994, the day is observed on the October 5, just the same day as World Teachers Day.

    The US   In the US, Teachers' Day is non-official holiday. It is celebrated on the Tuesday of the first full week of May. A number of activities are organized in schools to honor teachers. The celebrations can continue for the whole week of May.

    Thailand   In Thailand, National Teachers' Day is celebrated every year on January 16. The first Teachers' Day was held in 1957. The day is a holiday in schools.

    The recession (衰退) of 2008-09 was remarkable in rich countries for its intensity, the following recovery for its weakness. The labour market has also broken the rules, as new research from the OECD, a think-tank of mainly rich countries, shows in its annual Employment Outlook.

    Young people always suffer in recessions. Employers stop hiring them; and they often get rid of new recruits because they are easier to dismiss. But in previous episodes, such as the recessions of the 1970s, 1980s and 1990s, older workers were also kicked off. This time is different. During the financial crisis in 2008, and since, they have done better than other age groups.

    The researchers focus on movements in "non-employment" as a share of the total population in three age groups between the final quarters of 2007 and 2012. This measure has the advantage of including not just unemployment, where people are looking for work, but also inactivity, where people are not seeking jobs. Whereas the average non-employment rate in the OECD has risen by four percentage points among young people and by one-and-a-half points among 25-to 54-year-olds, it has fallen by two points among the 55-64 age group.

    Why have older employees done so well? In some southern European countries they benefit from job protection not afforded to younger workers, but that did not really help them in past recessions. What has changed, says Stefano Scarpetta, head of the OECD's employment directorate, is that firms now bear the full costs of getting rid of older staff. In the past, early-retirement policies provided by governments (in the mistaken belief that these would help young people) made it cheaper to push grey-haired workers out of the door. These have largely stopped.

    Many will argue that older workers have done better at the expense of the young. That view is wrongheaded. First, it is a fallacy that a job gained for one person is a job lost for another; there is no fixed amount of work. And second, as the report shows, young and old people are by and large not substitutes in the workplace. They do different types of work in different types of occupation: younger people are keen on IT firms, for example, whereas older folk tend to be employed in more traditional industries. There are plenty of things that should be done to help the young jobless, but kicking older workers out of the workplace is not one of them.

In life, once on a path, we tend to follow it, for better or worse. What's sad is that even if it's the latter, we often accept it anyway because we are so used to the way things are that we don't even recognize that they could be different. This is a phenomenon psychologist call functional fixedness.

This classic experiment will give you an idea of how it works and a sense of whether you may have fallen into the same trap: People are given a box of tacks (大头钉) and some matches and asked to find a way to attach a candle to a wall so that it burns properly.

Typically, the subjects try tacking the candle to the wall or lighting it to fix it with melted wax. The psychologists had, of course, arranged it so that neither of these obvious approaches would work. The tacks are too short, and the paraffin (石蜡) doesn't stick to the wall. So how can you complete the task? The successful technique is to use the tack box as a candle-holder. You empty it, tack it to the wall. and stand the candle inside it. To think of that, you have to look beyond the box's usual role as a receptacle just for tacks and re-imagine it serving an entirely new purpose. That is difficult because we all suffer to one degree or another from functional fixedness.

The inability to think in new ways affects people in every corner of society. The political theorist Hannah Arendt coined the phrase" frozen thoughts" to describe deeply held ideas that we no longer question but should. In Arendt's eyes, the self- content reliance on such accepted "truths" also made people blind to ideas that didn't fit their worldview, even when there was plenty of evidence for them.

Frozen thinking has nothing to do with intelligence. She said," It can be found in highly intelligent people."