Children who spend a lot of time on their smartphones and computer devices may be at high risk of developing dry eye disease, scientists have warned. Researchers from Chung Ang University Hospital in South Korea showed that increased video display terminal (VDT) use such as smartphones or computers in children was found to be associated with the occurrence of ocular surface symptoms. The rate of smartphone use was 61.3 percent in the urban group and 51 percent in the rural group, researchers said. Smartphone use in children was strongly associated with pediatric DED. However, outdoor activity appeared to be protective against pediatric DED, they said. Older students in urban areas had DED risk factors and a short duration of outdoor activity.
Millions of people, particularly those above 60, around the world suffer sleep deprivation. Insomnia haunts them like a thief in the night, depriving them of muchneeded restorative sleep. The causes of insomnia are many, and they increase in number and severity as people age. Yet the problem is often overlooked during routine checkups, which not only diminishes the quality of an older person's life but may also cause or aggravate physical and emotional disorders, including symptoms of cognitive loss.
Almost everyone experiences episodic insomnia, a night during which the body seems to have forgotten how to sleep a requisite number of hours, if at all. As distressing as that may seem at the time, it pales in comparison to the effects on people for whom insomnia. The difficulty of falling asleep or staying asleep or waking much too early is a nightly affair. A survey, done in 1995 by researchers at the National Institute on Ageing in the United States, polled more than 9,000 people aged 65 and older living in three communities. It revealed that 28 percent had problems falling asleep and 42 percent reported difficulty with both falling asleep and staying asleep.
The numbers affected are likely to be much larger now that millions spend their pre-sleep hours looking at electronic screens that can disrupt the body's biological rhythms. Insomnia, Dr Alon Y. Avidan says, is a symptom, not a diagnosis that can be a clue to an underlying and often treatable health problem and, when it persists, should be taken seriously. He is director of the sleep clinic at the David Geffen School of Medicine at the University of California, Los Angeles. So-called transient insomnia that lasts less than a month may result from a temporary problem at work or an acute illness; short-term insomnia lasting one to six months may stem from a personal financial crisis or loss of a loved one. Several months of insomnia are distressing enough but when insomnia becomes chronic, lasting six months or longer, it can wreak physical, emotional and social havoc.
In addition to excessive daytime sleepiness, which can be dangerous in and of itself, Dr Avidan reports that chronic insomnia "may result in disturbed intellect, impaired cognition, confusion, psycho-motor retardation or increased risk for injury". It is often accompanied by depression, either as a cause or result of persistent insomnia. A study of nursing home residents showed that untreated insomnia increases the risk of falls and frac- HEALTH Living Insomnia is a symptom, not a diagnosis and, when it persists, should be taken seriously Naheed Akhter tures. There are two types of insomnia. One, called primary insomnia, results from a problem that occurs only or mainly during sleep, like obstructive sleep apnoea, restless leg syndrome (which afflicts 15 to 20 percent of older adults), periodic limb movements or a tendency to act out one's dreams physically, which can be an early warning sign of Parkinson's disease. Unless noted by their bed partners, people with primary sleep disorders may not know why their sleep is disrupted. An accurate diagnosis often requires a professional sleep study: spending a night or two in a sleep lab hooked up to instruments that record respiration, heart rate, blood pressure, bodily movements and time spent in various stages of sleep.
The other, more common type of insomnia is secondary to an underlying medical or psychiatric problem; the side effect of medications, behavioral factors like ill-timed exposure to caffeine, alcohol or nicotine or daytime naps, or environmental disturbances like jet lag or excessive noise or light - especially the blue light from an electronic device - in the bedroom. Among the many medical conditions that can cause insomnia are heart failure, gastro-esophageal reflux, lung disease, arthritis, Alzheimer's disease and incontinence. Treating the underlying condition, if possible, often relieves the insomnia.
Regardless of the reason for insomnia, it can become a learned response when people anticipate having difficulty falling asleep or returning to sleep after middle-of-the-night awakenings. They may spend hours lying awake in bed worrying about being unable to sleep, and the anxiety itself impairs their ability to sleep. The more one frets about a sleep problem, the worse it can get. Nonmedical causes of insomnia are often successfully treated by practising "good sleep hygiene", a concept developed by the late Peter J. Hauri, a sleep specialist at the Mayo Clinic in the United States. That means limiting naps to fewer than 30 minutes a day, preferably early in the afternoon, avoiding stimulants and sedatives, avoiding heavy meals and minimizing liquid intake within two to three hours of bedtime, getting moderate exercise daily - preferably in the morning or early afternoon, maximizing exposure to bright light during the day, and minimizing it at night, creating comfortable sleep conditions, and going to bed only when you feel sleepy. If you still cannot fall asleep within about 20 minutes in bed, experts recommend leaving the bedroom and doing something relaxing, like reading a book (one printed on paper), and returning to bed when you feel sleepy. Many people resort to alcohol as a sleep aid. While it may help people fall asleep initially, it produces fragmented sleep and interferes with rapid eye movement (REM) sleep, Dr Avidan and others report.
For those who still need help with insomnia, cognitive behavioral therapy has proved most effective in clinical trials. Sleeping pills can be problematic, especially for older people who are more sensitive to their side effects, including daytime hangover. Alternatives include over-the- counter remedies like melatonin or valerian, which have more anecdotal evidence than research to attest to their efficacy. The brain makes melatonin, the body's natural sleepiness hormone, in response to darkness. There may also be some useful dietary aids, like bananas, cherries, kiwifruits, oatmeal, milk and camomile tea, though evidence for these is also primarily anecdotal.
Elevator rides are not usually worth documenting. But when you step into the elevator at Shanghai Tower, people often pull out their cameras. As the doors close, a screen at the elevator’s front lights up to show you the car’s location as it rises toward the building’s newly opened observation deck. A neatly dressed attendant informs passengers that the elevator has now reached a top speed of 18 meters per second, approximately 40 miles per hour.
It is, in fact, the fastest elevator in the world. At a ceremony in Tokyo in early December, the Shanghai Tower elevators and the company that made them, Mitsubishi Electric, were officially awarded the title by Guinness World Records. Yet many passengers may not even experience the top speed. To do so, you have to travel in a souped-up elevator car with a Mitsubishi technician who can flick a switch, making the speedometer on the screen turn red: 20.5 meters per second, or 45.8 miles per hour. China is experiencing an elevator boom. Over the past decade, the vast majority of elevators installed around the world have been placed in China, where rapid urbanization has met with a desire for ambitious “super-tall” skyscrapers. It has been estimated that by 2020, 40 percent of all elevators will be in China.
And when it comes to speed, the rest of the world cannot keep up. The Burj Khalifa in Dubai is the only skyscraper in the world taller than Shanghai Tower, but its elevators go barely half the speed. The fastest elevator in the West, installed at 1 World Trade Center in Manhattan, runs at a paltry 23 miles per hour. The Shanghai Tower’s elevator goes even faster than the Twilight Zone Tower of Terror, a Disney haunted-elevator amusement-park ride that hurls thrillseekers at 39 miles per hour. Look at a list of the world’s fastest elevators now, and five out of the top 10 are in China. But China’s vast elevator market is slowing. As it slows, elevator companies are becoming more cutthroat at every level. Companies such as Mitsubishi are in competition for huge contracts with companies from all over the world. Another Japanese elevator company, Hitachi, came close to winning the Shanghai Tower contract. It was awarded one in Guangzhou instead and then announced plans to beat Mitsubishi’s speed with its own TECHNOLOGY Living Sabrina Islam 44.7-miles-per-hour elevators.
In the end, Mitsubishi installed new hardware on one of the elevators in Shanghai Tower, snatching the record back from Hitachi shortly after it was lost. Mitsubishi representatives said that the demands of the client, a consortium with links to the Shanghai municipal government, had prompted the decision. The world’s first safety elevator was installed by the American company Otis in 1857 in a hotel in New York City. It traveled five floors at a speed of less than half a mile per hour. According to Lee Gray, an associate professor of architecture at the University of North Carolina at Charlotte, speeds improved as elevators moved from potentially explosive steam engines to more-efficient hydraulic systems and on to electric traction systems. Visiting Europeans were soon unnerved by the speed of the elevators across the Atlantic. For much of the 20th century, the fastest elevators were installed in American cities. Then the speed race moved to Asia. Why Japanese firms have dominated high-speed elevators is a matter of debate. Some have reasoned that it is because of the technology shared with high-speed “bullet” trains, which Hitachi and Toshiba also make. Others have suggested that it may be because Japanese consumers are notorious for insisting upon smooth elevator rides.
What is certain is that these elevators can cost fantastic amounts of money. They need to be tested in enormous, custom-built towers. They have to be pressurized to make their rapid ascent comfortable. According to Mitsubishi, 40 people worked exclusively on the Shanghai Tower elevators. Mitsubishi and Hitachi would not say how much their elevators cost, but Jim Fortune, an American elevator consultant, estimated each installation at up to USD3 million. Many in the elevator industry say that while the technology is impressive, faster speeds do not serve a real purpose. But high speeds may be valuable as marketing tools, turning elevators into unlikely tourist attractions. And in an industry with its ups and downs, publicity can be important. Over the past two decades, China has rapidly urbanized. To boost urban density, hundreds of thousands of elevators and escalators have been installed each year. There are now more than 4 million units in the country — more than four times the number in the United States. Just over a decade ago, there were barely 700,000. Analysts say China accounts for 60 to 80 percent of new installations globally each year. No one else compares. The second-largest elevator market, India, is less than one-tenth the size.