“A room without books is like a body without a soul,” observed the Roman philosopher, Cicero. It can also be a sign of financial problems to come. New research has uncovered a strong connection between the earning of adults and whether they grew up surrounded by books as children.

    Three economists at the University of Padua—Giorgio Brunello, Guglielmo Weber and Christoph Weiss—studied 6000 men born in nine European countries and concluded that children with access to books could expect to earn more money than those who grew up with few or no books.

    They studied the period from 1920 to 1956, when school reforms saw the minimum school leaving age raised across Europe. They booked at whether, at the age of 10, a child lived in a house with fewer than 10 books, a shelf of books, a bookcase with up to 100 books, two bookcases, or more than two bookcases.

    Over the period studied, the research, published in The Economic Journal, found that an additional year of education increased a man's average lifetime earnings by 9%. Men brought up in houses with less than a shelf of books earned only 5% more as a result of the extra year's education, compared with 21% more for those who had access to a lot of books. And those who had access to books were more likely to move to the better-earning opportunities in cities than those without books. The men's first job was also much more likely to be a white-collar job.

    The economists offer a number of theories for the results. “Perhaps books matter because they encourage children to read more and reading can have positive effects on school performance,” they said.

    The number of books in children's homes can effectively predict their cognitive(认知的) test scores. This may indicate a home that encourages cognitive skills, which are important for economic success in life.

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    Barbara McClintock was one of the most important scientists of the twentieth century. She made important discoveries about genes and chromosomes (染色体).

    Barbara McClintock was born in 1902 in Hartford, Connecticut. Her family moved to the Brooklyn area of New York City in 1908. Barbara was an active child with interests in sports and music. She also developed an interest in science.

    She studied science at Cornell University in Ithaca, New York. Barbara was among a small number of undergraduate students to receive training in genetics in 1921. Years later, she noted that few college students wanted to study genetics.

    Barbara McClintock decided to study botany, the scientific study of plants, at Cornell University. She completed her undergraduate studies in 1923. McClintock decided to continue her education at Cornell. She completed a master's degree in 1925. Two years later, she finished all her requirements for a doctorate degree.

    McClintock stayed at Cornell after she completed her education. She taught students botany. The 1930s were not a good time to be a young scientist in the United States. The country was in the middle of the great economic Depression. Millions of Americans were unemployed. Male scientists were offered jobs. But female geneticists were not much in demand.

    An old friend from Cornell, Marcus Rhoades, invited McClintock to spend the summer of 1941 working at the Cold Spring Harbor Laboratory. It is a research center on Long Island, near New York City. McClintock started in a temporary job with the genetics department. A short time later, she accepted a permanent position with the laboratory. This gave her the freedom to continue her research without having to teach or repeatedly ask for financial aid.

    By the 1970s, her discoveries had had an effect on everything from genetic engineering to cancer research. McClintock won the Nobel Prize for Physiology or Medicine in 1983 for her discovery of the ability of genes to change positions on chromosomes. She was the first American woman to win an unshared Nobel Prize.

    What's fiercer than a lion? The honey badger (蜜獾), one of the toughest mammals in Africa and western Asia. Honey badgers stand less than a foot high. They are only a couple feet long. They weigh just over 20 pounds. Yet they have a reputation for toughness that is far greater than their size.

    So what makes the honey badger so tough? They have speed, but so do many animals. They aren't stronger than lions, so how do they stop them? The thing that sets the honey badge apart is their skin. Their skin is thick and tough. Arrows, spears, and bites from other animals can rarely go through it. Not only is their skin thick and tough, it is also loose. This allows them to twist and turn to fight back while another animal is attacking them.

    Honey badgers have long, sharp claws. These claws are good for attacking and even better for digging. Honey badgers are some of nature's most skilled diggers. They can dig a nine-foot tunnel into hard ground in about 10 minutes. They love to catch a meal by digging up the holes of frogs and snakes. They also use their digging skills to create their homes. They live in small holes in the ground and defend them fiercely.

    You don't get a reputation like the honey badger by running from danger. The honey badger is a fearless and tireless fighter. They will attack any creature that threatens them, man included. Because of the honey badger's reputation, most predators (食肉动物) avoid them. Some animals use the honey badger's reputation to their advantage. Adult cheetahs (猎豹) have spotted coats, but their kittens have silver manes (鬃毛) and look like honey badgers. Some scientists believe that their coloring tricks predators into avoiding them.

    You might be wondering: "If honey badgers are so tough, how did they get a name that makes them sound like a piece of candy?" The answer makes sense. Since honey badgers have such thick skin, bees rarely harm them. So honey badgers love to attack beehives(蜂窝). Honey badgers run after honey so aggressively that beekeepers in Africa have to use electric fencing to hold them back. There's nothing sweet about that.

    Against the supposition that forest fires in Alaska, Canada and Siberia warm the climate, scientists have discovered that cooling may occur in areas where burnt trees allow more snow to mirror more sunlight into space.

    This finding suggests that taking steps to prevent northern forest to limit the release of greenhouse gases may warm the climate in northern regions. Usually large fires destroyed forests in these areas over the past decade. Scientists predict that with climate warming, fires may occur more frequently over next several centuries as a result of a longer fire season. Sunlight taken in by the earth tends to cause warming, while heat mirrored back into space tends to cause cooling.

    This is the first study to analyze all aspects of how northern fires influence climate. Earlier studies by other scientists have suggested that fire in northern regions speed up climate warming because greenhouse gases from burning trees and plants are released into the atmosphere and thus trap heat.

    Scientists found that right after the fire, large amounts of greenhouse gases entered the atmosphere and caused warming. Ozone (臭氧) levels increased, and ash from the fire fell on far-off sea ice, darkening the surface and causing more radiation from the sun to be taken in. The following spring, however, the land within the area of the fire was brighter than before the fire, because fewer trees covered the ground. Snow on the ground mirrored more sunlight back into space, leading to cooling.

    "We need to find out all possible ways to reduce the growth of greenhouse gases in the atmosphere." Scientists tracked the change in amount of radiation entering and leaving the climate system as a result of the fire, and found a measurement closely related to the global air temperature. Typically, fire in northern regions occurs in the same area every 80 to 150 years. Scientists, however, found that when fire occurs more frequently, more radiation is lost from the earth and cooling results. Specifically, they determined when fire returns 20 years earlier than predicated, 0.5 watts per square meter of area burned are soaked up by the earth from greenhouse gases, but 0.9 watts per square meter will be sent back into space. The net effect is cooling. Watts are used to measure the rate at which energy is gained or lost from the earth.

On an autumn afternoon, a remote sheep farm in southern Greenland is quiet. The silence is abruptly broken when dozens of sheep come thundering across the hills overlooking the farm. Walking after them are Lars Nielsen and his 37-year-old son Kunuk Nielsen.

The Nielsen family has owned and run the farm since 1972. Kunuk says the summers now are longer than when he was a child and that drought has become a problem. The fields are not so green as those in the old days. He has to buy hay (草料) from European countries.

The effects of a warming climate are obvious on the land. While he intends to struggle on, his older brother Pilu has chosen a different path.

Pilu, 40, lives in Qaqortoq in the south of Greenland -- a town of about 3,000 people. Ten years ago, he got his helicopter pilot's license and is now part owner of a small company called Sermeq Helicopters. It caters to construction and telecommunication workers and an increasing number of foreign tourists.

Pilu says he loves his family's sheep farm. But he saw that warming temperatures were making remote areas of Greenland more accessible and wanted to look for other opportunities. His company's most popular tours include a visit to Greenland's glaciers.

The warming temperatures are also affecting traditional ways of life, particularly hunting. The sea ice is changing; it's becoming less so that hunting on ice becomes more difficult. When there's no sea ice, it's difficult to use dog sledges (雪橇), and the whole culture around having dogs and dog sledges and doing traditional hunting on the ice is sort of diminishing.

Besides, many Greenlanders, like Pilu, are leaving the countryside for towns and the capital city Nuuk, where opportunities are greater. A report found that Nuuk's share of Greenland's population grew from 17.2% in 1977 to 29.2% in 2014. If there were enough houses in Nuuk, the share would even be bigger.

The concept of a space elevator, while once confined to the realm of science fiction, is gaining traction as a potential reality within the next few decades. This belief is not unfounded, but rather stems from the ongoing advancements in aerospace engineering and materials science.

As an aerospace engineer and a physics professor, the allure of a space elevator—a colossal cable extending from Earth's surface into space, facilitating the transportation of both people and cargo—remains a compelling subject of study. In recent years, innovative approaches to design and engineering have surfaced, providing new insights into the feasibility and functionality of space elevators.

The rationale for constructing a space elevator is multifaceted. Firstly, it presents a significant opportunity for energy and cost efficiency, offering a more practical alternative to traditional rocket-based space travel. 

The economic and environmental benefits are substantial, as the space elevator would reduce the need for fuel-intensive rocket launches.

Secondly, the space elevator would revolutionize accessibility to space. The term "space mission" could evolve into "transit," reflecting the routine and weather-independent nature of space travel. This shift would not only make space travel safer for astronauts, mitigating the risks associated with rocket launches, but also open up the cosmos to a broader range of individuals and purposes.

Moreover, the space elevator acts as a gateway to the solar system. By releasing a payload at different points along the elevator, one could achieve orbit around Earth or the sun, depending on the release point, all without the need for propulsion.

While it may seem that I am an advocate for the space elevator, my true passion lies in the study of its mechanics and the potential it holds for our future. In a world facing numerous challenges, the pursuit of such ambitious projects allows us to dream of a time when humanity becomes responsible stewards of our planet, reaching for the stars while preserving our home.