A NASA-funded study used satellite to search for penguin poops (粪便) in Antarctica: funny at first sight though it resulted in unique insights on the Adelie penguin's diet and its future as the climate changes. The findings published recently unlocked the secrets about the species that can provide an early-warning of threats to Antarctica's delicate ecosystem.

Researchers from Stony Brook University used satellite images to see if the Adelie penguin's diet has been changing in response to Antarctica's changing climate. Adelie penguin population has dropped greatly in some areas even as the global population increases. The satellite images cannot show the penguins individually, but their presence can be detected by the stain (污渍) left on the ice by their waste, called guano.

Male and female penguins take turns incubating (孵化) in the nest. The guano builds up in the same areas occupied by the nests. Heather Lynch, associate professor at Stony Brook, along with his team, used the area of the colony as defined by the guano stain to work back to the number of pairs. A global survey for Adelie penguins turned up 3.8 million breeding pairs. Also, the satellite data can detect the color of the penguin guano, ranging from white to pink to dark red. White guano is from eating mostly fish; pink and red would be from eating mostly krill (磷虾). The team found that while the Adelie penguin's diet did show changes from year to year, no consistent pattern was obvious.

"This was a big surprise, since the abundance and distribution of Adelie penguins has changed dramatically over the last 40 years and scientists had assumed that a change in diet might have played a role," said Casey Young flesh, a graduate student from the university. However, continued changes in the physical environment and a growing krill fishery in the region are likely to have an influence on penguin prey (猎物) and penguin population itself. "Tools like this will be important for the management of the Antarctic ecosystem, which is often considered among the most primitive areas in the world," said Young flesh.

Why do some men settle down to form families with the mothers of their children, and others don't? Biology plays a role. Work published by Lee Gettler of the University of Notre Dame, in Indiana, clarifies how testosterone, the principal male hormone (荷尔蒙), operates.

Previous studies suggest that high levels of testosterone are bad for family life. Fathers with lower testosterone levels provide more child care while high-testosterone males are less likely to stick around. Dr. Gettler has shown something further. This is that a man's adult testosterone level seems correlated with whether his father was present during his teenage years.

His data come from a survey begun in the Philippines in 1983. This monitored the health and nutrition of 966 men enrolled as babies. It also collected extensive information on whether the fathers of these men were around and providing parental care in the households. It further documented whether participants got married, had children and whether they participated in child care. Crucially, it also measured their testosterone levels at the ages of 21, 26 and 30.

Overall, Dr. Gettler and his colleagues found that on becoming fathers, men had lower testosterone levels if their own fathers had been involved in their care during their teenage years. It has two possible explanations. One is that it is directly genetic (基因的). The other is that teenage experience actually modulates (调节) testosterone levels. This explanation, which Dr. Gettler favors, could lead to high-testosterone men abandoning their sons, who thus become high-testosterone in their turn.

He also found some of those in the survey whose fathers were absent during their adolescence, and who ended up with high levels of the hormone, did become caring fathers. Why this pattern should exist is an unanswered question. But a zoologist looking at these data might take it as an example of developmental plasticity (可塑性), in which the same genes produce different, but appropriate, outcomes in different circumstances.

Dr. Gettler's discovery throws a useful light on the problem of fatherless families, and how to try to end it.

    If maths is the language of the universe, bees may have just uttered their first words. New research suggests these busybodies of the insect world are capable of addition and subtraction (减法) — using colors in the place of plus and minus symbols.

    In the animal kingdom, the ability to count — or at least distinguish between differing quantities — isn't unusual: It has been seen in frogs, spiders, and even fish. But solving equations (方程式) using symbols is rare, so far only achieved by famously brainy animals such as chimpanzees and African grey parrots.

    Building on previous research that says the social insects can count to four and understand the concept of zero, researchers wanted to test the limits of what their tiny brains can do.

    Scientists trained 14 bees to link the colors blue and yellow to addition and subtraction, respectively. They placed the bees at the entrance of a Y-shaped maze (迷宫), where they were shown several shapes in either yellow or blue. If the shapes were blue, bees got a reward if they went to the end of the maze with one more blue shape (the other end had one less blue shape); if the shapes were yellow, they got a reward if they went to the end of the maze with one less yellow shape.

    The testing worked the same way: Bees that "subtracted" one shape when they saw yellow, or "added" one shape when they saw blue were considered to have aced the test. The bees got the right answer 63% to 72% of the time, depending on the type of equation and the direction of the right answer — much better than random guesses would allow—the researchers report today in Science Advances.

    Though the results came from just 14 bees, researchers say the advance is exciting. If a brain about 20,000 times smaller than ours can perform maths using symbols, it could pave the way to novel approaches in artificial intelligence (AI) and machine learning. Just don't ask the bees to do your homework anytime soon.

"There are more people actively learning a language through DuoLingo than in the entire US public school system." says Luis von Ahn, founder of the free language learning app. Since its launch (投放市场) in 2012, more than 30 million people have downloaded (下载) the app, which gamified education and attracted many language learners.

The growth of technology for educational use has changed the way in which people learn and receive education. This is particularly true for languages, an area in which the explosion of mobile apps and interactive software has provided choices to a range of people who were previously unable to receive foreign language education.

Von Ahn says that when he founded DuoLingo he decided to find a way for people to learn a language for free. Free use of languages was something he had a personal interest in addressing: he grew up in Guatemala, where he was surrounded by people all trying to learn English, half of whom were failing to do so and a lot of whom could not afford it.

One of the big changes caused by tech is the change in language learners. Languages have long been connected with the rich people, but now people from less rich backgrounds are finding affordable ways to learn.

Von Ahn says an unexpected result of DuoLingo being an app is that it's attracting an unlikely type of user. DuoLingo was designed (设计) to be like a game, and what the company has found is that many users aren't even necessarily diehard language fans, they're just looking for an educational way to kill some time.

"They're still procrastinating from something else, but at least it's somewhat useful." says Von Ahn, "The truth of the matter is that learning a language takes months or years. We have to find a way to keep them interested and that's where the gamification came in."

They  can be made  into turkey  sandwiches,  and turkey vegetable  soup, to name just  a few. This year I cooked two turkeys so I would have leftovers to make use of.

If you have cooked your turkey in the past and it was dry, I'm willing to bet you either overcooked it or didn't let it rest. You need a good thermometer.    Probe(探针) style is a personal preference. My Meater is Bluetooth enabled, and I can set it up on my iPad or iPhone; it will tell me how long I need and how long to rest.

Also, resting is so important when cooking meats. I have written about resting meat so many times. I will always lightly cover my turkey in foil and let it rest for 15 – 20 minutes at a very minimum. When you heat the molecules or cells, they begin to vibrate and move faster and faster.   Otherwise, all the moisture(水分) will leak. If you allow molecules to settle down and relax, the muscle tissue will keep that moisture, and when you cut into the bird, it will still be moist.

How hot you cook your turkey will also determine how moist it is. The temperatures I pull the turkey out of the oven at and when it is ready to cut are different. Proteins, will continue to cook even after you have removed them from the heat source, related to the molecules vibrating or moving rapidly.

After  you  finish  enjoying  your  feast,  the  delicately  cooked  turkey,  you  might  have a lot of leftovers.    It feels comforting, because you can not only enjoy the soup but you're using up the leftovers.

The human brain is the most complex and poorly understood biological structure known to man. Our human brain is relatively large for our body size and wrinkled in comparison to other animals' brains. Across species, brain size and wrinkle number is related to intelligence.

University of Copenhagen researchers have made an incredible discovery seeking to learn more about the  mammalian(哺乳动物的)  brain.  A  vital  enzyme,  a  special  material,  allows  brain  signals  to  be transmitted or transported. The enzyme is randomly turning on and off, even taking hours-long "breaks from work." These discoveries could have a significant impact on our understanding of the brain and the development of medicines. The discovery is featured on the cover of Nature.

Millions of neurons(神经元) are constantly communicating with one another, shaping thoughts and memories and allowing us to move our bodies at will. Neurotransmitters are transported from one neuron to another by a unique enzyme when two neurons meet to exchange a message.

This  process  is  necessary  for  neuronal  communication  as  well  as  the  survival  of all  complex organisms(extremely small living things). Until now, researchers all over the world assumed that these enzymes were constantly active, transmitting vital signals. However, this is not the case.

It is almost impossible to understand that the extremely critical process of loading neurotransmitters in containers is carried out by only one cell per container. Especially when we find that 40% of the time these cells are switched off.

Using a new method, researchers from the Department of Chemistry at the University of Copenhagen closely examined the enzyme and discovered that its activity switches on and off at random periods of time, contradicting our previous understanding.

"Contrary to popular belief, and unlike many other proteins, these enzymes could stop working for minutes to hours. Still, the brains of humans and other mammals are miraculously able to function," says Professor Dimitrios Stamou, who led the study from the research center at the University of Copenhagen's Department of Chemistry.

Vincent van Gogh was born on March 30, 1853, in a small village in southern Holland. As a child, he was serious and sensitive. He loved to draw, and his work showed talent, but no one encouraged him to become an artist. Instead, his father thought he should take a job—something like a carpenter. As a young adult, he wandered from job to job with little success and very little money, becoming more depressed with each failure. In March 1880, however, just before his 27th birthday, something changed inside van Gogh. He realized he was meant to be a painter, and he began to study art in Brussels, receiving money from his brother Theo, which helped him to live.

In 1886, van Gogh moved to Paris, hoping to learn more about color techniques being used by Impressionist artists there. Instead of grays and browns, his work began to use blue and red, and then yellow and orange. Soon he began to see life differently: Go slow. Stop thinking. Look around. You'll see something beautiful if you open yourself. These were the principles that guide his art. With his innovative (创新的) use of colors, van Gogh wanted to show his viewers how to better appreciate a flower, the night sky, or a person's face.

Today, people around the world immediately recognize Starry Nights and Sunflowers—both painted in bold, intense（浓重的） colors—as the work of Vincent van Gogh. Probably no other artist, at any time in any culture, has achieved such popularity. His Portrait （肖像画）of Dr. Gachet sold in 1990 reached more than $80 million, breaking the world record for art pieces. Many of his other works have also sold for millions. Of course, people are buying great art when they purchase his paintings. But they are also buying a piece of his story, which like his work, will live on forever.

In a paper published recently in Nature Communications, the authors, including experts from China's Tsinghua University, said that most of the current electricity demand in advanced, industrialized nations can be met by some combination of wind and solar power. "Wind and solar could meet more than 80 percent of demand in many places without crazy amounts of storage or additional generating ability, which is the critical point（临界点）, "said co-author Steve Davis, UCI professor of Earth system science, "if we want to have a zero-carbon emission（排放）future without using fossil energy resources".

The team analyzed 39 years' worth of hourly energy demand data from 42 major countries to evaluate the adequacy of wind and solar power resources to serve their needs. They found that a full shift to sustainable power resources can be easier for lower-latitude（低纬度的）countries, which can rely on solar power availability throughout the year. The researchers highlighted Germany as an example of a relatively smaller country, in terms of land mass, at higher latitude which will make it more challenging to meet its electricity needs with wind and solar resources.

"Historic data show that countries which are farther from the equator（赤道）can occasionally experience periods during which there is very limited solar and wind power availability, "said lead author Dan Tong, assistant professor of Earth system science at Tsinghua University. "One recent occurrence of this phenomenon in Germany lasted for two weeks, forcing Germans to turn to dispatchable（可调度的）generation, which in many cases is provided by fossil fuel-burning plants. Among the approaches the researchers suggested to alleviate this problem are building up generating capacity, developing long-term storage capabilities and pooling resources of multiple nations on a continental land mass to make the burden lighter to a certain country.

"Europe provides a good example to help people produce net-zero carbon electricity, "said Tong. "A lot of consistency and reliability could be provided by a system that includes solar resources from Spain, Italy and Greece with plentiful wind available in the Netherlands, Denmark and the Baltic region.

ChatGPT-a conversational language model which was launched in November and is free and simple to use - can swiftly produce poems, math equations or essays on topics, bringing concern that students will misuse the technology. And because it doesn't copy an existing text, there is no easy way to be certain whether a human or a bot wrote the answer.

As many educators began to worry about whether students may use ChatGPT to generate papers, Edward Tian had an idea. The 22-year-old student, who studies computer science and journalism, decided to build an app to detect whether a text- was human-written or AI-written.

Over a few days in a Toronto coffee shop during winter break, he got to work. On Jan. 2, he launched' GPTZero. It analyzes' different properties of a text for its "perplexity", which is the randomness of the text, and the "burstiness", 'which is the variation of the text over time. So, a human-written text would have high perplexity, something very unfamiliar to an Al model, and exhibit properties of burstiness, which are non-common items that appear in random clusters （集 群）, rather than being uniformly distributed.

Tian said he expected a few dozen people to ever try it. But he woke up the next morning stunned by the response. He has even heard from people all over the world— many of them are teachers or college admissions officers, Many people have subscribed for updates from Tian as he works to improve the technology.

The quick response to Tian's effort highlighted the breakneck pace at which technology is changing classrooms, teaching, and the ways that people define and understand learning. Tian believed everyone deserved to reap the benefits of Al, but safeguards were needed to make sure new technologies were not abused.

Tian said it would be sad if, years from now, people mostly relied on AI and writing became far more uniform. "There's something implicitly（含蓄地） beautiful in human prose, " he said, "that computers can never copy. "

The number of seabirds killed by colliding（撞击） with wind turbines could be cut by painting black-and-white stripes on the blades（叶片）, and poles, say researchers. Graham Martin at the University. of Birmingham, UK, and Alex Banks at Natural England, a public organization that has a say in planning applications for offshore wind farms in England, wanted to design a pattern that could be easily painted onto turbines to reduce their impact on bird life.

Between 140, 000 and 328, 000 birds are killed each year by onshore wind turbines in the US, according to, one estimate. It is harder to tell how many birds are killed by offshore turbines each year, says Martin, as they fall into the ocean,

A previous study, published in 2020, looked at the effect of painting a single blade black on four onshore turbines in Norway. Bird collisions were reduced by 70 percent compared with all-white turbines nearby. Martin believes that further improvements could have an even greater impact. Based on analysis of previous studies into bird vision and bird collisions with wind turbines, the two researchers came up with a series of guiding principles to aid their design of a turbine that would harm. fewer birds.

"Most birds do not see too much fine detail in their vision - especially compared to humans, " says Martin, so any design shouldn't be too complex. Many collisions occur in low light, so the design should be easy to decipher in the dark, while high internal contrast would help the turbine stand out against different backgrounds, such as a cloudy or sunny sky. In low levels of light, black-and-white patterns are best, says Martin. "In the dark, a red-and-white pattern would rapidly look like shades of grey, " he says. The design hasn't yet been tested, but Martin hopes that manufacturers will consider it, particularly as it would be easy and cheap to implement.