【推荐2】A group of health experts released an early version of a new guidance recently. They say people at 60 years of age and older without heart disease should not take aspirin to prevent a heart attack, because the risk of damaging the body is greater than the protection from heart disease.

The group's guidelines are meant for people at higher risk of heart disease. This includes people with high blood pressure, high cholesterol (胆固醇), those who are highly overweight or who have conditions that increase their chances for a heart attack.

Anyone considering whether to start or stop the aspirin treatment should talk with a doctor first, the group advised. "Aspirin use can cause serious harms, and risk increases with age," said John Wong, a group member.

Doctors have long advised small amounts of aspirin every day for patients with a heart attack. The group's guidance does not change that. The new guidance was announced online to let the public comment on it until November 8. The group will study the comments and then make a final decision. Wong said the guidelines are being updated because of new studies and reexamination of older research. Aspirin is best known as a medicine to reduce pain. It also thins blood, which can reduce the chances for blood clots (凝块). But aspirin also has risks, even in small amounts. These include bleeding in the stomach or intestines (肠) and ulcers (溃疡). Both conditions can be dangerous.

Dr. Lauren Block, a researcher in New York, said the guidance is important because so many adults take aspirin although they have never had a heart attack. She recently stopped treating a 70-year-old patient with aspirin. Her patient, knowing about his heart attack risks, never has bad effects from aspirin, but he takes the new guidance seriously. 63-year-old Rita Seefeldt with high blood pressure took aspirin every day for about 10 years until her doctor told her to stop several days ago. "After all, science develops over time," she said.

【推荐3】Vitamin C for a cold? A good dose of Vitamin D on a sunny day? We all know that vitamins are critical for our health, but how did they get their names and when were they discovered in the first place?

American nutrition scientist Elmer McCullum conducted a variety of feed experiments with different animal populations and discovered that an “accessory” substance contained in some fats was essential to growth. That fat-soluble (脂溶的) substance became known as Vitamin “A” for “accessory.”

McCollum and others also conducted further experiments with rice-bran-derived nutrient, naming it Vitamin “B” after beriberi, which can cause heart failure and a loss of sensation in the legs and feet. Eventually, it turned out that the substance known as Vitamin B was a complex of eight water-soluble vitamins, which were each given individual names and numbered in order of discovery.

The custom of naming vitamins alphabetically in order of discovery continued. Today, four fat-soluble vitamins (A, D, E, and K) and nine water-soluble vitamins (Vitamin C and the eight B vitamins) are considered essential to human growth and health. Only one vitamin bucked the oh-so-logical naming system: Vitamin K, discovered by Danish researcher Carl Peter Henrik Dam in 1929. The substance should have been in line to be called Vitamin F given its discovery date. But Dam’s research revealed that the vitamin is essential for blood coagulation (凝固) — known as Koagulation in the German journal that published his research — and his abbreviation for the vitamin somehow stuck.

It’s been decades since the last essential vitamin — Vitamin B12 — was discovered in 1948. It now appears unlikely that scientists will ever discover a new essential vitamin. But even if there’s no Vitamin F or G in our future, that doesn’t mean nutritional discovery has stopped completely. If the golden age of vitamin discovery was an appetizer (开胃菜) of sorts, scientists are devoted to the main course — a rapidly evolving understanding of the ways food shapes our lives, one microscopic substance at a time.

【推荐1】Depending on what time of year they’re born, Monarch butterflies can live from 2 weeks to about 5 months. Most butterflies depend on their wings of the same shape to help in their flight. But there was a three-day-old Monarch with a badly damaged wing, suffering the injury during its development. His chance of survival would be slim. Luckily, Romy McCloskey was there to help.

“I have always had a love for butterflies. They have a very personal meaning to me. Before my mother died, almost 20 years ago, she said to me, ‘Romy, whenever you see a butterfly, know that I’m there with you, and that I love you.’ I fell into the habit of raising butterflies in my backyard.”

One day, by accident when she found one of her darlings got injured on a bush, Romy knew she had to help him. Romy turned her home into an operating room and used common household items to perform a wing transplant. Romy McCloskey is a professional fashion designer, so this was right up her alley. “Secure the butterfly and cut the damaged parts away. Don’t worry. It doesn’t hurt them. It’s like cutting hair or trimming fingernails. According to Romy, there’s no need to drug the butterflies when performing such a procedure. She compared their wings to human nails or hair, “They do not have pain receptors (受体).”

“After a day of rest and filling his belly with homemade nectar (花蜜), it is time to see if he will fly. With a quick lap around the backyard and a little rest on one of the bushes, and then off he flew! My heart soared with him, for sure! A successful surgery and outcome! Bye, little buddy! Good luck!”

【推荐2】A large supply of acorns (橡实) on the ground last winter provided food for chipmunks (花栗鼠) across New England in the northeastern US as spring returned. Acorns and other nuts are a main part of the animals’ diet. They also eat insects, berries, and other kinds of fruit. The substantial food supply kept chipmunks well fed as they got busy reproducing and having families this spring. Now, the growth in the chipmunk population is so noticeable, with people saying the animals are driving them nuts.

Shevenell Webb, a biologist with the Maine Department of Inland Fisheries and Wildlife (MDIFW), said： “While chipmunks are often entertaining, they can be a bother.” The animals dig through the ground, making holes and passageways. This can lead to the destruction of grass, flowers and other plant life. Chipmunks can be “cute” and “fun to watch in the forest” as they move in and out of holes like playful children, “When their mouths aren’t full of nuts, chipmunks make an interesting chip sound,” Webb said.

Steven Parren is a wildlife program official with the Vermont Fish & Wildlife Department. He said he couldn’t grow flowers with chipmunks digging them up. “They don’t even cease,” he said. There were so many acorns in one area that there was no way the animals could have put them all away for winter. In addition to chipmunks, he is also seeing more squirrels, rabbits and mice this year.

Experts note while small animal populations can sometimes explode, they usually return to normal. Chipmunks can be food for other creatures. They are easy targets for owls, snakes and foxes. But even if they survive such attacks, Webb said individual chipmunks usually only live about three years. Many New Englanders remember a similar rise in the area’s squirrel population in 2018. Webb said that increase led to a lot of roadkill. “We’ve never seen anything like that. That was a once — in — a — lifetime event.”

【推荐3】Most people have probably read a book or seen a movie or show about an AI (Artificial Intelligence) or robot that has become so smart that it can take over the world. The AI in stories like this is known as an AGI (Artificial General Intelligence). A true AGI would be intelligent in many different areas and would be able to learn on its own. Currently, there are no AGIs. Most experts believe it will be many years before an AGI could possibly be created.

Most current AI tools are good at just one task. But scientists have been working to improve AI models. The Al tool that’s gotten the most attention recently is ChatGPT, which allows users to “chat” with a powerful Large Language Model (LLM). When asked a question, ChatGPT answers quickly in perfect sentences. It makes up stories and games, writes essays, and much more.

ChatGPT appears to be extremely intelligent. But really, ChatGPT is simply guessing—based on its training information—which word is most likely to come next, over and over again. Last month, OpenAI announced a more powerful model—GPT-4. GPT-4 can create and explain jokes, and pass tests difficult for humans. GPT-4 has also been trained on pictures, and can be used in powerful ways. For example, it can create a working website from a description and a rough drawing of the site.

The rapid progress and more general skills of recent AI models worry some people. Last week, many computer experts published a letter calling for a six-month pause for any work on AI tools stronger than GPT-4 to make sure AI tools are safe.

However, some AI experts say the letter makes today’s AI tools sound more intelligent than they really are. Others say it’s more important to worry about real problems in current AI tools rather than imaginary ones in the future. Anyway, the letter has sent a strong warning that many people, including leaders, will be thinking about carefully.