【推荐2】Stop those negative thoughts! When it comes to brain power, it appears your thoughts matter. That was the eye-opening conclusion of a study published in the journal Alzheimer’s and Dementia.

For this study, scientists carefully measured the cognitive(认知)function of 292 middle-aged to older people over a four-year period. The cognitive assessments included measures of memory, attention and language.

The study subjects(实验对象)had their thinking patterns regularly monitored by responding to a series of questions over two of the four years. The thought-pattem questionnaires were designed to identify repetitive negative thinking (RNT for short). RNT includes often thinking about negative past events as well as future sources of anxiety.

About a third of the study subjects had PET scans(正电子发射计算机断层扫描)of their brains tomeasure levels of the abnormal brain protcins, tau and amyloid. Tau and amyloid build up in people affected with Alzheimer’s disease.

The findings? Study subjects with greater RNT-these repetitive negative thought patterns-exhibited a clear decrease in cognitive function and memory over the four-year period. What’s more, they had more tau and amyloid built up in their brains. It is well-documented that our thoughts have powerful, direct effects on our bodies, so these results aren’t surprising.

Thankfully, studies show that we can change our thought patterns through mental-training practices, with meditation(冥想)documented to be one of the very best.

As someone who often got trapped in negative memories of the remote past, I can speak personally to the remarkable power of meditation to relieve this destructive thinking pattern, and I encourage everyone to explore this practice. I meditate every day and gratefully achieve that goal about 90% of the time.

Feel free to share this post with friends and loved ones because one of the greatest gifts we can give is the gift of better health. Enjoy!

【推荐3】Like a phoenix (凤凰), some stars may burst to life covered in “ash,” rising from the remains of stars that had previously passed on.

Two fireballs covered in carbon and oxygen, ashy byproducts of helium fusion (氦聚变), belong to a new class of stars, researchers report in the March Monthly Notices. Though these burning objects are not the first stars found covered in carbon and oxygen, they are the first discovered to have helium-burning cores.

“That merger (并合) tells you the star must have evolved differently,” says study author Nicole Reindl.

The stars may have formed from the merger of two white dwarfs (白矮星), the remaining hearts of stars that exhausted their fuel, Reindl further explains. One of the two was rich in helium, while the other contained lots of carbon and oxygen. These two white dwarfs had already been orbiting one another, but gradually drew together. Eventually the helium-rich white dwarf “ate” its partner, leaving carbon and oxygen all over its surface, just as a messy child might get food all over their face.

Such a merger would have produced a star covered in carbon and oxygen to burn nuclear fusion in its core again, says Tiara Battich, a German astrophysicist.

To test this idea, Battich copied the evolution, death and eventual merger of two stars on his computer and simulated (模拟) the process. He found that putting together a carbon-and-oxygen-rich white dwarf and a more massive helium one could explain the compositions of the two stars observed by Reindl and her colleagues.

“But this should happen very rarely,” Battich says. In most cases the opposite should occur, because carbon-oxygen white dwarfs are usually the more massive ones. For the rarer case to occur, two stars slightly more massive than the sun must have formed at just the right distance and the right time.

"The origins story Battich proposes demands a very specific and unusual set of circumstances, " says Simon Blouin, a Canadian astrophysicist. “But in the end, it makes sense.”

【推荐1】A strong sense of smell is a key component of a healthy and enjoyable life. Yet our sense of smell is in decline as a result of an unnoticed threat to our health: air pollution.

Scientists are finding that anosmia, a loss of the sense of smell, is becoming a widespread problem among people of all ages exposed to PM2. 5 pollutants constantly, which are tiny particles (微粒) that can enter our bodies with every breath we take.

The reason, they suggest, is that the olfactory bulbs (嗅球), which are located in our noses and packed with nerve endings, are affected by exposure to air pollution. The tiny particles cause illness either in the bulbs themselves or in the brain, impacting our sense of smell over time, “Our data show the risk of developing anosmia with constant particulate pollution is 1.6 to 1.7 times higher,” says Ramanathan, a doctor at the Johns Hopkins School of Medicine, America.

Ramanathan is an author of a recent study of nearly 2,700 patients, a fifth of whom had anosmia despite many of them being non- smokers.’ When he and his colleagues looked into the backgrounds of the affected patients, they found most of them lived in neighborhoods with significantly higher levels of air pollution.

The findings prove other studies with similar findings. One of these studies, conducted in a town in Italy, found that more than 200 teenagers and young adults between the ages of 15 and 25 suffered olfactory damage as a result of exposure to NO₂, a common component in traf-fic emissions. “This is alarming as olfactory loss affects patient safety, well-being, and it is a predictor of poor health,” says Ramanathan.

Yet the loss of a sense of smell is a condition that is often overlooked though it can bring about numerous health problems. A sense of smell is linked to memory as well and life is a lot less fun without it. “People don’t remember what the pastry that they ate in childhood looked like, but they remember what the shop smelled like,” says Ramanathan.

【推荐3】The world’s coral reefs are in bad shape. Climate change has led to coral whitening. Overfishing has disturbed the ecosystems that keep reefs healthy. Poisonous runoffs from human industry are destroying the “rainforests of the sea.” A new study has highlighted another threat to coral reefs：plastics.

Researchers analyzed corals from reefs in Southeast Asia and Australia. Almost everywhere they looked, they saw bits of plastic, including chip wrappers, Q-tips, garbage bags.

The team estimates that at least 11 billion plastic items are trapped in coral reefs in the Asia-Pacific and that number is increasing alarmingly. This could spell disaster for the world’s reefs. The likelihood of the corals developing a disease jumps from 4 to 89 percent when corals come into contact with plastics.

Further investigations are needed to determine precisely how and why plastics make coral open to different diseases. But it seems that plastic debris（碎片）slices open the skin of the corals, exposing them to bacteria.

“Plastic debris can cause damage to coral tissues by accelerating invasion of bacteria or by exhausting resources for immune system function during wound-healing processes,” the authors of the study write. Drew Harvell, co-author of the study, says that plastics also “shade the light coral needs and cut off water flow.”

It is vital to preserve the health of coral reefs for a number of reasons. Many marine creatures make their homes within the reefs. Reefs also protect coastlines from waves and tropical storms, support fishing industries and generate billions of dollars for the worldwide tourism industry every year.

Throughout the research, scientists noticed that the plastics problem was not evenly distributed. Reefs near Indonesia had the highest amount of plastic rubbish, while reefs near Australia had the lowest. This could be because Australia has the best waste removal system. It suggests that there is a relatively easy fix to the issue.

“We can clean up the problem,” Harvell told Fears. “It’s so much easier than climate change.”

【推荐2】China's space program took a major leap recently when it successfully landed the Zhurong rover(登防车) on Mars marking the country's first landing on another planet. Teams then rolled the rove onto the Martian ground and begin a mission to search for evidence of water and signs of past life.

The touchdown makes China the second county in history to land a rover on the surface of Mars. After months in orbit around the red planet, the Tianywen-l Spacecraft released the Zhurong rover for a landing in Utopia Planitia, a vast plain that may once have been covered by an ancient Martian ocean.

“Landing safely on Mars is a huge challenge, especially for China's first soft landing attempt," said Long Xiao, a scientist at the China University of Geosciences, "But it is a necessary step for Mars and deep-space exploration."

Mars is significantly harder to land on than the moon, says Michel Blanc at the Research Institute in Astrophysics and Planetology in France. But China has had a series of successful lunar missions that prepared it for a Mars landing.

China will openly share the data from Tianwen-1 and Zhurong the same way it has shared data from its lunar exploration missions, Long says, benefiting scientists around the world.

The mission will also set the stage for China’s next planned voyage to Mars---a sample---return attempt scheduled to launch around 2028.Beyond Mars, the country has plans to launch a Jupiter probe(探测仪), including a possible landing on the moon Callisto, to collect samples from a near-Earth asteroid(小行星), and to send a pair of spacecraft toward the edges of the solar system.

“In the age of ocean exploration, China has a history of Zheng He's voyages to Southeast Asia and Africa," says Zhang Xiaoping at the Macau University of Science and Technology, referring to early 15th-century explorations. Zhang views China's Mars mission as a continuation of these Ming Dynasty journeys.