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Sunset on March 6 marked the start of the National Day of Unplugging, a 24-hour break from screens started in 2009 by the nonprofit Reboot. Encouraging people to unplug for 24 hours each week may look like an odd stance for Tiffany Shlain, who founded the Webbys, a prestigious award for Internet content. But she's not alone. Tech-free retreats have become common among Silicon Valley's elite. Even the famously tech-savvy Pope Francis said that “It's great to disconnect from cellphones.”
Ms. Shlain, whose book, “24/6: The Power of Unplugging One Day a Week,” was published last September, embraces this effort. Like many critics of tech overuse, she argues that always-available information feeds interfere with our fundamental need for mental downtime. “I just don't think we were designed to be on 24/7,” she says.
As technology becomes ever more entrenched in our lives, even some of its most passionate proponents are suggesting we step away from time to time. If we don't, they caution, we may be unwittingly making a huge sacrifice. “This really does touch everyone's lives,” says Kim Cavallo, an ambassador for the National Day of Unplugging and the founder of Lilspace, whose smartphone app rewards users for taking breaks from their phones with local perks and charitable donations. “We all feel the sense of disruption of human connection.”
Many critics agree that unplugging for just one day will not, by itself, change your relationship with technology. “I'm not a big advocate of extremes,” says Anastasia Dedyukhina, founder of the digital wellbeing training consultancy Consciously Digital. “It's much more interesting to find a balanced way.” Dr. Dedyukhina sees digital fasting as a first step in rescuing our lives from tech overuse, but warns that, like many simple fixes, it can miss the bigger picture. “It's actually very dangerous to see this as a solution,” she says, “because the problem is not that we are spending too much time on the screens. It's that so many of our functions are now outsourced to technology, and there's no culture around this-what's appropriate, what's not appropriate.”
Computer scientist Cal Newport agrees that unplugging can be a good first step, but warns that doing so needs to be seen not as a break-or worse, a “detox”—but as the first step in a transformation. “The reason to step away is not just to lose the habit of electronic products, but to give yourself back the space,” he says.
Dr. Dedyukhina, who used to be hooked on her phone, says changing her technology use has helped her recover some of her humanity. “In an age when computers are becoming more powerful,” she says, “we end up behaving more like computers.”
[A] To save electricity as much as possible in daily life.
[B] To stay away from the Internet and electronic products.
[C] To disconnect from things and people.
[D] To become a volunteer for the nonprofit Reboot.
[A] people can shut down their cellphones as they like
[B] some famous people do not like digital products
[C] it's not necessary to keep in touch with others all the time
[D] even tech fans consider it's good to unplug at times
[A] Supportive.
[B] Opposed.
[C] Neutral.
[D] Suspicious.
[A] be detrimental to our mental health
[B] strengthen the bonds between people
[C] have both advantages and disadvantages for human relations
[D] reduce communication between people
[A] It's time to make the decision to step away from electronics.
[B] Electronic products are doing much more harm than good.
[C] We should seek a balance between technology products and life.
[D] People should set aside space for themselves.
An article published in the journal Nature reports the identification of a new primitive bird. The fossil of the bird didn't look like much . But fragments of bone poked out of it, and it was from the last days of the dinosaurs, so it bore further scrutiny.
Birds are the only dinosaurs to have survived the mass extinction some 66 million years ago. But bird bones from that era are extremely rare, so paleontologists know little about how those creatures persevered. When CT scanning the rock, Daniel Field, a paleontologist at the University of Cambridge, didn't expect to find much. But when the X-ray image appeared on the screen, he recounts, there was “this incredible, complete bird skull staring straight out of the block at us.”
The fossil offers clues about why birds endured the asteroid impact that wiped out their fellow dinosaurs. And this tale of survival could illuminate modern lessons for resilience in the face of global catastrophe. “The most resilient things in the history of the world have been the plants and animals and other organisms that have survived mass extinctions, particularly the one at the end of the Cretaceous,” says Stephen Brusatte, a paleontologist at the University of Edinburgh. “So if you want to think about resilience, looking into the fossil record to see what survived is a great place to start.”
Paleontologists have some ideas about what might have made the surviving birds so resilient. Perhaps it had something to do with a diet enabled by their beaks, or where those enduring theropod dinosaurs nested. Or maybe it wasn't so much a single trait, but a mix of traits. The ability to eat a wide range of foods, minimal body size and caloric needs, and the freedom of flight likely all contributed to a flexibility that enabled them to shift with the ecosystems around them.
While the fossil's resemblance to living birds could suggest that shared features promote survival, there could be another explanation, says Julia Clarke, a paleontologist at the University of Texas at Austin. Traits don't always persist because they are beneficial, she explains. Sometimes they stick around simply because they aren't harmful enough for natural selection to weed them out.
The question about why birds-and crocodiles, and mammals-survived the end-Cretaceous mass extinction could bear on our world today, says Dr. Clarke. But to understand the relevance in today's rapidly changing climate, researchers have to figure out whether each group that survived did so for distinct reasons, or whether there is one cohesive pattern. What's needed are “more fossils from this point in Earth history,” Dr. Field says. “This isn't the end of the story.”
[A] The fossil of the bird did not look like any modern birds.
[B] The fossil of the bird appeared to be nothing special.
[C] The fossil of the bird was not worth studying.
[D] The fossil of the bird just looked like a few kinds of birds.
[A] scientists expect to find new breakthroughs at first sight of the fossil
[B] all kinds of dinosaurs have gone extinct about 66 million years ago
[C] complete bird bones are very precious because they are not easy to be found
[D] birds are also dinosaurs, though they don't look like conventional dinosaurs
[A] companion
[B] adaptation
[C] consideration
[D] identity
[A] Scientists need more fossils to confirm what makes birds survive.
[B] Scientists are sure that they will find more fossils from the Cretaceous.
[C] Scientists will not stop studying the newly discovered fossil.
[D] Scientists have figured out the main reason for the extinction of dinosaurs.
[A] Are Birds More Resilient than Dinosaurs?
[B] Why Dinosaurs Became Extinct Is Still a Mystery
[C] The Implications of Extinction of Dinosaurs
[D] Why Did Birds Outlive Other Dinosaurs?
Five years ago marked a peak for one of the predictable cycles of exaggeration for “self-driving” cars. At the time, virtually every major motor vehicle manufacturer and high-tech company predicted widespread deployment of automated driving systems (ADS) by 2022, which would supposedly lead to rapid obsolescence of conventional human driving.
With the benefit of hindsight, it has become obvious that the prevailing view during that period was false, with no more than a handful of advanced vehicles having been driven on public roads by last year without the need for onboard safety drivers to intervene when the automation systems needed human help. The term “self-driving” has lost its original intended meaning because the driving assistance feature on the cars that have been labeled “full self-driving” cannot work without constant human supervision.
By 2020, the CEOs of the major companies that had invested most heavily in ADS were starting to make public statements tempering their earlier optimism by pointing out that the rollout of automated driving would be incremental, beginning with operations under constrained conditions in tightly restricted locations. At the pace they are now going, it will require decades to expand to anything approaching nationwide deployment. Companies such as Tesla have not yet realized how far they are from their goal.
Consensus is growing among knowledgeable ADS developers about the technology and its near-term deployment. Foremost among them is the reality that the inherent complexity of the driving task makes it difficult for automated systems to accurately perceive the driving environment, anticipate the actions of other road users and recognize and respond to traffic hazards. Like children learning to control their own movements, ADS need to learn to crawl before they can walk and to walk before they can run.
Although the most popular projected use for automated driving a few years ago was automated ride-hailing passenger services, interest has shifted significantly toward the automated movement of goods. Ride-hailing services have the most favorable demand profile, short trip lengths and shared rides in dense urban areas. Those are the places that are the most technologically challenging environments for ADS. In contrast, long-haul trucking operations on interstate highways face simpler traffic and roadway infrastructure conditions. Freight vehicles have the additional advantage that they can be designed to drive extra cautiously to avoid conflicts with other road users.
Although some observers may perceive that “the bloom is off the rose” for automated driving in the current environment, the current situation actually marks a sign of progress. We should expect automated local small-package delivery in urban and suburban settings during the current decade. Automated urban and suburban ride-hailing services could become available on a limited basis as well.
[A] conventional human driving would still be popular worldwide
[B] all vehicles would be driven automatically
[C] automated driving would become mainstream
[D] self-driving cars would reach the peak of development
[A] automated driving has become extremely prevailing
[B] quite a few advanced cars can be driven fully automatically
[C] automated driving has been proved to be impossible
[D] fully automated driving is not yet a reality
[A] their past efforts are completely in vain
[B] the public is not interested in ADS
[C] self-driving cars are unprofitable
[D] it's a long way for them to reach their goal
[A] freight vehicles can run on interstate highways
[B] freight vehicles' driving environment is less challenging
[C] freight services won't have conflicts with customers
[D] freight services are in greater demand
[A] optimistic
[B] ambiguous
[C] skeptical
[D] critical
It was late summer at Lake Giles, a small glacial lake in northeast Pennsylvania, and Kevin Rose and his team were there to study the effects of acid rain. But in the process, they discovered something else-the lake was running low on dissolved oxygen. This is a condition researchers call “anoxia,” and it's a big problem. It can harm cold-water fish species and contribute to algae blooms that do even more damage to the lake. As Rose and his team rowed back to shore, they wondered whether their experience at Lake Giles was an abnormality. Rose and his team published a study earlier this month in Nature showing the widespread deoxygenation of lakes around the world.
Together, they compiled data on dissolved oxygen concentrations in more than 300 lakes and used academic, nonprofit, and public data, like statistics from the Environmental Protection Agency's online Water Quality Portal. “The real power is in a lot of government data sets,” Rose says.
In their analysis, the team found that although surface temperatures have been rising, deep lake waters have remained cool, but increasingly lost their oxygen due to a phenomenon called stratification (the division of something into different layers). If you have ever walked into a lake from the shore and found that the waters are substantially colder the further out you go, you have experienced it. Colder water is denser, so, like oil separating from water, it remains deep in the lake, while the surface water maintains its warmth.
But as lakes' surfaces have gotten warmer, the difference between the temperatures of their warm and cool parts has grown wider. So has the difference in their densities. That means more stratification. Once those two layers stop mixing well, oxygen from the surface is no longer being pulled into the deeper waters. Hotter temperatures also make the oxygen less soluble and less likely to be absorbed into the water.
Stratification is normally affected by season; it increases as the air warms. But climate change is hurrying that up. “That spring season has been moving earlier and earlier, which means stratification, that difference in density, is moving earlier and earlier too,” Rose says. Because it starts sooner, stratification lasts longer throughout the year, leaving the lake and its inhabitants with lower oxygen for prolonged periods of time.
While there's no way to directly add oxygen back to lakes, Rose points out, there are other ways to improve ecosystem health. Planting trees as buffer zones around lakes can prevent erosion and increase water clarity. It is also recommended that residents who live near bodies of water use fertilizer according to the instructions in order to prevent excess nitrogen and phosphorus from entering the lakes, unintentionally fertilizing algae blooms.
[A] the ecology of Lake Giles and other 300 lakes
[B] how the lakes like Lake Giles are changing
[C] the influence of acid rain on lakes around the world
[D] if other lakes have the same problem as Lake Giles
[A] The researches.
[B] The governments.
[C] The nonprofit groups.
[D] The academics.
[A] The area of the lake shrinks.
[B] There is less and less oxygen in the lake.
[C] The water of the lake become denser.
[D] The temperature difference between shallow water and deep water becomes smaller.
[A] Earlier spring.
[B] Later summer.
[C] Wetter autumn.
[D] Colder winter.
[A] Life in the lakes is in danger.
[B] The earth is getting warmer.
[C] Acid rain is doing more harm.
[D] Lakes are losing oxygen.