【151-152】城市生活能帮助一些濒危动物吗？ & What Is 5G Wireless Technology?

SCIENCE & TECHNOLOGY

Can City Life Help Some Endangered Animals?

February 13, 2019

At sunset every day, loud sounds can be heard coming from the sky in a community just east of Los Angeles.

The noises are from parrots. The colorful birds have become part of everyday life there.

The parrots leave their waste everywhere, said Havolynn Rose Owaleon. But she and many other community members have gotten used to the birds.

Owaleon said, "They are not quiet at all, but you know, it’s something that you listen for. Because if I didn’t hear them on a daily basis, then I know something is really wrong.”

Flying immigrants

Red-crowned parrots are now part of the ecosystem in Southern California. Their ancestors came from Tamaulipas, Mexico, where the parrots are now endangered.

The birds were often killed in their native land. But in the United States, they were sold to people as pets. Some of the parrots escaped or were released by their owners.

They have since reproduced and grown in number in an area with large numbers of people.

"They are good at making a habitat for themselves in major cities, and this is what happened in Pasadena and East L.A. So, these are birds that live pretty much exclusively off of trees that are also not native to our area," said Ursula Heise. She teaches at the University of California Los Angeles (UCLA) Department of English and at the Institute of the Environment and Sustainability.

Since arriving in Southern California, the red-crowned parrots have become such permanent fixtures that they are on the California Bird Records Committee's list of birds in the state.

“They’ve been naturalized as California citizens,” said Heise.

Cold-blooded immigrants

Often seen sunning themselves near a body of water, red-eared slider turtles are also not native to the U.S. West Coast. They also immigrated to the area as household pets. Later, some were released or escaped into the wild.

The turtles are native to the central United States. But they have survived in many parts of the country and around the world.

"Because this species is so commonly exploited for food and the pet industry, it’s the one that gets released the most often," said UCLA’s Brad Shaffer. He heads the La Kretz Center for California Conservation Science.

Urban haven

The success of the red-eared slider turtles and red-crowned parrots in the Los Angeles area has scientists wondering whether a city can be a place to help endangered non-native animals.

Shaffer said, “At least it’s living in the wild. It’s making its own living. It’s having the lifestyle that turtles or that parrots should have, it’s just doing it in a different place."

Heise noted that work crews have put up major buildings and added different kinds of plants in neighborhoods across Southern California.

In many cases, this has led to a reduction of biodiversity; the native species had trouble living in the newly created habitat.

But the other side of that, Shaffer said, is that new kinds of habitats have been created, in which some creatures could thrive. These artificial habitats could become new homes for birds, insects or other creatures whose native homes are threatened.

Shaffer said any non-native species that is added would have to be carefully chosen to limit the risk of harm to the existing wildlife population in the city and other areas.

I’m Jonathan Evans

Elizabeth Lee reported this story for VOANews.com. George Grow adapted her report for Learning English. Ashley Thompson was the editor.

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Words in This Story

ecosystem – n. a community of organisms and its environment

pet – n. an animal kept for pleasure, not usefulness

habitat – n. an environment where a plant or animal normally lives

biodiversity – n. all forms of life in an area

minimize – v. to reduce

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SCIENCE & TECHNOLOGY

What Is 5G Wireless Technology?

February 13, 2019

A sign advertises 5G at the Qualcomm booth at CES International, Wednesday, Jan. 9, 2019, in Las Vegas. (AP Photo/John Locher)

There has been a lot of publicity recently surrounding 5G, the next generation of wireless technology for the world. But what is this technology and how might it change our lives?

What is 5G?

5G stands for fifth generation, meaning the next step in the progression of technology to replace the current 4G system. 4G was the replacement for 3G, which came after 2G, and so on.

These systems are wireless computer networks.

Earlier “G” systems were designed to improve mobile communication operations. Each new technology brought major improvements in speed and greatly increased network capacity.

The new 5G system promises more of the same. It is expected to permit more users to do more things -- at a faster rate. Higher internet speeds and larger network capacity should result in better performance for device users connected to 5G.

However, technology experts say there is a major way that 5G is different than the earlier systems. It will move well beyond mobile network technology to affect many more devices and industries than other “G” versions.

Ignacio Contreras, of Qualcomm Technologies, talks about the new Qualcomm 5G platform network at CES International Wednesday, Jan. 9, 2019, in Las Vegas. The Qualcomm 5G platform release is scheduled for later in 2019. (AP Photo/Ross D. Franklin)

When will it be available?

Before we can all use 5G, wireless companies and phone makers will have to complete and deploy a whole new system. New phones and communication equipment must be built.

American wireless companies have been preparing for the new system for some time. They have been creating new network equipment and buying broadcasting space to carry 5G signals. They have built new 5G antennas to serve American cities and towns. Wireless providers will invest at least $275 billion in 5G-related networks in the United States, the industry group CTIA reported.

The first U.S. launch of 5G is expected to happen sometime this year. Industry experts expect it will take a few more years to go nationwide. It will take even longer to reach rural areas.

China is expected to launch 5G sometime in 2020, while European nations are likely to build their systems more slowly over time.

In the United States, the first 5G-ready phones should be available in the first half of this year. The first 5G iPhone, however, is not expected until 2020.

4G phones will work on 5G networks, but not at 5G speeds.

Dave VanderWaal, Senior Vice President of Marketing, LG Electronics USA, speaks during 2019 International CES, Monday, Jan. 7, 2019, in Las Vegas. (Jack Dempsey/AP Images for LG Electronics)

What can 5G do?

Wireless industry groups say 5G will help fuel future “smart cities” by connecting sensor networks. Such networks will be able to control vehicle traffic and quickly identify streetlight outages.

5G is also expected to connect self-driving cars and support new technologies involving virtual reality. Higher 5G speeds could also permit doctors to commonly perform remote medical operations. Factories and businesses could use 5G technology to increase automation and improve the collection of information.

What are the security concerns?

More data -- and many more kinds of data -- will be traveling across 5G networks. Much of the data could contain private details about individuals, businesses or government organizations. The increased data flow would give internet attackers a lot more possibilities to steal and misuse data.

In addition, the wider use of a 5G wireless network means any breakdown of the system would have more widespread and severe results. Such difficulties could affect public safety as well as world economic activity.

Richard Yu, CEO of Huawei Consumer Business Group, speaks as he unveils the 5G modem Balong 5000 chipset in Beijing, Thursday, Jan. 24, 2019. (AP Photo/Andy Wong)

Government system failures could create national security risks. A failure during a doctor’s remotely guided operation could lead to the death of a patient. Or a network breakdown could cause self-driving vehicles to crash.

The 5G network has caused tensions between the United States and China. The U.S. government has urged American companies not to use Chinese technology in communications networks because of security concerns. It has also pressed other countries to ban Huawei, a Chinese telecom company, from building 5G networks.

U.S. officials have long suspected the Chinese government could use Huawei network equipment to help carry out spying activities.

Huawei has rejected such accusations.

I’m Bryan Lynn.

Bryan Lynn wrote this story for VOA Learning English, based on reports from the Associated Press, Reuters, Agence France-Press and online sources. Ashley Thompson was the editor.

Are you looking forward to using 5G on your phone and in other areas of your life? Write to us in the Comments section, and visit our Facebook page.

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Words in This Story

network – n. system permitting people to communicate and share information through the internet using a computer or mobile phone

capacity – n. the largest amount something can handle

antenna – n. piece of metal used for receiving television or radio signals

sensor – n. device that detects or senses heat, light, sound, etc.

virtual reality – n. computer images and sounds that make you feel an imagined situation is real

remote – adj. far away from where something is happening

automation – n. the controlling of something using machines and not people

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