American authorities arrested Masphal Kry, an official in Cambodia’s forestry administration, last November when he was heading to an international meeting about trade regulations for endangered species in Panama. Prosecutors accused him of conspiring with a smuggling ring. The contraband (违禁品): monkeys,     1     long-tailed macaques. His     2     allegedly grabbed wild macaques in Cambodia’s national parks and bribed officials to label them as captive-bred. Fake papers allowed Vanny Bio Research, a Cambodian pharma company, to ship these unfortunate primates (灵长类动物) to America for use in research. Mr Kry is facing trial in Florida’s Southern District Court. The federal government funds seven National Primate Research Centres (NPRCs), which     3     in total around 20,000 primates, not only macaques but also baboons and marmosets. These centres then     4     primates to labs across America. NPRCs have fulfilled only a third of requests for untested-on macaques in 2021 and prices have soared. Before the covid-19 pandemic a rhesus macaque cost $8,000; by 2022 they had     5     $24,000. Another species, long-tail macaques, is probably per pound currently the most expensive     6     wildlife, says Lisa Jones-Engel, a science adviser at PETA, an animal-rights group.

Getting lab monkeys from abroad became harder during the pandemic. Chinese authorities banned the export of all primates in early 2020. The Chinese government wanted to     7     the country’s wildlife trade, which is thought to encourage the     8     of pathogens—like sars-cov-2—from animals to humans.

That forced American companies to rely on less     9     South-East Asian suppliers. Many scientists believe poaching is prevalent across Cambodia. In February, the Department of Justice subpoenaed Charles River over 1,000 juvenile macaques the pharmaceutical company had bought from Cambodia; the DoJ suspected they were     10     in the wild then exported. These primates are now in Texas and Maryland but also in dilemma: they cannot be tested on, nor can they be flown back to Cambodia.

Throughout the world, only 15% of the material that are used to make clothing is properly recycled, according to the Alle SacUrthur Club, an organization in Liverpool, UK, that boosts the circular economy. Most clothing waste—an     1    (estimate) 82 million tonnes from the fashion industry alone-produced every year ends up buried or burnt.

    2    (handle) all that waste, methods to recover and reuse the material are intended as an active response to the future risks by researchers and start-up companies. Much of their focus is on chemical recycling,     3     the material is broken down into its building blocks and applied to create new materials, including fibres that     4     (weave) into new clothes. The challenges lie in     5     (develop) the processes for such treatment. They have to be practical, but they also have to be at least as cost-effective as simply making new fibres.

    6     the natural cellulose fibres from cotton, some other materials include human-made cellulosic fibres. They are derived from wood-pulp cellulose and may be used to produce materials such as viscose (rayon) and a similar material called lyocell.

A change in the manufacturing process is being applied to the textile-waste problem by Essen, a start-up in Seattle, Washington.     7     the company has fundamentally devoted to the process is that it uses discarded textiles, instead of wood, as the source of its cellulose. It has also adjusted the process to produce a fibre that the firm’s co-founder and president Christo Stan says is superior to     8     other cellulosics and cotton, and that can be recycled more times.

Although there are abundant technical challenges, the main barrier     9     widespread textile recycling could be economic, says materials engineer Lijiang Jiang at the Massachusetts Institute of Technology in Atlanta. “Most of the materials are not that invaluable,” Jiang says. So cheap it is to produce polyester, cotton and other fabrics     10     there’s little profit margin unless the recycling processes themselves are very inexpensive.

5 . In an ideal world, people would not perform experiments on animals. For the people, they are expensive. For the animals, they are stressful and often painful. That ideal world, ______, is still some way away. People need new drugs and vaccines. They want ______ from the toxicity（毒性） of chemicals. The search for basic scientific answers goes on. ______, the European Commission is moving ahead with proposals that will ______ the number of animal experiments carried out in the European Union, by requiring toxicity tests on every chemical ______ for use within the union’s borders in the past 25 years.

Already, the commission has ______ 140,000 chemicals that have not yet been tested. It wants 30,000 of these to be examined right away, and plans to spend between $4 billion — $8 billion doing so. The number of animals used for toxicity testing in Europe will thus, experts reckon, quintuple (翻五倍) from just over l million a year to about 5, unless they are saved by some dramatic ______ in non-animal testing technology. Animal experimentation will therefore be around for some time yet. But the search for substitutes continues.

A good place to start finding ______ for toxicity tests is the liver--the organ responsible for breaking toxic chemicals down into safer molecules that can then be eliminated from body. Two firms, one large and one small, told the meeting how they were using human liver cells removed incidentally during surgery to test various substances for long-term toxic effects.

PrimeCyte, the small firm, grows its cells in cultures（士音养基） over a few weeks and doses them regularly with the substance under ______. The characteristics of the cells are carefully ______, to look for changes in their microanatomy（组织学）. Pfizer, the big firm, also doses its cultures regularly, but rather than studying ______ cells in detail, it counts cell numbers. If the number of cells in a culture changes after a sample is added, that suggests the chemical ______ is bad for the liver.

Other tissues, too, can be tested ______ of animals. Epithelix, a small firm in Geneva, has developed an ______ version of the lining of the lungs. According to Huang Song, one of Epithelix’s researchers, the firm’s cultured cells have similar microanatomy to those found in natural lung linings, and ______ in the same way to various chemical messengers. Dr. Huang says that they could be used in long-term toxicity tests of airborne chemicals and could also help identify treatments for lung diseases.

All this suggests that though there is still some way to go before drugs, vaccines and other substances can be tested routinely on cells rather than live animals, useful progress is being made.

Satellites Can Help Us Fight Climate Change

At the beginning of 2021, President Joe Biden exclaimed that “science is back” as we continued our efforts to     1     the COVID emergency. That phrase continues to ring true across the federal government. Science and its applications are being used at every agency to deal with public health     2    , build new transportation infrastructure, inform policy decisions and tackle the climate crisis.

Recently the Interior Department’s U.S. Geological Survey assumed     3     of Landsat 9 from NASA, which built and launched it in 2021.This satellite is designed to     4     Earth’s land, water and other natural resources. Landsat missions support environmental sustainability and climate resilience. The Landsat program, which launched in July 1972, has helped us understand our planet and the changes that are occurring on it. That partnership has propelled research and observation forward through the launch of     5     Landsat satellites, each replacing its predecessors and working in tandem with new capabilities and strengths.

I attended the historic launch of Landsat 9 in California. It was nothing     6     of amazing. I toured the mission control center and met a young scientist from the Navajo Nation living far away from home. She uses Landsat     7     to see her home from many miles away, and with such data, she enables her community to manage water resources in the face of a changing climate. This is the power and beauty of science at work.

All around the globe, scientists are using Landsat and other imagery to interpret what is happening on Earth today and to compare it with the 50 years’     8     of data the Landsat program has collected.

This science-based program and those like it across federal agencies are powerful tools in our efforts to responsibly manage our resources. Their prioritization helps to demonstrate the Biden-Harris administration’s commitment to lead with science. So, too, the resources provided through the president’s Bipartisan Infrastructure Law and Inflation Reduction Act will be key to the development of longer-term sustainability measures as we     9     to climate change, including building more resilient communities and protecting our natural environment.

Landsat NEXT is the upcoming mission we will develop with NASA to power better science and decision-making for the next 50 years. Science is indeed     10     us on a path to a brighter future.

10 . As plastic waste increases rapidly around the world, an essential question remains unanswered: What harm, if any, does it cause to human health?

A few years ago, as microplastics began turning up in the organs of fish and shellfish, the concern was focused on the safety of seafood. Shellfish were a particular worry, because in their case, unlike fish, we eat the entire animal — stomach, microplastics and all. In 2017, Belgian scientists announced that seafood lovers could consume up to 11,000 plastic particles (粒子) a year by eating mussels (贻贝), a favorite dish in that country.

By then, however, scientists already understood that plastics continuously fragment small pieces in the environment, tearing over time into fibers even smaller than a strand of human hair — particles are so small that they easily fly in the air. A team at the U.K.’s University of Plymouth decided to compare the threat from eating polluted wild mussels in Scotland to that of breathing air in a typical home. Their conclusion: People will take in more plastic by breathing in or taking tiny, invisible plastic fibers floating in the air around them—fibers from their own clothes, carpets, and soft covering on furniture — than they will by eating the mussels.

So, it wasn’t much of a surprise when, in 2022, scientists from the Netherlands and the U.K, announced they had found tiny plastic particles in living humans, in two places where they hadn’t been seen before: deep inside the lungs of surgical patients, and in the blood of unknown donors. Neither of the two studies answered the question of possible harm. But together they signaled a shift in the focus of concern about plastics toward the cloud of dust particles in the air, some of them are so small that they can get into deep inside the body and even inside cells, in ways that larger microplastics can’t.

Dick Vethaak, a professor of ecotoxicology (生态毒理学), doesn’t consider the results alarming, exactly—“but, yes, we should be concerned. Plastics should not be in your blood.” “We live in a multi-particle world,” he adds, referring to the dust, pollen (花粉), and smog that humans also breathe in every day. “The trick is to figure out how much plastics contribute to that particle burden and what does that mean.”