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US states have long designated their own official flowers, birds and mammals, which are local symbols that fire up affection or pride. Now the Illinois legislature has taken things to the next (microscopic) level by adopting Penicillium rubens-a mold that produces penicillin-as the official state microbe.
Scottish microbiologist Alexander Fleming discovered in 1928 that a fungus called Penicillium notatum produced penicillin, which became the world's first widely effective antibiotic. But P. notatum could not generate large-scale quantities of the drug, which became especially crucial when World War II broke out. So scientists at the University of Oxford sought help from the US Department of Agriculture's Northern Regional Research Laboratory (since renamed the National Center for Agricultural Utilization Research, or NCAUR), in Peoria, Illinois. Andrew Moyer, a microbiologist there, took on the problem.
Moyer's fellow researcher Mary Hunt found a moldy cantaloupe at a Peoria market and brought it to the lab for analysis, says NCAUR biochemist Neil Price, who championed the state microbe designation. As was the case with many women conducting research in that era, Hunt's contribution to the discovery and study of that mold-which turned out to be Penicillium rubens-was diminished at the time. Moyer's 1944 publication on P. rubens mentions Hunt only in the paper's acknowledgments, and the press referred to her as “Moldy Mary.” P. rubens could better tolerate a new fermentation process that let it quickly produce hundreds of times more penicillin than previously studied strains, which let the Allies massively scale up antibiotic production. The same strain is still used to manufacture penicillin today, Price says. “To think-a moldy cantaloupe from a fruit market in Peoria revolutionized the medical field for millions of people,” says State Representative Stephanie Kifowit, who co-sponsored the Illinois House version of the P. rubens bill.
Price discussed his idea for making P. rubens the state microbe with State Senator David Koehler, who ultimately sponsored the Senate version of the bill. “I thought,‘We have a state bird,’” Price says. “‘Why not a state microbe?’” Illinois is only the third state to take this step, joining the ranks of Oregon (which similarly honors Saccharomyces cerevisiae, or brewers' yeast) and New Jersey (whose state microbe Streptomyces griseus also produces an antibiotic). Some efforts to designate official microbes have faltered: Wisconsin failed to pass legislation honoring Lactococcus lactis in 2010, and Hawaii was unable to choose between Flavobacterium akiainvivens and Aliivibrio fischeri in 2013.
But the Illinois effort attracted bipartisan support and sailed through both houses of the General Assembly, passing unanimously in May. The P. rubens discovery “is an important part of Illinois history,” Koehler says. “I am glad to know that it will be forever tied to the state as our official microbe.”
[A] are chosen by the local residents
[B] are a new means to inspire patriotism
[C] can be a typical animal of the state
[D] are always adorable and pleasing
[A] the effectiveness of penicillin discovered by him in a fungus
[B] the difference in medical standards between the UK and the US
[C] the demand for mass production of penicillin in WWII
[D] the difficulties caused by war in large-scale production of penicillin
[A] were ignored in the scientific research field despite their contributions
[B] were the ones who frequented the fruit and vegetable markets
[C] were more capable of making important discoveries than males
[D] were given the recognition they deserved in papers and media
[A] Aliivibrio fischeri.
[B] Saccharomyces cerevisiae.
[C] Lactococcus lactis.
[D] Flavobacterium akiainvivens.
[A] A Discovery Revolutionized the Medical Field
[B] The Bias Against Women Was Prevalent in History
[C] Bills Can Only Be Passed with Bipartisan Support
[D] Illinois Has Selected an Official State Microbe
Growing up in poverty can have long-term negative consequences for children. Now, a study offering unconditional cash to a group of mothers on low incomes in the US is beginning to discover the precise role of parental income in child development. It is the first randomised trial to look at whether a basic income might affect the way a child's brain develops in this critical period.
Studies of children born into families with low incomes have found they tend to have more behavioural problems and are behind their peers when they start school. However, it isn't clear whether low income directly leads to these outcomes, or whether they are a result of other factors associated with growing up in poverty.
To find out, the researchers approached women on low incomes who had just given birth. Around 1,000 women agreed to be part of the study and were randomly assigned to one of two groups. One group receives an unconditional cash gift of $330 per month, and the other group receives $20 per month. Both groups will receive the money for the first 40 months of their child's life.
The team has been following up the babies every year since 2018. At each yearly follow-up, children are assessed for measures like sleep quality, developmental milestones, overall health and emotional development. One unique aspect of the study is the use of mobile EEG headsets to monitor the infants' brain activity in their home environments.
According to one of the study authors, “To date, the dots are not connected in a careful scientific way.” Though it is still too early to draw full conclusions, some preliminary results are already of interest. For example, some of the parents have allowed the researchers to keep track of their transactions. Those in the high-cash group appear to be spending more on books for their children, and spending more time reading together, according to surveys. This is potentially good news because reading to infants is known to be good for cognitive development, vocabulary and promoting important bonds between adults and children. The researchers say it also seems like very little money was spent on what they call temptation goods like gambling, alcohol and tobacco.
“To my knowledge, a study like this has not been done before,” says Charles Nelson at Harvard Medical School. Eventually, the findings could help with policy interventions to assist children born into poverty, or even to find ways to buffer against the effects of poverty later in life.
[A] may experience more problems in their adulthood
[B] often complain about their low-income parents
[C] are more likely to have conflicts with their peers
[D] miss out an important period of brain development
[A] are equally subsidized in the trial
[B] have been under great financial pressure chronically
[C] can receive money as long as 40 months
[D] are financed according to the economic status
[A] no valuable data have been collected by using mobile EEG headsets
[B] the follow-ups ignore some key indicators in the survey
[C] the trial should be conducted more comprehensively
[D] it is premature to arrive at any definite conclusion
[A] parents are better educated
[B] parents can provide more intelligent stimuli
[C] parents are more strict with their children
[D] parents take advice on expenditure
[A] ambiguous
[B] supportive
[C] doubtful
[D] indifferent
Energy companies and nations must leave nine-tenths of Earth's coal and almost two thirds of its oil and gas in the ground if the world is to hold temperatures to below 1.5 ℃ of global warming, a target beyond which climate change's impacts are dangerously amplified, researchers have calculated. Their analysis of which fossil fuel reserves are effectively “unextractable” if we are to meet the Paris Agreement temperature pledge makes the situation look terrible for petrostates. Globally, oil and gas production must fall by 3 per cent a year to meet the target.
James Price at University College London (UCL) and his colleagues built on an influential 2015 study on how much of the world's coal, oil and gas reserves must go unused to stay under 2°C of warming, but this time looked at the 1.5°C goal. The researchers assumed a “carbon budget” that was about half the size of the earlier study's, allowing the world to emit just 580 billion tonnes of carbon dioxide from fossil fuels between 2018 and 2100. “A key output is we see near a doubling of unextractable oil reserves,” says study author Dan Welsby, also at UCL, meaning that much more must go unused to remain under 1.5°C instead of 2°C. For a 1.5°C future, 89 per cent of coal, 58 per cent of oil and 59 per cent of gas must stay in the ground by 2050.
However, the researchers say those figures are probably an underestimate. The first reason is that they only modelled scenarios with a 50 per cent chance of hitting 1.5°C. Secondly, the modelling is based on relatively high amounts of CO 2 being removed from the atmosphere-about 6 billion tonnes of CO 2 a year to meet the temperature target. But the technology to do this is still in its infancy.
The global figures mask regional differences. Canada and Venezuela both have to leave an above average amount of oil reserves unused while the Middle East is more similar to the global average. But because of the sheer size of its oil and gas reserves, “that translates into huge volumes left in the ground”, says Welsby.
Some oil companies, such as BP, have cut their future oil and gas plans as they attempt to transition to low-carbon energy. Earlier this year, a major report by the IEA suggested no new oil and gas wells should be drilled if the world is to cut emissions to net zero by 2050. However, many national oil and gas companies plan to grow production. “We need to reverse course. Where we are now is a long way away from where we need to be,” says Welsby.
[A] paints a gloomy picture for the future of the fossil fuel industry
[B] indicates that it is impossible to stay under 1.5°C of global warming
[C] shows that only petrostates would be affected by the 1.5°C goal
[D] illustrates that it is very hard to extract some underground oil
[A] its conclusion could not be verified since it was based on unsubstantiated data
[B] it yielded a startling result by lowering the temperature goal by just 0.5°C
[C] its outcome showed more underground oil reserves exist than thought
[D] the “carbon budget” used in a previous study didn't stand up to scrutiny
[A] the urgency to reduce carbon emissions drastically
[B] the powerful technology used to remove CO 2
[C] the slim chance of achieving the 1.5°C goal
[D] the underestimated figures obtained by the model
[A] varies in the oil reserves from region to region
[B] can have more oil extracted than Canada and Venezuela
[C] should keep an average amount of oil untapped
[D] should take more responsibility for global warming
[A] Keep the Fossil Fuels in the Ground
[B] An Impossible Goal for the Future
[C] Alarming Situation for Fossil Fuel Industry
[D] Efforts to Protect the Earth from Warming Up
For most birds, eyes are essential to life on the fly. They help birds make split-second aerobatic movements amid dense branches and pinpoint distant predators or prey. Yet when studying how birds might adapt to our quickly changing world, ornithologists have largely overlooked eye size in favor of traits such as wing length and beak shape. Now, though, a lost “treasure trove” of bird eyeball measurements offers a new view.
In 1982 University of Chicago graduate student Stanley Ritland, using pickled museum specimens, carefully measured the eyeballs of nearly 2,800 species-a third of all terrestrial birds. He never published his data, but Ian Ausprey, a graduate student at the University of Florida, has just given it a second look. Ausprey's analysis, published in the Proceedings of the Royal Society B , supports previous work in Peru showing that smaller-eyed birds adapt better to changing habitats.
“We're able to show strong correlations between eye size, the type of habitat the birds use, their foraging behavior, as well as where in the world they live,” Ausprey says. Ritland's measurements indicated an inverse relation between eye and range size. Birds with smaller eyes tended to be migratory, traveling across many habitats; larger-eyed species had tighter ranges, concentrated around the equator and often shrouded by dense forest shade. The study suggests that smaller-eyed birds can seamlessly handle varying light levels as they travel, whereas larger-eyed birds struggle with glare outside of their dim woodlands.
Ausprey had already seen this play out in Peru's mountainous cloud forests. In these biodiversity hotspots, he says, “eye size is strongly related to how birds respond to agricultural disturbance.” Larger-eyed birds tend to disappear from brightly lit agricultural and deforested landscapes; smaller-eyed birds adapt. The new study expands Ausprey's Peru observations to a wider variety of birds elsewhere, including parrots, woodpeckers and finches.
Allison Shultz, an ornithologist at the Natural History Museum of Los Angeles County, who was not involved in the research, praises it for highlighting the importance of birds' light exposure. Her own work has found a link between bird coloration and environmental light, and she says she looks forward to future research exploring how light pollution and deforestation might further shape bird eyes. “I'd be very curious if we're actually seeing eyes evolving to better match newer light environments,” Shultz adds.
Ausprey says the study underline the importance of conserving habitats across the light-availability spectrum, especially patches of dense rain forests, to protect birds with eyes of all sizes from habitat loss.
[A] complete swift flight
[B] localize distant predators or prey
[C] adapt to the changing environment
[D] all of the above
[A] He measured the eyeballs of about 2,800 living birds.
[B] He was rejected by the journal he contributed to.
[C] His measurements provided a new perspective for other related studies.
[D] His research failed to find any apparent and useful law.
[A] the type of habitat determines the eye size of birds
[B] the range of birds is related to the size of their eyes
[C] larger-eyed birds are more selective in their habitats
[D] larger-eyed birds can only live in dim environment
[A] birds with smaller eyes appear more frequently
[B] crops are more vulnerable to migratory birds
[C] birds' eyes can adapt to bright light
[D] birds from surrounding areas like to flock here
[A] its result lends support to her work
[B] it stresses the importance of light for birds
[C] it highlights the severity of light pollution
[D] it emphasizes the importance of protecting birds' habitats