A new analysis shows that each U.S. nuclear plant reduced carbon emissions by an average 2 million metric tons in its first year alone. A handful of high-profile disasters have soured the public on nuclear power, but new reactors could change that. Researchers considered each plant opening and plant closure as an “event” to build an event study analysis.
Economists have analyzed two decades of data to find how well nuclear power replaces traditional fossil fuel power plants, especially as part of an overall goal of reducing carbon emissions. The series of event studies, published in the February issue of Resource and Energy Economics, considers data from the 1970s and ’80s and contextualizes them around the disaster at Three Mile Island in 1979. The researchers found that although the carbon emissions from fossil fuel plants are huge, the very small risk of very big disasters at nuclear plants has caused them to fall out of favor among investors.
The research team from Carnegie Mellon University, led by Edson Severnini, says its study is the first to synthesize data from the entire U.S.. The “event” in the event study was when a nuclear power plant opened in the ’70s and ’80s. The team looked at the electric grid before and in the year after a nuclear plant went online, comparing how much fossil fuel electricity was displaced by nuclear power in the local grid.
For each gigawatt hour (GWh) of nuclear power, the researchers found a corresponding 0.8 GWh reduction in fossil fuel power. Although the replacement isn’t a clean 1:1 ratio of nuclear for fossil, the effect is still dramatic. “Solely by displacing coal-fired electricity generation, the average nuclear plant opening results in nearly 2 million metric tons less CO2 emissions, 5,200 metric tons less SO2, and 2,200 metric tons less NOx within the first year,” the researchers write.
As a second project, the team looked at output data from forced closures between 1999 and 2014. (Anyone who grew up near a nuclear plant knows the spooky feeling when cooling towers on the horizon are offline.) The researchers found that fossil fuel power then re-replaced nuclear at the same average rate, and this was the same for the calendar month and the utility bill month.
So what’s the point here? Well, these researchers conclude that while public perception against nuclear power makes it unlikely that sundowned plants will be replaced, what will likely replace them is much dirtier fossil fuel power. Both the perception barrier and the regulatory cost of nuclear power is likely too high for nuclear to ever wage a comeback without pretty comprehensive reforms in place.
“Nuclear power generation has lower fuel prices in comparison to coal, but faces higher operations and maintenance costs that are likely driven by the increased regulatory scrutiny after the Three Mile Island reactor accident,” the researchers conclude. The public fear of nuclear, which has translated into a stifling of nuclear development since Three Mile Island more than 40 years ago, seems to pale in comparison to the medium-level constant risk posed by much higher emissions from fossil fuels.
What that means, the researchers say, is that it would take “a substantial amount of regulatory pressure on fossil fuels (in the form of an emissions tax, regional emissions standards, etc.)” to push the public imagination back toward cleaner nuclear power. If their analysis is correct, it will be interesting to see how cutting-edge modular reactors—which claim to be much safer and more containable in the event of an emergency—could reduce perceived risk and let cleaner nuclear power back into our hearts.
The scientists have warned that distinctive flavours of wines from Burgundy, Bordeaux and other historic regions can be lost forever due to climate changes.
A new study predicts that in order to cope with rising temperatures, producers will be forced to abandon species of grape they have relied on for centuries.
It means that the dry, delicate tones associated with the Pinot Noir used to make red Burgundies may have to be replaced by the more full-bodied Syrah, or spicy Grenache.
Meanwhile world-famous labels in the Bordeaux area, such as Chateau Latour or Chateau Margaux, could be forced to replace their rich and complex blends of Cabernet Sauvignon and Merlot with a more meaty Mourvedre.
The researchers at the University of British Columbia say that if the climate warms by two degrees – in line with current trends – more than 50 per cent of the world’s current wine-growing regions will be lost by the end of the century.
However, they believe the damage can be mitigated to around one quarter if producers replace their current grape varieties with species that perform better in the heat.
While public focused on a seafood market in Wuhan, China, as a novel virus source, a description of the first clinical cases published in The Lancet on Friday challenges that hypothesis.
The paper, written by a large group of Chinese researchers from several institutions, offers details about the first 41 hospitalized patients who had confirmed infections with what has been dubbed 2019-novel coronavirus (2019-nCoV). The earliest case became ill on 1 December and had no reported link to the seafood market, the authors report. “No epidemiological link was found between the first patient and later cases,” they state. Their data also show that in total, 13 of the 41 cases had no link to the marketplace either. “That’s a big number, 13, with no link,” says Daniel Lucey, an infectious disease specialist at the University of Georgetown
Earlier reports from Chinese health authorities and the World Health Organization said the first patient had onset of symptoms on 8 December—and those reports simply said “most” cases had links to the seafood market, which was closed on 1 January.
Lucey says if the new data are accurate, the first human infections must have occurred in November—if not earlier—because there is an incubation time between infection and symptoms surfacing. If so, the virus possibly spread silently between people in Wuhan and perhaps elsewhere before the cluster of cases from the city’s now infamous Huanan Seafood Wholesale Market was discovered in late December. “The virus came into that marketplace before it came out of that marketplace,” Lucey asserts.
The Lancet paper’s data also raises questions about the accuracy of the initial information China provided, says Lucey. At the beginning of the outbreak, the main official source of public information was notices from the Wuhan Municipal Health Commission. Its notices on 11 January started to refer to the 41 patients as the only confirmed cases and the count remained the same until 18 January. The notices did not state that the seafood market was the source, but repeatedly noted that there was no evidence of human-to-human transmission and that most cases linked to the market. Because the Wuhan Municipal Health Commission noted that diagnostic tests had confirmed these 41 cases by January 10 and officials presumably knew the case histories of each patient, “China must have realized the epidemic did not originate in that Wuhan Huanan seafood market,” Lucey tells ScienceInsider. (Lucey also spoke about his concerns in an interview published online yesterday by Science Speaks, a project of the Infectious Disease Society of America.)
Kristian Anderson, an evolutionary biologist at the Scripps Research Institute in San Diego who has analyzed sequences of 2019-nCoV to try to clarify its origin, says the 1 December timing of the first confirmed case was “an interesting tidbit” in The Lancet paper. “The scenario of somebody being infected outside the market and then later bringing it to the market is one of the three scenarios we have considered that is still consistent with the data, he says. “It’s entirely plausible given our current data and knowledge.” The other two scenarios are that the origin was a group of infected animals or a single animal that came into that marketplace.
Anderson on 25 January posted on a virology research website his analysis of 27 available genomes of 2019-nCoV. It suggests they had a “most recent common ancestor”—meaning a common source—as early as 1 October.
Bin Cao of Capital Medical University in Beijing, the corresponding author of the Lancet article and a pulmonary specialist, wrote Science in an e-mail that he and his co-authors “appreciate the criticism” from Lucey.. “Now It seems clear that [the] seafood market is not the only origin of the virus,” he wrote in an e-mail to ScienceInsider. “But to be honest, we still do not know where the virus came from now.”
Lucey notes that the discovery of the coronavirus that causes Middle East Respiratory Syndrome (MERS), a sometimes fatal disease that occurs sporadically, came from a patient in Saudi Arabia in June 2012 but later studies traced it back to an earlier hospital outbreak of unexplained pneumonia in Jordan in April of that year. Stored samples from two people who died in Jordan confirmed that they had been infected with the virus. Retrospective analyses of blood samples in China from people and animals—including vendors from other animal markets–may reveal a clear picture of where the 2019-nCoV originated, he suggests. “There might be a clear signal among the noise,” he says.
Scientists in Brazil concerned about the encroachment of religion on science and education policy, because of the appointment of a creationism advocate to lead the agency that oversees graduate study programs.
President Jair Bolsonaro’s administration on Saturday named Benedito Guimarães Aguiar Neto to head the agency, known as CAPES (Coordenação de Aperfeiçoamento de Pessoal de Nível Superior). Aguiar Neto, an electrical engineer by training, previously served as the rector of Mackenzie Presbyterian University (MPU), a private religious school here. It advocates the teaching and study of intelligent design (ID), an outgrowth of Biblical creationism which argues that life is too complex to have evolved by Darwinian evolution, and so required an intelligent designer.
Researchers are decrying the move. “It is completely illogical to place someone who has promoted actions contrary to scientific consensus in a position to manage programs that are essentially of scientific training,” said evolutionary biologist Antonio Carlos Marques of the University of Sao Paulo’s Institute of Biosciences.
The appointment creates “insecurity” about how CAPES will shape education programs, says Carlos Joly, a biodiversity researcher at the University of Campinas.
CAPES is a key federal agency within Brazil’s Ministry of Education. It is responsible for regulating, supervising and evaluating all graduate-level programs at Brazilian universities, and funds thousands of scholarships for masters and doctoral students. It also issues funding calls for research and provides training for teachers in primary and secondary education.
Aguiar Neto was recently quoted in an MPU press release as saying that ID should be introduced into Brazil’s basic education curricula as “a counterpoint to the theory of evolution,” and so that creationism could be supported by “scientific arguments.” He made the comments prior to the 2nd Congress on Intelligent Design, which was held at Mackenzie in October 2019. The event was organized by Discovery Mackenzie, a research center created by MPU in 2017 to mirror the Discovery Institute in Seattle, which also promotes ID.
Aguiar Neto had been rector at Mackenzie since 2011. At CAPES, he replaces Anderson Correia, who is now rector of the Technological Institute of Aeronautics (ITA), an elite engineering school connected to the Brazilian Air Force.
This is the second time under Bolsonaro that a nominee’s views on creationism have become an issue. In January 2019, Damares Alves, Bolsonaro’s newly appointed minister of women, family, and human rights, drew criticism for saying, in a 2013 video, that Brazil’s evangelical churches had lost influence in society by allowing scientists to “take control” of the teaching of evolution in schools. Brazil’s evangelical Christians are among Bolsonaro’s strongest supporters.
Is life possible on Mars? In recent days we’re back to hearing about plans for setting humans up on Mars. A few years ago this idea was in the spotlight because of now-defunct efforts like Mars One, which somehow got 200,000 people to express interest in what would have been a lifelong trip to the red planet. We’ve also seen Elon Musk’s vision of how SpaceX would eventually provide a human “backup plan” by permanently settling Mars.
This past week Musk brought the idea up again, in typically provocative fashion, by talking about sending 1 million people to Mars by 2050, using no less than three Starship launches per day (with a stash of 1,000 of these massive spacecraft on call). He also raised the possibility of giving wannabe martian settlers loans to enable them to pay for the opportunity. Naturally, for many observers this also provoked discussion of indentured servitude for those “seeking a new life in the off-world colonies”, to paraphrase a famous line from the 1982 movie Blade Runner.
But whatever you think about Musk’s pronouncements, or his businesses, there are some very serious scientific hurdles to setting humans up on Mars (and in full disclosure, I own a few Tesla shares and I greatly admire his vision and drive for terrestrial change as well as the space-launch business, but I’m also somewhat wary of people being taken seriously just because they have amassed a lot of cash).
One of those hurdles is radiation. For reasons unclear to me, this tends to get pushed aside compared to other questions to do with Mars’s atmosphere (akin to sitting 30km above Earth with no oxygen), temperatures, natural resources (water), nasty surface chemistry (perchlorates), and lower surface gravitational acceleration (1/3rd that on Earth).
But we actually have rather good data on the radiation situation on Mars (and in transit to Mars) from the Radiation Assessment Detector (RAD) that has been riding along with the Curiosity rover since its launch from Earth.
The bottom line is that the extremely thin atmosphere on Mars, and the absence of a strong global magnetic field, result in a complex and potent particle radiation environment. There are lower energy solar wind particles (like protons and helium nuclei) and much higher energy cosmic ray particles crashing into Mars all the time. The cosmic rays, for example, also generate substantial secondary radiation – crunching into martian regolith to a depth of several meters before hitting an atomic nucleus in the soil and producing gamma-rays and neutron radation.
An analysis by Hassler and colleagues, published in 2014 in Science, noted that a human expedition with 360 days total in interplanetary space, plus 500 days on Mars itself, would expose astronauts to just over 1 sievert of radiation. Now statistically that’s not too awful. It would increase the odds of you getting fatal cancer by some 5% over your lifetime.
However, if we consider just the dose on Mars, the rate of exposure averaged over one Earth year is just over 20 times that of the maximum allowed for a Department of Energy radiation worker in the US (based off of annual exposure).
And that’s for a one-off trip. Now imagine you’re a settler, perhaps in your 20s and you’re planning on living on Mars for at least (you’d hope) another 50 Earth years. Total lifetime exposure on Mars? Could be pushing 18 sieverts.
Now that’s kind of into uncharted territory. If you got 8 sieverts all at once, for example, you will die. But getting those 8 sieverts spread out over a couple of decades could be perfectly survivable, or not. The RAD measurements on Mars also coincided with a low level of solar particle activity, and vary quite a bit as the atmospheric pressure varies (which it does on an annual basis on Mars).
Of course you need not spend all your time above surface on Mars. But you’d need to put a few meters of regolith above you, or live in some deep caves and lava tubes to dodge the worst of the radiation. And then there are risks not to do with cancer that we’re only just beginning to learn about. Specifically, there is evidence that neurological function is particularly sensitive to radiation exposure, and there is the question of our essential microbiome and how it copes with long-term, persistent radiation damage. Finally, as Hassler et al. discuss, the “flavor” (for want of a better word) of the radiation environment on Mars is simply unlike that on Earth, not just measured by extremes but by its make up, comprising different components than on Earth’s surface.
To put all of this another way: in the worst case scenario (which may or may not be a realistic extrapolation) there’s a chance you’d end up dead or stupid on Mars. Or both.
There is also a real difference between a small group of astronauts being constantly monitored, advised, and trained to optimize their time on Mars (whether brief or long term), and a million settlers eager to be pioneers. The old trope of “what could possibly go wrong?” springs to mind.
Obviously no one, not even an emboldened SpaceX, is going to plop humans down on Mars en masse without worrying about all of this. But I think it’s an open question as to just how big a challenge the radiation hurdle turns out to be, along with all the other hurdles.
Thin touchscreen newspapers which flash up breaking news and can be rolled away, like in the films Minority Report and Harry Potter, are on the horizon after a breakthrough by scientists.
In the 2002 Steven Spielberg Movie, Tom Cruise is forced to make a speedy getaway when his face appears on the front page of a futuristic e-paper being read by a commuter.
Likewise moving newspapers have also featured in Harry Potter, but until now scientists did not think touchscreens would ever be small enough to make the idea a reality.
Now material scientists at Monash University in Melbourne have developed an ultra-thin and ultra-flexible electronic material that is 100 times thinner than existing touchscreens and can be rolled up.
When the leaves of one type of sweet potato are damaged they release a strong-smelling chemical warning that prompts other leaves to produce defensive proteins that make them hard to digest. New research tracks this odorous alert system.
“It’s sort of a shortcut,” says Axel Mithöfer, a plant ecologist at the Max Planck Institute for Chemical Ecology in Jena, Germany, and co-author of the study, which appeared last November in Scientific Reports. Other plants have chemical warning systems that prompt neighbors to prepare for attack, but individual leaves often wait to manufacture defensive compounds until bitten themselves. But this plant’s leaves produce the compound immediately when neighbors are bitten, he says.
To investigate this response, Mithöfer and his colleagues released caterpillars on the pest-resistant sweet potato strain Tainong (TN) 57 and its more susceptible cousin TN66, both native to Taiwan. Each “exhaled” at least 40 chemicals when attacked, but the TN57 leaves released twice the amount of a compound called DMNT, also found in other plant-defense responses.
Next, the scientists placed a healthy TN57 plant in a closed glass tank with one whose leaves had been pierced with tweezers. Within 24 hours high levels of a protein called sporamin formed in both plants’ uninjured leaves. Sporamin, also found in sweet potato tubers themselves, is what makes it difficult for humans to digest them uncooked—and it causes trouble in insect guts, too. When researchers released synthesized DMNT into a tank with healthy plants, the leaves again readily formed sporamin.
Mithöfer’s team is now probing the mechanism TN57 leaves use to “smell” and “recognize” DMNT. The researchers also hope to test whether other chemicals the leaves release also elicit defenses.
Cesar Rodriguez-Saona, an entomologist at Rutgers University, who was not involved in the study, says this research showcases an intriguing defense mechanism—although he cautions that DMNT exposure in closed tanks could be higher than what plants experience in open, windy fields. It is also possible, he notes, that unattacked TN57s may not always expend the energy to use this direct defense “shortcut.”
The departing wish of Egyptian priest Nesyamun 3,000 years ago was that he be allowed to speak in the afterlife, so that he could address the gods, and be granted entry into eternity.
Now, with the help of science, the holy man has indeed found his voice after death.
Academics at Royal Holloway, University of London, University of York and Leeds Museum scanned the mummy of Nesyamun, 3D printed his vocal tract then played soundwaves through it to create an impression of how the priest might have sounded.
So far, the only noise they’ve created is a nondescript bleat, sounding something like ‘beh’ but the researchers are hoping to use computer modelling to recreate words and even sentences.
Coronaviruses are common, and typically cause mild respiratory symptoms in people, such as a cough or runny nose. Some are more dangerous. SARS, which infected over 8000 people, was responsible for 774 deaths during an outbreak that began in 2003. MERS, which was first identified in 2012, is even more deadly – around 34 per cent of people infected with the virus die.
What are the symptoms of the new virus?
People who have been diagnosed with the virus tend to have a fever and cough, and some have difficulty breathing. The symptoms appear to set in between two days and two weeks after the person has been exposed to the virus, according to health authorities.
How is it diagnosed and treated?
Health authorities in China have sequenced the genome of the virus, and have shared this information, allowing groups around the world to be able to test for the virus. There are no specific antiviral treatments for the infection, so people with the virus are treated for their symptoms.
Where did the virus come from?
The World Health Organization told journalists this week that the agency is still working to pin down the source of the virus. But many of the first confirmed cases were in people who had visited a food market in Wuhan. The market, which sells live farmed and wild animals, has since been closed and disinfected.
A recent genetic analysis suggests that the virus resembles similar viruses that infect bats and snakes. Researchers believe that the virus may have resulted from separate viruses in bats and snakes recombining. This could have happened in the wild, but may also have occurred in the market, where the animals have been kept in close proximity to each other.
How did the virus spread to humans?
The same genetic analysis suggests that the virus may have developed the ability to jump from snakes to people thanks to a mutation in a gene for a protein. If the virus was secreted in the animals’ feces, this could have become aerosolised and breathed in, some researchers speculate.
Where has the virus spread to so far?
Most of the confirmed cases have been in Wuhan, where at least 444 people are known to have been diagnosed with the virus. But many more cases have been confirmed in China, including in Beijing, Shanghai and Guangdong. In total, there are over 600 confirmed cases in China alone.
But the virus has also spread internationally. Cases have been confirmed in Thailand, Japan, South Korea, the US, and most recently Singapore and Vietnam. So far, all the confirmed cases are people who have travelled from China. But hundreds of suspected cases are being investigated in countries across Asia, as well as the UK and Mexico.
How contagious is the virus?
It is too soon to know how easily the virus will spread. The virus is airborne, and we know it can be transmitted between people. Chinese authorities have presented evidence of fourth-generation cases in Wuhan, and second-generation infections outside of the city.
Yesterday, the World Health Organization heard preliminary calculations for the average number of infections that each infected person may go on to cause, known as R0. This is estimated to be 1.4 to 2.5 people per infected person. In comparison, seasonal flu usually has an R0 of around 1.3.
How deadly is it?
So far, 17 deaths have been linked to the virus, which suggests a low fatality rate of around 4 per cent. “Most people feel this is somewhere on a spectrum between a relatively mild infection and SARS, which had a very high case fatality rate,” says Mark Woolhouse at the University of Edinburgh, UK. Again, it is too soon to be sure. There are concerns that the virus could mutate and become more dangerous.
Scientists have discovered new molecule that can absorb the full spectrum of olar energy and turn it into valuable hydrogen. Freeing hydrogen to use as fuel is a major science holy grail in the 21st century. Costly, corrosion-resistant rhodium molecules can hopefully be swapped for something more economical.
The new form of self-contained micro-solar panel is made of rhodium, a wildly rare and precious metal coveted by car makers for its role in catalytic converters. Researchers assembled rhodium atoms into a scaffold structure, a term more often used in drug research. The way the molecules are bonded leaves room for sunlight to be “saved,” turning two photons from the sun into two electrons. Since the chemical reaction is direct, even slow or sparse photons from low-energy sunlight are captured.
Single-molecule catalysts aren’t new, but this research team says its system is 25 times more efficient, both because the molecule is just a better catalyst and because it absorbs the full spectrum of light. Hydrogen is extremely popular in alternative energy research, but catalyzing it economically and in large quantities has been a challenge. The more options researchers find and fine-tune, the better the odds of finding a feasible everyday way to make hydrogen.
Why does absorbing the full spectrum of light make such a difference? Well, existing solar panels absorb what looks like a lot of the spectrum: from violet light to red light, which is the whole amount visible to the human eye. But the same way we have to protect ourselves and our skin from ultraviolet light we can’t see, we have to remember to include ultraviolet as part of any discussion about harvesting solar energy. The same is true of infrared at the other end of the spectrum.
Visible light, from a human perspective, is less than half the sun’s total output. To keep up the analogy to UV rays, a solar panel that collects from less than half of the spectrum is like a sunscreen that doesn’t block UVB as well as UVA. It could be a lot better. And while this collecting molecule did well with low-energy light, which is one of the edge cases for solar collection, it could also do well with high-energy light—a way to absorb many more photons in a much shorter time.
Of course, a catalyst that requires the world’s most expensive precious metal doesn’t sound, at first blush, like a way toward sustainable hydrogen. But the researchers hope the structure of the catalytic molecule can translate to other materials. Part of the appeal of rhodium is that it resists oxidizing and corrosion, so the researchers could, for example, dilute it in an acid bath they could shine LEDs on to generate hydrogen.
If they can use other materials for the reaction itself, the team may also be able to extend the “lifespan” of the reaction, which they say is one of the big next steps toward turning an exciting research discovery into a potential application.