Science

It is not often that chemists create a new kind of chemical bond, but they have just done it. A covalent bond that relies on a single electron has been made almost a century after it was first proposed.

Takuya Shimajiri at the University of Tokyo and his colleagues have been testing the limits of chemical bonds for years. Previously, they experimented with unusually long and flexible bonds, and now they have taken on an idea first proposed in 1931 by chemist Linus Pauling: a chemical bond formed by just one electron.

All known covalent bonds, where atoms connect by sharing electrons, contain two, four, six or eight electrons – but Pauling theorised a covalent bond could exist with a single electron shared between two atoms. To create this, the researchers used a chemical reaction to remove an electron from an existing two-electron covalent bond between two carbon atoms. They used a large hydrocarbon that has exceptionally long bonds between its carbon atoms, which means it would be energetically costly for an electron from elsewhere in the molecule to replace the one they removed.

Shimajiri says past experiments that attempted such electron subtraction left behind weak bonds which broke too quickly for a definitive chemical analysis. But his team’s molecule remained stable enough they could analyse it with X-rays and several kinds of light. Based on how this radiation bounced off or was absorbed, they determined it had a stable one-electron bond.

“It’s not often that you find a molecule with a new kind of bond,” says Henry Rzepa at Imperial College London. He says the molecule had a total of 278 electrons, so it was a real feat to both remove the correct one and prevent all the others from immediately replacing it. Rzepa says this is a “major discovery” that could lead chemists to create whole new families of molecules.

Chemists can now study how one-electron covalent bonds may change chemical reactions, says Shimajiri. But he and his colleagues have bigger questions, too.

“We aim to clarify what a covalent bond is – specifically, at what point does a bond qualify as covalent, and at what point does it not? Our goal is to explore a wide range of bonds that have yet to be discovered,” he says.

Compared with other types of batteries, proton exchange membrane fuel cells have the advantages of high discharge power and no pollution, which is also an important carrier for hydrogen energy conversion and utilization. Platinum intermetallic compounds play an important role as electrocatalysts in a series of energy and environmental technologies such as proton exchange membrane fuel cells.

However, the process for synthesis of platinum intermetallic compounds needs to be reorganized into ordered Pt–M metal bonds driven by high temperature (~600°C), which usually has great side effects on the structure of the catalyst, such as the uneven distribution of size, morphology, composition and structure, which further affects the performance of the catalyst and batteries.

In response to this challenge, Professor Changzheng Wu’s group at the University of Science and Technology of China introduced semimetal atoms, such as Ge, Sb, Te into the synthesis process of platinum-based intermetallic compounds. The research is published in the journal National Science Review.

The chemical bonds formed between semimetal elements and platinum atoms (Pt–Ge, Pt–Sb, Pt–Te) have both characteristics of metallic and covalent bonds, thus breaking the limitation of the synthesis temperature for platinum intermetallic compounds. It is also beneficial to the electrocatalytic reaction of proton exchange membrane fuel cells.

Due to the partial filling of p orbitals in the metallization elements, the d-p π feedback bond is formed between platinum and semimetal atoms as a strong covalent interaction. This force can be used as a driving force to promote the ordering arrangement in the high-temperature synthesis process of intermetallic compounds, thus breaking the temperature limit for the synthesis of platinum intermetallic compounds.

In addition, the characteristics of both metallic bonds and covalent bonds can further promote the electron transfer and orbital filling of platinum active sites in the fuel cells, so as to achieve the improvement of catalytic activity and anti-toxic ability.

The semimetal-platinum intermetallic compounds can be synthesized at only 300°C, and they show extremely high oxygen reduction activity under CO toxicity in fuel cell electrochemical tests (mass activity of 0.794 A mg⁻¹ at 0.9 V voltage, attenuation of 5.1% under CO toxicity), which is 11 times that of commercial Pt/C catalysts.

This study realizes bonding and orbital optimization in fuel cell catalyst synthesis and working conditions by introducing semimetals, and provides new insights for rational design of advanced electrocatalysts for fuel cells.

Climate change is among the more difficult but important topics to teach to young people. It involves complicated science and data, and it can be really depressing, given the bleak picture it paints of Earth’s future.

So how do educators get students more engaged in lessons about climate change? One way that works is to make the lessons into a game.

As a professor of educational psychology, I conducted an experiment that found that high schoolers are more interested and absorb more information about climate change when it’s presented as a game.

In the study, 248 high school students throughout the U.S. were randomly assigned to either read a text about climate science or to play a number estimation game—that is, a game in which they guessed 12 numerical facts about climate change. I found that the number estimation game improved high schoolers’ climate change understanding, interest in science and willingness to take actions to help solve climate change.

For instance, one question asked: “What is the change in percentage of the world’s ocean ice cover since the 1960s?”

After students submit an estimate, a window pops up showing the true value—a “40% decrease” in the ice cover question. Gold stars appear to indicate their accuracy, as does a short explanation of the true value. The answers also list actions that people can take to address the issue and links to the sources of the information.

I found that students who played the game had a better understanding than those who did not that there is a scientific consensus around human-caused climate change. Students who played the game also thought the activity was more interesting and reported less boredom. These boosts in positive emotions and motivation were linked to reduced sense of hopelessness about climate change and improved willingness to act on climate change.

Why it matters

Climate change is a tricky topic for secondary students to learn. Not only is the science conceptually difficult to comprehend, but it can be psychologically difficult for them to accept and address the looming threat of climate change.

Compounding this problem, a 2020 report suggests that 20 U.S. states do not address these challenges in their state science standards, as they were found to insufficiently address the scientific climate consensus: that climate change is real, severe, caused by humans, but that there is hope for change. Findings from my study provide some principles for addressing this curricular gap.

What other research is being done?

Researchers are actively trying to find approaches that promote accurate climate change education that helps students understand the causes and explores solutions for the challenges ahead.

One promising approach emphasized in this study, in my prior research and by other researchers, is to present a handful of surprising climate change numbers to students after they estimate them. However, there are several alternative approaches that are also effective. For example, some research found success by breaking down complicated ways to evaluate evidence, while other research engaged students taking photographs of their local environment to depict climate science and reflect on possible solutions.

What still isn’t known

One big remaining question is how to encourage teachers to implement effective climate change education in their classrooms. Evidence suggests that teachers sometimes feel pressured to teach to “both sides” of the continuum of climate change perspectives, despite one side having more supporting evidence. Such inconsistent messages can diminish needed urgency and confuse students in the process. I think it’s worthwhile to investigate the specific challenges and rewards that teachers encounter when implementing clear and consistent climate curriculum in their classrooms.

This article is republished from The Conversation under a Creative Commons license. Read the original article.

The first explorers known to have reached the North Pole spent weeks dragging their sleds across the rough pack ice. Now, people can travel most of the way there from the comfort of a cruise ship, their passage eased by the catastrophic melting of ice caused by climate change.

The Arctic is shedding ice at a rate of 12 per cent per decade and is set to be ice-free in the summer by the 2030s – regardless of how fast we cut emissions from now on. Meanwhile, in Antarctica, the vast Thwaites glacier is cracking under the pressure of global warming (see “Antarctica’s ‘doomsday’ glacier is heading for catastrophic collapse”), and Antarctic sea ice has been tracking at record lows in 2024 for the second year running.

We must cut emissions, and fast, but that alone won’t be enough to stop the runaway melt in the Arctic. To buy us time and to buttress this delicate habitat from a warming world, geoengineering is probably our only hope.

One solution comes from start-up Real Ice, which plans to use seawater to thicken the Arctic’s ice (see “Plan to refreeze Arctic sea ice shows promise in first tests”). It is controversial. Geoengineering of this sort, opponents argue, risks distracting humanity from the gargantuan task of cutting emissions.

Yet there are good reasons to push ahead. Alongside the spectacular wildlife and rich cultural heritage there, the polar regions do the world a huge favour. Their white caps reflect solar radiation back into space, helping to keep Earth’s climate cool. The loss of Arctic sea ice also triggers a whole host of other feedbacks that would amplify climate change and play havoc with weather systems around the world.

Of all our geoengineering options, refreezing the poles is perhaps the most benign. There are, of course, risks. Thorough impact assessments will be vital to minimise any harmful effects on wildlife, local communities or wider Earth systems. But without action, the ice will disappear, destabilising the global climate.

Cuts to greenhouse gas emissions should have started decades ago. The delay has left us with no time to be squeamish about geoengineering.

Wageningen researcher Qi Wang has developed a new variant of low-sugar ice cream that mimics the texture and melting properties of traditional ice cream. By replacing half of the sugar with broken-down proteins or the sweetener xylitol, she succeeded in creating a smooth ice cream without the graininess often associated with low-sugar versions. However, the flavor still needs refinement.

By reducing sugar in the ice cream, the cold treat becomes less unhealthy. Such low-sugar ice cream has been around for a while, but it does not appeal to everyone. It often has a grainy texture and melts either faster or slower than regular ice cream. “Our tongue is very sensitive and detects even the slightest differences,” says Ph.D. candidate Wang.

To tackle this issue, she developed a low-sugar ice cream that closely resembles the texture and melting behavior of regular ice cream. Wang successfully defended her thesis today with the Physics and Physical Chemistry of Foods group.

Antifreeze agent

Although a scoop of ice cream may look simple, at a microscopic level it is actually a complex food, consisting of fat droplets, ice crystals, air bubbles, and unfrozen syrup water. Sugar plays a key role in maintaining this structure, particularly the ice crystals. “Sugar acts as an antifreeze agent,” explains Wang.

Like salt on icy roads, sugar helps to prevent ice crystal formation, which improves the mouthfeel: the best ice creams contain small ice crystals. The larger they are, the grittier and less creamy the ice cream becomes.

Wang set out to find other substances that could function like sugar in this regard. “We selected molecules that we expected, based on their structure, to be able to do something similar,” explains her supervisor, Elke Scholten. This led them to the sweetener xylitol, the amino acid lysine, and a blend of peptides and amino acids.

In a professional ice cream maker, Wang mixed the ingredients for ice cream and replaced half of the sugar with one of these substances, along with a larger molecule to maintain viscosity, such as larger peptides or maltodextrin. The result: three new variants of low-sugar ice cream, flavored with vanilla and sweetener.

Salty taste

In the lab, Wang used special equipment to measure the properties of the new ice cream.

“We melted it on a fine mesh,” she explains. “By recording the droplets that fall through, we can calculate how quickly the ice cream melts.”

She also used a device that punctures the ice cream to assess its hardness. The results were comparable to regular ice cream. But, of course, taste is a crucial factor too. Thus, Wang prepared the ice cream in a special food-safe laboratory and invited ninety participants to evaluate it.

The participants agreed that the low-sugar ice cream had the same soft, creamy texture and melted in a similar fashion as regular ice cream. However, the low-sugar variants received a lower overall rating.

On a scale of zero to nine, the variant made with broken-down proteins, as well as the one with lysine, scored around 4.5, compared to 7.5 for the regular ice cream. This was largely due to an aftertaste caused by the proteins, which gave the ice cream a slightly salty or bitter taste, according to Wang.

The variant with xylitol performed slightly better, with a score of 6.5, though the test panel also detected some aftertaste here. Nevertheless, Wang believes this aftertaste need not be an issue per se.

“The ice cream we have made is very plain, with no special flavors or toppings. If we optimize it with flavors like caramel or coffee, they could potentially mask the taste of the proteins,” says Wang.

Wang’s commitment to her low-sugar ice cream is clear from her future plans. While she aims to gain more experience working in the food industry in the Netherlands, she has not given up on her ice cream dream.

“In ten years’ time, I hope to open my own ice cream parlor, selling low-sugar ice cream,” says the newly minted doctor.

Long ago, flowing wind and water shaped Mars’s malleable sand and sediment into dunes, ripples and other landscape patterns, called bedforms. Over billions of years, some of these landforms hardened into rock—scientists then call them paleo-bedforms. Frozen in time, change only comes in the form of the slow erosion by dusty winds, burial by ancient lava flows or the occasional meteorite impact.

A team of researchers led by Planetary Science Institute Senior Scientist Matthew Chojnacki mapped and characterized paleo-bedforms across the red planet to better understand their diversity and Mars’s ancient climate. The paper was published in the journal Geomorphology.

Since 2013 Chojnacki has worked on HiRISE, the High-Resolution Imaging Science Experiment on NASA’s Mars Reconnaissance Orbiter, or MRO.

“I pulled together a collection of HiRISE images that had these weird features that looked like bedforms, but they were cratered and covered in rocks. They looked decrepit and fossilized,” Chojnacki said. “We wanted to investigate further.”

Their research turned up paleo-bedforms across landscapes of varying age, latitude and geologic context, including craters, canyons and basins. They can be classified into groups called paleo-dunes and paleo-megaripples, which were shaped by wind; fluvial paleo-dunes, which were shaped by water; and dune cast pits, which were paleo-dunes so eroded that only a shallow depression is left behind.

Paleo-bedforms were found all around the planet, but most were concentrated in Valles Marineris and Athabasca Valles, near the equator; Noctis Labyrinthus, west of Valles Marineris; Arcadia Planitia on the northern lowlands; Hellas Planitia in the southern hemisphere, and the highland-lowland transition between Arabia Terra and Apollinaris Mons.

“The most compelling and unambiguous paleo-bedforms were the dunes,” Chojnacki said. “A lot of these paleo-dunes are dead ringers for the modern dunes, they just look more decrepit.”

The most widespread paleo-bedforms were paleo-megaripples, which look like large fields of parallel ridges. These smaller bedforms occur when wind blows over abundant coarse sand.

“Paleo-megaripples are also compelling, but slightly less so than the dunes, because there are other geologic processes that could have formed similar looking landforms,” Chojnacki said.

Based on what the team knew about modern megaripples, they proposed an evolutionary model for these features: The wind first shapes them, then eventually stops, allowing for the hardening and cementing of the sand into rock, leading to their preservation and eventually degradation.

The rarest and most heavily degraded paleo-bedforms were likely shaped by ancient water, called fluvial paleo-bedforms. The team only found these in what are thought to be the remnants of ancient megafloods.

Chojnacki said he was surprised they didn’t find more of these fluvial paleo-bedforms.

“Mars has an abundance of dry river channels where more fluvial bedforms may have formed, but it appears their small size and channel infilling were not conducive for their preservation.” he said.

The team estimates that most of the paleo-bedforms were cemented into the geological record about 2 billion years ago or more recently. Most bedforms were likely buried following their formation and transport, likely by volcanic activity like lava flows or ash fall, until erosion revealed them again, while others cemented into rock without ever being buried.

“In other cases, active sand dunes along the north polar cap are migrating over older paleo-dunes, leading to their erosion. Seasonal ice can also erode the dunes,” Chojnacki said. “The variety of these bedforms speaks to the diversity of dynamics and conditions operating in the solar system.”

Now that this survey has revealed a large sample of paleo-bedforms on Mars, the team hopes to identify modern dune fields which may be headed in a similar direction.

“While many bedforms on Mars are active and migrating today, other fields are static and show evidence for some sort of stabilization process that may eventually lead to lithification,” Chojnacki said. “Understanding this continuum will hopefully allow us to better understand the changing climatic conditions of the red planet.”

A new research report released by Western Sydney University and Save the Children has revealed more than 6 in 10 children with access to the internet interact with “unknown others” daily despite concerns about online grooming, highlighting children’s demands for better online protection.

The report, “Protecting Children from Online Grooming,” was written by the Young and Resilient Research Center at Western Sydney University.

The research team held in-depth consultations with about 600 children and young people aged 8 to 18 from Australia, Finland, the Philippines, Cambodia, Colombia, Kenya, and South Africa, who shared their views and experiences of facing inappropriate requests online for personal information or images.

Professor Amanda Third, Co-Director of the Young and Resilient Research Center, said keeping children safe from online grooming requires a whole-of-community approach, with governments, NGOs, technology platforms, teachers, parents, caregivers, and children themselves all having an important role to play.

“Children and young people are finding their own ways to tackle this issue and devise solutions, but they are also calling on us to help equip them and their caregivers with the skills and knowledge needed to be able to safely navigate these rapidly evolving digital environments,” said Professor Third.

“To most effectively address this issue, it is crucial that we listen to the views and experiences of children and young people and engage them as active partners in the research and policy design process.”

Since the COVID-19 pandemic, incidents of online grooming and child sexual and financial exploitation have reached an all-time high, with an 82% rise in online grooming crimes against children reported in that period. Online grooming practices have also transformed, with the fastest growing form of online grooming targeting young men for financial extortion.

The report revealed children were more inclined to connect with strangers—or “unknown others”—online as they matured and became more social, motivated by a desire for friendship, fun and play, followed by a wish to stay informed about trends and events, and to connect over shared interests.

The findings also showed that while children across all cultures and age groups were more suspicious of people they didn’t know online than people they knew in person, 66% of the study participants still interacted with unknown others daily online.

Children in high-income settings were twice as likely to use privacy settings to protect themselves from unwanted contacts, compared to children from some low-income settings, but the potential to derive financial benefits was an incentive for children in middle-income countries to connect with strangers online, potentially compromising their safety.

While children have come up with numerous ways to protect themselves, they are calling for widespread, accessible, and targeted online safety education for themselves and their caregivers. In the discussions, the children also made concrete suggestions about how technology platforms and governments can implement changes that will keep them safer online.

Children reported that it was very difficult to ascertain the intentions of strangers online. Children were also particularly worried about being asked for personal information or nude pictures, being drawn into inappropriate sexually-oriented exchanges, or exposure to criminal activities.

The report found that children want and need better online protection, with children primarily using intuition and background checks rather than seeking help from trusted adults to manage their online interactions with people they don’t know.

The data also showed that children distinguish people they know well both online and in person from those they only know online, with 86% approaching the latter with caution. Yet despite this wariness, children were still three times more likely to ignore or decline an inappropriate or unwanted request than they are to report or block it.

Steve Miller, Save the Children’s Global Director of Child Protection, said that children deserve to thrive in a safe and nurturing environment, both online and offline.

“As the digital landscape evolves, so do the challenges and threats, including the threat of online grooming and exploitation. We need to foster a digital environment that is not only safe but also enriching, allowing children to explore, learn, and grow without fear,” said Mr. Miller.

“Policymakers need to listen to the voices and experiences of children when developing policies that protect them.”

For more information, visit the Young and Resilient research Center’s “Protecting Children from Online Grooming” webpage here.

Extreme weather caused by shifts in a jet stream seems to have brought summers of fires, failed harvests and rampant disease across Europe over the past 700 years. That is the conclusion of an analysis of tree ring data, which also provides worrying clues for what the future holds under a changing climate.

Jet streams are bands of fast-moving winds high in the atmosphere, which blow around the world from west to east. The northern hemisphere polar jet influences weather conditions over Europe by…

A new report reveals the challenges mothers face trying to maintain a relationship with their children while in prison, and recommends additional support.

Dr. Kate O’Brien and Dr. Hannah King, from our Sociology department, evaluated the pioneering Parental Rights in Prison (PRiP) project. The PRiP project aimed to help incarcerated parents sustain a relationship with their children. The project provided specialist family support workers as well as legal advice and support.

It was run by the charity NEPACS and was piloted at HMP Low Newton women’s prison, Durham, before expanding to two men’s establishments in the region.

The evaluation found that the PRiP project was often the first-time incarcerated mothers received specialist family support and legal advocacy around their parental rights. Having a child/children removed often triggered self-medication, suicidal ideas and self-injury among mothers. This was especially the case early on in custody, and as mothers were approaching release.

PRiP helped to overcome issues of mothers being misinformed or given little/no information about the legal status of their children, or their parental rights.

The researchers made several recommendations to the Ministry of Justice and His Majesty’s Prison and Probation Service. These include:

• PRiP coordinators should be available to help all incarcerated mothers, supported by Family Law solicitors.
• PRiP coordinators should be enabled to work alongside other agencies, such as family support workers and drug and alcohol recovery teams, to provide coordinated support.
• Specialist support should be available for mothers upon release and during resettlement, including domestic abuse and sexual violence support.
• PRiP should be extended across male prisons too to work with fathers in prison.
• Specialist training and support should be provided for prison staff, social workers and Children’s Services to understand the challenges for mothers in prison.

The evaluation report also suggests further research should look at the needs of Black and racially minoritized mothers in custody.

Dr. O’Brien is working with NEPACs on ways to implement the recommendations from her report and is writing a book on parental rights in prison.

As part of the PRiP project, mothers also worked with a theater company, Open Clasp, to produce a performance called “Rupture,” based on their experiences. Their aim is to share the performance widely with prison staff and legal practitioners to help them understand the challenges faced by mothers in prison.

If you want to imagine a dinosaur running, then perhaps look at emus. They probably shared a similar posture, which makes it most energy efficient to keep one foot on the ground when running at an intermediate pace.

Pasha van Bijlert at Utrecht University in the Netherlands and his colleagues wanted to understand why birds have a style of running that is so different to humans.

For instance, emus (Dromaius novaehollandiae), which can sprint at up to 50 kilometres per hour, always have one foot on the ground when running at intermediate speeds. This was thought to require much more energy than the “aerial” running style, in which both feet are off the ground at the same time, which is seen in other bipeds, such as people.

To learn more, the scientists built a computer model based on an emu and used physics simulations to measure the energy output of different running styles, while varying the bird’s anatomy.

“These are all changes you can’t really make in a real bird, but they represent differences between different bird species,” says van Biljert. “For example, quails are very crouched and their tendons probably don’t store a lot of energy. Emus are, comparatively, pretty upright, but their tendons store a lot of energy.”

We tend to think of running as always having an aerial phase, says van Biljert. “However, [for emus] it goes like this: walking, grounded running, aerial running. So they have an extra running style at intermediate speeds. Grounded running appears to be a wasteful running style, because it costs more energy than aerial running.”

But in some cases, grounded running can optimise energy use, he says. “If your muscles are strongest in very crouched postures, and an upright posture is impossible, then there is a range of running speeds over which grounded running is actually your best choice. Humans don’t do this, because we can stand up straight, but birds can’t.”

Fossil evidence suggests that some dinosaurs had similar postures to the large running birds alive today. Velociraptors and Deinonychuses had relatively thin tails and long, feathered forelimbs, resulting in a forward shift to their centre of mass and a more crouched posture, says van Biljert. This resembles the stance of emus, he says.

“When explaining dinosaur locomotion to people who haven’t spent a lot of time thinking about such things, I jokingly like to say that the closest thing to a non-avian theropod dinosaur would be an emu with a crocodile tail.”

Jacqueline Nguyen at the Australian Museum in Sydney says the researchers’ model allowed them to conduct a virtual experiment that provides new insights.

“The authors suggest that grounded running in birds may have first evolved within non-avian dinosaurs,” says Nguyen. “This running mode may have been another bird feature that was inherited from their dinosaur ancestors, like bipedality, modified leg bones and feathers.”