Urban gardens are a dependable food source for pollinators through the year

A nectar-rich garden in Westbury Park (Bristol).
Credit: Nick Tew

Gardens in cities provide a long and continuous supply of energy-rich nectar from March to October, scientists at the University of Bristol have found.

Despite huge garden-to-garden variation in both the quantity and timing of nectar production, pollinators are guaranteed a reliable food supply if they visit multiple gardens. This contrasts with previous studies on farmland, where pollinators are exposed to boom-and-bust cycles of nectar production with clear seasonal gaps.

This means the actions of many independent gardeners result in the emergent property of a stable and diverse provision of food for city pollinators.

PhD student Nick Tew from the School of Biological Sciences said: “We measured the amount of nectar produced by flowers in 59 residential gardens in Bristol. We found that individual gardens vary in both how much food they provide and when they provide it during the year. However, because flying pollinators like bees can visit many different gardens, they are likely to be able to find food in residential neighborhoods whenever they need it.

“We knew that gardens were important habitats for pollinators, providing 85% of nectar sugar in urban landscapes and a great diversity of flowering plants. However, we did not know how nectar production varied between individual gardens or through the months of the year. It is particularly important to understand garden-to-garden variation to advise how best to collectively manage our gardens for pollinators.”

The variation between gardens was extreme, ranging from 2g to 1.7kg of nectar sugar through the year and this was not determined by the size of the garden but rather by how people chose to manage their gardens.

Superbug MRSA arose in hedgehogs long before clinical use of antibiotics

Scientists have found evidence that a type of the antibiotic resistant superbug MRSA arose in nature long before the use of antibiotics in humans and livestock, which has traditionally been blamed for its emergence.

Staphylococcus aureus first developed resistance to the antibiotic methicillin around 200 years ago, according to a large international collaboration including the University of Cambridge, the Wellcome Sanger Institute, Denmark’s Serum Statens Institut, University of Oxford and the Royal Botanic Gardens, Kew, which has traced the genetic history of the bacteria.

They were investigating the surprising discovery - from hedgehog surveys from Denmark and Sweden - that up to 60% of hedgehogs carry a type of MRSA called mecC-MRSA. The new study also found high levels of MRSA in swabs taken from hedgehogs across their range in Europe and New Zealand.

The researchers believe that antibiotic resistance evolved in Staphylococcus aureus as an adaptation to having to exist side-by-side on the skin of hedgehogs with the fungus Trichophyton erinacei, which produces its own antibiotics.

The resulting methicillin-resistant Staphylococcus aureus is better known as the superbug MRSA. The discovery of this centuries-old antibiotic resistance predates antibiotic overuse in medical and agricultural settings.

'Using sequencing technology we have traced the genes that give mecC-MRSA its antibiotic resistance all the way back to their first appearance, and found they were around in the nineteenth century,' said Dr Ewan Harrison, a researcher at the Wellcome Sanger Institute and University of Cambridge and a senior author of the study.

Researchers Pinpoint Which Bird Species Pose Food Safety Risk to Crops

Concerns over foodborne risk from birds may not be as severe as once thought by produce farmers, according to research from the University of California, Davis, that found low instances of E. coli and Salmonella prevalence.

While the research found that the risk is often low, it varies depending on species. Birds like starlings that flock in large numbers and forage on the ground near cattle are more likely to spread pathogenic bacteria to crops like lettuce, spinach and broccoli, according to the study of food safety risk and bird pathogens. In contrast, insect-eating species were less likely to carry pathogens.

The findings, published in the journal Ecological Applications, suggest that current practice of removing bird habitats around produce growers’ farms over concerns the animals could bring foodborne pathogens into their fields may not solve the problem.

“Farmers are increasingly concerned that birds may be spreading foodborne diseases to their crops,” said Daniel Karp, the senior author on the study and an assistant professor in the UC Davis Department of Wildlife, Fish and Conservation Biology. “Yet not all bird species are equally risky.”

Only one foodborne disease outbreak in produce has been conclusively traced to birds: a Campylobacter outbreak in peas from Alaska. While the bacteria can cause diarrhea and other foodborne illness in humans, it’s less of a concern to growers than E. coli and Salmonella, which have been responsible for multiple outbreaks across the nation.

In this study, researchers compiled more than 11,000 bacteria tests of wild bird feces and found that Campylobacter was detected in 8 percent of samples. But pathogenic E. Coli and Salmonella were only found in very rare cases (less than 0.5%).

First-responder cells after heart attack prompt inflammation overdrive

First-responder cells launching the repair after a heart attack are so frantic about fixing the damage that they promote more inflammation than necessary, new research in mice suggests.

Based on those findings, scientists are pursuing interventions that would bring more balance to the healing process after a heart attack.

In a series of studies, the researchers have identified the cellular events that lead to a call for reinforcements – an extra wave of the first responders – to the site of repair. This process leads to the release of proinflammatory proteins at a point when they aren’t needed, creating conditions that may threaten optimum healing of the heart.

The first-responder cells in question are neutrophils, the most abundant of all white blood cells whose job is to heal wounds and clear away infection. Researchers are exploring potential drugs or genetic techniques that could block the call for neutrophil backups or limit the release of proteins that drive up inflammation.

“We just want to prevent further damage that happens to the heart by toning down the neutrophil response,” said Prabhakara Nagareddy, associate professor of cardiac surgery in The Ohio State University College of Medicine. “The neutrophils are misguided and they overreact. How can we tame them? How can we bring that down?

“We started looking at the role of inflammation in scar formation to see if we could potentially alter that process.”

The most recent study on this work is published in the Jan. 4, 2022, issue of the journal Circulation.

Adding the Right Amount of Sediment to Salt Marshes Keeps Coastlines Afloat

Anna Puchkoff in the field conducting a study on sediment distribution in Connecticut wetlands.
Image Source: University of Connecticut

Adding just the right amount of sediment to the surface of a Connecticut salt marsh protects coastlines by promoting rapid plant growth, scientists from the University of Connecticut report in a new study published recently in Environmental Engineering.

Adding sediment on top of salt marshes helps them stay above sea level as it continues to rise. Anna Puchkoff and Beth Lawrence from UConn’s College of Agriculture, Health and Natural Resources conducted a study on how the addition of sediment could restore salt marshes in Connecticut. For her research, Puchkoff used sediment that was dredged from the Long Island Sound by the nearby Guilford Yacht Club.

“My goal was to also reduce project costs and replicate a real-life restoration scenario where in many cases, you have to work with what you’ve got or what the available resources at hand are,” says Puchkoff, who recently earned a master’s degree from the Department of Natural Resources and the Environment at UConn. “This was a core principle in my research, since using dredged material from marinas is common and disposal is costly.”

New test can identify if a patient has cancer and if it has spread

A University of Oxford study published in Clinical Cancer Research, a journal of the American Association for Cancer Research, outlines a new type of blood test that can be used to detect a range of cancers and whether these cancers have spread (metastasized) in the body.

The study analyzed samples from 300 patients with non-specific but concerning symptoms of cancer, such as fatigue and weight loss, who were recruited through the Oxfordshire Suspected CANcer (SCAN) pathway.

The researchers assessed whether the test could distinguish patients with a range of solid tumors from those without cancer. Their results show that cancer was correctly detected in 19 out of every 20 patients with cancer using this test. In those with cancer, metastatic disease was identified with an overall accuracy of 94%. These results make this the first technology to be able to determine the metastatic status of a cancer from a simple blood test, without prior knowledge of the primary cancer type.

This test shows promise to help clinicians detect cancer and assess cancer stage in the future. Unlike many blood-based tests for cancer, which detect genetic material from tumors, this test uses a technique called NMR metabolomics, which uses high magnetic fields and radio waves to profile levels of natural chemicals (metabolites) in the blood.

Healthy individuals, people with localized cancer, and people with metastatic cancer each have different profiles of blood metabolites, which can be detected and then analyzed by the researchers’ algorithms to distinguish between these states.

Mass die-off of Magellanic penguins seen during 2019 heat wave

UW doctoral student Katie Holt examining adult Magellanic penguin corpses (circled) at Punta Tombo just after the Jan. 19, 2019 heat wave. Just over one-quarter of adult Magellanic penguin bodies were found between the colony and the ocean, indicating that they likely perished trying to get to the water.
Credit: Anna Sulc/University of Washington

In June 2021, an unprecedented heat wave hit the Pacific Northwest and Canada, killing an estimated 1,400 people. On June 28, Seattle reached 108 F — an all-time high — while the village of Lytton in British Columbia recorded Canada’s highest-ever temperature of 121.3 F on June 29, the day before it was destroyed by a heat-triggered wildfire.

Climate change is expected to bring more such extreme heat events globally, with far-reaching consequences not just for humans, but for wildlife and ecosystems.

In 2019, University of Washington researchers witnessed this in Argentina at one of the world’s largest breeding colonies for Magellanic penguins. On Jan. 19, temperatures at the site in Punta Tombo, on Argentina’s southern coast, spiked to 44 C, or 111.2 F, and that was in the shade. As the team reports in a paper published Jan. 4 in the journal Ornithological Applications, the extreme heat wave killed at least 354 penguins, based on a search for bodies by UW researchers in the days following the record high temperature.

Measurements of trees’ impact on 5G transmissions could prove vital to using a new class of signal.

NIST researchers studied the effects of trees on millimeter waves,
which are planned for use in 5G communication. 
Credit: N. Hanacek/NIST

As 5G technology gets fully implemented over the next several years, cellphones and other wireless tech will grow more powerful with increased data flow and lower latency. But along with these benefits comes a question: Will your next-generation cellphone be unable to see the forest for the trees?

That’s one way to describe the problem confronting cell network designers, who have to embrace both the benefits and shortcomings of a new class of signals that 5G will use: millimeter waves. Not only can these waves carry more information than conventional transmissions do, but they also usefully occupy a portion of the broadcast spectrum that communication technologies seldom use — a major concern in an age when broadcasters vie for portions of spectrum like prospectors staking out territory.

However, millimeter waves also have drawbacks, including their limited ability to penetrate obstacles. These obstacles include buildings, but also the trees that dot the landscape. Until recently little was known about how trees affected millimeter wave propagation. And just as few of us would want to imagine a landscape without greenery, few designers would be able to plan networks around it without such a crucial fundamental detail.

The National Institute of Standards and Technology (NIST) has set out to solve this problem by measuring trees’ effect on millimeter waves. The effort could make a profound difference in our next-generation devices’ ability to see the 5G antennae that may soon sprout.

The 5G era will feature wireless communication not only between people but also between devices connected to the Internet of Things. The increased demand for larger downloads by cell customers and lag-free network response by gamers has spurred the wireless industry to pursue speedier, more effective communication. Not only could our current devices and services work more effectively, but we could realize new ones: Autonomous vehicles will depend on such quick network response to function.

Resolving the black hole ‘fuzzball or wormhole’ debate

Black holes really are giant fuzzballs, a new study says.

The study attempts to put to rest the debate over Stephen Hawking’s famous information paradox, the problem created by Hawking’s conclusion that any data that enters a black hole can never leave. This conclusion accorded with the laws of thermodynamics, but opposed the fundamental laws of quantum mechanics.

“What we found from string theory is that all the mass of a black hole is not getting sucked in to the center,” said Samir Mathur, lead author of the study and professor of physics at The Ohio State University. “The black hole tries to squeeze things to a point, but then the particles get stretched into these strings, and the strings start to stretch and expand and it becomes this fuzzball that expands to fill up the entirety of the black hole.”

The study, published Dec. 28 in the Turkish Journal of Physics, found that string theory almost certainly holds the answer to Hawking’s paradox, as the paper’s authors had originally believed. The physicists proved theorems to show that the fuzzball theory remains the most likely solution for Hawking’s information paradox. The researchers have also published an essay showing how this work may resolve longstanding puzzles in cosmology; the essay appeared in December in the International Journal of Modern Physics.

Mathur published a study in 2004 that theorized black holes were similar to very large, very messy balls of yarn – “fuzzballs” that become larger and messier as new objects get sucked in.

Solving the disappearance of bears and lions with ancient DNA

Brown bears (or grizzly bears) mysteriously disappeared from some parts of North America for thousands of years prior to the last Ice Age and later reappeared, walking from Russia to Alaska across the Bering Land Bridge. Researchers suggest climate change could be the reason why.
Photo Credit: Vincent M.A. Janssen

An international team of researchers led by the University of Adelaide, suggest a change in climate is the likely cause of the mysterious disappearance of ancient lions and bears from parts of North America for a thousand years or more prior to the last Ice Age.

In a study in Molecular Ecology , the researchers sequenced DNA from fossils of cave lions and bears from North America and Eurasia to better understand the timing and drivers of their past movement between continents.

Co-author, Dr Kieren Mitchell from the University of Adelaide’s Australian Centre for Ancient DNA said, “There's a common perception that outside of mass extinctions or direct human interference, ecosystems tend to remain stable over thousands or even millions of years.

“As illustrated by our study of the fossil record, that's not necessarily the case.

“Previous research has shown that brown bears (or grizzly bears) disappeared from some parts of North America for thousands of years prior to the last Ice Age. They later reappeared, walking from Russia to Alaska across the Bering Land Bridge – possibly at the same time as people moved across the Bridge into North America too.