Uncovering the secrets of ultra-low frequency gravitational waves

An artist's impression of the colliding bubbles that can produce extremely low frequency gravitational waves during a cosmological phase transition in the early Universe.
Image credit: Riccardo Buscicchio.

New methods of detecting ultra-low frequency gravitational waves can be combined with other, less sensitive measurements to deliver fresh insights into the early development of our universe, according to researchers at the University of Birmingham.

Gravitational waves - ripples in the fabric of Einstein's spacetime - that cross the universe at the speed of light have all sorts of wavelengths, or frequencies. Scientists have not yet managed to detect gravitational waves at extremely low ‘nanohertz’ frequencies, but new approaches currently being explored are expected to confirm the first low frequency signals quite soon.

The main method uses radio telescopes to detect gravitational waves using pulsars – exotic, dead stars, that send out pulses of radio waves with extraordinary regularity. Researchers at the NANOGrav collaboration, for example, use pulsars to time to exquisite precision the rotation periods of a network, or array, of millisecond pulsars – astronomers’ best approximation of a network of perfect clocks - spread throughout our galaxy. These can be used to measure the fractional changes caused by gravitational waves as they spread through the universe.

How can we eat without cooking the planet?

Oxford experts in the run up to the COP26 climate conference, Professor Jebb points out that agriculture accounts for more CO2 emissions than transportation, and she says ‘It is the single biggest cause of harm to nature.’   We need governments to make some structural changes in the food system, says Professor Jebb, but, meanwhile, we can all make a start by doing three things:    Avoid eating too much  Cut down on waste  Reduce consumption of meat and dairy

She says, some people have given up meat altogether but, Professor Jebb maintains, 'Although animals produce emissions, they are an important part of our agriculture eco-systems and provide important nutrients.'   But we need to reduce the global demand for meat, so countries that currently eat a lot of meat need to cut down. That would be good for health and the environment.  ‘Eating less meat will be  a win for people and the planet,’ she says.

Source/Credit: University of Oxford

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Genetic risk for clinical depression linked to physical symptoms

Dr Enda Byrne

People with higher genetic risk of clinical depression are more likely to have physical symptoms such as chronic pain, fatigue and migraine, University of Queensland researchers have found.

Dr. Enda Byrne from UQ’s Institute for Molecular Bioscience said depression was a serious disorder with lifetime risks of poor health.

“A large proportion of people with clinically-diagnosed depression present initially to doctors with physical symptoms that cause distress and can severely impact on people’s quality of life,” Dr. Byrne said.

“Our research aimed to better understand the biological basis of depression and found that assessing a broad range of symptoms was important.

“Ultimately, our research aimed to better understand the genetic risks and generate more accurate risk scores for use in research and healthcare.”

Despite recent breakthroughs, Dr. Byrne said finding additional genetic risk factors was difficult because of the variety of patient ages, their symptoms, responses to treatment and additional mental and physical disorders.

Invasive Species Increasingly Threaten Protected Areas Worldwide

China's famous Red Marshes, a protected area and vital shorebird
habitat that is increasingly being overrun by invasive grasses
that are smothering the red plants.
Photo credit: Hong'an Ding

The iconic “Red Beach” marshes of China’s Yellow Sea are a critical stopover for millions of shorebirds on their seasonal migrations along the East Asian-Australasian Flyway.

But in recent years, the vivid scarlet-hued native succulent plants that give the marshes their name are increasingly being overrun by non-native invasive grasses that are turning the marshes, which the Chinese government has set aside as a protected area, into a green desert avoided by shorebirds.

A new international study suggests similar scenarios may be playing out in many protected areas worldwide.

“Invasive species such as the cordgrass that is swamping native plants in the Red Marshes pose a much greater threat to protected areas, even well managed ones, than was previously recognized,” says Brian Silliman, Rachel Carson Distinguished Professor of Marine Conservation Biology at Duke University, who co-authored the study.

“Our findings suggest it may no longer be enough to defend these coastal areas of great ecological importance from disturbances by human activities,” says lead author Qiang He, a former postdoctoral researcher in Silliman’s lab who is now a professor of coastal ecology at Fudan University in China. “We also need to find better ways to protect them from biological invaders like cordgrass, which thrive in the open habitat of low-elevation mudflats that are a preferred habitat of shorebirds and common at many of these sites.”

Silliman, He and their colleagues published their peer-reviewed study Oct. 13 in the journal Science Advances. It was selected by the journal’s editors to be the issue’s cover article.

To conduct their study, the researchers used remote sensing to analyze 30 years of Google Earth Engine satellite images of wetlands inside and outside of seven of China’s largest protected coastal areas on the Yellow Sea, including several World Natural Heritage sites and Wetlands of International Importance sites.

By measuring and comparing the speed and extent of both wetland loss - typically caused by human disturbance – and cordgrass invasion at each site, they were able to construct a time-series dataset that shows native plants and habitats within the protected areas do receive protection, just not always enough.

“Although wetland loss due to human disturbance was significantly slower in all protected areas than in the unprotected control sites, plant invasions were much higher in four of the protected areas under invasion,” says He.

That finding confounds the prevailing theory that disturbance promotes species invasions, says Silliman.

“Compared to protected areas, unprotected sites often experience strong human disturbance, have more open habitats and are, thus, expected to be more vulnerable to invasions by exotic species,” he says. “We found it’s not that cut and dried.”

“Most importantly, our findings caution blind acceptance of the current conservation paradigm that protected areas will work well as long as human activities are managed effectively. This study shows that even if they are, invasive species can wreck that feel-good party,” he says. Silliman directs the Duke Restore initiative, which brings together researchers from science, engineering and policy to develop more effective tools and practices to combat habitat loss and enhance the resilience of natural and human systems in coastal areas. Qiang He is a visiting scholar in the program.

Their new study’s publication coincided with the 15th meeting of the Conference of the Parties (COP15) United Nations Convention on Biological Diversity in Kunming, China.

Leaders from more than 100 nations attended the meeting. They called for “urgent and integrated action” to increase the emphasis placed on biodiversity protection in all sectors of the global economy but stopped short of committing to specific targets to slow species loss, including a long-debated proposal to protect or conserve 30% of the land and ocean within their national territories by 2030.

Funding for the new study came from the National Natural Science Foundation of China and the National Key Research and Development Program of China.

Source/Credit: Duke University/Brian Silliman

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Carbon from a cosmic source

Partners in space: massive stars often occur in close binary systems in which one star takes mass from its companion. New research has now shown that these systems produce about twice as much carbon as individual, massive stars. © ESO/M. Kornmesser / S.E. de Mink

Computer simulations show that binary stars produce a large amount of this vital element

Many things work better in pairs. The production of chemical elements is no exception. Many elements are formed inside stars during fusion processes. Carbon plays an important role in this because it is the basis of life and thus ultimately of human beings. But how effective is the cosmic source of this important building block? A study led by the Max Planck Institute for Astrophysics shows that massive stars produce twice as much carbon when they have a companion star.

The researchers know that massive stars are essential in the synthesis of all heavy elements – from carbon and oxygen to iron. Although most of these stellar heavyweights are born in multiple star systems, previous models have looked almost exclusively at single stars. An international team led by Robert Farmer from the Max Planck Institute for Astrophysics in Garching has now calculated the carbon footprint of massive stars that are partners in a binary system.

The Butterfly Effect

Collected butterfly specimens from Torres Strait.
Image; Dr Trevor Lambkin

How Torres Strait Island butterflies could help conservation efforts

A University of Queensland researcher has spent decades compiling a first-of-its-kind database of the butterfly species of the Torres Strait Islands, boosting biosecurity and conservation measures in the region.

Dr Trevor Lambkin working in the field in Torres Strait.

Working closely with the Torres Strait Island Regional Council, Dr Trevor Lambkin said the database, listing 227 butterfly species will help local officials address the impacts of climate change, other human threats and weeds.

“My work has created detailed checklists and distribution maps of butterfly populations on each island for the first time, and this specific information will assist in future conservation measures,” Dr Lambkin said.

“As butterflies are prone to move from place to place, they’re very good yardsticks for use in predicting invasions of pest species.”

Dr Lambkin has made more than 30 visits to the islands over the past 38 years, discovering that several species of butterflies are now threatened by rising sea levels, directly linked to climate change.

“The threat of climate change requires urgent and well-directed conservation efforts to slow not only butterfly loss, but wider biodiversity loss,” he said.

One coronavirus vaccine may protect against other coronaviruses

Study is the first to demonstrate cross-protective immunity by vaccines

Northwestern Medicine scientists have shown for the first time that coronavirus vaccines and prior coronavirus infections can provide broad immunity against other, similar coronaviruses. The findings build a rationale for universal coronavirus vaccines that could prove useful in the face of future epidemics.

“Until our study, what hasn’t been clear is if you get exposed to one coronavirus, could you have cross-protection across other coronaviruses? And we showed that is the case,” said lead author Pablo Penaloza-MacMaster, assistant professor of microbiology-immunology at Northwestern University Feinberg School of Medicine.

The findings were recently published in the Journal of Clinical Investigation.

The three main families of coronaviruses that cause human disease are:

1. Sarbecovirus, which includes the SARS-CoV-1 strain that was responsible for the 2003 outbreak of Severe Acute Respiratory Syndrome (SARS), as well as SARS-CoV-2, which is responsible for COVID-19
2. Embecovirus, which includes OC43, which is often responsible for the common cold
3. Merbecovirus, which is the virus responsible for Middle East Respiratory Syndrome (MERS), first reported in 2012.

Vaccines demonstrated cross-protective immunity

Plasma from humans who had been vaccinated against SARS-CoV-2 produced antibodies that were cross-reactive (potentially providing protection) against SARS-CoV-1 and the common cold coronavirus (OC43), the study found. The study also found mice immunized with a SARS-CoV-1 vaccine developed in 2004 generated immune responses that protected them from intranasal exposure by SARS-CoV-2. Lastly, the study found prior coronavirus infections can protect against subsequent infections with other coronaviruses.

Scientists find evidence the early solar system harbored a gap between its inner and outer regions

An MIT study suggests that a mysterious gap existed within the solar system’s protoplanetary disk around 4.567 billion years ago, and likely shaped the composition of the solar system’s planets. This image shows an artist’s interpretation of a protoplanetary disk.
Credits:Credit: National Science Foundation, A. Khan

In the early solar system, a “protoplanetary disk” of dust and gas rotated around the sun and eventually coalesced into the planets we know today.

A new analysis of ancient meteorites by scientists at MIT and elsewhere suggests that a mysterious gap existed within this disk around 4.567 billion years ago, near the location where the asteroid belt resides today.

The team’s results, appearing today in Science Advances, provide direct evidence for this gap.

“Over the last decade, observations have shown that cavities, gaps, and rings are common in disks around other young stars,” says Benjamin Weiss, professor of planetary sciences in MIT’s Department of Earth, Atmospheric and Planetary Sciences (EAPS). “These are important but poorly understood signatures of the physical processes by which gas and dust transform into the young sun and planets.”

Likewise the cause of such a gap in our own solar system remains a mystery. One possibility is that Jupiter may have been an influence. As the gas giant took shape, its immense gravitational pull could have pushed gas and dust toward the outskirts, leaving behind a gap in the developing disk.

Contraceptive pill can reduce type 2 diabetes risk in women with polycystic ovary syndrome

A study led by the University of Birmingham has revealed for the first time that the contraceptive pill can reduce the risk of type 2 diabetes by over a quarter in women with polycystic ovary syndrome (PCOS).

The research findings also show that women with PCOS have twice the risk of developing type 2 diabetes or pre-diabetes (dysglycemia) – highlighting the urgent need to find treatments to reduce this risk.

In addition to the risk of type 2 diabetes, PCOS – which affects 10% of women world-wide - is also associated with a number of other conditions in the long-term, such as endometrial cancer, cardiovascular disease, and non-alcohol related fatty liver disease (NAFLD).

Symptoms of PCOS include irregular periods or no periods at all, which can lead to fertility issues, and many suffer from unwanted hair growth (known as ‘hirsutism’) on the face or body, hair loss on the scalp, and oily skin or acne. These symptoms are caused by high levels of hormones called androgens in the blood of women with PCOS.

Women with PCOS also often struggle with weight gain and the cells in their body are often less responsive to insulin – the hormone that allows the body to absorb glucose (blood sugar) into the cells for energy. This reduced response to insulin can lead to elevated blood glucose levels and can cause the body to make more insulin, which in turn causes the body to make more androgens. The androgens further increase insulin levels - driving a vicious circle.

A decade after gene therapy

Evangelina Vaccaro, above, who received the gene therapy
 for ADA-SCID in a clinical trial in 2012.
Credit: Courtesy of Alysia Padilla-Vaccaro

Over a decade ago, UCLA physician-scientists began using a pioneering gene therapy they developed to treat children born with a rare and deadly immune system disorder. They now report that the effects of the therapy appear to be long-lasting, with 90% of patients who received the treatment eight to 11 years ago still disease-free.

ADA-SCID, or adenosine deaminase–deficient severe combined immunodeficiency, is caused by mutations in the gene that creates the ADA enzyme, which is essential to a functioning immune system. For babies with the disease, exposure to everyday germs can be fatal, and if untreated, most will die within the first two years of life.

In the gene therapy approach detailed in the new paper, Dr. Donald Kohn of UCLA and his colleagues removed blood-forming stem cells from each child’s bone marrow, then used a specially modified virus, originally isolated from mice, to guide healthy copies of the ADA gene into the stem cells’ DNA. Finally, they transplanted the cells back into the children’s bone marrow. The therapy, when successful, prompts the body to produce a continuous supply of healthy immune cells capable of fighting infections. Because the transplanted stem cells are the baby’s own, there is no risk of rejection.