There is growing scientific and public interest in the AMOC, a three-dimensional system of ocean currents that act as a “conveyer belt” to distribute heat, salt, nutrients, and carbon dioxide across the world’s oceans. Changes in the AMOC’s strength could impact global and regional climate, weather, sea level, precipitation patterns, and marine ecosystems.

In this research, measurements of the Florida Current were corrected for the secular change in the geomagnetic field to find that the Florida Current, one of the fastest currents in the ocean and an important part of the AMOC, has remained remarkably stable over the past 40 years.

The study published in the journal Nature Communications, the scientists reassessed the 40-year record of the Florida Current volume transport measured on a decommissioned submarine telecommunications cable in the Florida Straits, which spans the seafloor between Florida and the Bahamas. Due to the Earth’s magnetic field, as salt ions in the seawater are transported by the Florida Current over the cable, a measurable voltage is induced in the cable. The cable measurements were analyzed together with measurements from regular hydrographic surveys that directly measure the Florida Current volume transport and water mass properties. In addition, the transport was inferred from cross-stream sea level differences measured by altimetry satellites.

“This study does not refute the potential slowdown of AMOC, it shows that the Florida Current, one of the key components of the AMOC in the subtropical North Atlantic, has remained steady over the more than 40 years of observations,” said Denis Volkov, lead author of the study and a scientist at CIMAS which is based at the Rosenstiel School. “With the corrected and updated Florida Current transport time series, the negative tendency in the AMOC transport is indeed reduced, but it is not gone completely. The existing observational record is just starting to resolve interdecadal variability, and we need many more years of sustained monitoring to confirm if a long-term AMOC decline is happening.”

Understanding the state of the Florida Current is very important for developing coastal sea level forecast systems, assessing local weather and ecosystem and societal impacts.

Since 1982, NOAA’s Western Boundary Time Series (WBTS) project and its predecessors have monitored the transport of the Florida Current between Florida and the Bahamas at 27°N using a 120-km long submarine cable paired with regular hydrographic cruises in the Florida Straits. This nearly continuous monitoring has provided the longest observational record of a boundary current in existence. Beginning in 2004, NOAA’s WBTS project partnered with the United Kingdom’s Rapid Climate Change program (RAPID) and the University of Miami’s Meridional Overturning Circulation and Heatflux Array (MOCHA) programs to establish the first trans basin AMOC observing array at about 26.5N.

The study was supported by NOAA ‘s Global Ocean Monitoring and Observing program (grant #100007298), NOAA’s Climate Variability and Predictability program (grant #NA20OAR4310407), Natural Environment Research Council (grants #NE/Y003551/1 and NE/Y005589/1) and the National Science Foundation (grants #OCE-1332978 and #OCE-1926008).

The report, published in The Lancet Planetary Health, outlines how cities and businesses have the power to play a crucial role and become the “stewards” of critical Earth systems by demonstrating how they can reduce their environmental impact on the planet. The report summarises key findings of phase one of Earth Commission, founded in 2019 with a team of 18 globally esteemed interdisciplinary scholars as commissioners, involving more than 40 researchers in various working groups.

The report builds on the Safe and Just Earth System Boundaries report published in Nature last year, which found that most of the vital limits within which people and the planet can thrive have been surpassed.

One of three lead authors, Distinguished Professor Xuemei Bai, from ANU, who led the working group on Translation, said that companies and cities have the means to act and drastically transform and reduce pressure on the planet.

“Companies and cities have a huge potential to make a difference, especially if they work towards the same goal, which is to ensure the planet can provide for everyone long-term,” she said.

“They are more nimble and flexible than states, and can reduce their pressure on the planet by setting science-based targets in line with our findings.”

Professor Stuart Bunn, from Griffith University, co-led one of the working groups, which focused on the boundaries of freshwater and nutrient pollution.

The report found the planet’s ability to provide and protect is being stretched past its limits, although it remains possible for humans to escape poverty and harm caused by Earth’s system change, if urgent action is taken.

It found the only way to provide for everyone and ensure societies, businesses and economies thrive without destabilising the planet is to reduce inequalities in how critical Earth system resources, such as freshwater and nutrients, are accessed and used, and how responsibilities, such as reducing carbon emission, are shared, alongside economic and technological transformation.

By 2050, unless urgent transformations are made, the researchers argue that Earth’s climate will deteriorate to the point where there will be no “safe and just space” left.

That means that even if everyone on the planet only had access to the resources necessary for a basic standard of living in 2050, the Earth would still be outside the climate boundary.

The researchers say earth systems face the risk of crossing dangerous tipping points, which would cause further significant harm to people around the world unless energy, food and urban systems are urgently transformed.

The paper outlines a series of recommendations to ensure Earth’s climate remains within this so-called “safe and just space.”

• Firstly, a well-coordinated, intentional effort between policymakers, businesses, civil society and communities can push for changes in how we run the economy and find new policies and funding mechanisms that can address inequality whilst reducing pressure on nature and climate.

• Secondly, fundamental to the transformation is more efficient and effective management, sharing and usage of resources at every level of society including addressing the excessconsumption of some communities, which limits access to basic resources for those whoneed them the most.

• Thirdly, investment in sustainable and affordable technologies is essential to help us use fewer resources and to reopen the safe and just space for all, particularly where there is little or no space left.

The report has been published in The Lancet Planetary Health. It is co-authored by more than 60 leading natural and social scientists from across the globe.

The Duffy-null phenotype results in relatively lower levels of white blood cells called neutrophils when measured in the blood. This is not because they have less neutrophils overall, but because they are more frequently located in other body tissues. Tests that restrict clinical trial eligibility to patients with certain blood levels of neutrophils may therefore be unfairly discriminating against patients who could potentially benefit from trial therapies.

The failure to account for Duffy-null phenotype also means that recommendations for many standard cancer drugs inappropriately call for less-effective doses for some individuals, researchers say.

Tests that count neutrophils in a blood sample are performed to ensure that patients can safely be treated with chemotherapy or other anti-cancer drugs. Levels of neutrophils, white blood cells that kill bacteria and other foreign microbes, are often reduced by cancer drugs, potentially raising the risk of infection. For patients to qualify for a clinical trial or a standard dose of many cancer drugs, their neutrophil levels need to be above a certain threshold to ensure they will retain enough of these cells following treatment.

The threshold was established by studies conducted primarily in patients of European descent who rarely have the Duffy-null phenotype. Many healthy people with the Duffy-null phenotype (mostly people of African and Middle Eastern ancestry), however, normally have lower levels of neutrophils in their blood and relatively higher levels in their other tissues.

“Natural variation in neutrophil counts between people of different ancestry has been historically described by the inaccurate and now-outdated diagnosis ‘benign ethnic neutropenia,'” says Stephen Hibbs of Queen Mary University of London, who led the study, published today by JAMA Network Open, and for which Dana-Farber’s Andrew Hantel, MD is senior author. “But since this variation was discovered to be caused by the Duffy null phenotype, we need to re-examine the ways in which neutrophil count misinterpretation can affect patient care.”

“People with the Duffy-null phenotype are equally able to fight off infections compared to others,” Hantel says. “The concern is that they’ve been excluded from clinical trials because the neutrophil blood levels that are normal for them can fall below the cut-off points for trial participation. In this study, we explored the extent to which this occurs.”

The researchers examined participation criteria for 289 major phase III trials of drugs for the five most prevalent cancers in the United States and United Kingdom: prostate, breast, colorectal, and lung cancer, and melanoma. The drugs included chemotherapy agents, targeted therapies, and hormonal therapies (which generally don’t decrease neutrophil levels).

They found that 76.5% of the trials excluded patients whose blood neutrophil counts were in the normal range for people with the Duffy-null phenotype. The trials with the highest exclusion rate — 86.4% — were for patients with colorectal cancer. Even trials of hormonal cancer therapies — which generally don’t decrease neutrophil levels — had a significant exclusion rate.

The researchers also examined the extent to which clinical trial protocols require that drug doses be modified for patients with lower neutrophil counts.

“The treatment guidelines set by the National Comprehensive Cancer Network, or NCCN, are based on the clinical trials in which those drugs were tested,” Hantel explains. “If a trial stipulates that the dosage should be lowered or delayed if a patient’s blood neutrophil count is below a certain level, doctors often use those modifications once the drug is approved as standard therapy. We know that in many cases, survival rates are lower for patients who receive lowered or delayed doses.”

The researchers reviewed 71 clinical trials that led to NCCN recommended treatment regimens. They found that more than half required reducing the drug dose, delaying its administration, or stopping it if a participant’s neutrophil count fell below a level that was still normal for people with the Duffy null phenotype. When they looked at recommended changed based on individual Food and Drug Administration labels for each therapy used, a similar rate of dose changes was seen.

“The effect of these recommendations is to inappropriately reduce the intensity of treatment for patients who would likely tolerate regular doses,” Hantel says.

Based on their findings, the researchers recommend that clinical trials of cancer drugs allow entry to patients with lower, but normal-for-them neutrophil counts. “Everyone being screened for trial entry should be tested for the Duffy-null phenotype. If they are Duffy-null and their counts are in the reference range for that group, they should be admitted,” Hantel remarks.

For current and future trials, the same principle should be used in determining whether trial participants require lower or delayed doses: people with Duffy-null phenotype whose neutrophils are in their healthy range should be eligible for full doses of the study drug. For trials that have already been completed, follow-up studies are needed to determine if administering full doses to people with Duffy-null phenotype and lower neutrophils counts are safe and effective, researchers say.

“Health inequity in cancer treatment and research has many causes, and some are more difficult to address than others. Neutrophil criteria for clinical trials and dose modifications are a hidden contributor to inequity that can be rectified. Now, action to amend these criteria is needed to ensure Duffy-null patients are not disadvantaged,” said Hibbs.

The study was funded by the National Institutes of Health, the American Society for Clinical Oncology, and the Wellcome Trust.

In what the researchers say in Scientific Reports is the first time for a non-human animal to be demonstrated to possess some mental states (e.g., mental body image, standards, intentions, goals) which are elements of private self-awareness, bluestreak cleaner wrasse (Labroides dimidiatus) checked their body size in a mirror before choosing whether to attack fish that were slightly larger or smaller than themselves.

The team of OMU Graduate School of Science student Taiga Kobayashi, Specially Appointed Professor Masanori Kohda, Professor Satoshi Awata, and Specially Appointed Researcher Shumpei Sogawa, and Professor Redouan Bshary of Switzerland’s University of Neuchâtel, were among the group that last year reported the cleaner wrasse could identify photographs of itself as itself, based on its face through mirror self-recognition.

This time, the cleaner wrasse’s behavior of going to look in the mirror installed in a tank when necessary indicated the possibility that the fish were using the mirror to check their own body size against that of other fish and predict the outcome of fights.

“The results that fish can use the mirror as a tool can help clarify the similarities between human and non-human animal self-awareness and provide important clues to elucidate how self-awareness has evolved,” doctoral candidate Kobayashi declared.

This study was financially supported by JST SPRING (JPMJSP2139 to T.K.), JSPS KAKENHI (23KJ1829 to T.K., 19F19713 and 20K20630 to M.K., 22H02703 to S.A., and 20K20154 to S.S.), Swiss Science Foundation (310030_192673 to R.B.), and an OCU Strategic Research Grant 2018-2019 (to M.K. and S.A.).

Pathogens can be airborne, but little is known about the diversity of microbes that can survive at very high altitudes, where the conditions are harsh. “We know that above a certain point in the troposphere (called the planetary boundary layer), certain materials can be transported over long distances because the air in that region is isolated from the surface and there is less friction. But we did not suspect that viable microorganisms could be there also,” says Xavier Rodó, ICREA researcher at ISGlobal.

“Our study is unique in that we performed 10 tropospheric flights to examine microbial diversity at high altitudes, while most studies have been performed only a few metres above the ground or the ocean,” he adds.

Airborne microbes high above Japan

Using a Cessna aircraft, Rodó and an international team of colleagues conducted ten air surveys between 1,000 and 3,000 metres above Japan, starting from Chofu airport near Tokyo. All flights were planned to follow wind currents coming from mainland Asia in what are known as tropospheric bridges, which connect air from distant regions of the world; in this case, air that uplifts in mainland China and then descends over Tokyo due to typical winter weather conditions. For comparison, samples were also collected on the ground at Chofu. A total of 22 aerosol filter samples, collected during two periods (February and April, 2014), were analysed for their chemical and biological composition.

DNA sequencing allowed the research team to identify over 266 fungal and 305 bacterial genera associated with the aerosols, some of which are potentially pathogenic for humans, other animals or plants. For instance, bacterial species such as Escherichia coli, Serratia marcescens, Clostridium difficile, Clostridium botulinum, Haemophillus parainfluenzae, Acinetobacter baumannii and several Staphylococcus species were identified, as well as fungal species from genera such as Candida, Cladosporium and Malassezia, capable of causing disease in susceptible and immunocompromised individuals.

By culturing some of the samples, the researchers showed that bacteria collected from the air remained viable, and that some were resistant to commonly used antibiotics. “Surprisingly, the Micrococcus luteus strain isolated was resistant to multiple drugs, including carbapenems, glycopeptides, ciprofloxacin, and trimethoprim-sulfamethoxazole. Our findings suggest that antimicrobial resistance could spread over long distances via this previously unrecognised route,” says Sofya Podzniakova, co-first author of the study.

Travelling thousands of kilometres

The association of these aerosols with certain elements such as zinc sulfate and potassium, commonly used in fertilizers and pesticides, suggests an agricultural origin, consistent with intensively farmed croplands in northeast China.

Finally, during the days sampled, flight and ground samples were very similar in terms of microbial diversity, which can be explained by air descending from high altitudes to the ground. The particle transport models, simulated by Roger Curcoll -currently a researcher at the Universitat Politècnica de Catalunya — BarcelonaTech (UPC)- have corroborated both the possible transport of these particles from northeast China and the decline of tropospheric air masses to land in Japan.

“Our findings uncover a rich and unprecedented diversity of microbes that are dispersed by wind currents thousands of kilometres away from their sources by intense tunnels of wind that form high in the troposphere,” says Rodó. “They represent a paradigm shift in our understanding of how human health can be affected by pathogens thriving in the environment, particularly in the air.”

While the study does not prove a causal link between the presence of known human pathogens in aerosols and health effects, it does emphasise the need to further explore the spread of different microbial pathogens over long distances.