That’s a tricky feat. The Arctic spans thousands of miles, many of them inaccessible to humans. This inaccessibility has limited most ground-based observations to places with existing infrastructure — a mere fraction of the vast and varied Arctic terrain. Moreover, satellite observations are not detailed enough for scientists to identify key patterns and smaller-scale environmental influences on methane concentrations.

In a new study, scientists with NASA’s Arctic Boreal Vulnerability Experiment (ABoVE), found a way to bridge that gap. In 2017, they used planes equipped with the Airborne Visible Infrared Imaging Spectrometer — Next Generation (AVIRIS — NG), a highly specialized instrument, to fly over some 20,000 square miles (30,000 square kilometers) of the Arctic landscape in the hope of detecting methane hotspots. The instrument did not disappoint.

“We consider hotspots to be areas showing an excess of 3,000 parts per million of methane between the airborne sensor and the ground,” said lead author Clayton Elder of NASA’s Jet Propulsion Laboratory in Pasadena, California. “And we detected 2 million of these hotspots over the land that we covered.”

The paper, titled “Airborne Mapping Reveals Emergent Power Law of Arctic Methane Emissions,” was published Feb. 10 in Geophysical Research Letters.

Within the dataset, the team also discovered a pattern: On average, the methane hotspots were mostly concentrated within about 44 yards (40 meters) of standing bodies of water, like lakes and streams. After the 44-yard mark, the presence of hotspots gradually became sparser, and at about 330 yards (300 meters) from the water source, they dropped off almost completely.

The scientists working on this study don’t have a complete answer as to why 44 yards is the “magic number” for the whole survey region yet, but additional studies they’ve conducted on the ground provide some insight.

“After two years of ground field studies that began in 2018 at an Alaskan lake site with a methane hotspot, we found abrupt thawing of the permafrost right underneath the hotspot,” said Elder. “It’s that additional contribution of permafrost carbon — carbon that’s been frozen for thousands of years — that’s essentially contributing food for the microbes to chew up and turn into methane as the permafrost continues to thaw.”

Scientists are just scratching the surface of what is possible with the new data, but their first observations are valuable. Being able to identify the likely causes of the distribution of methane hotspots, for example, will help them to more accurately calculate this greenhouse gas’s emissions across areas where we don’t have observations. This new knowledge will improve how Arctic land models represent methane dynamics and therefore our ability to forecast the region’s impact on global climate and global climate change impacts on the Arctic.

Elder says the study is also a technological breakthrough.

“AVIRIS-NG has been used in previous methane surveys, but those surveys focused on human-caused emissions in populated areas and areas with major infrastructure known to produce emissions,” he said. “Our study marks the first time the instrument has been used to find hotspots where the locations of possible permafrost-related emissions are far less understood.”

More information on ABoVE can be found here:

https://above.nasa.gov/

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Materials provided by NASA/Jet Propulsion Laboratory. Original written by Esprit Smith. Note: Content may be edited for style and length.

And while travel bans are frequently used to stop the spread of an emerging infectious disease, a new University of Washington and Johns Hopkins University study of published research found that the effectiveness of travel bans is mostly unknown.

However, said lead author Nicole Errett, a lecturer in the UW Department of Environmental & Occupational Health Sciences in the School of Public Health, that’s largely due to the fact that very little research into the effectiveness of travel bans exists.

“Some of the evidence suggests that a travel ban may delay the arrival of an infectious disease in a country by days or weeks. However, there is very little evidence to suggest that a travel ban eliminates the risk of the disease crossing borders in the long term,” said Errett, co-director of the ColLABorative on Extreme Event Resilience, a research lab focused on addressing real-world issues relevant to community resilience.

The researchers combed through thousands of published articles in an effort to identify those that directly addressed travel bans used to reduce the geographic impact of the Ebola virus, SARS (Severe Acute Respiratory Syndrome), MERS (Middle East Respiratory Syndrome) and the Zika virus. They did not include studies of influenza viruses, for which travel bans have already been shown to be ineffective in the long term.

In the end, the researchers were able to identify just six studies that fit their criteria. Those six were based on models or simulations, not data from actual bans after they were implemented, to assess the effectiveness of travel bans in controlling outbreaks. Consequently, to improve research in this area, the study authors recommend that research questions, partnerships and study protocols be established ahead of the next outbreak so empirical data can be collected and assessed quickly.

“Travel bans are one of several legal options that governments have drawn on to mitigate a pandemic,” said co-author Lainie Rutkow, a professor of health policy and management at Johns Hopkins Bloomberg School of Public Health. “As coronavirus spreads, our study raises the importance of understanding the effectiveness of legal and policy responses intended to protect and promote the public’s health.”

“When assessing the need for, and validity of, a travel ban, given the limited evidence, it’s important to ask if it is the least restrictive measure that still protects the public’s health, and even if it is, we should be asking that question repeatedly, and often,” said co-author Lauren Sauer, an assistant professor of emergency medicine at Johns Hopkins University’s School of Medicine and director of operations with the university’s Office of Critical Event Preparedness and Response.

Consequently, the authors write, additional research is “urgently needed” to inform policy decisions, especially in light of the tremendous social, economic and political impacts of their implementation.

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Materials provided by University of Washington. Original written by Jake Ellison. Note: Content may be edited for style and length.

About 30 percent of soldiers who fought in the 1991 Gulf War suffer from GWI. Veterans with GWI display a range of symptoms, including fatigue, chronic pain and cognitive problems such as memory loss. The cause of GWI is unknown, but several potential culprits are suspected. They include exposure to nerve gas, as well as medicine given to protect against this neurotoxin; exposure to pesticides; and the stress of extreme temperature changes, sleep deprivation and physical exertion during deployment

Many of the symptoms of GWI overlap with those of another condition, fibromyalgia, notes the senior author of the study, Marco Loggia, PhD, whose laboratory at MGH’s Athinoula A. Martinos Center for Biomedical Imaging focuses on understanding the brain mechanisms of pain and neuroinflammation in humans. Last year, Loggia and his colleagues showed in another study that fibromyalgia patients have extensive neuroinflammation. “So, we asked, Do veterans who have Gulf War Illness demonstrate evidence of neuroinflammation, too?”

To find out, Loggia and his team collaborated with the Gulf War Illness Consortium at Boston University, which helped them to recruit Gulf War veterans. The study included 23 veterans, of whom 15 had GWI, as well as 25 healthy civilian subjects. All study participants’ brains were scanned using positron-emission tomography (PET) imaging, which measured levels of a molecule called translocator protein that rises in the presence of neuroinflammation. The scans detected little evidence of neuroinflammation in the healthy controls and veterans who were free of GWI. By contrast, the study found extensive inflammation in the brains of veterans with GWI, “particularly in the cortical regions, which are involved in ‘higher-order’ functions, such as memory, concentration and reasoning,” says Zeynab Alshelh, PhD, one of two research fellows in Loggia’s lab who co-led the study. “The neuroinflammation looked very similar to the widespread cortical inflammation we detected in fibromyalgia patients,” says Alshelh.

What might cause neuroinflammation? The central nervous system has legions of immune cells that protect the brain by detecting bacteria, viruses, and other potentially harmful agents, then producing inflammatory molecules to destroy the invaders, explains Loggia. However, while this response can be beneficial in the short term, it may become exaggerated, says Loggia, “and when that happens, inflammation becomes pathological — it becomes the problem.”

Research by Loggia’s lab and other investigators has also implicated neuroinflammation in a number of additional conditions, including chronic pain, depression, anxiety, autism, amyotrophic lateral sclerosis (ALS), multiple sclerosis (MS), Huntington’s disease and migraine. The findings of the GWI study, says Loggia, “could help motivate a more aggressive evaluation of neuroinflammation as a potential therapeutic target.”

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Materials provided by Massachusetts General Hospital. Note: Content may be edited for style and length.