Pinpointing HIV immune response

HIV, the AIDS virus (yellow), infecting a human cell
Image Credit: National Cancer Institute

New research combining computer modeling and experiments with macaques shows the body’s immune system helps control human immunodeficiency virus (HIV) infections largely by suppressing viral production in already infected cells while also killing viral infected cells, but only within a narrow time window at the start of a cell’s infection.

“To eliminate HIV, we have to understand how the immune system attempts to control the infection,” said Ruy M. Ribeiro, a theoretical biologist at Los Alamos National Laboratory who led the development of the model underpinning the research. Ribeiro is the corresponding author of the paper about the findings, published in Nature Communications.

The research team included Los Alamos Senior Fellow Alan S. Perelson and a former Los Alamos postdoctoral researcher now at the Fred Hutchinson Cancer Research Center. Their collaborators at the University of Pittsburg managed the experiments with macaques infected with simian immunodeficiency virus (SIV) to validate the model. SIV infections in monkeys behave the same way as HIV in humans.

Giant planets cast a deadly pall

Artist's depiction of a star system that is crowded with giant planets.
Illustration Credit: NASA/Dana Berry

Giant gas planets can be agents of chaos, ensuring nothing lives on their Earth-like neighbors around other stars. New studies show, in some planetary systems, the giants tend to kick smaller planets out of orbit and wreak havoc on their climates. 

Jupiter, by far the biggest planet in our solar system, plays an important protective role. Its enormous gravitational field deflects comets and asteroids that might otherwise hit Earth, helping create a stable environment for life. However, giant planets elsewhere in the universe do not necessarily protect life on their smaller, rocky planet neighbors. 

A new Astronomical Journal paper details how the pull of massive planets in a nearby star system are likely to toss their Earth-like neighbors out of the “habitable zone.” This zone is defined as the range of distances from a star that is warm enough for liquid water to exist on a planet’s surface, making life possible.

Unlike most other known solar systems, the four giant planets in HD 141399 are farther from their star. This makes it a good model for comparison with our solar system where Jupiter and Saturn are also relatively far from the sun.  

“It’s as if they have four Jupiters acting like wrecking balls, throwing everything out of whack,” said Stephen Kane, UC Riverside astrophysicist and author of the journal paper. 

Researchers observe wolves hunting and killing sea otters and harbor seals on Alaska’s Katmai coast

Wolf with a sea otter on Alaska's Katmai coast.
Photo Credit: Kelsey Griffin

Firsthand observations of a wolf hunting and killing a harbor seal and a group of wolves hunting and consuming a sea otter on Alaska’s Katmai coast have led scientists to reconsider assumptions about wolf hunting behavior.

Wolves have previously been observed consuming sea otter carcasses, but how they obtain these and the frequency of scavenging versus hunting marine prey is largely unknown. Scientists at Oregon State University, the National Park Service and Alaska Department of Fish and Game are beginning to change that with a paper just published in Ecology.

In the paper, they describe several incidents they observed involving wolves and marine mammals in Katmai National Park that they believe haven’t been previously documented:

The importance of the Earth's atmosphere in creating the large storms that affect satellite communications

Illustration Credit: ERG Science Team

A study from an international team led by researchers from Nagoya University in Japan and the University of New Hampshire in the United States has revealed the importance of the Earth’s upper atmosphere in determining how large geomagnetic storms develop. Their findings reveal the previously underestimated importance of the Earth’s atmosphere. Understanding the factors that cause geomagnetic storms is important because they can have a direct impact on the Earth’s magnetic field such as causing unwanted currents in the power grid and disrupting radio signals and GPS. This research may help predict the storms that will have the greatest consequences. 

Scientists have long known that geomagnetic storms are associated with the activities of the Sun. Hot charged particles make up the Sun's outer layer, the one visible to us. These particles flow out of the Sun creating the ‘solar wind’, and interact with objects in space, such as the Earth. When the particles reach the magnetic field surrounding our planet, known as the magnetosphere, they interact with it. The interactions between the charged particles and magnetic fields lead to space weather, the conditions in space that can affect the Earth and technological systems such as satellites.  

Window to avoid 1.5°C of warming rapidly closing

Photo Credit: Patrick Hendry / altered by Scientific Frontline

Humanity is rapidly reaching the limit for how much additional carbon can be emitted into the atmosphere to keep global warming within 1.5 °C, according to new research.

If emissions stay at current day levels, what is known as the "remaining carbon budget" will be exhausted before the end of the decade. 

Dr Chris Smith, climate modeler and a research fellow in the School of Earth and Environment at Leeds, co-authored the study.  He said: “This study gives the most updated measure of how much more carbon dioxide humanity can continue to put into the atmosphere to give us a fifty per cent chance of staying within the 1.5 °C threshold agreed at international climate talks.  

"If we continue to emit carbon dioxide at current levels, we will exhaust that remaining 1.5°C carbon budget in just six years.   

“This is not to say that we only have ‘six years to save the planet’, because 1.5°C is not a hard boundary of when climate change will suddenly become much worse. However, damages, risks and the likelihood of exceeding physical and ecological tipping points increase sharply with continued warming.  

Study Suggests Epigenetic Age May Predict Memory Function Better Than Actual Age

The Stony Brook research team investigating epigenetic age acceleration hope to understand more about the biological and environmental factors related to it. From left: Daisy V. Zavala, Stacey Scott and Krishna Veeramah.
Photo Credit: John Griffin, Stony Brook University

A study led by researchers at Stony Brook University shows that age acceleration, when one’s so-called biological clock runs quicker than one’s actual age, is linked to poorer memory and slower rates of processing information. The team measured biological “clocks” derived from the DNA of 142 adults aged 25-65 years old and had the participants complete daily cognitive tests on smartphones. Their findings, which imply that epigenetic age acceleration could be a better indicator of how well a person remembers information and how quickly they work with information, are detailed in the Journal of Gerontology: Biological Sciences.

There are well-known chronological age differences in cognitive performance — on average, younger adults tend to remember more information and respond more quickly than older adults. One presumed explanation is biological wear-and-tear across life, but until recently, there was not a way to test biological aging to explain these differences between younger and older people.

Aging researchers currently have significant interest in examining epigenetic patterns that change how the DNA in our cells fold and how genes behave. Unlike our DNA genome, which stays the same throughout our lifetime in every cell of our body, our epigenome can change through time and can be influenced by our behavior and environment. These epigenetic changes can thus indicate a person’s biological age, which may differ from chronological age.

To advance space colonization, WVU research explores 3D printing in microgravity

WVU engineering students and Microgravity Research Team members Renee Garneau, Trenton Morris and Ronan Butts test a 3D printer the MRT lab has designed to operate in weightless environments like a spaceship, the moon or Mars.
Photo Credit: Brian Persinger / West Virginia University

Research from West Virginia University students and faculty into how 3D printing works in a weightless environment aims to support long-term exploration and habitation on spaceships, the moon or Mars.

Extended missions in outer space require the manufacture of crucial materials and equipment onsite, rather than transporting those items from Earth. Members of the Microgravity Research Team said they believe 3D printing is the way to make that happen.

The team’s recent experiments focused on how a weightless microgravity environment affects 3D printing using titania foam, a material with potential applications ranging from UV blocking to water purification. ACS Applied Materials and Interfaces published their findings.

“A spacecraft can’t carry infinite resources, so you have to maintain and recycle what you have and 3D printing enables that,” said lead author Jacob Cordonier, a doctoral student in mechanical and aerospace engineering at the WVU Benjamin M. Statler College of Engineering and Mineral Resources. “You can print only what you need, reducing waste. Our study looked at whether a 3D-printed titanium dioxide foam could protect against ultraviolet radiation in outer space and purify water. 

New Frequency Comb Can Identify Molecules in 20-Nanosecond Snapshots

A new frequency comb setup can capture the moment-by-moment details of carbon dioxide gas escaping from a nozzle at supersonic speeds in an air-filled chamber, followed by rapid oscillations of gas due to complex aerodynamics within the chamber. The data plot shows the absorbance of light (vertical) over time (horizontal left to right) across a range of frequencies (horizontal forward to back).
Illustration Credit: G. Mathews/University of Colorado Boulder

From monitoring concentrations of greenhouse gases to detecting COVID in the breath, laser systems known as frequency combs can identify specific molecules as simple as carbon dioxide and as complex as monoclonal antibodies with unprecedented accuracy and sensitivity. Amazing as they are, however, frequency combs have been limited in how fast they can capture a high-speed process such as hypersonic propulsion or the folding of proteins into their final three-dimensional shapes.

Now, researchers at the National Institute of Standards and Technology (NIST), Toptica Photonics AG and the University of Colorado Boulder have developed a frequency comb system that can detect the presence of specific molecules in a sample every 20 nanoseconds, or billionths of a second. With this new capability, researchers can potentially use frequency combs to better understand the split-second intermediate steps in fast-moving processes ranging from the workings of hypersonic jet engines to the chemical reactions between enzymes that regulate cell growth. The research team announced its results in a paper published in Nature Photonics.

Bowel cancer: aspirin activates protective genes

Photo Credit: günter

Colorectal cancer (bowel cancer) is the third most common form of cancer worldwide, with around 1.9 million newly diagnosed cases and 900,000 deaths every year. Therefore, preventive substances represent an urgent clinical need. Aspirin/acetylsalicylic acid has proven to be one of the most promising candidates for the prevention of colorectal cancer. Among other findings, studies have shown that when patients with cardiovascular diseases took low doses of aspirin over several years, it reduced their risk of colorectal cancer. Furthermore, aspirin can inhibit the progression of colorectal cancer. Now a team led by Heiko Hermeking, Professor of Experimental and Molecular Pathology at LMU, has investigated which molecular mechanisms mediate these effects.

As the researchers report in the journal Cell Death and Disease, aspirin induces the production of two tumor-suppressive microRNA molecules (miRNAs) called miR-34a and miR-34b/c. To do this, aspirin binds to and activates the enzyme AMPK, which in turn alters the transcription factor NRF2 such that it migrates into the cell nucleus and activates the expression of the miR-34 genes. For this activation to succeed, aspirin additionally suppresses the oncogene product c-MYC, which otherwise inhibits NRF2.

New strategies needed to help banana farmers recover from climate shocks

Photo Credit: Jonas Von Werne

Extreme weather events and the globalized nature of food production puts smallholder farmers at risk of ‘double exposure’ of production and market loss, according to a new study.

Researchers including from the University of Exeter, University of Oxford and ETH Zurich, examined the Global Food Value Chain (GFVC) – an international network of stakeholders involved in food production, processing, distribution, retailing and consumption – of bananas grown in the Dominican Republic, the UK’s most important supplier of organic bananas.

They found that smallholder farmers hit by hurricane-induced flooding faced not only the loss of production but also a loss of market access for their undamaged produce, and called for new strategies to tackle the aftermath of climate shocks.

The researchers integrated satellite, household survey and trade data to investigate the impacts of two consecutive hurricanes (Hurricanes Irma and Maria in 2017) and subsequent flooding on smallholder banana farmers in Dominican Republic and what factors determined their recovery from such events.