Environmental DNA uncovers a 2-million-year-old ecosystem in Greenland

Reconstruction of the Kap København formation two-million years ago, in a time where the temperature was significantly warmer than northernmost Greenland today.
Illustration Credit: Beth Zaiken.

Scientific Frontline: "At a Glance" Summary

• Main Discovery: Researchers recovered the oldest environmental DNA (eDNA) on record, unveiling a 2-million-year-old ecosystem in northern Greenland populated by mastodons, reindeer, and poplar trees.
• Methodology: The team employed shotgun sequencing on sediment samples from the Kap København Formation and utilized beryllium and aluminum isotope analysis to precisely date the geologic layers.
• Key Data: The biological material dates back 2 million years, originating from a period when annual temperatures were 11 to 19 degrees Celsius higher than current values, and yielded five times as many plant varieties as previous ancient sediment studies.
• Significance: This discovery confirms that a highly diverse boreal forest community, including large mammals, thrived in what is now a polar desert, creating a biological composition with no modern analogue.
• Future Application: These findings provide a critical baseline for predicting long-term ecological shifts due to modern global warming and suggest that detailed genetic records may survive in other high-Arctic localities.
• Branch of Science: Paleoclimatology and Ancient Genomics.
• Additional Detail: The detection of mastodon DNA marks the first evidence of these extinct proboscideans ranging as far north as Greenland, significantly expanding their known paleogeographic distribution.

Mekong Delta will continue to be at risk for severe flooding

Mekong River Delta
Photo Credit: Tsuyoshi Watanabe

Reef corals provide an accurate, high-resolution record of the influence of the El Niño Southern Oscillation on rainfall, flooding and droughts in the Mekong River Delta, Vietnam.

The Mekong River Delta is the agricultural heartland of Vietnam; it is affected by droughts and flooding, which have become more severe in recent years. If severe weather events can be more accurately predicted, risk assessments in the regions can be improved. This, in turn, will reduce the negative effects of floods and droughts in the region.

A team led by Tsuyoshi Watanabe at Hokkaido University has revealed the clearest picture yet of how the El Niño Southern Oscillation (ENSO) affected rainfall in the Mekong Delta over the last hundred years. Their findings were published in the journal Scientific Reports. They correlated water salinity data from reef coral samples with historical weather records and uncovered that the ENSO has caused seasons of heavy and light rainfall, resulting in patterns of both flooding and droughts, respectively.

The ENSO occurs in the central and Eastern tropical Pacific Ocean, in irregular cycles of two to seven years. It consists of the El Niño (warming of the ocean surface), La Niña (cooling of the ocean surface) and neutral (neither warming, nor cooling).

Common medicine can stop the transmission of HIV infection from mother to child

The risk of transmission of HIV infection from mother to child has been reduced in resource-poor countries.
Photo Credit: Antony Trivet

Antiviral drugs almost completely reduce the risk of mothers passing on HIV infection to their children, even in a low-income country with a high HIV incidence such as Tanzania, according to a new study in The Lancet HIV by researchers from Karolinska Institutet. The discovery raises hopes of achieving the World Health Organization’s goal of eliminating the spread of infection from mother to child.

Only 159 infants were infected

The women were followed for 18 months after giving birth when most of them had stopped breastfeeding. When the researchers examined the mothers’ children, they discovered that only 159 of the more than 13,000 infants had been infected with HIV by the age of 1.5 years. Taking into account the margin of error, this means a risk of 1.4 per cent.

Wearable sensor could guide precision drug dosing

 The sensor uses microneedles that are made by cutting down clinical-grade acupuncture needles.
Image Credit: Emaminejad Lab/UCLA

For some of the powerful drugs used to fight infection and cancer, there’s only a small difference between a healing dose and a dose that’s large enough to cause dangerous side effects. But predicting that margin is a persistent challenge because different people react differently to medications — even to the same dose.

Currently, doctors can calibrate the amount of medication they administer in part by drawing blood to test the amount of medicine in a patient’s body. But results from those tests often take a day to process and only measure dosage at one or two moments in time, so they don’t help much when determining how to adjust dosage amounts in real time.

Now, a UCLA-led research team has developed a wearable patch that uses inexpensive microneedles to analyze the fluid between cells less than a millimeter underneath the skin and continuously record concentrations of medicine in the body. The technology could be a step toward improving doctors’ ability to administer precise medication doses.

In a study published in Science Advances, the investigators tested the system in rats that had been treated with antibiotics. Using data taken by the device within about 15 minutes after the medication was administered, the researchers reliably forecast how much of that drug would be effectively delivered to the animal’s system in total.

Brookhaven Lab to Lead New 'Saturated Glue' Theory Collaboration

Gluons at the Speed of Light
Gluons are always popping in and out of existence like blinking fireflies. But when nuclei or protons are accelerated to high energies, the gluons inside appear to multiply. That's because time operates in weird ways near the speed of light. The "blinking" appears to slow down, which makes the gluons linger longer. Energetic particle collisions can help physicists study this gluon-dominated state and, guided by new approaches to nuclear theory, search for signs of gluon saturation.
Illustration Credit: Brookhaven National Laboratory

The U.S. Department of Energy (DOE) has announced funding for a new Topical Theory Collaboration to be led by DOE’s Brookhaven National Laboratory that will aid in the discovery and exploration of a saturated state of gluons. These aptly named particles carry the nuclear strong force, acting as the ‘glue’ that holds together quarks, the building blocks of all visible matter. By understanding gluons’ ability to split and recombine and potentially reach a state of saturation, scientists hope to gain deeper insight into the strong force and the role gluons play in generating the mass, spin, and other properties of hadrons—composite particles made of quarks, such as the protons and neutrons of atomic nuclei.

The SatURated GluE (SURGE) Topical Theory Collaboration aims to develop calculations and a theoretical framework for discovering this unique saturated form of gluonic matter. Such a saturated state is predicted by the theory of quantum chromodynamics (QCD) to be observable in particles accelerated to high energies in particle colliders such as the Relativistic Heavy Ion Collider (RHIC) at Brookhaven Lab, the Large Hadron Collider (LHC) at Europe’s CERN laboratory, and the future Electron-Ion Collider (EIC) at Brookhaven.

Using light to manipulate neuron excitability

MIT and Harvard University researchers have devised a way to achieve long-term changes in neuron activity. With their new strategy, they can use light exposure to change the electrical capacitance of the neurons’ membranes, which alters their excitability (how strongly or weakly they respond to electrical signals).
Photo Credit: SFLORG stock image

Nearly 20 years ago, scientists developed ways to stimulate or silence neurons by shining light on them. This technique, known as optogenetics, allows researchers to discover the functions of specific neurons and how they communicate with other neurons to form circuits.

Building on that technique, MIT and Harvard University researchers have now devised a way to achieve longer-term changes in neuron activity. With their new strategy, they can use light exposure to change the electrical capacitance of the neurons’ membranes, which alters their excitability (how strongly or weakly they respond to electrical and physiological signals).

Changes in neuron excitability have been linked to many processes in the brain, including learning and aging, and have also been observed in some brain disorders, including Alzheimer’s disease.

“This new tool is designed to tune neuron excitability up and down in a light-controllable and long-term manner, which will enable scientists to directly establish the causality between the excitability of various neuron types and animal behaviors,” says Xiao Wang, the Thomas D. and Virginia Cabot Assistant Professor of Chemistry at MIT, and a member of the Broad Institute of MIT and Harvard. “Future application of our approach in disease models will tell whether fine-tuning neuron excitability could help reset abnormal brain circuits to normal.”

Jawbone may represent earliest presence of humans in Europe

For over a century, one of the earliest human fossils ever discovered in Spain has been long considered a Neandertal. However, new analysis from an international research team, including scientists at Binghamton University, State University of New York, dismantles this century-long interpretation, demonstrating that this fossil is not a Neandertal; rather, it may actually represent the earliest presence of Homo sapiens ever documented in Europe.

In 1887, a fossil mandible was discovered during quarrying activities in the town of Banyoles, Spain, and has been studied by different researchers over the past century. The Banyoles fossil likely dates to between approximately 45,000-65,000 years ago, at a time when Europe was occupied by Neandertals, and most researchers have generally linked it to this species.

“The mandible has been studied throughout the past century and was long considered to be a Neandertal based on its age and location, and the fact that it lacks one of the diagnostic features of Homo sapiens: a chin,” said Binghamton University graduate student Brian Keeling.

The new study relied on virtual techniques, including CT scanning of the original fossil. This was used to virtually reconstruct missing parts of the fossil, and then to generate a 3D model to be analyzed on the computer.

Many genes linked to alcohol and tobacco use are shared among diverse ancestries

Penn State College of Medicine researchers co-led a large genetic study that identified more than 2,300 genes predicting alcohol and tobacco use. They said that many of these genes were similar among people with diverse ancestries.
Photo Credit: Pavel Danilyuk

Penn State researchers co-led a large genetic study that identified more than 2,300 genes predicting alcohol and tobacco use after analyzing data from more than 3.4 million people. They said a majority of these genes were similar among people with European, African, American and Asian ancestries.

Alcohol and tobacco use are associated with approximately 15% and 5% of deaths worldwide, respectively, and are linked with chronic conditions like cancer and heart disease. Although the environment and culture can affect a person’s use and the likelihood of becoming addicted to these substances, genetics is also a contributing factor, according to Penn State College of Medicine researchers. They helped identify around 400 genes that are associated with certain alcohol and tobacco use behaviors in people in a prior research study.

“We’ve now identified more than 1,900 additional genes that are associated with alcohol and tobacco use behaviors,” said Dajiang Liu, professor and vice chair for research in the Department of Public Health Sciences. “A fifth of the samples used in our analysis were from non-European ancestries, which increases the relevance of these findings to a diverse population.”

It’s colossal: Creating the world’s largest dilution refrigerator

Colossus will offer 5 cubic meters of space and cool components to around 0.01K.
Photo Credit: Ryan Postel, Fermilab

While the refrigerator in your kitchen gets cold enough to prevent your leftovers from spoiling, dilution refrigerators used for quantum computing research cool devices near the coldest physical temperature possible. Now at the U.S. Department of Energy’s Fermi National Accelerator Laboratory, researchers are building Colossus: It will be the largest, most powerful refrigerator at millikelvin temperatures ever created.

Fermilab is known for its massive experiments, and Colossus will fit right in. Researchers from the Fermilab-hosted Superconducting Quantum Materials and Systems Center need lots of room at cold temperatures to achieve their goal of building a state-of-the-art quantum computer.

Unlike a kitchen refrigerator, which compresses gases called refrigerants to cool food, a dilution refrigerator uses a mixture of helium isotopes to create temperatures close to absolute zero, or zero kelvin: the coldest temperature imaginable in physics, which is physically impossible to reach.

“With the cooling power and volume that Colossus will provide, SQMS researchers will have unprecedented space for our future quantum computer and many other quantum computing and physics experiments,” said Matt Hollister, the lead technical expert on this project. “Colossus is named after the first electronic programmable computer, which was constructed in the 1940s for codebreaking. It was a historic milestone in the history of computing and seemed like an appropriate name for the size of our new refrigerator.”

New branch on tree of life includes ‘lions of the microbial world’

On the left is a starving provoran. On the right, it has engulfed its prey.
Photo Credit: Tikhonenkov, Mikhailov, Gawryluk, Belyaev, Mathur, Karpov, Zagumyonnyi, Borodina, Prokina, Mylnikov, Aleoshin, and Keeling, Nature

There’s a new branch on the tree of life and it’s made up of predators that nibble their prey to death.

These microbial predators fall into two groups, one of which researchers have dubbed “nibblerids” because they, well, nibble chunks off their prey using tooth-like structures. The other group, nebulids, eat their prey whole. And both comprise a new ancient branch on the tree of life called “Provora,” according to a paper published today in the journal Nature.

Microbial lions

Like lions, cheetahs, and more familiar predators, these microbes are numerically rare but important to the ecosystem, says senior author Dr. Patrick Keeling, professor in the UBC department of botany. “Imagine if you were an alien and sampled the Serengeti: you would get a lot of plants and maybe a gazelle, but no lions. But lions do matter, even if they are rare. These are lions of the microbial world.”

Using water samples from marine habitats around the world, including the coral reefs of Curaçao, sediment from the Black and Red seas, and water from the northeast Pacific and Arctic oceans, the researchers discovered new microbes. “I noticed that in some water samples there were tiny organisms with two flagella, or tails, that convulsively spun in place or swam very quickly. Thus began my hunt for these microbes,” said first author Dr. Denis Tikhonenkov, senior researcher at the Institute for Biology of Inland Waters of the Russian Academy of Sciences.