Small eddies play a big role in feeding ocean microbes

This video still of the North Pacific Ocean shows phosphate nutrient concentrations at 500 meters below the ocean surface. The swirls represent small eddies transporting phosphate from the nutrient-rich equator (lighter colors), northward toward the nutrient-depleted subtropics (darker colors).
Credit: Courtesy of the researchers

Subtropical gyres are enormous rotating ocean currents that generate sustained circulations in the Earth’s subtropical regions just to the north and south of the equator. These gyres are slow-moving whirlpools that circulate within massive basins around the world, gathering up nutrients, organisms, and sometimes trash, as the currents rotate from coast to coast.

For years, oceanographers have puzzled over conflicting observations within subtropical gyres. At the surface, these massive currents appear to host healthy populations of phytoplankton — microbes that feed the rest of the ocean food chain and are responsible for sucking up a significant portion of the atmosphere’s carbon dioxide.

But judging from what scientists know about the dynamics of gyres, they estimated the currents themselves wouldn’t be able to maintain enough nutrients to sustain the phytoplankton they were seeing. How, then, were the microbes able to thrive?

Now, MIT researchers have found that phytoplankton may receive deliveries of nutrients from outside the gyres, and that the delivery vehicle is in the form of eddies — much smaller currents that swirl at the edges of a gyre. These eddies pull nutrients in from high-nutrient equatorial regions and push them into the center of a gyre, where the nutrients are then taken up by other currents and pumped to the surface to feed phytoplankton.

La Niña winters could keep on coming

In the Pacific Northwest, La Niña winters tend to be colder and wetter than average. The past two winters have fit that description, including this February 2021 snowfall in Seattle’s Volunteer Park. Credit: Seattle Parks and Recreation/Flickr

Forecasters are predicting a “three-peat La Niña” this year. This will be the third winter in a row that the Pacific Ocean has been in a La Niña cycle, something that’s happened only twice before in records going back to 1950.

New research led by the University of Washington offers a possible explanation. The study, recently published in Geophysical Research Letters, suggests that climate change is, in the short term, favoring La Niñas.

“The Pacific Ocean naturally cycles between El Niño and La Niña conditions, but our work suggests that climate change could currently be weighing the dice toward La Niña,” said lead author Robert Jnglin Wills, a UW research scientist in atmospheric sciences. “At some point, we expect anthropogenic, or human-caused, influences to reverse these trends and give El Niño the upper hand.”

Scientists hope to predict the direction of these longer-term El Niño-like or La Niña-like climate trends in order to protect human life and property.

“This is an important question over the next century for regions that are strongly influenced by El Niño, which includes western North America, South America, East and Southeast Asia and Australia,” Wills said.

Specialized smart soft contact lenses can address global issues of glaucoma diagnosis and management

New smart soft contact lens technology developed by a multidisciplinary team of engineers and health care researchers at Purdue University and Indiana University School of Optometry looks to gather important intraocular pressure measurements for 24-hour cycles as a way to detect glaucoma.
Credit: Purdue University photo/Rebecca McElhoe

The vision of Purdue University biomedical engineer Chi Hwan Lee to develop specialized smart soft contact lenses that can accurately measure intraocular pressure (IOP) in a person’s eye could be the latest answer to stopping glaucoma-related blindness.

Lee, the Leslie A. Geddes Associate Professor of Biomedical Engineering in Purdue’s Weldon School of Biomedical Engineering, led a research team that developed new ocular technology to continuously monitor patients’ IOP readings more comfortably and accurately.

The technology serves as another option for eye specialists to identify glaucoma, which, according to the Glaucoma Research Foundation, can steal a person’s vision without early warning signs or pain and affects more than 80 million people worldwide.

The only known modifiable risk factor is lowering a person’s IOP, which is difficult to monitor for long periods of time, particularly during sleep.

While exams can be performed in a specialist’s office and at-home monitoring systems are available, these all have their limitations. For instance, in-office measures are time-consuming, and current at-home technology is difficult to use, is uncomfortable and doesn’t gather sufficient data at the right time periods or over long enough time periods for specialists to appropriately use the information to make optimized treatment decisions.

Not enough: Protecting algae-eating fish insufficient to save imperiled coral reefs

Bright blue Chromis fish on acropora coral at a back reef on the French Polynesian island of Mo’orea.
 Image credit: Kelly Speare

How can we boost the resilience of the world’s coral reefs, which are imperiled by multiple stresses including mass bleaching events linked to climate warming?

One strategy advocated by some researchers, resource managers and conservationists is to restore populations of algae-eating reef fish, such as parrotfish. Protecting the fish that keep algae in check leads to healthier corals and can promote the recovery of distressed reefs, according to this idea, which is known as fish-mediated resilience.

But a new study that analyzed long-term data from 57 coral reefs around the French Polynesian island of Mo’orea challenges this canon of coral reef ecology.

The study, published online Oct. 3 in the journal Nature Ecology & Evolution, provides compelling new evidence that fish don’t regulate coral over time, according to University of Michigan marine ecologist and study co-senior author Jacob Allgeier. The other author is former U-M postdoctoral researcher Timothy Cline.

North Carolina Lake Sediments Show Decades of Coal Ash Contamination

Bottom sediments from five North Carolina lakes near coal-fired power plants shows coal ash contamination that likely entered the lakes by three different routes.
Credit: Avner Vengosh

An analysis of sediments from five North Carolina lakes near coal-burning power plants has found that coal ash pollution of surface waters has been more persistent and widespread than was previously known.

The findings, from scientists at Duke University and Appalachian State University, show that large quantities of coal ash have been transferred and deposited in lake sediments since the beginning of coal operations in North Carolina.

“The bottom sediments of a lake represent a complete history of what has fallen into the lake water and settled to the bottom,” said Avner Vengosh, a Duke University Distinguished Professor of Environmental Quality at the Nicholas School of the Environment. “Using our age-dating methods, we were able to go back in time, in some cases even before the coal plant was built, and reconstruct the history of the lakes.”

Coal ash is the residual material from burning coal to generate electricity, and is known to contain hazardous metals including lead, chromium, cadmium, mercury, arsenic, selenium and molybdenum, many of which have been tied to human cancers and other health effects.

AI boosts usability of paper-making waste products

Photo and graphic with birch tree by J. Löfgren

In a new and exciting collaboration with the Department of Bioproducts and Biosystems, researchers in the CEST group have published a study demonstrating how artificial intelligence (AI) can boost the production of renewable biomaterials. Their publication focuses on the extraction of lignin, an organic polymer that together with cellulose makes up the cell walls of plants. As a side-product of papermaking, lignin is produced in large quantities around the world but seldom used as anything other than cheap fuel. Developing valuable materials and chemicals from lignin would consequently be a big step towards a sustainable society.

A key challenge for the valorization of lignin is to find the right experimental extraction conditions. These include things like the temperature in the hot-water reactor where the wood is processed, the reaction time and the ratio of wood to water. These conditions not only affect the amount of lignin that can be extracted, but also the physical and chemical properties of the extracted lignin itself. Therefore, knowing how to choose the right experimental conditions is important since the more lignin can be extracted the better, and different lignin-based products may require lignin with different properties.

U.S. Army Orders Additional Enhanced CH-47F Block II Chinooks

The CH-47F Block II during first flight. The Block II Chinook is powered by cutting-edge technologies — including redesigned fuel tanks, a strengthened fuselage and an enhanced drivetrain.
Resized Image using AI by SFLORG
Photo Credit: Fred Troilo

The U.S. Army is continuing to modernize its heavy-lift helicopter fleet with an order for two more Boeing CH-47F Block II Chinooks and long lead funding for additional aircraft.

“Modernizing the Chinook for our Army customer is a priority,” said Ken Eland, Boeing vice president and H-47 program manager. “CH-47F Block II improves readiness, limits future sustainment costs and provides commonality across the fleet. We're dedicated to making CH-47F Block II the best option for the Army's heavy lift mission, now and well into the future." The CH-47F Block II Chinook is powered by cutting-edge technologies — including redesigned fuel tanks, a strengthened fuselage and an enhanced drivetrain.

Last year, the Army awarded Boeing a $136 million contract for the first four CH-47F Block II aircraft, which began production in April 2022. The Lot 2 order valued at $63 million brings the total number of aircraft under contract to six. The separate Lot 3 advance procurement contract is valued at $29 million

Jurassic ichthyosaurs divided food resources to co-exist, researchers find

The skull of Ichthyosaurs Hauffiopteryx typicus from the Strawberry Bank Lagerstätt, one of the specimens that were the subject of this study.
Credit: Bath Royal Literary and Scientific Institution Collections

Early Jurassic ichthyosaur juveniles show predatory specializations, scientists at the University of Bristol have revealed.

Their findings, published today in Journal of Anatomy, suggest that physical differences in their snouts show they evolved to have different diets and were not competing for the same resource.

Ichthyosaurs, the classic ‘sea dragons’, were dolphin-shaped marine predators that fed on fish and squid-like swimming shellfish. The ichthyosaurs of the Lower Jurassic, some 185 million years ago, are renowned because the first specimens were found over 200 years ago at Lyme Regis in southern England, by the celebrated fossil collector and paleontologist Mary Anning. Some of her specimens have long, slender snouts and others have short, broad snouts.

“Functional studies need excellent three-dimensional specimens,” said Matt Williams of Bath Royal Literary and Scientific Institution, “and the Lower Jurassic ichthyosaur fossils from Strawberry Bank in Ilminster are just that. Mary Anning’s fossils are amazing, but they are mostly squashed flat.”

Exploring Europa Possible with Silicon-Germanium Transistor Technology

Europa Image
Credit: NASA/JPL-Caltech/SETI Institute

Europa is more than just one of Jupiter’s many moons – it’s also one of most promising places in the solar system to look for extraterrestrial life. Under 10 kilometers of ice is a liquid water ocean that could sustain life. But with surface temperatures at -180 Celsius and with extreme levels of radiation, it’s also one of the most inhospitable places in the solar system. Exploring Europa could be possible in the coming years thanks to new applications for silicon-germanium transistor technology research at Georgia Tech.

Regents’ Professor John D. Cressler in the School of Electrical and Computer Engineering (ECE) and his students have been working with silicon-germanium heterojunction bipolar transistors (SiGe HBTs) for decades and have found them to have unique advantages in extreme environments like Europa.

“Due to the way that they're made, these devices actually survive those extreme conditions without any changes made to the underlying technology itself,” said Cressler, who is the project investigator. “You can build it for what you want it to do on Earth, and you then can use it in space.”

The researchers are in year one of a three-year grant in the NASA Concepts for Ocean Worlds Life Detection Technology (COLDTech) program to design the electronics infrastructure for upcoming Europa surface missions. NASA plans to launch the Europa Clipper in 2024, an orbiting spacecraft that will map the oceans of Europa, and then eventually send a landing vehicle, Europa Lander, to drill through the ice and explore its ocean. But it all starts with electronics that can function in Europa’s extreme environment.

Cressler and his students, together with researchers from NASA Jet Propulsion Lab (JPL) and the University of Tennessee (UT), demonstrated the capabilities of SiGe HBTs for this hostile environment in a paper presented at the IEEE Nuclear and Space Radiation Effects Conference in July.

What caused the holes in SUE the T. rex ’s jaw? Probably not an infection

Field Museum paleontologist Jingmai O’Connor with SUE the T. rex’s skull.
Resized Image using AI by SFLORG
Credit: Katharine Uhrich, Field Museum

SUE the T. rex is one of the most complete, best-preserved Tyrannosaurus rex specimens ever found. That level of preservation helps reveal details about SUE’s life. For instance, SUE lived to a ripe old age of about thirty-three, and in those years, suffered their fair share of injuries. SUE’s most mysterious ailment might be the holes in their jawbone. These holes, some the diameter of a golf ball, dot the back half of the left lower jaw. It’s not clear what caused them, but similar injuries have been found in other T. rex fossils. In a new study published in Cretaceous Research, scientists showed that one of the popular theories-- that SUE had suffered an infection from a protozoan parasite-- couldn’t be true.

“These holes in SUE’s jaw have been a mystery for decades,” says Jingmai O’Connor, the associate curator of fossil reptiles at Chicago’s Field Museum and a co-author of the study. “Nobody knows how they formed, and there have been lots of guesses.”

One early hypothesis was that SUE suffered from a fungus-like bacterial infection, but that was later shown to be unlikely. It was re-hypothesized that SUE had a protozoan infection. Protozoans are microbes with more complex cell structures than bacteria. There are lots of protozoan-caused maladies out there; one common such disease is called trichomoniasis, caused by a microbe called Trichomonas vaginalis. Humans can get infected with trichomoniasis as an STD, but other animals can catch it too.