Global study of hypoxia in rivers shows it is more prevalent than previously thought

High-frequency sensors deployed in streams, such as those being installed by Joanna Blaszczak in a stream in Montana, can provide continuous data that captures night-time hypoxic conditions.
Photo Credit: Malgosia Blaszczak.

New research led by University of Nevada, Reno Assistant Professor Joanna Blaszczak shows hypoxia in rivers and streams is generally much more prevalent across the globe than previously thought. Hypoxia is low or depleted oxygen levels in surface waters that can be harmful to aquatic species and can in some cases increase production of harmful greenhouse gases from rivers.

The research, published recently in the journal Limnology and Oceanography Letters, compiles over 118 million readings of dissolved oxygen and temperature taken from over 125,000 locations in rivers across six continents and 93 countries and spanning over 100 years, from 1900 to 2018. Hypoxia, defined in this study as dissolved oxygen concentrations below 2 milligrams per liter, was detected in rivers and streams in 53 countries, with 12.6% of all locations exhibiting at least one hypoxic measurement.

“Hypoxia in coastal waters and lakes is widely recognized as a detrimental environmental issue, yet we have lacked a comparable understanding of hypoxia in rivers,” Blaszczak, with the University’s College of Agriculture, Biotechnology & Natural Resources, said. “While 12.6% might not seem like a huge percentage, previously it was generally thought that occurrences of hypoxia in rivers and streams were exceedingly rare. Having shown presence of hypoxia in one of every eight river locations with data is definitely a game changer in terms of how we need to think of and give attention to the issue of hypoxia in rivers and streams.”

Lockheed Martin Announces Successful First Flight Of F-16 Block 70 Aircraft

F-16 Block 70 first flight
Photo Credit: Lockheed Martin Corporation

Lockheed Martin today announced the successful first flight of the F-16 Block 70 at its Greenville, South Carolina site. 

The flight occurred Jan. 24 at 9:17 a.m. ET, with Lockheed Martin test pilots Dwayne "Pro" Opella and Monessa "Siren" Balzhiser at the helm. Total flight time was approximately 50 minutes and included airworthiness checks, such as engine, flight control and fuel system checks, as well as basic aircraft handling. 

"Today's successful flight is a testament of the hard work, dedication and commitment to our customers and their missions," said OJ Sanchez, vice president, Integrated Fighter Group, which includes the F-16 program. "This milestone demonstrates Lockheed Martin's commitment to advancing this program and getting this much-needed aircraft and its advanced 21st Century Security capabilities to the warfighter."

This F-16 Block 70 jet is the first of 16 jets to be delivered to Bahrain. Six countries have selected Block 70/72 aircraft. In addition to the current official backlog of 128 jets to-date to be built in Greenville, Jordan last year signed a Letter of Offer and Acceptance (LOA) for eight jets and last week signed an additional LOA for four more jets. Lockheed Martin has received a contract to begin Jordan's long-lead activities. Bulgaria has also signed an LOA for an additional eight jets for its fleet. Once these are finalized, the backlog will increase to 148.

Plasma thrusters used on satellites could be much more powerful

The chamber where prof. Benjamin Jorns’ team tests the new Hall plasma thruster at the PEPL lab on the University of Michigan’s North Campus.
Photo Credit: Marcin Szczepanski/Lead Multimedia Storyteller, University of Michigan College of Engineering

It was believed that running more propellant through a Hall thruster would wreck its efficiency, but new experiments suggest they might power a crewed mission to Mars

It was believed that Hall thrusters, an efficient kind of electric propulsion widely used in orbit, need to be large to produce a lot of thrust. Now, a new study from the University of Michigan suggests that smaller Hall thrusters can generate much more thrust—potentially making them candidates for interplanetary missions.

“People had previously thought that you could only push a certain amount of current through a thruster area, which in turn translates directly into how much force or thrust you can generate per unit area,” said Benjamin Jorns, U-M associate professor of aerospace engineering who led the new Hall thruster study to be presented at the AIAA SciTech Forum in National Harbor, Maryland, today.

Environment law fails to protect threatened species

The tiger quoll lost 82 per cent of its total referred habitat to projects considered unlikely to have a significant impact.
Photo Credit: JJ Harrison / Creative Commons Attribution-Share Alike 3.0 Unported

Federal environmental laws are failing to mitigate against Australia’s extinction crisis, according to University of Queensland research.

UQ PhD candidate Natalya Maitz led a collaborative project which analyzed potential habitat loss in Queensland and New South Wales and found the Environment Protection and Biodiversity Conservation 1999 (EPBC) Act is not protecting threatened species.

“The system designed to classify development projects according to their environmental impact is more or less worthless,” Ms. Maitz said.

“There’s no statistically significant difference between the amount of threatened habitat destroyed under projects deemed ‘significant’ or ‘not significant’ by the national biodiversity regulator.”

Under the EPBC Act, individuals or organizations looking to commence projects with a potentially ‘significant impact’ on protected species must seek further federal review and approval.

Traffic pollution impairs brain function

fMRI shows decreased functional connectivity in the brain following exposure to traffic pollution.
Image Credit: Courtesy of University of British Columbia

First-in-the-world study suggests that even brief exposure to air pollution has rapid impacts on the brain

A new study by researchers at the University of British Columbia and the University of Victoria has shown that common levels of traffic pollution can impair human brain function in only a matter of hours.

The peer-reviewed findings, published in the journal Environmental Health, show that just two hours of exposure to diesel exhaust causes a decrease in the brain’s functional connectivity – a measure of how different areas of the brain interact and communicate with each other. The study provides the first evidence in humans, from a controlled experiment, of altered brain network connectivity induced by air pollution.

“For many decades, scientists thought the brain may be protected from the harmful effects of air pollution,” said senior study author Dr. Chris Carlsten, professor and head of respiratory medicine and the Canada Research Chair in occupational and environmental lung disease at UBC. “This study, which is the first of its kind in the world, provides fresh evidence supporting a connection between air pollution and cognition.”

Researchers combine classical and quantum optics for super-resolution imaging

A conceptual rendering of the super-resolution experiment, which will be enabled by a grant from the Chan Zuckerberg Initiative.
Illustration Credit: Courtesy of Colorado State University

The ability to see invisible structures in our bodies, like the inner workings of cells, or the aggregation of proteins, depends on the quality of one’s microscope. Ever since the first optical microscopes were invented in the 17th century, scientists have pushed for new ways to see things more clearly, at smaller scales and deeper depths.   

Randy Bartels, professor in the Department of Electrical Engineering at Colorado State University, is one of those scientists. He and a team of researchers at CSU and Colorado School of Mines are on a quest to invent some of the world’s most powerful light microscopes – ones that can resolve large swaths of biological material in unimaginable detail.   

The name of the game is super–resolution microscopy, which is any optical imaging technique that can resolve things smaller than half the wavelength of light. The discipline was the subject of the 2014 Nobel Prize in Chemistry, and Bartels and others are in a race to keep circumventing that diffraction limit to illuminate biologically important structures inside the body.  

New DNA Biosensor Could Unlock Powerful, Low-Cost Clinical Diagnostics

In a new study, researchers demonstrate the capability of DNA biosensor components for a unique modular DNA biosensor. The researchers plan to integrate their design within a device the size and shape of a smartphone for low-cost clinical diagnostics. 
Illustration Credit: N. Hanacek/NIST

DNA can signal the presence of or predisposition to a slew of diseases, including cancer. The ability to flag down these clues, known as biomarkers, allows medical professionals to make critical early diagnoses and provide personalized treatments. The typical methods of screening can be laborious, expensive or limited in what they can uncover. A new biosensor chip that boasts an accurate and inexpensive design may increase accessibility to high-quality diagnostics. 

The biosensor, developed by researchers at the National Institute of Standards and Technology (NIST), Brown University and the French government-funded research institute CEA-Leti, identifies biomarkers by measuring how binding occurs between DNA strands and the device. What sets it apart from other similar sensors is its modular design, which lowers costs by making it easier to mass produce and allowing the most expensive components to be reused. 

In a paper just posted online from the latest IEEE International Electron Devices Meeting, the researchers presented results of a study that demonstrates the device’s high sensitivity and precision despite its modularity, which is typically associated with diminished performance.

New enzyme could mean better drugs

A scientist works in the lab of Rice’s Xue Sherry Gao.
Photo Credit: Jeff Fitlow/Rice University

Just as a choreographer’s notation tells a dancer to strike a particular pose, an enzyme newly discovered by Rice University scientists is able to tell specific molecules precisely how to arrange themselves, down to the angle of single hydrogen bonds.

Biomolecular engineers at Rice identified a new Diels-Alderase (DAase), an enzyme that catalyzes the Diels-Alder reaction, a widely used method of synthesizing important materials and pharmaceuticals, from raw materials for plastics and fuels to synthetic steroids.

The enzyme, known as CtdP, was previously thought to be a different type of protein — a “regulator” controlling gene expression. Regulators typically do not serve a catalytic function, meaning they cannot “transform compound A into compound B,” said study co-author Xue Sherry Gao.

Mirror Image: FSU study lays out chirality flipping theory

Ken Hanson, left, and Eugene DePrince, right, are faculty members in the Department of Chemistry and Biochemistry.
Photo Credit: Florida State University

Chemists can make a career out of controlling whether certain molecules are generated as a lefty or a righty.

Molecules don’t literally have hands, but scientists often refer to them in this way when looking at molecules that are mirror images of each other and therefore are not superimposable. And whether a molecule is a lefty or a righty directly affects how they behave and their use in everything from drug design to flavoring foods.

A Florida State University research team led by Associate Professor of Chemistry Ken Hanson previously found a way to turn “left-handed” molecules into “right-handed” ones by using light to induce a proton transfer and the transformation into a different isomer. Now, Hanson and his fellow FSU Professor of Chemistry Eugene DePrince are harnessing the power of math and computers to predict what would happen if you performed that same process in a gap between closely spaced mirrors.

Parasite common in cats causes abortion in bighorn sheep

Bighorn sheep
Photo Credit: David Mark

A parasite believed to be present in more than 40 million people in the United States and often spread by domestic and wild cats could hamper ongoing conservation efforts in bighorn sheep.

A recent study led by Washington State University researchers at the Washington Animal Disease Diagnostic Laboratory found that Toxoplasma gondii, a parasite that infects most species of warm-blooded animals and causes the disease toxoplasmosis, is a cause of abortions, or pregnancy loss, as well as neonatal deaths in the sheep. Researchers documented five cases in bighorn sheep in a study published in the Journal of Wildlife Diseases, but additional studies are needed to determine the full scope of its impact, the authors said.

“We have seen Toxoplasma as a cause of fetal and neonate loss pretty commonly in domestic sheep, but we hadn’t seen pregnancy loss due to toxoplasmosis yet in bighorn sheep,” said Elis Fisk, the lead author of the study. “Unfortunately, it does appear to be causing abortions and some level of death in young bighorn lambs.”