Banned Contaminants Still Threaten Endangered California Condors

Condors at Pinnacles National Park in central California.

Photo courtesy of San Diego Zoo Wildlife Alliance

A new study has found contaminants that were banned decades ago are still imperiling critically endangered California condors. The condors may be at increased risk for reproductive impairment because they consume dead marine mammals along the California coast.

The research, led by San Diego State University (SDSU) and San Diego Zoo Wildlife Alliance (SDZWA) scientists, in collaboration with Centro de Investigación Científica y de Educación Superior de Ensenada and the National Oceanographic and Atmospheric Administration, found that marine mammals stranded on the California coast harbor relatively high levels of halogenated organic contaminants (HOCs). Researchers detected more than 400 contaminants in samples taken from stranded marine mammals that California condors may feed on.

On the California coast, the marine mammals had an estimated seven times more DDT and 3.5 times more PCBs than their counterparts in Baja California, Mexico. Other lesser-studied compounds were also detected. One group of these compounds was estimated to be 148 times more abundant in California marine mammals compared to those in Baja California.

The study, published in the journal Environmental Science & Technology, also reveals that coastal condors have more contaminants in their blood than inland condors, which lack a marine mammal diet.

Choline makes key nutrients available for baby development

Choline Molecule 
Choline occurs in foods as a free molecule and in the form of phospholipids, especially as phosphatidylcholines. Choline is highest in organ meats and egg yolks though it is found to a lesser degree in non-organ meats, grains, vegetables, fruit and dairy products.

The nutrient choline – shown to have long-term benefits for children whose mothers consume it during pregnancy – also helps the body more efficiently use an omega 3 fatty acid that is essential for fetal brain, cognition and vision development, a new study finds.

The study was published in the American Journal of Clinical Nutrition.

The findings show that choline supplementation supports cellular metabolism to more efficiently handle and release the omega 3 fatty acid, DHA, from a pregnant individual’s liver. Once released into the bloodstream, DHA can be delivered into all the tissues, including the placenta.

“During pregnancy, mom is primed to get nutrients out of the liver and make them available to the baby, so by supplementing choline and DHA [together], we are increasing DHA bioavailability,” said senior author Marie Caudill, professor of nutritional sciences in the College of Agriculture and Life Sciences. Kevin Klatt, Ph.D. ’18, a research scientist and registered dietitian at the University of California, Berkeley, is the paper’s first author.

Rainforest trees may have been dying faster since the 1980s because of climate change

Northeast Australia's relict tropical rainforest are one of the oldest most isolated rainforests in the world.
Photo credit: Alexander Schenkin

Tropical trees in Australia’s rainforests have been dying at double the previous rate since the 1980s, seemingly because of climate impacts, according to the findings of a long-term international study published in Nature today. This research has found the death rates of tropical trees have doubled in the last 35 years, as global warming increases the drying power of the atmosphere.

Deterioration of such forests reduces biomass and carbon storage, making it increasingly difficult to keep global peak temperatures well below the target 2 °C, as required by the Paris Agreement. Today’s study, led by researchers from the Smithsonian Environmental Research Center and Oxford University, and French National Research Institute for Sustainable Development (IRD), has used uniquely long data records from across Australia’s rainforests.

It finds average tree death rates in these forests have doubled over the past four decades. Researchers found trees are living around half as long, which is a pattern consistent across species and sites across the region. And the impacts can be seen as far back as the 1980s, according to the team.

Researchers Use Galaxy as a ‘Cosmic Telescope’ to Study Heart of the Young Universe

An artist’s rendering shows how a cluster of galaxies (lensing cluster) acts as a gravitational lens that magnifies and extends the light from a background galaxy.
Image: W. M. Keck Observatory/Adam Makarenko

A unique new instrument, coupled with a powerful telescope and a little help from nature, has given researchers the ability to peer into galactic nurseries at the heart of the young universe.

After the big bang some 13.8 billion years ago, the early universe was filled with enormous clouds of neutral diffuse gas, known as Damped Lyman-α systems, or DLAs. These DLAs served as galactic nurseries, as the gases within slowly condensed to fuel the formation of stars and galaxies. They can still be observed today, but it isn’t easy.

“DLAs are a key to understanding how galaxies form in the universe, but they are typically difficult to observe since the clouds are too diffuse and don’t emit any light themselves,” says Rongmon Bordoloi, assistant professor of physics at North Carolina State University and corresponding author of the research.

Currently, astrophysicists use quasars – supermassive black holes that emit light – as “backlight” to detect the DLA clouds. And while this method does allow researchers to pinpoint DLA locations, the light from the quasars only acts as small skewers through a massive cloud, hampering efforts to measure their total size and mass.

But Bordoloi and John O’Meara, chief scientist at the W.M. Keck Observatory in Kamuela, Hawaii, found a way around the problem by using a gravitationally lensed galaxy and integral field spectroscopy to observe two DLAs – and the host galaxies within – that formed around 11 billion years ago, not long after the big bang.

“Gravitationally lensed galaxies refer to galaxies that appear stretched and brightened,” Bordoloi says. “This is because there is a gravitationally massive structure in front of the galaxy that bends the light coming from it as it travels toward us. So, we end up looking at an extended version of the object – it’s like using a cosmic telescope that increases magnification and gives us better visualization.

“The advantage to this is twofold: One, the background object is extended across the sky and bright, so it is easy to take spectrum readings on different parts of the object. Two, because lensing extends the object, you can probe very small scales. For example, if the object is one light year across, we can study small bits in very high fidelity.”

Spectrum readings allow astrophysicists to “see” elements in deep space that are not visible to the naked eye, such as diffuse gaseous DLAs and the potential galaxies within them. Normally, gathering the readings is a long and painstaking process. But the team solved that issue by performing integral field spectroscopy with the Keck Cosmic Web Imager.

Integral field spectroscopy allowed the researchers to obtain a spectrum at every single pixel on the part of the sky it targeted, making spectroscopy of an extended object on the sky very efficient. This innovation combined with the stretched and brightened gravitationally lensed galaxy allowed the team to map out the diffuse DLA gas in the sky at high fidelity. Through this method the researchers were able to determine not only the size of the two DLAs, but also that they both contained host galaxies.

“I’ve waited most of my career for this combination: a telescope and instrument powerful enough, and nature giving us a bit of lucky alignments to study not one but two DLAs in a rich new way,” O’Meara says. “It’s great to see the science come to fruition.”

The DLAs are huge, by the way. With diameters greater than 17.4 kiloparsecs, they’re more than two thirds the size of the Milky Way galaxy today. For comparison, 13 billion years ago, a typical galaxy would have a diameter of less than 5 kiloparsecs. A parsec is 3.26 light years, and a kiloparsec is 1,000 parsecs, so it would take light about 56,723 years to travel across each DLA.

“But to me, the most amazing thing about the DLAs we observed is that they aren’t unique – they seem to have similarities in structure, host galaxies were detected in both, and their masses indicate that they contain enough fuel for the next generation of star formation,” Bordoloi says. “With this new technology at our disposal, we are going to be able to dig deeper into how stars formed in the early universe.”

The work appears in Nature and was supported by the National Aeronautics and Space Administration, the W.M. Keck Foundation and the National Science Foundation. The Australian Research Council Centre of Excellence for All Sky Astrophysics in 3 Dimensions (ASTRO 3D) also contributed to the work.

Source/Credit: North Carolina State University | Tracey Peake

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Spying on Thousands of Neurons in the Brain’s Vision Center Simultaneously

Scientists tracked how individual neurons (white dots)
across the mouse visual center responded when the
animals saw an image on a screen.
That let the team trace the sequence
of events triggered when the eyes detect an important sight.
Credit: S. Ebrahimi et al./Nature 2022

Using a custom-built microscope to peer into the mouse brain, scientists have tracked the activity of single neurons across the entire visual cortex.

These recordings, made in the tenths of seconds after the animals saw a cue on a screen, expose the complex dynamics involved in making sense of what the eyes see. In an unprecedented combination of breadth and detail, the results describe the behavior of more than 21,000 total neurons in six mice over five days, Howard Hughes Medical Institute Investigator Mark Schnitzer’s team reports in the journal Nature on May 18, 2022.

His team is the first to get a glimpse of individual cells’ activity occurring at the same time throughout eight parts of the brain involved in vision. “People have studied these brain areas before, but prior imaging studies did not have cellular resolution across the entire visual cortex,” says Schnitzer, a neuroscientist at Stanford University.

The work highlights the dramatic sequence of events that unfolds in the brain from the instant it receives messages from the eyes until it decides how to respond to that sight. The researchers’ far-reaching but fine-grained imaging approach made it possible for them to collect an “incredible” set of data, says Tatiana Engel, a computational neuroscientist at Cold Spring Harbor Laboratory who was not involved in the study.

A component for brain-inspired computing

Scientists aim to perform machine-learning tasks more efficiently with processors that emulate the working principles of the human brain.
Image: Unsplash

Researchers from ETH Zurich, Empa and the University of Zurich have developed a new material for an electronic component that can be used in a wider range of applications than its predecessors. Such components will help create electronic circuits that emulate the human brain and that are more efficient than conventional computers at performing machine-learning tasks.

Compared with computers, the human brain is incredibly energy-efficient. Scientists are therefore drawing on how the brain and its interconnected neurons function for inspiration in designing innovative computing technologies. They foresee that these brain-inspired computing systems will be more energy-efficient than conventional ones, as well as better at performing machine-learning tasks.

Much like neurons, which are responsible for both data storage and data processing in the brain, scientists want to combine storage and processing in a single type of electronic component, known as a memristor. Their hope is that this will help to achieve greater efficiency because moving data between the processor and the storage, as conventional computers do, is the main reason for the high energy consumption in machine-learning applications.

At-Risk Sea Life in the Atlantic Needs Better Protection from an Increase in Shipping

Researchers at the University of Portsmouth have discovered that rates of shipping in the North East Atlantic area rose by 34 per cent in a five-year period.

Even more noticeable, and of major concern to scientists, is the rate of shipping growth in Marine Protected Areas. Analysis of vessel movements in these delicate environments shows an increase of 73 per cent in the same time period.

The report, which was published in Marine Pollution Bulletin, is the first detailed survey of shipping activity in the North East Atlantic. Researchers used data from over 530 million vessel positions recorded by Automatic identification Systems (AIS). They looked at the change in shipping between 2013 and 2017 across ten distinct vessel types.

In total the study area covered 1.1 million km2, including waters off Belgium, Denmark, France, Germany, Iceland, Ireland, The Netherlands, Norway, Portugal, Spain, and the UK.

Renewed monitoring effort is needed to ensure that protective measures are adequate to conserve species under threat in a changing environment.

For Plant-based Proteins, Soy is a Smart Choice

Tofu, flour, milk, and sauce are just some of the products that can be made from the versatile plant protein soy

Soy – the versatile protein source that comes from the species of legumes known as soybeans – is becoming a popular alternative to meat and dairy products, and for good reason. Whether you are trying to eat healthier, eat more sustainably, or both, College of Agriculture, Health and Natural Resources Department of Nutritional Sciences researcher Yangchao Luo and his research group recently published an article in the Journal of Agriculture and Food Research exploring qualities that make soy a versatile and nutritious choice.

What makes soy such a popular source of plant-based meat (and dairy) alternatives?

In comparison to other plant-based proteins, soy protein provides the most complete nutrients in terms of amino acids, compared to animal sources. Soy contains almost every amino acid, with only one minor exception, methionine, which is an essential amino acid, and what we call a limiting amino acid. Other plant-based proteins may miss two, three, or even four different essential amino acids. You can easily get all essential amino acids in a meal by mixing plant-based proteins or by pairing soy-based proteins with grains.

Upon extrusion process, soy-based proteins undergo a series of physicochemical changes to form fibrous anisotropic structure, the texture of which becomes very similar to meat products. When modified chemically or enzymatically, soy protein can further develop sensory characteristics that can mimic real meat. This is very easy to do for soy protein, but more challenging for many other plant proteins. A lot of food companies nowadays are trying to develop meat alternatives, and soy-based protein is just the top choice for the food industries.

Ultrahigh piezoelectric performance demonstrated in ceramic materials

The ability of piezoelectric materials to convert mechanical energy into electrical energy and vice versa makes them useful for various applications from robotics to communication to sensors. A new design strategy for creating ultrahigh-performing piezoelectric ceramics opens the door to even more beneficial uses for these materials, according to a team of researchers from Penn State and Michigan Technological University.

“For a long time, piezoelectric polycrystalline ceramics have shown limited piezoelectric response in comparison to single crystals,” said Shashank Priya, associate vice president for research and professor of materials science and engineering at Penn State and co-author of the study published in the journal Advanced Science. “There are many mechanisms that limit the magnitude of piezoelectricity in polycrystalline ceramic materials. In this paper, we demonstrate a novel mechanism that allows us to enhance the magnitude of the piezoelectric coefficient several times higher than is normally expected for a ceramic.”

The piezoelectric coefficient, which describes the level of a material's piezoelectric response, is measured in picocoulombs per Newton.

“We achieved close to 2,000 picocoulombs per Newton, which is a significant advance, because in polycrystalline ceramics, this magnitude has always been limited to around 1,000 picocoulombs per Newton,” Priya said. "2,000 was considered an unreachable target in the ceramics community, so achieving that number is very dramatic.”

Rice chemists skew the odds to prevent cancer

A new paper by a Rice University lab shows how to increase the odds of identifying cancer-causing mutations before tumors take hold. Authors are, from left, Cade Spaulding, Anatoly Kolomeisky and Hamid Teimouri.
Credit: Rice University

The path to cancer prevention is long and arduous for legions of researchers, but new work by Rice University scientists shows that there may be shortcuts.

Rice chemist Anatoly Kolomeisky, lead author and postdoctoral researcher Hamid Teimouri and research assistant Cade Spaulding are developing a theoretical framework to explain how cancers caused by more than one genetic mutation can be more easily identified and perhaps stopped.

Essentially, it does so by identifying and ignoring transition pathways that don’t contribute much to the fixation of mutations in a cell that goes on to establish a tumor.

A study in the Biophysical Journal describes their analysis of the effective energy landscapes of cellular transformation pathways implicated in a variety of cancers. The ability to limit the number of pathways to the few most likely to kick-start cancer could help to find ways to halt the process before it ever really starts.

“In some sense, cancer is a bad-luck story,” said Kolomeisky, a professor of chemistry and of chemical and biomolecular engineering. “We think we can decrease the probability of this bad luck by looking for low-probability collections of mutations that typically lead to cancer. Depending on the type of cancer, this can range between two mutations and 10.”