Blind spots when monitoring plastic waste

The researchers used river models that were filled with plastic waste for their investigation
Photo Credit: Daniel Valero, KIT

Whether in drinking water, in food or even in the air: plastic is a global problem - and the full extent of the pollution may not be known yet. Researchers at the Karlsruhe Institute of Technology (KIT), together with partners from the Netherlands and Australia, have reviewed conventional assumptions for the transport of plastic in rivers. The actual amount of plastic waste in rivers could therefore be up to 90 percent larger than previously thought. The new findings are intended to help improve monitoring and remove plastic from water. They report on their results in the journal Water Research.

Rivers play a key role in the transportation of plastic in the environment. "As soon as plastic gets into a river, it is transported at high speed and spread in the environment," says Dr. Daniel Valero from the KIT Institute for Water and Water Development and lead author of the current study on plastic transport. “But depending on the size and nature, plastic can behave very differently. It can be dipped, swimming or stopped by obstacles. "Current methods for estimating plastic pollution in rivers are based as standard but mainly on surface observations. “This is the only way to effectively monitor large rivers from bridges. However, the underlying assumptions have not yet been adequately reviewed,” said Valero.

500 million year-old fossils reveal answer to evolutionary riddle

Fossil specimen (left) and diagram (right) of Gangtoucunia aspera preserving soft tissues, including the gut and tentacle.
Image Credit: Luke Parry and Guangxu Zhang.

An exceptionally well-preserved collection of fossils discovered in eastern Yunnan Province, China, has enabled researchers to solve a centuries-old riddle in the evolution of life on earth, revealing what the first animals to make skeletons looked like. The results have been published today in Proceedings of the Royal Society B.

The first animals to build hard and robust skeletons appear suddenly in the fossil record in a geological blink of an eye around 550-520 million years ago during an event called the Cambrian Explosion. Many of these early fossils are simple hollow tubes ranging from a few millimetres to many centimetres in length. However, what sort of animals made these skeletons was almost completely unknown, because they lack preservation of the soft parts needed to identify them as belonging to major groups of animals that are still alive today.

The new collection of 514-million-year-old fossils includes four specimens of Gangtoucunia aspera with soft tissues still intact, including the gut and mouthparts. These reveal that this species had a mouth fringed with a ring of smooth, unbranched tentacles about 5 mm long. It’s likely that these were used to sting and capture prey, such as small arthropods. The fossils also show that Gangtoucunia had a blind-ended gut (open only at one end), partitioned into internal cavities, that filled the length of the tube.

Study urges caution when comparing neural networks to the brain

Neural networks, a type of computing system loosely modeled on the organization of the human brain, form the basis of many artificial intelligence systems for applications such speech recognition, computer vision, and medical image analysis.
Image Credits: Christine Daniloff | Massachusetts Institute of Technology

Neural networks, a type of computing system loosely modeled on the organization of the human brain, form the basis of many artificial intelligence systems for applications such speech recognition, computer vision, and medical image analysis.

In the field of neuroscience, researchers often use neural networks to try to model the same kind of tasks that the brain performs, in hopes that the models could suggest new hypotheses regarding how the brain itself performs those tasks. However, a group of researchers at MIT is urging that more caution should be taken when interpreting these models.

In an analysis of more than 11,000 neural networks that were trained to simulate the function of grid cells — key components of the brain’s navigation system — the researchers found that neural networks only produced grid-cell-like activity when they were given very specific constraints that are not found in biological systems.

“What this suggests is that in order to obtain a result with grid cells, the researchers training the models needed to bake in those results with specific, biologically implausible implementation choices,” says Rylan Schaeffer, a former senior research associate at MIT.

Viruses can ‘hitchhike’ on microplastics

Photo Credit: Naja Bertolt Jensen

Microplastics are not just tiny particles that can be ingested, they can also carry viruses, a University of Queensland study has revealed.

The study, led by Associate Prof Jianhua Guo and Dr Ji Lu from UQ’s Australian Centre for Water and Environmental Biotechnology (ACWEB), investigated if microplastics have the ability to harbor viruses, including the one found inside E. coli bacteria.

“We often hear about the human and environmental harm caused by microplastics in water, but there is little known about whether the tiny microplastic particles can carry viruses,” Dr Guo said.

“What we found is that viruses can hitchhike on microplastics and prolong their infectivity, which means there could be an increased risk of virus transmission throughout waterways and the environment.”

Dr Lu said they used the E. coli bacteriophage in the study, which is a virus that infects and replicates within the bacteria itself and is not harmful to humans.

Daytime Naps Reinforce Memories of Emotional Trauma and Anxiety

According to Yuri Pavlov, the positive effect of sleep on memory can be observed years later.
Photo Credit: Nadezhda Pavlova

Scientists from Ural Federal University and the University of Tübingen (Germany) studied the effect of sleep on the formation and translation of primary memories of something scary into long-term memory. Neurobiologists discovered that sleeping during the day strengthens memory of disturbing and frightening events, but a similar effect of memory strengthening is also observed after a period of calm wakefulness. The findings will be useful for developing rehabilitation strategies for people who have been emotionally traumatized by disasters, warfare, and violence. The study was published in the journal Cognitive, Affective, & Behavioral Neuroscience.

Memory consolidation - the transition of memories from short-term memory to long-term memory - occurs primarily during sleep. Studies show that sleep after learning can have positive effects that are superior to passive wakefulness. This occurs by reactivating important memories, which may also be reflected in dreams. The positive effects of dreaming can be observed even years later. However, there are currently no studies that analyze whether sleep enhances the effect of remembering emotionally difficult events. Therefore, scientists decided to find out how sleep affects the memory of a person's experience of fear.

Method to char­ac­ter­ize large quan­tum com­put­ers

View inside an ion trap, the heart of an ion trap quantum computer. 
Credit: C Lackner/Quantum Optics and Spectroscopy Group, University of Innsbruck

Quantum devices are becoming ever more complex and powerful. Researchers at the University of Innsbruck, in collaboration with the Johannes Kepler University Linz and the University of Technology Sydney, are now presenting a method to characterize even large quantum computers using only a single measurement setting.

The gold-standard for the characterization of quantum devices is so-called quantum tomography, which in analogy to medical tomography, can draw a complete picture of a quantum system from a series of snapshots of the system. While offering plenty of insights, the number of measurements required for tomography increases rapidly, with three times as many measurements required for every additional qubit. Due to the sheer time it takes to perform all these measurements, tomography has only been possible on devices with a handful of qubits. However, recent developments on quantum computers have successfully scaled up system sizes much beyond the capabilities of tomography, making their characterization a daunting bottleneck.

A new method for studying ribosome function

Illustration showing the principle of native chemical ligation approach developed by Syroegin, et al. Addition of the cysteine amino acid (red) to tRNA (blue, top left) allows for the tRNA to fuse to a peptide (yellow, lower left). The resulting ribosome structure (middle) and the captured electron density maps for the peptidyl-tRNA inside the ribosome (right) were obtained by X-ray crystallography in the UIC experiments.
Image Credit: Syroegin, et al.

Inside tiny cellular machines called ribosomes, chains of genetic material called messenger RNAs (mRNAs) are matched with the corresponding transfer RNAs (tRNAs) to create sequences of amino acids that exit the ribosome as proteins. Unfinished proteins are called nascent chainsm and they are left attached to the ribosome.

Scientists know that some of these nascent chains can regulate the activity of the ribosome and that the nascent chains can sometimes interfere with antibiotics — many of which work by targeting bacterial ribosome activity. Scientists do not know why this happens, mainly because it is hard to visualize what the ribosome-peptide-drug interactions look like while the unfinished proteins are still tethered to the ribosome.

Now, scientists at the University of Illinois Chicago are the first to report a method for stable attachment of peptides to tRNAs, which has allowed them to gain new fundamental insights into ribosome function by determining the atomic-level structures of ribosomes and the shapes that these peptides take inside the ribosome.

How much microplastic do whales eat? Up to 10 million pieces per day

Humpback whales lunge feed in Monterey Bay. New research shows whales are ingesting plastic in larger quantities than previously thought, and nearly all comes from their prey, not from the enormous volumes of seawater the whales gulp when feeding.
Photo Credit: shadowfaxone

Analysis of ocean plastic pollution and whale foraging behavior tracked with noninvasive tags shows whales are ingesting tiny specks of plastic in far bigger quantities than previously thought, and nearly all of it comes from the animals they eat – not the water they gulp.

The largest animals ever known to have lived on Earth ingest the tiniest specks of plastic in colossal amounts, Stanford University scientists have found.

Published in Nature Communications, the study focuses on blue, fin, and humpback whales and their consumption of plastic fragments no bigger than a few grains of sand, which are commonly called microplastics. The authors combined measures of microplastic concentrations up and down the water column off the coast of California with detailed logs of where hundreds of whales carrying tracking devices foraged for food between 2010 and 2019.

They found the whales predominantly feed 50 to 250 meters below the surface, a depth that coincides with the highest concentrations of microplastic in the open ocean. The planet’s biggest creature – the blue whale – ingests the most plastic, at an estimated 10 million pieces per day as it feeds almost exclusively on shrimplike animals called krill.

“They’re lower on the food chain than you might expect by their massive size, which puts them closer to where the plastic is in the water. There’s only one link: The krill eats the plastic, and then the whale eats the krill,” said study co-author Matthew Savoca, a postdoctoral scholar at Hopkins Marine Station, Stanford’s marine laboratory on the Monterey Peninsula.

Arctic Hydrothermal Vent Site Could Help in Search for Extraterrestrial Life

The view from over ice-floes in the Arctic Ocean, covering the Aurora hydrothermal Field, Gakkel Ridge from the R/V Polarstern.
Photo Credit Chris German, ©Woods Hole Oceanographic Institution

When scientists discovered a hydrothermal vent site in the Arctic Ocean’s Aurora hydrothermal system in 2014, they did not immediately realize just how exciting their discovery was.

“Although finding any vent in the Arctic Ocean was a first, we figured what we had found was one of the least interesting kinds of vent sites that there are,” said Chris German, senior scientist with the Woods Hole Oceanographic Institution’s Department of Geology and Geophysics. “We came home from the expedition thinking, ‘Okay, we found a site in the Arctic. That’s great, but if you take away the ice-cover, it is just another vent site’.”

However, after further analysis and a follow-on 2019 expedition to the remote site, German and other researchers now think this is a very significant finding. They believe that this vent—and others still to be located within the Arctic Ocean’s Gakkel Ridge rift-valley floor—could change our understanding of ultra-slow spreading mid-ocean ridges, substantially expand the estimates of valuable marine mineral deposits rich in copper and gold and serve as natural laboratories to help inform the search for extraterrestrial life.

“Our findings have implications for ultra-slow ridge cooling, global marine mineral distributions, and the diversity of geologic settings that can host abiotic organic synthesis–pertinent to the search for life beyond Earth,” according to the paper, “Volcanically hosted venting with indications of ultramafic influence at Aurora hydrothermal field on Gakkel Ridge,” published in Nature Communications.

A New Protocol for Live Imaging Emerges from MBL Embryology Course

A stylized image of a nematode worm (C. elegans) adult encircled by embryos.
Credit: Yicong Wu

The beauty of live-imaging studies is that the specimen is alive, allowing dynamics such as cell division and embryonic development to be recorded over time.

Yet the frustration of live-imaging studies is the specimen is alive – wriggling, twisting, escaping the field of view. Plus, it’s delicate, susceptible to heat damage or death from the imaging equipment itself.

A technical solution to this quandary recently emerged from the MBL Embryology course, in “a classic example of the collaborative effort here at MBL,” says MBL Imaging Research Specialist Carsten Wolff.

“During the 2021 Embryology course, we started to develop a technique that enables us to image adult C. elegans worms for longer periods of time, and at high resolution, using light sheet microscopy,” says Wolff. A group of course faculty and staff, collaborating with MBL imagers, fine-tuned the protocol during the 2022 course and wrote up the paper, which is published this month in Frontiers in Cell and Developmental Biology.

The nematode C. elegans is a popular organism in biological and biomedical research. Light-sheet fluorescence microscopy (LSFM) has been very successful in capturing embryonic processes in C. elegans, as well as in mice and zebrafish. But once the organisms hatch out, LSFM presents limitations.

As dense as it gets: New Model for Matter in Neutron Star Collisions

Illustration of the new method: the researchers use five-dimensional black holes (right) to calculate the phase diagram of strongly coupled matter (middle), enabling simulations of neutron star mergers and the produced gravitational waves (left).
Source/Credit: Goethe University

With the exception of black holes, neutron stars are the densest objects in our universe. As their name suggests, neutron stars are mainly made of neutrons. However, our knowledge about the matter produced during the collision of two neutron stars is still limited. Scientists from Goethe University Frankfurt and the Asia Pacific Center for Theoretical Physics in Pohang have now developed a new model that gives insights about matter under such extreme conditions.

After a massive star has burned its fuel and explodes as a supernova, an extremely compact object, called a neutron star, can be formed. Neutron stars are extraordinarily dense: To reach the density inside them, one would need to squeeze a massive body like our sun down to the size of a city like Frankfurt. In 2017, gravitational waves, the small ripples in spacetime that are produced during a collision of two neutron stars, could be directly measured here on earth for the first time. However, the composition of the resulting hot and dense merger product is not known precisely. It is still an open question, for instance, whether quarks, which are otherwise trapped in neutrons, can appear in free form after the collision. Dr. Christian Ecker from the Institute for Theoretical Physics of Goethe University Frankfurt, Germany, and Dr. Matti Järvinen and Dr. Tuna Demircik from the Asia Pacific Center for Theoretical Physics in Pohang, South Korea, have now developed a new model that allows them to get one step closer to answering this question.

Learning to Better Understand the Language of Algae

A view through the microscope onto the diverse microalgal community of a freshwater lake, including diatoms, green algae and dinoflagellates/chryosphytes.
Photo: Maria Stockenreiter /LMU München

Communication is everything - and that applies for algae, too. However, their chemical language and its significance in aquatic ecosystems remain largely unknown. A research duo from the Helmholtz Centre for Environmental research (UFZ) and the Plymouth Marine Laboratory (PML) have published a corresponding review in Biological Reviews. This summarizes the current state of knowledge and identifies new approaches for future research in the language of algae and their ecological relationships.

Can algae talk? "Well, although they don't have any mouth or ears, algae still communicate with their own kind and with other organisms in their surroundings. They do this with volatile organic substances they release into the water," says Dr. Patrick Fink, a water ecologist at the UFZ's Magdeburg site. These chemical signals are known as BVOCs (biogenic volatile organic compounds) and are the equivalent of odors in the air with which flowering plants communicate and attract their pollinators. When under attack by parasites, some plant species release odors that attract the parasites' natural enemies to them. "Algae also employ such interactions and protective mechanisms," says Fink. "After all, they are among the oldest organisms on Earth, and chemical communication is the most original form of exchanging information in evolutionary history. However, our knowledge in this area still remains very fragmentary."

New Technique Helps ID Genes Related to Aging

The head of a C. elegans showing fluorescently labeled protein aggregates.
Source: North Carolina State University

Researchers from North Carolina State University have developed a new method for determining which genes are relevant to the aging process. The work was done in an animal species widely used as a model for genetic and biological research, but the finding has broader applications for research into the genetics of aging.

“There are a lot of genes out there that we still don’t know what they do, particularly in regard to aging,” says Adriana San Miguel, corresponding author of a paper on the work and an assistant professor of chemical and biomolecular engineering at NC State. “That’s because this field faces a very specific technical challenge: by the time you know whether an organism is going to live for a long time, it’s old and no longer able to reproduce. But the techniques we use to study genes require us to work with animals that are capable of reproducing, so we can study the role of specific genes in subsequent generations.

“To expedite research in this field, we wanted to find a way of identifying genes that may be relevant to aging while the organisms are still young enough to work with.”

For this work, the researchers focused on a species of roundworm called C. elegans, which is one of the most important model species for research into genetics and aging. Specifically, the researchers focused on protein aggregation in cells, which is well established as being related to aging.

Pancreatic cancer could be diagnosed up to three years earlier

The desmoplastic reaction is a prominent pathological characteristic of pancreatic cancer. 
Credit: National Cancer Institute

Pancreatic cancer could be identified in patients up to three years earlier than current diagnoses, new research suggests. Weight loss and increasing blood glucose levels are early indicators of pancreatic cancer and could lead to a timelier diagnosis, helping to improve survival rates.

In the largest study of its kind, researchers from the University of Oxford, in partnership with Pancreatic Cancer Action and the University of Surrey, investigated signs of pancreatic cancer, including weight loss, hyperglycemia and diabetes and demonstrated the timelines for when they develop in relation to cancer. The pancreas is a vital organ with two key functions, to produce insulin and digestive enzymes. Cancer can affect one or both of these functions leading to the above symptoms. Currently, almost 90 per cent of people with pancreatic cancer are diagnosed too late for curative treatment.

Lead author Dr Agnieszka Lemanska, Lecturer in Data Science at the University of Surrey, said: 'Due to the difficulty in detecting pancreatic cancer, survival rates are extremely poor compared to other cancers, with less than 10 per cent of people surviving five years or more after diagnosis.

'Weight loss and increased blood glucose are recognized symptoms of pancreatic cancer. However, the extent of these symptoms and when they manifest have been unknown. Knowing when they develop will help clinicians to diagnose this deadly cancer, meaning treatment can begin earlier.'

Physicists Proposed Theory of Solidification of Nickel and Iron Alloys

Nickel-iron alloy is used when high dimensional stability of finished parts is required.
Photo: unsplash.com / Laura Ockel

Physicists at Ural Federal University have created a theory for the solidification of a nickel-iron alloy (invar). They determined that an important role in the technology of creating products from invar, namely in the solidification process, is played by the oncoming flow: when the alloy cools, the liquid layer flows on top of the solidified layer. If you regulate this process, you can control the characteristics of the alloys, obtain a more homogeneous structure, thereby improving the properties of the final product.

The work of scientists is extremely important because nickel and iron alloys are used in creating high-precision devices: clocks, seismic sensors, substrates for chips, valves and engines in aircraft structures, and instruments for telescopes. The calculations will help to create an alloy with the desired structure, which will affect the quality of the finished products. Description of the model and behavior of melts, as well as analytical calculations, scientists have published in the journal Scientific Reports. The research was supported by the Russian Science Foundation (Project No. 21-79-10012).

"Let me explain the work with an analogy. When water freezes, it pushes out all the dirt. So, you can put a piece of ice in your mouth, it will be clean. This is roughly what happens to melts when they cool. The only difference is that they do not push out all the impurities, but some of them. Some of the impurities leak out, and some of the impurities stay in the melt. What remains in the melt fills the gaps between the crystals, which solidify, and the voids, which remain. As a result, the alloys are heterogeneous: one tiny piece is enriched and the neighboring piece is not. This affects the properties of the finished product," says Dmitry Aleksandrov, Head of the Ural Federal University's Laboratory of Multi-Scale Mathematical Modeling.