Studying Polymer Gels Through the Lens of Mechanochemistry and Solvent Swelling

Multinetwork polymer gels with color-changing linkers sensitive to mechanical stimuli provide a solid platform to study the dynamics of solvent swelling, as shown by researchers from Tokyo Tech. This innovative approach allowed them to gain detailed insight into the mechanical forces that a gel is subjected to when swollen after absorbing a solvent. Their findings will pave the way to developing new, mechanically responsive materials for many applications.

Polymer gels have become a staple technology in various fields, ranging from optics and drug delivery to carbon capture and batteries. However, there are still many open questions about gels and their network structure, which has prevented scientists from linking their remarkable macroscopic properties to specific molecular mechanisms.

One interesting way to tackle this puzzle is to study it from the lens of mechanochemistry; that is, chemical reactions that are triggered by mechanical stimuli such as compression, stretching, and grinding. To make this process easier, scientists can weave mechanophores into polymer networks. These are molecules that undergo predictable chemical changes upon exposure to mechanical stress. While there are many ways to apply mechanical forces to activate mechanophores in a gel, one has been studied in much less detail than others: solvent swelling.

Tumultuous migration on the edge of the Hot Neptune Desert

Did hot Neptunes ever exist? While astronomers observe gas giants and small rocky planets close to their stars, the SPICE DUNE project is investigating the ‘‘desert’’ of Neptune-sized planets.
Illustration Credit: © Elsa Bersier - CFPArts / ESBDi Genève

A UNIGE team reveals the eventful migration history of planets bordering the Hot Neptune Desert, these extrasolar planets that orbit very close to their star.

 All kinds of exoplanets orbit very close to their star. Some look like the Earth, others like Jupiter. Very few, however, are similar to Neptune. Why this anomaly in the distribution of exoplanets? Researchers from the University of Geneva (UNIGE) and the National Centre of Competence in Research (NCCR) PlanetS have observed a sample of planets located at the edge of this Hot Neptune Desert to understand its creation. Using a technique combining the two main methods of studying exoplanets (radial velocities and transits), they were able to establish that a part of these exoplanets has migrated in a turbulent way near their star, which pushed them out of the orbital plane where they were formed. These results are published in the specialized journal Astronomy & Astrophysics.

Wearable, Printable, Shapeable Sensors Detect Pathogens and Toxins in the Environment

“Using the sensor, we can pick up trace levels of airborne SARS-CoV-2, or we can imagine modifying it to adapt to whatever the next public health threat might be,” Omenetto said. Here, a sensor is embedded on a drone.
Photo Credit: Courtesy of Silklab

Researchers at Tufts School of Engineering have developed a way to detect bacteria, toxins, and dangerous chemicals in the environment using a biopolymer sensor that can be printed like ink on a wide range of materials, including wearable items such as gloves, masks, or everyday clothing.

Using an enzyme similar to that found in fireflies, the sensor glows when it detects these otherwise invisible threats. The new technology is described in the journal Advanced Materials.

The biopolymer sensor, which is based on computationally designed proteins and silk fibroin extracted from the cocoons of the silk moth Bombyx Mori, can also be embedded in films, sponges, and filters, or molded like plastic to sample and detect airborne and waterborne dangers, or used to signal infections or even cancer in our bodies.

The researchers demonstrated how the sensor emits light within minutes as it detects the SARS-CoV-2 virus that causes COVID, anti-hepatitis B virus antibodies, the food-borne toxin botulinum neurotoxin B, or human epidermal growth factor receptor 2 (HER2), an indicator of the presence of breast cancer.

Ancient chimaeras were suction feeders, not shell crushers, new research shows

Iniopera reconstruction
Resized Image using AI by SFLORG
Photo Credit: Richard Dearden / University of BIrmingham

A rare three-dimensional fossil of an ancient chimaera has revealed new clues about the diversity of these creatures in the Carboniferous period, some 300 million years ago.

Research led by the Muséum national d'histoire naturelle (MNHN) and the University of Birmingham has shown that an ancient relative of chimaeras – jawed vertebrates that are related to sharks and rays – fed by sucking in prey animals underwater.

The fossil, from a genus called Iniopera, is the only suction feeder to be identified among chimaeras, and quite different from living chimaeras, which feed by crushing mollusks and other hard-shelled prey between their teeth. The research is published in the journal PNAS.

New method for designing tiny 3D materials could make fuel cells more efficient

Authors of the study Professor Richard Tilley and Dr Lucy Gloag.
Photo Credit: UNSW Sydney / Courtesy of the researchers 

Researchers have developed an innovative technique for creating nanoscale materials with unique chemical and physical properties.

Scientists from UNSW Sydney have demonstrated a novel technique for creating tiny 3D materials that could eventually make fuel cells like hydrogen batteries cheaper and more sustainable.

In the study published in Science Advances, researchers from the School of Chemistry at UNSW Science show it’s possible to sequentially ‘grow’ interconnected hierarchical structures in 3D at the nanoscale which have unique chemical and physical properties to support energy conversion reactions.

In chemistry, hierarchical structures are configurations of units like molecules within an organization of other units that themselves may be ordered. Similar phenomena can be seen in the natural world, like in flower petals and tree branches. But where these structures have extraordinary potential is at a level beyond the visibility of the human eye – at the nanoscale.

Excavation of massive underground caverns for DUNE halfway complete

When complete later this year, this cavern will be around 500 feet long, 65 feet wide and 90 feet high. It will be one of three caverns that will provide space to house particle detector modules and other equipment for the Deep Underground Neutrino Experiment.
Photo Credit: David Smith, Fermilab

Deep below the surface in South Dakota, construction crews have been working tirelessly to carve out a network of caverns and tunnels that one day will house a huge neutrino experiment. Their efforts are paying off: With almost 400,000 tons of rock extracted from the earth, the excavation is now half complete.

Once finished, the Long-Baseline Neutrino Facility will be the site of the international Deep Underground Neutrino Experiment. DUNE will focus on studying neutrinos, elusive particles that may hold the answers to many of the universe’s mysteries, such as why our universe is made of matter and how black holes and neutron stars are born. More than 1,000 scientists and engineers from over 30 countries are a part of LBNF/DUNE.

LBNF will provide the space, infrastructure and particle beam for DUNE, hosted by the U.S. Department of Energy’s Fermi National Accelerator Laboratory. It includes underground caverns for a near detector at Fermilab, about 40 miles west of Chicago, and a far detector located 800 miles away at the Sanford Underground Research Facility in South Dakota.

Increased atmospheric dust is masking greenhouse gases’ warming effect

A visualization from space of the “Godzilla” dust storm on June 18, 2020, when desert dust traveled from the Sahara to North America. A UCLA study finds that an increase in microscopic dust in the atmosphere has concealed the full extent of greenhouse gases’ potential for warming the planet.
Image Credit: NASA Scientific Visualization Studio  

A new study shows that global atmospheric dust — microscopic airborne particles from desert dust storms — has a slight overall cooling effect on the planet that has hidden the full amount of warming caused by greenhouse gases.

The UCLA research, published today in Nature Reviews Earth and Environment, found that the amount of desert dust has grown roughly 55% since the mid-1800s, which increased the dust’s cooling effect.

This study is the first to demonstrate the overall cooling effect of atmospheric desert dust. Some effects of atmospheric dust warm the planet, but because other effects of dust actually counteract warming — for example by scattering sunlight back into space and dissipating high clouds that warm the planet — the study calculated that dust’s overall effect is a cooling one.

Should dust levels decline — or even simply stop growing — warming could ramp up, said UCLA atmospheric physicist Jasper Kok, the study’s lead author.

Climate Change Likely to Uproot More Amazon Trees

Members of NGEE-Tropics visit what they named “Blowdown Gardens,” an area that experienced windthrow near one of their field sites in the Amazon. Researchers have found a relationship between atmospheric conditions and large areas of tree death.
Photo Credit: Charlie Koven/Berkeley Lab

Tropical forests are crucial for sucking up carbon dioxide from the atmosphere. But they’re also subject to intense storms that can cause “windthrow” – the uprooting or breaking of trees. These downed trees decompose, potentially turning a forest from a carbon sink into a carbon source.

A new study finds that more extreme thunderstorms from climate change will likely cause a greater number of large windthrow events in the Amazon rainforest. This is one of the few ways that researchers have developed a link between storm conditions in the atmosphere and forest mortality on land, helping fill a major gap in models.

“Building this link between atmospheric dynamics and damage at the surface is very important across the board,” said Jeff Chambers, a senior faculty scientist at the Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab), and director of the Next Generation Ecosystem Experiments (NGEE)-Tropics project, which performed the research. “It’s not just for the tropics. It’s high-latitude, low-latitude, temperate-latitude, here in the U.S.”

Chemists Created a Substance with Potential Antitumor Activity

The new antitumor substance was synthesized at Ural Federal University's Scientific-educational and Innovation Center of Chemical and Pharmaceutical Technologies.
Photo Credit: Rodion Narudinov

New compound could be the basis of a drug for tumor cells

Chemists from the Ural Federal University and Volgograd State Medical University have created a compound that suppresses cancer cells. The powerful new substance could become the basis for antitumor drugs because it affects the pathology that leads to the development of malignant tumors, such as cancer of the breast, lung, prostate, and lymph nodes. The substance and the results of the experiments were published in the journal Molecules.

"Type 2 casein kinase (CK2) is known to suppress apoptosis in cells, but increased levels of type 2 casein kinase are observed in tumor cells, indicating that these cells are resistant to apoptosis compared to normal cells. If you block this protein, you can achieve tumor cell death. So, our team managed to develop a universal approach to the synthesis of new azolopyrimidines and obtain a library of corresponding heterocycles as potential inhibitors of casein kinase type 2," explains Grigory Urakov, an Engineer of the Scientific Laboratory of Medical Chemistry and Advanced Organic Materials at UrFU.

Chloroplast from the father

Tobacco seedlings on growth medium with an antibiotic. Plants with exclusively maternally inherited chloroplasts sensitive to the antibiotic are pale. Two seedlings contain green, intact chloroplasts in the leaves (red arrows). These chloroplasts are resistant to the antibiotic and were passed on from the father plant.
Image Credit: MPI-MP

Under cold conditions, not only the mother plant but also the father plant can pass on its chloroplasts to the offspring

Scientists at the Max Planck Institute of Molecular Plant Physiology in Potsdam (Germany) analyzed for the first time the inheritance of chloroplasts under a wide range of environmental conditions. Contrary to the prevailing view that chloroplasts are only passed on by the mother plant, paternal chloroplasts can also be transmitted to the offspring under cold conditions. Maternal and paternal chloroplasts thus meet in the offspring and may be able to exchange genetic material with each other. The new findings may allow plant breeders for the first time to selectively use traits from the genetic material of chloroplasts.

A story of flowers and bees is the classic introduction to a topic that is still discussed far too scarcely in our society: sex in plants! When plants reproduce, the sperms within the pollen grains fuse with the egg cell within the flower the pollen has landed on. In this way, the genetic material of the cell nuclei of both parents is combined in the seed. This is important, as it allows harmful mutations to be purged that otherwise would accumulate in the genetic material over generations.