New ‘chain mail’ material of interlocking molecules is tough, flexible and easy to make

The individual building blocks of a catenane are polyhedral molecules — a type of adamantane — that link arms to form a 2D mesh or 3D network that is sturdy but flexible.
Illustration Credit: Tianqiong Ma, UC Berkeley

University of California, Berkeley, chemists have created a new type of material from millions of identical, interlocking molecules that for the first time allows the synthesis of extensive 2D or 3D structures that are flexible, strong and resilient, like the chain mail that protected medieval knights.

The material, called an infinite catenane, can be synthesized in a single chemical step.

French chemist Jean-Pierre Sauvage shared the 2016 Nobel Prize in Chemistry for synthesizing the first catenane — two linked rings. These structures served as the foundation for making molecular structures capable of moving, which are often referred to as molecular machines.

But the chemical synthesis of catenanes has remained laborious. Adding each additional ring to a catenane requires another round of chemical synthesis. In the 24 years since Sauvage created a two-ring catenane, chemists have achieved, at most, a mere 130 interwoven rings in quantities too small to see without an electron microscope.

Cyborg Cells Could Be Tools for Health and Environment

UC Davis biomedical engineers have created semi-living “cyborg cells” that have many of the capabilities of living cells but are unable to divide and grow. The cells could have applications in medicine and environmental cleanup.
Illustration Credit: Cheemeng Tan, UC Davis.

Biomedical engineers at the University of California, Davis, have created semi-living “cyborg cells.” Retaining the capabilities of living cells, but unable to replicate, the cyborg cells could have a wide range of applications, from producing therapeutic drugs to cleaning up pollution. The work was published in Advanced Science.

Synthetic biology aims to engineer cells that can carry out novel functions. There are essentially two approaches in use, said Cheemeng Tan, associate professor of biomedical engineering at UC Davis and senior author on the paper. One is to take a living bacterial cell and remodel its DNA with new genes that give it new functions. The other is to create an artificial cell from scratch, with a synthetic membrane and biomolecules.

The first approach, an engineered living cell, has great flexibility but is also able to reproduce itself, which may not be desirable. A completely artificial cell cannot reproduce but is less complex and only capable of a limited range of tasks.

Data Reveal a Surprising Preference in Particle Spin Alignment

New data show that local fluctuations in the nuclear strong force may influence the spin orientation of particles called phi mesons (made of two quarks held together by the exchange of gluons).
Illustration Credit: Brookhaven National Laboratory

Given the choice of three different “spin” orientations, certain particles emerging from collisions at the Relativistic Heavy Ion Collider (RHIC), an atom smasher at the U.S. Department of Energy’s (DOE) Brookhaven National Laboratory, appear to have a preference. As described in a paper just published in Nature by RHIC’s STAR collaboration, the results reveal a preference in global spin alignment of particles called phi mesons. Conventional mechanisms—such as the magnetic field strength or the swirliness of the matter generated in the particle collisions—cannot explain the data. But a new model that includes local fluctuations in the nuclear strong force can.

“It could be that the strong force fluctuations are the missing factor. Previously we hadn’t realized the strong force can influence particle spin in this way,” said Aihong Tang, a STAR physicist at Brookhaven who was involved in the analysis.

This explanation is still subject to debate and further verification is needed, the STAR physicists say. But if it proves to be true, “these measurements give us a way to gauge how large the local fluctuations in the strong force are. They provide a new avenue to study the strong force from a different perspective,” Tang said.

Boeing Awarded NASA Sustainable Flight Demonstrator Contract

SFD Rendering
NASA has selected Boeing and its industry team to lead the development and flight testing of a full-scale Transonic Truss-Braced Wing (TTBW) demonstrator airplane.
Image Credit: Boeing

NASA has selected Boeing and its industry team to lead the development and flight testing of a full-scale Transonic Truss-Braced Wing (TTBW) demonstrator airplane.

The technologies demonstrated and tested as part of the Sustainable Flight Demonstrator (SFD) program will inform future designs and could lead to breakthrough aerodynamics and fuel efficiency gains.

When combined with expected advancements in propulsion systems, materials and systems architecture, a single-aisle airplane with a TTBW configuration could reduce fuel consumption and emissions up to 30% relative to today's most efficient single-aisle airplanes, depending on the mission. The SFD program aims to advance the civil aviation industry's commitment to reaching net zero carbon emissions by 2050, as well as the goals set forth in the White House's U.S. Aviation Climate Action Plan.

Artifacts, Begone! NIST Improves Its Flagship Device for Measuring Mass

For the first time, scientists have integrated a quantum resistance standard directly into mass measurements made with the one-of-a-kind NIST-4 Kibble balance. Using the quantum standard in this way increases the accuracy of the measurements. This animation shows how the new quantum resistance standard, called QHARS, works. The QHARS device uses a sheet of graphene (a single layer of carbon atoms) attached to superconducting electrical contacts. When cooled to low temperature and placed in a strong magnetic field, electrons in the graphene begin moving in closed loops, a phenomenon known as the quantum Hall effect. This behavior results in the graphene having a specific resistance, providing an absolute reference for measuring current in the NIST-4 Kibble balance. 
Video Credit: Sean Kelley/NIST

In a brightly lit subterranean lab at the National Institute of Standards and Technology (NIST) sits a room-sized electromechanical machine called the NIST-4 Kibble balance.

The instrument can already measure the mass of objects of roughly 1 kilogram, about as heavy as a quart of milk, as accurately as any device in the world. But now, NIST researchers have further improved their Kibble balance’s performance by adding to it a custom-built device that provides an exact definition of electrical resistance. The device is called the quantum Hall array resistance standard (QHARS), and it consists of a set of several smaller devices that use a quirk of quantum physics to generate extremely precise amounts of electrical resistance. The researchers describe their work in a Nature Communications paper.

Study indicates likely cause of common penis birth-defect

The prevalence of hypospadias has increased by 11.5% in recent decades, making it the most common genital malformation in newborn males.
Photo Credit: Carlo Navarro

An alarming increase in the occurrence of the most common genital malformation in male babies, hypospadias, is likely due to environmental factors, such as toxicant exposure, which alter epigenetic programming in a forming penis. 

That’s according to a new study in Scientific Reports that identified a direct link between hypospadias tissue samples and the presence of epigenetic alterations, or changes to the molecular factors and processes around DNA that determine how genes behave. Conversely, epigenetic alternations were not found in penile tissue samples taken from the foreskin of healthy babies without hypospadias, according to the Washington State University-led analysis. 

The research helps answer long-standing questions surrounding the increased frequency and potential root cause of hypospadias, a birth defect in which the opening of the urethra is located on the underside of the penis instead of the tip. 

Scientists Suggest New Approach to Targeted Treatment of Bacterial Infections

Photo Source: Ural Federal University

It is based on the nanosystem with polyoxometalate

Chemists from the Ural Federal University have proposed a new approach to targeted treatment of affected areas of the human body, in particular, bacterial infections. It is based on a nanosystem, the core of which is polyoxometalate (containing molybdenum and iron). A broad-spectrum antibiotic, tetracycline, is attached to the surface of the polyoxometalate. This approach makes it possible to fight bacteria more effectively by targeting them. The results of the study are published in the journal Inorganics.

"The polyoxometalate ion is a charged nanoparticle that can be used as a base. It is very small - 2.5 nanometers. This allows it to easily penetrate cells and the walls of blood vessels. Drugs and additional substances (vector molecules) can be "planted" on it to help the system reach a specific affected organ. In this case, the drug is distributed less throughout the rest of the body. This reduces side effects, especially of highly toxic drugs," explains Margarita Tonkushina, a Researcher at the Section of Chemical Material Science and the Laboratory of Functional Design of Nanoclusters of Polyoxometalates at UrFU.

Old yellow enzyme helps algae against light stress

Biologist Anja Hemschemeier researches green algae.
Photo Credit: RUB, Marquard

Old yellow enzymes have been known for almost 100 years, but their function for organisms is largely in the dark. A Bochum research team publishes initial findings on microalgae.

Old yellow enzymes, or OYEs for short, from the English Old Yellow Enzymes, were discovered in the 1930s and have been heavily researched since then. Because these biocatalysts - colored yellow by an auxiliary molecule - can carry out reactions that are very valuable for the chemical industry, such as pre-medication or fragrance substances. Although OYEs are found in many organisms, their natural role for these living beings is hardly known - possibly because the scientific focus was on biotechnological use. Researchers around private lecturer Dr. Anja Hemschemeier and Prof. Dr. Thomas Happe from the Ruhr University Bochum now shows that an OYE of the unicellular green algae Chlamydomonas reinhardtii is important for the vegetable unicellular organism to protect itself from light stress. The researchers published their results in the journal "Plant Direct" from 15. Published January 2023.

New study to tackle role of environmental contamination in the growing problem of antibiotic resistance

Photo Credit: Volodymyr Hryshchenko

Environmental factors, including pollution, that might help ‘superbugs’ become resistant to antibiotics is set to be investigated by the University of Surrey. Findings will help address this serious public health problem by identifying trends and emerging areas that require further research.

During this new eighteen-month study, funded by the One Health European Joint Project, Surrey researchers will embark on work to catalogue the evidence of the effects of environmental factors on antibiotic resistance.  

Dr Giovanni Lo Iacono, Senior Lecturer in Biostatistics and Epidemiology at the University of Surrey, said:

“The World Health Organization has declared antimicrobial resistance as one of the top 10 global public health threats facing humanity. The danger of it cannot be underestimated as it limits treatment options for those who need it most and means that certain infections can become uncontrollable.”

Antibiotic resistance, which is a form of wider antimicrobial resistance, is the ability of bacteria to withstand antibiotics and has led to increasing treatment failure for commonplace infections. Misuse and overuse of antibiotics were previously believed to be the sole cause of this threat. However, the role of environmental factors such as contamination of water or soil by antibiotics, potentially impacting the food chain, is now being recognized.

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.