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Archive for the ‘chemistry’ category: Page 300

May 11, 2020

Electromagnetic water cloak eliminates drag and wake

Posted by in categories: chemistry, particle physics

Researchers have developed a water cloaking concept based on electromagnetic forces that could eliminate an object’s wake, greatly reducing its drag while simultaneously helping it avoid detection.

The idea originated at Duke University in 2011 when researchers outlined the general concept. By matching the acceleration of the surrounding water to an ’s movement, it would theoretically be possible to greatly increase its propulsion efficiency while leaving the surrounding sea undisturbed. The theory was an extension of the group’s pioneering work in metamaterials, where a material’s structure, rather than its chemistry, creates desired properties.

Six years later, Yaroslav Urzhumov, adjunct assistant professor of electrical and computer engineering at Duke, has updated the theory by detailing a potential approach. But rather than using a complex system of very small pumps as originally speculated, Urzhumov is turning to electromagnetic fields and the dense concentration of charged particles found in saltwater.

May 11, 2020

Revealed: Plants Molecular ‘Alarm’ System That Protects Them From Predators

Posted by in categories: chemistry, military

Scientists uncover how oral secretions of the cotton leaf worm trigger defense responses in a plant.

In nature, every species must be equipped with a strategy to be able to survive in response to danger. Plants, too, have innate systems that are triggered in response to a particular threat, such as insects feeding on them.

For example, some plants sense “herbivore-derived danger signals” (HDS), which are specific chemicals in oral secretions of insects. This activates a cascade of events in the plant’s defense machinery, which leads to the plant developing “resistance” to (or “immunity” against) the predator. But despite decades of research, exactly how plants recognize these signals has remained a bit of a mystery.

May 10, 2020

Reversing age: dual species measurement of epigenetic age with a single clock

Posted by in categories: biotech/medical, chemistry, finance, genetics, life extension, neuroscience

Young blood plasma is known to confer beneficial effects on various organs in mice. However, it was not known whether young plasma rejuvenates cells and tissues at the epigenetic level; whether it alters the epigenetic clock, which is a highly-accurate molecular biomarker of aging. To address this question, we developed and validated six different epigenetic clocks for rat tissues that are based on DNA methylation values derived from n=593 tissue samples. As indicated by their respective names, the rat pan-tissue clock can be applied to DNA methylation profiles from all rat tissues, while the rat brain-, liver-, and blood clocks apply to the corresponding tissue types. We also developed two epigenetic clocks that apply to both human and rat tissues by adding n=850 human tissue samples to the training data. We employed these six clocks to investigate the rejuvenation effects of a plasma fraction treatment in different rat tissues. The treatment more than halved the epigenetic ages of blood, heart, and liver tissue. A less pronounced, but statistically significant, rejuvenation effect could be observed in the hypothalamus. The treatment was accompanied by progressive improvement in the function of these organs as ascertained through numerous biochemical/physiological biomarkers and behavioral responses to assess cognitive functions. Cellular senescence, which is not associated with epigenetic aging, was also considerably reduced in vital organs. Overall, this study demonstrates that a plasma-derived treatment markedly reverses aging according to epigenetic clocks and benchmark biomarkers of aging.

Several authors are founders, owners, employees (Harold Katcher and Akshay Sanghavi) or consultants of Nugenics Research (Steve Horvath and Agnivesh Shrivastava) which plans to commercialize the “Elixir” treatment. Other authors (Kavita Singh, Shraddha Khairnar) received financial support from Nugenics Research. The other authors do not have conflict of interest.

May 8, 2020

Chemistry breakthrough could speed up drug development

Posted by in categories: biotech/medical, chemistry, nanotechnology

Scientists have successfully developed a new technique to reliably grow crystals of organic soluble molecules from nanoscale droplets, unlocking the potential of accelerated new drug development.

Chemistry experts from Newcastle and Durham universities, working in collaboration with SPT Labtech, have grown the small crystals from nanoscale encapsulated droplets. Their innovative method, involving the use of inert oils to control evaporative solvent loss, has the potential to enhance the development pipeline.

Whilst crystallization of organic soluble is a technique used by scientists all over the world, the ability to do so with such small quantities of analyte is ground-breaking.

May 8, 2020

Successfully measuring infinitesimal change in mass of individual atoms for the first time

Posted by in categories: chemistry, mobile phones, particle physics, quantum physics

A new door to the quantum world has been opened: When an atom absorbs or releases energy via the quantum leap of an electron, it becomes heavier or lighter. This can be explained by Einstein’s theory of relativity (E = mc2). However, the effect is minuscule for a single atom. Nevertheless, the team of Klaus Blaum and Sergey Eliseev at the Max Planck Institute for Nuclear Physics has successfully measured this infinitesimal change in the mass of individual atoms for the first time. In order to achieve this, they used the ultra-precise Pentatrap atomic balance at the Institute in Heidelberg. The team discovered a previously unobserved quantum state in rhenium, which could be interesting for future atomic clocks. Above all, this extremely sensitive atomic balance enables a better understanding of the complex quantum world of heavy atoms.

Astonishing, but true: If you wind a mechanical watch, it becomes heavier. The same thing happens when you charge your smartphone. This can be explained by the equivalence of energy (E) and mass (m), which Einstein expressed in the most famous formula in physics: E = mc2 (c: speed of light in vacuum). However, this effect is so small that it completely eludes our everyday experience. A conventional balance would not be able to detect it.

But at the Max Planck Institute for Nuclear Physics in Heidelberg, there is a balance that can: Pentatrap. It can measure the minuscule change in mass of a single atom when an electron absorbs or releases energy via a quantum jump, thus opening a for precision physics. Such quantum jumps in the electron shells of atoms shape our world—whether in life-giving photosynthesis and general chemical reactions or in the creation of colour and our vision.

May 8, 2020

In situ Fabrication of Nano ZnO/BCM Biocomposite Based on MA Modified Bacterial Cellulose Membrane for Antibacterial and Wound Healing

Posted by in categories: biotech/medical, chemistry, nanotechnology

Developing an ideal wound dressing that meets the multiple demands of safe and practical, good biocompatibility, superior mechanical property and excellent antibacterial activity is highly desirable for wound healing. Bacterial cellulose (BC) is one of such promising class of biopolymers since it can control wound exudates and can provide moist environment to a wound resulting in better wound healing. However, the lack of antibacterial activity has limited its application.

We prepared a flexible dressing based on a bacterial cellulose membrane and then modified it by chemical crosslinking to prepare in situ synthesis of nZnO/BCM via a facile and eco-friendly approach. Scanning electron microscopy (SEM) results indicated that nZnO/BCM membranes were characterized by an ideal porous structure (pore size: 30~ 90 μm), forming a unique string-beaded morphology. The average water vapor transmission of nZnO/BCM was 2856.60 g/m2/day, which improved the moist environment of nZnO/BCM. ATR-FITR further confirmed the stepwise deposition of nano-zinc oxide. Tensile testing indicated that our nanocomposites were flexible, comfortable and resilient. Bacterial suspension assay and plate counting methods demonstrated that 5wt. % nZnO/BCM possessed excellent antibacterial activity against S.aureus and E. coli, while MTT assay demonstrated that they had no measurable cytotoxicity toward mammalian cells.

May 8, 2020

Second skin protects against chemical, biological agents

Posted by in categories: biotech/medical, chemistry, military

Recent events such as the COVID-19 pandemic and the use of chemical weapons in the Syria conflict have provided a stark reminder of the plethora of chemical and biological threats that soldiers, medical personnel and first responders face during routine and emergency operations.

Personnel safety relies on which, unfortunately, still leaves much to be desired. For example, high breathability (i.e., the transfer of water vapor from the wearer’s body to the outside world) is critical in protective military uniforms to prevent heat-stress and exhaustion when soldiers are engaged in missions in contaminated environments. The same materials (adsorbents or barrier layers) that provide protection in current garments also detrimentally inhibit breathability.

To tackle these challenges, a multi-institutional team of researchers led by Lawrence Livermore National Laboratory (LLNL) scientist Francesco Fornasiero has developed a smart, breathable fabric designed to protect the wearer against biological and chemical warfare agents. Material of this type could be used in clinical and medical settings as well. The work was recently published online in Advanced Functional Materials and represents the successful completion of Phase I of the project, which is funded by the Defense Threat Reduction Agency through the Dynamic Multifunctional Materials for a Second Skin “D[MS]2” program.

May 8, 2020

Scientists publish data on COVID-19-related proteins

Posted by in categories: chemistry, quantum physics

A group of scientists led by Teruki Honma of the RIKEN Center for Biosystems Dynamics Research and including collaborators from Hoshi University and Mizuho Information & Research Institute have released key data on the proteins associated with the novel coronavirus that causes COVID-19. As a means to facilitate the development of anti-COVID-19 therapeutics, crystal structures of dozens of drug targets including the virus’s main protease, RNA dependent RNA polymerase, and S protein have been published by Protein Data Bank (PDB). The research group has performed ab initio quantum chemical calculations based on the crystal structures using the fragment molecule orbital method, and published the data at FMODB as a database for data acquired using that method. According Honma, “We hope that this data will help scientists quickly develop therapies for this devastating virus. We will continue to perform FMO calculations on newly released protein structures and update our data. This data will be important by allowing an understanding of the precise energy data for interactions between drug candidates and virus proteins.”

The data is available at FMODB: The database of quantum mechanical data based on the FMO methodThe webpage will open in a new tab..

May 8, 2020

Here’s how nanoparticles could help us get closer to a treatment for COVID-19

Posted by in categories: biotech/medical, chemistry, nanotechnology

There is no vaccine or specific treatment for COVID-19, the disease caused by the severe acute respiratory syndrome coronavirus 2, or SARS-CoV-2.

Since the outbreak began in late 2019, researchers have been racing to learn more about SARS-CoV-2, which is a strain from a family of viruses known as coronavirus for their crown-like shape.


Northeastern chemical engineering professor Thomas Webster, who specializes in developing nano-scale medicine and technology to treat diseases, is part of a contingency of scientists that are contributing ideas and technology to the Centers for Disease Control and Prevention to fight the COVID-19 outbreak.

Continue reading “Here’s how nanoparticles could help us get closer to a treatment for COVID-19” »

May 7, 2020

Quantum resonances near absolute zero

Posted by in categories: chemistry, energy, quantum physics

Recently, Prof. Yang Xueming from the Dalian Institute of Chemical Physics of the Chinese Academy of Sciences and Prof. Yang Tiangang from the Southern University of Science and Technology discussed significant advances in the study of quantum resonances in atomic and molecular collisions at near absolute zero temperature. Their article was published in Science on May 7.

The rules of quantum mechanics govern all atomic and molecular processes. Understanding the quantum nature of atomic and is essential for understanding energy transfer and chemical reaction processes, especially in the low collisional energy region, where quantum effect is the most prominent.

A remarkable feature of quantum nature in atomic and molecular collision is quantum scattering resonances, but probing them experimentally has been a great challenge due to the transient nature of these resonances.