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Archive for the ‘chemistry’ category: Page 153

Jan 9, 2023

Investigating the intestinal transport of mercury ions with a gut-on-a-chip device

Posted by in categories: biotech/medical, chemistry, engineering, life extension

The transport of mercury ions across intestinal epithelial cells can be studied for toxicology assessments by using animal models and static cell cultures. However, the concepts do not reliably replicate conditions of the human gut microenvironment to monitor in situ cell physiology. As a result, the mechanism of mercury transport in the human intestine is still unknown.

In a new report now published in Nature Microsystems and Nanoengineering, Li Wang and a research team in and in China developed a gut-on-a-chip instrument integrated with transepithelial electrical resistance (TEER) sensors and electrochemical sensors.

They proposed to explore the dynamic concept to simulate the physical intestinal barrier and mirror biological transport and adsorption mechanisms of mercury ions. The scientists recreated the cellular microenvironment by applying fluid shear stress and cyclic mechanical strain.

Jan 9, 2023

Nanoplastics unexpectedly produce reactive oxidizing species when exposed to light

Posted by in categories: chemistry, engineering, particle physics

Plastics are ubiquitous in our society, found in packaging and bottles as well as making up more than 18% of solid waste in landfills. Many of these plastics also make their way into the oceans, where they take up to hundreds of years to break down into pieces that can harm wildlife and the aquatic ecosystem.

A team of researchers, led by Young-Shin Jun, Professor of Energy, Environmental & Chemical Engineering in the McKelvey School of Engineering at Washington University in St. Louis, analyzed how light breaks down polystyrene, a nonbiodegradable plastic from which packing peanuts, DVD cases and disposable utensils are made. In addition, they found that nanoplastic particles can play active roles in environmental systems. In particular, when exposed to light, the nanoplastics derived from polystyrene unexpectedly facilitated the oxidation of aqueous ions and the formation of manganese oxide solids that can affect the fate and transport of organic contaminants in natural and engineering water systems.

The research, published in ACS Nano on Dec. 27, 2022, showed how the photochemical reaction of nanoplastics through light absorption generates peroxyl and superoxide radicals on surfaces, and initiates oxidation of manganese into manganese oxide solids.

Jan 8, 2023

Electrochemistry converts carbon to useful molecules

Posted by in categories: chemistry, innovation

A chemistry collaboration has led to a creative way to put carbon dioxide to good—and even healthy—use: by incorporating it, via electrosynthesis, into a series of organic molecules that are vital to pharmaceutical development.

In the process, the research team made an innovative discovery. By changing the type of electrochemical reactor, they could produce two completely different products, both of which are useful in .

The team’s paper, “Electrochemical Reactor Dictates Site Selectivity in N-Heteroarene Carboxylations,” published Jan 5 in Nature. The paper’s co-lead authors are postdoctoral researchers Peng Yu and Wen Zhang, and Guo-Quan Sun of Sichuan University in China.

Jan 7, 2023

Aging Is Linked to More Activity in Short Genes Than in Long Genes

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

Our DNA is made up of genes that vary drastically in size. In humans, genes can be as short as a few hundred molecules known as bases or as long as two million bases. These genes carry instructions for constructing proteins and other information crucial to keeping the body running. Now a new study suggests that longer genes become less active than shorter genes as we grow older. And understanding this phenomenon could reveal new ways of countering the aging process.

Luís Amaral, a professor of chemical and biological engineering at Northwestern University, says he and his colleagues did not initially set out to examine gene length. Some of Amaral’s collaborators at Northwestern had been trying to pinpoint alterations in gene expression—the process through which the information in a piece of DNA is used to form a functional product, such as a protein or piece of genetic material called RNA—as mice aged. But they were struggling to identify consistent changes. “It seemed like almost everything was random,” Amaral says.

Then, at the suggestion of Thomas Stoeger, a postdoctoral scholar In Amaral’s lab, the team decided to consider shifts in gene length. Prior studies had hinted that there might be such a large-scale change in gene activity with age—showing, for example, that the amount of RNA declines over time and that disruptions to transcription (the process through which RNA copies, or transcripts, are formed from DNA templates) can have a greater impact on longer genes than shorter ones.

Jan 6, 2023

A few-layer covalent network of fullerenes

Posted by in category: chemistry

A two-dimensional crystalline polymer of C60, termed graphullerene, is synthesized by chemical vapour transport, and mechanically exfoliated to produce molecularly thin flakes with clean interfaces for potential optoelectronic applications.

Jan 6, 2023

Geometry of brain, dimensions of mind: Researchers identify new ways to characterize states of consciousness

Posted by in categories: biotech/medical, chemistry, health, neuroscience

What it means to be conscious is more than just a philosophical question. Researchers continue to investigate how conscious experience arises from the electrochemical activity of the human brain. The answer has important implications for the way brain health is understood—from coma, wherein a person is alive but unable to move or respond to his or her environment, to surgical anesthesia, to the altered thought processes of schizophrenia.

Recent research suggests that there’s no one location in the brain that causes consciousness, pointing to a network phenomenon. However, tracing the various linkages between regions in the brain networks that give rise to awareness and wakefulness has been elusive.

A new approach using functional MRI, an imaging technique that allows you to see and measure brain activity through changes in blood flow over time, provides new insight into how we describe and study conscious states.

Jan 5, 2023

New quantum computing architecture could be used to connect large-scale devices

Posted by in categories: chemistry, finance, quantum physics, supercomputing

Quantum computers hold the promise of performing certain tasks that are intractable even on the world’s most powerful supercomputers. In the future, scientists anticipate using quantum computing to emulate materials systems, simulate quantum chemistry, and optimize hard tasks, with impacts potentially spanning finance to pharmaceuticals.

However, realizing this promise requires resilient and extensible hardware. One challenge in building a large-scale quantum computer is that researchers must find an effective way to interconnect quantum nodes—smaller-scale processing nodes separated across a computer chip. Because quantum computers are fundamentally different from classical computers, conventional techniques used to communicate electronic information do not directly translate to quantum devices. However, one requirement is certain: Whether via a classical or a quantum interconnect, the carried information must be transmitted and received.

To this end, MIT researchers have developed a quantum computing architecture that will enable extensible, high-fidelity communication between superconducting quantum processors. In work published in Nature Physics, MIT researchers demonstrate step one, the deterministic emission of single photons—information carriers—in a user-specified direction. Their method ensures quantum information flows in the correct direction more than 96 percent of the time.

Jan 5, 2023

Dr. Stuart Minchin, Ph.D. — Sustainable Pacific Development Through Science, Knowledge & Innovation

Posted by in categories: biological, chemistry, education, food, health, science, sustainability

Is the Director General of the Pacific Community (SPC — https://www.spc.int/about-us/director-general) which is the largest intergovernmental organization in the Pacific and serves as a science and technology for development organization owned by the 26 Member countries and territories in the Pacific region.

SPC’s 650 member staff deliver services and scientific advice to the Pacific across the domains of Oceans, Islands and People, and has deep expertise in food security, water resources, fisheries, disasters, energy, maritime, health, statistics, education, human rights, social development and natural resources.

Continue reading “Dr. Stuart Minchin, Ph.D. — Sustainable Pacific Development Through Science, Knowledge & Innovation” »

Jan 5, 2023

What Are The Odds Of Alien Life? The Drake Equation

Posted by in categories: alien life, chemistry, Elon Musk, information science, mathematics, physics

Commercial Purposes ► Lorenzovareseaziendale@gmail.com.

What is the Drake Equation? We are talking about The Odds of ALIEN LIFE.
Is there life out there in the Universe?
How are the chances to find Extraterrestrial life?

Continue reading “What Are The Odds Of Alien Life? The Drake Equation” »

Jan 5, 2023

The Eccentricities of J. Robert Oppenheimer

Posted by in categories: chemistry, cosmology, military, particle physics, quantum physics

The so-called “Father of the Atomic Bomb” J. Robert Oppenheimer was once described as “a genius of the nuclear age and also the walking, talking conscience of science and civilization”. Born at the outset of the 20th century, his early interests in chemistry and physics would in the 1920s bring him to Göttingen University, where he worked alongside his doctoral supervisor Max Born (1882−1970), close lifelong friend Paul Dirac (1902−84) and eventual adversary Werner Heisenberg (1901−76). This despite the fact that even as early as in his youth, Oppenheimer was singled out as both gifted and odd, at times even unstable. As a child he collected rocks, wrote poetry and studied French literature. Never weighing more than 130 pounds, throughout his life he was a “tall and thin chainsmoker” who once stated that he “needed physics more than friends” who at Cambridge University was nearly charged with attempted murder after leaving a poisoned apple on the desk of one of his tutors. Notoriously abrupt and impatient, at Göttingen his classmates once gave their professor Born an ultimatum: “either the ‘child prodigy’ is reigned in, or his fellow students will boycott the class”. Following the successful defense of his doctoral dissertation, the professor administering the examination, Nobel Laureate James Franck (1882−1964) reportedly left the room stating.

“I’m glad that’s over. He was at the point of questioning me”

From his time as student at Harvard, to becoming a postgraduate researcher in Cambridge and Göttingen, a professor at UC Berkeley, the scientific head of the Manhattan project and after the war, the Director of the Institute for Advanced Study, wherever Oppenheimer went he could hold his own with the greatest minds of his age. Max Born, Paul Dirac, John von Neumann, Niels Bohr, Albert Einstein, Kurt Gödel, Richard Feynman, they all admired “Oppie”. When he died in 1967, his published articles in physics totaled 73, ranging from topics in quantum field theory, particle physics, the theory of cosmic radiations to nuclear physics and cosmology. His funeral was attended by over 600 people, and included numerous associates from academia and research as well as government officials, heads of military, even the director of the New York City Ballet.