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Archive for the ‘chemistry’ category: Page 22

Mar 21, 2024

Tiny magnetic implants enable wireless health monitoring when paired with wearable device

Posted by in categories: chemistry, computing, health, wearables

In a study published in the journal Science Advances, researchers from Peking University have unveiled a miniaturized implantable sensor capable of health monitoring without the need of transcutaneous wires, integrated circuit chips, or bulky readout equipment, thereby reducing infection risks, improving biocompatibility, and enhancing portability. The study is titled “Millimeter-scale magnetic implants paired with a fully integrated wearable device for wireless biophysical and biochemical sensing.”

Mar 20, 2024

China Room Temperature Superconductor Researcher Had Experiments to Refute Critics

Posted by in categories: chemistry, materials

Chinese researchers are making variations of LK99 room temperature superconductor materials with more sulfur and copper in the chemistry. They are publishing results with stronger magnetic indications of a Meissner effect.

The chinese researchers have been online discussing their room temperature superconducting research and the challenges of the materials.

Here are the issues discussed.

Mar 20, 2024

Can epigenetic reprogramming reverse aging?

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

The field of aging research has made significant progress over the last three decades, reaching a stage where we now understand the underlying mechanisms of the aging process. Moreover, the knowledge has broadened to include techniques that quantify aging, decelerate its process, as well as sometimes reverse aging.

To date, twelve hallmarks of aging have been identified; these include reduced mitochondrial function, loss of stem cells, increased cellular senescence, telomere shortening, and impaired protein and energy homeostasis. Biomarkers of aging help to understand age-related changes, track the physiological aging process and predict age-related diseases [1].

Longevity. Technology: Biological information is stored in two main ways, the genomes consisting of nucleic acids, and the epigenome, consisting of chemical modifications to the DNA as well as histone proteins. However, biological information can be lost over time as well as disrupted due to cell damage. How can this loss be overcome? In the 1940s, American mathematician and communications engineer Claude Shannon came up with a neat solution to prevent the loss of information in communications, introducing an ‘observer’ that would help to ensure that the original information survives and is transmitted [2]. Can these ideas be applied to aging?

Mar 19, 2024

New study uncovers how hydrogen provided energy at life’s origin

Posted by in categories: biological, chemistry, sustainability

Hydrogen gas is a clean fuel. It burns with oxygen in the air to provide energy with no CO2. Hydrogen is a key to sustainable energy for the future. Though humans are just now coming to realize the benefits of hydrogen gas (H2 in chemical shorthand), microbes have known that H2 is a good fuel for as long as there has been life on Earth. Hydrogen is ancient energy.

Mar 19, 2024

Scientists Develop Groundbreaking Sensor That Can Wirelessly Detect Chemical Warfare Agents

Posted by in categories: chemistry, energy, military

Researchers have developed a revolutionary sensor capable of detecting chemical warfare agents without wires, representing a major advancement in technology for public safety. This innovative device, capable of identifying substances like dimethyl methylphosphonate (DMMP), offers a new level of efficiency and reliability in monitoring and responding to chemical threats, without the need for direct power sources or physical connections.

The urgent need for advanced detection of chemical warfare agents (CWAs) to ensure global security has led to the development of a novel gas sensor. This sensor is distinguished by its rapid response, high sensitivity, and compact size, crucial for the early detection of CWAs. Accurate detection and monitoring of CWAs are vital for effective defense operations, both military and civilian. Due to the hazardous nature of CWAs, research is typically limited to authorized laboratories using simulants that mimic CWAs’ chemical structure without their toxic effects.

Mar 19, 2024

NIO Switches Its Standard 75-kWh Battery From Hybrid-Cell LFP/NCM To All-LFP

Posted by in categories: chemistry, transportation

NIO’s entry-level Standard battery pack option will soon get an upgrade with the new 2024 model year cars.

According to the company (via CnEVPost), the 75-kilowatt-hour dual-chemistry (LFP/NCM) Standard battery will be replaced by a new 75-kWh battery with only LFP battery cells. This should simplify the pack and reduce costs. LFP’s battery cell chemistry is known as one of the least expensive per kWh.

Mar 19, 2024

New Phospholipid Discovery Rewrites the Story of the Origin of Life

Posted by in categories: chemistry, evolution

Approximately 4 billion years ago, Earth was in the process of creating conditions suitable for life. Origin-of-life scientists often wonder if the type of chemistry found on the early Earth was similar to what life requires today. They know that spherical collections of fats, called protocells, were the precursor to cells during this emergence of life. But how did simple protocells first arise and diversify to eventually lead to life on Earth?

Now, Scripps Research scientists have discovered one plausible pathway for how protocells may have first formed and chemically progressed to allow for a diversity of functions.

Continue reading “New Phospholipid Discovery Rewrites the Story of the Origin of Life” »

Mar 19, 2024

Cage escape governs photoredox reaction rates and quantum yields

Posted by in categories: chemistry, quantum physics

The 3 MLCT-excited [Ru(bpz)3]2+ and the spin-flip excited states of [Cr(dqp)2]3+ underwent photoinduced electron-transfer reactions with 12 amine-based electron donors similarly well, but provided cage escape quantum yields differing by up to an order of magnitude. In three exemplary benchmark photoredox reactions performed with different electron donors, the differences in the reaction rates observed when using either [Ru(bpz)3]2+ or [Cr(dqp)2]3+ as photocatalyst correlated with the magnitude of the cage escape quantum yields. These correlations indicate that the cage escape quantum yields play a decisive role in the reaction rates and quantum efficiencies of the photoredox reactions, and also illustrate that luminescence quenching experiments are insufficient for obtaining quantitative insights into photoredox reactivity.

From a purely physical chemistry perspective, these findings are not a priori surprising as the rate of photoproduct formation in an overall reaction comprising several consecutive elementary steps can be expressed as the product of the quantum yields of the individual elementary steps45,46. A recent report on solvent-dependent cage escape and photoredox studies suggested that the correlations between photoredox product formation rates and cage escape quantum yields might be observable11, but we are unaware of previous reports that have been able to demonstrate that the rate of product formation in several batch-type photoreactions correlates with the cage escape quantum yields determined from laser experiments. Synthetic photochemistry and mechanistic investigations are often conducted under substantially different conditions, which can lead to controversial discrepancies47,48,49, whereas here their mutual agreement seems remarkable, particularly given the complexity of the overall reactions.

The available data and the presented analysis suggest that the different cage escape behaviours of [Ru(bpz)3]2+ and [Cr(dqp)2]3+ originate in the fact that for any given electron donor, in-cage reverse electron transfer is ~0.3 eV more exergonic for the RuII complex than for the CrIII complex. Thermal reverse electron transfer between caged radical pairs therefore occurs more deeply in the Marcus inverted region with [Ru(bpz)3]2+ than with [Cr(dqp)2]3+, decelerating in-cage charge recombination in the RuII complex and increasing the cage escape quantum yields compared with the CrIII complex (Fig. 3D).

Mar 19, 2024

How Fear Unfolds inside Our Brains

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

The stress-induced mechanisms that cause our brain to produce feelings of fear in the absence of threats have been mostly a mystery. Now, neurobiologists at the University of California San Diego have identified the changes in brain biochemistry and mapped the neural circuitry that cause such a generalized fear experience. Their research, published in the journal Science on March 15, 2024, provides new insights into how fear responses could be prevented.

In their report, former UC San Diego Assistant Project Scientist Hui-quan Li, (now a senior scientist at Neurocrine Biosciences), Atkinson Family Distinguished Professor Nick Spitzer of the School of Biological Sciences and their colleagues describe the research behind their discovery of the neurotransmitters — the chemical messengers that allow the brain’s neurons to communicate with one another — at the root of stress-induced generalized fear.

Studying the brains of mice in an area known as the dorsal raphe (located in the brainstem), the researchers found that acute stress induced a switch in the chemical signals in the neurons, flipping from excitatory “glutamate” to inhibitory “GABA” neurotransmitters, which led to generalized fear responses.

Mar 18, 2024

Mimicking exercise with a pill

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

NEW ORLEANS, March 18, 2024 — Doctors have long prescribed exercise to improve and protect health. In the future, a pill may offer some of the same benefits as exercise. Now, researchers report on new compounds that appear capable of mimicking the physical boost of working out — at least within rodent cells. This discovery could lead to a new way to treat muscle atrophy and other medical conditions in people, including heart failure and neurodegenerative disease.

The researchers will present their results today at the spring meeting of the American Chemical Society (ACS). ACS Spring 2024 is a hybrid meeting being held virtually and in person March 17–21; it features nearly 12,000 presentations on a range of science topics.

Continue reading “Mimicking exercise with a pill” »

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