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Mar 21, 2024

Scientists Find ‘Switch’ That Stops Immune System Attacking Healthy Cells

Posted by in categories: biotech/medical, chemistry

Our immune system is talented at telling the difference between the chemistry of our own body and that of an invading pathogen. When it malfunctions, our body can become host to an intense civil war.

Scientists are keen to understand this in more detail, and a newly identified ‘switch’ that deactivates a sensor of foreign DNA may provide important insight.

A key part of this discovery, made by a team from the Swiss Federal Institute of Technology Lausanne, is an enzyme called cyclic GMP-AMP synthase (cGAS).

Mar 21, 2024

Two ancient threads discovered in Milky Way galaxy named Shiva and Shakti

Posted by in categories: chemistry, space

Khyati Malhan of the Max Planck Institute for Astronomy (MPIA) in Heidelberg, Germany, who spearheaded the research, expressed astonishment at the ability to detect these ancient structures.

“The Milky Way has undergone profound changes since these stars were born. The fact that we can still recognize them as a group is truly amazing and a testament to the unprecedented data provided by Gaia,” Malhan stated.

The discovery was made possible through Gaia’s observations, which allowed researchers to determine the orbits, content, and composition of individual stars within the Milky Way. “Upon visualising the orbits of these stars, two new structures emerged, distinguished by their unique chemical composition. We named them Shakti and Shiva,” added Malhan.

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).

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