4.5.24 Silvia Cernea Clark 713−348−6728 [email protected].
Chris Stipes 713−348−6778 [email protected].
Is Director, Infectious Disease Preparedness and Response, Administration for Strategic Preparedness and Response, U.S. Department of Health and Human Services (https://aspr.hhs.gov/Pages/Home.aspx).
The HHS Administration for Strategic Preparedness and Response (ASPR) leads the nation’s medical and public health preparedness for, response to, and recovery from disasters and other public health emergencies.
ASPR collaborates with hospitals, healthcare coalitions, biotech firms, community members, state, local, tribal, and territorial governments, and other partners across the country to improve readiness and response capabilities.
Researchers have developed a new method that uses attosecond core-level spectroscopy to capture molecular dynamics in real time.
The mechanisms behind chemical reactions are complex, involving many dynamic processes that affect both the electrons and the nuclei of the involved atoms. Frequently, the strongly coupled electron and nuclear dynamics trigger radiation-less relaxation processes known as conical intersections. These dynamics underpin many significant biological and chemical functions but are notoriously difficult to detect experimentally.
The challenge in studying these dynamics stems from the difficulty of tracing the nuclear and electronic motion simultaneously. Their dynamics are intertwined and occur on ultrafast timescales, which has made capturing the molecular dynamical evolution in real time a major challenge for both physicists and chemists in recent years.
A detailed study of a reaction between a molecular ion and a neutral atom has implications for both atmospheric and interstellar chemistry.
Reactions between ions and neutral atoms or molecules occur in various settings, from planetary atmospheres to plasmas. They are also the driving force behind rich reaction chains at play in the interstellar medium (ISM)—the giant clouds of gas and dust occupying the space between stars. The ISM is cold, highly dilute, and abundant with ionizing radiation [1]. These conditions are usually unfavorable for chemistry. Yet, more than 300 molecular species have been detected in the ISM to date, of which about 80% contain carbon [2]. Now Florian Grussie at the Max Planck Institute for Nuclear Physics (MPIK) in Germany and collaborators report an experimental and theoretical study of an ion–neutral reaction: that between a neutral carbon atom and a molecular ion (HD+), made of a hydrogen and a deuterium (heavy hydrogen) atom [3, 4]. The study’s findings could improve our understanding of the chemistry of the ISM.
Ion–neutral reactions are fundamentally different from those involving only neutral species. Unlike typical neutral–neutral reactions, ion–neutral reactions often do not need to overcome an activation energy barrier and proceed efficiently even if the temperature approaches absolute zero. The reason for this difference is that, in ion–neutral reactions, the ion strongly polarizes the neutral atom or molecule, causing attractive long-range interactions that bring the reactants together.
Hydrogen (H2) is a promising fuel for reducing greenhouse gases, especially if produced by using renewable energy to split water molecules (H2O). But as simple as it may seem to break water into hydrogen and oxygen, the chemistry is complex.
“Many primary atmospheres of those planets will probably be dominated by hydrocarbon compounds and not so much by oxygen-rich gases such as water and carbon dioxide,” said Dr. Thomas Henning.
Can rocky planets form around stars smaller than our Sun, also called low-mass stars? This is what a recent study published in Science hopes to address as a team of international researchers investigated the chemical properties of an exoplanetary system orbiting the star, ISO-Chal 147, which is located approximately 600 light-years from Earth and whose star has a mass of 11 percent of our Sun with age estimates between 1 to 2 million years old. For context, our Sun is approximately 4.5 billion years old. This study holds the potential to help astronomers better understand the formation and evolution of young exoplanetary systems and their potential to host rocky planets.
For the study, the researchers used the Mid-Infrared Instrument (MIRI) on the NASA’s James Webb Space Telescope (JWST) to identify carbon-bearing molecules at temperatures of approximately 30 degrees Celsius (86 degrees Fahrenheit) within the protoplanetary disk forming around the young star. However, the team also found these molecules did not possess compounds containing oxygen, meaning the system might not have water or carbon dioxide, which are typically found in systems surrounding stars like our Sun.
Continue reading “Implications for Rocky Planet Formation Around Low-Mass Stars” »
Yale researchers are using chemical “chameleons” to sneak up on drug-resistant brain tumors.
A Yale Cancer Center team has synthesized a compound, KL-50, that they say selectively targets drug-resistant glioblastomas while leaving healthy tissue alone.
Yale scientists say KL-50, their lead “chameleon” compound, effectively targets tumors without harming healthy surrounding tissue.
Continue reading “This well-timed ‘chameleon’ sneaks up on drug-resistant brain cancers” »
A new study used machine learning to predict potential new antibiotics in the global microbiome, which study authors say marks a significant advance in the use of artificial intelligence in antibiotic resistance research…
For this study, the researchers collected genomes and meta-genomes stored in publicly available databases and looked for DNA snippets that could have antimicrobial activity. To validate those predictions, they used chemistry to synthesize 100 of those molecules in the laboratory and then test them to determine if they could actually kill bacteria, including ‘some of the most dangerous pathogens in our society’, de la Fuente said.
One of Earth’s most consequential bursts of biodiversity—a 30-million-year period of explosive evolutionary changes spawning innumerable new species —may have the most modest of creatures to thank for the vital stage in life’s history: worms.
The digging and burrowing of prehistoric worms and other invertebrates along ocean bottoms sparked a chain of events that released oxygen into the ocean and atmosphere and helped kick-start what is known as the Great Ordovician Biodiversification Event, roughly 480 million years ago, according to new findings Johns Hopkins University researchers published in the journal Geochimica et Cosmochimica Acta.
“It’s really incredible to think how such small animals, ones that don’t even exist today, could alter the course of evolutionary history in such a profound way,” said senior author Maya Gomes, an assistant professor in the Department of Earth and Planetary Sciences. “With this work, we’ll be able to examine the chemistry of early oceans and reinterpret parts of the geological record.”
When element 61, also known as promethium, was first isolated by scientists at the Department of Energy’s Oak Ridge National Laboratory in 1945, it completed the series of chemical elements known as lanthanides. However, aspects of the element’s exact chemical nature have remained a mystery until last year, when a team of scientists from ORNL and the National Institute of Standards and Technology used a combination of experimentation and computer simulation to purify the promethium radionuclide and synthesize a coordination complex that was characterized for the first time. The results of their work were recently published in Nature.
