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Scientists refer to this phenomenon as the Great Oxidation Event, or GOE for short. But the initial accumulation of O2 on Earth was not nearly as straightforward as that moniker suggests, according to new research led by a University of Utah geochemist.

This “event” lasted at least 200 million years. And tracking the accumulation of O2 in the oceans has been very difficult until now, said Chadlin Ostrander, an assistant professor in the Department of Geology and Geophysics.

“Emerging data suggest that the initial rise of O2 in Earth’s atmosphere was dynamic, unfolding in fits-and-starts until perhaps 2.2. billion years ago,” said Ostrander, lead author on the study published June 12 in the journal Nature. “Our data validate this hypothesis, even going one step further by extending these dynamics to the ocean.”

Most of the universe is invisible to the human eye. The building blocks of stars are only revealed in wavelengths that are outside of the visible spectrum. Astronomers recently used two very different, and very powerful, telescopes to discover twin disks—and twin parallel jets—erupting from young stars in a multiple star system.

This discovery was unexpected, and unprecedented, given the age, size, and chemical makeup of the stars, disks, and jets. Their location in a known, well-studied part of the universe adds to the thrill.

Observations from the U.S. National Science Foundation’s (NSF) National Radio Astronomy Observatory’s (NRAO) Atacama Large Millimeter/submillimeter Array (ALMA) and NASA’s James Webb Space Telescope’s (JWST) Mid-Infrared Instrument (MIRI) were combined for this research.

Promethium, one of the rarest and most mysterious elements in the periodic table, has finally given up some crucial chemical secrets.

By Mark Peplow & Nature magazine

One of the rarest and most mysterious elements in the periodic table has finally given up some crucial chemical secrets, eight decades after its discovery. Researchers at Oak Ridge National Laboratory in Tennessee have become the first to use radioactive promethium to make a chemical ‘complex’ — a compound in which it is bound to a few surrounding molecules. This feat of synthesis enabled the team to study how the element bonds with other atoms in a solution with water. Published May 22 in Nature the findings fill a long-standing gap in chemistry textbooks, and could eventually lead to better methods for separating promethium from similar elements in nuclear waste, for example.

In relationships, sharing closer spaces naturally deepens the connection as bonds form and strengthen through increasing shared memories. This principle applies not only to human interactions but also to engineering. Recently, an intriguing study was published demonstrating the use of quantum dots to create metasurfaces, enabling two objects to exist in the same space.

Professor Junsuk Rho from the Department of Mechanical Engineering, the Department of Chemical Engineering, and the Department of Electrical Engineering, PhD candidates Minsu Jeong, Byoungsu Ko, and Jaekyung Kim from the Department of Mechanical Engineering, and Chunghwan Jung, a PhD candidate, from the Department of Chemical Engineering at Pohang University of Science and Technology (POSTECH) employed Nanoimprint Lithography (NIL) to fabricate metasurfaces embedded with quantum dots, enhancing their luminescence efficiency. Their research was recently published in Nano Letters (“Printable Light-Emitting Metasurfaces with Enhanced Directional Photoluminescence”).

(Left) Schematic diagram of the fabrication of a luminescence-controlled metasurface using the nanoimprint lithography process. (Right) Experiment evaluating the performance of the metasurface’s luminescence control. (Image: POSTECH)

From Rice University

4.5.24 Silvia Cernea Clark 713−348−6728 [email protected].

Chris Stipes 713−348−6778 [email protected].

If you were to throw a message in a bottle into a black hole, all of the information in it, down to the quantum level, would become completely scrambled. Because in black holes this scrambling happens as quickly and thoroughly as quantum mechanics allows, they are generally considered nature’s ultimate information scramblers.

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.

Dr. Boucher previously held several other critical roles in the organization, including as Chief of the Antivirals \& Antitoxins branch at BARDA’s Anthrax, Botulinum, Ebola and Smallpox therapeutics program office, Acting Director for the Administration for Strategic Preparedness and Response’s Office of Industrial Base Management and Supply Chain (IBM/SC) and serving as HHS’s lead negotiator for product development/procurement agreements for COVID-19 medical countermeasures.

Dr. Boucher has a Bachelor of Science (B.S.), Genetics, and a Doctor of Philosophy (PhD), Biochemistry and Molecular Biology from University of California, Davis.

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.