From University of New South Wales: “‘When chemistry became biology’: looking for the origins of life in hot springs”

From University of New South Wales

05 May 2020

Sherry Landow
UNSW Media & Content
02 9385 9555
s.landow@unsw.edu.au

Hot springs may have been the ‘spark’ that helped organic matter turn into life – these UNSW Sydney scientists have put this hypothesis to the test in New Zealand.

Hot springs in New Zealand took Dr Anna Wang and Mr Luke Steller a step closer to the complex geological processes that happened on early Earth. Image: ABC Catalyst.

50 years ago, a meteorite landed in Victoria carrying many of the building blocks for life, including amino acids, nucleobases and lipids. These organic molecules formed when compounds in stardust, which had collected on the meteorite, reacted under low temperatures and UV light as it passed through space.

Many astrobiologists think life on Earth could have been kickstarted when meteorites carrying similar organic matter fell to the planet around four billion years ago.

The big question is how this organic matter along with what was already on Earth – called prebiotic ‘soup’ – turned into life.

“We think hot springs on the Earth’s surface hold the answer,” says Mr Luke Steller, PhD candidate at UNSW’s Australian Centre for Astrobiology. “Their elevated temperature and exposure to the atmosphere allow for a unique process that underwater environments don’t offer.

“The cycle of dehydration (by evaporation) and rehydration (by splashing from geysers or pools) in hot springs allows small lipid bubbles called ‘vesicles’ to form around molecules.

“Vesicles containing the right genetic material could have conceivably been ‘protocells’ – the ancestors of modern living cells.”

Mr Steller is currently collaborating with Dr Anna Wang, Scientia Fellow in the School of Chemistry, to trace when – and how – chemistry became biology.

Late last year, Mr Steller and Dr Wang travelled to Rotorua in New Zealand with ABC Catalyst to recreate this protocell formation in a real hot spring environment. The Catalyst episode, ‘Asteroid Hunters’, airs tonight.

“Almost any sort of chemical reaction could happen in a hot spring,” says Dr Wang.

“If you combine that with the extra-terrestrial material bombarding the planet four billion years ago, they become the most chemically-exciting places on Earth.”

It starts with a bubble

Vesicles, also known as lipid membranes, play a vital role in protecting the genetic molecules in our cells and, potentially, the ancestors to all cells.

“A bubble around some molecules is the first step towards an individual organism,” says Mr Steller. “This entity, a protocell, could be capable of competing with other protocells and start undergoing Darwinian evolution.

“Without a barrier, there is nothing to separate the genetic material from anything else – it would be dilute and part of a homogeneous soup.”

The researchers were inspired by the efforts of Prof David Deamer and Dr Bruce Damer from the University of California, Santa Cruz, to test vesicle formation in a real-world lab.

Mr Steller and Dr Wang prepared vials of lipids (fatty acids) like those found in meteorites and RNA – a nucleic acid essential for life. RNA is theorised to have been present in early Earth.

Combined with hot spring water (containing dissolved minerals and salts), this mixture is an example of a prebiotic soup that might have led to the first replicating cell.

“When we first mixed the prebiotic soup with the hot spring water and submerged the vials into a hot spring, the high temperatures dried out the ingredients,” says Mr Steller. “This process of drying down the lipids and RNA together ‘trapped’ the concentrated RNA between the lipid layers.”

When the soup was rehydrated – a process that occurs naturally in hot springs by splashing – the researchers saw vesicles containing concentrated RNA form.

“By having these wet-dry cycles, all the important organic molecules floating around gets crammed inside one little place. This can help the molecules interact and chemically react.

“Being compartmentalised, these vesicles suddenly have their own ‘identities’ and can start competing, increasing in complexity and evolving towards something life-like.”

Hot springs in Rotorua, New Zealand. Image: ABC Catalyst.

A messy laboratory

Hot springs take astrobiologists a step closer to the complex geological processes that happened on early Earth.

“Early Earth was a messy place,” says Mr Steller. “There were many different minerals and water chemistries present, and clays bubbling around in hot spring pools.

“There was a lot of splashing, lightning and different fluids and gases all getting churned up, boiled and mixed around.”

Travelling to Rotorua offered an opportunity for the researchers to ‘ground-proof’ experiments and show that concepts demonstrated in the lab are robust enough to stay true in messier environments.

“Conducting prebiotic experiments in clean glass test tubes doesn’t really represent what happened on early Earth,” says Mr Steller.

“While we can’t go back in time, we have geological evidence that hot springs were present on early Earth. In some ways, visiting hot springs feels like going back to the source.”

The building blocks of life

Dr Wang is fascinated by the first self-assembly step to life on Earth: where chemicals were able to come together and transition into biology.

She recently received a prestigious $1.7m international life science grant to create self-propagating synthetic cells.

“In origin of life studies, we ask questions like: ‘What physics were necessary for self-assembly?’, ‘What was the geological context that could have helped all those processes?’, and ‘What help did we get from outer space that could have helped catalyse this life?’

“All of these factors came together once – and it was so successful that it was able to persist through billions of years and evolve into all of life that we see today.

“There is shared chemistry to plants, viruses, bacteria, and us. Understanding how it all came about could help us build better microreactors for manufacturing biological goods, or to identify potential drug targets for disease.”

Mr Steller is part of a wider team at UNSW assisting NASA in understanding how life may have been preserved on other planets in our solar system.

“The origin of life is part of humanity’s narrative,” he says.

“Learning more about it isn’t only beneficial for science, it’s helping us develop our understanding of who we are and our place in the universe.”

See the full article here .

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Welcome to UNSW Australia (The University of New South Wales), one of Australia’s leading research and teaching universities. At UNSW, we take pride in the broad range and high quality of our teaching programs. Our teaching gains strength and currency from our research activities, strong industry links and our international nature; UNSW has a strong regional and global engagement.

In developing new ideas and promoting lasting knowledge we are creating an academic environment where outstanding students and scholars from around the world can be inspired to excel in their programs of study and research. Partnerships with both local and global communities allow UNSW to share knowledge, debate and research outcomes. UNSW’s public events include concert performances, open days and public forums on issues such as the environment, healthcare and global politics. We encourage you to explore the UNSW website so you can find out more about what we do.

From University of Maryland: “Maryland Engineers Open Door to Big New Library of Tiny Nanoparticles”

From University of Maryland

April 24, 2020

The development of bimetallic nanoparticles (i.e., tiny particles composed of two different metals that exhibit several new and improved properties) represents a novel area of research with a wide range of potential applications. Now, a research team in the University of Maryland (UMD)’s Department of Materials Science and Engineering (MSE) has developed a new method for mixing metals generally known to be immiscible, or unmixable, at the nanoscale to create a new range of bimetallic materials. Such a library will be useful for studying the role of these bimetallic particles in various reaction scenarios such as the transformation of carbon dioxide to fuel and chemicals.

The study, led by MSE Professor Liangbing Hu, was published in Science Advances on April 24, 2020. Chunpeng Yang, an MSE Research Associate, served as first author on the study.

“With this method, we can quickly develop different bimetallics using various elements, but with the same structure and morphology,” said Hu. “Then we can use them to screen catalytic materials for a reaction; such materials will not be limited by synthesizing difficulties.”

The complex nature of nanostructured bimetallic particles makes mixing such particles difficult, for a variety of reasons—including the chemical makeup of the metals, particle size, and how metals arrange themselves at the nanoscale—using conventional methods.

This new non-equilibrium synthesis method exposes copper-based mixes to a thermal shock of approximately 1300 ̊ Celsius for .02 seconds and then rapidly cools them to room temperature. The goal of using such a short interval of thermal heat is to quickly trap, or ‘freeze,’ the high-temperature metal atoms at room temperature while maintaining their mixing state. In doing so, the research team was able to prepare a collection of homogeneous copper-based alloys. Typically, copper only mixes with a few other metals, such as zinc and palladium—but by using this new method, the team broadened the miscible range to include copper with nickel, iron, and silver, as well.

“Using a scanning electron microscope (SEM) and transmission electron microscope (TEM), we were able to confirm the morphology – how the materials formed – and size of the resulting Cu-Ag [copper-silver] bimetallic nanoparticles,” Yang said.

This method will enable scientists to create more diverse nanoparticle systems, structures, and materials having applications in catalysis, biological applications, optical applications, and magnetic materials.

As a model system for rapid catalyst development, the team investigated copper-based alloys as catalysts for carbon monoxide reduction reactions, in collaboration with Feng Jiao, a professor in the Department of Chemical and Biomolecular Engineering at the University of Delaware. The electro-catalysis of carbon monoxide reduction (COR) is an attractive platform, allowing scientists to use greenhouse gas and renewable electrical energy to produce fuels and chemicals.

“Copper is, thus far, the most promising monometallic electrocatalyst that drives carbon monoxide reduction to value-added chemicals,” said Jiao. “The ability to rapidly synthesize a wide variety of copper-based bimetallic nanoalloys with a uniform structure enables us to conduct fundamental studies on the structure-property relationship in COR and other catalyst systems.”

This non-equilibrium synthetic strategy can be extended to other bimetallic or metal oxide systems, too. Utilizing artificial intelligence-based machine learning, the method will make rapid catalyst screening and rational design possible.

See the full article here .

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Driven by the pursuit of excellence, the University of Maryland has enjoyed a remarkable rise in accomplishment and reputation over the past two decades. By any measure, Maryland is now one of the nation’s preeminent public research universities and on a path to become one of the world’s best. To fulfill this promise, we must capitalize on our momentum, fully exploit our competitive advantages, and pursue ambitious goals with great discipline and entrepreneurial spirit. This promise is within reach. This strategic plan is our working agenda.

The plan is comprehensive, bold, and action oriented. It sets forth a vision of the University as an institution unmatched in its capacity to attract talent, address the most important issues of our time, and produce the leaders of tomorrow. The plan will guide the investment of our human and material resources as we strengthen our undergraduate and graduate programs and expand research, outreach and partnerships, become a truly international center, and enhance our surrounding community.

Our success will benefit Maryland in the near and long term, strengthen the State’s competitive capacity in a challenging and changing environment and enrich the economic, social and cultural life of the region. We will be a catalyst for progress, the State’s most valuable asset, and an indispensable contributor to the nation’s well-being. Achieving the goals of Transforming Maryland requires broad-based and sustained support from our extended community. We ask our stakeholders to join with us to make the University an institution of world-class quality with world-wide reach and unparalleled impact as it serves the people and the state of Maryland.

From Brookhaven National Lab: “New Cathode Material Locks In Oxygen”

From Brookhaven National Lab

April 22, 2020
Stephanie Kossman
skossman@bnl.gov

Scientists synthesized an energy-dense cathode material that has a continuous gradient of lithium concentration, preventing battery failure from oxygen release.

NSLS-II scientists Adrian Hunt (left) and Iradwikanari Waluyo (right) at the IOS beamline, where part of the research was conducted.

From smartphones to electric vehicles, lithium-ion batteries power some of the newest and most prevalent technologies in society. That’s why scientists are working to make these batteries more powerful, more reliable, and longer lasting via new cathode materials.

Choosing more energy-dense materials to build a cathode can solve some of the current challenges, but it often comes with a trade-off, such as gaining battery power in exchange for stability. But now, researchers at the Massachusetts Institute of Technology (MIT) have synthesized a new, energy-dense cathode material for lithium-ion batteries that also solves stability issues. They teamed up with scientists at the National Synchrotron Light Source II (NSLS-II) [below] and used facilities at the Center for Functional Nanomaterials (CFN) [below]—two U.S. Department of Energy (DOE) Office of Science User Facilities at DOE’s Brookhaven National Laboratory—to study chemical changes in the battery over time. The collaboration’s work is published in Nature Energy.

“As you cycle lithium-ion batteries, they can change shape and start to fracture. All kinds of problems can arise that negatively impact how the battery functions,” said co-author Adrian Hunt, a scientist at the In situ and Operando Soft X-ray Spectroscopy (IOS) beamline at NSLS-II, where part of the research was conducted. “One of the causes of these problems is that cathode materials lose oxygen content near the surface. Our collaborators at MIT synthesized a material that locks in the structure of the cathode and its oxygen atoms, preventing the material from expanding and contracting.”

Using molten salt materials and a novel synthesis method, the researchers at MIT developed a cathode with a continuous gradient of lithium in which the concentration is far greater at the material’s core, or “bulk,” than at its surface.

“Traditional cathode materials have a uniform concentration of lithium from the surface through the bulk of the material, so, as the battery operates, oxygen is free to migrate to the surface and, eventually, it gets released, causing the battery to fail,” said co-author Iradwikanari Waluyo, lead beamline scientist at IOS. “The new cathode material, which is lithium-rich towards the bulk and less concentrated at the surface, essentially creates a shell that locks in oxygen, so it doesn’t migrate to the surface and it doesn’t get released.”

Beyond having different concentrations of lithium at the surface and the bulk, a key part of this material’s successful design is the continuous gradient of lithium in between.

“Typically, materials are not continuous,” Hunt said. “If you look down at a very small scale, there will be little grains between sections of the material where the atomic structure is slightly mismatched—like cracks in the material. Those places are problematic for conducting electricity and they also allow for oxygen movement.”

Before the scientists at MIT could understand exactly how their new material was functioning, they needed to bring it to the IOS beamline at NSLS-II, where Waluyo and Hunt used ultrabright “soft” x-rays to reveal the chemical state of the battery in detail. Compared to hard x-rays, which are useful for penetrating heavy elements like metals, soft x-rays can detect lighter elements like oxygen and are more sensitive to their chemical states.

“In addition to detecting oxygen, soft x-rays were critical for studying the different elemental concentrations and chemical states in the material from its surface to its bulk,” Waluyo said. “We can use different detection methods at IOS to tune the sensitivity of the technique to be surface sensitive or bulk sensitive. By looking at the electrons coming out of the sample we can study the surface, and by looking at the photons coming out the sample we can study the bulk.”

IOS is also equipped with a silicon drift detector, which enables researchers at the beamline to differentiate between photons coming from specific elements in the sample. This increases the elemental sensitivity of the technique and eliminates distortions in the data.

“You would not be able to do these kinds of measurements at a standard soft x-ray beamline,” Hunt said. “Most beamlines collect all the photons that come from the sample and you can’t tell the difference between them.”

In addition to NSLS-II, the researchers also leveraged one of the seven facilities at the Center for Functional Nanomaterials (CFN), another DOE Office of Science User Facility at Brookhaven Lab. CFN’s electron microscopy (EM) facility helped the scientists understand the lithium elemental gradient profile across the novel cathode particles.

“The researchers used our operando scanning transmission electron microscope—one of five state-of-the-art transmission electron microscopes in our EM facility,” said Kim Kisslinger, an advanced technical associate at CFN. “This particular microscope is equipped with the capability to perform electron energy loss spectroscopy, which offers high energy resolution and high precision for elemental mapping.”

Moving forward, the researchers at MIT are continuing to collaborate with Waluyo and Hunt at NSLS-II’s IOS beamline.

“They’re experts in making new materials,” Waluyo said. “They make a material and they know it works, but then we come in and show why it works. We look forward to our next experiment together.”

“We are thrilled to work with the exceptional staff at Brookhaven National Laboratory and at the state-of-the-art IOS beamline at NSLS-II,” said MIT’s Ju Li, corresponding author of the paper. “The exciting discoveries today would not be possible without them, and we look forward to much more collaborative work in the future.”

This study was supported in part by the National Science Foundation. Operations at NSLS-II and CFN are supported by DOE’s Office of Science.

See the full article here .

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Brookhaven campus

BNL Center for Functional Nanomaterials

BNL NSLS-II

BNL NSLS II

BNL RHIC Campus

BNL/RHIC Star Detector

BNL Phenix Detector

One of ten national laboratories overseen and primarily funded by the Office of Science of the U.S. Department of Energy (DOE), Brookhaven National Laboratory conducts research in the physical, biomedical, and environmental sciences, as well as in energy technologies and national security. Brookhaven Lab also builds and operates major scientific facilities available to university, industry and government researchers. The Laboratory’s almost 3,000 scientists, engineers, and support staff are joined each year by more than 5,000 visiting researchers from around the world. Brookhaven is operated and managed for DOE’s Office of Science by Brookhaven Science Associates, a limited-liability company founded by Stony Brook University, the largest academic user of Laboratory facilities, and Battelle, a nonprofit, applied science and technology organization.

From Cornell Chronicle: “Researchers use ‘hot Jupiter’ data to mine exoplanet chemistry”

From Cornell Chronicle

April 23, 2020
Blaine Friedlander
bpf2@cornell.edu

Atmospheric gases recede from a “hot Jupiter,” which is a Jupiter-size, egg-shaped planet that orbits close to its own sun, in this artistic rendering. Cornell astronomers have developed a new mathematical model for determining temperatures on different parts of exoplanets, rather than averaging a planet’s temperature. Matthew Fondeur/Cornell University

After spotting a curious pattern in scientific papers – they described exoplanets as being cooler than expected – Cornell astronomers have improved a mathematical model to accurately gauge the temperatures of planets from solar systems hundreds of light-years away.

This new model allows scientists to gather data on an exoplanet’s molecular chemistry and gain insight on the cosmos’ planetary beginnings, according to research published April 23 in Astrophysical Journal Letters.

Nikole Lewis, assistant professor of astronomy and the deputy director of the Carl Sagan Institute (CSI), had noticed that over the past five years, scientific papers described exoplanets as being much cooler than predicted by theoretical models.

“It seemed to be a trend – a new phenomenon,” Lewis said. “The exoplanets were consistently colder than scientists would expect.”

To date, astronomers have detected more than 4,100 exoplanets. Among them are “hot Jupiters,” a common type of gaseous giant that always orbits close to its host star. Thanks to the star’s overwhelming gravity, hot Jupiters always have one side facing their star, a situation known as “tidal locking.”

Therefore, as one side of the hot Jupiter broils, the planet’s far side features much cooler temperatures. In fact, the hot side of the tidally locked exoplanet bulges like a balloon, shaping it like an egg.

From a distance of tens to hundreds of light-years away, astronomers have traditionally seen the exoplanet’s temperature as homogenous – averaging the temperature – making it seem much colder than physics would dictate.

Temperatures on exoplanets – particularly hot Jupiters – can vary by thousands of degrees, according to lead author Ryan MacDonald, a researcher at CSI, who said wide-ranging temperatures can promote radically different chemistry on different sides of the planets.

After poring over exoplanet scientific papers, Lewis, MacDonald and research associate Jayesh Goyal solved the mystery of seemingly cooler temperatures: Astronomers’ math was wrong.

“When you treat a planet in only one dimension, you see a planet’s properties – such as temperature – incorrectly,” Lewis said. “You end up with biases. We knew the 1,000-degree differences were not correct, but we didn’t have a better tool. Now, we do.”

Astronomers now may confidently size up exoplanets’ molecules.

“We won’t be able to travel to these exoplanets any time in the next few centuries, so scientists must rely on models,” MacDonald said, explaining that when the next generation of space telescopes get launched starting in 2021, the detail of exoplanet datasets will have improved to the point where scientists can test the predictions of these three-dimensional models.

“We thought we would have to wait for the new space telescopes to launch,” said MacDonald, “but our new models suggest the data we already have – from the Hubble Space Telescope – can already provide valuable clues.”

With updated models that incorporate current exoplanet data, astronomers can tease out the temperatures on all sides of an exoplanet and better determine the planet’s chemical composition.

Said MacDonald: “When these next-generation space telescopes go up, it will be fascinating to know what these planets are really like.

See the full article here .

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Once called “the first American university” by educational historian Frederick Rudolph, Cornell University represents a distinctive mix of eminent scholarship and democratic ideals. Adding practical subjects to the classics and admitting qualified students regardless of nationality, race, social circumstance, gender, or religion was quite a departure when Cornell was founded in 1865.

Today’s Cornell reflects this heritage of egalitarian excellence. It is home to the nation’s first colleges devoted to hotel administration, industrial and labor relations, and veterinary medicine. Both a private university and the land-grant institution of New York State, Cornell University is the most educationally diverse member of the Ivy League.

On the Ithaca campus alone nearly 20,000 students representing every state and 120 countries choose from among 4,000 courses in 11 undergraduate, graduate, and professional schools. Many undergraduates participate in a wide range of interdisciplinary programs, play meaningful roles in original research, and study in Cornell programs in Washington, New York City, and the world over.

From University of New South Wales: “Self-aligning microscope smashes limits of super-resolution microscopy”

From University of New South Wales

20 Apr 2020

An ultra-precise microscope that surpasses the limitations of Nobel Prize-winning super-resolution microscopy will let scientists directly measure distances between individual molecules.

A T cell with precise localisation of T cell receptors (pink) and CD45 phosphatase (green). Image: Single Molecule Science

UNSW medical researchers have achieved unprecedented resolution capabilities in single-molecule microscopy to detect interactions between individual molecules within intact cells.

The 2014 Nobel Prize in Chemistry was awarded for the development of super-resolution fluorescence microscopy technology that afforded microscopists the first molecular view inside cells, a capability that has provided new molecular perspectives on complex biological systems and processes.

Now the limit of detection of single-molecule microscopes has been smashed again, and the details are published in the current issue of Science Advances.

While individual molecules could be observed and tracked with super-resolution microscopy already, interactions between these molecules occur at a scale at least four times smaller than that resolved by existing single-molecule microscopes.

“The reason why the localisation precision of single-molecule microscopes is around 20-30 nanometres normally is because the microscope actually moves while we’re detecting that signal. This leads to an uncertainty. With the existing super-resolution instruments, we can’t tell whether or not one protein is bound to another protein because the distance between them is shorter than the uncertainty of their positions,” says Scientia Professor Katharina Gaus, research team leader and Head of UNSW Medicine’s EMBL Australia Node in Single Molecule Science.

To circumvent this problem, the team built autonomous feedback loops inside a single-molecule microscope that detects and re-aligns the optical path and stage.

“It doesn’t matter what you do to this microscope, it basically finds its way back with precision under a nanometre. It’s a smart microscope. It does all the things that an operator or a service engineer needs to do, and it does that 12 times per second,” says Professor Gaus.

Measuring the distance between proteins

With the design and methods outlined in the paper, the feedback system designed by the UNSW team is compatible with existing microscopes and affords maximum flexibility for sample preparation.

“It’s a really simple and elegant solution to a major imaging problem. We just built a microscope within a microscope, and all it does is align the main microscope. That the solution we found is simple and practical is a real strength as it would allow easy cloning of the system, and rapid uptake of the new technology,” says Professor Gaus.

To demonstrate the utility of their ultra-precise feedback single-molecule microscope, the researchers used it to perform direct distance measurements between signalling proteins in T cells. A popular hypothesis in cellular immunology is that these immune cells remain in a resting state when the T cell receptor is next to another molecule that acts as a brake.

Their high precision microscope was able to show that these two signalling molecules are in fact further separated from each other in activated T cells, releasing the brake and switching on T cell receptor signalling.

“Conventional microscopy techniques would not be able to accurately measure such a small change as the distance between these signalling molecules in resting T cells and in activated T cells only differed by 4–7 nanometres,” says Professor Gaus.

“This also shows how sensitive these signalling machineries are to spatial segregation. In order to identify regulatory processes like these, we need to perform precise distance measurements, and that is what this microscope enables. These results illustrate the potential of this technology for discoveries that could not be made by any other means.”

Postdoctoral researcher, Dr Simao Pereira Coelho, together with PhD student Jongho Baek – who has since been awarded his PhD degree – led the design, development, and building of this system. Dr Baek also received the Dean’s Award for Outstanding PhD Thesis for this work.

See the full article here .

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Welcome to UNSW Australia (The University of New South Wales), one of Australia’s leading research and teaching universities. At UNSW, we take pride in the broad range and high quality of our teaching programs. Our teaching gains strength and currency from our research activities, strong industry links and our international nature; UNSW has a strong regional and global engagement.

In developing new ideas and promoting lasting knowledge we are creating an academic environment where outstanding students and scholars from around the world can be inspired to excel in their programs of study and research. Partnerships with both local and global communities allow UNSW to share knowledge, debate and research outcomes. UNSW’s public events include concert performances, open days and public forums on issues such as the environment, healthcare and global politics. We encourage you to explore the UNSW website so you can find out more about what we do.

From Science News: “Here’s how the periodic table gets new elements”

From Science News

April 14, 2020
Helen Thompson

From discovery to confirmation and naming, the path is rarely simple.

For would-be elements, the road to the periodic table is long, hard, at times pedantic and quite dramatic. Credit: Dani Nunes

It’s not every day an element gets added to the periodic table. The last time it happened was 2016, when four new elements became official.

For these elements, reaching the table was an epic quest spanning more than a decade. It required rare radioactive ingredients, violent atom smashing, painstaking detection, a mountain of paperwork and a fair amount of waiting before the elements became undisputed champions. But in the end, the newcomers made it into the canon that governs chemistry, filling out the periodic table’s seventh row.

Today, scientists continue pushing the table to its limits, as they hunt for the next elements.

SMASH HIT To create new elements and study the chemistry of the periodic table’s heaviest atoms, researchers at the GSI Helmholtz Center for Heavy Ion Research in Darmstadt, Germany, use the apparatus above to create beams of ions that scientists then smash into other elements. Credit: GSI Helmholtzzentrum für Schwerionenforschung GmbH/Jan Michael Hosan 2018

It’s too soon to say when element 119 or 120 might enter the spotlight. But the International Union of Pure and Applied Chemistry and the International Union of Pure and Applied Physics (IUPAC and IUPAP), which evaluate new element claims, have set out key steps and guidelines for becoming an element. So we know a thing or two about what it will take.

Follow the journey in the video below. It may be a long and arduous process, but when you break it down, getting a spot on the periodic table has all the excitement and drama of a reality TV singing competition.

Follow the journey in the video below. It may be a long and arduous process, but when you break it down, getting a spot on the periodic table has all the excitement and drama of a reality TV singing competition.

See the full article here .

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From SLAC National Accelerator Lab: “In a first, researchers use ultrafast ‘electron camera’ to learn about molecules in liquid samples”

From SLAC National Accelerator Lab

April 9, 2020
Ali Sundermier

This new technology could enable future insights into chemical and biological processes that occur in solution, such as vision, catalysis and photosynthesis.

High-speed “electron cameras” can detect tiny molecular movements in a material by scattering a powerful beam of electrons off a sample. Until recently, researchers had only used this technique to study gases and solids. But some of the most important biological and chemical processes, in particular the conversion of light into energy, happen in molecules in a solution.

Now, researchers have applied this technique, ultrafast electron diffraction, to molecules in liquid samples. They developed a method to create 100-nanometer thick liquid jets–about 1,000 times thinner than the width of a human hair–that enable them to get clear diffraction patterns from electrons. In the future, this method could allow them to explore light-driven processes such as vision, catalysis, photosynthesis and DNA damage caused by UV rays.

The team, which included researchers from the Department of Energy’s SLAC National Accelerator Laboratory, Stanford University and the University of Nebraska-Lincoln (UNL), published their results in Structural Dynamics in March.

“This research is a huge breakthrough in the field of ultrafast electron diffraction,” says Xijie Wang, director of the MeV-UED instrument, who co-authored the paper. “Being able to study biological and chemical systems in their natural environment is a valuable tool that opens up a new window for the future.”

Stop-motion movies

Liquid jets have long been used to deliver samples at X-ray lasers such as SLAC’s Linac Coherent Light Source (LCLS) [below], providing valuable information about ultrafast processes as they occur in their natural environment.

SLAC’s ultrafast “electron camera,” MeV-UED, uses high-energy electron beams to complement the range of structural information collected at LCLS.

SLAC Megaelectronvolt Ultrafast Electron Diffraction Instrument: MeV-UED

Here, scientists begin by exciting a sample with laser light, kicking off the processes they hope to study. Next they blast the sample with a short pulse of electrons with high energy, measured in millions of electronvolts (MeV), to look inside, generating snapshots of its shifting atomic structure that can be strung together into a stop-motion movie of the light-induced structural changes in the sample.

Looking into the kaleidoscope

The tiny wavelengths of these high-energy electrons allow scientists to take high-resolution snapshots, offering insight into processes such as proton transfer and hydrogen-bond breaking that are difficult to study with other methods. But applying this technique to liquid samples has proven challenging.

“Since electrons don’t penetrate samples as easily as X-rays,” says Kathryn Ledbetter, a graduate student at the Stanford PULSE Institute who coauthored the paper, “applying this technique to liquids has been a longstanding challenge in the field.”

If the sample is too thick, the electrons can get stuck and scatter multiple times, producing a wild mix of patterns that’s difficult to glean information from, like looking through a kaleidoscope. In this new study, the team overcame those challenges through the use of MeV electrons and a gas-accelerated thin liquid sheet jet. As the electrons break through the jet, they scatter only once, producing a clean pattern that’s much easier to reconstruct. The team also designed a chamber that housed the liquid jet and monitored the interaction between the sample and the electron beam.

‘Another tool in the ultrafast toolbox’

This paper sets the stage for upcoming research that investigates questions such as what happens when hydrogen bonds break or when molecules absorb UV radiation. As a next step, SLAC researchers are upgrading the MeV-UED facility and developing a new generation of direct electron detectors that will greatly expand the scientific reach of this technique.

“We’d like this to be another tool in the toolbox of researchers trying to learn about liquids and light-driven reactions,” says Pedro Nunes, a postdoctoral researcher at UNL who led the research. “We want to show the community that what was once believed to be far-fetched is not only possible, but capable of running smoothly enough to watch structural changes unfold in real time.”

UED-MeV and LCLS are DOE Office of Science user facilities. The project was funded by the Office of Science.

See the full article here .

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SLAC National Accelerator Lab

SLAC/LCLS

SLAC/LCLS II projected view

SLAC is a multi-program laboratory exploring frontier questions in photon science, astrophysics, particle physics and accelerator research. Located in Menlo Park, California, SLAC is operated by Stanford University for the DOE’s Office of Science.

SSRL and LCLS are DOE Office of Science user facilities.

From University of Michigan: “Stone-age ‘likes’: Study establishes eggshell beads exchanged over 30,000 years”

From University of Michigan

March 9, 2020
Morgan Sherburne
morganls@umich.edu

Archeologists work at rock shelters at Sehonghong and Melikane in southern Africa. Image credit: Brian Stewart.

A clump of grass grows on an outcrop of shale 33,000 years ago. An ostrich pecks at the grass, and atoms taken up from the shale and into the grass become part of the eggshell the ostrich lays.

A member of a hunter-gatherer group living in southern Africa’s Karoo Desert finds the egg. She eats it, and cracks the shell into dozens of pieces. Drilling a hole, she strings the fragments onto a piece of sinew and files them into a string of beads.

She gifts the ornaments to friends who live to the east, where rainfall is higher, to reaffirm those important relationships. They, in turn, do the same, until the beads eventually end up with distant groups living high in the eastern mountains.

Ostrich eggshell beads have been used to cement relationships in Africa for more than 30,000 years. Image credit: John Klausmeyer, Yuchao Zhao and Brian Stewart.

Thirty-three thousand years later, a University of Michigan researcher finds the beads in what is now Lesotho, and by measuring atoms in the beads, provides new evidence for where these beads were made, and just how long hunter-gatherers used them as a kind of social currency.

In a study published in the Proceedings of the National Academy of Science, U-M paleolithic archeologist Brian Stewart and colleagues establish that the practice of exchanging these ornaments over long distances spans a much longer period of time than previously thought.

“Humans are just outlandishly social animals, and that goes back to these deep forces that selected for maximizing information, information that would have been useful for living in a hunter-gatherer society 30,000 years ago and earlier,” said Stewart, assistant professor of anthropology and assistant curator of the U-M Museum of Anthropological Archaeology.

“Ostrich eggshell beads and the jewelry made from them basically acted like Stone Age versions of Facebook or Twitter ‘likes,’ simultaneously affirming connections to exchange partners while alerting others to the status of those relationships.”

Lesotho is a small country of mountain ranges and rivers. It has the highest average of elevation in the continent and would have been a formidable place for hunter-gatherers to live, Stewart says. But the fresh water coursing through the country and belts of resources, stratified by the region’s elevation, provided protection against swings in climate for those who lived there, as early as 85,000 years ago.

Anthropologists have long known that contemporary hunter-gatherers use ostrich eggshell beads to establish relationships with others. In Lesotho, archeologists began finding small ornaments made of ostrich eggshell. But ostriches don’t typically live in that environment, and the archeologists didn’t find evidence of those ornaments being made in that region—no fragments of unworked eggshell, or beads in various stages of production.

So when archeologists began discovering eggshell beads without evidence of production, they suspected the beads arrived in Lesotho through these exchange networks. Testing the beads using strontium isotope analysis would allow the archeologists to pinpoint where they were made.

Strontium-87 is the daughter isotope of the radioactive element rubidium-87. When rubidium-87 decays it produces strontium-87. Older rocks such as granite and gneiss have more strontium than younger rocks such as basalt. When animals forage from a landscape, these strontium isotopes are incorporated into their tissues.

Lesotho is roughly at the center of a bullseye-shaped geologic formation called the Karoo Supergroup. The supergroup’s mountainous center is basalt, from relatively recent volcanic eruptions that formed the highlands of Lesotho. Encircling Lesotho are bands of much older sedimentary rocks. The outermost ring of the formation ranges between 325 and 1,000 kilometers away from the Lesotho sites.

To assess where the ostrich eggshell beads were made, the research team established a baseline of strontium isotope ratios—that is, how much strontium is available in a given location—using vegetation and soil samples as well samples from modern rodent tooth enamel from museum specimens collected from across Lesotho and surrounding areas.

According to their analysis, nearly 80% of the beads the researchers found in Lesotho could not have originated from ostriches living near where the beads were found in highland Lesotho.

“These ornaments were consistently coming from very long distances,” Stewart said. “The oldest bead in our sample had the third highest strontium isotope value, so it is also one of the most exotic.”

Stewart found that some beads could not have come from closer than 325 kilometers from Lesotho, and may have been made as far as 1,000 kilometers away. His findings also establish that these beads were exchanged during a time of climactic upheaval, about 59 to 25 thousand years ago. Using these beads to establish relationships between hunter-gatherer groups ensured one group access to others’ resources when a region’s weather took a turn for the worse.

“What happened 50,000 years ago was that the climate was going through enormous swings, so it might be no coincidence that that’s exactly when you get this technology coming in,” Stewart said. “These exchange networks could be used for information on resources, the condition of landscapes, of animals, plant foods, other people and perhaps marriage partners.”

Stewart says while archeologists have long accepted that these exchange items bond people over landscapes in the ethnographic Kalahari, they now have firm evidence that these beads were exchanged over huge distances not only in the past, but for over a long period of time. This study places another piece in the puzzle of how we persisted longer than all other humans, and why we became the globe’s dominant species.

Stewart’s co-authors include U-M graduate student Yuchao Zhao, as well as Peter Mitchell the University of Oxford, Genevieve Dewar of the University of Toronto Scarborough, and U-M’s James Gleason and Joel Blum.

See the full article here .

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Please support STEM education in your local school system

Stem Education Coalition

The University of Michigan (U-M, UM, UMich, or U of M), frequently referred to simply as Michigan, is a public research university located in Ann Arbor, Michigan, United States. Originally, founded in 1817 in Detroit as the Catholepistemiad, or University of Michigania, 20 years before the Michigan Territory officially became a state, the University of Michigan is the state’s oldest university. The university moved to Ann Arbor in 1837 onto 40 acres (16 ha) of what is now known as Central Campus. Since its establishment in Ann Arbor, the university campus has expanded to include more than 584 major buildings with a combined area of more than 34 million gross square feet (781 acres or 3.16 km²), and has two satellite campuses located in Flint and Dearborn. The University was one of the founding members of the Association of American Universities.

Considered one of the foremost research universities in the United States,[7] the university has very high research activity and its comprehensive graduate program offers doctoral degrees in the humanities, social sciences, and STEM fields (Science, Technology, Engineering and Mathematics) as well as professional degrees in business, medicine, law, pharmacy, nursing, social work and dentistry. Michigan’s body of living alumni (as of 2012) comprises more than 500,000. Besides academic life, Michigan’s athletic teams compete in Division I of the NCAA and are collectively known as the Wolverines. They are members of the Big Ten Conference.

From UC Riverside: “A possible end to ‘forever’ chemicals”

From UC Riverside

March 10, 2020
Holly Ober

Excess electrons could help break the strong chemical bonds in products that contaminate water supplies.

Synthetic chemicals known as per- and polyfluoroalkyls, or PFAS, contain bonds between carbon and fluorine atoms considered the strongest in organic chemistry. Unfortunately, the widespread use of these nonbiodegradable products since the 1940s has contaminated many water supplies across America.

Engineers at UC Riverside have now shown in modeling experiments that using excess electrons shatters the carbon-fluorine bond of PFAS in water, leaving by-products that might even accelerate the process. The paper is published in Physical Chemistry Chemical Physics.

Impervious to heat, chemicals, and physical force, the carbon-fluorine bond makes PFAS ubiquitous in food packaging, stain and water repellent fabrics, polishes and waxes, firefighting foams, cleaning products, carpets and thousands of other common household and industrial products. The Environmental Protection Agency estimates that most of the population has been exposed to PFAS that accumulate in the body over time because these “forever chemicals” do not biodegrade.

Sharma Yamijala, a postdoctoral researcher in the Marlan and Rosemary Bourns College of Engineering and first author of the paper, ran simulations on both perfluorooctanoic acid and perfluorooctanesulfonic acid molecules, the most common PFA contaminants in the environment, surrounded by water molecules. He found that they instantly lost their fluorine atom in the presence of excess electrons.

The PFA molecules broke down into an intermediate chemical species whose composition could further accelerate the decomposition of other PFA molecules. The reaction also formed a hydrogen fluoride molecule. Whether or not these shortchain molecules are carcinogens at typical concentrations in water has not yet been determined.

“In a real water treatment scenario, the excess electrons could come from metal-containing compounds placed in the water under ultraviolet radiation. The electrons from these compounds will interact with the PFA molecules and break them,” Yamijala said.

The simulations describe in precise detail a process that scientists have known is possible.

“People knew you could do this but didn’t know why,” said Bryan Wong, an associate professor of chemical and environmental engineering and the paper’s senior author. “Our simulations define the bigger picture that we can refine to find ways to break down PFAs faster or more efficiently in the future.”

The research was supported by grants from the U.S. Department of Energy and the National Science Foundation.

See the full article here .

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Please help promote STEM in your local schools.

Stem Education Coalition

The University of California, Riverside is one of 10 universities within the prestigious University of California system, and the only UC located in Inland Southern California.

Widely recognized as one of the most ethnically diverse research universities in the nation, UCR’s current enrollment is more than 21,000 students, with a goal of 25,000 students by 2020. The campus is in the midst of a tremendous growth spurt with new and remodeled facilities coming on-line on a regular basis.

We are located approximately 50 miles east of downtown Los Angeles. UCR is also within easy driving distance of dozens of major cultural and recreational sites, as well as desert, mountain and coastal destinations.

From UCLA Newsroom: “UCLA-led research team produces most accurate 3D images of ‘2D materials’”

From UCLA Newsroom

March 9, 2020
Wayne Lewis

Image showing the 3D atomic coordinates of molybdenum (blue), sulfur (yellow) and added rhenium (orange). A 2D image is shown beneath the 3D model.

Scientists develop innovative technique to pinpoint coordinates of single atoms.

A UCLA-led research team has produced in unprecedented detail experimental three-dimensional maps of the atoms in a so-called 2D material — matter that isn’t truly two-dimensional but is nearly flat because it’s arranged in extremely thin layers, no more than a few atoms thick.

Although 2D-materials–based technologies have not yet been widely used in commercial applications, the materials have been the subject of considerable research interest. In the future, they could be the basis for semiconductors in ever smaller electronics, quantum computer components, more-efficient batteries, or filters capable of extracting freshwater from saltwater.

The promise of 2D materials comes from certain properties that differ from how the same elements or compounds behave when they appear in greater quantities. Those unique characteristics are influenced by quantum effects — phenomena occurring at extremely small scales that are fundamentally different from the classical physics seen at larger scales. For instance, when carbon is arranged in an atomically thin layer to form 2D graphene, it is stronger than steel, conducts heat better than any other known material, and has almost zero electrical resistance.

But using 2D materials in real-world applications would require a greater understanding of their properties, and the ability to control those properties. The new study, which was published in Nature Materials, could be a step forward in that effort.

The researchers showed that their 3D maps of the material’s atomic structure are precise to the picometer scale — measured in one-trillionths of a meter. They used their measurements to quantify defects in the 2D material, which can affect their electronic properties, as well as to accurately assess those electronic properties.

“What’s unique about this research is that we determine the coordinates of individual atoms in three dimensions without using any pre-existing models,” said corresponding author Jianwei “John” Miao, a UCLA professor of physics and astronomy. “And our method can be used for all kinds of 2D materials.”

Miao is the deputy director of the STROBE National Science Foundation Science and Technology Center and a member of the California NanoSystems Institute at UCLA. His UCLA lab collaborated on the study with researchers from Harvard University, Oak Ridge National Laboratory and Rice University.

The researchers examined a single layer of molybdenum disulfide, a frequently studied 2D material. In bulk, this compound is used as a lubricant. As a 2D material, it has electronic properties that suggest it could be employed in next-generation semiconductor electronics. The samples being studied were “doped” with traces of rhenium, a metal that adds spare electrons when replacing molybdenum. That kind of doping is often used to produce components for computers and electronics because it helps facilitate the flow of electrons in semiconductor devices.

To analyze the 2D material, the researchers used a new technology they developed based on scanning transmission electron microscopy, which produces images by measuring scattered electrons beamed through thin samples. Miao’s team devised a technique called scanning atomic electron tomography, which produces 3D images by capturing a sample at multiple angles as it rotates.

The scientists had to avoid one major challenge to produce the images: 2D materials can be damaged by too much exposure to electrons. So for each sample, the researchers reconstructed images section by section and then stitched them together to form a single 3D image — allowing them to use fewer scans and thus a lower dose of electrons than if they had imaged the entire sample at once.

The two samples each measured 6 nanometers by 6 nanometers, and each of the smaller sections measured about 1 nanometer by 1 nanometer. (A nanometer is one-billionth of a meter.)

The resulting images enabled the researchers to inspect the samples’ 3D structure to a precision of 4 picometers in the case of molybdenum atoms — 26 times smaller than the diameter of a hydrogen atom. That level of precision enabled them to measure ripples, strain distorting the shape of the material, and variations in the size of chemical bonds, all changes caused by the added rhenium — marking the most accurate measurement ever of those characteristics in a 2D material.

“If we just assume that introducing the dopant is a simple substitution, we wouldn’t expect large strains,” said Xuezeng Tian, the paper’s co-first author and a UCLA postdoctoral scholar. “But what we have observed is more complicated than previous experiments have shown.”

The scientists found that the largest changes occurred in the smallest dimension of the 2D material, its three-atom-tall height. It took as little as a single rhenium atom to introduce such local distortion.

Armed with information about the material’s 3D coordinates, scientists at Harvard led by Professor Prineha Narang performed quantum mechanical calculations of the material’s electronic properties.

“These atomic-scale experiments have given us a new lens into how 2D materials behave and how they should be treated in calculations, and they could be a game changer for new quantum technologies,” Narang said.

Without access to the sort of measurements generated in the study, such quantum mechanical calculations conventionally have been based on a theoretical model system that is expected at a temperature of absolute zero.

The study indicated that the measured 3D coordinates led to more accurate calculations of the 2D material’s electronic properties.

“Our work could transform quantum mechanical calculations by using experimental 3D atomic coordinates as direct input,” said UCLA postdoctoral scholar Dennis Kim, a co-first author of the study. “This approach should enable material engineers to better predict and discover new physical, chemical and electronic properties of 2D materials at the single-atom level.”

Other authors were Yongsoo Yang, Yao Yang and Yakun Yuan of UCLA; Shize Yang and Juan-Carlos Idrobo of Oak Ridge National Laboratory; Christopher Ciccarino and Blake Duschatko of Harvard; and Yongji Gong and Pulickel Ajayan of Rice.

The research was supported by the U.S. Department of Energy, the U.S. Army Research Office, and STROBE National Science Foundation Science and Technology Center. The scanning transmission electron microscopy experiments were conducted at the Center for Nanophase Materials Sciences, a DOE user facility at Oak Ridge National Laboratory.

See the full article here .

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Please help promote STEM in your local schools.

Stem Education Coalition

For nearly 100 years, UCLA has been a pioneer, persevering through impossibility, turning the futile into the attainable.

We doubt the critics, reject the status quo and see opportunity in dissatisfaction. Our campus, faculty and students are driven by optimism. It is not naïve; it is essential. And it has fueled every accomplishment, allowing us to redefine what’s possible, time after time.

This can-do perspective has brought us 12 Nobel Prizes, 12 Rhodes Scholarships, more NCAA titles than any university and more Olympic medals than most nations. Our faculty and alumni helped create the Internet and pioneered reverse osmosis. And more than 100 companies have been created based on technology developed at UCLA.