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Esther Takeuchi

Esther S. Takeuchi, PhD, Distinguished Professor and the William and Jane Knapp Chair at Stony Brook University is being honored by the National Academy of Sciences (NAS) and will receive the Award in Chemical Sciences. This award is in recognition of her breakthrough contributions in the understanding of electrochemical energy storage.  

Takeuchi, who holds a joint appointment at Department of Energy’s (DOE) Brookhaven National Laboratory, is an internationally recognized inventor, researcher, and educator in the fields of materials science, chemistry and renewable energy. She will be honored in a ceremony during the NAS 159th annual meeting on May 1 and will receive a medal and prize of $15,000 sponsored by the Merck Company Foundation.

The award cites Takeuchi’s contributions “to the materials and mechanistic understanding relevant to electrochemical energy storage, using chemical insight to address issues of critical importance.”

“I am sincerely honored to receive the National Academy of Science Award for Chemical Sciences,” said Takeuchi, also the Knapp Chair Professor of Energy and the Environment in the Department of Materials Science and Chemical Engineering “The fundamental chemistry of electrochemical energy storage is complex and the subsequent development of viable energy storage devices is made even more challenging by the unique demands of each application.”

Takeuchi’s research has been instrumental in energy storage improvements that meet societal needs and can be applied to electric vehicles, medical devices, and batteries that back up the power grid. Among her numerous and notable inventions is a compact lithium/silver vanadium oxide battery that increased the lifespan of implantable cardiac defibrillators, a solution that reduced the number of surgeries patients needed to undergo to replace the devices that detect and correct irregular, potentially fatal, heart rhythms.

Takeuchi was recently elected a member of the American Academy of Arts and Sciences. She has also been inducted into the National Academy of Engineering and selected as a Fellow of the American Institute for Medical and Biological Engineering and the American Association for the Advancement of Science. She was selected as the 2013 recipient of the E.V. Murphree Award in Industrial and Engineering Chemistry from the American Chemical Society. She was inducted into the National Inventors Hall of Fame in 2011. In 2009, President Obama presented Takeuchi with the National Medal of Technology and Innovation, the highest honor possible for technological achievement in the United States.

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Ostrich eggshell beads found at the Mlambalasi site. These beads are examples of Later Stone Age cultural objects that people created and traded as they traveled the continent. Photo by Jennifer Miller

Ancient DNA from the remains of nearly three dozen African foragers—groups associated with hunting, gathering, and fishing—sheds new light on how groups across sub-Saharan Africa lived, traveled and settled prior to the spread of herding and farming. The study involved an international team of 44 researchers including experts from Stony Brook University. The findings, to be published in Nature, produced the earliest DNA of humans on the continent, at some 5,000 to 18,000 years old.

View of the Mlambalasi Rock Shelter in Tanzania, where one of the newly DNA sequenced individuals was recovered by Elizabeth Sawchuk in 2010. Radiocarbon dates suggest that this individual lived approximately 18,000 years ago, making their DNA the oldest currently known in Africa. Photo by Katie Biittner

The new genetic findings add weight to archeological, skeletal and linguistic evidence for changes in how people were moving and interacting across Africa toward the end of the Ice Ages. Around 50,000 years ago, distinct groups of foragers began exhibiting similar cultural traditions, hinting at the development of exchange networks and interregional connections. The reason for this shift, which archaeologists refer to as the Later Stone Age transition, has remained a mystery.

“We demonstrated for the first time that a major archeological transition some 50,000 years ago associated with profound shifts in technology, symbolism, and so-called ‘modern behavior’ in fact coincided with major demographic changes,” said Elizabeth Sawchuk, PhD, Co-First Author, Research Assistant Professor at Stony Brook University and a Banting Postdoctoral Fellow at the University of Alberta. “We found that ancient foragers across eastern and south-central Africa are a mix of eastern, southern, and central African ancestry, showing there was widespread movement and mixing across sub-Saharan Africa coinciding with the transition from the Middle to Later Stone Age.”

Previous research proposed a genetic cline (or gradient) of variation among ancient African foragers extending from eastern to southern Africa. To the research team’s surprise, this new analysis indicates a three-way cline instead of a two-way cline that includes a central African ancestry – a significant point of future investigation because there has been less archeological research in central Africa than other parts of the continent.

“By associating archaeological artifacts with ancient DNA, the researchers have created a remarkable framework for exploring the prehistory of humans in Africa,” says Archaeology and Archaeometry program director John Yellen of the U.S. National Science Foundation, one of the funders behind this project. “This insight is charting a new way forward to understanding humanity and our complex shared history.”

Sawchuk and Stony Brook colleague and Co-Author Jason Lewis, PhD, presented ancient DNA (aDNA) from six individuals from the Late Pleistocene and early Holocene from five sites in Tanzania, Zambia, and Malawi

These six individuals have now yielded the oldest human DNA from sub-Saharan Africa.

The six individuals were analyzed with 28 previously published ancient persons associated with foraging and/or Later Stone Age material culture. The research team also generated higher coverage data for fifteen of these individuals which permitted a more in-depth look at their DNA.

Lewis co-led a team reanalyzing the history of work and collections from the ancient Tanzanian rockshelter site of Kisese II, particularly in the context and dating of the human remains, allowing the collection to be included in the present study. The skeletons from the site were originally excavated in the 1960s but remained unstudied until recently.

“The work is a great example of the unexpected and important results that can come from going back to old museum collections to take another look with new approaches and technologies, in this case using aDNA methods,” said Lewis.

Ancient DNA and archaeological data now both point toward a demographic transition across Africa around the time that beads, pigments, and symbolic art became more widespread. Sawchuk, Lewis and colleagues note that while scientists have proposed shifts in social networks and perhaps changes in populations sizes played a role, such hypotheses have remained difficult to test.

“We’ve never been able to directly explore proposed demographic shifts until now,” explains Sawchuk. “It has been difficult to reconstruct events in our deeper past using the DNA of people living today, and artifacts can’t tell the whole story. The DNA from people who lived around this time provides the missing piece of the puzzle, offering an unprecedented view of population structures among ancient foragers.”

While this three-way population structure can only be explained by widespread movement and mixing in the past, the researchers also note that the traveling and mixing didn’t last.

Individuals in this study were most genetically similar to their geographic neighbors, which suggests that by 20,000 years ago, people had already stopped moving as much. The authors explain this coincides with archaeological evidence for “regionalization” toward the end of the Ice Ages when Later Stone Age industries began to diversity and take on distinctive local attributes. So while stone and beads continued moving through exchange networks, people themselves began living more locally.

Mary Prendergast, the study’s co-Senior Author and Associate Professor of Anthropology at Rice University, said there are arguments that the development and expansion of long-distance trade networks around these ancient times helped humans weather the last Ice Age.

“Humans began relying on each other in new ways,” she said. “And this shift in how people interacted with one another may have been what allowed people to thrive.

“The work also helps address the global imbalance of research, as there are around 30 times more published ancient DNA sequences from Europe than from Africa,” she added. “Given that Africa harbors the greatest human genetic diversity on the plant, we have much more to learn.”

The entire research team included scholars from the United States, Canada, Kenya, Malawi, Tanzania, Zambia and several other countries. Critical contributions to the study came from curators and co-authors from African museums who are responsible for protecting and preserving the remains.

 

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Christopher Vakoc. Photo from CSHL

By Daniel Dunaief

Diseases like cancer take the normal raw materials of a cell and make them a part of a pernicious process that often threatens a person’s health.

Ideally, when researchers find the raw materials cancers need to survive, they discover specific proteins that are necessary for cancer, but aren’t critical for healthy cells.

That appears to have happened recently in the lab of Cold Spring Harbor Laboratory Professor Chris Vakoc in the study of the blood disease Acute Myeloid Leukemia, or AML.

Vakoc’s former graduate student Sofya Polyanskaya, who now works in a pharmaceutical company in Germany, discovered the importance of an understudied protein called SCP4, which removes phosphate groups from other proteins, in some forms of AML. This protein acts as an enzyme, which makes it a particularly appealing target.

In his lab, Vakoc said he and his researchers take “genes and the proteins they encode and [try to] publish the first paper linking them to cancer,” Vakoc said.

Polyanskaya and Vakoc recently published their findings in the journal Cell Reports.

These scientists disabled proteins in a host of diverse cancer types, looking for dependencies that were unique to each cancer. After determining that SCP4 was only needed in leukemia and not other cancers, they inactivated the protein in normal, healthy blood cells and found that it wasn’t needed.

“Leukemia cells are super sensitive to the loss of this enzyme,” Vakoc said.

Vakoc praised the work of Polyanskaya, who he said conducted the “inspiring work” that led to this conclusion. “It’s not easy for a brand new scientist entering the field to write the first cancer paper on a target.”

Polyanskaya surveyed hundreds of these enzymes to find a potential new protein that cancer, specifically, might need. The CRISPR technology, which didn’t exist nine years ago, provides a way of altering a large number of potential enzymes to find the ones that are critical for cancer’s survival.

Ideally, this kind of analysis enables researchers like Polyanskaya and Vakoc to focus in on the ones that are critical to cancer, but that don’t perform any important function in normal cells.

One of the other benefits of this work is that it validates the importance of targets that have become the focus of other research projects.

“Part of what we’re doing is making sure that our processes more broadly in the field are robust,” Vakoc said. “We are more confident in other targets we didn’t discover” but that play a role in the progression of leukemia.

To be sure, the discovery of the SCP4 target is the first step in a series of questions that may require considerable time and resources to ensure a reliable and safe clinical benefit.

As with many cancers, leukemia may have the equivalent of a back up plan, in case this seemingly important enzyme is unavailable. Indeed, the battle against cancer and other diseases involves moves and counter moves by pharmaceutical and biotechnology companies and the diseases they battle.

Additionally, researchers like Vakoc need to discover the reason cells produce this enzyme in the first place. Mice lacking SCP4 are born, but develop metabolic stress after birth.

“The important experiment in the future will be to determine what the consequences of targeting SCP4 are in normal tissue much later after birth,” Vakoc explained in an email.

Like other cancers, leukemia is a heterogeneous disease, which is another way of saying that not everyone with the disease has the same symptoms and prognosis and not everyone would respond to the same treatment in the same way.

Vakoc would like to figure out for “which subset of patients with leukemia is this protein the most important. Down the road, that could help determine who might benefit from an SCP4 inhibitor.

“We want to personalize therapy as much as possible,” he said.

In his follow up research, Vakoc hopes to learn more about the three-dimensional structure of the protein complex.

Vakoc’s interest in leukemia stems from his interest in studying blood. When he conducted his PhD training at the University of Pennsylvania, he studied normal blood development.

He was particularly interested in pediatric cancer. While AML is on of the cancers that children can develop, it is far more common in elderly people.

The lab has a strong focus on leukemia.

Vakoc, whose lab is next door to CSHL Cancer Center Director David Tuveson, has also starting searching for potential therapeutic targets in pancreatic cancer.

He is excited about the potential to bring attention to a possible candidate that may provide a therapeutic benefit for patients at some point.

“It feels good to put a new target on the map,” he said.

The CSHL scientist recognizes that cancer can and often does develop resistance to a treatment that tackles any one enzyme or protein. Still, he said treating cancer with any new and effective therapy could extend life by several months, which are often “very valuable to patients.”

Vakoc suggested that any potential new treatment for leukemia would likely involve several drugs working together to stay ahead of cancer.

“The real hope and optimism is that, if you had a copule of targets like this that are not needed in healthy cells, you could add 10 or 20 years of high quality life. You could keep the disease in a chronic, latent state.”

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Members of the research team include: Daniel Mazzone (formerly of Brookhaven Lab, now at the Paul Scherrer Institut in Switzerland), Yao Shen (Brookhaven Lab), Gilberto Fabbris (Argonne National Laboratory), Hidemaro Suwa (University of Tokyo and University of Tennessee), Hu Miao (Oak Ridge National Laboratory—ORNL), Jennifer Sears* (Brookhaven Lab), Jian Liu (U Tennessee), Christian Batista (U Tennessee and ORNL), and Mark Dean (Brookhaven Lab). *Photo Credit: DESY, Marta Mayer
Scientists identify a long-sought magnetic state predicted  60 years ago
Scientists at the U.S. Department of Energy’s Brookhaven National Laboratory have discovered a long-predicted magnetic state of matter called an “antiferromagnetic excitonic insulator.”
“Broadly speaking, this is a novel type of magnet,” said Brookhaven Lab physicist Mark Dean, senior author on a paper describing the research just published in Nature Communications. “Since magnetic materials lie at the heart of much of the technology around us, new types of magnets are both fundamentally fascinating and promising for future applications.”
The new magnetic state involves strong magnetic attraction between electrons in a layered material that make the electrons want to arrange their magnetic moments, or “spins,” into a regular up-down “antiferromagnetic” pattern. The idea that such antiferromagnetism could be driven by quirky electron coupling in an insulating material was first predicted in the 1960s as physicists explored the differing properties of metals, semiconductors, and insulators.
“Sixty years ago, physicists were just starting to consider how the rules of quantum mechanics apply to the electronic properties of materials,” said Daniel Mazzone, a former Brookhaven Lab physicist who led the study and is now at the Paul Scherrer Institut in Switzerland. “They were trying to work out what happens as you make the electronic ‘energy gap’ between an insulator and a conductor smaller and smaller. Do you just change a simple insulator into a simple metal where the electrons can move freely, or does something more interesting happen?”
The prediction was that, under certain conditions, you could get something more interesting: namely, the “antiferromagnetic excitonic insulator” just discovered by the Brookhaven team.
Why is this material so exotic and interesting? To understand, let’s dive into those terms and explore how this new state of matter forms.
In an antiferromagnet, the electrons on adjacent atoms have their axes of magnetic polarization (spins) aligned in alternating directions: up, down, up, down and so on. On the scale of the entire material those alternating internal magnetic orientations cancel one another out, resulting in no net magnetism of the overall material. Such materials can be switched quickly between different states. They’re also resistant to information being lost due to interference from external magnetic fields. These properties make antiferromagnetic materials attractive for modern communication technologies.
Next we have excitonic. Excitons arise when certain conditions allow electrons to move around and interact strongly with one another to form bound states. Electrons can also form bound states with “holes,” the vacancies left behind when electrons jump to a different position or energy level in a material. In the case of electron-electron interactions, the binding is driven by magnetic attractions that are strong enough to overcome the repulsive force between the two like-charged particles. In the case of electron-hole interactions, the attraction must be strong enough to overcome the material’s “energy gap,” a characteristic of an insulator.
“An insulator is the opposite of a metal; it’s a material that doesn’t conduct electricity,” said Dean. Electrons in the material generally stay in a low, or “ground,” energy state. “The electrons are all jammed in place, like people in a filled amphitheater; they can’t move around,” he said. To get the electrons to move, you have to give them a boost in energy that’s big enough to overcome a characteristic gap between the ground state and a higher energy level.
An artist’s impression of how the team identified this historic phase of matter. The researchers used x-rays to measure how spins (blue arrows) move when they are disturbed and were able to show that they oscillate in length in the pattern illustrated above. This special behavior occurs because the amount of electrical charge at each site (shown as yellow disks) can also vary and is the fingerprint used to pin down the novel behavior.

In very special circumstances, the energy gain from magnetic electron-hole interactions can outweigh the energy cost of electrons jumping across the energy gap.

Now, thanks to advanced techniques, physicists can explore those special circumstances to learn how the antiferromagnetic excitonic insulator state emerges.
A collaborative team worked with a material called strontium iridium oxide (Sr3Ir2O7), which is only barely insulating at high temperature. Daniel Mazzone, Yao Shen (Brookhaven Lab), Gilberto Fabbris (Argonne National Laboratory), and Jennifer Sears (Brookhaven Lab) used x-rays at the Advanced Photon Source—a DOE Office of Science user facility at Argonne National Laboratory—to measure the magnetic interactions and associated energy cost of moving electrons. Jian Liu and Junyi Yang from the University of Tennessee and Argonne scientists Mary Upton and Diego Casa also made important contributions.
The team started their investigation at high temperature and gradually cooled the material. With cooling, the energy gap gradually narrowed. At 285 Kelvin (about 53 degrees Fahrenheit), electrons started jumping between the magnetic layers of the material but immediately formed bound pairs with the holes they’d left behind, simultaneously triggering the antiferromagnetic alignment of adjacent electron spins. Hidemaro Suwa and Christian Batista of the University of Tennessee performed calculations to develop a model using the concept of the predicted antiferromagnetic excitonic insulator, and showed that this model comprehensively explains the experimental results.
“Using x-rays we observed that the binding triggered by the attraction between electrons and holes actually gives back more energy than when the electron jumped over the band gap,” explained Yao Shen. “Because energy is saved by this process, all the electrons want to do this. Then, after all electrons have accomplished the transition, the material looks different from the high-temperature state in terms of the overall arrangement of electrons and spins. The new configuration involves the electron spins being ordered in an antiferromagnetic pattern while the bound pairs create a ‘locked-in’ insulating state.”
The identification of the antiferromagnetic excitonic insulator completes a long journey exploring the fascinating ways electrons choose to arrange themselves in materials. In the future, understanding the connections between spin and charge in such materials could have potential for realizing new technologies.
Brookhaven Lab’s role in this research was funded by the DOE Office of Science, with collaborators receiving funding from a range of additional sources noted in the paper. The scientists also used computational resources of the Oak Ridge Leadership Computing Facility, a DOE Office of Science user facility at Oak Ridge National Laboratory.
Brookhaven National Laboratory is supported by the Office of Science of the U.S. Department of Energy. The Office of Science is the single largest supporter of basic research in the physical sciences in the United States and is working to address some of the most pressing challenges of our time. For more information, visit science.energy.gov. [https://www.energy.gov/science/]
Related Links
Online version of this news release with related graphics [https://www.bnl.gov/newsroom/news.php?a=119438]
Scientific paper: “Antiferromagnetic Excitonic Insulator State in Sr3Ir2O7” [https://www.nature.com/articles/s41467-022-28207-w]
Media Contacts
Karen McNulty Walsh [mailto:[email protected]], (631) 344-8350, or Peter Genzer [mailto:[email protected]], (631) 344-3174

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Abhay Deshpande with a group of students at Stony Brook University. Photo from SBU

By Daniel Dunaief

The American Association for the Advancement of Science recently named physicist Abhay Deshpande a Fellow.

Abhay Deshpande. Photo from SBU

Deshpande, who thinks big about small matter, has distinguished himself with his discoveries, ideas, leadership, innovation, and mentorship. The Director of Electron Ion Collider Science at Brookhaven National Laboratory (BNL) and SUNY Distinguished Professor at Stony Brook University will become a fellow as part of an online ceremony on Feb. 19.

“I was really pleasantly honored” to be a part of a group that includes so many leaders in science, including actor and science advocate Alan Alda, who founded the eponymous Alan Alda Center for Communicating Science at Stony Brook, said Deshpande.

Deshpande’s collaborators and scientific colleagues said Deshpande deserved the AAAS honor, which the society has given since 1874.

“Everything [Deshpande] has been doing is advancing science,” said Haiyan Gao, Associate Laboratory Director in Nuclear and Particle Physics at BNL.

Fundamental questions

A physicist who earned his bachelor’s degree from the University of Bombay, which is now called the University of Mumbai, his Master’s degree from the Indian Institute of Technology, Kanpur and his PhD at Yale University, Deshpande has put his academic and intellectual talents to work answering fundamental questions about atoms.

In his research, Deshpande studies protons in the nucleus.

Inside protons and neutrons are quarks and gluons, which are fundamental particles. Gluons have no mass and bind the quarks together, which suggests that the mass of protons must come from quarks — except that it doesn’t.

“The surprise is that all quarks together only account for about one percent of the proton’s mass,” Deshpande explained in an email.

Researchers don’t know how the components of quarks and gluons and their energies contribute to the proton’s mass. At the same time, Deshpande wants to know about the origin of a proton’s spin. 

Quarks constitute about a quarter of a proton’s spin and gluon’s another quarter, which suggests that the remaining spin should come from their orbital angular momentum.

Deshpande never thought about the mass deficit until a few years ago because of his focus on a proton’s spin. “The same rotational motion of the quarks and gluons could not only explain the spin, but hopefully explain the mass,” Deshpande said. Such a solution to both unanswered questions would be “elegant,” he said.

EIC champion

A $2 billion Electron Ion Collider, which the Department of Energy awarded BNL in 2020, will take measurements that will study the origin of the remaining spin and mass. BNL will start building the EIC, which will take eight years to construct, in 2024.

Dmitri Kharzeev, Distinguished Professor and Director in the Center for Nuclear Theory at Stony Brook University, helped nominate Deshpande to become a AAAS fellow in part because of his work developing BNL’s EIC bid.

Deshpande “really played a major role in bringing this project to Long Island,” Kharzeev said. “It means a lot for BNL, and it also means a lot for Long Island as a whole. A lot of people will be hired to work on it.”

Kharzeev said Deshpande is the leader of the science effort at the EIC “precisely because of his status in the scientific community.”

Kharzeev said some of Deshpande’s papers are “among the highest-cited papers in experimental nuclear physics,” which is considered a reflection of the importance of the work.

Gao credited Deshpande and other key leaders in the community for preparing a “white paper which laid out the science in a very convincing and powerful way,” which helped make the EIC a reality.

In addition to Deshpande’s accomplishments as a scientist, Kharzeev lauded his colleague’s leadership. Deshpande brought together researchers from BNL and Thomas Jefferson National Accelerator Facility in Virginia, which were originally competing for the rights to build the EIC. He helps researchers “put science first and scientific politics second,” which is a “spectacular achievement,” Kharzeev said.

Throughout his career, Deshpande has sought to find complementary strengths among his colleagues.

He is the founding director of the Center for Frontiers in Nuclear Science, which is a joint operation between BNL and SBU and is passionate about sharing the excitement of research with people who work outside science.

“The science we do, the excitement we feel, needs to be talked about to high school students, to college students, to their parents” and to others, Deshpande added. 

Decision-makers in the government need to understand the benefit of the research, as well as the general public, whose taxes ultimately fund future discoveries, he said, and believes communicating science requires connecting with a range of audiences.

Science communicator

Deshpande’s colleagues gave him high marks for encouraging productive collaborations. He is “able to make very good, easy connections with people,” Gao said and is “approachable and easy to work with.”

Ciprian Gal, Assistant Research Professor at Mississippi State and Visiting Scholar at the Center for Frontiers in Nuclear Science, was a graduate student in Deshpande’s lab from 2010 to 2014

While he appreciated Deshpande’s intellectual acumen and knowledge of physics, Gal admired his mentor’s accessibility and eagerness to share his passion for science.

“He’s always very open” to everyone, Gal said, including students of any age. During Summer Sunday events at BNL, Deshpande spoke at length with middle school students and their parents.

“He instills a desire to communicate in all of us,” said Gal, who also appreciated how Deshpande made himself available to the graduate students in his lab during off hours and on weekends.

Engaging audiences

While he was interested in science during his formative years in high school in Mumbai, India, Deshpande also participated in several dramatic productions that were in Marathi, his native language. Typically, the plays tried to convey messages such as the importance of literacy and education or against blind faith and misinformation. Deshpande sees a benefit to using the techniques of drama to engage the audience.

He believes the EIC will provide precise knowledge of properties of the proton and the nuclei. “I promise that we will learn lots of new things,” he said.

Kindergarten connection

The celebrated physicist is married to Arati Deshpande, who works at American Health Pharmaceuticals. The couple, who met when they were in kindergarten and now live in Miller Place, have a daughter, Pooja, who is a graduate student at the Gillings School of Public Health in Chapel Hill, N.C. and a son, Ameesh, who is in high school.

As for his advice to students, Deshpande urges them to “identify a good scientific problem and pursue it no matter the cost or time.”

 

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A collection of tools found in Grotte Mandrin of both Neanderthals and modern humans. The pointier tools were made by modern humans about 54,000 years ago. Image from Ludovic Slimak
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A collection of tools found in Grotte Mandrin of both Neanderthals and modern humans. The pointier tools were made by modern humans about 54,000 years ago. Image from Ludovic Slimak
Nanopoint (about 10mm long) of the Neronian, technology of the first Modern humans in Europe. 1 :1 scale and enlargement. Visual scale : 1 eurocent. Photo Ludovic Slimak.
Micropoint (below 30mm long) of the Neronian, technology of the first Modern humans in Europe. Photo Ludovic Slimak
View of Grotte Mandrin overhanging the Rhône corridor. The Rhône is the second river of the Mediterranean sea after the Nile and the most important natural corridor linking mediterranean and continental Europe. Photo Ludovic Slimak.
View of Grotte Mandrin. Photo Ludovic Slimak
View of Grotte Mandrin overhanging the Rhône corridor. The Rhône is the second river of the Mediterranean sea after the Nile and the most important natural corridor linking mediterranean and continental Europe. Photo Ludovic Slimak.
View of the Rhône river at the latitude of Grotte Mandrin. The Rhône is the second river of the Mediterranean sea after the Nile and the most important natural corridor linking mediterranean and continental Europe. Photo Ludovic Slimak.
Vertical view of the Grotte Mandrin. Photo Rob Hope.
View of the excavations at the entrace of Grotte Mandrin cave. Photo Ludovic Slimak.
View of the excavations at the entrace of Grotte Mandrin cave. Photo Ludovic Slimak.
View of an in situ long blade of the Neronian of Grotte Mandrin, technology of the first Modern humans in Europe. Photo Ludovic Slimak
Marine Frouin drilling at the Grotte Mandrin to collect samples. Photo by Ludovic Slimak
This diagram shows how long ago the Neanderthal teeth were found in the cave and the crucial level at which a homo sapien tooth was found in the cave. (Ka stands for thousands). Image from Ludovic Slimak
View of the excavations at the entrace of Grotte Mandrin cave. Photo Ludovic Slimak.
Dr Ludovic Slimak, director of the Grotte Mandrin archeological project. Photo Dr Laure Metz.
View of the excavations at the entrace of Grotte Mandrin cave. Photo Ludovic Slimak.
Jason Lewis and archaeologist Pierre Andre in a nearby cave. Photo by Ludovic Slimak

By Daniel Dunaief

Two Stony Brook University researchers are helping a team of scientists rewrite the timeline of modern humans in Europe.

Prior to a ground breaking study conducted in the Rhône Valley in a cave called Grotte Mandrin in southern France, researchers had believed that homo sapiens — i.e. earlier versions of us — had arrived in Europe some time around 45,000 years ago.

Scientists had been studying the stone tools in this cave for close to 30 years that seemed inconsistent with the narrative that Neanderthals had exclusively occupied Europe at that point. Researchers found key evidence in this cave, including advanced tools and teeth that came from modern humans, that pushed the presence of modern humans back by about 10,000 years to about 56,800 years ago, while also indicating that the two types of humans interacted in the same place.

“This is a huge paradigm shift in our understanding of modern human origin expansion,” said Jason Lewis, a lecturer in the Department of Anthropology at Stony Brook University and Assistant Director at the Turkana Basin Institute in Kenya. “We can demonstrate that it was modern humans. We have a whole series of radiometric dates to shore that up 100 percent. Any method that was useful was applied” to confirm the arrival of homo sapiens in southern France.

Ludovic Slimak, CNRS researcher based at the University of Toulouse Jean Jaures, is the lead author on a 130-page paper that came out this week in Science Advances. Slimak has been exploring a site for 24 years that he describes as a kind of Neanderthalian Pompei, without the catastrophe of Mount Vesuvius erupting and preserving a record of the lives the volcano destroyed.

“This is a major turn, maybe one of the most important since a century,” Slimak explained in an email.

The early Homo sapiens travelers left behind clues about their presence in a rock shelter that alternately served as a home for Homo sapiens and Neanderthals in the same year.

“We demonstrate in our paper that there is less than a year, maybe a season (six months), maximal time between the last Neanderthal occupation in the cave and the first Sapiens settlement,” Slimak wrote. “This is a very, very short time!”

The scientists came to this conclusion after they developed a new way to analyze the soot deposits on the vault fragments of the cave roof, he added.

When modern humans arrived in the Rhône Valley, they likely turned to Neanderthals, who had occupied the area considerably longer, as scouts to guide them, Slimak suggested.

Homo sapiens likely traveled by boat to France at the same time that other Homo sapiens journeyed over the water to Australia, between 50,000 and 60,000 years ago.

“We know that when Mandrin groups reached western Europe, Eurasian populations perfectly master navigation at the other end of the continent,” Slimak explained in an email. “It is then very likely that these technologies were at this time period well known by all these populations.”

Different tools

In addition to fossils, scientists have focused on the tools that Homo sapiens produced and used. Homo sapiens likely used bows or spears with mechanical propulsion, while Neanderthals had heavy hand-cast spears, Slimak explained.

The modern human technology was “very impressive,” Slimak added. They are exactly the same technologies we found in the eastern Mediterranean at the very beginning of the Upper Paleolithic in the same chronology [as] the Grotte Mandrin.”

The tools were small and pointed and looked like the kind of arrowheads someone might find when hiking along trails on Long Island, Lewis described. “It’s never been suggested or demonstrated that Neanderthals made bows and arrows or complex projectiles,” he said.

Once they discovered teeth of Homo sapiens, the researchers found the conclusive fossil proof of “who was there doing this,” Lewis said. “Even on a baby tooth, you can distinguish Neanderthals from modern humans.”

While researchers have excavated other caves in the Middle Rhône Valley region, they have not used such stringent methods, Lewis explained. “Mandrin is truly unique for the vision it gives us into this period of the past,” he explained in an email. He described Mandrin as more of a rock shelter than a cave, which is about 10 meters wide and eight meters deep.

The importance of timing

With the importance of providing specific dates for these discoveries, scientists who specialize in ancient chronology, such as Marine Frouin, joined the team.

Frouin, who started working in the Grotte Mandrin in 2014 when she was a post-doctoral fellow at the Luminescence Laboratory at the University of Oxford, looks for the presence of radioactive elements like potassium, thorium and uranium to determine the age of sediments. When these elements decay, they emit radiation, which the sediments accumulate.

Frouin likened the build up of radioactive elements in the grains to the process of charging a battery. Over time, the radioactive energy increases, providing a signal for the last time sunlight reached the sediment.

Indeed, when the sun reaches these grains, it eliminates the signal, which means that Frouin collected samples in lower light, transported them to a lab or facility in darkness, and then analyzed them in rooms that look like a photographer’s darkroom studio.

Frouin conducted the first of three approaches to determining the timing for these discoveries. She used luminescence on quartz, feldspar and flint and was the first one to obtain dates in 2014. Colleagues at the Université de Paris then conducted Thermoluminescence dating on burnt flint, while the lab of Andaine Seguin-Orlando at the University Paul Sabatier Toulouse 3 provided single grain dating.

The three labs “were able to combine all our results together and propose a very precise chronology for this site with very high confidence,” she explained in an email.

Frouin, who arrived at Stony Brook University in January of 2020, has designed and built her own lab, where she plans to study samples and advance the field of luminescence dating.

At this point, luminescence dating can provide the timing from a few hundred years ago to 600,000 years, beyond which the radioactive signal reaches its maximum brightness. Trained as a physicist, Frouin, however, is developing new techniques to find larger doses from grains that data at least over a million years old.

Journey to France

During this period of time on the Earth, the climate was especially cold. That, Lewis said, would favor the continued use of the cave by Neanderthals, who could have survived better under more challenging conditions.

At around 55,000 years ago, however, something may have shifted in the modern human population that allowed Homo sapiens to survive in a colder climate. These changes could include projectile weapons, more advanced clothing and/or social cooperation.

“These are all hypotheses we are dealing with,” Lewis said. “In this case, it seems like a tentative exploration by modern humans into Western Europe.”

The cave itself would have been especially appealing to Neanderthals or modern humans because of its geographic and topological features. For scientists, some of those same features also helped provide a chronological record to indicate when each of these groups lived in that space.

Near the cave, the Rhône River provides a way to travel. The cave itself is situated at a bottleneck through which groups of migrating animals such as horse, bison and deer traveled to follow their own food sources.

“It’s one of the most strategic points in Southern France,” Lewis said.

Indeed, Allied Forces during World War II recognized the importance of this site, landing in Provence on August 15, 1944. The progression into Europe mirrored the expansion of modern humans, said Lewis, who studies history and is particularly interested in WWII.

The site faces northwest in a part of the Rhône Valley in which the mistral wind, which is a cold and dry strong wind, can reach up to speeds of 60 miles per hour. During the glacial period, the wind blew dust that came off the tundra of northern Europe, filling the cave with fine grain sediment that helped preserve the site. Using that dust, scientists determined that Neanderthals had occupied that cave for almost 100,000 years. Around 55,000 years ago, modern humans showed up, who were replaced again by Neanderthals.

A resident of Stony Brook, Lewis lives with his wife Sonia Harmand, who is in the same department at Stony Brook and with whom he has collaborated on research, and their daughter Scarlett.

A native of Dover, Pennsylvania, Lewis decided to study evolution after reading a coffee table book at a friend’s house when he was 13 that included descriptions of the work of the late paleoanthropologist Richard Leakey. After reading that book, Lewis said evolution made sense to him and he was eager to participate in the search for evidence of the changes that led to modern humans.

His first field experience was in a Neanderthal site in France, where he also traveled to the Turkana basin in Kenya for a project directed by Rutgers University. Ultimately, he wound up working for Rutgers and has conducted considerable research in Kenya as well.

“After working at Rutgers, I came to Stony Brook to work for [Richard Leakey in a field school at [what would become] the Turkana Basin Institute,” he said. The combination of his earlier aspirations to join Leakey, his first research field experiences including time in France and Kenya, and his eventual work with Leakey and his role at TBI were a part of his “circle of life.”

Lewis is thrilled to be a part of the ongoing effort to share information discovered in a cave he called a “magical place. The satisfaction at being there is high.”

For Slimak, the years of work at the site have been personally and professionally transformational. After taking necessary breaks from the rigors of excavating on the cave floor, he is now more comfortable sleeping on a hard floor than on a soft mattress.

Professionally, Slimak described this paper as the culmination of 32 years of continuous scientific efforts, which includes a “huge amount of very important unpublished data” that include social, cultural, economic and historical organization of these populations.

The current paper represents “only the visible part of the iceberg and many important enlightenment and other fascinating discoveries from my team will be made available in the coming months and years.”

A tough beginning

A native of Bordeaux, France, Frouin had a tough start to her work at Stony Brook. She arrived two months before the pandemic shut down many businesses and services, including driving schools and social security offices.

When she arrived, she didn’t have a driver’s permit or a credit history, which meant that she relied on the kindness and support of her colleagues and transportation from car services to pick up necessities like groceries.

A resident of Port Jefferson, Frouin, who enjoys playing electric guitar and does oil painting when she’s not studying sediments, said it took just under a year to get her American driver’s license.

Frouin, who has an undergraduate and a graduate student in her lab and is expecting to add another graduate student soon, appreciates the opportunity to explore the differences between the north and south shore of Long Island. 

As for her contribution to this work, she said this effort was “extremely exciting. I’m doing what I wanted to do since I was a kid. We were able to answer many questions that maybe 20 years ago, we weren’t able to answer.”

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R.C. Murphy College Team 1 in the Three Village School District took second place in the Middle School Division this year. Photo from BNL

Teams from Jericho Senior High School and Hunter College Middle School each won first place in the 2022 competitions hosted virtually by the U.S. Department of Energy’s Brookhaven National Laboratory on Friday, Jan. 28 and Saturday. Jan. 29. The tournament-style events quizzed students on a range of science disciplines including biology, chemistry, Earth science, physics, energy, and math.

Both teams will compete against regional winners from around the country in the National Science Bowl® this spring.  

“The National Science Bowl regional competitions provide students with an exciting introduction to the National Laboratory system and the Department of Energy,” said Amanda Horn, a Brookhaven Lab educator who coordinated the virtual events. “This contest gives students the opportunity to meet our scientists and support staff who volunteer as competition judges, introduce them to the laboratory’s cyber efforts through the Cyber Challenge and learn about future STEM opportunities available to them.”

As the top schools were called during the High School Science Bowl award ceremony on Jan. 28, Jericho students Hanson Xuan, Derek Minn, Ashwin Narayanan, Natasha Kulviwat, and Brendan Shek jumped up out of their chairs to celebrate.

“I am so surprised, and I am so proud of these people,” Kulviwat said. Team members said they studied up until the night before the competition, only adding to their weekly practices and time spent poring over textbooks in preparation for the big day.

“They worked so hard,” added Jericho coach Samantha Sforza. “They absolutely deserve this win.”

High School runners-up
Half Hollow Hills East High School captured second place this year in the High School Division. Photo from BNL

Second Place: Great Neck South High School – Jansen Wong, Matthew Tsui, Richard Zhuang, Jack Lenga, Eric Pei (Coaches: Nicole Spinelli, James Truglio)

Third Place: Half Hollow Hills East High School – Himani Mattoo, Daniel Salkinder, Dylan D’Agate, Jacob Leshnower, and Jeffin Abraham (Coach: Danielle Talleur)

Fourth Place: Ward Melville High School Team 1 – Ivan Ge, Gabriel Choi, Matthew Chen, Neal Carpino, Michael Melikyan (Coach: Silva Michel)

This year’s Middle School Science Bowl was open to New York City schools, and two teams from Hunter College Middle School earned First Place and Third Place.

“It’s really exciting,” said Devon Lee of Hunter College Middle School Team 1. “I’m just really proud of my team because they’re literally the coolest people I know.”

“Last year, we lost by two points,” added Morgan Lee. “Since I’m in eighth grade now I didn’t think we’d have a chance to come back from that and I’m glad that we did.”

The First Place team also included Segev Pri-Paz and Gabriel Levin. Hunter coach Min-Hsuan Kuo gave credit to high school students who helped the middle schoolers prepare.

“I always knew they would do great,” Kuo said. “We have a really wonderful situation in our school where our high school students are always working with younger students.”

Middle School runners-up

Second Place: R.C. Murphy College Middle School Team 1 –  Sahil Ghosh, Harry Gao, Willem VanderVelden, Gabrielle Wong, Kayla Harte (Coaches: Emily Chernakoff Jillian Visser)

Third Place: Hunter College Middle School Team 2 – Kavya Khandelwal, Kyle Wu, Melody Luo, Sophia Kim (Coach: Min-Hsuan Kuo)

Fourth Place: Paul J. Gelinas Jr. High School – Anna Xing, Tina Xing, Colby Medina, William Squire, Kyle McGarvey, (Coach: Monica Flanagan)

All participating students received a Science Bowl t-shirt. Winning teams will also receive trophies, and medals. The first-place high school and middle school teams will also receive a banner to hang at their schools. The top three high school teams will receive cash awards. Prizes were courtesy of Teachers Federal Credit Union and Brookhaven Science Associates (BSA), the event’s sponsors. BSA is the company that manages and operates Brookhaven Lab for DOE.

About 60 volunteers stepped up as virtual scorekeepers, judges, moderators, and support for the back-to-back events. For more information, visit https://energy.gov/science.

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Photo from Town of Smithtown
Photo from Town of Smithtown
Photo from Town of Smithtown
Photo from Town of Smithtown

The STEM Partnership between the Town of Smithtown and Smithtown School District continued at Accompsett Middle School, with sixth grade science students. On Thursday, January 27th and Friday January 28th, sixth grade science students in all eight classes met in the school’s library for an exciting water quality presentation and aquifer demonstration. The presentation covered a variety of environmental protection lessons, geared towards protecting

Long Island’s sole source aquifer. Students learned where Smithtown’s water comes from, threats to the natural resource, and how to protect the groundwater for future generations.

“This was the third topic covered as part of our STEM partnership with the school district and it was a huge success. The students were already very knowledgeable, asked very smart questions, and were so engaged that they didn’t want to leave, even after the bell rang for the next period. Further, we’ve already received calls from local civic groups requesting the presentation be given to adults within the community. What originally began as a unique real-world learning opportunity, has evolved into a larger movement, encouraging residents of all ages to be more proactive in caring for our natural resources and ecosystem.” – Supervisor Ed Wehrheim

The presentation began with asking students to discuss the water cycle, followed by where drinking water on Long Island comes from. A model demonstrating the Upper Glacial, Magothy, and Lloyd Aquifers, the famous layer of clay beneath the Magothy, water tables, natural streams, bodies of water and wastewater infrastructure was then used to illustrate how groundwater can become contaminated. The class was presented with a lesson on threats to our water supply, and emerging contaminants (PFOS,PFOA and 1 4 dioxane.) Worksheets listing household products containing harmful ingredients paired with a list of environmentally friendly alternatives, easily found in grocery stores were later distributed. Each teacher received digital copies of the worksheets, tips on how to help keep stormwater runoff from polluting waterways, and the 2022 recycling calendar which offers additional advice, a list of free services, and dates for the Hazardous Household Waste collection events to share at home

Plans for a second lesson in the Spring will involve nitrogen pollution, and natural remedies to stormwater runoff like Bioswales, which remove debris and pollution while preventing flooding. The recently completed Meadow Road Stormwater Remediation bioswale is located at the entrance to Accompsett Middle School, which will provide an excellent opportunity for students to observe Mother Nature’s solution to stormwater pollution.

The sixth grade water quality presentation was coordinated by Accompsett ELA/Science teacher Amy Olander, Director of Science K-12 Edward Casswell, Town Supervisor Ed Wehrheim and his office team; PIO Nicole Garguilo and Community Relations Assistant Brian Farrell. Expert support was provided by Environmental Director David Barnes, and Smithtown & St. James Water Superintendent Chris Nustad.

The STEM Partnership gives students a hands-on approach to real world environmental issues affecting the community. Students apply lesson plans in the branches of science to discover potential solutions. Topics covered in the program include solid waste & recycling, invasive species, stormwater runoff, nitrogen pollution and water quality. At every stage of the partnership, the Town and School district work in tandem to help students uncover solutions to each real world quandary. The Town of Smithtown hopes to expand this program to all local school districts who are interested in this unique learning opportunity.

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Suffolk County Vanderbilt Museum

The Suffolk County Vanderbilt Museum and Reichert Planetarium will reopen this weekend, Saturday and Sunday, February 5 to 6, from noon to 4:00 pm.

Starting Friday, February 11, the Vanderbilt will be open Friday through Sunday, 12 to 4 pm, and on Friday and Saturday nights for Planetarium shows at 8:00, 9:00, and 10:00. Masks are required inside all buildings.

On Saturday, February 5, the Planetarium will premiere a new show, Exoplanets: Discovering New Worlds. Visitors will be transported to planets orbiting faraway stars. Discovering exoplanets is one of today’s scientific goals, and finding life on those worlds is the next challenge.

Although science has not yet found evidence of alien life, this exciting program speculates on the existence of such life and explores how scientists are currently searching for exoplanets and their potential inhabitants. Recommended for ages 12 and up.Exoplanets will be showing Saturday afternoons at 3:00 pm from February 5 through March 20.

Another new Planetarium show that premiered recently is Explore, an odyssey to the planet Mars, seen through the lens of human history and scientific development. This visually stunning full-dome film begins with a look at how scholars and scientists throughout the ages used the sky as a clock and calendar to measure the passage of time. Their charts and star catalogs informed the modern science of astronomy.

Dave Bush, director of the Reichert Planetarium, called Explore “one of the finest productions ever made available to our audiences. It’s truly an immersive masterpiece.”

Explore is an adventurous journey from ancient Mesopotamia to modern space exploration. Experience the fascinating history of astronomy, geocentric and heliocentric models, the laws of planetary motion, and discover the principles of orbital maneuvers that enable satellites and space travel.

The museum is located at 180 Little Neck Road in Centerport. For more information, visit www.vanderbiltmuseum.org.

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Jason Trelewicz Photo from SBU

By Daniel Dunaief

One day, ships in the Navy may not only last longer in the harsh environment of salt water, but some of their more complicated parts may also be easier and quicker to fix.

That’s thanks to the mechanical engineering efforts of researchers at Stony Brook University and Brookhaven National Laboratory, who have been teaming up to understand the microstructural origins of corrosion behavior of parts they produce through laser additive manufacturing into shapes with complex geometries.

The Navy is funding research at the two institutions.

Eric Dooryhee. Photo from BNL

“As you would expect you’d need near any marine environment with salt water, [the Navy] is interested in laser additive manufacturing to enable the production of parts at lower cost that have challenging geometries,” said Jason Trelewicz, Associate Professor of Materials Science and Engineering at Stony Brook University. Additionally, the Navy is hoping that such efforts can enable the production of parts with specific properties such as corrosion resistance on demand.

“If you’re out at sea and something breaks, can you make something there to replace it?” asked Trelewicz. Ideally, the Navy would like to make it possible to produce parts on demand with the same properties as those that come off a manufacturing line.

While companies are currently adopting laser additive manufacturing, which involves creating three-dimensional structures by melting and resolidfying metal powders one layer at a time with the equivalent of a laser printer, numerous challenges remain for developing properties in printed materials that align with those produced through established routes.

Additive materials, however, offer opportunities to structure products in a way that isn’t accessible through traditional techniques that create more complex geometry components, such as complex heat exchangers with internal cooling channels.

In addition to the science remaining for exploration, which is extensive, the process is driving new discoveries in novel materials containing unique microstructure-chemistry relationships and functionally graded microstructures, Trelewicz explained.

“These materials are enabling new engineering components through expanded design envelopes,” he wrote in an email.

With colleagues from BNL including Research Associate Ajith Pattammattell and Program Manager for the Hard X-ray Scattering and Spectroscopy Program Eric Dooryhee, Trelewicz published a paper recently in the journal Additive Manufacturing that explored the link between the structure of the material and its corrosive behavior for 316L stainless steel, which is a corrosion resistant metal already in wide use in the Navy.

The research looked at the atomic and microstructure of the material built in the lab of Professor Guha Manogharan at Penn State University. Working with Associate Professor Gary Halada in the Department of Material Science and Chemical Engineering, Trelewicz studied the corrosive behavior of these materials.

Often, the surface of the material went through a process called pitting, which is common in steels exposed to corrosive environments, which occurs in cars driven for years across roads salted when it snows.

The researchers wanted to understand “the connection between how the materials are laser printed, what their micro structure is and what it means for its properties,” Trelewicz said, with a specific focus on how fast the materials were printed.

While the research provided some structural and atomic clues about optimizing anti corrosive behavior, the scientists expect that further work will be necessary to build more effective material.

In his view, the next major step is understanding how these defects impact the quality of this protective film, because surface chemical processes govern corrosive behavior.

Based on their research, the rate at which the surface corrodes through laser additive manufacturing is comparable to conventional manufacturing.

Printed materials, however, are more susceptible to attack from localized corrosion, or pitting. 

At the hard x-ray nanoprobe, Pattammattel explored the structure of the material at a resolution far below the microscopic level, by looking at nonstructural details.

“It’s the only functional beamline that is below 10 nanometers,” he said. “We can also get an idea about the electronic structures by using x-ray absorption spectroscopy,” which reveals the chemical state.

Pattammattel, who joined BNL in 2018, also uses the beamline to study how lung cells in mice interact with air pollutants. He described “the excitement of contributing to science a little more” as the best part of each day.

Meanwhile, Dooryhee as involved in writing the seed grant proposal. By using the x-rays deflected by the variety of crystalline domains or grains that compose the materials, HE can interpret the material’s atomic structure by observing the diffraction angles. The discrete list of diffraction angles is a unique fingerprint of the material that relates to its long-range atomic ordering or stacking.

In this study, researchers could easily recognize the series of diffraction peaks associated with the 316L stainless steel.

Dooryhee was able to gather insight into the grain size and the grain size distribution, which enabled him to identify defects in the material. He explained that the primary variable they explored was the sweeping rate of the laser beam, which included 550, 650 and 700 millimeters per second. The faster the printing, the lower the deposited energy density.

Ultimately, Dooryhee hopes to conduct so-called in situ studies, in which he examines laser additive manufacturing as it’s occurring.

“The strength of this study was to combine several synchrotron techniques to build a complete picture of the microstructure of the [additively manufactured] material, that can then be related to its corrosion response,” he explained in an email.

Dooryhee grew up in Burgundy France, where his grandfather used to grow wine. He worked in the vineyards during the fall harvest to help pay for his university studies. Dooryhee has worked at BNL for over 12 years and appreciates the opportunity to collaborate with researchers at Stony Brook University.

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