Mathematician named a Great Immigrant by Carnegie Corporation

Photo of Terence Tao

Terence Tao. Photo Credit: Reed Hutchinson

 

Terence Tao, professor of mathematics, who holds the James and Carol Collins Chair in the UCLA College, has been named by Carnegie Corporation of New York on its 2019 annual list of Great Immigrants — a salute to 38 naturalized citizens who “strengthen America’s economy, enrich our culture and communities, and invigorate our democracy through their lives, their work, and their examples.”

Tao became the first mathematics professor in UCLA history to be awarded the Fields Medal in 2006, often described as the “Nobel Prize in mathematics.” He has earned many other honors, including the National Science Foundation’s Alan T. Waterman Award, the Breakthrough Prize in Mathematics, Royal Society’s 2014 Royal Medal for physical sciences and the Royal Swedish Academy of Sciences’ Crafoord Prize. National Geographic magazine featured him in its “What makes a genius?” May 2017 issue.

Every Fourth of July since 2006, the Carnegie Corporation of New York has sponsored the public awareness initiative to commemorate the legacy of its founder, Scottish immigrant Andrew Carnegie, who believed strongly in both immigration and citizenship.

“As we celebrate these 38 extraordinary individuals, we are reminded of the legacy of our founder, Andrew Carnegie, who showed the country how immigrants contribute to the great, unfinished story that is America,” said Vartan Gregorian, president of Carnegie Corporation of New York.

This article originally appeared in the UCLA Newsroom.

Professor’s latest book examines the history of cities

Photo of Monica Smith

Monica Smith. Photo credit: Paul Connor

The only thing a person really needs to be an archaeologist is a good sense of observation, UCLA professor of anthropology Monica Smith proclaims in her most recent book, “Cities: The First 6,000 Years.”

Advanced degrees and research experience are useful of course, but successful fieldwork is rooted in “noticing,” she said.

Archaeologists are always looking down noticing traces of what’s been left behind, and the stories detritus can tell, she said. These days at UCLA that might mean traces of glitter bombs launched by graduates during the last several weeks.

“We walk along and there’s all this glitter on the ground, and even though it gets cleaned away, you can never get it all so then you start to see little traces of glitter everywhere, because people are tracking it on their shoes all around campus,” Smith said. “We’re not only walking through an archaeological site, we’re making one.”

Smith is amused at the thought of future archaeologists encountering and interpreting the meaning behind those trace elements of shimmer in the dust around this particular area in one of Earth’s largest cities.

In vivid style, Smith’s latest book examines ways in which human civilization has organized itself into city life during the last 6,000 years, a relatively short time span in the grand scheme of human existence. Today, more than half of the world’s population resides in cities, and that number will continue to grow. But that wasn’t always so.

In “Cities,” Smith tracks the ways metropolitan hubs in different parts of the world emerged unrelated to one another, but in eerily similar forms, revealing the inherent similarities of humans’ needs regardless of what part of the world their civilization evolved.

“I started asking myself, ‘Why do these places all look the same even though they’re different times, different areas, different cultures and different languages?’” she said. “What is it about our human cognitive capacity that leads us to have the same form over and over and over again?”

She imagines how the first Spanish warriors to arrive in Cuzco in Peru, or Tenochtitlan in present day Mexico City, encountered the layout of ancient Inca and A

ztec cities, with shops and open squares and marketplaces resembling what they would see at home — despite the cultures never having had contact before.

“The similarities suggest that humans developed cities because it was the only way for a large number of people to live together in a single place where they could all get something new they wanted, whether that was a job, entertainment, medical care or education,” Smith said.

For the purposes of her analysis, Smith defines a city as a place with a dense population of multiple ethnicities; a diverse economy with an abundant variety of readily available goods; buildings and spaces of religion or ritual; a vertical building landscape that encompasses residential homes, courts, schools and government offices; formal entertainment venues; open grounds and multipurpose spaces; broad avenues and thoroughfares for movement.

Before cities, the human population was scattered across larger agrarian swaths, with families having everything they needed to survive in their own homes. People would come together for trading festivals or sacred ceremonies. These most likely began to last longer and longer, Smith said, creating a permanent collective settlement around places conducive to providing food, water, shelter and entertainment. Humans essentially took the bold step of living away from their immediate food supply to live in cities among larger groups of other humans.

Takeout food vendors have been a staple of cities stretching about as far back as you can get, with evidence of takeout food in ancient cities like Pompeii and Angkor, Smith notes in her book.

And cities allowed for the evolution of all kinds of new jobs and enterprises — bookkeeping, the service industry and managers — constituting a newly emergent middle class that found new opportunities to thrive in dense populations.

Some aspects of city life accelerated long-standing tendencies. Humans are a unique species in the animal kingdom due to our deep dependence on objects, a fact that aids archeologists in their work of noticing. Ancient cities also struggled with some of the same things we do in modern times — trash for example, Smith said.

“We think of ourselves as bad modern people because we have all this trash,” Smith said. “But everyone everywhere has trash. Ancient cities are full of trash. Modern cities are full of trash because people want more stuff.”

Archaeologists are obsessed with trash, Smith said. They learn much and encounter new questions from what was considered disposable to our ancestors.

Smith’s book also offers a descriptive window into day-to-day life on an archaeological dig, sharing challenges and the excitement of new technologies that help identify potential dig sites. People working to excavate subway tunnels and building foundations in modern Athens, Rome, Mexico City, Istanbul, Paris and other places are constantly finding new evidence of these metropolises’ earliest incarnations.

Much like current generations of young adults and children who cannot imagine a world without the internet, cities are here to stay, Smith said.

“From this point forward, there is no way that humans can live without urbanism, there is no ‘going back to the land,’” she said. “We can take a sort of comfort in the fact that the challenges we face like infrastructure, transportation, water sourcing, pollution and trash have essentially been a part of city life from the very beginning.”

Smith said one of the goals of her writing is to inspire people to think of cities as dynamic and adaptable.

“We can work to make cities not only more efficient, but more equitable, in the sense of social justice and greater opportunities for larger numbers of people, along with greater diversity,” she said. “Cities are not just inherited configurations, but are places with potential for growing into the better societies that we wish for ourselves and others.”

This article originally appeared in the UCLA Newsroom.

4d graphic rendering of iron-platinum nanoparticle

Atomic motion is captured in 4D for the first time

4d graphic rendering of iron-platinum nanoparticle

The image shows 4D atomic motion captured in an iron-platinum nanoparticle at three different times.
Credit: Alexander Tokarev

Results of UCLA-led study contradict a long-held classical theory

Everyday transitions from one state of matter to another — such as freezing, melting or evaporation — start with a process called “nucleation,” in which tiny clusters of atoms or molecules (called “nuclei”) begin to coalesce. Nucleation plays a critical role in circumstances as diverse as the formation of clouds and the onset of neurodegenerative disease.

A UCLA-led team has gained a never-before-seen view of nucleation — capturing how the atoms rearrange at 4D atomic resolution (that is, in three dimensions of space and across time). The findings, published in the journal Nature, differ from predictions based on the classical theory of nucleation that has long appeared in textbooks.

“This is truly a groundbreaking experiment — we not only locate and identify individual atoms with high precision, but also monitor their motion in 4D for the first time,” said senior author Jianwei “John” Miao, a UCLA professor of physics and astronomy, who is the deputy director of the STROBE National Science Foundation Science and Technology Center and a member of the California NanoSystems Institute at UCLA.

Research by the team, which includes collaborators from Lawrence Berkeley National Laboratory, University of Colorado at Boulder, University of Buffalo and the University of Nevada, Reno, builds upon a powerful imaging techniquepreviously developed by Miao’s research group. That method, called “atomic electron tomography,” uses a state-of-the-art electron microscope located at Berkeley Lab’s Molecular Foundry, which images a sample using electrons. The sample is rotated, and in much the same way a CAT scan generates a three-dimensional X-ray of the human body, atomic electron tomography creates stunning 3D images of atoms within a material.

Miao and his colleagues examined an iron-platinum alloy formed into nanoparticles so small that it takes more than 10,000 laid side by side to span the width of a human hair. To investigate nucleation, the scientists heated the nanoparticles to 520 degrees Celsius, or 968 degrees Fahrenheit, and took images after 9 minutes, 16 minutes and 26 minutes. At that temperature, the alloy undergoes a transition between two different solid phases.

Although the alloy looks the same to the naked eye in both phases, closer inspection shows that the 3D atomic arrangements are different from one another. After heating, the structure changes from a jumbled chemical state to a more ordered one, with alternating layers of iron and platinum atoms. The change in the alloy can be compared to solving a Rubik’s Cube — the jumbled phase has all the colors randomly mixed, while the ordered phase has all the colors aligned.

In a painstaking process led by co-first authors and UCLA postdoctoral scholars Jihan Zhou and Yongsoo Yang, the team tracked the same 33 nuclei — some as small as 13 atoms — within one nanoparticle.

“People think it’s difficult to find a needle in a haystack,” Miao said. “How difficult would it be to find the same atom in more than a trillion atoms at three different times?”

The results were surprising, as they contradict the classical theory of nucleation. That theory holds that nuclei are perfectly round. In the study, by contrast, nuclei formed irregular shapes. The theory also suggests that nuclei have a sharp boundary. Instead, the researchers observed that each nucleus contained a core of atoms that had changed to the new, ordered phase, but that the arrangement became more and more jumbled closer to the surface of the nucleus.

Classical nucleation theory also states that once a nucleus reaches a specific size, it only grows larger from there. But the process seems to be far more complicated than that: In addition to growing, nuclei in the study shrunk, divided and merged; some dissolved completely.

“Nucleation is basically an unsolved problem in many fields,” said co-author Peter Ercius, a staff scientist at the Molecular Foundry, a nanoscience facility that offers users leading-edge instrumentation and expertise for collaborative research. “Once you can image something, you can start to think about how to control it.”

The findings offer direct evidence that classical nucleation theory does not accurately describe phenomena at the atomic level. The discoveries about nucleation may influence research in a wide range of areas, including physics, chemistry, materials science, environmental science and neuroscience.

“By capturing atomic motion over time, this study opens new avenues for studying a broad range of material, chemical and biological phenomena,” said National Science Foundation program officer Charles Ying, who oversees funding for the STROBE center. “This transformative result required groundbreaking advances in experimentation, data analysis and modeling, an outcome that demanded the broad expertise of the center’s researchers and their collaborators.”

Other authors were Yao Yang, Dennis Kim, Andrew Yuan and Xuezeng Tian, all of UCLA; Colin Ophus and Andreas Schmid of Berkeley Lab; Fan Sun and Hao Zeng of the University at Buffalo in New York; Michael Nathanson and Hendrik Heinz of the University of Colorado at Boulder; and Qi An of the University of Nevada, Reno.

The research was primarily supported by the STROBE National Science Foundation Science and Technology Center, and also supported by the U.S. Department of Energy.

This story originally appeared in the UCLA Newsroom.

Photo of baby laughing

Babies Know the Difference between the Laughter of Friends and Strangers

Five-month-olds may use chuckles to identify information about social interactions

Photograph of baby laughing

Credit: Aarti Kalyani Getty Images

Most people can share a laugh with a total stranger. But there are subtle—and detectable—differences in our guffaws with friends.

Greg Bryant, a cognitive scientist at the University of California, Los Angeles, and his colleagues previously found that adults from 24 societies around the world can distinguish simultaneous “co-laughter” between friends from that between strangers. The findings suggested that this ability may be universally used to help read social interactions. So the researchers wondered: Can babies distinguish such laughter, too?

Bryant and his fellow researcher Athena Vouloumanos, a developmental psychologist at New York University, played recordings of co-laughter between pairs of either friends or strangers to 24 five-month-old infants in New York City. The babies listened longer to the laughs shared between buddies—suggesting they could tell the two types apart, according to a study published in March in Scientific Reports.

The researchers then showed the babies short videos of two people acting either like friends or strangers and paired those with the audio recordings. The babies stared for longer at clips paired with a mismatched recording—for example, if they saw friends interacting but heard strangers laughing.

“There’s something about co-laughter that is giving information to even a five-month-old about the social relationship between the individuals,” Bryant says. Exactly what components of laughter the infants are detecting remains to be seen, but prior work by Bryant’s team provides hints. Laughs between friends tend to include greater fluctuations in pitch and intensity, for example.

Such characteristics also distinguish spontaneous laughs from fake ones. Many scientists think unprompted laughter most likely evolved from play vocalizations, which are also produced by nonhuman primates, rodents and other mammals. Fake laughter probably emerged later in humans, along with the ability to produce a wide range of speech sounds. The researchers suggest that we may be sensitive to spontaneous laughter during development because of its long evolutionary history.

“It’s really cool to see how early infants are distinguishing between different forms of laughter,” says Adrienne Wood, a psychologist at the University of Virginia, who was not involved in the study. “Almost every waking moment is a social interaction for [babies], so it makes sense that they are becoming very attuned to their social worlds.”

This story originally appeared in the Scientific American.

Andrea Ghez, Lauren B. Leichtman & Arthur E. Levine Chair in Astrophysics at UCLA, receiving an honorary doctorate from Oxford University on June 26, 2019. Ghez is with her sons.

UCLA astronomer receives honorary degree from Oxford

By Lisa Garibay

Andrea Ghez, Lauren B. Leichtman & Arthur E. Levine Chair in Astrophysics at UCLA, receiving an honorary doctorate from Oxford University on June 26, 2019. Ghez is with her sons.

UCLA’s Andrea Ghez with her sons at Oxford University.

Andrea Ghez, distinguished professor of physics and astronomy and director of UCLA’s Galactic Center Group, was awarded an honorary degree today from Oxford University during its annual Encaenia ceremony.

Ghez demonstrated the existence of a supermassive black hole at the center of our galaxy, with a mass 4 million times that of our sun. Her work provided the best evidence yet that these exotic objects really do exist, providing an opportunity to study the fundamental laws of physics in the extreme environment near a black hole, and learn what role this black hole has played in the formation and evolution of our galaxy.

She joins an eclectic group including cellist Yo-Yo Ma, Nobel laureate Daniel Kahneman, and UC Berkeley professor Jennifer Doudna, who developed the CRISPR-Cas9 technology for gene editing.

Ghez, who is the Lauren B. Leichtman & Arthur E. Levine Chair in Astrophysics, earned her bachelor’s degree in physics from MIT in 1987 and her doctorate from Caltech in 1992, and has been on the faculty at UCLA since 1994.

This article was originally published on the UCLA Newsroom.

New simulations suggest that carbon (C) routinely bonded with iron (Fe), silicon (Si) and oxygen (O) deep within the magma ocean that covered Earth when it was young.

New insights about carbon and ice could clarify inner workings of Earth, other planets

New simulations suggest that carbon (C) routinely bonded with iron (Fe), silicon (Si) and oxygen (O) deep within the magma ocean that covered Earth when it was young.

New simulations suggest that carbon (C) routinely bonded with iron (Fe), silicon (Si) and oxygen (O) deep within the magma ocean that covered Earth when it was young.

 

Most people behave differently when under extreme pressure. Carbon and ice are no different.

Two new studies show how these key planetary ingredients take on exotic forms that could help researchers better understand the composition of Earth’s core as well as the cores of planets across the galaxy. Craig Manning, a UCLA professor of geology and geochemistry, is a co-senior author of one of the papers, which was published today in the journal Nature, and senior author of the other, which was published in Nature Communications in February.

The Nature Communications paper revealed that high pressure deep inside the young Earth may have driven vast stores of carbon into the planet’s core while also setting the stage for diamonds to form. In the Nature report, researchers found that water ice undergoes a complex crystalline metamorphosis as the pressure slowly ratchets up.

Scientists have long understood that the amount of carbon sequestered in present-day Earth’s rocks, oceans and atmosphere is always in flux because the planet shuffles the element around in a vast cycle that helps regulate climate. But researchers don’t know whether the Earth locked away even more carbon deep in its interior during its formative years — information that could reveal a little more about how our planet and others like it are built.

To pursue an answer to that question, Manning and colleagues calculated how carbon might have interacted with other atoms under conditions similar to those that prevailed roughly 4.5 billion years ago, when much of Earth was still molten. Using supercomputers, the team created simulations to explore what would happen to carbon at temperatures above 3,000 degrees Celsius (more than 5,400 degrees Fahrenheit) and at pressures more than 100,000 times of those on Earth’s surface today.

The experiment revealed that under those conditions, carbon tends to link up with iron, which implies that there might be considerable quantities of carbon sealed in Earth’s iron core today. Researchers had already suspected that in the young planet’s magma ocean, iron atoms hooked up with one another and then dropped to the planet’s center. But the new research suggests that this molten iron rain may have also dragged carbon down with it. Until now, researchers weren’t even sure whether carbon exists down there.

The team also found that as the pressure ramps up, carbon increasingly bonds with itself, forming long chains of carbon atoms with oxygen atoms sticking out.

“These complex chains are a form of carbon bonding that we really hadn’t anticipated at these conditions,” Manning said.

Such molecules could be a precursor to diamonds, which consist of many carbon atoms linked together.

Solving an icy enigma

The machinations of carbon under pressure provide clues as to how Earth-like planets are built. Frozen planets and moons in other solar systems, however, may also have to contend with water ice. In a separate paper, Manning and another team of scientists looked at how the molecular structure of extremely cold ice changes when put under intense pressure.

Under everyday conditions, water ice is made up of molecules laid out in honeycomb-like mosaics of hexagons. But when ice is exposed to crushing pressure or very low temperature — in labs or possibly deep inside remote worlds — the molecules can assume a bewildering variety of patterns.

One of those patterns, known as amorphous ice, is an enigma. In amorphous ice, the water molecules eschew rigid crystalline order and take on a free-form arrangement. Manning and colleagues set out to try and understand how amorphous ice forms.

First, they chilled normal ice to about 170 degrees below zero Celsius (about 274 degrees below zero Fahrenheit). Then, they locked the ice in the jaws of a high-tech vice grip inside a cryogenic vacuum chamber. Finally, over the span of several hours, they slowly stepped up the pressure in the chamber to about 15,000 times atmospheric pressure. They stopped raising the pressure periodically to fire neutrons through the ice so that they could see the arrangement of the water molecules.

Surprisingly to the researchers, the amorphous ice never formed. Instead, the molecules went through a series of previously known crystalline arrangements.

However, when the researchers conducted the same experiment but raised the pressure much more rapidly — this time in just 30 minutes — amorphous ice formed as expected. The results suggest that time is the secret ingredient: When pressure increases slowly, tiny seeds of crystalline ice have time to form and take over the sample. Otherwise, those seeds never get a chance to grow.

The findings, published May 23 in the journal Nature, could be useful to researchers who study worlds orbiting other suns and are curious about what conditions might be like deep inside frozen planets.

“It’s entirely likely that there are planets dominated by ice in other solar systems that could obtain these pressures and temperatures with ease,” Manning said. “We have to have this right if we’re going to have a baseline for understanding the interiors of cold worlds that may not be like Earth.”

Both papers were funded in part by the Deep Carbon Observatory, a 10-year program started in 2009 to investigate the quantities, movements, forms and origins of deep carbon inside Earth. The Nature Communications paper was also funded by the European Research Council and was co-authored by researchers at the Ecole Normale Supérieure de Lyon in France, one of whom — Natalia Solomatova — completed her undergraduate studies at UCLA. The Nature paper was co-authored by UCLA geologist Adam Makhluf and researchers from Oak Ridge National Laboratory and the National Research Council of Canada.

This article originally appeared on the UCLA Newsroom.

 

Jo Anne Van Tilburg, right, and Cristián Arévalo Pakarati

The stone faces and human problems on Easter Island

Excavation of Moai 156 (left) and 157. The visible difference in color and texture, and thus in preservation, is due to soil and depth coverage.

Excavation of Moai 156 (left) and 157. The visible difference in color and texture, and thus in preservation, is due to soil and depth coverage.

Archaeologist Jo Anne Van Tilburg continues to seek insight from the statues and for the living descendants of their makers

In 1981, UCLA archaeology graduate student Jo Anne Van Tilburg first set foot on the island of Rapa Nui, which is commonly called Easter Island, eager to explore her interest in rock art by studying the iconic stone heads that enigmatically survey the landscape.

Van Tilburg was one of just a few thousand people who would visit Rapa Nui each year back then. And though the island to this day remains one the most remote inhabited islands in the world, a surge in annual visitors has placed its delicate ecosystem and archaeological treasures in jeopardy.

“When I went to Easter Island for the first time in ’81, the number of people who visited per year was about 2,500,” said Van Tilburg, director of the Easter Island Statue Project, the longest collaborative artifact inventory ever conducted on the Polynesian island that belongs to Chile. “As of last year the number of tourists who arrived was 150,000 from around the world.”

On April 21, which is Easter Sunday, CBS’ “60 Minutes” will air a special interview with Van Tilburg and Anderson Cooper filmed on the island, talking about efforts to preserve the moai (pronounced MO-eye) — the monolithic stone statues that were carved and placed on the island from around 1100 to 1400 and whose stoic faces have fascinated the world for decades.

Jo Anne Van Tilburg, right, and Cristián Arévalo Pakarati

Jo Anne Van Tilburg, right, and Cristián Arévalo Pakarati

Back in 2003, Van Tilburg, who is research associate at the UCLA Cotsen Institute of Archaeology and director of UCLA’s Rock Art Archive since 1997, was the first archaeologist since the 1950s to obtain permission from Chile’s National Council of Monuments and the Rapa Nui National Park, with the Rapa Nui community and in collaboration with the National Center of Conservation and Restoration, Santiago de Chile, to excavate the moai, which most people didn’t know included torsos, which are buried below the surface, prior to her work and the publicity surrounding it.

Her success in obtaining permission to dig on the island, she credits to a philosophy of “community archaeology.” She has spent nearly four decades among the people of Rapa Nui, listening, learning, making connections, making covenants with the elders of the society, reporting extensively on her findings. Major funding has been provided by the Archaeological Institute of America Site Preservation Fund.

“I think my patience and diligence was rewarded,” she said. “They saw me all those years getting really dirty doing the work. What they don’t like is when people come and think they have all the answers and then leave. That feels to the Rapanui like their history is being co-opted.”

Van Tilburg credits the sustained and generous support of UCLA’s Cotsen Institute as critical to her continued work on the island. She has also made it a point to include UCLA undergraduates from a variety of academic disciplines in the hands-on work on Rapa Nui, including Alice Hom who began as a work study student 20 years ago and who now serves as project manager for the Easter Island Statue Project.

Van Tilburg, who received her doctorate in archaeology from UCLA in 1989, is working on a massive book project harnessing her vast archive that will serve as an academic atlas of the island, its history and the meaning behind the moai. She used the proceeds of a previous book to invest in a local business, the Mana Gallery and Mana Gallery press, both of which highlight indigenous artists. And she helped the local community rediscover their canoe-making history through the 1995 creation of the Rapa Nui Outrigger Club.

Jo Anne Van Tilburg being interviewed by Anderson Cooper of “60 Minutes”

Jo Anne Van Tilburg being interviewed by Anderson Cooper of “60 Minutes”

Her co-director on the Easter Island Statue Project, Cristián Arévalo Pakarati, is Rapanui and a graphic artist by trade. Van Tilburg exclusively employs islanders for her excavation work. She’s traveled the world helping catalog items from the island that are now housed in museums like the Smithsonian in Washington, D.C., and the British Museum in London. Van Tilburg does this to assist repatriation efforts.

Rapa Nui is more commonly known as Easter Island because Dutch explorer Jacob Roggeveen first landed there on Easter Sunday, April 5, 1722. But the people who already lived there (Polynesian descendants of a massive human migration more than 500 years earlier), simply called the place “home,” Van Tilburg said.

“Very few pacific islands originally had names,” Van Tilburg said. “What was named was a landmark or a star or something that brought you to it, but not necessarily the island itself.”

The “60 Minutes” interview also focuses on how current residents of the island are coping with increasing waves of tourism, which is almost always a double-edged sword, but is especially so in a fragile ecosystem, Van Tilburg said.

The now 150,000 annual visitors pale in comparison to the vast numbers of travelers who flock to Egypt’s pyramids and awe-inspiring archaeological sites, she noted.

The intricate rock art on the back of Moai 157.

The intricate rock art on the back of Moai 157.

“But by Rapa Nui standards, on an island where electricity is provided by a generator, water is precious and depleted, and all the infrastructure is stressed, 150,000 is a mob,” she said.

What’s more disheartening is the frequent disrespectful nature of some travelers who ignore the rules and climb on the moai, trample preserved spaces and sit on top of graves all in service of getting a photo of themselves picking the nose of an ancient artifact, Van Tilburg said.

The masses and the increasingly harmful glibness of the travelers are something the 5,700 residents of the island must grapple with. Only in the last decade or so have they been given governance of the national park where the moai are located. In 1995, UNESCO named Easter Island a World Heritage Site, with much of the island protected within Rapa Nui National Park.

Van Tilburg’s original impetus behind studying the moai is rooted in her curiosity about migration, marginalized people and how societies rise and fall.

“Rapa Nui was the last island settled probably in the whole westward movement that took place from southeast Asia across the Pacific,” Van Tilburg said. “I’m interested in what that might signal to us about today and why people are moving around the world the way they are.”

Rapanui society was traditionally hierarchical, led by a class of people who believed themselves God-appointed elites. These leaders dictated where the lower classes could live, how they would work to provide food for the elites and the population at large. The ruling class also determined how and when the moai would be built as the backdrop for exchange and ceremony.

“This inherently institutionalized religious hierarchy produced an inequitable society,” Van Tilburg said. “They were very successful in the sense that their population grew and they were good horticulturists, agriculturists and fisherman. But they were unsuccessful at understanding that unless they managed what they had better, and more fairly, that there was no future.”

Population growth and rampant inequity in a fragile environment eventually led to wrenching societal changes, she said. Internal collapse (as outlined in UCLA professor Jared Diamond’s book “Collapse”) along with colonization and slave-trading in the 1800s caused the population of Rapa Nui to drop to just 111 in the 1870s.

As an anthropologist, Van Tilburg is deeply interested in equity.

“I’m interested in asking why do we keep replicating societies in which people are not equal, because in doing so, we initiate a crisis,” she said. “Inequity is at the heart of our human problems.”

This story originally appeared in the UCLA Newsroom.

Photo of UCLA professor Kent Hill and graduate student Stephanie DeMarco

Scientists identify a key gene in the transmission of deadly African sleeping sickness

Photo of UCLA professor Kent Hill and graduate student Stephanie DeMarco

Research by UCLA professor Kent Hill and graduate student Stephanie DeMarco, as well as colleagues at the University of Bern, could lead to new approaches to treat African sleeping sickness.

 

Life scientists from UCLA and the University of Bern have identified a key gene in the transmission of African sleeping sickness — a severe disease transmitted by the bite of infected tsetse flies, which are common in sub-Saharan Africa.

The disease is fatal if untreated, as the parasite responsible moves from the bloodstream to the central nervous system. Tens of millions of people in 36 African countries are at risk. There is no vaccine, and conventional drug treatments, which include an arsenic derivative, are antiquated, not very effective and have severe side effects.

The research, published in the journal Nature Communications, could lead to new approaches to treat the disease. It also provides scientists with the first detailed understanding of how the parasite moves through the fly and what genes enable it to do so.

The tiny, single-celled parasite that causes African sleeping sickness in humans, and debilitating diseases in other mammals, is called Trypanosoma brucei, or T. brucei. To become infectious, the parasite must travel through tissues of the fly, from the midgut to the salivary gland — and then into the human or other animal, through a bite.

In the study, Stephanie DeMarco, a UCLA graduate student in molecular biology, and Sebastian Shaw, a graduate student at Switzerland’s University of Bern, worked with two sets of the T. brucei parasite. In one set, they made a mutation in one of the parasite’s genes, called phosphodiesterase-B1, or PDEB1.

Then, they infected 2,000 tsetse flies with some 20,000 parasites each — half of the flies received blood containing normal T. brucei parasites and the other half received blood with the mutated versions.

When tsetse flies drink infected blood, the parasites from the blood typically travel to the midgut and then into a tissue closer to the head, called the proventriculus, before moving on to the salivary glands.

But the researchers saw a striking difference in the proventriculus between the two sets of flies. Among the flies that received the normal parasites, those that had parasites in the gut also had parasites in the proventriculus; but among the 1,000 flies that received mutant T. brucei, only a single one that had parasites in the gut also had a parasite in the proventriculus.

“The normal parasites were able to get to the proventriculus just fine, but for the mutants, we saw only one lonely parasite swimming around,” DeMarco said. “That told us that phosphodiesterase-B1 is really important for the parasites to move from the fly midgut to the proventriculus.”

Shaw said, “When we saw the huge difference between the mutants and normal parasites, at first we couldn’t believe it.”

Kent Hill, a UCLA professor of microbiology, immunology and molecular genetics, and one of the study’s senior authors, said the findings also suggested that there must be a barrier preventing the mutants from getting from the midgut to the proventriculus.

To learn where that barrier is, the scientists made fluorescent parasites and fed the flies a fluorescent dye that stained different tissues in the fly different colors, enabling the researchers to track the parasites.

To go from the midgut to the proventriculus, the parasites have to cross the peritrophic matrix, a sheet-like structure produced by the proventriculus that protects the midgut.

“We found the normal parasites could get through the peritrophic matrix just fine, but the mutants were mostly stuck on one side of it,” DeMarco said.

That finding indicated that the peritrophic matrix was the barrier the scientists were looking for.

The research identifies for the first time the genes that enable the parasites to sense where they are and allow them to survive their journey in fly tissues; those mechanisms had not been understood well until now.

“We think the way the parasites perceive where they are may be similar in the tsetse flies and in mammals — including humans — as they go through barriers and tissues,” said co-senior author Isabel Roditi, a University of Bern professor. “If so, there could potentially be a new drug that might disrupt their ability to do that.”

The researchers also uncovered another clue to African sleeping sickness: In parasites with mutated PDEB1, there was a dramatic increase in the number of cyclic AMP molecules, signaling molecules that play an important role in the disease.

Normal parasites are social and coordinate their behavior, DeMarco said. But the research revealed that without PDEB1, the parasites have too much cyclic AMP in their cells and can’t communicate with one another.

“When Sebastian and Stephanie got rid of PDEB1, the parasites got flooded with cyclic AMP,” Hill said. “Then, when the signal came in telling the parasites, ‘You’re in the stomach and you need to move,’ they couldn’t hear the sound. That’s what we think the problem is for the mutant parasites.”

Hill said the new insights from the UCLA–Bern study could apply to other disease-causing parasites as well. For example, T. brucei parasites are related to parasites found in the U.S. and elsewhere that cause Chagas disease, in which parasites invade heart tissue, leading to inflammation and enlarged heart tissue, and in some cases, heart failure.

Hill’s research is funded by the National Institutes of Health’s National Institute of Allergy and Infectious Diseases and the National Institute of General Medical Sciences. Roditi’s research is funded by the Swiss National Science Foundation and the Howard Hughes Medical Institute.

Photo of Brenda Elaine Stevenson

Brenda Elaine Stevenson receives inaugural 2019 Germany residency at the University of Augsburg

Photo of Brenda Elaine Stevenson

Brenda Elaine Stevenson

During its annual meeting in Philadelphia, Pennsylvania, the Organization of American Historians (OAH) announced that Brenda Elaine Stevenson, University of California, Los Angeles, has been selected to receive the inaugural 2019 residency at the University of Augsburg.

 

2019 Germany Residency Program
Thanks to a generous grant from the Fritz Thyssen Foundation, the OAH is pleased to continue the Germany Residency Program in American history at the University of Tübingen. Funding from the University of Augsburg will also enable an extension of the program to the University of Augsburg in 2019. The resident scholar at each university will offer a seminar on a U.S. history topic of his or her design.

The residency was announced on April 5 by OAH’s 2019–20 President Joanne Meyerowitz.

 

About the Organization of American Historians
Founded in 1907, the Organization of American Historians (OAH) is the world’s largest professional association dedicated to American history scholarship. With more than 7,500 members from the U.S. and abroad, OAH promotes excellence in the scholarship, teaching, and presentation of American history, encouraging wide discussion of historical questions and equitable treatment of history practitioners. It publishes the quarterly Journal of American History, the leading scholarly publication and journal of record in the field of American history for more than a century. It also publishes The American Historian magazine. Formerly known as the Mississippi Valley Historical Association (MVHA), the association became the OAH in 1965 to reflect a broader scope focusing on national studies of American history. The OAH national headquarters are located in the historic Raintree House on Indiana University’s Bloomington campus.

Photo of Professor Stephanie Jamison.

Professor Stephanie Jamison to share how she finds women in ancient, often patriarchal, texts

Photo of Professor Stephanie Jamison.

Stephanie Jamison

For four decades, UCLA’s Stephanie Jamison has been somewhat defiantly seeking the stories of women among some of the oldest texts in the world. Jamison’s expertise lies in Indo-Iranian, especially Sanskrit and middle Indo-Aryan languages with an emphasis on linguistics, literature and poetics, religion and law, mythology and ritual, and gender.

Jamison will share some of what she has unearthed on April 3 as she delivers UCLA’s 126th Faculty Research Lecture titled “Looking for Women Between the Lines in Ancient India.” They will be names and stories of women we have likely never heard of before.

“It is often said that the kind of scholarship that I do, which is very traditional examination of written language, cannot be used to study women and marginal groups, because it’s just not there,” said Jamison, distinguished professor of Asian languages and cultures and also Indo-European studies in the UCLA College.

But Jamison would argue that the tools employed through traditional philology (the study of language in literary texts and other written records) are actually well suited for digging beneath the surface of text for exactly those stories, even among the works from colonialist and patriarchal cultures.

Even back as far as 1500 B.C. in India.

For 15 years, Jamison and her co-author Joel Brereton worked on a translation of the “Rig Veda,” India’s oldest Sanskrit text. Published in 2014, theirs is the first full English translation in well over a century of the text that is considered crucial to the understanding both of Indo-European and Indo-Iranian cultural prehistory and of later Indian religious history and high literature.

It’s an era and a place that essentially has no archaeology to help interpret meaning, so we are completely dependent upon text for context, Jamison said. She often summarizes philology as the work of “text and context.”

“In the Rig Veda there was a debate going on underneath the surface about the place of women in religious life,” Jamison said. “There are very enigmatic snatches of narrative about women or female goddesses or demigoddess and they are being deployed by two different sides of the debate as examples of either the terrible or wonderful things that will happen if you let women in. But none of this is actually conveyed on the surface.”

So looking for and finding women in these ancient texts requires burrowing in as deeply as possible, she said, starting with a very close attention to grammar, literary devices and rhetorical devices, alongside trying to uncover the religious system and whatever we can uncover about history.

Jamison was trained as a historical and Indo-European linguist, and earned her doctorate from Yale in 1977. She’s been teaching at UCLA since 2002. She regularly teaches courses in Sanskrit, Middle Indo-Aryan, and old Iranian language and literature, Indo-European and Indo-Iranian linguistics, and undergraduate courses on classical Indian civilization.

Jamison said she also enjoys teaching in a freshman cluster course called “Neverending Stories: Multidisciplinary Perspectives on Myth.”

The Faculty Research Lecture — a UCLA tradition since 1925 — is free and open to the public and will be held on April 3 at 3 p.m. in the Schoenberg Music Building.