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A photo of Dr. Steven Jonas, Jason Belling and Paul Weiss of UCLA .

A step toward a more efficient way to make gene therapies to attack cancer, genetic disorders

A photo of Dr. Steven Jonas, Jason Belling and Paul Weiss of UCLA .

(From left) Dr. Steven Jonas, Jason Belling and Paul Weiss of UCLA (Photo Credit: Reed Hutchinson)

A UCLA-led research team today reports that it has developed a new method for delivering DNA into stem cells and immune cells safely, rapidly and economically. The method, described in the journal Proceedings of the National Academy of Sciences, could give scientists a new tool for manufacturing gene therapies for people with cancer, genetic disorders and blood diseases.

The study’s co-senior author is Paul Weiss, a UCLA distinguished professor of chemistry and biochemistry, of bioengineering and of materials science and engineering. “We are figuring out how to get gene-editing tools into cells efficiently, safely and economically,” he said. “We want to get them into enormous numbers of cells without using viruses, electroshock treatments or chemicals that will rip open the membrane and kill many of the cells, and our results so far are promising.”

In current practice, cells used for genetic therapies are sent to specialized labs, which can take up to two months to produce an individualized treatment. And those treatments are expensive: A single regimen for one patient can cost hundreds of thousands of dollars.

“We hope our method could be used in the future to prepare treatments that can be performed at the patient’s bedside,” Weiss said.

The method could be used with CRISPR, the genetic engineering technique that enables DNA to be edited with remarkable precision. However, using CRISPR efficiently, safely and economically in medical therapies has proven to be a challenge — one this new method may be able to solve.

The technique uses high-frequency acoustic waves coupled with millions of cells that flow through an “acoustofluidic device” in a cell culture liquid. The device was invented by the research team as part of the study; inside of it are tiny speakers that convert electrical signals to mechanical vibrations that are used to manipulate the cells.

That procedure opens up pores along the cells’ membranes that allow DNA and other biological cargo to enter the cells, and it enables the researchers to insert the cargo without the risk of damaging the cells by contacting them directly.

Dr. Steven Jonas, the study’s co-senior author and a UCLA clinical instructor in pediatrics, likened the soundwaves’ ability to move cells to the experience when audience members actually feel the sound at a concert.

“At a concert hall, you can feel the bass — and if you can feel the sound, the cell can feel the acoustic wave,” said Jonas, a member of the California NanoSystems Institute at UCLA, the UCLA Jonsson Comprehensive Cancer Center and Eli and Edythe Broad Center of Regenerative Medicine and Stem Cell Research at UCLA. “We can engineer the acoustic waves to direct the cells as needed.”

The researchers delivered short strands of DNA called plasmids into human blood cells and blood-forming stem cells that were intended specifically for laboratory research, and pumped millions of such cells through the acoustofluidic device. Once inside a cell, a plasmid can be made into a protein that may be missing or damaged, or it can give the cell new capabilities.

“When combined with new gene-editing approaches, the method enables us to correct a DNA sequence that is miscoded in a disease,” said Weiss, who also is a member of CNSI.

Plasmids used as templates for gene editing can make the correction because they have the right coded sequence for the desired protein, he explained.

Lead author Jason Belling, a UCLA graduate student in chemistry and biochemistry, was able to insert plasmids into the model cells used for testing about 60% of the time, without using any chemical and physical treatments.

“The viability is very high compared with other techniques,” Weiss said, “but we still want higher efficiencies and are working toward that.”

Jonas — whose expertise is in treating childhood cancer and blood disorders — said the research has the potential to benefit adults and children with cancer, immune system disorders and genetic diseases.

“If the delivery works, and it seems to, this research is an important step toward bringing new therapies more broadly to the patients who need them,” Jonas said. “Traditionally, we have treated cancers with chemotherapy, surgery, radiation and bone marrow transplantations. Now, we’re at an amazing era of medicine, where we can use different types of gene therapies that can train the immune system to fight cancer.”

A photo of a prototype of the acoustofluidic device developed by UCLA researchers.

A prototype of the acoustofluidic device developed by UCLA researchers. (Photo Credit: Reed Hutchinson)

Jonas said some existing treatments can take a patient’s T cells and adapt them with a gene that encodes for a receptor that allows it to target the cancer.

“We want to be the delivery service that gets these therapeutic packages to the cells,” he said. “I want to treat my patients with cells that are engineered in this way.”

For the technique to lead to viable treatments for disease, it would need to allow doctors  to process at least a couple hundred million cells — and in some cases, billions of cells — safely, rapidly and cost-effectively for each patient.

The new approach is still the subject of research and is not available to treat human patients.

The study’s other co-authors include Duke University professor Tony Huang, a pioneer of acoustofluidics and a UCLA alumnus; Dr. Stephen Young, distinguished professor of medicine and human genetics at the David Geffen School of Medicine at UCLA; and Dr. Satiro De Oliveira, a UCLA assistant professor of pediatrics.

The study was funded in part through a National Institutes of Health Director’s Early Independence Award for Jonas; the University of California Center for Accelerated Innovation; and Belling’s predoctoral fellowship through the National Heart, Lung, and Blood Institute. Jonas also has received young investigator awards from the Alex’s Lemonade Stand Foundation for Childhood Cancer Research, Hyundai Hope on Wheels Foundation for Pediatric Cancer Research, and the Tower Cancer Research Foundation. UCLA’s Technology Development Group Innovation Fund also provided funding.

Weiss’ research group has applied for patents on the acoustofluidic device and related devices, working with the Technology Development Group.

This article originally appeared in the UCLA Newsroom.

A photo of Lynn Vavreck and Miguel García-Garibay.

Two elected to American Academy of Arts and Sciences

A photo of Lynn Vavreck and Miguel García-Garibay.

From left: Lynn Vavreck, Miguel García-Garibay

Six exceptional UCLA professors and leaders — including the UCLA College’s Physical Sciences Dean Miguel García-Garibay and Political Science Professor Lynn Vavreck — were elected April 23 to the American Academy of Arts and Sciences, one of the nation’s most prestigious honorary societies. The other honorees include School of Law Dean Jennifer Mnookin, Education Professor Pedro Noguera, environmental champion Mary Nichols and Hammer Museum Director Ann Philbin.

“I am delighted to congratulate each of this year’s UCLA inductees, who are all deserving of this wonderful honor,” UCLA Chancellor Gene Block said. “Election to the American Academy of Arts and Sciences is a testament to the exceptional work of our scholars and leaders. The entire campus community can take pride in this news and their many accomplishments.”

A total of 276 artists, scholars, scientists and leaders in the public, nonprofit and private sectors who were elected to the Academy today. More about UCLA’s honorees:

Miguel García-Garibay, dean of the UCLA Division of Physical Sciences and professor of chemistry and biochemistry, has earned worldwide recognition in the fields of artificial molecular machines, organic photochemistry, solid-state organic chemistry and physical organic chemistry. He studies the interaction of light and molecules in crystals. Light can have enough energy to break and make bonds in molecules, and García-Garibay’s research team has shown that crystals offer an opportunity to control the outcome of these chemical reactions.

His research has applications for green chemistry — the design of chemical products and processes that reduce or eliminate the generation of hazardous substances — and it could lead to the production of specialty chemicals that would be very difficult to produce using traditional methods. Among his many honors, he was elected a fellow of the American Chemical Society in 2019.

Lynn Vavreck is UCLA’s Marvin Hoffenberg Professor of American Politics and Public Policy, a contributing columnist to the Upshot at the New York Times, and a recipient of many awards and honors, including the Andrew F. Carnegie Prize in the Humanities and Social Sciences. She is the author of five books, including “Identity Crisis: The 2016 Presidential Campaign and the Battle for the Meaning of America” and “The Gamble: Choice and Chance in the 2012 Presidential Election,” which has been described as the “definitive account” of that election.

Consultants in both political parties refer to her work on political messaging in “The Message Matters” as required reading for presidential candidates. “Identity Crisis” was awarded the 2019 Richard E. Neustadt Prize for the Best Book on Executive Politics by the Presidents and Executive Politics Section of the American Political Science Association.

Vavreck’s 2020 election project, Nationscape, is the largest study of presidential elections ever conducted in the United States. Interviewing more than 6,000 people a week, Nationscape will complete 500,000 interviews before next January’s inauguration.

► Read more about the Nationscape election project.

“The members of the class of 2020 have excelled in laboratories and lecture halls, they have amazed on concert stages and in surgical suites, and they have led in board rooms and courtrooms,” said David Oxtoby, president of the Academy. “With [the] election announcement, these new members are united by a place in history and by an opportunity to shape the future through the Academy’s work to advance the public good.”

The American Academy of Arts and Sciences was founded in 1780 by John Adams, John Hancock and others who believed the new republic should honor exceptionally accomplished individuals. Previous fellows have included George Washington, Benjamin Franklin, Alexander Hamilton, Ralph Waldo Emerson, Albert Einstein, Charles Darwin, Winston Churchill, Martin Luther King Jr. and Nelson Mandela.

It also is an independent policy research center that undertakes studies of complex and emerging problems. Current academy members represent today’s innovative thinkers in many fields and professions, including more than 250 Nobel and Pulitzer Prize winners.

This article originally appeared in the UCLA Newsroom.

An image of dust over the Sahara Desert.

Earth’s atmosphere far dustier than previously believed

An image of dust over the Sahara Desert.

Dust over the Sahara Desert (Photo Credit: NASA GSFC)

Dust is a key component of Earth’s climate system. When it interacts with clouds, oceans and the sun’s radiation, it has an overall impact on our planet’s living systems, affecting everything from weather and rainfall to global warming.

There are two types of dust in the atmosphere, both kicked up by high-velocity winds in dry areas. Fine dust tends to cool because it scatters sunlight, much like clouds do. Coarse dust, which is larger in size and originates in places like the Sahara Desert, tends to warm the atmosphere, much like greenhouse gases.

Knowing precisely how much coarse dust is in the atmosphere is essential for understanding not only the atmospheric phenomena that dust influences but also the degree to which dust may be warming the planet.

Now, UCLA scientists report that there is four times the amount of coarse dust in Earth’s atmosphere than is currently simulated by climate models. Their findings appear in the journal Science Advances.

The researchers found that Earth’s atmosphere contains 17 million metric tons of coarse dust — equivalent to 17 million elephants or the mass of every person in America put together.

“To properly represent the impact of dust as a whole on the Earth system, climate models must include an accurate treatment of coarse dust in the atmosphere,” said the study’s first author, Adeyemi Adebiyi, a postdoctoral researcher in UCLA’s Department of Atmospheric and Oceanic Sciences and a recipient of the University of California President’s Postdoctoral Fellowship.

By plugging this amount of missing coarse dust into models, Adebiyi said, it increases the likelihood that the net amount of dust overall — both fine and coarse — is warming rather than cooling the Earth’s climate system, from air to oceans.

Coarse dust particles warm the Earth’s entire climate system by absorbing both incoming radiation from the sun and outgoing radiation from the Earth’s surface. These particles can impact stability and circulation within our atmosphere, which may affect atmospheric phenomena like hurricanes.

Adebiyi worked with Jasper Kok, a UCLA associate professor of atmospheric and oceanic sciences, to determine the actual amount of coarse dust in the atmosphere by analyzing dozens of published aircraft-based observations, including recent measurements taken over the Sahara Desert, and comparing those with half a dozen widely used global atmospheric model simulations.

“When we compared our results with what is predicted by current climate models, we found a drastic difference,” Kok said. “State-of-the-art climate models account for only 4 million metric tons, but our results showed more than four times that amount.”

In addition, Adebiyi and Kok found that coarse dust leaves the atmosphere less quickly than current climate models predict. Air has a tendency to mix more turbulently when dust is present. In the case of the Sahara, air and dust mix in ways that push the dust upward, which can work against gravity and keep the dust in the air much longer, they said.

The scientists’ findings also show that because dust particles stay in the atmosphere longer, they are ultimately deposited further from their source than has been predicted by these models or explained by current theory. Dust particles blown from the Sahara, for example, can travel thousands of miles in the atmosphere, reaching as far as the Caribbean and the United States.

When desert dust ends up in oceans, it may stimulate the productivity of ocean ecosystems and increase the amount of carbon dioxide absorbed by the oceans.

Due to the way coarse dust interacts with the sun’s energy and clouds, it can also have a major impact on the timing of precipitation, as well as how much, or how little, rain falls.

“Models have been an invaluable tool for scientists,” said Adebiyi, “but when they miss most of the coarse dust in the atmosphere, it underestimates the impact that this type of dust has on critical aspects of life on Earth, from precipitation to cloud cover to ocean ecosystems to global temperature.”

This article originally appeared in the UCLA Newsroom.

A photo of Matie Zubiaurre, professor of Spanish and Portuguese in the UCLA College.

Spanish professor wins award for book on the cultural uses of garbage

A photo of Matie Zubiaurre, professor of Spanish and Portuguese in the UCLA College.

Matie Zubiaurre, professor of Spanish and Portuguese in the UCLA College. (Photo Courtesy of Matie Zubiaurre)

Maite Zubiaurre, professor of Spanish and Portuguese in the UCLA College, has been awarded the 2020 Norman L. and Roselea J. Goldberg Prize from Vanderbilt University Press for her book “Talking Trash. Cultural Uses of Waste.” The award recognizes the best book in the area of art and medicine.

In “Talking Trash,” Zubiaurre looks at refuse in its early stages, when it is still litter that can be found on city streets. She also focuses on a significant non-urban scene: the desert landscape and the clothing and other items that immigrants discard as they make their journey across the border.

Zubiaurre’s other books include “El espacio en la novela realista. Paisajes, miniaturas, perspectivas,” a book-length study of the dialectics of space and gender in European and Latin American realist fiction, and of “Cultures of the Erotic. Spain 1898-1939”, the first scholarly monograph that analyzes the diverse visual and textual representations of the erotic in Spanish popular culture during the so-called Silver Age between 1898 and 1936.

Some of Zubiaurre’s areas of expertise include comparative literature, gender studies, urban studies, cultural studies, European and Latin American Realism and Latina and Chicana fiction. She is also the author of numerous articles and critical editions and co-editor of an anthology of Spanish feminist thought, “Antología del pensamiento feminista español: 1726-2008.”

This article originally appeared in the UCLA Newsroom.

A photo of Stephanie Correa and Edward van Veen in Correa's UCLA laboratory

Research provides new insights into menopause and weight gain

A photo of Stephanie Correa and Edward van Veen in Correa's UCLA laboratory

Stephanie Correa and Edward van Veen in Correa’s UCLA laboratory (Photo Credit: Reed Hutchinson)

Can women in menopause get the benefits of hormone replacement therapy without the risks? A new UCLA study conducted with mice points in that direction, but additional research is necessary.

Women commonly experience hot flashes and weight gain, among other changes, during and after menopause. Hormone therapy, which gives women additional estrogen, can help alleviate some of these symptoms, but it has been linked to a higher risk of heart disease and breast cancer.

UCLA life scientists now report that a gene called reprimo, which is expressed by certain neurons in the brain, may play a role in menopause-related weight gain, a phenomenon not linked to increased eating. Their findings are published today in the journal Nature Metabolism.

“We want to figure out which neurons are mediating the beneficial portions of hormone therapy and mimic them without hormones,” said senior author Stephanie Correa, a UCLA assistant professor of integrative biology and physiology and a member of UCLA’s Brain Research Institute. “Hormone therapy can be beneficial, but it treats the entire brain and body with hormones. We may be able to bypass the hormone. That’s our goal, and it’s a big one. We haven’t achieved it yet, but we’re learning.”

Correa and her research team show that the reprimo gene is important for regulating temperature. Changes in temperature are known to affect body weight and may contribute to the weight gain often seen in menopause.

“It’s possible that reprimo is involved in the weight gain that accompanies menopause,” said co-lead author Edward van Veen, a project scientist in Correa’s laboratory. “If equivalent neurons exist in humans and we can find some way to tweak them, it might relieve much of the weight gain without the side effects of hormone therapy.”

A brain region called the hypothalamus is essential for survival in many species, from mice to humans; it controls eating, drinking, reproduction and body-temperature regulation, among other vital functions. Correa and her research team studied dozens of genes in the hypothalami of more than 50 mice, both female and male, starting at about eight weeks of age, shortly after they reach reproductive age.

The team used a technique known as single-cell RNA-seq, which allows biologists to study individual cells one at a time, to investigate which neurons in an area of the hypothalamus known as the ventromedial hypothalamus might mediate these different functions.

“We had hints there were different types of neurons in the ventromedial hypothalamus, and this region is very different in males and females, so we studied hundreds of cells in males and females to identify the different types of neurons and determine whether there are sex differences,” Correa said.

The biologists were most interested in neurons that have estrogen receptors. These receptors bind to the hormone and are subsequently able regulate to the activity of specific genes in the neuron, a process known as gene expression. The team’s most significant findings centered on the reprimo gene, which is expressed in one group, or population, of these estrogen-responsive neurons, restricted almost entirely to females.

“We were excited to find not only populations of estrogen-responsive neurons but also differences in these populations between males and females,” said co-lead author Laura Kammel, a former UCLA doctoral student in Correa’s laboratory.

“The difference between females and males in reprimo in the ventromedial hypothalamus is like night and day,” Correa said. “The females express a ton of it, and males express little, if any, reprimo in this brain region. Of the dozens of genes I have studied in this region, this is easily the strongest sex difference I have ever seen.”

In a series of experiments, the biologists interfered with the function of reprimo in the ventromedial hypothalamus in about two dozen mice. In one experiment, they shut off reprimo in female mice by using an RNA molecular compound that interferes with how the gene works in neurons. In another, they increased reprimo expression in male mice by removing an estrogen receptor from the neurons. In both cases, body temperature changed substantially, demonstrating a link between reprimo’s role in temperature and the effects of estrogen.

“We know that reprimo is important in regulating body temperature, but we don’t know what it is actually doing in neurons,” van Veen said. “We want to find out.”

Correa and her team also report that estrogen acts on another gene, Tac1, that is significantly increased in the ventromedial hypothalamus of female mice, although the difference is not nearly as dramatic as with reprimo. Tac1 has been shown to promote physical activity in female mice.

Estrogen receptor alpha, one of three estrogen receptors, is found in neurons in the same region of the ventromedial hypothalamus as Tac1 and reprimo. When the researchers removed that estrogen receptor, they found it led to obesity and reduced movement in female mice.

The results, the researchers said, not only aid in their understanding of the interplay between genes and estrogen but may also have implications for understanding obesity.

Summarizing the research, van Veen said: “The ventromedial hypothalamus is involved in movement and temperature regulation. We know estrogen affects movement and temperature. From Stephanie Correa’s previous research, we learned the estrogen response of neurons that affect movement, and now we think we know the estrogen response of neurons that affect temperature. It’s interesting that they are in the same location but distinct.”

“Our findings suggest reprimo is controlling some of the effects of estrogen on temperature,” Correa said. “If it is controlling the beneficial effects, then maybe we can manipulate it — with a drug that targets reprimo or the neurons that express reprimo — as an alternative to hormone therapy and get around the requirement for estrogen. We are studying the brain in a nuanced way and trying to learn which cells or which genes are important to target for potential therapies.”

Co-authors are co-lead author Laura Kammel, a former UCLA doctoral student in Correa’s laboratory; Xia Yang, a UCLA associate professor of integrative biology and physiology; Arthur Arnold, a UCLA distinguished professor of integrative biology and physiology; and Marc Liesa-Roig, a UCLA assistant professor-in-residence at the David Geffen School of Medicine at UCLA.

This article originally appeared in the UCLA Newsroom.

A photo of the sidewalk with chalk that says "Play your part, stay apart"

Play your part, stay apart: Advice and insight on physical distancing

A photo of the sidewalk with chalk that says "Play your part, stay apart"

Play your part, stay apart (Photo Credit: Jessica Wolf)

It has been a month since the wide-ranging safer-at-home directive went into effect in Los Angeles on March 17, following, and followed by, similar policies in other states and countries around the world.

It’s been hard. It’s wreaked havoc on our economy, our communities and our sense of emotional well-being. People understandably want to connect, go outside, share physical spaces, make a living, enjoy friends and family.

We asked Daniel Fessler, professor of anthropology and director of the UCLA Bedari Kindness Institute to help unpack why physical distancing feels so counterintuitive even while it represents one of the greatest mass acts of kindness — what scientists call “prosocial” behavior — we have witnessed as a species.

Why is it so hard to stay away from the people we are closest to socially? 

Our evolved mental mechanisms prioritize close social relationships over disease avoidance because those relationships were so important to the survival of our ancestors. One of the results of this is that we underestimate the risk of contagion that is posed by those to whom we are emotionally close. And as a consequence, people visit their relatives and close friends, and by so doing, they put at risk those whom they love the most.

The truth is, you’re probably even more dangerous to your loved ones than you are to strangers. After all, when’s the last time that you hugged a stranger on the street? If you care about the welfare of people you care about, then stay away from them.

Why is it so hard for us to fully accept that we might be dangerous to others, even if we don’t feel sick?  

Our evolved mental mechanisms are only attuned to overt cues of illness, so it’s difficult for us to grasp that we can be symptom-free and still infectious.

We can sort of understand that in an abstract way, but it’s hard for us to understand it in an emotional way. Likewise, our evolved mechanisms are attuned to harm that is tangible and immediate. The harm that we can do others is transmitted invisibly in this current situation and occurs after a delay of days or weeks. I’m quite confident that none of those college students who were partying on the beach in Florida during spring break would ever intentionally run over an elderly person in a crosswalk, but they’re potentially doing exactly that by contracting and spreading the virus.

How do we remind ourselves that staying away from one another physically is actually a huge act of kindness right now? 

As individuals, we all have a role to play in mitigating the impact of this disease. But problematically, social distancing doesn’t feel like prosocial behavior. And the reason it doesn’t feel like prosocial behavior is because in the world of our ancestors, helping other people and working together meant working face-to-face and side-by-side. You can think, for example, about how good it feels to help a stranger on the street or to work as a team to clean up trash on a beach or repaint an elementary school.

These things feel really good, right? And this is because our evolved psychological mechanisms are sensitive to cues that we are part of a prosocial cooperative group.

You may also think about how great it feels to do the wave with a huge crowd at a sporting event or to sing the national anthem together with thousands of people. These things are emotionally moving. They feel great because we are sensitive to the situation in which we’re coordinating our actions with those of many people around us towards a common goal.

Yet in the current crisis, for most of us, the first prosocial action that we must engage in is to stay away from other people. And ordinarily, staying away from other people can feel selfish. So staying away from other people doesn’t feel like we’re helping anyone.

I encourage everyone to think creatively. How can you help? For example, millions of kids are out of school right now. Can you tutor children via video link? Maybe just read a child a story. Many small businesses are in danger of going bankrupt. Can you purchase products or services at a distance that will help them to stay afloat?

Or maybe you can help deliver meals or medication to the elderly or to children who normally rely on school lunches and school nurses for their needs — of course, conducting yourself appropriately with regard to the safeguards of hygiene and social distancing when you are making those deliveries. Think outside the box. Get some ideas online. Find a way to help other people while still playing your part and staying apart.

What can we do to encourage others to continue to practice safe distancing until city and state leaders relax guidelines?

If you see someone ignoring social distancing guidelines, you need to acknowledge in discussion with them that you understand that it may seem safe because neither you nor they feel sick right now. But despite this, it doesn’t mean that either of you can’t transmit the virus to the other or to someone else. How we feel physically is simply not an accurate index of whether we might harm other people by being near them. Those kinds of conversations, of course, you need to hold at a safe distance, six feet or so.

In having those conversations, it’s helpful to think about language. Language can reflect the priorities and needs at the moment. People coin new words all the time. Just think, for example: Phrases like “gig economy,” “screen time” or “trending” weren’t things a few years back. I find acronyms particularly useful in this regard. You can Google the origins of two of my favorites — snafu (situation normal, all fouled up) and fubar (fouled up beyond all recognition) — two terms that were coined during other desperate emergency times.

We can coin a new acronym, a new word: PYPSA. It stands for “Play Your Part, Stay Apart.” You can use the word as praise for people who are doing a great job of social distancing: “Hey, man, way to go! You’re really PYPSA-ing,” and remind people who might forget or who might underestimate the importance of social distancing.

This article originally appeared in the UCLA Newsroom.

A photo of James Lloyd-Smith.

Study reveals how long COVID-19 remains infectious on cardboard, metal and plastic

The virus that causes COVID-19 remains for several hours to days on surfaces and in aerosols, a new study published in the New England Journal of Medicine found.

The study suggests that people may acquire the coronavirus through the air and after touching contaminated objects. Scientists discovered the virus is detectable for up to three hours in aerosols, up to four hours on copper, up to 24 hours on cardboard and up to two to three days on plastic and stainless steel.

A photo of James Lloyd-Smith in his office.

James Lloyd-Smith

“This virus is quite transmissible through relatively casual contact, making this pathogen very hard to contain,” said James Lloyd-Smith, a co-author of the study and a UCLA professor of ecology and evolutionary biology. “If you’re touching items that someone else has recently handled, be aware they could be contaminated and wash your hands.”

The study attempted to mimic the virus being deposited onto everyday surfaces in a household or hospital setting by an infected person through coughing or touching objects, for example. The scientists then investigated how long the virus remained infectious on these surfaces.

The study’s authors are from UCLA, the National Institutes of Health’s National Institute of Allergy and Infectious Diseases, the Centers for Disease Control and Prevention, and Princeton University. They include Amandine Gamble, a UCLA postdoctoral researcher in Lloyd-Smith’s laboratory.

In February, Lloyd-Smith and colleagues reported in the journal eLife that screening travelers for COVID-19 is not very effective. People infected with the virus — officially named SARS-CoV-2 — may be spreading the virus without knowing they have it or before symptoms appear. Lloyd-Smith said the biology and epidemiology of the virus make infection extremely difficult to detect in its early stages because the majority of cases show no symptoms for five days or longer after exposure.

“Many people won’t have developed symptoms yet,” Lloyd-Smith said. “Based on our earlier analysis of flu pandemic data, many people may not choose to disclose if they do know.”

The new study supports guidance from public health professionals to slow the spread of COVID-19:

  • Avoid close contact with people who are sick.
  • Avoid touching your eyes, nose and mouth.
  • Stay home when you are sick.
  • Cover coughs or sneezes with a tissue, and dispose of the tissue in the trash.
  • Clean and disinfect frequently touched objects and surfaces using a household cleaning spray or wipe.

This article originally appeared in the UCLA Newsroom.

Picture of a valley oak tree.

One of California’s iconic tree species offers lessons for conservation

Picture of a valley oak tree.

The valley oak, the largest oak in California, grows to over 100 feet tall and provides habitat and food for a variety of animals. Photo credit: Victoria Sork/UCLA

 

With increasing regularity, Californians are witnessing firsthand the destructive power of wildfires. But not everyone sees what happens after the flames die down, when debris is cleared, homes and lives rebuilt — and trees replanted to help nature recover.

New research led by UCLA evolutionary biologist Victoria Sork examines whether the trees being replanted in the wake of California’s fires will be able to survive a climate that is continuing to warm.

The study, which is published in the Proceedings of the Natural Academy of Sciences, focuses on California’s iconic valley oak. The research is among the first to demonstrate the potential of using genomics to inform conservation strategies — essentially giving species an evolutionary boost. The study showed that planting trees that are genetically better suited to higher temperatures makes them more likely to survive and grow to maturity.

“When we think about managing ecosystems under rapidly changing climates, we have to realize trees need to be able to survive past 50 years,” Sork said.

The paper also discovered something surprising: The valley oak, an essential component of many ecosystems in California, is already poorly adapted to its environment — even considering climate conditions in 2019.

“They actually seem to grow better in cooler climates than they’re in right now,” said Luke Browne, a postdoctoral scholar at the UCLA La Kretz Center for California Conservation Science and the study’s lead author. “They might grow better if climates were more like they were 21,000 years ago, during the last ice age.”

During the peak of the last ice age, summer temperatures were about 4 to 5 degrees Celsius colder, and ice covered most of Canada and mountainous areas of the U.S.

In the fields of conservation and land management, it is a common assumption that plants and animals are adapted to their environments — that’s how evolution and natural selection are supposed to work. The new research casts doubt on that assumption.

The study is part of an ongoing project initiated by Sork and Jessica Wright, an expert in conservation genetics at the USDA Forest Service, more than 10 years ago.

Researchers gathered 11,000 seeds from 94 locations throughout the trees’ range, which stretches from the Santa Monica Mountains to the Cascade foothills in the northern part of the state. They grew them to saplings in a greenhouse and planted them in two large experimental gardens, in Chico and Placerville, California. They tracked how well trees from different locations grew, and sequenced the genomes of their mother trees to link genetic information and growth rates.

The researchers then identified which genetic variants would be more likely to thrive as climate change continues to warm California. They predicted that, under predicted future warmer temperatures, trees containing beneficial genetic variations would have 11% higher growth rates than the average for all of the trees in the experiment, and 25% higher growth rates than the trees without the beneficial variations.

Information like that could help the U.S. Forest Service, for example, in its efforts to restore forests with species that have the best chance for long-term survival.

“Studies like this one provide valuable insights that help land managers make informed decisions on reforestation projects,” Wright said. “When planting trees in a particular location, managers have to decide where to collect the acorns.”

By 2070, average temperatures in the state are projected to be up to 4.8 degrees warmer than they were during the mid- to late 20th century.

“That’s going to have consequences for how fast these trees grow,” Browne said. “We’re at a challenging time to figure out the best way to do conservation science. This paper shows one approach we could use that takes advantage of modern genomics.”

The study did not determine why valley oaks are not well adapted to their environment. It might be because the climate has already warmed up so much, the trees’ long lifespans — up to 500 years — or some other, unknown factor.

The valley oak is the largest oak in California; it grows to over 100 feet tall, and has dark green leaves and a deeply grooved trunk. It is considered a foundational species because it provides habitat and food for a variety of animals, including squirrels, birds, deer and insects. In parts of the state, it is one of the only species of tree that exists. Valley oaks provide benefits to humans, too: filtering water and providing shady places to escape the heat.

Although it focuses on the oak, the paper has broader implications for conservation science in a changing climate — especially for species that evolve and adapt slowly. That’s what Sork and Wright were thinking when they initiated the project.

At the time, they hoped to find conservation strategies that could eventually be implemented using genetic information alone — without extensive field experiments.

“Not everyone in the world is going to be able to collect 11,000 seeds and plant them in a common garden,” Sork said.

This article originally appeared in the UCLA Newsroom.

UCLA astronomer gets best look at first comet from outside our solar system

The comet 2I/Borisov, as seen on Oct. 12 with NASA’s Hubble Space Telescope. Scientists believe the comet is from another solar system. Photo credit: NASA, ESA and David Jewitt/UCLA

David Jewitt, a UCLA professor of planetary science and astronomy, has captured the best and sharpest look at a comet from outside of our solar system that recently barged into our own. It is the first interstellar comet astronomers have observed.

Comet 2I/Borisov (the “I” stands for interstellar) is following a path around the sun at a blazing speed of approximately 110,000 miles per hour, or about as fast as Earth travels around the sun. Jewitt studied it on Oct. 12 using NASA’s Hubble Space Telescope, which captured images of the object when it was about 260 million miles away. He observed a central concentration of dust around the comet’s solid icy nucleus — the nucleus itself is too small to be seen by Hubble — with a 100,000-mile-long dust tail streaming behind.

Jewitt said it’s very different from another interstellar object, dubbed ‘Oumuamua, that a University of Hawaii astronomer observed in 2017 before it raced out of our solar system.

“‘Oumuamua looked like a bare rock, but Borisov is really active — more like a normal comet,” said Jewitt, who leads the Hubble team. “It’s a puzzle why these two are so different. There is so much dust on this thing we’ll have to work hard to dig out the nucleus.”

That work will involve sophisticated image processing to separate the light scattered from the nucleus from light scattered by dust.

► View a 2-second time lapse video of the comet

2I/Borisov and ‘Oumuamua are the first two objects that have traveled from outside of our solar system into ours that astronomers have observed, but that’s because scientists’ knowledge and equipment are much better now than they ever have been, and because they know how to find them. One study indicates there are thousands of such comets in our solar system at any given time, although most are too faint to be detected with current telescopes.

Until 2I/Borisov, every comet that astronomers have observed originated from one of two places. One is the Kuiper belt, a region at the periphery of our solar system, beyond Neptune, that Jewitt co-discovered in 1992. The other is the Oort Cloud, a very large spherical region approximately a light-year from the sun, which astronomers think contains hundreds of billions of comets.

2I/Borisov was initially detected on Aug. 30 by Gennady Borisov at the Crimean Astrophysical Observatory, when it was 300 million miles from the sun. Jewitt said its unusually fast speed — too fast for the sun’s gravity to keep it bound in an orbit — indicates that it came from another solar system and that it is on a long path en route back to its home solar system.

Because the comet was presumably forged in a distant solar system, the comet provides valuable clues about the chemical composition and structure of the system where it originated.

2I/Borisov will be visible in the southern sky for several months. It will make its closest approach to the sun on Dec. 7, when it will be twice as far from the sun as Earth is. By the middle of 2020, it will pass Jupiter on its way back into interstellar space, where it will drift for billions of years, Jewitt said.

Comets are icy bodies thought to be fragments left behind when planets form in the outer parts of planetary systems.

20 new moons for Saturn

In separate research that has not yet been published, Jewitt is part of a team that has identified 20 previously undiscovered moons of Saturn, for a new total of 82 moons. The revised figure gives Saturn more moons than Jupiter, which has 79.

The new objects are all small, typically a few miles in diameter, and were discovered using the Subaru telescope on Maunakea in Hawaii. They can be seen only using the world’s largest telescopes, Jewitt said.

The moons might have formed in the Kuiper belt, said Jewitt, a member of the National Academy of Sciences and a fellow of the American Association for the Advancement of Science and of the American Academy of Arts and Sciences.

The research team was headed by Scott Sheppard, a staff scientist at the Carnegie Institution for Science, and includes Jan Kleyna, a postdoctoral scholar at the University of Hawaii.

This article originally appeared in the UCLA Newsroom.

Photo of artist rendering of SO-2 star.

Einstein’s general relativity theory is questioned but still stands ‘for now,’ team reports

Photo of artist rendering of SO-2 star.

A star known as S0-2 (the blue and green object in this artist’s rendering) made its closest approach to the supermassive black hole at the center of the Milky Way in 2018. Artist’s rendering by Nicolle Fuller/National Science Foundation.

More than 100 years after Albert Einstein published his iconic theory of general relativity, it is beginning to fray at the edges, said Andrea Ghez, UCLA professor of physics and astronomy. Now, in the most comprehensive test of general relativity near the monstrous black hole at the center of our galaxy, Ghez and her research team report July 25 in the journal Science that Einstein’s theory of general relativity holds up.

“Einstein’s right, at least for now,” said Ghez, a co-lead author of the research. “We can absolutely rule out Newton’s law of gravity. Our observations are consistent with Einstein’s theory of general relativity. However, his theory is definitely showing vulnerability. It cannot fully explain gravity inside a black hole, and at some point we will need to move beyond Einstein’s theory to a more comprehensive theory of gravity that explains what a black hole is.”

Einstein’s 1915 theory of general relativity holds that what we perceive as the force of gravity arises from the curvature of space and time. The scientist proposed that objects such as the sun and the Earth change this geometry. Einstein’s theory is the best description of how gravity works, said Ghez, whose UCLA-led team of astronomers has made direct measurements of the phenomenon near a supermassive black hole — research Ghez describes as “extreme astrophysics.”

The laws of physics, including gravity, should be valid everywhere in the universe, said Ghez, who added that her research team is one of only two groups in the world to watch a star known as S0-2 make a complete orbit in three dimensions around the supermassive black hole at the center of the Milky Way. The full orbit takes 16 years, and the black hole’s mass is about 4 million times that of the sun.

The researchers say their work is the most detailed study ever conducted into the supermassive black hole and Einstein’s theory of general relativity.

The key data in the research were spectra that Ghez’s team analyzed last April, May and September as her “favorite star” made its closest approach to the enormous black hole. Spectra, which Ghez described as the “rainbow of light” from stars, show the intensity of light and offer important information about the star from which the light travels. Spectra also show the composition of the star. These data were combined with measurements Ghez and her team have made over the last 24 years.

Spectra — collected at the W.M. Keck Observatory in Hawaii using a spectrograph built at UCLA by a team led by colleague James Larkin — provide the third dimension, revealing the star’s motion at a level of precision not previously attained. (Images of the star the researchers took at the Keck Observatory provide the two other dimensions.) Larkin’s instrument takes light from a star and disperses it, similar to the way raindrops disperse light from the sun to create a rainbow, Ghez said.

“What’s so special about S0-2 is we have its complete orbit in three dimensions,” said Ghez, who holds the Lauren B. Leichtman and Arthur E. Levine Chair in Astrophysics. “That’s what gives us the entry ticket into the tests of general relativity. We asked how gravity behaves near a supermassive black hole and whether Einstein’s theory is telling us the full story. Seeing stars go through their complete orbit provides the first opportunity to test fundamental physics using the motions of these stars.”

Ghez’s research team was able to see the co-mingling of space and time near the supermassive black hole. “In Newton’s version of gravity, space and time are separate, and do not co-mingle; under Einstein, they get completely co-mingled near a black hole,” she said.

“Making a measurement of such fundamental importance has required years of patient observing, enabled by state-of-the-art technology,” said Richard Green, director of the National Science Foundation’s division of astronomical sciences. For more than two decades, the division has supported Ghez, along with several of the technical elements critical to the research team’s discovery. “Through their rigorous efforts, Ghez and her collaborators have produced a high-significance validation of Einstein’s idea about strong gravity.”

Keck Observatory Director Hilton Lewis called Ghez “one of our most passionate and tenacious Keck users.” “Her latest groundbreaking research,” he said, “is the culmination of unwavering commitment over the past two decades to unlock the mysteries of the supermassive black hole at the center of our Milky Way galaxy.”

The researchers studied photons — particles of light — as they traveled from S0-2 to Earth. S0-2 moves around the black hole at blistering speeds of more than 16 million miles per hour at its closest approach. Einstein had reported that in this region close to the black hole, photons have to do extra work. Their wavelength as they leave the star depends not only on how fast the star is moving, but also on how much energy the photons expend to escape the black hole’s powerful gravitational field. Near a black hole, gravity is much stronger than on Earth.

Ghez was given the opportunity to present partial data last summer, but chose not to so that her team could thoroughly analyze the data first. “We’re learning how gravity works. It’s one of four fundamental forces and the one we have tested the least,” she said. “There are many regions where we just haven’t asked, how does gravity work here? It’s easy to be overconfident and there are many ways to misinterpret the data, many ways that small errors can accumulate into significant mistakes, which is why we did not rush our analysis.”

Ghez, a 2008 recipient of the MacArthur “Genius” Fellowship, studies more than 3,000 stars that orbit the supermassive black hole. Hundreds of them are young, she said, in a region where astronomers did not expect to see them.

It takes 26,000 years for the photons from S0-2 to reach Earth. “We’re so excited, and have been preparing for years to make these measurements,” said Ghez, who directs the UCLA Galactic Center Group. “For us, it’s visceral, it’s now — but it actually happened 26,000 years ago!”

This is the first of many tests of general relativity Ghez’s research team will conduct on stars near the supermassive black hole. Among the stars that most interest her is S0-102, which has the shortest orbit, taking 11 1/2 years to complete a full orbit around the black hole. Most of the stars Ghez studies have orbits of much longer than a human lifespan.

Ghez’s team took measurements about every four nights during crucial periods in 2018 using the Keck Observatory — which sits atop Hawaii’s dormant Mauna Kea volcano and houses one of the world’s largest and premier optical and infrared telescopes. Measurements are also taken with an optical-infrared telescope at Gemini Observatory and Subaru Telescope, also in Hawaii. She and her team have used these telescopes both on site in Hawaii and remotely from an observation room in UCLA’s department of physics and astronomy.

Black holes have such high density that nothing can escape their gravitational pull, not even light. (They cannot be seen directly, but their influence on nearby stars is visible and provides a signature. Once something crosses the “event horizon” of a black hole, it will not be able to escape. However, the star S0-2 is still rather far from the event horizon, even at its closest approach, so its photons do not get pulled in.)

Photo of telescope pointing to the sky.

Lasers from the two Keck telescopes point in the direction of the center of our galaxy. Each laser creates an “artificial star” that astronomers can use to correct for the blurring caused by the Earth’s atmosphere. Photo: Ethan Tweedie

Ghez’s co-authors include Tuan Do, lead author of the Science paper, a UCLA research scientist and deputy director of the UCLA Galactic Center Group; Aurelien Hees, a former UCLA postdoctoral scholar, now a researcher at the Paris Observatory; Mark Morris, UCLA professor of physics and astronomy; Eric Becklin, UCLA professor emeritus of physics and astronomy; Smadar Naoz, UCLA assistant professor of physics and astronomy; Jessica Lu, a former UCLA graduate student who is now a UC Berkeley assistant professor of astronomy; UCLA graduate student Devin Chu; Greg Martinez, UCLA project scientist; Shoko Sakai, a UCLA research scientist; Shogo Nishiyama, associate professor with Japan’s Miyagi University of Education; and Rainer Schoedel, a researcher with Spain’s Instituto de Astrofısica de Andalucıa.

The National Science Foundation has funded Ghez’s research for the last 25 years. More recently, her research has also been supported by the W.M. Keck Foundation, the Gordon and Betty Moore Foundation and the Heising-Simons Foundation; as well as Lauren Leichtman and Arthur Levine, and Howard and Astrid Preston.

In 1998, Ghez answered one of astronomy’s most important questions, helping to show that a supermassive black hole resides at the center of our Milky Way galaxy. The question had been a subject of much debate among astronomers for more than a quarter of a century.

A powerful technology that Ghez helped to pioneer, called adaptive optics, corrects the distorting effects of the Earth’s atmosphere in real time. With adaptive optics at Keck Observatory, Ghez and her colleagues have revealed many surprises about the environments surrounding supermassive black holes. For example, they discovered young stars where none was expected to be seen and a lack of old stars where many were anticipated. It’s unclear whether S0-2 is young or just masquerading as a young star, Ghez said.

In 2000, she and colleagues reported that for the first time, astronomers had seen stars accelerate around the supermassive black hole. In 2003, Ghez reported that the case for the Milky Way’s black hole had been strengthened substantially and that all of the proposed alternatives could be excluded.

In 2005, Ghez and her colleagues took the first clear picture of the center of the Milky Way, including the area surrounding the black hole, at Keck Observatory. And in 2017, Ghez’s research team reported that S0-2 does not have a companion star, solving another mystery.

This article originally appeared in the UCLA Newsroom.