New study maps risk areas for citrus greening

Orange juice is a breakfast staple, but the future availability of citrus products is threatened by the global spread of citrus greening disease, which prevents commercially viable fruit from forming.

A new study by an international research team — including UF medical geographer SADIE RYAN — identifies global regions most at risk of, and most resilient to, citrus greening.

“Translating these models into maps helps communicate our findings to citrus stakeholders, and creates a baseline for thinking about potential climate change impacts,” Ryan said. She holds joint positions with UF’s Emerging Pathogens Institute and the Department of Geography.

The disease has devastated Florida’s citrus industry and led to a nearly 75 percent decline in boxed orange production in 2018 — the lowest production level since World War II, according to the Tampa Bay Times. Jobs in the state’s citrus industry have declined by 59 percent in the past decade, allowing Brazil to emerge as the top global producer of orange juice and costing Florida an estimated $2 billion in economic impact.

Citrus greening is caused by a bacterium transmitted by the Asian citrus psyllid insect. Both the pathogen and insect have spread in recent years, devastating regions famous for high citrus production.

Affected fruits end up smaller than normal, with a blotchy green appearance, malformed lobes and low-quality juice. As citrus greening menaces growers worldwide, the citrus industry’s future may depend on identifying locations most resilient to production collapse.

A new paper* published in the Journal of Applied Ecology that Ryan co-authored with a research team investigates the temperature-driven comfort zone for citrus greening transmission.

Led by Rachel Taylor of the United Kingdom’s Animal and Plant Health Agency, the research team modeled how citrus greening transmission depends on temperature, and then mapped how this translates into areas where the disease could become established.

The model found that the successful infection of host plants can occur between 60.8˚F and 91.4˚F (16˚C to 33˚C), with peak transmission at around 77˚F (25˚C). The authors then mapped global suitability to show which months have temperature conditions that would place citrus groves at risk for infection.

Global maps produced by Sadie Ryan’s lab illustrate the number of months throughout the year the citrus greening bacterium is more likely to be transmitted.

This work provides critical information for citrus production and crop management moving forward. In areas known for high citrus production, preventing the establishment of the disease through increased surveillance and management may help prevent the devastating effects that citrus greening has had on other growers.

This is an excerpt from a story originally published by the Emerging Pathogens Institute. To read the full story, click here.

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With a mathematical time machine, UF geologist reconstructs what happened in the Earth’s interior 55 million years ago

Geologist ALESSANDRO FORTE is not shy about the ambitious nature of his recent research.

“In some sense, what we’re doing is almost an act of hubris,” he said. “We’re taking the laws of physics and reversing them.”

By that, Forte means that he and his collaborators are tracing the movement of heat backwards to see what the Earth’s interior looked like tens of millions of years ago. Using thermodynamic equations and present-day seismological data, the researchers create high-resolution, three-dimensional maps of ancient conditions deep below the Earth’s surface. Forte compared the result to a CAT scan, with geological features in place of bodily organs.

In a new study* led by Petar Glišović of Université du Québec à Montréal, published in Proceedings of the National Academy of Sciences, Forte reconstructed the phenomena occurring under the North Atlantic Ocean 55 million years ago that may have led to a period of rapid global warming.

During this period, known as the Paleocene–Eocene Thermal Maximum (PETM), global temperatures are estimated to have increased by at least 5˚C, an escalation believed to be associated with a rise in greenhouse gases.

At the time, little permanent ice could exist on the Earth’s surface, and sea levels rose.

“The Earth went through essentially what I call a ‘fever,’” Forte said.

This era, though much hotter than today, interests many climate scientists as a possible warning of the conditions that could appear if humans continue to pump greenhouse gases into the atmosphere.

Yet questions have remained about what caused the release of gases during the PETM — questions Forte and his team hope their new study will help resolve.

Many geologists suspect that as the North Atlantic Ocean widened 55 million years ago, volcanic activity pumped lava into hydrocarbon-rich rock, causing a rapid release of carbon dioxide and methane: “A greenhouse gas ‘burp,’” Forte called it.

With their maps, Forte and his team believe they have reconstructed sources of this volcanic activity: Two deeply-seated upwellings of hot rock underneath the earth’s surface. These “plumes,” the reconstructions show, reached all the way down to the boundary of the Earth’s mantle and core.

Reconstruction of the Earth's Interior
A reconstruction of the 3-D structure of the Earth’s mantle below the North Atlantic 55 million years ago. (From Fig. 1 in Petar Glišović and Alessandro M. Forte’s paper.)

One of the plumes, then under Greenland and today under Iceland, has long been suspected to have played a role in the volcanic activity. But the importance of the second, found under the Azores — an archipelago about 850 miles west of Portugal — is a new discovery.

With the success of this work, Forte is eager to see what other parts of the Earth’s interior looked like 70 million years ago.

“We’ve taken on these difficult problems and produced these compelling images,” he said. “Now let’s start looking at what’s going on elsewhere.”

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New research helps us to better understand Zika

Zika may not dominate the news cycle like it did several years ago, but that doesn’t make it any less of a threat.

Biology chair and professor MARTA WAYNE, along with biology professor MICHAEL MIYAMOTO and collaborator Helen Piontkivska from Kent State University, authored a paper in BioEssays with a compelling hypothesis detailing how the Zika virus can lead to devastating consequences in the infected.

A virus primarily spread through the bite of an infected Aedes species mosquito, Zika can most prominently lead to a birth defect in the fetuses of pregnant women. This defect, known as microcephaly, causes the child to be born with a smaller head than expected and oftentimes developmental issues due to a smaller brain.

The research team explored how Zika induces neurological damage by essentially causing a person’s immune system to go haywire.

An infected member of the Aedes species of mosquito spreads the Zika virus. CDC, 2005, James Gathany

The team argues that the Zika virus infection leads to an immune response which includes dysregulation of the host’s ADAR enzymes (adenosine deaminases acting on RNA), altering the expression of key proteins for neuronal function in both infants and adults.

“ADAR is something that our bodies have to defend against viruses,” Wayne said. “But if it’s dysregulated, it also has other functions in the absence of virus, which includes things like making the correct edits to RNA in the brain. If those don’t get made, or too little or too much are made, you have problems.”

These problems could include the neurodevelopmental and neurodegenerative pathologies of Zika and the often associated Guillain-Barré syndrome, a rare disorder where the body’s immune system attacks the nerves. The syndrome has been found in higher numbers in countries that experienced Zika outbreaks.

This explanation points to possible new avenues of treatment for Zika and Guillain-Barré by turning off ADAR, and potentially for understanding a number of other neurological disorders like Parkinson’s disease — pending testing.

The team didn’t expect to head down these paths when they set out to investigate Zika, but the work has now opened new areas to explore.

“(This study) highlights the value of basic research — how it’s a journey and how you don’t know where this journey will take you,” Miyamoto said. “You just don’t know where you’re going to end up.”

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Uwem Akpan is one of the newest members of the Creative Writing Program

Portrait of Uwem AkpanAssistant Professor of English UWEM AKPAN exploded onto the American literary scene in 2005 when his short story “An Ex-Mas Feast” was first published in the debut-fiction issue of The New Yorker.

Set in the slums of Nairobi, the story is told from the viewpoint of a young boy who details the desperate living conditions of his family, focusing heavily on his sister — a pre-adolescent prostitute who works to pay off the family’s debt and provide school fees for her brother.

The piece kicks off his breakout 2008 short story collection, Say You’re One of Them, which consists of five stories, each set in a different African nation and told through the eyes of children, that reveal the worst of humanity — poverty, discrimination and genocide — while leaving the possibility for grace.

Akpan’s first collection of short stories, Say You’re One of Them.

Akpan joined UF in the fall of 2018 and is one of the newest members of the Creative Writing faculty. The son of teachers, he grew up in the village of Ikot Akpan Eda in southern Nigeria. As he told Oprah Winfrey, who selected Say You’re One of Them for her book club in 2009, he discovered he had the talent to write fiction when he was 29.

Winfrey praised the book, calling it “one of the most powerful collections of short stories I believe I have ever read.”

Akpan studied philosophy and humanities at Creighton and Gonzaga universities and finished his theology degree at the Catholic University of East Africa in Kenya. He then graduated from the MFA program at the University of Michigan in 2006. Akpan has held visiting writer positions at the Loyola University Chicago’s Center for Catholic Intellectual Heritage, the New York Public Library’s Cullman Center, the University of Michigan’s Humanities Institute and the University of Nevada’s Black Mountain Institute.

“I am happy to be here,” Akpan said when asked about his move to UF. “I thank everyone for the hospitality they’ve extended to me since I arrived. And, oh, I love the Spanish moss. It’s everywhere!”

Say You’re One of Them received an overwhelming response for a first book and was reviewed in The New York Times, The Washington Post and The Paris Review, among others. The collection also won the PEN Open Book Award and the Commonwealth Writers’ Prize.

That’s a tough act to follow, but Akpan is a natural storyteller, with an amazing ear for dialect and a confident authorial voice.

“People keep asking me about my second book,” he said. “I’m not even sure where the setting will be — maybe Africa … maybe even here.”

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Fundraising event raises over $12 million

On February 26, 2019, the University of Florida raised more than $12.6 million during a daylong event, Stand Up and Holler: Gator Nation Giving Day.

Giving Day, which began at 12 a.m. EST and concluded at 11:59 p.m. PST, drew 11,535 gifts from individuals around the world, including gifts from all 50 states and the giving site visited by people in 73 countries. The College of Liberal Arts and Sciences received 520 gifts totaling over $670,000. By 5 p.m., UF had surpassed its initial goal of 5,000 gifts, and a new goal of
8,500 gifts was set. By 8:30 p.m. that goal was met, and an unofficial new one — 10,000 gifts — was established.

“The gifts we received will have a major impact on our college,” College of Liberal Arts and Sciences Dean David Richardson said. “Stand Up and Holler donors supported inspired programming, innovative research and experiential learning opportunities so that our students and faculty are fully empowered to pursue their passions.”

Driven mostly by email and social media, the campaign was named in recognition of the beloved Gator football game cheer made famous by George Edmondson Jr., better known to fans as “Mr. Two Bits,” who passed away in July 2019.

George “Mr. Two Bits” Edmondson Jr.’s signature striped neck tie was used as a symbol to encourage participation in Stand Up and Holler: Gator Nation Giving Day.

Edmondson’s iconic orange-and-blue striped necktie was used as a symbol to promote the campaign, with T-shirts emblazoned with ties and tie stickers handed out, and replicas as large as 30 feet long strategically placed throughout the Gainesville campus. Six campus events and 20 others in key regions across the country were also held Feb. 26 to further encourage participation.

The College of Liberal Arts and Sciences received further support thanks to ROB KINCART ‘72, his wife Laurel and their family, who donated $100 for every gift made to the college, totaling an additional $52,000.

“My family was very excited to participate in the inaugural Stand Up and Holler: Gator Nation Giving Day,” Kincart said. “We are continuously inspired by the great work of the College of Liberal Arts and Sciences and are proud to support the college’s students, faculty and researchers in all their efforts.”

“We are so thankful for the generosity of donors like the Kincarts,” Dean Richardson said. “Their dedication to this college allows us to provide support for unique programs like Beyond120 so they can give our students the tools they need to succeed not only once they graduate from our college, but for the rest of their lives.”

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UF Oral History Program hosts West Point cadets for a crash course in racial equality

Gainesville was not supposed to be a stop on the 2019 West Point Civil Rights Staff Ride. That was before PAUL ORTIZ, an associate professor of history and director of the Samuel Proctor Oral History Program, got involved.

The Staff Ride steeps West Point cadets in the legacy of civil rights and racial issues through classes and a two-week tour of significant historical sites.

This year, the planned first stop was in Ocoee, Fla., where, on Election Day 1920, white mobs killed an estimated 30-35 African Americans and later drove the rest out of town for trying to cast their votes in the segregated South.

While preparing to lead the trip, Army Lt. Col. LaKeysia R. Harvin, a West Point assistant professor of law who is originally from Gainesville and received her juris doctor from UF, encountered an article Ortiz had written about the massacre. She reached out to him in search of contacts to host the group in Ocoee.

Ortiz, a third-generation military veteran, was eager to help. The idea of versing future officers in civil rights, inclusivity and equality resonated with him personally.

“I thought about my own military experience,” Ortiz said, “and I thought, ‘Wow, I would have loved to work with officers like that.’”

He not only connected Harvin with a civil rights leader and retired Army major in Ocoee, he offered to arrange a second stop for the cadets in Gainesville.

Gainesville panel for West Point Civil Rights Staff Ride
Civil rights movement veterans and activists led a panel for visiting West Point cadets. (Deborah Hendrix)

Engaging with the military is at the core of what the Oral History Program does. The program’s interviewers have talked to hundreds of former servicemen and women for its Veterans History Project.

“We’re not doing our job if we’re just talking to people on campus,” Ortiz said. “Part of our job is to be a bridge between the university and the broader community.”

Ortiz saw the cadets’ visit as a chance to use oral history to prepare future military officers to lead diverse groups while advancing ideals of democracy and equality.

“We want to ensure that people in the military understand the value of what they’re supposed to be upholding,” he said.

On their May 30 stop in Gainesville, the cadets attended a panel at the Wilhelmina Johnson Center featuring local activists and civil rights movement veterans, including UF religion professor Gwendolyn Zoharah Simmons and Vivian Filer, chair of the board of directors at the Gainesville Cotton Club Museum and Cultural Center.

West Point Cadets Civil Rights Brunch
West Point cadets continued their conversation with the panelists over brunch at the Gainesville Cotton Club Museum and Cultural Center. (Deborah Hendrix)

After a van tour that showed the cadets how Gainesville has changed over the years, the group had brunch at the Cotton Club. There, they continued their dialogue with the panelists about issues like gentrification and affordable housing.

The Ocoee and Gainesville visits, it seems, set a high standard for the rest of the Civil Rights Staff Ride.

“The good news is that these were two of the most engaging stops on our entire trip,” Harvin wrote in a thank-you note to Dean David Richardson. “The bad news is that it will be hard for other places to measure up to the hospitality, quality and professionalism we received in Ocoee and Gainesville.”

Click here to see more stories from the Summer 2019 Newsletter. 

Picture of Carolyn Luysterburg
Carolyn Luysterburg, photo byTimothy Sofranko for the College of Liberal Art’s and Sciences

UF Alum Works to Connect Gators

When CAROLYN LUYSTERBURG ’11 was eight, her father took the family on a tour of 20 national parks. Stunned by their beauty, Luysterburg discovered a love for nature and science.

So, when the opportunity came for her to register for a national parks course at the University of Florida 10 years later, she jumped at the chance — and fell in love with geology.

“Geology is the science that you can use to understand all the sciences — math, physics, chemistry and biology — to understand the earth,” Luysterburg said.

Today, Luysterburg is an exploration geologist for the energy company Shell, where she evaluates the feasibility of deep-water wells, while her high school sweetheart-turned-husband, CIRO LUYSTERBURG ’11, works for another major energy company, ExxonMobil.

After graduation the couple relocated to Houston, where Luysterburg launched the UF Houston Geological Society to provide a place for fellow UF alumni to network. With this new outpost of the Gator Nation, she is advancing the sense of connectedness that drew her to UF in the first place.

“I absolutely love the Gator Nation and the spirit,” she said. “I travel internationally for work often and find Gators just about everywhere.”

Luysterburg is especially appreciative of her UF mentor Jon Martin’s advice. Martin, a geology professor who specializes in chemical hydrogeology, encouraged Luysterburg to apply for internships and present at conferences, then continued to be her advisor through grad school.

“He taught me that I can do anything I put my mind to,” Luysterburg said. “Those lessons are still with me today. He made a huge difference in my life.”

She’s proud to be at Shell, where she relishes the opportunity to collaborate with people from around the world.

“There’s just incredible diversity when you work for one of these large international companies like Shell,” Luysterburg said.

In addition to conducting international research at Shell, Luysterburg is actively trying to connect alumni with their alma mater through the UF Houston Geological Society.

“I want to encourage alumni to get involved and give back to department and sponsor students,” Luysterburg said. “We don’t realize when we’re in school, but tons of alumni are continuously supporting us. We need to do the same for the next generation.”

Luysterburg was honored for her efforts when she received the Horizon Award at the college’s Evening of Excellence. The award recognizes professional accomplishment or service to the university by a recent alumnus or alumna.

“UF taught me many things, but my most valuable lesson was learning how to be both a team player and an inspiring leader,” she said. “I am proud to be a Florida Gator, and I hope I can make my university proud too.”

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UF astronomer discovers the previously unknown origin of some asteroids.

Emeritus professor and astronomical theoretician Stan Dermott has made a remarkable discovery about the origin of asteroids.

Dermott, who studies solar system dynamics, has been peering into our Universe with all its cosmic dust and other stuff for 45 years. During his long career at UF, he has made significant discoveries, including one that shows the Sun is ringed by a circle of cosmic dust in which the Earth is embedded.

Astronomers know that some cosmic dust derives from collisions of asteroids — magnificently massive bodies of space rock too airless to be planets — that orbit our Sun.

Dermott, now age 75, has never stopped investigating asteroids, their orbits, and their origins.

Astronomers have access to the orbits of 600,000 asteroids in the inner asteroid belt between Mars and Jupiter. The smashing and crashing of these asteroids deep in space create the majority of meteorites that land on Earth. Dermott kept asking himself one simple question: “Do big asteroids have the same orbit as little asteroids?” Everyone assumed they did.

“Why hasn’t anyone asked this question before?” wondered Dermott. More importantly, since an meteorite strike can change life on Earth as we know it, why hasn’t anyone answered this question?

Dermott and his team analyzed the orbits of 200,000 asteroids in the inner asteroid belt closest to Earth. “By demonstrating that the type of orbit depends on the size of the asteroid, we have shown for the first time that all these asteroids, not just those belonging to a few specific families as previously thought, originate from the splintering of a few large asteroids,” says Dermott. “This transforms our understanding of the origin of the meteorites that have crashed to Earth.”

According to Dermott, five or six huge asteroids created by the gravitational collapse of a protoplanetary disk in the inner asteroid belt produce 85 percent of these meteorites. The other 15 perent may also trace their origins to ancient minor planets which came into being the same time as the Earth.

Dermott’s discovery is published in the June 2018 issue of Nature Astronomy.
“This gives us a clearer understanding of the nature of the primordial bodies that formed all the rocky planets in the solar system, including our home, Earth,” says Dermott. “We’ve made a very important discovery that will influence the future of the field.”

Read more at UF News.

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Cyber attacks target the most vulnerable.

Somewhere in cyberspace, someone is creeping on your Facebook page, studying your LinkedIn account, scoping out your company’s website, and Googling your name. Using information you trust, she is crafting the perfect email, and it’s headed for your inbox. In one click, a split second, you hand over the keys to your little kingdom: passwords, retirement accounts, credit cards. What if this personal crisis became a national crisis? What if you are a top-level politician or the CEO of a multinational corporation? In that case, the livelihood of millions might be at stake, or democracy threatened.

In their interdisciplinary research on phishing, University of Florida Professor of Psychology Natalie Ebner and Professor of Electrical and Computer Engineering Daniela Oliveira have found that older adults are particularly vulnerable to phishing. Those who are leaders of industry or politics are favorite targets for phishing attacks, particularly what’s known as spear phishing — a form of social engineering that uses deception to get someone to reveal personal or financial information, which can then be used fraudulently.

portrait of sweet womanNatalie Ebner


“Cognition alone does not explain why individuals fall for social engineering attacks.”

Older people are high in crystallized intelligence, which is based on experience and ability to see the big picture. But fluid intelligence — how fast our brains process information and how our memory works — declines with age, and that can make older adults susceptible to spear phishing. Ebner’s and Oliveira’s research groups study how susceptible people are to weapons of influence in social engineering. “Cognition alone does not explain why individuals fall for social engineering attacks,” says Ebner. “In fact, our data suggest that low self-reported positive affect, such as feelings of unhappiness or loneliness, constitutes another risk factor, particularly in the oldest individuals.”

Social media, the outlet for manufactured happiness, can be a social engineer’s best friend. Things that seem innocuous, such as employees taking pictures of their cubicles and coworkers, or posting pictures that contain company badges, or clients tagging a company on Twitter or Facebook, provide fodder for phishing attacks. This blending of personal and professional social media works to the social engineer’s advantage.

“Older adults often occupy positions of power in organizations and politics, and thus online deception of these individuals can result in negative consequences with broad societal impact,” Ebner says. Research shows that sensitivity to deception decreases as people age. As people become more trusting, they become more vulnerable.

Read more at UF News.

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A Mellon grant supports discussing tough topics on campus.

Most people shy away from conversations about race, religion, and politics, but UF’s Center for the Humanities and the Public Sphere (CHPS) is inviting them, among other topics, such as technology, ethics, and social justice. The center recently announced the formation of its inaugural Intersections Research-Into-Teaching Grants, made possible with $400,000 in funding from The Andrew W. Mellon Foundation. Awards of $30,000 to four Intersections Groups will support UF faculty and staff working together across disciplines to address major social problems, examine current cultural trends and experiences, and explore next steps in science and technology.

“Importantly, the Intersections Groups will translate scholarship into teaching to expose first-year students to the significance of the humanities in multiple thematic contexts,” says Barbara Mennel, interim director for the center.

Together, these interdisciplinary groups unite 24 faculty and staff members and seven affiliate faculty, from 20 disciplines and six colleges across UF.

A large group of faculty members from the Samuel Proctor Oral History Program, the Center for Gender, Sexualities, and Women’s Studies Research (CGSWSR), African American Studies, Latin American Studies, and African Studies will join forces to discuss the African and Latinx diaspora and develop tools for higher education to improve campus climate and race relations. Anna Peterson of Religion and Jaime Ahlberg of Philosophy will lead a group that will develop a course surrounding contemporary ethical issues, such as First and Second Amendment rights and environmental impact. Whitney Sanford of Religion also is in this group. Jodi Schorb of CGSWSR and Stephanie Birch of African American studies will lead a group that creates dialogue on campus through speaker events and symposia on the topics of mass incarceration and restorative justice. Elizabeth Dale of history and Lauren Pearlman of History and African American Studies also are in this group. Finally, Betty Smocovitis of History and Biology and Eleni Bozia of Classics will lead a group devoted to the use of the “technosphere” to enhance society and the campus experience, as well as illuminate and shape our collective future. Will Hasty and Ying Xiao of Languages, Literatures, and Cultures, and Ken Sassaman of Archaeology, also are in this group.

Says Mennel, “These Intersections Groups demonstrate the urgency for scholars to mobilize interdisciplinary collaboration with the humanities in order to respond to grand challenges.”

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