DALLAS (SMU) – Leaf fossils from Ethiopia’s Mush Valley that date back nearly 22 million years have been found by SMU’s Earth Science professors Bonnie Jacobs and Neil J. Tabor and a dozen other international scientists.
The Mush Valley is the first site in Africa to produce an assemblage of some 2,400 leaves from that time interval, and the first to be studied using multiple lines of evidence, including associated microscopic fossils and chemical constituents, that tell us details about the ancient ecosystem.
Scientists can use data from the study to answer fundamental questions, like what climate change may look like in the future. Specifically, climate scientists can take information from the study, along with other data, to test models used to estimate future global climate change.
“The past helps us to understand how ecological processes operate under conditions so different from now. It is like the Earth has done experiments for us,” said Jacobs, a world-renowned paleobotanist at SMU (Southern Methodist University).
In addition, using fossils to learn more about what Africa’s prehistoric ecosystems were like can provide context for events in the past, such as when a land bridge developed between Africa and Eurasia 24 million years ago or the environment for primate precursors to the human family.
The fossils found in this study span an interval of 60,000 years during the early Miocene Epoch, which began 23 million years ago. Ellen D. Currano, a paleoecologist at the University of Wyoming, was the lead author of the study. It was published in the journal Palaeogeography, Palaeoclimatology, Palaeoecology.
You can read more about the work that Jacobs, Currano and the international colleagues have been doing in the Mush Valley here.
About SMU
SMU is the nationally ranked global research university in the dynamic city of Dallas. SMU’s alumni, faculty and nearly 12,000 students in eight degree-granting schools demonstrate an entrepreneurial spirit as they lead change in their professions, communities and the world.
DALLAS (SMU) – A robotic arm built by mechanical engineering professor Edmond Richer at SMU’s Lyle School of Engineering is delivering a stronger future for young Braden Scott, helping re-create connections between his brain and muscles.
Braden was 5 years old when he came down with acute flaccid myelitis, a rare condition that affects the nervous system.
SMU is the nationally ranked global research university in the dynamic city of Dallas. SMU’s alumni, faculty and nearly 12,000 students in eight degree-granting schools demonstrate an entrepreneurial spirit as they lead change in their professions, communities and the world.
The exhibit has been viewed by 6 million visitors since it opened last year, leading to Smithsonian granting a longer stay for the exhibit in the Washington, D.C. museum. It was originally supposed to leave next year. Smithsonian also asked for an additional exhibit window for “Sea Monsters Unearthed,” showcasing the international and interdisciplinary collaboration that went into discovering the fossils.
The exhibit showcases never-before-seen fossils from Angola that was made possible largely due to the work of SMU vertebrate paleontologist Louis Jacobs and his colleagues and undergraduates. SMU Emeritus Professor of Paleontology Louis Jacobs and his SMU colleague Michael Polcyn forged a partnership with collaborators in Angola, Portugal and the Netherlands to explore and excavate Angola’s rich fossil history, while laying the groundwork for returning the fossils to the West African nation. Back in Dallas, Jacobs and Polcyn, director of the University’s Digital Earth Sciences Lab, and research associate Diana Vineyard went to work over a period of 13 years with a small army of SMU students to prepare the fossils excavated by Projecto PaleoAngola. These students – including Myria Perez, a former paleontology student who is now a fossil preparator at the Perot Museum – worked in basement laboratories to painstakingly clean and preserve the fossils.
“Sea Monsters Unearthed” allows visitors to visually dive into the cool waters off the coast of West Africa as they existed millions of years ago when the continents of Africa and South America were drifting apart. It’s a unique opportunity to examine fossils of ancient marine reptiles and learn about the forces that continue to mold life both in out of the ocean.
After 2021, the exhibit will return to Angola. Learn more here.
About SMU
SMU is the nationally ranked global research university in the dynamic city of Dallas. SMU’s alumni, faculty and nearly 12,000 students in seven degree-granting schools demonstrate an entrepreneurial spirit as they lead change in their professions, communities and the world.
About the National Museum of Natural History
The National Museum of Natural History is connecting people everywhere with Earth’s unfolding story. The museum is one of the most visited natural history museums in the world with approximately 7 million annual visitors from the U.S. and around the world. Opened in 1910, the museum is dedicated to maintaining and preserving the world’s most extensive collection of natural history specimens and human artifacts. It is open daily from 10 a.m. to 5:30 p.m. (closed Dec. 25). Admission is free. For more information, visit the museum on its website and on Facebook and Twitter.
DALLAS (SMU) – It takes a tremendous amount of computer simulations to create a device like an MRI scanner that can image your brain by detecting electromagnetic waves propagating through tissue. The tricky part is figuring out how electromagnetic waves will react when they come in contact with the materials in the device.
SMU researchers have developed an algorithm that can be used in a wide range of fields – from biology and astronomy to military applications and telecommunications – to create equipment more efficiently and accurately.
Currently, it can take days or months to do simulations. And because of cost, there is a limit to the number of simulations typically done for these devices. SMU math researchers have revealed a way to do a faster algorithm for these simulations with the help of grants from the U.S. Army Research Office and the National Science Foundation.
“We can reduce the simulation time from one month to maybe one hour,” said lead researcher Wei Cai, Clements Chair of Applied Mathematics at SMU. “We have made a breakthrough in these algorithms.”
“This work will also help create a virtual laboratory for scientists to simulate and explore quantum dot solar cells, which could produce extremely small, efficient and lightweight solar military equipment,” said Dr. Joseph Myers, Army Research Office mathematical sciences division chief.
Dr. Bo Wang, a postdoctoral researcher at SMU (Southern Methodist University) and Wenzhong Zhang, a graduate student at the university, also contributed to this research. The study was published today by the SIAM Journal on Scientific Computing and can be viewed here.
The algorithm could have significant implications in a number of scientific fields.
“Electromagnetic waves exist as radiation of energies from charges and other quantum processes,” Cai explained.
They include things like radio waves, microwaves, light and X-rays. Electromagnetic waves are also the reason you can use a mobile phone to talk to someone in another state and why you can watch TV. In short, they’re everywhere.
An engineer or mathematician would be able to use the algorithm for a device whose job is to pick out a certain electromagnetic wave. For instance, she or he could potentially use it to design a solar light battery that lasts longer and is smaller than currently exists.
“To design a battery that is small in size, you need to optimize the material so that you can get the maximum conversion rate from the light energy to electricity,” Cai said. “An engineer could find that maximum conversion rate by going through simulations faster with this algorithm.”
Or the algorithm could help an engineer design a seismic monitor to predict earthquakes by tracking elastic waves in the earth, Cai noted.
“These are all waves, and our method applies for different kinds of waves,” he said. “There are a wide range of applications with what we have developed.”
Computer simulations map out how materials in a device like semiconductor materials will interact with light, in turn giving a sense of what a particular wave will do when it comes in contact with that device.
The manufacturing of many devices involving light interactions uses a fabrication process by layering material on top of each other in a lab, just like Legos. This is called layered media. Computer simulations then analyze the layered media using mathematical models to see how the material in question is interacting with light.
More Efficient, Less Expensive Way to Solve Helmholtz and Maxwell’s Equations
SMU researchers have found a more efficient and less expensive way to solve Helmholtz and Maxwell’s equations – difficult to solve but essential tools to predict the behavior of waves.
The problem of wave source and material interactions in the layer structure has been a very challenging one for the mathematicians and engineers for the last 30 years.
Professor Weng Cho Chew from Electrical and Computer Engineering at Purdue, a world leading expert on computational electromagnetics, said the problem “is notoriously difficult.”
Commenting on the work of Cai and his team, Chew said, “Their results show excellent convergence to small errors. I hope that their results will be widely adopted.”
The new algorithm modifies a mathematical method called the fast multipole method, or FMM, which was considered one of the top 10 algorithms in the 20th century.
To test the algorithm, Cai and the other researchers used SMU’s ManeFrame II – which is one of the fastest academic supercomputers in the nation – to run many different simulations.
SMU is the nationally ranked global research university in the dynamic city of Dallas. SMU’s alumni, faculty and nearly 12,000 students in seven degree-granting schools demonstrate an entrepreneurial spirit as they lead change in their professions, communities and the world.
An estimated 10 to 15 million people are infected with HTLV-1, which is a cousin of HIV
DALLAS (SMU) – A study led by SMU suggests that oleandrin – a drug derived from the Nerium oleander plant – could prevent the HTLV-1 virus from spreading by targeting a stage of the reproduction process that is not currently targeted by existing drugs.
That is significant because there is currently no cure or treatment for the virus – a lesser-known “cousin” of HIV that affects an estimated 10 to 15 million people worldwide.
“Our research findings suggest that oleandrin could possibly limit the transmission and spread of HTLV-1 by targeting a unique stage in the retroviral life cycle,” said Robert Harrod, associate professor and director of Graduate Studies in SMU’s Department of Biological Sciences. Harrod is a co-author of the study, published in the Journal of Antivirals & Antiretrovirals.
The human T-cell leukemia virus type-1, or HTLV-1, is a retrovirus that infects white blood cells known as T-cells and is usually transmitted in a similar manner to HIV-1 through a person’s blood or body fluid. Infected cells present within breast milk can also pass HTLV-1 from mother to infant through breastfeeding.
While HIV-1 kills the infected T-cells, HTLV-1 causes them to divide uncontrollably. This in turn can lead to the development of aggressive leukemia – a cancer of the white blood cells. People infected with HTLV-1 can also develop a progressive neurological disease known as HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP), a progressive inflammatory disease of the nervous system that can affect one’s ability to walk and may cause serious symptoms leading to coma and even death.
Retrovirus particles copy themselves within infected cells by transcribing their RNA into DNA after entering a cell, a process called the retroviral life cycle. The more virus-infected cells that are produced, the worse symptoms can get for people who are infected with HTLV-1.
The two lead authors, Tetiana Bowley and Lacin Yapindi, are Ph.D graduate students who worked with Harrod in his lab. Aditi Malu, who also worked in Harrod’s lab, graduated from SMU with a PhD in May. Together with collaborator Jagan Sastry at the University of Texas M.D. Anderson Cancer Center and Dr. Robert Newman at Phoenix Biotechnology, Inc., SMU researchers found that the botanical compound called oleandrin successfully interrupted part of the infection cycle for HTLV-1.
“As has been shown for HIV-1, treatment with oleandrin did not affect the ability of infected cells to produce and release new virus particles. However, the particles that were produced were defective, meaning they contained less envelope glycoprotein on their surface,” Harrod said. “This impaired their ability to form virological synapses for effective cell-to-cell virus transmission.”
A so-called “envelope,” which forms the outer coat of the HTLV-1 particle and binds to the receptors on the surface of target cells, must be present in order for a virus-infected cell to fuse with the membrane of an uninfected T-cell, allowing the virus to enter the cell and spread the disease. Without it, the HTLV-1 retrovirus can’t successfully be passed to other cells.
“Oleandrin is unique in its ability to block the incorporation of the envelope glycoprotein into mature virus particles as they’re exiting an infected cell,” Harrod said.
The hope is that oleandrin, or a similar drug that targets the same part of the retrovirus infection cycle, could potentially prevent HTLV-1 from causing progressively worse clinical symptoms in people with an immune-driven condition like HAM/TSP where the body’s immune system causes tissue damage due to the misrecognition of replicating virus particles.
“If a drug, such as oleandrin, could prevent the spread of HTLV-1 particles within an infected HAM/TSP patient, it may become possible to dampen the neuroinflammatory response to alleviate the symptoms of disease,” Harrod said.
Harrod called the findings “exciting” because oleandrin targets a different mechanism of fighting the virus – one that hasn’t been the focus of other antiviral drugs that attack specific steps in the retroviral infection cycle. Those drugs, called highly-active antiretroviral therapies or HAART for short, have not been shown to be effective with HTLV-1.
In the study, to demonstrate that purified oleandrin or an N. oleander extract could inhibit the formation of HTLV-1 virological synapses, SMU researchers in Harrod’s lab labeled an HTLV-1-infected virus-producing cell-line with green fluorescent protein (GFP), so these cells could be easily identified by their ‘green’ fluorescence under a microscope. These cells were then placed in the same culture well as healthy T-cells. T-cells that became infected with HTLV-1 were easy to spot because researchers could see a junction between the two cells and then a red fluorescent signal showing up in the newly-infected T-cell.
Phoenix Biotechnology provided the purified oleandrin and Nerium oleander plant extract used in the study.
SMU is the nationally ranked global research university in the dynamic city of Dallas. SMU’s alumni, faculty and nearly 12,000 students in seven degree-granting schools demonstrate an entrepreneurial spirit as they lead change in their professions, communities and the world.