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‘Oumuamua Interstellar Object Was Not an Alien Spacecraft

July 1, 2019
Contacts: 

 

Matthew Wright 301-405-9267

Artist’s concept of ‘Oumuamua. Image credit: ESO/M. Kornmesser (Click image to download hi-res version.)

COLLEGE PARK, Md. On October 19, 2017, astronomers discovered the first known interstellar object to visit our solar system. Early reports of the odd characteristics of “‘Oumuamua” led to speculation that the object might be an alien spacecraft. Now a new analysis by an international team of astronomers co-led by, University of Maryland Associate Research Scientist Matthew Knight, strongly indicates that its origin is purely natural.

When first spotted by the Panoramic Survey Telescope and Rapid Response System 1 telescope located at the University of Hawaii’s Haleakala Observatory, the object defied easy description, simultaneously displaying characteristics of both a comet and an asteroid. Astronomers formally named the object 1I/2017 U1 and with a common name of ‘Oumuamua, which roughly translates to “scout” in Hawaiian. 

Researchers from UMD and around the world immediately raced to collect as much data as possible in the few weeks they had  to observe the strange visitor before ‘Oumuamua traveled beyond the reach of Earth’s telescopes.  The new findings by Knight and colleagues from some 13 institutions and five countries are reported  in the July 1, 2019, issue of the journal Nature Astronomy.

“We have never seen anything like ‘Oumuamua in our solar system. It’s really a mystery still,” Knight said. “But our preference is to stick with analogs we know, unless or until we find something unique. The alien spacecraft hypothesis is a fun idea, but our analysis suggests there is a whole host of natural phenomena that could explain it.”

As Knight and his colleagues summarized in their study, ‘Oumuamua is red in color, similar to many small objects observed in our solar system. But that’s where the familiarity ends.

‘Oumuamua likely has an elongated, cigarlike shape and an odd spin pattern—much like a soda bottle laying on the ground, spinning on its side. According to Knight, its motion through our solar system is particularly puzzling. While it appeared to accelerate along its trajectory—a typical feature of comets—astronomers could find no evidence of the gaseous emissions that typically create this acceleration.

“The motion of ‘Oumuamua didn’t simply follow gravity along a parabolic orbit as we would expect from an asteroid,” Knight said. “But visually, it hasn’t ever displayed any of the cometlike characteristics we’d expect. There is no discernable coma—the cloud of ice, dust and gas that surrounds active comets—nor a dust tail or gas jets.”

Knight worked with Alan Fitzsimmons, an astronomer at Queen’s University Belfast in Northern Ireland, to assemble a team of 14 astronomers hailing from the U.S. and Europe. The International Space Science Institute in Bern, Switzerland, served as a virtual home base for the collaboration.

“We put together a strong team of experts in various different areas of work on ‘Oumuamua. This cross-pollination led to the first comprehensive analysis and the best big-picture summary to date of what we know about the object,” Knight explained. “We tend to assume that the physical processes we observe here, close to home, are universal. And we haven’t yet seen anything like ‘Oumuamua in our solar system. This thing is weird and admittedly hard to explain, but that doesn’t exclude other natural phenomena that could explain it.”

The new research paper is primarily an analysis of existing data, including of a December 2017 study of ‘Oumuamua’s shape and spin pattern co-authored by Knight and a team of UMD astronomers. This earlier paper, published in The Astrophysical Journal Letters, relied on data from the Discovery Channel Telescope (DCT) at the Lowell Observatory in Arizona. UMD is a scientific partner of the DCT, along with Boston University, the University of Toledo and Northern Arizona University. 

Knight, Fitzsimmons and their colleagues considered a number of mechanisms by which ‘Oumuamua could have escaped from its home system. For example, the object could have been ejected by a gas giant planet orbiting another star. According to theory, Jupiter may have created the Oort cloud—a massive shell of small objects at the outer edge of our solar system—in this way. Some of those objects may have slipped past the influence of the sun’s gravity to become interstellar travelers themselves.

The research team suspects that ‘Oumuamua could be the first of many interstellar visitors. Knight is looking forward to data from the Large Synoptic Survey Telescope (LSST), which is scheduled to be operational in 2022.

“In the next 10 years, we expect to begin seeing more objects like ‘Oumuamua. The LSST will be leaps and bounds beyond any other survey we have in terms of capability to find small interstellar visitors,” Knight said. “We may start seeing a new object every year. That’s when we’ll start to know whether ‘Oumuamua is weird, or common. If we find 10-20 of these things and ‘Oumuamua still looks unusual, we’ll have to reexamine our explanations.”

The research paper, “The Natural History of ‘Oumuamua,” the ‘Oumuamua ISSI Team (Michele Bannister, Asmita Bhandare, Piotr Dybczyński, Alan Fitzsimmons, Aurélie Guilbert-Lepoutre, Robert Jedicke, Matthew Knight, Karen Meech, Andrew McNeill, Susanne Pfalzner, Sean Raymond, Colin Snodgrass, David Trilling and Quanzhi Ye), was published in the journal Nature Astronomy on July 1, 2019.

The December 2017 research paper on the object by the UMD research team was, “On the Rotation Period and Shape of the Hyperbolic Asteroid 1I/‘Oumuamua (2017 U1) from Its Lightcurve,” Matthew Knight, Silvia Protopapa, Michael Kelley, Tony Farnham, James Bauer, Dennis Bodewits, Lori Feaga and Jessica Sunshine, was published in The Astrophysical Journal Letters.

This work was supported by the UK Science and Technology Facilities Council (Award Nos. ST/P0003094/1 and ST/L004569/1), the National Science Foundation (Award Nos. AST1617015 and 1545949), NASA (Award Nos.  GO/DD-15405, GO/DD-15447, NAS 5-26555, NNX17AK15G and 80NSSC18K0829), the National Science Centre in Poland (Award No. 2015/17/B/ST9/01790) and the European Research Council (Award No. 802699). The content of this article does not necessarily reflect the views of these organizations.

University of Maryland, University System of Maryland, and Board of Regents Joint Statement on MSCHE Accreditation Decision-- June 28, 2019

June 28, 2019

Joint Statement by University System of Maryland (USM) Board of Regents Chair Linda Gooden, USM Chancellor Robert Caret, and University of Maryland College Park (UMCP) President Wallace Loh on the Decision by the Middle States Commission of Higher Education (MSCHE) Regarding the Accreditation Status of UMCP:

 

MSCHE on June 27, 2019 placed UMCP on warning that “its accreditation may be in jeopardy because of insufficient evidence that [it] is currently in compliance with Standard VII (Governance, Leadership, and Administration).” This Standard requires that UMCP “operate as an academic institution with appropriate autonomy.” 

Therefore, MSCHE requested a monitoring report due March 1, 2020, demonstrating compliance with Standard VII, followed-up by a MSCHE team visit. MSCHE will provide guidance on its expectations. Meanwhile, UMCP remains fully accredited. 

USM Board of Regents, USM, and UMCP are committed to working together to ensure that the governance structure clearly specifies the roles, responsibilities, and accountability of each constituency and that these are in full alignment with MSCHE Standard VII; moreover, that there is periodic assessment of the effectiveness of governance, leadership, and administration in accordance with Standard VII. Progress towards full compliance is already underway and will be completed by March 1, 2020. 

 

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University of Maryland, City of College Park to Host Fourth of July Celebration

June 27, 2019
Contacts: 

University of Maryland: Natifia Mullings, 301-405-4076
City of College Park: Ryna Quinones, 240-487-3508

COLLEGE PARK, Md. – The University of Maryland and the City of College Park will host its annual Independence Day celebration on Thursday, July 4 from 5 to 10 p.m. at the University of Maryland, Lot 1 (adjacent to Campus Drive off Adelphi Road). The celebration will include a free concert by The Nightlife Band followed by a 30-minute fireworks show.  Food will also be available for purchase. 

Schedule of activities include:

  • Concessions open at 5 p.m.
  • Entertainment begins at 7 p.m.
  • Fireworks start at 9 p.m.

Grass seating is limited. Attendees are encouraged to bring lawn chairs and blankets. Personal coolers are also allowed. 

In the event of inclement weather, the fireworks show will be held on Friday, July 5 at 9 p.m. For more information, click here

 

Perfect Quantum Portal Emerges at Exotic Interface

June 19, 2019
Contacts: 

Chris Cesare 301-405-0824

COLLEGE PARK, Md. – Researchers at the University of Maryland have captured the most direct evidence to date of a quantum quirk that allows particles to tunnel through a barrier like it’s not even there. The result, which is featured on the cover of the June 20 issue of Nature, may enable engineers to design more uniform components for future quantum computers, quantum sensors and other devices.

The new experiment is an observation of quantum (Klein) tunneling, a special case of a more ordinary quantum phenomenon. In the quantum world, tunneling allows particles like electrons to pass through a barrier even if they don’t have enough energy to actually climb over it. A taller barrier usually makes this harder and lets fewer particles through.

Klein tunneling occurs when the barrier becomes completely transparent, opening up a portal that particles can traverse regardless of the barrier’s height. Scientists and engineers from the Center for Nanophysics and Advanced Materials(CNAM), the Joint Quantum Institute (JQI) and the Condensed Matter Theory Center (CMTC), with appointments in materials science and engineering, as well as physics, have made the most compelling measurements yet of the effect.

“Klein tunneling was originally a relativistic effect, first predicted almost a hundred years ago,” said Ichiro Takeuchi, a UMD professor of materials science and engineering (MSE) and the senior author of the new study. “Until recently, though, you could not observe it.”

It was nearly impossible to collect evidence for Klein tunneling where it was first predicted—the world of high-energy quantum particles moving close to the speed of light. But in the past several decades, scientists have discovered that some of the rules governing fast-moving quantum particles also apply to the (comparatively) sluggish particles traveling near the surface of some unusual materials.

One such material—which researchers used in the new study—is samarium hexaboride (SmB6), a substance that becomes a topological insulator at low temperatures. In a normal insulator like wood, rubber or air, electrons are trapped, unable to move even when a voltage is applied. Thus, unlike their free-roaming comrades in a metal wire, electrons in an insulator can’t conduct a current.

Topological insulators such as SmB6 behave like hybrid materials. At low enough temperatures, the interior of SmB6 is an insulator, but the surface is metallic and gives electrons some freedom to move around. Additionally, the direction that the electrons move becomes locked to an intrinsic quantum property called spin that can be oriented up or down. Electrons moving to the right will always have their spin pointing up, for example, and electrons moving left will have their spin pointing down.

The metallic surface of SmB6 would not have been enough to spot Klein tunneling, though. It turns out that Takeuchi and colleagues needed to transform the surface of SmB6 into a superconductor—a material that can conduct electrical current without any resistance.

To do this, they put a thin film of SmB6 atop a layer of yttrium hexaboride (YB6). When the whole assembly was cooled to just a few degrees above absolute zero, the YB6 became a superconductor, and, due to its proximity, the metallic surface of SmB6 became a superconductor, too.

It was a “piece of serendipity” that SmB6 and its yttrium-swapped relative shared the same crystal structure, said Johnpierre Paglione, a coauthor of the new paper who is a physics professor at UMD and the director of CNAM. “However, the multidisciplinary team we have was one of the keys to this success,” Paglione said. “Having experts on topological physics, thin-film synthesis, spectroscopy and theoretical understanding really got us to this point.”

The combination proved the right mix to observe Klein tunneling. By bringing a tiny metal tip into contact with the top of the SmB6, the team measured the transport of electrons from the tip into the superconductor. They observed a perfectly doubled conductance—a measure of how the current through a material changes as the voltage across it is varied.

“When we first observed the doubling, I didn’t believe it,” Takeuchi said. “After all, it is an unusual observation, so I asked my postdoc Seunghun Lee and research scientist Xiaohang Zhang to go back and do the experiment again.”

When Takeuchi and his experimental colleagues convinced themselves that the measurements were accurate, they didn’t initially understand the source of the doubled conductance. So they started searching for an explanation. It was Victor Galitski, a JQI Fellow, UMD physics professor and member of CMTC, who suggested that Klein tunneling might be involved. “At first, it was just a hunch,” Galitski said. “But over time we grew more convinced that the Klein scenario may actually be the underlying cause of the observations.”

UMD research scientist Valentin Stanev took Galitski’s hunch and worked out a careful theory of how Klein tunneling could emerge in the SmB6 system—ultimately making predictions that matched the experimental data well.

The theory suggested that Klein tunneling manifests itself in this case as a perfect form of Andreev reflection, an effect present at all metal-superconductor boundaries. Andreev reflection can occur whenever an electron from the metal hops onto a superconductor. Inside the superconductor, electrons are forced to live in pairs, so when an electron hops on, it picks up a buddy.

In order to balance the electric charge before and after the hop, a particle with the opposite charge—which scientists call a hole—must reflect back into the metal. This is the hallmark of Andreev reflection: an electron goes in, a hole comes back out. And since a hole moving in one direction carries the same current as an electron moving in the opposite direction, this whole process doubles the overall conductance—the signature of Klein tunneling through a junction of metal and a topological superconductor

In conventional metal-superconductor junctions, there are always some electrons that don’t hop onto the superconductor. They scatter off the boundary, reducing the amount of Andreev reflection and preventing an exact doubling of the conductance.

But because the electrons in the surface of SmB6 have their direction of motion tied to their spin, electrons near the boundary can’t bounce back—meaning that they will always transit straight into the superconductor.

“Klein tunneling had been seen in graphene as well,” Takeuchi said. “But here, because it’s a superconductor, I would say the effect is more spectacular. You get this exact doubling and a complete cancellation of the scattering, and there is no analog of that in the graphene experiment.”

Junctions between superconductors and other materials are ingredients in some proposed quantum computer architectures, as well as in precision sensing devices. The bane of these components has always been that each junction is slightly different, Takeuchi said, requiring endless tuning and calibration to reach the best performance. But with Klein tunneling in SmB6, researchers might finally have an antidote to that irregularity.

“In electronics, you know, device-to-device spread is the number one enemy,” Takeuchi said. “Here is a phenomenon that gets rid of the variability.”

The paper had 8 authors in addition to Takeuchi, Paglione, Lee, Zhang, Galitski and Stanev: Drew Stasak, a former research assistant in MSE; Jack Flowers, a former graduate student in MSE; Joshua S. Higgins, a research scientist in CNAM and the department of physics; Sheng Dai, a research fellow in the department of chemical engineering and materials science at the University of California, Irvine (UCI); Thomas Blum, a graduate student in physics and astronomy at UCI; Xiaoqing Pan, a professor of chemical engineering and materials science and of physics and astronomy at UCI; Victor M. Yakovenko, a JQI Fellow, professor of physics at UMD and a member of CMTC; and Richard L. Greene, a professor of physics at UMD and a member of CNAM.

University of Maryland Ranked No. 5 in the Country Among Best Colleges for LGBTQ+ Students

June 17, 2019
Contacts: 
 

Jennifer Burroughs 301-405-4621

 

COLLEGE PARK, Md.  The University of Maryland has been ranked the fifth best college in the nation for LGBTQ+ students, rising two spots from a previous listing. In a collaborative ranking with Campus Pride and Best Colleges, UMD continues to demonstrate its strong commitment to the LGBTQ+ community.

The joint ranking combines Best Colleges’ academic and affordability metrics and the Campus Pride Index Score, which measures LGBTQ-friendly campus life in a national rating system. Only universities with an above average rating, indicating excellent performance in all eight of the LGBTQ-inclusive factors on the Campus Pride Index, were considered.

“This recognition acknowledges our institutional commitment to become a fully equitable community that supports our LGBTQ+ populations,” said Luke Jensen, Ph.D., director, LGBT Equity Center. “It also indicates academic and affordable qualities that make our campus a great option for LGBTQ+ students. ” Jensen continued, “Our commitment to becoming a fully equitable campus is strong. We will persist in seeking new and innovative strategies to address issues that may diminish our most vulnerable populations, especially transgender people and LGBTQ+ people of color.”

UMD’s LGBT Equity Center was featured prominently in the university’s evaluation, which cited access to support groups, peer counseling services, resources for trangender students and information about health care. Other Center-led programs also contributed to the ranking:

  • The Rainbow Terrapin Network focused recently on a TransTerps Campaign. This effort offers tools for offices and student groups to assess and continuously improve their good practices for trans inclusion on campus. Dozens of departments and groups on campus have accessed their resources and are working to improve the climate for trans and nonbinary people.

  • The Lavender Leadership Honor Society, a first-of-its-kind collegiate leadership honor society, focuses on LGBTQ+ social justice. The society has inducted over 100 UMD students, staff, faculty, and alumni. Honorary inductions have included notable figures such as Eboné Bell, founder of the lesbian and queer focused Tagg Magazine, and Urooj Arshad, LGBTQ+ Muslim advocate.

  • Since 2015, UMD's LGBT Equity Center in collaboration with Education Abroad has hosted the Somewhere Over the Rainbow conference biennially. This symposium is a professional development on sexual orientation and gender identity in international education. Participants have come from  throughout the U.S. and from Europe, Asia, and Latin America.

For more information on UMD’s LGBT Equity Center, visit: https://lgbt.umd.edu/

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Responding to Adenovirus and Mold at the University of Maryland

June 7, 2019

Overview

  • We remain deeply saddened by the death of one of our students, Olivia Paregol. Olivia’s death is a tragedy, and our hearts and our thoughts have been with Olivia’s family and friends since her passing.
  • The university is confident that we exceeded public health practices in the handling of adenovirus on our campus. Our approach to reporting, coordinating with health officials, and communicating with our campus community exceeded Centers for Disease Control (CDC) guidelines.
  • Vice President for Student Affairs Linda Clement requested an external review of protocols, policies, procedures and responses to adenovirus cases. The findings support the university’s approach.
  • Among our many actions regarding mold in campus buildings, we consulted with and followed the recommendations of the University of Maryland Department of Environmental Safety, Sustainability and Risk; the US Environmental Protection Agency (EPA); and the US Occupational Safety and Health Administration (OSHA) regarding mold remediation practices.
  • Plans for moisture control include upgrades to our HVAC systems and installing additional dehumidifiers. These actions are underway in an effort to reduce mold in the future.

Click here for more information.

UMD Researcher Develops Digital Preschool Curriculum to Improve Early Childhood Learning

June 6, 2019
Contacts: 

Audrey Hill 301-405-3468

COLLEGE PARK, Md. – Early childhood is a critical time for brain development, and sets the stage for long-term academic success. A new, robust digital curriculum developed for four-year-olds by the University of Maryland, in collaboration with the Maryland State Department of Education and the Smithsonian’s National Museum of American History, is being implemented in hundreds of classrooms across Maryland. The curriculum will ultimately be made available for free to licensed child care programs and public preschool teachers in Maryland, allowing access to high quality early child education regardless of resources.

Developed by University of Maryland researchers, former teachers, and graduate students, the “Children Study Their World” curriculum is based on the principles of project-based inquiry, with lesson plans for eight project topics that are tangible to preschoolers provided as digital books and made available on iPad. Lessons are bolstered by digitized versions of the National Museum of American History’s artifacts, using items like a skeleton marionette and a nurse’s satchel straight from the renowned museum’s collection to enhance learning.

The UMD Center for Early Childhood Education and Intervention leads the curriculum project, which has been rolled out in 61 classrooms this year and will be implemented in 200 Maryland classrooms next school year.

The Children Study Their World curriculum fully aligns with Maryland’s Early Learning Assessment and Early Learning Standards, which means that children receive instruction throughout the year in all content areas outlined in the standards, such as literacy and math.

Brain research demonstrates the importance of providing young children with rich, hands-on learning experiences respectful of their capacity to learn and eagerness to explore, said Center for Early Childhood Education and Intervention Executive Director Christy Tirrell-Corbin, PhD, who is also the principal investigator and director of the curriculum project.

“We chose project topics like ‘My Body’ and ‘All Aboard: Transportation’ for the children to investigate, as 4-year-olds are very concrete in their thinking and benefit from studying the world that surrounds them every single day,” she said. “Through project-based inquiry, the children’s interests help direct the learning on these topics, which also includes small group learning, field trips and classroom visits from experts,”  Tirrell-Corbin said.

Each of the interdisciplinary projects include digitized, child-friendly pieces from the Smithsonian collection that serve as the base of an “object investigation”—small group lessons written by Smithsonian staff who worked with the curriculum team.

“Collaborating with CECEI to produce ‘Children Study their World’ is an important part of our museum’s ongoing early learning initiative,” said Carrie C. Kotcho, A. James Clark Director of Education & Impact at the museum. “With this curriculum, our museum educators were able to integrate digitized objects from the National Museum of American History’s collections and share expertise on how to engage children with enjoyable learning experiences that support literacy and school readiness, play and inquiry, and the development of executive function skills.”

“Whether at Wegman’s Wonderplace, our play-based early learning space, in communities, or through digital curriculums like “Children Study their World,” we are dedicated to helping our youngest learners explore, learn and succeed,” said Kotcho.

Available on iPad, the guides enable the digital curriculum to be widely disseminated to licensed child care programs and public preschool teachers in Maryland, provide strategies for students with disabilities and English language learners.

"The most important component to a quality pre-K program is the teacher. The teacher needs to be equipped with the tools to deliver high-quality instruction," said Karen Salmon, Maryland State Superintendent of Schools. "This new integrated curriculum and the training and coaching that accompany it helps to ensure this happens."  

In addition to the 200-classroom rollout, Tirrell-Corbin will host a podcast series focused on high-quality instructional practices for early-childhood teachers next year, and Children Study Their World staff will facilitate webinars for teachers and for coaches and program administrators.

“Children Study Their World” is a wonderful tool for teaching young children, said Patricia Aburn, a quality assurance specialist and credentialing liaison of the Maryland State Department of Education, who helps coach teachers to use the curriculum.

“Young children are like sponges their first five years,” Aburn said. “They need to be challenged, stimulated by free play and structured whole group and small group activities. They need to be socially engaged and exposed to language through rich vocabulary and stimulating literacy.”

 

Glacial Sediments Greased the Gears of Plate Tectonics

June 6, 2019

COLLEGE PARK, Md. – Earth’s fractured outer shell is composed of giant plates of solid rock that move —grinding together, sliding past or dipping beneath one another to create the mountain ranges and other major surface features of our planet and generating earthquakes, volcanoes, tsunamis and other powerful events. However, Earth’s surface has not always experienced these “plate tectonics” and questions about when this began and how it has changed through time have been much debated by scientists.

New research by University of Maryland and German geologists indicates that the transition to plate tectonics started around 635 million years ago at the end of Earth’s last period of being all or mostly ice covered. Their work suggests that at this point these giant plates began to move, lubricated by sediments that were scraped by glaciers from the slopes of Earth’s first continents. As these sediments collected along the world’s young coastlines, they helped to accelerate the motion of newly formed subduction faults, where a thinner oceanic plate dips beneath a thicker continental plate.

From Solid Shell to Moving Plates

Early in Earth’s history, the planet was covered by a single shell dotted with volcanoes—much like the surface of Venus today. As Earth cooled, this shell began to fold and crack, eventually creating Earth’s system of plate tectonics.

The new study, published June 6, 2019 in the journal Nature, is the first to suggest a role for sediments in the emergence and evolution of global plate tectonics. Michael Brown, a professor of geology at the University of Maryland, co-authored the research paper with Stephan Sobolev, a professor of geodynamics at the GFZ German Research Centre for Geosciences in Potsdam.

The findings suggest that sediment lubrication controls the rate at which Earth’s crust grinds and churns. Sobolev and Brown found that two major periods of worldwide glaciation, which resulted in massive deposits of glacier-scrubbed sediment, each likely caused a subsequent boost in the global rate of plate tectonics.

The most recent such episode followed the “snowball Earth” that ended sometime around 635 million years ago, resulting in Earth’s modern plate tectonic system.

“Earth hasn’t always had plate tectonics and it hasn’t always progressed at the same pace,” Brown said. “It’s gone through at least two periods of acceleration. There’s evidence to suggest that tectonics also slowed to a relative crawl for nearly a billion years. In each case, we found a connection with the relative abundance—or scarcity—of glacial sediments.”

Just as a machine needs grease to keep its parts moving freely, plate tectonics operates more efficiently with lubrication. While it may be hard to confuse the gritty consistency of clay, silt, sand and gravel with a slippery grease, the effect is largely the same at the continental scale, in the ocean trenches where tectonic plates meet.

“The same dynamic exists when drilling Earth’s crust. You have to use mud—a very fine clay mixed with water or oil—because water or oil alone won’t work as well,” Brown said. “The mud particles help reduce friction on the drill bit. Our results suggest that tectonic plates also need this type of lubrication to keep moving.”

Previous research on the western coast of South America was the first to identify a relationship between sediment lubrication and friction along a subduction fault. Off the coast of northern Chile, a relative lack of sediment in the fault trench creates high friction as the oceanic Nazca plate dips beneath the continental South America plate. This friction helped to push the highest peaks of the central Andes Mountains skyward as the continental plate squashed and deformed.

In contrast, further south there is a higher sediment load in the trench, resulting in less friction. This caused less deformation of the continental plate and, consequently, created smaller mountain peaks. But these findings were limited to one geographic area.

For their study, Sobolev and Brown used a geodynamic model of plate tectonics to simulate the effect of sediment lubrication on the rate of subduction. To verify their hypothesis, they checked for correlations between known periods of widespread glaciation and previously published data that indicate the presence of continental sediment in the oceans and trenches. For this step, Sobolev and Brown relied on two primary lines of evidence: the chemical signature of the influence of continental sediments on the chemistry of the oceans and indicators of sediment contamination in subduction-related volcanoes, much like those that make up today’s “ring of fire” around the Pacific Ocean.

According to Sobolev and Brown’s analysis, plate tectonics likely emerged on Earth between 3 and 2.5 billion years ago, around the time when Earth’s first continents began to form. This time frame also coincides with the planet’s first continental glaciation.

A major boost in plate tectonics then occurred between 2.2 to 1.8 billion years ago, following another global ice age that scrubbed massive amounts of sediments into the fault trenches at the edges of the continents.

The next billion years, from 1.75 billion to 750 million years ago, saw a global reduction in the rate of plate tectonics. This stage of Earth’s history was so sedate, comparatively speaking, that it earned the nickname “the boring billion” among geologists.

Later, following the global “snowball Earth” glaciation that ended roughly 635 million years ago, the largest surface erosion event in Earth’s history may have scrubbed more than a vertical mile of thickness from the surface of the continents. According to Sobolev and Brown, when these sediments reached the oceans, they kick-started the modern phase of active plate tectonics.

The research paper, “Surface erosion events controlled the evolution of plate tectonics on Earth,” Stephan Sobolev and Michael Brown, was published in the journal Nature on June 6, 2019.

 

University of Maryland Partner, College Park Academy, Celebrates First Graduating High School Class

June 5, 2019
Contacts: 

Natifia Mullings 301-405-4076

COLLEGE PARK, Md. - College Park Academy (CPA), a Prince George’s County public charter school offering a rigorous college preparatory education for students in grades 6 to 12, celebrates the graduation of its first senior class this May.

“We are very proud of this first graduating high school class, and see in their success evidence that this innovative model of education works," said University of Maryland President and Board Chair of the College Park Academy Wallace D. Loh. "Thanks to the combined efforts of political leaders, the community, the university, parents, and the students, this public-charter, blended-learning approach is the future of education."

In addition to an impressive selection of course offerings which includes 13 AP courses and 7 foreign languages, CPA students have the added benefit of access to college-level classes and programs, clubs, and events led by University of Maryland professors and students. Two CPA students are graduating high school a year early, and many are graduating with college credits under their belts.

“It is remarkable to reflect on what our school has been able to accomplish over the past six years,” said Dr. Donna Wisemen, former UMD Dean of Education and a key CPA designer and founding Board member. “We launched CPA with the belief that the school could become a top performer in the state. Since then, we have worked diligently with our education partners to provide our students with access to a world-class, college preparatory education. In turn, they have not only met but far exceeded our expectations. We couldn’t be more proud of our graduating seniors.” CPA’s standardized test scores are now among the highest in Maryland.

The Class of 2019’s 86 students walked the stage at the graduation ceremony on May 29th on the University of Maryland campus. Graduates have been offered admission and scholarships to a wide array of colleges and universities, from the University of Maryland, University of Maryland Baltimore County, and Johns Hopkins, to the University of Chicago and Penn State University.

Founded in 2013 by the College Park City-University Partnership as part of its “Vision 2020” to create a top 20 college town, and in partnership with the University of Maryland, College Park Academy is one of the first "bricks and clicks" middle and high schools in the United States. While CPA students attend school every day, their curriculum is entirely online, and a third  of their courses are taught by online teachers. The online curriculum and instruction, provided by Pearson Connections Education, utilizes personalized, active learning, allowing students to work at their own pace, catch up when they fall behind, and accelerate when they are ready to move ahead.

This school year, CPA received over 1,500 applications for their 200 openings. “Our success has struck a chord with Prince George’s County families, as evidenced by the large waitlist list of applicants,” said Duane Arbogast, former Chief Academic Officer for Prince George’s County and current Interim Executive Director for College Park Academy. “Parents know we provide the kind of schooling which they, and top colleges, want — a focus on rigorous academics, social skills, and respect for others.”

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About the University of Maryland

The University of Maryland, College Park is the state's flagship university and one of the nation's preeminent public research universities. A global leader in research, entrepreneurship and innovation, the university is home to more than 40,000 students, 10,000 faculty and staff, and 280 academic programs. As one of the nation’s top producers of Fulbright scholars, its faculty includes two Nobel laureates, three Pulitzer Prize winners and 57 members of the national academies. The institution has a $1.9 billion operating budget and secures $514 million annually in external research funding. For more information about the University of Maryland, College Park, visit www.umd.edu.

 

Transgenic Fungus Rapidly Killed Malaria Mosquitoes in West African Study

May 30, 2019
Contacts: 

Kimbra Cutlip 301-405-9463, Samantha Watters 301-405-2434

COLLEGE PARK, Md. – A team of scientists from the University of Maryland and Burkina Faso have conducted the first outside-of-a-laboratory trial of a transgenic method for combating malaria. The method, which kills mosquitoes with a fungus genetically engineered to produce spider toxin, is the latest step forward in UMD work to develop powerful new bioinsecticides and biopesticides through the creation of transgenically altered fungi.

In a research paper published on the May 30, 2019 in the journal Science,  the University of Maryland and Burkina Faso scientists describe their successful trial conducted in a screen-enclosed, simulated village setting in Burkina Faso, West Africa. Using a transgenic fungus developed by a UMD team led by Distinguished University Professor of Entomology Raymond St. Leger, mosquito populations were safely reduced in the trial by more than 99 percent.

According to the World Health Organization, malaria affects hundreds of millions of people around the world, killing more than 400,000 annually. Decades of insecticide use has failed to control mosquitoes that carry the malaria parasite and has led to insecticide-resistance among many mosquito strains. For more than a decade, St. Ledger and other scientists have been genetically modifying mosquitoes and other organisms that could help eradicate mosquitoes. However, until now, none of these transgenic approaches had made it beyond laboratory testing.

“No transgenic malaria control has come this far down the road toward actual field testing,” said Brian Lovett, a graduate student in UMD's Department of Entomology who works with St. Leger and is the lead author of the new paper. “This paper marks a big step and sets a precedent for this and other transgenic methods to move forward.”

“We demonstrated that the efficacy of the transgenic fungi is so much better than the wild type that it justifies continued development,” said St. Leger, a co-author of the study.

Next, the international team of scientists hope to test their transgenic fungus in a local village or community. There are many regulatory and social benchmarks to meet before deploying this new method in an open environment such as a village, but the researchers said this study helps make the case for such trials.

Engineering fungi for good

The fungus used by the researchers is a naturally occurring pathogen that infects insects in the wild and kills them slowly. It has been used to control various pests for centuries. The scientists used a strain of the fungus that is specific to mosquitoes and engineered it to produce a toxin that kills mosquitoes more rapidly than they can breed. This transgenic fungus caused mosquito populations in their test site to collapse to unsustainable levels within two generations.

“You can think of the fungus as a hypodermic needle we use to deliver a potent insect-specific toxin into the mosquito,” said St. Leger.

The toxin is an insecticide called Hybrid. It is derived from the venom of the Australian Blue Mountains funnel-web spider and has been approved by the Environmental Protection Agency (EPA) for application directly on crops to control agricultural insect pests.

“Simply applying the transgenic fungus to a sheet that we hung on a wall in our study area caused the mosquito populations to crash within 45 days,” Lovett said. “And it is as effective at killing insecticide-resistant mosquitoes as non-resistant ones.”

Lovett said laboratory tests suggest that the fungus will infect the gamut of malaria-carrying mosquitoes. The abundance of species that transmit malaria has hindered efforts to control the disease, because not all species respond to the same treatment methods.  

To modify the fungus Metarhizium pingshaense so that it would produce and deliver Hybrid, the University of Maryland research team used a standard method that employs a bacterium to intentionally transfer DNA into fungi. The DNA the scientists designed and introduced into the fungi provided the blueprints for making Hybrid along with a control switch that tells the fungus when to make the toxin.

The control switch is a copy of the fungus’ own DNA code. Its normal function is to tell the fungus when to build a defensive shell around itself so that it can hide from an insect’s immune system. Building that shell is costly for the fungus, so it only makes the effort when it detects the proper surroundings—inside the bloodstream of a mosquito.

By combining the genetic code for that switch with the code for making Hybrid, the scientists were able to ensure that their modified fungus only produces the toxin inside the body of a mosquito. They tested their modified fungus on other insects in Maryland and Burkina Faso, and found that the fungus was not harmful to beneficial species such as honeybees.

“These fungi are very selective,” St. Leger said. “They know where they are from chemical signals and the shapes of features on an insect’s body. The strain we are working with likes mosquitoes. When this fungus detects that it is on a mosquito, it penetrates the mosquito’s cuticle and enters the insect. It won’t go to that trouble for other insects, so it’s quite safe for beneficial species such as honeybees.”

After demonstrating the safety of their genetically modified fungus in the lab, Lovett and St. Leger worked closely with scientific colleagues and government authorities in Burkina Faso to test it in a controlled environment that simulated nature. In a rural, malaria-endemic area of Burkina Faso, they constructed a roughly 6,550-square-foot, screened-in structure they called MosquitoSphere. Inside, multiple screened chambers contained experimental huts, plants, small mosquito-breeding pools and a food source for the mosquitoes.

In one set of experiments, the researchers hung a black cotton sheet coated with sesame oil on the wall of a hut in each of three chambers. One sheet received oil mixed with the transgenic fungus Metarhizium pingshaense, one received oil with wild-type Metarhizium and one received only sesame oil. Then, theyreleased 1,000 adult male and 500 adult female mosquitoes into each chamber of MosquitoSphere to establish breeding populations.The researchers then counted mosquitoes in each chamber every day for 45 days.

In the chamber containing the sheet treated with the transgenic fungus, mosquito populations plummeted over 45 days to just 13 adult mosquitoes. That is not enough for the males to create a swarm, which is required for mosquitoes to breed. By comparison, the researchers counted 455 mosquitoes in the chamber treated with wild-type fungus and 1,396 mosquitoes in the chamber treated with plain sesame oil after 45 days. They ran this experiment multiple times with the same dramatic results.

In similar experiments in the lab, the scientists also found that females infected with transgenic fungus laid just 26 eggs, only three of which developed into adults, whereas uninfected females laid 139 eggs that resulted in 74 adults.

According to the researchers, it is critically important that new anti-malarial technologies, such as the one tested in this study, are easy for local communities to employ. Black cotton sheets and sesame oil are relatively inexpensive and readily available locally. The practice also does not require people to change their behavior, because the fungus can be applied in conjunction with pesticides that are commonly used today.  

“By following EPA and World Health Organization protocols very closely, working with the central and local government to meet their criteria and working with local communities to gain acceptance, we’ve broken through a barrier,” Lovett said. “Our results will have broad implications for any project proposing to scale up new, complex and potentially controversial technologies for malaria eradication.”

The research paper, “Transgenic Metarhizium rapidly kills mosquitoes in a malaria-endemic region of Burkina Faso,” Brian Lovett, Etienne Bilgo, Souro Abel Millogo, Abel Kader Ouattarra, Issiaka Sare, Edounou Jacques Gnambani, Roch K. Dabire Abdoulaye Diabate and Raymond J. St. Leger, was published in the journal Science on May 30, 2019.

This work was supported by the National Institutes of Health (Award No RO1-AI106998). The content of this article does not necessarily reflect the views of the organizations. 

Related 2017 release: Mosquito-killing Fungi Engineered with Spider and Scorpion Toxins Could Help Fight Malaria

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