OREGON STATE UNIVERSITY

scientific research and advances

An ancient killer: ancestral malarial organisms traced to age of dinosaurs

CORVALLIS, Ore. – A new analysis of the prehistoric origin of malaria suggests that it evolved in insects at least 100 million years ago, and the first vertebrate hosts of this disease were probably reptiles, which at that time would have included the dinosaurs.

Malaria, a scourge on human society that still kills more than 400,000 people a year, is often thought to be of more modern origin - ranging from 15,000 to 8 million years old, caused primarily by one genus of protozoa, Plasmodium, and spread by anopheline mosquitoes.

But the ancestral forms of this disease used different insect vectors and different malarial strains, and may literally have helped shape animal survival and evolution on Earth, according to George Poinar, Jr., a researcher in the College of Science at Oregon State University.

Poinar suggested in the journal American Entomologist that the origins of this deadly disease, which today can infect animals ranging from humans and other mammals to birds and reptiles, may have begun in an insect such as the biting midge more than 100 million years ago. And in previous work, Poinar and his wife, Roberta, implicated malaria and the evolution of blood-sucking insects as disease vectors that could have played a significant role in the extinction of the dinosaurs.

“Scientists have argued and disagreed for a long time about how malaria evolved and how old it is,” Poinar said. “I think the fossil evidence shows that modern malaria vectored by mosquitoes is at least 20 million years old, and earlier forms of the disease, carried by biting midges, are at least 100 million years old and probably much older.”

Since the sexual reproduction stage of malaria only occurs in insects, Poinar said in the new study that they must be considered the primary hosts of the disease, not the vertebrate animals that they infect with disease-causing protozoa. And he believes the evidence points toward the Gregarinida as a protozoan parasite group that could have been the progenitors of malaria, since they readily infect the insects that vector malaria today.

Understanding the ancient history of malaria evolution, Poinar said, might offer clues to how its modern-day life cycle works, how it evolved, and what might make possible targets to interrupt its transmission through its most common vector, the Anopheles mosquito.

Understanding the evolution of malaria also takes one on a worldwide journey, according to evidence found in insects preserved in amber. Poinar is an international expert in using plant and animal life forms preserved in this semi-precious stone to help learn more about the biology and ecology of the distant past.

Poinar was the first to discover a type of malaria in a 15-20 million-year-old fossil from the New World, in what is now the Dominican Republic. It was the first fossil record of Plasmodium malaria, one type of which is now the strain that infects and kills humans.

Even further back, malaria may have been one of the diseases that arose, along with the evolution of insects, and had a huge impact on animal evolution. In a 2007 book, “What Bugged the Dinosaurs? Insects, Disease and Death in the Cretaceous,” George and Roberta Poinar argued that insects carried diseases that contributed to the widespread extinction of the dinosaurs around the “K-T boundary” about 65 million years ago.

“There were catastrophic events known to have happened around that time, such as asteroid impacts and lava flows,” Poinar said. “But it’s still clear that dinosaurs declined and slowly became extinct over thousands of years, which suggests other issues must also have been at work. Insects, microbial pathogens and vertebrate diseases were just emerging around that same time, including malaria.”

Avian malaria has been implicated in the extinction of many bird species in Hawaii just in recent decades, especially in species with no natural resistance to the disease. Different forms of malaria, which is now known to be an ancient disease, may have been at work many millions of years ago and probably had other implications affecting the outcome of vertebrate survival, Poinar said.

The first human recording of malaria was in China in 2,700 B.C., and some researchers say it may have helped lead to the fall of the Roman Empire. In 2015 there were 214 million cases worldwide, according to the World Health Organization. Immunity does not occur naturally and the search for a vaccine has not yet been achieved.

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Biting midge


Biting midge
with ancestral malaria


Oldest fossil showing Plasmodium malaria
Oldest fossil with
Plasmodium malaria

U.S. adults get failing grade in healthy lifestyle behavior

CORVALLIS, Ore. – Only 2.7 percent of the U.S. adult population achieves all four of some basic behavioral characteristics that researchers say would constitute a “healthy lifestyle” and help protect against cardiovascular disease, a recent study concluded.

In this study, researchers from Oregon State University and the University of Mississippi examined how many adults succeed in four general barometers that could help define healthy behavior: a good diet, moderate exercise, a recommended body fat percentage and being a non-smoker. It’s the basic health advice, in other words, that doctors often give to millions of patients all over the world.

Such characteristics are associated with a lower risk of cardiovascular disease as well as many other health problems, such as cancer and type 2 diabetes.

“The behavior standards we were measuring for were pretty reasonable, not super high,” said Ellen Smit, senior author on the study and an associate professor in the OSU College of Public Health and Human Sciences. “We weren’t looking for marathon runners.”

From the perspective of public health, the findings of the research were not encouraging, Smit said.

“This is pretty low, to have so few people maintaining what we would consider a healthy lifestyle,” she said. “This is sort of mind boggling. There’s clearly a lot of room for improvement.”

Part of the value of this study, the researchers said, is that the results are based on a large study group, 4,745 people from the National Health and Nutrition Examination Survey. It also included several measured behaviors, rather than just relying on self-reported information.

Measurements of activity were done with an accelerometer, a device people wore to determine their actual level of movement, with a goal of 150 minutes of moderate-to-vigorous activity a week. Blood samples were done to verify a person was a non-smoker. Body fat was measured with sophisticated X-ray absorptiometry, not just a crude measurement based on weight and height. A healthy diet was defined in this study as being in about the top 40 percent of people who ate foods recommended by the USDA.

The lifestyle characteristics were then compared to “biomarkers” of cardiovascular health. Some are familiar, such as blood pressure, cholesterol and glucose levels. Others are more sophisticated, such as C-reactive protein, fasting triglycerides, homocysteine and other data that can provide evidence of cardiovascular risk.

Many people, of course, accomplished one or more of the four basic lifestyle goals, such as not smoking or being adequately active. The most striking finding was how few people accomplished all the goals.

“I would expect that the more healthy lifestyles you have, the better your cardiovascular biomarkers will look,” Smit said.

Indeed, the researchers found that having three or four healthy lifestyles, compared to none, generally was associated with better cardiovascular risk biomarkers, such as lower serum cholesterol and homocysteine levels.  Having at least one or two healthy lifestyle characteristics, compared to none, was also associated with better levels of some cardiovascular risk biomarkers.

Among the other findings of the research:

  • Although having more than one healthy lifestyle behavior is important, specific health characteristics may be most important for particular cardiovascular disease risk factors.
  • For healthy levels of HDL and total cholesterol, the strongest correlation was with normal body fat percentage.
  • A total of 71 percent of adults did not smoke, 38 percent ate a healthy diet, 10 percent had a normal body fat percentage, and 46 percent were sufficiently active.
  • Only 2.7 percent of all adults had all four healthy lifestyle characteristics, while16 percent had three, 37 percent had two, 34 percent had one, and 11 percent had none.
  • Women were more likely to not smoke and eat a healthy diet, but less likely to be sufficiently active.
  • Mexican American adults were more likely to eat a healthy diet than non-Hispanic white or black adults.
  • Adults 60 years and older had fewer healthy characteristics than adults ages 20-39, yet were more likely to not smoke and consume a healthy diet, and less likely to be sufficiently active.

More research is needed, experts say, to identify ways to increase the adoption of multiple healthy lifestyle characteristics among adults.

This study was published in the Mayo Clinic Proceedings and was done in collaboration with researchers from the University of Mississippi and the University of Tennessee-Chattanooga. The lead author was Paul Loprinzi, who graduated from OSU and who’s now at the University of Mississippi.

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Ellen Smit, 541-737-3833

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Ellen Smit, Ph.D., RD

Ellen Smit

Wetland enhancement in Midwest could help reduce catastrophic floods of the future

CORVALLIS, Ore. – According to a new study from Oregon State University, restoration of wetlands in the Midwest has the potential to significantly reduce peak river flows during floods - not only now, but also in the future if heavy rains continue to increase in intensity.

Wetland restoration could also provide a small step toward a hydrologic regime in this region that more closely resembles its historic nature, before roads and cities were constructed, forests were lost, and millions of acres tile-drained to increase agricultural production.

An evaluation of potential wetlands in one watershed in central Indiana found that if just 1.5 percent of the land were used for wetlands, the peak flow of the overall watershed could be reduced by up to 17.5 percent. Also of importance, researchers said, is that expansion of wetlands appears to provide significant benefits across a wide range of possible climate scenarios.

The study was published in Ecological Engineering, in work supported by the National Science Foundation and the National Oceanic and Atmospheric Administration.

“Flood management in the Midwest is now almost entirely concentrated on use of dams and levees,” said Meghna Babbar-Sebens, an assistant professor of civil engineering in the College of Engineering, and the Eric H.I. and Janice Hoffman Faculty Scholar at OSU.

“Wetland construction or restoration could provide a natural and ecological option to help with flood concerns, and serve as an additional tool for flood management. Greater investments in this approach, or similar approaches that increase storage of water in the upper landscape of a watershed, should be seriously considered.”

The new research considered not just the problem now – which is serious – but what the future may bring.

The study used climate models supported by the North American Regional Climate Change Assessment Program, along with a hydrology model to examine the impact of wetlands during the climate scenarios for a mid-century period from 2041 to 2070. It suggests this central Indiana region could see continued increases in extreme events, such as more extremely hot days during summer and more heavy rain in the wettest 5-day periods.

“There’s some variation in the models, but there’s general agreement that the future will bring more heavy precipitation events,” Babbar-Sebens said. “How we transfer and store runoff on the landscape is going to become even more critical.”

“From the perspective of a decision maker, an advantage of wetland construction is that it would significantly reduce flooding from heavy precipitation in almost every possible scenario. Wetlands are consistently effective.”

An obstacle at this point, she said, is that many incentive programs that support wetland restoration and creation usually focus on ecology, wildlife enhancement and water quality issues – and there are limited funding mechanisms to create upland wetlands for flood management. This limits the economic incentives for farmers and landowners to set aside room for wetlands, especially with the high price of agricultural crops.

New financial models and flood management policies would probably be needed to address this, Babbar-Sebens said.

Deforestation, agriculture and the historic growth of cities with impervious infrastructure have hugely changed the face of the Midwest and its hydrology, leading to frequent floods.

Climate change is now exacerbating that problem. In 2011, Indiana experienced record-breaking heat in seven counties, record-breaking rainfall in 22 counties, and record-breaking snowfall in six counties. The state has been declared a flood disaster area 14 times between 2000 and 2011, compared to only four times in the decade prior to that.

The great Mississippi River flood of 2011 was considered a “500-year event” and caused $2.8 billion in damage. It flooded more than 21,000 homes and businesses and 1.2 million acres of agricultural land, according to a report from the U.S. Army Corps of Engineers.

Wetlands help reduce some of these flooding problems by storing water away from stream channels and releasing it more slowly, while also improving water quality and providing wildlife habitat. Other studies have shown that wetland construction in the Mississippi-Ohio-Missouri river basins could also significantly reduce nitrogen loads in the rivers, which has led to an enormous “dead zone” in the Gulf of Mexico.

A methodology for evaluating wetlands with respect to historic climate and future climate scenarios, created in this research, should be applicable to other watersheds in the Midwest, researchers said.

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Meghna Babbar-Sebens, 541-737-8536

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Wetlands
River wetlands

Southern right whales slowly rebounding, but still decades away from full recovery

NEWPORT, Ore. – A new study has determined that right whales in the Southern Hemisphere were once more abundant than previously thought, making their full recovery from near-extinction another 50 to 100 years away.

An international team of scientists using a combination of catch records from 19th-century logbooks and modern computer modeling techniques concluded that as many as 40,000 right whales once inhabited the waters near New Zealand before whaling drove them to the brink of extinction. As few as 20 mature females were estimated to have survived into the beginning of the 20th century.

Results of the study are being published this week in the journal Royal Society Open Science.

“This is the first time we have been able to estimate the pre-whaling abundance for this population of right whales before they were nearly decimated,” said Scott Baker, associate director of the Marine Mammal Institute at Oregon State University, and co-author on the study. “Only a handful of whales survived, and those were threatened again in the 1960s by illegal Soviet whaling.

“The waters around New Zealand have been depleted of right whales for nearly 200 years,” added Baker, who works out of OSU’s Hatfield Marine Science Center in Newport, Ore. “We have little idea of the ecological role they played prior to whaling, or how they may contribute to ecosystems changes as their population slowly recovers.”

Baker and co-author Nathalie Patenaude initiated the decade-long study of the remnant New Zealand right whale population in 1995, in part because the region has one of the best historical catch records from whaling logbooks and other sources. Southern right whales were particularly vulnerable to exploitation because they are slow swimmers with strong fidelity to sheltered bays for calving, making them “predictable and easy targets,” the authors note.

The term “right whale” was coined because they were so easy to hunt.

“Once we had a good idea about the likely range of catches, we could do a full reconstruction using current estimates of abundance and population increase to measure the population’s trajectory through time and how large it was,” said Jennifer Jackson, lead author on the paper. Jackson, a former post-doctoral fellow with Baker at Oregon State, is now with the British Antarctic Survey.

The researchers’ analysis concluded that prior to whaling right whales were abundant in New Zealand waters, numbering about 28,000 to 33,000 individuals. If most of the right whales harvested in the southwest Pacific Ocean were New Zealand whales, the population rises to 47,000 whales.

“Put in context, the estimated size of the current New Zealand population is less than 12 percent of these numbers,” Jackson said.

Catch records of whaling from the early 19th-century were patchy and required a bit of detective work, said Emma Carroll of St. Andrews University, also a co-author on the study.

“We went back through early colonial New Zealand historical records and whaling logbooks, and even had to cross-reference what ships had been seen where to get an understanding of the scale of operations during the winter in New Zealand,” Carroll said.

Funding for the study was provided by the Royal Society of New Zealand, The Lenfest Ocean Program of the Pew Charitable Trust, Oregon State University’s general research fund, and the New Zealand National Institute of Water and Atmospheric Research (NIWA).

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Scott Baker, scott.baker@oregonstate.edu; 541-867-0255

PNAS Study: Carbon from land played a role during last deglaciation

CORVALLIS, Ore. – As the Earth emerged from its last ice age several thousand years ago, atmospheric carbon dioxide increased and further warmed the planet. Scientists have long speculated that the primary source of this CO2 was from the deep ocean around Antarctica, though it has been difficult to prove.

A new study being published this week in Proceedings of the National Academy of Sciences confirmed that the ocean played a significant role in the rise of atmospheric carbon dioxide, but also documents the signature of land-based carbon sources in Antarctic ice cores that contributed to abrupt increases in CO2.

“There wasn’t a steady rate of rising carbon dioxide during the last deglaciation,” said Edward Brook, an Oregon State University paleoclimatologist and co-author on the PNAS study. “It happened in fits and starts. With the new precise techniques we developed to fingerprint the sources, it is apparent that the early carbon largely came from the ocean, but we think the system got a jolt from an influx of land-based carbon a few times as the climate warmed.”

The study was funded by the National Science Foundation with support from the Marsden Fund Council in New Zealand.

The breakthrough came from the comparison of carbon isotope ratios in pristine samples of ice mined from the Taylor Glacier in Antarctica. Although such isotopic fingerprinting strategies have been attempted before, the key was detailed work both in the field and in the laboratory that improved the precision to read the record in fine detail.

The study found that during the initial rise in atmospheric CO2 – from 17,600 years ago to 15,500 years ago – the light isotope 12-C increased faster than the heavier isotopes, pointing to a release of carbon from the deep ocean. However, at about 16,300 years ago and 12,900 years ago, there were abrupt, century-scale perturbations in the carbon ratio that suggested rapid release of carbon from land sources such as plants and soils.

Although the region of the CO2 source is not clear, the scientists say, at least one of the two events may come from the tropics because methane from tropical swamps rose at the same time.

“One theory,” Brook said, “is that an influx of icebergs in the Northern Hemisphere at about 16,300 years ago – from retreating ice sheets – cooled the North Atlantic Ocean and pushed the tropical rain belt southward over Brazil, expanding the wetlands. Swamps in the Southern Hemisphere, in places like Brazil, may have become wetter and produced methane, while plants and soils in the Northern Hemisphere, in places like China, may have been hit by drought and produced CO2.”

During the next 4,000 years, the continued rise of atmospheric CO2 – by about 40 parts per million – was marked by small changes in the carbon-13 to carbon-12 ratio indicating additional sources of carbon from rising ocean temperatures. This CO2 source, analogous to the bubbles released from warming soda pop, may have added to the biological carbon sources.

The application of this carbon isotope technique became possible because of a unique site along the margin of the Antarctic ice sheet where old ice that flowed from the interior is exposed at the surface of a large glacier – Taylor Glacier – named for a geologist on an early expedition to the frozen continent. Ice that normally would be a mile or more below the surface is available to easily sample in large quantities.

These large samples, laboriously cut from the exposed ice layers, allowed the precise measurements, the  researchers report.

“The isotope ratio technique gives us a sort of ‘return address’ for carbon dioxide,” noted Thomas Bauska, a former Ph.D. student and post-doctoral researcher in OSU’s College of Earth, Ocean, and Atmospheric Sciences, who was lead author on the PNAS study.  “The technique is new, extremely precise and gives us one of the best windows into the Earth’s past climate.”

Bauska is now a post-doctoral researcher at the University of Cambridge in England.

That window into the past may provide hints at what may happen in the future under a new global warming regime, noted Alan Mix, an Oregon State oceanographer and co-author on the study. However, he cautioned, it isn’t always simple to predict the future based on past events.

“The rise of CO2 is a complicated beast, with different behaviors triggered at different times,” Mix said. “Although the natural changes at the end of the ice age are not a direct analogy for the future, the rapid changes do provide a cautionary tale. Manmade warming from CO2 pollution may trigger further release from ‘natural sources,’ and this could exacerbate greenhouse gases and warming.”

Other authors on the PNAS study include Daniel Baggenstos and Jeffrey Severinghaus, Scripps Institution of Oceanography; Shaun Marcott, University of Wisconsin-Madison; Vasillii Petrenko, University of Rochester; Hinrich Schaefer, National Institute of Water and Atmospheric Research in New Zealand; and James Lee, Oregon State University.

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Ed Brook, 541-737-8197, brook@geo.oregonstate.edu;

Thomas Bauska, +44 1223 764917, tkb28@cam.ac.uk;

Alan Mix, 541-737-5212, amix@coas.oregonstate.edu

Five years after tsunami, scientists cross fingers on invasive species establishment

CORVALLIS, Ore. – Five years after a massive earthquake struck Japan and triggered a tsunami that is still washing debris onto the West Coast of the United States, scientists are unsure whether any of the 200-plus non-native species that hitchhiked over on that debris have gained a foothold in Northwest waters.

Four separate findings of barred knifejaws (Oplegnathus fasciatus) – a fish native to Japan – have been reported over the past three years, and Mediterranean blue mussels have been ubiquitous on tsunami debris. Yet no populations of non-native species that arrived with the tsunami debris are known to have established reproductive populations.

“Maybe we dodged the bullet, although it is still too early to tell,” said John Chapman, an Oregon State University invasive species expert who has investigated tsunami debris along the Pacific coastline. “It is possible that we have not yet discovered these reproductive populations, or that some species from Japan may be cross-breeding with our own species.”

Scientists have not had adequate resources to look extensively up and down the Pacific coast for evidence of establishment by non-native species – especially along long stretches of rugged shoreline.

The magnitude-9 earthquake that struck Japan on March 11, 2011, was the largest in that country’s history and generated a tsunami that had waves estimated as high as 133 feet. The power of these two events, combined with the growth of human settlement over the past two to three centuries, created a new paradigm, said Samuel Chan, an expert in aquatic ecosystem health and invasive species with the Oregon Sea Grant program at Oregon State.

“A tsunami 300 years ago, or even just 60 years ago, would not have created as much marine debris that became a vehicle for moving species across the Pacific Ocean that could become invasive,” Chan said. “What makes these major tsunami-driven events different in modern times is the substantial human industrial infrastructure that we have built along the Pacific coast.”

The first indication that a potential problem loomed came in June of 2012, when a large concrete dock that originated in Misawa, Japan, washed ashore near Newport, Oregon – just a stone’s throw from OSU’s Hatfield Marine Science Center.

The 165-ton dock – which was 66 feet long, 19 feet wide and seven feet high – was covered with nearly 200 species of plant and animal life, including a species of brown algae (Undaria pinnatifida) that nearly covered the structure. Chapman and colleague Jessica Miller also found Northern Pacific sea stars, Japanese shore crabs, at least eight species of mollusk, an anemone, a sponge, an oyster, a solitary tunicate, three or more species of amphipods, four or more species of barnacles and worms, bryozoans, a European blue mussel known as Mytilus galloprovincialis, and a sea urchin.

“Frankly,” Chapman said, “we were blown away. We had always thought these organisms would not be able to survive the long trip across the Pacific Ocean, the middle of which is a biological desert. Yet here they were.”

In March of 2013, a boat from Japan containing five barred knifejaws washed ashore in the state of Washington; one is still on display in the Seaside Aquarium. A second knifejaw was filmed in a shipwreck near Monterey, California. Then a third knifejaw was found trapped in a crab pot near Port Orford, Oregon, in February 2015. Just two months later, another was discovered in a boat tank from Japanese tsunami debris near Seal Rock, Oregon.

“Those knifejaws all survived,” Chapman said. “Theoretically, the water temperatures north of Point Conception, California, are too cold for them to spawn. But it’s hard to know for sure.”

Chan has been working with colleagues from Japan’s Tottori University for Environmental Studies on a project that launched dozens of transponders into the waters off that country and traced their path across the Pacific Ocean to North America. The researchers’ goal is to find out what routes the tsunami debris might have taken and how that may influence the type of organisms found aboard the debris.

“Some species have been discovered that are not native to Japan, and others have not even been identified,” Chan noted. “The transponders bobbed around off Japan for some time and then went fairly quickly across the Pacific. But once they arrived here, they moved in and out of near-shore waters, and up and down the coast.

“Satellite tracking of transponders and their discovery by beachcombers indicates that they floated for 2-3 years before they beached on land,” Chan added. “The movement patterns of the transponders within the continental shelves of Japan and North American – where nutrients and food are relatively available – could be one piece of a complex puzzle that have allowed these organisms to survive the trans-Pacific journey.”

Chan said international exchanges in the five years since the Tohoku earthquake and tsunami have been a bright point, resulting in close collaboration and a shared sense of discovery among Japanese and American scientists.

“The debris still arriving five years later is a reminder that has raised awareness among people – many of whom have been complacent or unaware – about the power and destruction that earthquakes and tsunamis can cause on both sides of the Pacific,” Chan said.

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Sam Chan, 541-737-1583, Samuel.chan@oregonstate.edu;

John Chapman, 541-867-0235, john.chapman@oregonstate.edu

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(Left: OSU's John Chapman examines a mussel-encrusted boat from Japan.)

 

 

Natural Resources Leadership Academy 2012

Sam Chan informs coastal visitors about the Japanese dock (background) that washed ashore from Japan.

 

knifejaws

A barred knifejaw from Japan survived its trans-Pacific Ocean journey.

 

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OSU's Jessica Miller examines a sea star.

OSU joins center to enhance teaching skills of STEM graduate students

CORVALLIS, Ore. – Oregon State University has become one of 46 members of the Center for the Integration of Research, Teaching and Learning, or CIRTL, an initiative to increase the diversity and enhance the teaching skills of graduate students in the fields of science, technology, engineering and math (STEM).

Eighty percent of the nation’s doctoral degrees in these fields come from only 100 research universities, allowing CIRTL to target those universities to provide better teaching and mentoring techniques for STEM graduate students.

As a new member of this center, OSU will develop programs focused on teaching-as-research, learning communities and learning through diversity. This will include developing new courses, hosting events, offering internship opportunities and collaborating with other CIRTL-affiliated universities.

“OSU already has some great momentum toward graduate student and post-doc teaching development through our campus-wide fall orientation, and our graduate certificate in college and university teaching,” said Jessica White, OSU co-leader for this initiative.

“Being a CIRTL member indicates that OSU is committed to supporting GTAs in their current duties, and in developing future STEM faculty in additional ways that are sustainable and flexible for all of those involved.”

Researchers say that ineffective teaching is often a reason students leave STEM programs. One issue is that graduate students are often focused on research, and have little preparation to be teachers. CIRTL programs work to change that.

Nearly 4,500 graduate students are currently enrolled at OSU. Of those, more than 1,000 are on graduate teaching assistantships each term, and together have about 30,000 undergraduate student contacts each week.

“This is a sizeable number, so our GTAs have a considerable impact on the quality of undergraduate education,” White said. “It’s imperative that we adequately prepare them for their current institutional appointments, and that we prepare them for their future career pursuits.”

Brittany Robertson, a GTA pursuing her Ph.D. at the School of Nuclear Science and Engineering at Oregon State, said the biggest challenge of teaching as a graduate student is fulfilling her other obligations as a student and researcher.

“We often end up teaching freshmen who are very used to high school, and college is a different environment,” Robertson said. “There are often frustrations associated with students coping with and adjusting to the different set of expectations associated with the higher education environment. New programs helping us as GTAs develop our teaching skills and teaching styles to assist students in making this transition would be very helpful.”

CIRTL operates from within the Wisconsin Center for Education Research in UW-Madison’s School of Education.  OSU was one of 25 universities to be added this year.

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Jessica White, 541-737-8576; Jessica.white@oregonstate.edu

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Brittany Robertson

Mariana Trench: Seven miles deep, the ocean is still a noisy place

NEWPORT, Ore. – For what may be the first time, scientists have eavesdropped on the deepest part of the world’s oceans and instead of finding a sea of silence, they discovered a cacophony of sounds both natural and caused by humans.

For three weeks, a titanium-encased hydrophone recorded ambient noise from the ocean floor at a depth of more than 36,000 feet in a trough known as Challenger Deep in the fabled Mariana Trench near Micronesia. The team of researchers from the National Oceanic and Atmospheric Administration, Oregon State University and the U.S. Coast Guard expected to hear little. They were surprised.

“You would think that the deepest part of the ocean would be one of the quietest places on Earth,” said Robert Dziak, a NOAA research oceanographer and chief scientist on the project. “Yet there really is almost constant noise from both natural and man-made sources. The ambient sound field at Challenger Deep is dominated by the sound of earthquakes, both near and far was well as the distinct moans of baleen whales and the overwhelming clamor of a category 4 typhoon that just happened to pass overhead.

“There was also a lot of noise from ship traffic, identifiable by the clear sound pattern the ship propellers make when they pass by,” added Dziak, who has a courtesy appointment in Oregon State’s College of Earth, Ocean, and Atmospheric Sciences. “Guam is very close to Challenger Deep and is a regional hub for container shipping with China and The Philippines.”

The project, which was funded by the NOAA Office of Ocean Exploration and Research, was designed to establish a baseline for ambient noise in the deepest part of the Pacific Ocean. Anthropogenic, or human-caused noise has increased steadily over the past several decades and getting these first recordings will allow scientists in the future to determine if the noise levels are growing.

Getting those first sounds wasn’t easy.

The bottom of the Challenger Deep trough is roughly seven miles below the ocean’s surface. In fact, you could put the world’s tallest peak – Mount Everest – in the trench and its top would still be more than a mile from the surface.

The pressure at that depth is incredible, said Haru Matsumoto, an Oregon State ocean engineer who along with NOAA engineer Chris Meinig helped to develop a hydrophone capable of withstanding such pressure. In the average person’s home or office, the atmospheric pressure is about 14.7 pounds per square inch; at the bottom of the Mariana Trench, it is more than 16,000 PSI.

“We had never put a hydrophone deeper than a mile or so below the surface, so putting an instrument down some seven miles into the ocean was daunting,” Matsumoto said. “We had to drop the hydrophone mooring down through the water column at no more than about five meters per second. Structures don’t like rapid change and we were afraid we would crack the ceramic housing outside the hydrophone.”

Partnering with the U.S. Coast Guard, the researchers deployed the hydrophone from the Guam-based cutter Sequoia in July 2015. It took more than six hours for the instrument package to free-fall to the bottom of the Mariana Trench. Its recordings filled the flash drive in about 23 days, but the researchers had to wait until November to retrieve the hydrophone because of ships’ schedules and persistent typhoons.

Once back on site, they recovered the hydrophone mooring by sending an acoustic signal from the ship above, triggering its release from the seafloor. Attached floats allowed it to gradually ascend to the surface.

“It is akin to sending a deep-space probe to the outer solar system,” Dziak said. “We’re sending out a deep-ocean probe to the unknown reaches of inner space.”

For the past several months, Dziak and his colleagues have been analyzing the sounds and differentiating natural sounds from ships and other human activities.

“We recorded a loud magnitude 5.0 earthquake that took place at a depth of about 10 kilometers (or more than six miles) in the nearby ocean crust,” Dziak said. “Since our hydrophone was at 11 kilometers, it actually was below the earthquake, which is really an unusual experience. The sound of the typhoon was also dramatic, although the cacophony from big storms tends to be spread out and elevates the overall noise for a period of days.”

Matsumoto said the hydrophone also picked up a lot of noise from the surface of the ocean – some seven miles above – including waves and winds disturbing the surface.

“Sound doesn’t get as weak as you think it does even that far from the source,” he said.

Another OSU co-investigator on the project, Joe Haxel, will lead a planned return to Challenger Deep in 2017, where the researchers will deploy the hydrophone for a longer period of time and attach a deep-ocean camera.

Dziak, Matsumoto and Haxel are affiliated with the Acoustics Program in the NOAA/Pacific Marine Environmental Laboratory and work at OSU’s Hatfield Marine Science Center in Newport, Ore. The project in Challenger Deep is one of a number of projects in which the U.S. Coast Guard partners with NOAA to sponsor scientific research.

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Bob Dziak, 541-867-0175, Robert.P.Dziak@noaa.gov;

Haru Matsumoto, 541-867-0272; haru.matsumoto@oregonstate.edu

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DNA evidence shows that salmon hatcheries cause substantial, rapid genetic changes

CORVALLIS, Ore. – A new study on steelhead trout in Oregon offers genetic evidence that wild and hatchery fish are different at the DNA level, and that they can become different with surprising speed.

The research, published today in Nature Communications, found that after one generation of hatchery culture, the offspring of wild fish and first-generation hatchery fish differed in the activity of more than 700 genes.

A single generation of adaptation to the hatchery resulted in observable changes at the DNA level that were passed on to offspring, scientists reported.

This research was conducted at Oregon State University in collaboration with the Oregon Department of Fisheries and Wildlife. Scientists say the findings essentially close the case on whether or not wild and hatchery fish can be genetically different.

Differences in survival and reproductive success between hatchery and wild fish have long offered evidence of rapid adaptation to the hatchery environment. This new DNA evidence directly measured the activity of all genes in the offspring of hatchery and wild fish. It conclusively demonstrates that the genetic differences between hatchery and wild fish are large in scale and fully heritable.

“A fish hatchery is a very artificial environment that causes strong natural selection pressures,” said Michael Blouin, a professor of integrative biology in the OSU College of Science. “A concrete box with 50,000 other fish all crowded together and fed pellet food is clearly a lot different than an open stream.”

It’s not clear exactly what traits are being selected for, but the study was able to identify some genetic changes that may explain how the fish are responding to the novel environment in the hatchery.

“We observed that a large number of genes were involved in pathways related to wound healing, immunity, and metabolism, and this is consistent with the idea that the earliest stages of domestication may involve adapting to highly crowded conditions,” said Mark Christie, lead author of the study.

Aside from crowding, which is common in the hatchery, injuries also happen more often and disease can be more prevalent.

The genetic changes are substantial and rapid, the study found. It’s literally a process of evolution at work, but in this case it does not take multiple generations or long periods of time.

“We expected hatcheries to have a genetic impact,” Blouin said. “However, the large amount of change we observed at the DNA level was really amazing. This was a surprising result.”

With the question put to rest of whether hatchery fish are different, Blouin said, it may now be possible to determine exactly how they are different, and work to address that problem. When the genetic changes that occur in a hatchery environment are better understood, it could be possible to change the way fish are raised in order to produce hatchery fish that are more like wild fish. This research is a first step in that direction.

This work was performed using steelhead trout from the Hood River in Oregon. It was supported by the Bonneville Power Administration and the Oregon Department of Fish and Wildlife.

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Michael Blouin, 541-737-2362

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Juvenile steelhead trout
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Nutrient slowed cancer cell growth in early-stage breast cancer

CORVALLIS, Ore. – One of the first clinical studies to look at the effect of sulforaphane on breast tissues of women diagnosed with breast cancer showed that this compound was well tolerated and slowed the growth of cancer cells, especially at early stages.

Sulforaphane is a compound found in broccoli and many other cruciferous vegetables, and it has long shown evidence of value in cancer prevention, researchers say.

This new research suggests it may ultimately play a role in slowing cancer growth as well – along with other proven approaches such as surgery, radiation and chemotherapy.

The findings were published in the journal Cancer Prevention Research by scientists from Oregon State University and the Oregon Health & Science University.

“Our original goal was to determine if sulforaphane supplements would be well tolerated and might alter some of the epigenetic mechanisms involved in cancer,” said Emily Ho, a professor in the OSU College of Public Health and Human Sciences. 

“We were surprised to see a decrease in markers of cell growth, which means these compounds may help slow cancer cell growth,” said Ho, a co-author on the study. “This is very encouraging. Dietary approaches have traditionally been thought to be limited to cancer prevention, but this demonstrated it could help slow the growth of existing tumors.”

When better understood and studied, it’s possible that sulforaphane or other dietary compounds may be added to traditional approaches to cancer therapy, whether to prevent cancer, slow its progression, treat it or stop its recurrence, said Ho, who is also the endowed director of the Moore Family Center for Whole Grain Foods, Nutrition and Preventive Health, and a principal investigator with OSU’s Linus Pauling Institute.

This research was done with 54 women with abnormal mammograms who were scheduled for a breast biopsy and were studied in a double-blind, randomized, placebo-controlled trial. They received either a placebo or supplements that provided sulforaphane. The amount of sulforaphane they received would equate to about one cup of broccoli sprouts per day, if eaten as a food.

A number of studies in the past have found that women with a high intake of cruciferous vegetables – such as broccoli, cauliflower, cabbage or kale – have a decreased risk of breast cancer. Research has also shown that sulforaphane, which is found at the highest levels in such foods, can modulate breast cancer risk at several stages of carcinogenesis and through different mechanisms.

In particular, sulforaphane appears to inhibit histone deacetylases, or HDACs, which in turn enhances the expression of tumor suppressor genes that are often silenced in cancer cells.

The intake of sulforaphane in this study did, in fact, reduce HDAC activity, as well as cancer cell growth.

Additional studies are needed to evaluate dose responses, work with larger populations, and examine the responses of other relevant molecular targets to either foods or supplements containing sulforaphane, researchers said. Some other studies have also suggested that different types of broccoli extract preparations may be more bioavailable for uses of this type.

This research was supported by the National Cancer Institute, the National Institutes of Health, and the National Institute of Environmental Health Sciences.

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Emily Ho, 541-737-9559

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