OREGON STATE UNIVERSITY

scientific research and advances

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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OSU student

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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A link to sound files, images and a video can be found at: http://bit.ly/1QSb8Mv

 

 

Deep trench

 

ChallengerDeep

 

CD-hydrophone-close

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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Steelhead


Steelhead trout


Juvenile steelhead trout
Juvenile steelhead

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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Broccoli sprouts
Broccoli sprouts

Scientists say window to reduce carbon emissions is small

CORVALLIS, Ore. – At the rate humans are emitting carbon into the atmosphere, the Earth may suffer irreparable damage that could last tens of thousands of years, according to a new analysis published this week.

Too much of the climate change policy debate has focused on observations of the past 150 years and their impact on global warming and sea level rise by the end of this century, the authors say. Instead, policy-makers and the public should also be considering the longer-term impacts of climate change.

“Much of the carbon we are putting in the air from burning fossil fuels will stay there for thousands of years – and some of it will be there for more than 100,000 years,” said Peter Clark, an Oregon State University paleoclimatologist and lead author on the article. “People need to understand that the effects of climate change on the planet won’t go away, at least not for thousands of generations.”

The researchers’ analysis is being published this week in the journal Nature Climate Change.

Thomas Stocker of the University of Bern in Switzerland, who is past-co-chair of the IPCC’s Working Group I, said the focus on climate change at the end of the 21st century needs to be shifted toward a much longer-term perspective.

“Our greenhouse gas emissions today produce climate-change commitments for many centuries to millennia,” said Stocker, a climate modeler and co-author on the Nature Climate Change article. “It is high time that this essential irreversibility is placed into the focus of policy-makers.

“The long-term view sends the chilling message (about) what the real risks and consequences are of the fossil fuel era,” Stocker added. “It will commit us to massive adaptation efforts so that for many, dislocation and migration becomes the only option.”

Sea level rise is one of the most compelling impacts of global warming, yet its effects are just starting to be seen. The latest IPCC report, for example, calls for sea level rise of just one meter by the year 2100. In their analysis, however, the authors look at four difference sea level-rise scenarios based on different rates of warming, from a low end that could only be reached with massive efforts to eliminate fossil fuel use over the next few decades, to a higher rate based on the consumption of half the remaining fossil fuels over the next few centuries.

With just two degrees (Celsius) warming in the low-end scenario, sea levels are predicted to eventually rise by about 25 meters. With seven degrees warming at the high-end scenario, the rise is estimated at 50 meters, although over a period of several centuries to millennia.

“It takes sea level rise a very long time to react – on the order of centuries,” Clark said. “It’s like heating a pot of water on the stove; it doesn’t boil for quite a while after the heat is turned on – but then it will continue to boil as long as the heat persists. Once carbon is in the atmosphere, it will stay there for tens or hundreds of thousands of years, and the warming, as well as the higher seas, will remain.”

Clark said for the low-end scenario, an estimated 122 countries have at least 10 percent of their population in areas that will be directly affected by rising sea levels, and that some 1.3 billion – or 20 percent of the global population – live on lands that may be directly affected. The impacts become greater as the warming and sea level rise increases.

“We can’t keep building seawalls that are 25 meters high,” noted Clark, a professor in OSU’s College of Earth, Ocean, and Atmospheric Sciences. “Entire populations of cities will eventually have to move.”

Daniel Schrag, the Sturgis Hooper Professor of Geology at Harvard University, said there are moral questions about “what kind of environment we are passing along to future generations.”

“Sea level rise may not seem like such a big deal today, but we are making choices that will affect our grandchildren’s grandchildren – and beyond,” said Schrag, a co-author on the analysis and director of Harvard’s Center for the Environment. “We need to think carefully about the long time-scales of what we are unleashing.”

The new paper makes the fundamental point that considering the long time scales of the carbon cycle and of climate change means that reducing emissions slightly or even significantly is not sufficient. “To spare future generations from the worst impacts of climate change, the target must be zero – or even negative carbon emissions – as soon as possible,” Clark said.

“Taking the first steps is important, but it is essential to see these as the start of a path toward total decarbonization,” Schrag pointed out. “This means continuing to invest in innovation that can someday replace fossil fuels altogether. Partial reductions are not going to do the job.”

Stocker said that in the last 50 years alone, humans have changed the climate on a global scale, initiating the Anthropocene, a new geological era with fundamentally altered living conditions for the next many thousands of years.

“Because we do not know to what extent adaptation will be possible for humans and ecosystems, all our efforts must focus on a rapid and complete decarbonization –the only option to limit climate change,” Stocker said.

The researchers’ work was supported by the U.S. National Science Foundation, the U.S. Department of Energy, the Natural Sciences and Engineering Research Council of Canada, the German Science Foundation and the Swiss National Science Foundation.

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Peter Clark, 541-737-1247, clarkp@geo.oregonstate.edu;

Thomas Stocker, +41 31 631 44 62, stocker@climate.unibe.ch;

Daniel Schrag, 617-233-2554, schrag@eps.harvard.edu

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Rising sea levels will threaten residents of many countries.

Study: Fish assemblages can change rapidly along coast as water warms

CORVALLIS, Ore. – A modest warming of coastal waters can have a significant impact on juvenile fish assemblages in a period of just a few years, a newly published study has found, raising concern about the potential effects of climate change.

Such a shift is taking place on the Skagerrak coast of Norway, where more warm-water fish species have begun appearing over the past two decades while many populations of resident cold-water fish species have declined.

Results of the study have just been published in the journal Global Change Biology.

Studying the potential impact of climate change on coastal fishes has been difficult, researchers say, because few long-term records adequately address species diversity. But researchers at Norway’s Institute of Marine Research have been conducting what has to be one of the longest, most consistent surveys of near-shore waters ever undertaken – a key to understanding climate change effects.

“What we’re seeing is a clear influence of ocean temperature on the region’s juvenile fish community, which has changed in what is a very important fish nursery area,” said Caren Barceló, an Oregon State University doctoral candidate and lead author on the study. “It has implications for nursery habitats that have been around for decades.”

Barceló, who worked with Norwegian researchers on their beach seine surveys, said no new species had appeared in the waters of Skagerrak for nearly three decades beginning in the mid-1960s. Within the next 15 years, however, several pelagic, planktivorou species more characteristic of the Mediterranean arrived – for example, European anchovy (Engraulis encrasicolus) and European pilchard (Sardina pilchardus).

Other warm-water species of fish present now were documented once before in the area, such as juvenile horse mackerel (Trachurus trachurus), when the water warmed in the 1930s and ‘40s and then became less prevalent when it cooled. The corkwing wrasse (Symphodus melops) is another fish species that appeared during the earlier warm period, then became less prevalent for more than half a century – before returning during the latest warming.

Cold-water species that have been caught less frequently in this dataset over the past two decades include cod (Gadus morhua), pollack (Pollachius pollachius), and European eel (Anguilla anguilla).

One concern, the researchers say, is that the present warming is not an anomaly, rather a symptom of climate change that may worsen instead of going away. There may be other factors involved in the introduction of new species, noted Lorenzo Ciannelli, an Oregon State marine ecologist and co-author on the study.

“There are some unique elements happening today that distinguish the situation from the 1930s and ‘40s,” Ciannelli said. “Winds and currents are pushing warm water into the area in such a way that it suggests the pattern might be here to stay.

“Some fish will move into a new area as adults, while other species disperse their eggs or larva and they then ride into new regions on the currents,” he added. “To make them ‘stick’ there may need to be a seeding process that allows the local population to develop.”

The key to understanding the assemblage shift in Norway is the extraordinary data set collected by Norwegian researchers. For the past 96 years, they have conducted an extensive coast-wide seine survey during the last two weeks of September, using the same style boats, the same locations and nets that were exactly the same size.

Only five survey leaders have coordinated the effort over 96 years, each one having trained with the previous leader for at least 10 years on the operation of setting and hauling the beach seine before taking over the project themselves.

“It began as a project to analyze the recruitment of juvenile cod in the region,” Barceló said, “but someone had the foresight a century ago to document all of the species  brought up in the nets – and they’ve kept it up ever since.”

Barceló, who worked with the Norwegians over two summers, is also analyzing fish surveys off the Oregon coast, investigating the long-term environmental variability and shifting marine fish assemblages.

She and Ciannelli are in OSU’s College of Earth, Ocean, and Atmospheric Sciences.

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Caren Barceló, 541-737-3965, caren.barcelo@gmail.com;

Lorenzo Ciannelli, 541-737-3142, lciannelli@coas.oregonstate.edu

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Caren Barcelo works with Norwegian researchers.

New therapy halts progression of Lou Gehrig’s disease in mice

CORVALLIS, Ore. – Researchers at Oregon State University announced today that they have essentially stopped the progression of amyotrophic lateral sclerosis (ALS), or Lou Gehrig’s disease, for nearly two years in one type of mouse model used to study the disease – allowing the mice to approach their normal lifespan.

The findings, scientists indicate, are some of the most compelling ever produced in the search for a therapy for ALS, a debilitating and fatal disease, and were just published in Neurobiology of Disease.

“We are shocked at how well this treatment can stop the progression of ALS,” said Joseph Beckman, lead author on this study, a distinguished professor of biochemistry and biophysics in the College of Science at Oregon State University, and principal investigator and holder of the Burgess and Elizabeth Jamieson Chair in OSU’s Linus Pauling Institute.

In decades of work, no treatment has been discovered for ALS that can do anything but prolong human survival less than a month. The mouse model used in this study is one that scientists believe may more closely resemble the human reaction to this treatment, which consists of a compound called copper-ATSM.

It’s not yet known if humans will have the same response, but researchers are moving as quickly as possible toward human clinical trials, testing first for safety and then efficacy of the new approach.

ALS was identified as a progressive and fatal neurodegenerative disease in the late 1800s, and gained international recognition in 1939 when it was diagnosed in American baseball legend Lou Gehrig. It’s known to be caused by the death and deterioration of motor neurons in the spinal cord, which in turn has been linked to mutations in copper, zinc superoxide dismutase.

Copper-ATSM is a known compound that helps deliver copper specifically to cells with damaged mitochondria, and reaches the spinal cord where it’s needed to treat ALS. This compound has low toxicity, easily penetrates the blood-brain barrier, is already used in human medicine at much lower doses for some purposes, and is well tolerated in laboratory animals at far higher levels. Any copper not needed after use of copper-ATSM is quickly flushed out of the body.

Experts caution, however, that this approach is not as simple as taking a nutritional supplement of copper, which can be toxic at even moderate doses. Such supplements would be of no value to people with ALS, they said.

The new findings were reported by scientists from OSU; the University of Melbourne in Australia; University of Texas Southwestern; University of Central Florida; and the Pasteur Institute of Montevideo in Uruguay. The study is available as open access in Neurobiology of Disease.

Using the new treatment, researchers were able to stop the progression of ALS in one type of transgenic mouse model, which ordinarily would die within two weeks without treatment. Some of these mice have survived for more than 650 days, 500 days longer than any previous research has been able to achieve.

In some experiments, the treatment was begun, and then withheld. In this circumstance the mice began to show ALS symptoms within two months after treatment was stopped, and would die within another month. But if treatment was resumed, the mice gained weight, progression of the disease once again was stopped, and the mice lived another 6-12 months.

In 2012, Beckman was recognized as the leading medical researcher in Oregon, with the Discovery Award from the Medical Research Foundation of Oregon. He is also director of OSU’s Environmental Health Sciences Center, funded by the National Institutes of Health to support research on the role of the environment in causing disease.

“We have a solid understanding of why the treatment works in the mice, and we predict it should work in both familial and possibly sporadic human patients,” Beckman said. “But we won’t know until we try.”

Familial ALS patients are those with more of a family history of the disease, while sporadic patients reflect the larger general population.

“We want people to understand that we are moving to human trials as quickly as we can,” Beckman said. “In humans who develop ALS, the average time from onset to death is only three to four years.”

The advances are based on substantial scientific progress in understanding the disease processes of ALS and basic research in biochemistry. The transgenic mice used in these studies have been engineered to carry the human gene for “copper chaperone for superoxide dismutase,” or CCS gene. CCS inserts copper into superoxide dismustase, or SOD, and transgenic mice carrying these human genes die rapidly without treatment.

After years of research, scientists have developed an approach to treating ALS that’s based on bringing copper into specific cells in the spinal cord and mitochondria weakened by copper deficiency. Copper is a metal that helps to stabilize SOD, an antioxidant protein whose proper function is essential to life. But when it lacks its metal co-factors, SOD can “unfold” and become toxic, leading to the death of motor neurons.

There’s some evidence that this approach, which works in part by improving mitochondrial function, may also have value in Parkinson’s disease and other conditions, researchers said. Research is progressing on those topics as well. 

The treatment is unlikely to allow significant recovery from neuronal loss already caused by ALS, the scientists said, but could slow further disease progression when started after diagnosis. It could also potentially treat carriers of SOD mutant genes that cause ALS.

This work has been supported by the Department of Defense Congressionally Directed Medical Research Program, the U.S. National Institutes of Health, the Amyotrophic Lateral Sclerosis Association, the Australian National Health and Medical Research Association, and gifts by Michael Camillo and Burgess and Elizabeth Jamieson to the Linus Pauling Institute.

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Joseph Beckman, 541-737-8867

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