OREGON STATE UNIVERSITY

scientific research and advances

Study confirms link between salmon migration and magnetic field

CORVALLIS, Ore. – A team of scientists last year presented evidence of a correlation between the migration patterns of ocean salmon and the Earth’s magnetic field, suggesting it may help explain how the fish can navigate across thousands of miles of water to find their river of origin.

This week, scientists confirmed the connection between salmon and the magnetic field following a series of experiments at the Oregon Hatchery Research Center in the Alsea River basin. Researchers exposed hundreds of juvenile Chinook salmon to different magnetic fields that exist at the latitudinal extremes of their oceanic range. Fish responded to these “simulated magnetic displacements” by swimming in the direction that would bring that toward the center of their marine feeding grounds.

The study, which was funded by Oregon Sea Grant and the Oregon Department of Fish and Wildlife, will be published this month in the forthcoming issue of Current Biology.

“What is particularly exciting about these experiments is that the fish we tested had never left the hatchery and thus we know that their responses were not learned or based on experience, but rather they were inherited,” said Nathan Putman, a postdoctoral researcher in Oregon State University’s Department of Fisheries and Wildlife and lead author on the study.

“These fish are programmed to know what to do before they ever reach the ocean,” he added.

To test the hypothesis, the researchers constructed a large platform with copper wires running horizontally and vertically around the perimeter. By running electrical current through the wires, the scientists could create a magnetic field and control both the intensity and inclination angle of the field. They then placed 2-inch juvenile salmon called “parr” in 5-gallon buckets and, after an acclimation period, monitored and photographed the direction in which they were swimming.

Fish presented with a magnetic field characteristic of the northern limits of the oceanic range of Chinook salmon were more likely to swim in a southerly direction, while fish encountering a far southern field tended to swim north. In essence, fish possess a “map sense” determining where they are and which way to swim based on the magnetic fields they encounter.

“The evidence is irrefutable,” said co-author David Noakes of OSU, senior scientist at the Oregon Hatchery Research Center and the 2012 recipient of the American Fisheries Society’s Award of Excellence. “I tell people: The fish can detect and respond to the Earth’s magnetic field. There can be no doubt of that.”

Not all of the more than 1,000 fish swam in the same direction, Putman said. But there was a clear preference by the fish for swimming in the direction away from the magnetic field that was “wrong” for them. Fish that remained in the magnetic field of the testing site – near Alsea, Ore. – were randomly oriented, indicating that orientation of fish subjected to magnetic displacements could only be attributable to change in the magnetic field.

“What is really surprising is that these fish were only exposed to the magnetic field we created for about eight minutes,” Putman pointed out. “And the field was not even strong enough to deflect a compass needle.”

Putman said that salmon must be particularly sensitive because the Earth’s magnetic field is relatively weak. Because of that, it may not take much to interfere with their navigational abilities. Many structures contain electrical wires or reinforcing iron that could potentially affect the orientation of fish early in their life cycle, the researchers say.

“Fish are raised in hatcheries where there are electrical and magnetic influences,” Noakes said, “and some will encounter electrical fields while passing through power dams. When they reach the ocean, they may swim by structures or cables that could interfere with navigation. Do these have an impact? We don’t yet know.”

Putman said natural disruptions could include chunks of iron in the Earth’s crust, though “salmon have been dealing with that for thousands of years.”

“Juvenile salmon face their highest mortality during the period when the first enter the ocean,” Putman said, “because they have to adapt to a saltwater environment, find food, avoid predation, and begin their journey. Anything that makes them navigate less efficiently is a concern because if they take a wrong turn and end up in a barren part of the ocean, they are going to starve.”

The magnetic field is likely not the only tool salmon use to navigate, however, Putman noted.

“They likely have a whole suite of navigational aids that help them get where they are going, perhaps including orientation to the sun, sense of smell and others,” Putman said.

The Oregon Hatchery Research Center is funded by the Oregon Department of Fish and Wildlife and jointly run by ODFW and Oregon State University.

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Nathan Putman, 205-218-5276; Nathan.putman@oregonstate.edu

David Noakes, 541-737-1953; david.noakes@oregonstate.edu

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Genetic function discovered that could offer new avenue to cancer therapies

The study this story is based on is available online: http://rsc.li/1fcWMim

 

CORVALLIS, Ore. – Researchers at Oregon State University have discovered a genetic function that helps one of the most important “tumor suppressor” genes to do its job and prevent cancer.

Finding ways to maintain or increase the effectiveness of this gene – called Grp1-associated scaffold protein, or Grasp – could offer an important new avenue for human cancer therapies, scientists said.

The findings were just published in Photochemical and Photobiological Sciences, a journal of the Royal Society of Chemistry, by researchers from OSU and Oregon Health & Science University. The work was supported by the National Institute of Environmental Health Sciences.

The Grasp gene was studied in the skin of mice in this research, but is actually expressed at the highest levels in the brain, heart and lung, studies have shown. It appears to play a fundamental role in the operation of the p53 tumor suppressor gene, which is a focus of much modern cancer research.

The p53 gene is involved in repair of DNA damage and, if the damage is too great, causing a mutated cell to die before it can cause further problems, up to and including cancer. Dysfunction of p53 genetic pathways have been linked to more than half of all known cancers - particularly skin, esophageal, colon, pancreatic, lung, ovarian, and head and neck cancers.

“DNA mutations occur constantly in our bodies just by ordinary stresses, something as simple as exposure to sunlight for a few seconds,” said Mark Leid, professor of pharmacology and associate dean for research in the OSU College of Pharmacy, and one of the lead authors on this study.

“Just as constantly, the p53 gene and other tumor suppressors are activated to repair that damage,” Leid said. “And in cases where the damage is too severe to be repaired, p53 will cause the apoptosis, or death of the mutated cell. Almost all of the time, when they are working right, these processes prevent the formation of cancers.”

But the activity and function of p53 can sometimes decline or fail, Leid said, and allow development of cancer. Promising approaches to cancer therapy are now based on activating or stimulating the p53 protein to do its job.

The new study has found that the Grasp gene is significantly involved in maintaining the proper function of p53. When “Grasp” is not being adequately expressed, the p53 protein that has entered the cell nucleus to either repair or destroy the cell comes back out of the nucleus before its work is finished.

“It appears that a primary function of Grasp is to form sort of a halo around the nucleus of a damaged skin cell, and act as kind of a plug to keep the p53 cell inside the nucleus until its work is done,” Leid said. “A drug that could enhance Grasp function might also help enhance the p53 function, and give us a different way to keep this important tumor suppressor working the way that it is supposed to.

“This could be important,” he said.

OSU experts created laboratory mice that lacked the Grasp gene, and so long as the mice were reared in a perfect environment, they developed normally. But when they were exposed to even a mild environmental stress – ultraviolet light similar to moderate sun exposure – they began to develop cellular abnormalities much more rapidly than ordinary mice. Most significantly, mutated skin cells did not die as they should have.

In normal mice, the same moderate light exposure caused a rapid increase in expression of the Grasp gene, allowing the p53 protein to stay in the nucleus and normal protective mechanisms to do their work.

Most current cancer therapies related to the p53 tumor suppression process are directed toward activating the p53 protein, Leid said. A therapy directed toward improving the Grasp gene function would be a different approach toward the same goal, he said, and might improve the efficacy of treatment.

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Mark Leid, 541-737-5809

OSU surpasses fundraising milestone of $1 billion

 

A copy of President Ray’s speech is available online: http://bit.ly/1dRiaHx

CORVALLIS, Ore. – Oregon State University President Edward J. Ray announced today that the university’s first comprehensive campaign has surpassed its $1 billion fund-raising goal – 11 months ahead of schedule.

Ray made the announcement at his annual “State of the University” address in Portland to an audience of more than 600 business, political, civic and education leaders, alumni and friends of the university. He encouraged contributions through the remainder of the year to further deepen the university’s impact on students, the state, nation and world. Gifts to The Campaign for OSU now total $1,012,601,000.

“While this is a remarkable milestone, this campaign has never been about the big number,” Ray said. “Our generous donors are committed, as is the university, to transforming Oregon State into a top-10 land grant research university to significantly advance the health of the Earth, its people and our economy.”

Donors have brought private support for Oregon State to an all-time high, with annual totals exceeding $100 million for the last three years. More than 102,000 donors to the campaign have:

  • Created more than 600 new scholarships and fellowship funds – a 30 percent increase – with gifts for student support exceeding $170 million;
  • Contributed more than $100 million to help attract and retain leading professors and researchers, including funding for 77 of Oregon State’s 124 endowed faculty positions;
  • Supported the construction or renovation of more than two dozen campus facilities, including Austin Hall in the College of Business, the Linus Pauling Science Center, new cultural centers, and the OSU Basketball Center. Bonding support from the state was critical to many of these projects.

 

Business leaders Pat Reser, a 1960 OSU alumna; Patrick Stone, a 1974 graduate; and Jim Rudd have co-chaired the campaign since its public launch in 2007. All three have been trustees of the OSU Foundation, and Reser, board chair of Reser’s Fine Foods, also serves as chair of Oregon State’s new Board of Trustees that was appointed by Oregon Gov. John Kitzhaber.

“Our donor community is growing because people are deepening their ties to Oregon State – and that helps make us a better university,” said J. Michael Goodwin, CEO and president of the OSU Foundation, the nonprofit organization charged with raising, administering and stewarding private gifts to the university.  “This broad base of support positions Oregon State well for future philanthropic support and engagement from our alumni, parents and friends.”

Donors from every state and more than 50 countries have invested in OSU as part of the campaign. Almost 40 percent of these campaign donors are first-time donors to the university. More than 1,000 donors have made campaign gifts of more than $100,000, including 177 donors who have made gifts of $1 million or more. Oregon State joins only 34 other public universities in the country to have crossed the billion-dollar mark in a fund-raising campaign.

“The campaign is about developing and energizing a community of dedicated advocates, people who share our vision of what Oregon State can accomplish,” Ray said. “These partners have changed Oregon State forever – and I believe the best is yet to come.”

In his State of the University address, Ray said Oregon needs to quit talking and start planning to meet its goal of a more educated citizenry to achieve economic and social prosperity. He cited the state’s lack of apparent focus on reaching Oregon’s “40-40-20” educational achievement goal, which calls for 40 percent of adult Oregonians to hold a bachelor’s or advanced degree, 40 percent to have an associate’s degree or a meaningful postsecondary certificate, and all adult Oregonians to hold a high school diploma or equivalent by the year 2025.

OSU has developed a plan to do its part and is committed to those goals, already demonstrating success, Ray said. But more is needed.

“Beyond Oregon State University’s own enrollment management and strategic plan, I have no idea how the state will get to 40-40-20, which could require as many as 35,000 more students annually enrolled in our four-year universities and colleges,” Ray said. “There is no statewide blueprint.”

Ray went on to describe how OSU’s enrollment grew by 1,532 students in Corvallis and online and by another 135 students at OSU-Cascades in Bend.

“Despite those gains, the net increase in enrollment among all Oregon public universities outside of Oregon State totaled 14 students,” Ray pointed out. That includes an enrollment increase at the Oregon Institute of Technology of 413 students.

OSU has been following a plan for the past two years to help the state achieve its goals. Ray said the university expects to educate 28,000 students in Corvallis, 3,000 to 5,000 students at OSU-Cascades by 2025; and grow its online enrollment to more than 7,000 students. The university also plans to educate another 500 students annually by 2025 at a new marine studies campus located in Newport.

Ray, who recently completed his 10th year as OSU president, pointed to several Oregon State University initiatives that will help boost the economy:

 

  • OSU will lead a new national effort through its College of Forestry to advance the science and technology necessary to utilize wood in the construction of taller buildings in a public-private partnership that will advance manufacturing in Oregon and boost rural economies;
  • The university launched the OSU Advantage last year – a one-stop shop for linking businesses with the students and researchers of Oregon State to accelerate new business development and spinoff companies;
  • OSU’s research enterprise continues to grow and reached $263 million in 2013 – a 70 percent increase over the last decade. Two major initiatives include the selection of Oregon State to lead the design and construction of the next generation of ocean-going research vessels for the United States, and the selection of OSU, along with partners in Alaska and Hawaii, to operate one of six national sites for unmanned aircraft systems.

Industry-sponsored research is up 60 percent in five years, Ray pointed out, and licensing agreements with industry have increased 83 percent. Since 2006, OSU has helped launched 20 startup companies, which have raised $190 million in venture capital and created hundreds of jobs.

“Economic development,” Ray said, “is part of our DNA.”

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Steve Clark, 503-502-8217

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Study identifies high level of “food insecurity” among college students

 

The study this story is based on is available in ScholarsArchive@OSU: http://bit.ly/LCp10Y

 

CORVALLIS, Ore. – One of the few studies of its type has found that a startling 59 percent of college students at one Oregon university were “food insecure” at some point during the previous year, with possible implications for academic success, physical and emotional health and other issues.

Contrary to concerns about obesity and some students packing on “the freshman 15” in weight gain, another reality is that many students are not getting enough healthy food to eat as they struggle with high costs, limited income, and fewer food or social support systems than are available to other groups.

The findings were published recently in the Journal of Nutrition Education and Behavior, by researchers from Oregon State University, the Benton County Health Department, and Western Oregon University. Students at Western Oregon were surveyed as the basis for the study.

“Based on other research that’s been done, we expected some amount of food concerns among college students,” said Daniel López-Cevallos, associate director of research at OSU’s Center for Latino/a Studies and Engagement. “But it was shocking to find food insecurity of this severity. Several recent trends may be combining to cause this.”

The researchers said a combination of rising college costs, more low-income and first-generation students attending college, and changing demographic trends are making this issue more significant than it may have been in the past.

“For past generations, students living on a lean budget might have just considered it part of the college experience, a transitory thing,” said Megan Patton-López, lead author of the study with Oregon’s Benton County Health Department.

“But rising costs of education are now affecting more people,” she said. “And for many of these students who are coming from low-income families and attending college for the first time, this may be a continuation of food insecurity they’ve known before. It becomes a way of life, and they don’t have as many resources to help them out.”

Most college students, with some exceptions, are not eligible for food stamps and many are often already carrying heavy debt loads. And the study found that even though many of them work one or more jobs, the financial demands are such that they still may not have enough money for healthy food at all times.

Food insecurity is defined as limited or uncertain availability of nutritionally adequate and safe foods, and the ability to acquire such food in acceptable ways. It has been associated with depression, stress, trouble learning in the classroom, and poor health. When similar issues have been addressed with elementary school students, improvements were seen in academic performance, behavior and retention of knowledge.

But these problems have received scarcely any attention in the 19-24 year old, young-adult demographic that predominates in college, the scientists said.

Among the findings of this study:

  • While about 14.9 percent of all households in the nation report food insecurity, the number of college students voicing similar concerns in this report was almost four times higher, at 59 percent.
  • In the past three decades the cost of higher education has steadily outpaced inflation, the cost of living and medical expenses.
  • Food insecurity during college years could affect cognitive, academic and psychosocial development.
  • Factors correlated with reports of food insecurity include fair to poor health, a lower grade point average, low income and employment.

Employment, by itself, is not adequate to resolve this problem, the researchers found. Students reporting food insecurity also worked an average of 18 hours a week – some as high as 42 – but the financial demands they faced more than offset that income.

These findings were based on a survey of 354 students at Western Oregon University, a mid-size public university in a small town near the state capitol in Salem, Ore. Students at Western Oregon supported and assisted in this research, and Doris Cancel-Tirado and Leticia Vazquez with Western Oregon co-authored the study.

The findings probably reflect similar concerns at colleges and universities across the nation, the researchers said, although more research is needed in many areas to determine the full scope of this problem.

“One thing that’s clear is that colleges and universities need to be having this conversation and learning more about the issues their students may be facing,” said López-Cevallos. “There may be steps to take locally that could help, and policies that could be considered nationally. But it does appear this is a very serious issue that has not received adequate attention, and we need to explore it further.”

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Daniel López-Cevallos, 541-737-3850

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More benefits emerging for one type of omega-3 fatty acid: DHA

The study this story is based on is available online: http://bit.ly/1dDuf7i

 

CORVALLIS, Ore. – A study of the metabolic effects of omega-3 fatty acids, especially DHA, concludes that these compounds may have an even wider range of biological impacts than previously considered, and suggests they could be of significant value in the prevention of fatty liver disease.

The research, done by scientists at Oregon State University and several other institutions, was one of the first of its type to use “metabolomics,” an analysis of metabolites that reflect the many biological effects of omega-3 fatty acids on the liver. It also explored the challenges this organ faces from the “Western diet” that increasingly is linked to liver inflammation, fibrosis, cirrhosis and sometimes liver failure.

The results were surprising, researchers say.

Supplements of DHA, used at levels that are sometimes prescribed to reduce blood triglycerides, appeared to have many unanticipated effects. There were observable changes in vitamin and carbohydrate metabolism, protein and amino acid function, as well as lipid metabolism.

Supplementation with DHA partially or totally prevented metabolic damage through those pathways often linked to the Western diet – excessive consumption of red meat, sugar, saturated fat and processed grains.

The findings were published last month in PLOS One, an online professional journal.

“We were shocked to find so many biological pathways being affected by omega-3 fatty acids,” said Donald Jump, a professor in the OSU College of Public Health and Human Sciences. “Most studies on these nutrients find effects on lipid metabolism and inflammation.

“Our metabolomics analysis indicates that the effects of omega-3 fatty acids extend beyond that, and include carbohydrate, amino acid and vitamin metabolism,” he added.

Omega-3 fatty acids have been the subject of much recent research, often with conflicting results and claims. Possible reasons for contradictory findings, OSU researchers say, are the amount of supplements used and the relative abundance of two common omega-3s – DHA and EPA. Studies at OSU have concluded that DHA has far more ability than EPA to prevent the formation of harmful metabolites. In one study, it was found that DHA supplementation reduced the proteins involved in liver fibrosis by more than 65 percent.

These research efforts, done with laboratory animals, used a level of DHA supplementation that would equate to about 2-4 grams per day for an average person. In the diet, the most common source of DHA is fatty fish, such as salmon, mackerel or sardines.

The most recent research is beginning to break down the specific processes by which these metabolic changes take place. If anything, the results suggest that DHA may have even more health value than previously thought.

“A lot of work has been done on fatty liver disease, and we are just beginning to explore the potential for DHA in preventing or slowing disease progression,” said Jump, who is also a principal investigator in OSU’s Linus Pauling Institute.

“Fish oils, a common supplement used to provide omega-3, are also not prescribed to regulate blood glucose levels in diabetic patients,” he said. “But our studies suggest that DHA may reduce the formation of harmful glucose metabolites linked to diabetic complications.”

Both diabetes and liver disease are increasing steadily in the United States.

The American Liver Foundation has estimated that about 25 percent of the nation’s population, and 75 percent of those who are obese, have nonalcoholic fatty liver disease. This can progress to nonalcoholic steatohepatitis, cirrhosis and cancer.

This study established that the main target of DHA in the liver is the control of inflammation, oxidative stress and fibrosis, which are the characteristics of more progressively serious liver problems. Omega-3 fatty acids appear to keep cells from responding to and being damaged by whatever is causing inflammation.

Collaborators on this research were from OSU, the Baylor College of Medicine, Vanderbilt University Medical Center, and Metabolon, Inc. It was supported by the USDA and the National Institutes of Health.

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Donald Jump, 541-737-4007

War on lionfish shows first promise of success

 

 

The study this story is based on is available online: http://bit.ly/1f9fqbg

 

CORVALLIS, Ore. – It may take a legion of scuba divers armed with nets and spears, but a new study confirms for the first time that controlling lionfish populations in the western Atlantic Ocean can pave the way for a recovery of native fish.

Even if it’s one speared fish at a time, it finally appears that there’s a way to fight back.

Scientists at Oregon State University, Simon Fraser University and other institutions have shown in both computer models and 18 months of field tests on reefs that reducing lionfish numbers by specified amounts – at the sites they studied, between 75-95 percent – will allow a rapid recovery of native fish biomass in the treatment area, and to some extent may aid larger ecosystem recovery as well.

It’s some of the first good news in a struggle that has at times appeared almost hopeless, as this voracious, invasive species has wiped out 95 percent of native fish in some Atlantic locations.

“This is excellent news,” said Stephanie Green, a marine ecologist in the College of Science at Oregon State University, and lead author on the report just published in Ecological Applications. “It shows that by creating safe havens, small pockets of reef where lionfish numbers are kept low, we can help native species recover.

“And we don’t have to catch every lionfish to do it.”

That’s good, researchers say, because the rapid spread of lionfish in the Atlantic makes eradication virtually impossible. They’ve also been found thriving in deep water locations which are difficult to access.

The latest research used ecological modeling to determine what percentage of lionfish would have to be removed at a given location to allow for native fish recovery. At 24 coral reefs near Eleuthera Island in the Bahamas, researchers then removed the necessary amount of lionfish to reach this threshold, and monitored recovery of the ecosystem.

On reefs where lionfish were kept below threshold densities, native prey fish increased by 50-70 percent. It’s one of the first studies of its type to demonstrate that reduction of an invasive species below an environmentally damaging threshold, rather than outright eradication, can have comparable benefits.

Some of the fish that recovered, such as Nassau grouper and yellowtail snapper, are critically important to local economies. And larger adults can then spread throughout the reef system – although the amount of system recovery that would take place outside of treated areas is a subject that needs additional research, they said.

Where no intervention was made, native species continued to decline and disappear.

The lionfish invasion in the Atlantic, believed to have begun in the 1980s, now covers an area larger than the entirety of the United States. With venomous spines, no natural predators in the Atlantic Ocean, and aggressive behavior, the lionfish have been shown to eat almost anything smaller than they are – fish, shrimp, crabs and octopus. Lionfish can also withstand starvation for protracted periods – many of their prey species will disappear before they do.

Governments, industry and conservation groups across this region are already trying to cull lionfish from their waters, and encourage their use as a food fish. Some removal efforts have concentrated on popular dive sites.

The scientists said in their report that the model used in this research should work equally well in various types of marine habitat, including mangroves, temperate hard-bottom systems, estuaries and seagrass beds.

A major issue to be considered, however, is where to allocate future removal efforts. Marine reserves, which often allow “no take” of any marine life in an effort to recover fish populations, may need to be the focus of lionfish removal. The traditional, hands-off concept in such areas may succeed only in wiping out native species while allowing the invasive species to grow unchecked.

Keeping lionfish numbers low in areas that are hot spots for juvenile fish, like mangroves and shallow reefs, is also crucial, the report said.

This research was done in collaboration with scientists at Simon Fraser University, the Reef Environmental Education Foundation, and the Cape Eleuthera Institute. It has been supported by the Natural Science and Engineering Research Council of Canada, the Boston Foundation and a David H. Smith Conservation Research Fellowship.

“Many invasions such as lionfish are occurring at a speed and magnitude that outstrips the resources available to contain and eliminate them,” the researchers wrote in their conclusion. “Our study is the first to demonstrate that for such invasions, complete extirpation is not necessary to minimize negative ecological changes within priority habitats.”

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Stephanie Green, 541-908-3839

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Video of researcher netting lionfish in the Bahamas:

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One step at a time, researchers learning how humans walk

 

 

The study this story is based on is available online: http://bit.ly/1d1KZ3u

 

CORVALLIS, Ore. – Humans and some of our hominid ancestors such as Homo erectus have been walking for more than a million years, and researchers are close to figuring out how we do it.

It’s never been completely clear how human beings accomplish the routine, taken-for-granted miracle we call walking, let alone running. But findings published last month in the Journal of Experimental Biology outline a specific interaction between the ankle, knee, muscles and tendons that improve the understanding of a leg moving forward in a way that maximizes motion while using minimal amounts of energy.

The research could find some of its earliest applications in improved prosthetic limbs, said researchers in the College of Engineering at Oregon State University. Later on, a more complete grasp of these principles could lead to walking or running robots that are far more agile and energy-efficient than anything that exists today.

“Human walking is extraordinarily complex and we still don’t understand completely how it works,” said Jonathan Hurst, an OSU professor of mechanical engineering and expert in legged locomotion in robots. There’s a real efficiency to it – walking is almost like passive falling. The robots existing today don’t walk at all like humans, they lack that efficiency of motion and agility.

“When we fully learn what the human leg is doing,” Hurst added, “we’ll be able to build robots that work much better.”

Researchers have long observed some type of high-power “push off” when the leg leaves the ground, but didn’t really understand how it worked. Now they believe they do. The study concluded there are two phases to this motion. The first is an “alleviation” phase in which the trailing leg is relieved of the burden of supporting the body mass.

Then in a “launching” phase the knee buckles, allowing the rapid release of stored elastic energy in the ankle tendons, like the triggering of a catapult.

“We calculated what muscles could do and found it insufficient, by far, for generating this powerful push off,” said Daniel Renjewski, a postdoctoral research associate in the Dynamic Robotics Laboratory at OSU. “So we had to look for a power-amplifying mechanism.

“The coordination of knee and ankle is critical,” he said. “And contrary to what some other research has suggested, the catapult energy from the ankle is just being used to swing the leg, not add large amounts of energy to the forward motion.”

Walking robots don’t do this. Many of them use force to “swing” the leg forward from something resembling a hip point. It can be functional, but it’s neither energy-efficient nor agile. And for more widespread use of mobile robots, energy use is crucially important, the researchers said.

“We still have a long way to go before walking robots can move with as little energy as animals use,” Hurst said. “But this type of research will bring us closer to that.”

The research was supported by the German Research Foundation. The Dynamic Robotics Laboratory at OSU is supported by the Human Frontier Science Program, the National Science Foundation and the Defense Advanced Research Projects Agency, and has helped create some of the leading technology in the world for robots that can walk and run.

One model can run a nine-minute mile and step off a ledge, and others are even more advanced. Robots with the ability to walk and maneuver over uneven terrain could ultimately find applications in prosthetic limbs, an exo-skeleton to assist people with muscular weakness, or use in the military, disaster response or any dangerous situation.

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Jonathan Hurst, 541-737-7010

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Loss of large carnivores poses global conservation problem

CORVALLIS, Ore. – In ecosystems around the world, the decline of large predators such as lions, dingoes, wolves, otters, and bears is changing the face of landscapes from the tropics to the Arctic – but an analysis of 31 carnivore species to be published Friday in the journal Science shows for the first time how threats such as habitat loss, persecution by humans and loss of prey combine to create global hotspots of carnivore decline.

More than 75 percent of the 31 large-carnivore species are declining, and 17 species now occupy less than half of their former ranges, the authors reported.

Southeast Asia, southern and East Africa and the Amazon are among areas in which multiple large carnivore species are declining. With some exceptions, large carnivores have already been exterminated from much of the developed world, including Western Europe and the eastern United States.

“Globally, we are losing our large carnivores,” said William Ripple, lead author of the paper and a professor in the Department of Forest Ecosystems and Society at Oregon State University.

“Many of them are endangered,” he said. “Their ranges are collapsing. Many of these animals are at risk of extinction, either locally or globally. And, ironically, they are vanishing just as we are learning about their important ecological effects.”

Ripple and colleagues from the United States, Australia, Italy and Sweden called for an international initiative to conserve large predators in coexistence with people. They suggested that such an effort be modeled on the Large Carnivore Initiative for Europe, a nonprofit scientific group affiliated with the International Union for the Conservation of Nature.

The researchers reviewed published scientific reports and singled out seven species that have been studied for their widespread ecological effects or “trophic cascades.” This includes African lions, leopards, Eurasian lynx, cougars, gray wolves, sea otters and dingoes.

Ripple and his Oregon State co-author Robert Beschta have documented impacts of cougars and wolves on the regeneration of forest stands and riparian vegetation in Yellowstone and other national parks in North America. Fewer predators, they have found, lead to an increase in browsing animals such as deer and elk. More browsing disrupts vegetation, shifts birds and small mammals and changes other parts of the ecosystem in a widespread cascade of impacts.

Studies of Eurasian lynx, dingoes, lions and sea otters have found similar effects, the authors reported.

Lynx have been closely tied to the abundance of roe deer, red fox and hare. In Australia, the construction of a 3,400-mile dingo-proof fence has enabled scientists to study ecosystems with and without the animals, which are closely related to gray wolves. In some parts of Africa, the decrease of lions and leopards has coincided with a dramatic increase in olive baboons, which threaten farm crops and livestock. In the waters off southeast Alaska, a decline in sea otters through killer whale predation has led to a rise in sea urchins and loss of kelp beds.

The authors call for a deeper understanding of the impact of large carnivores on ecosystems, a view that they trace back to the work of landmark ecologist Aldo Leopold. The classic concept that predators are harmful and deplete fish and wildlife is outdated, they said. Scientists and wildlife managers need to recognize a growing body of evidence for the complex roles that carnivores play in ecosystems and for their social and economic benefits.

Leopold recognized such relationships between predators and ecosystems, Ripple said, but his observations on that point were largely ignored for decades after his death in 1948.

“Human tolerance of these species is a major issue for conservation,” Ripple said. “We say these animals have an intrinsic right to exist, but they are also providing economic and ecological services that people value.”

Among the services that have been documented in other studies are carbon sequestration, riparian restoration, biodiversity and disease control.

Where large carnivores have been restored — such as wolves in Yellowstone or Eurasian lynx in Finland — ecosystems have responded quickly, said Ripple. “I am impressed with how resilient the Yellowstone ecosystem is. It isn’t happening quickly everywhere, but in some places, ecosystem restoration has started there.”

In those cases, where loss of vegetation has led to soil erosion, for example, full restoration in the near term may not be possible, he said.

“Nature is highly interconnected,” said Ripple. “The work at Yellowstone and other places shows how one species affects another and another through different pathways. It’s humbling as a scientist to see the interconnectedness of nature.”

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Bill Ripple, 541-737-3056

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Leopard. credit Kirstin Abley copy 2
Leopard


Dingo, credit Ken Shaw copy 2
Dingo


Gray Wolf, credit- Doug McLaughlin copy 2
Gray Wolf


Sea otter, credit Norman S. Smith copy
Sea Otter


Eurasian lynx, credit Bodel Elmhagen copy
Eurasian Lynx


puma also known as cougar, credit william ripple
Puma

lion, credit kirstin abley
African Lion

New compounds discovered that are hundreds of times more mutagenic

CORVALLIS, Ore. – Researchers at Oregon State University have discovered novel compounds produced by certain types of chemical reactions – such as those found in vehicle exhaust or grilling meat - that are hundreds of times more mutagenic than their parent compounds which are known carcinogens.

These compounds were not previously known to exist, and raise additional concerns about the health impacts of heavily-polluted urban air or dietary exposure. It’s not yet been determined in what level the compounds might be present, and no health standards now exist for them.

The findings were published in December in Environmental Science and Technology, a professional journal.

The compounds were identified in laboratory experiments that mimic the type of conditions which might be found from the combustion and exhaust in cars and trucks, or the grilling of meat over a flame.

“Some of the compounds that we’ve discovered are far more mutagenic than we previously understood, and may exist in the environment as a result of heavy air pollution from vehicles or some types of food preparation,” said Staci Simonich, a professor of chemistry and toxicology in the OSU College of Agricultural Sciences.

“We don’t know at this point what levels may be present, and will explore that in continued research,” she said.

The parent compounds involved in this research are polycyclic aromatic hydrocarbons, or PAHs, formed naturally as the result of almost any type of combustion, from a wood stove to an automobile engine, cigarette or a coal-fired power plant. Many PAHs, such as benzopyrene, are known to be carcinogenic, believed to be more of a health concern that has been appreciated in the past, and are the subject of extensive research at OSU and elsewhere around the world.

The PAHs can become even more of a problem when they chemically interact with nitrogen to become “nitrated,” or NPAHs, scientists say. The newly-discovered compounds are NPAHs that were unknown to this point.

This study found that the direct mutagenicity of the NPAHs with one nitrogen group can increase 6 to 432 times more than the parent compound. NPAHs based on two nitrogen groups can be 272 to 467 times more mutagenic. Mutagens are chemicals that can cause DNA damage in cells that in turn can cause cancer.

For technical reasons based on how the mutagenic assays are conducted, the researchers said these numbers may actually understate the increase in toxicity – it could be even higher.

These discoveries are an outgrowth of research on PAHs that was done by Simonich at the Beijing Summer Olympic Games in 2008, when extensive studies of urban air quality were conducted, in part, based on concerns about impacts on athletes and visitors to the games.

Beijing, like some other cities in Asia, has significant problems with air quality, and may be 10-50 times more polluted than some major urban areas in the U.S. with air concerns, such as the Los Angeles basin.

An agency of the World Health Organization announced last fall that it now considers outdoor air pollution, especially particulate matter, to be carcinogenic, and cause other health problems as well. PAHs are one of the types of pollutants found on particulate matter in air pollution that are of special concern.

Concerns about the heavy levels of air pollution from some Asian cities are sufficient that Simonich is doing monitoring on Oregon’s Mount Bachelor, a 9,065-foot mountain in the central Oregon Cascade Range. Researchers want to determine what levels of air pollution may be found there after traveling thousands of miles across the Pacific Ocean.

This work was supported by the National Institute of Environmental Health Sciences and the National Science Foundation. It’s also an outgrowth of the Superfund Research Program at OSU, funded by the NIEHS, that focuses efforts on PAH pollution. Researchers from the OSU College of Science, the University of California-Riverside, Texas A&M University, and Peking University collaborated on the study.

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Staci Simonich, 541-737-9194

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Grilled meat

Grilled meat

Amber fossil reveals ancient reproduction in flowering plants

CORVALLIS, Ore. – A 100-million-year old piece of amber has been discovered which reveals the oldest evidence of sexual reproduction in a flowering plant – a cluster of 18 tiny flowers from the Cretaceous Period – with one of them in the process of making some new seeds for the next generation.

The perfectly-preserved scene, in a plant now extinct, is part of a portrait created in the mid-Cretaceous when flowering plants were changing the face of the Earth forever, adding beauty, biodiversity and food. It appears identical to the reproduction process that “angiosperms,” or flowering plants still use today.

Researchers from Oregon State University and Germany published their findings on the fossils in the Journal of the Botanical Institute of Texas.

The flowers themselves are in remarkable condition, as are many such plants and insects preserved for all time in amber. The flowing tree sap covered the specimens and then began the long process of turning into a fossilized, semi-precious gem. The flower cluster is one of the most complete ever found in amber and appeared at a time when many of the flowering plants were still quite small.

Even more remarkable is the microscopic image of pollen tubes growing out of two grains of pollen and penetrating the flower’s stigma, the receptive part of the female reproductive system. This sets the stage for fertilization of the egg and would begin the process of seed formation – had the reproductive act been completed.

“In Cretaceous flowers we’ve never before seen a fossil that shows the pollen tube actually entering the stigma,” said George Poinar, Jr., a professor emeritus in the Department of Integrative Biology at the OSU College of Science. “This is the beauty of amber fossils. They are preserved so rapidly after entering the resin that structures such as pollen grains and tubes can be detected with a microscope.”

The pollen of these flowers appeared to be sticky, Poinar said, suggesting it was carried by a pollinating insect, and adding further insights into the biodiversity and biology of life in this distant era. At that time much of the plant life was composed of conifers, ferns, mosses, and cycads.  During the Cretaceous, new lineages of mammals and birds were beginning to appear, along with the flowering plants. But dinosaurs still dominated the Earth.

“The evolution of flowering plants caused an enormous change in the biodiversity of life on Earth, especially in the tropics and subtropics,” Poinar said.

“New associations between these small flowering plants and various types of insects and other animal life resulted in the successful distribution and evolution of these plants through most of the world today,” he said. “It’s interesting that the mechanisms for reproduction that are still with us today had already been established some 100 million years ago.”

The fossils were discovered from amber mines in the Hukawng Valley of Myanmar, previously known as Burma. The newly-described genus and species of flower was named Micropetasos burmensis.

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Ancient flowers

Ancient flower


Pollen tubes

Pollen tubes