scientific research and advances

Scientists prepare for another wave of tsunami debris, possible invasives

NEWPORT, Ore. – Scientists monitoring incoming tsunami debris were taken aback last spring when some 30 fishing vessels from Japan washed ashore along the Pacific Northwest coast – many of them covered in living organisms indigenous to Asia.

Incidence of wayward skiffs and other tsunami debris subsequently declined sharply over the summer because of seasonal shifts in the winds. Now, those winds and currents have returned to their winter-spring pattern and scientists are expecting more items to wash ashore – even though it is nearing four years since a massive earthquake and tsunami shook Japan.

Blue mussels have been found on literally every boat that has washed ashore and some 200 different species overall have been documented on tsunami debris, according to John Chapman, an Oregon State University marine invasive species specialist at OSU’s Hatfield Marine Science Center.

“The crustaceans and bivalves are of particular concern because they could introduce new diseases, and compete with, displace or otherwise affect our oyster or mussel populations,” Chapman noted.

Just last week, a tote with numerous mussels washed up at Seal Rock – a sign that debris will still be arriving over the next few months. Of particular concern are boats and large objects that wash ashore carrying a variety of living organisms – including some new species that were not aboard the now-infamous dock that landed on Agate Beach near Newport, Ore., in June of 2012.

“We continue to find new organisms that we have never seen before,” Chapman said. “There isn’t as much diversity aboard the Japanese fishing vessels as there was on the dock, but each new species that we haven’t seen before is a cause for concern.

“No one can predict if these new species may gain a foothold in Northwest waters – and what impacts that may have,” he added.

Chapman and OSU colleague Jessica Miller have examined roughly a dozen boats that have washed ashore from the southern Oregon coast to the central Washington coast. Most of them were similar in style – long, narrow skiffs up to 30 feet in length, with no motors. As they drift from Asia to the West Coast of North America, they pick up a variety of organisms along the way.

“We’ve been surprised at the tenacity of some of these coastal Asian organisms that are arriving on the tsunami debris because the middle of the ocean isn’t the most biologically productive place for coastal species,” Miller said.

Among some of the species the Oregon State biologists have encountered over the past year are bat stars, which are sea stars that look like they have bat wings; striped knifejaw, fish that were found alive in at least one boat; and numerous small crustaceans.

Teams of scientists from around the North Pacific region, including Chapman and Miller, have identified more than 165 species that were aboard the original dock, and another 40-50 species that were found on other debris items, including boats. The rate of incoming debris should be slowing, the researchers say, but the arrival of so many boats last spring suggests that the threat is not over.

Invasive marine species are a problem on the West Coast, where they usually are introduced via ballast water from ships. OSU’s Chapman is well aware of the issue; for several years he has studied a parasitic isopod called Griffen’s isopod that was introduced from Asia. Griffen’s isopod infests mud shrimp in estuaries from California to Vancouver Island and is decimating their populations.

The OSU researchers are working with other scientists on the West Coast, who are attempting to genetically identify all of the species arriving on tsunami debris using genomic sampling – work led by Jon Geller of Moss Landing Marine Laboratory. Geller and his students also are collecting samples of marine life in Northwest coastal and estuary communities to look for evidence that non-native species may have established.

“We’re also doing a lot of old-fashioned looking,” Chapman said. “But new species can be difficult to identify if you aren’t searching for them directly in the first place. So we’ve identified three species that are particularly abundant in Asia, appear highly suited for invading the open coast, and would be readily apparent to searchers looking in the right place.”

These species include a hydroid, Eutima; a fly, Telmatogeton; and an amphipod crustacean, Caprella cristibrachium.

Media Contact: 

John Chapman, 541-867-0235;

Jessica Miller, 541-867-0381

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Science study links greenhouse gases to African rainfall

CORVALLIS, Ore. – Scientists may have solved a long-standing enigma known as the African Humid Period – an intense increase in cumulative rainfall in parts of Africa that began after a long dry spell following the end of the last ice age and lasting nearly 10,000 years.

In a new study published this week in Science, an international research team linked the increase in rainfall in two regions of Africa thousands of years ago to an increase in greenhouse gas concentrations. The study was funded by the National Science Foundation and the U.S. Department of Energy.

The findings are critical, researchers say, because they provide new evidence that increases in carbon dioxide and other greenhouse gases could have a significant impact on the future climate of Africa.

“This study is important not only because it explains a long-standing puzzle, but it helps to validate model predictions of how rising greenhouse gas concentrations might change rainfall patterns in a highly populated and vulnerable part of the world,” said Peter Clark, an Oregon State University paleoclimatologist and co-author on the study.

The study was led by the National Center for Atmospheric Research (NCAR). It used computer simulations and analysis of geologic records of past climate.

The researchers focused on the era following the last ice age. When ice sheets covering North America and northern Europe began retreating after the last glacial maximum some 21,000 years ago, there was a long dry spell in central Africa that lasted until about 14,700 years ago, when rainfall increased abruptly. Scientists have long been puzzled by the regime shift, which turned deserts into grasslands and earned the African Humid Period moniker.

Rainfall actually increased in two separate regions of Africa – one north of the equator, the other south. Some previous studies had suggested that the shift may have been triggered by changes in the Earth’s orbit, but lead author Bette Otto-Bliesner said orbital patterns alone could not explain increased rainfall of that extent in both regions.

As the Earth emerged from the ice age, atmospheric levels of carbon dioxide and methane increased significantly – almost to pre-industrial levels – by 11,000 years ago. As the planet continued warming, ice sheets melted and the influx of fresh water from North America and northern Europe began weakening the Atlantic Meridional Overturning Circulation, which brings warm water up from the tropics and keeps Europe temperate.

This weakening of the Atlantic ocean current simultaneously moved precipitation southward toward the southernmost part of Africa, and suppressed rainfall in east Africa and northern equatorial Africa during the long dry spell, the researchers say.

When the ice sheets stopped melting, the circulation strengthened and brought precipitation back to the north. This change, coupled with the orbital shift and warming of both the atmosphere and oceans by greenhouse gases, triggered the African Humid Period.

“This study provides yet another demonstration of the sensitivity of the Earth’s climate to small changes in atmospheric greenhouse gases,” said Clark, a professor in OSU’s College of Earth, Ocean, and Atmospheric Sciences.

The science team recreated records of past moisture conditions by examining fossils, former lake levels and other geologic data, and simulated past climate with a power climate model developed by NCAR.

”The future impact of greenhouse gases on rainfall in Africa is a critical socioeconomic issue,” Otto-Bliesner said. “Africa’s climate seems destined to change, with far-reaching implications for water resources and agriculture in ways that may generate new conflicts.”

The study focused on the Sahel region of Africa to the north, including Niger, Chad and northern Nigeria; and the southeastern equatorial region of Africa, including the Democratic Republic of Congo, Rwanda, Burundi, Tanzania and Kenya.

Media Contact: 

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

Atmospheric carbon dioxide used for energy storage products

CORVALLIS, Ore. – Chemists and engineers at Oregon State University have discovered a fascinating new way to take some of the atmospheric carbon dioxide that’s causing the greenhouse effect and use it to make an advanced, high-value material for use in energy storage products.

This innovation in nanotechnology won’t soak up enough carbon to solve global warming, researchers say. However, it will provide an environmentally friendly, low-cost way to make nanoporous graphene for use in “supercapacitors” – devices that can store energy and release it rapidly.

Such devices are used in everything from heavy industry to consumer electronics.

The findings were just published in Nano Energy by scientists from the OSU College of Science, OSU College of Engineering, Argonne National Laboratory, the University of South Florida and the National Energy Technology Laboratory in Albany, Ore. The work was supported by OSU.

In the chemical reaction that was developed, the end result is nanoporous graphene, a form of carbon that’s ordered in its atomic and crystalline structure. It has an enormous specific surface area of about 1,900 square meters per gram of material. Because of that, it has an electrical conductivity at least 10 times higher than the activated carbon now used to make commercial supercapacitors.

“There are other ways to fabricate nanoporous graphene, but this approach is faster, has little environmental impact and costs less,” said Xiulei (David) Ji, an OSU assistant professor of chemistry in the OSU College of Science and lead author on the study. “The product exhibits high surface area, great conductivity and, most importantly, it has a fairly high density that is comparable to the commercial activated carbons.

“And the carbon source is carbon dioxide, which is a sustainable resource, to say the least,” Ji said. “This methodology uses abundant carbon dioxide while making energy storage products of significant value.”

Because the materials involved are inexpensive and the fabrication is simple, this approach has the potential to be scaled up for production at commercial levels, Ji said.

The chemical reaction outlined in this study involved a mixture of magnesium and zinc metals, a combination discovered for the first time. These are heated to a high temperature in the presence of a flow of carbon dioxide to produce a controlled “metallothermic” reaction. The reaction converted the elements into their metal oxides and nanoporous graphene, a pure form of carbon that’s remarkably strong and can efficiently conduct heat and electricity. The metal oxides could later be recycled back into their metallic forms to make an industrial process more efficient.

By comparison, other methods to make nanoporous graphene often use corrosive and toxic chemicals, in systems that would be challenging to use at large commercial levels.

“Most commercial carbon supercapacitors now use activated carbon as electrodes, but their electrical conductivity is very low,” Ji said. “We want fast energy storage and release that will deliver more power, and for that purpose the more conductive nanoporous graphene will work much better. This solves a major problem in creating more powerful supercapacitors.”

A supercapacitor is a type of energy storage device, but it can be recharged much faster than a battery and has a great deal more power. They are mostly used in any type of device where rapid power storage and short, but powerful energy release is needed.

They are being used in consumer electronics, and have applications in heavy industry, with the ability to power anything from a crane to a forklift. A supercapacitor can capture energy that might otherwise be wasted, such as in braking operations. And their energy storage abilities may help “smooth out” the power flow from alternative energy systems, such as wind energy.

They can power a defibrillator, open the emergency slides on an aircraft and greatly improve the efficiency of hybrid electric automobiles. Nanoporous carbon materials can also adsorb gas pollutants, work as environmental filters, or be used in water treatment. The uses are expanding constantly and have been constrained mostly by their cost.

Media Contact: 

Xiulei (David) Ji, 541-737-6798

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Nanoporous graphene
Nanoporous graphene

PNAS study: Ocean biota responds to global warming

CORVALLIS, Ore. – As the Earth warmed coming out of the last ice age, the rate of plankton production off the Pacific Northwest coast decreased, a new study has found, though the amount of organic material making its way to the deep ocean actually increased.

This suggests that during future climate warming, the ocean may be more efficient than previously thought at absorbing carbon dioxide from the atmosphere – at least in some regions – but raises new concerns about impacts on marine life.

Results of the study are being published online today in Proceedings of the National Academy of Sciences.

The ocean absorbs carbon dioxide like a sponge; scientists say that about one-third of all CO2   emitted historically by burning fossil fuels is now in the ocean. “This is a good news/bad news situation,” said Alan Mix, an Oregon State University oceanographer and co-author on the study. “It helps to slow the rise of CO2 in the atmosphere, but it makes the ocean more acidic.”

A major uncertainty has been how life in the ocean will respond to increasing CO2   and global warming. Growth of phytoplankton (microscopic plants such as diatoms) near the sea surface converts carbon dioxide into organic matter. When the plankton die, their organic remains either decompose in the surface ocean, or sink into the abyss.

This sinking of plankton effectively pumps CO2   out of the atmosphere. The so-called “biological pump” stores carbon in the deep sea, which is one way that biology influences global climate.

“It has been assumed that the amount of organic material that sinks to the sea floor would parallel that produced through photosynthesis near the sea surface,” said Mix, who is in OSU’s College of Earth, Ocean, and Atmospheric Sciences. “Surprisingly, our study found that even as plant growth decreased, past warming actually enhanced the biological export of carbon to the deep sea, at least in the northeast Pacific.”

Lead author Cristina Lopes, a visiting scientist at Oregon State who is based at the Instituto Português do Mar e da Atmosfera (IPMA, Portuguese Sea and Atmosphere Institute) in Portugal, and colleague Michal Kucera at the Center for Marine Environmental Sciences at Germany’s University of Bremen, calculated the productivity of marine plankton during the last major global warming event leading to the end of the last ice age. They did so by examining fossil diatoms buried in sediment off the coast of Oregon.

A breakthrough came from applying neural network methods now used by financial and insurance industries. “Inspired by brain research, we adapted these machine learning methods to analyze the fossil record for a new view of how the ocean works,” Kucera said.

The researchers found that during the ice age, the carbon trapped in plankton off Oregon was mostly recycled rather than exported to the deep ocean. As the ice age waned and the ocean warmed, plant growth decreased while carbon export increased.

“This counterintuitive effect was driven by a shift in ecosystems to one dominated by large diatoms,” Lopes said. “Those diatoms bloomed, then sank fast when they died.”

The researchers say their findings don’t necessarily mean that the ocean can continue to absorb increasing amounts of CO2   indefinitely, but that computer models of the ocean’s carbon cycle will need to take into account that plant productivity and carbon export are not always linked.

Evidence that export of carbon to the deep sea increases in some regions during long-term warming may help to slow down global climate change, but it may make some other impacts worse, the researchers point out. For example, as the extra sinking organic matter decomposes, it consumes oxygen dissolved in seawater – and loss of oxygen in the ocean is a growing concern.

Low-oxygen “dead zones” have appeared off the coast of Oregon several times in recent years.

“If these connections between warming and enhanced carbon export that we’ve found in past climate changes are triggered in the future, we can expect those marine dead zones to show up more frequently,” Mix said.

Media Contact: 

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

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Lionfish analysis reveals most vulnerable prey as invasion continues

CORVALLIS, Ore. – If you live in lionfish territory in the Atlantic Ocean, the last thing you want to be is a small fish with a long, skinny body, resting by yourself at night, near the bottom of the seafloor.

If so, your chances of being gobbled up by a lionfish increase by about 200 times.

Findings of a study on lionfish predation behavior, which may also apply to some other fish and animal species, have shed some new light on which types of fish are most likely to face attack by this invasive predator, which has disrupted ecosystems in much of the Caribbean Sea and parts of the Atlantic Ocean.

The research has been published in the Journal of Animal Ecology by scientists from Oregon State University and Simon Fraser University. It used the study of lionfish to gain broader insights into how predators select their prey, and developed a new method for predicting diet selection across various prey assemblages.

“With species now moving all over the world in both marine and terrestrial systems, we need to know who will eat whom when species encounter each other for the first time,” said Stephanie Green, the David H. Smith Conservation Research Fellow in the OSU College of Science, who has done extensive studies of lionfish.

“Normally, predator-prey experiments take a lot of effort and time,” Green said. “But there are mathematical techniques that can help us better understand what is happening when we observe animals hunting in the wild, and why some species get eaten and others don’t.”

Green said that researchers want to identify common features across the animal kingdom that make some species more vulnerable than others.

“We’re playing catch-up on this,” she said. “However, with the case of species invasions, a much better understanding of which native species are at risk can help us target management intervention. This could help avoid extirpations and, in the worst-case scenario, more outright extinctions.”

This study is one of the first to identify general traits of prey that predict vulnerability to predation, and examine diet selection at different spatial scales. Some of the findings may be relevant to other invasive species problems, such as expansion of the Burmese python in the Florida Everglades and the spread of Asian tiger prawn into the Gulf of Mexico.

The study also showed that although lionfish have a voracious appetite and will eat almost any fish smaller than they are, they do have their favorites.

They find it easier to stalk and attack solitary fish, rather than those in schools. They like to hunt at dusk, near the bottom, and for some reason tend to avoid fish that clean off parasites from other fish species that are common in a marine environment.

“Fish that clean parasites off of other fish appear to be avoided by lionfish,” Green said. “Those that don’t will be much harder hit.”

Having all the traits that make them vulnerable, for instance, raises a serious question about the ability of some species to survive the lionfish invasion, such as the Exuma Goby, a small fish native to one area of The Bahamas. It has many traits lionfish prefer.

OSU researchers are working with the International Union for Conservation of Nature to help identify some of the species and problem areas most at risk of extinction from the lionfish invasion, and where control of the invaders should be prioritized.

Lionfish are now established on coral reefs across the western Atlantic Ocean, Caribbean Sea and Gulf of Mexico, and the invasion continues to spread while reef biodiversity and biomass rapidly declines. The high rate of fish mortality also poses an additional threat to coral reefs themselves, which can become covered with algae if enough fish are not present to eat the algae and keep it under control.

The research was supported by the Natural Science and Engineering Research Council of Canada and the David H. Smith Conservation Research Program.

Media Contact: 

Stephanie Green, 778-808-0758

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Reef research
Stephanie Green

Hunting lionfish
Hunting lionfish

Hunting at dusk

Algae on coral reef
Algae-covered corals

“Picky Eaters,” a Podcast about species diet preferences, is online at: http://bit.ly/1vpMcAA

Biomarker could provide early warning of kidney disease in cats

CORVALLIS, Ore. – Researchers from Oregon State University and other institutions have developed a new biomarker called “SDMA” that can provide earlier identification of chronic kidney disease in cats, which is one of the leading causes of their death.

A new test based on this biomarker, when commercialized, should help pet owners and their veterinarians watch for this problem through periodic checkups, and treat it with diet or other therapies to help add months or years to their pet’s life.

Special diets have been shown to slow the progression of this disease once it’s identified.

The findings were made in a controlled study of 32 healthy, but older cats, and have been published in The Veterinary Journal by researchers from OSU and IDEXX Laboratories. They demonstrated the efficacy of a biomarker that could form the basis for a new diagnostic test.

“Chronic kidney disease is common in geriatric cats and often causes their death,” said Jean Hall, a small animal medical expert and professor in the OSU College of Veterinary Medicine. “Damage from it is irreversible, but this is an important advance, in that we should be able to identify the problem earlier and use special diets to slow the disease.”

Many of these same health issues also relate to older dogs, and in continued research scientists believe they may make similar findings.

Renal decline is normal in most cats, experts say, as they reach 12-18 years of age, and along with issues such as cancer and gastrointestinal disease is one of the more common causes of death. But studies have shown that the problem can also be managed with special foods that reduce protein and phosphorus, while adding fish oil, antioxidants, L-carnitine and medium-chain triglycerides.

This biomarker was able to identify the onset of kidney disease in cats on average 17 months earlier than any existing approach, and in at least one case four years earlier. With special diets and care, some cats have lived several years after the disease was diagnosed.

The only existing test for the disease, which has been used for decades, is a blood test that checks creatinine levels, a marker of the breakdown of muscle protein. However, cats lose lean body mass as they age, so creatinine levels may be normal.  SDMA is not influenced by lean body mass and thus more accurately diagnoses the loss of kidney function, even if lean body mass has decreased.

The early symptoms of this disease are fairly non-specific, such as loss of appetite, weight loss, or vomiting.

The cats in this research were housed at the Science and Technology Center of Hill’s Pet Nutrition Inc.  The company provided data and samples for analysis in order to better understand the dietary needs of cats with early renal disease, and initiated the study to investigate how best to lengthen and enrich the lives of cats with the condition.

Media Contact: 

Jean Hall, 541-737-6537

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Aging cat
Aging cat

New technology may speed up, build awareness of landslide risks

CORVALLIS, Ore. – Engineers have created a new way to use lidar technology to identify and classify landslides on a landscape scale, which may revolutionize the understanding of landslides in the U.S. and reveal them to be far more common and hazardous than often understood.

The new, non-subjective technology, created by researchers at Oregon State University and George Mason University, can analyze and classify the landslide risk in an area of 50 or more square miles in about 30 minutes - a task that previously might have taken an expert several weeks to months. It can also identify risks common to a broad area rather than just an individual site.

And with such speed and precision, it reveals that some landslide-prone areas of the Pacific Northwest are literally covered by landslides from one time or another in history. The system is based on new ways to use light detecting and ranging, or lidar technology, that can seemingly strip away vegetation and other obstructions to show land features in their bare form.

“With lidar we can see areas that are 50-80 percent covered by landslide deposits,” said Michael Olsen, an expert in geomatics and the Eric HI and Janice Hoffman Faculty Scholar in the OSU College of Engineering. “It may turn out that there are 10-100 times more landslides in some places than we knew of before.

“We’ve always known landslides were a problem in the Pacific Northwest,” Olsen said. “Many people are just now beginning to realize how big the problem is.”

An outline of the new technology was recently published in Computers and Geosciences, a professional journal.

Oregon and Washington, especially in the Coast Range and Cascade Range, are already areas commonly known to have landslides, and as a result Oregon’s Department of Geology and Mineral Industries has become a national leader in mapping of them, Olsen said. But previous approaches are slow, and the new technology, called a Contour Connection Method, could radically speed up widespread mapping, and build both professional and public awareness of the issue.

Despite the prevalence and frequency of landslides, they are not generally covered by most homeowner insurance policies; coverage can be purchased separately, but most people don’t. And with increasing population growth, more and more people are moving into more remote locations, or building in scenic areas near the hills around cities where landslide risk might be high.

“A lot of people don’t think in geologic terms, so if they see a hill that’s been there for a long time, they assume there’s no risk,” said Ben Leshchinsky, a geotechnical engineer in the OSU College of Forestry. “And many times they don’t want to pay extra to have an expert assess landslide risks or do something that might interfere with their land development plans.”

Lidar is already a powerful tool, but the new system developed at OSU offers an automated way to improve the use of it, and could usher in a new era of landslide awareness, experts say. Information could be more routinely factored into road, bridge, land use, zoning, building and other decisions.

With this technology, a computer automatically looks for land features, such as suddenly steeper areas of soil, that might be evidence of a past landslide. It then searches the terrain for other features, such as a “toe” of soils at the base of the landslide. And in minutes it can make unbiased, science-based classifications of past landslides that consistently use the same criteria.

The technology was applied to the region surrounding the landslide of March, 2014, that killed 43 people near the small town of Oso, Washington. In about nine minutes it was able to analyze more than 2,200 acres and many prehistoric landslide features that are readily apparent in lidar images, in this region known for slope instability.

Eventually, adaptations of the technology might even allow for real-time monitoring of soil movement, the researchers said.

Media Contact: 

Michael Olsen, 541-737-9327

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Landslide detection

Landslide detection

Landslide map of region
Mapped landslide inventory

Oso landslide
Oso, Washington landslide

Virulent bacteria affecting oysters found to be a case of mistaken identity

CORVALLIS, Ore. -  The bacteria that helped cause the near-ruin of two large oyster hatcheries in the Pacific Northwest have been mistakenly identified for years, researchers say in a recent report.

In addition, the study shows that the bacteria now believed to have participated in that problem are even more widespread and deadly than the previous suspect.

Although the hatchery industry has largely recovered, primarily by better control of ocean water acidity that was also part of the problem, the bacterial pathogens remain a significant concern for wild oysters along the coast, researchers said.

For many years, it had been believed that the primary bacteria causing oyster larval death in the Pacific Northwest was Vibrio tubiashii. Now, scientists say that most, or possibly all of the bacterial problem was caused by a different pathogen, Vibrio coralliilyticus, a close cousin that’s now known to be even more virulent to Pacific oysters.

The findings were published in Applied and Environmental Microbiology, by researchers from the College of Veterinary Medicine at Oregon State University, the U.S. Department of Agriculture, and Rutgers University. The research was supported by the USDA.

“These bacteria are very similar, they’re close cousins,” said Claudia Häse, an OSU associate professor and expert in microbial pathogenesis. “V. coralliilyticus was believed to primarily infect warm water corals and contributes to coral bleaching around the world. It shares some gene sequences with V. tubiashii, but when we finally were able to compare the entire genomes, it became apparent that most of what we’re dealing with in the Pacific Northwest is V. coralliilyticus.”

Scientists now say that V. coralliilyticus is not only far more widespread than previously believed, but that it can infect a variety of fish, shellfish and oysters, including rainbow trout and larval brine shrimp. And it appears to be the primary offender in bacterial attacks on Pacific Northwest oyster larvae.

OSU experts have developed a rapid diagnostic assay for this bacteria that is nearing commercialization, and it may help assess problems both in oyster and coral health, Häse said.

“Although we’ve largely addressed the problems the hatcheries face, these bacteria continue to pose threats to wild oysters,” Häse said. “And corals are still declining in many places, the Great Barrier Reef in Australia is dying at an alarming rate. Better diagnostics might help in all of these situations.”

In what’s now understood to be a problem with multiple causes, these pathogenic bacteria were involved in major crashes of oyster hatcheries, causing shortages in seed oysters for commercial producers. Dramatic losses were suffered in a Netarts Bay, Oregon, hatchery in 2005, and Washington hatcheries were also hard hit. Bacterial infection, water acidity, oxygen depletion and rising seawater temperatures are all believed to have been part of the problem.

By better monitoring and control of water acidity, which was one serious concern, hatcheries have been able to regain most of their productive capabilities. Wild oysters, however, continue to face the multiple pressures from rising acidity, pathogenic bacteria and other forces that have led to serious hatchery mortality.

Those problems have not been made any easier by the lack of funding for identification and studies of the bacteria that researchers now know to be causing infection.

In laboratory tests, strains of V. tubiashii did not show significant pathogenicity to Pacific oysters. V. coralliilyticus, by contrast, is highly infectious to both Pacific and Eastern oyster larvae, and perhaps other shellfish species.

“The Vibrio genus and many bacteria associated with it are a huge problem in fish and shellfish aquaculture, and we should be studying them more aggressively,” Häse said. “V. coralliilyticus, in particular, has a very powerful toxin delivery system, and vibrios are some of the smartest of all bacteria. They can smell, sense things and swim toward a host.”

It’s believed that increasing environmental stresses may make oysters and other marine life more vulnerable to these types of bacterial infection, researchers say.

Media Contact: 

Claudia Häse, 541-737-7001

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Oyster larvae
Oyster larvae

New advance in cryopreservation could change management of world blood supplies

CORVALLIS, Ore. – Engineers at Oregon State University have identified a method to rapidly prepare frozen red blood cells for transfusions, which may offer an important new way to manage the world’s blood supply.

It’s already possible to cryopreserve human red blood cells in the presence of 40 percent glycerol, but is rarely done because of the time-consuming process to thaw and remove the glycerol from the blood. This can take an hour or more and makes it logistically difficult to use frozen blood.

However, some initial experiments and computer modeling of a proposed new process suggest that this hour-long process can be reduced to as little as three minutes, using a membrane-based, microfluidic device. This could make it far more feasible to use frozen blood in emergency or time-constrained medical situations.

The findings were just reported in the journal Biomicrofluidics.

“Only a small fraction of our blood supply is now frozen, because it’s often impractical to wait so long when a transfusion is needed immediately,” said Adam Higgins, an expert in medical bioprocessing and associate professor in the OSU School of Chemical, Biological and Environmental Engineering.

“Because of that, our entire system depends on constantly balancing the use and supply of blood products that can only last six weeks or less with refrigeration,” he said. “This is difficult, and can lead to loss of outdated blood, periodic shortages, and other inefficiencies that could be solved with the use of frozen blood.”

Researchers in the OSU College of Engineering, however, have become national leaders in the science of microfluidics, which uses microchannel-based approaches to processing fluids for various purposes, ranging from more efficient heat pumps to innovative methods for kidney dialysis.

In the case of frozen blood, extremely tiny microchannel plates and membranes could be used to precisely control removal of glycerol from blood at a time scale of seconds. This would allow much more rapid thawing of frozen blood, which isn’t possible using the centrifugal cell washers that have been around for decades and are the only other way to remove glycerol from the blood.

The new approach should work, OSU experts say.

“Our results pave the way for development of a clinical device for ultra-rapid glycerol extraction, which would greatly improve the logistics of blood banking,” the researchers wrote in their report.

According to their report, each year more than 100 million blood donations are collected worldwide, enabling millions of life-saving transfusions. But refrigerated blood has a short shelf life, and some recent studies even suggest that “older” blood being used within what’s believed to be an acceptable refrigeration period may be linked to severe complications.

Cryopreservation could extend the shelf life of blood from weeks to years; dramatically smooth out the undependable supplies of blood; and according to recent research, produce cryopreserved red blood cells that have superior biochemical and tissue oxygenation capabilities compared to refrigerated red blood cells.

This research has been supported by a CAREER Award from the National Science Foundation.

In continued studies, researchers said they hope to create working prototypes of the needed technology for further development and testing of the concept. An optimized process may also be even faster than the three minutes now being predicted, they said.

Media Contact: 

Adam Higgins, 541-737-4600

“Eyespots” in butterflies shown to distract predatory attack

CORVALLIS, Ore. – Research has demonstrated with some of the first experimental evidence that coloration or patterns can be used to “deflect” attacks from predators, protecting an animal’s most vulnerable parts from the predators most likely to attack them.

The study, published today in Proceedings of the Royal Society B, in fact shows that one species of butterfly uses its “eyespots” not only for protection, but varies the color and intensity of them by season as the types of predators change.

The findings were made by researchers from Oregon State University, Yale University and four other institutions.

“Eyespots are conspicuous, they draw your attention and are thought to be used by many animal species to avoid death or attack, by either startling or confusing the predator,” said Katy Prudic, lead author on the study and a researcher with the Department of Integrative Biology in the College of Science at Oregon State University. “Many insects have eyespots, which suggests they are an important adaptation.”

The butterfly species studied, Bycyclus anyana, produces about five generations a year during both wet and dry seasons in its native habitat. Through a process scientists call “phenotypic plasticity,” the same genes can produce two different eyespot patterns in the adults. Warm temperatures of the wet season create large and bright eyespots, while cool temperatures common in the dry season produce dull and small eyespots.

During the wet season, the large eyespots make a colorful target for attack, conceptually similar to a matador waving a cape that distracts a charging bull into attacking the wrong thing.

In this season, predatory insects such as the praying mantids are their greatest enemy, and the showy eyespots on the wings led the mantids to attack the butterfly wings rather than the more vulnerable body or head. The wings are badly damaged, but the insect can escape and live to reproduce.

During the dry season, most insect predators are dead but birds abound. For birds, the smaller, dull eyespots make the butterfly more difficult to detect and consume.

“Having the right type of eyespot in the right season allowed the butterflies to live long enough to lay eggs and have more offspring in the next generation,” Prudic said. “With the wrong eyespot at the wrong time, they were quickly annihilated by the mantids.”

Color pattern has always been a form of protection against predators in nature, Prudic said. It can take the form of camouflage, mimicry, delaying or redirecting attacks. But studies that observed and hypothesized about such changes have been difficult to document in controlled experiments such as this.

Eyespots are one of nature’s favorite forms of misdirection, shared by fish, frogs, birds, and many insects. Aside from deflecting attack, they can also be used as a “startle” mechanism, being flashed just long enough to delay attack briefly and allow a species to escape. Researchers also believe eyespots can play a role in sexual attraction and mate selection.

This research was supported by the Yale Institute for Biospheric Studies, the Donnelley family and the Singapore Ministry of Education.

Media Contact: 

Kathleen Prudic, 541-737-5736

Multimedia Downloads

Wet season
Wet season

Dry season
Dry season

Butterfly eyespots YouTube video http://youtu.be/0d9fzaxjvYs

Mantids attack YouTube video http://youtu.be/BObK3vzXf7g