Can soil bacteria clean up our toxic messes?

Thousands of sites across the US are contaminated with chemical solvents that have been used for decades in industrial processes. These solvents can leach into groundwater and create plumes up to several miles long. 1,4-dioxane, a probable human carcinogen, is often present in groundwater contaminant plumes because of its historical use in degreasing heavy machinery, but it’s also present in trace amounts in products as varied as laundry detergents, deicing agents, cosmetics, and even in food.

There’s good news and bad news here: The Resource Conservation and Recovery Act, enacted in 1980, established laws for the management and disposal of hazardous wastes, meaning new releases to the environment have diminished considerably. Decontamination of chlorinated solvents often involves pumping groundwater to the surface and removing the contamination through volatilization or adsorption. However, this process is expensive, time- and energy-consuming, and ineffective at removing some chemicals, like water-soluble 1,4-dioxane.

Some jobs require the help of friends. In this case, for Hannah Rolston, a fifth-year PhD student in the Department of Environmental Engineering working with Dr. Lewis Semprini, these friends are soil bacteria that are able to naturally degrade this carcinogen. Bioremediation, or the practice of putting these bacteria to work to degrade contaminants, offers some hope in cases like these. Sometimes they can degrade certain pollutants all by themselves (called natural attenuation), but when you’re dealing with carcinogens in areas with people nearby, you want to use an engineered approach to make sure this process goes as quickly and efficiently as possible.

Hannah explained to us that not all compounds are easily degraded by bacteria, and even though some will consume 1,4-dioxane as food, environmental concentrations are not enough to sustain their growth (though remain harmful to humans). To work around this, she has been using a strategy called cometabolism. This involves adding a different carbon source into the groundwater plume for the microbes to eat–ideally, one that will cause the bacteria to produce enzymes that not only degrade the food source, but the 1,4-dioxane as well. This can be tricky, and not only in an engineering sense: you need to know enough microbial metabolism to be sure they’re not converting the hazardous compound into something even worse.

Hannah collecting groundwater samples from test wells at the OSU motor pool.

Using soil samples from two contaminated sites in Colorado and California, Hannah and the Semprini group are using isobutane (yes, the same gas you use for your camp stove) to nourish the native microbial communities so that they produce a type of enzyme called a monooxygenase. She has observed the 1,4-dioxane levels decrease in these enrichments. Preliminary work shows the bacteria convert 1,4-dioxane all the way to carbon dioxide–completely benign compared to what we started with.

Hannah began her undergraduate at Seattle University as an international studies major interested in a career in diplomacy. Feeling her first year of humanities classes provided her a wide breadth of knowledge but didn’t give her applicable skills, she transferred to environmental engineering, where she became interested in groundwater and hazardous waste remediation. After graduation, she worked for the US Army Environmental Command, working with army installations across the country to comply with environmental regulations.. When the spreadsheets and desk work didn’t quite live up to its expectations, she knew it was time to seek out graduate programs where she could put her engineering background and interest in hazardous waste remediation to work.

When she’s not tricking microbes into consuming carcinogenic contaminants, Hannah can be found road biking and doing ceramics at the OSU craft center. She is also involved in the OSU Chemical, Biological, and Environmental Engineering Graduate Student Association and the OMSI Science Communication Fellowship program. To hear more about her research and journey to graduate school, tune in to Inspiration Dissemination Sunday August 26th at 7pm on 88.7 FM, or stream the show live.

The Evolving Views of Plastic Pollution

Oceans cover more than 70% of the Earth’s surface and some studies suggest we still have over 91% of marine species that await discovery. Even as far back as 2010 some NASA scientists admit we knew more about the surface of Mars than we did about the bottom of our own oceans! Despite the fact we may not know everything about our oceans just yet, one thing is certain: plastics are becoming part of ecosystems that have never experienced it and we’re beginning to understand its massive impact. One estimate suggests that even if you had 100 ships towing for 10 hours a day, with 200 meters of netting and perfectly capturing every large and tiny piece of plastic, we could only clean up 2% of the Great Pacific Garbage Patch every year. It would take 50 years to clean everything up, assuming we magically stopped using plastics on Earth. As one Nature research article suggests, the problems lies mostly with local municipalities; but that means with targeted local action, individuals can make a real difference and limit how much plastic makes it to our oceans. So you may be thinking “let’s tell all our friends these plastic facts and then everyone will stop using plastic, right?”. Not so fast, unfortunately a host of studies show just informing people about the scope of the problem doesn’t always make them change their behavior to ameliorate the problem in question.

Katy getting a seal kiss from Boots the harbor seal at the Oregon Coast Aquarium

Our guest this evening is Katy Nalven, a 2nd year Masters student in the Marine Resources Management program, who is using a community based social marketing approach to ask people not only IF they know about the problem of plastics in oceans, but she also seeks to understand how people think about this problem and what could be individual hurdles to decreasing plastic usage. Using a survey based approach administered at the Oregon Coast Aquarium, Katy plans to examine a few specific communities of interest to identify how the views around plastic usage from Aquarium visitors and local community members may differ and hopefully where they overlap.

This community based social marketing approach has many steps, but it’s proven more effective in changing behaviors for beneficial outcomes rather than just mass media information campaigns by themselves. By identifying a target goal for a community of interest you can tailor educational material that will have the greatest chance of success. For example, if your goal is to decrease plastic usage for coastal communities in Oregon, you may find that a common behavior in the community you can target to have the greatest impact such as bringing your own mug to coffee shops for a discount, or automatically saying “no straw please” whenever going out to eat. Katy is beginning to pin down how these Oregon coast communities view plastic usage with the hope that a future student can begin implementing her recommended marketing strategies to change behaviors for a more positive ocean health outlook.

Hugs from Cleo, the Giant Pacific Octopus, at the Oregon Coast Aquarium

Katy grew up in the landlocked state of Arizona constantly curious about animals, but on a childhood visit to SeaWorld San Diego she became exposed to the wonders of the ocean and was wonderstruck by a close call with a walrus. Near the end of a Biology degree in her undergraduate years, simultaneously competing as an NAIA Soccer player for Lyons College, Katy was looking for career options and with a glimpse of her stuffed walrus she got at the San Diego Zoo, she decided to look at Alaska for jobs. After a few summers being a whale watching guide in Juneau, an animal handling internship in Florida, and then another internship in Hawaii Katy decided she wanted to formally revisit her science roots but with a public policy perspective. Oregon State University’s Marine Resource Management Program was the perfect fit. In fact, once she was able to connect with her advisor, Dr. Kerry Carlin-Morgan who is also the Education Director for the Oregon Coast Aquarium, Katy knew this was the perfect step for her career.

Meeting Jack Johnson at the 6th International Marine Debris Conference. He and his wife are the founders of the Kokua Hawaii Foundation whose mission is to “provide students with experiences that will enhance their appreciation for and understanding of their environment so they will be lifelong stewards of the earth.”

 

 

Be sure to tune in to Katy’s interview Sunday August 19th at 7PM on 88.7FM, or listen live, to learn more about her findings about how we view plastic pollution, and how we can potentially make local changes to help the global ecosystem.

Mobility is critical to social and cognitive development in children

Learning to crawl and walk affords children opportunities to explore their world. As such, early childhood mobility is intertwined with other formative childhood milestones, such as motor skill development and learning to negotiate social encounters. Disabled children who may have difficulty reaching mobility milestones, are thus at risk for missing out on opportunities for play and exploration that are critical to cognitive, social, and motor skill development. Samantha Ross, a PhD student in the Kinesiology, Adapted Physical Activity program within the College of Public Health and Human Sciences at Oregon State University, asks the question: how can we support the movement experiences of children with mobility disabilities to ensure they have equitable access to play, exploration and social encounters?

The experience of movement Ride-on cars are modified, child-sized, battery powered vehicles designed to support children with disabilities during play. The ride-on car is equipped with a large button to initiate movement, as well as structural modifications to enhance body support. As part of her research, Samantha observes children with and without disabilities participating in an inclusive play group. She monitors changes in the behavior of individual children, and video analysis helps her to track their distance traveled while using a ride-on car. Factors including whether the child initiated their own movement, if movement included interaction with a peer, or was motivated by a toy, all contribute to a child’s experience of mobility. The ride-on car facilitates the initiation of new relationships among children, noticeably reducing the barrier between children with and without disabilities and promoting equitable play experiences.

For more information about ride-on cars and to watch videos of the cars in action, visit the GoBabyGo website: https://health.oregonstate.edu/gobabygo

The impact of impaired mobility is nuanced Nearly thirty years of research has indicated that young children can benefit from powered mobility devices. However, the field is dominated by the medical perspective of reducing disability. In recent years, a major push from disability groups has emphasized the importance of community and social interactions in enhancing the well-being of children with disabilities. Mobility cannot be distilled down to simply moving from point A to point B, rather the self-perceived experience of movement and how movement facilitates encounters with people and objects is integral to children’s feelings of well-being. It is important for children to feel valued for their contribution. Samantha’s goal is to facilitate a social environment that enhances the well-being and development of children with disabilities, thereby promoting equitable access to a healthy and active childhood.

Following graduate school, Samantha would like to continue her involvement in research at one of the University Centers of Excellence in Developmental Disabilities, representing a partnership between state, federal, academic, and disability communities. Samantha explains, “We need to hear from people with disabilities – we need everyone at the table for the system to work.” These centers provide the interface between policy and research, where priorities are weighed and decisions are made. Often headquartered at medical schools, the centers raise awareness and help train future healthcare professionals. Samantha would love to be involved in this discussion.

Join us on Sunday, August 5th at 7pm on KBVR Corvallis 88.7 FM or stream live to hear more about Samantha’s research. We will discuss other aspects of her research, as well, including her investigation of national surveillance reports, which provide insight about whether children’s service needs are being met, and how to identify children who could benefit from mobility assistive devices.

How do bone cancer cells become resistant to chemotherapy?

Limited treatments for bone cancer Bone cancer is a devastating and poorly understood disease with few available treatment options in humans. The disease disproportionately impacts young adults and children, and treatment still often includes amputation of the affected limb. Relapse within one year is common. Dogs can also spontaneously develop bone cancer, which makes them a suitable model for comparative oncology: insights about disease progression in dogs can yield insights about the disease in humans.

Animal models – one size does not fit all The difficulty of establishing a robust animal model has impeded scientists’ ability to study bone cancer rigorously. For example, although mice are commonly used to study human disease, they do not develop bone cancer spontaneously. Invasive tumor tissue grafts are required to study the disease in mice, which adds confounding variables to the results – it is not necessarily clear if an observed effect is the result of the tumor or the grafting procedure.

Understanding how chemotherapy resistance develops As a 2nd year Master’s student in the College of Veterinary Medicine, Marcus Weinman is working towards understanding how bone cancer tumors adapt and acquire resistance to chemotherapy. He has been developing canine osteosarcoma cell lines to study disease progression, which entails exposing cells to chemotherapy until they become resistant. Using a variety of molecular biology techniques, Marcus investigates how cells acquire resistance, and whether specific molecules or groups of molecules are more active or less active as resistance develops. The goal is to identify possible targets within the cell that might be sensitive to therapeutic intervention.  

Complexity of bone cancer cells Cells contain exosomes – small packages containing a diverse mix of molecules – that participate in signaling and transfer of molecules between cells. These compact cellular packages are being investigated for their role in the development of resistance. These tumor cells are also endocrine tumors – they express hormones normally found in other tissues, such as the brain and the gut – which adds a layer of physiology to the already-complex nature of cancer.

Why cancer research? Originally from Denver, Colorado, Marcus knew he wanted to attend OSU to pursue research opportunities. He completed his undergraduate studies at OSU, and attributes part of his desire to attend OSU to a deep family connection to Corvallis – his grandfather was a professor at OSU!

After completing his Master’s, Marcus plans to attend med school, with the eventual goal of becoming an oncologist, while maintaining his connection to research. He emphasizes how the teaching component of medicine is a motivating factor in his desire to become a physician. As a clinician, he would like to teach patients how to take care of themselves by integrating educational and interpersonal aspects of medicine.

Join us on Sunday, July 29th at 7pm on KBVR Corvallis 88.7 FM or stream live to hear more from Marcus about his research and experience as a graduate student at OSU.

 

Don’t just dream big, dream bigger

If you’ve purchased a device with a display (e.g. television, computer, mobile phone, handheld game console) in the last couple decades you may be familiar with at least some of the following acronyms: LCD, LED, OLED, Quantum LED – no, I did not make that up. Personally, I find it all a bit overwhelming and difficult to keep up with, as the evolution of displays is so rapidly changing. But until the display replicates an image that is indistinguishable from what we see in nature, there will always be a desire to make the picture more lifelike. The limiting factor of making displays appear realistic is the number of colors used to make the image. Currently, not all color wavelengths are used.

Akash conducting research on nanoparticles.

This week’s guest, Akash Kannegulla studies how light interacts with nanostructure metals for applications to advance display technology, as well as biosensing. Akash is a PhD candidate in the Electrical Engineering and Computer Science program with a focus in Materials and Devices in the Cheng Lab. Exploiting the physical and chemical properties of nanoparticles, Akash is able to work toward the advancement of display and biosensing technologies.

When shining light on metals, electrons and photons interact and oscillate to create a surface plasma, or “electron cloud”. Under specific conditions, when fluorescent dye is excited with UV light on the surface plasma, electrons move to higher atomic levels. When the electrons return to lower atomic levels, energy is released in the form of light. This light is 10-100X brighter than it would be without the use of fluorescent dyes. With this light magnification, less voltage is used to produce a comparable brightness level. This has two main benefits; first consumer products can use less energy to produce the same visual experience, so we can significantly decrease our carbon footprint. Second, these unique conditions can be amplified at the nano-scale, which means smaller pixels and more colors that can be produced so our TV screens will look more and more like the real world around us. These new advancements at the nano-scale have extremely tight tolerances in order for it to work; however, in this case, not working can also provide some incredible information.

This technology can be applied in biosensing to detect mismatches in DNA sequences. A ‘mismatch’ in a DNA sequence has a slightly different chemical bond, the distance between the atoms is ever so slightly different than what is expected, but that tiny difference can be detected by how intense the light is – again the nanoscale is frustratingly finnicky at how precise the conditions must be in order to get the expected response – in this case light intensity. So when we get a ‘dim’ spot, it can be indicative of a mismatched DNA segment! Akash predicts that in a just a few years, this nanotechnology will make single nucleic acid differentiations detectable on with sensing technology on a small chip or using a phone camera, rather than a machine half the size of MINI Cooper.

Akash, the entrepreneur, with his winning certificate for the WIN Shark Tank 2018 competition.

In addition to Akash’s research, he has spent a significant portion of his graduate career investing in an award-winning start-up company, Wisedoc.This project was inspired by the frustration Akash felt, and probably all graduate students and researchers, when trying to publish his own work and found himself spending too much time formatting and re-formatting rather than conducting research. By using Wisedoc, you can input your article content into the program and select a journal of interest. The program will then format your content to the journal’s specifications, which are approved by the respective journal’s editors to make publishing academic articles seamless. If you want to submit to another journal, it only takes a click to update the formatting. Follow this link for a short video on how Wisedoc works. And for those of us with dissertations to format, no worries – Wisedoc will have an option for that, too. Akash notes that Wisedoc would not have been possible without the help of OSU’s Advantage Accelerator program, which guides students, faculty, staff, as well as the broader community through the start-up process. Akash’s team has won the Willamette Innovators Network 2018 Shark Tank competition, which earned them an entry into the Willamette Angel Conference, where Wisedoc won the Speed Pitch competition. If you are as eager as I am to checkout Wisedoc, the launch is only a few months away in December 2018!

The soon-to-be Dr. Akash Kannegulla – his defense is only a month away – is the first person in decades from his small town at the outskirts of Hyberabad, India, to attend graduate school. Akash’s start in engineering was inspired by his uncle, an achieved instrumentation scientist. Not knowing where to start, Akash adopted his uncle’s career choice as an engineer, but took the time to thoroughly explore his specialty options while an undergraduate. A robotics workshop at his undergraduate institution, Amirta School of Engineering in Bangalore, India, sparked an interest in Akash due to the hands-on nature of the science. Akash explored undergraduate research opportunities in the United States landing on a Nano Undergraduate Research Fellowship from University of Notre Dame. During the summer of 2013, Akash studied photo induced re-configurable THz circuits and devices under the guidance of Dr. Larry Cheng and Dr. Lei Liu. Remarkably, Akash conducted research resulting in a publication after only participating in this four-week fellowship. After graduating with the Bachelor of Technology in Instrumentation, Akash decided to come to Oregon State University to continue working with Dr. Cheng as a PhD student.

After defending, Akash will be working at Intel Hillsboro, as well as preparing for the launch of Wisedoc in December. And if that doesn’t sound like enough to keep him busy, Akash has plans for two more start-ups in the works.

Join us on Sunday, July 22 at 7 PM on KBVR Corvallis 88.7 FM or stream live to learn more about Akash’s nanotechnology research, start-up company, and to get inspired by this go-getter.

 

The Mold That Keeps On Giving

All around us, plants, fungi, and bacteria are waging chemical warfare against one another to deter grazing, prevent against infection, or reduce the viability of competitor species. Us humans benefit from this. We use many of these compounds, called secondary metabolites, as antibiotics, medicines, painkillers, toxins, pigments, food additives, and more. We are nowhere close to finding all of these potentially useful compounds, particularly in marine environments where organisms can make very different types of chemicals. Could something as ordinary as a fungus from the sea provide us with the next big cancer breakthrough?

Paige Mandelare with one of the many marine bacteria she works with

Paige Mandelare thinks so. As a fourth-year PhD student working for Dr. Sandra Loesgen in OSU’s Chemistry department, she has extracted and characterized a class of secondary metabolites from a marine fungus, Aspergillus alliaceus, isolated from the tissues of an algae in the Mediterranean Sea. After growing the fungus in the laboratory and preparing an extract from it, she tested the extract on colon cancer and melanoma cell lines. It turned out to be cytotoxic to these cancer cells. Further purification of this mixture revealed three very similar forms of these new compounds they called allianthrones. Once Paige and her research group narrowed down their structures, they published their findings in the Journal of Natural Products.

Next, she grew the fungus on a different salt media, replacing bromine for chlorine. This forced the fungus to produce brominated allianthrones, which have a slightly different activity than the original chlorinated ones. Her lab then sent two of these compounds to the National Cancer Institute, where they were tested on 60 cell lines and found to work most effectively on breast cancers.

The recent publication of Paige in her story of the allianthrones from this marine-derived fungus, Aspergillus alliaceus.Like many organisms that produce them, this wonder mold only makes secondary metabolites when it has to. By stressing it with several different types of media in the lab, Paige is using a technique called metabolomics to see what other useful compounds it could produce. This will also give insight into how the fungus can be engineered to produce particular compounds of interest.

A native Rhode Islander who moved to Florida at the age of ten, Paige has always been fascinated with the ocean and as a child dreamed of becoming a marine biologist and working with marine mammals. She studied biology with a pre-med track as an undergraduate at the University of North Florida before becoming fascinated with chemistry. Not only did this allow her to better appreciate her father’s chemistry PhD better, she joined a natural products research lab where she first learned to conduct fungal chemical assays. Instead of placing her on a pre-med career path, her mentors in the UNF Chemistry department fostered her interest in natural products and quickly put her in touch with Dr. Loesgen here at OSU.

Paige enjoying her time at the Oregon Coast, when she is not in the research lab

After finishing her PhD, Paige hopes to move back east to pursue a career in industry at a pharmaceutical company or startup. In the meantime, when she’s not discovering anticancer agents from marine fungi, she participates in a master swimming class for OSU faculty, trains for triathlons, and is an avid baker.

To hear more about Paige and her research, tune in to KBVR Corvallis 88.7 FM this Sunday July 15th at 7 pm. You can also stream the live interview at kbvr.com/listen, or find it on our podcast next week on Apple Podcasts.

Stream ecosystems and a changing climate

Examining the effect of climate change on stream ecosystems

Oak Creek near McDonald Dunn research lab. The salamander and trout in the experiments were collected along this stretch of creek.

As a first year Master’s student in the lab of Ivan Arismendi, Francisco Pickens studies how the changing, warming climate impacts animals inhabiting stream ecosystems. A major component of stream ecosystem health is rainfall. In examining and predicting the effects of climate change on rainfall, it is important to consider not only the amount of rainfall, but also the timing of rainfall. Although a stream may receive a consistent amount of rain, the duration of the rainy season is projected to shrink, leading to higher flows earlier in the year and a shift in the timing of the lowest water depth. Currently, low flow and peak summer temperature are separated by time. With the shortening and early arrival of the rainy season, it is more likely that low flow and peak summer temperature will coincide.

A curious trout in one of the experimental tanks.

Francisco is trying to determine how the convergence of these two events will impact the animals inhabiting streams. This is an important question because the animals found in streams are ectothermic, meaning that they rely on their surrounding environment to regulate their body temperature. Synchronization of the peak summer temperature with the lowest level of water flow could raise the temperature of the water, profoundly impacting the physiology of the animals living in these streams.

 

 

How to study animals in stream ecosystems?

Salamander in its terrestrial stage.

Using a simulated stream environment in a controlled lab setting, Francisco studies how temperature and low water depth impact the physiology and behavior of two abundant stream species – cutthroat trout and the pacific giant salamander. Francisco controls the water temperature and depth, with depth serving as a proxy for stream water level.

Blood glucose level serves as the experimental readout for assessing physiological stress because elevated blood glucose is an indicator of stress. Francisco also studies the animals’ behavior in response to changing conditions. Increased speed, distance traveled, and aggressiveness are all indicators of stress. Francisco analyzes their behavior by tracking their movement through video. Manual frame-by-frame video analysis is time consuming for a single researcher, but lends itself well to automation by computer. Francisco is in the process of implementing a computer vision-based tool to track the animals’ movement automatically.

The crew that assisted in helping collect the animals: From left to right: Chris Flora (undergraduate), Lauren Zatkos (Master’s student), Ivan Arismendi (PI).

Why OSU?

Originally from a small town in Washington state, Francisco grew up in a logging community near the woods. He knew he wanted to pursue a career involving wild animals and fishing, with the opportunity to work outside. Francisco came to OSU’s Department of Fisheries and Wildlife for his undergraduate studies. As an undergrad, Francisco had the opportunity to explore research through the NSF REU program while working on a project related to algae in the lab of Brooke Penaluna. After he finishes his Master’s degree at OSU, Francisco would like to continue working as a data scientist in a federal or state agency.

Tune in on Sunday, June 24th at 7pm PST on KBVR Corvallis 88.7 FM, or listen live at kbvr.com/listen.  Also, check us out on Apple Podcasts!

Crabby and Stressed Out: Ocean Acidification and the Dungeness Crab

One of the many consequences associated with climate change is ocean acidification. This process occurs when high atmospheric carbon dioxide dissolves into the ocean lowering ocean pH. Concern about ocean acidification has increased recently with the majority of scientific publications about ocean acidification being released in the last 5 years. Despite this uptick in attention, much is still unknown about the effects of ocean acidification on marine organisms.

Close-up of a Dungeness crab megalopae

Our guest this week, Hannah Gossner, a second year Master’s student in the Marine Resource Management Program, is investigating the physiological effects of ocean acidification on Dungeness crab (Metacarcinus magister) with the help of advisor Francis Chan. Most folks in Oregon recognize the Dungeness crab as a critter than ends up on their plate. Dungeness crab harvest is a multimillion dollar industry because of its culinary use, but Dungeness crab also play an important role in the ocean ecosystem. Due to their prevalence and life cycle, they are important both as scavengers and as a food source to other animals.

Hannah pulling seawater samples from a CTD Carrousel on the R/V Oceanus off the coast of Oregon

To study the effect of ocean acidification on Dungeness crab, Hannah simulates a variety of ocean conditions in sealed chamber where she can control oxygen and carbon dioxide levels. Then by measuring the respiration of an individual crab she can better understand the organism’s stress response to a range of oxygen and carbon dioxide ratios. Hannah hopes that her work will provide a template for measuring the tolerance of other animals to changes in ocean chemistry. She is also interested in the interplay between science, management, and policy, and plans to share her results with local managers and decision makers.

Hannah working the night shift on the R/V Oceanus

Growing up in Connecticut, Hannah spent a lot of time on the water in her dad’s boat, and developed an interest in marine science. Hannah majored in Marine Science at Boston University where she participated in a research project which used stable isotope analysis to monitor changes in food webs involving ctenophores and forage fish. Hannah also did a SEA Semester (not to be confused with a Semester at Sea) where she worked on a boat and studied sustainability in Polynesian island cultures and ecosystems.  Hannah knew early on that she wanted to go to graduate school, and after a brief adventure monitoring coral reefs off the coast of Africa, she secured her current position at Oregon State.

Tune in Sunday June, 17 at 7 pm PST to learn more about Hannah’s research and journey to graduate school. Not a local listener? Stream the show live or catch the episode on our podcast.

Hannah enjoying her favorite past time, diving!

Ocean sediment cores provide a glimpse into deep time

Theresa on a recent cruise on the Oceanus.
Photo credit: Natasha Christman.

First year CEOAS PhD student Theresa Fritz-Endres investigates how the productivity of the ocean in the equatorial Pacific has changed in the last 20,000 years since the time of the last glacial maximum. This was the last time large ice sheets blanketed much of North America, northern Europe, and Asia. She investigates this change by examining the elemental composition of foraminifera (or ‘forams’ for short) shells obtained from sediment cores extracted from the ocean floor. Forams are single-celled protists with shells, and they serve as a proxy for ocean productivity, or organic matter, because they incorporate the elements that are present in the ocean water into their shells. Foram shell composition provides information about what the composition of the ocean was like at the point in time when the foram was alive. This is an important area of study for learning about the climate of the past, but also for understanding how the changing climate of today might transform ocean productivity. Because live forams can be found in ocean water today, it is possible to assess how the chemistry of seawater is currently being incorporated into their shells. This provides a useful comparison for how ocean chemistry has changed over time. Theresa is trying to answer the question, “was ocean productivity different than it is now?”

Examples of forams. For more pictures and information, visit the blog of Theresa’s PI, Dr. Jennifer Fehrenbacher: http://jenniferfehrenbacher.weebly.com/blog

Why study foram shells?

Foram shells are particularly useful for scientists because they preserve well and are found ubiquitously in ocean sediment, offering a consistent glimpse into the dynamic state of ocean chemistry. While living, forams float in or near the surface of the sea, and after they die, they sink to the bottom of the sea floor. The accumulating foram shells serve as an archive of how ocean conditions have changed, like how tree rings reflect the environmental conditions of the past.

Obtaining and analyzing sediment cores

Obtaining these records requires drilling cores (up to 1000 m!) into deep sea sediments, work that is carried out by an international consortium of scientists aboard large ocean research vessels. These cores span a time frame of 800 million years, which is the oldest continuous record of ocean chemistry. Each slice of the core represents a snapshot of time, with each centimeter spanning 1,000 years of sediment accumulation. Theresa is using cores that reach a depth of a few meters below the surface of the ocean floor. These cores were drilled in the 1980s by a now-retired OSU ship and are housed at OSU.

Theresa on a recent cruise on the Oceanus, deploying a net to collect live forams. Photo credit: Natasha Christman.

The process of core analysis involves sampling a slice of the core, then washing the sediment (kind of like a pour over coffee) and looking at the remainder of larger-sized sediment under a powerful microscope to select foram species. The selected shells undergo elemental analysis using mass spectrometry. Vastly diverse shell shapes and patterns result in different elements and chemistries being incorporated into the shells. Coupled to the mass spectrometer is a laser that ablates through the foram shell, providing a more detailed view of the layers within the shell. This provides a snapshot of ocean conditions for the 4 weeks-or-so that the foram was alive. It also indicates how the foram responded to light changes from day to night.

Theresa is early in her PhD program, and in the next few years plans to do field work on the Oregon coast and on Catalina island off the coast of California. She also plans to undertake culturing experiments to further study the composition of the tiny foram specimens.

Why grad school at OSU?

Theresa completed her undergraduate degree at Queen’s University in Ontario, followed by completion of a Master’s degree at San Francisco State University. She was interested in pursuing paleo and climate studies after transformative classes in her undergrad. In between her undergraduate and Master’s studies she spent a year working at Mt. Evans in Colorado as part of the National Park Service and Student Conservation Association.

Theresa had already met her advisor, Dr. Jennifer Fehrenbacher, while completing her Master’s degree at SF State. Theresa knew she was interested in attending OSU for grad school for several reasons: to work with her advisor, and to have access to the core repository, research ships, and technical equipment available at OSU.

To hear more about Theresa’s research and her experience as a PhD student at OSU, tune in on Sunday, June 10th at 7pm on KBVR Corvallis 88.7 FM, or listen live at kbvr.com/listen.  Also, check us out on Apple Podcasts!

How high’s the water, flood model? Five feet high and risin’

Climate change and the resulting effects on communities and their infrastructure are notoriously difficult to model, yet the importance is not difficult to grasp. Infrastructure is designed to last for a certain amount of time, called its design life. The design life of a bridge is about 50 years; a building can be designed for 70 years. For coastal communities that have infrastructure designed to survive severe coastal flooding at the time of construction, what happens if the sea rises during its design life? That severe flooding can become more severe, and the bridge or building might fail.

Most designers and engineers don’t consider the effects of climate change in their designs because they are hard to model and involve much uncertainty.

Kai at Wolf Rock in Oregon.

In comes Kai Parker, a 5th year PhD student in the Coastal Engineering program. Kai is including climate change and a host of other factors into his flood models: Waves, Tides, Storms, Atmospheric Forcing, Streamflow, and many others. He specifically models estuaries (including Coos and Tillamook Bay, Oregon and Grays Harbor, Washington), which extend inland and can have complex geometries. Not only is Kai working to incorporate those natural factors into his flood model, he has also worked with communities to incorporate their response to coastal hazards and the factors that are most important to them into his model.

Modeling climate change requires an immense amount of computing power. Kai uses super computers at the Texas Advanced Computing Center (TACC) to run a flood model and determine the fate of an estuary and its surroundings. But this is for one possible new climate, with one result (this is referred to as a deterministic model). Presenting these results can be misleading, especially if the uncertainty is not properly communicated.

Kai with his hydrodynamic model grid for Coos Bay, Oregon.

In an effort to model more responsibly, Kai has expanded into using what is called a probabilistic flood model, which results in a distribution of probabilities that an event of a certain severity will occur. Instead of just one new climate, Kai would model 10,000 climates and determine which event is most likely to occur. This technique is frequently used by earthquake engineers and often done using Monte Carlo simulations. Unfortunately, flooding models take time and it takes more than supercomputing to make probabilistic flooding a reality.

To increase efficiency, Kai has developed an “emulator”, which uses techniques similar to machine learning to “train” a faster flooding model that can make Monte Carlo simulation a possibility. Kai uses the emulator to solve flood models much like we use our brains to play catch: we are not using equations of physics, factoring in wind speed or the temperature of the air, to calculate where the ball will land. Instead we draw on a bank of experiences to predict where the ball will land, hopefully in our hands.

Kai doing field work at Bodega Bay in California.

Kai grew up in Gerlach, Nevada: Population 206. He moved to San Luis Obispo to study civil engineering at Cal Poly SLO and while studying, he worked as an intern at the Bodega Bay Marine Lab and has been working with the coast ever since. When Kai is not working on his research, he is brewing, climbing rocks, surfing waves, or cooking the meanest soup you’ve ever tasted. Next year, he will move to Chile with a Fulbright grant to apply his emulator techniques to a new hazard: tsunamis.

To hear more about Kai’s research, be sure to tune in to KBVR Corvallis 88.7 FM this Sunday May, 27 at 7 pm, stream the live interview at kbvr.com/listen, or find it in podcast form next week on Apple Podcasts.