e-Veritas Archive | December, 2016

Researchers Discover How Oxygen-Deprived Ducks Thrive

An international group of biologists discover how torrent ducks manage to thrive in low-oxygen environments.

By Jessica M. Castillo
UM News

A diving bird, the torrent duck is like a seal or penguin. Not in looks, of course, but in physiology. Like emperor penguins or Weddell seals, University of Miami researchers discovered, torrent ducks have among the highest concentrations of myoglobin, the protein that holds oxygen in muscle tissue.

That’s partly how this tiny waterbird species, averaging less than a pound, expertly dives in high-altitude rivers in the Peruvian Andes and has managed to survive for close to a million years in permanent states of hypoxia, or lack of oxygen. Travelers can see the ducks in the surging whitewater on the train ride to Machu Picchu.

“In most environments where you encounter hypoxia, it’s usually where animals will be able to escape it at some point,” said Neal Dawson, a postdoctoral biology researcher at the UM College of Arts and Sciences and McMaster University in Ontario, Canada, who with fellow UM biologists Kevin McCracken and Luis Alza discovered this adaptive trait on a July 2015 expedition. “In high altitudes, there’s no escaping it. These territorial ducks are stuck year-round with this hypoxia environment.”

The researchers’ expedition was part of a larger study, started in 2010, where scientists from UM, McMaster University, the University of British Columbia, the University of Alaska Fairbanks, and the CORBIDI institute in Peru set out to uncover what helps birds in the Andes thrive in such a high-altitude, low-oxygen environment.

For this latest study, the waterbird biologists focused on the torrent duck (Merganetta armata), a reluctant flier which, except when nesting, lives almost exclusively in the water. Working in remote villages north of Lima, the researchers learned how the ducks are able to hold their breath for a long time during repeated dives at high elevation by measuring their enzyme function across different metabolic pathways and the energy generation rates of their mitochondria, the cell’s powerhouse.

“As a diving species, the torrent duck will do everything it can to not fly,” noted Dawson, lead author of the study. “So, instead of looking at its ability to fly, we looked at its ability to dive. We looked at its leg muscles, enzymatic muscle activity, properties of the blood, and body measurements and noticed there are a whole host of changes that have really ameliorated its ability to dive at high altitudes.”

The bird has uniquely adapted to its resource-poor habitat. In addition to high levels of myoglobin, the researchers found that the torrent duck has high levels of hemoglobin, the oxygen-carrying protein in red blood cells. That enables it to “max out what their oxygen stores can be,” said McCracken, the James A. Kushlan Chair in Waterbird Biology and Conservation.

“If your hemoglobin levels were at 18 or 19 grams per deciliter, you’d be visiting your doctor to discuss it,” McCracken said. “The torrent ducks are going as high as 25. Double the concentration of yours. You would probably go into cardiac arrest if your hemoglobin was as high as a torrent duck’s.”

The scientists also discovered that the torrent duck’s hemoglobin has a high affinity for oxygen, which may affect its recovery time after a dive. The duck’s dive time is limited by the amount of oxygen it can hold in its lungs, air sacs, and intercellular oxygen stores.

“Once this oxygen runs out, the torrent duck has to resurface and recover quickly to be able to dive again,” said Dawson.

Recovery time is especially crucial for this species. “For the torrent duck, everything happens in the river,” said Alza, a doctoral student in the Department of Biology. Just as soon as they’re out of the water, the ducks are looking to dive back in for food or to escape external threats.

The oxygen-deprived torrent ducks also seem to be adapting to the high elevation by adjusting their energy consumption and fuel usage. Humans have access to energy from various fuel sources—including carbohydrates, fats and sugars. But most mammals in the wild are typically at the mercy of their environment and eat whatever energy sources are available; some even becoming specialists in digesting one source over another.

Digesting carbohydrates is more efficient per unit of oxygen, whereas digesting fats is more energy efficient per the actual amount of food that’s eaten.

The research team is currently analyzing the data but their preliminary results seem to contradict their initial hypothesis that this hypoxic species would tend to eat more carbs. The torrent ducks, it seems, tend to eat fats—mostly from aquatic insects—over carbs.

“Food might be more of a scarce resource than even oxygen at high altitudes,” said Dawson, who emphasized it’s still too early to say with certainty, but it looks like that’s what’s happening. “These ducks may be prioritizing getting their biggest bang for their buck every time they have a meal.”

The researchers also noted that, just over the last few years, they have seen a decline in the number of river ducks, which may be related to the impacts of the changing climate and increasing development near the duck’s habitat.

Poor development and infrastructure building pollutes the rivers with silt, choking aquatic insects and crashing the insect population. The ducks, with a staple diet of aquatic insects, must either move to another river or starve and die out.

Lima and other large cities along Peru’s Pacific coast depend on water from precipitation and glacial runoff. But the warming climate has melted many of the glaciers. In turn, rivers and artificial lagoons, built within the last 50 years for water retention, are drying up. Add in large and still growing urban populations and the pressures mount.

What does this mean for the ducks?

“No water, no ducks,” said Alza. “The duck is an easy way to monitor the river’s condition. If the ducks are still around, the river is quite healthy then.”

“The torrent ducks are a sentinel for conservation, particularly for protecting water resources used by local indigenous communities,” added McCracken, who also holds appointments as associate professor in the Department of Biology at the College of Arts and Sciences and in the Department of Marine Biology and Ecology at the Rosenstiel School for Marine and Atmospheric Science.

The researchers still have some more studies they’d like to conduct, such as on migration of juvenile ducks up and down the river, which would provide clues about the interplay between nature and nurture, or genetics and development in different environments. The scientists also would like to compare the torrent duck, a river duck with a vertical habitat, with the ruddy duck (Oxyura jamaicensis), another Andean diving bird species whose habitat is more isolated—in lakes and at either low or high altitude.

Their study “Mitochondrial physiology in the skeletal and cardiac muscles is altered in torrent ducks, Merganetta armata, from high altitudes in the Andes,” is published online in the Journal of Experimental Biology.

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Compliance and Ethics Week 2016 Draws Hundreds

Special to UM News

complianceThe University of Miami’s inaugural Compliance and Ethics Week  was a big success, drawing  more than 900 attendees and more than 30 compliance, ethics, and risk areas to the carnival-themed information fairs held at each campus and various seminars last month.

Representatives from such departments as Athletics Compliance, the Faculty and Staff Assistance Program, Billing Compliance, Environmental Health and Safety, the Office of Research Administration, and Human Resources distributed information and answered questions about their programs and responsibilities as they relate to compliance and ethics. The fairs, which  took place November 7-11, provided a great opportunity for students, faculty, and staff to engage and learn about the University’s various compliance, ethics, and risk management initiatives and meet various individuals that could serve as a resource for them.

During the seminars, many employees enjoyed the opportunity to learn about the Fair Labor Standards Act, the Family and Medical Leave Act, Workers’ Compensation, and more.

“The Compliance and Ethics Week celebration was a great opportunity for many offices to collaborate and show how compliance and ethics responsibility is really about learning how to do your job better,” said Rudolph Green, vice president and chief compliance officer.

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School of Law Offers Legal Consultations for Undocumented/DACA Students at UM

The School of Law’s Immigration Clinic is offering confidential and free
consultations to UM students who are undocumented or in DACA (Deferred
Action for Childhood Arrivals) status. Interested students should email
immigrationclinic@law.miami.edu and ask for an appointment. Professors
Romy Lerner and Rebecca Sharpless, practicing immigration lawyers, will be
providing the consultations. Please note that these consultations are only for students who are undocumented or in DACA status.

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Center for Green Aviation to Focus on Electric Planes

Special to UM News

electric-aircraftCORAL GABLES, Fla. (December 13, 2016)—Funded in part with a grant from the Emil Buehler Perpetual Trust, the College of Engineering  has established a Center for Green Aviation to further develop green, zero-direct-emission electric aircraft, with a particular focus on increasing their range and payload capacity. The first such research facility in the United States, the facility will provide the next generation of electric aircraft engineers hands-on experience in cutting-edge technologies.

The center will capitalize on the expertise and unique technology of the college’s Mechanical and Aerospace Engineering Department,  which the National Aeronautics and Space Administration (NASA),  the Defense Advanced Research Projects Administration, (DARPA) and Boeing have recognized with grants and contracts.

“The Center for Green Aviation will develop technologies that make this green transportation option practical for future aviation,” says Ge-Cheng Zha,  co-director of the center and a professor in the Mechanical and Aerospace Engineering Department. “We will begin with small General Aviation aircraft and thin-haul aircraft. Today’s electric aircraft can only go short distances of 100 miles or so. Our research will change the face of consumer aircraft, as well as unmanned aerial drone systems.”

Researchers at the college have already demonstrated a novel design, which was able to fly more than twice the distance of a similarly sized electric aircraft that used conventional design. Their new design allowed for a 510-mile range with four passengers. This design is based on a flow control technology, called Co-Flow jet airfoil, which was developed at the University of Miami. The technology offers radically increased aerodynamic efficiency and lift coefficient.

Integrating that design with the college’s discoveries and expertise in aerodynamics science, electric power sources using structure batteries, and multi-functional composite materials, the Center for Green Aviation will develop technologies including the ultra-high-lift, high-efficiency co-flow jet (CFJ) wing; ultra-high-capacity electric energy storage devices (UHEES); integrated multifunctional structural batteries; and high-efficiency, low-noise swept propellers. The center will be integrated with the college’s educational programs for graduate and undergraduate students.

“A few years ago, everyone thought electric cars were just a dream. Now, you see Tesla and many other manufacturers that have turned that dream into a reality. The same is going to happen with green aviation,” says Jean-Pierre Bardet, dean of the College of Engineering and director of the center. “Now, we need partnerships between academic researchers and industry in order to update and fine-tune the technology and bring electric aircraft to market. By bringing together science, technology, engineering, and practice, we will be able to develop products with tangible benefits for society. Having the University of Miami at the forefront of such a development is important, not only for the University, but for the world of aviation.”

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Experience I Am the U, UM’s New Employee Orientation Program, at a Pilot Session This Week

i-am-the-u-name-tags2Current faculty and staff are invited to experience I Am the U, a redesigned global orientation program, at a pilot session this week. Debuting later this month, I am the U will give newly hired faculty and staff an interactive and exciting introduction to the University of Miami’s purpose, history, values, and culture on their first day of work. Hosted by Talent and Organizational Development, the pilot sessions are from 8:30 a.m. to 4:30 p.m, but attendees need not stay the whole day. Breakfast and lunch will be provided and space is available on a first-come, first-served basis. Register for the session of your preference by clicking on the dates below.

January 9, 2017
8:30 a.m. to 4:30 p.m.
Watsco Fieldhouse

January 11, 2017
8:30 a.m. to 4:30 p.m.
Watsco Fieldhouse

January 12, 2017
8:30 a.m. to 4:30 p.m.
Watsco Fieldhouse

For any questions or concerns regarding this program please contact iamtheu@miami.edu.

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