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UC Davis Magazine

Volume 29 · Number 4 · Summer 2012

News & Notes

Waste to energy

In go 7.5 tons of food waste and a half-ton of unrecyclable cardboard each day. Out comes enough natural gas to meet more than one-third of a packaging company's energy needs.

The nation's first commercial high-solid organic waste-to-energy system, which debuted in Sacramento this spring, uses technology invented by a UC Davis researcher.

Ruihong Zhang, a professor of biological and agricultural engineering, has been working on her anaerobic digester technology for the past decade, bringing it from the laboratory to the pilot stage in 2006. When Clean World Partners, a Sacramento-based startup that licensed the technology from UC Davis, unveiled the biodigester in April at a Sacramento packaging company, it marked the first time her research has reached the market.

The anaerobic digestion system converts food waste from regional food producers, including Campbell's Soup Co., and unrecyclable corrugated material from American River Packaging into natural gas. The system will generate roughly 1,300 kWh of renewable energy per day, meeting about 37 percent of American River Packaging's electricity needs and preventing an estimated 2,900 tons of waste from entering landfills each year. The project has created about 22 jobs.

"This kind of project and technology is actually changing how societies treat and view waste as a resource, which, overall, leads to a better world, a cleaner environment and new jobs," said Zhang.

Anaerobic digestion relies on bacteria to break down biodegradable waste material in the absence of oxygen. Zhang's system turns that waste into such valuable byproducts as renewable energy, compost, water, and natural fertilizer. While anaerobic digestion is not a new technology in itself, operational and material-handling limitations had prevented its commercial adoption.

Unlike most other digesters that primarily treat liquid waste, such as manure from dairy farms and municipal wastewater, Zhang's high-rate digester technology can convert both liquid and solid waste, including food waste, yard waste, plant residues, paper and cardboard.

Zhang also sought to overcome two key barriers to the widespread use of anaerobic digesters: time and money. The new technology makes such waste conversion systems replicable, with many components prefabricated, reducing the time it takes to build them. The Clean World Partners system at ARP went from bare ground to energy production within 90 days and cost about $2 million to $3 million.

Zhang's system also turns waste into energy in half the time of other digesters and produces more gases that can be turned into clean energy. These efficiency improvements are expected to drive down cost and maximize the amount of energy produced and the volume of waste diverted from the landfill.


Moving swiftly on new police and protest policies

UC Davis is acting on the findings of an independent task force report that faulted the administration and the police department for the Nov. 18 pepper spray incident.

"We are moving swiftly to address these issues and any others that need attention," Chancellor Linda P.B. Katehi said in an April 22 message to the campus community.

This includes inviting an internationally recognized expert in police accountability to lead a campus forum and conducting an independent audit of police department policies and training records, and proposing needed changes.

Gathering feedback

Efforts to improve administrative coordination, collaboration and communication are underway — a new Campus Community Council will gather feedback on strategic campus issues, including those raised by the task force.

Retired state Supreme Court Associate Justice Cruz Reynoso chaired the task force, which presented its findings to more than 400 members of the campus community on April 11, the day of its release. Courtroom challenges had delayed the publication of the document, originally planned for March 6.

The report declared at the outset that the pepper spray event "should and could have been prevented."

A UC Davis law professor emeritus, Reynoso blamed state law — the police officers' "bill of rights" — for litigation regarding the report's release. He described that particular law as a "great disservice" to communities needing to learn the truth about police actions.

Reynoso said that while UC Davis officials had seemingly operated "in good faith," they made "many serious mistakes." From the administration's "informal" decision-making style to the Police Department's overall approach, the handling of the protesters was flawed on several levels. In the wake of the report, the Executive Council of the Davis Division of the Academic Senate formally censured the chancellor for the administration's handling of the incident.

As for the Reynoso task force, it suggested that UC Davis establish a clearly defined structure and set of operating rules for the crisis leadership team. Minutes of meetings should be recorded, and administrators should be trained in California Standardized Emergency Management procedures, especially in regard to public protest, the report advised.

Meanwhile, UC should provide policy guidance on what is acceptable protest behavior and what is not, according to the document.

Read about the campus's action plan and the full Reynoso report...

Launching Davis start-ups

Davis Roots, a recently formed nonprofit business accelerator bridging the city of Davis and UC Davis, is geared toward helping startup companies succeed and stay in the city, with two companies ready to move in.

Davis Roots was founded by Andrew Hargadon (far left), director of the UC Davis Child Family Institute for Innovation & Entrepreneurship and professor at the UC Davis Graduate School of Management, and Anthony Costello (far right), a founder of several successful startups and former chair of the city's Business and Economic Development Commission.

The first two companies are Barobo, a UC Davis spin-off that is building programmable robotics for the education and consumer markets, and Nuritas, launched by UC Davis postdoctoral student Nora Khaldi, who has developed a bioinformatics tool for discovering food components that affect health.


Concerns over nitrates in drinking water

One in 10 people living in California's most productive agricultural areas is at risk of exposure to harmful levels of nitrate contamination in their drinking water, according to UC Davis research.

The findings, reported in Addressing Nitrate in California's Drinking Water, come out of the first comprehensive scientific investigation of nitrate contamination in the Tulare Lake Basin, which includes Fresno and Bakersfield, and the Salinas Valley, which includes Salinas and areas near Monterey. It defines the extent of the problem, suggests solutions and outlines possible funding mechanisms.

"Cleaning up nitrate in groundwater is a complex problem with no single solution," said Jay Lund, director of the UC Davis Center for Watershed Sciences and a report co-author. "This report should help inform discussions among people involved with drinking water, waste discharge, and agricultural issues, including various local and state government agencies."

The report was commissioned by the California State Water Resources Control Board.


Puzzling behavior of dark matter

New results from NASA's Hubble Space Telescope confirm that, contrary to predictions, dark matter — the invisible substance that makes up much of our universe — and galaxies parted ways in the collision of two galaxy clusters 2.4 billion light-years away. Now, astronomers are left trying to explain dark matter's seemingly oddball behavior in the Abell 520 merging galaxy cluster.

"This result is a puzzle," said astronomer James Jee, project scientist in the Department of Physics, who led the Hubble study. "Dark matter is not behaving as predicted, and it's not obviously clear what is going on. Theories of galaxy formation and dark matter must explain what we are seeing."

During the collision of galaxy clusters that formed Abell 520, the dark matter collected into a "dark core" containing far fewer galaxies than would be expected if the dark matter and galaxies hung together. Most of the galaxies apparently have sailed far away from the collision.

Current theories of dark matter predict that galaxies should be anchored to the invisible substance, even during the shock of a collision.

Couples harmony

A key to long-lasting relationships

Despite life's ups and downs, couples whose feelings are in sync consistently over time are more likely to stay together, according to UC Davis research.

"We found that the longer periods of stability for the couple were great predictors of staying together," said Emilio Ferrer, a psychology professor and principal author of a research paper on the topic.

Researchers looked at surveys of 131 couples of various ages, married and unmarried, and analyzed their responses to daily questionnaires for at least 60 days and as long as 90 days. The subjects recorded their emotions for nine positive feelings such as "trusted," "physically intimate" and "free," and nine negative mood feelings, such as "discouraged," "lonely," "angry" and "deceived."

The researchers followed up after one to two years to inquire about each test pair's status as a couple. The researchers were able to get the information from 94 couples; 72 of them, or 76 percent, reported still being together.

The benefits of monogamy

Compared with monogamous societies, polygamous cultures see more rape, kidnapping, murder, assault, robbery, fraud, child neglect and child abuse, a UC Davis study suggests.

The reason: When men take multiple wives, the competition for fewer available women results in greater levels of strife, the researchers hypothesize.

The findings may explain the global rise of monogamy as the dominant marriage institution in recent centuries, replacing the polygamy once practiced by 85 percent of the world's societies, said Peter Richerson, an environmental science professor and co-author of the study.

"We wanted to understand both why monogamous societies have been economically more successful in the last few centuries and why monogamy has spread to many formerly polygamous societies in the course of modernization," he said.

Protecting global food supplies

A UC Davis agricultural economist will direct a $25 million federal program aimed at creating financial systems that can boost agricultural productivity and food security in developing countries.

The five-year project, funded by the U.S. Agency for International Development, will support research projects that design and test financial technologies, such as linked credit and insurance contracts, that can reduce the vulnerability of poor households to adverse events, making it easier for them to invest in new agricultural technologies and break the cycle of poverty.

"Many developing country farmers are mired in low levels of agricultural productivity, and new seeds and markets by themselves can go only so far in solving the problem," said Michael Carter, a professor of agricultural and resource economics and director of the newly funded project, known as the BASIS Assets and Market Access Collaborative Research Support Program.

When algebra comes too soon

Learning about algebra too early in life may do more harm than good for some students, according to UC Davis research.

In the study, UC Davis School of Education professors Michal Kurlaendar and Heather Rose, together with education programs consultant Don Taylor, found that the lowest-performing eighth-grade math students — who are least likely to be prepared for algebra — may be academically harmed by a policy that requires all eighth graders to take the course. Such a universal policy, first proposed by the California Board of Education, does not take into account the skills and needs of individual students, the researchers argue.


Mapping an earthquake zone in 3-D

Geologists have a new tool to study how earthquakes change the landscape down to a few inches, and it's giving them insight into how earthquake faults behave. A team of scientists from the U.S., Mexico and China reports the most comprehensive before-and-after picture yet of an earthquake zone, using data from the magnitude 7.2 event that struck near Mexicali, northern Mexico in April 2010.

"We can learn so much about how earthquakes work by studying fresh fault ruptures," said Michael Oskin, geology professor and lead author on the paper.

The team, working with the National Center for Airborne Laser Mapping (NCALM), flew over the area with LiDAR (light detection and ranging), which bounces a stream of laser pulses off the ground. New airborne LiDAR equipment can measure surface features to within a few inches. As a result, the researchers were able to make a detailed scan over about 140 square miles in less than three days, Oskin said.

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