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Egghead is a blog about research by, with or related to UC Davis. Comments on posts are welcome, as are tips and suggestions for posts. General feedback may be sent to Andy Fell. This blog is created and maintained by UC Davis University Communications, and mostly edited by Andy Fell.

UC Davis scientists demonstrate DNA-based electromechanical switch

By AJ Cheline

A team of researchers from the University of California, Davis and the University of Washington have demonstrated that the conductance of DNA can be modulated by controlling its structure, thus opening up the possibility of DNA’s future use as an electromechanical switch for nanoscale computing. Although DNA is commonly known for its biological role as the molecule of life, it has recently garnered significant interest for use as a nanoscale material for a wide-variety of applications.

In their paper published in Nature Communications, the team demonstrated that changing the structure of the DNA double helix by modifying its environment allows the conductance (the ease with which an electric current passes) to be reversibly controlled. This ability to structurally modulate the charge transport properties may enable the design of unique nanodevices based on DNA. These devices would operate using a completely different paradigm than today’s conventional electronics.

The A-form of DNA between two electrodes.

The A-form of DNA between two electrodes.

“As electronics get smaller they are becoming more difficult and expensive to manufacture, but DNA-based devices could be designed from the bottom-up using directed self-assembly techniques such as ‘DNA origami’,” said Josh Hihath, assistant professor of electrical and computer engineering at UC Davis and senior author on the paper. DNA origami is the folding of DNA to create two- and three-dimensional shapes at the nanoscale level.

“Considerable progress has been made in understanding DNA’s mechanical, structural, and self-assembly properties and the use of these properties to design structures at the nanoscale. The electrical properties, however, have generally been difficult to control,” said Hihath.

New Twist on DNA? Possible Paradigms for Computing

In addition to potential advantages in fabrication at the nanoscale level, such DNA-based devices may also improve the energy efficiency of electronic circuits.  The size of devices has been significantly reduced over the last 40 years, but as the size has decreased, the power density on-chip has increased. Scientists and engineers have been exploring novel solutions to improve the efficiency.

“There’s no reason that computation must be done with traditional transistors. Early computers were fully mechanical and later worked on relays and vacuum tubes,” said Hihath.  “Moving to an electromechanical platform may eventually allow us to improve the energy efficiency of electronic devices at the nanoscale.”

This work demonstrates that DNA is capable of operating as an electromechanical switch and could lead to new paradigms for computing.

To develop DNA into a reversible switch, the scientists focused on switching between two stable conformations of DNA, known as the A-form and the B-form. In DNA, the B-form is the conventional DNA duplex that is commonly associated with these molecules. The A-form is a more compact version with different spacing and tilting between the base pairs. Exposure to ethanol forces the DNA into the A-form conformation resulting in an increased conductance. Similarly, by removing the ethanol, the DNA can switch back to the B-form and return to its original reduced conductance value.

One Step Toward Molecular Computing

In order to develop this finding into a technologically viable platform for electronics, the authors also noted that there is still a great deal of work to be done. Although this discovery provides a proof-of-principle demonstration of electromechanical switching in DNA, there are generally two major hurdles yet to be overcome in the field of molecular electronics.  First, billions of active molecular devices must be integrated into the same circuit as is done currently in conventional electronics. Next, scientists must be able to gate specific devices individually in such a large system.

“Eventually, the environmental gating aspect of this work will have to be replaced with a mechanical or electrical signal in order to locally address a single device,” noted Hihath.

The UC Davis members of the team included Juan Manuel Artés and Yuanhui Li of the Department of Electrical and Computer Engineering, and the University of Washington members included M.P. Anantram and Jianqing Qi from the Electrical Engineering Department.

This work is funded by the UC Davis Grant Research Investments in the Sciences and Engineering (RISE), which encourages interdisciplinary work to solve problems facing the world today, as well as the National Science Foundation (Grants 1231915 and 102781).

More information:

J. M. Artés et al. “Conformational Gating of DNA Conductance,” Nature Communications, vol. 6, pp. 8870, 2015. DOI: 10.1038/ncomms9870

Other RISE success stories

UC Davis RISE Team Granted $15.5 Million to Build World’s First Total-Body PET Scanner

UC Davis Scientists Develop Rapid, Low-Cost Method to Detect Pathogens

AJ Cheline is communications director for the UC Davis Office of Research

 

 

 

 

 

Chemwiki free textbook effort expands with $600,000 grant

By Becky Oskin

College students in the STEM fields could see sizable savings thanks to a $600,000 grant awarded to an open source textbook project developed at the University of California, Davis.

The ChemWiki project recently received $600,000 from the National Science Foundation to support further expansion of its open source textbooks into fields including statistics, math, geology, physics, biology and solar energy.

Digital course materials are steadily climbing in use in response to textbook cost concerns, according to an annual survey released in July by the National Association of College Stores. In August, the University of Maryland announced plans to completely eliminate print textbooks this academic year.

The ChemWiki is one of seven wikis that provide free, peer-reviewed textbooks and course materials, such as homework sets, online under an open license. Students can download the texts for free and professors can customize the materials for their courses, such as by rearranging the sequence of information. The seven wikis focus on STEM (science, technology, engineering and mathematics) topics such as biology, math, geology and physics.

“We’re trying to make a central database to completely supplant STEM textbooks,” said ChemWiki founder Delmar Larsen, a UC Davis chemistry professor. “This grant will give us three times the resources than we have had before. Our goal is to expand our reach to 300 million students annually, and a half-billion page views,” Larsen said.

Half of the grant will fund the ChemWiki and half will fund expanding the textbook network, Larsen said. The ChemWiki grant also supports faculty at Sonoma State University, Diablo Valley College, Contra Costa Community College, Hope College in Holland, Michigan, University of Arkansas at Little Rock, Howard University and College of Saint Benedict & Saint John’s University.

Battle of the books

Since March 2014, ChemWiki textbooks have been used in more than 30 different classes at campuses in the United States, Canada and the United Arab Emirates. These courses have saved students more than $1 million, Larsen said.

Some critics of open source textbooks complain that the texts can be rife with errors and therefore lower educational quality for students. However, Larsen said, ChemWiki course materials are peer-reviewed, like traditional print textbooks. “I get about four to five correction requests a week and once fixed they are never a problem, in contrast to traditional textbooks,” Larsen said.

Larsen and his colleagues also pitted the ChemWiki against traditional print textbooks in a recent study funded by a 2013 NSF grant. The study results were published Sep. 17, 2015, in the journal Chemistry Education and Research Practice.

In spring quarter 2014, Larsen taught half of a UC Davis general chemistry class, more than 475 students, using a standard print textbook. A similar number of students heard the same lectures from Larsen and his teaching assistants and studied the same material using the ChemWiki.

The results showed the learning gains for both classes were not statistically different when accounting for student demographics. There was no statistical difference in either class’s performance, Larsen said. Furthermore, high ChemWiki-using students (more than 400 total page views) showed about an eight percent increase in course performance. The results were evaluated by researchers from the Center for Education and Evaluation Services at the UC Davis School of Education.

Millions of visitors

The online textbooks are called wikis because faculty and student volunteers write them. About 5,000 students and 100 faculty have edited the ChemWiki or donated content since 2008. A small group of volunteers is currently translating the organic chemistry textbooks into Spanish and French.

“We need a lot of help to move the project forward,” Larsen said.

The ChemWiki website now has 8 million page views monthly, primarily from students. ChemWiki is the most visited chemistry website in the world and most visited UC Davis website, Larsen said. Currently, about 30 percent of Internet visitors to “ucdavis.edu” head to the ChemWiki.

Larsen said he launched the ChemWiki in 2008 because he was concerned about the high cost of textbooks. “I thought $200 was atrocious for a physical chemistry textbook,” Larsen said. “My response was, ‘I can do better, I should do better.’” Today, a single textbook for health or science majors can cost more than $350, Larsen said.

Saving money

Open source textbooks are one of several digital options available to college instructors who are concerned about student costs.

UC Davis is also a leader in providing low-cost digital textbooks to students. Through its content licensing program, students (and faculty, who ultimately choose the textbooks) can use digital textbooks provided through UC Davis Stores. The lower digital prices saved students more than $1 million in the program’s first year.

UC Davis was also the first university to offer textbook price comparisons online and the first university to partner with Amazon. UC Davis provides the largest textbook rental program per capita in the United States.

UC Davis will host the National Association of College Stores’ 2016 Textbook Affordability Conference in April 2016.

Becky Oskin writes about mathematical and physical sciences for the UC Davis College of Letters and Science. Follow her on Twitter at @beckyoskin.

Guided ultrasound plus nanoparticle chemotherapy cures tumors in mice

By Holly Ober

Thermal ablation with magnetic resonance–guided focused ultrasound surgery (MRgFUS)  is a noninvasive technique for treating fibroids and cancer. New research from UC Davis shows that combining the technique with chemotherapy can allow complete destruction of tumors in mice.

MRgFUS combines an ultrasound beam that heats and destroys tissue with a magnetic resonance imaging to guide the beam and monitor the effects of treatment. The effectiveness of the treatment can be limited by the need to spare normal tissue or critical structures on the tumor margins, as well as the need to eliminate micrometastases.

In a new paper in The Journal of Clinical Investigation, Katherine W. Ferrara, distinguished professor of biomedical engineering at UC Davis, and colleagues report on a strategy that can destroy an entire tumor without thermal destruction of the tumor margin. Her group demonstrated a dramatic increase in the concentration of anti-cancer chemotherapy within several types of MRgFUS thermal ablation-treated tumors.

The tumor shown at top left is heated with ultrasound (top right) resulting in accumulation of drug (bottom images). UC Davis image.

Clockwise from top left: Tumor (blue arrows) heated with ultrasound (red dashed line); heat map of tumor during treatment; PET scan shows nanoparticles in surviving tumor margin; bright contrast agent shows area damaged by heat. UC Davis image.

“MRgFUS is already FDA approved for the treatment of uterine fibroids and palliation of bone metastases. We hope to expand the indication for MRgFUS by supplementing it with chemotherapy,” said first author Andrew Wong, a graduate student with the UC Davis Physician Scientist Training Program.

Ferrara’s previous research has shown that ultrasound-induced mild hyperthermia can enhance the accumulation of tiny nanoparticles carrying anti-cancer drugs, but the accumulation is dependent on the type of tumor. Her group hypothesized that combining thermal ablation and chemotherapy could improve efficacy across multiple types of tumors.

The team used a variety of techniques including combined positron emission tomography/computed tomography (PET-CT), magnetic resonance imaging, autoradiography, and fluorescence imaging to track nanoparticles loaded with the chemotherapy drug doxorubicin in a mouse model of breast cancer.

They found that as the ultrasound damaged the tumor and induced a local immune response, nanoparticles accumulated in the tumor and the local drug concentration increased 50-fold. The high drug concentrations continued over several weeks, increasing total exposure of the tumor to the drug.

Ferrara’s research team found that the enhanced drug accumulation induced by MRgFUS resulted in improved survival and a consistent cure in their preclinical model of breast cancer, even when part of the tumor was left intact.

They also demonstrated that an effective cure could be achieved with a carefully designed protocol involving heat-activated nanoparticles, which, when gently heated by ultrasound, release their chemotherapeutic payload in the vasculature surrounding the tumor.

Additional members of the team included Brett Z. Fite, Yu Liu, Josquin Foiret, Azadeh Kheirolomoom, Jai W. Seo, Katherine D. Watson, Lisa M. Mahakian, Sarah Tam and Alexander D. Borowsky. The work was supported by grants from the National Institutes of Health.

More information

Link to the paper (subscription may be required)

More about MRgFUS from UCLA Radiology

Holly Ober writes for the UC Davis Department of Biomedical Engineering. 

“Love hormone” oxytocin, possible anxiety drug, shows different effects in male and female mice

By Kathleen Holder

Clinical trials are testing whether oxytocin, sometimes called the “love hormone” for its role in intimacy and social bonding, has potential as a treatment for anxiety, depression and post-traumatic stress disorder. New research by behavioral neuroscientists Michael Steinman, Brian Trainor and colleagues at UC Davis suggests oxytocin may have different effects in men and women—and in certain circumstances the hormone may actually trigger anxiety.

In a series of experiments at the UC Davis Department of Psychology, the team administered doses of oxytocin with a nasal spray to male and female mice. Some of the mice were bullied by an aggressive mouse, an experience that reduces motivation to associate with unfamiliar mice. Consistent with previous studies, oxytocin increased the motivation for social interaction in stressed males.

Mouse

Male and female California mice show different responses to oxytocin, a possible treatment for anxiety and stress. (Mark Chappell/UC Riverside)

However, in stressed females, oxytocin had no effect. When non-stressed females received oxytocin, social motivation was reduced. This effect of oxytocin is similar to the effect of social stress.

“Reduced social motivation can be part of a depression-like syndrome,” said Trainor, an associate professor of psychology.

Trainor and colleagues found important differences in how stress affected the production of oxytocin. After stress, nerve cells in the brain produced more oxytocin in females but not in males. Steinman used a molecular marker to show that these oxytocin-producing cells were also more active in females that experienced stress. Steinman suggests, “This may help explain why oxytocin nasal spray makes females avoid social contact even though they did not experience social stress.”

Clinical studies have found that women with depression or PTSD have elevated oxytocin levels. Usually this result has been thought to reflect an increased drive for social support. The results of Trainor and colleagues suggest an alternate possibility.

“Our results show that stressed females have both reduced social motivation and increased oxytocin. It’s possible that oxytocin might contribute to a depression-like syndrome in females,” Trainor said. “If correct, inhibiting oxytocin action might have unanticipated benefits.”

The surrounding environment also influenced the effects of oxytocin. If mice were tested in a familiar home cage instead of a new environment, oxytocin reduced stress-related behaviors in males and females. This finding shows that the effects of oxytocin depend whether the environment is familiar or unfamiliar.

Trainor said his lab’s findings have implications for studies investigating the utility of oxytocin as a therapeutic.

“Most clinical studies investigating oxytocin as a treatment for depression or anxiety include only males,” he said. “It’s important to include both men and women in these studies. The effect of oxytocin may be different if administered by an unfamiliar person or by a person with whom the patient has a personal relationship.”

The UC Davis research project was supported by the National Institutes of Mental Health.

The results are to be published in Biological Psychiatry. An advance copy is available online.

In addition to Trainor and Steinman, a UC Davis Ph.D. alumnus who is now a post-doctoral researcher at New York University, co-authors were graduate student Natalia Duque-Wilckens; Gian Greenberg, a Ph.D. alum and a post-doctoral researcher at the Oregon Health and Sciences University; staff researcher Rebecca Hao; Katherine Campi, a Ph.D. alum who is now an assistant professor at Sierra College; Sarah Laredo, a Ph.D. alum who is now a post-doctoral researcher at Scripps Research Institute; graduate student Abigail Laman-Maharg; former undergraduates Claire Manning, Ian Doig, Kennan Walch and Eduardo Lopez, who all graduated in 2013; and psychology professor Karen Bales.

Additional information about this research is available at trainorlab.ucdavis.edu.

Kathleen Holder writes about Social Sciences for the College of Letters and Science at UC Davis. Follow her on Twitter: @kmholder.

 

Refael Klein flies the Aggie flag at the South Pole

If you think it’s been a bit chilly in the Sacramento region this week, spare a thought for UC Davis alumnus Refael Klein, lieutenant junior grade in the Commissioned Officer Corps of the National Oceanic and Atmospheric Administration. On a recent day temperatures climbed to 35 degrees below zero Fahrenheit at the South Pole, Klein’s home for the next year.

Aggie flag at South Pole

UC Davis alumn Refael Klein at the geographic South Pole, Nov. 2015. Klein will spend a year at the pole studying climate change.

“It’s been a big dream of mine to visit Antarctica,” said Klein in an interview before he left the U.S. “I feel very fortunate to have the opportunity.”

Klein graduated from UC Davis in 2010 with a degree in biological systems engineering and joined the NOAA Corps the following year. The Corps is the seventh uniformed service of the United States, tracing its history back to 1807 and the “Survey of the Coast” ordered by Thomas Jefferson. It operates research ships and aircraft and manages research projects around the world.

After Officer Candidate School, Klein served on research vessels in Hawaii and on the U.S. West Coast. He is currently assigned to NOAA’s global monitoring division, collecting information on the Earth’s atmosphere and changing climate from research stations around the world. In this capacity, he worked for a year in American Samoa and now a 13-month posting to the South Pole.

Klein will run the climatological laboratory at the South Pole base, running experiments and collecting data on behalf of other scientists. He will also act as lead scientist for the National Science Foundation, which operates the base, and liaison between all the various researchers there.

“I’m looking forward to getting involved in a science program that’s been running since the 1960s,” he said.

While the coastal regions of Antarctica are rugged with mountains and glaciers, the Pole itself is a high, icy desert, 10,000 feet up and flat in all directions. Over winter, the population of the base shrinks as complete darkness sets in.  Klein had to complete extensive physical and mental health exams and intensive training on leadership in confined environments before being cleared to go.

“It’s very akin to working on a ship,” Klein said. “You form a miniature society.”

The polar base does have internet access year round though, and Klein is blogging about his experiences for Voice of America’s Science World web site.

 

 

 

 

 

Innovation event jumpstarts dialogue on food, agriculture and health

By Kyeema Zerbe and Jennifer Hebets

The first ever event by the Innovation Institute for Food and Health (IIFH) struck surprising consensus in the food, agriculture and health agenda. The Challenge Definition Workshop held Oct. 29 set the stage for dialogue around such issues as crop selection, soil health, nutrition education, consumer decision-making, and technology feasibility – all under the overarching themes of health, sustainability, knowledge and governance. Next week, focus groups will deliberate the research questions behind such challenges, in preparation for the tour, hackathon and conference scheduled at the Solution Summit on December 2 and 3 in the UC Davis Conference Center.

Participants at the Oct. 29 IIFH Challenge Definition Workshop discussed food, hunger and innovation. Image ©Fred Greaves 2015

Participants at the Oct. 29 IIFH Challenge Definition Workshop discussed food, hunger and innovation. Image ©Fred Greaves 2015

The workshop saw the inaugural convening of many perspectives that will make up the innovation agenda. The charge for the Oct. 29 event was ambitious: define the most pressing issues facing food, agriculture and health. More than 100 participants from a unique cross-section of investors, entrepreneurs, students, researchers, and corporations represented the entire food system, from production to processing, and distribution to sale and education.

With an invigorating kick-off by  acting director Justin Siegel, and Mixing Bowl Hub cofounder Rob Trice, the event was powered by a shared vision for building uncommon collaborations and game-changing solutions to the challenges at hand. Through several rounds of active deliberation, more than 30 issues facing food, agriculture and health were narrowed down to a half dozen grand challenges. From there, a lively conversation resulted in consensus on four collective themes: health, sustainability, knowledge and governance.

The exercise proved that issues facing food, ag and health can each be defined from the perspective of those joining the conversation. The diverse participant mix revealed that such topics as undernutrition, GMOs, or technology, can be tackled from multiple angles. Therefore, it becomes necessary to establish common terms as a critical first step toward creative collaboration and consensus building.

In November, the next round of events will include Focus Group Retreats in which smaller groups of multifunctional teams will dive deeper into issues identified at the workshop. On December 2 and 3 the IIFH will host its first public Solution Summit in which hack teams, keynotes and panelists will explore innovative solutions with a broader audience.

The IIFH’s first event served as clear evidence of the much needed movement for promoting cross-sectoral collaboration to solve complex issues. The process of bringing together diverse perspectives, expertise and priorities is inevitably “messy”. However, as history has proven time and again, the greatest innovations often come from the least expected solutions.

Join the conversation by attending the next public event, the Solution Summit on December 2 and 3 – register here: http://foodaghealth.solutions/summit/

Kyeema Zerbe is Program Director for the Innovation Institute for Food and Health.

Often decried, polygyny may have some advantages

Is being a “sister wife” always a bad thing?

By Kathleen Holder

Much of the world frowns on the practice of polygamy. Most countries around the globe ban or restrict marriages to more than one spouse at a time. And polygyny—where one husband has more than one wife—is decried by the United Nations Human Rights Committee and women’s rights organizations as discriminatory to women.

But a new study of polygyny in Tanzania finds that the practice of sharing a husband may, in some circumstances, lead to greater health and wealth for women and their children.

UC Davis anthropologist Monique Borgerhoff Mulder and colleagues compared polygynous and monogamous households in 56 villages in northern Tanzania, where polygyny is widespread among certain ethnic groups, including the Maasai.

When comparing households within individual villages, polygynous households often had better access to food and healthier children. Polygynous households also owned more cattle and farmed more land than monogamous households. These findings support evolutionary anthropological accounts of marriage indicating that polygyny can be in a woman’s strategic interest when women depend on men for resources.

“If you have a choice of a guy who has 180 cows, lots of land and other wives, it might be better for you to marry him rather than a guy who has no wives, three cows and one acre,” Borgerhoff Mulder said.

Consistent with prior research, the study found that polygyny was associated with low food security and poor child health when looking at data across all villages. However, this pattern was accounted for by the tendency of polygyny to be most common in ecologically vulnerable and marginalized ethnic groups. This error of interpretation is known as the “ecological fallacy”, and flaws all previous analyses of large data sets like the Demographic and Health Surveys.

“Our study suggests that highly polygynous, predominantly Maasai, villages do poorly not because of polygyny, but because of vulnerability to drought, low service provision and broader socio-political disadvantages,” said David Lawson, a population health lecturer at the London School of Hygiene & Tropical Medicine and lead author of the study published in the Proceedings of the National Academy of Sciences.

Tanzania faces a high burden of food insecurity and malnutrition: 45 percent of children are of low height for their age, indicating chronic malnutrition with long term impacts on physical and cognitive development. Previous research by Lawson, Borgerhoff Mulder and colleagues showed that nearly 60 percent of Tanzanian Maasai children experience stunting.

The United Nations states that polygyny contravenes a woman’s right to equality with men and can have such serious emotional and financial consequences for her and her dependents that such marriages ought to be discouraged and prohibited.

However, the researchers highlight the importance of local context in studying the health implications of cultural practices, and suggest that in some settings, prohibiting polygyny could be disadvantageous to women by restricting their marriage options.

“The issue is not the number of partners,” Borgerhoff Mulder said. “Women should be assured the autonomy to make the decisions they want.”

The study is limited to food security and health, and cannot tell us about the wider potential for polygyny to cause harm, the researchers said. They also note that polygyny was only associated with superior outcomes when fathers and children were co-resident: outcomes for other polygynously-married women were indistinguishable from those of monogamous women. This suggests that any potential benefits of sharing a husband may be limited to the primary wife within a polygynous marriage.

The research was conducted in partnership with Savannas Forever Tanzania, which was co-founded by Borgerhoff Mulder, as well as the National Institute for Medical Research in Tanzania.

More information: Read the paper here

Kathleen Holder writes about social sciences for the UC Davis College of Letters & Science. Follow her on Twitter @kmholder.

UC Davis physicist praises 2015 Nobel prize for neutrinos

The sun, as seen in neutrinos captured by the Super-K experiment in Japan (R. Svoboda and K. Gordan).

The sun, as seen in neutrinos captured by the Super-K experiment in Japan (R. Svoboda and K. Gordan).

Robert Svoboda contributed to Nobel-winning neutrino experiments

By Becky Oskin

Billions of mysterious particles called neutrinos bombard your body every day. But catching even one neutrino is a huge effort. Nearly all neutrinos pass through people — and even our planet Earth — without a trace.

“There are 65 million neutrinos going through your thumbnail every second,” said Robert Svoboda, a UC Davis physics professor who has studied neutrinos for more than 25 years. “Only one will stop in your body during your lifetime.”

Svoboda collaborated on one of the two neutrino experiments honored this year by the 2015 Nobel Prize in Physics. The Nobel prizes went to Takaaki Kajita, leader of the Super-Kamiokande Collaboration in Japan, and Arthur McDonald, who leads the Sudbury Neutrino Observatory Collaboration in Canada.

Researchers want to understand neutrinos because the particles carry information about the inner workings of stars. The intense nuclear reactions inside stars, supernovas and nuclear reactors all produce neutrinos. Svoboda also thinks neutrinos may have played a role in creating more matter than antimatter just after the big bang. The big bang should have produced equal parts matter and antimatter, but our universe has mostly matter and seemingly very little antimatter, he said.

A weighty discovery

Svoboda joined the Super-Kamiokande experiment, or Super-K, in the early 1990s. Built in an old mine in Japan, the Super-K experiment centers on a 50,000-ton tank of purified water (about 13 million gallons). The tank’s sheer size means researchers can catch a few neutrinos randomly colliding with molecules in the water. Sensors monitor the faint light flashes created by these neutrino collisions. Super-K snags about 20 to 30 neutrinos on a typical day, Svoboda said.

Physicists at Super-K already knew neutrinos come in three types, also called flavors: electron, muon and tau. The names refer to the particles produced when a neutrino collides with matter. (UC Davis physicist Phil Yager, professor emeritus, helped capture the first direct evidence of the tau neutrino in the late 1990s.)

“Flavor is a name given to something we don’t quite understand,” Svoboda said. “We don’t know why there are three flavors. We’re probably missing something very important, and don’t know it yet.”

The Super-K group discovered that neutrinos oscillated, switching between different types. The Sudbury Neutrino Observatory confirmed that neutrinos switch flavors on their journey from the Sun. The oscillation observations confirmed that neutrinos have a very tiny mass. Before the experiment, most physicists thought neutrinos were massless particles. These results meant the Standard Model of the universe and its particles was wrong.

Next steps

New neutrino experiments may help solve some of these riddles. Svoboda is a leading scientist on the Deep Underground Neutrino Experiment (DUNE), a mega-neutrino detector at Fermilab in Batavia, Illinois. The DUNE experiment could lead to a better estimate of the mass of the Universe, and an improved measure of neutrino mass.

Whatever the results from DUNE, Svoboda expects more surprises from scientists studying neutrinos.

“This is the fourth Nobel prize for neutrino research, and it won’t be the last one,” Svoboda said.

Becky Oskin writes about science for the UC Davis College of Letters & Science. Follow her on Twitter @BeckyOskin.

Innovation Institute kicks-off “uncommon collaboration” for food and health with workshop

By Kyeema Zerbe

The Innovation Institute for Food and Health (IIFH) at UC Davis is kicking off a uniquely open collaboration on solving critical challenges in food, agriculture and health with an open workshop Oct. 29 inviting participants from all disciplines to provide input on the institute’s strategic focus.

Food and nutrition insecurity remain serious issues for more than 50 developing countries, according to the 2015 Global Hunger Index. And even as many as 10 percent of populations in developed countries go hungry, including in the fertile lands of California’s Central Valley. The UN Food and Agriculture Organization reports that almost 800 million people worldwide are chronically undernourished. With the global population expected to reach nearly 10 billion by 2050, society faces an uncertain future that demands a coordinated response from all sectors to improve access to adequate nutrition.

The IIFH was launched in January 2015 as a ground-breaking academic-corporate partnership between UC Davis and founding partner Mars, Incorporated, and seeks to establish a framework for accelerating innovative solutions to implementation.

As part of an inclusive strategy designed for maximum impact, the IIFH is gearing up to welcome stakeholders from across all sectors to help set the innovation agenda. A central tenet of the proposed approach involves partnering with researchers on a series of critical questions that, if addressed, would significantly improve human welfare locally or globally. Scale-up to application can involve any number of unique collaborations and additional corporate entities.

“Nutrition insecurity is widely prevalent in both developing and developed countries. We must look at where new systems need to be built and how current systems can be improved to provide safe, sustainable and secure nutrition for all,” said Justin Siegel, IIFH acting director and assistant professor of chemistry at UC Davis. “By enabling multi-sector partnerships and uncommon collaborations, the IIIFH can accelerate research discovery from inception to wide-scale delivery and community impact.”

At the first workshop on October 29, the IIFH invites questions from academic, industry, government, and community participants on the most important challenges for the entire food, agriculture and health ecosystem. This might include: what and how crops should be grown, how should they be processed, what products should they be transformed into, how to deliver those products equitably, how to educate consumers about nutritious products, or how to evaluate product impact on human health and welfare.

These questions will be refined in targeted consultations through November, when the IIFH will transition to eliciting potential solutions. Joining with the World Food Center, Apps for Ag and The Mixing Bowl Hub on December 2 and 3, the first open Solution Summit will engage participants in developing the best collaborative answers to pressing questions.

In the New Year, IIFH will launch an open call for proposals, with the goal of initiating projects on the three broad challenges of sustainable agriculture, food safety, and nutrition for all in spring 2016. To express interest in attending a future event, visit https://www.surveymonkey.com/r/SJXS7D9.

The “sixth sense:” How do we sense electric fields?

A variety of animals are able to sense and react to electric fields, and living human cells will move along an electric field, for example in wound healing. Now a team lead by Min Zhao at the UC Davis Institute for Regenerative Cures has found the first actual “sensor mechanism” that allows a living cell to detect an electric field. The work is published Oct. 9 in the journal Nature Communications.

“We believe there are several types of sensing mechanisms, and none of them are known. We now provide experimental evidence to suggest one which has not been even hypothesized before, a two-molecule sensing mechanism,” Zhao said.

Zhao and colleagues have been studying these “electric senses” in cells from both larger animals (fish skin cells, human cell lines) and in the soil-dwelling amoeba Dictyostelium. By knocking out some genes in Dictyostelium, they previously identified some of the genes and proteins that allow the amoeba to move in a certain direction when exposed to an electric field.

In the new work, carried out in a human cell line, they found that two elements, a protein called Kir4.2 (made by gene KCNJ15) and molecules within the cell called polyamines, were needed for signaling to occur. Kir4.2 is a potassium channel – it forms a pore through the cell membrane that allows potassium ions to enter the cell. Such ion channels are often involved in transmitting signals into cells. Polyamines are molecules within the cell that carry a positive charge.

Zhao and colleagues found that when the cells were in an electric field, the positively-charged polyamines tend to accumulate at the side of the cell near the negative electrode. The polyamines bind to the Kir4.2 potassium channel, and regulate its activity.

He cautioned that they do not yet have definitive evidence of how “switching” of the potassium channel by polyamines translates into directional movement by the cell.

Contributors to the paper are: Ken-ichi Nakajima, Kan Zhu, Yao-Hui Sun, Yoshihiro Izumiya, Bence Hegyi, Qunli Zeng, Christopher Murphy, J. Victor Small, Ye Chen-Izu, and Josef Penninger, with affiliations at the UC Davis Departments of Dermatology, Ophthalmology, Pharmacology, Biochemistry and Molecular Medicine, and the UC Davis School of Veterinary Medicine; Zhejiang University, Hanzhou, China; and the Institute of Molecular Biotechnology of the Austrian Academy of Sciences, Vienna, Austria.

The work was supported by grants from the National Institutes of Health, NSF, American Cancer Society, American Heart Association, Research to Prevent Blindness Inc., and the University of California.