Five candidates will present seminars in Briggs Hall, UC Davis campus, for the two U.S. Department of Agriculture (USDA) honey bee positions open at the USDA facility, located on Bee Biology Road, next to the Harry H. Laidlaw Jr. Honey Bee Research Facility.
Paul Pratt, the selection committee chair, is the research leader for the Invasive Species and Pollinator Health Research Unit, Western Regional Research Center of the Agricultural Research Service, USDA, in Albany, Calif.
Seminars will be presented in 122 Briggs from 10 to 11 a.m. followed by a group faculty meeting (UC Davis Department of Entomology and Nematology) in Briggs 366 from 1:30-2:15 p.m.
Tuesday, Dec. 11:
Natalie Boyle: “Promoting Pollinator Health and Safety in Agroecosystems”
Wednesday, Dec. 12
Michael Smith: "How Does a Bee Detect her Colony's Size?”
Thursday, Dec. 13:
Julia Fine: "Inside the Brood Box: Using Novel Methods in the Study of Honey Bee Reproduction”
Friday, Dec. 14:
Arathi Seshadri: “The Role of Behavioral and Nutritional Factors in Honeybee Health”
Monday, Dec. 17:
Clint Otto: "From Landscapes to Flowers: Understanding Forage in America's Last Beekeeping Refuge”
Professor Karban of the Department of Entomology and Nematology, who has maintained a study site at Bodega Marine Reserve in central California since 1982, links the decrease to temperature.
“I've been surveying seaside daisies for spittlebugs at Bodega Bay every spring for the past 35 years and found that the number of these highly visible and previously widespread insects was related to temperature,” Karban said.
However, since the spring of 2006, the UC Davis researchers have found no spittle masses on the Bodega Bay Reserve's coastal prairie. Other researchers have also detailed how sensitive spittlebugs are to environmental conditions.
The meadow spittlebugs, Philaenus spumarius, thrive in cool, moist habitats and suck plant juices, feeding on xylem fluid and excreting most of it as a foamy white mass known as spittle. The mass protects them from desiccation, predation and parasitism. In past years, Karban and Huntzinger found an abundance of meadow spittlebugs feeding onseaside daisy (Erigeron glaucus) and the non-native ice plant (Carpobrotus edulus).
The Karban-Huntzinger research paper, “Decline of Meadow Spittlebugs, a Previously Abundant Insect, Along the California Coast,” is especially important in light of alarming research in Germany dubbed “Insect Armageddon.” In that research, published last October in the journal PLOS ONE, German scientists investigated aerial insect biomass across 96 protected preserves in the country. They found that three-quarters of flying insects had disappeared over the past 25 years.
The earth's climate is warming at a rate of 0.2 degrees Celsius per decade over the past 30 year, according to the National Aeronautics and Space Administration. California's coast has also experienced climate change; the recent severely hot years in the state have also been severely dry. Models of future climates predict that the warming trend will continue and that variability in conditions, for example, droughts, also will increase in frequency and severity.
“Whether the altered climates we face globally will change our ecological communities will depend on how able individual species are to adapt to the new conditions,” the UC Davis researchers explained. “Since meadow spittlebugs were widespread and abundant, we might have assumed that they would not be threatened by climate change. What we have found is that even this species has not been able to adjust physiologically or ecologically. If the pattern they show is common, we may also see surprising changes in the abundance or distribution of other insects as well. These changes are likely to have dramatic and unexpected effects on the functioning of ecosystems.”
Casida, 88, one of the world's leading authority on how pesticides work and their effect on humans, died June 30 of a heart attack in his sleep at his home in Berkeley. He was considered the most preeminent pesticide toxicologist over at least the last two centuries.
A distinguished professor emeritus of environmental science, policy and management and of nutritional sciences and toxicology, Casida was the founding director of the campus's Environmental Chemistry and Toxicology Laboratory.
When awarded the Wolf Prize in Agriculture in 1993, the Wolf Foundation lauded his “research on the mode of action of insecticides as a basis for the evaluation of the risks and benefits of pesticides and toxicants, essential to the development of safer, more effective pesticides for agricultural use." according to a UC Berkeley News Service story. "His discoveries span much of the history of organic pesticides and account for several of the fundamental breakthroughs in the fields of entomology, neurobiology, toxicology and biochemistry.”
Former graduate student Bruce Hammock, now a distinguished professor at the University of California, Davis, who holds a joint appointment with the UC Davis Department of Entomology and Nematology and the UC Davis Comprehensive Cancer Center, remembers him as a “lifelong mentor who evolved into a colleague and a friend.”
“John continued his high productivity until his death with major reviews on pesticides in 2016, 2017, and 2018 in addition to numerous primary papers,” Hammock noted. “He was working on primary publications as well as revising his toxicology course for the fall semester at the time of his death. Pesticide science was the theme of his career, and we live in a world with far safer and more effective pest control agents because of his effort.”
John Casida opened multiple new fields ranging from fundamental cell biology through pharmaceutical discovery. "He pioneered new technologies throughout his career, from being one of the first to use radioactive compounds for pesticide metabolism through studies with accelerator mass spectrometry, photoaffinity labeling and others," Hammock related. "Yet the greatest impact of his career probably lives on in the numerous scientists he trained, now carrying on his traditions of excellence in science. These scientists are around the world in governmental, industrial and academic careers.”
As compiled and shared by Hammock, below are comments from a few of his doctoral students and postdoctoral fellows who worked both with Casida at UC Berkeley and at, least for a time, also were at UC Davis.
Distinguished Professor of Cell Biology and Neuroscience, University of California, Riverside
"This project also allowed me to build a long lasting friendship with Bruce Hammock who also was on the same project. Since John was always very focused, I often challenged John's patience with my practical jokes. I am sure he knew who the culprit(s) were but he never revealed he knew.
“The research experiences in John's lab made an indelible impression on me that drove me to return to the United States from Malaysia for an academic career in the UC system. Personally, I have lost an incredible mentor, and the scientific community lost the most preeminent pesticide toxicologist in the last two centuries. John changed the way we investigated mechanisms of toxicity at all levels. I certainly will miss him dearly.
Distinguished Professor at the University of California, Davis: Joint appointment with the Department of Entomology and Nematology and the UC Davis Comprehensive Cancer Center
"After telling him I was there to be his graduate student, he replied he had no money for students. My retort was that I had a fellowship. He then told me that students were not space effective, and I promised not to take up much space. He continued that students were not time effective, and I promised not to take his time. In retrospect, Sarjeet must have really soured him on graduate students a few hours earlier."
"Months later, Sarjeet and I were sharing a desk-lab bench in the windowless closet next to the 'fly room' when Dr. Casida walked in. He had noted we both listed him as our major professor and asked if there was anything, he could do to encourage us to leave. When in unison we replied 'No!,' he politely left without accepting us, but soon we both had a desk and bench.
"So a few paces after Sarjeet, I initiated the most thrilling four years of my life. John's introduction to experimental science was marvelous with the perfect balance of inspiration, instruction and tremendous freedom. I was privileged to learn from a wonderful group of individuals and, of course, I made my most enduring of friendships with Sarjeet Gill. In addition to science, John taught a life-family-science balance by example. John was my life long mentor in science and in life but also evolved as a colleague and friend.
"Three more delightful years passed and John then took me to lunch at the faculty club. As I was about to leave the laboratory for the U.S. Army, he gave me sagely advice such as he had had it easy during the Sputnik period and I would have it hard. Then he went on to tell me than most people in the laboratory did not find my practical jokes nearly as funny as I did. I did not reveal that Sarjeet had both planned and executed most of them. Thus, Sarjeet succeeded in disrupting my Berkeley career from beginning until the end.
"John and his laboratory at Berkeley provided me with the most exciting years of my scientific career. In his own work, John moved from strength to strength creating numerous entire fields along the way. His scientific insight and drive were a constant stimulation to drive for innovation and excellence. Whenever I had an opportunity, I encouraged others to join his team. John was an inspiration and role model, not only because John came in early and stayed late, but also because he did science for the fun of discovery and taught for the joy of teaching."
Keith Wing Consulting LLC
Life Science Industrial Biochemistry or Biotechnology
"While we all worked hard including many evenings and weekends, there were times when I or other American rebels would lead a mass lab exodus for a salmon fishing or ski trip during (gasp!) regular business hours. John would pretend to barely notice our ill-disguised escape along the cabinets that lined the Wellman Hall basement, except to raise his right eye from his manuscript editing in an unmistakable sign of disapproval at our lack of scientific drive.
"And this leads to another Casida work pattern of the time…. All of us scientists were subject to John's multiple cycles of manuscript editing. We would wrack our brains trying to put the right words and figures down as manuscript drafts, submit them to John, and wait for three days or less for him to return it to us in a sea of thin red ink, and the humbling realization that we really were much poorer writers than we'd thought. After discussion with John and acquiescing to practically every edit he'd made, the manuscript would be re-typed manually by his administrative assistants in entirety and the cycle would repeat but with less red ink. After at least three cycles of this, we'd submit the manuscript for publication, often with a high acceptance rate. With time, we all came to understand and see John's wisdom in approaching publication and science contribution. All of this occurred right as word processing programs had started taking hold in the outside world, and perhaps my one service to the lab on my 1983 exit was to convince John to look into using word processing/saving documents on disks for editing. Oh, and maybe a bit of science as well.
"John Casida's lab has been the world leader in examining both pesticide metabolism and their biochemical target sites. I was lucky enough to work on a project that combined both, and it molded the way I looked at insecticide discovery in industry. The interdisciplinary approach to the mechanisms by which xenobiotics interface with biological systems influenced the thinking of every person who has passed through John's lab. That influence has proliferated throughout the world and has advanced the field of pesticide toxicology to what it is today. We mourn the loss of a great leader but understand that his alumni are a large international family that will carry his spirit and teachings forward."
Andrew 'Andy' Waterhouse
Director of the Robert Mondavi Institute for Wine and Food Science and Professor of Viticulture and Enology,
University of California, Davis
"A couple of weeks after I arrived, he showed me Don Crosby's book on natural toxicants, and asked if I would confirm the very high toxicity of ryanodine mentioned therein. The high toxicity suggested strong binding to a key regulatory protein, and its novel and unknown mode of action made it an exciting prospective target. Confirming that ryanodine was in fact a deadly toxic, he set a project in motion to discover the site of action, hiring Isaac Pessah to use the yet-to-be-made radioligand on a hypothetical site of action!
"We were astonishingly lucky to find that the natural source of ryanodine contained a major impurity that was one step away from the highly radioactive form, so it wasn't too long before we had very hot ryanodine available. Initial attempts detected no binding at all, but Isaac thought to add some calcium to the assay, and we had the binding site in hand! This discovery essentially established a field of science in muscle physiology and pharmacology, with entire symposia dedicated to exploring this binding site and its broader significance to toxic modes of action. Isaac is an established leader in the field. It was a real privilege to see how groundbreaking research can happen and be part of it, and to get to know all the fabulous scientists that John collected around him."
Associate Dean of Research and Graduate Education, and Professor, Department of Molecular Biosciences, UC Davis School of Veterinary Medicine
University of California, Davis
"I remember most vividly my reaction when John also indicated that working on the biochemistry GABA receptors, my original intent for traveling across country for a postdoc, was not to be. ‘Work on something else' John advised, ‘there are so many interesting unanswered questions around the PCTL.' Arguably John's straightforward and highly insightful advice changed the course of my professional life. He introduced me to chemist Andy Waterhouse, and the next two years of work that led to the discovery and identity of the ryanodine receptor were breathtaking. Our discovery benefited from many factors; a gift from Ryania speciosa in the form of didehydroryanodine, which Andy identified, the newly published use of palladium catalyst to catalyze efficient reduction of minute quantities of unsaturated bonds, the National Tritium Laboratory just above the PCTL…and of course, there was John's unwavering support for discovery, no matter how risky. Successful synthesis of [3H]ryanodine and identity of its receptor paved the way to immense basic discoveries in virtually every field of science, identification of several disease causing mutations of skeletal and cardiac muscle and the nervous system, and successful discovery of highly selective ryanoid insecticides. Since the first paper published in 1985, there have been nearly 20,000 peer reviewed publications (ISI Web of Science) and a search on Google Scholar yields more than 70,000 hits. To many, John was the recognized leader in pesticide chemistry and toxicology. I agree, although from my perspective, John was also a true renaissance individual, seeding ideas of great significance in so many fields, of which ryanodine receptors represents only one of many. His love of science and discovery positively impacted his students and postdocs. He will be fondly remembered and sorely missed.'
Professor, Department of Molecular Biosciences and Bioengineering College of Tropical Agriculture and Human Resources, University of Hawai‘i at Mānoa
" In April 2018, I had a couple of telephone conversations with Professor Casida. He shared with me what he was doing (of course, writing manuscripts), his health, Kati's health, his sons and his grandkids. We talked about meeting at the Biochemistry and Society: Celebrating the Career of Professor Bruce Hammock, to be held in Davis in August 2018. We talked about a possibility to attend a meeting together in China in 2019.
"I was privileged to manage Professor Casida's manuscript entitled 'Pesticide Detox by Design' that he submitted to the Journal of Agricultural and Food Chemistry. This is Professor Casida's last manuscript, I believe. It is still in the review process. He wrote that 'Detoxification (detox) plays a major role in pesticide action and resistance…' A reviewer who reviewed the manuscript wrote me “I just heard that Professor Casida has passed away... Professor Casida was a giant in pesticide science, a special and unique person. It is a great loss to the pesticide science community…”
Professor Casida is survived by his wife, artist and sculptor Kati Casida, sons Mark and Eric Casida, and two grandchildren.
- John Casida Obituary, UC Berkeley News Service
- For the Fun of Science: A Discussion with John E. Casida (Archives of Insect Biochemistry and Physiology)
- Still Curious: An Overview of John Casida's Contributions to Agrochemical Research (JAFC)
- Curious about Pesticide Action, by John E. Casida (JAFC)
In fact, it was her childhood curiosity about a yellow fever vaccination that sparked her interest in mosquitoes.
In her youth, Olivia traveled with her parents and brothers to “off-the-beaten-path” locations. “So I was exposed to vector-borne disease awareness from a young age,” she recalled. “When I was 8 years old, I remember getting the yellow fever vaccination and being curious about why I had to get it for a trip to Southern Africa. I think that was my defining moment when I learned mosquitoes are more than just annoying. Since then, I've slept under many mosquito nets and am no stranger to mosquito bites.”
“I didn't think much about making a career out of those 'skeeters, though. I attended Cornell University as undergraduate, where I studied global public health from multiple perspectives. It wasn't until I became a research assistant in Dr. Laura Harrington's lab that I became fascinated with mosquito biology and decided to pursue a career in medical entomology.”
Winokur, who received her bachelor's degree in 2015 from Cornell University, majoring in Interdisciplinary Studies and focusing on the environmental effects on human health, enrolled in the UC Davis graduate program in 2016 as a Ph.D entomology student with a designated emphasis in the biology of vector-borne diseases.
She studies with major professor and UC Davis alumnus Christopher Barker, associate professor and associate researcher in the Department of Pathology, Microbiology and Immunology, School of Veterinary Medicine, who doubles as a graduate student advisor in the UC Davis Department of Entomology and Nematology.
Earlier this year, Winokur received a three-year National Science Foundation Graduate Research Fellowship. A 2017 Bill Hazeltine Memorial Award also helps fund her research.
A typical day in the lab: “My days are usually a bit all over the place--I typically spend some time in the BSL-3 (Biosafety Level 3) either collecting samples from infected mosquitoes or processing previously collected samples, some time back in the lab analyzing data and writing, and I'm still taking classes so a few days a week I spend the afternoon on the main campus.”
Born in Long Beach, Calif., Olivia grew up in Laguna Niguel, Calif., where she focused on science as a part of the Dana Hills High School Health and Medical Occupations Academy. Olivia also played basketball at Dana Hills and helped the team win its first league title.
What drew her to UC Davis? “I grew up in California so I was familiar with UC Davis from a young age. I actually applied to UC Davis as an undergraduate, but decided to try life on the East Coast instead and attended Cornell University. While at Cornell, I learned a lot about UC Davis as most of my professors had spent some time at UC Davis during their academic tenure, and a lot of the research I was reading was coming out of UC Davis. I was excited to come back to the West Coast for graduate school so UC Davis seemed like an obvious choice!”
While at Cornell, she interned at the National Institutes of Health (NIH) in 2014, when advised by John Balbus of National Institute of Environmental Health Sciences (NIEHS), and Joshua Rosenthal, Fogarty International Center, where she coordinated and wrote an interagency proposal for climate change mitigation in middle and low-income countries under the United Nations. "I also helped develop a global clean cook stove implementation framework to advise NIH initiatives,” she said.
Winokur is a co-author of “The Impact of Temperature and Body-Size on Flight Tone Variation in the Mosquito Vector Aedes aegypti (Diptera: Culicidae): Implications for Acoustic Lures," published in April 2017, in the Journal of Medical Entomology. Several other manuscripts are accepted or in preparation.
She has given presentations at the Mosquito and Vector Control Association of California and the American Society of Tropical Medicine and Hygiene.
Dedicated to helping high school girls transition into STEM (Science, Technology, Engineering and Math) careers, Winokur is a founding board member and publicity co-chair of GOALS (Girls' Outdoor Adventure in Leadership and Science). The organization seeks “to cultivate and embolden the next generation of STEM leaders through a free, immersive, field-based summer science program for high school girls.”
“GOALS is for high school girls, inclusive of cis, trans, and gender nonbinary youth who identify with girlhood, to learn science hands-on while backpacking through the wilderness,” Winokur related. “I have worked with an incredible team of UC Davis affiliates to create GOALS to increase opportunities for high school students who identify with girlhood from backgrounds traditionally underrepresented in STEM. Our first trip is happening this summer!” This year's program takes place July 21 to Aug. 5.
Winokur is also a part of the Letters to a Pre-Scientist program “so I get to be a pen-pal to an elementary school student to talk about science!” In addition, she serves as the treasurer of the UC Davis Entomology Graduate Student Association.
Delighted to return to California after being on the East Coast, Winokur spends her leisure time outdoors hiking and backpacking “and exploring the beautiful places near Davis like the Lake Tahoe area and Yosemite. I taught backpacking and wilderness survival skills for Cornell Outdoor Education during college. Additionally, I'm a trivia nerd so I watch a lot of Jeopardy! and play pub trivia with my entomology colleagues weekly. I also enjoy drawing, reading, playing board games, and doing jigsaw puzzles. When I get the chance I enjoy traveling as well--I just returned from Belize and I'll be in Denmark in July!”
After finishing her Ph.D., Winokur plans to remain in academia, but “I'm unsure exactly what that will look like! I really enjoy research, teaching, and mentoring so I'd like to have a career where I can do all of these. I also plan to have a career where I can conduct translational research with broad global health implications, engage non-scientists, create tools to help decision makers mitigate vector-borne disease burden worldwide, and encourage interest and diversity in STEM.”
The grant, “Food Quality in Egypt: Screening for Contamination with Pesticides using Innovative VHH Antibody-Based Assays and Biosensors,” was one of 15 collaborative projects selected for funding by the U.S.-Egypt Science and Technology Joint Board. The grants foster research collaboration between Egyptian and U.S. scientists.
“Zagazig is one of the world's premier agricultural institutions,” said Hammock, a distinguished professor who holds a joint appointment with the UC Davis Department of Entomology and Nematology and the UC Davis Comprehensive Cancer Center. “I am thrilled to have this support to expand our long collaboration with Zagazig. This is very practical work with potentially profound outcomes on reducing exposure of consumers and workers to pesticides. We are using a very sophisticated new antibody technology to allow on site monitoring of potentially dangerous pesticides.”
“Our postdoctoral scientist Natalia Vasylieva is the star on the project,” Hammock said, “but it encompasses our entire immunoassay group. We have a long-term collaboration with Zagazig University.”
The grants are funded by the National Academies of Sciences, and the Egyptian Science and Technology Development Fund. Reviewers evaluated the proposals' scientific and technical merit, relevance to program objectives, capabilities of partner institutions and individuals, nature of collaboration, and cost-effectiveness. The board funded less than 12 percent of the eligible proposals.
“Immunoassay (ELISA) is an alternative and complimentary analytical method to instrumental techniques like liquid or gas chromatography,” said Vasylieva, who leads the immunoassay group in the Hammock lab. A native of the Ukraine, she received her master's degree from Taras Shevchenko National University of Kyiv, Ukraine, and her doctorate from National Institute of Applied Sciences in France. Joining the Hammock lab in May 2013, she focuses her research on development of nanobodies as neutralizing agents for small molecule poisoning, as well as use of nanobodies as therapeutics.
“ELISA is also considered cheaper method,” said Vasylieva. “Particularly, ELISA is economically interesting when relatively large set of samples have to be analyzed. This is usually the case in the environmental monitoring for contamination and human exposure studies.”
The Hammock lab, which has extensive experience in development of immunoassays, extends the field by developing new formats of the immunoassays by developing new reagents. “In particular, we develop new type of antibodies, called nanobodies or VHH (from variable heavy domain from heavy chain only antibodies) that naturally occur in camelids and sharks,” Vasylieva said. “These antibodies have all the affinity properties of conventional (polyclonal and monoclonal) antibodies, but also have unique properties, like small size (1/10th of the size of conventional antibodies), high thermal stability, resilience to organic solvents and high refolding capacity. These properties make them particularly suitable for use in portable devices for environmental and human exposure monitoring.”
A large amount of pesticide is used in Egypt,” she said. “So far, only limited amount of information is available about environmental contamination and human exposure to those pesticides. In these few publications available, levels of pesticide in the food appears to be over the allowed limits.”
In their abstract, the researchers explained that long-term application of pesticides has resulted in contamination of food in Egypt. “Continuous exposure to pesticides is usually associated with infertility, birth defects, endocrine disruption, neurological disorders and cancer in humans. Worldwide reliance on chemical pesticides in agriculture remains an essential component for high food production. According to the Egyptian Agricultural Pesticide Committee, the amount of pesticides imported and used for agricultural production has more than doubled from 2005 to 2012. However, only a few studies have been published on this subject over the past 10 years and they show high levels of pesticides in a variety of food products.”
“Food monitoring studies in Egypt have been primarily limited to analysis of organochlorides, organophosphates, and carbamate insecticides,” the researchers noted in their abstract. “Research and monitoring of other pesticide groups is a relatively new subject, and a knowledge gap still remains. With this study, we propose to assess the safety of food available on the Egyptian market and develop tools for fast and low-cost contamination screening. Our long-term goal is to contribute to a healthier Egypt by raising awareness about food chemical safety and to provide simple tools for researchers and stakeholders to screen the food products for compliance with regulatory policies. We hypothesize that human exposure to toxic chemicals through contaminated food (domestic and imported) has increased due to excessive application of pesticides in order to face nutrition needs.”
They defined three specific goals of the project:
- To screen Egyptian domestic and imported food samples for pyrethroid insecticide residues, a major group of insecticides used today, using immunoassays;
- To develop new reagents and immunoassays for detecting diamide insecticides, a group of pesticides whose use is rapidly growing, and
- To develop tools for fast and low-cost food contamination screening in the environment with minimal technical support.
Overall, the scientists aim to develop innovative immunoassays and biosensors empowering scientists and engaged Egyptian communities to collect analytical data to address environmental chemical concerns. “We will do this by adapting and refining technologies to improve assay performance, reliability and field portability,” they wrote. “The knowledge gained from this research will provide insight into human exposure to agricultural pesticides in Egypt and will raise the Egyptian population's awareness of food quality.”
Hammock, a member of the National Academy of Sciences and the National Academy of Inventors, directs two major UC Davis programs; the Superfund Program financed by the National Institute of Environmental Health's National Institute of Environmental Health Sciences (NIH-NIEHS); and the NIH Biotechnology Training Program. Hammock, who holds a doctorate in entomology/toxicology from UC Berkeley, served as a public health medical officer at the U.S. Army Academy of Health Science in San Antonio, Texas; a postdoctorate fellow in entomology/toxicology at UC Berkeley; and a postdoctoral fellow in biochemistry with the Rockefeller Foundation, Northwestern University, Evanston, Ill., before joining the UC Davis faculty in 1980.