Variety of Guelph projects featured in international journals
From safer bean sprouts to new “sulphur-breathing” microbes to new-employee orientation, a variety of findings by U of G researchers were published this summer. Here's a rundown of some studies reported by faculty and other researchers across campus during the past three months.
SPROUTING A NEW SOLUTION
Bean sprouts, alfalfa sprouts and other types of sprouts contain compounds that reduce the risk of cancer and help lower cholesterol levels. But sprouted seeds have caused at least one outbreak of food-borne illness every year since 1980. A new method to decontaminate sprout seeds ensures that consumers can gain health benefits without worrying about contracting food-borne illness, according to a study reported in the Journal of Food Protection by a research team that includes Prof. Keith Warriner, Food Science.
Even after 600 people in Ontario contracted salmonella from bean sprouts in November 2005 and 6,000 people in Japan fell ill and 13 people died after contracting E. coli 0157 from radish sprouts in 1995, there are still no safety measures in place to ensure pathogen-free sprouts, says Warriner. The bacteria can lodge in tiny seed cracks and are difficult to eliminate during germination. Because most sprouts are eaten raw, they're not exposed to temperatures high enough to kill pathogens.
The team's new sanitizer made of a chemical used in toothpaste and contact lens solutions is harmless to the sprouting seed but lethal to pathogens such as Salmonella and E. coli O157:H7. The team has submitted a global patent for the sanitizer, called Germin-8-or, and its producers are seeking regulatory approval and distributors in North America.
JOB ORIENTATION IMPORTANT
Organizations that offer structured, well-planned orientation programs for new employees are more likely to have motivated, satisfied and committed workers, according to a study by Prof. Jamie Gruman, School of Hospitality and Tourism Management, published in the Journal of Vocational Behavior.
“The bottom line is, the more structure there is around the socialization of new employees — informing them about the kind of training they'll receive and when training will take place — the more likely new employees are to seek information and feedback and view themselves as part of the organization,” he says.
Gruman's survey of undergraduate-level co-op education students found that socialization and programs to integrate new employees can lead to greater employee retention, productivity, commitment and initiative.
New employees are often given a day of intense training and are bombarded with information that they don't understand or remember, he says. This leaves them feeling unprepared to do their job, and they perform poorly as a result.
FEWER STUDENTS TAKING PE
Ontario's high schools offer plenty of physical education classes and intramural and inter-school sports, but fewer than half of students take PE classes after Grade 9 and only a fraction are involved in school sports and recreation programs, according to a U of G study published in the Journal of Adolescent Health.
Student participation in physical activity has declined steadily during the past six years, says Prof. John Dwyer, Family Relations and Applied Nutrition. A specialist in physical activity promotion and a member of Health Canada's Food Guide Advisory Committee, he conducted the study with Kenneth Allison of the University of Toronto.
Dwyer says the finding is part of an alarming trend of inactivity among Canadian youth, which is contributing to an epidemic of obesity and overweight status. Since 1981, the percentage of obese children in Canada has tripled, and less than half of all youth are physically active enough for optimal growth and development. The study highlights the effects of policy on participation in school-based physical activity and the need to promote sports and recreation opportunities for youth outside of school.
NEW MICROBE MAY HOLD CLUES
A new microbe that may hold clues to how life began on a harsh young Earth has been discovered by an international team of scientists, including Prof. Terry Beveridge of the Department of Molecular and Cellular Biology, holder of the Canada Research Chair in the Structure, Physical Nature and Geobiology of Prokaryotes.
In a paper published this summer in Nature, the team says primitive organisms found thriving in extremely hot, acidic conditions may also be important players in cycling crucial elements such as sulphur and iron at deep-sea vents.
It's the first acid-loving archaeon found around deep-sea hydrothermal vents, where minerals released from superheated water support organisms that “breathe” sulphur or metals instead of oxygen. Those conditions are believed to resemble those that nurtured the first life forms on Earth about 3.6 billion years ago.
“We've suspected that microbes there resist strong acids and high temperature, but no one has been able to isolate one,” says Beveridge.
The research team was led by Anna-Louise Reysenbach, a professor of microbial biology at Portland State University and a longtime research collaborator with Beveridge.
MARIJUANA MAY RELIEVE NAUSEA
Prof. Linda Parker, Psychology, has discovered that marijuana may help prevent anticipatory nausea — relief that many cancer chemotherapy patients can't obtain from existing anti-vomit and anti-nausea drugs. Her research was published in recent issues of the journal Physiology and Behavior.
Anticipating nausea and vomiting from chemotherapy, some patients may be deterred from continuing with treatment, says Parker, who was appointed to a Canada Research Chair in Behavioural Neuroscience this summer. “Known antiemetic drugs aren't effective in treating this learned nausea.”
In her study, she learned how two compounds found in marijuana –– THC (marijuana's high-inducing chemical) and cannabidiol –– can treat vomiting and nausea.
“People report that if they smoke marijuana before they go for chemotherapy treatment, they don't experience the anticipatory nausea or vomiting,” says Parker, whose collaborator — Raphael Mechoulam of the Hebrew University in Jerusalem — discovered THC.
SENIORS NEED GOOD NUTRITION
Allowing vulnerable elderly adults to look after their own nutrition may leave them at much greater nutritional risk, says Prof. Heather Keller, Family Relations and Applied Nutrition. Her studies published in the Journal of the American Dietetic Association and the Journal of Nutrition Health and Aging found that meal assistance programs such as Meals on Wheels, family support systems and formal nutrition programs help prevent malnourishment in elderly adults.
“Nutrition risk is found to predict mortality and health-related quality of life, so it's extremely important to find ways to help vulnerable seniors improve their food intake,” says Keller. “By providing a hot meal a day, you do actually improve the food intake of an individual.”
She also found that vulnerable elderly adults with access to family members had better diets than did seniors without family support.
ECOLOGICAL FOOD WEBS AT RISK
Even as biodiversity comes under increasing threats from human activity, a new study by U of G researchers published this summer in Nature reveals that the stability of ecological food webs is also at risk.
The study, headed by post-doctoral researcher Neil Rooney and Prof. Kevin McCann, Integrative Biology, says complex ecosystems are held together by their top predators — the very species most under threat from humans.
“It's an important finding,” says Rooney. “It indicates that top predators keep food webs in check and that if you remove them, the systems will unravel.”
The team surveyed data from eight aquatic and terrestrial ecosystems across the world, including Chesapeake Bay, the Alaskan tundra, a European pine forest and a Dutch experimental farm.
Nutrient pollution from urban development or intensive agriculture can affect food webs, resulting in a loss of both diversity and stability, says Rooney. And removing a top predator such as tuna can harm an entire food web through its effects on everything from prey fish species to plankton. Predators — commonly dominant carnivores — are often more susceptible to human activity than other members of the food web.
INSURANCE RATES NEED NOT VARY
Instead of charging people different insurance rates based on their risk factors, insurance companies still come out ahead by charging everyone the same price, according to research by a U of G economist published in The Geneva Papers.
“Most people in the insurance industry believe you should charge people who have different actuarial costs different prices and to not do so is discriminatory,” says Prof. Mike Hoy. “But I have a mathematical theorem that shows the equity benefits of charging everybody the same price could well outweigh the efficiency problem of doing so.”
Hoy's theory says if factors are based on things like genetic diseases, which affect only small groups of people, charging everyone the same amount shouldn't be a detriment to insurance companies.
More analysis needs to be done to determine exactly how small of a high-risk group is “small enough” to charge everyone the same premiums, but it's safe to assume smaller variables like genetic tests will produce favourable results, he says.
