Login with your Social Account

Scientists study how wasps learn for better trap

Scientists study how wasps learn for better trap

On lingering warm fall days, hungry wasps are often unwelcome guests at picnics and tailgates, homing in on hamburgers and buzzing bottles.

It’s worse in parts of the southern United States, where paper wasp species swarm air traffic control towers and other tall, solitary buildings during fall mating season.

Scientists at Washington State University aim to take the sting out of these encounters. Partnering with the U.S. Department of Defense, WSU entomologists are studying wasps’ ability to learn and respond to chemical signals, with the goal of building a better paper wasp trap.

Hungry, unwanted visitors

The European paper wasp, Polistes dominula, gains its name from the paper it makes to build its umbrella-shaped nests, often found under eaves across North America.

While less aggressive than their yellowjacket cousins, from whom they subtly differ in appearance, paper wasps will deliver a painful sting if their nests are threatened.

Paper wasps will occasionally feed on nectar and fermenting substances, but also prey on insects as a protein source for their young. That makes human food especially attractive as summer ends and insect prey, such as aphids and caterpillars, become rare.

Megan Asche holds a vial containing a paper wasp.

Doctoral student Megan Asche views captive wasps in a vial at her WSU lab.

“They’re looking for protein and sugar,” said Megan Asche, a WSU Department of Entomology doctoral student. “That’s why they show up at your house, zoom around your garbage can, and take a bite out of your sandwich.”

Paper wasps can be hard to eliminate from homes and yards, because they’re different from other wasp species.

“They’re not attracted to the same things that yellowjackets and hornets are,” Asche said. “We’re trying to find something that works better for these animals—a better wasp trap.”

Buzzing the control tower

Funded by a five-year, $366,000 Department of Defense grant, Asche’s research is spurred by an annual wasp invasion of military airstrips in the southern U.S.

Like many flying insects, paper wasps seek a preferred place to mate. Drones look for queens at places called hill-topping sites: “Basically a really tall thing surrounded by flat, open space,” Asche said. “An air control tower is exactly what wasps are looking for.”

The presence of thousands of wasps in and around the tower, crawling on radar screens and personnel, makes the job of air traffic controllers much harder.

“We need to figure out what we can use to attract wasps away from the towers,” Asche said.

Can wasps learn?

Paper wasps tending a growing nest.

Paper wasps tending a growing nest. Swarming during fall mating season, wasps can pose a challenge at air traffic control towers (Photo by Megan Asche).

To do that, she is studying wasps’ ability to learn and react to chemical signals.

“Wasps are a lot more flexible in their behavior than most insects,” Asche said. “They eat a lot of different foods, plants, and animals, so they’re capable of adjusting to their environment and changing their routine.”

In Asche’s lab, wasps are put into a flight tunnel—a large see-through plastic box with electric fans on both ends. Near one end is a nozzle emitting scent, either extracted from flowers or isolated from the wasps themselves.

Wasps are released one at a time into the tunnel, and Asche carefully notes how they react to the scent.

“That’s a perfect flight!” Asche remarked as one male wasp was put through the paces. He soon reacted to the odor, questing and landing near the nozzle’s tip.

“I’m trying to see how quickly they can learn,” she explained. “If we understand how they learn, we can teach them to associate an odor with food, and replace it with a working trap.”

Deciphering wasps’ chemical signals

Asche and other WSU entomologists are also exploring the chemistry behind wasp reactions. They are isolating and identifying the compounds they use to communicate and congregate.

The team has had surprising success using synthetic lures to successfully trap and remove wasps, both in Washington state and the southern U.S.

“Paper wasps are a beneficial part of our ecology, but they don’t belong in our buildings,” Asche said. “For people who don’t want to interact with wasps, our research could really bring peace of mind.”

Materials provided by Washington State University

Natural ways to avoid the heat

Natural ways to avoid the heat

Cranking up the air conditioner isn’t the only way to deal with the stifling heat that is blanketing much of North America and Europe.

Washington State University architect Omar Al-Hassawi is an expert at reducing indoor temperatures without the use of electricity.

His research blends ancient architectural practices with modern innovations to produce surprising results.

Whether you lack an air conditioner or are trying to cut your utility bill, Al-Hassawi can help. Here are a few of his suggestions for beating the heat this summer.

Ventilation strategies

In a climate like the Inland Northwest where temperatures drop by 30-35 degrees Fahrenheit at night, natural ventilation is an effective alternative to blasting the air conditioning.

Opening home windows after sunset and leaving them open until about 10 a.m. the next morning will help flush out the heat generated indoors the day before, Al-Hassawi said.

Conversely, closing windows during the hottest time of the day, from around noon till about an hour before sunset, will minimize heat gain.

Proper shading techniques

Another useful strategy for keeping home temperatures cool is shading exterior windows from the outside instead of the inside with blinds, curtains or even foliage.

“This acts like a hat for the windows similar to how we use hats to shade and protect ourselves,” Al-Hassawi said. “Exterior shading for windows facing south and west is especially effective.”

Home occupants can also wear very light clothing and avoid high heat-generating activities such as intense exercising and cooking meals during the afternoon. A cold shower or placing some cool water in front of a low flow fan are also good ways to create evaporative cooling and reduce indoor temperatures.

No stranger to the heat

Headshot of Omar Al-Hassawi
Omar Al-Hassawi

Al-Hassawi grew up in Iraq where temperatures rarely dip below 110 degrees Fahrenheit in summertime. For hundreds of years, people in the region incorporated downdraft and evaporative cooling techniques into their architectural designs that harnessed the power of wind and water to keep inside temperatures bearable.

Tall, hollow towers were often placed at the corners of homes to direct breezes down and let warm air escape. Often times, a pool of water would be placed at the base of the towers. As the air flowed over the water, it would evaporate and the air would absorb moisture, becoming cooler before passing into the home. Al-Hassawi said interest in adopting these passive cooling techniques in places like the United States has been on the rise in recent years as annual summer temperatures continue to increase across the country.

“Humans have been using architectural designs and other natural techniques to keep their homes cool for a very long time,” Al-Hassawi said. “We are starting to see a rebirth of a lot of these techniques which is a great thing considering the large role the building sector plays in global warming.”

One idea is to modify the wind tower concept by placing the evaporative cooling mechanism at the top of the tower instead of at its base. As warm air passes into the top of the tower, it would cool down because of the increase in moisture from the water. Then, the cool air would become heavier and drop naturally into the building by gravity.

“The tests I’ve done show that incorporating this type of cooling system into modern homes, particularly in a place like the Pacific Northwest, could bring temperatures down by as much as 30 degrees,” Al-Hassawi said. “So, if it is 100 F outside you can get 70 F inside.”

Materials provided by Washington State University

Cutting-edge needles promise more accuracy in medical procedures

Cutting-edge needles promise more accuracy in medical procedures

Scientists at Washington State University are creating waterjet-based, steerable needles that could give doctors more accuracy and control and reduce tissue damage in many common, non-invasive medical procedures.

John Swensen, an assistant professor in the School of Mechanical and Materials Engineering, and graduate students Mahdieh Babaiasl and Fan Yang were part of a WSU team that recently co-authored a paper on steerable needles, which was published in the 2019 International Symposium on Medical Robotics (ISMR)

“Our needles have the potential to improve treatments that you can’t reach with traditional straight needles,” Babaiasl said.

For many medical procedures, doctors would like to have bendable, steerable needles to get to their targets. In fact, in a little trick of the trade, doctors will sometimes bend their needles by hand when trying to access a tricky spot, such as when giving a nerve block for back pain. Another problematic procedure for doctors is liver biopsies. When the area to be biopsied lies under the lungs, for instance, the needle must go through the chest cavity.

Waterjet technology has been used for decades in many industries, such as mining and manufacturing.

Swensen’s team developed a technology that uses a controllable waterjet nozzle at the tip of the needle to delicately cut through tissue. After the tissue is cut by the water jet, the bendable, flexible needle can follow the tissue fracture to its destination. In their study, the researchers looked at how the waterjet-based system performed using different nozzle widths, water pressures, and with different tissue stiffness. They recently filed for a patent.

Researchers testing a waterjet-based steerable needle. Their technique could decrease time taken for procedures, in some cases reducing the time taken for procedures by more than half. In addition, the accuracy generated by this technology means the needles can cut through tissue while keeping surrounding blood vessels intact.

In addition to allowing doctors to make turns, the waterjet needles create less friction than straight needles and cause less buckling of the needle and tearing of the surrounding tissue. Check out a video of the needle in action.

In the future, a nurse or doctor sitting in another room could control the needles with something like a video game console, Swensen said.

“Such needles also reduce the need to have precise manual hand-eye coordination,” he added.

Swensen and his team are currently testing their needle technology on artificial tissue made from an elastic polymer that mimics many of the physical properties of biological tissues and will soon begin experiments on real tissue.

Materials provided by Washington State University

Titan VanCoug now in bloom

A Rare Corpse Flower now in bloom at the WSU campus

After 17 years, a rare corpse flower housed at Washington State University Vancouver is finally blooming for the first time.

Titan VanCoug, as it is known on campus, began to bloom just before 8 p.m. Monday, July 15 outside the greenhouse at the east end of the Science and Engineering Building.

The bloom is expected to last 24 to 48 hours and can be seen in person 8 a.m.– 9 p.m. on the WSU Vancouver campus or via live webcam anytime.

About the corpse flower

The corpse flower (Latin name Amorphophallus titanum, also known as titan arum) is infamous for its odor—comparable to that of a decomposing animal.

The odor is meant to attract pollinators and help ensure the continuation of the species. Dung beetles, flesh flies and other carnivorous insects that typically eat dead flesh or lay their eggs in rotting meat are attracted to the titan arum. In the corpse flower’s native Sumatra, the bloom can be located by smell from up to 50 yards away. Sometimes it is so strong people can’t stand to be near it.

Corpse flowers are among the world’s largest and rarest flowering structures. They bloom rarely—typically after seven to 10 years of growth and just once every four years or so afterward throughout a 40‑year expected lifespan.

About Titan VanCoug

Titan VanCoug has been raised by Associate Professor of Molecular Biosciences Steve Sylvester. He planted a seed from the University of Wisconsin-Madison’s titan arum plant, affectionately named Big Bucky, in 2002. He cultivated it in a pot on his desk until it grew too large to contain in such a small space. It has grown in a stairwell in WSU Vancouver’s Science and Engineering Building for some time.

On June 1, Titan VanCoug’s first bloom started to appear. By July 1, Titan VanCoug had grown to 25.5 inches tall. It has grown about 2 inches per day leading up to its bloom.

A late bloomer at 17, Titan VanCoug’s first bloom was most likely delayed because its corm (tuber) cloned itself. Corpse flowers put up only one leaf at a time. The pot that contains Titan VanCoug has had as many as four leaves showing at once.

Sylvester has arranged to receive pollen from The Royal Botanic Garden Edinburgh. He hopes to pollinate Titan VanCoug so that it will develop seeds he can share with other universities and conservatories.

Materials provided by Washington State University

asteroids

Asteroid tracking software updated to be 25 times faster

Modeling the shape and movement of near‑Earth asteroids is now up to 25 times faster thanks to new Washington State University research.

The WSU scientists improved the software used to track thousands of near‑Earth asteroids and comets, which are defined as being within 121 million miles or about 1.3 times the distance to the sun.

Their work provides a valuable new tool for studying asteroids and determining which of them might be on a collision course with Earth.

Matt Engels, a Ph.D. student who has been working with Professor Scott Hudson in the School of Engineering and Applied Sciences at WSU Tri‑Cities, is the lead author of a paper on the research in the July issue of Astronomy and Computing.

Researchers would like to have better information on asteroids, including which of them might crash into earth. The rocks also can provide valuable scientific information, answering fundamental questions about the creation of our solar system and providing a glimpse into our planetary past. Knowing more about individual asteroid composition also could open up new opportunities for possible asteroid mining.

NASA maintains a catalog that includes information on more than 20,000 near‑earth asteroids and comets. In the mid‑1990s scientists knew of less than 200 of such outer space rocks, but with better telescopes and more efforts at surveying, the numbers of known asteroids has grown dramatically.

But, there are only a trickle of papers that describe individual asteroids. Once a new asteroid is discovered, modeling it takes several months, if not longer, said Engels. The research is painstaking.

In the mid‑1990s, Hudson, who has an asteroid named after him, wrote the primary modeling software tool that researchers use to describe asteroids and their behavior. Using ground-based radar and optics data, the software helps researchers learn important information, such as an asteroid’s possible mineral make-up, current and future orbit, shape, and how it spins in space. In fact, Hudson co-authored a paper published in Science that determined that at least one asteroid, 1950 DA, has a very tiny chance of hitting earth during a precise 20‑minute period in March of 2880.

“The software was written for a super computer, so it’s really, really slow,” said Engels, who jumped at improving it for his PhD project. “It can take a long time to do the modeling to draw any conclusions from it, and it takes awhile to crunch the data to write a paper in the first place.”

Asteroids made from clay next to asteroids made using a computer model.
To check the accuracy of their computer model, the researchers compared their results to clay models of asteroids. The bottom right image comes from the computer model, and the bottom left is an image of the model asteroid. (Credit: WSU)

The new version of code works much faster. The researchers revised it to make operations work concurrently instead of performing one at a time. Because the work is very similar to the everyday graphics that modern computers use to crunch out nice displays, the researchers transferred the operations to the computer’s graphics processing units, or GPUs. GPUs are designed to perform complex mathematical and geometric calculations for graphics rendering and have a tremendous amount of power to do parallel calculations.

“It’s taking advantage of the horsepower that is used in computer graphics rendering,” Engels said. “It’s very cost effective and you don’t need a super computer. You can use a consumer level graphics card available for under $500.”

The improvements to the algorithms could also someday be used for a variety of other purposes, said Engels, who works as a research engineer at Pacific Northwest National Laboratory, such as for modeling systems in the electric power grid or gas and oil industry.

Engels is verifying the code with real asteroid data. He hopes to have it available to the astronomy community later this year.

Journal Reference: Astronomy and Computing

Materials provided by Washington State University

Study demonstrates stress reduction benefits from petting dogs, cats

Study demonstrates stress reduction benefits from petting dogs, cats

College is stressful. Students have classes, papers, and exams. But they also often have work, bills to pay, and so many other pressures common in modern life.

Many universities have instituted “Pet your stress away” programs, where students can come in and interact with cats and/or dogs to help alleviate some of the strain.

Scientists at Washington State University have recently demonstrated that, in addition to improving students’ moods, these programs can actually get “under the skin” and have stress-relieving physiological benefits.

“Just 10 minutes can have a significant impact,” said Patricia Pendry, an associate professor in WSU’s Department of Human Development. “Students in our study that interacted with cats and dogs had a significant reduction in cortisol, a major stress hormone.”

Pendry published these findings with WSU graduate student Jaymie Vandagriff last month in AERA Open, an open access journal published by the American Educational Research Association.

This is the first study that has demonstrated reductions in students’ cortisol levels during a real-life intervention rather than in a laboratory setting.

The study involved 249 college students randomly divided into four groups. The first group received hands-on interaction in small groups with cats and dogs for 10 minutes. They could pet, play with, and generally hang out with the animals as they wanted.

To compare effects of different exposures to animals, the second group observed other people petting animals while they waited in line for their turn. The third group watched a slideshow of the same animals available during the intervention, while the fourth group was “waitlisted”. Those students waited for their turn quietly for 10 minutes without their phones, reading materials, or other stimuli, but were told they would experience animal interaction soon.

Several salivary cortisol samples were collected from each participant, starting in the morning when they woke up. Once all the data was crunched from the various samples, the students who interacted directly with the pets showed significantly less cortisol in their saliva after the interaction. These results were found even while considering that some students may have had very high or low levels to begin with.

“We already knew that students enjoy interacting with animals, and that it helps them experience more positive emotions,” Pendry said. “What we wanted to learn was whether this exposure would help students reduce their stress in a less subjective way. And it did, which is exciting because the reduction of stress hormones may, over time, have significant benefits for physical and mental health.”

Now Pendry and her team are continuing this work by examining the impact of a four-week-long animal-assisted stress prevention program. Preliminary results are very positive, with a follow-up study showing that the findings of the recently published work hold up. They hope to publish the final results of that work in the near future.

Journal: https://journals.sagepub.com/doi/10.1177/2332858419852592

Materials provided by Washington State University

iceworm

Unlocking secrets of the ice worm

The ice worm is one of the largest organisms that spends its entire life in ice and Washington State University scientist Scott Hotaling is one of the only people on the planet studying it.

He is the author of a new paper that shows ice worms in the interior of British Columbia have evolved into what may be a genetically distinct species from Alaskan ice worms.

Hotaling and colleagues also identified an ice worm on Vancouver Island that is closely related to a separate population of ice worms located 1,200 miles away in southern Alaska. The researchers believe the genetic intermingling is the result of birds eating the glacier-bound worms (or their eggs) at one location and then dropping them off at another as they migrate up and down the west coast.

“If you are a worm isolated on a mountaintop glacier, the expectation is you aren’t going anywhere,” said Hotaling, a postdoctoral biology researcher. “But lo and behold, we found this one ice worm on Vancouver Island that is super closely related to ice worms in southern Alaska. The only reasonable explanation we can think of to explain this is birds.”

Super cool organism

The ice worm resembles the common earthworm but is smaller and darker in color.  What sets the ice worm apart from other members of the Mesenchytraeus genus is its ability to live its entire life in glacial ice.

Millions, perhaps hundreds of millions, of ice worms can be seen wriggling to the top of glaciers from the Chugach Mountains in southeast Alaska to the Cascade Volcanoes of Washington and Oregon during the summer months. In the fall and winter, ice worms subsist deep beneath the surface of glaciers where temperatures stay around freezing.

Scott Hotaling

Hotaling’s interest in ice worms began back in 2009 while he was working as a mountaineering ranger on the high elevation slopes of Mt. Rainer. He was climbing at three in the morning when he noticed a lot of small, black worms crawling around on the surface of a glacier.

“I wasn’t even a biology undergraduate yet but I remember being so fascinated by the fact that there is this worm that can live in a glacier,” he said. “It is not a place where we think of life being able to flourish and these things can be present at like 200 per sq. meter, so dense you can’t walk without stepping in them.”

Hotaling eventually went back to school and earned a PhD in biology at the University of Kentucky where he studied how climate change is affecting mountain biodiversity.

In the summer of 2017, he finally got the opportunity to circle back and do some research on the ice worm when he arrived in Pullman to start a postdoc position in the laboratory of Associate Professor Joanna Kelley, senior author of the study who specializes in evolutionary genomics and extremophile lifeforms.

“In the Kelley lab, we study organisms that have evolved to live in places that are inhospitable to pretty much everything else,” Hotaling said. “Determining the evolutionary mechanisms that enable something like an ice worm to live in a glacier or bacteria to live in a Yellowstone hot spring is a really exciting way to learn about what is possible at the bounds of evolution. That’s where we are working now, understanding the evolution of ice worms.”

In the study

Hotaling and colleagues extracted and sequenced DNA from 59 ice worms collected from nine glaciers across most of their geographical range. Their analysis revealed a genetic divergence between populations of ice worms that are north and west and south and east of the Coast Mountains of British Columbia.

The researchers predict that this deeper split into two genetically distinct ice worm groups occurred as a result of glacial ice sheets contracting around a few hundred thousand years ago, isolating worms in the Pacific Northwest from their counterparts in Alaska.

The most surprising finding of the study was the discovery of a single ice worm on Vancouver Island that was closely related to a population of ice worms 1,200 miles away in Alaska.

“At first we thought there has to be some kind of error in the analysis or prep methods but upon further investigation we confirmed our initial results,” Hotaling said. “These are worms isolated on mountain tops and there is no explanation for how they covered that gap than on, or perhaps within, migrating birds.”

A Gray-Crowned Rosy Finch eating ice worms.
A Gray-Crowned Rosy Finch eating ice worms on a glacier. Photo by Scott Hotaling

The research illuminates an important relationship between two of the few large organisms that inhabit North America’s high elevation alpine ecosystems, the ice worm and the Gray-Crowned Rosy Finch, one of North America’s highest elevation nesting birds.

“We knew that ice worms were an important source of food for the birds but we didn’t know until now that the birds are also likely very important for the ice worms,” Hotaling said. “If you are super isolated like an ice worm, you could easily become inbred. But if birds are bringing little bits of new diversity to your mountaintop glacier that could be really good for you.”

Hotaling and Kelley’s study was published this month in Proceedings B of the Royal Society of Publishing.

Materials provided by Washington State University

Turmeric can prevent cancer

Timed release of turmeric stops cancer cell growth

A Washington State University research team has developed a drug delivery system using curcumin, the main ingredient in the spice turmeric, that successfully inhibits bone cancer cells while promoting the growth of healthy bone cells.

The work could lead to better post‑operative treatments for people with osteosarcoma, the second most prevalent cause of cancer death in children.

The researchers, including Susmita Bose, Herman and Brita Lindholm Endowed Chair Professor in the School of Mechanical and Materials Engineering, and graduate student Naboneeta Sarkar, report on their work in the journal, ACS Applied Materials and Interfaces.

Young patients with bone cancer are often treated with high doses of chemotherapy before and after surgery, many of which have harmful side effects. Researchers would like to develop gentler treatment options, especially after surgery when patients are trying to recover from bone damage at the same time that they are taking harsh drugs to suppress tumor growth.

Turmeric has been used in cooking and as medicine for centuries in Asian countries, and its active ingredient, curcumin has been shown to have anti‑oxidant, anti‑inflammatory and bone‑building capabilities. It has also been shown to prevent various forms of cancers.

“I want people to know the beneficial effects of these natural compounds,” said Bose. “Natural biomolecules derived from these plant‑based products are inexpensive and a safer alternative to synthetic drugs.”

However, when taken orally as medicine, the compound can’t be absorbed well in the body. It is metabolized and eliminated too quickly.

Closeup of Bose in laboratory.
Susmita Bose

In their study, the researchers used 3D printing to build support scaffolds out of calcium phosphate. While most implants are currently made of metal, such ceramic scaffolds, which are more like real bone, could someday be used as a graft material after bone cancer surgery. The researchers incorporated curcumin, encapsulated in a vesicle of fat molecules into the scaffolds, allowing for the gradual release of the chemical.

The researchers found that their system inhibited the growth of osteosarcoma cells by 96 percent after 11 days as compared to untreated samples. The system also promoted healthy bone cell growth.

“This study introduces a new era of integration – where modern 3D printing technology is coupled with the safe and effective use of alternative medicine, which may provide a better tool for bone tissue engineering,” said Bose.

The researchers are continuing the unique area of research, studying the benefits of integrating other natural compounds in biomedical technology. The work was funded by the National Institutes of Health.

Materials provided by Washington State University