Simon Fraser University

Putting bedbugs to bed forever

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A team of scientists has found a way to conquer the global bedbug epidemic. By lending their own arms for thousands of bed bug bites, they have finally found the solution — a set of chemical attractants, or pheromones, that lure the bedbugs into traps, and keep them there.

By giving blood weekly to her life partner’s bug experiment, SFU scientist Regine Gries has all but given us the gift of freedom from bed bug torture.

The world owes a debt of gratitude to Simon Fraser University biologist Regine Gries. Her arms have provided a blood meal for more than a thousand bedbugs each week for five years while she and her husband, biology professor Gerhard Gries, searched for a way to conquer the global bedbug epidemic.

Working with SFU chemist Robert Britton and a team of students, they have finally found the solution–a set of chemical attractants, or pheromones, that lure the bedbugs into traps, and keep them there.

This month, after a series of successful trials in bedbug-infested apartments in Metro Vancouver, they have published their research, “Bedbug aggregation pheromone finally identified,” in Angewandte Chemie, a general chemistry journal.

They’re working with Victoria-based Contech Enterprises Inc. to develop the first effective and affordable bait and trap for detecting and monitoring bedbug infestations. They expect it to be commercially available next year.

“The biggest challenge in dealing with bedbugs is to detect the infestation at an early stage,” says Gerhard, who holds an NSERC-Industrial Research Chair in Multimodal Animal Communication Ecology.

“This trap will help landlords, tenants, and pest-control professionals determine whether premises have a bedbug problem, so that they can treat it quickly. It will also be useful for monitoring the treatment’s effectiveness.”

It’s a solution the world has been waiting for.

Over the last two decades the common bedbug (Cimex lectularius), once thought eradicated in industrialized countries, has reappeared as a global scourge. These nasty insects are infesting not just low-income housing but also expensive hotels and apartments, and public venues such as stores, movie theatres, libraries and even public transit.

And while these blood-sucking pests were previously not considered a carrier of disease, scientists have recently discovered they can transmit the pathogen that causes Chagas disease, which is prevalent in Central and South America. Yet until now, tools for detecting and monitoring these pests have been expensive and technically challenging to use.

The research was funded with a Natural Sciences and Engineering Research Council of Canada industry grant in partnership with Contech Enterprises Inc.

Backgrounder: The research story–180,000 bedbug bites later

The Gries’ began their research eight years ago when Gerhard, who is internationally renowned for his pioneering work in chemical and bioacoustic communication between insects, began searching for pheromones that could lure and trap bedbugs.

Regine worked with him, running all of the lab and field experiments and, just as importantly, enduring 180,000 bedbug bites in order to feed the large bedbug colony required for their research. She became the unintentional “host” because, unlike Gerhard, she is immune to the bites, suffering only a slight rash instead of the ferocious itching and swelling most people suffer.

The Gries’ and their students initially found a pheromone blend that attracted bedbugs in lab experiments, but not in bedbug-infested apartments. “We realized that a highly unusual component must be missing–one that we couldn’t find using our regular gas chromatographic and mass spectrometric tools,” says Gerhard.

That’s when they teamed up with Britton, an expert in isolating and solving the structure of natural products, and then synthesizing them in the lab. He used SFU’s state-of-the-art NMR spectrometers to study the infinitesimal amounts of chemicals Regine had isolated from shed bedbug skin, looking for the chemical clues as to why the bedbugs find the presence of skin so appealing in a shelter.

It was like looking for a needle in a haystack.

After two years of frustrating false leads, Britton, his students and the Gries duo finally discovered that histamine, a molecule with unusual properties that eluded identification through traditional methods, signals “safe shelter” to bedbugs. Importantly, once in contact with the histamine, the bedbugs stay put whether or not they have recently fed on a human host.

Yet, to everyone’s disbelief, neither histamine alone nor in combination with the previously identified pheromone components effectively attracted and trapped bedbugs in infested apartments. So Regine began analyzing airborne volatile compounds from bedbug faeces as an alternate source of the missing components.

Five months and 35 experiments later, she had found three new volatiles that had never before been reported for bedbugs. These three components, together with two components from their earlier research and, of course, histamine, became the highly effective lure they were seeking.

Their research isn’t over yet, however. They continue to work with Contech Enterprises to finalize development of the commercial lure–which means Regine is still feeding the bedbugs every week. “I’m not too thrilled about this,” admits Regine, “but knowing how much this technology will benefit so many people, it’s all worth it.”

Story Source:

The above story is based on materials provided by Simon Fraser University. Note: Materials may be edited for content and length.

Journal Reference:

  1. Regine Gries, Robert Britton, Michael Holmes, Huimin Zhai, Jason Draper, Gerhard Gries. Bed Bug Aggregation Pheromone Finally Identified. Angewandte Chemie International Edition, 2014; DOI: 10.1002/anie.201409890

ADHD: Scientists discover brain’s anti-distraction system.

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Two Simon Fraser University psychologists have made a brain-related discovery that could revolutionize doctors’ perception and treatment of attention-deficit disorders.

Psychologists have made a brain-related discovery that could revolutionize doctors’ perception and treatment of attention-deficit disorders. This discovery opens up the possibility that environmental and/or genetic factors may hinder or suppress a specific brain activity that the researchers have identified as helping us prevent distraction.

 


This discovery opens up the possibility that environmental and/or genetic factors may hinder or suppress a specific brain activity that the researchers have identified as helping us prevent distraction.
The Journal of Neuroscience has just published a paper about the discovery by John McDonald, an associate professor of psychology and his doctoral student John Gaspar, who made the discovery during his master’s thesis research.
This is the first study to reveal our brains rely on an active suppression mechanism to avoid being distracted by salient irrelevant information when we want to focus on a particular item or task.
McDonald, a Canada Research Chair in Cognitive Neuroscience, and other scientists first discovered the existence of the specific neural index of suppression in his lab in 2009. But, until now, little was known about how it helps us ignore visual distractions.
“This is an important discovery for neuroscientists and psychologists because most contemporary ideas of attention highlight brain processes that are involved in picking out relevant objects from the visual field. It’s like finding Waldo in a Where’s Waldo illustration,” says Gaspar, the study’s lead author.
“Our results show clearly that this is only one part of the equation and that active suppression of the irrelevant objects is another important part.”
Given the proliferation of distracting consumer devices in our technology-driven, fast-paced society, the psychologists say their discovery could help scientists and health care professionals better treat individuals with distraction-related attentional deficits.
“Distraction is a leading cause of injury and death in driving and other high-stakes environments,” notes McDonald, the study’s senior author. “There are individual differences in the ability to deal with distraction. New electronic products are designed to grab attention. Suppressing such signals takes effort, and sometimes people can’t seem to do it.
“Moreover, disorders associated with attention deficits, such as ADHD and schizophrenia, may turn out to be due to difficulties in suppressing irrelevant objects rather than difficulty selecting relevant ones.”
The researchers are now turning their attention to understanding how we deal with distraction. They’re looking at when and why we can’t suppress potentially distracting objects, whether some of us are better at doing so and why that is the case.
“There’s evidence that attentional abilities decline with age and that women are better than men at certain visual attentional tasks,” says Gaspar, the study’s first author.
The study was based on three experiments in which 47 students performed an attention-demanding visual search task. Their mean age was 21. The researchers studied their neural processes related to attention, distraction and suppression by recording electrical brain signals from sensors embedded in a cap they wore.
Story Source:
The above story is based on materials provided by Simon Fraser University. Note: Materials may be edited for content and length.
Journal Reference:
J. M. Gaspar, J. J. McDonald. Suppression of Salient Objects Prevents Distraction in Visual Search. Journal of Neuroscience, 2014; 34 (16): 5658 DOI: 10.1523/JNEUROSCI.4161-13.2014

Quantum ‘world record’ smashed

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An artistic rendition of a 'bound exciton' quantum state used to prepare and read out the state of the qubits
Quantum systems are notoriously fickle to measure and manipulate

A fragile quantum memory state has been held stable at room temperature for a “world record” 39 minutes – overcoming a key barrier to ultrafast computers.

“Qubits” of information encoded in a silicon system persisted for almost 100 times longer than ever before.

Quantum systems are notoriously fickle to measure and manipulate, but if harnessed could transform computing.

The new benchmark was set by an international team led by Mike Thewalt of Simon Fraser University, Canada.

“Start Quote

“39 minutes may not seem very long. But these lifetimes are many times longer than previous experiments”

Stephanie Simmons Oxford University

“This opens the possibility of truly long-term storage of quantum information at room temperature,” said Prof Thewalt, whose achievement is detailed in the journal Science.

In conventional computers, “bits” of data are stored as a string of 1s and 0s.

But in a quantum system, “qubits” are stored in a so-called “superposition state” in which they can be both 1s and 0 at the same time – enabling them to perform multiple calculations simultaneously.

The trouble with qubits is their instability – typical devices “forget” their memories in less than a second.

There is no Guinness Book of quantum records. But unofficially, the previous best for a solid state system was 25 seconds at room temperature, or three minutes under cryogenic conditions.

In this new experiment, scientists encoded information into the nuclei of phosphorus atoms held in a sliver of purified silicon.

Magnetic field pulses were used to tilt the spin of the nuclei and create superposition states – the qubits of memory.

The team prepared the sample at -269C, close to absolute zero – the lowest temperature possible.

Artist's impression of a phosphorus atom qubit in silicon, showing a ticking clock

When they raised the system to room temperature (just above 25C) the superposition states survived for 39 minutes.

What’s more, they found they could manipulate the qubits as the temperature of the system rose and fell back towards absolute zero.

At cryogenic temperatures, their quantum memory system remained coherent for three hours.

“Having such robust, as well as long-lived, qubits could prove very helpful for anyone trying to build a quantum computer,” said co-author Stephanie Simmons of Oxford University’s department of materials.

“39 minutes may not seem very long. But these lifetimes are many times longer than previous experiments.

“We’ve managed to identify a system that seems to have basically no noise.”

However she cautions there are still many hurdles to overcome before large-scale quantum computations can be performed.

For one thing, their memory device was built with a highly purified form of silicon – free from the magnetic isotopes which interfere with the spin of nuclei.

For another, the spins of the 10 billion or so phosphorus ions used in this experiment were all placed in the same quantum state.

Continue reading the main story

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“What’s most important is this is silicon. The global investment in this material means it has a lot of potential for engineering”

Dr Thaddeus Ladd HRL Laboratories

Whereas to run calculations, physicists will need to place different qubits in different states – and control how they couple and interact.

“To have them controllably talking to one another – that would address the last big remaining challenge,” said Dr Simmons.

Independent experts in the quantum field said the new record was an “exciting breakthrough” that had long been predicted.

“This result represents an important step towards realising quantum devices,” said David Awschalom, professor in Spintronics and Quantum Information, at the University of Chicago.

“However, a number of intriguing challenges still remain. For instance – will it be possible to precisely control the local electron-nuclear interaction to enable initialisation, storage, and readout of the nuclear spin states?”

The previous “world record” for a solid state quantum system at room temperature – 25 seconds – was held by Dr Thaddeus Ladd, formerly of Stanford University‘s Quantum Information Science unit, now working for HRL Laboratories.

“It’s remarkable that these coherence states could be held for so long in a measurable system – as measurement normally introduces noise,” he told BBC News.

“It’s also a nice surprise that nothing goes wrong warming up and cooling the sample again – from an experimental point of view that’s pretty remarkable.

“What is perhaps most important is that this is silicon. The global investment in this particular material means that it has a lot of potential for engineering.”

Pesticides are Killing More Than Bees – They’re Killing Humans.

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bees-flowersThat’s just one example of how the ecological balance can be interrupted. Why is this happening? Several factors have been identified, including:

One poignant example of the pesticide problem comes with a lawsuit filed by The German Coalition against Bayer Dangers against Werner Wenning, chairman of the Bayer Board of Management, after losing thousands of hives due to poisoning by the pesticide clothianidin. Bayer was accused of marketing dangerous pesticides that allegedly caused the mass death of bees all over the world. In fact, apple orchards require at least one bee colony for every acre to be adequately pollinated. So, unless this devastating trend is reversed, the world could be in for some major food shortages.

Even more alarming may be the rate at which wild bees are dropping from sight, particularly regarding crop yields, according to a worldwide study.6 Coffee, onions, almonds, tomatoes and strawberries were among 40 fruits and vegetables in 600 fields examined by scientists to determine which would win the pollination race. The report returned that wild bees were twice as effective as honey bees in this endeavor.7

Scientists studied the pollination of more than 40 crops in 600 fields across every populated continent and found wild pollinators were twice as effective as honey bees in producing seeds and fruit on crops including oilseed rape, coffee, onions, almonds, tomatoes and strawberries. Furthermore, trucking in managed honey bee hives did not replace wild pollination when that was lost, but only added to the pollination that took place.8

One of every three bites of food you eat depends on the honey bee. They pollinate at least 130 different crops in the US alone, including fruits, vegetables and tree nuts. That bees can actually sense and respond to electrical fields emitted by flowering plants is remarkable, says bee biologist and author Mark Winston from Simon Fraser University in Burnaby, B.C. He adds:

“[B]ees perceive the world around them, and it adds another wonderful story that continues to deepen our understanding the co-evolved relationship between bees and flowers.”

Only a change in the status quo will cause a turnaround of this tragic situation that threatens not only bees all over the world, but the world’s entire, increasingly unsustainable food system.

Source: mercola.com