quarta-feira, 24 de dezembro de 2014

Putting bedbugs to bed forever

 

 

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

The curious beginnings of 5 common surgical tools –/republ.-/

 

 

Think surgery is painful now? Imagine it before anesthesia.

UNDER THE KNIFE: Medical procedures have advanced tremendously over the years. (Photo: Official U.S. Navy Imagery/Flickr)

Surgical stapling and anesthesia are common sights in a modern operating room, but it wasn't always that way. Some of these tools and processes have interesting and downright weird origins — long before they could be found in every operating room in the world.

Nitrous oxide

Dental surgeries before the 1840s were particularly painful because even the most basic forms of anesthesia had yet to be discovered. Thankfully, a traveling sideshow would provide the inspiration for this badly needed necessity.

Horace Wells first spotted the possibility for nerve-numbing gases in 1844 at a traveling circus show where he witnessed members of the audience turn into giggling morons, simply by inhaling large doses of nitrous oxide also known as "laughing gas." Wells tested his discovery on one volunteer patient by extracting a tooth after putting him under with the gas and found that the volunteer did not feel any pain during the extraction. He later had the gas tested on himself with similar success and proclaimed it as a "new era in tooth pulling."

Absorbable sutures

The pioneering Muslim surgeon al-Zahrawi invented many of the most basic tools used by surgeons. His dissolving sutures, however, provide easily the most interesting discovery story.

The 10th-century surgeon reportedly discovered that catgut strings served as the perfect internal sutures to repair wounds during surgical procedures. He came across this discovery after his pet monkey accidentally swallowed some of the strings from his lute. He found that they dissolved naturally in the body without any side effects or internal injuries. His discovery also served as the perfect material for making medicinal capsules.

General anesthesia

Henry Hill Hickman, one of the earliest experimenters in anesthesia, blazed an interesting path in the field with his strange experiments, one of which lead to less lethal consequences.

Hickman discovered the numbing properties of carbon dioxide by anesthetizing animals and removing their limbs to see how they reacted to the pain. Of course, he failed to realize that carbon dioxide could have deadly consequences if carbon based life forms inhale too much of it. His findings were widely criticized and his subsequent scientific endeavors weren't pursued, but he posthumously earned recognition as one of the founding fathers of anesthesia.

Surgical stapling

Surgical staplers have been a part of the surgical technologist's toolbox since as far back as the early 1900s, but the earliest devices were as cumbersome and complicated as the operation itself.

The first known prototype of the surgical stapler was invented by Humer Hulti, a Hungarian surgeon who is known as "the father of surgical stapling." His invention weighed a hefty eight pounds and required two hours of preparation. It also took several hours to fully staple a wound shut since it required an iron set of hands to keep the cumbersome device steady enough to make a straight staple line.

Skin glue

Stitching and suturing — the long time standard for closing wounds — were recently replaced by skin glue. However, long before stitching became the standard, the more recent innovation in surgical technology got its start.

Dr. Harry Coover, a scientist for Kodak Laboratories in the 1940s, was trying to concoct a solution for clear plastic to afix gun sights to the barrels of rifles. One solution, called "cyanoacrylates," came close to achieving this goal, but was tossed aside as unfit for production. Six years later, he revisited his formula to create plastic that could be made into airplane canopies and found that it made a very strong adhesive. Later in the 1960s, he submitted an application to the Food and Drug Administration (FDA) to use his "super glue" on injured soldiers to seal wounds in the field. His solution was battle-tested on wounded soldiers during the Vietnam War with great success. However, Coover (pictured right) didn't obtain approval for use on civilians until 1998 when the FDA approved it for use in stateside hospitals and surgical procedures.

Trans fat: Avoid this cholesterol double whammy

 

 

Trans fat is double trouble for your heart health

Trans fat raises your LDL ("bad") cholesterol and lowers your HDL ("good") (HDL) cholesterol. Find out more about trans fat and how to avoid it.

Trans fat is considered by many doctors to be the worst type of fat you can eat. Unlike other dietary fats, trans fat — also called trans-fatty acids — both raises your LDL ("bad") cholesterol and lowers your HDL ("good") cholesterol.

A high LDL cholesterol level in combination with a low HDL cholesterol level increases your risk of heart disease, the leading killer of men and women. Here's some information about trans fat and how to avoid it.

What is trans fat?

Some meat and dairy products contain small amounts of naturally occurring trans fat. But most trans fat is formed through an industrial process that adds hydrogen to vegetable oil, which causes the oil to become solid at room temperature.

This partially hydrogenated oil is less likely to spoil, so foods made with it have a longer shelf life. Some restaurants use partially hydrogenated vegetable oil in their deep fryers, because it doesn't have to be changed as often as do other oils.

Trans fat in your food

The manufactured form of trans fat, known as partially hydrogenated oil, is found in a variety of food products, including:

  • Baked goods. Most cakes, cookies, pie crusts and crackers contain shortening, which is usually made from partially hydrogenated vegetable oil. Ready-made frosting is another source of trans fat.
  • Snacks. Potato, corn and tortilla chips often contain trans fat. And while popcorn can be a healthy snack, many types of packaged or microwave popcorn use trans fat to help cook or flavor the popcorn.
  • Fried food. Foods that require deep frying — french fries, doughnuts and fried chicken — can contain trans fat from the oil used in the cooking process.
  • Refrigerator dough. Products such as canned biscuits and cinnamon rolls often contain trans fat, as do frozen pizza crusts.
  • Creamer and margarine. Nondairy coffee creamer and stick margarines also may contain partially hydrogenated vegetable oils.
Reading food labels

In the United States if a food has less than 0.5 grams of trans fat in a serving, the food label can read 0 grams trans fat. This hidden trans fat can add up quickly, especially if you eat several servings of multiple foods containing less than 0.5 grams a serving.

When you check the food label for trans fat, also check the food's ingredient list for partially hydrogenated vegetable oil — which indicates that the food contains some trans fat, even if the amount is below 0.5 grams.

  • Trans fat, particularly the manufactured variety found in partially hydrogenated vegetable oil, appears to have no known health benefit. The Department of Agriculture recommends that the intake of trans fat be kept as low as possible.

The Food and Drug Administration (FDA) has made a preliminary determination that partially hydrogenated vegetable oil is no longer "generally recognized as safe" and should eventually be phased out of the production of food. However, the FDA's preliminary determination must go through a lengthy review process before it becomes finalized.

How trans fat harms you

Doctors worry about trans fat because of its unhealthy effect on your cholesterol levels — increasing your LDL and decreasing your HDL cholesterol. There are two main types of cholesterol:

  • Low-density lipoprotein (LDL). LDL, or "bad," cholesterol can build up in the walls of your arteries, making them hard and narrow.
  • High-density lipoprotein (HDL). HDL, or "good," cholesterol picks up excess cholesterol and takes it back to your liver.

If the fatty deposits within your arteries tear or rupture, a blood clot may form and block blood flow to a part of your heart, causing a heart attack, or to a part of your brain, causing a stroke.

What should you eat?

Don't think a food that is free of trans fat is automatically good for you. Food manufacturers have begun substituting other ingredients for trans fat. Some of these ingredients, such as tropical oils — coconut, palm kernel and palm oils — contain a lot of saturated fat. Saturated fat raises your LDL cholesterol.

In a healthy diet, 25 to 35 percent of your total daily calories can come from fat — but saturated fat should account for less than 10 percent of your total daily calories.

Monounsaturated fat — found in olive, peanut and canola oils — is a healthier option than is saturated fat. Nuts, fish and other foods containing unsaturated omega-3 fatty acids are other good choices of foods with monounsaturated fats.

7 Sleep Mistakes You Don’t Know You’re Making and How to Fix Them

 

A shocking number of us have trouble sleeping on a regular basis, but there are some very simple reasons why that might be. This infographic from The Sleep Matters Club highlights some common sleep mistakes that many of us make and explains how we can fix them.

 

7 Sleep Mistakes You Don’t Know You’re Making and How to Fix Them

Filed in: Lifestyle Infographics

About the Author (Author Profile)
David Wallace is a search & social media marketer who lives in Anthem Arizona with his lovely wife. Interests & hobbies include all things Disney, roller coasters, musicianship and Christianity. Follow +David Wallace on Google + as well as Twitter.

Taoshouse home's energy needs expected to be met by solar array

 

 

The Taoshouse in New Mexico, US, is expected to run entirely on electricity generated by i...

The Taoshouse in New Mexico, US, is expected to run entirely on electricity generated by its solar power system

Image Gallery (7 images)

A home built in New Mexico, US, is expected to run entirely from the electricity generated from energy harvested by its nine 230 W solar panels. The Taoshouse also has a number of design features to help keep power usage to a minimum.

Like the Active House prototype in Missouri, US, the Taoshouse is designed to look and feel like a normal home and not some futuristic box. Located in a senior co-housing community in the town of Taos, the Taoshouse has a clean interior aesthetic with plaster walls and floor-to-ceiling bamboo casement work. Both projects show the potential for net-zero energy housing.

Project designer Needbased says that part of the brief for the Taoshouse design was to ensure that it would achieve Passive House Certification and meet the highest level of the National Association of House Builders (NAHB) green building standard. According to Needbased, the house has achieved both of these goals and, as such, is one of only a handful of North American buildings to be certified by the Passive House Institute in Germany.

The Taoshouse kitchen

The Taoshouse has an internal area of 1,632 sq ft (152 sq m) and covers a total area of 2,870 sq ft (267 sq m). It can pull electricity from the grid if needs be, or feed any surplus back into the grid. To date, the home has had an energy usage of 1.87 kWh / sq ft (20.13 kWh / sq m).

"Over the past ten months since the project was completed, the house has used 3,100 kWh and generated 2,800 kWh," Jonah Stanford of Needbased tells Gizmag. "The first year of energy use is expected to be higher than the norm due to the latent energy of the moisture of all the building materials used. I expect the overall energy use to come down slightly after the building has fully dried out."

The house is kept cool using passive shading and night-sky cooling. In order to minimize heat loss, it is highly insulated in the walls, under slab and roof and employs high performance Zola windows.

An energy recovery ventilator is used to condition incoming air with air that is being exhausted from the building. This means incoming air can be warmed and dehumidified, for example. An underfloor hydronic radiant system, meanwhile, is used to heat the building.

The Taoshouse was completed earlier this year.

Source: Needbased

 

Mechanic Advisor's Connection Key tells you what’s wrong with your car, and who can fix it

 

 

Mechanic Advisor's Connection Key is deisgned to make auto maintenance and repairs less st...

Mechanic Advisor's Connection Key is deisgned to make auto maintenance and repairs less stressful

Image Gallery (4 images)

Mechanic Advisors’ new product is designed to make the appearance of the dreaded check engine light that little bit less disheartening, by giving car owners a portal into the health of their vehicle. The device provides drivers with the same information available to their local auto repair shop, but what makes it truly unique is its ability to put them in touch with a suitable, trustworthy mechanic.

The device plugs into the vehicle's standard On-Board Diagnostics (OBD) port, linking to iOS and Android smartphones to provide real-time vehicle data and decipher more than 20,000 error codes – the exact same diagnostic tools available to mechanics. It’ll also provide alerts when it’s time to change oil or replace tires, and according to the company, will work with almost any vehicle manufactured form 1996 onwards.

If and when a problem arises, the companion app will link you directly to one of more than half a million trusted mechanics, making it easier to get your vehicle into a reliable repair shop. In future, the company plans to improve the service by using anonymous data to provide useful information such as known issues for specific models of car, breaking down stats based on location and driving habits.

The device plugs into the standard On-Board Diagnostics (OBD) port, linking to iOS and And...

The company believes that giving drivers real-time stats will not only help educate them about their vehicles, but should also eliminate the distrust surrounding auto repairs. When your check engine light flicks on, you simply fire up the app to see what’s wrong and contact a mechanic suitable for fixing the specific issue, as selected by the company’s online referral engine. It’s a two-way street – the driver can easily see what’s wrong with their vehicle, and the mechanics can make their recommendations backed up to said data.

The Connection Key is also built with safety in mind, with all data being encrypted when transferred between the device and the user’s smartphone. The same goes for the web servers used to track down a suitable mechanic.

If you’re interested in picking up a Connection Key, then you’ll be pleased to learn that it’s available for pre-order right now for US$50 including shipping. The price is set to rise to $75 when it becomes widely available in Q1 2015. Potential buyers might also want to check out the Automatic Link, an existing device that offers some of the same features.

Source: Mechanic Advisor

 

Latest S House prototype can be assembled in just 3 hours

 

 

The S House 3, by Vo Trong Nghia Architects (Photo: Hiroyuki Oki)

The S House 3, by Vo Trong Nghia Architects (Photo: Hiroyuki Oki)

Image Gallery (11 images)

Back in September, we reported on Vo Trong Nghia Architects' ongoing effort to produce a suitable home for Vietnam's poor. The latest iteration of the firm's low-cost S House sees the prototype home refined, and the prefabricated dwelling now sports a more stable structure, and an impressive on-site build time of just three hours.

Completed in November and installed in Ho Chi Minh City, the S House 3 has just one large interior space inside that measures 31.6 sq m (340 sq ft). Whereas the previous S House was built from a pre-cast concrete frame bolted together with steel fixings, this newest version comprises a lightweight steel framework, cement board cladding, and a reinforced concrete foundation.

"The aim of this serial project is to provide stable but lightweight, permanent but affordable homes for low-income earners in a harsh tropical climate," says Vo Trong Nghia Architects. "Although there are many local challenges such as weak ground condition, frequent typhoon and potential earthquake, the structure is stable enough to withstand natural disasters."

Vo Trong Nghia aims to eventually start selling the home all around Vietnam, South East As...

As was the case with its predecessor, the S House 3 features a small gap between its roof and walls, and several operable windows to encourage ventilation. Though it weighs 1,200 kg (2,645 lb), individual components are designed to be no more than 60 kg (132 lb), in order to allow easier transportation via shipping container or small boat.

Once on-site, it should take builders only around three hours to assemble the S House, and Vo Trong Nghia Architects reports that occupants will be able to maintain and repair it with relative ease.

We're awaiting confirmation from Vo Trong Nghia Architects on the expected cost of this model, though as the stated goal of the S House project is to produce an affordable home for poor Vietnamese, and the previous S House iteration cost just US$4,000, it should be relatively affordable. On that note, the firm hopes to eventually start selling the homes all over Vietnam, South East Asia, and elsewhere, including India and African countries.

Some work still remains for the project though, and there will be at least one further version of the S House before it hits the market.

Source: Vo Trong Nghia Architects

 

That smartphone is giving your thumbs superpowers

 

  While neuroscientists have long studied brain plasticity in expert groups--musicians or video gamers, for instance--smartphones present an opportunity to understand how regular life shapes the brains of regular people.

When people spend time interacting with their smartphones via touchscreen, it actually changes the way their thumbs and brains work together, according to a report in the Cell Press journal Current Biology on December 23. More touchscreen use in the recent past translates directly into greater brain activity when the thumbs and other fingertips are touched, the study shows.

"I was really surprised by the scale of the changes introduced by the use of smartphones," says Arko Ghosh of the University of Zurich and ETH Zurich in Switzerland. "I was also struck by how much of the inter-individual variations in the fingertip-associated brain signals could be simply explained by evaluating the smartphone logs."

It all started when Ghosh and his colleagues realized that our newfound obsession with smartphones could be a grand opportunity to explore the everyday plasticity of the human brain. Not only are people suddenly using their fingertips, and especially their thumbs, in a new way, but many of us are also doing it an awful lot, day after day. Not only that, but our phones are also keeping track of our digital histories to provide a readymade source of data on those behaviors.

Ghosh explains it this way: "I think first we must appreciate how common personal digital devices are and how densely people use them. What this means for us neuroscientists is that the digital history we carry in our pockets has an enormous amount of information on how we use our fingertips (and more)."

While neuroscientists have long studied brain plasticity in expert groups--musicians or video gamers, for instance--smartphones present an opportunity to understand how regular life shapes the brains of regular people.

To link digital footprints to brain activity in the new study, Ghosh and his team used electroencephalography (EEG) to record the brain response to mechanical touch on the thumb, index, and middle fingertips of touchscreen phone users in comparison to people who still haven't given up their old-school mobile phones.

The researchers found that the electrical activity in the brains of smartphone users was enhanced when all three fingertips were touched. In fact, the amount of activity in the cortex of the brain associated with the thumb and index fingertips was directly proportional to the intensity of phone use, as quantified by built-in battery logs. The thumb tip was even sensitive to day-to-day fluctuations: the shorter the time elapsed from an episode of intense phone use, the researchers report, the larger was the cortical potential associated with it.

The results suggest to the researchers that repetitive movements over the smooth touchscreen surface reshape sensory processing from the hand, with daily updates in the brain's representation of the fingertips. And that leads to a pretty remarkable idea: "We propose that cortical sensory processing in the contemporary brain is continuously shaped by personal digital technology," Ghosh and his colleagues write.

What exactly this influence of digital technology means for us in other areas of our lives is a question for another day. The news might not be so good, Ghosh and colleagues say, noting evidence linking excessive phone use with motor dysfunctions and pain.


Story Source:

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


Journal Reference:

  1. Arko Ghosh et al. Use-Dependent Cortical Processing from Fingertips in Touchscreen Phone Users. Current Biology, December 2014 DOI: 10.1016/j.cub.2014.11.026

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Way to control internal clocks discovered

 

In research published in Nature Communications, Thomas Burris, Ph.D., chair of pharmacological and physiological science at Saint Louis University, reports intriguing findings about a small molecule that directs the activity of key "clock proteins," offering the potential to manage circadian rhythm and treat problems that are associated with its dysfunction, like sleep and anxiety disorders.

Circadian rhythm refers to biological processes that cycle every 24 hours. In mammals, the internal clock that maintains circadian rhythm is essential for normal physiological functions. The rhythms can, however, be disrupted, and dysregulation of circadian rhythm is associated with many disorders, including metabolic disease and neuropsychiatric disorders including bipolar disorder, anxiety, depression, schizophrenia and sleep disorders.

Burris and his colleagues examined compounds that target a protein called REV-ERB, which appears to play a key role in regulating mammals' internal clocks.

"It has been suggested that REV-ERB is a core component of our clock," said Burris. "Mice without it are arrhythmic. This study demonstrated that when we give mice a synthetic compound that turns REV-ERB on, it altered their circadian rhythm."

The team examined effects of the REV-ERB drug on patterns of sleep and wakefulness and found that the compound increases wakefulness, reduces REM and slow-wave sleep, and, notably, decreases anxiety.

This is an interesting finding because it is unusual. Frequently, drugs that increase arousal (wakefulness) also increase anxiety (ex. cocaine, amphetamines). And, vice versa: Drugs that decrease anxiety also decrease arousal (ex. benzodiazepines and ethanol). An exception to this common pattern is nicotine.

The REV-ERB drug, on the other hand, appears to target the clock in a way that is distinct from these common pathways.

Further, the REV-ERB drug appears to be associated with a suppression of reward-seeking behavior.

Drug addiction has a circadian component and mice with mutations in "clock genes" (genes that affect our internal clocks) have altered responsiveness to the reward associated with cocaine, morphine and alcohol. Burris speculates that REV-ERB targeted drug effect on the clock would modulate reward-seeking behavior, and so may be useful in treating addiction.


Story Source:

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


Journal Reference:

  1. Subhashis Banerjee, Yongjun Wang, Laura A. Solt, Kristine Griffett, Melissa Kazantzis, Ariadna Amador, Bahaa M. El-Gendy, Salvador Huitron-Resendiz, Amanda J. Roberts, Youseung Shin, Theodore M. Kamenecka, Thomas P. Burris. Pharmacological targeting of the mammalian clock regulates sleep architecture and emotional behaviour. Nature Communications, 2014; 5: 5759 DOI: 10.1038/ncomms6759