Day: 02/17/2015

New ozone-destroying gases on the rise

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Scientists report that chemicals that are not controlled by a United Nations treaty designed to protect the Ozone Layer are contributing to ozone depletion.

In the new study, published today in Nature Geoscience, the scientists also report the atmospheric abundance of one of these ‘very short-lived substances’ (VSLS) is growing rapidly.

Study lead author Dr Ryan Hossaini, from the School of Earth and Environment at the University of Leeds, said: “VSLS can have both natural and industrial sources. Industrial production of VSLS is not controlled by the United Nations Montreal Protocol because historically these chemicals have contributed little to .

“But we have identified now that one of these chemicals is increasing rapidly and, if this increase is allowed to continue, it could offset some of the benefits to the Ozone Layer provided by the Montreal Protocol.”

In the study, the researchers used a 3D computer model of the atmosphere to determine the impact of VSLS on and climate.

Measurements of VSLS in the atmosphere over the past two decades, provided by collaborators from the National Oceanic and Atmospheric Administration (NOAA) in the United States, were also analysed. These measurements revealed a rapid increase in of dichloromethane, a man-made VSLS used in a range of industrial processes.

Study co-author Professor Martyn Chipperfield, from Leeds’ School of Earth and Environment, said: “We need to continue monitoring the atmospheric abundance of these gases and determine their sources. At present, the long-term recovery of the Ozone Layer from the effects of CFCs is still on track, but the presence of increasing dichloromethane will lead to uncertainty in our future predictions of ozone and climate.”

The researchers found that while the amount of ozone depletion arising from VSLS in the atmosphere today is small compared to that caused by longer-lived gases, such as CFCs, VSLS-driven ozone depletion was found to be almost four times more efficient at influencing climate.

Dr Hossaini explained: “Due to their short atmospheric lifetimes, VSLS break down and destroy ozone in the lowermost part of the stratosphere. This is important, as a molecule of ozone lost in this region has a far larger impact on climate than a molecule destroyed at higher altitudes by longer-lived gases.”

The researchers also separated out natural sources of VSLS – such as seaweed in the ocean – and those released due to human activity – such as – in order to determine the relative importance of each.

At present, naturally-emitted VSLS account for around 90% of the total ozone loss caused by VSLS in the lower stratosphere. However, the contribution from man-made VSLS compounds is increasing and appears set to increase further in coming years.

Study co-author Dr Stephen Montzka from the NOAA added: “The increases observed for dichloromethane are striking and unexpected; concentrations had been decreasing slowly in the late 1990s, but since then have increased by about a factor of two at sites throughout the globe.”

Dr Hossaini said: “It is uncertain what is driving this growth. However, it could be partly due to the fact that dichloromethane is used in the manufacturing process of some HFCs, the ‘ozone-friendly’ gases which were developed to replace CFCs. This would mean, ironically, that production of ozone-friendly chemicals is actually releasing some ozone-destroying gases into the atmosphere.”

Researchers have found a way to see light through opaque materials .

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Over the past decade, scientists have made huge progress in finding ways to see visible light through opaque materials, and now researchers in the US have found a way to see through a mouse’s ear in real time.

While we’ve been looking at objects inside the body using X-rays and ultrasound for several decades, the results are still pretty fuzzy and we often need to perform biopsies to really find out what’s going on at a deeper level.

But if we could shine visible light through the body, it would give us far clearer images than any other technique, and would mean we could do away with many intrusive surgeries. We could potentially even use laser light to treat inoperable tumours or brain aneurysms.

“Optical wavelengths interact strongly with organic molecules, so the reflected light is packed with information about biochemical changes, cellular anomalies and glucose and oxygen levels in the blood, writes Zeeya Merali for Nature.

The medical applications are obviously pretty huge, but unfortunately being able to see visible light through an opaque material is tough, because all of this interacting also means that the visible light will be absorbed or scattered by the material. And the light that’s absorbed is gone.

But over the past eight years, scientists have started using astronomical techniques in the hopes of salvaging that scattered light. And while we’re far off practical applications, there have been some very promising results.

Put very simplistically, the research is based on ‘un-scattering’ light. When astronomers look at the light from distant planets or stars, they know it’s been distorted by the atmosphere. To counteract this, they’ve created algorithms that reverse the scattering so that they can see the objects clearly. More recently, researchers have started using similar techniques to try to reverse the scattering caused by opaque materials.

Now a team from Washington University in St. Louis in the US has managed to visualise an ink-stained piece of gelatin pressed between the ear of an anaesthetised mouse and a ground-glass diffuser, using visible light.

To do this, they used a beam of ultrasound, which isn’t easily scattered like visible light is, and focussed it on a single point in the material. They knew that any optical light passing through this focussed point would shift its frequency slightly as a result of the ultrasound beam. They then set up a time-reversing mirror on the other side of the material, so that it would send back this frequency shifted visible light along the path it came in, visualising the target object on its way back. You can see a visual explanation of this in the graphic below, produced by the team over at Nature.

Unseen2Jasiek Krzysztofiak/Nature

This is a technique that’s been used for years, but in the past the light was passed back too slowly for it to be much use for living tissue. “Everything is in motion and we only have a millisecond-scale window to make an image,” lead author Lihong Wang explained to Merali.

But Wang and his team managed to speed it up. In their experiment, the visible light image was beamed back to the camera extremely quickly, in just 5.6 milliseconds, which “is fast enough for selected in vivo imagine”, he told Merali.

Their research, which was published in Nature, is a huge step towards being able to see what’s going on beneath our skin. Although Wang does add that: “moving from a mouse ear, which is relatively thin, to imaging human skin and flesh will still take a lot of extra work”.

Still, as Merali explains, this type of imaging has moved forward extremely quickly since 2007, when a team from the University of Twente in the Netherlands was first able to shine a beam of light through a ’solid wall’ of glass covered with white paint, and focus it on the other side. Their results were published in 2008.

“Just 10 years ago, we couldn’t imagine high-resolution imaging down to even 1 centimetre in the body with optical light, but now that has now become a reality,”Wang told Merali. “Call me crazy, but I believe that we will eventually be doing whole-body imaging with optical light.”

Aside from the medical benefits, this type of imaging technique also has some pretty important military applications, and could allow soldiers to carry an opaque shield that renders them invisible to their attackers, but that they can see through. “It’s not the same as being invisible, but it would allow you to see others while not being seen,” Mathias Fink, a physicist who, back in 1990, first pioneered the time-reversal technique that Wang and his team used, told Merali.

But Sylvain Gigan, a French physicist who also works in the field, added that all the researchers in this field are making sure to keep the applications clean. “When we tell people what we do, someone always asks if we’ll create a phone app to let people look through shower curtains,” he explained in the Nature article. “This is something that could be done with our technique – but we don’t intend to do it.”

Yeah seriously, don’t make it weird, scientists.

Protect Your Heart, Protect Your Brain

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What helps your heart can help your brain, too. Following a heart-healthy lifestyle can lower your chances of having a stroke, and it can also make a big difference in your mental abilities as you age.

In fact, getting plenty of physical activity, eating a healthy diet and other behaviors that strengthen your heart can have a profound effect on the way you think, how you act and what you remember.

“Most people don’t understand the connection between heart health and brain health, and as doctors we’re learning more every day,” said Ralph Sacco, M.D., chief of neurology at the Miller School of Medicine at the University of Miami and past president of the American Heart Association. “New studies have shown that the risk factors that can lead to heart disease and stroke, such as physical inactivity and obesity, also contribute to dementia, Alzheimer’s disease, memory loss and cognitive dysfunction.”

Here’s what happens: Those unhealthy behaviors can lead to narrowing of the blood vessels. That reduces blood flow to the brain, and leads to hardening of the arteries of the heart and the brain.

When your brain doesn’t get the blood flow it needs, it can begin to malfunction. As a result, Sacco said, you could experience problems thinking, trouble with memory, difficulty finding your way from place to place and deterioration in cognitive function. If blood flow to the brain is abruptly blocked, you could even have a stroke.

“People often associate memory loss with Alzheimer’s disease, and they think it can’t be prevented or treated,” said Sacco, the first neurologist to serve as president of the American Heart Association. “But controlling your risk factors for heart disease can make a difference in slowing its progression.”

Heart disease is the leading cause of death in America. Stroke ranks fourth, and it is also a leading cause of severe, long-term disability.

“Most of the time, like heart disease, it takes years of uncontrolled, unhealthy habits to wreak havoc on your brain, so it’s important to think about healthy habits as early as childhood and maintain them through adulthood and middle age,” Sacco said. “Many of these unhealthy behaviors translate to high blood pressure, diabetes and elevated cholesterol by the time you’re in your 50s.”

The High Blood Pressure Connection

“The one factor that is the strongest predictor of brain health is high blood pressure,” Sacco said. “It’s the most significant risk factor for stroke. It also has the most evidence suggesting that it leads to blockages of small arteries and impaired brain health.”

Many people don’t know they have high blood pressure because it has no visible symptoms, which is why it’s dubbed “the silent killer.” It can be controlled with lifestyle changes and high blood pressure medication, so visiting your healthcare professional to check your blood pressure is very important. Learn about high blood pressure and what you can do to control it.

Getting on the Right Path

It’s also important to discuss any cognitive problems you’re having with your healthcare provider.

“If you’re having trouble with memory or thinking, tell your doctor — and then tell your doctor again,” Sacco said. “We all have a little trouble when we age, like forgetting where we put our keys, but if your thinking problems seem more than usual your doctor may be able to find out if there’s really something wrong. You may need to be evaluated by a neurologist, or someone who specializes in cognitive issues.”

You might undergo testing to test how well your memory is working. You might also need to see a neuropsychologist, who can use brain teasers, puzzles and other tests to assess your cognitive function and compare it to other people your age.

The next step: Strive for a healthy lifestyle. This includes getting plenty of physical activity and following a healthy diet that includes lots of fruits, vegetables, whole grains, low-fat dairy, lean protein and fish. Maintaining a healthy body weight, not smoking, and managing your blood pressure, blood sugar and cholesterol are all critical.

Although healthy behaviors should ideally start early, it’s never too late. You can get a snapshot of your heart health and get help making improvements with My Life Check.

Fighting Heart Disease and Stroke

Researchers with the American Heart Association have long understood the connections between heart disease and stroke. In 1997, the organization created the American Stroke Association division to focus entirely on stroke. To learn more, volunteer or donate, visit  strokeassociation.org or heart.org.

Don’t Wait for Tesla’s Home Battery – Try This Off-Grid Battery Pack .

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Elon Musk made headlines this week announcing his plan to develop Tesla’s battery technology for home energy use.

Tesla’s mega factory will soon be churning out their super efficient lithium-ion battery packs for homes. The battery pack will reportedly be sold independently as well as being coupled with Musk’s decentralized green energy company Solar City.

solar

Even if you don’t have solar panels or a way to charge home battery banks, they can still pay for themselves quite quickly. Most electric companies charge a much lower rate at off-peak hours – as little as a third of the peak rate. So you can charge your battery pack when the rates are cheapest, and use that stored energy when the rates are highest.

Imagine saving two-thirds on your current electric bill. Most households would save a few thousand dollars a year. Battery banks would likely pay for themselves very quickly just using this method alone.  Add in a generator, solar panels, or wind mills to charge them and decentralized off-grid electricity seems quite practical.

However, since Tesla’s venture is at least six months away, I wondered what current options exist; and Tesla may have some stiff competition.

Aquion Energy manufactures its proprietary Aqueous Hybrid Ion batteries to provide affordable off-grid power storage. These eco-friendly batteries are made with saltwat.

watch the video. URL: https://youtu.be/aANBtotnsLI