Day: 09/14/2012

Australia’s oceans are changing.

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Launched on 17 August, the 2012 Marine Climate Change in Australia Report Card demonstrates that climate change is having significant impacts on Australia’s marine ecosystems.

The report card provides information about the current and predicted-future state of Australia’s marine climate and its impact on our marine biodiversity. The report card also outlines actions that are underway to help our marine ecosystems adapt to climate change.

“Although there are some concerning findings in the 2012 report card, the information we’ve compiled is helping to ensure that ocean managers and policy makers are best placed to respond to the challenge of managing the impact that climate change is having on these systems.”

‘Australia has some of the world’s most unique marine ecosystems. They are enjoyed recreationally, generate considerable economic wealth through fisheries, aquaculture, and tourism, and provide irreplaceable services including coastal defence, oxygen production, nutrient recycling and climate regulation,’ Project leader CSIRO’s Dr Elvira Poloczanska said.

‘Although there are some concerning findings in the 2012 report card, the information we’ve compiled is helping to ensure that ocean managers and policy makers are best placed to respond to the challenge of managing the impact that climate change is having on these systems.’

Key findings show:

– warming sea temperatures are influencing the distribution of marine plants and animals, with species currently found in tropical and temperate waters likely to move south

– new research suggests winds over the Southern Ocean and current dynamics are strongly influencing foraging of seabirds that breed in south-east Australia and feed close to the Antarctic each summer

– some tropical fish species have a greater ability to acclimatise to rising water temperatures than previously thought

– the Australian science community is widely engaged in research, monitoring and observing programs to increase our understanding of climate change impacts and inform management

– adaptation planning is happening now, from seasonal forecast for fisheries and aquaculture, to climate-proofing of breeding sites for turtles and seabirds.

Led by CSIRO, more than 80 Australian marine scientists from 34 universities and research organisations contributed to the 2012 report card. The report card draws on peer-reviewed research results from hundreds of scientists, demonstrating a high level of scientific consensus.

‘Our knowledge of observed and likely impacts of climate change has greatly advanced since the first card in 2009,’ Dr Poloczanska said.

Aspects of marine climate which have been analysed include changes in sea temperature, sea level, the East Australian Current, the Leeuwin Current, and El Niño-Southern Oscillation.

Marine biodiversity assessed for the report card include impacts on coral reefs; tropical, temperate and pelagic fish; marine mammals; marine reptiles; seabirds; mangroves; tidal wetlands; seagrass; macroalgae; marine microbes; phytoplankton and zooplankton. The two new sections included in the 2012 report card focus on the smallest and largest organisms in the oceans: microbes and whales.

The project has been funded by the Australian Government Department of Climate Change and Energy Efficiency, through the National Climate Change Adaptation Research Facility’s Marine Biodiversity and Resources Adaptation Research Network, the Fisheries Research and D

evelopment Corporation, and CSIRO’s Climate Adaptation National Research Flagship.

Source: Science Alert

 

 

Structures may cause jellyfish blooms.

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Human-made structures such as harbours, tourist facilities, oil rigs and aquaculture farms provide ideal sanctuaries for jellyfish polyps to flourish and may explain an apparent increase in jellyfish blooms in many coastal waters around the world.

That’s the conclusion of a new study published by a group of international researchers, including lead author Winthrop Professor Carlos Duarte, Director of the Oceans Institute at The University of Western Australia.

Their paper “Is global ocean sprawl a cause of jellyfish blooms?” appears in the journal Frontiers in Ecology and the Environment.

Professor Duarte said most theories that seek to explain increased jellyfish blooms focus on jellyfish at their more mature swimming stage and factors such as a lack of predators or competitors due to overfishing.

But the new study examined the tiny polyp phase of jellyfish and found they congregate in millions on the underside of human-made structures.

“We call this new proposition the ‘Trojan Horse‘ hypothesis,” Professor Duarte said.

“The proliferation of artificial structures such as harbours, shipping facilities and aquaculture structures provides a habitat for jellyfish polyps and may be an important driver in explaining the global increase in jellyfish blooms.”

Professor Duarte said jellyfish larvae typically settle on a hard surface and grow into polyps as part of a colony.  The polyps are generally inconspicuous because they are very small – usually only a millimetre or so in length.

The study examined polyps growing on a variety of man-made structures around the world – including in Japan, Britain, Spain and Slovenia – and looked under docks, piers, pontoons and artificial reefs, and on the underside of oysters attached to piers.

“Jellyfish polyps existed on the underside of such artificial structures at densities of more than 10,000 individuals per square metre, and sometimes up to 100,000 per square metre,” Professor Duarte said.

Research was also conducted in Chesapeake Bay in the US and in a laboratory with a Mediterranean jellyfish species to examine how larvae settled on oyster shells, flagstones and 16 other surfaces, including bricks, ropes, cans, wood, concrete and plastic.

Source: Science Alert

 

 

Pregnancy-related cancers on rise.

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The rate of pregnancy-associated cancer is increasing and is only partially explained by the rising number of older mothers according to research led by the University of Sydney.

The researchers say improved diagnostic techniques, detection and increased interaction with health services during pregnancy may contribute to the higher rates of pregnancy-associated cancer.

The findings, co-authored by Dr Christine Roberts from the Kolling Institute at Sydney Medical School, were recently published in BJOG: An International Journal of Obstetrics and Gynaecology. Cathy Lee, a Masters student in Biostatics at the University, is lead author of the study.

“The genetic and environmental origins of pregnancy-associated cancers are likely to pre-date the pregnancy but the hormones and growth factors necessary for a baby to develop may accelerate the growth of a tumour,” Dr Christine Roberts said.

The Australian study looked at 1.3 million births between 1994 and 2008. The rate of pregnancy-associated cancer, where the initial diagnosis of cancer is made during pregnancy or within 12 months of delivery, was compared to pregnant women without cancer (using the same parameters).

It found that over a 14-year period the incidence rate of pregnancy-associated cancer increased from 112.3 per 100,000 to 191.5

“Although this represents a 70 percent increase in cancers diagnosed during or soon after pregnancy it is important to note that cancer remains rare affecting about two in every 1000 pregnancies,” Dr Roberts said.

Although the age of the mother is a strong risk factor for cancer, increasing maternal age explained only some of the increase in cancer occurring.

“Pregnancy increases women’s interaction with health services and together with improved techniques for detecting cancer the possibility for diagnosis is therefore increased,” Dr Roberts said.

The most common cancers detected were skin melanomas, breast cancer, thyroid and other endocrine cancers, gynaecological and lymphohaematopoeitic cancers. The high incidence of melanoma may relate to the fact Australia has the highest incidence of melanoma in the world.

The study also looked at pregnancy outcomes and found that cancer during pregnancy was associated with a significantly increased risk of caesarean section and planned preterm birth which may be to allow cancer treatment to commence.

Importantly there was no evidence of harm to the babies of women with cancer – they were not at increased risk of reduced growth or death.

Source: Science Alert

 

 

Rainfall decline in Australia.

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Ice cores reveal Australian  rainfall decline Researchers from the ACE CRC and the Australian Antarctic Division have found evidence from ice cores of a long term decline in average annual rainfall in eastern Australia, with records revealing that rainfall since about 1920 is below the average of the past 1000 years.

Australia’s instrumental climate records extend back only about 100 years and show an apparent decline in eastern Australian rainfall. However rainfall in eastern Australia is highly variable, and the significance of the decline can only be assessed when compared with a much longer record.

ACE CRC glaciologist Dr Tessa Vance and colleagues from the Australian Antarctic Division (AAD) and UTAS have obtained the 1000-year record from ice core data. The research, published in Journal of Climate, shows a direct correlation between the instrumental eastern Australian rainfall record and sea salts deposited by winds at Law Dome in East Antarctica over the past 100 years. The 1000-year-old Law Dome sea salt proxy provides the longest rainfall record yet for eastern Australia.

“The El Niño-Southern Oscillation, or ENSO, climate mode predominantly drives rainfall in eastern Australia and is one of the factors that affects winds in the Southern Ocean,” Dr Vance said.

Unlike many other continents, such as North America and Europe, Australia generally lacks suitable climate proxies (such as tree rings) for rainfall prior to the instrumental record. “We weren’t expecting such a strong correlation between two areas this far apart. Normally proxy records come from the region that you are trying to describe,” Dr Vance said.

The proxy record shows that the dry period since the 1920s is similar to a dry period from 1000-1260 AD. Scientists attribute both dry periods to either stronger or more frequent El Nino events. In El Niño-like years, summertime winds in the Southern Ocean are reduced, leading to lower than average concentrations of salts in the ice core. In La Niña-like years, the opposite occurs, with higher summertime winds causing higher concentrations of salts.

Dr Tas van Ommen leads the AAD Climate Processes and Change Program and is a co-author on the study. “This work builds on a 2010 study from the AAD which identified other mechanisms linking Antarctica with the drought in Western Australia, and it shows how important Antarctic climate studies are to understanding climate processes in Australia and the Southern Hemisphere,” he said.

Future research will work towards understanding whether the current dry period had similar climate drivers to the period from 1000-1260 AD. The record will also be extended back another 1000 years, increasing understanding of the Australian climate for the past 2000 years.

Source: Science Alert

House of Water’ taps market for designer agua.

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MEXICO CITY – The sign outside reads Casa del Agua and below it, el agua local: local water.

This could scare away a customer or two, given that this is Mexico City, where even the rain isn’t clean and tap water is best avoided. But the capital’s newest watering hole takes its water very seriously and purports to offer the purest drink around.

Owner Bosco Quinzanos envisions the Casa del Agua as an answer, however incomplete, to Mexico City’s fraught relationship with water: In this often rainy metropolis of more than 20 million, there always seems to be either too much or too little.

Employing an elaborate purification system, which includes a period of “harmonization” in the final stage, Casa del Agua bottles rainwater. But the month-old business sells something more conceptual: ecology, sustainability, harmony.

“We deliver the highest quality water in Mexico,” Quinzanos said while relaxing in a wrought iron chair on the shop’s roof garden, which is designed to capture what it can of the capital’s average 34 inches of rain annually – just slightly less precipitation than soggy Seattle.

The rainwater filters through a teak patio and garden of cherry, orange and lime trees and carpets of lavender, mint and thyme into storage tanks. The water then passes through increasingly fine filtration systems and distillation machines. After that, the water is pure. Bent on adding value, the Casa del Agua runs the purified water through a process to restore minerals and ionize it.

Then comes “harmonization,” based on Japanese author Masaru Emoto’s unproved hypothesis which holds that the environment – including music and prayer – can affect water on a structural level.

Quinzanos professes his faith in the “harmonization” process. Before bottling, the purified water runs over stones engraved with the words “love,” “respect” and “gratitude” and is exposed, in bottles, to soothing classical music playing in the store. Whatever its benefits (or not) to the consumer, the concept resonates with a Mexican market’s preoccupation with buena onda – good vibes – offering a promotional plus to what is essentially an ecological project.

Laura Casanova listened to the store manager’s explanation of the process, from purification to harmonization, and became convinced to buy a returnable glass bottle for 30 pesos, or $2.30. A refill costs 10 pesos, or 77 cents.

“It’s an incredibly novel concept,” she said in flawless English. “Using rainwater — it’s unheard of. It’s like designer water, taken another notch up.”

The bottles, branding and design of the shop itself come from the team that created the typography and interior of Mexico’s fast-expanding, homegrown coffee chain, Cielito Querido. In the Casa del Agua, a palette of black, white and cream and the branding on bottles seems to echo the ink-on-paper sketches of bizarre 19th century inventions.

Graphic designer Nacho Cadena describes the design as “transparent … clean and salubrious.”

“It’s inspired by artisan processes, a brand that evokes nostalgia,” he said.

On the rooftop, Quinzanos took a swig from one of the swing-top water bottles.

“It has no taste because it is very pure,” he said.

Parts of Mexico City flood with nearly every storm as a perennially clogged drainage system fills up and runoff spills into ground floors and down subway stairs. Other days, turning on the faucet yields only the gurgle and hiccup of pipes that have run dry as the city periodically shuts off water to one or another neighborhood.

When the rain runs out, the Casa del Agua taps water from the city system, but the goal is to rely on nature, Quinzanos said.

The clouds overhead grew dark blue and heavy, and a line of laundry on a nearby building flapped in the sudden wind. It appeared the sky would deliver.

Source: Smart Planet

What is the electromagnetic spectrum?

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Visible light forms part of the electromagnetic spectrum. So do emissions from TV and radio transmitters, mobile phones and the energy inside microwave ovens.

The X-rays used in diagnostic imaging and the materials used in advanced positron emission tomography scanners (PET) also form part of this amazing range of radiations which share some features in common.

Why electromagnetic?

As the name implies, they have electric and magnetic fields associated with them. Although it is a bit complicated to demonstrate these fields in the case of light and X-rays, it is quite easy to picture with radio-waves.

Consider the wires shown below, in which an electric charge has been placed at the tips as shown (don’t worry about the technicalities – it’s a bit like the static charge that appears in dry hair when combed vigorously).

This pair of charges (plus and minus) sets up an electric field, with the imaginary field lines shown. If now the charge is allowed to flow along the wire, this will set up a magnetic field as shown by the concentric circles.

A long way away from this arrangement (which is called a dipole antenna) the electric and magnetic fields are at right angles. If the charge generator alternates between having plus and minus at the top, the field direction will also alternate, as shown, with a time period T between positive-going peaks (1 cycle).

Since the generator has to do work to alternately put charge one way and then the other, this work (energy) is constantly streaming from the wires, out into the surrounds.

This is why it is called “radiation”, because it is radiating outwards. In fact, at a particular point, the fields will appear to be moving past at a particular speed.

This speed is the velocity of light (which in vacuum is 3 x 108 m/s, or 300,000 km/s). Even if the electromagnetic waves are invisible radio-waves or X-rays, for example, they still go at this speed. The energy spreads out over a larger and larger area as it moves away from the source, often the same in all directions.

In this case, the area it spreads over is the area of a sphere (4 r2 ), thus there is an “inverse square law” of energy density, since for a particular area (1 cm2 , say) the energy falls by a factor of 1/r2.

The other thing to notice is that if the wave is travelling at the speed of light ( c ) and the time for 1 cycle is T, then the length of 1 cycle (wavelength) is c x T. The table below shows the wavelengths of typical forms of radiation.

Why spectrum?

A spectrum is what you get by passing light through a glass prism – the white light is split into its component colours.

Imagine a magic prism which could do this for the entire range of electromagnetic waves. Such a device does not exist, but if it did, wavelengths ranging from thousands of kilometres (Extremely Low Frequency or ELF) through to sizes smaller than an atom would be produced.

For the radio-frequencies, there is a device, called a spectrum analyser, which does this for particular ranges. Modern mobile telephony uses “spread spectrum” technology, so a network analyser can be used to measure the amount of radio frequency (RF) energy spread out over a range of frequencies, much in the same way a glass prism does for light.

Why ionising and non-ionising?

Although both RF and X-rays are referred to as radiation, they interact with the body in a fundamentally different way: X-rays can remove electrons from atoms (turning them into ions, hence ionising), whereas RF cannot (hence non-ionising).

The reason that exposure to high intensities of X-rays (and other rays, such as gamma rays and X-rays) is linked to cancer, is that the ionisation can lead to changes in genetic material which cannot be repaired.

Non-ionising radiation has not been shown to do this. The main effect of RF radiation is to cause heating (as in a microwave oven). Lower frequencies (such as ELF) can lead to the direct stimulation of nerves and muscles, rather than heating.

Using computer models of the human body (consisting of elements as small as 1mm cubes, and with the electrical properties of different types of tissue represented appropriately) it is possible to compute how much increase in temperature there will be in the parts of the head next to a mobile phone handset, when in operation.

With blood-flow properly included, the increase in temperature is much less than 1ºC, in fact much less than the natural variation in temperature over a 24-hour cycle.

Natural vs “unnatural”

There are now many who are concerned about “electrosmog” – the soup of emissions from consumer electronics that, to a greater or lesser extent, we are all exposed to (such as wireless routers, Bluetooth connections, smart meters).

It is perhaps comforting that, even before the advent of modern technologies, we were still exposed to various forms of electromagnetic radiation, principally from the sun (ranging from ultraviolet, through visible to infra-red), but also from natural (ionising) radioactivity, from various rocks such as granite and uranium ores.

In addition to the relatively strong magnetic field of Earth, various atmospheric phenomena, such as lightning, produce ELF and RF fields.

Remember also that the heart, brain, muscles and nerves all have electrical currents associated with them: diagnostic systems such as the well-known electroencephalogram measure body-generated electric fields and more advanced systems also measure the magnetic fields generated by the brain and other organs.

There is no evidence that the introduction of radio broadcasting at the start of the 20th century was associated with an increased incidence of disease. Life expectancies in general have increased significantly over the last 100 years, with a contribution from superior diagnostic procedures (computed tomography – which uses X-rays; and magnetic resonance imaging – which uses RF and strong magnetic fields) that exploitation of the electromagnetic spectrum has allowed.

Source: Science Alert

Gel stretches to 21 times its length, could replace cartilage?

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Wow.

This gel is made of 90% water, and yet it can stretch to 21 times its resting length without breaking. Even a rubber band only stretches to six times its resting length.

Since it’s compatible with the living tissue, it could someday be used in the body, such as to replace cartilage (such as in kneecaps), spinal discs or other tissues. Similar such hydrogels are currently used to make contacts.

But this hydrogel is the stretchiest, toughest one ever.

“It’s the toughest hydrogel ever reported, we believe,” said Zhigang Suo, a mechanical engineer at Harvard University and senior author of the paper, which was published in Nature. “So far, nobody has challenged this claim.”

What’s it made of?

Gels are usually brittle. In order to create a stretchy gel, engineers have to combine gels whose structures dissipate energy together. Usually, the combination is a strong, stiff gel that has densely packed polymers and another one with a loosely packed polymer network.

The way these work together is that if the stiff gel cracks, meaning its chemical bonds get broken, then the looseness in the second gel reduces the breakage.

Even gels made this way get broken repeatedly, causing the gel to get weaker.

To solve the problem of fatigue, Suo and his colleagues used, for their second gel, one with polymers linked by calcium ions; ionic bonds can re-form easily.

If it seems like a crack is about to form, the calcium ions “unzip,” to dissipate energy, and that allows the covalent bonds from the other gel to remain intact.

As the Los Angeles Times puts it, “Later, when the stress subsides, the calcium ions can return back to their initial positions, ‘re-zipping’ the ionic bonds back together.”

This new self-healing hydrogel can take up to nine times more mechanical stress than cartilage, making it about as good as natural rubber. And it maintains its elasticity and toughness even after being stretched multiple times. The only thing it needs is some time between stretches for the calcium to re-zip.

It’s so self-healing, in fact, that the researchers showed that if they cut a two-inch crack in the gel, it can still stretch to 17 times its starting length.

And don’t even try ripping it apart with your bare hands. You can’t.

Source: Smart Planet

Why algorithms need humans to predict the weather?

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History is rich with intellectuals who have revered theories of determinism; ideas that suggest if we could only know every facet of a situation, every molecule of the landscape, we could predict and even shape future political, economic, and cultural outcomes.

But when it comes to the weather, forecasters long ago gave up any hope of cataloging all of the variables that could impact rainfall in Seattle, or the arrival of a cold front in New York. At least that’s what Nate Silver reports in his new book, The Signal and the Noise: Why So Many Predictions Fail — but Some Don’t, an excerpt of which was adapted for a recent article in The New York Times Magazine.

If you go by Silver’s account, weather forecasting is something of a dark art. Despite all of the measurements, modeling, and statistical analyses, the weather business relies as much on human insight as it does on computer programming. This is best evidenced by the National Weather Service’s own historical records. According to the agency’s data, a combination of human and computing power creates the most accurate weather forecasts. People improve accuracy levels for precipitation and temperature forecasts by about 25 percent and 10 percent respectively over forecasts done by computers alone.

In other words, the algorithms haven’t bested us yet.

Even as modern futurists envision a time when computers will out-think people, it turns out that there may always be a role for the human mind. In weather forecasting, even the most sophisticated computer modeling systems disagree with each other all the time. It’s up to the people studying those models to illuminate nuance and apply additional context; whether that means knowing how best to weight the variables that determine where a storm is headed, or that morning fog in the northeast tends to dissipate quickly when the wind is blowing in a particular direction.

As powerful as computers are, they can’t “see” everything. And they’re not necessarily as good as humans at knowing when and where to look for more information. Our obsession with big data, and the quantification of industries – finance, advertising, space – can sometimes blind us to the fact that human perception and insight, fuzzy and imprecise though they may be, are still critical to society’s progress. Maybe in the future they’ll laugh at our fixation with numbers. Or maybe they’ll simply recognize better than we seem to that numbers are only part of the equation.

Source: Smart Planet

Why I support the New York City soda ban?

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In 2010, when lawmakers in my then-homestate of Washington proposed a soda and candy tax, I opposed the idea. My aversion stemmed from knowledge of a stipulation in food stamp use: state-issued food benefits can’t be applied towards taxable items. So people who depended solely on food stamps for sustenance would be denied the option of purchasing candy or soda. While that restriction might have ultimately been “good” for their health, I found the idea of instituting a public health measure most targeted towards the poor distasteful.

I don’t see that problem with my current home city’s ban on large sodas, which the New York City Board of Health approved earlier today. Why? Sugary drinks are a leading cause of obesity because they have a secret weapon other high-calorie items don’t. They’ve got an unfair advantage on us, and the soda ban is a step in the right direction to combat that.

Here’s the deal — beverages don’t activate the same “full” sensation that food does. Eating 800 calories may leave you stuffed, but drinking 800 calories in soda has far from the same effect.

In an article I wrote on the topic for Dr. Oz’s website I explain that our bodies sense beverages and food using completely different mechanisms. If you eat 800 calories, those calories impact the body and the brain in such a way that you’ll reduce your consumption of other foods. However, when calories come in the form of a liquid—even if the calorie amount may be the same as the solid food—research shows that you don’t eat less later on. Drinking 800 calories before your meal doesn’t translate to eating 800 less calories during your meal.

We don’t sense fullness from beverages because humans didn’t evolve with a need for that skill. “One could speculate,” Richard Mattes a professor of food and nutrition at Purdue University told me for the Dr. Oz article, “that evolutionarily, after weaning, we really didn’t have energy-yielding beverages. Yes, we’ve had beer and alcohol for 12,000 years, but in the scope of evolutionary time that’s a trivial time frame. Throughout most of human evolution water was the beverage.” So for most of human history there was little need to judge calories in drinks because, aside from breast milk, calories in drinks just didn’t exist.

Super-sized sodas prey on that poor judgement, filling us with calories we can’t even sense we’re consuming.

As far as concerns from the soda sellers, I don’t see the giant soda ban (which limits sugary drinks at restaurants, street carts, and movie theaters to sixteen ounces) as a significant threat. Just look at the way coffee chains have gotten away with shrinking their drink sizes. Retailers can still sell “large” sodas for the same price, the cup will just have to be smaller. And if customers want more than sixteen ounces of soda, they’ll have to buy two drinks, giving the retailer more money than they would have if they could have bought one giant soda.

Yes, ounce per ounce the soda distributors will likely sell less soda to NYC retailers due to this ban. But ultimately, is this really an industry whose interests should be driving our health policies?

Source: Smart Planet

OTC Topical Pain Relievers Pose Burn Risk .

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Over-the-counter topical muscle and joint pain relievers containing capsaicin, methyl salicylate, or menthol (e.g., Bengay, Icy Hot) may cause serious chemical burns, according to the FDA.

A review of two adverse drug event databases, as well as the medical literature, found 43 reports of burns linked to these products. Those containing menthol were the most likely to cause second- and third-degree burns.

The FDA advises clinicians to warn patients about the burn risk and to provide guidance on using the products appropriately. In particular, the pain relievers should not be applied to broken or damaged skin; the area should not be bandaged tightly; and heating pads should not be used.

Adverse events linked to these pain relievers should be reported to the FDA’s MedWatch program, the agency says.

Source: FDA MedWatch safety alert