Wednesday, August 04, 2010
The dreaded yellow flower
Silly Brits
"Wild swimming" is apparently becoming popular in cold, polluted British waterways. I did notice that Griff Rhys Jones seemed unusually keen on swimming in any murky brown stuff in his recent TV series about British rivers. Odd people.
Tuesday, August 03, 2010
Short answer: no
The Christian Science Monitor asks the question "is the moon really a 'been there done that' world?"
The answer, of course, is "no". There was a forum at NASA last month which went into the details of why, and you can read about it at the link.
Monday, August 02, 2010
Powered by the sun
It turns out that a particular salamander incorporates photosynthetic algae in its cells:
Kerney reported that these algae are, in fact, commonly located inside cells all over the spotted salamander's body. Moreover, there are signs that intracellular algae may be directly providing the products of photosynthesis — oxygen and carbohydrate — to the salamander cells that encapsulate them.This reminds me of the greenish, genetically engineered super bodies that were given to the aging soldiers in John Scalzi's "Old Man's War". If you're going to get into transhumanism, then incorporating chlorophyll would seem to be a good idea.
Babies at risk
Mary Beard discusses here on the practice in the Greco-Roman world of exposing unwanted babies. It's an unpleasant topic, but interesting.
Space airconditioning issue
I know very little about how the International Space Station works, despite my interest in all things spacey, but they have a cooling system that has gone on the blink:
The crew of the International Space Station have been forced to reduce power after half the cooling system suddenly shut down over the weekend.
Nasa officials insisted the three Americans and three Russians aboard were not in danger.
Urgent spacewalk repairs are being discussed for this week…
Flight controllers tried to restart the disabled ammonia pump early on Sunday but the circuit breaker tripped again.
Any repairs later this week almost certainly will involve replacing the faulty ammonia pump, a difficult job that would require two spacewalks, AP adds.
Two spare pumps are stored on the outside of the station.
Sunday, August 01, 2010
A noteworthy addition
China Hush is a good quality blog that seems to have a new post almost every day about some odd or unusual story from China, so I’ll add it to the blogroll.
Two recent examples of its content: the proposed “straddling bus”concept which, if ever implemented, would make the morning drive alone its route pretty disconcerting; and the jarringly cutesy animated abortion ad that shows that China and huge slabs of the West are, at least in certain aspects, still culturally very far apart.
Get it while it’s hot
In Japan, eel is seen as an energy reviving summer food. This Japan Times blog post notes that no one is sure how this idea developed, although one rather mundane theory is that it was an early marketing ploy by the fishmongers of the Edo period who were having trouble “moving” their eel catch. I hope the true reason is at least a little more romantic.
Anyhow, the other reason the article is blogworthy is because it discusses eel farming . (Most eel sold in Japan is farmed.) It had never occurred to me before that the odd life cycle of the eel does not make it an ideal candidate for farming:
So that's how they do it. But it would be having a significant impact on eel numbers in the natural waterways of Japan, wouldn't it?It’s impossible to grow unagi from eggs because despite the fact that unagi is designated as a fresh water fish, it lays its eggs in the ocean. (Anago, another eel species that is a popular dish in Japan, live in seawater their whole lives.) Their life cycle is the opposite of salmon, which lay eggs in freshwater but live their lives in the sea. In fact, no one knows precisely where unagi lay their eggs, though the most common theory is some place in the vicinity of the Marianas. After hatching the fry make their way back to Japan waterways and are caught in nets. These fry are then sold to unagi farms where they are raised to adulthood.
Germs and smarts
I missed this story when it came out in May, but I heard it being discussed on the radio today.
In mice at least, eating a common soil bacteria seems to make them learn faster. From the Science Daily report:
In the radio interview today, the researcher said they really have no idea whether the same thing happens in humans. But all the same, it's an intriguing idea that being too hygienic may not only be bad for allergies, but might make learning slower too."Mycobacterium vaccae is a natural soil bacterium which people likely ingest or breath in when they spend time in nature," says Dorothy Matthews of The Sage Colleges in Troy, New York, who conducted the research with her colleague Susan Jenks.
Previous research studies on M. vaccae showed that heat-killed bacteria injected into mice stimulated growth of some neurons in the brain that resulted in increased levels of serotonin and decreased anxiety.
"Since serotonin plays a role in learning we wondered if live M. vaccae could improve learning in mice," says Matthews.
Matthews and Jenks fed live bacteria to mice and assessed their ability to navigate a maze compared to control mice that were not fed the bacteria.
"We found that mice that were fed live M. vaccae navigated the maze twice as fast and with less demonstrated anxiety behaviors as control mice," says Matthews.
Add this to the “things I didn’t know were possible”list
Simon Dexter, a consultant at Leeds Teaching Hospitals and Meeta's surgeon, said that although it was a major operation it was possible to live without a stomach.
That’s from a BBC story about a couple of sisters in England who, due to their genetic susceptibility to stomach cancer, had theirs removed as a precaution. Unpleasant.
Friday, July 30, 2010
Greatest scandal of 20th century revealed
Behaviour modification required?
It indicated no big problem for either of us.
But due to a couple of mornings of dizziness on getting out of bed this week, I checked my own blood pressure again, and if this little machine is correct, it's up considerably since last year. But the readings it's giving for my wife are much worse, even first thing in the morning.
She's off to the doctor today to see if their machine agrees.
I should probably see my doctor too. There are several issues I can see that may need correcting in my current lifestyle:
1. Tony Abbott should stop improving his polling.
2. What? I can't spend a decade not bothering to get any particular exercise at all? I shake my fist at you fate. (Perhaps I shouldn't, that just made me dizzy.)
3. It's the evil influence of cheese. But is life with low fat cheese really worth living?
4. Salt. If, like me, your diet has a substantial Asian influence, salt is something that often comes in heavy doses. My impression is that nearly all men in Japan men go on blood pressure tablets from about the age of 42. (Their obligatory after work drinking sessions don't help too.)
5. Why am I cursed with a wife who is a talented baker, but with children who don't care for her cheesecakes, key lime pies (curse you, overly productive lime tree in the back yard), pecan pies, rhubarb cinnamon cakes, chocolate horns, etc? Hence, it becomes my duty to finish these desserts over 4 or 5 nights. (Neither my wife nor I actually consider ourselves to be fans of sugar or lots of cream; in fact if following an Australian recipe she often reduces the sugar by about one third and they still come out fine.) Seriously, I have asked my wife to stop making so many desserts, but she enjoys baking and resists my calls. It's a nightmare.
6. Blogging / the Internet. You mean I might be healthier by getting up and doing something, anything, physical, and going to bed a bit earlier. As well as avoiding irritants like the aggro commenters at Catallaxy? Well I'll be...
7. Lose weight. I'm pretty sure my calorie intake hasn't substantially increased over the last decade, but the kilograms surreptitiously increase anyway. We're not talking huge amounts, but photos catching me with a relaxed stomach now do embarrass me, and I know losing 5 - 6 kilos would put me in the normal BMI weight range. Maybe I should take up watching late night commercial TV for the latest exercise machine that I can pay off over four easy installments. Technology in them has improved over the last 10 years, hasn't it? In fact, the last time I lost weight was from a lingering stomach virus that reduced appetite for a good two or three weeks. Why can't that be an annual event?
8. Vitamin D. Yes, yes I am sure this is it. I get very little sun now. Happily, I see from an article in the New York Times that this is thought to be related to high blood pressure. I should be off to the pharmacy to see if vitamin D supplements will allow me to continue my sedate, sunless, salt, cheese and cheesecake eating lifestyle to continue.
Any other suggestions are welcome. Of course, we can also always hope the blood pressure machine is malfunctioning. That would be the best outcome of all.
Thursday, July 29, 2010
Optimism in pigs
Can you ask a pig if his glass is half full?
Quite a charming bit of research here:
In an experiment reminiscent of Pavlov's dogs, the Newcastle team taught the pigs to associate a note on a glockenspiel with a treat -- an apple -- and a dog training 'clicker' with something unpleasant -- in this case rustling a plastic bag.
The next step was to place half the pigs in an enriched environment -- more space, freedom to roam in straw and play with 'pig' toys -- while the other half were placed in a smaller, boring environment- no straw and only one non-interactive toy.
The team then played an ambiguous noise -- a squeak -- and studied how the pigs responded. Dr Douglas said the results were compelling.
"We found that almost without exception, the pigs in the enriched environment were optimistic about what this new noise could mean and approached expecting to get the treat," she said. "In contrast, the pigs in the boring environment were pessimistic about this new strange noise and, fearing it might be the mildly unpleasant plastic bag, did not approach for a treat.
Crabb on those leaks
Rudd's only response yesterday was via a statement from a spokesperson.
Would he not be capable of making a media appearance, not to answer questions, but simply to deny in person that he is the source of the leaks, and deny knowledge of the source, and to publicly call on the leaker to desist and get behind the re-election of a Labor government?
In any event, such anonymous leaks may perversely work (to a degree) in Gillard's favour, at least if their content is as ultimately unimportant as yesterday's. Everyone (even Laurie Oakes, I heard somewhere, although I don't know how to track down his articles on line) seems to agree that Gillard's come out fighting approach worked for her yesterday.
Real prediction vindicated
a. a lengthy guest post by "Tamino" reviewing a book on the hockey stick controversy, and explaining in great detail why McIntyre is wrong. In comments, there is a full blown fisking of the Judith Curry's quasi-defence of the book and McIntyre, and she does not come out of it well.
b. a post noting the surprisingly accurate predictions of global warming from the mid 1970's by Wally Broecker, who even coined the term "global warming". The article notes:
To those who even today claim that global warming is not predictable, the anniversary of Broecker’s paper is a reminder that global warming was actually predicted before it became evident in the global temperature records over a decade later (when Jim Hansen in 1988 famously stated that “global warming is here”).He wasn't the first to predict warming from CO2, though:
Broecker was not the first to predict CO2-induced warming. In 1965, an expert report to US President Lyndon B. Johnson had warned: “By the year 2000, the increase in carbon dioxide will be close to 25%. This may be sufficient to produce measurable and perhaps marked changes in climate.” And in 1972, a more specific prediction similar to Broecker’s was published by the eminent atmospheric scientist J.S. Sawyer in Nature (for a history in a nutshell, see my newspaper column here).For all the skeptics who thought it was only global cooling being considered in the mid 70's, this is well worth reading.The innovation of Broecker’s article – apart from introducing the term “global warming” – was in combining estimates of CO2 warming with natural variability. His main thesis was that a natural climatic cooling
The latter turned out to be correct.has, over the last three decades, more than compensated for the warming effect produced by the CO2 [....] The present natural cooling will, however, bottom out during the next decade or so. Once this happens, the CO2 effect will tend to become a significant factor and by the first decade of the next century we may experience global temperatures warmer than any in the last 1000 years.
Past ocean acidification considered
It took at least 25,000 years for the new acidity levels reached in the surface waters to transfer to deeper waters, according to the research—and the ocean took 75,000 years to reach its peak acidity for that episode, as well as at least 160,000 years to recover. The length of this episode derives "most probably because several CO2 pulses [volcanic eruptions] contributed to ocean acidification," Erba says. Further, she plans to examine other high CO2 events in the geologic record to see "if the same causes—excess CO2, global warming, ocean acidification—trigger similar effects on marine calcifiers at different times."Here's the crux:
But the 25,000-year time lag between acidification of the surface waters and deeper waters is mysterious, points out geoscientist Timothy Bralower of The Pennsylvania State University, who was not involved in this study. "In the modern ocean, a similar input of carbon would involve a lag on the order of centuries," he notes. "So something is very different." And the nannoconids begin to disappear even before the fossil record indicates lighter volcanic carbon isotopes—in other words, presumably before the actual acidification.
"The current rate of ocean acidification is about a hundred times faster than the most rapid events" in the geologic past, notes marine geologist William Howard of the Antarctic Climate and Ecosystems Cooperative Research Center in Hobart, Tasmania. Plus, the direct impacts of global warming may complicate the picture—just as modern coral suffer from increased bleaching thanks to warmer ocean temperatures as well as the reduced carbonate exoskeleton–building capacity brought on by ocean acidification. Bralower adds: "The big question is whether modern species will be able to adapt to what I expect will be much more rapid pH reduction in coming centuries."
Phytoplankton worry
Something to worry about? Well, yes:Phytoplankton activity fluctuates widely according to season and location, making long-term monitoring of trends difficult. An earlier study2, based on satellite observations of ocean colour, suggested a link between climate variability and ocean productivity, but this was limited to observations from 1997 to 2006. Boris Worm, a marine biologist at Dalhousie University in Halifax, Canada, and his team have now combined satellite-derived observations of phytoplankton with historical shipboard measurements stretching back to the pioneering days of oceanography.
The research reveals an unsettling centennial downwards trend, superimposed on shorter-term variability. The scientists found that the average global phytoplankton concentration in the upper ocean currently declines by around 1% per year. Since 1950 alone, algal biomass decreased by around 40%, probably in response to ocean warming — and the decline has gathered pace in recent years.
"Clearly, 40% is a huge number," says Paul Falkowski, an oceanographer at Rutgers University in New Brunswick, New Jersey. "This implies that the entire ocean system is out of steady state, slowing down.
"This is severely disquieting," adds Victor Smetacek, a marine biologist at the Alfred Wegener Institute of Polar and Marine Research in Bremerhaven, Germany. "One must really digest the very magnitude of this decline and its possible implications."The culprit is believed to be ocean warming:
In most regions tested, the phytoplankton decline seems to be the result of a 0.5–1.0 °C warming of the upper ocean over the past century. The warming leads to enhanced vertical 'stratification' of ocean layers, thus limiting the supply of nutrients from deeper waters to the surface.No one is pointing the finger at ocean acidification yet, and (from memory) experiments with bubbling CO2 through phytoplankton have had mixed results. But there was this story recently that increased acidification may affect the availability of iron, which phytoplankton need to grow well. (There is more detail on that study at my earlier post.) So, I wonder if acidification over the last century is part of the explanation.But ocean warming does not explain reduced productivity in regions, including the Arctic Ocean, where algal growth is mainly constrained by sunlight. So scientists must try to find out what other drivers, such as changes in wind and ocean circulation, might force the decline, says Falkowski.
Wednesday, July 28, 2010
Fiddling with algae
The New York Times reports on a lot of work being done to genetically alter algae to make it better as a potential large scale source of biofuel. This is being taken very seriously:
“There are probably well over 100 academic efforts to use genetic engineering to optimize biofuel production from algae,” said Matthew C. Posewitz, an assistant professor of chemistry at the Colorado School of Mines, who has written a review of the field. “There’s just intense interest globally.”Algae are attracting attention because the strains can potentially produce 10 or more times more fuel per acre than the corn used to make ethanol or the soybeans used to make biodiesel. Moreover, algae might be grown on arid land and brackish water, so that fuel production would not compete with food production. And algae are voracious consumers of carbon dioxide, potentially helping to keep some of this greenhouse gas from contributing to global warming.
But some people are a little concerned:
At a meeting this month of President Obama’s new bioethics commission, Allison A. Snow, an ecologist at Ohio State University, testified that a “worst-case hypothetical scenario” would be that algae engineered to be extremely hardy might escape into the environment, displace other species and cause algal overgrowths that deprive waters of oxygen, killing fish.
And I guess I didn’t realise how important the humble green scum really is:
“About 40 percent of the oxygen that you and I are breathing right now comes from the algae in the oceans,” the genetic scientist J. Craig Venter said at a Congressional hearing in May. “We don’t want to mess up that process.”
Corals feel the heat (and the weed)
Sea surface temperatures in the Red Sea are routinely very high, I believe, but there are corals there that cope nonetheless. There’s a convincing sounding study in Science that indicates their tolerance is approaching its limits:
In other coral news, it's reported today that seaweed is encroaching on a significant number of reefs in the Great Barrier Reef, but the reason is said to be poor water quality. However, I think it’s also worth noting that ocean acidification would be likely to increase that problem.Sea surface temperature (SST) across much of the tropics has increased by 0.4° to 1°C since the mid-1970s. A parallel increase in the frequency and extent of coral bleaching and mortality has fueled concern that climate change poses a major threat to the survival of coral reef ecosystems worldwide. Here we show that steadily rising SSTs, not ocean acidification, are already driving dramatic changes in the growth of an important reef-building coral in the central Red Sea. Three-dimensional computed tomography analyses of the massive coral Diploastrea heliopora reveal that skeletal growth of apparently healthy colonies has declined by 30% since 1998. The same corals responded to a short-lived warm event in 1941/1942, but recovered within 3 years as the ocean cooled. Combining our data with climate model simulations by the Intergovernmental Panel on Climate Change, we predict that should the current warming trend continue, this coral could cease growing altogether by 2070.