I haven't spent much time outside the confines of the conference - apart from the sun-drenched stroll between the convention centre and another venue, the Sheraton, about a mile away.
So yesterday I thought, enough is enough. I went for a run over the Benjamin Franklin bridge with Neil Gussman, PR guy for the Chemical Heritage Foundation, and US army sergeant.

The run was amazing, the pedestrian bridge is much higher than the cars and the cars are much, much, much higher than the Delaware river. If you need to escape the city, you could do a lot worse than this towering piece of metal engineering.

Today I took another trip to CHF, to check out their new, and very impressive, gallery. It's still under construction, but the floor-to-ceiling interactive periodic table installment (made in part by he of the Periodic Table Table fame, Theo Gray) is already in place. It is awesome. Videos run for each element, and the whole thing cascades from the huge 2-storey ceiling to the floor on a massive array of TV screens.

The new galleries are also hosting a travelling art exhibit, molecules that matter. This is a collection of artists representations of 10 selected molecules that have influenced society in the past 100 years. Apparently the choice of molecules upset some staunch organic chemists. I can't see why. You should pop over and see if you're getting cabin fever in the conference.

Posted by Katharine Sanderson on August 20, 2008
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The answer to the question posed above isn't clear. I went to a session about plastic devices that could be used as solar cells instead of expensive silicon, hoping to hear a breathrough was nigh. Sadly i was wrong. Advances in plastics that can capture light over a useful wavelength, that can separate the charge into electrons and holes, that can carry that charge and finally, do something useful with it are being made. But slowly.

Talking in the session was Fred Wudl, who was first to develop fullerene/polymer systems as photovoltaic cells. It seems that the system he hit upon first up has been hard to beat, at least according to Mats Andersson, from Chalmers University of Technology, Gothenburg, who was also speaking in the session.

Percentage power conversion efficiencies remain low. The very best results are around 5%, and these tend to be from a single, meticulously prepared sample - a long way from a manfacturable, large scale printing porcess that is hoped for. To be really viable, a system that is 10% efficient is needed, or a slightly less efficient, but very cheap plastic material that can be made to cover a large area. But still, despite lots of tinkering with the polymers in the systems, the best that Andersson presented was 2.8% efficiency. Manpreet Kaur, from Virginia polytechnic presented a system with an efficiency of 1%.

The systems rely on the electron-transporting porperties of a polymer, and the hole (absence of electron) transporting properties of the fullerene groups. The main way to change these systems is altering the polymer groups.

The field is gaining strength, however. One company, Konarka, is claiming that it will have a flexible, efficient, solar cell plastic available by the end of the year. We shall have to wait and see.

The session certainly generated interest, but i can't help think that the efficiencies are going to remain low for a while yet. Perhaps next year, if Konarka has delivered, academics will have joined them in finding a more efficient system.

Posted by Katharine Sanderson on August 20, 2008
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At the general poster session the other night I was delighted to see the two candidates campaigning for the job everyone is talking about. No, not McCain and Obama, but the two candidates for the president-elect of the ACS. As the biggest scientific society in the world, this is a big job.

As I approached one of the candidates, Josef Michl, I noticed he was chattering to Bob Grubbs (see earlier post). Michl was very keen on sustainabilty. And this is a broad recurring theme of this meeting. Chemists realise the opportunites they have to help the planet. Of course, chemistry is the underpinning science to the techologies that are being investigated to replace fossil fuels. I can only imagine that in future this theme is going to engulf these meetings even more.

The other presidential-elect candidate had a very firm handshake and free colour-changing pencils. Another Joseph, from Purdue, Joseph Francisco told me about his plans to unite retired chemists and young, keen postdocs to create an ACS-centred bank of expertise. is focus was much more on the business side of chemistry, and in particular small businesses.

Two very differnent candidates with very different agendas. It will be interesting to see who wins. At the moment I wouldn't like to call it, but the trend towards sustainability gives me the feeling that Michl might just steal it.

Posted by Katharine Sanderson on August 20, 2008
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I wrote a story yesterday about a clever way to make tiny batteries using a rubber stamp and a virus. It was actually from a paper that came out in PNAS, but one of the authors, Paula Hammond is here at the meeting. She is working with Angela Belcher on some very cool viruses.

The paper outlines a simple way to build up a polyelectrolyte system, and coat a virus onto it, then let cobalt oxide nanoparticles grow on that. Stamp all this cobalt-side down on to a platinum strip, add a thin piece of lithium to the other side and hey-presto! A teeny tiny battery.

In my discussions with others about the work, it seems that people have been playing around with viruses for a while now, but we should start to see a lot more practical applications coming out of this tinkering in the next few years.

Posted by Katharine Sanderson on August 19, 2008
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Last night was the poster session. It was late, I was jet-lagged, tired and emotional, but I dutifully showed up, if only to get my free beer. As ever this was a really well-attended event. It's impossible to see everything so I decided to pick some of my favourite titles for you to muse over. They show the amazing breadth of this meeting, and some of them actually make chemistry sound, well, really interesting.**

Impact of thermal and nonthermal processing techologies on quality of apple cider (one close to my heart)

Lanthanide pyrone and pyridone complexes for the treatment of bone density disorders

Reinvigorating the chemistry curriculum with Fourier-Transform Nuclear Magnetic Resonance (FT-NMR) spectroscopy

Measurement of the contact angle of a water droplet on a flat surface

Heavy metal accumulation by common garden plants: A chemical and spectroscopic approach

** i'm not saying that chemistry isn't interesting, by the way. I love chemistry, but sometimes it is hard to persuade others not involved in the field

Posted by Katharine Sanderson on August 19, 2008
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Some people have all the bad luck. I was recommended to go this morning to a session on self-replication. Sounds cool, i thought. I bet it will be busy...

But I was very wrong. Where was everyone? The recommendation turned out to be right, and I really enjoyed Douglas Philp's talks about self-replicating systems, but the room must have had about 15 people in it. I didn't get it, so I asked Philp how come he had failed to pull in the punters. "I was up against Bob Grubbs," he said.

Ah, it all becomes clear. That's bad luck I said. Grubbs is a Nobel prize-winning chemist from Caltech who is a giant in the catalysis world. He even has his own catalyst.

Poor Doug, I thought. Still, better luck for his next talk this afternoon. Nope, it seems the Philp brand of chemistry will fail to reach the masses once more. This afternoon he is up against Barry Sharpless, also a Noble prize-winning chemist, from Scripps, who has more than one eponymous reaction.

Ouch.

The message to Doug Philp, and anyone else landed with these unfortunate timetable clashes is clear: you're going to have to get a reaction or a catalyst named ofter you. Or you're going to have to win the Nobel prize in chemistry. Preferrably both.

Better luck next year, eh?

Posted by Katharine Sanderson on August 18, 2008
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A few weeks ago I wrote a news story about some work done by Dan Nocera at MIT. He's managed to make a very simple catalyst that can generate oxygen directly from water - so helping those people trying to mimic photosynthesis and save the world's energy crisis.

At the time Nocera wasn't sure what the mechanism was for the formation of the cobalt catalyst. In today's talk he confirmed what he had thought then - that the cobalt gets oxidised all the way to its +4 oxidation state. He was also very confident in the technology he is developing. "I guarantee in under five years you'll see this," he said. Companies are coming out of the woodwork, he says, to develop a functioning, practical system.

Other big claims he made were that in a system based on his catalyst cuold produce enough fuel to run a typical house for a day in just two and a half hours. This is big talk, Dan, I look forward to it becoming reality.

Posted by Katharine Sanderson on August 18, 2008
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I had a slight deviation from the ACS yesterday while i finished up writing a story about trees that can absorb organic nitrates and turn them into amino acids. But seeing as in that single sentence I spotted at least four chemistry-relate words I thought this would be a good place to write about the research.

I shan't go into loads of details, because then you might not go and read the story (and i can't believe anyone would miss out on the chance to do that), but the news here is thus: trees, well known to gobble up inorganic nitrogen compounds, can also take up - and use, more importantly - organic nitrates that are the porducts of NOx emissions and the volatile organic compounds that trees spew out.

It's not yet clear whether this mechanism might actually help to alleviate NOx pollution, and at the same time increase photosynthesis thereby locking up more carbon. If that were the case that would be a very good news story indeed. It looks more likely that this effect is dependent on local conditions. And as the author Paul Shepson told me, even if the mechanism does help clean up the atmopshere a bit, the better solution is to stop the emissions in the first place.

Posted by Katharine Sanderson on August 18, 2008
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A number of other Nature publishing group staff are here, and are also blogging over at the chemistry blog, The Sceptical Chymist.

Between us we have more of a chance to cover a wide range of chemistry - hopefully something for everyone's taste. I recommend a read.

Posted by Katharine Sanderson on August 17, 2008
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The meeting is in full swing, and here in the city of brotherly love, beshorted chemists can be spotted all over the place. Quite a sight for the uninitiated, i can assure you.

I wandered into the ACS board meeting this morning, which also includes bigwigs from other international chemical societies today. It was an open meeting, I didn't gatecrash. I got there in time to hear a discussion about what the ACS can do to be more sustainable.

This huge meeting with 15,000 participants (and, bizarrely 25,000 hotel rooms booked), will take its toll on the city - not only because the poor Philadelphians have to play host to these many thousand scientists, but in terms of an environmental impact. Massive rooms need to be serviced, shuttle buses fuelled, conference prgrammes printed etc etc etc. This is clearly something the ACS feels bad about. Madeleine Jacobs, board member, did point out that the meeting is in some ways a hostage to the city in which it is held. But I was amused to hear talk of virtual meetings as a solution. I am sure they were talking about smaller division and board meetings, becuase I think the internet would buckle and break if it had to play host to all this chemistry all at once.

But it is an intriguing concept. Will big meetings like this become obsolete as sustainability becomes more relevant to more people?

Posted by Katharine Sanderson on August 17, 2008
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Hello everybody! Welcome to sunny Philadelphia, where I will be updating you on all the gossip from the American Chemical Society meeting.

So far i can report blue skies, hot sunshine and a summery feeling in the air. Lovely. Can I also recommend jet lag for any of you who have to get up and go to work early. Although it's not so good if you actually need to concentrate.

BREAKING NEWS:
this year, i am pleased to report that following years of disappointment, members of the press have been given drinks tickets for the poster session. That's going to save my dignity for once.

Check back for regular updates and news. Apart from the usual bumper crop of recent chemical advances It's also time to reflect, being a centennial year for the organic chemistry, physical chemsitry, agriculture and food chemistry, and industrial and engineering chemistry divisions.

Posted by Katharine Sanderson on August 17, 2008
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As the AIDS conference closes in Mexico City today, we're looking forward to the next one in Vienna in 2010 - and the shifts in the AIDS world that will hapen in the two years leading up to it.

One leadership change will happen at the end of this year, when Peter Piot, executive director of UNAIDS, steps down. Already, names of four possible candidates for Piot's job are floating around. It's also possible (but not at all certain) that Mark Dybul, the U.S. Global AIDS Coordinator, will leave his position as head of the massive U.S. foreign aid program, PEPFAR, pending the results of the November Presidetial election.

Both positions obviously carry enormous importance for the fight against AIDS. And there's been a lot of discussion at this meeting about the sort of leadership that's needed now in that fight. During the conference, I spoke to leaders in the global AIDS world to ask them what they expect the world to have accomplished by the time VIenna rolls around; you can read their answers here.

Clearly, the next two years will be critical for many reasons. We're approaching 2010 - the deadline by which everyone in the world was supposed to have access to drug treatments. Critical trials of prevention interventions are expected to report results. And there is so much work to be done in rolling out prevention measures we already know work.

Perhaps most difficult of all, there are serious political issues that need to be addressed - such as laws that prevent groups such as gay men from getting the AIDS prevention and care services they need.

The new AIDS leadership will determine whether the world meets any of these goals. Already, there's discussion and criticism about how that leadership should look. One thing is crystal clear: it must be a priority to appoint leaders who are willing to speak the truth on politically difficult subjects, such as sexual behavior and injecting drug use. Becuse all the treatment and prevention tools in the world won't do a bit of good if we're not getting them to the people who need them most.

Posted by Erika Check Hayden on August 08, 2008
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So, the ESA is coming to a close. This was my first time attending, and I was very impressed with the science. There were not, however, enough parties. Here are a couple of shots from last night’s shindig at the Milwaukee Public Museum, an old fashioned collection of skeletons, butterflies in cases, and lots of dioramas peopled with mannequins. Food was served in a little mannequin-peopled village called “The Streets of Old Milwaukee”, and the consensus was that it would not do to be there alone at night. Various food was served. I had the German platter, with potato pancakes. Yes, that picture is of an the world’s largest bowl of sour cream.

The highlight of the evening was contra dancing, a kind of complex-looking but not too hard (at least for this crowd) dancing with a caller, in which you end up dancing with everyone in the room—not a bad idea for a mixer. The program chair for this year’s meeting, Louis Gross, is apparently a contra dancer himself.

I talked with Richard Primack of Boston University, who has been using records collected by Henry David Thoreau to see if blooming times in the woods of Concord, Massachusetts have been shifted by climate change. They have, by seven days.

He thinks that the clearest trend in the Ecological Society of America is its shift, en masse, towards studying climate change. “Two years ago there were very few papers on climate change,” he said. “Four years ago there were virtually none. But if you look at this year, it is becoming the major driving topic of the ESA.”

That’s all from Milwaukee. Next year the meeting will be held in Albuquerque, New Mexico.

Posted by Emma Marris on August 08, 2008
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US military cargo ships from the Admiralty Islands brought the brown tree snake to Guam. It ate 10 forest bird species to extinction; the last two native species are clinging to life.

“What we have is an island with no birds,” says Haldre Rogers of the University of Washington in Seattle. “I found an conservationists nightmare, but an ecologist’s dream.” Rogers was able to imagine a world without birds, “the fate of a silent forest” without birds to eat bugs and disperse seeds.

Looking at seed dispersal, Rogers reckoned that seeds and seedlings would no longer be found far from their parents. And that’s what she found. Without birds to eat seeds and fly to new locations before they drop them or defecate them out, they all just fall—plop—right under their parents.

Without a sudden resurgence of avian dispersers, the landscape of Guam might change substantially, with clumps, or indeed, rings, of single species and wide-open space in between.

Photo by Isaac Chellman

Posted by Emma Marris on August 08, 2008
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Kasi Jackson of West Virginia University studies images of female scientists in horror films. But not just any horror film: “My criteria were puppets, people in rubber suits, or claymation," she says. "None of that fancy CGI stuff allowed.”

Jackson believes that B movies are actually more revealing of cultural currents than $100 million blockbusters created by marketers. In between the splatter and frontal nudity, interesting scenerios play out: women scientists as mediators between Science with a capital S and Nature with a capital N; women scientists as maternal protectors of nature—to humanity’s cost.

So I asked Jackson for her top 3 favorite B horror films featuring female scientists. And viewer beware, some of these are really gory.

1. Carnosaur (1993). Diane Ladd plays a mad scientist in a pink lab coat who decides that humanity, having trashed the planet, no longer deserves to live. After some scientific finagling, women begin giving birth to dinosaur eggs. Jackson’s fave quote from Ladd’s character: “To understand nature, you have to become as remorseless as Nature herself.”

Jackson says, “In spite of the giant dinosaurs, it is really a pretty sophisticated critique of science and society.”

2. Aligator (1980). A woman who once had a pet alligator grows up to be a zoologist played by Robin Riker. The pet alligator grows up to be mutated into gigantic proportions by a nefarious pharmaceutical company. Dismemberment ensues.

Jackson says, “In spite of the giant alligators, the woman plays a real scientist who actually does the kinds of things that scientists do.”

3. Kingdom of Spiders (1977). Tiffany Bolling plays an entomologist involved in a very serious spider situation, in which hordes of the arachnids begin mobbing cattle when pesticides kill off their more usual prey. Jackson points out that she also does something perhaps unique in the history of cinema: she resists the amorous advances of William Shatner.

Jackson says, “I really have a fondness for William Shatner, and besides, it really is a classic example off the ‘nature out of balance’ theme.”

Break out the popcorn.

Posted by Emma Marris on August 07, 2008
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Prevention is a huge theme of this AIDS conference, as it was in Toronto. Today, scientists addressed one of the uncertainties that might sandbag a promising prevention strategy.

Many scientists, advocates, public health officials hope that antiretroviral drugs, given as topical microbicide gels or as oral "Pre-Exposure Prophylaxis" (PrEP), might protect people from HIV infection. Twelve microbicides are being tested in clinical trials, and seven trials of oral pills as preventatives (a.k.a. pre-exposure prophylaxis, or PrEP) are planned or underway. Despite some early failures, many HIV experts are optimistic that ongoing trials will yield more positive results.

But one big issue looming over these trials is drug resistance. The drug regimens used in the trials aren’t designed to stop HIV from multiplying in the body – they’re only designed to keep the virus from invading in the first place. So there’s concern that people infected with HIV will develop drug resistance if they’re inadvertently placed on preventive drug regimens. That could be a problem for both HIV-infected patients and anyone else to whom they transmit a resistant virus.

Today, John Mellors of the University of Pittsburgh showed a mathematical model that describes how such resistance might evolve, and how serious a problem it could be.

Mellors’s model predicts that the amount of drug resistance in these prevention trials will depend on lots of factors, including how many people with HIV unknowingly participate in the trials. In the best case scenario, relatively few will enroll, and no serious drug resistance will arise, he said. But if many HIV-infected people end up taking the drugs - the worst case scenario – its potential benefits to a population will be nullified by the amount of drug-resistant virus unleashed on that population.

Mellors said his study yielded one take-home message: “PrEP rollout must include routine testing” – as often as once a month – to ensure the people taking it are still HIV-negative. “If we give PrEP indiscriminately to those infected, we will have much higher resistance,” Mellors declared.

And, as Mellors pointed out, regular HIV testing might be possible in the context of a clinical trial, in which study volunteers agree to be strictly monitored. But it’ll be a lot more difficult in real life, when many more people take the drugs under less controlled conditions.

The scientists running these prevention trials already know that drug resistance might be a concern, and they’re watching out for it. But Mellors’s study suggests we should already be thinking about what to do next if these trials succeed. We’ll need a plan for giving out the drugs responsibly. And given how difficult it can be to convince people to be tested for HIV even once, testing them over and over again could be challenging indeed.

It's just one more reminder of a mantra that has been repeated often at this conference: we can't count on any magic bullet to stop HIV.

Posted by Erika Check Hayden on August 07, 2008
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Jane Kavanagh of University College Cork wins a prize for most self-deprecating talk title, with “As dull as ditch water? Elevating the status of the undervalued drainage ditch”

Kavanagh studied a network of ditches draining several farms in County Cork, Ireland. As you can see from the photo to the right, which she kindly supplied, her ditches are lush and attractive. Her sampling of macro-invertebrates revealed that they also like streams in that they harbor quite a bit of diversity, with communities dependent on variables like nutrient composition and water flow.

“These are marginal habitats that are largely ignored,” says Kavabagh. “Farmers leave them alone. Nobody really cares about them. So they are fair game for us. They are significant habitats, important in overall gamma [landscape scale] diversity, and because they are so numerous, potentially important for conservation.”

This kind of space could fall under the rubric of "novel ecosystems", a really fascinating concept I mentioned briefly earlier. The idea is that humans changed and ecosystem, but are not actively managing it, so that what one might call "natural processes" are still taking place, just with a new cast of characters and a new starting state. I expect to see more and more studies like this. Keep an eye out for the succession of street corners, the food webs of football fields and the trophic cascades of cracked tarmac.

Posted by Emma Marris on August 07, 2008
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Decades after AIDS first appeared, doctors are still hoping for a cure.

This week, Tony Fauci, head of the U.S. National Institute for Allergy and Infectious Disease, added his voice to that conversation with an opinion piece on CNN and a talk at a special session on the future of AIDS.

Fauci is saying a cure may be possible - for a few people - if doctors treat them very aggressively within days after infection. Under these conditions, it will be well-night imposible for the vast majority of AIDS patients to be cured. But the conversation about a cure has a broader significance, because it brings a dose of optimism among the painful and stark realities surrounding this disease.

Still, there's a long way to go before such cures are possible, molecular biologist Robert Siliciano of the Johns Hopkins University School of Medicine in Baltimore, Maryland, told the meeting yesterday.

Siliciano said that drugs can indeed slash HIV down to almost undetectable levels in many people and called this the first step to a cure. But, he said, scientists must now tackle steps two and three by finding everywhere in the body that HIV can hide out after an individual becomes infected – the so-called “viral reservoirs” - and figuring out how to flush the virus out of those reservoirs so it can be attacked by drugs.

“It would be a mistake to say we’re one-third of the way there to finding a cure for HIV infection, because the second and third steps may prove much more difficult,” Siliciano said.

And, Siliciano added, the possiblity of a cure brings with it a responsiblity for researchers and drug companies: "What it means is that treatment failure is not inevitable," Siliicano said. "[I]f we could develop forms of these drugs that could be taken for life without unacceptable toxicity, then it is, in principle, possible to offer everyone who is currently living with HIV infection the chance for a normal life."

Posted by Erika Check Hayden on August 07, 2008
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What is the typical landscape of the United States? Jeffrey Cardille, of the University of Montreal wondered the same thing. He may be in Montreal now, but he’s from the US of A, and a big Woody Guthrie fan. Guthrie, in his alternative national anthem “This Land is Your Land” invoked the “redwood forests,” the “gulf stream waters” and so on. But could it be that the archetypal US landscape these days is rather a cornfield or a brand new subdivision?

To find out, Cardille used an algorithm called “affinity propagation”, made famous in this Science paper by Frey and Dueck. As Cardille explains, the algorithm is “a way to find representative samples in complex datasets.” In the Science paper, it was used to create clusters of faces the same people out of a sea of photographs. Each cluster was organized around a central exemplar photo.

Cardille used the same method on landscape data from the National Land Cover Data Set, and metrics extracted from the dataset with a program called fragstats. He gridded the lower 48 off into 6 km by 6 km squares and then let the algorithm rip on the data— He was only able to run 5% at a time due to computing power limitations. "We would have needed a 500 GB computer to do the whole US," says Cardille.

What emerges on any one of the runs are something like 17 exemplar squares, real chunks of the landscape that best represent the totality of the landscape. Predictably, of the 17 in the run he presented, 13 are human dominated—row crops, clear cuts, urbanizing suburban land, and the like. Two are carefully managed national parks. Just two are more or less running themselves. One of these is a square of the vast shrub-lands of Texas.

Posted by Emma Marris on August 07, 2008
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Assumptions can be dangerous, particularly when it comes to disease. And so it’s important to note that at the AIDS 2008 conference experts have challenged numerous preconceptions about HIV transmission.

One example of this involves risks relating to heterosexual sex. It’s no secret that having unsafe sex is similar to engaging in a round of Russian roulette. Scientists have often cited the estimate that one encounter of unprotected heterosexual intercourse with an infected individual carries a 1 in 500 to 1 in 1,000 chance of HIV transmission. But results presented here in Mexico City suggest that in certain circumstances the risk is much, much higher than that.

Myron Cohen of the University of North Carolina, Chapel Hill spoke here yesterday about data from a recent systematic review he helped conduct that suggests the story is far more complex. One study he and his colleagues looked at reported a rate of HIV transmission of once out of every 3.1 acts of heterosexual anal intercourse. They also found the rate was higher in cases where a partner had genital ulcers, for example, which facilitate the spread of virus.

So while the 1 in 1,000 figure might apply to some heterosexual encounters, it certainly does not apply to all of them.

Posted by Roxanne Khamsi on August 06, 2008
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Ecologists often study succession in communities. That is, after a disturbance like a fire or windstorm or, indeed, even volcanic eruption, plants and animals re-colonize the site in predictable patterns. But why wait for a fire, when you can just wash your hands or wait for a brand new leaf to emerge from a tree? Voila, a blank slate for microbes of various kinds to colonize—and quickly.

“There has been a huge amount of work on plant community succession studied from an ecological perspective,” says Noah Fierer. “And food scientists have studied how food rots, but that’s it.”

Until now. Fierer is running several different projects studying microbial succession on surfaces including new leaves, which emerge from a tree as “sterile or close to sterile” according to Fierer, and the palms of undergraduates.

In the leaf experiment, Fierer and Co. visited the same plains cottonwood tree from leaf out until leaf fall, from May until end of September to see what microbes lived on it when. “Some people had speculated that it was going to be random,” says Fierer, but he showed that it looked a lot like succession on a larger scale, with recognizable early, mid and late succession community patterns.

“We are confirming 19th century ecology,” says Fierer. “At a coarse level of resolution, microbial succession is not different from macrobial succession.”

There are hundreds of microscopic species per leaf, and the details of what they are doing there are still vague. “The next step is to figure out are the early colonizers physically different than the midstage colonizers, and why they switch,” says Fierer. “I think they are responding to changes in leaf physiology, but I’m not sure.”

If I had Fierer's tools, I would track succession on a laptop keyboard from box-opening to first anniversary, or maybe on decomposing apples in different environments: urban gutter, shady woods, bobbing in the ocean, or in my shoes...once you start thinking about it, the neat experiments to run are endless.

Posted by Emma Marris on August 06, 2008
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In recent weeks we’ve heard announcements about increases in funding towards the treatment HIV/AIDS. At the G8 summit in Hokkaido, Japan last month, world leaders set the target of spending $60 billion over the next five years towards tackling a handful of diseases, including HIV/AIDS. And just last week US President George W. Bush reauthorized an augmented version of the President's Emergency Plan for AIDS Relief (PEPFAR), which will is slated to supply $48 billion through 2013 to help fight AIDS, tuberculosis and malaria in regions such as sub-Saharan Africa.

But with increased spending comes increased scrutiny of returns on investment—and that’s very much a topic of discussion here at the AIDS 2008 meeting.

I attended a session yesterday devoted entirely to exploring how HIV/AIDS interventions can be improved through what’s known as ‘operations research’ – a field focused on using mathematics and other analytical tools to optimize systems. At the session experts stressed that efforts to combat HIV/AIDS have to do a better job of tracking the distribution and use of resources. In other words, a business-like approach to collecting data is necessary to assess the efficiency of prevention and treatment measures.

At a talk today, this message was echoed by Stefano Bertozzi of the National Institute of Public Health in Cuernavaca, Mexico. He noted that some centers devoted to HIV prevention have a poor grasp on the number of people they serve. That makes it nearly impossible to know what it’s costing to reach each individual. “Imagine if Volkswagen didn’t know how much a car cost or McDonalds didn’t know how much a hamburger cost,” Bertozzi said. “We need to be much more efficient about our delivery” of HIV/AIDS interventions, he added.

Several people I’ve spoken with here have highlighted what they see as a very promising example of how to turn things around. They point to the Avahan India AIDS Initiative, an ambitious HIV prevention program funded by the Bill & Melinda Gates Foundation. The initiative takes an aggressive approach when it comes to collecting data from their campaigns, and then reassessing what changes need to be made immediately to optimize the impact their outreach efforts. For example, in programs designed to distribute condoms among sex workers this approach might mean involving more peers within these at-risk networks to help hand out condoms, rather than relying simply on outreach workers who remain somewhat on the periphery. The bottom line is that taking a closer look at the numbers and networks of people reached in intervention programs could add up to a much more effective strategy to fight HIV/AIDS.

Posted by Roxanne Khamsi on August 05, 2008
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A food web talk examining structural characteristics of webs that predict stability was hard for me to follow. But it introduced me to the 13 food web motifs: the 13 possible interactions between three species. The speaker, Daniel B. Stouffer, came to the conclusion that persistence of isolated motifs does not predict whether they will contribute to stability in a full food web.

I was thinking, while looking at his slide with the above figure, which comes from Milo, R. et. al. Science 298 (824-827) 2002, that one could write a book with 13 short vignettes about three people and love, using the 13 food web motifs to determine the structure of the emotional webs between the three. And one could call it “The Persistence of Isolated Motifs”.

Posted by Emma Marris on August 05, 2008
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Now here’s in mage with an interesting back-story. This is a false-color infrared image, taken from an sensor called ASTER aboard the TERRA satellite, shows some a shallow lake in Iceland called Myvatn, which is well known for “periodic unbelievable eruptions of midges” according to Phil Townsend, of the Forest Remote Sensing Lab at the University of Wisconsin, Madison. The midges leave the lake en mass over a week or so, mate, and keel over on the ground.

This midge pulse delivers a huge amount of biomass to the land around the lake, and as a consequence, it is haloed by vegetation distinctly lush compared to what’s going elsewhere in the area.

In these images, brighter red indicates more vigorous vegetation. Myvatn is the paradigm case: a thin border of hot pink rings the lake, comparable in brightness to the fertilized pastures that show up as blobs further from the lake.

Townsend is using satellites to identify more midge lakes. The signal is less clear on other suspect lakes, but the last two seem to share the pattern. He’s also used the images to estimate exactly how much biomass is being hurled on Myvatn’s shore during these midge pulses. Over eight days in late July and early August, the midges deposited 135 kg of biomass per hectare per day within 150m of the shore.

Posted by Emma Marris on August 05, 2008
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Here’s the general shape of the meeting
Number of attendees: about 3,000
Number of presenters, including poster authors: 2,200
Number of days: 6
Temperature in Milwaukee: 78 °F (26°C)
Press room hospitality: RC Cola
Younger attendee uniform: button up shirt, khakis
Older attendee uniform: vaguely Hawaiian print polo in earth tones, khakis
Chic accessory: last year’s tote bag

Posted by Emma Marris on August 04, 2008
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Well, we’ll never make sense of human sex, but we might make some sense of snail sex.

Adam Kay of the University St. Thomas in presented work on Potamopyrgus antipodarum, the New Zealand Mud Snail, which comes in both sexual and asexual flavors. When considering the snails it is unclear why sex should have evolved and why it should persist. The same is true of biology more generally. There is a cost to males, who are now not guaranteed to reproduce, and asexual populations just reproduce much, much faster.

According to Kay, there are more than 20 hypothesis for why sex exists, mostly genetic, focusing on phenotypic results of recombination. But their group has got another theory that I think is quite dashing in its simplicity. Most asexual snails have not just two chromosomes, but three (a little extra buffer against deleterious mutations usually considered to be good news). Chromosomes and associated RNA are made of nucleic acid, and nucleic acid contains tons of phosphorus.

“In invertebrates, DNA and RNA can make up a large fraction of organismal dry weight,” says Kay.

I bet you can guess where this is going. The hypothesis is that in places with limited phosphorus, the snails can’t afford to have all that nucleic acid, and so sexual snails are selected for.

So far, their evidence consists of a clear pattern of asexual snails being stuffed with phosphorus and sexual snails being phosphorus lean. And there you have it. Snails have sex because they are broke.

UPDATE: Kay's collaborator, Maurine Neiman, a biologist at the University of Iowa, tells us about the cool snail image above: "The snails are not naturally colorful, but were painted to identify four different lineages in an experiment studying how diet affects their elemental composition. They are also very tiny; the grid is 1 cm x 1 cm."

Nieman also asked that I mention the undergraduates from St. Thomas who did a lot of the work and will be authors on the paper, Katherine Theisen and Madelyn Mayry.

See also Evolution: Scandal! Sex-starved and still surviving

Posted by Emma Marris on August 04, 2008
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Posted on behalf of Roxanne Khamsi, News editor of Nature Medicine

Heavy rain and traffic could not keep thousands of people from attending the opening session of the AIDS 2008 meeting here in Mexico City last night. There, in the massive auditorium, we heard rallying cries against HIV/AIDS from global leaders, including Ban Ki-moon, UN secretary general; Margaret Chan, director general of the World Health Organization (WHO); and Felipe Calderon Hinojosa, president of Mexico. The speakers remained on message, echoing the theme of this year’s conference: a call for broader and more comprehensive treatments and prevention measures under the headline ‘Universal Action Now’.
The crowd was generally responsive to each of the talks; but they saved most of their enthusiasm for one of the lesser-known presenters.

The biggest applause by far came after a speech made by Keren Dunaway-Gonzalez, a 13-year-old young lady from Honduras. Keren has seen first-hand the discrimination and difficulties faced by HIV-positive youngsters and edits a magazine, “Llavecitas”, to raise awareness about the need for a more concentrated effort to support infected children with medications and counseling as they plan for the future. Her talk served as a much-needed reminder that HIV/AIDS is not just a disease that affects individuals and requires individual action: it remains an illness that can impact entire families and therefore requires a family-based approach as well.
For me, the most provocative point in the opening session came during a speech made by Festus Mogae, the former president of Botswana. In his talk, Mogae outlined what he saw as a real and important difference between ‘human rights’ and ‘civil rights’. The first, he said, is sacrosanct and should never be compromised under any circumstances. But then he gave the example of a measles epidemic in which parents objected to vaccines for their children, yet authorities went ahead with the child vaccinations anyway. This, he said, was a rare example of when the need to protect the greater good and prevent the spread of a disease requires action that some might argue compromises civil rights. But he stressed that the vaccination did not violate human rights. The question is, of course, whether it is fair to draw this human/civil rights distinction for measles, HIV/AIDS or other infectious diseases, and if so what good it does to differentiate between the two. The words ‘slippery slope’ come to my mind.

Posted by Mark Peplow on August 04, 2008
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Posted for Emma Marris

Thomas Lovejoy of the Heinz Center, founder of the biodiversity concept, gave the opening plenary for the meeting. After a few preliminaries, he proceeded to chant a litany of environmental cataclysm, from invasive species to climate change and all its depressing effects, to disappearing frogs. At this point, I felt like bolting. I had heard this speech before, as, undoubtedly, had everyone else in the room, and I didn't feel a particular need to be driven to the hotel bar by despair. But I hung in there. Lovejoy went on to predict the future—bleak naturally, and culminating in "assemblages that are relatively hard to envision."

Funny thing was, I had just spent the whole day in a workshop on "novel ecosystems" where people talked about their research doing just that, studying the new ecosystems that spring up after human disturbance, and moving towards predicting them. It was an optimistic session, in a way, and it made me think again about Milwaukee as an ecosystem. What weird and interesting species interactions were afoot in the city?

This led me to photographer Eddee Daniel. Daniel's new book of photographs of the urban wilderness of Milwaukee came out recently, and photographs are on display at the Urban Ecology Center in Milwaukee's Riverside Park. These beautiful pictures make clear that what are sometimes called "trash landscapes" are as worthy of landscape photography as they are of scientific inquiry.

Posted by Daniel Cressey on August 04, 2008
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Posted for Emma Marris

The Ecological Society of America annual meeting begins today in Milwaukee, Wisconsin. Milwaukee is best known for beer brewing, Harley Davidson motorcycles and its rust-belt decline. I decided to skip the whole question of Milwaukee as a city and examine Milwaukee as an ecosystem. I began by joining a field trip that visited a forest and a prairie, both remnants of ecosystems that once covered the area in a fluctuating mosaic controlled by fire.

The prairie, a sea of grasses, sedges, flowers and reeds, blooms from the earth after a fire from a seed bank that contains, in the case of Chiwaukee prairie, over 400 plant species. Bison would have grazed in such places. Today, the Department of Natural Resources struggles to keep this ecosystem from growing bushy. Burning is "tricky", according to Marty Johnson of the Wisconsin Department of Natural Resources, as there are many houses adjacent to the prairie. The state is attempting to buy up these residential lots (developers named the area "Pleasant Prairie") to expand the habitat. He crew spends its time yanking out invasive species year-round. "Whatever is blooming, you deal with," he says. The prairie comes up to my shoulder in some places, and is at the moment alive with purple and yellow blooms. As I swished through the grass, I smelled wild bergamot and mountain mint.

Meanwhile, Renak-Polak Woods is a remnant of maple-beech forest, the ecosystem type that typically grew up in the absence of fire. The forest persisted because of two landowners that chose not to develop it for the pleasingly uneconomic reason that they liked it. Sugar maple and smooth-barked beech—"like an elephant's leg," according to Joy Wolf, a geographer at the University of Wisconsin Parkside—give the forest its name. Black cherry, many-trunked beech, and small herbaceous plants like bloodroot, wild ginger and red baneberry share the woods. Ephemeral ponds come and go, and we found a salamander and a number of crawfish nests to testify to their inhabitants.

These fragments are examples of what the landscape looked like when European settlers arrived. The difference, of course, is that these patches are held static in one phase—prairie or maple-beech forest—whereas the pre-settlement landscape was in reality a shifting mosaic of these and other types mediated by fires, fires often set by the Native Americans. So, in essence, these beautiful repositories of biodiversity are like fine museum pieces displaying fragments of an earlier, and perhaps more successful, land management philosophy for the Milwaukee area.

Posted by Daniel Cressey on August 04, 2008
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Is the UN Joint Programme on AIDS (UNAIDS) retreating from a global commitment to provide HIV prevention, treatment and care to everyone who needs it by 2010?

Reaching that commitment, which was agreed to by the United Nations General Assembly in 2006, was a major focus of the XVII AIDS conference as it opened today in Mexico City. Yet, to Stephen Lewis, former UN Special Envoy for HIV/AIDS in Africa, some are already preparing to back away from that goal.

Lewis, who now heads a foundation working in Africa, has gained a reputation for his outspokenness on issues related to HIV and human rights. He lived up to that reputation on Saturday night at a dinner in Mexico City hosted by the International Partnership for Microbicides.

Lewis pointed out what he saw as worrying signs in a report issued by UNAIDS the week before the conference.

In one section of the report, Lewis noted, UNAIDS spoke of universal access - but failed to mention a deadline by which the goal should be met. Other parts of the report use language that appears to back off from a firm commitment – for instance, speaking of moving as close as possible to universal access targets.

To Lewis, the report seemed to follow what he sees as a trend to push the universal access goal back to 2015 – a trend that, he says, is being led by the Group of Eight industrialized nations. This is a trend he calls “reprehensible.” Universal access may seem expensive, Lewis said, but it would be possible if rich nations delivered on their foreign aid promises.

And while Lewis acknowledged that the world is not on track to meet the 2010 goal, backing from it, he said, would be a huge mistake.

“I think that’s just wrong,” Lewis said. “You don’t concede the terrain in advance.”

Posted by Erika Check Hayden on August 04, 2008
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