David Bradley – Page 330

Naked podcast

The ‘Naked Scientists’ – as featured on Sciencebase – perhaps don’t deserve the alarming image their name inspires. This radio show and podcast aims to strip science down to its bare essentials and promote it to the general public, says main man Dr Chris Smith, the main aim is to “help people enjoy science as much as we do and, at the same time, to have fun,” he says.

Naked Scientists is produced at the University of Cambridge and broadcast by the BBC, and recently reached 2 million podcast downloads in the last 12 months. On top of that, the show, receives 50,000 downloads per week and has been nominated by its listeners for ‘best science show’ in the 2006 international ‘Podcast Awards’.

Each hour-long edition of the programme sees the presenters encouraging the audience to experiment in their kitchens alongside the radio show and then call in with their results. So far the series has seen listeners build home-made submarines, recreate the sound of Big Ben inside their heads, and simulate an explosion in a custard factory.

Smith, a lecturer at Cambridge, started the programme in 1999 as “ScienceWorld” and in just 7 years has made grown it into a weekly local radio show to become a national and international presence with inputs to network radio across Australia (ABC Radio National) and the UK (BBC Radio Five Live). On the Internet, its companion website www.thenakedscientists.com receives over one and a half million hits per week.

Check out the latest naked science on Sciencebase. Sciencebase now produces its very own podcast – the Geordie Boffin Podcast – an irregular and irreverent look at science from David Bradley.

Bird flu drugs

In the latest issue of The Alchemist on ChemWeb.com I provide a round-up of the week’s chemistry news, of particular importance could be news that UK and Australian researchers may have found a new way to approach drug design for bird flu viruses that precludes drug resistance.

A new drug to fight bird flu that should be able to side-step the emergence of viral resistance is being developed by Andrew Watts of the University of Bath, UK and Jennifer McKimm-Breschkin of CSIRO Australia. Both Tamiflu and Relenza, the two drugs currently being stockpiled by governments in preparation for a global outbreak of bird flu, are inherently susceptible to resistance because of the way they work. Although the new drug acts on the same target as these treatments, the enzyme neuraminidase, it targets a specific region of the enzyme that essential to its function. If this region mutates the virus would no longer be viable, so that resistance cannot emerge.

Read about this and more in this week’s Alchemist.

I should cocoa

Flavanols in cocoa could stave off cardiovascular disease, something that affects almost 78 million baby-boomers in the US alone, according to a paper in the August issue of the Journal of Hypertension.

Researchers at Harvard Medical School and the Brigham and Women’s Hospital in Boston discovered that drinking a standardized flavanol-rich cocoa beverage improved several measures of blood vessel function, especially among older study participants. So, that relaxing chocolate drink at bed-time could be doing a lot of good. Flavanols purportedly improve blood flow and reduce damaging clot formation.

Interestingly, the research was sponsored by chocolate manufacturer Mars.

Read into that what you will.

Lithium

It’s not something Nirvana mentioned in their elemental song, I presume they had other things on their mind, but there isn’t enough lithium in the universe. It’s not that there’s a shortage, it’s just that our knowledge of cosmic and stellar chemistry would suggest that there ought to be more of this alkali metal than there actually is. A paper published in this week’s Nature could offer an explanation.

The problem is that old stars, which ought to be made from a mixture of elements close to the ‘primordial’ blend generated in the Big Bang, don’t appear to have as much lithium as this would require. Although most of the matter produced by the Big Bang was hydrogen and helium, theories of element production predict that there should also be a fair proportion of lithium. But the amount predicted is a factor of two or three times larger than that seen in old stars. This implies that our understanding of the physics either of the Big Bang or of stars – or both – is lacking.

Andreas Korn and colleagues look at 18 stars in a cluster of old stars to see how the elemental content of their atmospheres changes with evolutionary stage. They find that various elemental abundances depend on a star’s temperature. This, the researchers say, is because heavy elements tend to diffuse deep into the star. For those stars that have evolved into giants, the elements are mixed back into the stellar atmosphere by convection, so that the stars’ composition is restored. Not so for lithium: it does not survive the trip through the stellar interior, as it is burnt when temperatures exceed 2 million degrees.

Korn and colleagues estimate that the original lithium abundance in these stars was around 78 percent higher than that suggested by current average values – which is enough to make up the discrepancy with the predicted primordial abundance.

Nature, 2006, 657-659

Search engine bias

Search engines are not biased toward popular and highly linked websites, researchers report, in this week’s PNAS.

The internet is enormous, vast, gigantic, big and complex, search engines have taken on an increased role in guiding users to their destinations (community forums and blogs aside). But there are concerns that search engines, by means of their subjective ranking algorithms, could be creating positive feedback loops wherein popular sites that receive the most hits become more popular and so on. Eventually, this cycle shouldresult in a small subset of websites monopolizing a majority of traffic.

However, according to Santo Fortunato, Alessandro Flammini, Filippo Menczer, and Alessandro Vespignani this doesn’t actually happen. They collected data from various search engines and found that the popularity bias of search engines was weak. Search engines were found to direct less traffic to popular websites compared with a scenario where there were no search engines and all traffic was generated by web surfing.

The key reason for this apparent lack in search engine bias, the researchers note, is the wide diversity and specificity of information sought by internet users, which mitigates the ranking bias of the engine and creates balanced results. “We reconcile theoretical arguments with empirical evidence showing that the combination of retrieval by search engines and search behavior by users mitigates the attraction of popular pages, directing more traffic toward less popular sites, even in comparison to what would be expected from users randomly surfing the Web,” says the team.

So, where does this leave those seeking to tweak their position in the SERPs (search engine results pages) through SEO (search engine optimization) techniques? Your answers are most welcome…

You can read the preprint paper here and at PNAS (once it’s published) here

Solid liquid separation

Here’s a news item to make you flush with excitement, or at the very least, make your toes curl. According to a forthcoming report in the ACS journal Environmental Science & Technology, the Swiss are getting in a lather about a new “NoMix” toilet that does what all good chemists have been able to do for generations – separate their solids from their liquids. The new loo is an environmentally improved approach to spending a penny and could substantially reduce pollution problems and conserve water and energy, say the study’s authors.

The NoMix toilet collects urine separately from, ahem, solid matter. Although urine represents only 1% of domestic wastewater, it typically contains 80 percent of the nitrogen and 50% of the phosphorus in sewage.

Judit Lienert and Tove Larsen checked public attitudes toward NoMix toilets in surveys done at a Swiss school and a Swiss research institute. They found high acceptance of the toilet, with large majorities of people expressing favourable attitudes toward the toilet. That was true even though one version of the device requires men to sit to urinate.

The researchers cite the importance of involving users in the introduction of new environmental technology, especially technology that requires the kind of behavioral changes essential with NoMix toilets.

Sit a spell and read the full paper here.

Chemical Structure of Avenacoside B

Polish student Marcin Mielecki emailed to ask where he might find a 3D, as opposed to 2D, structure for the compound Avenacoside B. A very quick Google brought me almost immediately to this page (by searching for “avenacoside b mol file”: http://www.genome.jp/dbget-bin/www_bget?cpd+C08888, which provides the flat molecular structure and a link to the MDL mol file for this molecule. If Marcin has Chime or another mol reader installed in his browser clicking that link will spawn the 3D structure he requires. It’s also in Pubchem of course.

Marcin’s research focuses on the biological role of the avenacosides, which are steroidal saponins from Avena sativa.

A hearty approach to female sexual dysfunction

Heart drugs are proving rather useful to pharma companies hoping to find lucrative treatments of another kind of disorder, that maybe involves the heart, but mostly involves the loins.

A heart drug that went into clinical trials in the 1990s has become the linchpin for efforts to develop a medication to treat female sexual arousal disorder (FSAD), researchers are reporting. An estimated 40 percent of women have FSAD or another form of female sexual dysfunction, the difficulty or inability to find satisfaction in sexual expression.

Compounds that sustain the activity of vasoactive intestinal peptide (VIP) are a major target of drug research efforts. VIP controls blood flow to the vagina, and decreased blood flow is believed to be one factor in female sexual dysfunction. VIP is degraded in the body by several enzymes, including an enzyme called NEP. Blocking NEP thus allows VIP to continue working.

David Pryde and colleagues at Pfizer in the UK (the company that brought us Viagra) began work with Candoxatril, a powerful NEP inhibitor tested in the 1990s for chronic heart failure. By re-engineering Candoxatril’s molecular structure, they developed a compound with the key actions needed for an FSAD drug.

The new compound blocks NEP, takes effect rapidly, and continues having an effect for a relatively short time. “The compound demonstrates excellent efficacy in a rabbit model of sexual arousal and was expected to be similarly efficacious in humans,” the researchers state in the Journal of Medicinal Chemistry. The compound is undergoing clinical evaluation as a potential treatment for FSAD.

Punched while drunk

It’s usually fairly easy to justify even the most esoteric of scientific research in terms of improving our fundamental understanding of the universe etc etc. But, when a press release pops up announcing that drinking [alcohol] can be dangerous and that “People who drink alcohol are up to four times more likely than non-drinkers to be hurt from physical injuries such as a fall or punch…” you begin to wonder about your convictions. Apparently, this astounding discovery was made by researchers at the University of Queensland, Australia, who found that, “any alcohol consumption quadrupled the risk of injury for the first six hours after drinking alcohol and this risk remained at 2.5 times that of a non drinker for the next 24 hours.”

Do you have to have had a drink to be punched, I guess the inhibition inhibiting effects of alcohol can make some people say more provocative things that might offend someone and land them in a fight, but what about someone having a few “tinnies” alone in an armchair watching Aussie soap opera Neighbours or listening to Kylie? Are they more likely to suffer an injury or more weirdly get punched.

Some people might say that if they’re really watching Neighbours or listening to Kylie they deserve all they get, but Kerianne Watt earned her PhD for also discovering that, “people who sustained serious injuries were more likely to have consumed beer and have been drinking in a licensed premises” and “Binge drinkers were more at risk of being injured than regular drinkers”.

“My findings suggest that it’s not a property of the beverage that increases aggression and risk of injury, it’s more a personality characteristic that is attracted to a certain type of alcohol,” Watt says.

I suppose the research can be justified in terms of understanding the nature of alcohol abuse and how it relates to injury rates and it probably is quite useful to know what kinds of drink are most associated with injury, but strewth this still feels like this should have been published in the Australian Journal of the Bleedin Obvious (Aus J Bleed Obv), don’t you think?

You can read the complete press release here.

No plaice like home

The slime that covers the flat-fish plaice contains an antimicrobial agent that kills Staphylococcus aureus, the bacteria causing concern in hospitals across the globe as its drug-resistant strains spread.

Chemical engineer Trude Tvete of Nord-Trondelag University College (HiNT) in Norway, has developed a technique for extracting the antimicrobial protein from plaice slime and has tested its biological activity against several types of bacteria. “Previous research has shown that plaice slime kills bacteria, but it didn’t show which substance breaks the bacteria,” says Tvete. “I found that there is a protein in the slime that has the greatest effect.”

Read on…