This is a site that anyone who has an interest in science should keep an eye on...
E.coli...( who knew??? )It is now becoming accepted wisdom that dinosaurs and birds are closely related. Fossils have been found that appear to have remnants of feathers, and the old image of scaly or leathery giant lizards is, perhaps, starting to give way to notions of brightly coloured hairy beasts with teeth. Another recent find of a particularly well preserved T Rex bone suggests the presence of medullary tissue, which is present in female birds and is involved in egg making.
All that seems to suggest the link between the two is simple then, right? Well, not if a group of palaeontologists from UNC is to be believed:
Using powerful microscopes, the team examined the skin of modern reptiles, the effects of decomposition on skin and the fossil evidence relating to alleged feather progenitors, also known as "protofeathers." They found that fossilized patterns that resemble feathers somewhat also occur in fossils known not to be closely related to birds and hence are far more likely to be skin-related tissues, Feduccia said. Much of the confusion arose from the fact that in China in the same area, two sets of fossils were found. Some of these had true feathers and were indeed birds known as "microraptors," while others did not and should not be considered birds at all.
"Collagen is a scleroprotein, the chief structural protein of the connective tissue layer of skin," he said. "Naturally, because of its low solubility in water and its organization as tough, inelastic fiber networks, we would expect it to be preserved occasionally from flayed skin during the fossilization process."
Despite the similarities between dinosaur skeletons and modern birds, there are significant differences. One such difference can be seen from looking at their hands. Dino hands have a thumb, index and middle fingers, whereas birds derive their wings from the index, middle and ring fingers. Further, the earliest bird fossils predate the hairy or furry dinos by many millions of years.
Feduccia said the publication and promotion of feathered dinosaurs by the popular press and by prestigious journals and magazines, including National Geographic, Nature and Science, have made it difficult for opposing views to get a proper hearing.
"With the advent of 'feathered dinosaurs,' we are truly witnessing the beginnings of the meltdown of the field of paleontology," he said. "Just as the discovery a four-chambered heart in a dinosaur described in 2000 in an article in Science turned out to be an artifact, feathered dinosaurs too have become part of the fantasia of this field. Much of this is part of the delusional fantasy of the world of dinosaurs, the wishful hope that one can finally study dinosaurs at the backyard bird feeder.
Time will tell if Dr Feduccia's views manage to challenge the status quo.
Cannabis...Resilin is just one of the compounds that science is looking to synthesize, mimic, or otherwise copy. Another one, of course, is spider silk which is something of a holy grail when it comes to natural compounds that humans would like to be able to manufacture because of its strength/weight ratio. Elvin's group is working on this problem as well, with an interesting twist:
The group is also trying to add a gene that makes spider silk to the modified E. coli, so that the rubber it produces is stronger than resilin itself while being just as stretchy. "People have been trying to do similar things with spider silk for a while," says Lakes, "and I think this approach could bear fruit."
I think he's probably right. Already, some efforts* have been conducted using E. coli as the machinery to produce spider silk with varying degrees of success. Making artificial spider silk would be huge money for whomever could pull it off because it's much stronger than Kevlar—whose structure, incidentally, I can still remember drawing on my organic final a few years ago. No word yet on whether organic students will be tortured with the structure of artificial spider silk when synthesizing it is finally accomplished.
http://arstechnica.com/journals/science.arsAccording to that old anti-drug TV advert, imbibing illicit substances will turn your brain into scrambled eggs. The truth, it seems, is not quite so straightforward when it comes to cannabis. Despite decades of prohibition, cannabis remains the world's favourite recreational drug after alcohol and tobacco; almost one in eight Americans has used the drug, and the figures are almost double that for New Zealand. Proponents of this smokable herb will make many claims of its powers, from suppressing nausea to providing better cloth than cotton. On the other hand, the establishment would prefer us to think of it as a gateway drug that leads to a life of ruin, misery and more junk food than is wise.
It's not only stoners who are interested in the properties of Mary Jane though. Pharmacologists have been keen to tease out the different effects of the drug for more legitimate uses. In particular, the anti-emetic properties are sought after for treating patients undergoing chemotherapy, HIV patients gravitative towards the appetite stimulation, and MS sufferers find benefit in suppression of muscle spasticity and pain. The various alkaloids present in cannabis work by activating receptors expressed in different tissues, termed CB1 and CB2. More specific drugs that only act on one or another of these receptors have been developed in an effort to gain a better understanding of the role of cannabinoids in vivo.
Which brings me to the point. This week sees publication of a paper in JCI(pdf) that looked at the effect of HU210, a CB1 receptor agonist, on neurons in the hippocampus and behaviour. Contrary to political wisdom, HU210 didn't cause damage to the nerve cells. Instead, it stimulated their proliferation (growth) both in cell culture and also following chronic administration (no pun intended) in vivo. This is a similar response to that found with anti-depressants. Seeing this similarity, the researchers at University of Saskatchewan in Saskatoon, Canada, looked at the behavioural effects of HU210 and discovered it has anxiolytic and anti-depressant properties. Whilst The Dude might have been able to tell you that, he didn't have the data in peer reviewed journals to back it up.