|
|
Djhj How Einstein Proved the Size and Existence of Atoms
If you ;ve ever stuck your fingers together with super glue, you know pain. But imagine sticking them together with glue that bonds materials at the molecular level: that real pain. It also what scientists are doing, with the help of flesh-eating bacteria. A team of researchers from the University of Oxford has create stanley ca d a molecular glue inspired by Streptococcus pyogenes, which can cause flesh-eating diseases, reports PhysOrg. In fact, the team was interested in a single protein: one w stanley flask hich the bacterium uses to bind and invade human cells. The protein is special because it naturally reacts with itself and forms a lock, explains Dr Mark Howarth, one of the researchers. Taking that single protein as a design cue, they ;ve devel stanley us oped a molecular glue which uses the same concepts. Their new protein forms covenant bonds when it comes into contact with a partner protein. The bonds it forms are so strong that, when they tested a sample, the equipment used to measure the strength broke before the glue. As well as being incredibly strong, the technology can be used to make highly selective adhesives: the binding proteins adhere to themselves, but not to other entities. All that remains is to develop ways of incorporating the proteins into other molecular structures in order to create insanely strong, selective glues. [PhysOrg; Image: Will Fuller] moleculesScience Ulqs Linux Turns 20 Today鈥擜nd Shut Up, Yes, It Still Matters
There a long running debate among archaeologists about who the first humans to arrive in the Americas really were. There are two distinct sets of ancient tools that we stanley termosy find in North America, called the Western Stemmed and Clovis traditions. The question is, did the cultures that made Western Stemmed tools come to the Americas at the same time as the Clovis toolmakers Or did one evolve into the other Both were active at around the same time period, around 11,000 years ago, but the majority of evidence has pointed towards Western Stemmed tools arising after Clovis. A set of new radiocarbon dates, however, has pushed those dates around, and revealed two contemporary cultures rather than one changing into another. Research newly published in Science dates human occupation of a Western Stemmed site at Paisley Caves in Oregon back to 12,450 radiocarbon years ago, with the points themselves dated back to 11,340 radiocarbon years ago. The older dates are associated with huma stanley cup n coprolites fossilized poop, in case you didn ;t know , which were similar to the ones found at the same period as the stone tools. This pushes back the earliest dates of this culture some 14,000 years, to the point where it was concurrent with Clovis, or possibly even preceded it 鈥?w stanley cup nz hich has some major implications for the culture of the early Americas. Study co-author Loren Davis said in a release: These two approaches to making projectile points were really quite different, and the f |
|
扫码关注官方微信
发表于 2024-12-19 04:28:46
发表于 2024-12-19 04:30:35
