Spartans boys down Chico for league win

first_imgRed Bluff >> Valentin Ramirez put up nine points in the opening period for the Spartans Friday night en route to a 61-54 league win over Chico in Red Bluff.After a strong start from Ramirez and teammate Brayden Hutchens, who had seven in the first and four 3s on the night, it was anybody’s game deep into the final frame. The Spartans scored the first 10 points before the Panthers started hitting shots. After one it was 21-12 Red Bluff. The second was a different story.The Panthers went on a …last_img read more

Few Mutational Pathways Lead to Darwinian Evolution

first_imgMutations may not be as helpful for neo-Darwinian evolution as expected, say researchers from Harvard.  Let’s say five mutations need to occur for a bacterium to gain resistance to an antibiotic, and there are 120 ways to get these mutations.  They found that only about 10 of the pathways could be selected by natural selection.  Since natural selection would have to confer better fitness at each step, most of the pathways are dead ends.    Although the team studied only one particular kind of resistance, “this finding likely applies to most protein evolution,” they said.  “Although many mutational paths lead to favored variants, only a very small fraction are likely to result in continuously improved fitness and therefore be relevant to the process of natural selection.”    See also Science Daily, EurekAlert.  The original paper was published in Science.1  The abstract states:Five point mutations in a particular beta-lactamase allele jointly increase bacterial resistance to a clinically important antibiotic by a factor of 100,000.  In principle, evolution to this high-resistance beta-lactamase might follow any of the 120 mutational trajectories linking these alleles.  However, we demonstrate that 102 trajectories are inaccessible to Darwinian selection and that many of the remaining trajectories have negligible probabilities of realization, because four of these five mutations fail to increase drug resistance in some combinations.  Pervasive biophysical pleiotropy [i.e., one modification causing a cascade of effects] within the beta-lactamase seems to be responsible, and because such pleiotropy appears to be a general property of missense mutations, we conclude that much protein evolution will be similarly constrained.  This implies that the protein tape of life [sic] may be largely reproducible and even predictable.   (Emphasis added in all quotes.)The last sentence about what this implies is purely a speculation.  They elaborate slightly in the last sentence of the paper: “It now appears that intramolecular interactions render many mutational trajectories selectively inaccessible, which implies that replaying the protein tape of life might be surprisingly repetitive.  It remains to be seen whether intermolecular interactions similarly constrain Darwinian evolution at larger scales of biological organization.”  If those larger scales are random and require multiple steps, it would seem the same principle applies.1Weinreich et al., “Darwinian Evolution Can Follow Only Very Few Mutational Paths to Fitter Proteins,” Science, 7 April 2006: Vol. 312. no. 5770, pp. 111-114, DOI: 10.1126/science.1123539.It wasn’t going to work anyway, so this just makes it harder.  They are’t talking about adding new genetic information or function, but rather losing function (susceptibility to the antiobiotic) in such a manner that each stage doesn’t kill all of the organisms in one fell swoop.  If this principle applies, as they suggested, to larger scales of biological organization, then the neo-Darwinian gig is, for all practical purposes, over.  Try getting a whale from a cow against these kinds of constraints.  This makes “the protein tape of life” predictable?  In whose Tinker Bell tale?(Visited 13 times, 1 visits today)FacebookTwitterPinterestSave分享0last_img read more

India Today @ the Olympics: Welcome to London, but keep your wallets handy!

first_imgHaving heard horror stories about the preparedness of the Heathrow airport to handle huge passenger traffic, I moved towards the immigration officer with trepidation.No doubt, the lady officer behind the immigration counter was curt and wanted to clear me quickly, but she had to fully satisfy herself that the finger-print matching was done properly. These days, with the clock ticking away fast for the opening ceremony on July 27, nothing can be left to chance if you are entering London.Past immigration, getting the media accreditation card was also not a problem at all. It really came as a surprise how all this was happening so smoothly as athletes had complained they had to face long waits.But the bigger surprise was how the transportation by tube, or the Heathrow Express, into Paddington in central London was even more efficient. The fear of getting lost by official cabs was not there and in less than half an hour, five Indian mediapersons were in central London. The surprise did not end there as shared cabs were there for onward travel from central London to Stratford, where the Olympic Park is situated.Cabbies the world over like to talk. Mike, as the 64-year-old wanted to be called, was no different. Once he got talking, it was hard to stop him.He spoke of everything — recession, high prices of tickets for the London Olympics, how Stratford was a dirty area and now had been transformed.But his anger was aimed towards the London organisers (LOCOG) as he felt the tickets were overpriced. “It’s just too much paying 150 pounds per ticket for athletics and I have been told I will be allowed inside the arena for just three hours. Imagine, I spend 1,000 pounds for the family and it seems like a waste,” Mike thundered.advertisementThe mood all over London, where the pound sterling is such a strong currency, is similar. The commoner does feel tickets have been overpriced and of the million tickets up for sale, many have disappeared!That’s a story very similar to our own Commonwealth Games, where the organising committee first printed lesser number of tickets, which resulted in empty stands.Our cabbie Mike then went on to thank us for bringing sunny weather to London. After heavy showers for weeks, bright sunshine saw Londoners strip their woolens and dress lightly. He was again cautious when he said, “Don’t be fooled, one can never say when it will again start raining.”Finally, when I reached Stratford, the virtual Olympic hub in east London, I got a glimpse of the Olympic Stadium. Security was tight and like the Delhi cops, they were shooing us away from vantage points, minus the abuses.Stratford in itself is a sleepy suburb. A new shopping complex and plenty of commercial malls have come up in a big way, but the crowds aren’t huge really. Locals who live closer to the Olympic venues aren’t the ones who will be filling in the arenas as tickets are priced high and had to be booked in advance.Inside the high security Olympic Stadium complex, which also houses the international broadcast centre and the main press centre, the final coat of paint is being applied. There is a busy look and security is very tight. From wallets to cell phones, cameras and even wrist watches, everything is put through the scanner.Yes, the security personnel are courteous, but they do look worried as the crowds have started trooping in. Food outlets are getting ready and junk food stalls are bound to do good business.However, the worrying factor is a high price one has to pay for communication. Unlike New Delhi’s Commonwealth Games, where the data cards were free, here there’s a 180 pound sterling charge, which comes to almost Rs 16,000 for the entire fortnight.If you want to extend your stay for the Paralympics, it costs a bigger bomb. Welcome to London!last_img read more