Survival of the fittest takes a hit

first_imgIf, soon, you can receive a better flu vaccine, you can thank some very fit yeast — and the eight scientists who have observed them. In a new paper in Nature, a Harvard-led team of researchers has pioneered a study that advances the field of organismic and evolutionary biology, but promises real-world results.The example of the flu vaccine illustrates the problem. With influenza, Michael Desai, professor of Organismic and Evolutionary Biology (OEB) and of physics, explained, “You need to predict what strains will be present next year or the vaccine will not be any good.“We have the sequence of all these flu strains, and we’re watching their evolution. What you should be able to do is look at how they’ve evolved in the past and be able to predict into the future what is going to win and what is going to lose. The problem is, we don’t know how to do that prediction,” he said.The questions, said Desai, in whose lab the study was conducted, were basic. “There is this swarm of mutations that are constantly happening,” he said. “How do they battle it out, and what determines who wins?”We have been taught that evolution “is slow” and involves the “survival of the fittest,” explained Alex N. Nguyen Ba, a postdoctoral fellow in Desai’s lab and one of three co-lead authors of the new study, along with Ivana Cvijović and José I. Rojas Echenique. “It turns out that molecular evolution doesn’t work that way,” said Nguyen Ba. “It’s actually much faster than how we’ve been taught. This makes evolution way more complex than what has been anticipated.”Such evolution has been posited mathematically over the last two decades. However, said Desai, previous lab experiments have not been able to prove or disprove the theory, as they have only been able to examine the process with high resolution over a short period of time or with low resolution over a long period of time. Collectively, noted Desai, the paper’s authors — who include Katherine R. Lawrence of MIT, Artur Rego-Costa of Harvard, Xianan Liu of Stanford, and Sasha F. Levy of SLAC National Accelerator Laboratory — have done both kinds of studies.This new study, however, does both.  “We can identify every single relevant beneficial mutation,” said Nguyen Ba, citing new technology that allowed the research team to follow specific genomes (or lineages) for approximately 1,000 generations.Cvijović said the research could have gone on indefinitely. “A thousand generations is about three months of growth in our conditions,” said Cvijović, who was a graduate student in Desai’s lab and is now a researcher at Princeton. “That’s enough time to see big changes happening.”The in-depth, long-term research was possible because of a technological advance in methodology that allowed what Nguyen Ba called the “re-barcoding” of DNA. Using an enzyme to place a marker, the so-called “barcode,” at a specific DNA site, the researchers were able to follow the DNA of yeast through multiple generations. By re-tagging and re-barcoding subsequent generations to record their lineage, the team could then observe how this DNA was transmitted, noting what survived, and what thrived — or came to dominate — as generations passed.What they discovered included a few surprises. According to the existing theory, the “fittest” DNA would be that which showed up most frequently in subsequent generations. However, Desai said observation showed “fluctuations” for which the theories could not account.“Mutations and genotypes that seem to have fallen behind can leapfrog and dominate,” said Cvijović.What that means, she said, will be the subject of future research. However, it implies that evolution is even more complex than previously thought. “Our experiment suggests there may be a wide range of a large number of strongly beneficial mutations,” she said. “And their benefits are both very strong and very different from one another.”last_img read more

Deloitte: About 30% of U.S. shale operators are ‘technically insolvent’

first_imgDeloitte: About 30% of U.S. shale operators are ‘technically insolvent’ FacebookTwitterLinkedInEmailPrint分享E&E News ($):After over a decade of growth, U.S. shale drillers have entered a period of “great compression” and extreme volatility that could last years as demand for oil has plummeted during the coronavirus pandemic, according to a new report from consulting and accounting firm Deloitte.Nearly one-third of U.S. shale operators are “technically insolvent” at current oil prices and may seek to be acquired or declare bankruptcy, Deloitte said in its analysis. The contraction could have a “domino effect” on the global oil and gas industry given the outsize role of U.S. shale production, said the report, which was released yesterday.Before COVID-19 hit, oil demand worldwide was already trending downward and the market had shown some instability, mostly due to concerns over climate change, said Duane Dickson, U.S. oil, gas and chemicals leader and a vice chairman at Deloitte. The global pandemic appears to have accelerated an energy transition away from the fossil fuel, he said.With the coronavirus upending global supply chains and forcing many industries into telecommuting, oil demand is not expected to return to pre-pandemic levels “anytime soon,” according to Deloitte’s report. It is unclear when people will resume driving, using ride-share services and flying as much as they did pre-pandemic, said Dickson, co-author of the report.“We see at least three to five years before a recovery of all the major markets occurs,” he said.With Deloitte estimating that about 30% of U.S. shale operators can’t break even when shale prices dip below $35 a barrel, some firms could declare bankruptcy in the next few years, Dickson said. Others could turn to consolidation.[Miranda Wilson]More ($): Pandemic drives U.S. shale into ‘great compression’ — reportlast_img read more

Yaya Toure backs Drogba’s bid for Ivorian FA Presidency

first_imgFormer Ivory Coast captain, Yaya Toure has thrown his weight behind Didier Drogba’s bid to become the country’s next Football Federation boss.Drogba’s quest to take up the role hit a snag when he was rejected by the Former Footballers Association.However, it appears that Drogba has found support in Yaya Toure, despite previous reports of tension between the two during their playing days.According to Yaya, Drogba winning the election would be the best for Ivorian football, which is why he and his brother Kolo are backing his bid.I support Didier Drogba. I want him to win this election. Seeing Didier as president of FIF would be a pleasure… Today, we want change. We are going to support, me and Kolo (Touré),” he said in an Instagram chat with former goalkeeper, Copa Barry.While Yaya Toure was optimistic of Drogba’s ability to bring change to the country’s football, he accepts that they might have to be patient as it will take a huge effort to restore Ivory Coast to its glory days.“I’m not saying he’ll succeed tomorrow or the day after tomorrow. But if he is elected he will have 4 years to help, to bring his expertise. Because I think Drogba took courses to run a Federation, to run a club,” he added.“People have to give him a chance. Today, there’s a person like Didier who knows a lot, a lot of people, who has a good address book. It can solve many issues. It’s been 10 or 12 years since we left Côte d’Ivoire, but things are still the same. Bringing Didier in is a very good thing. I want all players to support it. It is true that things have been said and that people have their opinion and everyone is free to think what they want to think. But if they want this change [they must support it].”None of the 14 members of the Former Players’ Association voted for Drogba in the recent polls, with 11 of them backing his rival, league president Sory Diabate, while three persons abstained.A member of the Association and a former national teammate of Drogba’s Didier Zokora said they rejected the former Chelsea’s star’s bid because he had consistently disrespected them, despite being the Association’s honorary President.He added that Drogba has never attended a single one of the Association’s meetings nor did he inform them of his intention to contest for the Football Federation’s Presidency.“What we are saying is that Didier Drogba, as honorary president of the Association has never been present at a single meeting. He did not even inform us of his candidacy for the presidency of Fif. It’s a huge disrespect,” Zokora is quoted as having said on Radio Jam.The results of the election, which was done via video conferencing,  sparked a massive debate in the Ivory Coast.Drogba had been the massive favourite going into the polls, particularly after experienced administrator Eugene Diomande withdrew from the race and publicly backed the former Ivorian captain.He had also been endorsed by 48 professional clubs in the country.According to Afrik Foot, Drogba will hope to have better luck when members of the Active Footballers Association, the coaches, referees and the physios also cast their votes.“I want to get more involved. I think more and more about it. I know Ivorian football, I have played in selection for years and I invested in Ivorian football lately,” Drogba recently said about his ambitions.They are vying to replace Augustin Sidy Diallo as President.Follow @EdKwakofiMore from Citi Sportslast_img read more