Homochirality: Computers Are Not the Real World

first_imgIf you solve a vexing problem in a computer model, you have not solved it in the real world.It’s a long-standing problem for origin of life research: how do you get the ingredients to be all of one hand?  The amino acids in proteins and the sugars in DNA are all homochiral, composed of one hand out of two otherwise-identical “isoforms” (chemicals with the same composition that differ only in shape).  Collections made outside of life tend to be random mixtures of left- and right-handed isoforms.  Unless there is a yet-undiscovered natural law that can amplify one hand over the other, a prebiotic protein or genetic molecule would have to form by chance (see online book). An article in PhysOrg explains the problem:“Imagine you’ve got a coin, and it’s perfectly made, so it’s not biased at all, and you start flipping the coin. Each time you flip it, it keeps coming up heads,” he said. “So then you say, something must be operating that’s causing this to happen . . . you get the same puzzle with these biological molecules, and that’s the problem of homochirality.”Yet this same article offers a new explanation. Three researchers at the University of Illinois came up with a new idea.  Will it work?The Illinois team wanted to develop a simpler model, one based on only the most basic properties of life: self-replication and disequilibrium. They showed that with only these minimal requirements, homochirality appears when self-replication is efficient enough.“There are other models, and they may be correct for the origin of homochirality on earth, if you can prove that those prerequisites existed during the emergence of life,” said Jafarpour. “But whether those foundations exist or not, for life that emerged anywhere in the universe, you’d expect that it would have self-replication, and our model says that’s enough to get homochirality.”They knew about the ideas of Sir Charles Frank in 1953. He proposed that one chiral molecule able to replicate itself might repress the formation of the opposite hand.The model relies on mathematical and computational techniques that were not available in Frank’s time. It takes into account the chance events involving individual molecules—which chiral self-replicator happens to find its next substrate first. The detailed statistics built into the model reveal that if self-replication is occurring efficiently enough, this incidental advantage can grow into dominance of one chirality over the other.This article’s optimism exceeds its realism.  Did they try this with actual chemicals in the lab?  Of course not.  They would have to start with what they needed to demonstrate: a chiral molecule able to make accurate copies of itself out of a soup of random ingredients.  Unless the copying process was accurate and efficient enough, errors would accumulate and all gains would be lost (“error catastrophe”).  But how probable is it to get such a replicator by chance?  That’s a high bar to overcome at the beginning.Presumably their replicator would be some RNA ribozyme able to catalyze its own replication.  To demonstrate its ability to follow this scenario, they would have to see it self-organize under plausible prebiotic conditions.  What are plausible prebiotic conditions?  That question is highly theory-laden.  Unless initial ingredients are agreed on, damaging cross-reactions prevented, pH controlled, temperature ranges monitored and oxygen excluded, nothing of interest would emerge.  If something unlikely did emerge, charges of investigator interference would be impossible to dismiss.That’s why their idea only works in the computer (and only on a computer programmed by intelligent human beings already made up of homochiral molecules).  It’s puzzling they compared their scenario with patterns in the foraging activity of ants, which are also living and made up of homochiral molecules. The challenge is to get non-living natural conditions to achieve homochirality.The only graphic in the article is a “computer simulation of the emergence of homochirality” as one hand grows over time in some kind of competition in the spatial domain.  The diagram is highly contrived and unrealistic, but it didn’t stop the author of the press release from making sweeping generalities from it:The work leads to a key conclusion: since homochirality depends only on the basic principles of life, it is expected to appear wherever life emerges, regardless of the surrounding conditions.“For me, the most exciting thing is that this mechanism shows that homochirality is really a biosignature of life, a 100% signature, and should be expected anywhere life emerges,” said Goldenfeld. “So for example, we just learned that there is a global ocean of liquid water under the ice of Enceladus … I think that looking for homochirality in the organic molecules that have been detected there would be a fantastic way to look for life there.”But it’s not a mechanism.  It’s a simulation.  Unless their simulation works in the real world, no such inference can be made, because it begs the question that real molecules can do this outside the computer.  Until it can be demonstrated that blind, unguided molecules can produce homochirality (and anything less than 100% is doomed to failure), the simulation has nothing to say about life on Earth, Enceladus, or exoplanets.There is, however, one cause now in operation that is capable of sorting otherwise identical objects by handedness.  That cause is intelligence.Speaking of Enceladus, Cassini flies by it today (Oct 14) in the first of three final encounters of the geysering moon (see NASA schedule).  On October 28, the spacecraft will make a daring plunge through one of the plumes to collect samples of the dust and vapors from an altitude of 30 miles.  Since another Enceladus mission didn’t make the final cut of NASA’s Discovery program (see Nature), these two encounters and the Dec. 19th flyby are likely to be the last opportunities for decades to gather data from this intriguing, unexpectedly active body.We get excited every time there’s a new proposal to solve the homochirality problem.  Excited, that is, for a few seconds, until we see more false optimism and cheating.  This proposal is all fluff.  Go into the chemistry lab, guys, and demonstrate your process!  You can’t walk onto a football field with an iPad, show a computerized play that wins a touchdown under contrived circumstances, and declare victory.The only value of this article (published uncritically by PhysOrg with no hard pushback questions) is that it makes a clear statement of the problem.  The problem remains as unsolved now as it was in 1953. It remains evidence of life’s uniqueness, as it was to Louis Pasteur.  The conclusion from our online book* remains: “We find that there is no lessening of confusion until one accepts the logic that ‘intelligent’ systems could not arise without an intelligent Designer.”*This book, published first in 1973, was among the first to use the term “intelligent design” explicitly. It was the author’s inference from the extreme improbability of chance to achieve the high degree of complex information seen in even the simplest conceivable living cell.(Visited 100 times, 1 visits today)FacebookTwitterPinterestSave分享0last_img read more

It’s Back! Layar’s Mobile AR Browser Relaunches On iPhone

first_imgTags:#Augmented Reality#web 12 Unique Gifts for the Hard-to-Shop-for People… Related Posts chris cameron 5 Outdoor Activities for Beating Office Burnoutcenter_img 4 Keys to a Kid-Safe App In December of last year, augmented reality (AR) browser makers Layar chose to pull its iPhone app from the App Store due to frequent crashes reported by users. They thought it was better for their brand to remove the application than to promote a faulty product. As we’ve mentioned in the past, Layar had hinted that a revamped iPhone app would be out near the end of February, and earlier this week they released just that.With the relaunch of their iPhone app, Layar rejoins acrossair, Wikitude and others now vying for elbow room in the mobile AR space. Layar boasts one of the largest collections of points-of-interest (POI) data sets and now that library is available again on the iPhone. The usual suspects can be found on Layar, such as Flickr photos, Google search, YouTube videos and Wikipedia articles, but one of the more unique layers on the app is Foursquare integration. Users can use the Layar AR viewfinder to find nearby Foursquare locations and by linking the app to their account can check in without leaving Layar. There is also a feature in each layer to view entries on a map, or in list view. The map is especially handy for Foursquare integration because Foursquare’s own app disappointingly doesn’t support a map view. An equally interesting layer to investigate is the Recovery.org layer which shows you which U.S. organizations in your area received funding (and the amount they received) from the Recovery Act.“The new Layar Reality Browser has a re-engineered engine under the hood. This new engine makes the application light, stable and very quick,” the company said on its blog. “It is ready to handle all the current layers and it is a good base to realize all of our exciting future plans.” Layar’s return to the iPhone platform comes just in time for the company’s new layer marketplace which will allow developers to charge users for their content; in other words, an App Store for mobile AR. If Subway wants to create a layer with all of their locations and charge $.99 for it’s use, they or any other company will easily be able to do that. One could assume that Layar will make use of Apple’s in-app purchase functionality on the iPhone, but it would be sad to see Layar lose a percentage of their cut on the purchases to Apple. If anything, that could raise prices on the layers themselves, but that’s a whole other argument.This could be a huge step forward for the mobile AR space. As these applications become more useful, more refined and more popular, companies will be excited to participate in providing branded content in an AR experience. Expect an announcement from Layar in the next few weeks about the launch of this exciting new platform, but in the meantime, iPhone users (3GS only) can go snag Layar’s free app (iTunes link) in the App Store. 9 Books That Make Perfect Gifts for Industry Ex…last_img read more

‘Delhi mein sarkar badal do’: Mamata Banerjee’s call at Opposition rally

first_imgKolkata Opposition rally | Live: ‘Modi govt has passed its expiry date,’ says Mamata  The BJP’s days at the Centre were numbered. “There is courtesy in politics, but the BJP does not follow it. Those who are not with BJP are called thieves,” she said.Ms. Banerjee claimed that the BJP did not give respect to many of its own senior leaders and people like Rajnath Singh, Sushma Swaraj and Nitin Gadkari were ignored in that party.“Modi and his associates are now talking of collective leadership, but if the BJP wins the Lok Sabha polls, these leaders will be ignored again,” she said.The present situation in the country was of “super Emergency”. It was worse than the one imposed by Indira Gandhi, she alleged. Trinamool Congress supremo Mamata Banerjee on Saturday came out with a call,‘Delhi mein sarkar badal do’  (change the government at the Centre) at a mega Opposition rally organised by her party. Ms. Banerjee asserted that the “expiry date” of the Modi government was over and a united Opposition would win the coming general election. She promised to work together along with other Opposition parties. Who the prime minister would be decided after polls, she said.Also Readlast_img read more

A brilliant Benzema takes Real Madrid to Copa semifinals

first_imgWith a fantastic brace during the first half at Girona, French striker Karim Benzema took Real Madrid all the way to the Copa del Rey semifinals.It’s official, Karim Benzema is currently going through one of the best moments of his career with Real Madrid and he just qualified Los Blancos to the Copa del Rey semifinals.The French striker has been completely unplayable during the start of 2019, his last two matches have been beautiful to look at as he’s been the squad’s offensive leader with goals and an everlasting source of talent regardless of the rival he confronts.The striker proved his fantastic moment from the very first ball he touched, it was evident that we were in for a treat and he would be one of this game’s main attractions.Karim did have Vinicius Junior as one of the most surprising partners that he could’ve asked for at this stage of the season, and also one of the most unexpected during a time in which everybody was already starting to repent from letting Cristiano Ronaldo leave the club.The Brazilian youngster has taken all Madridistas by surprise with his fresh football proposal, he has completely owned the left flank for Los Blancos and managed to get cozy with practically all the other offensive players in the squad.But make no mistake, tonight’s star was Karim Benzema without a doubt.FT Girona 1 Real Madrid 3. Real Madrid through to the semi finals #GironaRealMadrid #CopadelRey pic.twitter.com/QjQHqK9UW8— Football 24/7 (@foetball247) January 31, 2019The Frenchman’s personal show went through the brightest moment just a few minutes before the 30-minute mark, he was the one who started the first goal’s play and the one who finished it.The Frenchman started a combination with Lucas Vazquez on the right flank, he continued with Dani Carvajal and stood right in front of Girona’s goalkeeper to finish with a potent strike with practically nobody to block his shot.This continued the great dynamic that Benzema is going through after last weekend’s fantastic performance against Espanyol in La Liga, but the striker was only beginning his show.A few minutes before half time, he combined with Vinicius on the left flank and finished the play with a well-placed right-footer that hit the post and got in the back of the net for Real Madrid’s second goal of the evening.This made it a 6-2 aggregate as both squads went to the dressing room to rest for 15 minutes, but the match wasn’t over yet and another 45 minutes were still on the horizon.Sergio Ramos, Real MadridZidane reveals Sergio Ramos injury concern for Real Madrid Andrew Smyth – September 14, 2019 Zinedine Zidane has put Sergio Ramos’ availability for Real Madrid’s trip to Sevilla next weekend in doubt after withdrawing him against Levante.Since Benzema had already delivered, manager Santiago Solari decided to take him out early in the second half to rest for next weekend.Real Madrid are through to the semi-finals of the #CopaDelRey thanks to a double from Benzema and one from Llorente! 🔥@GironaFC 1-3 @realmadriden (3-7) pic.twitter.com/V4ANmx6kjf— LaLiga (@LaLigaEN) January 31, 2019Vinicius also left the pitch a few minutes later and he gave Gareth Bale a chance to play for over 20 minutes, the Welshman was coming out of another muscular injury and the manager wants to bring him back to rhythm slowly.Girona wasn’t leaving without doing some damage on Real Madrid’s defense, they took advantage of a defensive mistake from Los Blancos and Pedro Porro pulled one back for the Catalan club.Marcos Llorente scored the third goal for Real Madrid late in the game for the final 7-3 aggregate. But the semifinal’s ticket was pretty much decided, the first leg result was too bulky for Girona to recover from it.This result leaves the Copa del Rey semifinalists completely resolved, with Real Madrid, FC Barcelona, Valencia, and a surprising Real Betis about to have the semifinals draw on Friday.The obvious favorites to go all the way to the final at the Benito Villamarin Stadium are the two giants, but Real Betis does have a good motivation because the final will take place in their own stadium.We will bring you all the information on the semifinals as soon as the draw ends.Que semifinales nos esperan en la Copa del Rey 🤩 pic.twitter.com/agYiJck3ed— Juego Balón (@sirjuegobalon) January 31, 2019What’s your favorite possible Copa del Rey semifinal? Please share your opinion in the comment section down below.last_img read more

CES 2019 UK steps onto the global tech stage ahead of Brexit

first_img 1 “We applaud that the UK has stepped up its presence at CES in a major way, reflecting a renewed commitment to innovation and entrepreneurship,” the CTA’s senior international communications manager, Teresa Hsu, said in a statement.Speaking to multiple sources from across the UK technology industry at the show, the consensus was that Britain would’ve stepped up its game at CES regardless of Brexit, but that the looming March deadline may have accelerated matters.”There is no greater stage to do business,” Fox said in a statement.Quality vs. quantityIn large part, the increased UK presence at CES is down to Mike Short, former Telefonica vice president, who now serves as a government advisor.”When I came to CES last year as the new chief scientific advisor to the department of international trade, it was clear that our impact was rather underwhelming,” Short said in an interview. “So I said let’s go and talk about it with colleagues back in the UK, and they agreed with me that we would step up.” The number of companies has roughly trebled to over a hundred this year, he added, and next year he’d like to see the government increase its presence in the health and wellness sector at the show.In spite of the year-on-year growth of the number of British companies exhibiting at CES, the UK Pavilion is still dwarfed by that of the French, which took up around a quarter of the space in the Eureka Park startup section of the show with some of the 414 companies the country brought to CES this year.The UK Pavilion at CES 2019. Katie Collins/CNET The UK may have a smaller contingent, but some British companies have succeeded in making a big impact.First-time CES visitor Moasure won the Showstoppers LaunchIt startup competition. The company came to the show with its motion-based measuring tool, a little puck you can move from point to point instead of using a tape measure.Moasure CEO Alan Rock, who’s been developing the company’s technology for over 16 years, said he’s not sure the company would’ve been able to attend this year without government backing.”There’s absolutely no way we would have got to where we got to without the support,” he said. “It’s a very valuable prize — we couldn’t have afforded to do that as a startup.”Not all UK exhibitors supported by the government are new to the show this year. Entrepreneur Janko Mrsic-Flogel has been coming to CES on and off since 1995. He said support from the British government waned over the years but is finally looking up again.In light of Brexit, it seems the UK government is putting renewed energy into its relationship with the US, and that its bigger showing at CES this year is just one part of that. Both Short and Fox emphasized that they saw the tech industry in the US, which will be worth £400 billion (about $510 billion) this year according to the CTA, as an opportunity for Britain.”We need to get a big slice of that,” said Fox, “and frankly, whether Britain was leaving or staying in the European Union, we need to raise our act.”The UK is looking further afield too, to the countries that are booming in Asia, Short said.”We need to make sure we accept that a lot of science and technology, which leads those exports, is a global activity,” he said. “So staying involved with all sorts of countries of innovation is a good thing that we’ve historically done, and will continue to do.”CES 2019: See all of CNET’s coverage of the year’s biggest tech show.CES schedule: It’s six days of jam-packed events. Here’s what to expect. CES 2019 The companies demonstrating on the UK pavilion are truly in a league of their own. It’s firms like these that will make sure 🇬🇧 is a leader in the industries of the future #CES2019 #CES19 #CES @CES #InnovationisGREAT pic.twitter.com/Z9jSbhJZhw— Dr Liam Fox MP (@LiamFox) January 10, 2019 CES 2019 marks the year the Brits finally stepped up their game at the Las Vegas expo, after multiple years of half-hearted attendance when the country languished in the wake of tech trailblazers such as the US, China and France.Flying the flag for the UK’s tech sector at the show was the government’s Department for International Trade. The hope was to increase inward investment in the country’s tech scene, as well as boost exports and strengthen existing trading partnerships.The British Pavilion on the show floor at Eureka Park was double the size it was in 2018, and startups at the stand were all smiles thanks to reports of sales and distributor deals they’d successfully secured during the show. The oblong booth was a hive of activity and amiable conversation. And never in my life have I seen so many men in suits at a tech show.Over on the other side of the Atlantic, meanwhile, all’s not so upbeat and rosy. With the UK’s impending divorce from the EU moving closer by the day, and no deal on the horizon, there’s a distinct air of anxiety lingering over the British economy, and the tech sector is far from immune. The country’s bigger presence at an international trade show is timely, given that this a crucial moment for the UK to reinforce its links with the tech world beyond Europe.On Wednesday, ZDnet reported that investment in British tech fell last year amid widespread uncertainty over Brexit. The UK still continues to attract the most venture capital investment in Europe, but numbers are down, whereas investment in France and Germany is on the up.The UK’s automotive sector is also struggling, with Jaguar Land Rover announcing 4,500 job cuts to its 40,000-strong British workforce on Wednesday, citing uncertainty over Brexit as one of the reasons.At a CES event Monday, Liam Fox, secretary of state for international trade, declared that tech was “indispensable” to the post-Brexit prosperity of the UK.”This is our biggest representation so far at CES and is indicative of a UK with a genuinely global outlook,” Fox said.Two years ago, the CEO of the group that organizes the tech show hit out at the UK on stage at CES. The country’s lack of support for its tech companies should be a “source of embarrassment,” said Gary Shapiro, chief executive of the Consumer Technology Association.At the opening keynote presentation of this year’s show, Shapiro presented Fox with an award for the UK’s increased presence, though Fox, an outspoken proponent of leaving the EU, was heckled by the audience with cries of “Brexit.” Commentcenter_img Fox Share your voice Tech Industry Politics Tagslast_img read more

Red White and Blue Whats at Stake In Houston November Ballot

first_img Share Watch  Red, White and Blue hosts David Jones and Gary Polland in a lively discussion with Mayor Sylvester Turner around Houston’s November ballot, understanding what’s at stake with the Houston pension solution, $50 million from the $100 million disaster relief fund to help with hurricane expenses, property taxes and revenue cap back-and-forth decisions, and the latest update on long-term flood mitigation solutions.last_img