Monthly Archive: August 2019

Chemists claim to have solved riddle of how life began on Earth

first_img New computational approaches speed up the exploration of the universe This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only. Explore further Journal information: Nature Chemistry Scientists have debated for years the various possibilities that could have led to life evolving on Earth, and the arguments have only grown more heated in recent years as many have suggested that it did not happen here it all, instead, it was brought to us from comets or some other celestial body. Most of the recent debate has found scientists in one of three chicken-or-the-egg first camps: RNA world advocates, metabolism-first supporters and those who believe that cell membranes must have developed first. The chemists with this new effort believe they have found a way to show that all three arguments are both right and wrong—they believe they have found a way to show that everything necessary for life to evolve could have done so from just hydrogen sulfide, hydrogen cyanide and ultraviolet light and that those building blocks could have all existed at the same time—in their paper, they report that using just those three basic ingredients they were able to produce more than 50 nucleic acids—precursors to DNA and RNA molecules. They note that early meteorites carried with them ingredients that would react with nitrogen already in the atmosphere, producing a lot of hydrogen cyanide. By dissolving in water, it could have very easily come into contact with hydrogen sulfide, while being exposed to ultraviolet light from the sun. And that, they claim, would have been all that was needed to get things going.The findings by the team are sure to garner a great deal of interest in the scientific community and others will no doubt be testing and commenting on their findings. If what they claim passes muster, their work will likely be remembered as one of the great achievements of our time. © 2015 Phys.orgcenter_img More information: Common origins of RNA, protein and lipid precursors in a cyanosulfidic protometabolism, Nature Chemistry (2015) DOI: 10.1038/nchem.2202AbstractA minimal cell can be thought of as comprising informational, compartment-forming and metabolic subsystems. To imagine the abiotic assembly of such an overall system, however, places great demands on hypothetical prebiotic chemistry. The perceived differences and incompatibilities between these subsystems have led to the widely held assumption that one or other subsystem must have preceded the others. Here we experimentally investigate the validity of this assumption by examining the assembly of various biomolecular building blocks from prebiotically plausible intermediates and one-carbon feedstock molecules. We show that precursors of ribonucleotides, amino acids and lipids can all be derived by the reductive homologation of ​hydrogen cyanide and some of its derivatives, and thus that all the cellular subsystems could have arisen simultaneously through common chemistry. The key reaction steps are driven by ultraviolet light, use ​hydrogen sulfide as the reductant and can be accelerated by Cu(I)–Cu(II) photoredox cycling. Citation: Chemists claim to have solved riddle of how life began on Earth (2015, March 18) retrieved 18 August 2019 from https://phys.org/news/2015-03-chemists-riddle-life-began-earth.html Chemistry in a post-meteoritic-impact scenario. A series of post-impact environmental events are shown along with the chemistry (boxed) proposed to occur as a consequence of these events. a, Dissolution of atmospherically produced hydrogen cyanide results in the conversion of vivianite (the anoxic corrosion product of the meteoritic inclusion schreibersite) into mixed ferrocyanide salts and phosphate salts, with counter cations being provided through neutralization and ion-exchange reactions with bedrock and other meteoritic oxides and salts. b, Partial evaporation results in the deposition of the least-soluble salts over a wide area, and further evaporation deposits the most-soluble salts in smaller, lower-lying areas. c, After complete evaporation, impact or geothermal heating results in thermal metamorphosis of the evaporite layer, and the generation of feedstock precursor salts (in bold). d, Rainfall on higher ground (left) leads to rivulets or streams that flow downhill, sequentially leaching feedstocks from the thermally metamorphosed evaporite layer. Solar irradiation drives photoredox chemistry in the streams. Convergent synthesis can result when streams with different reaction histories merge (right), as illustrated here for the potential synthesis of arabinose aminooxazoline at the confluence of two streams that contained glycolaldehyde, and leached different feedstocks before merging. Credit: (c) Nature Chemistry (2015) doi:10.1038/nchem.2202 (Phys.org)—A team of chemists working at the MRC Laboratory of Molecular Biology, at Cambridge in the UK believes they have solved the mystery of how it was possible for life to begin on Earth over four billion years ago. In their paper published in the journal Nature Chemistry, the team describes how they were able to map reactions that produced two and three-carbon sugars, amino acids, ribonucleotides and glycerol—the material necessary for metabolism and for creating the building blocks of proteins and ribonucleic acid molecules and also for allowing for the creation of lipids that form cell membranes.last_img read more

Scientists readying to create first image of a black hole

first_img This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only. Explore further More information: www.eventhorizontelescope.org/ Sagittarius A*. This image was taken with NASA’s Chandra X-Ray Observatory. Credit: Public domain Astronomers poised to capture image of supermassive black hole © 2017 Phys.org Citation: Scientists readying to create first image of a black hole (2017, February 20) retrieved 18 August 2019 from https://phys.org/news/2017-02-scientists-readying-image-black-hole.html (Phys.org)—A team of researchers from around the world is getting ready to create what might be the first image of a black hole. The project is the result of collaboration between teams manning radio receivers around the world and a team at MIT that will assemble the data from the other teams and hopefully create an image. The project has been ongoing for approximately 20 years as project members have sought to piece together what has now become known as the Event Horizon Telescope (EHT). Each of the 12 participating radio receiving teams will use equipment that has been installed for the project to record data received at a frequency of 230GHz during April 5 through the 14th. The data will be recorded onto hard drives which will all be sent to MIT Haystack Observatory in Massachusetts, where a team will stitch the data together using a technique called very long baseline array interferometry—in effect, creating the illusion of a single radio telescope as large as the Earth. The black hole they will all focus on is the one believed to be at the center of the Milky Way galaxy—Sagittarius A*.A black hole cannot be photographed, of course, light cannot reflect or escape from it, thus, there would be none to capture. What the team is hoping to capture is the light that surrounds the black hole at its event horizon, just before it disappears.Sagittarius A* is approximately 26,000 light-years from Earth and is believed to have a mass approximately four million times greater than the sun—it is also believed that its event horizon is approximately 12.4 million miles across. Despite its huge size, it would still be smaller than a pin prick against our night sky, hence the need for the array of radio telescopes.The researchers believe the image that will be created will be based on a ring around a black blob, but because of the Doppler effect, it should look to us like a crescent. Processing at Haystack is expected to take many months, which means we should not expect to see an image released to the press until sometime in 2018.last_img read more

Go citrus

first_imgBright coloured citrus fruits like orange, lemon and lime can make your skin glow.Bollywood beauty and makeup expert Puja Taluja reveals how these Vitamin C rich fruits, known for their antioxidant properties, work well for your skin.Lime juice: Take a lime, squeeze it and add it to a glass of warm water with honey in it. Take a spoon and mix the contents well. Drink it every morning before breakfast. Lemon: Get glowing skin by simply rubbing a peeled lemon on your skin. But, don’t do it for long and be gentle while doing so. It shouldn’t be done longer than three minutes. Then wash it off with water. Orange: After eating the fruit, do not throw the skin. It can be used on your face. Dry the peels and grind them. Use the powder with water on your skin. This works as a natural scrub.last_img read more

Hear it out

first_imgThe BBCSSO who have been majorly involved in cultural exchange and student interactions will be touring the country and the city for the first time ever. The orchestra is formed of 65 members who shall be holding a two-hour concert in which violinist Nicola Benedetti and composer James MacMillan will also be joining. Music education expert Paul Rissman will also mark his presence in two special concerts and workshops for students on 1 April.BBC Scottish Symphony Orchestra is on a three-city tour in March and April with concerts, educational workshops and exchange between students of India and Scotland. The visit is the centrepiece of the orchestra’s activities leading up to the 2014 Commonwealth Games.Gavin Reid, director, BBC SSO said, ‘We are thrilled to be celebrating the Commonwealth Games with such an exciting and ambitious programme of events celebrating and sharing the wonderful musical culture of both Scotland and India.’last_img read more

Delhi court takes cognizance of complaint against Gaur

first_imgA court here on Thursday took cognizance of a complaint against Aam Aadmi Party (AAP) legislator Bhavna Gaur for allegedly misrepresenting facts about her educational qualifications in her election affidavits.Metropolitan Magistrate Pankaj Sharma took cognisance of a complaint filed by lawyer Samarendra Nath Verma through his counsel PS Singh against the legislator from Palam Assembly constituency.The petitioner alleged that Gaur has furnished different information about her educational qualifications in her two election affidavits filed during the Delhi Assembly elections in 2013 and 2015. In 2013, she claimed to be Class 12 pass but in the 2015 affidavit, she mentioned herself as a Delhi University graduate and holding a Bachelor of Education degree from Maharshi Dayanand University in Rohtak, the petitioner claimed.last_img read more

Why hide contracts with FB YouTube from us HC asks Centre

first_imgDelhi High Court on Wednesday asked the government why it was “hiding” the contracts it has with social media sites like Facebook and Google and not submitted them despite orders issued five months ago.“Why are you not filing them (contract)? Why are you hiding them from us? Why aren’t you placing it? What is the hesitation? Why aren’t you doing it? It’s been five months since our May 7, 2015 direction,” a bench of justices Badar Durrez Ahmed and Sanjeev Sachdeva said. Also Read – Punjab & Sind Bank cuts MCLR by up to 20 basis pointsOn May 7, the Centre had sought time to place before the court the “exact nature of the contracts which have been entered into by the Government/Government Departments with the social media sites on the internet”.Thereafter on July 30, the government had again sought more time. Today, the bench asked,”What do the contracts say? Because we have a lot to say on that.” In response to the court’s query, the government counsel said the Centre has “standard contracts” with the sites and they are “not tailor-made”. Also Read – ‘The great gold bull market has begun’To this, the bench remarked, “that is exactly what he (petitioner) wants to say”. The court’s direction and observations came while hearing a PIL filed by former BJP leader K N Govindacharya who has raised questions on the usage of social media by government departments.The court, however, directed the Centre to ensure that the contracts it has pertaining to Facebook, YouTube and Whatsapp be filed before the next date of hearing on October 28, so that the matter can be decided finally. Advocate Virag Gupta, appearing for Govindacharya, told the court during the hearing that the “central government has become the biggest marketing agent for social media sites”.Gupta also contended that as per contracts the government has with these companies, it is “transferring/surrendering” all intellectual property rights of the data being uploaded on these sites. The high court on July 30 had asked the Centre to “come out” with details of contracts it has with social media sites to ascertain whether these websites have licences to the intellectual property rights of the contents uploaded.Earlier, the court had observed it appeared that when anything was uploaded on social media sites, the websites got a licence to the intellectual property rights (IPR) of the content without paying any royalty and had asked the Centre whether it was aware of this.last_img read more