Seeds Muscle Their Way into the Soil

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first_imgA biological motor has been found, of all places, on the seeds of wild wheat.  A team of German and Israeli scientists watched wheat seeds and found they could dig themselves into the ground.  How can a dry seed, with no muscles, nerves or circulatory system, accomplish such a feat?  It all becomes clear when you look under the awning.    You’ve probably seen the long strands attached to the seeds of grasses like wheat and oats.  These are called awns.  They’re not just decorative; they are actively involved in seed dispersal.  Once the seed drops to the ground, with awns still attached, a remarkable mechanism goes into action.  As the humidity rises and falls throughout the day and night, the awns respond by bending or twisting.    How does the bending take place?  At first, it seemed surprising anything would happen, because the tissues in cross section look uniform under an electron microscope.  The authors, though, found a remarkable feature: a “huge acoustic impedance contrast” in cross section that affects the stiffness of the awn shaft from one side to the other.  In cross section, the shaft resembles the shape of a mushroom with a cap.  The cap portion had twice the Young’s modulus as the stem – a stiffness the equivalent of spruce wood.  As humidity changes, the differential stiffness causes the entire awn to bend.  By analogy, consider how a bimetal strip, like the coil in a thermostat, bends and straightens in response to temperature.  Not only that, “silica tiles stiffen the epidermis and protect the structure as it interacts with the soil.”    So let’s follow the action in the wild.  The seed, awns and all, falls to the ground.  In real time, it might look like nothing is happening.  The seed, after all, is dead; its tissues are removed from any source of nourishment or internal energy.  A time lapse movie, however, shows the seed appearing to spring back to life.  This time, it’s a robotic life exacting its energy from the air.  The alternate bending and unbending of the awns gives a kind of “muscle” to the seed, propelling it along the ground – and even into the soil!    This mechanism for seed dispersal has been known for some time.  What’s new is that the scientists found tiny silicified hairs on the outside of the awns that act like a ratchet – they force the motion to go one way.  As a result, when oriented horizontally, the seed will swim like a frog along the ground.  (They actually said this: “The movement is reversible; thus, the humidity cycle causes a periodic movement of the awns, which resembles the swimming stroke of frog legs.”)  When oriented vertically, the seed acts like a power shovel.  The awns open and close like the handles of a post hole digger.  Meanwhile, those silicified hairs latch onto the soil particles, only allowing the seed to go down, not up.  Thus, the seed works its way deeper and deeper into the soil – safely out of the reach of predators, fire and drought.  “This suggests that the dead tissue is analogous to a motor,” they said.  “Fueled by the daily humidity cycle, the awns induce the motility required for seed dispersal.”    This mechanism is optimized, they said, for the soil environment of the Fertile Crescent, where civilization first began to farm wheat thousands of years ago.  In some kinds of domesticated wheat, the awns are no longer active.  The authors speculated that the length of time since domestication has reduced the function of the awns without removing them entirely.  Because humans now provide the muscle to plow the seeds into the soil, the awns have atrophied.  Apparently “use it or lose it” applies to seed muscle as well as the animal kind.    In their summary, the authors suggested that humans might gain additional nourishment from wheat – food for thought, that is.  The passive-muscle mechanism in wheat seeds might inspire, among other things, new ways to move weed killers where needed:The understanding of this seed dispersal mechanism may help in developing new concepts in weed control.  The microscopic mechanism found to provide motility to the seed may also serve as a model in biomimetic materials research.  Indeed, a hydration-dependent bending movement was recently reported in an artificial system consisting of nano-silicon columns embedded in a hydrogel film.  From a mechanistic point of view, we have discovered a device for movement that is composed of passive elements.  Locomotion is provided by a volume containing nonoriented cellulose crystallites that shortens on drying and pulls the awn like a muscle.  The energy source for this active movement is the daily cycle of air humidity.Maybe someday artificial muscles in robotic devices will work without batteries, extracting the energy they need from the environment – all inspired by the slender filaments on the grass at your feet.1Elbaum, Zaltzman, Burgert and Fratzl, “The Role of Wheat Awns in the Seed Dispersal Unit,” Science, 11 May 2007: Vol. 316. no. 5826, pp. 884-886, DOI: 10.1126/science.1140097.A passive muscle driven by moisture in the air—amazing.  Could a lowly grass figure out that it needed both a tissue differential with the right acoustic impedance to produce bending at the correct Young’s modulus, at the same time that it needed silicified hairs to act as a ratchet?  Without both, this “frog” would swim in place and get nowhere.  And what contractor laid the silica tiles?  Silicon is not a normal part of plant tissue; it had to be guided into place by epidermal cells while the seed was growing.  The fibrils in the awns, also, need to be arranged exactly right to produce the differential impedance.  The arrangement of all the parts needs to be complete before the mechanism will work.  Think of that – then think about the additional wonder that there are more motors, ratchets and machines at work, on a much smaller scale, inside every cell of the plant.    It was nice of the authors to spare us any evolutionary just-so stories about how this all came together by chance.  Their only use of the E word was in reference to human history: “The short evolutionary time since domestication (about 10,000 years), probably allowed the complete loss of awns in several domesticated wheat lines, but not the alteration of the awn structure.”  If so, this is a case of devolution, not evolution.  They actually used the word design twice.*  Anyone believing evolution could design this mechanism needs to eat more whole wheat to provide better nourishment to the brain.    The authors provided a couple of short time-lapse video clips to illustrate the bending action, but the best way to see this is to get a copy of the wonderful Moody Video production called Journey of Life.  The filmmakers made an eye-popping time-lapse sequence of wild oat seeds, which propel themselves by a similar mechanism, but with twisting action instead of bending.  You would swear you were looking at insects crawling along the ground instead of plant seeds.  This and many other ingenious seed-dispersal mechanisms are wonderfully illustrated in this film (also recapped in Part 1 of the trilogy Wonders of God’s Creation).**    Plants may seem passive, anchored to the ground.  In their own ways, though, they get around like world travelers: crawling, climbing, boating, ballooning, launching, helicoptering, hitchhiking and hunting (e.g., Venus flytrap), surprising us each time with their built-in ingenuity.*Anecdote:  One of the authors of the paper works for the Biotechnology Department of the Tel Hai Academic College in Upper Galilee, Israel.  This is in the vicinity where a certain Teacher told some parables about wheat and sowing (e.g., Matthew 13).  He also said, “I tell you the truth, unless a kernel of wheat falls to the ground and dies, it remains only a single seed.  But if it dies, it produces many seeds.” (John 12:24).  He was speaking in reference to the results His impending death would accomplish.**Project:  This article and the Moody films suggest a science project for your junior-high or high-school student.  Many video camcorders have a time-lapse function (sometimes called interval timer).  If you already own one, you have the most expensive part of a good science project.  Look for backyard weeds and grasses with awns or other external structures; for instance, the seeds of filaree (Erodium cicurarium) work like little power drills.  Suggest a hypothesis for how the shape of the seed contributes to its dispersal.  Build a terrarium where you can control the cycles of temperature and humidity using electrical timers, and use the camcorder interval timer to record the action.  Show your video clips with your display at the science fair.  This seems like a sure way to attract the attention of the judges – and the envy of the other students.  Better still, a demonstration of biological design might kindle some thoughts about a Designer. 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first_imgA five-year-old girl, daughter of a migrant labourer, was brutally raped by unidentified men in Dasuya town in Hoshiarpur district, police said on Tuesday.The girl was admitted to the Civil Hospital, Dasuya from where she was referred to PGIMER, Chandigarh, in a critical condition after the incident on Monday night, they said.Police said the girl went missing from her house last night at about 10:30 p.m. when there was a power shutdown in the area. The family members lodged a missing report with the Dasuya police station late on Monday night. On Tuesday, a passer-by noticed the girl lying in an unconscious state near a railway track. Some blood stained clothes were also found there.The father of the girl is a migrant labourer, police said. Dr. Rajesh Bagga, Senior Medical Officer at Dasuya Civil Hospital, confirmed gang rape and said the victim suffered external as well as internal wounds. A case was registered at the Dasuya police station under relevant provisions of the POCSO Act and the IPC, police said.last_img read more


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first_imgFire hits houses in Mandaluyong City Frontrow holds fun run to raise funds for young cancer patients  Salem last broke the 10-point barrier back in Sept. 16 against La Salle when he had 12 points and the following four games saw Bulldog wingman average just 4.5 points a game.And Salem put up just 3.8 points a game during the Bulldogs’ three-match skid.“Coach (Jamike Jarin) texted me and told me to just relax, play my game, and ‘we’re here for you,’” said Salem. “It’s just within me and that I just had to relax.”ADVERTISEMENT The Bulldogs were in dire need of a win to finish the first half of the season on a positive note when Salem finally hit his stride.NU’s captain fired 21 points in the Bulldogs’ 77-70 win over University of the Philippines, and Salem couldn’t help but breathe a huge sigh of relief.FEATURED STORIESSPORTSWATCH: Drones light up sky in final leg of SEA Games torch runSPORTSSEA Games: Philippines picks up 1st win in men’s water poloSPORTSMalditas save PH from shutout View comments Read Next Photo by Tristan Tamayo/INQUIRER.netIt took almost a month for Matt Salem to get his scoring groove back, and oh did he recover just when it mattered the most.National University was in a three-game skid in the UAAP Season 80 men’s basketball tournament and slipped to a dangerous 2-4 record near the end of the first round. ADVERTISEMENT LOOK: Loisa Andalio, Ronnie Alonte unwind in Amanpulo for 3rd anniversary Nonong Araneta re-elected as PFF president Brace for potentially devastating typhoon approaching PH – NDRRMC Don’t miss out on the latest news and information. center_img For the complete collegiate sports coverage including scores, schedules and stories, visit Inquirer Varsity. Trending Articles PLAY LIST 00:50Trending Articles02:36Archers, Eagles favorites to win UAAP Season 8000:50Trending Articles01:37Protesters burn down Iran consulate in Najaf01:47Panelo casts doubts on Robredo’s drug war ‘discoveries’01:29Police teams find crossbows, bows in HK university01:35Panelo suggests discounted SEA Games tickets for students02:49Robredo: True leaders perform well despite having ‘uninspiring’ boss02:42PH underwater hockey team aims to make waves in SEA Games “It’s a learning experience for me and I’ll take these struggles I had in the first round and put it to good use,” said Salem Sunday at Mall of Asia Arena. “Those things are something you come to.”“I might have been putting too much pressure on myself and it was affecting my game.” BSP sees higher prices in November, but expects stronger peso, low rice costs to put up fight Fire hits houses in Mandaluyong City UST, FEU advance to UAAP beach volleyball semifinals MOST READ Typhoon Kammuri accelerates, gains strength en route to PH LATEST STORIESlast_img read more


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first_imgIndia and Sri Lanka were billed as the favourites for the World Cup title and both have made it to the final.A look at their performance in the pastODI Head to Head: Played: 128, Wins: India 67, Sri Lanka 50, No Result: 11.Last meeting: August 28, 2010 – Sri Lanka 299-8 (50 ov) defeated India 225 (46.5 ov) by 74 runs.World Cup Head to head: Played: 7, Wins: India 2, Sri Lanka 4 No Result: 1.World Cup Last meeting: March 23, 2007, Sri Lanka 254-6 (50 ov) defeated India 185 (43.4 ov) by 69 runs.last_img


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first_imgThe doping scandal has taken a dangerous turn. A former SAI doctor, who exposed how doping was rampant at National Institute of Sports, has been beaten up at Patiala. Dr Sajib Nandi had recently revealed to Headlines Today how the authorities at NIS Patiala were hand in glove in the doping scandal. Nandi was beaten up at the entrance of NIS Patiala and dragged out of the campus by the security guards as he was set to meet Justice Mudgal, who is probing the doping scam. Nandi told Headlines Today, “I’m filing report with the police shortly. The NIS director is a corrupt person.” Unfortunately, this is not the first time that Nandi has been attacked in his attempt to cleanse the system. Back in 2002 too, he was beaten up as he tried to expose the authorities’ role and involvement in doping at Patiala. Recently, Punjab deputy chief minister Sukhbir singh Badal has taken action on the chemist shops in Patiala selling banned drugs. While raids were conducted on the shops, the state government was getting ready to cancel licences of all those found guilty of selling banned drugs. On July 5, Headlines Today had exposed how performance enhancing drugs were openly sold over the counter at chemist shops around NIS in Patiala. The expose had come amid the dope stink involving eight athletes, including golden girl Ashwini Akkunji. Headlines Today special investigation team went shopping and found no checks in place here to control the sale of banned drugs. NIS Patiala has a tarnished history dating back to 2001, when syringes and steroid strips were found in its hostels. An inquiry was ordered into the functioning of NIS by the Sports Authority of India in 2003.  Though no action has yet been taken, the report is believed to contain proof of sustained irregularities in anti-doping procedures and a nexus between NIS authorities, federation coaches and SAI officers.advertisementlast_img read more


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first_imgZURICH (AP) — The judge and prosecutor removed from FIFA’s ethics committee in May have set up an agency to advise on integrity in sports.The new Sports Governance Unit says German judge Hans-Joachim Eckert and Swiss prosecutor Cornel Borbely will lead the Zurich-based firm.The agency says “fans and sponsors expect more and more transparency and organizational governance standards.”Eckert and Borbely were effectively fired by FIFA President Gianni Infantino at the soccer body’s congress in Bahrain.Amid reports Infantino was being investigated for possible wrongdoing, the move was seen as attacking the independence of an ethics committee that had banned several senior officials since 2012, including then-FIFA President Sepp Blatter.The new agency will “advise associations, clubs, sponsors and governments on issues in the context of good governance, integrity and compliance.”TweetPinShare0 Shareslast_img read more


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first_imgNew Delhi: After ‘testing’ the potency a backward leader in bringing the vote share of the backward community into its fold, the Bharatiya Janata Party (BJP) has again given the baton to lead the party in Bihar to a leader belonging to other backward community (OBC) by appointing three-time Lok Sabha member Sanjay Jaiswal as party’s Bihar unit president.Jaiswal, who has been winning from Paschim Champaran constituency in a row since 2009, is seen as an ideological moderate and he enjoys a non-controversial image. The appointment was made by BJP president Amit Shah. Also Read – Uddhav bats for ‘Sena CM’As per political experts, the appointment of Jaiswal may help BJP in bringing some harmony in its uneven tie-up with Nitish Kumar-led JD(U). “The recent statements of BJP leaders suggesting Kumar shift the political base from Bihar to Delhi have only brought embarrassment to the party instead of any gain. There are some senior BJP leaders who are eyeing the CM post, which they cannot ‘claim’ until Nitish Kumar is there,” the political commentator said, adding that Jaiswal has the ability to push the party’s agenda as well as safeguard the interests of the alliance partners. Also Read – Farooq demands unconditional release of all detainees in J&KAs the state is scheduled to face the assembly polls later next year, the appointment of Jaiswal is seen as a move aimed at placating backward voters. Jaiswal has replaced Nityanand Rai after the later was inducted into the Modi cabinet as a Minister of State for Home Affairs. Notably, Rai had been asked to hold the post of the state BJP president till the appointment of a new full-time chief. BJP won its 17 Lok Sabha seats in the 2019 general elections and JD(U) won 16 seats. The vote share of BJP has also increased in comparison to previous elections under the leadership of Rai. Earlier, Jaiswal’s father Madan Prasad Jaiswal, who was also a doctor, had won the Bettiah Lok Sabha seat for three-time in 1996, 1998 and 1999 polls on BJP ticket. Talking to Millennium Post over Jaiswal’s appointment, Bihar BJP spokesperson Nikhil Anand said, “After Nityanand Rai’s successful tenure as a state president, Jaiswal is the next ideologically committed, honest and dynamic new generation leader will continue to expand the party among masses as well as strengthen it at the root level.”last_img read more


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first_imgVICTORIA — Business leaders say they’re concerned the British Columbia government’s budget pays too little attention to the potential impacts of a slowing global economy and a shifting housing market.B.C. Business Council president Greg D’Avignon says finance Minister Carole James is banking on robust economic growth to fund long-term social and environment programs amounting to $2 billion over the next three years.He says the council, which represents many of the largest employers in the province, credits the government for the initiatives that support families and environment programs, but the government is taking business for granted in a darkening economy. Real estate developer Jason Turcotte says the government depends on tax revenue from home sales to help fund its programs, but the budget hinders new property developments which create that wealth.James says B.C. is forecast to lead Canada in economic growth for the next two years and her budget has set aside more than $2.6 billion in contingency and allowance funds in the event of a downturn.Opposition Liberal Leader Andrew Wilkinson says the budget does nothing to stimulate the economy. The Canadian Presslast_img read more


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Junior outside hitter Michael Henchy (6) prepares to strike the ball during a match against Saint Francis Feb. 9 at St. John Arena. OSU won, 3-1.Credit: Shelby Lum / Photo editorThe team that ended the Ohio State men’s volleyball team 2012-13 campaign could be the one who the Buckeyes get their season back on track against.The No. 14 Buckeyes (5-6, 2-2) are set to host Grand Canyon as they continue their five-match homestand at St. John Arena. The Antelopes (6-7) defeated OSU, 3-2, in a Men’s Intercollegiate Volleyball Association Quarterfinal match that ended its season. A chance at revenge lies with the Buckeyes, with two matches against the Antelopes slated to start at 7 p.m. Friday and Saturday.“They’re a strong team with a lot of returners so I expect them to play really well together,” junior outside hitter Michael Henchy said. “Last time we played them, we lost in five sets and no one has forgotten that. It’s going to be a fun match to play in.”In the last meeting between the two teams, OSU led 2-1 after three sets, but Grand Canyon stormed back to win the final two and take the match.“They came out with a lot of fire and played like they had nothing to lose and ended up beating us. Everyone was in shock at the outcome of the game and it was because we took them very lightly. We can’t let that happen again,” senior middle blocker Jonathan Newton said.OSU is preparing to start off strong against Grand Canyon and hopefully take early control of the match. Newton said the Buckeyes can’t underestimate Grand Canyon like they did previously.“They are going to come out and put up a good fight. If we let them get an early jump on us then we could be in trouble. We will be able to control the game if we stop their momentum from the beginning,” Newton said.After taking some time to get some rest away from the gym this past Sunday and Monday, Newton said the Buckeyes have been working on themselves this week, instead of worrying about what the other team is going to bring to the court.“This game has a lot to do with how Ohio State plays. If we can focus on our side of the net and bring a lot of energy, then it’s going to be hard for any team to beat us in our home gym,” Newton said.OSU coach Pete Hanson said the Buckeyes will do what they can to prevent a repeat of last season’s tournament loss.“We have continued to become better as a unit and not to mention, our returning guys have a little bit of an edge to them, because of what happened last year in the playoffs. We are ready to send the message that it is not going to happen again, especially in St. John Arena,” Hanson said. read more


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Ohio State senior forward Sammy Edwards surveys the field during the second half of the Buckeyes’ 7-0 win against Illinois at Jesse Owens Memorial Stadium on Sept. 14. Credit: Colin Hass-Hill | Sports EditorThe No. 15 Ohio State women’s soccer team (11-2-1, 6-1-0 Big Ten) extended its unbeaten streak to five games with a 1-0 win over Michigan (5-4-6, 2-3-3 Big Ten) Sunday at Jesse Owens Memorial Stadium. Senior forward Sammy Edwards led the way for the Buckeyes with five shots and a goal. The Buckeyes had their breakthrough in the 81st minute as senior forward Eleanor Gabriel tore down the right side of the field and crossed the ball in through the penalty area to a streaking Edwards, where the ball was one timed into the back of the net, the lone goal of the game.The rivalry with Michigan delivered another intense game, as physical play dominated the matchup and it was clear neither team would allow any easy goals. “Just knowing it’s Michigan I think everyone is a little more hype,” Edwards said. “I definitely come into this game very pumped up and I know it’s across the board.”Ohio State outshot Michigan 17-4, and Kerr needed to make only one save. The shutout marks Ohio State’s fifth consecutive clean sheet, the longest streak since 2012. The first half provided a slow, tactical pace from both teams, neither giving the other strong chances at the goal. Most of the half was played around the midfield area as both teams battled back and forth with strong defensive plays. “It’s definitely a mental battle,” Edwards said. “A win on a Sunday can be hard. We sometimes come out slow just from having dead legs but instead of coming out slow we came out fast and set the tone for the game.”Possession favored the Buckeyes in the first half, but both teams spent most of the half measuring the defensive style of the other. Ohio State outshot the Wolverines 6-1, despite neither team finding any strong offensive footing. Michigan’s only shot in the first half came close to finding the back of the net as midfielder Sara Stratigakis sliced into the penalty area and fired a strong shot on goal, which was saved by Ohio State goalkeeper Devon Kerr. The best chance of the half for the Buckeyes came in the 33rd minute on a corner from midfielder Nikki Walts. The ball slipped out of the pack of players to Edwards, who connected with a shot that sailed just above the crossbar. The second half began with a much more frantic pace, with Ohio State leading several quick offensive attacks, which resulted in three shots.Michigan’s best opportunity of the half came on a loose ball play in the 61st minute as a defensive error led to an open lane for midfielder Katie Foug, whose close-range shot flew just over the goal. The Buckeyes had a prime chance to score in the 74th minute as a grounded cross rolled through the box to Edwards, whose shot hit the left post. Michigan goalkeeper Sarah Jackson dove for the ball and missed as it rebounded off the post right on the goal line, but all Ohio State players could do was watch as the ball was cleared by a Michigan defender. “We rely on each other,” Edwards said. “You turn to your teammates and realize that you’re not the only tired one, and you’re not alone when you hit the post. We just look to each other when someone messes up, and I think that contributes to our success a lot.”Ohio State maintained an aggressive play style for the rest of the game, not letting Michigan create many attacks and pelting the Michigan keeper with more shots. Michigan continued trying to apply pressure and equalize, but the patient attack and rigid defense of Ohio State proved too much for the Wolverines. Ohio State’s next game is Thursday against Big Ten opponent Maryland. read more