Archer Fish Amplifies Muscle with Physics

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first_img(Visited 36 times, 1 visits today)FacebookTwitterPinterestSave分享0 The secret of the archer fish’s powerful spits has been discovered, and it isn’t powerful muscles.The fish that shoots bugs out of the air uses physics, a paper in PLoS ONE declared.  By letting physics amplify the momentum in the drop shot out of the water, the fish achieves six times the wallop its own muscles can attain.  Nature News posted a video of the fish and described how it works:The researchers found that the first section of the water to leave the fish’s mouth was traveling about two meters per second. But as the fish continued to expel water into the jet, the speed increased. This back-end power forced more water and momentum into the “head” of the jet. “As a result, the power that the head of the jet can deliver upon impact increases during shooting,” the authors explained in their paper.Vailati and team found that this is similar to a mechanism used by on-demand inkjet printers.  In a strange symbiosis of biomimetics, printer engineers may be able to improve their designs by studying how the fish accomplishes what they came up with independently.Nature News also quoted the authors’ evolutionary inclinations from their paper:The fish’s strategy is evolutionarily clever. “This advantage would come without the evolutionary cost for the development of highly specialized internal structures dedicated to the storing of mechanical energy,” the authors noted.See also PhysOrg and BBC News.   Source: Vailati A, Zinnato L, Cerbino R (2012) How Archer Fish Achieve a Powerful Impact: Hydrodynamic Instability of a Pulsed Jet in Toxotes jaculatrix. PLoS ONE 7(10): e47867. doi:10.1371/journal.pone.0047867.Evolution is not clever.  Evolution does not calculate the cost of development.  Evolution does not design specialized internal structures dedicated to the storing of mechanical energy.  Once again, we see evolution tacked on to a design story like some kind of vestigial organ from the 1800’s.The archer fish was one of the illustrations of design used by early films from Moody Institute of Science.  It remains a good illustration today, in fact, even more so.   There’s much more than muscle involved.  The fish has to correct for distortion at the air-water interface, have a perfect aim, calculate the height, and know the energy required to get the bug to release its strong grip on the twig.  All these things must work together for the fish to eat.  How many archer fish had to die before the right mutations came along?  Get real; get intelligent design.last_img read more


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first_imgYou can get involved with the guests featured on episode four of Play Your Part. In this episode viewers will discover how they contribute to making South Africa a better place to live by creating job opportunities and promoting entrepreneurship.Mogau Seshoene, known for her The Lazy Makoti brand, shows her culture through her culinary expertise. She also creates job opportunities for women. (Image: Melissa Javan)Brand South Africa reporterIn episode four of the Play Your Part television series, viewers learn how three people use entrepreneurship – each in a different way – to empower women and youth in South Africa. The guests are Gail Styger, Mogau Seshoene and York Zucchi.The episode, which airs on Saturday, 16 September 2017 at 18:00 on SABC 2, is hosted by Play Your Part ambassador Kabelo Mabalane. Artist and musician Mabalane is also a co-founder of the initiative, Shout for a Safer South Africa.The 26-episode Play Your Part series aims to inspire viewers to become active citizens and take part in volunteerism by profiling South Africans across the country who are doing extraordinary things to change people’s lives for the better.Learn more about episode four’s three guests and how you can get involved with them:Gail StygerGail Styger is founder of the Wot-if Trust. (Image supplied)Styger is the founder and trustee of Wot-if Trust. The organisation runs various programmes in Diepsloot, Johannesburg that work on empowering especially women and youth through skills development and entrepreneurship.Wot-if Trust also manages stakeholder engagement and consultation to channel BEE funds and guarantee points on the BEE Scorecard for contributions by corporates to the community.Its building, Father Louis Blondel Centre, is used as an open collaborative workspace where entrepreneurs, small businesses and community projects can access facilities and support services, more often than not without incurring costs.Contact details:Website: wot-if.co.zaEmail: [email protected]: @gailstyger or @WotiftrustYork ZucchiZucchi is a motivational speaker, who travels to townships to inspire entrepreneurship. (Image: Play Your Part TV series)Zucchi is the founder of Join the Equation, an initiative set up to match opportunities to businesses. It operates in 57 countries.Zucchi, who is also a motivational speaker, travels to townships to inspire entrepreneurship through talking to businesses.Contact details:Website: yzafrica.org and jointheequation.comTwitter: @YZP and find Zucchi on LinkedinMogau SeshoeneFor the past three years, Seshoene has been promoting South African culture and heritage through teaching people about traditional South African cuisine.Her company, The Lazy Makoti, employs rural and township women to host cooking classes using local food as well as to sell handcrafted, locally produced kitchen accessories.Mogau also hosts a cooking show on national television that showcases African recipes.Contact details:Website: thelazymakoti.wordpress.comTwitter: @thelazymakoti and find her on FacebookPlay Your Part is broadcast at 18:00 every Saturday on SABC 2.To get involved in playing your part in South Africa:Check out the conversation on Twitter: #GetInvolved; or,Find out about initiatives on Play Your Part here.Tell us how you Play Your Part through our social media channels:Follow us on Twitter: @PlayYourPartSA;Follow Brand South Africa on Twitter: @Brand_SA; andLike us on Facebook: Official Brand South Africa.Would you like to use this article in your publication or on your website? See Using Brand South Africa material.last_img read more


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first_imgShare Facebook Twitter Google + LinkedIn Pinterest Algae blooms in the Gulf of Mexico use up the majority of the oxygen in the water, leading to massive “dead zones” that cannot support fish or other wildlife. The culprit? Nitrate, running off agricultural fields through tile drainage systems. But nitrate is only part of the problem. Algae in freshwater lakes and ponds flourishes when exposed to a different pollutant, phosphorus, and the tiniest amount is enough to trigger a bloom.Illinois and the 11 other states that send the majority of the water to the Mississippi River set aggressive goals to reduce nitrate and phosphorus pollution in the Gulf of Mexico. To achieve those goals, large point sources of phosphorus, such as wastewater treatment plants, will need to invest in new infrastructure. But new research suggests there could be a role for farmers, as well.Laura Christianson, assistant professor of water quality in the Department of Crop Sciences at the University of Illinois, is an expert in woodchip bioreactors. She has done extensive work to demonstrate the potential of the woodchip-filled trenches in removing nitrate from tile drainage water in croplands.“The woodchips and the nitrate are necessary for the bacteria to complete their life cycles. As they consume the nitrate, it is removed from the water. It’s a biological process,” Christianson said.In a recent study, Christianson and several colleagues looked at whether they could also remove phosphorus by adding a special “P-filter” designed to trap the fertilizer-derived pollutant. The team tested two types of industrial waste products in the P-filters: acid mine drainage treatment residual (MDR) and steel slag. Phosphorous binds to elements such as iron, calcium, and aluminum contained in these products, removing it from the water.Rather than mixing MDR or steel slag with woodchips in one big nitrate- and phosphorus-removing machine, the team placed a separate P-filter upstream or downstream of a lab-scale bioreactor. They ran wastewater from an aquaculture tank through the system and measured the amount of nitrate and phosphorus at various points along the way.Nitrate removal was consistent, regardless of P-filter type and whether the P-filter was upstream or downstream of the bioreactor. But MDR was far superior as a phosphorus filter.“It removed 80 to 90% of the phosphorus at our medium flow rate,” Christianson said. “That was really, really good. Amazing.”Steel slag, on the other hand, only removed about 25 percent of the phosphorus. “But steel slag is a lot easier to find in the Midwest. And according to the Illinois Nutrient Loss Reduction Strategy, we’re only trying to remove 45% of the phosphorus we send downstream. Since agriculture is only responsible for half of that, 25% would be pretty good,” Christianson said.The system clearly shows potential, but several unknowns remain. Paired bioreactors and P-filters have yet to be tested in real-world conditions, although a handful have been installed in the United States. Perhaps more importantly, researchers don’t have a good handle on how much phosphorus is running off agricultural fields in tile drainage.last_img read more



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Massachusetts authorities are expected to execute an arrest warrant for New England Patriots tight end Aaron Hernandez  for obstruction of justice in connection with a homicide investigation, sources tell ABC News.The warrant was prepared after police discovered that the security system at Hernandez’s home, along with his cellphone, were destroyed, sources told ABC News.Police were at Hernandez’s home again Thursday with another search warrant based on evidence that Hernandez “destroyed his home security system,” an investigator close to the case told ABC News.The investigator and other law enforcement sources confirmed the security system was smashed intentionally. Hernandez’s cellphone was handed over to investigators “in pieces” by his attorneys, sources added.Police also want to know why a team of house cleaners was hired on Monday to scrub Hernandez’s mansion, sources told ABC News.“There’s a federal statute in every state that you cannot knowingly destroy evidence. And what [authorities] believe has happened here is that the home surveillance system was destroyed, the cell phone was destroyed, the house was cleaned, and the police think there was evidence that was destroyed because of that,” ESPN legal analyst Roger Cossack said.“Now the problem of course is that nobody knows what was in that home surveillance so in some ways it’s difficult for the police to make their case,” Cossack said.Surveillance video from the North Attleborough, Mass., neighborhood of Hernandez shows him with Odin Lloyd and two other people hours before Lloyd was killed earlier this week, sources confirmed to ABC News late Thursday.In addition, the Boston Globe reported that video images appear to show Hernandez and Lloyd together on Fayston Street in Boston early Monday morning.Hernandez, 23, has been at the center of the investigation since the body of Lloyd, a 27-year-old semi-pro football player, was found shot in the back of the head Monday in an industrial park near Hernandez’s home in North Attleborough.Lloyd’s uncle, Ishmael Andrew, told The Associated Press on Friday that Lloyd was dating the sister of Hernandez’s girlfriend. Family members have said Lloyd was never in trouble.Meanwhile, a lawsuit has been re-filed in Florida against Hernandez by a man the tight end allegedly shot in South Florida in February. The lawsuit contends Alexander S. Bradley was shot in the arm but the bullet traveled to his head, causing him to lose his right eye.Video footage by a WCVB-TV chopper showed Hernandez traveling by car to Gillette Stadium on Thursday morning. He left the stadium shortly after noon, then was swarmed by reporters after he stopped at a gas station.The Boston Herald reported that Hernandez was told to leave the stadium by staff, who were waiting for him when he showed up for a workout. Patriots spokesman Stacey James told the newspaper that he had no idea why Hernandez came to the stadium.“No coaches are here,” said James, who declined further comment to the Herald.Lloyd’s body was discovered in a clearing near John Dietsch Boulevard, not far from a vehicle that had been rented by Hernandez. Police have ruled Lloyd’s death a homicide.“It has been widely reported in the media that the state police have searched the home of our client, Aaron Hernandez, as part of an ongoing investigation. Out of respect for that process, neither we nor Aaron will have any comment about the substance of that investigation until it has come to a conclusion,” attorney Michael Fee said in a statement.Police are asking for the public’s help in locating a silver mirror cover believed to have been broken off a vehicle and might be visible along a route of travel between Dorchester, where Lloyd was from, and North Attleborough.The NFL is not commenting on the Hernandez situation at this point, a league official told ESPN NFL Insider Adam Schefter. But the NFL is monitoring developments, as it would in any matter of this nature.Bradley, the man who claims he was shot by Hernandez after the two argued upon leaving a Miami nightclub in February, is represented by New York attorney David Jaroslawicz.Asked whether he has a police report of the incident, Jaroslawicz declined to provide information. According to USA Today Sports, his client was in the hospital for weeks, and “I’m sure the police were there.”A spokesman for Miami-Dade police told USA Today that he was checking to see whether a report was filed.A police report from the Palm Beach County Sheriff describes a shooting incident involving a man named Bradley on Feb. 13. The sheriff’s office deemed the case inactive because Bradley refused to cooperate. Hernandez was not named in the report. read more


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New York Yankees player Alex Rodriguez says that he has come to an agreement on a “tentative” plan for him to make a comeback to the team.On Friday night, in Rodriguez’s last Double-A rehab game with Trenton, he went 1-for-2 with a home run against the Reading Fightin Phils.He will reportedly play one more game Saturday for Trenton and then return to the Yankees in Chicago on Monday, for their game against the White Sox.“I think it’s possible,” Yankees manager Joe Girardi said.Rodriguez said his return to the major league team is definite, barring an act of God.“Unless I get hit by lightning, and these days you never know,” he said.Rodriguez has missed the entire major league baseball season so far, due to a hip surgery and a Grade 1 quad strain.