CLIQUE
Showing posts with label Current Affairs. Show all posts
Showing posts with label Current Affairs. Show all posts
Glowing Blue Waves Explained
Sea of Stars
Photograph by Doug Perrine, Alamy
Pinpricks of light on the shore seem to mirror stars above in an undated picture taken on Vaadhoo Island in the Maldives.
The biological light, or bioluminescence, in the waves is the product of marine microbes called phytoplankton—and now scientists think they know how some of these life-forms create their brilliant blue glow.
Various species of phytoplankton are known to bioluminesce, and their lights can be seen in oceans all around the world, said marine biologist and bioluminescence expert Woodland Hastings of Harvard University. (Also see"Glowing Sea Beasts: Photos Shed Light on Bioluminescence.")
"I've been across the Atlantic and Pacific, and I've never seen a spot that wasn't bioluminescent or a night that [bioluminescence] couldn't be seen," Hastings said.
The most common type of marine bioluminescence is generated by phytoplankton known as dinoflagellates. A recent study co-authored by Hastings has for the first time identified a special channel in the dinoflagellate cell membrane that responds to electrical signals—offering a potential mechanism for how the algae create their unique illumination.
James Cameron Now at Ocean's Deepest Point
A shipboard crane lowers Cameron's sub into the Pacific around 2 a.m. Monday, local time.
Photograph by Mark Thiessen, National Geographic
Cameron lowers himself into the sub for the Challenger Deep mission. Photograph by Mark Thiessen, National Geographic.
As of 5:52 p.m. ET Sunday (7:52 a.m. Monday, local time), James Cameron has arrived at theMariana Trench's Challenger Deep, members of the National Geographic expedition haveconfirmed.
His depth on arrival: 35,756 feet (10,898 meters)—a figure unattainable anywhere else in the ocean.
Reaching bottom, the National Geographic explorer and filmmaker typed out welcome words for the cheering support crew waiting at the surface: "All systems OK."
Folded into a sub cockpit as cramped as any Apollo capsule, the National Geographic explorer and filmmaker is now investigating a seascape more alien to humans than the moon. Cameron is only the third person to reach this Pacific Ocean valley southwest of Guam (map)—and the only one to do so solo.
Hovering in what he's called a vertical torpedo, Cameron is likely collecting data, specimens, and imagery unthinkable in 1960, when the only other explorers to reach Challenger Deep returned after seeing little more than the silt stirred up by their bathyscaphe.
After as long as six hours in the trench, Cameron—best known for creating fictional worlds on film (Avatar, Titanic, The Abyss)—is to jettison steel weights attached to the sub and shoot back to the surface. (See pictures of Cameron's sub.)
Meanwhile, the expedition's scientific support team awaits his return aboard the research ships Mermaid Sapphire and Barakuda, 7 miles (11 kilometers) up. (Video: how sound revealed that Challenger Deep is the deepest spot in the ocean.)
"We're now a band of brothers and sisters that have been through this for a while," marine biologist Doug Bartlett told National Geographic News from the ship before the dive.
"People have worked for months or years in a very intensive way to get to this point," said Bartlett, chief scientist for the DEEPSEA CHALLENGE program, a partnership with the National Geographic Society and Rolex. (The Society owns National Geographic News.)
"I think people are ready," added Bartlett, of the Scripps Institution of Oceanography in San Diego, California. "They want to get there, and they want to see this happen."
Rendezvous at Challenger Deep
Upon touchdown at Challenger Deep, Cameron's first target is a phone booth-like unmanned "lander" dropped into the trench hours before his dive.
Using sonar, "I'm going to attempt to rendezvous with that vehicle so I can observe animals that are attracted to the chemical signature of its bait," Cameron told National Geographic News before the dive.
He'll later follow a route designed to take him through as many environments as possible, surveying not only the sediment-covered seafloor but also cliffs of interest to expedition geologists.
"I'll be doing a bit of a longitudinal transect along the trench axis for a while, and then I'll turn 90 degrees and I'll go north and work myself up the wall," saidCameron, also a National Geographic Society explorer-in-residence. (Listen:James Cameron on becoming a National Geographic explorer.)
Though battery power and vast distances limit his contact with his science team to text messaging and sporadic voice communication, Cameron seemed confident in his mission Friday. "I'm pretty well briefed on what I'll see," he said.
Bullet to the Deep
To get to this point, Cameron and his crew have spent seven years reimagining what a submersible can be. The result is the 24-foot-tall (7-meter-tall)DEEPSEA CHALLENGER.
Engineered to sink upright and spinning, like a bullet fired straight into the Mariana Trench, the sub can descend about 500 feet (150 meters) a minute—"amazingly fast," in the words of Robert Stern, a marine geologist at the University of Texas at Dallas.
Pre-expedition estimates put the Challenger Deep descent at about 90 minutes. (Animation: Cameron's Mariana Trench dive compressed into one minute.)
By contrast, some current remotely operated vehicles, or ROVs, descend at about 40 meters (130 feet) a minute, added Stern, who isn't part of the expedition.
Andy Bowen, project manager and principal developer of the Nereus, an ROV that explored Challenger Deep in 2009, called the DEEPSEA CHALLENGER "an extremely elegant solution to the challenge of diving a human-occupied submersible to such extreme depths."
"It's been engineered to be very effective at getting from the surface to the seafloor in as quick a time as possible," said Bowen, of Woods Hole Oceanographic Institution, who also isn't part of the current expedition.
And that's just the idea, the DEEPSEA CHALLENGE team says: The faster Cameron gets there, the more time for science. (Read more about DEEPSEA CHALLENGE science.)
Pursuing speed and science in tandem makes the DEEPSEA CHALLENGERtest dives—and even the Mariana Trench mission—perhaps as unorthodox as the sub itself.
Typically "you conduct a sea trial for a vehicle, you pronounce it fit for service, andthen you develop a science program around it," Cameron said before heading to the trench. "We collapsed that together into one expedition, because [we were] fairly confident the vehicle would work—and it is."
Techno Torpedo
Now, at the bottom of the trench, the sub's custom-designed foam filling and the pressure-resistant shape of the "pilot sphere"—are helping protect Cameron from the equivalent of 8 tons pressing down on every square inch (1,125 kilograms per square centimeter). (Video: how sub sphere protects Cameron.)
Among the sub's tools are a sediment sampler, a robotic claw, a "slurp gun" for sucking up small sea creatures for study at the surface, and temperature, salinity, and pressure gauges.
While that might sound like a gearhead's paradise, Cameron knows he'll "have to be able to prioritize."
"Is my manipulator working properly? Do I still have room in my sample drawer? And do I still have the ability to take a [sediment] core sample? ... I only have [tools for] three sediment cores available on the vehicle, so I have to choose wisely when to use them."
By contrast, the sub's multiple 3-D cameras will be whirring almost continually, and not just for the benefit of future audiences of planned documentaries.
"There is scientific value in getting stereo images," Cameron said, "because ... you can determine the scale and distance of objects from stereo pairs that you can't from 2-D images."
But, Scripps's Bartlett said, "it's not just the video." The sub's lighting of deepwater scenes—mainly by an 8-foot (2.5-meter) tower of LEDs—is "so, so beautiful. It's unlike anything that you'll have seen from other subs or other remotely operated vehicles."
The Search for Life
Right now it's a mystery what Cameron is seeing, sampling, and filming at depth, in part because so little is known about the Challenger Deep environment.
The only glimpses scientists have had of the region, via two ROV missions, showed a seafloor covered in light gray, silky mud.
Cameron may be detecting subtle signs of life—burrows or tracks or fecal piles—said DEEPSEA CHALLENGE biological oceanographer Lisa Levin, also of Scripps, who's monitoring the expedition from afar.
If the water's clear, she added, Cameron may be seeing jellyfish or xenophyophores—giant, single-celled, honeycomb-shaped creatures already filmed in other areas of the Mariana Trench. (See "Giant 'Amoebas' Found in Deepest Place on Earth.")
"If we get lucky," Cameron said before the dive, "we should find something like a cold seep, where we might find tube worms." Cold seeps are regions of the ocean floor somewhat like hydrothermal vents (video) that ooze fluid chemicals at the same temperature as the surrounding water.
Earlier this month, during a test dive near Papua New Guinea, Cameron brought back enormous shrimplike creatures from five miles (eight kilometers) down. At 7 inches (17 centimeters) long, the animals are "the largest amphipods ever seen at that kind of depth," chief scientist Bartlett said. "And we saw one on camera that was perhaps twice that size."
At Challenger Deep depths, though, the calcium animals need to form shells dissolves quickly. It's unlikely—though not impossible—that Cameron is finding shelled creatures, but if he does, the discovery would be a scientific jaw-dropper.
Even if he uncovers "a rock with a shell limpet or some kind of bivalve in the mud"—such as a clam, perhaps—"that would be exciting," Scripps's Levin said.
Aliens of the Abyss
Expedition astrobiologist Kevin Hand, of NASA, imagines that the life-forms Cameron might be encountering could help fine-tune the search for extraterrestrial life.
For instance, scientists think Jupiter's moon Europa could harbor a global ocean beneath its thick shell of ice—an ocean that, like Challenger Deep, would be lightless, near freezing, and home to areas of intense pressure. (See "Could Jupiter Moon Harbor Fish-Size Life?")
By studying the wavelengths of light, or spectra, reflected off life-forms and sediments brought up by Cameron, Hand should get a better idea of which minerals are needed for life in such an environment. This, in turn, might help him design a space probe better able to detect signs of life on Europa.
"There's an old adage in geology that the best geologist is the one that's seen the most rocks," said Hand, a National Geographic emerging explorer.
"I think astrobiology could have a similar adage, in that our best capability for finding life elsewhere—and knowing it when we see it—will come from having a comprehensive understanding of all the various extremes of life on Earth."
And for UT Dallas's Stern, DEEPSEA CHALLENGER's rock-sampling capability offers the opportunity to better understand our planet's inner workings.
"Challenger Deep is the deepest cut into the solid Earth," Stern said, "and this gives us a chance to see deeper into the Earth than anywhere else."
Once the trench-dive data, specimens, and imagery have been analyzed, National Geographic magazine plans to reveal the full results in a special issue on next-generation exploration in January 2013.
"A Turning Point"
By returning humans to the so-called hadal zone—the ocean's deepest level, below 20,000 feet (6,000 meters)—the Challenger Deep expedition may represent a renaissance in deep-sea exploration.
While ROVs are much less expensive than manned subs, "the critical thing is to be able to take the human mind down into that environment," expedition member Patricia Fryer said, "to be able to turn your head and look around to see what the relationships are between organisms in a community and to see how they're behaving—to turn off all the lights and just sit there and watch and not frighten the animals, so that they behave normally.
"That is almost impossible to do with an ROV," said Fryer, a marine geologist at the Hawai'i Institute of Geophysics & Planetology.
In fact, Cameron is so confident in his star vehicle that he started mulling sequels even before the trench dive.
Phase two might include adding a thin fiber-optic tether to the ship, which "would allow science observers at the surface to see the images in real time," he said. "And phase three might be taking this vehicle and creating a second-generation vehicle."
DEEPSEA CHALLENGE, then, may be anything but a one-hit wonder. ToBartlett, the Mariana Trench expedition could "represent a turning point in how we approach ocean science.
"I absolutely think that what you're seeing is the start of a program, not just one grand expedition."
Dozens homeless in western Mexico after huge quake
(Reuters) - Dozens of families cleared rubble from their destroyed homes in southwestern Mexico on Wednesday following a major 7.4-magnitude earthquake that caused landslides, knocked down school walls and cracked a church tower.
At least 100 houses collapsed and 1,000 were damaged near the epicenter of Tuesday's quake in the municipality of Ometepec in Guerrero state, said Jorge Catalan, an official from the Ministry of Social Development.
No one was killed, but many residents, terrified by repeated aftershocks, spent the night outside and local officials said they were preparing shelters and food aid for people who lost their homes.
Eleven people were injured in the tremor, the strongest to hit the country since the devastating 8.1-magnitude quake of 1985 that killed thousands in Mexico City.
Large boulders from landslides blocked the road to the small town of Paso Cuaulote where nearly all 150 villagers, who grow beans and corn, were hit.
"I thought the world was going to end," said farmer Vicente Santiago, 30, surveying a crumbled wall in his father's cinder block home. His father, taking a nap when the quake hit, escaped unharmed even after the roof caved in.
Maria Lopez, 33, fled her home with her 2-week-old baby boy and spent the night by the river with the rest of the town.
"Rocks were falling from the mountainside onto the house," said Lopez clutching her baby outside her seriously cracked mud-brick home.
Students picked their way through rubble-strewn classrooms on Wednesday at one of the three primary schools damaged in the municipality.
"The children were shouting. We had to evacuate," said teacher Abel Hernandez.
In the nearby town of Igualapa, one of the towers on the colonial-era church crumbled, although locals were still holding a service inside.
In Mexico City, residents were largely spared, with only small cracks in buildings and minor damage to one subway line and a bridge. Mexico City is about 200 miles (320 km) north-northeast of the epicenter.
The capital's repair bill for the quake, which was felt as far away as Guatemala should come in under $2 million, Mayor Marcelo Ebrard said.
The type of the earthquake - it shook the city from side to side rather than up and down - and better construction regulations since 1985 saved the city from more serious damage, Ebrard told national television.
(Additional reporting by Elinor Comlay in Mexico City; Writing by Mica Rosenberg; Editing by Peter Cooney)
Benz's electric supercar a goer
Click for more photosMercedes-Benz SLS E-Cell
Mercedes-Benz have announced a limited run of the zero emission SLS (Gullwing) E-Cell electric vehicle as a green flagship from 2013.
Australia could be on the shortlist for the ‘Gullwing’ EV.
The world’s first fully electric supercar – the Mercedes-Benz Gullwing E-Cell – has been confirmed to go on sale by the end of this year and be in customer hands by early 2013.
Mercedes is yet to announce the price but it’s tipped to be close to $1 million because of the complex build process and the high cost of the battery pack and performance electric motor.
“It will be on the pricelist for an exclusive clientele this year and deliveries will start in 2013,” the head of AMG, Ola Kaellenius told Australian media in Geneva overnight.
Advertisement: Story continues below
“We don’t know [how many we will sell]. We’re breaking new ground, we’re working on the philosophy ‘build it and they will come’. We are entering the segment with an open mind.”
Australia is yet to be confirmed as a market for the vehicle even though more AMG cars are sold per-capita locally than in North America. Mercedes sold 44 Gullwings in Australia in 2010 and 30 last year even though they cost in excess of $400,000.
“We are already in discussions with the markets. We are deciding in the next few months if we build it in right-hand drive,” Kaellenius says. “We know Australia is an important market for AMG. It is technically possible to build the vehicle in right-hand-drive. But we have to decide if there is a business case behind it.”
Despite the high price of the emerging technology, Mercedes says it is already holding orders for the E-Cell and expects to sell “triple digit figures”.
So far, more than 6000 V8-powered Gullwing SLS coupes have been sold worldwide; the car maker estimates it could sell at least a few hundred of the pure electric model.
Mercedes has already tested the E-Cell on the Nurburgring but is yet to release a lap time. However, Drive has been told it is only marginally slower than the V8.
The E-Cell sprints from 0 to 100km/h in 4.0 seconds (compared to 3.8 seconds for the V8) and has 200km of driving range in ideal conditions between recharges.
The demonstration E-Cell has 392kW of power and 880Nm of torque (compared to 420kW and 650Nm for the V8) but the AMG boss indicated there may be more power to come for the production car.
The E-Cell’s battery pack adds about 500kg to the overall weight of the vehicle – pushing it beyond two tonnes – but because it is mounted in the “spine” of the vehicle, it has a lower centre of gravity than the V8 model, AMG claims.
The E-Cell is effectively a test bed for possible hybrid versions of future AMG models.
“Electrification will enter the performance segment at some point in time. We decided we’d use the E-Cell project to build up the technical knowledge inside the company and then you can combine it in any form you like,” Kaellenius says
Yahoo board battle may begin within the next week
A potentially nasty battle to reshape Yahoo's board of directors will begin within the next week unless the troubled Internet company submits to the demands of a major shareholder.
Third Point LLC, a hedge fund that owns a 5.8 percent stake in Yahoo, issued its ultimatum in a letter Wednesday to company CEO Scott Thompson.
The letter, released in a regulatory filing, comes a month after Third Point first announced that it wanted four seats on a Yahoo board already undergoing an overhaul.
The board currently consists of 11 directors, but Chairman Roy Bostock and three other members announced they will step down at Yahoo's annual meeting. The departures are part of an attempt to placate shareholders frustrated with a long-running financial funk that has depressed the company's stock price.
Third Point believes Yahoo would fare better if the hedge fund's representatives were in the boardroom. Third Point's proposed directors are: Daniel Loeb, the hedge fund's manager; former NBC Universal CEO Jeff Zucker; former MTV Networks executive Michael Wolf and turnaround specialist Harry Wilson.
In Wednesday's letter, Loeb told Thompson he was disappointed with Yahoo's "dismissive" attitude toward Third Point's candidates since the two men spoke in a Feb. 17 conversation.
"The board's stonewalling, apparent insouciance and decision not to engage with us in a serious manner, has left us no choice but to directly approach our fellow owners" in an attempt to get Third Point's slate elected as directors, Loeb wrote.
In a statement, Yahoo said its board's nominating committee is still considering "a wide range of highly qualified candidates" for its board. The company appointed two new directors, Alfred Amoroso and Maynard Webb, to its board last month.
"The committee has included Third Point's candidates in its thorough review process and will make its recommendations to the full board in due course," Yahoo said.
Unless Yahoo accepts Third Point's candidates on the board, Loeb pledged to begin his campaign within the next week. That could lead to a showdown that culminates at Yahoo's annual meeting, which is usually held in late June.
The mutiny would threaten to distract Thompson as he plots his turnaround strategy. Citing unnamed people, the technology blog All Things D recently reported Thompson is considering a tumultuous shake-up that could include thousands of job cuts.
Yahoo has only said it "is engaged in a process that will generate significant strategic change."
Given those plans Loeb urged Thompson to negotiate a truce. "You appear to have enough battles to fight already," Loeb wrote.
Yahoo shares rose 5 cents to $14.68 in Wednesday's extending trading
Third Point LLC, a hedge fund that owns a 5.8 percent stake in Yahoo, issued its ultimatum in a letter Wednesday to company CEO Scott Thompson.
The letter, released in a regulatory filing, comes a month after Third Point first announced that it wanted four seats on a Yahoo board already undergoing an overhaul.
The board currently consists of 11 directors, but Chairman Roy Bostock and three other members announced they will step down at Yahoo's annual meeting. The departures are part of an attempt to placate shareholders frustrated with a long-running financial funk that has depressed the company's stock price.
Third Point believes Yahoo would fare better if the hedge fund's representatives were in the boardroom. Third Point's proposed directors are: Daniel Loeb, the hedge fund's manager; former NBC Universal CEO Jeff Zucker; former MTV Networks executive Michael Wolf and turnaround specialist Harry Wilson.
In Wednesday's letter, Loeb told Thompson he was disappointed with Yahoo's "dismissive" attitude toward Third Point's candidates since the two men spoke in a Feb. 17 conversation.
"The board's stonewalling, apparent insouciance and decision not to engage with us in a serious manner, has left us no choice but to directly approach our fellow owners" in an attempt to get Third Point's slate elected as directors, Loeb wrote.
In a statement, Yahoo said its board's nominating committee is still considering "a wide range of highly qualified candidates" for its board. The company appointed two new directors, Alfred Amoroso and Maynard Webb, to its board last month.
"The committee has included Third Point's candidates in its thorough review process and will make its recommendations to the full board in due course," Yahoo said.
Unless Yahoo accepts Third Point's candidates on the board, Loeb pledged to begin his campaign within the next week. That could lead to a showdown that culminates at Yahoo's annual meeting, which is usually held in late June.
The mutiny would threaten to distract Thompson as he plots his turnaround strategy. Citing unnamed people, the technology blog All Things D recently reported Thompson is considering a tumultuous shake-up that could include thousands of job cuts.
Yahoo has only said it "is engaged in a process that will generate significant strategic change."
Given those plans Loeb urged Thompson to negotiate a truce. "You appear to have enough battles to fight already," Loeb wrote.
Yahoo shares rose 5 cents to $14.68 in Wednesday's extending trading
JNTU-HYD : B.Tech 4-1 (R07,R05,RR) Regular/Supple Exams Results(Dec 2011)
U can check ur results from the below URL's. U can use the alternative Links also
Note : while checking ur results...If you are unable to get the Security Code picture (captcha). Right Click on the Image Location and Click "Copy Image Location".... u can find the code at the end of the copied URL... its of 5 Digits
B.Tech. IV Year I Semester (R07) Results - November, 2011
B.Tech. IV Year I Semester (R05) Results - November, 2011
B.Tech. IV Year I Semester (RR) Results - November, 2011
Note : Last Date For RC/RV is 9th Feb 2012
R07 % & Credit Calculators
EEE, ECE, ETE, CSE, IT, ICE, EIE, ECM, BME & CHEMICAL ENGINEERING
CIVIL
BIO-TECH
MECH
AERONAUTICAL ENGINEERING
R07 (Lateral Entry Scheme) Percentage / credit Calculator
Note: As per JNTU R07 regulation, percentage is calculated for BEST 216 credits out of 224 credits.so we had prepared the calculator in such a way to calculate the % for Best of 216 credits only.
Subscribe to:
Posts (Atom)