Monday, June 18, 2012

Rodney King, whose beating led to LA riots, dies

FILE - This April 13, 2012 file photo shows Rodney King posing for a portrait in Los Angeles. King, the black motorist whose 1991 videotaped beating by Los Angeles police officers was the touchstone for one of the most destructive race riots in the nation's history, has died, his publicist said Sunday, June 17, 2012. He was 47. (AP Photo/Matt Sayles, file)

FILE - This April 13, 2012 file photo shows Rodney King posing for a portrait in Los Angeles. King, the black motorist whose 1991 videotaped beating by Los Angeles police officers was the touchstone for one of the most destructive race riots in the nation's history, has died, his publicist said Sunday, June 17, 2012. He was 47. (AP Photo/Matt Sayles, file)

FILE - This March 31, 1991 image made from video shot by George Holliday shows police officers beating a man, later identified as Rodney King. King, the black motorist whose 1991 videotaped beating by Los Angeles police officers was the touchstone for one of the most destructive race riots in the nation's history, has died, his publicist said Sunday, June 17, 2012. He was 47. (AP Photo/Courtesy of KTLA Los Angeles, George Holliday)

FILE - This file photo of Rodney King was taken three days after his videotaped beating in Los Angeles on March 6, 1991. King, the black motorist whose 1991 videotaped beating by Los Angeles police officers was the touchstone for one of the most destructive race riots in the nation's history, has died, his publicist said Sunday, June 17, 2012. He was 47. (AP Photo/Pool, File)

FILE - This July 20, 1993 file photo shows Rodney King speaking during an appearance on KFI-AM radio's "Bill Handel and Mark Whitlock" show in Los Angeles. King, the black motorist whose 1991 videotaped beating by Los Angeles police officers was the touchstone for one of the most destructive race riots in the nation's history, has died, his publicist said Sunday, June 17, 2012. He was 47. (AP Photo/Nick Ut, file)

FILE - This July 16, 1992 file photo shows Rodney King being escorted from jail in Santa Ana, Calif. after he was arrested for investigation of drunken driving. King, whose videotaped beating by police in 1991 led to LA race riots, has died at 47. (AP Photo/Kevork Djansezian, file)

(AP) ? His beating stunned the nation, left Los Angeles smoldering and helped reshape race relations and police tactics. And in a quavering voice on national television, Rodney King pleaded for peace while the city burned.

But peace never quite came for King ? not after the fires died down, after two of the officers who broke his skull multiple times were punished, after Los Angeles and its flawed police department moved forward. His life, which ended Sunday at age 47 after he was pulled from the bottom of his swimming pool, was a continual struggle even as the city he helped change moved on.

The images ? preserved on an infamous grainy video ? of the black driver curled up on the ground while four white officers clubbed him over 50 times with batons ? became a national symbol of police brutality in 1991. More than a year later, when the officers' acquittals touched off one of the most destructive race riots in history, his scarred face and softspoken question ? "Can we all get along?" ? spurred the nation to confront its difficult racial history.

But while Los Angeles race relations and the city's police department made strides forward, King kept coming before police and courts, struggling with alcohol addiction and arrests, periodically re-appearing publicly for a stint on "Celebrity Rehab" or a celebrity boxing match. He spent the last months of his life promoting a memoir he titled "The Riot Within: From Rebellion to Redemption."

King was declared dead at a hospital after his fianc?e called 911 at 5:25 a.m. to say she found him submerged in the pool at his home in Rialto, about an hour's drive from Los Angeles. Officers found King in the deep end of the pool, pulled him out and tried unsuccessfully to revive him with CPR.

An autopsy was expected to determine the cause of death within two days; police found no alcohol or drug paraphernalia near the pool and said foul play wasn't suspected. King's next-door neighbor said that around 3 a.m., she heard music and someone "really crying, like really deep emotions. ... Like tired or sad, you know?"

"I then heard someone say, 'OK, Please stop. Go inside the house.' ... We heard quiet for a few minutes Then after that we heard a splash in the back."

King's death was a grim ending to a saga that began 21 years earlier when he fled from police after he was stopped for speeding. The 25-year-old, on parole from a robbery conviction had been drinking, which he later said led him to try to evade police. He was finally stopped by four Los Angeles police officers who struck him more than 50 times with their batons, kicked him and shot him with stun guns. He was left with 11 skull fractures, a broken eye socket and facial nerve damage.

A man who had quietly stepped outside his home to observe the commotion videotaped most of it and turned a copy over to a TV station. It was played over and over for the following year, inflaming racial tensions across the country.

It seemed that the videotape would be the key evidence to a guilty verdict against the officers, whose felony assault trial was moved to the predominantly white suburb of Simi Valley, Calif. Instead, on April 29, 1992, a jury with no black members acquitted three of the officers on state charges in the beating; a mistrial was declared for a fourth.

Violence erupted immediately, starting in Los Angeles. They lasted for three days, killing 55 people, injuring more than 2,000 and setting swaths of Los Angeles aflame, causing $1 billion in damage. Police, seemingly caught off-guard, were quickly outnumbered by rioters and retreated. As the uprising spread to the city's Koreatown area, shop owners armed themselves and engaged in running gun battles with looters.

King ? who said in his memoir that FBI agents had urged him to keep a low profile if the officers were acquitted, expecting violence ? appeared at a news conference on the third day, asking for an end to the uprising. "Can we all get along?" he asked ? a question the city and nation have struggled to answer ever since.

Although the four officers who beat King ? Stacey Koon, Theodore Briseno, Timothy Wind and Laurence Powell ? were acquitted of state charges, Koon and Powell were convicted of federal civil rights charges and were sentenced to more than two years in prison. King received a $3.8 million civil judgment; one of the jurors in the case, Cynthia Kelley, is his fianc?e.

But he quickly lost the money as he invested in a record label and other failed ventures. He was arrested multiple times for drunken driving ? including last summer in Riverside, Calif.

Despite his troubles, King remained upbeat as he confronted the 20 year anniversary of the LA riots and considered his legacy.

"America's been good to me after I paid the price and stayed alive through it all," he told The Associated Press in an interview earlier this year. "This part of my life is the easy part now."

He had three daughters and was engaged to Kelley.

He returned to the spotlight earlier this year as historians and news outlets explored the impact of the riots on its 20th anniversary, including the reforms made by the Los Angeles Police Department.

"Through all that he had gone through with his beating and his personal demons he was never one to not call for reconciliation and for people to overcome and forgive," Rev. Al Sharpton said Sunday. "History will record that it was Rodney King's beating and his actions that made America deal with the excessive misconduct of law enforcement."

Attorney Harland Braun, who represented one of the police officers, Briseno, in his federal trial, said King's case never would have gained the prominence it did without the videotape of his beating.

"If there hadn't been a video there would have never been a case," Braun said. "In those days, you might have claimed excessive force but there would have been no way to prove it."

The video also sparked an examination of Los Angeles police tactics under then-Police Chief Daryl Gates.

"The Rodney King beating stands as a landmark in the recent history of law enforcement, comparable to the Scottsboro case in 1931 and the Serpico case in 1967," said a July 1991 report produced by an independent commission led by Warren Christopher, who later became Secretary of State.

The report determined that despite many good officers, there were "a significant number of officers in the LAPD who repetitively use excessive force against the public."

Despite that scrutiny, the department continued to face scandals and critics of its practices until the U.S. government intervened. The department operated under a decade-long consent decree with the U.S. Justice Department' civil rights division to implement reforms on how it uses force and handles complaints; the department also gained more civilian oversight. The decree wasn't formally lifted until 2009.

The Rev. Jesse Jackson, who knew King for years, said he was more of a victim than a hero, and that his death reminded the nation of how far it still needs to go.

Gardea described King as a quiet neighbor until Sunday morning. Cory Hudson, King's cousin who lives nearby, said King enjoyed swimming and was known to get into the pool at night.

"It's just sad. I feel bad for all the family members," Hudson said. "It's been rough. And he was just getting his life really together."

Braun, the attorney saw King as "a sad figure swept up into something bigger than he was.

"He wasn't a hero or a villain."

___

Associated Press writers Raquel Maria Dillon in Rialto and Linda Deutsch, Chris Weber and John Antczak in Los Angeles contributed to this report.

Associated Press

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Syria accused of violence rise after U.N. monitor halt

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Sunday, June 17, 2012

Small Engine Repair: A Way to Lessen Fuel Expenditures | Home ...

Small Engine Repair: A Way to Lessen Fuel Expenditures

post by Grayserr G.

?

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The continuing increase of fuel cost in the World Market is one of the major problems faced by most of the countries today. Fuel is one of the basic necessities as it helps the transportation of goods from one place to another. A reported change in the price of fuel can affect the costs of the food products being shipped. Not only transportation vehicles rely on fuel, also mowers can be used with it.

People following strict budget never stop thinking of various ways to lessen fuel expenses. One means of saving is through small engine repair. With this, the mowers will be reconstructed in order to be fuel efficient since old models tend to absorb more fuel than the regular automobile engines. Nowadays, people are flocking to the market just to get hold of their own fuel-efficient mowers so that they can save-up from the expensive fuel costs.

Small engine runs the fuel-efficient mowers since the type of engine used is easy to assemble and preserve its condition. In addition, small engine tend to use less fuel than larger engine for the reason that the small engine is two-stroke while the latter type of engine is four-stroke. A two-stroke engine only needs half the rotations in order for the fuel to ignite and produce the required energy to control the mower or other equipment like golf cart. People chooses small engine repair because it helps with fuel maintenance and makes the mower or any equipment installed with small engine be controlled or maneuver trouble-free. Another advantage acquired is that the lesser heat is generated from the motor hence the lifespan of the equipment will last in comparison with others using the old model of engine. Also the temperature of the small engine can be cooled down just with the aid of the breeze or wind.

In recognition with the advances made by the companies and manufacturers of engines, people can choose from the wider variety of options on how to live in a more efficient and satisfying life. Consumers can even choose what kind of fuel to power his or her mower that had undergone a small engine repair. One can use gasoline, regular diesel which is cheaper than the gasoline, biodiesel which is produced from vegetable oil and fat, propane which is an alternative fuel that can power the latest models of mowers, or other assortment of fuels being formulated by oil companies.

This entry was posted in Small Engine Repair and tagged landscaping, lawn mower, new jersey, small engine repair, small engines, south jersey, tractor repair, tractors by home9958. Bookmark the permalink.

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Saturday, June 16, 2012

Catching some rays: Organic solar cells make a leap forward

ScienceDaily (June 14, 2012) ? Drawn together by the force of nature, but pulled apart by the force of man -- it sounds like the setting for a love story, but it is also a basic description of how scientists have begun to make more efficient organic solar cells.

At the atomic level, organic solar cells function like the feuding families in Romeo and Juliet. There's a strong natural attraction between the positive and negative charges that a photon generates after it strikes the cell, but in order to capture the energy, these charges need to be kept separate.

When these charges are still bound together, they are known to scientists as an exciton. "The real question that this work tries to answer is how to design a material that will make splitting the exciton require less energy," said senior chemist Lin Chen of the U.S. Department of Energy's (DOE) Argonne National Laboratory.

Excitons can be thought of as a sort of "quasiparticle," Chen said, because they exhibit certain unique behaviors. When the two charged regions of the exciton -- the electron and a region known as a "hole" -- are close together, they are difficult to pry apart.

"The closer the hole and the electron regions are inside an exciton, the more likely they are to recombine without generating electricity," Chen said.

When energy is added to the system, however, the charges begin to separate, rendering the electrons and holes completely free and eventually allowing for the possibility of generating current and extracting electricity

"The closer the hole and the electron regions are inside an exciton, the more likely they are to recombine without generating electricity," Chen said. "But if they are already 'pre-separated,' or polarized, the more likely they are to escape from this potential trap and become effective charge carriers."

In the new experiment, Chen and her colleagues examined how four different molecules in the polymer layer in the middle of a solar cell generated different exciton dynamics. They discovered that more heavily polarized excitons yielded more efficient polymer-based solar cells.

"If the conventional exciton, right after it is generated, contains the hole and electron in almost the same location, these new materials are generating an exciton that is much more polarized at the beginning," Chen said. Currently, the collaborative team is exploring new materials for high-efficiency organic solar cells based on these findings.

Organic solar cells still have a ways to go to get close to the efficiency of their inorganic, silicon-based competitors, but they remain much more attractive from a cost perspective. Further research into the electronic dynamics of organic photovoltaics is essential to improving their efficiency and thus making solar power cost-competitive with conventional energy sources, Chen said.

The work has been recently published in the Journal of the American Chemical Society.

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The above story is reprinted from materials provided by DOE/Argonne National Laboratory. The original article was written by Jared Sagoff.

Note: Materials may be edited for content and length. For further information, please contact the source cited above.


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Friday, June 15, 2012

Gone fishing: Researchers' imaging technique trolls in quiet cellular seas

Gone fishing: Researchers' imaging technique trolls in quiet cellular seas [ Back to EurekAlert! ] Public release date: 14-Jun-2012
[ | E-mail | Share Share ]

Contact: Liz Ahlberg
eahlberg@illinois.edu
217-244-1073
University of Illinois at Urbana-Champaign

CHAMPAIGN, Ill. Experienced anglers know that choppy waters make for difficult fishing, so they try not to rock the boat. Thanks to a new microscopy technique, cell biology researchers can heed that same advice.

University of Illinois researchers developed a method they call "trolling AFM," which allows them to study soft biological samples in liquid with high resolution and high quality. Led by mechanical science and engineering professor Min-Feng Yu, the group published its findings in the journal Nanotechnology.

"We developed a highly sensitive method for high-resolution imaging of soft biological samples, such as living cells, in their physiological condition," said Majid Minary, a recent graduate of Yu's group and first author of the paper. Minary now is a professor at the University of Texas-Dallas. "We improved the quality factor of common atomic force microscopy imaging methods by two orders of magnitude," Minary said.

The widely used atomic force microscope provides images of tiny structures with high resolution at the atomic scale. The AFM has a sharp probe at the end of an arm, called a cantilever. The tip of the probe skims the surface of a sample to measure mechanical, electrical or chemical properties.

When scientists want to study cells, tissue or other live biological materials, the samples must be submerged in a liquid to keep them alive. This poses difficulties for atomic force microscopy, because the cantilever has to be submerged as well.

Cells and tissues are so soft that if the AFM probe were simply dragged across the surface, it would damage or displace the sample instead of reading it. Therefore, scientists have to operate the AFM in oscillation mode with the probe gently tapping along the sample and detecting resistance.

But oscillation in liquid brings a tide of complications in its wake.

Oscillating a relatively large structure, such as an AFM cantilever, through liquid also causes the liquid to surge up and down with the oscillation, like waves in a tidal pool, causing even more drag.

"There's a huge amount of hydrodynamic drag associated with operating a such a big cantilever, compared to the resolution you're trying to approach," said Yu, "so it causes lots of disturbance, recorded as noise, which overwhelms all the actual data you're trying to get from the sample."

The high noise level requires the probe to tap harder to find a signal. This means the tip deforms a cell as the probe presses down, and only large, stiff structural elements such as the nucleus are visible, rendering AFM unable to resolve the membrane's structure, properties and contours with high resolution.

Yu's group devised a solution to the problem by allowing the cantilever to oscillate in air above the liquid while the sample is still submerged. They attached a thin, long nanoneedle a structure the group developed previously to the end of the probe, effectively extending the tip.

"We call it 'trolling mode' AFM, as in fishing where a part of the fishing line is immersed in water and the other part above," Yu said.

While AFM of soft tissues with a submerged probe is like trying to club fish with a large paddle in a wave pool, the new arrangement is like trolling a fishing line in a calm pond. The nanoneedle displaces very little of the liquid and causes very little drag, yet is very responsive, so that the cantilever can oscillate very gently with very small amplitude.

"Once you remove the noise, all the information you're getting is from the sample, instead of from the interaction between the tip and the liquid," Yu said.

Using trolling AFM, the group gained high-resolution topographical images of human cells.

"We can tap with such small force that we can reveal the regional contours of the membrane," said Ning Wang, a professor of mechanical science and engineering and a co-author of the paper. "Not only that, more importantly, we get the viscoelastic map. We put a little bit of force on it, and see how viscoelastic it is."

Thanks to the minimal disturbance, trolling AFM also can operate at high frequency, which could allow researchers to study the dynamics of cellular structures that previously were not detectable.

Next, the researchers want to expand the utility of this instrument with additional dynamic measurement capability. The team also will work with biologists to identify issues relating to cell membrane and refine trolling AFM to resolve structures in the membrane.

###

The National Science Foundation and the National Institutes of Health supported this work. Yu and Wang are also affiliated with the Beckman Institute for Advanced Science and Technology at the U. of I.

Editor's notes: To contact Min-Feng Yu, call 217-333-9246; email mfyu@illinois.edu. To contact Ning Wang, call 217-265-0913; nwangrw@illinois.edu.

The paper, "Intrinsically High-Q Dynamic AFM Imaging in Liquid With a Significantly Extended Needle Tip," is available online at http://iopscience.iop.org/0957-4484/23/23/235704/.


[ Back to EurekAlert! ] [ | E-mail | Share Share ]

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Gone fishing: Researchers' imaging technique trolls in quiet cellular seas [ Back to EurekAlert! ] Public release date: 14-Jun-2012
[ | E-mail | Share Share ]

Contact: Liz Ahlberg
eahlberg@illinois.edu
217-244-1073
University of Illinois at Urbana-Champaign

CHAMPAIGN, Ill. Experienced anglers know that choppy waters make for difficult fishing, so they try not to rock the boat. Thanks to a new microscopy technique, cell biology researchers can heed that same advice.

University of Illinois researchers developed a method they call "trolling AFM," which allows them to study soft biological samples in liquid with high resolution and high quality. Led by mechanical science and engineering professor Min-Feng Yu, the group published its findings in the journal Nanotechnology.

"We developed a highly sensitive method for high-resolution imaging of soft biological samples, such as living cells, in their physiological condition," said Majid Minary, a recent graduate of Yu's group and first author of the paper. Minary now is a professor at the University of Texas-Dallas. "We improved the quality factor of common atomic force microscopy imaging methods by two orders of magnitude," Minary said.

The widely used atomic force microscope provides images of tiny structures with high resolution at the atomic scale. The AFM has a sharp probe at the end of an arm, called a cantilever. The tip of the probe skims the surface of a sample to measure mechanical, electrical or chemical properties.

When scientists want to study cells, tissue or other live biological materials, the samples must be submerged in a liquid to keep them alive. This poses difficulties for atomic force microscopy, because the cantilever has to be submerged as well.

Cells and tissues are so soft that if the AFM probe were simply dragged across the surface, it would damage or displace the sample instead of reading it. Therefore, scientists have to operate the AFM in oscillation mode with the probe gently tapping along the sample and detecting resistance.

But oscillation in liquid brings a tide of complications in its wake.

Oscillating a relatively large structure, such as an AFM cantilever, through liquid also causes the liquid to surge up and down with the oscillation, like waves in a tidal pool, causing even more drag.

"There's a huge amount of hydrodynamic drag associated with operating a such a big cantilever, compared to the resolution you're trying to approach," said Yu, "so it causes lots of disturbance, recorded as noise, which overwhelms all the actual data you're trying to get from the sample."

The high noise level requires the probe to tap harder to find a signal. This means the tip deforms a cell as the probe presses down, and only large, stiff structural elements such as the nucleus are visible, rendering AFM unable to resolve the membrane's structure, properties and contours with high resolution.

Yu's group devised a solution to the problem by allowing the cantilever to oscillate in air above the liquid while the sample is still submerged. They attached a thin, long nanoneedle a structure the group developed previously to the end of the probe, effectively extending the tip.

"We call it 'trolling mode' AFM, as in fishing where a part of the fishing line is immersed in water and the other part above," Yu said.

While AFM of soft tissues with a submerged probe is like trying to club fish with a large paddle in a wave pool, the new arrangement is like trolling a fishing line in a calm pond. The nanoneedle displaces very little of the liquid and causes very little drag, yet is very responsive, so that the cantilever can oscillate very gently with very small amplitude.

"Once you remove the noise, all the information you're getting is from the sample, instead of from the interaction between the tip and the liquid," Yu said.

Using trolling AFM, the group gained high-resolution topographical images of human cells.

"We can tap with such small force that we can reveal the regional contours of the membrane," said Ning Wang, a professor of mechanical science and engineering and a co-author of the paper. "Not only that, more importantly, we get the viscoelastic map. We put a little bit of force on it, and see how viscoelastic it is."

Thanks to the minimal disturbance, trolling AFM also can operate at high frequency, which could allow researchers to study the dynamics of cellular structures that previously were not detectable.

Next, the researchers want to expand the utility of this instrument with additional dynamic measurement capability. The team also will work with biologists to identify issues relating to cell membrane and refine trolling AFM to resolve structures in the membrane.

###

The National Science Foundation and the National Institutes of Health supported this work. Yu and Wang are also affiliated with the Beckman Institute for Advanced Science and Technology at the U. of I.

Editor's notes: To contact Min-Feng Yu, call 217-333-9246; email mfyu@illinois.edu. To contact Ning Wang, call 217-265-0913; nwangrw@illinois.edu.

The paper, "Intrinsically High-Q Dynamic AFM Imaging in Liquid With a Significantly Extended Needle Tip," is available online at http://iopscience.iop.org/0957-4484/23/23/235704/.


[ Back to EurekAlert! ] [ | E-mail | Share Share ]

?


AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert! system.


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Thursday, June 14, 2012

Jeb Bush clarifies criticism of Republican Party

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